JP2011237916A - Electrostatic capacitance-type pointing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic capacitance-type pointing device that accurately detects a sliding direction and a sliding amount by reducing an influence of an electrostatic capacity change resulting from a finger functioning as conductive material.SOLUTION: In an electrostatic capacitance-type pointing device 11 that detects an electrostatic capacity change between an upper electrode 13b and an lower electrodes 12a by sliding an operation member 13 having the upper electrode 13b against a fixed member 12 having the lower electrodes 12a, the operation member 13 includes an operation part constituted by a key top 13c and the upper electrode 13b in the surrounding area thereof. The fixed member 12 includes a plurality of the divided lower electrodes 12a formed by roundly cutting out a circular portion around the center thereof. Therefore, a finger is not likely to overlap the upper electrode 13b or lower electrodes 12a so that the influence of the finger on the upper electrode 13b or lower electrodes 12a is reduced.

Description

  The present invention relates to a pointing device for slide operation used in various electronic devices such as a portable information terminal such as a mobile phone and a PDA, a remote controller, an AV device, and a game machine, and in particular, between both electrodes on the operation side and the fixed side. The present invention relates to a capacitance-type pointing device that detects a change in capacitance.

  Various electronic devices are becoming more and more functional year by year, and not only a single function selection but also an input operation using a switch, a display screen switching operation and a cursor moving operation on the display screen are performed. That is, not only a simple pressing operation, but also a 360 ° sliding operation in a direction intersecting the pressing operation direction has been performed. As a switch for performing the sliding operation, there is a pointing device that detects a moving direction and a moving distance of the sliding operation based on a change in capacitance or a change in magnetism. Among these pointing devices, the capacitance type that detects changes in capacitance between electrodes can be made thinner than the magnetic type that detects changes in magnetism with a magnet and a Hall element. It has not been.

  Such a capacitance-type pointing device includes, for example, a circular upper electrode, a lower electrode divided into four parts, as described in JP-A-7-49325 and JP-A-7-84718. Are provided and opposed to the upper substrate and the lower substrate, respectively. Then, when the operator slides the upper substrate provided with the upper electrode horizontally with a finger, the overlapping portion of the upper electrode and the lower electrode in the thickness direction of the pointing device changes, and the upper electrode and each of the lower parts divided into four parts are changed. The capacitance generated between the electrodes changes. The movement direction (slide direction) and the movement distance (slide amount) of the upper substrate are detected from the amount of change in capacitance.

Japanese Patent Laid-Open No. 7-49325 Japanese Patent Laid-Open No. 7-84718

By the way, since the operator's finger is also a kind of conductor, the capacitance generated between the upper electrode and the lower electrode is changed by the finger that is slid, and the sliding direction and the sliding amount of the upper substrate that has been slid are changed. There is a problem that it is difficult to detect accurately.
In order to reduce the influence of the capacitance due to such a finger, there is a method in which the operation surface side of the upper electrode (upper substrate) is covered with a conductive layer, and this conductive layer is connected to the ground to form a shield layer. However, it is difficult to always connect the sliding conductive layer to the ground. Furthermore, since the overlapping portion of the conductive layer and the lower electrode that slide is operated as a sensor, it is difficult to accurately detect the slide direction and the slide amount, and the practicality is poor.

  The present invention has been made against the background of the prior art as described above. That is, an object of the present invention is to provide a technique for accurately detecting a slide direction and a slide amount by reducing the influence of a finger as a conductor while being a thin slide operation switch.

In order to achieve the above object, the following configuration is provided.
That is, for the capacitive pointing device that detects a change in capacitance between the upper electrode and the lower electrode by sliding the operating member having the upper electrode relative to the fixing member having the lower electrode, the operating member is Capacitance characterized by comprising an operation part made of a key top and an upper electrode around the operation part, and the fixing member has a lower electrode formed by dividing the central part into a circular shape and being divided into a plurality of parts. A type pointing device is provided.

For a capacitive pointing device that detects a change in capacitance between an upper electrode and a lower electrode by sliding an operating member having an upper electrode relative to a fixed member having a lower electrode, the operating member is a key top The upper electrode is separated from the key top that is touched by a finger for a slide operation. Therefore, the influence of a finger as a conductor when detecting a change in capacitance can be reduced.
In addition, for the capacitive pointing device that detects a change in capacitance between the upper electrode and the lower electrode by sliding the operation member having the upper electrode relative to the fixed member having the lower electrode, the fixing member is Since the center electrode is provided with a lower electrode that is cut into a circular shape and divided into a plurality of parts, the lower electrode has a center portion that projects the center of the key top that the finger touches for sliding operation toward the lower electrode. It lacks and does not exist. Therefore, the influence of a finger as a conductor when detecting a change in capacitance can be reduced.
In other words, the lower electrode can be formed in an intermittent annular shape with a circular notch formed in the center, and in this way, the finger and the lower electrode in the overlapping direction of the upper electrode and the lower electrode. Can be eliminated or reduced, and the influence of the finger on the lower electrode can be reduced.
Since the upper electrode and the lower electrode are provided, it is possible to accurately detect the sliding direction and the sliding amount of the operation unit that has been slid.
Further, since the upper electrode is provided around the operation portion, the center portion has a notch shape. For this reason, if the key top is made translucent, light from an illumination light source provided on the fixed member side can be incident on the key top through the central portion (notch) of the upper electrode, and an illuminated key top is obtained. It is also possible.

  In this pointing device, the upper electrode is made of a conductive rubber-like elastic body, and the operation member is a capacitive pointing device that further includes a slide sheet that covers the lower side of the upper electrode and faces the lower electrode. Can do.

Since the upper electrode is made of a conductive rubber-like elastic body, a part of the shape of the operation member itself can be made of a conductive rubber-like elastic body. Therefore, the upper electrode can bear a part of the shape of the operation member, and the upper electrode made of a metal plate is fixed to the operation member or the conductive ink is printed, and the operation member is separately provided. There is no need to provide an upper electrode. Therefore, the number of parts can be reduced and the manufacturing process can be shortened.
Further, since the upper electrode is formed of a rubber-like elastic body, the upper electrode can be formed with an appropriate thickness as compared with a case where the upper electrode is formed of conductive ink. By forming a suitable thickness and providing a space in the center of the upper electrode, non-conductivity between the lower electrode and the finger is increased, and the influence of the finger on the lower electrode can be reduced.
Further, since the operation member further includes a slide sheet that covers the lower side of the upper electrode and faces the lower electrode, friction between the operation member and the fixing member can be reduced during the slide operation, and the slide operation load can be reduced. can do. Accordingly, a smooth slide operation can be realized, and the operator can obtain a good slide operation feeling.
Moreover, by providing a slide sheet on the back surface of the upper electrode made of a rubber-like elastic body, it is possible to suppress bending and deformation of the upper electrode during a slide operation. By forming the upper electrode with a rubber-like elastic body, if the external electrode comes into contact with other members, the frictional resistance will increase, causing the problem that it will be difficult to produce an accurate change in capacitance due to bending and deformation. By providing this, it is possible to prevent the external electrode from coming into direct contact with other members and improve the slidability and to make it difficult to deform the external electrode due to the rigidity of the slide sheet.

  In the capacitance-type pointing device, the operation member further includes a bellows-like bellows portion connected to the upper electrode and a fixing portion that is fixed to an exterior member positioned outside the key top, and is fixed to the bellows portion. And the upper electrode may be integrally formed of a conductive rubber-like elastic body.

Since the operation member is provided with the bellows-like bellows portion connected to the upper electrode, the operation member can be returned to the initial position by the biasing force of the bellows portion by releasing the finger after the bellows portion is deformed by the slide operation.
Since the operation member is provided with the fixing portion that is fixed to the exterior member located outside the key top, the operation member can be secured to the exterior member. As a result, the operation member that slides can be fixed to the electronic device, and the initial position when the slide operation is not performed can be determined.
And since the bellows part, the fixing | fixed part, and also the upper electrode were integrally formed with the electroconductive rubber-like elastic body, it can earth | ground through the exterior member to which a fixing | fixed part adheres. Therefore, the capacitance generated between the upper electrode and the lower electrode can be stabilized.

Moreover, it can be set as the electrostatic capacitance type pointing device in which an operation member is provided with the metal plate which hold | maintains the shape of the said fixing | fixed part.
Since the operation member includes a metal plate that retains the shape of the fixed portion, the shape of the operation member to be thinned can be stably retained.
In addition, by holding the shape of the fixed part, it is possible to prevent unexpected deformation of the fixed part during the slide operation and to leave the deformation to the bellows part, giving the operator a uniform feeling of sliding operation can do. In addition, it is possible to prevent the bellows part from being deformed more than necessary toward the fixed part, and to easily return the bellows part deformed by the slide operation to the original shape. Therefore, the operation unit after the slide operation can be easily returned to the initial position, and the repeated slide operation can be accurately detected.
Furthermore, it is possible to provide a ground between the circuit board and the exterior member through the metal plate, and the electrostatic capacitance generated between the upper electrode and the lower electrode can be stabilized.

The operation member may be a capacitive pointing device further including a disc spring between the key top and the slide sheet, and the fixing member further including a pressing detection electrode in the center of the lower electrode.
Since the operation member is provided with a disc spring between the key top and the slide sheet, and the fixing member is provided with a pressing detection electrode in the center of the lower electrode, the key top is separated from the detection of the slide amount. It is possible to provide a function of detecting the presence or absence of a pressing operation (pressing operation).
In other words, the distance between the disc spring and the press detection electrode when the key top is not pressed and the distance between the buckled disc spring and the press detection electrode when the key top is pressed are static due to the difference between the two. A change in electric capacity can be detected, and a key top pressing operation can be detected.
Further, since the disc spring is provided on the operation member, the disc spring slides along with the slide operation, so that the disc spring can be buckled by pressing at any position where the slide operation is performed. Therefore, when a disc spring is provided on the fixed member side, it is superior in that the press operation can be detected at any position where the slide operation is performed, compared to a structure in which the press operation can be detected only at a position where the disc spring is located. . Further, the operation member can be slid while being pressed, and so-called drag operation can also be realized.

The spread area (size) of the press detection electrode is preferably formed so as to overlap the disc spring at the pressed position even after the key top is slid. Depending on the slide movement position of the key top, if there is no pressing detection electrode at the pressing position during the sliding operation, the capacitance change varies greatly depending on the presence or absence of the pressing detection electrode. Because it becomes difficult.
When the size of the press detection electrode covers all the slide operation positions, the finger, the disc spring, and the press detection electrode overlap during the slide operation. The capacitance generated by the finger changes depending on the finger, but since the gap between the disc spring and the pressing detection electrode is small and the capacitance changes greatly due to the buckling of the disc spring, it affects the detection of the pressing operation. There are few.
The disc spring is preferably a metal disc spring whose entire portion can be a conductive portion, but a resin disc spring made of resin can also be used. In the case of a resin disc spring, a conductive portion may be fixedly provided at the center. Moreover, it can replace with the electroconductive part provided in a resin disc spring by providing an electroconductive part in a keytop.

Furthermore, it is possible to provide a capacitive pointing device in which a through hole is provided in the slide sheet at a portion facing the center of the disc spring, and a through hole electrode is provided in the through hole.
The slide sheet has a through-hole in the part facing the center of the disc spring, and the through-hole electrode is provided in the through-hole. The apparent gap between the electrode for use and the disc spring can be reduced by the thickness of the slide sheet.
In other words, when the through-hole electrode is provided, the amount of change in the capacitance between the disc spring and the pressing detection electrode before and after the pressing operation can be greatly changed, and the presence or absence of the key top pressing operation can be detected. Can be made easier.

  According to the capacitive pointing device of the present invention, it is possible to suppress a decrease in slide detection accuracy caused by recognizing an operator's finger as a conductor, and to accurately detect a slide direction and a slide amount by a slide operation. .

The top view which shows the electrostatic capacitance type pointing device of 1st Embodiment. FIG. 3 is a sectional view taken along line SA-SA in FIG. 1. Explanatory drawing which shows the lower electrode in the electrostatic capacitance type pointing device of 1st Embodiment. Explanatory drawing which shows the upper electrode in the electrostatic capacitance type pointing device of 1st Embodiment. FIG. 2 is a cross-sectional view corresponding to FIG. 2, illustrating a capacitive pointing device according to a second embodiment. Explanatory drawing which shows the lower electrode in the electrostatic capacitance type pointing device of 2nd Embodiment. Explanatory drawing which shows the modification of the lower electrode in the electrostatic capacitance type pointing device of 2nd Embodiment. FIG. 2 is a cross-sectional view corresponding to FIG. 2 illustrating a capacitive pointing device according to a third embodiment. FIG. 2 is a cross-sectional view corresponding to FIG. 2, illustrating a capacitive pointing device according to a fourth embodiment. FIG. 2 is a cross-sectional view corresponding to FIG. 2, illustrating a modification of the capacitive pointing device common to the embodiments.

  The present invention will be described in more detail with reference to the drawings. In addition, about the structure which is common in each embodiment, the same code | symbol is attached | subjected and duplication description is abbreviate | omitted and duplication description is also abbreviate | omitted also about a common material, an effect | action, an effect, a manufacturing method, etc.

First Embodiment (FIGS. 1 to 4) :
A capacitive pointing device 11 of the first embodiment is shown in FIGS. 1 is a plan view of the capacitive pointing device 11, FIG. 2 is a sectional view taken along the line SA-SA of the capacitive pointing device 11, and FIG. 3 is an explanatory diagram of a lower electrode in the capacitive pointing device 11. 4 is an explanatory diagram of the upper electrode in the capacitive pointing device 11. FIG.
The capacitive pointing device 11 according to the present embodiment includes a fixing member 12, an operation member 13, and a top cover 14.

  The fixing member 12 is a portion serving as a base of the capacitive pointing device 11 and is fixed in the electronic apparatus. In the present embodiment, the “circuit board” including the lower electrode 12 a and the pressing detection electrode 12 b is the fixing member 12.

  The lower electrode 12a is an electrode that generates a capacitance with an upper electrode 13b of the operation member 13 described later, and the capacitance changes when the upper electrode 13b of the operation member 13 slides. As shown in FIG. 3, the lower electrode 12a has an intermittent annular shape in which the central angle is divided into four at 90 °, and the central portion is cut into a circular shape. The outer diameter of the annular shape of the lower electrode 12a is larger than the inner diameter of the upper electrode 13b, that is, the overlapping direction of the upper electrode 13b and the lower electrode 12a, in other words, the operating member when the capacitive pointing device is viewed in plan view. The lower electrode 12a is sized to be covered by the upper electrode 13b in terms of projection onto the fixing member (the same applies hereinafter). Further, the inner diameter of the lower electrode 12a is slightly larger than the outer diameter of the key top 13c in the operation member 13, and is formed so as not to overlap the key top 13c in projection. In FIG. 3, the upper electrode 13b is indicated by a two-dot chain line.

The pressing detection electrode 12b is an electrode that generates a capacitance with the metal disc spring 13e of the operating member 13, and the capacitance changes when the operating portion 13c is pressed. As shown in FIG. 3, the pressing detection electrode 12b is located in a circular cutout formed at the center of the lower electrode 12a and is formed in a circular shape. The circular outer diameter of the pressing detection electrode 12b is larger than the outer diameter of the metal disc spring 13e and overlaps with the metal disc spring 13e on projection, and when the operation unit 13c slides, the metal disc It is formed in a size that overlaps with the spring 13e. In FIG. 3, the metal disc spring 13e is indicated by a two-dot chain line.
The lower electrode 12a and the pressing detection electrode 12b are made of conductive ink, metal, or the like.

  The operation member 13 is a member that inputs a sliding direction and a sliding amount of the capacitive pointing device 11, and is a member that can also be pressed in the present embodiment. The operation member 13 includes a slide sheet 13a, an upper electrode 13b, a key top 13c as an “operation unit”, a fixed sheet 13d for fixing the key top 13c, a metal disc spring 13e, a bellows portion 13f and a bellows outside the upper electrode 13b. A fixing portion 13g is provided outside the portion 13f.

The slide sheet 13a is a member that contacts the lower electrode 12a and the pressing detection electrode 12b on the circuit board 12 and rubs on the lower electrode 12a and the pressing detection electrode 12b when the key top 13c is slid. It is formed in a disk shape by a resin film. On the operation surface side of the slide sheet 13a, an upper electrode 13b is fixed to the outer edge side, and a metal disc spring 13g is curved and fixed to the operation surface side at the center.
As described above, the upper electrode 13b is an electrode that generates a capacitance with the lower electrode 12a. When the key top 13c is slid, the upper electrode 13b moves together with the key top 13c to change the capacitance. The upper electrode 13b is made of a conductive rubber-like elastic body, and is formed in an annular shape around the key top 13c separately from the key top. The slide sheet 13a is fixed by integral molding so that air does not enter the fixing surface. In FIG. 4, the arrangement of the circuit board 12, the lower electrode 12a, and the press detection electrode 12b with respect to the upper electrode 13b is indicated by a two-dot chain line.

The key top 13c is an “operation unit” that is touched with a finger during a slide operation or a pressing operation, and is formed in a disk shape with a hard resin. An annular rib 13h is provided on the operation surface side of the key top 13c so that an operator's finger is difficult to slide during a slide operation, and a pusher portion 13k that presses the metal disc spring 13e during a pressing operation on the back surface side. Is provided. A fixing sheet 13d is fixed to the back side of the key top 13c so as to penetrate the pusher portion 13k. The center of the disk-shaped key top 13c is disposed on the axis of the upper electrode 13b.
The fixed sheet 13d is a member that integrates the key top 13c with the upper electrode 13b, and is formed in an annular shape by a resin film. As described above, the pressing portion 13k of the key top 13c passes through the center of the fixing sheet 13d, and the outer edge is fixed to the upper electrode 13b via the double-sided tape 13m.
As described above, the metal disc spring 13e is an electrode that generates a capacitance with the pressing detection electrode 12b. When the key top 13c is pressed, the metal disc spring 13e is pressed by the pusher portion 13k, buckles, and the distance between the center of the metal disc spring 13e and the press detection electrode 12b approaches and the capacitance changes. . As shown in FIG. 4, the metal disc spring 13e is disposed at the center on the inner side of the upper electrode 13b.

The bellows portion 13f is a portion that returns the slid key top 13c to the initial position, and is formed in a bellows shape that extends circumferentially around the outer side of the upper electrode 13b by a rubber-like elastic body.
The fixing portion 13g is a portion that fixes the operation member 13 to the top cover 14, and is formed outside the bellows portion 13f by a rubber-like elastic body. The operation surface side of the fixing portion 13g is fixed to the back surface of the top cover 14 via a double-sided tape 13m. In the present embodiment, the upper electrode 13b, the bellows portion 13f, and the fixing portion 13g are integrally formed of a conductive rubber-like elastic body.

A thermosetting elastomer or a thermoplastic elastomer can be used as the material of the rubber-like elastic body that forms the upper electrode 13b, the bellows portion 13f, and the fixing portion 13g. Of these, silicone rubber having a low temperature dependency and a high resilience is preferable.
As the material of the resin film forming the slide sheet 13a and the fixed sheet 13d, a resin having heat resistance and rigidity is used. Among these, a polyethylene terephthalate (PET) resin film, a polyethylene naphthalate (PEN) resin film, a polycarbonate (PC) resin film, and the like are preferable.
As the material of the key top 13c, a hard resin such as polycarbonate (PC) resin that can be integrally formed with the fixing sheet 13d, or a metal such as stainless steel, aluminum, or brass can be used. In the present embodiment, a space is formed between the key top 13c and the lower electrode 12a by the upper electrode 13b made of a rubber-like elastic body, and the key top 13c and the lower electrode 12a do not overlap with each other on the projection. The body metal can be used as the key top 13c.

  The top cover 14 is an “exterior member” that covers the operation surface side of the circuit board 12 in the capacitive pointing device 11. The top cover 14 is made of a resin film, and a circular through hole 14a is formed through which the key top 13c of the operation member 13 is exposed.

An example of a method for manufacturing the capacitive pointing device 11 will be described.
First, an adhesive layer is formed on the outer edge side of the disc-shaped slide sheet 13a. The slide sheet 13a is inserted into a mold for molding the upper electrode 13b, the bellows part 13f, and the fixing part 13g, and then a conductive rubber composition is introduced to the slide sheet 13a, the upper electrode 13b, and the bellows part 13f. And the fixing portion 13g are integrally formed. Thereafter, the metal disc spring 13e is fixed to the slide sheet 13a, and a double-sided tape 13m is adhered to the operation surface side of the upper electrode 13b and the fixing portion 13g. Next, after inserting the annular fixed sheet 13d into a mold for forming the key top 13c, the key top 13c is formed, and the fixed sheet 13d and the key top 13c are integrally formed. Then, the fixing sheet 13d is attached to the double-sided tape 13m of the upper electrode 13b, and the operation member 13 is obtained.
Then, the double-sided tape 13 m of the fixing portion 13 g in the operation member 13 is attached to the top cover 14. Thereafter, the top cover 14 integrated with the operation member 13 and the circuit board 12 provided with the lower electrode 12a and the pressing detection electrode 12b are assembled to obtain the capacitive pointing device 11.

Since neither the upper electrode 13b nor the lower electrode 12a exists at the position corresponding to the center of the key top, even if the key top 13c is touched with a finger, the influence of the finger on the upper electrode 13b and the lower electrode 12a can be reduced. Therefore, it is possible to accurately detect the sliding direction and sliding amount of the key top 13c that has been slid.
According to the capacitance type pointing device 11, since the slide sheet 13a is provided on the back side of the operation member 13, friction with the circuit board 12 provided with the lower electrode 12a can be reduced, and the slide operation load can be reduced. can do. Accordingly, a smooth slide operation can be realized, and the operator can obtain a good slide operation feeling. Further, since the slide sheet 13a is provided on the back surface of the upper electrode 13b made of a conductive rubber-like elastic body, the upper electrode 13b can be hardly deformed by the rigidity of the slide sheet 13a, and the upper electrode 13b and the lower electrode 12a can be prevented from being deformed. The interval can be kept constant. Therefore, it is possible to accurately detect the slide operation position during the slide operation.

  Since the metal disc spring 13e and the press detection electrode 12b are provided, it is possible to detect the change in the capacitance between the metal disc spring 13e and the press detection electrode 12b and output whether or not the key top 13c is pressed. .

Second Embodiment [FIGS. 5 to 7] :
A capacitive pointing device 21 of the second embodiment is shown in FIGS. FIG. 5 is a cross-sectional view of the capacitive pointing device 21, and FIG. 6 is an explanatory diagram of the lower electrode in the capacitive pointing device 21. FIG. 7 is an explanatory diagram of a lower electrode different from FIG.
The capacitive pointing device 21 is not provided with a metal disc spring on the operation member, and is not provided with a pressing detection electrode on the circuit board 22 serving as a fixing member. That is, unlike the capacitive pointing device 11 of the first embodiment, it does not have a function of detecting whether or not a key top is pressed.

The capacitive pointing device 21 includes a slide sheet 13a, an upper electrode 13b, a key top 23c as an “operation unit”, a fixing sheet 13d for fixing the key top 23c, a bellows portion 13f, and a fixing portion 13g as the operation member 23. I have.
However, since there is no disc spring, the key top 23c has an integrated pusher portion 23k, and this pusher portion 23k supports the keytop 23c like a support.
Further, as shown in FIG. 6, the fixing member 22 includes a lower electrode 22a, and the electrode is formed in a substantially circular shape with a small annular inner diameter. In FIG. 6, the upper electrode 13b is indicated by a two-dot chain line.

Instead of the lower electrode 22a, the lower electrode 12a having the shape shown in FIG. 7 can be used.
The lower electrode 12a is formed in such a size that its inner diameter is slightly larger than the outer diameter of the key top 23c and does not overlap the area of the key top 23c on projection.
The lower electrode 12a can reduce the overlap of the finger with the lower electrode 12a on the projection, and can accurately detect the sliding direction and the sliding amount of the key top 23c by reducing the influence of the finger on the lower electrode 12a. it can.

An example of the method for manufacturing the capacitive pointing device 21 will be described.
First, the slide sheet 13a, the upper electrode 13b, the bellows portion 13f, and the fixing portion 13g are integrally formed, and a double-sided tape 13m is attached to the operation surface side of the upper electrode 13b and the fixing portion 13g. Next, the annular fixed sheet 13d is inserted into a mold for forming the key top 23c, and the fixed sheet 13d and the key top 23c are integrally formed. Thereafter, the fixing sheet 13d is attached to the double-sided tape 13m of the upper electrode 13b to obtain the operation member 23. Then, the double-sided tape 13 m of the fixing portion 13 g in the operation member 23 is attached to the top cover 14. Thereafter, the top cover 14 integrated with the operation member 23 and the circuit board 22 provided with the lower electrode 22a are assembled to obtain the capacitive pointing device 21.

  According to the capacitive pointing device 21, since the ring shape without the upper electrode 13b is formed at the center position of the key top 23c, the influence of the finger on the upper electrode 13b can be reduced, and the slide operation is performed. The sliding direction and sliding amount of the key top 23c can be accurately detected.

Third Embodiment (FIG. 8) :
An electrostatic capacitance type pointing device 31 of the third embodiment is shown in FIG. FIG. 8 is a cross-sectional view of the capacitive pointing device 31.
The capacitive pointing device 31 has a structure for electrically connecting the operation member 33 and the fixing member 12 that is the circuit board 12.

  The circuit board 12 as the fixing member 12 is provided with a ground electrode 12c in addition to the lower electrode 12a and the pressing detection electrode 12b. The ground electrode 12 c is located on the surface of the operation member 33 that faces the fixed portion 33 g.

The operation member 33 includes a slide portion 13a, an upper electrode 13b, a key top 13c, a fixed sheet 13d, a metal disc spring 13e, a bellows portion 13f, a fixing portion 33g outside the bellows portion 13f, and further includes a metal plate 33p. ing.
The metal plate 33p is a member that holds the shape of the fixed portion 33g. In the present embodiment, the metal plate 33p is disposed on the operation surface side of the fixed portion 33g, and is formed in an annular shape so as not to contact the upper electrode 13b and the bellows portion 13f. ing. The ring-shaped inner edge has a circular shape slightly larger than the inner shape of the fixed portion 33g, and the outer edge is formed in a shape slightly smaller than the outer shape of the fixed portion 33g. The metal plate 33p can be reduced in weight by providing a notch having an appropriate shape in the surface. Further, the metal plate 33p can be covered with a resin film from the operation surface side and fixed to the fixing portion 33g, and can be made difficult to be detached from the fixing portion 33g.
As the material of the metal plate 33p, a metal that is not easily corroded and can be easily thinned can be used. For example, stainless steel, brass, aluminum and the like can be exemplified.
Although the metal plate 33p is used in the present embodiment, a resin plate can be used instead of the metal plate 33p if the reinforcement of the operation member 33 is considered without considering grounding.

The fixing portion 33g is provided with a through hole 33n penetrating through the wall thickness, and a connector 35 for electrically connecting the metal plate 33p and the ground electrode 12c is provided in the through hole 33p.
The connector 35 is a member that electrically connects the metal plate 33p and the ground electrode 12c, and is formed in a column shape. The connector 35 is formed of a rubber-like elastic conductive portion 35a exposed on the upper and lower surfaces and a rubber-like elastic insulating portion 35b covering the side surface of the conductive portion 35a. Instead of the connector 35, a metal pin provided on the ground electrode 12c can be used.

An example of a method for manufacturing the capacitive pointing device 31 will be described.
First, the slide sheet 13a, the upper electrode 13b, the bellows portion 13f, and the fixing portion 33g are integrally formed, and the metal plate 33p that is cut out on the operation surface side of the fixing portion 33g is disposed, and then the upper electrode 13b and the fixing portion 33g are arranged. Adhere double-sided tape 13m to the operation side. Next, the fixed sheet 13d and the key top 13c are integrally formed. Thereafter, the fixing sheet 13d is adhered to the double-sided tape 13m of the upper electrode 13b, and the operation member 33 is obtained. Then, the double-sided tape 13 m of the fixing portion 33 g in the operation member 33 is attached to the top cover 14. Thereafter, while inserting the connector 35 into the through hole 33n of the fixing portion 33g, the top cover 14 integrated with the operation member 33 and the circuit board 12 are assembled to obtain the capacitive pointing device 31.

According to the capacitance type pointing device 31, since the metal plate 33p is provided, the bellows portion 13f can be restrained from the outside so that the key top 13c after the slide operation can be easily returned to the initial position, and repeated slide operations. Can be accurately detected.
Further, since the metal plate 33p is connected to the ground electrode 12c, it is difficult to accumulate static electricity on the operation member 33, and the capacitance generated between the upper electrode 13b and the lower electrode 12a is affected. It can be difficult to give.

Fourth Embodiment (FIG. 9) :
A capacitive pointing device 41 according to the fourth embodiment is shown in FIG. FIG. 9 is a cross-sectional view of the capacitive pointing device 41.
In the capacitive pointing device 41, a through-hole electrode 43r is provided on the slide sheet 43a.

The capacitive pointing device 41 includes an operation member 43 and a fixing member 12.
The operation member 43 includes a slide sheet 43a, an upper electrode 13b, a key top 13c, a fixed sheet 13d, a metal disc spring 13e, a bellows portion 13f, and a fixed portion 13g.
Unlike the slide sheet 13a in the first embodiment, the slide sheet 43a is provided with a through hole 43q that penetrates the wall thickness at the center position of the metal disc spring 13e. A through-hole electrode 43r is formed in the through hole 43q.

An example of a method for manufacturing the capacitive pointing device 41 will be described.
First, the slide sheet 43a provided with the through-hole electrode 43r, the upper electrode 13b, the bellows portion 13f, and the fixing portion 33g are integrally formed, and the double-sided tape 13m is attached to the operation surface side of the upper electrode 13b and the fixing portion 33g. Next, the fixed sheet 13d and the key top 13c are integrally formed. Thereafter, the fixing sheet 13d is adhered to the double-sided tape 13m of the upper electrode 13b, and the operation member 43 is obtained. Then, the double-sided tape 13 m of the fixing portion 33 g in the operation member 43 is attached to the top cover 14. Thereafter, the top cover 14 integrated with the operation member 43 and the circuit board 12 are assembled to obtain the capacitive pointing device 41.

  According to the capacitive pointing device 41, since the slide sheet 43a has the through-hole electrode 43r, the position of the press detection electrode 12b is set to the length “t” shown in FIG. 9 in the thickness direction of the slide sheet 43a. As a result, it is possible to approach the top of the metal disc spring 13e apparently, and the amount of change in capacitance between the metal disc spring 13e and the pressing detection electrode 12b can be increased as compared with a slide sheet without a through-hole electrode. Thereby, it is possible to easily detect the pressing operation of the key top 13c.

  A common modification will be described for the capacitive pointing devices 11, 21, 31, 41 of the above embodiments. The capacitive pointing device 11 will be described as a representative example.

Common modification of each embodiment [FIG. 10] :
In the capacitive pointing device 11 of the first embodiment, the example in which the upper electrode 13b, the bellows portion 13f, and the fixing portion 13g are integrally formed of a conductive rubber-like elastic body has been shown, but the upper electrode 13b is electrically conductive. The bellows portion 13f and the fixing portion 13g are formed of an insulating rubber-like elastic body, and the conductive rubber-like elastic body and the insulating rubber-like elastic body are integrally formed. can do. Such a capacitive pointing device 51 is shown in FIG.
Since the conductive rubber-like elastic body is formed by uniformly dispersing conductive particles in an insulating rubber, the addition of the conductive particles may not exhibit the durability and resilience inherent to the rubber material. However, if the bellows portion 13f is formed of an insulating rubber-like elastic body, the durability and rebound resilience of the bellows portion 13f can be made the original characteristics of the rubber material. It can be made easy to return to the shape. Therefore, the key top 13c after the slide operation can be easily returned to the initial position, and the repeated slide operation can be accurately detected.

  Each of the above embodiments is an example of the capacitance-type pointing device of the present invention, and the components shown in the above embodiments are appropriately changed to the components shown in the other embodiments as long as no contradiction arises. Can do.

11 Capacitive type pointing device (first embodiment)
12 Fixing member (circuit board)
12a Lower electrode 12b Press detection electrode 12c Ground electrode 13 Operation member 13a Slide sheet 13b Upper electrode 13c Key top (operation unit)
13d fixed sheet 13e metal disc spring 13f bellows part 13g fixed part 13h annular rib 13k pusher part 13m double-sided tape 14 top cover (exterior member)
14a Through-hole 21 Capacitance type pointing device (second embodiment)
22 Fixing member (circuit board)
22a Lower electrode 23 Operation member 23c Key top (operation part)
23k Pusher 31 Capacitive Pointing Device (Third Embodiment)
33 Operation member 33g Fixed part 33n Through-hole 33p Metal plate 35 Connector 35a Conductive part 35b Insulating part 41 Capacitive pointing device (4th Embodiment)
43 Operation member 43a Slide sheet 43q Through-hole 43r Through-hole electrode 51 Capacitive pointing device (common modification of each embodiment)

Claims (6)

In the capacitance type pointing device that detects the change in capacitance between the upper electrode and the lower electrode by sliding the operation member having the upper electrode relative to the fixing member having the lower electrode,
The operation member includes an operation unit composed of a key top, and an upper electrode around the operation unit.
An electrostatic capacitance type pointing device, wherein the fixing member includes a lower electrode formed by dividing a central portion into a circular shape and being divided into a plurality of portions.   2. The capacitive pointing device according to claim 1, wherein the upper electrode is made of a conductive rubber-like elastic body, and the operation member further includes a slide sheet that covers the lower side of the upper electrode and faces the lower electrode.   The operation member further includes a bellows-like bellows portion connected to the upper electrode, and a fixing portion that is fixed to an exterior member positioned outside the key top, and the bellows portion, the fixing portion, and the upper electrode are electrically conductive. 3. The capacitive pointing device according to claim 2, wherein the capacitive pointing device is integrally formed of the rubber-like elastic body.   The capacitance-type pointing device according to claim 3, wherein the operation member includes a metal plate that holds the shape of the fixed portion. The operation member further includes a disc spring between the key top and the slide sheet,
The capacitive pointing device according to any one of claims 2 to 4, wherein the fixing member further includes a pressing detection electrode in the center of the lower electrode.   6. The capacitive pointing device according to claim 5, wherein a through hole is provided in the slide sheet at a portion facing the center of the disc spring, and a through hole electrode is provided in the through hole.

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