Instrument lock assembly for trocar

ES 2 287 656 T3

DESCRIPTION

Trocar instrument locking assembly. Cross reference to related request

This application is based on US Provisional Patent Application No. 60 / 506,737, filed September 30, 2003, entitled "Instrument lock assembly for trocar". Background of the invention

1. Field of the invention

The invention relates to trocar assemblies. More particularly, the invention relates to structures for locking an instrument in position relative to a trocar sleeve and / or trocar obturator.

2. Description of the prior art

A trocar assembly is a surgical instrument used to gain access to a body cavity. A trocar assembly generally comprises two main components, a trocar sleeve, comprised of a trocar housing and a trocar cannula, and a trocar obturator. The trocar cannula with the trocar obturator inserted through it is directed through the skin to access a body cavity through the tube in which endoscopic procedures and laparoscopic or arthroscopic surgery are to be performed. In order to penetrate the skin, the distal end of the trocar cannula is placed against the skin previously cut with a scalpel. The trocar obturator has a rounded tip or cutting edge at its distal end. By applying pressure against the proximal end of the trocar obturator, the tip is forced through the skin until it is inserted into the body cavity. The trocar cannula is inserted through the perforation made by the obturator and the obturator is removed, leaving the trocar cannula as an access route to the body cavity.

When inserting the trocar assembly into the patient, it is often desirable to use an endoscope or other instrument in conjunction with the trocar assembly. However, it is often difficult to hold the endoscope or other instrument in a desired position relative to the trocar assembly.

As such, there is a need for a convenient locking mechanism that facilitates the placement of endoscopes and other instruments with respect to a trocar assembly. The present invention provides such a locking mechanism.

US-5,725,504 describes a locking assembly for use with a trocar sleeve. It comprises a cam lever, but no elastomeric blocks.

US-A-6,080,134 describes a parenchymal bolt for locking surgical instruments comprising cam levers and an elastomeric block.

Summary of the invention

It is, therefore, an object of the present invention to provide a locking assembly for use in conjunction with a trocar sleeve. The lock assembly includes a lock assembly housing having an opening extending therethrough. The locking assembly also includes a cam lever and an elastomeric block positioned within the housing of the locking assembly. The cam lever includes a first end pivotally fixed to the housing of the locking assembly and a second free end that is adapted for user actuation, in which rotation of the cam lever causes the elastomeric block to engage with an instrument that passes through the housing of the locking assembly to lock an instrument therewith.

An obturator is also provided for use with a trocar sleeve. The obturator includes a shaft having a distal end and a proximal end, and having a passageway extending therethrough. The obturator of the present invention also includes an instrument locking element at the proximal end of said shaft. The instrument locking member comprises a compressible material to abut against an instrument when the instrument is inserted and locks within the passageway.

It is another object of the present invention to provide an instrument locking element for use with a trocar. The instrument locking member includes a housing having a passageway extending therethrough, and a compressible material positioned within the housing to selectively abut against an instrument when an instrument is inserted and locked within said passageway. on the way.

Other objects and advantages of the present invention will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, which set forth certain embodiments of the invention.

Brief description of the drawings

Figure 1 is a perspective view of a trocar assembly in accordance with the present invention.

Figure 2 is an exploded view of the trocar assembly shown in Figure 1.

Figure 3 is a cross-sectional view of the trocar assembly shown in Figure 1.

Figure 4 is an exploded cross-sectional view of the trocar assembly shown in Figure 1.

Figure 5 is a detailed view of the rotary latch mechanism used in accordance with the present trocar assembly.

Figure 6 is an exploded view of the proximal seal assembly in accordance with the present trocar assembly.

Figure 7 is a perspective view from below of a segment of the gasket.

Figure 8 is a top view of a segment of the gasket.

Figure 9 is a cross-sectional view along the line IX-IX of Figure 8.

Figure 10 is a seal body composed of four seal segments as shown in Figures 7, 8 and 9.

Figure 11 is a top perspective view of a guard segment.

Figure 12 is a view from below of a guard segment.

Figure 13 is a shield composed of four shield segments as shown in Figures 11 and 12.

Figure 14 is a top perspective view of a flat mouth gasket assembly in accordance with the present invention.

Figure 15 is a cross-sectional view along the line XV-XV of Figure 14.

ES 2 287 656 T3

Figure 16 is a partial cross-sectional view along line XV-XV of Figure 14.

Figure 17 is an exploded view of the trocar sleeve according to the present invention.

Figure 18 is a further exploded view of the trocar sleeve according to the present invention.

Figure 19 is an assembled perspective view of the trocar sleeve shown in Figures 17 and 18.

Figure 20 is a rear perspective view of the trocar sleeve shown in Figures 17 and 18.

Figure 21 is an exploded view according to an alternative embodiment of the trocar sleeve.

Figure 22 is a partial exploded view according to an alternative embodiment of the trocar sleeve as shown in Figure 19.

Figures 23 and 24 are exploded views of a further embodiment of the trocar sleeve.

Figure 25 is a detailed view of the endoscopic locking mechanism.

Description of the preferred embodiments

Detailed embodiments of the present invention are described herein. It should be understood, however, that the described embodiments are merely exemplary of the invention, which can be realized in various ways. Therefore, the details described herein are not to be construed as limiting, but merely as the basis for the claims and as a basis for teaching one skilled in the art how to make and / or use the invention.

An endoscope locking assembly for a trocar assembly is described. The locking assembly provides for controlled placement of an endoscope with respect to a trocar assembly. Although the locking assembly is described as being adapted to lock an endoscope in position, the locking assembly can be used to lock other instruments without departing from the spirit of the present invention.

Referring to Figures 1 through 5, trocar assembly 10 generally includes a trocar cannula 12, a trocar obturator 14, and a trocar housing 16 (or puller). Trocar cannula 12 defines an interior lumen 18 having an open distal end portion 20 and an open proximal end portion 22. Proximal end portion 22 extends into, and is mounted to, distal end portion 24 of trocar housing 16. Trocar housing 16 has an open proximal end portion 26 defining an opening. The opening 28 is provided with a proximal gasket assembly 30 described in detail hereinafter. The opening 28 is further provided with a flat mouth seal assembly 32 positioned below the proximal seal assembly 28. Although the present gasket assembly is described as a proximal gasket assembly that is part of a double gasket system, the present gasket assembly can be used in a single gasket system.

In general, trocar sleeve 44 is comprised of a trocar cannula 12 and a trocar housing 16. Trocar housing 16 includes a first housing element 36 and a second housing element 38. The second housing element 38 is ultimately composed of a cover 38a of the second housing element and a base 38b of the second housing element. Although housing 16 is described as two components, it is contemplated that a single component could be used. The two-component housing shown aids in sample withdrawal.

Trocar obturator 14 can be slid into and removed from within trocar cannula 12 and inserted into trocar housing 16 and trocar cannula 12 through proximal seal assembly 30, mouth seal assembly 32 flat and the opening 28 of the trocar housing 16. An obturator puller 34 is provided at the proximal end of the trocar obturator 14 and a tip or blade (not shown) is formed at the distal end thereof. As is well known in the art, proximal seal assembly 30 cooperates with the exterior of instruments (eg, trocar obturators and other tools adapted for use in conjunction with trocar-based procedures) that extend through of the trocar sleeve 44 to sealingly engage the outer surface thereof and thereby prevent the passage of fluids through the trocar housing 16.

Rotational closure system

With respect to trocar housing 16 and with reference to Figures 1-5, trocar housing 16 is constructed of a first housing element 36 and a second housing element 38 that are selectively coupled for reasons that will be discussed below in more detail. The first and second housing elements 36, 38 include apertures 40, 42 aligned, shaped, and sized for receiving instruments that are selectively passed through the trocar housing 16.

As those skilled in the art will surely appreciate, it is important that the first and second housing members 36, 38 be securely attached during insertion of the trocar sleeve 44 into the abdominal wall, as well as during the normal course of a procedure. . However, it is also desirable to remove the first housing member 36 during removal of a sample, for example, from the abdominal cavity. Removal of the first housing member 36 allows the sample to pass through only the flat-mouth seal assembly 32, instead of passing through both the flat-mouth seal assembly 32 and the proximal seal assembly 30 . This provides easier sample removal and less damage to the sample during the withdrawal procedure.

The first housing member 36 supports the proximal seal assembly 30 and is seated on the second housing member 38 in which the flat-mouth seal assembly 32 is mounted. The first housing member 36 includes an opening 40 extending therethrough. The proximal seal assembly 30 is positioned within the opening 40 of the first housing member 36.

As for the second housing element 38, the second housing element 38 includes an opening 42 extending therethrough. The flat mouth seal assembly 32 is positioned within the opening 42 of the second housing element 38 adjacent the top surface 50 of the second housing element 38. In fact, and for reasons that will be discussed below in

In further detail, the peripheral flange 52 of the flat mouth seal assembly 32 is positioned directly adjacent the upper surface 50 of the second housing element 38 to engage with the lower surface 54 of the first housing element 36.

Connection of the first housing element 36 to the second housing element 38 is facilitated by a rotary latch mechanism 56. In particular, the first housing member 36 includes first and second arms 58 that extend downwardly. Each of the downwardly extending arms 58 includes a downwardly directed cam surface 60 and an outwardly directed closure surface 62.

Similarly, the second housing member 38 includes a closure ring 64 with a first and second closure 66 to respectively engage respective closure surfaces 62 of the first and second arms 58 extending downwardly of the first member 36 of accommodation. The closure ring 64 is axially aligned with the central axis of the trocar sleeve 44 and is located in an annular groove 68 around the perimeter of the flat mouth seal assembly 32. Although the locking ring 64 according to a preferred embodiment rotates about a central axis of the trocar housing 16, the locking ring 64 can rotate about other axes. The locking ring 64 can rotate about the central axis of the trocar sleeve 44, but is attached to the trocar housing 16 by a spring 70. The spring 70 holds the locking ring 64 in a locked position with a small amount of momentum. preload. However, the spring 70 allows rotation of the locking ring 64 during the attachment of the first housing member 36. The first and second closure 66 respectively include upwardly directed cam surfaces 72 that interconnect with downwardly directed cam surfaces 60 of the first and second arms 58 that extend downwardly of the first housing member 36.

The first and second closure 66 each include an upwardly directed cam surface 72, shaped and dimensioned to respectively engage the cam surfaces 60 of the downwardly extending arms 58. Similarly, the first and second closure 66 include inwardly directed closure surfaces 74 shaped and dimensioned to engage the outwardly directed closure surfaces 62 of the first and second arms 58 extending downwardly.

In practice, closure of the first and second housing elements 36, 38 is accomplished by passing the first and second arms 58 extending downwardly through holes 76 formed in the upper surface 50 of the second housing element 38. When the first and second downwardly extending arms 58 extend through respective holes 76 adjacent to the first and second closure 66 of the closure ring 64, the cam surfaces 60 of the respective first and second arms 58 that extend downwardly they engage the cam surfaces 72 of the first and second latches 66. The latch causes the closure ring 64 to rotate in a manner that allows the first and second downwardly extending arms 58 to extend beyond the first and second closure 66. This rotation is contrary to the momentum provided by the spring 70.

Once the first and second downwardly extending arms 58 travel past the first and second latches 66, spring 70 biasing seal ring 64 causes seal ring 64 to return to its original position and outwardly directed seal surfaces 62 of first housing member 36 to engage inwardly directed seal surfaces 74 second housing element 38 for fixedly coupling the first housing element 36 with the second housing element 38. The first and second housing elements 36, 38 are selectively disengaged through actuation of a lever 78 attached to the locking ring 64. Rotation of lever 78 causes lock ring 64 to rotate, moving first and second lock 66 disengaging from downwardly extending arms 58.

The upper surface 50 of the second housing element 38 includes holes 76 which allow the downwardly extending arms 58 of the first housing element 36 to pass therethrough with only a small amount of clearance. This limited play allows very little movement of the downwardly extending arms 58 either in the plane of the holes 76 or in bending. Thus, when the first housing element 36 is hooked to the second housing element 38, the only means for forcibly dismounting the first and second housing elements 36, 38 is to cut the first and second arms 58 extending downward or by pure tension on the supports themselves. The first and second arms 58 cannot bend out of the way or slip due to the size of the holes 76. This produces a very tight joint. Trocar housing 16 is removed by pushing lever 78 horizontally, causing locking ring 64 to rotate about the central axis of trocar sleeve 44 in a manner that overcomes spring force. The surgeon can access the lever 78 through a slot in the side of the trocar housing 16. When lever 78 is depressed, the first and second latches 66 of the latch ring 64 rotate past the first and second downwardly extending arms 58, and the first housing element 36 is released from the second housing element 38.

The first housing element 36 is attached to the second housing element 38 by a rotary latch mechanism 56 and a seal is needed between the first and second housing elements 36, 38 to maintain insufflation. This seal is achieved by using a flange 80 that extends downwardly on the lower surface 54 of the first housing member 36 to compress a portion of the flat mouth seal assembly 32 adjacent the upper surface 50 of the second housing member 38. Boss 80 and flat mouth gasket assembly 32 include opposing angular surfaces. This provides an angular contact surface between the protrusion 80 on the first housing element 36 and the contact surface of the flat mouth seal assembly 32 of the second housing element 38. This provides an easier attachment of the first housing member 36 and allows vertical displacement beyond the distance required to seal with no effect on the operational capabilities of the flat mouth gasket assembly. Actually, this extra displacement is required

ES 2 287 656 T3 to provide functional reliability to the twist lock mechanism.

The downwardly extending projection 80 of the first housing member 36 includes an angular contact surface that exerts a component of radial force on the flat mouth seal assembly 32. The angular contact surface also causes a vertical force component that translates into mounting force. The radial force expands the feature of the contact surface, which is, the peripheral rim 52 of the flat-mouth seal assembly 32. Since the vertical force is only a part of the total normal force, the mounting force is reduced as a function of the angle of the contact surface.

In addition to radial and vertical forces, the joint between the first and second housing elements 36, 38 generates a camming action due to the interaction between the downwardly extending projection 80 and the peripheral rim 52 of the joint assembly 32. flat mouth. The radial movement of the peripheral lip 52 of the flat mouth gasket assembly 32 leaves a small amount of extra displacement for the boss 80 without any negative impact to the sealability of the flat mouth gasket assembly as intended for normal operation. .

In addition to providing the extra displacement, compression of the peripheral flange 52 of the flat mouth seal assembly 32 stores energy that assists in disengagement of the first housing member 36 from the second housing member 38. The stored energy causes the first housing element 36 to move rapidly from the second housing element 38 upon actuation of the lever 78.

More particularly, the coupling of the first and second housing elements 36, 38 is enhanced by the provision of a protrusion 80 extending downward along the lower surface 54 of the first housing element 36 that is shaped and dimensioned to engage the peripheral flange 52 of flat mouth gasket assembly 32. With this in mind, the downwardly extending projection 80 is provided with an inwardly directed tapered section and the peripheral rim 52 is provided with an outwardly tapered section. The inward and outward tapered sections interact to allow clearance between the first and second housing members 36, 38 in a manner that facilitates a fixed bond. By providing opposing tapered surfaces, and in particular by providing an inward tapered surface on the peripheral rim 52 with a small amount of release under pressure, the dimensional tolerances necessary to ensure engagement of the latches are improved.

Proper alignment between the first and second housing elements 36, 38 is achieved by the provision of an alignment pin 82 extending downwardly from the bottom surface 54 of the first housing element 36 and a shaped and sized mating hole 84. to receive the alignment pin 82 formed along the upper surface 50 of the second housing member 38. The provision of the alignment pin 82 and the mating hole 84 ensures that the first and second housing elements 36, 38 can only be mounted in the desired configuration. Optionally, a second pin may be provided to prevent the second latch from engaging. This is an integral part of the design as it is intended for safety. The trocar obturator 14 can only be attached to the first housing member 36 in one configuration and the first housing member 36 can only be attached to the second housing member 38 in one configuration.

As discussed above, the twist-lock mechanism 56 used to connect the first housing element 36 to the second housing element 38 offers a wide variety of advantages. In particular, the twist lock design allows the first housing member 36 to be rigidly attached to the second housing member 38 without risk of the locks "coming off", while allowing the first housing member 36 to be removed very easily. In fact, the holes 76 through which the first and second arms 58 pass extending downwardly from the first housing member 36 prevent any risk of the arms 58 bending deflected. Furthermore, since the force vector of the closure return spring 70 is perpendicular to any disengagement force exerted during use, the force required to attach the first housing member 36 can be treated independently of any specified disengagement force. This is in contrast to typical closure designs in which the arms of the closures are elastically bent to join and detach the outer seal housing. In these types of designs the mounting and dismounting forces are directly related to each other through the bending characteristics of the closing arms. Lastly, the locking mechanism is easily manipulated with one hand.

Relative to the angular contact between the downwardly extending projection 80 of the first housing member 36 and the peripheral rim 52 of the flat-mouth seal assembly 32, this provides reduced mounting force required to bond the first housing member 36 to the second housing element 38. The first housing member 36 can be compressed a greater distance than with a flat gasket and still achieve the same overall strength. This allows design part tolerances to be greater for given compression distance requirements. Furthermore, the elevated nature of the peripheral flange 52 on the flat mouth seal assembly 32 also allows radial deflection, thus further reducing mounting forces. Reinforced gasket set

With reference to Figures 6 to 10, the proximal seal assembly 30 is described. The gasket assembly generally includes a cap 86, a crown 88, bellows 90 used for movement of a radial gasket, a female retaining ring 92, a guard 94, a plurality of reinforced gasket segments 96 that form a body 98 of gasket, a male retaining ring 100 and a lower body 102. The reinforced gasket segments 96 are positioned as described in greater detail below and are mounted between the retaining rings 92, 100 to create a gasket assembly 30 in accordance with the present invention.

More particularly, and with reference to Figures 7 to 10, a reinforced gasket segment 96 is shown. As described in greater detail below5

Subsequently, the proximal seal assembly 30 utilizes a plurality of reinforced seal segments 96 to create a complete seal body 98. Each of the reinforced gasket segments 96 is in the shape of a partial cone, in particular, a cone that extends approximately 225 degrees. While the partial cone shape according to a preferred embodiment of the present invention uses partial cones that extend about 225 degrees, partial cones of other shapes may be used without deviating from the spirit of the present invention. Although cone-shaped gasket segments are described in accordance with a preferred embodiment, flat gasket segments may be employed without departing from the spirit of the present invention.

Each reinforced gasket segment 96 is preferably manufactured from a cross-linked polymer elastomer, such as, but not limited to, polyisoprene or silicone. However, those skilled in the art will appreciate that other materials can be used.

In practice, a series of reinforced gasket segments 96 are used in the manufacture of a gasket body 98 through which an instrument can be inserted. According to a preferred embodiment, four reinforced joint segments 96 are aligned and successively offset 90 degrees from each other. Gasket segments 96 are arranged in a "woven" manner. That is, each gasket segment 96 includes a first side 104 and a second side 106, and the first side 104 of each gasket segment 96 is positioned on the second side 106 of adjacent gasket segment 96 to produce a "woven" assembly. of gasket segments 96.

The reinforced gasket segments 96 are then attached along their peripheral edges 108 to the male and female retaining rings 94, 100 to create a complete gasket body 98. As a result of the partial cone shape of the reinforced gasket segments 96 and the relative rotation thereof, the joined gasket segments 96 create a gasket body 98 in which the individual gasket segments 96 are pushed out with the insertion of an instrument to create an opening for the passage of instruments and elastically moved inward to close the opening after removal of the instruments. The typical deformation of the reinforced gasket segment 96 is shown with reference to FIG. 3. The deformation with insertion of an instrument through it is shown.

As mentioned above, each of the reinforced gasket segments 96 is generally in the shape of a cone with a portion of the cone cut away. The reinforced seal segment 96 includes a peripheral edge 108 attached to a central seal member 110. The peripheral edge 108 is substantially flat, lying in the same plane, while the central joint element 110 is formed in the shape of a section of a cone.

The central gasket element 110 is enhanced by including a reinforcing pad 112 in a central position on the reinforced gasket segment 96. That is, the reinforcing pad 112 is positioned between the peripheral edge and the free edge of the central gasket member 110. More particularly, the reinforcing pad 112 is positioned at the tip of the cone defined by the central gasket element 110, the edges of the reinforcing pad 112 being aligned with the free edge of the central gasket element 110 at the tip of the cone.

The reinforcing pad 112 is integrally formed with the remainder of the center gasket element 110, but has a thickness that is approximately 2.5 times the nominal thickness of the center gasket element 110. In particular, the reinforcement pad 112 of the center gasket element 110 is formed with a thickness of approximately 0.432 mm (0.017 inches), while the remainder of the center gasket element 110 is formed with a thickness of approximately 0.178 mm (0.007 inches). ). Although the thicknesses have been described above according to a preferred embodiment, different thicknesses can be used. The transition between the backing pad 112 and the remainder of the center gasket element 110 is achieved by the tapered section of the center gasket element 110 between the thickness of the backing pad 112 and the remainder of the center gasket element 110. It is further contemplated that the transition could be made without transition zones; that is, with a sharp transition. However, the preferred embodiment has no rising tension portions and allows the joints to seal better. It is also contemplated that the gasket segments may have been made with the flat pad without transition.

As shown in FIG. 7, and in accordance with a preferred embodiment, reinforcing pad 112 is generally formed in a triangular configuration along the center of the arc defined by reinforced gasket segment 96. In particular, the reinforcing pad 112 occupies an arc of approximately 90 degrees along the central joint element 110. As those skilled in the art will surely appreciate, the shape and size of the reinforcing pad 112 can be modified to suit specific needs. However, the reinforcement pad 112 must be shaped and dimensioned to cover an area that is intended for contact with instruments passing through the trocar assembly 10.

The reinforcement pad 112 is located on a portion of the central gasket member 110 that is most likely to have direct contact with surgical instruments when inserted into the trocar cannula 12. According to a preferred embodiment, the reinforcement pad 112 is centrally located; since most surgical instruments will be inserted through the center of the trocar housing 16 and the trocar cannula 12.

It should be noted that, in other embodiments, the angular surfaces that slope from the backing pad 112 relative to the nominal thickness of the center gasket element 110 can be omitted and the backing pad 112 can be smoothly melted into the nominal thickness of the element 110. of central joint by means of continuous curvature.

Low drag forces are desirable between the proximal seal assembly 30 and an insertion instrument. The present proximal joint assembly 30 allows the production of low drag forces without reducing the durability of the joint. This is accomplished by reducing the thickness of the joint in conjunction with the application of a reinforcing pad 112 as described above. As such, the reduction in thickness (in the area not in contact with the instrument) is not accompanied by a reduction in gasket durability as is common with prior art gasket assemblies.

ES 2 287 656 T3

Gasket assemblies incorporating reinforcing pads 112 greatly reduce snagging and tearing of the gasket through insertion or removal of an instrument without requiring additional thickness along gasket segments 96. The greater thickness in the area of ​​the backing pad 112 resists opening in the backing pad 112 where the instrument is in contact with the gasket assembly 98. However, the thin sections of the center seal member 110 surrounding the center reinforcement pad 112 allow for easy stretching of the remainder of the center seal member 110, thus keeping drag forces on moving instruments to a minimum. Since the greatest stress occurs along the opening of the central gasket element 110 when an instrument is present, and in accordance with a preferred embodiment, the reinforced gasket segments 96 must be kept thin in any area that is not in contact with an instrument. This minimizes drag forces.

The effective protection exerted by the present reinforcing pad 112 manifests itself in the proximal seal assembly 30 as follows. For a given deflection of the proximal seal assembly 30 due to initial contact with the tip of an instrument, the area defined by the reinforcement pad 112 of the proximal seal assembly 30 will have relatively low deformation compared to the thinnest part of the element. Center gasket 110 surrounding reinforcing pad 112 due to the difference in thickness between reinforcing pad 112 and center gasket element 110. This differential in strain is greatest at the opening of the proximal seal assembly 30, where the overall strains are highest. When a force is applied to the backing pad 112 due to contact with an instrument, the increased thickness of the backing pad 112 will resist opening, while the thin cross-section of the remainder of the central gasket element 110 that is not covered by the reinforcement pad 112 will allow the reinforcement pad 112 to deflect distally in a simple manner allowing the instrument tip to roll to the center of the assembly. 30 of proximal joint. The tear strength of the reinforced gasket segment 96 is greatly increased compared to prior art gasket segments.

The reinforcement pads 112 allow the reinforced gasket segments 96 to protect themselves from sharp instruments independently of other peripheral protection devices. This protection is integral with the reinforced joint segments 96 themselves. Also the addition of reinforcement pads 112 in strategic locations (away from high stress areas located directly at the point of contact of the probable sharp instrument) allows the reinforcement pads 112 to protect against puncture with little or no impact on the board performance. They do not increase the instrument insertion forces or the maximum instrument drag forces. It is contemplated that the use of reinforcing pads 112 could expand beyond their placement at a central location, thus offering some impact on instrument insertion forces and maximum instrument drag forces. However, due to the nature of gasket segments 96 and their greatly reduced stress relative to conventional lip seals, this impact will likely provide a design that will easily outperform conventional gasket assemblies. Woven joint protector

Although gasket body 98 is formed with reinforcing pads 112 as described above, it is still desirable to provide proximal gasket assembly 30 with a shield 92, as best shown in Figure 13. Shield 92 is placed directly over gasket body 98. Referring to Figures 6 and 11 through 13, shield 92 is comprised of multiple overlapping shield segments 114 assembled in a woven arrangement to provide a complete shield 92. By forming the shield 92 in a woven arrangement, additional protective material is added (as a result of the overlapping arrangement) so that an additional surface area of ​​the gasket body 98 can be protected when the protective segments 114 are separated when inserted. an instrument on the board.

Since the present proximal seal assembly 30 has a small central opening that expands in a reliable and convenient manner, the shield 92 must be formulated to close the gaps between the shield segments 114 when an instrument is passed through the shield 92 and the shield. gasket body 98. This requires the addition of material across the opening of shield 92.

Additional material is added to shield 92 by weaving a plurality of shield segments 114. By weaving the shield segments 114, extra material is added to the shield 92 so that each component of the shield is flared while still allowing the shields to fit within the conical profile of the gasket. The extra material is wrapped behind the protective segment 114 to one side of each protective segment 114. This extra material is not visible when viewing the protective segments 114 from above without an inserted instrument.

Protective segments 114 are made from molded elastomer, eg, pellethane ("thermoplastic polyurethane elastomer"). However, the protective segments 114 are not intended to be limited simply to elastomers, but the protective segments 114 may be made from any type of material that contains the properties and characteristics required for the function described herein.

In particular, four guard segments 114 are arranged to create guard 92. Although four guard segments 114 are used in accordance with a preferred embodiment, guard 92 may ultimately be formed with different numbers of guard segments 114.

Each protective segment 114 is semi-circular when viewed from above and generally in the shape of a partial cone. Each of these guard segments 114 includes a substantially round peripheral edge 116, a support wall 118 extending from the peripheral edge 116, and a cone-shaped guard element 120. The cone-shaped shield element 120 opposite the support wall 118 and the peripheral edge 116 defines an edge 121 in a straight line.

The cone-shaped protective element 120

ES 2 287 656 T3 spans an arc of approximately 180 degrees, while the support wall 118 and peripheral edge 116 span an arc of approximately 120 degrees along the center of the cone-shaped shield element 120. As will be discussed in greater detail below, the limited arc spanning peripheral edge 116 and support wall 118 reduces unwanted forces as instruments are moved past proximal seal assembly 30.

The outer peripheral edge 116 is adapted to be positioned within the first housing member 36. The outer peripheral edge 116 further includes a series of openings 122 that function as attachment means for the protective segments 114. As will be apparent from the following description, the use of multiple guard segments 114 defining an arc of approximately 180 degrees results in a reduction in hoop stresses by providing a guard 92 comprised of a series of inwardly bending guard segments 114. and out easily when instruments are inserted through it.

Each protective segment 114 includes a first section 124 and a second section 126 that define opposite sides of the protective segment 114. The four individual shield segments 114 are combined in a woven arrangement to create a complete shield 92 that fully protects the underlying gasket body 98. That is, the shield 92 is mounted by placing the first section 124 of a first shield segment 114 over the second section 126 of a second shield segment 114. The first section of the second protective segment 114 is then placed over the second section 126 of a third protective segment 114, the first section of the third protective segment 114 is placed over the second section 126 of a fourth protective segment 114 and the first section 124 of the fourth protective segment 114 is placed over the second section 126 of the first protective segment 114, much like the end flap of a box lid is folded.

Ultimately, protective segments 114 are held together through the application of crown 88 and female retaining ring 94. Retainers are well known to those skilled in the art and a variety of retainers can be used.

As will be readily appreciated by those skilled in the art, the movement of the cone-shaped shield elements 120 with respect to the peripheral edge 116 and the support wall 118 is subjected to resistance based on the various orientations of the connected components. Thus, the cone-shaped shield elements 120 could be susceptible to buckling when the instruments are moved through the proximal joint assembly 30.

This resistance to movement is minimized due to the limited arc of peripheral edge 116 and support wall 118 as discussed above. Furthermore, resistance is further minimized by forming a central groove 128 with peripheral edge 116 and / or supporting wall 118. This slot 128 has the function of reducing buckling since the shielding elements 120 can move the same distance with less resistance.

By the fabric of shield 92 additional material can be added to each shield segment 114, while still allowing the distal end of shield 92 to fit within the apex of cone-shaped gasket body 98. This is achieved by causing the extra material added to the protective segments 114 to wrap behind the protective segment 114 adjacent thereto. This extra material allows for improved coverage of the joint body 98, especially when instruments are inserted at an angle to the proximal joint assembly 30. Finally, knitting the shield 92 has minimal effect, if any, on the pulling force of the instrument as it moves in and out of the proximal joint assembly 30. This is a result of the fact that the protective segments 114 easily move relative to each other.

In practice, and due to the extra material added to each guard segment 114, when an instrument is inserted into guard 92, guard segments 114 expand, exposing additional guard material positioned behind adjacent guard segments 114. This additional material continues to cover the gasket body 98 as the protective segments 114 are bent relative to each other. The less material from the gasket body 98 is exposed to the inserted instrument, the better the protection offered by the present shield 92. Although the present shield 92 offers good gasket protection, additional shield segments 114 may be added, although they could cause increased on the drag forces of the instrument. This can be balanced, however, by decreasing the thickness of the shield segments 114 to make them more flexible or by adding lubricant to the shield segments 114 and / or the gasket body 98. Flat manhole gasket set

As mentioned above, a flat mouth seal assembly 32 is housed within the second housing member 38. With reference to Figures 14 to 16, the flat mouth seal assembly 32 in accordance with a preferred embodiment of the present invention is described. The flat mouth gasket assembly 32 includes first and second gasket bodies 130, 132 extending from a circumferential flange member 134 shaped and sized to mount within the second housing member 38.

Each of the first and second gasket bodies 130, 132 includes an upper surface 136, 138 and a lower surface 140, 142. The upper surface 136, 138 and the lower surface 140, 142 are generally mirror images since the first and second gasket bodies 130, 132 maintain a substantially consistent thickness along their entire length with the exception of the reinforcing rib a along the upper surface 136, 138.

The first and second joint bodies 130, 132 are mounted within the trocar housing 16 for movement when an instrument is passed through. With this in mind, the proximal end of each first and second seal body 130, 132 is coupled to the trocar housing 16 via a circumferential flange 134, while the distal ends of the first and second seal body 130, 132 intersect to define a stop face 144. Stop face 144 is generally positioned in the center of trocar housing 16 to allow passage of an instrument therethrough, whereas in the absence of such an instrument,

The abutment face 144 is closed by the elasticity of the first and second bodies 130, 132 when they are urged under the pressure generated from the cavity of the body in which the trocar assembly 10 is placed. For example, driven under the pressure of abdominal insufflation gas pressure. This pressure causes the flat-mouth seal assembly 32 to move to a closed position with the distal ends of the first and second seal bodies 130,132 in contact.

As will certainly be appreciated by those skilled in the art, gasket bodies 130, 132 can be formed with ribs (not shown) on top surface 136, 138 so as to improve the stability of gasket bodies 130, 132 when in contact. with an instrument. The ribs also provide a path that the instruments travel through as they pass through the flat-mouth seal assembly 32. The ribs also decrease friction as the instruments pass through the flat-mouth seal assembly 32, because it provides less surface area that an instrument can traverse, and thus greater contact pressure can be applied between the seal and the instrument.

The first and second seal bodies 130, 132 will be described with reference to the first seal body 130. Those skilled in the art will appreciate that the first and second seal bodies 130, 132 are identical and that the following descriptions refer to the second seal body 132. The joint body 130 is formed with a first section 148 and a second section 150 oriented angularly to each other and a transverse plane 146 extending through the circumferential flange 134. In particular, transverse plane 146 is substantially perpendicular to the longitudinal axis extending through flat mouth seal assembly 32. The first and second sections 148, 150 extend from a proximal end of the seal body 130 respectively towards a distal end of the seal body 130. Thus, the first section 148 is positioned adjacent the proximal end of the gasket body 130 adjacent the wall of the circumferential flange 134 and the trocar housing 16. The first section 148 moves only slightly when an instrument is inserted through it. The second section 150 is positioned adjacent the distal end of the gasket body 130 and adjacent the abutment face 144. The second section 150 moves freely when an instrument is inserted through it.

In general, the first and second sections are at angles between 0 degrees and 90 degrees to the transverse plane. Assuming that the transverse plane 146 is in a horizontal plane, the first section 148, beginning at the proximal end of the joint body 130, is oriented at approximately a 30 degree angle with respect to the horizontal plane in which the joint lies. plane 146 transverse. The second section 150, which extends to the distal end of the joint body 130, is posteriorly oriented at an angle of 45 degrees with respect to the horizontal plane. Those skilled in the art will appreciate that the angles described above can be varied. The angles chosen are based on a balance between the durability of the joint bodies (improves with higher angles since the probability that an instrument will hook the tip to the joint, that is, that it opens, is less likely with angles greater) and the height of the joint (greater angles provide greater height). For example, it is contemplated that the second section 150 may be formed at an angle of from about 40 degrees to about 50 degrees, while providing the numerous benefits contemplated by the present flat mouth seal assembly 32. The height or profile of the flat mouth seal assembly 32 is important since reductions in size allow for improved instrument access because, consequently, the length of the trocar housing 16 can be made shorter. Smaller housings provide surgeons with greater access into the body cavity and are therefore highly desirable.

Although a preferred embodiment as described above uses a first and a second section 148, 150, additional sections can be used without departing from the spirit of the present invention. Similarly, the present flat mouth gasket bodies 130,132 can be constructed with an infinite number of angles, that is, with a surface of continuous curvature.

Regardless of the exact wall construction used, the wall angle should be kept low (eg, 30 degrees) when instruments are not generally contacted with gasket bodies 130, 132 of flat mouth gasket assembly 32 and increase to a high value (eg, 45 degrees) when the instruments are routinely contacted with the wall surface of the joint bodies 130, 132.

By orienting the first and second sections 148,150 in this manner, that is, by varying the angles of the wall along the extent of joint bodies 130, 132, tear resistance is improved without adjusting the overall height of joint assembly 32. flat mouth seal. By providing a low wall angle in the position where instruments do not routinely contact seal bodies 130, 132, the overall height of flat mouth seal assembly 32, and ultimately assembly 10, can be minimized. trocar, while the proper function of the joint is satisfied. Applying a high wall angle at the location where instruments typically contact seal bodies 130, 132 minimizes the normal forces that contact flat-mouth seal assembly 32 and consequently , the potential for tearing of the flat-mouth seal assembly 32 is minimized.

As discussed above, the height of the trocar sleeve 44 is a critical issue due to its impact on ergonomics. At the same time, the sealing, durability and drag functions of the flat-mouth gasket must be balanced against the need for minimized height of the trocar sleeve 44.

In order to provide a superior design in accordance with the present flat mouth gasket assembly 32, the height of the flat mouth gasket assembly 32 is minimized by using two wall angles. The wall angle along the first section 148 is low to minimize height. With a given critical diameter, the wall angle becomes steeper in the second section 150. This sloping wall provides a lower angle of attack relative to an inserted instrument to maximize durability. At the same time, the sealing function is improved due to the

ES 2 287 656 T3 higher closing forces of the abdominal gas pressures acting on the second section with the lower angle of attack due to the inclined wall, compared to the angle of the first section 148.

Despite the advantages that the multi-angle design offers, the forces between the flat-mouth seal assembly 32 and the instrument must still be further minimized. This is achieved through wall thickness, rib geometry, and surface coating fit. Lower drag forces are desirable to reduce the effort required by a surgeon when inserting or removing instruments from a trocar sleeve 44. Reducing the effort required is desirable to allow insertion or removal of an instrument with one hand. This also reduces the possibility of a sleeve 44 being removed from a patient into which the trocar assembly 10 has been inserted.

As discussed, and while 30 and 45 degree angles are used, since larger diameter instruments are required, larger diameter flat mouth gasket assemblies 32 will also be required. Since space is at a premium in valve applications, especially for flat mouth seal assemblies 32 when used in trocar assemblies, a minimum height is highly desirable. The durability of the gaskets is paramount which is why a forty-five degree angle is used to minimize tearing of the gasket bodies 130, 132 while the instruments are inserted or removed.

According to a preferred embodiment, flat mouth seal assembly 32 is an elastomer or cross-linked polymer such as, but not restricted to, polyisoprene or silicone.

Locking set of an endoscope

As discussed above in the background of the invention, it is often desirable to lock an endoscope in position relative to a trocar assembly 10, particularly an obturator 14. An endoscope locking assembly 152 of this is provided. type according to the present invention and is shown in Figures 3, 4 and 25. Endoscope locking assembly 152 generally includes a cam mechanism that retains an endoscope within trocar sleeve 44 and / or obturator 14 during insertion of trocar assembly 10. The mechanism uses a cam to compress an elastomeric block 154 against the endoscope. The elastomeric block 154 then holds the endoscope firmly to prevent unwanted movement of the endoscope when the surgeon is viewing the tissue layers during insertion of the trocar assembly. Cam mechanism provides the ability to retain the endoscope while resisting both torsional and axial loads, provides acceptable endoscope retention after repeated pulling of cam lever 156, provides low ergonomic forces to actuate cam lever 156 , provides compatibility with a wide range of endoscope sizes, facilitates intuitive use, and has long-lasting shelf life stability.

The cam mechanism that retains the endoscope within a trocar assembly 10 uses a cam surface 158 to compress the elastomeric block 154 against the endoscope. The elastomeric block 154 then holds the endoscope firmly to prevent unwanted movement of the endoscope when the surgeon is viewing the tissue layers during insertion of the trocar assembly.

The lock assembly 152 includes a housing 160 having a tube 162 extending therefrom. Tube 162 is aligned with an opening extending therefrom. The tube is formed with a sharp tip and can be used as an obturator in accordance with the present invention. Tube 162 and aperture are shaped and dimensioned for extension of an endoscope therethrough. In addition, tube 162 is shaped and dimensioned to extend through trocar cannula 12 so that locking assembly 152, including tube 162, can be selectively attached to trocar sleeve 44 for use with an endoscope.

Attachment of the locking assembly 152 to the first trocar housing element 36 is accomplished by coupling fasteners 164, 166 formed on both the bottom of the locking assembly housing 160 and the upper surface 168 of the first housing element 36. Locks 164, 166 allow for selective attachment and release of block assembly 152 to trocar housing 16. Although a specific closure structure is described in accordance with a preferred embodiment of the present invention, other closure structures may be used without departing from the scope of the present invention.

Lock assembly housing 160 includes a cam-based locking mechanism. The locking mechanism is comprised of a cam lever 156 and an elastomeric block 154. Cam lever 156 includes a first end 170 that is pivotally attached to housing 160 and a second free end 172 that is adapted for actuation by the user. In practice, the cam lever 156 is freely movable between a locking position in which the cam lever 156 is rotated inward and a release position in which the cam lever 156 is rotated outward.

The action of the cams in accordance with the present invention is provided by a cam surface 158 adjacent the first end 170 of the cam lever 156. Camming surface 158 is shaped and dimensioned to engage elastomeric block 154 to selectively lock an endoscope within locking assembly 152. With respect to the elastomeric block 154, it is housed within the housing body 160 of the locking assembly and includes a forward concave wall 174 shaped and sized to engage an endoscope passing through the housing opening. The elastomeric block 154 further includes first and second side walls 176, 178, wherein each side wall 176, 178 includes a notch 180 for engagement with a channel 182 formed within the housing body 160. Channel 182 and notch 180 interact to allow lateral movement of elastomeric block 154 in a manner that will be described in greater detail below. Housing 160 further includes upper and lower retention elements 184, 186 to securely prevent upward or downward movement of elastomeric block 154 within housing 160. Finally, elastomeric block 154 includes a rear wall 188 opposite concave wall 174 lead. Rear wall 188 is shaped and dimensioned to engage cam surface 158 of cam lever 156.

ES 2 287 656 T3

Elastomeric block 154 and cam surface 158 are shaped to eliminate strong contact, and in particular to eliminate any contact, between elastomeric block 154 and cam surface 158 until such time as the endoscope is positioned with the aperture. of housing 160 of the lock assembly. As will be described in greater detail below, when an endoscope is positioned within the opening of the housing 160 of the locking assembly, the elastomeric block 154 moves toward the cam lever 156 to a degree such that the elastomeric block 154 approaches to cam surface 158 to lock the endoscope within the opening once the cam lever has been actuated.

In practice, lock assembly 152 is used as follows. Elastomeric block 154 seats within lock assembly housing 160 below cam lever 156, which can be either open or closed during long term storage. The elastomeric block is purposely not in contact with the cam lever 156 at this point to avoid any loading on the elastomeric block 154 that could affect the performance of the lock assembly 152 after long term storage. The surgeon then opens the cam lever 156 if it was originally closed. An endoscope is inserted into locking assembly 154. The endoscope strikes a beveled surface 190 on the concave wall 174 of the elastomeric block 154. This raises the elastomeric block 154 up near the cam lever 156. The elastomeric block 154 then rests on the endoscope for the remainder of its use. The cam lever 156 is then actuated, which compresses the compressible reach lock on the endoscope. The compliance of the elastomeric block 154, along with its high coefficient of friction, allows the locking assembly 152 to be compatible with a wide range of endoscope sizes while minimizing ergonomic force requirements. Excessive axial or lateral movement of the elastomeric block 154 is restricted by surrounding components 182, 184, 186 that limit its movement when axial and torsional loads are applied to the endoscope. This restriction, along with a cam design in the center, prevents the cam lever from accidentally unlocking itself. After the trocar assembly 10 has been inserted into the patient, the cam lever 156 is opened and the endoscope is removed. The elastomeric block 154 then returns to its original position in the locking assembly 152 if the surgeon wishes to re-insert the endoscope later. The conformal elastomeric block 154 has sufficient rigidity to return to its original shape after the load has been removed from the cam lever 156, thus providing an acceptable endoscope retention force over the course of multiple actuations of the lever. Trocar Sleeve and Shutoff Valve Construction

As mentioned above, trocar sleeve 44 is comprised of a trocar housing 16 and a trocar cannula 12 extending from trocar housing 16. Trocar assembly 10 also includes a shutoff valve 192 to allow and prevent passage of insufflation fluid, eg, carbon dioxide, through a system of flexible tubing within a portion of the trocar housing and cannula. 12 of trocar.

With reference to the figures, trocar cannula 12 and trocar housing 16 are mechanically fitted together to form trocar sleeve 44. At least a portion of the trocar cannula 12 is seated within a base 38b of the second housing element of the second housing element 38 with a second housing element cover 38a that sits on the trocar cannula 12 to secure the al minus a portion of the trocar cannula 12 within the base 38b of the second housing member.

Trocar cannula 12 is sized so that when trocar obturator 14 extends fully through and beyond, insufflation fluid, which passes through shutoff valve 192 and housing 16 of bartering, it can pass through an annular opening produced between trocar cannula 12 and trocar obturator 14 by the size slightly greater than the internal diameter of trocar cannula 12 relative to the external diameter of the hollow shaft of trocar obturator 14.

The present invention provides a mechanism for mechanically mounting trocar cannula 12, trocar housing 16, and shutoff valve 192 without the need for adhesive and / or curing techniques. In particular, the second housing member 38 of the trocar housing 16, the trocar cannula 12, and shutoff valve 192 are formed as separate components that can be assembled in a convenient and reliable manner.

More particularly, and with reference to Figures 17, 18, 19 and 20, a preferred embodiment of the mechanically assembled trocar sleeve 44 is described. The trocar sleeve 44, when fully assembled, comprises a shutoff valve 192, a second housing element 38 comprised of a cover 38a of the second housing element and a base 38b of the second housing element, and a trocar cannula 12 . The various components of the trocar sleeve 44 are mechanically assembled by fitting the components together in a manner that is described in greater detail below. Briefly, trocar cannula 12 fits within base 38b of the second housing member with shutoff valve 192 positioned therebetween. Second housing element cover 38a fits over shutoff valve 192, second housing element base 38b, and trocar cannula 12 to retain the various components together and provide a surface on which the first element can be selectively mounted. 36 accommodation.

With respect to the specific components that make up the trocar sleeve 44, the shutoff valve 192 includes alignment flaps 194, a fluid port 196, and a valve lever 198. Valve lever 198 includes a stop lock 200. The cover 38a of the second housing element includes a hexagonal bore 202, a cover flange 204, and a cover gasket 206 of the second housing element. The base 38b of the second housing member includes friction posts 208, vanes 210, a housing flange 212, a clearance 214 for the shutoff valve 192, and alignment fins 194. The base 38b of the second housing member further includes alignment ribs 216 and a closure face 218. Trocar cannula 12 includes nozzle 220 of

ES 2 287 656 T3 entrance, alignment tabs 222, and a housing gasket 224.

In practice, the shut-off valve 192 is inserted into the gap 214 in the base 38b of the second housing member. The trocar cannula 12 is inserted through the base opening 38b of the second housing member. Alignment tabs 222 abut blades 210 securing trocar cannula 12 in a desired orientation relative to second housing element base 38b once trocar cannula 12 is inserted into second element base 38b. accommodation.

Cover flange 204 mates with housing flange 212. The cover rim 204 also serves to hold the valve lever 198 on the shutoff valve 192, as well as to hold the shutoff valve 192 in place with the valve lever 198.

The valve lever 198, in a maximum flow tolerance position, ie fully open, has the stop closure 200 abutting the closure face 218 of the base 38b of the second housing member. This means that an operator of valve lever 198 can detect when valve lever 198 is in a fully open position by abutting closure face 218 and valve lever 198 remains in the fully open position. The operator does not have to guess that the valve lever 198 is in the fully open position, and that the valve lever 198 remains in the fully open position.

The construction of the trocar assembly 44 eliminates the need for adhesives to bond the shutoff valve 192 and the cover 38a of the second housing element, and the base 38b of the second housing element and the trocar cannula 12. This is an advantage over the prior art.

With reference to Figures 21 and 22, an alternative trocar sleeve 44 'is described. According to this alternative embodiment, the trocar sleeve 44 'includes a shutoff valve 192', a cover 38a 'of the second housing element, and a base 38b' of the second housing element. The trocar sleeve 44 'also includes a trocar cannula 12' which is substantially similar to the trocar cannula 12 described in accordance with the previous embodiment.

The shutoff valve 192 'comprises a valve tube tapered locking extension 226', a friction post 228 ', and a valve lever 198'. The base 38b 'of the second housing member comprises an extension gap 230', and a hexagonal bore 232 'in the friction post.

The tapered locking extension 226 'of the valve tube of the shut-off valve 192' is locked within the extension gap 230 'of the base 38b' of the second housing member. The friction post 228 'of the shut-off valve 192' fits within the hexagonal bore 230 'of the friction post of the base 38b' of the second housing member, fixing the vertical alignment of the shut-off valve 192 'with respect to to the base 38b 'of the second housing element.

With reference to Figures 23 and 24, a further embodiment is described. According to this further embodiment, the trocar sleeve 44 "comprises a cover 38a" of the second housing element, a base 38b "of the second housing element, and a shut-off valve 192". The trocar sleeve 44 "also includes a trocar cannula 12" which is substantially similar to the trocar cannula 12 described in accordance with the previous embodiment.

The shut-off valve 192 "comprises a locking groove boss 234", a valve tube extension 236 ", and a locking groove 238". In addition, the cover 38a "of the second housing element includes a locking tab 240". The base 38b "of the second housing member also comprises a valve tube extension opening 242" and a protrusion gap 244 ". The valve tube extension 236 "of the shutoff valve 192" is inserted and locked, by friction fit or tapered block, into the base valve tube extension opening 242 "38b" of the second element. accommodation. The locking groove boss 234 "of the closure valve 192" locks within the boss gap 244 ". This serves to help secure the shutoff valve 192 "to the base 38b" of the second housing member.

As mentioned above, shutoff valve 192 is mechanically coupled to trocar sleeve 44 by tapered surfaces shaped and sized for frictional engagement. Thus, the outlet tube 250 of the shutoff valve 192 is formed with a tapered locking surface along the outside of its distal end. Similarly, trocar cannula 12 is formed with an inlet nozzle 220, adapted for fixed engagement with the tapered locking surface of outlet tube 250 of shutoff valve 192. The mechanical feature of the tapered locking element includes a 2.0 degree +/- 1.0 degree angle self-retaining, which is firmly seated within the entry nozzle 220 of the trocar housing. The result of this mechanical connection is frictional resistance to linear and rotational breakout forces.

The mechanical lock discussed above can be enhanced by providing a dual redundancy feature. For example, the tapered locking feature may be provided with a post and a hexagonal socket interlocking device, a tongue and groove interlocking device, and / or a snap interlocking device.

Furthermore, and in accordance with the embodiment described above with reference to Figure 18, rotation of the shut-off valve 192 is minimized by the inclusion of a retaining pin 204 located on the cover 38a of the second housing element that extends downwardly into of the aperture 256 formed in the top of the valve lever 198. The detent pin 204 stabilizes the shut-off valve 192 and prevents rotation when the valve lever 198 of the shut-off valve 192 is actuated.

As mentioned above, the trocar sleeve includes a shutoff valve 192. Shutoff valve 192 is mounted within a recess formed in trocar sleeve 44. As such, the shut-off valve 192 recessed within the outer surface of the base 38b of the second housing member, and ultimately the trocar housing 16. Valve lever 198 is further positioned above shutoff valve body 192; that is, the valve lever 198 used to actuate the

ES 2 287 656 T3 shutoff valve 192 is positioned on top of shutoff valve 192 rather than underneath such as with trocar assemblies currently on the market. By positioning the valve lever 198 above the lowered closure valve 192, the present trocar assembly 10 provides for removal of the closure valve 192 from a potential view of obstruction when the valve lever 198 is simultaneously placed in an extremely high position. accessible.

Several advantages are achieved by recessing the shutoff valve 192 within the body of the trocar sleeve 44. First, this orientation minimizes obstructions caused by users holding the shutoff valve 192 of trocar assembly 10 for insertion. Thus, a more comfortable grip is provided when the shutoff valve 192 does not protrude beyond the surface of the trocar housing 16. The present low profile shutoff valve structure 192 further helps prevent compromising desired hand positions. The present orientation of shutoff valve 192 also helps prevent accidental manipulation during procedures. Accidental manipulation by movement of the trocar sleeve 44 in contact with a patient is a common event that results in deflation of the body cavity and can lead to frustrating and even dangerous situations when the practitioner's field of vision is compromised.

The advantages are further enhanced by forming the valve lever 198 with a curved surface that substantially conforms to that of the trocar housing 16. In addition, the longitudinal axis along the handle portion of the valve lever 198 is offset from the pivot point about which the valve lever 198 rotates so as to enhance the recess of the shutoff valve 192. Controlled rotation of valve lever 198 of shutoff valve 192 is accomplished through placement of shutoff valve 192 within a recess formed in trocar sleeve 44, more specifically, trocar housing 16. Specifically, and with reference to Figures 17, 18, 19, and 20, valve lever 198 includes a stop latch 200 located on valve 198 that provides tactile feedback when valve lever 198 is in the open position, i.e., the through holes located on the valve lever 198 and the valve body 199 are aligned. The design feature is reminiscent of a cantilever beam located at the end of the valve lever 198 opposite the user end.

When valve lever 198 is rotated from closed to open position within trocar assembly 10, cantilevered rotational stop closure 200 contacts trocar housing 16 providing tactile feedback that lever 198 valve is in the fully open position. In the fully open position, the valve lever 198 and the through holes of the valve body 199 are aligned allowing the flow of CO.₂ optimum.

The cantilevered rotational stop closure 200 feature provides the surgeon with tactile feedback to ensure that the closure valve 192 is in the open position. This will provide the optimal flow of CO2 flow through the surgical box.

As those skilled in the art will appreciate, control of valve lever 198 by cantilevered rotational stop closure 200 assists in alignment of closure valve 192 through through hole 196. Misalignment of through holes 196 is typically caused by a lack of tactile feedback to the surgeon that valve lever 198 is in the fully open position.

In addition, a reinforcing pleat 264 is located at the rear of the cantilevered rotational stop closure 200 to prevent excessive rotation of the valve lever 198 by bending the valve lever 198. This can be seen in Figures 17 and 18. Excessive rotation would cause misalignment of the through holes.

As will be appreciated by those skilled in the art, the design described above offers many advantages over prior art assemblies. The separate trocar cannula 12 described above provides interchangeable external housing capabilities. Thus, the outer shape of the industrial design can be easily changed and updated without changing the internal structure of the trocar sleeve. In addition, the assembly of trocar cannula 12 to trocar housing 16 attachment system eliminates the need for ultrasonic welding. The present assembly procedure makes the device stronger by molding the trocar cannula 12 in one piece. As will be appreciated by those skilled in the art, prior designs used ultrasonic weld joints to mount the trocar cannula 12 in the trocar housing 16. The present mounting structure eliminates the use of such gaskets and, therefore, does not provide any opportunity for failure of the ultrasonic welded joints.

In addition, trocar housing 16 is provided with shock ribs 266 along its inner surface. These shock ribs 266 center the trocar cannula 12 within the trocar housing 16. They can also have small variations in tolerances making the size of the trocar cannula 12 less important during manufacture and allowing inherent variations during the molding process.

Shock ribs 266 further prevent rotation of trocar cannula 12 within trocar housing 16. This is accomplished when the shock ribs 266 extend into the sides of the trocar cannula 12, thereby preventing relative rotation between the trocar cannula 12 and the trocar housing 16.

Since the trocar housing 16 and trocar cannula 12 are fairly simple in construction, the molding procedure is simplified by eliminating excessive center details in the injection molding tool. Furthermore, the assembly of the system is easy compared to previous designs since all the components that make up the sleeve assembly can be assembled in a downward fashion.

With respect to the shut-off valve 192, the tapered lock with dual redundant locking features helps prevent the shut-off valve 192 from pulling out of the trocar sleeve 44. Additionally, the tapered lock provides a watertight assembly without the use of adhesives or welding. In addition, the shut-off valve 192 is provided with several locking surfaces that prevent rotation.

ES 2 287 656 T3 of the shut-off valve 192, for example, post and socket, tongue and groove, fins on ribs, etc. In addition to the features of the tapered lock, the wings are trapped behind the trocar housing 16, eliminating the ability to remove the closure valve 192 from the trocar sleeve 44. In addition, the shock ribs 266 are used to hold the wings firmly on the trocar cannula 12. Finally, the low profile shutoff valve 192 construction with a valve lever 198 positioned over shutoff valve 192 allows for alignment of shutoff valve 192 to provide optimal airflow and offers users tactile feedback. to optimize alignment.

Although the preferred embodiments have been shown and described, it will be understood that there is no intention of limiting the invention by such description, but rather, it is intended to cover all modifications and alternative constructions that are within the scope of the invention as defined in the appended claims.