DE60125488T2 - Flexible switching element for hand-operated switches - Google Patents

Description

BACKGROUND THE INVENTION

These Application relates to ultrasonic surgical systems and more precisely switching elements with membrane seals, which prevent gas and Water vapor come into contact with switching arrangements, which in one inner switching chamber are arranged, which formed in a surgical handpiece is.

It is known that electrical Scalpels and lasers are used as surgical instruments can, for the double function of simultaneous incision and hemostasis soft tissue by cauterizing tissues and blood vessels. however Such instruments work at very high temperatures to coagulate reaching what causes evaporation and vapors as well as spraying. In addition, the leads Use of such instruments often to relatively wide zones of thermal damage of tissue.

The Cutting and cauterizing tissue using surgical instruments, e.g. Sounds at high speeds through ultrasonic drive mechanisms are vibrated, is also known. In such systems an ultrasonic generator is provided which is an electrical Signal of a certain voltage, current and frequency, e.g. 55,500 cycles per second, generated. The generator is over Cable with a handpiece connected, which contains piezoceramic elements containing an ultrasonic transducer form. In response to a switch on the handpiece or a footswitch that connected to the generator by another cable, that will Generator signal applied to the transducer, causing a longitudinal vibration of its elements. A structure connects the transducer with a surgical blade, therefore, with ultrasonic frequencies is vibrated when the generator signal is applied to the transducer becomes. The structure is designed to be at the selected frequency resonates, thus amplifying the motion of the transducer has been initiated.

Around the handpiece to activate, so that the blade is put into swinging or otherwise operated, becomes one Switching mechanism operated by the user. The switching mechanism comprises typically one or more switch button elements which the User depresses, to activate the blade. Since it is necessary that the handpiece after The service must be cleaned and / or maintained, the internal electronic Components of the switching mechanism to the environment outside the handpiece sealed be around while cleaning, use, handling or maintenance damage to the prevent electronic components. This is especially true for handpieces that autoclavable and / or submergible. Consequently, a membrane (e.g., a flexible seal) as a part of the switching element to Sealing the electronic components of the switching mechanism included be so that that handpiece can be cleaned and / or maintained without the electronic components damaged.

typically, is the switching element (which has button areas) of a yielding Material, such as an elastomeric material, formed to provide a sealing effect to provide between the switching element and the handpiece. Elastomeric knobs are In general, no good barriers against the ingress of moisture (Water vapor), especially moisture ingress due to a Autoclaving operation. Elastomeric materials are against piercing sensitive by sharp instruments. If during the autoclaving operation Moisture passes through these elastomeric barriers has the Moisture afterwards no quick way to stop the autoclaving operation to escape from the handpiece. The Presence of moisture in an internal cavity of the handpiece, in the electronic components are housed, damage and / or Malfunction of the handpiece cause premature wear or tear.

If the switching element in the form of an elastomeric switching element present, can be a one-piece flexible membrane provided around its outer area be. This flexible membrane is often referred to as a "skirt" or "skirt" which it allows the Switch body easily depressed becomes, when pressed, and in its original one Position returns when is released. There are at least two disadvantages with the Use a thin one elastomeric apron as a part of the body a rocker switch element are connected. First, the piercing / tear resistance of the apron area, there the apron area a relatively thin one Cross-section has and limited Durability has to withstand piercing of sharp instruments which touch the bending area (the apron). Second, the Thinness of apron membrane not a very robust seal, because air and moisture pass through it can. In other words, the apron membrane has a sufficiently high permeability that allows air and Moisture through them.

An example of the difficulty encountered in a high permeability switching element when the switching element is subjected to an autoclaving process. When the rocker switch element is used to seal an internal cavity of the handpiece, an autoclaving vacuum can cause the air pressure inside the internal cavity to be higher than outside the internal cavity. The switching element has a limited movement path in an outward direction and thus can not encounter the higher pressure. As a consequence, pressurized air escapes through the skirt membrane due to its relatively poor permeability. It is also possible that the pressurized air can escape through other parts of the switching element body. However, during repressurization in the autoclave to normal atmosphere, the reduced pressure within the internal cavity causes the switching element to deflect downwardly. This causes the switching element to be pulled down, similar to someone pressing on the switching element. Thus, the switching element balances the pressure and there is insufficient pressure differential to draw air back through the skirt membrane. This results in that the switching element is held down without intervention of a user. This is undesirable because it results in undesirable activation of the switching mechanism because the switching element is in a depressed position.

Even though existing membrane for Some applications have been suitable, there is a need for Provide improved membranes that are good barriers to the Moisture, along with being one good barrier against the passage of Gas vapor and other gas (air) together with improved resistance form against puncture.

Exemplary switching elements of the prior art are in US 5,226,904 and in the US 4,373,124 described. The US 5,226,904 forms the basis for the introductory part of claim 1, as attached hereto.

SUMMARY THE INVENTION

The The present invention is directed to switching elements as in claim 1 defining the fluid flow (e.g., the flow of Controlling water vapor and gases, such as air) through the switching elements, which are used to create an internal cavity of a surgical handpiece seal and in each case a depressible element for actuating the handpiece form. The switching elements provide improved sealing properties, which the passage of Fluids over the whole switching element or at least one treated area its (e.g., skirt) into and out of the sealed interior Prevent switch chamber. The switching elements are also resistant to the puncture, that on the impact of tools and cleaning instruments and the like is due.

The Switching elements find particular use in handpieces that are autoclavable. Autoclave pressures and vacuums can gas flow and cause water vapor flow through the membranes of conventional switching elements and in particular by their thin ones Edge groin. The present application discloses various A method of controlling the gas and water vapor flow through the depressible switching element (Especially the edge strip area), such that the handpiece in a Autoclave environment and used in another unfavorable environment can be without the Disadvantages are experienced, which are associated with conventional elements are.

Further Features and benefits will become apparent from the following detailed description clearly, if in conjunction with the attached drawings is read.

SHORT DESCRIPTION THE DRAWINGS

The The above and other features will become more readily apparent from the following detailed description and drawings of illustrative embodiments clearly, wherein:

1 Figure 3 is an illustration of a console for an ultrasonic surgical cutting and hemostasis system as well as a handpiece and footswitch according to an exemplary embodiment;

2 Fig. 10 is a cross-sectional view showing an exemplary switch end cap;

3 a top perspective view of an exemplary switching element for use with the switch end cap of 2 is;

4 a perspective view of the switching element of 3 from below is;

5 Figure 3 is a bottom perspective view of a switching element according to an exemplary embodiment;

5A a broken cross-sectional view along the line AA of 5 is;

6 FIG. 4 is a broken cross-sectional view of a switching element according to another exemplary embodiment, wherein a substrate is provided between the switching element and a permeability barrier; FIG.

7 a perspective top view of a switching element according to another exemplary embodiment;

8th a perspective view of a switching element according to another exemplary embodiment from below;

8A a side view of a switching element according to another embodiment;

9 a perspective view of a switching element according to another exemplary embodiment from below;

9A a broken cross-sectional view along the line AA of 9 is;

10 is a partially broken cross-sectional view of a Schalterendkappe in which a ventilation is formed;

11 Fig. 12 is a cross-sectional view of a resistive switching arrangement according to another embodiment;

12 an exploded view of a switch end cap according to another exemplary embodiment;

13 a cross-sectional view of the switch end cap the 12 is in a built-in state;

14 is a side elevational view of a bellows switch, the switch end cap at 12 is used;

15 a cross-sectional view taken along the line 15-15 of 14 is;

16 an exploded view of a switch end cap according to another exemplary embodiment.

DESCRIPTION ILLUSTRATIVE EXEMPLARY EMBODIMENTS

With reference first to 1 FIG. 3 illustrates and is generally illustrated with an exemplary surgical cutting and hemostasis system according to one embodiment 10 designated. In the exemplary embodiment, the system is 10 an ultrasound surgical system. The system 10 includes a console or a housing 20 which includes an ultrasonic generator (not shown) and a control system located within the console 20 which is part of the system 10 forms. A first cable 22 connects the console 20 with a handpiece 30 and serves to provide an electrical connection between them. The first cable 22 comprises a first set of wires (not shown) which allows electrical energy, ie drive current, to be dissipated from the console 20 to the handpiece 30 where she is sent to a surgical instrument 11 applying an ultrasonic longitudinal movement. The surgical instrument 11 is preferably a scalpel blade or a shearer. This instrument 11 can be used for simultaneous cutting and cauterization of tissue.

The supply of ultrasonic current to the handpiece 30 is through a switch mechanism 40 controlled within the handpiece 30 is arranged. As will be described in further details hereinafter, the switch mechanism 40 electrically with the console 20 More specifically, with its generator, through one or more wires (not shown) of the first cable 22 connected. The generator can also be optional and continues through a footswitch 50 be controlled by a second cable 60 with the console 20 connected is. Thus, in use, a surgeon may apply an electrical ultrasonic signal to the handpiece 30 create what causes the instrument 11 oscillates at an ultrasonic frequency in the longitudinal direction by the switch mechanism 40 of the handpiece 30 or the footswitch 50 be operated. The switch mechanism 40 is activated by the surgeon's hand, and the footswitch 50 is activated by the surgeon's foot.

The console 20 also includes a liquid crystal display device 24 which may be used to indicate the selected cutting force level in various ways, such as the percentage of maximum cutting power or numerical power levels associated with the cutting performance. The liquid crystal display device 24 can also be used to display other parameters of the system. A circuit breaker 26 and a performance "to" indication 28 are also on the console 20 provided to allow the user to operate the system 10 continue to control. Additional buttons and control switches, in general with 70 designates various other functions of the system 10 and can be on the front panel of the console 20 are located. When the energy by pressing either the switch mechanism 40 or the switch 50 to the ultrasonic handpiece 30 is applied, causes the surgical scalpel or instrument 11 oscillates with the amount of longitudinal motion that varies in proportion to the magnitude of the applied drive power (current) as it is adjustably selected by the user.

Well with respect to the 1 to 4 is an exemplary switch mechanism 40 in further Details in 2 shown. The hand piece 10 is from a switch end cap 90 formed on a handpiece body 92 is attached. The switch mechanism 40 includes several electrical components, eg one or more circuit cards 80 , And also includes one or more niederdnückbare switch elements 82 which are operated by the user to activate or deactivate the switch mechanism. Merely for purposes of illustration, the switching element 82 shown in the form of a switch of the rocker type; however, it will be understood that the switching element 82 any number of depressible switching elements 82 and is not limited to a switch of the rocker type. The exemplary switching element 82 includes a body 83 (in this case a body of the type of rocker) and a sidebar 85 , which are in the border area around the body 83 extends. The switching element 82 serves to an interior of the handpiece 10 seal and thus functions as a water vapor and gas barrier (ie, a permeability barrier for liquids and gases). Preferably, both the body act 83 as well as the sidebar 85 as permeability barriers. The switching element 82 Also includes a pair of spaced pins 87 that are different from the body 83 for engagement with a contact (not shown) extend outwardly to activate the switch mechanism 40 ( 1 ) to effect. The cones 87 , in an uncompressed state, preferably do not extend below a plane which defines the lower surface of the skirt 85 contains. Because the cones 87 preferably formed from an elastomeric material, such as the body 83 as well as the sidebar 85 are, causes a force on the upper surface of the body 83 above the cones 87 is exercised that the respective pin 87 is driven down so that it extends beyond the plane, which is the lower surface of the skirt 85 contains. This is the compressed position of the switching element 82 ,

In the illustrated embodiment, the switch end cap includes 90 two opposite switching elements 82 that with the switch end cap 90 are coupled. The switch end cap 90 has an outer shell 94 , which are the electrical switching components, as well as the circuit boards 80 , houses. Because every switching element 82 in communication with the switch mechanism 40 is, there are openings in the outer shell 94 formed it to the switching element 82 to allow at the switch mechanism 40 attack so that signals from the switch mechanism 40 generated and to the console 20 delivered to the operation of the handpiece 10 to enable.

The hand piece 10 is preferably intended for use in a surgical system, such as that disclosed in European Patent Application No. EP-A-1 199 047 (Attorney Docket P028404EP) (which claims priority from USSN 09 / 693,621) , which is also hereby registered. And the handpiece 10 is described in further detail in European Patent Application No. EP-A-1 199 040 (Attorney Docket P028413EP) (which claims the priority of USSN 09 / 693,549).

In one aspect, an improved switching element 82 disclosed in the form of an elastomeric switch button type a rocker. It will be understood that although the term "elastomeric" is used herein, the switching element 82 can be formed from other suitable plastics, such as a thermoplastic. Additionally, although the discussion will focus on switching elements used in switch mechanisms, it will be appreciated that other types of plastic components, such as gaskets, walls or other components, may be replaced by the switch membranes. Furthermore, although exemplary shift elements are discussed herein as being rocker type, it will be understood that the scope of the present application covers other types of shift elements. Accordingly, the description and illustration of rocker type switching elements is merely illustrative and not restrictive.

With reference to the 3 - 5A In one exemplary embodiment, a metallic layer is used 110 on the elastomeric switching element 82 Applied to the type of rocker, as in 5 shown. The edge strip is preferred 85 integral with the body 83 educated. More precisely, the metallic layer 110 on a bottom 112 the elastomeric rocker switch element 82 applied. The layer 110 may be formed from any number of suitable metallic materials, eg aluminum, gold, titanium, platinum. The layer 110 is in the form of a thin layer of metal on predetermined portions of the underside 112 of the body 83 and the sidebar 85 is applied. For example, the entire bottom 112 (including the body 83 and the sidebar 85 ) with the metallic layer 110 which is a thin coating (eg, the thickness may be from about 0.127 μm (5 μ inches) to about 12.7 μm (0.0005 μ inches).) As an alternative, the metallic layer 110 only on the sidebar 85 of the switching element 82 arranged. The metallic layer 110 dramatically reduces the water vapor and gas transmission rates of the treated part, e.g. B. the bottom 112 , Because the layer 110 is very thin, is the layer 110 flexible and does not affect the flexibility of the elastomeric part (the switching element 82 ). The presence of the metallic layer 110 thus improves the density i properties of the switching element 82 , The metallic layer 110 is not limited to that only on the bottom 112 is applied, but rather the metallic layer as an intermediate layer of the switching element 82 between the upper surface and the underside 112 be formed. The metallic layer 110 can only be in an intermediate layer of the sidebar 85 be formed. The metallic layer 110 can also be on the top surface of the item 82 alone or in combination with being on the bottom 112 or as an intermediate layer. The metallic layer 110 can be applied using conventional techniques including the use of a spray device or other type of device which serves to apply a thin metallic layer, preferably of uniform thickness, to a body. Other techniques that can be used to make the metallic layer 110 include, but are not limited to, ion beam deposition, metal vapor deposition, and chemical vapor deposition.

In a further embodiment, in 6 is a thin flexible substrate 120 provided and is with a metallic layer 122 coated. The substrate 120 is preferably formed from a flexible material such as polyurethane, vinyl, silicone, a thermoplastic elastomer, polyvinylidene fluoride, polyparaphenylene terephthalamide, polyimide, and a combination of any of the foregoing. For example, a polyimide film may be coated with an FEP fluoropolymer resin to provide a moisture barrier and a slippery surface which reduces the tendency of a tool to puncture the element. In an exemplary embodiment, the substrate has 120 a thickness of about 12.7 μm (0.0005 inches) to about 16.2 μm (0.003 inches). The metallic layer 122 may be formed from any number of suitable metals, including, but not limited to, aluminum, gold, titanium, and platinum. The metallic layer is preferred 122 formed of a metal which allows the metallic layer 122 thin, while at the same time the metallic layer 122 has low water vapor and Gasdurchlaßraten. The thickness of the metallic layer 122 In one embodiment, it is between about 0.127 μm (5 μ inches) and about 12.7 μm (0.0005 inches). The metallic layer 122 is on a first surface 124 thin flexible film substrate 120 educated. An opposite second surface 126 thin flexible film substrate 120 is attached to or points to the bottom 112 the elastomeric rocker switching element 82 if the hand piece 30 assembled. In one embodiment, the substrate becomes 120 to the bottom 112 of the switching element 82 glued using an adhesive. The thin flexible film substrate 120 can be on or immediately below the bottom 112 to be brought. For example, the thin flexible film substrate 120 in laminate contact with the elastomeric rocker switch element 82 be so that the metallic layer 122 away from the elastomeric rocker switch element 82 points as in 6 shown. The thin flexible film substrate 120 can also be in close proximity, but separated, from the elastomeric rocker switch element 82 to be ordered. It will be understood that the substrate 120 on selected parts of the bottom 112 can be brought up. For example, the substrate 120 just on the bottom of the sidebar 25 can be applied or applied to the entire bottom 112 be applied.

Any pressure differential problems beyond the element 82 can be experienced (such as during a cleaning process in an autoclave), can be reduced to insignificant levels by the volume of air in the sealed switching chamber below the element 82 is reduced. Filling the empty area under the element 32 reduces the amount of air under the element 82 , which is affected by heat and pressure, so that the differential pressure across the element 82 reduced and thus the adverse effects on the switching element 82 be reduced. This is particularly useful in applications such. As autoclaving processes, noted where a force on the element 82 acts. It will be understood that a small area under the element 82 needed to make it the pin 87 or the like to allow it to move when the element 82 depressed or when it returns to a non-compressed position.

The water vapor and gas transmission rates of the elastomeric switching element 82 can also be reduced by the elastomeric switching element 82 a cryogenic temperature environment is exposed to the molecular microcrystalline structure of the elastomeric switching element 82 to reorganize and / or denser to organize and / or refine. This leads to a decrease in porosity, water vapor and Gasdurchlaßraten and improves the gas-tightness of the elastomeric switching element 82 , A suitable technique is the elastomeric switching element 22 in a progressive thermally controlled liquid nitrogen environment. Another benefit of this treatment is the improved strength (roughness) and resistance to puncturing of the elastomeric switching element 82 This is particularly useful for the durability of thin elements that have been heavily bent or challenged by pointed instruments.

The flexibility and ability to relocate Can be improved by wrinkles or waves 220 in the puncture resistant edge strip 210 be incorporated as in 8A shown. Due to the superior resistance of the puncture resistant rim 210 against piercing, the bending area is much more resistant to piercing than an elastomeric skirt (skirt). These wrinkles / waves 220 provide a spring-like feedback effect, which the rocker 200 returns to its top position when the rocker 200 no longer being depressed. These wrinkles / waves 220 may also provide detent action and snap-in behavior providing tactile feedback to the user. Springs or domes (not shown) can under the rocker 200 used, if necessary, to the means for returning the rocker up when the rocker 200 be released, supplemented or provided for in Plastic springs / domes may be particularly useful in the presence of steam and heat because of their non-corrosive nature. Also has the resistant to puncture sidebar 210 an improved resistance to air flow, which thus the permeability of the rocker 200 reduced. This reduced permeability simplifies the correct behavior of the rocker during and after autoclaving.

Furthermore, the selection of the film discourages the puncture resistant rim 210 or an additional coating that has a smooth surface with little friction (compared to an elastomer that has a higher friction), the puncture / slitting during cleaning / handling. Suitable low friction materials include, but are not limited to, polyimides, polyesters, polytetrafluoroethylene materials, and titanium nitride. For example, instruments such as brushes that hit a slippery element will slip over the element rather than pierce it, as compared to a normal elastomeric element. Thus, the formation of the puncture resistant rim improves 210 such that at least one of its surfaces has a low friction surface, the resistance of the puncture resistant rim 210 against puncture. An additional surface treatment, such as ion implantation, can also be used.

Another method for improving the switching element 200 for better durability and improved resistance to air / moisture flow, it is to keep the skirt membrane intact, certain surfaces of the switching element 200 however, to treat on the surface using a suitable surface treatment process. More specifically, at least the skirt membrane surface (skirt) is surface treated, and preferably the surface treatment is done inside (bottom) and / or outside of the rocker switch element 200 , For example, the entire underside may be surface treated. Surface treatments that can be used include metallic coatings (such as aluminum, gold, titanium, platinum, etc.).

As previously mentioned, it may be that the thinness of the skirt (i.e. a flexible seal) does not form a very robust seal, since air and moisture can penetrate. In other words the permeability the sidebar in conventional Configurations high. Although it is desired that the sidebar a low permeability typically has some amount of permeability. The Amount of gas / moisture passage through the skirting and other parts of the element depends on the pressure difference every page of the element.

The switching element 82 ( 3 ) is designed to provide substantial displacement in an outward / upward direction and an inward / downward direction. This possibility of symmetrical displacement reduces the differential pressure across the element, thus reducing the gas / moisture flow through the element. By reducing the current through the element, the rocker is able to return to its normal position after autoclaving, unlike conventional rockers that tended to be held down without user intervention, as previously described. Another benefit of the reduced flow is the higher reliability because moisture does not migrate easily into the interior of the sealed chamber to potentially affect components.

According to the present invention, the symmetrical displacement can be accomplished by several means. An example is using wrinkles or waves 220 as in the switching element 200 of the 8A shown. Using wrinkles / waves 220 in the sidebar area 210 allows the movement upwards as well as the movement downwards. Another method is to provide sufficient looseness in the element, allowing the element to expand outward as well as inward. Furthermore, an elastic material, for. As polyurethane, which is slightly elongated, be used to form the rocker, thus allowing the rocker expands outward. In all of these embodiments, the differential pressure across the element is controlled by sufficient rocker movement in both directions.

It will now be referred to 11 taken in which a durable switching arrangement is shown and in general with 400 is designated. The switching arrangement 400 is slightly depressed at low pressure, but has a relatively thick outer shell 402 which is resistant to puncture and gas flow damage. For example, and in accordance with an exemplary embodiment, the thickness is the outer shell 402 from about 0.04 inches to about 0.06 inches. The outer shell 402 is in the form of a finger-depressible shell, which is bubble-dome shaped, and may be formed of various materials including, but not limited to, polyimides, polyesters, and other suitable materials. The outer shell 402 has two active areas, namely a first area 404 and a second area 406 , Due to the dome shape is the outer shell 402 easily deformed by finger pressure to activate the switch mechanism 410 to effect. The first area 404 has a first pen 408 that is different from the outer shell 402 on the switching mechanism 410 to extend. An end 407 of the first pen 408 is preferably integral with the outer shell 402 connected, and an opposite end 409 is close, but not in contact with the switching mechanism 410 in the in 11 arranged rest position shown. The second end 409 has a first contact surface 412 that on a first button 414 rests on a PCB 420 is formed, which is part of the switching mechanism 410 forms. The first button 414 is preferably axially with the first contact surface 412 aligned so that the depression of the first area 404 causes the first contact surface 412 the first button 414 touched, resulting in activation of the switching mechanism 410 leads.

Similarly, the second area has 406 a second pen 416 that is different from the outer shell 402 on the switching mechanism 410 to extend. An end 417 of the second pen 416 is preferably integral with the outer shell 402 connected, and an opposite end 419 is close to but not in contact with the switching mechanism 410 in the in 9 arranged rest position shown. The second end 419 has a second contact surface 422 that on a second button 424 rests on the PCB 420 is formed, which is part of the switching mechanism 410 forms. The second button 414 is preferred with the second contact surface 422 aligned, so that the depression of the second area 406 causes the second contact surface 420 the second button 424 touched, resulting in activation of the switching mechanism 410 leads.

As an option, a middle carrier pin 430 be provided to reduce the unintentional activation when the center of the outer shell 402 held or pressed. The middle carrier pin 430 extends from the outer shell 402 to the switching mechanism 410 , In the resting position of 11 the middle carrier pin rests 430 on or in close proximity to an inactive area of the switching mechanism 410 , Furthermore, both the first and the second area 404 . 406 have their own flexible membrane (not shown) to further reduce the pressure to activate by depressing. The exemplary outer shell 402 shows a graduated zone 440 located on both the first and second areas 404 . 406 is provided. The graduated zones 440 provide a finger touch point for the user to depress, so that the respective first and second pin 408 . 416 down to the switching mechanism 410 to be addressed. Preferred is the most central part of the zone 440 directly above the first or the second pen 408 . 416 arranged.

With reference now to the 12 to 15 a second exemplary switch end cap is shown and generally with 500 designated. The switch end cap 500 has a different configuration as the switch of the type of rocker, which in 2 is shown. The switch end cap 500 has a pair of switching assemblies 510 of the type of a bellows attached to an outer shell 520 the switch end cap 500 are coupled. The outer shell 520 houses electrical switching components 530 , like circuit boards 532 which generally act to provide switching signals when actuated by the user. Each of the circuit cards 532 has two depressible contact surfaces 534 showing the signals typically as a result, that a circuit due to the depression of one of the pads 534 closed, deliver.

Each switching arrangement 510 includes a switch holder 510 , a pair of bellows 514 and an upper seal 516 , Unlike the einkörprige switching element 82 of the type of a seesaw 2 uses the switching arrangement 510 two separate bellows 514 which act as depressible buttons to cause a signal to be generated. By the spatial separation of the bellows 514 the risk that the user will depress both buttons is greatly reduced. To the switching arrangements 510 has the outer shell 520 a pair of spaced openings 522 trained in itself. The openings 522 should be complementary forms relative to the bellows 514 to have. In the exemplary embodiment, the bellows 514 ring-like shapes, and therefore and the openings 522 generally annular in shape. The openings 522 should also be sized so that they are the bellows 514 absorb so that at least a portion of the bellows 514 extending through it.

Each switch holder 512 is above a respective circuit card 532 arranged. Accordingly, are the dimensions and shape of the switch holder 512 preferably complementary to the circuit card 532 , In the exemplary embodiment, both the switch holder 512 as well as the circuit card 532 a generally rectangular shape. The switch holder 512 has a first surface 540 and an opposite second surface 542 that the circuit card 532 is facing. The first surface 540 has a first platform formed on it 544 , The platform 544 has a planar area and also has a pair of raised stepped sections 546 trained on it. Each graduated section 546 is of a pair of superimposed concentric rings of varying diameters, as best in FIGS 12 and 13 shown. The larger diameter ring is the lowest ring to the other smaller diameter ring formed on the lowermost ring so as to form a protruding structure resting on the first platform 544 is formed.

Each graduated section 546 has an opening formed by him 550 , The opening 550 extends completely through the switch holder 512 , The graduated sections 546 are spaced apart so that a gap is formed between them. The graduated sections 546 are spaced so that they are generally axially aligned and over the contact surfaces 534 the circuit card 532 are arranged. As a result, the openings 550 axially with the contact surfaces 534 aligned when in the assembled state of the holder 512 over the circuit board 532 is arranged. How best in the 12 and 13 shown, lies the first surface 540 of the owner 512 at the upper seal 516 on, with the pair of stepped sections 546 axially aligned with and below the openings 522 is arranged in the outer shell 520 are formed. Part of the outer ring of the stepped section 546 can easily from the outer shell 520 protrude.

The 14 and 15 best illustrate the embodiment of the exemplary bellows 514 , 14 is a side elevation view of the bellows 514 and 15 is a cross-sectional view of the bellows 514 , The bellows 514 has a body 515 with an upper section 560 acting as a contact surface between the user's finger or thumb and the bellows 514 serves when it is depressed or released. The body 515 also has a lower section 562 which is at a respective graduated section 546 is present and adapted to him. Between the upper section 560 and the lower section 562 has the body 515 of the bellows a number of one-piece folds 566 , In the exemplary embodiment, the pleats are 566 in the form of a ring and spaced from each other. The diameter of the folds 566 is preferably approximately equal to the diameter of the upper and lower sections 560 . 562 ; however, the body has 515 a smaller diameter between the folds 566 , The wrinkles 566 thus form a generally accordion-like structure.

The wrinkles 566 give the bellows 514 feather-like characteristics, as the accordion-like structure folds when pressure on the upper section 560 is given. Once the pressure from the upper section 560 is taken away, the compressed wrinkles stretch 566 out, so she's the brat 514 return to their original state. In an exemplary embodiment, the bellows 514 made of a folded metallic material; however, other materials may be used as long as the materials are the bellows 514 provided with the above-described spring-like properties. For example, the bellows 514 be formed of nickel with a gold coating, or it may be formed of beryllium copper. In an exemplary embodiment, the thickness of the metallic bladder is from about 0.0127 mm to about 0.0502 mm (about 0.0005 inches to about 0.002 inches).

As it is best in 15 shown is the bellows 514 a pin 570 which is at the top section 560 is attached. The pin is preferred 570 integral with the upper section 560 educated. The body 515 of the bellows 514 has a central compartment formed therein, the folds 566 surround the central compartment and extend radially therefrom. The central compartment is open only on the second section 562 and is designed so that the pin 570 through the central compartment and through the opening in the lower section 562 is formed extends. In a first uncompressed position, as in the 14 and 15 As shown, a lowest peak extends 572 of the pin 570 under the lower section 562 , The pin 570 has a generally annular cross-section with different diameter in different sections along the length of the pin 570 , More precisely, the pin has 570 an annular flange 578 that has a larger diameter than the surrounding sections of the pin 570 Has. The annular flange 578 thus defines a first shoulder 579 and a second shoulder 580 closer to the bottom top 572 is. The pin 530 has a slight bevel from the second shoulder 580 to the lowest peak 572 ,

Because the pin 570 with the upper section 560 is connected and movable within the central compartment, cause a force on the upper section 560 is abandoned, and the consequent squeezing of wrinkles 566 that the pin 570 is directed down through the central compartment. This leads to that even a greater length of the pin 570 below the lower section 562 protrudes when the bellows 514 in this compressed position. As it is best in the 13 and 15 is shown, the pin is 570 inside the opening 550 taken up by the switch holder 512 is formed. The opening 550 has a diameter that is slightly larger than the diameter of the annular flange 578 , In the uncompressed position and when the switch end cap 500 is composed, the lower tip extends 572 not below or just slightly below the second surface 542 of the owner 512 , Because the openings 550 of the switch holder 512 axially with the contact surfaces 534 are aligned, the pins are 570 also axially with the contact surfaces 537 aligned. The contact surfaces 534 the circuit cards 532 are preferably collapsible domes, the circuit being closed when one of the domes has collapsed. The dome to be collapsed is a self-returning structure in that once a force causing the dome to collapse is removed, the dome returns to its initial un-collapsed position.

The bellows 514 are over the stepped sections 546 of the owner 512 arranged using conventional techniques so that the bellows 514 to the stepped sections 546 are coupled. The central compartment of the body 515 thus takes part of the upgraded section 546 of the owner 512 on what it allows the bellows 514 simply located and with the holder 512 can be coupled. The upper seal 516 is over the bellows 514 arranged and continues to secure the bellows 514 within the forest. The upper seal 516 has a pair of spaced openings 517 which the bellows 514 take up, with a considerable size of the bellows 514 above the upper seal 516 extends in the assembled, uncompressed position. The upper seal 516 is inside the outer shell 520 arranged so that they on an inner surface of the outer shell 520 is applied. The wrinkles 566 of the bellows 514 preferably extend above the outer surface of the outer shell 520 ; however, have the openings 522 the outer shell 520 a diameter which the bellows 514 accommodates, and thus the bellows 514 squeezed and continued into the opening 550 on the circuit card 532 to be driven.

The compression of the bellows 514 is caused by the bellows 514 against the stepped section 546 of the owner 512 is compressed. This compression allows the lowest peak 572 of the pin 570 on the circuit card 572 to be driven, and more precisely expresses the bellows 514 to a degree together that the lowest peak 572 in contact with the contact surface 534 is driven. This causes the contact surface 534 (Dome) coincides and the switching signal is generated. Thus, in this embodiment, the circuit arrangement 510 is formed from a folded metallic element which has spring-like properties which allow the bellows 514 is compressed under force and then returns to its initial, uncompressed position once the force has been removed. The upper seal 516 preferably forms a barrier which prevents unwanted material from entering the interior of the outer shell 520 entry.

Because the bellows 514 Made of a metal is the bellows 514 resistant to puncturing objects used in normal use of the surgical handpiece and instruments (eg, wire brushes) used in a normal cleaning operation (eg, a sterilization process). The bellows 514 Also forms a permeability barrier, which the water vapor and gas passage through the bellows 514 prevented. Therefore, the bellows offers 514 all of the advantages described hereinabove with respect to prior embodiments of switching elements having permeability barriers formed therein.

It will be understood that although the foregoing embodiment is a bellows element 514 has been extensively described, other types depressible switching elements can be used as long as the switching elements move from an uncompressed position under an applied force in a compressed position and then automatically return to the uncompressed position, once the applied force has been removed. For example, instead of wrinkles 556 , the compressible and collapsible switching element may have a wall structure to be collapsed (eg see Figs 11 ) which collapses under the applied force but returns to the uncompressed position once this applied force is removed. This may be a metallic switching element having a dome structure similar to that of 11 or may have a different configuration to collapse.

16 FIG. 14 illustrates still another embodiment similar to the embodiment shown in FIGS 12 - 15 is shown. In this embodiment, the bellows 514 no cones 570 ( 15 ). Instead, the brat has 514 a hollow inner compartment, and the part of the bellows 514 that on the contact 534 the circuit card 532 is actually an inner surface of the upper section 560 of the bellows 514 ,

The contact 534 more preferably, a contact to be collapsed (eg a dome-type structure); however, a pin extends 535 from the contact 534 outward. The pin 535 is the pin 570 ( 15 ) similar in size and size, as it is designed to be in the opening 550 recorded in the stepped section 546 of the owner 512 is formed when the holder 512 right over the circuit card 532 is arranged. The pin 535 thus extends through the opening 550 and extends at least partially into the inner compartment of the bellows 514 , In the uncompressed position is the upper section 560 of the bellows 514 slightly above the top of the pin 535 spaced. When a force to the upper section 560 is applied, expresses the body 515 of the bellows 514 together, and the top section 560 makes contact with the pin 535 , Because the pin 535 even on a structure to be collapsed (the dome contact 534 ), causes the further application of force against the upper portion 560 that the pin 535 is driven down. This causes the dome structure (contact 534 ) collapses and the circuit is closed. A switching signal is then sent. Once the force is removed or the force decreases, the upper section moves 560 outward, as well as the pin 535 when the dome structure 534 expands.

Even though the invention in particular with reference to its preferred embodiments As has been shown and described, it will be understood by those skilled in the art be that on it different changes in shape and detail can be made without you removed from the scope of the invention.

Claims (11)

Depressible switching element ( 82 ) for use in a surgical handpiece ( 30 ) to an interior of the handpiece ( 30 ), wherein the switching element ( 82 ) comprises: a body ( 83 ) and a sidebar ( 85 ) around the body ( 83 ) to allow the body ( 83 ) is pressed lightly when pressed on it, and returns to its original position when released; and characterized by: a metallic layer ( 110 . 122 ) as a permeability barrier located at at least one location on at least one body ( 83 ) and sidebar ( 85 ) is arranged to provide a permeability barrier for the at least one location. Switching element ( 82 ) according to claim 1, wherein the body ( 83 ) in the form of a rocker type switch formed of an elastomer. Switching element ( 82 ) according to claim 1 or 2, wherein the layer ( 110 . 122 ) only on a lower side of the sidebar ( 85 ) in use to the interior of the handpiece ( 30 ). Switching element ( 82 ) according to claim 1 or 2, wherein the layer ( 110 . 122 ) only on one side ( 112 ) of both the body ( 83 ) as well as the sidebar ( 85 ) is arranged. Switching element ( 82 ) according to claim 1 or 2, wherein the layer ( 110 . 122 ) in an intermediate region of at least one body ( 83 ) and sidebar ( 85 ) is formed between its upper and lower surfaces. Switching element ( 82 ) according to one of the preceding claims, in which the peripheral edge strip ( 85 ) a thickness less than a thickness of the body ( 83 ), the layer ( 110 . 122 ) at least on a lower side of the sidebar ( 85 ) is formed. Switching element ( 82 ) according to claim 7, wherein the metallic layer ( 110 . 122 ) is a metallic coating having a thickness between about 0.127 μm (5 μ inches) and about 127 μm (0.005 inches). Switching element ( 82 ) according to one of claims 1 to 6, in which the layer ( 110 . 122 ) in one piece with at least one body ( 83 ) and sidebar ( 85 ) is formed. Switching element ( 82 ) according to one of claims 1 to 8, in which the layer ( 110 . 122 ) from an underside ( 112 ) of the body ( 83 ) and the sidebar ( 85 ) is spaced. Switching element ( 82 ) according to one of claims 1 to 8, in which the layer ( 110 . 122 ) directly to at least one body ( 83 ) and sidebar ( 85 ) is arranged adjacent. Switching element ( 82 ) according to one of the preceding claims, in which the edge strip ( 85 ) a number of folds formed in it ( 220 ) Has.