JP2005158579A - Electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic equipment capable of protecting an electric circuit inside it from static electricity in a simple structure. <P>SOLUTION: By selectively press operating a plurality of operating keys 7 arranged on a panel of a front case 2, contact switching actions of a sheet-shaped switch main body 9 installed on a rear side of the panel are to be performed. On the surface of the sheet-shaped switch main body 9, carbon ink is printed to form a conductive layer 15, which 15 is to be connected to a bracket 5 as a grounding material arranged inside an equipment main body 1. With this, even if static electricity charged on an operator happens to get inside the front case 2 at operation of the operating keys 7, the static is grounded off from the conductive layer 15 formed on the surface of the sheet-shaped switch main body 9, so that electric circuits such as a control circuit fitted in the equipment main body 1 can be protected from the static. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electronic device that operates an internal switch by an operator operating an operation key arranged on a panel surface of the device body, and in particular, an electric circuit in the device body is detected from static electricity charged to the operator. The present invention relates to an electrostatic countermeasure structure for protection.

  In an electronic device such as an in-vehicle audio device or a navigation device, a plurality of operation knobs are arranged on the panel surface of the device body, and an operator rotates or presses each operation knob, so that it is placed on a circuit board in the device body. Since the mounted rotary encoder, push switch, etc. are operated to perform various controls, when the operator operates the operation knob, static electricity charged to the operator is generated from the gap around the operation knob. May get inside the device itself. In particular, when the operation knob is a push-type operation key that swings or moves up and down by an operator's pressing operation, a push switch that is operated by the operation key is disposed close to the back side of the panel surface together with the circuit board. For this reason, static electricity that has entered the device main body flows into the wiring pattern on the circuit board, and there is a risk of damaging an electric circuit such as a control circuit connected to the circuit board.

  Therefore, conventionally, a conductive plate is interposed between the panel surface of the device main body and the circuit board on which the push switch is mounted, and static electricity that has entered the device main body is grounded to the ground line via this conductive plate (grounding). ) To protect the electric circuit in the device body from static electricity (see, for example, Patent Document 1). This conductive plate is made of a metal plate such as stainless steel, and has a plurality of through holes formed by pressing. In addition, the conductive plate and the circuit board are fixed to the back side of the panel surface using a plurality of screws, and the push switch mounted on the circuit board passes through the through hole of the conductive plate and touches the back side of the operation key. It touches.

In the conventional electronic device schematically configured as described above, when an operator presses an arbitrary operation key arranged on the panel surface of the device body, the push switch on the circuit board is operated by the pressing force. Thus, a desired control operation assigned to the operation key is executed. In addition, even when static electricity charged to the operator enters the inside of the device main body through the gap around the operation key when the operation key is pressed, this static electricity is grounded to the ground line through the conductive plate. The electrical circuit in the device body is protected from static electricity.
Japanese Utility Model Publication No. 5-31198 (page 6-8, FIG. 2)

  In the above-described conventional technology, a conductive plate made of a metal plate is added to protect the electric circuit in the device body from static electricity, and a plurality of through holes through which the push switch is inserted are provided in advance in this conductive plate. Since it is necessary to press work, the cost of parts is greatly increased by taking countermeasures against static electricity. In addition, such a conductive plate is used on the back side of the panel surface of the main body of the device. Therefore, there is a problem in that the assembly process becomes complicated and the manufacturing cost of the electronic device increases.

  The present invention has been made in view of the actual situation of the prior art, and an object thereof is to provide an electronic device that can protect an electric circuit in the device main body from static electricity with a simple configuration.

  In the present invention, a sheet-like switch body operated by operation keys arranged on the panel surface of the device body is laid on the back side of the panel surface, and a conductive layer is formed on the surface of the sheet-like switch body by printing carbon ink. The conductive layer is connected to a ground member in the device main body. In this way, when carbon sheets are printed on the surface of the sheet-like switch body, which is originally required for electronic equipment, to take measures against static electricity, it is possible to protect the electric circuit from static electricity with a simple configuration without requiring additional parts. it can.

  In the electronic device of the present invention, a conductive layer is formed by printing carbon ink on the surface of the sheet-like switch body, and this sheet-like switch body is supported on a support plate and laid on the back side of the panel surface of the device body. Because the conductive layer is connected to the ground member in the device body, even if static electricity charged by the operator enters the device body through the gap around the operation key, this static electricity is printed on the surface of the sheet-like switch body. It is dropped from the formed conductive layer to the ground and does not flow into the electric circuit, and therefore, an electrostatic countermeasure can be achieved with a simple configuration without requiring additional parts.

  The present invention comprises an operation key disposed on the panel surface of the device body, a sheet-like switch body laid on the back side of the panel surface, and a support plate for supporting the sheet-like switch body, In an electronic device in which the contact switching operation of the sheet-like switch body is performed by an operation, a conductive layer is formed by printing carbon ink on the surface of the sheet-like switch body, and this conductive layer is disposed inside the device body. It was set as the structure connected to the earth member made.

  According to the electronic device configured as described above, even if static electricity charged to the operator when the operation key is operated enters the inside of the device body, the static electricity is generated from the conductive layer printed on the surface of the sheet-like switch body. Since it is dropped to the ground, it is possible to prevent static electricity from flowing into the electric circuit in the apparatus main body, and thus it is possible to protect the electric circuit from static electricity with a simple configuration without requiring additional parts.

  In the above configuration, the sheet-like switch body includes a base film having a fixed contact on the surface, an overfilm laminated and integrated on the base film, and a fixed contact interposed between the base film and the overfilm. It is preferable that a conductive layer is formed by printing carbon ink on the surface of the over film. At that time, it is preferable to fold the protrusion integrally formed on the overfilm to the back surface of the support plate supporting the sheet-like switch body, and to connect the conductive layer printed on the protrusion to the ground member facing the support plate, If it does in this way, a conductive layer and a ground member can be connected easily and assembly workability will improve.

  Further, in the above configuration, the LED is mounted on the base film of the sheet-like switch body, and a through-hole through which the LED is inserted is formed in the uppermost film of the sheet-like switch body. It is preferable that the display unit can be illuminated. When such an illumination mechanism is employed, the LED light can be prevented from being irregularly reflected on the surface of the sheet-like switch body by the black carbon ink printed on the over film. It is possible to prevent leakage from an undesired part.

  The embodiment will be described with reference to the drawings. FIG. 1 is a front view of an in-vehicle electronic device, FIG. 2 is an enlarged sectional view taken along line II-II in FIG. 1, and FIG. 4 is a plan view of the support plate and the sheet-like switch body, FIG. 5 is a plan view of the holding substrate, FIG. 6 is a sectional view taken along line VI-VI in FIG. 5, and FIG. FIG. 8 is a plan view showing a state where the support plate and the sheet-like switch body are placed on the bracket, and FIG. 9 is a cross-sectional view of the main part of the sheet-like switch body.

  The in-vehicle electronic device according to the present embodiment is used as, for example, a navigation device, and is attached to a metal external chassis (not shown) disposed on an instrument panel or the like in a vehicle and a front end portion of the external chassis. And a panel unit 1 which is a device body. The panel unit 1 includes a front case 2 and a rear case 3 made of synthetic resin, and both cases 2 and 3 are joined and integrated by snap coupling.

  As shown in FIG. 1, a rectangular opening 2a is formed at the center of the front surface (panel surface) of the front case 2, and a liquid crystal display (LCD) 4 arranged inside the panel unit 1 has an opening 2a. It is exposed inside. In addition, a pair of rotary knobs 6 and a plurality of operation keys 7 are arranged on the front surface of the front case 2, and these rotary knobs 6 and the operation keys 7 are arranged close to the periphery except for the upper side of the opening 2a. . The rotary knob 6 and the operation key 7 are formed of a hard plastic such as ABS resin and are not shown in the figure. However, a display portion representing its function and the like is formed on the surface of the rotary knob 6 and the operation key 7. Yes. The rotary knob 6 is for rotating a rotary operation type electric component to be described later. As shown in FIG. 2, the rotary knob 6 protrudes from the front surface of the front case 2 which is a panel surface by a predetermined dimension H. The protrusion amount H of the rotary knob 6 is set to a relatively large value in consideration of operability. In the present embodiment, the protrusion amount H is set to about 10 mm and the operator rotates the rotary knob 6. It is easy to do.

  On the other hand, the operation key 7 is used to press a push switch, which will be described later, and this operation key 7 is supported by a beam-like member 7a attached to the back surface of the front case 2 through a hinge portion 7b so as to be swingable. Yes. As shown in FIG. 3, the operation key 7 slightly protrudes to the front side through the through hole 2 b of the front case 2, so that the operator can easily press the top surface of the operation key 7. In the case of the present embodiment, a plurality of operation keys 7 arranged close to each other in rows on the left and right sides of the front case 2 are hinged to a common bar-like member 7a and unitized, but they are separated from each other. Individual operation keys 7 may be used. The operation key 7 moves in the through hole 2b with the hinge portion 7b as a swing fulcrum. The operation key swings in a seesaw shape in the through hole 2b around the rotation axis, or the front and rear direction in the through hole 2b. It is also possible to use an operation key that moves in parallel, and it is only necessary that the operation key 7 can operate a push switch described later by a pressing operation of the operator.

  A bracket 5 made of a conductive metal plate is screwed to the inner bottom surface of the rear case 3, and the liquid crystal display 4 is attached to the bracket 5 by means such as screwing or riveting. The bracket 5 functions as an earth member and is maintained at the same potential as the ground on the vehicle body side. As shown in FIGS. 3 and 8, mounting portions 5a bent in an L-shape are integrally formed on both left and right sides of the bracket 5, and a frame-like support plate 8 is formed on the mounting portions 5a. It is fixed by means such as screwing. The support plate 8 is formed by pressing a metal flat plate such as an iron plate, and sheet-like switch bodies 9 are laid on the left and right sides and the lower side except the upper side.

  As shown in FIG. 4, a pair of through-holes 8a are formed in the upper corners of the support plate 8, and a pair of through-holes 9a matching the through-holes 8a are formed in the sheet-like switch body 9. Yes. As shown in FIG. 9, the sheet-like switch body 9 is composed of a base film 11 and an over film 12 laminated and integrated via a plurality of tact springs 10, and the base film 11 and the over film 12 are It is formed of a flexible film such as PET. A plurality of LEDs 13 are mounted on the surface of the base film 11, and a plurality of fixed contacts 14 and a wiring pattern (not shown) are formed. The display portion of the rotary knob 6 and the operation key 7 described above is emitted from each LED 13. Illuminated by the light emitted. In addition, a base plate portion 11b is formed on both the left and right sides of the base film 11 via narrow lead portions 11a, and a sheet-like switch body 9 is provided on the lower side of the base film 11 as a control circuit (not shown). A connector portion 11c for connection is extended and formed. The back surface of the base film 11 is bonded to the support plate 8 with an adhesive substantially all over the lead portion 11a, the substrate portion 11b, and the connector portion 11c.

  The tact spring 10 is formed by forming a conductive metal thin plate such as phosphor bronze into a dome shape, and this tact spring 10 is disposed behind the pressing protrusions 7c formed on the inner surface of each operation key 7 (FIG. 3). The top of the tact spring 10 faces the fixed contact 14 directly below it with a predetermined distance, and a pair of the tact spring 10 and the fixed contact 14 constitutes one push switch. That is, the tact spring 10 functions as a movable contact of the push switch, and the sheet-like switch body 9 has a plurality of push switches corresponding to the operation keys 7.

  The over film 12 is attached to the portion of the base film 11 excluding the lead portion 11a, the substrate portion 11b, and the connector portion 11c, and each tact spring 10 is prevented from falling off the base film 11 by the over film 12. A plurality of through-holes 12 a are formed in the over film 12, and each LED 13 is inserted through the through-hole 12 a and faces the rotary knob 6 and the back side of the operation key 7. Further, the base film 11 and the over film 12 have holes having the same shape. The over-film 12 is attached to the base film 11 and the both holes are overlapped, so that the sheet-like switch body 9 has been described above. A through hole 9a is formed. Further, a plurality of projecting pieces 12b projecting outward from the edge of the base film 11 are integrally formed on the left and right sides of the over film 12, and a conductive layer is formed on the surface of the over film 12 including these projecting pieces 12b. 15 is formed. The conductive layer 15 is formed by printing carbon ink on the surface of the over film 12. As shown by hatching in FIG. 4, the conductive layer 15 is a part of a portion such as a portion overlapping the top of each tact spring 10. The over film 12 is printed on almost the entire surface except for the above. Here, the conductive layer 15 can be formed on the surface of the overfilm 12 after completion as the sheet-like switch body 9, but the carbon on the surface of the sheet-like overfilm 12 before being attached to the base film 11. After the ink is printed and the conductive layer 15 is formed, if the overfilm 12 is cut out and attached to the base film 11, the conductive layer 15 can be easily formed on the production line of the sheet-like switch body 9. it can.

  In FIG. 4, the lower side portion of the sheet-like switch body 9 protruding outward from the edge portion of the support plate 8 and the protruding pieces 12 b of the over film 12 are folded inward and adhered to the back surface of the support plate 8. These folded portions are in contact with the mounting portion 5a of the bracket 5 (see FIG. 9). As a result, the conductive layer 15 formed on the surface of the sheet-like switch body 9 is connected to the bracket 5 that is a ground member via the folded portion of each protrusion 12b and the like.

  As shown in FIGS. 2, 7, and 8, a stud 16 as a mounting portion is caulked and fixed to the back side of the support plate 8, and the stud 16 is 180 degrees across the through holes 8 a on both the left and right sides. It is arrange | positioned in the opposing position. These studs 16 hang down toward the inner bottom surface of the rear case 3, and a large number of small holes 3 a for partially reducing the mechanical strength are formed in the portion of the rear case 3. A holding board 17 is fixed to the rear ends of the pair of studs 16 using screws 18, and a rotary encoder 19 that is a rotary operation type electric component is mounted on the holding board 17. A rotary shaft 19a of the rotary encoder 19 is inserted through the support plate 8 and the through holes 8a, 9a of the sheet-like switch body 9, and protrudes forward of the front case 2. The rotary knob 6 is press-fitted to the rotary shaft 19a. It is fixed. The rotary knob 6 has a cylindrical peripheral surface portion 6a, and the rear end of the peripheral surface portion 6a enters an annular groove 2c formed on the front surface of the front case 2 (see FIG. 2). However, a predetermined gap h is secured between the rear end of the peripheral surface portion 6a and the inner bottom surface of the annular groove 2c. In the present embodiment, this gap h is set to about 1.5 mm. . In addition, although LED13 for illuminating the display part of the rotary knob 6 is arrange | positioned inside the annular groove 2c, when the rear end of the peripheral surface part 6a of the rotary knob 6 enters in the annular groove 2c, Since the jetty 2d at the inner peripheral edge of the annular groove 2c partially overlaps the rear end of the peripheral surface portion 6a, the light of the LED 13 does not leak outside the front case 2 through the annular groove 2c. .

  As shown in FIGS. 5 and 6, the holding substrate 17 is composed of the substrate portion 11 b of the base film 11 described above and a reinforcing plate 20 that supports the substrate portion 11 b, and the substrate portion 11 b is composed of the reinforcing plate 20. It is attached to the entire back surface of the adhesive using an adhesive. The reinforcing plate 20 is made of a plastic plate such as glass-filled epoxy resin, and a pair of ear pieces 20a are formed by cutting out the outer edge portion thereof. These ear pieces 20 a are formed with attachment holes 20 b for inserting screws 18, and the holding substrate 17 is configured such that both ear pieces 20 a are attached to the rear ends of the studs 16 using the screws 18. These ear pieces 20a function as weak parts, and a plurality of terminal insertion holes 20c are formed in a region sandwiched between both ear pieces 20a of the reinforcing plate 20. The reinforcing plate 20 is obtained by extracting a plastic plate having a uniform thickness into a predetermined shape, and at the time of removing the outer shape, an ear piece 20a, a mounting hole 20b, and a terminal insertion hole 20c can be formed simultaneously. The substrate portion 11b is obtained by extending a base film 11 formed of a flexible film such as PET, and a solder land and a wiring pattern (not shown) are formed on the surface thereof. The substrate portion 11b is attached to almost the whole area except for both ear pieces 20a on the back surface of the reinforcing plate 20, and most of the holding substrate 17 excluding both ear pieces 20a is a two-layered structure including the reinforcing plate 20 and the substrate portion 11b. It has a structure. Therefore, the binaural piece 20a functioning as the fragile portion has a single-layer structure composed of only a plastic plate, and has a lower breaking strength than the other two-layer structure.

  The rotary encoder 19 outputs a pulse signal by rotating the rotary shaft 19a. In this embodiment, the rotary encoder 19 with a push switch that performs switching by pressing the rotary shaft 19a is used. Yes. The rotary encoder 19 is mounted on the central portion of the reinforcing plate 20, and a plurality of external terminals 19b projecting rearward from the rotary encoder 19 are inserted through the terminal insertion holes 20c of the reinforcing plate 20 to form solder lands on the board portion 11b. It is soldered to. As described above, since the holding substrate 17 on which the rotary encoder 19 is mounted has a two-layer structure of the reinforcing plate 20 and the substrate portion 11b, the rotary encoder 19 is mounted on the holding substrate 17 in a stable posture. Can do. As described above, since the base film 11 having the substrate portion 11b is a part of the sheet-like switch body 9, the rotary encoder 19 is mounted on the holding substrate 17 as shown in FIG. The sheet-like switch body 9 can be laid on the support plate 8. Then, the lead portion 11a of the base film 11 adhered on the support plate 8 is folded back to the back side of the support plate 8, and the rotary shaft 19a of the rotary encoder 19 is connected to the support plate 8 and the through holes 8a of the sheet-like switch body 9. After 9a is inserted and protruded forward of the front case 2, both ear pieces 20a of the reinforcing plate 20 are attached to the rear ends of the studs 16 using screws 18 as shown in FIG. The rotary encoder 19 mounted above can be attached to the support plate 8 via the stud 16.

  In the in-vehicle electronic device configured as described above, when the operator picks and rotates the peripheral surface portion 6 a of the rotary knob 6 protruding from the front surface of the front case 2, the rotary shaft of the rotary encoder 19 is linked to the rotary knob 6. The rotary encoder 19 outputs a pulse signal corresponding to the rotation direction and the rotation amount of the rotary knob 6. This output signal is input to a control circuit (not shown) through a wiring pattern formed on the base film 11 such as the substrate portion 11b of the holding substrate 17, and the control circuit executes, for example, volume adjustment based on the input signal. . In this case, since the rotary knob 6 protrudes from the front surface of the front case 2 with a relatively large dimension H (H≈10 mm), it is easy for the operator to pick up the peripheral surface portion 6a of the rotary knob 6, and the operability of the rotary knob 6 is improved. Has been increased. Further, since a gap h (h≈1.5 mm) is secured between the rear end of the peripheral surface portion 6a of the rotary knob 6 and the inner bottom surface of the annular groove 2c of the front case 2, as in this embodiment. Even if the rotary encoder 19 with a push switch is used, the push switch of the rotary encoder 19 can be operated by pressing the rotary knob 6 and pushing the rotary shaft 19a by a small amount. For example, the power of the navigation device can be turned on or off based on the contact switching signal.

  On the other hand, when the operator presses the top surface of an arbitrary operation key 7 exposed on the front surface of the front case 2, the operation key 7 is pushed into the through hole 2b with the hinge portion 7b as a swing fulcrum. The push switch of the sheet-like switch body 9 located immediately behind is operated. That is, when the top surface of an arbitrary operation key 7 is pressed, the pressing protrusion 7c formed on the inner surface of the operation key 7 presses the tact spring 10 of the sheet-like switch body 9, and the tact spring 10 is It buckles and contacts the fixed contact 14 just behind it. At this time, since a tactile feeling (moderation feeling) is generated from the tact spring 10, an operator who presses the operation key 7 can recognize that the push switch has been operated with a feeling of clicking. Further, even when static electricity charged to the operator enters the inside of the front case 2 through the gap between the operation key 7 and the through hole 2b when the operation key 7 is pressed, the static electricity is not generated in the sheet-like switch body 9. Since it is dropped from the conductive layer 15 formed on the surface to the ground line via the bracket 5 which is a ground member, an electric circuit such as a control circuit provided in the panel unit 1 can be protected from static electricity. In addition, since the conductive layer 15 is formed by printing black carbon ink, the conductive layer 15 suppresses irregular reflection of the light of the LED 13 on the surface of the sheet-like switch body 9, and therefore The light of the LED 13 can be prevented from leaking from an undesired part other than the display part of the operation key 7.

  Further, in the in-vehicle electronic device configured as described above, when a pressing force of a predetermined value or more is applied to the top surface of the rotary knob 6 due to an automobile collision or a sudden brake, the pressing force to the rotary knob 6 is changed to the rotary encoder 19. By concentrating on the both ear pieces 20a (fragile portion) of the holding substrate 17 through the holding substrate 17, the holding substrate 17 breaks at the base end portion of both ear pieces 20a and is separated from the stud 16. As a result, since the rotary knob 6 is pushed into the annular concave groove 2c of the front case 2 by the maximum gap h, the amount of protrusion of the rotary knob 6 from the front case 2 is reduced. In this embodiment, H− It decreases to h = 8.5 mm. Therefore, the amount of protrusion of the rotary knob 6 from the panel surface of the front case 2 is greatly reduced as compared with the normal use, and the safety at the time of automobile collision or sudden braking is sufficiently ensured.

  Thus, in the vehicle-mounted electronic device according to the present embodiment, a sheet-like shape laid on the back side of the panel surface by selectively pressing the plurality of operation keys 7 disposed on the panel surface of the front case 2. A contact switching operation of the switch body 9 is performed, and a carbon ink is printed on the surface of the sheet-like switch body 9 to form a conductive layer 15, and the conductive layer 15 is disposed inside the device body 1. Even if the static electricity charged to the operator during operation of the operation key 7 enters the inside of the front case 2 through the gap between the operation key 7 and the through hole 2b. By dropping this static electricity from the conductive layer 15 formed on the surface of the sheet-like switch body 9 to the ground, an electrical circuit such as a control circuit provided in the device body 1 is protected from the static electricity. Door can be. Therefore, there is no need to dispose a conductive plate exclusively for static electricity countermeasures on the back side of the front case 2, and an electric circuit can be protected from static electricity with a simple configuration without requiring additional parts.

  The sheet-like switch body 9 includes a base film 11 having a fixed contact 14 and a wiring pattern on the surface, an overfilm 12 laminated and integrated on the base film 11, and the base film 11 and the overfilm. 12 and a dome-shaped tact spring 10 interposed between them, and a pair of tact spring 10 and fixed contact 14 constitute one push switch, and carbon ink is printed on the surface of the over film 12 Thus, since the conductive layer 15 is formed, the conductive layer 15 can be easily formed on the production line of the sheet-like switch body 9. Then, the protrusion 12b integrally formed on the over film 12 is folded back on the back surface of the support plate 8 that supports the sheet-like switch body 9, and the support layer 8 is placed with the conductive layer 15 printed on the protrusion 12b. Since it is connected to the bracket 5, the conductive layer 15 on the surface of the sheet-like switch body 9 can be easily connected to the bracket 5 that is a ground member, and the assembling workability is improved.

  Further, the LED 13 is mounted on the base film 11 of the sheet-like switch body 9, and a through hole 12 a through which the LED 13 is inserted is formed in the over film 12, and the display of the operation key 7 is illuminated by the light of the LED 13. Since the mechanism is adopted, it is possible to suppress the diffuse reflection of the light of the LED 13 on the surface of the sheet-like switch body 9 by the conductive layer 15 made of black carbon ink printed on the over film 12. It is possible to prevent leakage from an undesired part other than the display unit.

  In the above embodiment, the case where the sheet-like switch body 9 with a click feeling in which the base film 11 and the over film 12 are laminated and integrated via the tact spring 10 has been described, but the lower part is interposed via the spacer film. It is also possible to use a non-click type sheet-like switch body called a membrane switch in which a film and an upper film are laminated and integrated. In this case, a conductive layer may be formed by printing carbon ink on the surface of the upper film, and if a dedicated click member is interposed between the upper film of the sheet-like switch body and the operation key, the click feeling is obtained. It can also be granted.

It is a front view of the vehicle-mounted electronic device which concerns on an Example. It is an expanded sectional view which follows the II-II line of FIG. It is an expanded sectional view which follows the III-III line of FIG. It is a top view of a support plate and a sheet-like switch main body. It is a top view of a holding substrate. It is sectional drawing which follows the VI-VI line of FIG. It is a disassembled perspective view which shows the attachment structure of a holding substrate. It is a front view which shows the state which mounted the support plate and the sheet-like switch main body in the bracket. It is principal part sectional drawing of a sheet-like switch main body.

Explanation of symbols

1 Panel unit (equipment main unit)
2 Front case 2a Opening 2b Through hole 3 Rear case 4 Liquid crystal display 5 Bracket (grounding member)
5a Placement part 6 Rotating knob 7 Operation key 7a Cross-shaped member 7b Hinge part 7c Pressing protrusion 8 Support plate 9 Sheet-like switch body 10 Tact spring 11 Base film 12 Over film 12a Through hole 12b Protruding piece 13 LED
14 Fixed contact 15 Conductive layer

Claims (4)

An operation key disposed on the panel surface of the device main body, a sheet-like switch body laid on the back side of the panel surface, and a support plate for supporting the sheet-like switch body, and the sheet by the operation of the operation key In the electronic device where the contact switching operation of the switch body is performed,
An electronic apparatus comprising: a carbon ink printed on a surface of the sheet-like switch body to form a conductive layer; and the conductive layer is connected to a ground member disposed inside the apparatus main body.   2. The sheet-like switch body according to claim 1, wherein the sheet-like switch body is provided with a base film having a fixed contact on the surface thereof, an overfilm laminated and integrated on the base film, and interposed between the base film and the overfilm. An electronic device comprising: a dome-shaped tact spring that can contact and separate from the fixed contact; and the conductive layer is printed on a surface of the over film.   3. The conductive layer printed on a surface of the projecting piece is connected to the ground member by integrally forming the projecting piece on the over film and folding the projecting piece on the back surface of the support plate. Electronic equipment characterized by having been made. 4. The LED according to claim 2, wherein an LED is mounted on the base film, a through-hole through which the LED is inserted is formed in the over film, and the display portion of the operation key can be illuminated by the light of the LED. Electronic equipment characterized by that.

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