Releasable connection of two tube shaft instruments or instrument parts

The invention relates to a bayonet coupling for releasable Connecting two tubular shaft instruments or instrument parts, with a bayonet guide having bayonet sleeve (Female part) on one instrument or instrument part and a bayonet insert (male part) at the other instrument or -instrumententeil, and having a lock for locking the closed bayonet coupling.

Such bayonet coupling is known from DE 43 07 539 A1 known.

In medical technology, there is an increasing need for instru instruments and in particular to tubular shaft instruments by few simple steps are separable, the instruments after a clean operation and sterilize. Furthermore, have in medical Found module construction input, for example, can of tubular shaft instruments with scissor-like handles on distal end different instrument parts such as cutting, Grasping forceps or the like are mounted.

In minimally invasive surgery it is often necessary, an endoscope, a trocar, a pliers, a pair of scissors or a use another instrument in a shaft, for example a Universal shaft, can be a trocar sleeve or the like. It is thereby required that the instrument associated with the shaft connected in use fixed to the shaft, and if necessary can again be easily solved.

To prepare these solid compound is a clutch provided. Typically, these couplings are as bayonet couplings formed, that is at one of the tubular-shafted instruments or -instrumententeile is a bayonet guide containing Bayonet sleeve (female portion) is provided, into which a bayonet will use (male part) is inserted or screwed can.

Thus during handling by turning the parts verkuppelten not solved relatively the bayonet coupling again is, interlocks are provided.

In the aforementioned DE 43 07 593 A1, the bayonet sleeve provided at the distal end of a tubular shaft pliers. The bayonet insert is at the distal end portion of a rod shaped actuating element provided at the distal end the forceps jaws carries. The proximal end of the rod The actuating element is for connection to a mobile Grip element of the scissors-like or otherwise listed Handle. When Matchmaking these two parts is the proximal end of the rod-shaped actuating element distal inserted into the shaft and pushed therethrough until the Bayonet insert comes with the bayonet sleeve engaged. After this the bayonet insert in the bayonet guide of the bayonet sleeve was inserted and rotated, the two components are locked in this position with one another. These are the proximal painting the end of the rod-shaped actuating element two axially extending flattenings provided in the radially Clamping elements are inserted, in a spring ring the clamping position are maintained. The clamping members prevent relative rotation between the shaft and rods shaped actuator.

This lock is difficult to handle and requires dimensionally accurate machining the rod and the sleeve at the proximal End.

Due to the fact that the actual bayonet coupling is disposed at the distal end, the locking but at the proximal end of the tubular shaft instrument, able to Tubular shaft instrument acting torques nevertheless loosening causing the clutch. The rod-shaped actuator comprises at conventional pliers diameter in the range of a few Millimeters, however, lengths ranging from 20 cm and more. That is, the clutch is located approximately in an axial Distance of 20 cm for locking. Torques can now such a twist of the long and thin rod-shaped cause the actuating element, that the distal end of the rod is rotated relative to the extent locked proximal end, that the clutch releases.

Such torques act on instruments, if, for example with the working instrument at the distal end portion of a piece of fabric, for example, cartilage, and detected by closing and turning the Instrument the detected piece of tissue to be removed.

From DE 43 23 093 A1 discloses a similar surgical forceps known, in which also the distal end of the bayonet coupling is provided at the proximal end of the lock. The Locking is accomplished such that the proximal end the rod-shaped actuating element is an axially he stretching spring element is provided, which in a longitudinal slot at the proximal end of the shaft engages. Here too , a torsion of the rod-shaped actuating element to result that the clutch is released.

Such loosening can the patient have fatal consequences, because the instrument can no longer be actuated, and then dissolves in the patient's body into two parts.

It is therefore an object of the present invention, a bayonet coupling of the initially mentioned kind to the effect weiterzuent wrap that the lock is safe, especially high Torques acting on the bayonet joint record, can.

According to the invention the object is achieved by the fact that the Locking a along the bayonet sleeve sliding Verrie gelungsstück having that turned with the bayonet sleeve translated bayonet use in its final position immediately in locking engagement occurs and the bayonet insert against rotation blocks, and, for releasing the lock, bayonet insert is moved away.

The lock is now no longer off OWNER union bayonet coupling, but is submitted directly to the Coupling. Thus Entkupplungen are by torsional of devices between bayonet coupling and locking excluded. Due to the fact that the Lock directly, ie directly with the bayonet insert comes into locking engagement, to very high torques be included. Characterized in that the locking piece merely axially, ie along the bayonet sleeve is slidably and with the bayonet insert in its final rotational position in blocking Engages, is excluded that the bayonet insert can unscrew from the final rotational position. This would be Provided that the bayonet connection triggers, i.e. the Bayonet insert must first rotated by a certain amount be, but this is now effectively disabled.

In addition, the closing and the release of the coupling easy to accomplish in that the locking piece axially along the bayonet sleeve is moved, either in Direction of the locking position for locking, or in the opposite direction to release the lock. The Bayonet coupling including lock is a compact device, that is, all components are on the region of the bayonet coupling limited. This also opens up a very flexible arrangement the bayonet coupling, either at the distal or proximal End of a tubular shaft instrument or intermediately according to taste.

The clutch is now available regardless of whether a rod shaped actuator as described above exist or not. The now proposed clutch works whatever components of other function, thus wesent Lich universal and safe use.

Thus, the object is completely achieved.

In a further embodiment of the invention is the INTERLOCKS ment piece is urged by the force of a spring, which the Locking piece in the locking engagement with the bayonet use presses.

This feature has the advantage that the locking piece is permanently pressed into the locking position, thus closed clutch is securely locked off. to release the clutch has the locking piece against the force of Spring are first deducted from the bayonet used only it can be rotated. This is by an easy-to manageable displacement movement along the tubular shaft instrument without other manipulations are necessary, as for example, disassembly of the shaft or disassembly of grip elements.

In a further embodiment of the invention is the INTERLOCKS ment piece connected to an outer sliding sleeve of is hand gripped and displaced.

This measure ensures a particularly simple design Thus, the aforementioned advantages of easy handling for releasing the clutch.

In a further embodiment of the invention the INTERLOCKS ment piece on the bayonet insert side facing Recess which in the end position of the bayonet insert, pushed onto one end portion of the bayonet insert is, and the deferred locking pieces locks turning the bayonet insert.

This measure has the advantage that a compact design Locking is possible even with thin tubular shaft instruments will provide adequate rotation, that is, So can absorb high torques.

In a further embodiment of the invention the INTERLOCKS ment piece such, the bayonet insert facing end area to that of the inserted into the bayonet sleeve bayonet insert the locking piece pushes back initially and up rotatable relative to the end position to the locking piece is.

This feature has the advantage that the control or the Displacing the locking piece of the bayonet insert itself is performed without requiring further structural components are necessary. The bayonet insert pushes the latching piece, after it has taken on its end face, back and can be rotated relative to the locking member until the locking member is axially pushed onto the bayonet insert is what in the configuration with the spring-loaded INTERLOCKS ment piece then takes place automatically. This means that the hand habungsperson need to lock any other movements perform as for effecting the bayonet coupling, So pushing and twisting, it will automatically locked at the end of rotation of the bayonet insert. To the Solve needs accordingly only the locking piece, in the configuration with the outer sliding sleeve, by hand be moved to disengage the clutch again.

In a further embodiment of the invention the INTERLOCKS ment piece a centrally through to bore.

This measure has the advantage that the locking piece through devices such as a rod-shaped actuator can pass rich element, so that then the bayonet coupling at any particular axial location of a tubular shaft arranged, instrument with such actuator can be.

For this purpose, then are all the components with a through bore or opening.

The invention is further based on a selected described and illustrated exemplary embodiment. Show it

<b>Fig.</b> 1 in an exploded view the essential Components of a bayonet coupling according to the invention, and

<b>Fig.</b> 2 shows a longitudinal section of the two components in montier system, but not yet coupling state.

A bayonet shown in the figures coupling <b>10</b> has a bayonet sleeve <b>12</b> on.

In the bayonet sleeve <b>12</b> is a bayonet guide <b>14</b> provided the diametrically opposite each one of a withdrawable end <b>15</b> outgoing longitudinal slot <b>16</b> comprises of at the rear closed end in a transverse slot <b>18</b> passes, as is usual in bayonet guides.

The bayonet sleeve <b>12</b> is in a pod <b>20</b> recorded and rotatably connected with this (see illustration of <b>Fig.</b> 2).

The sleeve <b>20</b> continues in a slightly smaller diameter pipe section <b>22</b> continuing, diametrically on the outer side opposite lying two longitudinal slots <b>24</b> are provided.

On the lower-diameter pipe section <b>22</b> , a sliding sleeve <b>26</b> be pushed whose clear internal diameter is about the outer diameter of the pipe section <b>22</b> equivalent. In the sliding sleeve <b>26</b> are diametrically opposed holes <b>27</b> or. <b>27</b>'Is provided with the longitudinal slots <b>24</b> aligned. At the inside the sleeve <b>20</b> is also a hollow cylindrical locking piece <b>28</b> was added, which likewise diametrically opposite threaded holes <b>30</b> which cooperate with the longitudinal slots <b>24</b> the tube piece <b>22</b> or with the holes <b>27</b>. <b>27</b>'Of the sliding sleeve <b>26</b> aligned.

When assembled, see <b>Fig.</b> 2, the locking piece <b>28</b> in the piece of pipe <b>22</b> inserted and on the outside of the sliding sleeve <b>26</b> pushed, whereby this takes place, that the bores <b>30</b> the locking piece with the longitudinal slots <b>24</b> or the holes <b>27</b>. <b>27</b>'In the sliding sleeve <b>26</b> aligned. By inserting screws <b>32</b> or. <b>33</b> the sliding sleeve <b>26</b> fixedly connected to the locking piece <b>28</b> connected.

The assembly of the sliding sleeve <b>26</b> and locking piece <b>28</b> but is axially, corresponding to the length of the longitudinal slots <b>24</b>. slide back and forth, such as by the double arrow <b>47</b> is indicated.

As shown in the sectional view of <b>Fig.</b> refer 2, in the interior of the tube piece <b>22</b> a blind-hole-like abutment <b>34</b> provided, which a corresponding abutment <b>36</b> in INTERLOCKS ment piece <b>28</b> opposes.

This abutment <b>34</b> and <b>36</b> serve as support points for a coil spring <b>38</b>, In the assembled state (<b>Fig.</b> 2) to pressure is biased.

Due to the pressure force of the spring <b>38</b> thus the assembly from sliding sleeve <b>26</b> and locking piece <b>28</b> in the direction Insertion end of the bayonet sleeve <b>12</b> pressed.

At the end of the insertion of the bayonet sleeve <b>12</b> end facing , the locking piece <b>28</b> a recess <b>40</b> on. The recess <b>40</b> corresponds to a radial central incision, so that both sides of the recess <b>40</b> axially extending ago cracks <b>41</b> available.

The region of the recess <b>40</b> or the flanking projections <b>41</b> is in the range of the transverse slot <b>18</b> the bayonet guide <b>14</b>Such as in particular from the sectional representation from <b>Fig.</b> 2 is visible.

The locking piece <b>28</b> has this, the insertion end the bayonet sleeve <b>12</b> end facing a flat smooth forehead page <b>44</b> on.

The aforementioned assembly is at the distal end of a shank <b>46</b> a tubular shaft instrument provided, for example a medical forceps.

The bayonet coupling <b>10</b> further includes a bayonet use <b>52</b> on.

The bayonet use <b>52</b> has a hollow cylindrical portion <b>54</b> on, in its end section <b>55</b> radially across the hohlzylin drical portion projecting pins <b>56</b> and <b>57</b> are provided.

The contour of the pin <b>56</b> and <b>57</b> is chosen so that this in the bayonet guide can be inserted appropriately. To the the pin <b>56</b> and <b>57</b> opposite end of hohlzy -cylindrical section <b>54</b> with a shoulder <b>59</b> provided that a stop <b>61</b> forms.

The hollow cylindrical portion <b>54</b> extends in a mounting boss <b>63</b> continue. On the installation approach is a distal Working element mounted in the aforementioned example of a medical forceps are the corresponding chuck jaws.

From the sectional view of <b>Fig.</b> 2 it can be seen that both Components of the bayonet coupling <b>10</b> a central through exhibit opening through which, for example, a rod-shaped Actuate transmission element for operating the on the mounting boss <b>63</b> montier ten pliers jaw parts can be pushed.

To close the bayonet coupling <b>10</b> is the bayonet insert <b>52</b> compared to the presentation of <b>Fig.</b> 1 and 2 rotated through 90 °, and so on the bayonet sleeve <b>12</b> recognized that the pins <b>56</b> and <b>57</b> in the diametrically opposite longitudinal slots <b>16</b> the bayonet guide <b>14</b> can intervene. The bayonet use<b>52</b> is pushed forward until its front page to the front <b>44</b> the locking piece <b>28</b> applies. Another one Insertion shifts the locking piece <b>28</b> against the force the feather <b>38</b> so far that the pin <b>56</b> or. <b>57</b> before the cross slot <b>18</b> come. Henceforth, the inserted bayonet use<b>52</b> be rotated (see arrow <b>64</b>), Wherein the pin <b>56</b> and <b>57</b> in the transverse slots <b>18</b> enter. Has the bayonet insert<b>52</b> reaches its final rotational position that is in the <b>Fig.</b> 1 and 2 rotary position shown, the pins come <b>56</b> and <b>57</b> directly in front of the recess <b>40</b> in the end face <b>44</b> the INTERLOCKS ment piece <b>28</b> to lie.

The spring <b>38</b> now pushes the locking piece <b>28</b> about the spigot <b>56</b> or. <b>57</b>, Which then in the recess <b>40</b> occur, which is then shaped accordingly, ie that the spigot <b>56</b> and <b>57</b> can appropriately enter.

In this locking engagement between the locking piece <b>28</b> and bayonet use <b>52</b> is a turning of the bayonet insert <b>52</b> in the bayonet sleeve <b>12</b> blocked. The force of the compression spring<b>38</b> is set so as to at the usual manipulations the sliding sleeve <b>26</b> acting axial forces not to suffice the sliding sleeve <b>26</b> axially move.

To release the bayonet coupling <b>10</b> need only the sliding sleeve <b>26</b> against the force of spring <b>38</b> be moved, said locking piece <b>28</b> of the stud <b>56</b> and <b>57</b> the bayonet insert <b>52</b> be withdrawn, so that these are then twisted can.

After a slight twisting of the bayonet insert <b>52</b> , the sliding sleeve <b>26</b> be released. Are the pegs <b>56</b> and <b>57</b> at the height of the longitudinal slots <b>16</b> twisted been supports the spring <b>38</b> an expulsion of the bayonet insert <b>52</b> of the bayonet sleeve <b>12</b>,