ES2278697T3 - FLEXIBLE SWITCHING ELEMENTS FOR MANUALLY OPERATED SWITCHES. - Google Patents

Abstract

Switching element (82) that can be pressed for use in a surgical handpiece (30) to seal an interior of the handpiece (30), the switching element (82) comprising: a body (83) and a skirt (85) that extends peripherally around the body (83) to allow the body (83) to sink easily when pressed and return to its original position upon release; and characterized by: a metallic layer (110, 122) as a permeability barrier arranged in at least one location of at least the body (83) or the skirt (85) to obtain a permeability barrier for the at least one location.

Description

Flexible switching elements for manually operated switches.

Background of the invention

This application refers to systems ultrasonic surgical and, more specifically, to elements switching that have watertight membranes that prevent gas and the water vapor come into contact with the sets of switching that are arranged inside a switching chamber internal shaped in a surgical handpiece.

It is known that scalpels can be used electric and lasers as surgical instruments to carry perform the double function of simultaneously performing the incision and soft tissue hemostasis by cauterization of the tissues and blood vessels. However, these instruments they use very high temperatures to get coagulation, causing the formation of steam and fumes, as well as splashes. In addition, the use of such instruments often causes relatively large areas of tissue that are damaged thermally

Cutting and cauterization are also known. of tissue using surgical instruments, for example, blades that vibrate at high speeds through drive mechanisms Ultrasonic In these instruments, a generator is provided Ultrasonic that produces an electrical signal for a voltage, specific current and frequency, for example, 55,500 cycles per second. The generator is connected by a cable to a piece of hand, which contains piezoceramic elements that form a ultrasonic transducer In response to a switch in the part handheld or to a foot switch connected to the generator by another cable, the generator signal is applied to the transducer, which It causes a longitudinal vibration of its elements. A structure connect the transducer to a surgical blade, which in this way vibrates at ultrasonic frequencies when the signal from the generator to transducer. The structure is designed to resonate at the selected frequency, thereby amplifying the movement initiated by the transducer.

For the purpose of operating the handpiece so that the blade vibrates or is operated in another way, the user manipulate a switching mechanism. The switching mechanism normally includes one or more switching button elements that the user presses to operate the blade. Because it is it is necessary to clean and / or check the handpiece after its utilization, the internal electronic components of the mechanism of switching must be tight to the outside environment of the piece of hand, in order to avoid damage to electronic components during cleaning, use, handling, or maintenance of the same. This is particularly true in parts that are autoclavable and / or submersible. Consequently, a membrane (for example, a flexible seal) that is part of the switching element to seal the electronic components of the switching mechanism, so that the handpiece can be cleaned and / or maintained without damaging the electronic components.

Normally, the switching element (which it has button parts) is formed by an elastic material, such as an elastomeric material, to obtain a sealing action between the switching element and the handpiece. By way of In general, elastomeric switching buttons do not constitute good barriers to moisture ingress (water vapor), especially for moisture ingress due to an operation of autoclave. Elastomeric materials are vulnerable to perforations by sharp instruments. Also, if the moisture passes through these elastomeric barriers during the autoclave operation, moisture has no means to escape quickly from the handpiece after the completion of the autoclave operation. The presence of moisture in a cavity inside the handpiece, in which the electronic components, may cause damage and / or bad operation of the handpiece or lead to wear premature.

When the switching element is formed as an elastomeric switching element, a integral flexible membrane may be arranged around the periphery of it. Frequently, reference is made to this flexible membrane like a "sheet" or skirt that allows the body of the switching element easily sinks when it is oppressed and return to its original after release. They exist at minus two disadvantages associated with the use of a sheet Fine elastomeric as part of the body of the switching element swingarm. First, resistance to perforation / tearing of the sheet area is limited, due to that the sheet area has a relatively cross section fine, and has limited durability to resist perforations by sharp instruments that come into contact with the flexible part (the sheet). Second, the finesse of the sheet membrane does not allow to obtain a very resistant seal, since air and moisture can pass through it. In other words, the sheet membrane has a permeability what high enough to allow air and moisture pass through it.

An example of the difficulties encountered in a switching element with high permeability occurs when the switching element is subjected to a process of autoclaved When the rocker switching element is used to seal an inner cavity of the handpiece, a autoclave vacuum can cause the air pressure inside the inner cavity is larger than outside the inner cavity. He switching element has a limited travel in one direction outward, and therefore cannot contain the pressure anymore high. Consequently, pressurized air escapes through the sheet membrane due to its relatively low permeability. It is also possible that the pressurized air can escape through other parts of the body of the switching element. However, during autoclave repressurization at a normal atmosphere, the pressure reduction inside the inner cavity causes the  Switching element deviate down. This makes the switching element be stretched down, similarly to when someone presses the switching element. In this way, the switching element equals the pressure, and a inadequate pressure differential that causes air to return to through the sheet membrane. This causes the element of switching remains in lower position without intervention of the user. This is not desirable, as it causes a non-drive. desired of the switching mechanism because the element of Switching is in a sunken position.

Although existing membranes result suitable for some applications, there is a need to give know improved membranes that constitute good barriers to entrance of humidity and that allow to obtain a good barrier for the gas vapor and the transmission of other gases (air), in addition to a improved puncture resistance.

In US 5,226,904 and US 4,373,124, give examples of switching elements of the state of the technique. US 5,226,904 forms the basis of the preamble of the attached claim 1.

Summary of the Invention

This application refers to elements of switching as defined in claim 1, which control the flow of fluid (for example, water vapor flow and gases, such as air) through the switching elements which are used to seal an inner cavity of a piece of surgical hand, each providing an element that can be pressed to operate the handpiece. The elements of switching allow for improved sealing properties that prevent the transmission of fluids to the entire element of switching, or at least towards a treated part thereof (by example, a skirt), and towards the inside and outside of the chamber Internal switching watertight. The switching elements are also resistant to perforation due to contacts by cleaning tools or instruments and the like.

The switching elements result particularly useful in handpieces that are autoclavable. The autoclave pressures and voids can induce a gas flow and of water vapor through the membranes of the elements of conventional switching and, specifically, through the fine skirt part of them. The present application gives know several methods to control the flow of gas and steam from water through a switching element that can be pressed (specifically, the skirt part), so that the piece of hand can be used in an autoclave environment and in other adverse conditions without experiencing the disadvantages associated with Conventional elements

Other features and advantages will result evident from the following detailed description, interpreted in combination with the accompanying drawings.

Brief description of the drawings

The above and other features they will be more easily understood from the following detailed description and drawings of embodiments illustrative, in which:

Figure 1 is an illustration of a console for an ultrasonic surgical cutting and hemostasis system as well as of a handpiece and a foot switch according to a example embodiment;

Figure 2 is a cross-sectional view. showing an example switching end cover;

Figure 3 is a top perspective view. of an example switching element for use in the switching end cover of figure 2;

Figure 4 is a bottom perspective view. of the switching element of Figure 3;

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

Figure 5A is a cross-sectional view. fragmentary taken along line A-A of the figure 5;

Figure 6 is a cross-sectional view. fragmentary of a switching element according to another embodiment for example, in which a substrate is arranged between the element of switching and permeability barrier;

Figure 7 is a top perspective view. of a switching element according to another example embodiment;

Figure 8 is a bottom perspective view of a switching element according to another example embodiment;

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

Figure 9 is a bottom perspective view of a switching element according to another example embodiment;

Figure 9A is a cross-sectional view. fragmentary taken along line A-A of the figure 9;

Figure 10 is a cross-sectional view. partially fragmented of a switching end cover which has a vent shaped therein;

Figure 11 is a cross-sectional view. of a durable switching assembly according to another embodiment;

Figure 12 is an exploded view of a switching end cover according to another embodiment of example;

Figure 13 is a cross-sectional view. of the switching end cover of Figure 12 in the state mounted;

Figure 14 is a side elevational view of a bellows switch used in the end cover of switching of figure 12;

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

Figure 16 is an exploded view of a switching end cover according to another embodiment of example.

Description of illustrative example embodiments

Referring first to the figure 1, a cutting system and surgical hemostasis is shown according to a embodiment, generally indicated as 10. In the embodiment For example, system 10 is an ultrasonic surgical system. He system 10 includes a console or housing 20 containing a ultrasonic generator (not shown) and a control system located inside the console 20, which is part of the system 10. A first cable 22 connects the console 20 to a handpiece 30, and it serves to obtain an electrical connection between them. He First cable 22 includes a first set of wires (not shown) that allow electric power, that is, the current of drive, be supplied from console 20 to the part handheld 30, where it imparts an ultrasonic longitudinal movement to a surgical instrument 11. The surgical instrument 11 is preferably a scalpel blade or shear. This instrument 11 can be used for dissection and cauterization simultaneous tissue.

The supply of ultrasonic current to the handpiece 30 is controlled by a switching mechanism 40 arranged inside the handpiece 30. As it is will describe in more detail hereafter, the mechanism of switching 40 is electrically connected to console 20, more specifically, to the generator thereof, by one or more wires (not shown) of the first cable 22. In addition the generator can be optionally and additionally controlled by a foot switch 50 which is connected to the console 20 by a second cable 60. Therefore, during use, a surgeon may apply a Ultrasonic electrical signal to handpiece 30, causing the instrument 11 vibrate longitudinally at an ultrasonic frequency,  by actuating the switching mechanism 40 in the handpiece 30 or foot switch 50. The mechanism of switching 40 is operated by the surgeon's hand, and the switch Standing 50 is operated with the surgeon's foot.

The console 20 further includes a liquid crystal display device 24, which can be used to indicate the level of cutting power in different ways, such as the percentage of maximum cutting power or the numerical power levels associated with the cutting power . The liquid crystal display device 24 can also be used to display other system parameters. In the console 20 there is also a power switch 26 and an "on" indicator 28 to allow the user additional control of the operation of the system 10. Other buttons and control switches, generally indicated as 70, control other functions other than the system 10, and may be located on the front panel of the console 20. When the power is applied to the ultrasonic handpiece 30 by actuating the switching mechanism 40 or the switch 50, the scalpel or surgical instrument 11 vibrates with an amount of longitudinal movement that varies proportionally with the amount of drive power (current) applied, which can be selected in an adjustable manner by the
Username.

Referring in this case to figures 1 to 4, in figure 2 a switching mechanism 40 is shown in more detail. The handpiece 10 is formed by a cover of switching end 90 that is attached to a body part of hand 92. Switching mechanism 40 includes multiple electrical components, for example, one or more circuit boards 80, and also includes one or more switching elements that can be oppressed 82, which are manipulated by the user for the activation or deactivation of the switching mechanism 40. For illustration purposes only, each switching element 82 It is shown in the form of a toggle switch; no However, it will be understood that switching element 82 can understand any number of types of switching elements which can be pressed 82, and is not limited to a switch of tilting type Example switching element 82 includes a body 83 (in this case a tilting body) and a skirt 85 extending peripherally around the body 83. The switching element 81 serves to seal an interior of the part handheld 10, and therefore acts as a vapor barrier for water and gas (i.e. a liquid permeability barrier and gases). Preferably, body 83 and skirt 85 act as permeability barriers. The switching element 82 includes furthermore a pair of legs 87 extending outwardly from body 83 to engage a contact (not shown) to cause actuation of switching mechanism 40 (figure one). The legs 87, in an uncompressed state, extend preferably not beyond a plane containing the surface bottom of skirt 85. Because legs 87 are formed preferably by an elastomeric material, such as body 83 and the skirt 85, a force exerted on the upper surface of the body 83 on legs 87 causes respective legs 87 are displaced downward, so that they extend beyond the plane containing the bottom surface of the skirt 85. This is the compressed position of switching element 82.

In the illustrated embodiment, the cover of switching end 90 includes two switching elements opposites 82 that are coupled to the end cover of switching 90. Switching end cover 90 has a outer casing 94 housing electrical switching components, such as circuit boards 80. Because each element of switching 82 is in communication with the switching mechanism 40, there are openings formed in the outer shell 94 for allow switching element 82 to engage the mechanism switching 40, so that the signals are generated by the switching mechanism 40 and transmitted to console 20 to allow actuation of handpiece 10.

Handpiece 10 is designed preferably for use in a surgical system, such such as the one disclosed in the European patent application EP-A-1 199 047 (Agent Ref: P028404EP) (which claims the priority of the USSN document 09/693621), presented at the same time as this request.

And handpiece 10 is described in greater detail in European patent application number EP-A-
1 199 040 (Agent Ref .: P028413EP) (which claims the priority of document USNN 09 / 693.549).

In one aspect, an element of enhanced switching 82, in the form of a switching button elastomeric swinging type. It will be understood that although in the present memory is used the term "elastomeric", the element of switching 82 may be formed by other suitable plastics, for example, a thermoplastic. In addition, although the description is will focus on switching elements used in mechanisms of switching, it will be appreciated that other types of components of plastic, such as seals, walls or other components, may be replaced by switching membranes. Also though switching elements of swing type example, it will be understood that the scope of the This application covers other types of switching elements. Accordingly, the description and illustration of the elements of swinging type switching are merely by way of example and not limiting

Referring to figures 3 to 5A, in a example embodiment, a metallic layer 110 is applied in the switching element of elastomeric tilting type 82, such as shown in Figure 5. Preferably, skirt 85 is integrally conformed with body 83. More specifically, the metallic layer 110 is applied on a lower face 112 of the element elastomeric tilt switching 82. Layer 110 may be formed by any number of suitable metal materials, by example, aluminum, gold, titanium, platinum. Layer 110 is shaped of a thin layer of metal that is applied to predetermined parts of the lower face 112 of the body 83 and the skirt 85. For example, the entire lower face 112 (including body 83 and the skirt 85) may be covered by metallic layer 110, which is a thin coating (for example, the thickness can be about 0.127 µm (5 µm) to about 12.7 µm (0.0005 inches). Alternatively, the sheet metallic 110 is only arranged in the skirt 85 of the element switching 82. The metallic layer 110 drastically reduces the water and gas vapor transmission rate of the treated part, by example, the bottom face 112. Because the layer 110 is very thin, the layer 110 is flexible and does not hinder the flexibility of the piece elastomeric (the switching element 82). The presence of the metallic layer 110 improves the watertight properties of the element of switching 82. Metal layer 110 is not limited to its application to only the bottom face 112, but the layer metallic 110 can also be formed in an intermediate layer of the switching element 82 between the upper surface and the underside 112. The metallic layer 110 may be shaped only in an intermediate layer of the skirt 85. The metallic layer 110 can also be applied to the upper surface of the element 82 by itself, or in combination, arranged on the underside 112 or in an intermediate layer. The metallic layer 110 can be applied using conventional techniques, including use of a spray apparatus or other type of equipment that serves to apply a thin metallic layer, preferably of uniform thickness, to a body. Other techniques that can be used to apply the metallic layer 110 include, but not in a manner limiting, ion beam deposition, vapor deposition of metal, and chemical vapor deposition.

In another embodiment, shown in Figure 6, a thin flexible substrate 120 is provided with a metallic layer 122 and covered by it. The substrate 120 is formed preferably by a flexible material, such as polyurethane, vinyl, silicone, a thermoplastic elastomer, fluoride polyvinylidene, polyparaphenylene terephthalamide, polyimide, and a combination of any of the above materials. For example, a polyimide film can be coated with a resin of FEP fluoropolymer to obtain a moisture barrier and a sliding surface that reduces the tendency of a tool to pierce the element. In an exemplary embodiment, the substrate 120 is about 12.7 µm (0.0005 inch) thick at about 76.2 µm (0.003 inches). Metal layer 122 may be formed by any number of suitable metals, including, but not limited to, aluminum, gold, titanium, and platinum Preferably, the metallic layer 122 is formed by a metal that allows the metallic layer 122 to be thin, and that at at the same time, it allows the metallic layer 122 to have rates of reduced water vapor and gas transmission. The thickness of the metallic layer 122, in one embodiment, is between about 0.127 µm (5 µm) and about 12.7 µm (0.0005 inch). The metallic layer 122 is formed in a first surface 124 of the thin flexible film substrate 120. A second opposite surface 126 of the flexible film substrate fine 120 is fixed to the bottom face 112 of the switching element tilting 82 or faces the same when the handpiece 30. In one embodiment, the substrate 120 is adhered to the lower face 112 of the switching element 82 by means of a adhesive. The thin flexible film substrate 120 may be located on the underside 112 or just below it. By example, the thin flexible film substrate 120 may be in foil-like contact with the rocker switching element elastomeric 82, so that the metallic layer 122 is oriented in the opposite direction to the toggle switching element elastomeric 82, as shown in Figure 6. The substrate of thin flexible film 120 can also be located nearby, although separate, from the elastomeric rocker switching element 82. It will be understood that the substrate 120 can be applied to parts selected from the bottom face 112. For example, the substrate 120 may be applied only to the underside of skirt 85, or it can be applied to the entire lower face 112.

Any pressure differential problem that occurs through element 82 (such as during a process autoclave cleaning) can be reduced to levels insignificant by decreasing the volume of air in the watertight switching chamber under element 82. Filling of the empty area under element 82 reduces the amount of air under element 82 that is influenced by heat and pressure, thereby reducing the pressure differential across of element 82, and then reducing the adverse effects on the switching element 82. This can be seen in a manner special in applications, for example, an autoclave process, in which a force acts on element 82. It will be appreciated that a small area under element 82 is necessary to allow that the legs 87 or the like move when the element 82 is pressed or when it returns to an uncompressed position. environment to reorganize and / or organize more tightly and / or refine the molecular microcrystalline structure of the element of elastomeric switching 82. This results in a decrease of porosity, water vapor transmission rates and gas, and improves the sealing capacity of the switching element elastomeric 82. A proper technique is to introduce the elastomeric switching element 82 in a treatment of thermally controlled progressive liquid nitrogen. Other benefit of this treatment is an improvement in endurance (robustness) and in the puncture resistance of the element of elastomeric switching 82. This results particularly beneficial for the durability of the fine elements that are strongly flexed or subjected to instrument action pointed.

The flexibility and ability to move they can be improved by forming folds or undulations 220 in the perforation-resistant skirt 210, as shown in the figure 8A. Due to the superior puncture resistance of the perforation-resistant skirt 210, the flexible zone is substantially more puncture resistant than the sheet elastomeric (skirt). These folds / undulations 220 allow get a spring-like return action that returns the tilting element 200 to its upward position when the tilting element 200 stops being pressed. These folds / corrugations 220 may also allow obtaining an action of instantaneous stop that allows to obtain a tactile reaction for the user. If necessary, springs or vaults (not shown) below the tilting element 200 for complement or fully constitute the means for a tilting upward return of the tilting element 200 when This one is released. Plastic springs / domes may result especially useful, due to its non-corrosive nature in presence of steam and heat. In addition, the skirt resistant to perforation 210 has an improved resistance to air flow at through it, thereby reducing the permeability of the tilting element 200. This reduced permeability facilitates a proper behavior of the tilting element during and after of autoclaving.

In addition, the film selection for form the perforation-resistant skirt 210 or a supplementary coating that has a sliding surface with a relatively low friction (compared to an elastomer which has high friction) prevents the formation of grooves / perforations during cleaning / handling. Materials with relatively low friction include, but not limitedly, polyimides, polyesters, materials polytetrafluoroethylene, and titanium nitrate. For example, the instruments, such as brushes, that come into contact with the sliding element are more likely to slide by the element that to pierce it, compared to a normal elastomeric element. Therefore, the fact of forming the skirt resistant to perforation 210 so that at least one surface thereof has a low friction surface, improves resistance to perforation of the perforation-resistant skirt 210. It can also an additional surface treatment such as a ionic implantation.

Another method to improve the element of 200 switching for durability and resistance Improved to the passage of air / humidity is to maintain the membrane of sheet intact, except on the surfaces of switching element 200 predetermined surface treated by using a proper surface treatment process. Plus specifically, at least the area of the sheet membrane (skirt) is superficially treated and preferably the treatment Superficial is carried out inside (lower face) and / or in the outside of the rocker switching element 200. For example, the entire lower face can be treated superficially. Surface treatments that can used include metal coatings (such as aluminum, gold, titanium, platinum, etc.).

As mentioned above, the skirt fineness (i.e. a flexible seal) cannot provide a very robust seal, since air and moisture They can pass through it. In other words, the skirt permeability is high in configurations conventional. Although it is desirable that the skirt has a low permeability, there is usually a certain degree of permeability. The amount of gas / moisture that passes through the skirt and other parts of the element depends on the pressure difference between each Element side

Switching element 82 (Figure 3) is designed to obtain a substantial displacement in one direction out / up and in an inward / downward direction. This symmetric displacement capability reduces the differential of pressure through the element, thereby reducing the flow of gas / moisture through the element. By reducing the flow through the element, the tilting element is able to return to its normal after autoclaving, unlike conventional tilting elements, which tend to remain in lower position without user intervention, as it has been previously described. Another benefit of flow reduction is greater reliability, since moisture does not run so easily into the sealed chamber to potentially affect the components.

According to the present invention, the displacement Symmetric can be obtained by various means. An example is the use of folds or corrugations 220, as shown in switching element 200 of Figure 8A. The utilization of folds / corrugations 220 in the area of the skirt 210 allows a upward movement, as well as a downward movement. Other method is to provide the element with an adequate arrangement that allows the expansion of the element both outward and inward. In addition, an elastic material can be used, for example, polyurethane, which easily lengthens, to form the element tilting, thus allowing the tilting element to be expand out. In all these embodiments, the differential pressure across the element is controlled by a movement suitable of the tilting element in both directions.

Referring in this case to Figure 11, a durable and indicated switching set is shown general as 400. Switching assembly 400 can be pressed easily with light pressure, although it has a housing relatively thick outer 402 that is resistant to damage by drilling and gas flow. For example, and according to one embodiment For example, the thickness of the outer shell 402 is about 1,016 millimeters to about 1,524 millimeters. The outer shell 402 is shaped like a shell with a dome of bubble to be pressed with the fingers, and can be made of various materials, including, but not limited to, polyimides, polyesters and other suitable materials. The housing exterior 402 has two active zones, that is, a first zone 404 and a second zone 406. Due to the dome shape, the housing exterior 402 can be easily deformed by the pressure of the finger to cause the switching mechanism to operate 410. The first zone 404 has a first leg 408 that extends from the outer housing 402 to the switching mechanism 410. An end 407 of the first leg 408 is connected, preferably integrated, to the outer shell 402, and one end opposite 409 is arranged near the switching mechanism 410, although not in contact with it, in the rest position shown in Figure 11. The second end 409 has a first 412 contact pad that attaches to a first pad switching 414 formed on a PCB 420, which forms a part of the switching mechanism 410. Preferably, the first switching pad 414 is axially aligned with the first contact pad 412, so that the oppression of the first zone 404 makes the first contact pad 412 contact the first switching pad 414, causing the actuation of the switching mechanism 410.

Similarly, the second zone 406 has a second leg 416 extending from the outer shell 402 towards the switching mechanism 410. One end 417 of the second leg 416 is connected, preferably integrally, to the outer shell 402, and an opposite end 419 is arranged near of the switching mechanism 410, although not in contact with the same, in the rest position shown in figure 9. The second end 419 has a second contact pad 422 that is attaches to a second switching pad 424 formed in PCB 420, which forms a part of the switching mechanism 410. Preferably, the second switching pad 414 is axially aligned with the second contact pad 422, so that the oppression of the second zone 406 causes the second contact pad 422 comes into contact with the second switching pad 424, causing the drive of the switching mechanism 410.

Optionally, there may be a central support leg 430 to reduce a drive involuntary when the center of the housing is held or pressed exterior 402. The central support leg 430 extends from the outer housing 402 towards switching mechanism 410. In the resting position of figure 11, central support leg 430 rests against an inactive part of the switching mechanism 410 or near it. In addition, the first and second zones 404, 406 they can have their own flexible membrane (not shown) to reduce additionally the oppression drive pressure. The housing Example exterior 402 shows a stepped portion 440 arranged in the first and second zones 404, 406. The staggered parts 440 allow to obtain a contact point for the fingers of the user to be oppressed, so that the first and second respective legs 408, 416 are moved down towards the switching mechanism 410. Preferably, the most central part of zone 440 is located directly on the first or the second leg 408, 416.

Referring in this case to the figures 12 to 15, a second switching end cover is shown example, generally indicated as 500. The cover of switching end 500 has a different configuration than the of the rocker switch shown in Figure 2. The 500 switching end cover has a couple of sets of bellows type switch 510 that are coupled to a housing exterior 520 of the switching end cover 500. The 520 outer housing houses electrical switching components 530, such as 532 circuit boards, which generally work to obtain switching signals when activated by the Username. Each of the 532 circuit boards has two 534 contact pads that can be pressed and that allow signals to be obtained, usually as a result of closure of a circuit due to the oppression of one of the pads of contact 534.

Each switching assembly 510 includes a switching retainer 512, a pair of bellows 514, and an upper gasket 516. Unlike the swinging switching element 81 of a single body 81 of Figure 2, the switching assembly 510 uses two separate bellows 514 that act as switching buttons that can be pressed to generate a signal. By physically separating the bellows 514, the risk of the user pressing both switching buttons is greatly reduced. To accommodate the switching assemblies 510, the outer housing 520 has a pair of separate openings 522 formed therein. The openings 522 should have complementary shapes with respect to the bellows 514. In the exemplary embodiment, the bellows 514 have an annular shape and, therefore, the openings 522 generally have an annular shape. The openings 522 could also be sized to accommodate the bellows 514 so that at least a portion of the bellows 514 extends through the
same.

Each switching retainer 512 is arranged on a respective circuit board 532. Accordingly, the dimensions and shape of the switching retainer 512 are preferably complementary to circuit board 532. In the example embodiment, the switching retainer 512 and the plate 532 circuits generally have a rectangular shape. He switching retainer 512 has a first surface 540 and a second opposite surface 542 that is oriented towards the plate of circuit 532. The first surface 540 has a first platform 544 formed therein. The first 544 platform It has a flat part and also has a pair of staggered parts high 546 formed in it. Each stepped part 546 It is formed by a pair of stacked concentric rings of different diameters, as can be best seen in the figures 12 and 13. The ring with the largest diameter is the lowest ring, the other ring being formed with a smaller diameter on the lowermost ring, in order to form a structure that extends formed on the first platform 544.

Each stepped part 546 has an opening 550 formed through it. The opening 550 extends entirely through switching retainer 512. The parts staggered 546 are separated from each other, so that a interstitium between them. The staggered parts 546 are separated, so that in general they are axially aligned and arranged on the contact pads 534 of the plate circuit 532. Consequently, openings 550 are aligned axially with contact pads 534 when the retainer 512 is arranged on circuit board 532 in the assembled state. As best seen in Figures 12 and 13, the first surface 540 of retainer 512 is supported against the seal upper 516, the pair of staggered parts 546 being aligned axially with openings 522 formed in the outer shell 520 and arranged below them. A part of the ring outside of stepped part 546 may protrude slightly from the outer shell 520.

Figures 14 and 15 best illustrate the configuration of example bellows 514. Figure 14 is a side elevation view of bellows 514, and Figure 15 is a view in cross section of bellows 514. Bellows 514 has a body 515 with a top 560 that serves as the surface of contact between the user's finger or thumb and the 514 bellows when It is oppressed or released. The body 515 also has a part bottom 562 that rests against a stepped part 546 respective and coupled to it. Between the top 560 and the bottom 562, the bellows body 515 has a series of integral folds 566. In the exemplary embodiment, the folds 566 have an annular shape and are separated from each other. The diameter of the folds 566 is preferably approximately equal to diameter of the lower and upper parts 560, 562; However, the body 515 has a smaller diameter between the folds 566. The folds 566 thus form a structure in general by way of accordion.

The 566 folds grant bellows 514 spring-like features, since the structure by way of accordion folds up when pressure is applied to the top 560. As soon as pressure on the part is no longer applied upper 560, the 566 compressed folds expand, making thus return the bellows 514 to its original state. In a example embodiment, bellows 514 is made of a material metal; however, other materials can always be used that the materials give bellows 514 the characteristics to Spring mode described above. For example, bellows 514 it can be made of nickel with a gold coating, or it can be be formed by beryllium copper. In an example embodiment, The thickness of the metal bellows 514 is approximately 0.0127 mm at approximately 0.0508 mm (from approximately 0.0005 inches to approximately 0.002 inches).

As can be best seen in Figure 15, The bellows 514 has a leg 570 fixed to the upper part 560. Preferably, leg 570 is integrally formed with the upper part 560. The body 515 of the bellows 514 has a central compartment formed therein, with the folds 566 surrounding the central compartment and extending radially from it. The central compartment is open only in the second part 562, and is configured so that leg 570 is extends through the central compartment and through the shaped opening at the bottom 562. In a first uncompressed position, as shown in figures 14 and 15, a lowermost tip 572 of the leg 570 extends below the bottom 562. Leg 570 has a cross section in general annular of variable diameter in different parts along of leg length 570. More specifically, leg 570 it has an annular fin 578 that has a diameter greater than parts of leg 570 that surround it. The ring fin 578 defines of this way a first flange 579 and a second flange 580, more near the lowermost tip 572. Leg 570 narrows slightly from the second flange 580 towards the tip plus lower 572.

Because leg 570 is connected to the top 560 and can move inside the central compartment, a force applied to the top 560 and the resulting compression of the folds 566 causes the leg 570 scroll down through the compartment central. This makes an even longer leg length 570 protrudes below the bottom 562 when bellows 514 It is in compressed position. As can be best seen in Figures 13 and 15, leg 570 is housed inside the opening 550 formed through switching retainer 512. The opening 550 has a diameter that is slightly larger than ring fin diameter 578. In an uncompressed position, and when the switching end cover 500 is mounted, the lowermost tip 572 does not extend below the second surface 542 of retainer 512, or only extends slightly below it. Because the openings 550 of the switching retainer 512 are axially aligned with the contact pads 534, legs 570 are also left aligned with contact pads 534. The pads of Contact 534 of circuit boards 532 are preferably domes that can be compressed, so that the circuit is completed when one of the domes is compressed. The dome that can compressing is a structure that automatically returns to its initial position not compressed once the force that causes the Compression of the dome is removed.

The bellows 514 are arranged on the stepped parts 546 of retainer 512 by techniques conventional, so that the bellows 514 are coupled to the stepped parts 546. The central compartment of the body 515 thus houses a part of the stepped part 546 of the retainer 512, allowing bellows 514 to be arranged and easily fit into retainer 512. The top seal 516 is It has 514 bellows and additionally fixes 514 bellows inside the general structure. The top seal 516 has  a pair of separate openings 517 housing the bellows 514, a significant part of the bellows 514 extending over the top seal 516 in a non-compressed mounted position. Board upper 516 is arranged inside the outer shell 520, so that it rests against an inner surface of the outer shell 520. The folds 566 of the bellows 514 are preferably extend over the outer surface of the outer shell 520; however, the openings 522 of the housing exterior 520 have a diameter that houses the bellows 514, and so both bellows 514 can be compressed and displaced additionally inside the opening 550 towards the circuit board 532

The compression of the bellows 514 is caused by the compressed bellows 514 against stepped part 546 of the retainer 512. This compression allows the lowermost tip 572 of leg 570 be displaced towards circuit board 532 and, more specifically, that the bellows 514 is compressed to such a degree that the lower tip 572 is displaced until it enters contact with the contact pad 534. This causes the contact pad 534 (dome) is compressed and the signal. Thus, in this embodiment, the set of switching 510 is formed by a folded metal element that It has spring-like features and allows the bellows 514 is compressed under a force and then returns to its position initial not compressed once the force is no longer applied. Board upper 516 preferably forms a barrier that prevents entry of unwanted material in the outer shell 520.

Because bellows 514 is made of metal, bellows 514 is puncture resistant by objects which are used in normal use of the surgical handpiece, and of instruments (e.g. wire brushes) used in a normal cleaning operation (for example, in a process of sterilization). The bellows 514 also allows to obtain a barrier of permeability that prevents the transmission of water vapor and gas to through bellows 514. Therefore, bellows 514 offers all advantages described above, referring to the preceding embodiments of switching elements that have permeability barriers formed therein.

It will be understood that, although the previous embodiment has been described including bellows elements 514, can used other types of switching elements that can be pressed, provided that the switching elements can move freely from an uncompressed position to a position compressed under the application of a force, and then return automatically to the uncompressed position once it stops apply force For example, instead of having 556 folds, the switching element that can be compressed and pressed can have a wall structure that can be compressed (see, for example, figure 11) that is compressed under the application of a force, but return to its uncompressed position once This force is no longer applied. It can be an element metal switching with a dome structure similar to the of Figure 11, or may include a configuration that may Compress differently.

Figure 16 illustrates another embodiment that is similar to the embodiment shown in figures 12 to 15. In this embodiment, the bellows 514 does not include a leg 570 (Figure 15). In instead, bellows 514 has a hollow interior compartment, and the part of bellows 514 that contacts contact 534 of the plate circuit 532 is actually an inner surface of the part upper 560 of bellows 514.

Contact 534 remains preferably a contact that can be compressed (for example, with a configuration dome type); however, a leg 535 extends towards outside from contact 534. Leg 535 is similar to leg 570 (figure 15) in its dimensions and size, since it is designed to staying in opening 550 formed in stepped part 546 of retainer 512 when retainer 512 is positioned so suitable on circuit board 532. Leg 535 extends from this mode through opening 550, and extends at least partially inside the bellows compartment 514. In uncompressed position, top 560 of bellows 514 is Slightly separated above the upper legs 535. When a force is applied to the upper part 560, the body 515 of the bellows 514 is compressed and the upper part 560 enters contact with legs 535. Because legs 535 are fixed to a structure that can compress itself (the contact of dome 534), the additional application of a force against the part upper 560 causes leg 535 to move down. This does that the dome structure (contact 534) is compressed and that the circuit close. Then a signal is sent from commutation. Once the force stops applying or the force decreases, the top 560, as well as leg 535, move  out while the dome structure 534 expands.

Although the invention has been shown and described in specific way referring to the realizations preferred thereof, a person skilled in the art will understand that several changes can be made in its forms and details without depart from the scope of the invention.

Claims (11)

1. Switching element (82) that can be pressed for use in a handpiece surgical (30) to seal an interior of the handpiece (30), comprising the switching element (82):

a body (83) and a skirt (85) extending peripherally around the body (83) to allow the body (83) to sink easily when pressed and return to its original position upon release; Y

characterized by:

a Cape metal (110, 122) as a permeability barrier arranged in less a location of at least the body (83) or the skirt (85) to obtain a permeability barrier for the at least one Location.

2. Switching element (82), according claim 1, wherein the body (83) is in the form of rocker switch formed by an elastomer. 3. Switching element (82), according claim 1 or 2, wherein the layer (110, 122) is arranged only on a lower face (112) of the oriented skirt, in use, into the handpiece (30). 4. Switching element (82), according claim 1 or 2, wherein the layer (110, 122) is arranged on a lower face (112) of the body (83) and of the skirt (85). 5. Switching element (82), according claim 1 or 2, wherein the layer (110, 122) is formed in an intermediate part of at least the body (83) or the skirt (85) between upper and lower surfaces of the same. 6. Switching element (82), according any one of the preceding claims, wherein the peripheral skirt (85) has a thickness less than the thickness of the body (83), the layer (110, 122) being formed on at least one face bottom (112) of the skirt (85). 7. Switching element (82), according claim 7, wherein the metal layer (110, 122) is a metal coating having a thickness of between approximately 0.127 µm (5 µm) and about 127 µm (0.005 inches). 8. Switching element (82), according any one of claims 1 to 6, wherein the layer (110, 122) is formed integrally with at least the body (83) or the skirt (85). 9. Switching element (82), according any one of claims 1 to 8, wherein the layer (110, 122) is separated from a lower face (112) of the body (83) and the skirt (85). 10. Switching element (82), according any one of claims 1 to 8, wherein the layer (110, 122) is arranged immediately adjacent to the minus the body (83) or the skirt (85). 11. Switching element (82), according any one of the preceding claims, wherein the skirt (210) has a series of folds (220) formed in the same.