JP5255547B2 - Capacitive touchpad input device - Google Patents

Description

  The present invention relates to a capacitive touch pad input device that inputs a command to an external device according to a position touched by an object.

The capacitive touch pad input device is widely used, for example, as an input device for a personal computer, and in recent years, it is also used as an input device for a vehicle navigation system or the like.
The capacitive touch pad input device has a panel member, and an electrode group is disposed on the back side of the panel member. The electrode group includes, for example, an X electrode and a Y electrode as drive electrodes, and a detection electrode, and the drive electrode and the detection electrode are supported by a common or separate film substrate.

A printed circuit board is disposed on the back side of the film substrate, and the printed circuit board is provided with a control circuit for detecting the position of the object that has contacted the panel member in cooperation with the drive electrode and the detection electrode. .
Specifically, when a dielectric such as a finger touches the panel member, the capacitance between the drive electrode and the detection electrode changes, and an output corresponding to the change in capacitance is obtained from the detection electrode. Based on this output, the control circuit specifies the contact position of the dielectric on the panel member, and inputs a command corresponding to this position to an external device such as a personal computer.

  Further, some capacitive touch pad input devices have a metal shield member disposed between a film substrate and a printed circuit board (see, for example, Patent Document 1 and Patent Document 2). The shield member shields noise from the back side with respect to the drive electrode and the detection electrode, and thereby the detection of the position of contact of the object using the change in capacitance is favorably performed.

JP 2007-157107 A JP 2005-18138 A

Certainly, when a conductive shield member is disposed in the vicinity of the drive electrode and the detection electrode, noise from the back side is shielded, and the output background of the detection electrode is stabilized. From this viewpoint, the position detection accuracy of the capacitive touch pad input device is improved by the shield member.
However, when the conductive shield member is disposed in the vicinity of the drive electrode and the detection electrode, the capacitance between the drive electrode and the detection electrode is reduced, so that the output level of the detection electrode is reduced. A decrease in the output level of the detection electrode is not preferable from the viewpoint of improving the position detection accuracy.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a capacitive touch pad input device having excellent position detection accuracy in which a decrease in the output level of a detection electrode due to a conductive shield member disposed in the vicinity of a drive electrode and a detection electrode is suppressed. Is to provide.

According to one aspect of the present invention, a panel member having a surface as an operation surface, at least one electrode substrate supporting a drive electrode and a detection electrode respectively extending in parallel to the panel member, and extending in parallel to the electrode substrate. A conductive shield member, and a control circuit for detecting the approach of an object to the panel member based on a change in capacitance between the drive electrode and the detection electrode, the panel member, the electrode substrate, and The electrostatic capacity type touch pad input device in which the shield members are stacked in this order further includes a non-conductive spacer sandwiched between the electrode substrate and the shield member. capacitive touch pad input device is Ru are provided.

In the capacitive touch pad input device of one aspect, noise from the back side with respect to the drive electrode and the detection electrode is blocked by the shield member. For this reason, in this capacitive touch pad input device, the output background of the detection electrode is stable.
On the other hand, in this capacitive touch pad input device, the electrode substrate and the shield member are separated from each other due to the presence of the spacer. Thereby, the influence which a shield member has on the output level of a detection electrode is reduced, and the fall of the output level of a detection electrode, ie, a detection sensitivity, is suppressed.
As a result of these, this capacitive touch pad input device is excellent in object position detection accuracy, and thus excellent in operability.

Preferably, the electrode substrate is made of a flexible flexible substrate, the spacer is made of a cushion member having elasticity in the stacking direction of the panel member, the electrode substrate and the shield member, and the cushion member is wherein it is held in a compressed state in a stacking direction, wherein the electrode substrate, by the reaction force of compression of the cushion member, that is closely to the panel member.

In the capacitive touch pad input device according to a preferred embodiment, the electrode substrate is brought into close contact with the back surface of the panel member by the reaction force from the compressed spacer. In this case, there is no gap between the electrode substrate and the panel member, and there is substantially no low dielectric constant layer made of air between the electrode substrate and the panel member. For this reason, in this capacitive touch pad force device, the output of the detection electrode is further improved.
In this case, the distance in the stacking direction between the drive electrode and the detection electrode and the operation surface is constant over the entire operation surface. For this reason, even if the contact position of the object in the operation surface is different, the output level of the detection electrode is constant, and variations in detection sensitivity within the operation surface are suppressed.
As a result, this capacitive touch pad input device has even better object position detection accuracy.

Preferably, the cushion member is ing the expandable resin.
Since the foamable resin contains more air than the non-foamable resin, the dielectric constant of the foamable resin is lower than the dielectric constant of the non-foamable resin. In the capacitive touch pad input device according to the preferred embodiment, the decrease in the output level of the detection electrode is further suppressed due to the low dielectric constant of the spacer. As a result, this capacitive touch pad input device has even better object position detection accuracy.

Preferably, the shield member is installed on a side opposite to the electrode substrate, and is integrally connected to a control substrate on which the control circuit is mounted, and an outer edge of the panel member, and the electrode substrate, the shield member, the spacer, and A peripheral wall surrounding the control board; a stage disposed between the spacer and the control board; and a plurality of elastic pieces integrally formed on one of an outer edge of the stage and the peripheral wall so as to be elastically deformable. A plurality of engaging portions formed on the other of the outer edge of the stage and the peripheral wall and releasably engaged with the elastic piece, and when the elastic piece engages with the engaging portion, wherein said cushion member in between the electrode substrate and the shielding member is Ru is compressed.

  In the capacitive touch pad input device according to a preferred aspect, the elastic piece and the engaging portion are engaged with each other, so that the spacer is reliably held in a compressed state with a simple configuration.

Preferably, the panel member has a plurality of light-emitting portions having translucency, and the electrode substrate, the spacer, the shield member, and the stage each have an opening that overlaps the light-emitting portion when viewed in the stacking direction. It has, between the control board and the stage, the electrode substrate, the spacer, further Ru comprising a plurality of light emitting elements for irradiating respectively the light to the light emitting portion through the opening of the shield member and the stage.

  According to the capacitive touch pad input device of a preferred embodiment, the operability of the user is improved by the light emitting element irradiating light to the light emitting portion. For example, the user can confirm the position of the panel member by visually recognizing the light emitting unit. In addition, for example, characters, symbols, figures, etc. are drawn on the light emitting unit, and instructions are assigned to each light emitting unit in advance, so that various commands can be easily given to the capacitive touch pad input device. Can be entered.

On the other hand, when an opening is provided in the electrode substrate in order to guide light to the light emitting portion, the drive electrode and the detection electrode must be formed avoiding the opening. Here, when only the influence of the electrode substrate is considered, the light emitting portion of the panel member that overlaps the opening portion of the electrode substrate is compared with the non-light emitting portion of the panel member that overlaps the portion other than the opening portion of the electrode substrate. Output is low.
On the other hand, in the electrostatic capacitance type touchpad input device of a preferable aspect, the opening part is formed also in the shield board corresponding to the light emission part. Here, when only the influence of the shield member is considered, in the light emitting portion of the panel member that overlaps the opening of the shield plate, the detection electrode of the detection electrode is compared with the non-light emitting portion of the panel member that overlaps the portion other than the opening of the shield plate. Output increases.

As a result, the decrease in the output of the detection electrode at the light emitting portion due to the provision of the opening in the electrode substrate and the increase in the output of the detection electrode at the light emission portion due to the provision of the opening in the shield member seem to cancel each other. And the variation in the output of the detection electrode due to the position in the operation surface is suppressed.
In addition, according to this capacitive touch pad force device, light is emitted with a simple configuration by providing an opening in the stage and arranging a light emitting element between the stage and the control board. And the spacer is securely held in a compressed state.

  According to the present invention, there is provided a capacitive touch pad input device that suppresses a decrease in output of the detection electrode due to a conductive shield member disposed in the vicinity of the drive electrode and the detection electrode and has excellent position detection accuracy. The

1 is a schematic perspective view illustrating an arrangement of a capacitive touch pad input device according to a first embodiment on the front side of a vehicle compartment of a vehicle. FIG. 2 is a schematic perspective view of the capacitive touch pad input device of FIG. 1. FIG. 3 is a schematic exploded perspective view of the capacitive touch pad input device of FIG. 2. FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. 2. FIG. 3 is a schematic plan view of a film substrate used in the capacitive touch pad input device of FIG. 2. It is a schematic plan view which shows the other side of the film substrate of FIG. It is a block diagram which shows the electric circuit of the touchpad input device of FIG. It is a schematic exploded perspective view of the capacitive touch pad input device of the second embodiment. FIG. 9 is a schematic plan view of a film substrate used in the capacitive touch pad input device of FIG. 8. It is a schematic plan view which shows the other side of the film substrate of FIG. FIG. 9 is a schematic cross-sectional view taken along line XI-XI in FIG. 8.

  Hereinafter, a capacitive touch pad input device (hereinafter also simply referred to as a touch pad input device) 10 according to a first embodiment of the present invention will be described with reference to the drawings. In the drawings, in order to facilitate understanding of the configuration of the touchpad input device 10, the size and thickness of the members are appropriately changed.

FIG. 1 partially shows the front side of a vehicle compartment. The touch pad input device 10 has a function as an input device for a passenger to operate a navigation device, an air conditioner, an audio device, and the like. For this reason, the touch pad input device 10 is fixed at a position where an occupant can easily operate, for example, an appropriate position from the instrument panel 12 to the center console.
The touch pad input device 10 includes a panel member 14 and is embedded in the instrument panel 12 with the panel member 14 exposed, for example. The occupant can operate external devices such as a navigation device, an air conditioner, and an audio device by touching the surface of the panel member 14 as an operation surface.

  FIG. 2 is a schematic perspective view showing the appearance of the touchpad input device 10. The panel member 14 is made of a transparent or translucent resin, and as shown in FIG. 2, for example, a part of the housing 15 is integrally formed. The housing 15 has a box shape, that is, a hollow rectangular parallelepiped shape, and one surface of the housing 15 is open. The surface of the panel member 14 opposite to the opening is an operation surface.

Arbitrary characters, symbols, or figures may be directly drawn on the surface of the panel member 14, or a seal on which the characters, symbols, or figures are drawn may be attached. For example, in the present embodiment, black paint is applied to substantially the entire surface of the panel member 14 except for the six character 16 portions of “A”, “B”, “C”, “D”, “E”, and “F”. 17 is given. Six characters 16 are drawn by partially removing the black paint 17 by laser etching.
In the present specification, the coating or sealing applied to the surface of the panel member 14 is also regarded as a part of the surface of the panel member 14.

A peripheral wall 18 is integrally connected to each of the four edges of the panel member 14 at a right angle. A plurality of protrusions 20 are integrally formed on the outer surface of the peripheral wall 18, and screw holes 22 are respectively formed in the protrusions 20. The screw hole 22 is used to fix the touch pad input device 10 to the instrument panel 12 with a screw.
A plurality of engagement holes 24 are formed on the side of the peripheral wall 18 opposite to the panel member 14.

3 is an exploded perspective view schematically showing the touch pad input device 10, and FIG. 4 is a schematic sectional view taken along line IV-IV in FIG. 2 and 3, for convenience of explanation, the color of the character 16 on the panel member 14 and the color of the portion other than the character 16 are reversed.
As shown in FIGS. 3 and 4, the film substrate 30, the spacer 40, the shield plate 50, the holder 60, the first printed circuit board 70, and the second printed circuit board 80 are accommodated inside the housing 15. ing.

The film substrate 30 is made of an insulating resin sheet and has a rectangular outer diameter shape substantially equal to the shape of the panel member 14. The film substrate 30 has six rectangular openings 32 corresponding to the arrangement of the characters 16.
Further, the film substrate 30 is integrally provided with leads 33. The lead 33 has a rectangular shape and extends from the outer edge of the film substrate 30 to the second printed circuit board 80.

  Here, as shown in FIGS. 5 and 6, a plurality of drive electrodes 34 and one detection electrode 35 are integrally formed on the film substrate 30. In other words, the film substrate 30 supports the drive electrode 34 and the detection electrode 35. The drive electrode 34 and the detection electrode 35 extend over the entire area of the film substrate 30 in a predetermined pattern in order to detect the position of the object that has contacted the surface of the panel member 14.

More specifically, the detection electrode 35 has a substantially comb-tooth shape. However, the linear portion 35a corresponding to the comb teeth of the detection electrode 35 is provided with a plurality of orthogonal branch portions 35b and an angular C-shaped detour portion 35c surrounding the opening portion 32. Yes.
The drive electrode 34 includes a plurality of Y electrodes 36 and an X electrode 37. As shown in FIG. 5, the plurality of Y electrodes 36 are formed in the same layer as the detection electrode 35 on the film substrate 30. That is, the film substrate 30 has a multilayer structure.
The Y electrodes 36 are arranged between the straight portions 35a so as to mesh with the straight portions 35a of the detection electrodes 35, and extend in parallel with the straight portions 35a. Each of the Y electrodes 36 is also provided with a plurality of orthogonal branch portions 36b, and the branch portions 36b of the Y electrode 36 are arranged so as to mesh with the branch portions 35b of the detection electrode 35.

  The X electrode 37 is formed in a layer different from the detection electrode 35 and the Y electrode 36 on the film substrate 30, and extends in a direction orthogonal to the linear portion 35 a and the Y electrode 36 of the detection electrode 35. Therefore, the linear portion 35 a and the Y electrode 36 of the detection electrode 35 are separated from each other in the longitudinal direction of the X electrode 37. The X electrodes 37 are arranged avoiding the openings 32, and the X electrodes 37 are separated from each other in the longitudinal direction of the Y electrode 36.

A plurality of signal lines 38 are formed on the lead 33, and the signal line 38 connects the drive electrode 34 and the detection electrode 35 to a connector terminal 39 formed at the tip of the lead 33.
Since the film substrate 30 is transparent, the detection electrode 35, the Y electrode 36, and the X electrode 37 can be visually recognized on any surface. However, in order to avoid line complication, the X electrode 37 is not shown in FIG. The detection electrode 35 and the Y electrode 36 are omitted in FIG.

  Referring to FIGS. 3 and 4 again, the spacer 40 has a rectangular outer shape and has a predetermined thickness. The outer shape of the spacer 40 matches the outer shape of the film substrate 30, and six openings 42 are formed in the spacer 40 corresponding to the arrangement of the characters 16. In a state where the spacer 40 is overlaid on the film substrate 30, the opening 32 of the film substrate 30 is overlaid on the opening 42 of the spacer 40.

  The spacer 40 is non-conductive and is preferably made of a cushion member. The cushion member has elasticity in the thickness direction, in other words, in the stacking direction of the film substrate 30 and the spacer 40. As such a cushion member, a foamable resin is preferably used. In this embodiment, urethane foam is used, and although not shown, a PET film is pasted on one side of the urethane foam to maintain the form.

The shield plate 50 is made of a conductive plate, for example, a thin plate made of metal such as stainless steel. The outer shape of the shield plate 50 is rectangular and matches the outer shape of the film substrate 30 and the spacer 40. The shield plate 50 has six openings 52 corresponding to the arrangement of the characters 16. In a state where the shield plate 50 is overlaid on the spacer 40, the opening 52 of the shield plate 50 is overlaid on the opening 42 of the spacer 40.
The shield plate 50 is integrally connected with a connecting portion 53 bent into an L shape. The connecting portion 53 extends from the outer edge of the shield plate 50 to the first printed circuit board 70.

The holder 60 includes a stage 61 made of resin. The stage 61 has substantially the same rectangular outer shape as the shield plate 50, and the stage 61 has a plurality of openings 62 corresponding to the arrangement of the characters 16.
The openings 32, 42, 52, 62 overlap each other in the stacking direction of the film substrate 30, the spacer 40, the shield plate 50, and the stage 61, and have substantially the same contour, but the openings of the shield 50 plate The area 52 is slightly larger than the areas of the other openings 32, 42, 62.

  The holder 60 has a plurality of elastic pieces 63 formed integrally with the stage 61. The elastic piece 63 extends from the outer edge of the stage 61 toward the side opposite to the panel member 14 in the stacking direction. The distal end side of the elastic piece 63 is bent obliquely outward from the outer edge of the stage 61, and the distal end of the elastic piece 63 is received in the engagement hole 24 of the housing 15.

  When the holder 60 is disposed in the housing 15, the elastic piece 63 is pushed and elastically deformed by the peripheral wall 18 as the holder 60 is pushed from the opening of the housing 15 toward the panel member 14. And when the front-end | tip of the elastic piece 63 is received in the engagement hole 24, the elastic deformation of the elastic piece 63 is relieved. Thus, when the tip of the elastic piece 63 is received in the engagement hole 24, the tip of the elastic piece 63 engages with the engagement hole 24.

  Although the engagement between the tip of the elastic piece 63 and the engagement hole 24 can be released, the holder 60 cannot be pushed further into the housing 15 unless the engagement is released, and the holder 60 can be removed from the housing 15. It cannot be taken out. That is, the elastic piece 63 and the engagement hole 24 constitute fixing means for fixing the holder 60 to the housing 15.

Preferably, when the holder 60 is fixed to the housing 15 by the elastic piece 63 and the engagement hole 24, the spacer 40 is held in a compressed state in the stacking direction, and the panel member 14, the film substrate 30, The spacer 40, the shield plate 50, and the stage 61 are closely attached in the stacking direction without any gap. Thus, the length of the elastic piece 63 or the position of the engagement hole 24 in the stacking direction is appropriately set so that the spacer 40 is held in a compressed state.
In addition, the thickness of the spacer 40 in a free state is about 1.5 mm, and the thickness of the spacer 40 in a compressed state is about 1 mm.

The first printed circuit board 70 has a rectangular shape smaller than the stage 61, and on the stage 61 side of the first printed circuit board 70, there are six LEDs 71 as light emitting elements corresponding to the arrangement of the characters 16. Has been placed.
The LED 71 emits light toward the character 16 of the panel member 14 through the openings 62, 52, 42, and 32 that communicate with each other in the stacking direction. The panel member 14 is transparent or translucent, and the black paint 17 is removed in the character 16 portion. Therefore, when the LED 71 emits light, the character 16 floats on the surface of the panel member 14.
Note that when the LED 71 is off, the character in the panel member 14 is inconspicuous because the interior of the housing 15 is dark.

  The first printed circuit board 70 is formed with lands 72 that are electrically connected to the ground, and through holes 74 are opened in the lands 72. The land 72 cooperates with the stage 61 to sandwich the tip of the connecting portion 53 of the shield plate 50 in the stacking direction, and a through hole 54 is also formed at the tip of the connecting portion 53 so as to communicate with the through hole 74. ing. The stage 61 is formed with a screw hole 64 communicating with the through holes 54 and 74.

By screwing the screw 65 into the screw hole 64 through the through holes 54 and 74, the first printed circuit board 70 and the shield plate 50 are fixed to both sides of the stage 61 with the tip of the connecting portion 53 in close contact with the land 72. The
A plurality of claws 66 are integrally formed on the stage 61 on the first printed board 70 side, and the claws 66 engage with the outer edge of the first printed board 70, whereby the first printed board 70. Is more securely fixed to the stage 61.

  Furthermore, on the opposite side of the first printed circuit board 70 from the stage 61, an electrical component (not shown) constituting a lighting circuit for lighting the LED 71 and a connector 75 for connecting the lighting circuit to the outside are mounted. ing.

The second printed circuit board 80 has substantially the same rectangular shape as the first printed circuit board 70. However, the second printed circuit board 80 is formed with a notch that allows the lead 33 to pass therethrough.
A connector 81 to which the lead 33 is connected is mounted on the opposite side of the second printed board 80 from the first printed board 70. The second printed circuit board 80 includes an IC chip 82 that constitutes a position detection circuit or a control circuit for detecting the position of the object based on a change in capacitance between the drive electrode 34 and the detection electrode 35. The electrical parts are mounted. Furthermore, another connector 83 for connecting the touch pad input device 10 to an external device is mounted on the second printed circuit board 80 on the same side as the connector 81.

On the other hand, another connector 84 is mounted on the first printed circuit board 70 side of the second printed circuit board 80, and the connector 84 is connected to a connector 75 mounted on the first printed circuit board 70.
Through the connector 75 and the connector 84, the second printed circuit board 80 is not only supported by the first printed circuit board 70 but also connected to a position detection circuit and a lighting circuit.
Note that a plurality of support columns 67 are integrally provided on the stage 61 of the holder 60, and the support columns 67 extend in a direction opposite to the panel member 14 in the stacking direction. Each column 67 is in contact with the outer edge of the second printed circuit board 80, and the column 67 prevents the second printed circuit board 80 from being inclined with respect to the first printed circuit board 70.

FIG. 7 shows the configuration of the position detection circuit and the lighting circuit.
The position detection circuit includes a control unit 90, and the control unit 90 scans the voltage applied to the drive electrode 34.
On the other hand, the detection electrode 35 is connected to the control unit 90 via the amplification unit 92 and the A / D conversion unit 93. As an output from the detection electrode 35, a voltage corresponding to the capacitance between each of the drive electrodes 34 and the detection electrode 35 is obtained by the amplifying unit 92. The A / D conversion unit 93 digitizes the voltage obtained by the amplification unit 92 and inputs it to the control unit 90. The control unit 90 calculates the contact position of the object on the panel member 14 based on the input numerical value, and outputs a command to the external device based on the calculation result.
In addition, the control unit 90 lights the LED 71 via the LED lighting unit 94 constituting the lighting circuit.

Hereinafter, the touch pad input device 100 according to the second embodiment will be described with reference to the drawings.
In addition, about the component which has the same function as 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.
As shown in FIG. 8, no letters or the like are drawn on the surface of the panel member 14, and a black paint 17 is applied to the entire surface. That is, the touch pad input device 100 does not have a highlighting function for characters and the like by the light emitting elements, and thus does not have the first printed circuit board 70.

9 and 10 show the film substrate 110 deployed inside the housing 15 in an expanded manner. The film substrate 110 is not formed with an opening, and leads 112 are integrally connected.
A driving electrode 114 and a detection electrode 115 are integrally formed on the film substrate 110, and the driving electrode 114 includes a Y electrode 116 and an X electrode 117. Since no opening is formed, the detection electrode 115 is not provided with a detour and a branch, and the drive electrode Y electrode 116 is also not provided with a branch.
A ground electrode 118 is integrally formed on the film substrate 110 so as to surround the X electrode 117 along the outer edge. The ground electrode 118 is electrically connected to the ground via the signal line 38 and the connector terminal 39.

  Another film substrate 120 is integrally connected to the lead 112 via two L-shaped bent portions 119. The film substrate 120 has a rectangular shape substantially the same size as the film substrate 110, and the conductive shield layer 121 is integrally formed on the film substrate 120 over almost the entire area. The bent portion 119 is formed with a metal layer 122 integrally connected to the shield layer 121, and the metal layer 122 is electrically connected to the ground via the signal line 38 and the connector terminal 39. Therefore, the shield layer 121 is also electrically connected to the ground.

As shown in FIG. 10, when in the state of being disposed in the housing 15, the film substrates 110 and 120 overlap with the compressed spacer 40 interposed therebetween. Therefore, the shield layer 121 has the same function as the shield plate 50.
In the second embodiment, no opening is formed in the spacer 40, the film substrate 120, and the stage 61. The second printed circuit board 80 is fixed to the holder 60 by a fixing member such as a screw (not shown).

  The capacitive touch pad input devices 10 and 100 of the first embodiment and the second embodiment described above each include a shield plate 50 and a shield layer 121 as shield members. The shield member extends in parallel to the film substrate 30 and blocks noise from the back side of the drive electrodes 34 and 114 and the detection electrodes 35 and 115, that is, from the first printed circuit board 70 and the second printed circuit board 80 side. . For this reason, in the touchpad input devices 10 and 100, the output background of the detection electrodes 35 and 115 is stabilized.

On the other hand, in the touch pad input devices 10 and 100, the film substrates 30 and 110 and the shield member are separated from each other due to the presence of the spacer 40. As a result, the influence of the shield member on the output levels of the detection electrodes 35 and 115 is reduced, and the output level of the detection electrodes 35 and 115, that is, the decrease in detection sensitivity is suppressed.
As a result of these, the touchpad input devices 10 and 100 are excellent in object position detection accuracy.

  In the touch pad input devices 10 and 100 according to the first and second embodiments described above, the film substrates 30 and 110 are brought into close contact with the back surface of the panel member 14 by the reaction force from the compressed spacer 40. In this case, there is no gap between the film substrates 30 and 110 and the panel member 14, and there is substantially no low dielectric constant layer made of air between the film substrates 30 and 110 and the panel member 14. For this reason, in this capacitive touch pad, the output of the detection electrodes 35 and 115 is further improved.

In this case, the distance in the stacking direction between the drive electrodes 34 and 114 and the detection electrodes 35 and 115 and the operation surface is constant over the entire operation surface. For this reason, even if the contact position of the object in the surface of the operation surface is different, the output levels of the detection electrodes 35 and 115 are constant, and variation in detection sensitivity in the operation surface is suppressed.
As a result of these, the touchpad input devices 10 and 100 have better object position detection accuracy.

  In the touch pad input devices 10 and 100 of the first and second embodiments described above, the spacer 40 is made of a foamable resin. Since the foamable resin contains more air than the non-foamable resin, the dielectric constant of the foamable resin is lower than the dielectric constant of the non-foamable resin. Since the dielectric constant of the spacer 40 is low, a decrease in the output level of the detection electrodes 35 and 115 is further suppressed. As a result, the touch pad input devices 10 and 100 have better object position detection accuracy.

  In the touch pad input devices 10 and 100 according to the first embodiment and the second embodiment described above, the spacer 40 is compressed with a simple configuration by the elastic piece 63 and the engagement hole 24 engaging with each other. It is securely held in the state.

According to the touch pad input device 10 according to the first embodiment described above, the LED 71 as the light emitting element irradiates the character 16 as the light emitting unit with light, thereby improving the operability for the user. For example, the user can confirm the position of the operation surface by visually recognizing the light emitting unit. Furthermore, for example, by assigning a command in advance for each light emitting unit, the user can easily input various commands to the touch pad input device 10.
On the other hand, when the opening 32 is provided in the film substrate 30 in order to guide light to the light emitting part, the drive electrode 34 and the detection electrode 35 must be formed avoiding the opening 32. Here, when only the influence of the film substrate 30 is considered, in the light emitting portion of the panel member 14 that overlaps the opening 32 of the film substrate 30, the non-light emitting portion of the panel member 14 that overlaps a portion other than the opening 32 of the film substrate 30. As compared with the output, the output of the detection electrode 35 becomes lower.

On the other hand, in the touch pad input device 10, an opening 52 is formed in the shield plate 50 corresponding to the light emitting part. Here, when only the influence of the shield plate 50 is considered, the light emitting portion of the panel member 14 that overlaps the opening portion of the shield plate is compared with the non-light emitting portion of the panel member 14 that overlaps the portion other than the opening portion of the shield plate 50. The outputs of the detection electrodes 35 and 115 are increased.
As a result, the output of the detection electrode 35 at the light emitting portion is reduced due to the opening 32 provided in the film substrate 30 and the output of the detection electrode 35 at the light emitting portion due to the opening 52 provided in the shield plate 50. It acts so as to cancel out the rise, and the variation in the output of the detection electrode 35 due to the position in the operation surface is suppressed.

  In addition, according to the touchpad input device 10, the opening 61 is also provided in the stage 61, and the LED 71 is disposed between the stage 61 and the second printed circuit board 80, so that the light can be emitted with a simple configuration. Is guided to the character 16 as the light emitting portion, and the spacer 40 is securely held in a compressed state.

The present invention is not limited to the first embodiment and the second embodiment described above, and includes forms in which various modifications are made to the first embodiment and the second embodiment without departing from the scope of the claims.
For example, the patterns of the drive electrodes 34 and 114 and the detection electrodes 35 and 115 are not limited to the first embodiment and the second embodiment. In addition, the drive electrodes 34 and 114 and the detection electrodes 35 and 115 are formed on one film substrate 30 and 110, but may be formed separately on two or more film substrates.

  In the first embodiment and the second embodiment described above, the elastic piece 63 is formed integrally with the stage 61. However, the elastic piece may be formed by forming a slit in the peripheral wall 18 of the housing 15. Further, although the tip of the elastic piece 63 is received in the engagement hole 24, an engagement hole is formed in the tip of the elastic piece 63, and the peripheral wall 18 of the housing 15 is received by the engagement hole of the elastic piece 63. Protruding protrusions may be formed.

  In the first embodiment and the second embodiment described above, the touch pad input devices 10 and 100 are used for operations of a vehicle navigation device, an air conditioner, an audio device, and the like. 100 can also be applied to an input device for a device other than a vehicle-mounted device. For example, the touch pad input devices 10 and 100 can be applied to devices such as a personal computer, a vending machine, an automatic teller machine (ATM), a portable device, or a remote controller capable of remotely operating a television receiver. It is.

10,100 Capacitive touch pad input device 14 Panel member 15 Housing 16 Character (light emitting part)
17 Black paint 18 Peripheral wall 24 Engagement hole (engagement part)
30 Film substrate (electrode substrate)
32 Opening of film substrate 33 Lead 34, 114 Drive electrode 35, 115 Detection electrode 36, 116 Y electrode 37, 117 X electrode 40 Spacer 42 Spacer opening 50 Shield plate (shield member)
52 Shield Plate Opening 60 Holder 61 Stage 62 Stage Opening 63 Elastic Piece 70 First Printed Circuit Board 71 LED (Light Emitting Element)
80 Second printed circuit board (control board)
120 Film substrate 121 Shield layer (shield member)

Claims (4)

A panel member having a surface as an operation surface, at least one electrode substrate supporting a drive electrode and a detection electrode respectively extending parallel to the panel member, a conductive shield member extending parallel to the electrode substrate, and A control circuit for detecting the approach of an object to the surface of the panel member based on a change in capacitance between the drive electrode and the detection electrode is provided, and the panel member, the electrode substrate, and the shield member are arranged in this order. In the laminated capacitive touchpad input device,
Further example Bei nonconductive spacer sandwiched between the electrode substrate and the shield member,
The electrode substrate comprises a flexible substrate having flexibility,
The spacer comprises a cushion member having elasticity in the stacking direction of the panel member, the electrode substrate and the shield member,
The cushion member is held in a compressed state in the stacking direction,
The capacitive touch pad input device , wherein the electrode substrate is in close contact with the panel member by a reaction force of compression of the cushion member . The capacitance type Dutch pad input device according to claim 1, wherein the cushion member is made of a foamable resin. A control board mounted on the side opposite to the electrode substrate with respect to the shield member, on which the control circuit is mounted;
A peripheral wall integrally connected to an outer edge of the panel member, and surrounding the electrode substrate, the shield member, the spacer, and the control substrate;
A stage disposed between the spacer and the control board;
A plurality of elastic pieces integrally formed on one of the outer edge of the stage and the peripheral wall so as to be elastically deformable;
A plurality of engaging portions formed on the other of the outer edge of the stage and the peripheral wall and releasably engaged with the elastic piece;
When the elastic piece is engaged with the engaging portion, the electrostatic capacitance according to claim 1 or 2, wherein the cushion member in between the shield member and the electrode substrate is characterized in that it is compressed Type Dutch pad input device. The panel member has a plurality of light emitting parts having translucency,
The electrode substrate, the spacer, the shield member, and the stage each have an opening that overlaps the light emitting portion when viewed in the stacking direction,
A plurality of light emitting elements that respectively irradiate light to the light emitting part through the opening of the electrode substrate, the spacer, the shield member, and the stage are further provided between the stage and the control substrate. Item 4. The capacitive touch pad input device according to Item 3 .

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