Autoclavable medical device and operating device for an autoclavable medical device

Abstract

Autoclavable device comprising a metal housing (10), wherein the housing (10) comprises at least one electrical conductor embedded in an inorganic fixing material (120), which forms an electrical feedthrough (100) with the fixing material (120), extending from an inner side of the housing (10) at least through a section of the fixing material (120), wherein the fixing material (120) is arranged in a metal ring (110) which is inserted into an opening (11) of the housing (10), wherein the metal ring (110) has a higher coefficient of thermal expansion α than the fixing material (120), so that the electrical feedthrough is designed as a pressure glass feedthrough, and wherein the electrical feedthrough (100) is part of a sensor of an actuating device for electronic components within the housing (10).

Description

Field of invention

[0001] The invention relates to an autoclavable device, in particular a medical device, comprising electronic components. The device specifically includes an electric motor and / or a turbine, in particular a compressed air turbine, and / or an electric lighting device. The invention further relates to an actuating device for an autoclavable device. Background of the invention

[0002] In practice, medical devices are often sterilized by autoclaving. For this purpose, the medical device or parts thereof are placed in an autoclave to be sterilized with steam at a high temperature (typically 134 °C) and increased pressure (typically 2 bar).

[0003] Autoclaving is highly efficient against germs and enables safe sterilization even of hidden areas of the medical device, i.e. areas that are not accessible by hand.

[0004] When autoclaving, it is important that the steam can reach all surfaces of the medical device.

[0005] Providing electrically operated medical devices that are autoclavable as a whole is a complex undertaking, especially those that include electronics.

[0006] In practice, it is only possible to make a part of the medical device autoclavable, particularly a part that does not contain electrical or electronic components. However, this requires disassembling the medical device, and by its very nature, it can only be partially sterilized by autoclaving.

[0007] In contrast, it makes sense to design the electrical and electronic components of a medical device to be autoclavable. This applies in particular to the operating mechanism, especially the switch for turning the medical device on and off.

[0008] In this regard, consideration is given to sealing the housing of the medical device in such a way that electrical and / or electronic assemblies are located within a hermetically sealed, autoclavable housing.

[0009] The problem, however, is to design the housing in such a way that it can withstand a large number of autoclaving cycles, despite the accessibility of an operating device.

[0010] Even small amounts of water vapor entering the device can lead to malfunctions or failure of the electronics. To prevent condensation, the water content inside the housing must remain below the dew point threshold throughout the device's entire lifespan. This threshold is typically a maximum water content of 5000 ppm in the enclosed gas atmosphere.

[0011] Seals, particularly polymer seals such as O-rings, are well-known in the watchmaking industry and allow watch cases to withstand high pressures underwater. Nevertheless, such watches may still be equipped with user-accessible switches or dials. However, the polymer seals used are generally at least partially gas-permeable, meaning that water vapor penetrates them during every autoclave cycle.

[0012] If the water concentration inside the housing rises to such an extent that the dew point is reached, malfunctions or damage can occur.

[0013] As a rule, polymer seals can therefore only withstand a few hundred autoclave cycles before the medical device needs to be overhauled or replaced.

[0014] Capacitive sensor surfaces made of glass are also well-known, particularly in displays such as smartphones. Touching the display causes a local change in the capacitance of an electronic component, allowing the position of the finger on the display to be determined. Control elements on glass-ceramic cooktops are based on a similar principle, namely that of a capacitive switch.

[0015] However, the housing materials used in medical technology, especially austenitic stainless steel, are difficult to equip with glass or glass-ceramic discs, as these have a significantly different coefficient of thermal expansion.

[0016] Glass panels commonly used in housings, behind which, for example, a commercially available capacitive proximity switch might be located, are generally not sufficiently gas-tight to withstand a large number of autoclave cycles. In particular, the glass panels are bonded to the housing using polymeric adhesives. Object of the invention

[0017] In contrast, the invention is based on the objective of providing an autoclavable device with an actuating device which is designed for a high number of autoclaving cycles, in particular for more than 500 autoclaving cycles. Summary of the invention

[0018] The object of the invention is already solved by an autoclavable device and by an actuating device for an autoclavable device according to one of the independent claims.

[0019] Preferred embodiments and further developments of the invention can be found in the subject matter of the dependent claims, the description and the drawings.

[0020] The invention relates to an autoclavable device. In particular, the invention relates to a medical device.

[0021] The invention relates in particular to an autoclavable device comprising an electric motor, a turbine, and / or a device for emitting electromagnetic radiation, especially a light source. For example, the invention relates to a medical drill, in particular a dental drill, a saw, or a file. Furthermore, the invention may also relate to a lighting device, in particular a medical one, for example, a diagnostic and / or surgical light, a dental curing device, and / or a device for generating and / or evaluating fluorescence. The invention may also relate to an electrosurgical device, in particular a medical device for electrocoagulation or a laser scalpel.

[0022] For the purposes of this invention, an autoclavable device also includes that part of a device which is autoclavable as a whole. This may, in particular, be the handpiece of a device with an actuating mechanism.

[0023] The housing of the autoclavable device consists at least partially of metal and is at least partially hermetically sealed, so that electrical and / or electronic components may be arranged in the housing.

[0024] According to the invention, the housing comprises an electrical conductor embedded in an inorganic fixing material. In particular, the electrical conductor is fused into the fixing material. The fixing material is, in particular, an electrically insulating fixing material, e.g., glass, glass-ceramic, and / or ceramic. Combinations thereof are also possible, as are multilayer structures of different fixing materials.

[0025] The electrical conductor forms an electrical feedthrough with the fixing material, which extends from an inside of the housing at least through a section of the fixing material.

[0026] An electrical feedthrough within the meaning of the invention is understood to be an electrical conductor, preferably made of metal, in particular a pin, which is guided, in particular in a glazing unit, at least partially through an opening in the metal housing.

[0027] The electrical conductor, together with the fixing material, forms the electrical feedthrough, with the fixing material serving as an insulator against the adjacent metal housing and at the same time as a hermetic seal.

[0028] A glass and / or glass-ceramic is preferably used as the fixing material. In particular, a glass or glass-ceramic that can be melted between 800 and 1200 °C can be used.

[0029] According to the invention, the electrical feedthrough is a component of a sensor of an actuating device.

[0030] An actuating device within the meaning of the invention is understood to be an element that can be operated manually by the user, possibly also with the aid of a handling device such as a stylus, and with which a function of the device can be set and / or controlled. A sensor is provided for this purpose, which can detect actuation by the user.

[0031] The operating device serves to call up and / or set the device's operating states. In particular, the operating device forms the interface between the device and the user. Operating states include, for example, switching the device on and / or off, or its various functions. Of course, other operating states are also possible, such as setting a light intensity, motor speed, turbine speed, etc.

[0032] In the simplest case, the sensor is designed as a switch to turn the device on and off.

[0033] The electrical feedthrough forms, as will be explained below by way of example, at least one component of the sensor of the actuating device.

[0034] In particular, the device can be part of an electrical circuit that can be closed, thus forming a switch.

[0035] The capacitor can also be part of an electronic circuit for switching on and / or controlling functions of the autoclavable device. For example, a metal pin embedded in an inorganic fixing material already constitutes a cylindrical capacitor due to the different dielectric constants of the inorganic material and the metal pin.

[0036] According to a first embodiment of the invention, the electrical conductor extends only through a section of the inorganic fixing material and is spaced away from an outer surface of the fixing material.

[0037] In this embodiment, the electrical conductor terminates within the fixing material, viewed from the inside of the housing. The fixing material effectively covers the conductor on the outside of the housing, thereby further improving the seal and potentially reducing the risk of short circuits. Furthermore, eliminating the material interface between the conductor and the fixing material reduces the risk of microbial adhesion. This technical solution also provides greater design freedom for the device's designers and / or improves user experience.

[0038] In another embodiment of the invention, the electrical connection extends to a top surface of the inorganic fixing material, in particular to an outer surface of the housing. This, too, may be desirable for user guidance purposes.

[0039] A feedthrough designed in this way can also be part of an actuating device that generates a switching operation by closing an electrical circuit. For example, the electrical feedthrough can form a switch together with the housing and / or with another electrical feedthrough.

[0040] A switching operation can be carried out, for example, by the switch including a contact element made of electrically conductive material, which closes the switch when actuated.

[0041] The contact element can be designed in particular as a rocker or as a dome arranged above the feedthrough.

[0042] The sensor is thus designed as a switch. Current for operating the device can flow directly through the sensor, which is configured as a switch. In this embodiment of the invention, an evaluation circuit is not required.

[0043] It is also possible to illuminate the fixing material from the rear, i.e., from the inside of the housing. In particular, the illumination pattern can depend on the operating state. When the device is switched off, the illumination can, in effect, highlight the switch and / or sensor. Similarly, a change in the illumination pattern, for example, through a change in brightness and / or color, can indicate the device's response to user interaction. This illumination is made possible by the hermetically sealing feedthrough of the housing. The necessary light sources, such as LEDs and / or OLEDs, and the associated control electronics can be integrated into the housing interior and are therefore autoclavable along with the entire device.

[0044] According to one embodiment of the invention, the dome is gas-tight sealed, in particular made of metal, and is gas-tightly connected to the housing or to a component connected to the housing.

[0045] This prevents water vapor from entering during autoclaving.

[0046] In another embodiment, the dome is provided with at least one opening for the entry of water vapor, such that the interior of the dome can also be reached by water vapor during autoclaving.

[0047] Instead of an electrically conductive contact element that is actuated by the user to close the circuit, another embodiment of the invention provides that a circuit can be closed solely by the user's hand or finger. In this embodiment, current can flow through the user's finger or hand to trigger a switching operation. A separate contact element is not provided in this embodiment of the invention. This embodiment has the advantage that an external contact element for closing the circuit can be dispensed with. However, the current for operating the device cannot flow through the sensor.

[0048] In another embodiment of the invention, the electrical feedthrough is part of an electronic circuit which is designed as an actuating device due to a change in inductance or capacitance.

[0049] The sensor is designed in particular as a proximity switch which, when approached, for example by the hand or finger of the user, triggers a signal change, in particular a switching signal.

[0050] Preferably, the sensor is designed as a capacitive proximity switch. The capacitor formed by the feedthrough is preferably part of the capacitive proximity switch.

[0051] Such a capacitive proximity switch is designed in particular as an oscillation circuit, the frequency of which changes when approaching, which in turn is detected by an electronic circuit and converted into a switching signal.

[0052] Due to the different dielectric constant of the user's finger or hand, or any other handling device, the capacitance of the capacitor formed by the electrical connection changes. This, in turn, results in a frequency change, which is detected by the electronic circuit. Such electronic circuits, especially those whose sensitivity automatically adjusts to changing environmental conditions, are known to those skilled in the art.

[0053] Preferably, the capacitor formed by the feedthrough constitutes the capacitance of the oscillator circuit, so that, as is provided in a preferred embodiment of the invention, a further capacitor within the oscillator circuit can be dispensed with.

[0054] In a further development of the invention, the fixing material, together with the electrical conductor (i.e., the electrical feedthrough), is arranged in a metal ring, which in turn is inserted into an opening in the housing of the autoclavable device. The electrical conductor is fused into the metal ring along with the fixing material.

[0055] The actuating device can thus be provided as a modular component that simply needs to be inserted into the housing. Therefore, the glazing of the feedthrough does not need to take place at the point of housing assembly.

[0056] The metal ring can be welded or soldered to the metal housing. Preferably, a metal ring is used which has a coefficient of thermal expansion α (unless otherwise specified, always at 20 °C) that differs from that of the material of the adjacent housing by less than 3 ppm / K, preferably less than 1 ppm / K.

[0057] The metal ring is made in particular of titanium or stainless steel, especially austenitic stainless steel. Preferably, the metal ring is made of the same material as the housing.

[0058] It is understood that, in the context of the invention, the metal ring does not necessarily have to be circular, but can be designed in any shape, including angular shapes.

[0059] In one embodiment of the invention, the metal ring has a higher coefficient of thermal expansion than the fixing material, such that the feedthrough is designed as a pressure-fit glass feedthrough. Due to the higher thermal expansion of the metal ring compared to the glass, the latter is subjected to compressive stress during cooling. In particular, the metal ring can be made of a material whose coefficient of thermal expansion is at least 5, preferably at least 8 ppm / K higher than the coefficient of thermal expansion of the fixing material.

[0060] According to another embodiment of the invention, it is provided that the coefficients of expansion of the metal ring, the inorganic fixing material and / or the electrical conductor are adapted to each other.

[0061] For example, a metal ring can be used whose coefficient of thermal expansion α differs from that of the fixing material by less than 5, preferably less than 3 ppm / K.

[0062] In this embodiment of the invention, a material with a coefficient of thermal expansion α < 12 ppm / K is preferably used for the metal ring. In particular, titanium or a titanium alloy can be used.

[0063] In a further development of the invention, the autoclavable device comprises an actuating device with a plurality of electrical feedthroughs. This allows, in particular, the activation of various functions or the control of a function, such as a rotational speed.

[0064] The actuating device can be designed in such a way that it determines a position on a surface of the actuating device. This can be achieved, for example, by at least one through-hole that extends at least partially parallel to a surface of the device.

[0065] Furthermore, the position of a handling device, such as a finger, can be determined via a large number of electrical feedthroughs.

[0066] The actuating device can be designed in such a way that a plurality of different operating states of the autoclavable device can be set via a direction and / or the distance of an actuating movement.

[0067] For example, with multiple feedthroughs, a function can be controlled depending on whether they are traversed sequentially by a movement from the right or left. Furthermore, the distance of a handling device, such as a finger, can also control an operating state, such as the speed of a drill.

[0068] The inventors have discovered that by means of a feedthrough with an inorganic fixing material, an actuating device can be provided on an outside of the device in a very simple way, which makes it possible to sterilize the device together with the actuating device in an autoclave, whereby it can withstand a high number of autoclaving cycles.

[0069] The invention further relates to an actuating device for the autoclavable device described above. The actuating device is, in particular, designed as a switch.

[0070] The actuating device therefore comprises an electrical feedthrough consisting of an electrical conductor embedded in a fixing material.

[0071] Preferably, the actuating device comprises a metal ring which can be inserted into the opening of the housing of an autoclavable medical device. Brief description of the drawings

[0072] The subject matter of the invention will below be described with reference to schematically illustrated embodiments shown in the drawings. Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10, Fig. 11 to Fig. 12 will be explained in more detail. Fig. Figure 1 shows, schematically, the housing of a medical device which is to be provided with an actuating device according to the invention. Fig. 2 and Fig. Figure 3 shows two different embodiments of a usable actuating device. Referring to Fig. 4, Fig. 5, Fig. 6 to Fig. Section 7 will explain in more detail the function of a single electrical bushing used as an actuating device, which forms a capacitive proximity sensor, in various operating states. Fig. Figure 8 shows an embodiment with several feedthroughs arranged side by side and the resulting signal waveform when sweeping over the feedthroughs. Fig. Figure 9 shows the signal progression when swiping from different directions. Fig. Figure 10 shows an alternative embodiment of an actuating device with a plurality of electrical conductors in a single feedthrough.

[0073] Referring to Fig. 11 and Fig. 12 An alternative embodiment of an actuating device is to be explained in which a circuit is closed by pressing a contact element. Detailed description of the drawings

[0074] Fig. Figure 1 shows, schematically, the housing 10 of an autoclavable medical device.

[0075] The housing 10 is made of metal, in particular stainless steel, such as an austenitic stainless steel, especially alloy 1.4404. The housing has an interior 13 in which, in particular, electrical and / or electronic components (not shown) can be arranged.

[0076] Furthermore, the housing 10 has an opening 11 for inserting an actuating device for the autoclavable medical device. The opening 11 can, in particular, be designed as a bore.

[0077] The wall thickness of the housing, at least in the area of ​​the opening, is preferably 0.3 to 5 mm, particularly preferably 0.8 to 2 mm.

[0078] Fig. Figure 2 shows a first embodiment of a feedthrough 100, which can serve as an actuating device.

[0079] The feedthrough 100 consists of a fixing material 120 made of glass, in which a pin 130 made of metal is embedded, which forms an electrical conductor.

[0080] The pin 130 preferably has a diameter of 0.2 to 3 mm. The fixing material 120 is preferably 0.5 to 5 mm high and / or has a diameter between 0.7 and 5 mm.

[0081] As provided in one embodiment of the invention, a lighting device (not shown) can be arranged inside the housing, through which light passes through the fixing material 120 to the outside. This allows, for example, an illuminated actuation device and / or an optical indication of an operating status of the medical device.

[0082] Fixing material 120 and pin 130 form a cylindrical capacitor in the area of ​​the feedthrough 100.

[0083] The feedthrough 100 is surrounded by a metal ring 110, which serves to guide the opening (11 in Fig. 1) to be used in the housing.

[0084] This metal ring 110 can be easily and gas-tightly connected to the housing, for example by soldering or welding, resulting in a hermetically sealed housing. Preferably, the metal ring 110 is therefore made of the same material as the adjacent housing.

[0085] In the embodiment according to Fig. 2. The pen 130 runs to the top of the fixing material 120.

[0086] According to the embodiment according to Fig. In contrast, 3 is the end face of the pin 130 spaced from the top 140, the fixing material 120, by a distance D.

[0087] In this embodiment of the invention, the pin 130 cannot therefore be electrically contacted from the outside. The actuating device according to the exemplary embodiment shown below Fig. Therefore, 3 cannot be designed as a switch that triggers a switching operation by closing an electrical circuit.

[0088] Rather, the sensor, which detects the electrical connection according to Fig. 3 includes, designed as a capacitive proximity sensor.

[0089] Referring to Fig. 4, Fig. 5, Fig. 6 to Fig. Section 7 describes an embodiment of an actuating device, which is designed as a capacitive proximity switch, in various operating states.

[0090] As in Fig. As can be seen in Figure 4, the metal ring 110 is now inserted into the housing 10.

[0091] The metal ring 110 is preferably welded or soldered to the wall of the housing 10 in the contact area 12 to form a gas-tight connection. The use of the metal ring 110 allows for easy installation, as its material can be matched to that of the housing 10.

[0092] The embodiment according to Fig. 4, Fig. 5, Fig. 6 to Fig. 7 corresponds to the embodiment according to Fig. 2, in which the pin 130 extends to the top of the fixing material 120.

[0093] The pin 130 extends from the inside 14 of the housing 10 through the fixing material. As described above, the electrical feedthrough 100 thus configured forms a capacitor.

[0094] The pin 130 is connected to an evaluation circuit 30, which includes an oscillator circuit in which the feedthrough 100 serves as a capacitor of an electrical resonant circuit.

[0095] In the representation according to Fig. Figure 4 shows the actuating device in the unactuated state. This can correspond to a switching state of "Off".

[0096] As in Fig. As shown in Figure 5, an actuating element, in particular a finger 20, can be placed on the feedthrough 100.

[0097] Due to the different dielectric constant of the finger 20 compared to air, the frequency of the oscillator circuit changes, which in turn can be detected by the evaluation circuit 30, so that the switching signal is now, for example, "On".

[0098] As in Fig. 6 and Fig. As shown in Figure 7, according to a further embodiment of the invention, the actuating device is also designed as a proximity sensor, via which a multitude of operating states, i.e. not only “On” and “Off”, can be set.

[0099] As in Fig. As shown in Figure 6, a signal is generated as soon as the finger 20 approaches the feedthrough 100, which corresponds, for example, to an average operating state, such as an average voltage, power output, rotational speed, etc.

[0100] As then in Fig. As shown in Figure 7, a maximum power output can be set when the finger 20 is completely placed on the device 100.

[0101] It goes without saying that this adjustment can be made continuously or in steps.

[0102] Fig. Figure 8 shows how a plurality of feedthroughs 100 are arranged side by side in a housing 10.

[0103] In this embodiment, each of the feedthroughs 100 is arranged with a metal ring 110 in a separate opening of the housing 10.

[0104] As shown below the feedthroughs 100, when the finger 20 is moved over the feedthroughs in fields A to C, in this embodiment from left to right, direction-related information can be detected due to time-shifted changes in capacitance. This allows switching stages or an almost continuous control to be implemented.

[0105] In Fig. Figure 9 illustrates the change in capacitance when the feedthroughs are crossed either from the right or from the left. Depending on the direction, a different signaling process occurs, so that, for example, depending on the direction in which the finger is moved across fields A to C of an actuating device, the power can be increased or decreased.

[0106] Fig. Figure 10 shows an alternative embodiment of the invention in which a plurality of pins 130 are arranged in a single through-hole 100 with the fixing material 120.

[0107] The fixing material is arranged in a ring 110, as in the previously described embodiment.

[0108] In this embodiment of the invention, it is particularly possible to arrange a large number, especially more than five, of electrical conductors in a single feedthrough in order to detect, in particular, the position and / or direction of the finger 20 when stroking over it.

[0109] Fig. 11 and Fig. Figure 12 shows, schematically, an alternative embodiment of the invention.

[0110] In this embodiment, the actuating device is designed as a switch which generates a switching signal by closing an electrical circuit.

[0111] In this embodiment, a contact element is applied to the metal ring 110, which in this embodiment is designed as a switching membrane in the form of a dome 200.

[0112] By pressing the dome 200, as in Fig. As shown in 12, a circuit is closed and a switching signal is generated.

[0113] In this embodiment of the invention, the dome 200 is designed as a metal membrane which is connected to the metal ring 110 by welding or soldering. This prevents the ingress of water vapor during autoclaving.

[0114] The invention made it possible to easily provide an autoclavable, in particular an autoclavable medical device, which has a hermetically sealed housing with electrical or electronic components and can withstand a large number of autoclaving cycles. Reference symbol list 10 cases 11 Opening 12 Contact area 13 Interior 14 Inside 20 fingers 30 Evaluation circuit 100 execution 110 metal ring 120 fixing material 130 pens 140 Top 200 contact elements

Claims

Autoclavable device comprising a metal housing (10), wherein the housing (10) comprises at least one electrical conductor embedded in an inorganic fixing material (120), which forms an electrical feedthrough (100) with the fixing material (120), extending from an inner side of the housing (10) at least through a section of the fixing material (120), wherein the fixing material (120) is arranged in a metal ring (110) which is inserted into an opening (11) of the housing (10), wherein the metal ring (110) has a higher coefficient of thermal expansion α than the fixing material (120), so that the electrical feedthrough is designed as a pressure glass feedthrough, and wherein the electrical feedthrough (100) is part of a sensor of an actuating device for electronic components within the housing (10). Autoclavable device according to claim 1, characterized in that the electrical conductor extends only through a section of the inorganic fixing material (120) and is spaced away from an outer surface of the fixing material (120). Autoclavable device according to claim 1, characterized in that the electrical feedthrough (100) extends to an outer surface of the housing (10). Autoclavable device according to one of the preceding claims, characterized in that the sensor is designed as a proximity switch. Autoclavable device according to one of the preceding claims, characterized in that the sensor is designed as a capacitive sensor. Autoclavable device according to claim 1 or 3, characterized in that the electrical feedthrough forms a switch with the housing (10) and / or with a further electrical feedthrough (100). Autoclavable device according to the preceding claim, characterized in that the switch comprises a contact element (200) made of electrically conductive material which closes the switch when actuated. Autoclavable device according to the preceding claim, characterized in that the contact element (200) is designed as a dome arranged above the feedthrough. Autoclavable device according to one of the preceding claims, characterized in that the device comprises a light source inside the housing, which is arranged such that it emits light through the fixing material (120) to the outside. Autoclavable device according to one of the preceding claims, characterized in that the metal ring (110) consists of a material whose coefficient of thermal expansion α differs from that of the material of the adjacent housing by less than 3 ppm / K. Autoclavable device according to one of the preceding claims, characterized in that the electrical conductor is designed as a pin (130). Autoclavable device according to one of the preceding claims, characterized in that the autoclavable device comprises an actuating device with a plurality of electrical feedthroughs (100). Autoclavable device according to one of the preceding claims, characterized in that the device is designed as an autoclavable medical device. Autoclavable device according to one of the preceding claims, characterized in that the inorganic fixing material (120) is glass and / or glass ceramic. Autoclavable device according to one of the preceding claims, characterized in that the autoclavable device is designed as a medical drill, saw or file, medical lighting device, dental hardening device, device for stimulating and / or evaluating fluorescence, or as an electrosurgical device.

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