JP5388871B2 - Multi-directional switch member and electronic apparatus having the same - Google Patents

Description

  The present invention relates to a multidirectional switch member operable in multiple directions and an electronic apparatus having the same.

  A multi-directional switch member that can be pressed in at least four directions (up, down, left, and right) is provided above the operation panel surface of many mobile phones. For example, when the left key of the multi-directional switch member is pressed, the incoming call history is displayed, when the right key is pressed, the outgoing call history is displayed, when the up key is pressed, the phone book is displayed, and when the down key is pressed, the calendar is displayed. As a structure of the multi-directional switch member that exhibits such a function, for example, it has a swing structure so that the key top operated by the operator can be pressed in four directions, up, down, left, and right, and there is a lower part thereof. A device for inputting a switch on a printed circuit board is known (see Patent Document 1).

JP 2008-123907 (Abstract, Claim 1)

  By the way, by tracing or rotating the periphery of the multidirectional switch member along the circumferential direction, a function different from that in the case of pressing each direction alone can be exhibited. For example, if the user traces clockwise or counterclockwise so as to rotate around the multidirectional switch member, the map displayed on the display unit can be scrolled upward or downward. Prior to the present invention, the present inventor considered the following configuration as a multidirectional switch member exhibiting such a function.

  FIG. 11 is a front view of a mobile phone provided with the multidirectional switch member previously considered by the present inventor. FIG. 12 is a side view showing a state in which the circular operation board and the printed circuit board constituting the multidirectional switch member shown in FIG. 11 are arranged to face each other. 13 is a rear view of the operation plate shown in FIG.

  As shown in FIG. 11, one multidirectional switch member 210 is disposed above the lower case side of the mobile phone 200. The multidirectional switch member 210 includes a circular operation plate 220 on the front side. As shown in FIGS. 12 and 13, a total of eight contacts 230 are arranged on the back surface of the operation plate 220. As shown in FIG. 12, the operation plate 220 is disposed so as to face the printed circuit board 240 that is one component of the multidirectional switch member 210. A contact electrode group 250 is formed on the front surface of the printed circuit board 240 immediately below each contact 230. As shown in FIG. 12, each contact electrode group 250 includes two electrodes 260 and 260 that are close to each other in a non-contact state. Each contact 230 is a substantially hemispherical elastomer in which a conductive material such as carbon black is dispersed. Further, it is fixed to the back surface of the operation plate 220.

  When a part near the outer periphery of the operation plate 220 is pressed toward the printed circuit board 240, a plurality of contacts 230 in the vicinity of the pressed portion come into contact with the contact electrode group 250 directly below each of the contact electrodes 250. The electrical resistance value between the electrodes 260 and 260 constituting the circuit becomes smaller. When the pressure is large, the contact area where the contact 230 is in contact with the contact electrode group 250 immediately below it is large and the electrical resistance value is small. On the other hand, when the pressure is small, the contact area is small and the electrical resistance value is large. For this reason, the voltage value of the contact electrode group 250 varies according to the contact area where the tip of the contact 230 is in contact with the contact electrode group 250. When a plurality of contacts 230 are in contact with the respective contact electrode groups 250 immediately below them, the voltage values in the respective contact electrode groups 250 are different. Therefore, by generating a vector from the position and voltage value of each contact electrode group 250, From the composition of the vectors, the pressing direction and the size in the surface of the operation plate 220 can be detected. For this reason, if the user traces the operation plate 220 so as to rotate in a certain circumferential direction, the direction of the vector changes along the rotation operation direction every moment, so that the control unit (not shown) of the mobile phone 1 is It can be determined that a rotation operation is being performed.

  However, the multi-directional switch member 210 having the above structure has the following points to be improved.

  FIG. 14 is a diagram showing a state in which the operation plate constituting the multi-directional switch member of the mobile phone shown in FIG. 11 is traced so as to rotate in the arrow R direction. FIG. 15 is a schematic diagram illustrating a state in which the magnitude of pressing during the operation illustrated in FIG. 14 changes.

  As shown in FIG. 14, when the operator holds the mobile phone 200 with the right hand and performs the operation of tracing the operation plate 220 in the arrow R direction using the thumb S of the same hand, the pressing in the direction close to the base of the thumb S is performed. There is a tendency to weaken. In FIG. 15, the degree of pressing is indicated by the size of a hatched circle. Now, as shown in FIG. 15, the upper, right, lower, and left directions of the operation plate 220 are assumed to be north (N), east (E), south (S), and west (W), respectively. If you trace from north to clockwise, you can press in the range from north to east with sufficient force, but if you cross the east, it will begin to become difficult to press, and you will not be able to press very strongly until you reach the south. On the other hand, when you go south, power gradually enters, and you can press with enough force to go west and go north. That is, the range of SA shown in FIG. 15 (the range from the west to the north to the east) can be sufficiently pressed, but the range of the WA (the range from the east to the south) and the range of the MA (the range from the south to the west). ) Cannot be pressed with sufficient force. In particular, the range of WA is most difficult to push and tends to be a range where no force is applied. Even when the left-handed operator uses the thumb of the left hand, the pressure in the direction close to the base of the thumb is similarly weakened.

  As described above, when the operation plate 220 of the multidirectional switch member 210 is rotated, it cannot always be pressed with the same force, and the pressing force varies in the circumferential direction. In this case, in the region where the pressing force is weak (range from the east to the south and further to the west), the contact area where the contact 230 is in contact with the contact electrode group 250 becomes unstable, and erroneous detection of the pressing direction is likely to occur. . As a result, the display information is not scrolled smoothly, and there is a need for an improvement that allows smoother scrolling.

  The present invention has been made in view of the above demands, and an object thereof is to perform a smoother display operation when a multidirectional switch member is operated along its circumferential direction. .

  The inventor is one of the causes that the scroll of the display information is not smoothly performed when the operation plate of the multi-directional switch member developed earlier is rotated, when the contact tip contacts the contact electrode group, It was thought that the contact area of the contact could easily fluctuate. Accordingly, the present invention has been completed by pursuing a contact shape that makes it difficult for the contact area to vary when the tip of the contact contacts the contact electrode group.

  Specifically, one mode of the present invention for achieving the above-described object is to provide a swinging member that can swing in the front and back directions in the outer peripheral portion in a plurality of directions from the center in the surface, and a back direction of the swinging member. A printed circuit board disposed opposite to the swing member, the printed circuit board having a plurality of contact electrode groups composed of a plurality of electrodes at a position corresponding to the outer peripheral portion of the surface facing the swing member; A multi-directional switch member provided with a plurality of conductive elastic bodies facing the contact electrode group on the back surface of the swing member and arranged along the circumferential direction of the swing member, the conductive elastic body, This is a multidirectional switch member having a portion whose horizontal cross section is reduced toward the contact electrode group and having a tip parallel to the contact electrode group.

  Further, according to another aspect of the present invention, the conductive elastic body further exhibits an electrical resistance value of 2000 ohms or less when the load from above is 0.1 N, and when the load from above is 0.5 N. The multidirectional switch member exhibits an electric resistance value of 50% or more of the electric resistance value when the load is 0.1 N.

  Another embodiment of the present invention is a multi-directional switch member in which the conductive elastic body is disposed radially at eight positions from the center of the back surface of the swing member.

  According to another aspect of the present invention, there is provided a multidirectional switch further comprising a rotation operation plate capable of pressing the outer peripheral portion of the swing member in the front side direction of the swing member and capable of rotating in its own plane. It is a member.

  In addition, according to one aspect of the present invention, a swinging member that can swing in the front and back directions in a plurality of outer peripheral portions from the center in the plane, and a printing that is disposed to face the swinging member in the reverse direction of the swinging member. A printed circuit board having a plurality of contact electrode groups composed of a plurality of electrodes at a position corresponding to an outer peripheral portion of a surface facing the swing member, and a contact electrode group on the back surface of the swing member A plurality of conductive members which are arranged along the circumferential direction of the swing member and have a portion whose horizontal cross section becomes smaller toward the contact electrode group, and whose tip is a horizontal plane parallel to the contact electrode group. It is an electronic device which has a multidirectional switch member provided with an elastic elastic body.

  ADVANTAGE OF THE INVENTION According to this invention, when operating a multidirectional switch member along the circumferential direction, a smoother display operation can be performed.

FIG. 1 is a front view of a mobile phone which is an example of an electronic apparatus according to an embodiment of the present invention. FIG. 2 is a front view of the multi-directional switch member removed from the mobile phone shown in FIG. 3 is a cross-sectional view taken along line AA of the multidirectional switch member shown in FIG. FIG. 4 is an exploded view of the main part of the multidirectional switch member shown in FIG. FIG. 5 is an enlarged view showing a conductive elastic body disposed on the back surface of the swing member and the swing member of the multidirectional switch member. FIG. 6 is a view showing a state in which the PCB of the multidirectional switch member shown in FIG. 2 is face up. FIG. 7 is a diagram for explaining a situation in which a conductive elastic body having a spherical shape at the tip is cut by changing the distance X from the tip to produce a conductive elastic body for use in the test. FIG. 8 is a side sectional view showing in detail a portion where various conductive elastic bodies manufactured by the method shown in FIG. 7 are in contact with a specific contact electrode group on the PCB. FIG. 9 is a graph of the results in Table 2. FIG. 10 is a diagram showing a modification of the PCB shown in FIG. FIG. 11 is a front view of a mobile phone provided with the multidirectional switch member previously considered by the present inventor. FIG. 12 is a side view showing a state in which the circular operation board and the printed circuit board constituting the multidirectional switch member shown in FIG. 11 are arranged to face each other. 13 is a rear view of the operation plate shown in FIG. FIG. 14 is a diagram showing a state in which the operation plate constituting the multi-directional switch member of the mobile phone shown in FIG. 11 is traced so as to rotate in the arrow R direction. FIG. 15 is a schematic diagram illustrating a state in which the magnitude of pressing during the operation illustrated in FIG. 14 changes.

  Next, preferred embodiments of the multidirectional switch member and the electronic apparatus according to the present invention will be described with reference to the drawings. In the following embodiments, a mobile phone will be described as an example of an electronic device. However, the electronic device is not limited to a mobile phone, and may be a portable music playback device, a remote controller for operating a car navigation device, or the like. .

  FIG. 1 is a front view of a mobile phone which is an example of an electronic apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, a mobile phone 1 that is an example of an electronic apparatus according to this embodiment includes a multidirectional switch member 2 that can be operated in multiple directions. In this embodiment, the multidirectional switch member 2 enables multidirectional detection based on contact of contacts in a total of eight directions including four directions (up, down, left, and right) and diagonal directions when viewed from the front. The multidirectional switch member 2 is a substantially circular switch member that can detect not only multi-directions from the center but also the pressing of the central portion. However, the multi-directional switch member 2 may not be able to detect the pressing at the center, and may be detectable only in the multi-direction from the center. Further, the contact points of the multidirectional switch member 2 are not limited to the above eight directions, and may be provided only in four directions (up, down, left and right) or in one or more oblique directions in the four directions.

<1. Multi-directional switch member structure>
FIG. 2 is a front view of the multi-directional switch member removed from the mobile phone shown in FIG. 3 is a cross-sectional view taken along line AA of the multidirectional switch member shown in FIG.

  As shown in FIGS. 2 and 3, the multidirectional switch member 2 has a thin cylindrical dish-shaped body 10 and a diameter smaller than the diameter of the inner bottom surface of the dish-shaped body 10, and the inner bottom surface of the dish-shaped body 10. A substantially disk-shaped printed circuit board (PCB) 20 disposed on the upper surface, and a substantially disk-shaped swinging member 30 supported on the outer peripheral portion of the front surface of the PCB 20 and disposed in the front direction of the PCB 20, A central key 50 disposed substantially at the center of the front surface of the swing member 30 and a substantially annular multidirectional operation plate 60 disposed through the center key 50 through the front surface of the swing member 30. A substantially annular rotary operation plate 70 that is disposed through the central key 50 so as to cover the multidirectional operation plate 60 from the front direction, the front side surface of the multidirectional operation plate 60, and the front side surface thereof. A substantially ring-shaped friction reducing member 8 disposed between the inner surface of the rotary operation plate 70 opposite to the inner surface. A substantially annular frame 90 disposed inside the dish-like body 10 so as to surround the PCB 20, the swinging member 30, the multidirectional operation plate 60 and the rotation operation plate 70 from the sides thereof, Is provided.

  The dish-like body 10 is made of a thin hard resin, and is a thin, substantially cylindrical member whose length in the height direction is smaller than the diameter of the bottom surface. The bottom surface of the dish-like body 10 is provided with one or a plurality of through holes (not shown) for inserting lead wires connected to electrodes and wirings formed on the front side surface of the PCB 20. . Moreover, the upper end part of the side surface of the dish-shaped body 10 is bent outward to make it easier to insert a frame body 90 described later from the opening of the dish-shaped body 10 into the inside thereof.

  The PCB 20 is preferably a glass epoxy circuit board in which a cloth knitted with glass fibers is impregnated with an epoxy resin. However, a ceramic substrate made of a glass composite substrate, alumina, or the like may be adopted as the PCB 20. On the front side surface of the PCB 20, a single metal dome 28 is provided at the approximate center thereof, and a plurality of contact electrode groups (described later) so as to surround the metal dome 28. Metal domes 24, 26, etc. are arranged respectively. Although only two metal domes can be seen on the radially outer side of the contact electrode group in FIG. 3, there are actually four metal domes, as will be described later with reference to FIG. Here, only the metal dome that can be seen in FIG. 3 is indicated by a symbol, and “etc.” is used to include other metal dome. The metal domes 24, 26, 28, etc. have almost the same shape, and are arranged so as to cover a ring-shaped electrode substantially equal in diameter to the ring-shaped electrode and a dot-shaped electrode disposed inside the ring-shaped electrode. (Not shown). However, the central metal dome 28 and the metal domes 24 and 26 arranged on the outer periphery thereof may have different forms.

  While the ring-shaped electrode is always electrically connected to the outer periphery of the metal domes 24, 26, 28, etc., the dot-shaped electrode is in a state where the metal domes 24, 26, 28, etc. are not pressed. It is not electrically connected to both the metal domes 24, 26, 28 and the like and the ring-shaped electrode. When the metal domes 24, 26, 28, and the like are pushed toward the PCB 20 and become more than a certain force, the tops of the metal domes 24 are recessed and are electrically connected to the dot-like electrodes. As a result, the ring-shaped electrode and the dot-shaped electrode are brought into conduction, and the switch is turned on.

  The swing member 30 is a member for performing an input operation of a switch composed of an elastic material such as a thermoplastic elastomer, a thermosetting elastomer, or natural rubber. As a material of the swing member 30, a silicone rubber can be preferably used. The oscillating member 30 has substantially the same diameter as the PCB 20 in the back direction, and is composed of an annular member 31, a flexible dome 32, and a disc 33 in order from the radially outer side to the center. This is an integrally molded member. However, the oscillating member 30 does not necessarily need to be an integrally formed member of each of the above members, and may be formed by joining and bonding a plurality of members. When the rocking member 30 receives a pressure from the rotary operation plate 70 arranged in the front direction at the outer peripheral portion in a plurality of directions from the center in the surface, the rocking member 30 rocks in the front and back direction (the double arrow Z direction in FIG. 3). Is possible.

  The annular member 31 that forms the outermost portion of the swing member 30 is a portion that is placed on the outer peripheral portion of the front side surface of the PCB 20 in a state in which the PCB 20 and the side end surface are substantially aligned. Further, the bendable dome 32 formed inside the annular member 31 is in a state where the disk 33 formed inside the bendable dome 32 is lifted from the PCB 20 by the pressure applied to the swing member 30 and the release thereof. It is a flexible member necessary for reversibly performing the state of sinking toward the PCB 20. The circular plate 33 includes a plurality of pressing elements 34, 36 and the like projecting in the back direction on the outer peripheral portion of the back surface, and one press projecting in the back direction in the central portion of the back surface. A child 38 is provided. Although only two pressing elements are provided on the outer peripheral portion of the back surface of the disc 33 in FIG. 3, there are actually four pressing elements as described later with reference to FIG. Here, only the pressing elements visible in FIG. 3 are indicated by reference numerals, and “etc.” is used to include other pressing elements. The pressing elements 34, 36, 38, etc. of the disc 33 are provided at positions facing the metal domes 24, 26, 28, etc., respectively. A pedestal 39 is provided at the center of the front surface of the disc 33. The pedestal 39 is a part for fixing the center key 50.

  A plurality of conductive elastic bodies 41, 42, 43, 44, etc. are provided on the back surface of the disk 33 from the pressing element 38 to the outer side in the radial direction of the disk 33 so as to surround the pressing element 38. Although only four are visible in FIG. 3, there are actually eight as shown in FIG. Here, only the conductive elastic bodies visible in FIG. 3 are indicated by reference numerals, and “etc.” is used to include other conductive elastic bodies. The conductive elastic bodies 41, 42, 43, 44, etc. are elastic bodies having a diameter that decreases toward the contact electrode group, which will be described later, in the vicinity of the tip portion, and whose tip has a plane parallel to the contact electrode group. is there. The conductive elastic bodies 41, 42, 43, 44, etc. are made of a flexible material so that they can be elastically deformed after contact with the contact electrode group formed on the front surface of the PCB 20. In addition, a conductive material is dispersed in the conductive elastic bodies 41, 42, 43, 44 and the like in order to impart conductivity. Examples of the conductive material include carbon black, metal, and the like, but carbon black that can easily manufacture a material having a small particle size (nano-level particles) and is easy to handle is more preferable. The mixing amount of the conductive material is 5 to 50 weights with respect to the total weight of the base material and the conductive material from the viewpoint of enhancing the conductivity and maintaining the elasticity of the conductive elastic bodies 41, 42, 43, 44 and the like. %, And more preferably 15 to 35% by weight.

  The center key 50 is preferably made of a hard resin. A flange 51 having a diameter larger than that of the upper portion is formed at the bottom of the center key 50. Moreover, the flange part 51 is larger diameter than the base 39 which fixes it. However, the center key 50 may be made of metal.

  The multidirectional operation plate 60 is a substantially annular member, and is a member that transmits the pressure from the rotation operation plate 70 to the swing member 30. The multidirectional operation plate 60 is preferably made of a hard resin. The hole at substantially the center of the multidirectional operation plate 60 is formed to be sufficiently larger than the outer diameter of the center key 50 so that the center key 50 is disposed and a part of the rotation operation plate 70 described later can be inserted. Yes. The outer bottom portion of the multidirectional operation plate 60 includes an outward projecting portion 61 that projects radially outward along the outer periphery thereof. The outward projecting portion 61 is formed to be flush with the bottom surface of the multidirectional operation plate 60. The outward projecting portion 61 projects outward from the dome 32 of the swing member 30. In addition, the inner peripheral surface of the hole at the approximate center of the multidirectional operation plate 60 is provided with an inward protruding portion 62 that protrudes toward the center of the hole along the inner peripheral surface. The inward projecting portion 62 is formed so as to be flush with the front side surface of the multidirectional operation plate 60. The protruding length of the inward protruding portion 62 is shorter than the protruding length of the outward protruding portion 61.

  The rotation operation plate 70 is a substantially annular key capable of pressing the outer peripheral portion of the swing member 30 in the front side direction of the swing member 30 and capable of rotating in its own plane. For example, by rotating the rotary operation plate 70 in the direction of the arrow R shown in FIG. 3 (which may be opposite to the direction of the arrow R), multiple directions are arranged in the reverse direction at any orientation during the rotation. The operation plate 60 and the swing member 30 can be pressed in the direction of the PCB 20. The rotary operation plate 70 is preferably made of hard resin or elastomer. A hole (described later) in the approximate center of the rotary operation plate 70 is formed slightly larger than the outer diameter of the center key 50 and smaller than the approximately central hole of the multidirectional operation plate 60. A recess 71 that is recessed inward is formed along the circumferential direction from the back surface of the rotary operation plate 70. The recess 71 opens to the multi-directional operation plate 60 side, and rotates in the vicinity of the inner top surface while the outer surface is substantially vertical, the inner bottom surface is horizontal, and the inner surface is substantially vertical up to the middle of the inner top surface. The operation plate 70 has a shape recessed toward the inside in the radial direction. For this reason, the claw part 72 which protrudes toward the radial direction outer side of the rotation operation board 70 exists inside the opening surface of the recessed part 71. The recess formed inward of the claw portion 72 of the recess 71 is formed in a size that can be fitted into the inward protruding portion 62 of the multidirectional operation plate 60.

  The surface on the front side of the rotary operation plate 70 is an inclined surface 73 that is inclined downward from the radially outer side toward the inner side. However, you may make the inclined surface 73 into the surface which inclines below toward a horizontal surface or the outer side.

  The friction reducing member 80 is a substantially disc-shaped sheet disposed between the front side surface of the multidirectional operation plate 60 and the inner top surface of the recess 71 of the rotary operation plate 70. The friction reducing member 80 is preferably made of a fluorine-based resin, particularly polytetrafluoroethylene. The friction reducing member 80 is preferably fixed to the front surface of the multidirectional operation plate 60 by adhesion or the like. As a result, the rotary operation plate 70 that rotates relative to the multidirectional operation plate 60 can rotate so as to slide on the friction reducing member 80. However, the friction reducing member 80 may be fixed to the inner top surface of the recess 71 by adhesion or the like. Further, the friction reducing member 80 can be arranged not only on the front surface of the multidirectional operation plate 60 but also on other surfaces that may come into contact with the recess 71 of the rotary operation plate 70.

  The frame 90 is preferably made of metal or hard resin. The frame 90 has a front side surface 93 that is radially inward, and a step surface 94 that is radially outward from the front side surface 93 and that is stepped down one step toward the inner bottom side of the dish-like body 10. A hole 95 is formed in the center of the frame 90 so as to penetrate in the front and back direction. The hole 95 is an area for enclosing the PCB 20, the swing member 30, the multidirectional operation plate 60, and the rotation operation plate 70 from their side surfaces. The hole 95 is formed by changing the diameter in three steps in the front and back direction. The vicinity of the bottom opening of the hole 95 is formed in the largest diameter, and is mainly an area where the PCB 20 and the annular member 31 of the swing member 30 are arranged. A middle region of the hole 95 is formed with a small diameter from the vicinity of the above-described bottom opening to the inside of the first step, and mainly the outward projections of the dome 32, the circular plate 33, and the multidirectional operation plate 60 of the swing member 30. This is an area where 61 is arranged. In particular, the middle region is formed in a sufficient size so that the outward projecting portion 61 does not contact the inner wall of the hole 95 in the front and back direction and the radially outer side. The vicinity of the opening in the front direction of the hole 95 is formed to have a smaller diameter than the middle region by an inward projecting portion 92 that is flush with the front side surface 93 and extends inward in the radial direction. This is an area where 70 is arranged. Further, a fixing portion 96 is formed on the outside of the frame body 90 so that the dish-like body 10 and the frame body 90 can be fixed. In this embodiment, the fixing portion 96 is a protrusion that can be housed on the frame body 90 side and project outward in the radial direction of the frame body 90, and can pass through a slit (not shown) formed on the side surface of the dish-like body 10. However, it is not limited to this as long as it is a member that can fix the dish-like body 10 and the frame body 90.

  In the mobile phone 1 shown in FIG. 1, only the portion inside the frame body 90 of the multidirectional switch member 2 is visible. That is, the portion on the outer side in the radial direction from the frame 90 is housed inside the case of the mobile phone 1. However, the outer side in the radial direction from the step surface 94 of the frame 90 may be housed inside the case of the mobile phone 1.

  FIG. 4 is an exploded view in which the main part of the multidirectional switch member is exploded in the front and back direction. In FIG. 4, the dish-like body 10 and the frame body 90 are excluded.

  On the inner peripheral surface of the substantially central hole of the multidirectional operation plate 60, an inward projecting portion 62 that is fitted into the recess 71 of the rotary operation plate 70 is formed. As a result, a step is formed on the inner peripheral surface of the hole, and the large hole 63 and the small diameter hole 64 continue from the swing member 30 toward the rotation operation plate 70 in the substantially central hole. It has a form. Further, a step is also formed on the inner peripheral surface of the substantially central hole of the rotary operation plate 70, and the substantially central hole is formed with a large-diameter hole 76 from the multidirectional operation plate 60 in the front direction, The small-diameter hole 77 is continuous.

  The friction reducing member 80 is fixed to the front surface of the multidirectional operation plate 60 by adhesion. A rotary operation plate 70 is attached to the front side surface of the multidirectional operation plate 60 to which the friction reducing member 80 is fixed. During this attachment, the inward protruding portion 62 of the multidirectional operation plate 60 contacts the claw portion 72 at the opening of the recess 71 of the rotary operation plate 70, but the length of the contacting portion is short, The inward projecting portion 62 and / or the claw portion 72 is slightly deformed, and the inward projecting portion 62 passes through the claw portion 72 and enters the recess 71.

  The center key 50 is fixed to the base 39 of the swing member 30 by adhesion or the like. The PCB 20 is fixed to the annular member 31 of the swing member 30 by adhesion or the like. In a state where the swing member 30 is fixed to the PCB 20, the pressers 34, 36, 38 and the like do not dent the metal domes 24, 26, 28 and the like. Further, the back surface of the multidirectional operation plate 60 and the front surface of the disc 33 constituting the swing member 30 are fixed by bonding and / or screwing. The flange portion 51 of the center key 50 cannot be inserted into the hole 77 of the rotary operation plate 70, and the center key 50 is pressed in the region behind the hole 76 by being pressed from the top surface and released. It is movable.

  FIG. 5 is an enlarged view showing a conductive elastic body disposed on the back surface of the swing member and the swing member of the multidirectional switch member.

  One pressing element 38 is provided in the approximate center of the back surface of the swing member 30. Further, pressers 34, 35, 36, and 37 are provided at equal intervals (center angle: approximately 90 degrees) along the circumferential direction of the disk 33, radially outward from the center and in the vicinity of the dome 32. It has been. The pressing members 34, 35, 36, 37, and 38 are fixed separately from the disk 33, but may be integrally formed of the same material as the disk 33. In the region radially inward of the pressing elements 34, 35, 36, 37, the conductive elastic bodies 41, 42, 43, 44, are equally spaced along the circumferential direction of the disk 33 (center angle: 45 degrees). 45, 46, 47, 48 are provided. The conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48 are fixed separately from the disk 33. Since the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48 need to contact the contact electrode group formed on the front surface of the PCB 20, the metal dome 24 that protrudes from the contact electrode group. , 26, 28, and the like, the tip thereof is provided so as to be close to the front surface of the PCB 20.

  The conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, and 48 are all in the same form, and a cylinder having the same bottom area and a substantially hemispherical body are joined to each other at their bottom surfaces, thereby forming a substantially hemispherical body. It has the shape which cut off the front-end | tip part horizontally. That is, taking the conductive elastic body 44 as an example, the tip is a horizontal plane 44a, and a curved surface 44b is formed that has an arc slightly outward from the horizontal plane 44a. The vertical side surface 44c is substantially perpendicular to the peripheral edge of the curved surface 44b. And a horizontal surface 44d is formed at the peripheral end of the vertical side surface 44c. As an example of a suitable configuration of the conductive elastic body 44 and the like, the diameter D1 of the horizontal surface 44a at the tip is 1.0 to 2.0 mm, and the diameter D2 of the horizontal surface 44d joined to the disk 33 is 2.5 to 2.5. 3.0 mm, the height (length) H1 of the vertical side surface 44c is 0.1 to 0.5 mm, and the height (length) H2 between the horizontal surfaces 44a and 44d is 0.5 to 0.9 mm. When the swinging member 30 is pressed toward the PCB 20, the horizontal surfaces 41a, 42a, 43a, 44a at the tips of the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48 in the vicinity of the pressed position. , 45a, 46a, 47a, 48a are in contact with the contact electrode group immediately below them. As the strength of pressing increases, the curved surfaces 41b, 42b, 43b, 44b, 45b, 46b, 47b, 48b of the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48 are also contact electrodes. Get in touch with the group.

  In addition, each length of the above-mentioned electroconductive elastic body 44 is only an example of suitable length, and is not limited to these. As long as the tip is a horizontal plane, the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, and 48 may have any form. For example, the curved surfaces 41b, 42b, 43b, 44b, 45b, 46b, 47b, and 48b can be tapered flat inclined surfaces. Furthermore, the horizontal planes 41a, 42a, 43a, 44a, 45a, 46a, 47a, and 48a are not limited to a circle, and may be an ellipse or a polygon such as a rectangle.

  FIG. 6 is a diagram illustrating a state in which the PCB of the multidirectional switch member is face up.

  A printed wiring 100 including a plurality of contact electrode groups is formed on the front side surface of the PCB 20. In the printed wiring 100, contact electrode groups 101, 102, 103, 104, 105, 106, are located at positions corresponding to the respective conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48. 107 and 108 are formed. The contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108 are made conductive by contact of the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48 provided on the swing member 30. It becomes possible. The contact electrode groups 101, 103, 105, and 107 are all contact electrode groups having the same form, and are substantially one semi-circular comb electrode radially outward from the center of the PCB 20 and a substantially semi-circular electrode radially inward. One comb electrode is arranged in a state where the comb teeth are meshed so as not to contact each other. On the other hand, the contact electrode groups 102, 104, 106, 108 are contact electrode groups having the same form, and are substantially two fan-shaped comb-shaped electrodes on the radially outer side and one generally semicircular electrode on the radially inner side. These comb-teeth electrodes are arranged in a state where the comb-teeth are meshed so as not to contact each other. The contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108 are respectively connected to the comb-shaped electrodes and the semi-comb-shaped electrodes on the outer side in the radial direction by wirings 110, 111, 112, 113, 114, 115, 116 and 117 are connected. The contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108 are formed by connecting the comb electrodes on the radially inner side to the wiring 120 except between the contact electrode group 103 and the contact electrode group 104. , 121, 123, 124, 125, 126, 127. However, between the contact electrode group 103 and the contact electrode group 104, the comb electrodes on the radially inner side may be connected by wiring.

  In addition, here, one electrode body is formed by one comb-tooth electrode arranged on the outer side in the radial direction and one half comb-teeth electrode arranged on both sides thereof. That is, four electrode bodies are formed on the front side surface of the PCB 20. As described above, by forming the four electrode bodies, the operation direction can be determined based on the ratio of the voltages in the respective electrode bodies. As an example, the four electrode bodies are allocated in four directions in the upper, lower, left and right directions within the surface of the PCB 20. Assuming that the voltage ratio of each electrode body becomes 10: 10: 0: 0 when a certain direction of the rotary operation plate 70 is pressed in the direction of the PCB 20, a vector in each direction is calculated based on the voltage ratio. As a result, vectors having the same size are generated in the upward direction and the right direction. Next, as a result of combining these vectors and generating a combined vector in the diagonally right direction, the operation direction can be determined as the diagonally right direction.

  When each conductive elastic body 41, 42, 43, 44, 45, 46, 47, 48 is brought into contact with each contact electrode group 101, 102, 103, 104, 105, 106, 107, 108, the pressure at the time of the contact The contact area between each contact electrode group 101, 102, 103, 104, 105, 106, 107, 108 and each conductive elastic body 41, 42, 43, 44, 45, 46, 47, 48 changes according to the above. . As a result, the electric resistance value between the comb electrodes (or between the half comb electrodes and the comb electrodes) becomes small. That is, each conductive elastic body 41, 42, 43, 44, 45, 46, 47, 48 is a comb that constitutes each contact electrode group 101, 102, 103, 104, 105, 106, 107, 108. It exhibits a variable resistance function that can change the electrical resistance value between the tooth electrodes (or between each half comb electrode). When the electric resistance value between the comb electrodes (or between the half comb electrodes and the comb electrodes) becomes small and the voltage value at that portion passes a certain threshold value, the switch can be turned on. As described above, the tips of the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, 48 are horizontal surfaces 41a, 42a, 43a, 44a, 45a, 46a, 47a, 48a. Therefore, the threshold value of the voltage value is determined when each horizontal plane 41a, 42a, 43a, 44a, 45a, 46a, 47a, 48a contacts each contact electrode group 101, 102, 103, 104, 105, 106, 107, 108. It is preferable to set a value larger than the voltage value. When each horizontal plane 41a, 42a, 43a, 44a, 45a, 46a, 47a, 48a comes into contact with each contact electrode group 101, 102, 103, 104, 105, 106, 107, 108, the threshold value is surely reached. Because. As described above, in this embodiment, the “switch is on” state is not only a state in which electrodes in a non-contact state are brought into conduction, but also a detection value (electric resistance value, It can be interpreted in a broad sense to include a state in which a current value has passed a certain threshold value.

  On the front side surface of the PCB 20, radially outside the contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108, at positions facing the pressers 34, 35, 36, 37. In this case, one metal dome 24, 25, 26, 27 is disposed. Further, one metal dome 28 is disposed at a position facing the pressing element 38. When the outer peripheral portion of the surface of the rotary operation plate 70 or the center key 50 is pressed toward the PCB 20, the metal domes 24, 25, 26, 27, and 28 corresponding to the pressed positions can be recessed. As a result, each central portion of the metal domes 24, 25, 26, 27, and 28 is in contact with the dot-like electrode directly below, and is always connected to the metal domes 24, 25, 26, 27, and 28. And the dot-shaped electrode are electrically connected, and the switch is turned on. The conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, and 48 are used to press the metal domes 24, 25, 26, 27, and 28 to turn on the switches. The metal contacts the contact electrode groups 101, 102, 103, 104, 105, 106, 107, and 108 so that the voltage value is larger than the pressure required to turn on the switch after passing a certain threshold value. The material, shape, and the like of the domes 24, 25, 26, 27, and 28 are determined.

<2. Evaluation of conductive elastic bodies of various shapes>
FIG. 7 is a diagram for explaining a situation in which a conductive elastic body having a spherical tip is cut by changing the distance X from the front end to produce a conductive elastic body for use in an evaluation test.

  In the original conductive elastic body, as shown in FIG. 7, the tip has a spherical shape with a radius of curvature R = 3.0 mm, the diameter of the bottom surface opposite to the tip (bottom diameter) is 3.0 mm, The height H from the bottom surface to the position of transition to the spherical surface is 0.4 mm, the tip has a spherical shape with a radius of curvature R = 2.5 mm, and the diameter (bottom diameter) of the bottom surface opposite to the tip is 2.5 mm. Thus, two types of conductive elastic bodies having a height H of 0.3 mm from the bottom surface to the position of transition to the spherical surface were used. Two kinds of original conductive elastic bodies are produced by the following method. Conductivity of silicone rubber compound (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KE 951-U) and 40 parts by weight of acetylene black (manufactured by Denki Kagaku Kogyo Co., Ltd.) with a volume resistivity of about 5 ohms. A rubber master batch (manufactured by Shin-Etsu Polymer Co., Ltd., product name: 87C40P-1) is prepared, and 50 parts by weight of the conductive rubber master batch and an insulating silicone rubber compound (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KE 961). -U) 50 parts by weight were kneaded, vulcanized and molded to produce an original conductive elastic body of 20% by weight of carbon black. From two kinds of original conductive elastic bodies, the distance X from the tip to the cut surface is changed within a range of 0.05 to 0.30 mm, and the total six kinds of conductive elastic bodies 41 having different areas of the horizontal surface of the tip are obtained. Each was produced.

In the case of a conductive elastic body having a bottom diameter of 3.0 mm and a tip curvature radius of 3.0 mm, the tip horizontal surface area (tip surface area) when X = 0.05 mm is 0.30π mm ² . . Similarly, the tip surface area when X = 0.10 mm is 0.59π mm ² . The tip surface area when X = 0.15 mm is 0.88πmm ² . The tip surface area when X = 0.20 mm is 1.17πmm ² . The tip surface area when X = 0.25 mm is 1.44π mm ² . The tip end face area when X = 0.30 mm is 1.72π mm ² .

In the case of a conductive elastic body having a bottom diameter of 2.5 mm and a tip radius of curvature of 2.5 mm, the tip face area when X = 0.05 mm is 0.25πmm ² . Similarly, the tip surface area when X = 0.10 mm is 0.49π mm ² . The tip surface area when X = 0.15 mm is 0.73π mm ² . The tip surface area when X = 0.20 mm is 0.96π mm ² . The tip surface area when X = 0.25 mm is 1.19πmm ² . The tip surface area when X = 0.30 mm is 1.42πmm ² .

  FIG. 8 is a side sectional view showing in detail a portion where various conductive elastic bodies manufactured by the method shown in FIG. 7 are in contact with a specific contact electrode group on the PCB.

  The contact electrode group 101 and the like on the PCB 20 are electrically conductive so that the conductive elastic body 41 and the like can be electrically contacted with the conductive elastic body 41 and the like even if a slight positional deviation occurs when the PCB 20 is assembled. It is formed larger by 1.0 mm than the bottom diameter of the elastic elastic body 41 and the like. In a preferred example, when the bottom diameter of the conductive elastic body 41 etc. is 3.0 mm, the diameter of the circumscribed circle of the contact electrode group 101 etc. is 4.0 mm.

  The metal domes 24, 28 and the like are fixed on the PCB 20 by covering one large adhesive sheet 130 from above. The adhesive sheet 130 is an insulating sheet. In this state, each contact electrode group 101 on the PCB 20 is also covered with the adhesive sheet 130 and cannot be electrically contacted with each conductive elastic body 41 or the like. An opening 140 is formed in the bottom. As a result, when a load F is applied to each conductive elastic body 41 etc. from above, each conductive elastic body 41 etc. can come into electrical contact with each contact electrode group 101 etc. through the opening 140. . The size of the opening 140 is formed in a circular shape having a diameter 0.5 mm smaller than a circumscribed circle of the contact electrode group 101 and the like in consideration of a deviation tolerance when being attached to the PCB 20. In a preferred example, when the diameter of the circumscribed circle of the contact electrode group 101 or the like is 4.0 mm, the diameter of the opening 140 is 3.0 mm. The two comb electrodes constituting the contact electrode group 101 and the like have 3 or 4 electrodes having a width of 0.15 mm, and are arranged so that the electrodes are separated by a pitch of 0.15 mm so that they do not contact each other. ing. The comb electrode has a form in which a copper foil is plated with gold.

  A total of twelve types of conductive elastic bodies 41, etc., each having two types of bottom surface diameters, each having a different tip end surface area, and a conductive elastic body having a spherical tip as a comparison, are used as the swing member 30. The performance evaluation was performed in a state in which the rocking member 30 was disposed above the PCB 20 having the structure shown in FIG. The performance evaluation items are an evaluation to see if it shows a stable and accurate direction at low load (stability at low load) and whether there is little sudden change in the relationship between the load and resistance (signal curve). Two types of evaluation (signal curve characteristics) were used.

  In the stability test at low load, it is “3” when the detection of the pressure exactly matches the operation direction at a load of 0.5 N or less. It was set to “2” when it was recognized that it was not enough, and was set to “1” when the detection of the pressure at the same load was inconsistent with the operation direction and was a concern during normal use. In the signal curve characteristics, “3” is displayed when there is no sudden drop in resistance over the entire load range, and “2” when there is a sudden drop in resistance over the low load range. Was marked as “1” when an extremely large drop was observed and it was a concern during normal use.

  Table 1 shows the results of performance evaluation tests when various conductive elastic bodies having a bottom diameter of 3.0 mm are used. Table 2 shows the results of a performance evaluation test when various conductive elastic bodies having a bottom diameter of 2.5 mm were used. Table 3 shows changes in resistance values of various conductive elastic bodies having a bottom surface diameter of 3.0 mm when the load is changed from 0.1 to 10N. FIG. 9 is a graph of the results in Table 3. The dotted line labeled “SR” in FIG. 9 indicates the data of the original conductive elastic body having a spherical tip.

  From the performance evaluation shown in Tables 1 to 3 and FIG. 9, when a conductive elastic body having a spherical tip is used, it is stable at low load regardless of whether the bottom diameter is 2.5 mm or 3.0 mm. There was a problem with sex. In particular, when the bottom diameter was 2.5 mm, the stability was lacking. On the other hand, when a conductive elastic body having a tip that is a horizontal plane is used, a conductive elastic body manufactured by cutting the tip at a position where the bottom diameter is 2.5 mm and X = 0.05 mm is used. In this case, although the stability at low load was “2”, there was no problem in the stability at low load in other conductive elastic bodies having a tip at a horizontal plane. On the other hand, in terms of signal curve characteristics, a conductive elastic body produced by cutting the tip at a position where the bottom diameter is 2.5 mm and X = 0.20 mm or more, and the bottom diameter is 3.0 mm and X = 0.25 mm or more. In the conductive elastic body produced by cutting the tip at the position, the performance was lower than other conductive elastic bodies. Among the conductive elastic bodies used for the evaluation, the conductive elastic body having a bottom diameter of 3 mm and X = 0.05 to 0.20 mm and the conductive elastic body having a bottom diameter of 2.5 mm and X = 0.10 to 0.15 mm The elastic elastic body was the most excellent, and all evaluation items were “3”.

  As shown in Table 3, in the case of a conductive elastic body having a bottom diameter of 3.0 mm, the electric resistance value is 2000 ohms or less when the load is 0.1 N, and the load is when the load is 0.5 N. Is a conductive elastic body (X = 0.05 mm, 0.10 mm, and 0.15 mm conductive elastic body) that maintains 50% or more of the electric resistance value when 0.1N, and has no sudden change in electric resistance. I found it excellent. Among these, it was found that the conductive elastic body with X = 0.05 mm is most preferable because the resistance value is gradually displaced.

  When the multi-directional switch member 2 is rotationally operated, even if the pressure on the track to be operated becomes weak, the horizontal surface at the tip of the conductive elastic body 41 or the like comes into contact with the contact electrode group 101 or the like immediately below the weak pressure. If designed in this way, a large fluctuation of the voltage value in each contact electrode group 101 or the like due to a fluctuation in pressing during a rotating operation does not occur. This is because even if the pressing force fluctuates, the size of the contact area in which the horizontal surface at the tip is in contact with the contact electrode group 101 directly below it does not vary greatly. On the other hand, in the case of the conductive elastic body 41 or the like having a spherical tip, if there is a change in the pressure on the rotating operation track, the conductive elastic body 41 or the like and the contact electrode group 101 or the like directly below the conductive elastic body 41 or the like. The contact area tends to fluctuate greatly. Due to this large fluctuation, a malfunction is likely to occur in the operation of detecting that the rotation operation is being performed. Therefore, when the display information displayed on the display unit 3 is more smoothly scrolled by the rotation operation of the multidirectional switch member 2, the voltage value in each contact electrode group 101 or the like hardly changes during the rotation operation. However, the conductive elastic body 41 in a horizontal plane is superior.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and can be implemented with various modifications.

  FIG. 10 is a diagram showing a modification of the PCB shown in FIG.

  As with the PCB 20 shown in FIG. 10, the contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108 may be arranged independently. In this case, in each of the contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108, the voltage value is individually measured and whether or not the voltage value has passed the threshold value is determined. When the PCB 20 as shown in FIG. 10 is used, the conductive elastic bodies 41, 42, 43, 44, 45, 46, 47, and 48 are not used, and even if the tip is spherical, the accuracy is somewhat accurate. The direction of pressing can be detected. In the case of the conductive elastic body 41 having a spherical tip, the eight contact electrode groups 101, 102, 103, and 104 tend to be unstable in the low load region, although they tend to be unstable. , 105, 106, 107, 108 are arranged in an independent manner, compared with the case where they are arranged so as to be integrated into four electrode bodies, the area handled by one contact electrode group 101, etc. This is because erroneous detection of the direction is less likely to occur. Furthermore, in addition to the method of specifying the direction from the above-described vector synthesis, the method of specifying the contact electrode group 101 having the smallest resistance value is also used in combination, thereby further increasing the probability of misdetection of the direction. Can also be reduced. However, as compared with a configuration in which eight contact electrode groups are integrated into four electrode bodies as in the PCB 20 shown in FIG. 6, a larger number of ports of a semiconductor chip functioning as a CPU are used. In the case where priority is given to reduction and simplification in circuit design, a configuration in which eight contact electrode groups are integrated into four electrode bodies as in PCB 20 shown in FIG. 6 is preferable.

  Further, a multi-directional switch member that can be operated not only by rotating but by swinging the outer periphery of the swing member 30 without arranging the rotation operation plate 70 above the swing member 30 may be used. The center key 50 is not necessarily provided. Even when the rotation operation plate 70 is provided, the rotation operation plate 70 may be directly disposed on the swing member 30 without providing the multidirectional operation plate 60. In that case, the friction reducing member 80 is preferably fixed to the front surface of the disk 33 of the swing member 30 or the inner top surface of the recess 71.

  The contact electrode groups 101, 102, 103, 104, 105, 106, 107, 108 need not be composed of comb-like electrodes. For example, the contact electrode group may be configured by bringing a plurality of semicircular shapes or a plurality of fan-shaped electrodes obtained by halving the semicircular shapes into a non-contact state.

  The present invention can be used for electronic devices, particularly small electronic devices.

1 Mobile phone (electronic equipment)
2 Multidirectional switch member 20 PCB (Printed Circuit Board)
30 Oscillating member (Oscillating member)
41, 42, 43, 44, 45, 46, 47, 48 Conductive elastic body 44a Horizontal plane (tip surface)
50 Center key 60 Multi-directional operation plate 70 Rotation operation plate 80 Friction reducing members 101, 102, 103, 104, 105, 106, 107, 108 Contact electrode group

Claims (5)

A swing member capable of swinging in the front and back direction at the outer peripheral portion in a plurality of directions from the center in the plane;
A printed circuit board disposed opposite to the swinging member in the back direction of the swinging member, and includes a plurality of electrodes at a position corresponding to the outer peripheral portion of the surface facing the swinging member. A printed circuit board having a plurality of contact electrode groups;
A plurality of conductive elastic bodies arranged to face the contact electrode group on the back surface of the swing member and to be along the circumferential direction of the swing member;
With
The multi-directional switch member, wherein the conductive elastic body has a portion whose horizontal cross section is reduced toward the contact electrode group, and a tip surface of the portion is a horizontal plane parallel to the contact electrode group.   The conductive elastic body has an electrical resistance value of 2000 ohms or less when the load from above is 0.1N, and the electrical resistance value when the load is 0.1N when the load from above is 0.5N. The multi-directional switch member according to claim 1, wherein 50% or more is maintained.   The multi-directional switch member according to claim 1, wherein the conductive elastic body is disposed at a position radially extending in eight directions from the center of the back surface of the swing member.   2. The rotary operation plate according to claim 1, further comprising a rotation operation plate capable of pressing the outer peripheral portion of the swing member in a front side direction of the swing member and capable of rotating in its own plane. Item 4. The multidirectional switch member according to any one of Items 3 to 3. A swing member capable of swinging in the front and back direction at the outer peripheral portion in a plurality of directions from the center in the plane;
A printed circuit board disposed opposite to the swinging member in the back direction of the swinging member, and includes a plurality of electrodes at a position corresponding to the outer peripheral portion of the surface facing the swinging member. A printed circuit board having a plurality of contact electrode groups;
The back surface of the swing member is opposed to the contact electrode group, and is disposed along the circumferential direction of the swing member, and has a portion whose horizontal cross section decreases toward the contact electrode group, and the portion One or a plurality of conductive elastic bodies whose tip surface is a horizontal plane parallel to the contact electrode group,
An electronic device comprising a multidirectional switch member comprising:

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