Intra-oral evacuator system

[57] ABSTRACT

A dental oral evacuating system which includes a receptacle unit through which liquid and solid waste material passes after withdrawal from the oral cavity and means to connect the receptable to a source of flushing liquid for said receptacle. The system is connectable to a source of vacuum to effect such withdrawal of waste and a pressure-actuated switch in series with an electro-magnetically actuated valve, which controls the flow of flushing liquid to the receptacle, shutting off such flow unless the negative pressure in the receptacle is greater than a predetermined minimum amount to insure the delivery of flushing water only when suction is available to withdraw it from said receptacle.

Claims, 5 Drawing Figures

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PATENTED JUL Π 073

3.746,033

SHEET 1 OF 2

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PATENTED^! 7Ι97Λ 3,746,033

SHEET 2 Of 2

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FIG.

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INTkA-ORAL EVACUATOR SYSTEM

BACKGROUND OF THE INVENTION

With the advent of high speed dentistry during the past decade or more, the use of water by dentists for discharge into the oral cavity while performing various types of dental operations has greatly increased. This has necessitated the use of evacuating units of greater capacity than conventional saliva ejectors. Accordingly, so-called high volume evacuators, which are now employed for the removal of such excess water, as well as mouth fluids, during dental operations, include a tubular member having a diameter of approximately onefourth inch, which normally is held in the oral cavity by a dental assistant to free the hands of a dentist to operate dental instruments, support a dental mirror and the like.

One type of high volume capacity dental unit currently in use comprises the subject matter of U.S. Pat. No. 3,482,313, issued Dec. 9, 1969, in the name of George H. Stram. One of the advantages afforded by the type of evacuation system covered by said patent is the provision of flushing water which is discharged into a receptacle provided for purposes of accumulating solid waste material above a predetermined size. Such flushing water primarily is used to dissolve soluble matter and also to entrain fine sizes of solid material and discharge the same to a suitable sewer connection.

For purposes of providing adequate suction within the system covered by said patent, a pump of the type which develops a liquid seal is used. A pump of this type is fully adequate to handle substantial volumes of fluid in which waste material is entrained in view of the fact that the impeller of the pump is of the type adapted to directly engage the fluid material incident to passing it through the pump to suitable discharge ports.

There are vacuum pumps widely used at present, however, in oral evacuating systems which merely are capable of drawing air through the impeller of the pump member. In order to adapt this type of pump to an oral evacuator system, it is necessary to employ a separator unit capable of separating the suction air from the fluid waste material that is mixed therewith during passing of the same through the evacuator system and under which circumstances all of the fluid introduced into the system passes through the tube which is held in the oral cavity during the aforementioned dental operations. Under such circumstances, in the oral evacuating systems employing such air-type vacuum pumps, no additional flushing fluid is utilized, especially for purposes of enhancing the dissolving of waste material within a solids collector unit,.for example, or otherwise attempting to maintain the solids collector unit as clean and sanitary as possible.

In the event an attempt were made to introduce supplemental or auxiliary flushing water into a solids collector of an oral evacuating system in which the suction is generated by an air-type vacuum pump, there is a possibility that at least under some circumstances, the volume of flushing fluid may be greater than is capable of being handled by the solids collector and separator unit and some of the fluid may, under such circumstances, be discharged into the air-type vacuum pump and cause damage thereof.

Various developments have been made heretofore for purposes of preventing the excess flow of liquid into receptacles of various kinds in connection with dental evacuator units. Several of these have embodied the principle of providing spaced electrical electrodes at a predetermined level within a receptacle jar, for example, whereby the liquid may accumulate in such jar 5 until it rises into contact with said electrodes, whereupon a circuit is established therebetween which operates a switch in a manner to stop the electric motor by which suction-generating equipment is driven. In some forms of commercial devices, a floating switch opens 10 the motor circuit. Under such circumstances, the motor-stopping mechanism normally is intended primarily for safety purposes but when providing such an arrangement, and especially the electrodes in close association with a moist atmosphere or actual liquid vol¹³ umes, it is obvious that substantial electrical insulating means must be provided so as to minimize the possibility of shock to an operator or patient.

In the main, devices of the foregoing type also have been relatively complex and have not included flushing fluid for the purposes of facilitating the dissolving of soluble waste material and entraining relatively fine particles of solid material for discharge to sewer means. One such example of apparatus of this type is illus₂₅ trated in U.S. Pat. No. 2,784,717, dated Mar. 12, 1957.

Another type of apparatus having a similar purpose to that of said aforementioned patent is illustrated in re-issue U.S. Pat. No. 24,755, dated Dec. 15, 1959, and comprising a reissue of original U.S. Pat. No. 3θ 2,821,021, dated Jan. 28, 1958. In the latter re-issue patent, a float is caused to rise within the liquid at a predetermined level in order to energize a motor for an air-type suction pump when the liquid reaches such predetermined level. There also is no provision for 35 flushing fluid in said structure.

In view of the foregoing, the present invention has been devised to provide for the dental profession an intra-oral evacuator system which may be utilized with conventional vacuum pumps of either the air-type or 40 liquid seal type which are presently available in dental operatories and thereby eliminate the need for a dentist having to purchase a vacuum pump for purposes of obtaining the full advantages of the evacuator system which embodies the present invention, said advantages 45 and the characteristics thereof being as follows:

SUMMARY OF THE INVENTION

It is the principal object of the present invention to provide an intra-oral evacuator system adapted to be 50 connected to a conventional vacuum pump of either the air type or liquid seal type and include a solids collector to which a desired amount of flushing water may be delivered constantly during the operation thereof but insure the operation so that no excessive amount of ⁵⁵ flushing water is discharged into the solids collector at any one time, and thereby prevent filling of the system or causing possible damage to the vacuum pump, especially if the same is of the air-type.

It is another object of the invention to provide in the flushing water delivery system a valve which is operable by control means responsive to negative pressure within the solids collector whereby, unless there is adequate suction to withdraw waste liquid from the solids ₆₅ collector, the flow of flushing water thereto will either not occur or be discontinued in the event the vacuum range should fall below a predetermined value during operation of the system.

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It is a further object of the invention to provide in the flushing water conduit a solenoid-operated valve which is actuated by a vacuum-responsive switch connected in the electrical circuit to the solenoid from a source of electric current, the sensing element of said vacuumoperated switch being responsive to the interior of the solids collector and operable only when a predetermined value of vacuum exists in said collector.

It is still another object of the invention to provide an air-water separator unit between the fluid discharge conduit of the solid separator and the vacuum pump, such separator being utilized under circumstances where the vacuum pump is of the air-type, but such separator not being required when the vacuum pump is of liquid seal type or the equivalent thereof.

Details of the foregoing objects and of the invention, as well as other objects thereof, are set forth in the following specification and illustrated in the accompanying drawing comprising a part thereof.

DESCRIPTION OF THE DRAWING

FIG. 1 is a diagrammatic type illustration of an intraoral evacuator system embodying the principles of the present invention, certain of the elements shown therein being foreshortened for purposes of adapting the same to the figure.

FIG. 2 is a fragmentary side elevation of the solids collector unit of the system shown in FIG. 1, illustrated on a larger scale than employed in said figure and being partly broken away to illustrate details thereof, in stretch-out manner.

FIG. 3 is a top plan view of a portion of the system shown in FIG. 1.

FIG. 4 is a fragmentary vertical sectional view of the air-separator unit shown in FIG. 1.

FIG. 5 is an enlarged vertical sectional view of the vacuum-actuated switch shown in FIGS. 1-3 on a larger scale than employed in said figures.

DETAILED DESCRIPTION

Referring to FIG. 1, a somewhat diagrammatic layout of an exemplary intra-oral evacuator system is shown which embodies the principles of the invention for purposes of illustrating the details and characteristics thereof. In said system, a vacuum pump 10 is shown which is designated the air type to exemplify a suitable source of vacuum. The selection of an air type vacuum pump has been made because of extensive use of this type of pump in existing evacuator systems. However, the invention is equally applicable to any intra-oral evacuator systems in which a fluid type pump, such as a liquid seal pump or otherwise, comprises the source of vacuum. It also is to be understood in the following description and claims that vacuum also is referred to as a negative pressure.

The principal object of the invention, as indicated aobve, is to supply flushing water to a solids collecting receptacle 12 by automatically operable control means adapted to prevent excess accumulation of flushing water within the receptacle 12 and thereby eliminate flooding thereof and possible damage to the vacuum pump, especially in systems where the vacuum pump is of the air type. By way of example, one air type of vacuum pump is that which is employed in certain forms of vacuum cleaners adapted for household use, such as the so-called pot type, in which a canister has a com partment to contain waste material and an electrically operated blower fan is mounted in the canister.

In view of the fact that the present invention is concerned primarily with the solids collecting receptable 5 12, attention is directed to FIG. 2 in which details thereof are illustrated on a larger scale than in FIG. 1 and the container 14 of the receptacle 12 is extensively broken away to disclose interior detail. For convenience, it will be seen that the container 14 of recepta10 cle 12 may be a suitable size of jar which may be formed from glass, transparent synthetic resin, or otherwise in order that, preferably, the contents of the container may be observed visually, for convenience rather than necessity.

To facilitate emptying accumulated solid material from the container 14, the same is readily detachable from a cap or vacuum manifold 16 which is threadably connected to the upper end of the container 14 and may be suitably formed from metal, synthetic resin, or the like by appropriate molding or casting. If desired, a convenient gasket 18 may be mounted in conventional manner between container 14 and vacuum manifold 16. Also, especially as shown in FIGS. 1 and 2, it will be seen that the receptacle 12 preferably is mounted, in use, in vertical position with the container 14 thereof lowermost.

With further reference to FIG. 2, and also with incidental reference to FIG. 3, it will be seen that the vacuum manifold 16 is provided with a plurality of ports ³θ within which portions of certain conduits are mounted so as to project therefrom. Included among such conduits are conduit 20 which projects a substantial distance below the lower surface of vacuum manifold 16; conduit 22, which preferably projects upwardly from ³⁵ vacuum maniford 16; conduit 24, which is connectable to a source of water; and conduit 26 to which a pressure-actuated unit 28 is connected. Specifically and preferably, the unit 28 is a vacuum-responsive electric switch, details of which are shown in FIG. 5. An adjust⁴⁰ able, vacuum-limiting valve 30, which preferably is of a conventional, commercial type, communicates with the interior of receptacle 12 through elbow 31 to prevent a negative pressure, in excess of a predetermined amount, from being developed. Any negative pressure ⁴⁵ in excess of such predetermined amount, if applied to the receptacle 12, results in opening the valve 30 to permit the introduction of ambient atmosphere.

It has been indicated above that the lower end 32 of conduit 20 extends a predetermined distance below ^υ vacuum manifold 16. As shown in FIG. 2, it will be seen that the lower end 32 of the conduit is located an adequate distance above the bottom of container 14 to permit the accumulation of a reasonable amount of waste fluid within receptacle 12. When the fluid rises above the lower end 32 of conduit 20, however, suction applied to conduit 20 by a vacuum pump 10, through intermediate units and conduits, will result in withdrawal of waste fluid from the interior of receptacle 12. ₆₀ To control the size of solid particles which may be entrained within the waste fluid and withdrawn from receptacle 12, a filter 34 with a diameter larger than conduit 20 surrounds the portion of said conduit which projects into the receptacle 12. The porosity of filter 34 is selected to permit passage of solid particles of a predetermined maximum size. In actual construction, the filter 34 may be formed from screen cloth of desired mesh size, which preferably is formed from non

3,746,033 corrosive material. For convenience, the upper end of filter 34 may surround a short supporting tube 36 which is press-fitted or otherwise received within a suitable socket formed in vacuum manifold 16, as clearly shown in FIG. 2.

The outer end of conduit 20 is connected to additional conduit 38 which, at its outer end, is connected to an inlet tube 40 of an air-water separator unit 42. Details of the latter are shown in FIG. 4 and it will be seen that the lower end of inlet tube 40 extends a substantial distance downwardly from the cap 44 into the cup-shaped receptacle 46. The receptacle 46 has an air discharge conduit 48 projecting upwardly through the bottom thereof to within a short distance of the cap 44, the upper end of conduit 48 being open at all times for the withdrawal or air therethrough by the vacuum pump 10. From FIG. 1, it will be seen that the conduit 48 extends between the separator unit 42 and the air inlet of the vacuum pump 10. Also, connected to the bottom of receptacle 46 is a waste fluid conduit 50 which, as seen in FIG. 1, extends downwardly and outwardly to a suitable sewer connection, not shown. A water seal gooseneck 52 may be provided in the conduit 50, if desired.

Conduit 22, which extends upwardly from vacuum manifold 16, is provided for purposes of connecting, for example a high volume evacuator conduit 54 thereto. It will be understood that the conduit 54 is formed from flexible, durable material and is of adequate length to enable, for example, a high volume evacuator handpiece 56 to be connected to the outer end thereof by suitable means. The handpiece 56 has an appropriate nozzle member 58 connected to the outer end thereof for use by a dental assistant, for example, by inserting the same in the oral cavity of a patient while the dentist is performing dental operations within the cavity that require the withdrawal of relatively high volumes of waste fluid. Examples of waste fluid are flushing and/or cooling water, which is discharged into the oral cavity, especially during such operations as cutting or drilling with a high speed dental handpiece, grinding, or polishing, as well as while undertaking certain prophylaxis operations in which flushing fluid is utilized. The foregoing examples are given only by way of illustration and are not to be regarded as being restrictive.

At the time such aforementioned high volume evacuator means is being utilized, the vacuum pump 10 will be operating, and waste fluid, as well as any solid particles which are entrained therein will be withdrawn from the oral cavity through nozzle 58, conduit 54, and discharged through conduit 22 into the interior of container 14. When the level of the fluid is above the lower end 32 of conduit 20, the fluid and any entrained solid particles which are capable of passing through the openings in filter 34 will be drawn through the additional conduit 38 into the separator unit 42 for the removal of fluid from the air in order that the fluid may discharge to the sewer connection, while the air passes through conduit 48 into the vacuum pump 10. As indicated above, the air-water separator unit 42 preferably is utilized only when the vacuum pump 10 is of the air type. If it is a fluid type pump, such as a liquid seal pump, the separator unit 42 may be dispensed with and all of the fluid will be passed through the pump unit to the sewer connection.

Water conduit 24 is connected by means of an inlet conduit 60 to a source of water under pressure, such as is available from a domestic or commercial water supply system. To control the flow of the water therethrough, a control valve 62 is mounted in the line 60. Preferably, the valve 62 is operated by an electric solenoid 64, operation of which is controlled by the pressure-actuated unit 28, details of which are as follows:

From FIG. 2, it will be seen that conduit 26 extends upwardly from the vacuum manifold 16 in a position which does not conflict with the various conduits leading upwardly and laterally from the vacuum manifold 16. To effect communication with the interior of receptacle 12, conduit 26 extends through vacuum manifold 16. Also, if desired, additional conduits and connecting nipples 66 and 67 may be provided to connect a cuspidor and hydrocolloid unit to the manifold head 16.

Referring to FIG. 1, electric conduits 68 and 70 are connected at one end to power line conduits, not shown. The opposite end of conduit 68 is connected to one contact of pressure-actuated unit 28, which, as indicated above, preferably is a vacuum switch. Conduit 71 is connected to the conventional connecting contacts of electrical solenoid 64 and then is connected to the other connector of vacuum switch 28, details of which are as follows:

Referring to FIG. 5, pressure-actuated unit 28 is vacuum responsive by means of a flexible diaphram 72, the periphery of which is clamped between a mounting disc 74 and a clamping disc 76. Clamping disc 76 has a central aperture which receives the upper end of a switch actuator 78 which is formed from insulating material and is operated axially by diaphram 72. A contact screw 80 has a supporting end of a flexible switch contact leaf 82 connected fixedly thereto, the leaf 82 supporting a movable electric contact 84 on the outer end thereof. Said contact 84 is adapted to make and break a circuit with adjustable fixed contact 86 carried by the inner end of a second adjustable contact screw 88. Diaphram 72 and actuator 78 are arranged normally to hold contact 84 out of engagement with fixed contact 86.

The vacuum switch 28 also is provided with a mounting stem 90 which is provided with a central inlet port 92 extending longitudinally thereof for communication with the space between mounting disc 74 and diaphram 72, whereby the diaphram is rendered responsive to the pressure, and particularly negative pressure, which is transmitted through the inlet port 92 in mounting stem 90. When negative pressure of a predetermined value is developed in the system, diaphram 72 is flexed downwardly, as viewed in FIG. 5, and the resilience of leaf 82 moves actuator 78 downwardly and carries contact 84 into engagement with fixed contact 86 to energize solenoid 64 and close valve 62 in waterline 60. The mounting stem 90 preferably is threaded and is connected to an appropriate female fitting provided on conduit 26, as shown in FIGS. 1 and 2.

In view of the fact that flushing water which is supplied through inlet conduit 60 to the interior of container 14 of receptacle 12 is under conventional municipal water pressure, it is essential that appropriate control of the flow thereof into container 14 must be exercised to prevent the container from flooding and especially to prevent damage to the vacuum pump 10 under circumstances where the same is of the air type. The control mechanism described above and illustrated es3,746,033 pecially in FIGS. 1 and 2 is highly suitable to effect the desired control both safely and automatically.

It will be understood that when the oral evacuating handpiece 56 is being utilized, the vacuum pump 10 is operating in order to produce continuous negative pressure or vacuum within the interior of container 14, within the desired range. The capacity of the pump 10 is selected to be adequate to withdraw at an appropriate rate, from the interior of container 14 reasonable operable amounts of waste fluid and entrained solid material therein, as well as flushing fluid, which is discharged through conduit 24 into container 14 at a desired rate which is controlled by the capacity of valve 62. Therefore, the negative pressure developed within container 14 during operation of the evacuating handpiece is highly suitable as a means for actuating solenoid 64 of valve 62 through the response of vacuum switch 28 to the degree of vacuum existing within the container 14 at any given period.

The supply of flushing fluid to the container 14 is desirable, particularly when using a liquid seal pump as the source of vacuum in order that an adequate supply of fluid at all times will be available to effect such seal. However, under circumstances when an air type vacuum pump 10 is utilized, supplying flushing fluid to the container 14 also is desirable to insure adequate dissolving of soluble waste material and thereby maintain the filter 34 in as clean condition as possible to enhance the maximum passage of fluid therethrough, whereby the system is maintained in a reasonably sanitary condition. This results, normally, in the only material which is accumulated within the container 14 comprises solid material which is of a size too large to pass through the openings in the filter 34.

While the invention has been described and illustrated in its several preferred embodiments, it should be understood that the invention is not to be limited to the precise details herein illustrated and described since the same may be carried out in other ways falling within the scope of the invention as illustrated and described.