JP2009170125A - Switch structure of electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the other switch from being erroneously inputted, even if a finger touches the keycap of the switch, when the keycap of either one of two adjacent switches is depressed. <P>SOLUTION: Three keyswitches (10, 20, and 30) are installed in a prescribed array direction inside an upper case 1 without providing a partition part between keycaps (11, 21, and 31) adjacent to each other. Each pair of fixed-contact patterns (13, 23, and 33) is separated from each other in the array direction and formed on a circuit board 4 symmetrically with respect to the center of the tip of the central part of each dome-shaped rubber spring (14, 24, and 34). The tip of the central part of each dome-shaped rubber spring (14, 24, and 34) is provided with each movable contact (12, 22, and 32) having a flat conductive surface. Each keycap (11, 21, and 31) is mounted while being stored in each key switch storage part 6, having a rectangular flat surface, of the upper case 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention mainly relates to a key switch structure suitable for a small electronic device such as a mobile phone, a portable audio device, and an electronic pedometer, and particularly relates to prevention of erroneous input of adjacent key switches.

  Japanese Patent Application Laid-Open No. 8-227634 (Patent Document 1) discloses an erroneous input prevention structure for a pair of key switches arranged symmetrically via a partition formed in a housing. In this erroneous input prevention structure, the key switch has a movable contact portion disposed in the vicinity of one skirt portion of a bridge-shaped rubber spring having skirt portions on the left and right sides, and a fixed contact pattern on the substrate facing the movable contact. The pattern contact is arranged, a projection for preventing erroneous input is provided in the vicinity of the other skirt portion of the bridge-shaped rubber spring, and a key top is fixed to the upper side of the bridge-shaped rubber spring. . The pair of key switches are attached to the electronic device with the partition portion in between so that the protruding portion is close to the partition portion.

  With such a structure, the movable contact portions of the pair of key switches are arranged at positions farthest from the partition portion. Because of this structure, even when one of a pair of adjacent key switches is pressed down and a finger touches the end of the other key switch and the other key switch is pressed down, the other switch is Since the projection for preventing erroneous input contacts the circuit board, the movable contact does not contact the pattern contact.

However, this conventional key switch structure has a problem that the structure of the key top is complicated, and the space for providing the projection for preventing erroneous input and the contact part of the adjacent key switch need to be separated by a certain distance. is there. There is also a problem that it is difficult to maximize the key top in a limited space due to the partition provided in the housing.
JP-A-8-227634

    The problem to be solved by the present invention is that the layout of maximizing the arrangement space of the key top is possible in the limited space of the casing of the electronic device, and the key top of one of the adjacent key switches is provided. When the key is pressed, even if a finger touches the key top of the other switch, the other switch does not make an erroneous input.

  In order to solve the above-mentioned problem, in a switch having a movable contact having a flat conductive surface and a pair of fixed contact patterns, the movable contact is in contact with the pair of fixed contact patterns while being inclined in the key top arrangement direction. We focused on the phenomenon that there are times when it does not turn on.

  And the switch structure of the electronic device that solves the above problems, each of the movable contact of the flat conductive surface provided at the tip of the central portion of the dome-shaped rubber spring, a pair of fixed contact patterns formed on the substrate, A plurality of key switches from a key top that pushes down the movable contact are arranged in a predetermined arrangement direction on a casing without providing a partition between adjacent key tops, and the pair of fixed contact patterns The key tops were attached to the rectangular flat portion of the housing, spaced apart in the arrangement direction and symmetrically formed with respect to the center of the center of the dome-shaped rubber spring.

  According to the present invention, it is possible to achieve a layout that maximizes the arrangement space of the key top in a limited space of the casing of the electronic device, and when the key top of one switch of the adjacent key switch is pushed down. It was possible to provide a switch structure of an electronic device in which the other switch does not erroneously input even if a finger touches the key top of the other switch. In addition, the electronic pedometer to which the present invention is applied can maximize the arrangement of a plurality of key tops in a limited space of the casing, and thus its operability is improved.

  The electronic device switch structure according to the present invention includes a movable contact having a flat conductive surface provided at the center end of a dome-shaped rubber spring, a pair of fixed contact patterns formed on a substrate, and the movable contact. A plurality of key switches composed of key tops that push down the substrate are arranged in a predetermined arrangement direction in a housing without providing a partition between adjacent key tops, and the movable contact has a flat conductive surface. The pair of fixed contact patterns are spaced apart in the arrangement direction and symmetrically formed with respect to the center of the center of the dome-shaped rubber spring, and the key top is arranged in a rectangular plane of the housing. It is attached to the part.

  The switch structure of the electronic device according to the first embodiment of the present invention is such that the three key switches of the first key switch 10, the second key switch 20, and the third key switch 30 are housed in the key switch of the upper case 1 of the electronic pedometer. It is housed in the part 6 and attached according to the configuration described below. The electronic apparatus to which the present invention is applied is, for example, an electronic pedometer having a structure in which a plurality of key tops must be arranged on the same surface as the display unit 5, as shown in a plan view of FIG. This is an electronic device provided with a housing in which a sufficient arrangement space cannot be secured.

  The first key switch 10 has a pair of fixed contacts formed on the substrate 4 when a movable contact 12 having a flat conductive surface provided at the center end of the dome-shaped rubber spring 14 is lowered by the operation of the key top 11. This is a switch that contacts the pattern 13 and shorts it to turn it on. Further, the second key switch 20 is configured such that the movable contact 22 having a flat conductive surface provided at the front end of the central portion of the dome-shaped rubber spring 24 is lowered by the operation of the key top 21, and a pair of formed on the substrate 4. This is a switch that contacts the fixed contact pattern 23 and is turned on by short-circuiting it. Further, the third key switch 30 is configured such that a movable contact 32 having a flat conductive surface provided at the front end of the central portion of the dome-shaped rubber spring 34 is lowered by the operation of the key top 31 and a pair of formed on the substrate 4. It is a switch that contacts the fixed contact pattern 33 and is turned on by short-circuiting it. In short, the first key switch 10, the second key switch 20, and the third key switch 30 have the same size and function.

  The key top 11 of the first key switch 10 includes a downward stroke limiting portion 15 on both sides in the XX direction and an upward stroke limiting portion 16 on both sides in the YY direction. Similarly, the key top 21 of the second key switch 20 includes a downward stroke restricting portion 25 on both sides in the XX direction and an upward stroke restricting portion 26 on both sides in the YY direction. Further, the key top 31 of the third key switch 30 includes a downward stroke restricting portion 35 on both sides in the XX direction and an upward stroke restricting portion 36 on both sides in the YY direction.

  As shown in the plan view of FIG. 4, the key switch storage unit 6 has a length that is three times the horizontal width of the key top in the XX direction and a vertical width of the key top in the YY direction. It has a width with a gap of. Further, as shown in the cross-sectional views of FIGS. 1, 2, and 3, the key switch storage unit 6 has the same depth as the thickness of the upper case 1, and the upper part is stored in the key top with the perforated partition wall 6A as a boundary. The part and the lower part are dome-shaped rubber spring storage parts. The upper surface of the perforated partition wall 6A functions as a stopper surface that restricts the downward stroke of the key tops 11, 21, and 31.

  Under the key switch housing 6, the dome type rubber spring 14 of the first key switch 10, the dome type rubber spring 24 of the second key switch 10, and the third key switch 30 are arranged in the XX direction. The dome type rubber spring 34 is disposed and fixed to the circuit board 4. The lower surfaces of the key tops 11, 21, and 31 are bonded to the upper surfaces of the dome type rubber springs 14, 24, and 34, respectively.

  On the circuit board 4, fixed contact patterns 13, 23 and 33 are arranged at positions facing the movable contacts 12, 22 and 32 of the key switch, respectively. As shown in FIG. 5C, the fixed contact pattern 13 of the first key switch 10 is a pair of bifurcated fork-like patterns arranged at a predetermined interval in the XX direction. The pattern 13A and the right side are the ground pattern 13B. Similarly, the fixed contact pattern 23 of the second key switch 20 and the fixed contact pattern 33 of the third key switch 30 are a pair of symmetrically arranged in the XX direction at a predetermined interval in the first embodiment. A bifurcated fork pattern.

  Alternatively, as shown in FIG. 5A, the fixed contact pattern 13 of the first key switch 10 is a pair of semicircular switch patterns 13A and a ground pattern which are arranged at a predetermined interval in the XX direction. At the same time, the fixed contact pattern 23 of the second key switch 20 and the fixed contact pattern 33 of the third key switch 30 can be formed into a pair of semicircular switch patterns. Further, as shown in FIG. 5B, the fixed contact pattern 13 of the first key switch 10 includes a pair of rectangular switch patterns 13A and a ground pattern 13B which are arranged to be opposed to each other at a predetermined interval in the XX direction. At the same time, the fixed contact pattern 23 of the second key switch 20 and the fixed contact pattern 33 of the third key switch 30 can be formed into a pair of rectangular switch patterns.

  After the three key switches 10, 20, and 30 are attached to the upper case 1, the circuit board 4 is assembled at a predetermined position of the upper case 1, and the lower case 2 is disposed below the circuit board 4. And fix the lower case 2 with screws or the like. Then, the key tops 11, 21, 31 are arranged at predetermined positions of the upper case 1, and finally the decorative plate 3 is attached to the upper case 1. In this way, the key switch structure is completed. Of course, before the upper case 1 is assembled, the circuit board 4 is mounted with electronic components such as a CPU constituting an electronic pedometer.

  In the key switch structure of the first embodiment configured as described above, the positional relationship of the three key switches 10, 20 and 30 when all are in the normally-off state is as shown in FIGS. . That is, in the first key switch 10, the key top 11 is pushed upward by the elasticity of the dome-shaped rubber spring 14, but the upper stroke limiting portion 16 is in contact with the lower surface of the decorative plate 3 and is limited at this position. ing. Similarly, in the second key switch 20, the key top 21 is pushed upward by the elasticity of the dome-shaped rubber spring 24, but the upper stroke restricting portion 26 is in contact with the lower surface of the decorative plate 3 and restricted at this position. Has been. Further, in the third key switch 30, the key top 31 is pushed upward by the elasticity of the dome-shaped rubber spring 34, but the upper stroke restricting portion 36 is in contact with the lower surface of the decorative plate 3 and is restricted at this position. Yes.

  The movable contact 12 having the flat conductive surface of the first key switch 10, the movable contact 22 having the flat conductive surface of the second key switch 20, and the movable contact 32 having the flat conductive surface of the third key switch 30 are: Are spaced apart from the corresponding fixed contact patterns 13, 23 and 33 by a first predetermined distance. Further, the downward stroke restriction portion 15 of the key top 11 of the first key switch 10, the downward stroke restriction portion 25 of the key top 21 of the second key switch 20, and the downward stroke restriction of the key top 31 of the third key switch 30. The portion 35 is separated from the upper surface of the perforated partition wall 6A by a second predetermined interval. Naturally, the second predetermined interval is slightly larger than the first predetermined interval.

  When the center key top 21 is pushed down by the user's finger and at the same time the finger is partially touched and the left and right key tops 11 and 31 are pushed down, as shown in FIG. Is turned on, and the left and right first key switches 10 and the third key switch 30 remain off.

  That is, since the key top 21 of the second key switch at the center is pressed down in a horizontal state, the movable contact 22 having a flat conductive surface is a pair of opposing forked fork-shaped fixed contact patterns, that is, the left side It is in horizontal contact with both the switch pattern and the right ground pattern. Accordingly, the second key switch 20 at the center is in an on state. The left and right downward stroke restricting portions 25 of the key top 21 abut against the upper surface of the opposed perforated partition wall 6A, and the depression of the key top 21 is restricted at this position.

  On the other hand, since the key top 11 of the left first key switch 10 is tilted and pushed down to the right, the movable contact 12 having a flat conductive surface is tilted and abuts against the right ground pattern. It does not touch the pattern. Therefore, the left first key switch 10 remains off. The lower stroke limiter 15 on the right side of the key top 11 of the first key switch 10 is in contact with the upper surface of the opposed perforated partition wall 6A, but the lower stroke limiter 15 on the left side is separated without contacting. ing. In this way, the depression of the key top 11 is restricted at this position in this inclined state.

  Similarly, since the key top 31 of the right third key switch 30 is tilted and pushed down to the left, the movable contact 32 having a flat conductive surface is tilted and abuts against the switch pattern on the left. It does not touch the ground pattern. Accordingly, the right key switch 30 remains off. The lower stroke restricting portion 15 on the left side of the key top 31 of the third key switch 30 is in contact with the upper surface of the opposed perforated partition wall 6A, but the lower stroke limiting portion 15 on the right side is not in contact but separated. ing. In this way, the depression of the key top 31 is restricted at this position in this inclined state.

  As described above, the switch structure of the electronic device according to the present invention has been described in detail by the first embodiment configured by three key switches. However, the present invention is not limited to this embodiment, and two key switches or It is also possible to configure with four or more key switches. Of course, the dome type rubber spring pushed up to the normal off position and lowered by the key top operation is not limited to the illustrated one.

FIG. 5 is a cross-sectional view of the key switch cut along line XX in FIG. 4, and is a cross-sectional view showing the positional relationship of the three key switches when all are in a normally-off state. FIG. 5 is a cross-sectional view of the key switch cut along line YY in FIG. 4, and is a cross-sectional view illustrating a state in which one key switch is attached to a housing when a central key switch is operated with a finger. FIG. 4 is a cross-sectional view of the key switch cut along line XX in FIG. 4, when the key top of the center key switch is pressed down with a finger and the same finger touches the key top of the adjacent key switch on the left and right at the same time. It is sectional drawing which shows the positional relationship of three key switches. It is a top view of the electronic pedometer which is an electronic device, and is a top view which shows the positional relationship of three key switches when all are in a normal-off state. It is a top view of a fixed contact pattern, (A) is a pair of semicircular fixed contact patterns, (B) is a pair of rectangular patterns, (C) is a pair of bifurcated fork patterns.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper case 2 Lower case 2 Board | substrate 3 Decoration board 4 Circuit board 5 Display part 6 Key switch accommodating part 6A Perforated partition 10 1st key switch 11 Key top 12 Movable contact 13 Fixed contact pattern 13A Switch pattern 13B Ground pattern 14 Rubber switch 20 second key switch 21 key top 22 movable contact 23 fixed contact pattern 23a switch pattern 23b ground pattern 24 rubber switch 30 third key switch 31 key top 32 movable contact 33 fixed contact pattern 33a switch pattern 33b ground pattern 34 rubber switch

Claims (5)

A plurality of keys each composed of a movable contact having a flat conductive surface provided at the front end of the central portion of the dome-shaped rubber spring, a pair of fixed contact patterns formed on the substrate, and a key top for pushing down the movable contact. In a switch structure of an electronic device in which a switch is arranged in a predetermined arrangement direction on a casing without providing a partition between adjacent key tops,
The pair of fixed contact patterns are spaced apart in the arrangement direction and symmetrically formed with respect to the center of the center of the dome-shaped rubber spring, and the key top is a rectangle of the casing A switch structure for an electronic device, wherein the switch structure is attached to a planar arrangement portion.   The rectangular planar arrangement portion has a length and width in which the key tops of the plurality of key switches can be arranged adjacent to each other, a horizontal width in which only one key top of the switch can be arranged, and 2. The electronic device switch structure according to claim 1, wherein the switch structure has the same depth as the key switch.   The switch structure for an electronic device according to claim 1, wherein the pair of fixed contact patterns is a pair of semicircular patterns.   The switch structure for an electronic device according to claim 1, wherein the pair of fixed contact patterns is a pair of rectangular patterns.   2. The electronic device switch structure according to claim 1, wherein the pair of fixed contact patterns are a pair of forked patterns.

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