JP2002236552A - Coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinate input device which enables vertical input with high precision and whose production in cost is reduced by decreasing the number of components. SOLUTION: At the center part of a fixed electrode 10 formed on a circuit board 9, a switch circuit 11 having a couple of mutually insulated contact parts 11a and 11b is formed, a dome-shaped metal contact 8 which can elastically deform is arranged above the switch circuit 11, and a depression part 3 which can press the metal contact 8 is formed integrally with a key top 1. When the key top 1 is operated in parallel to the circuit board 9 as shown by arrows X and Y, the elastic member 7 elastically deforms through a slider 4 and a gap G varies. When the operation surface 2b on the depression part 3 is pressed at right angles to the circuit board 9 as shown by an arrow Z, the metal contact 8 is pressed against the depression part 3 to elastically deform and the contact parts 11a and 11b electrically conduct to each other through the metal contact 8 to switch over the contact of the switch circuit 11. Consequently, the metal contact 8 can be pressed directly by pressing the key top 1 and the vertical input can be done with high precision.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device, and more particularly to a coordinate input device which can be input by using a change in capacitance, for example, used for a personal computer or a remote controller.

[0002]

2. Description of the Related Art Conventionally, various coordinate input devices using changes in capacitance have been proposed. Such a capacitance-type coordinate input device can properly detect a change in capacitance and perform a normal coordinate input even if the surrounding environmental temperature changes. Is increasing. In such a conventionally proposed capacitive coordinate input device, an elastic member is connected to a keytop via a slider, and a movable electrode is formed on the elastic member,
A first fixed electrode composed of a plurality of electrodes divided in a circumferential direction is formed on a circuit board on a side facing the movable electrode, and between the movable electrode and each electrode of the first fixed electrode, For example, a gap of 100 μm to 150 μm is formed.

In the initial state, a capacitance of about 1 to 2 pF (picofarad) is provided between the movable electrode having such a predetermined gap and the plurality of divided first fixed electrodes. Had been formed. Then, when the operator moves the key top to one side in the horizontal direction with a finger or the like, this movement is transmitted to the elastic member via the slider, and the movable electrode of the elastic member is elastically deformed. Due to the deformation of the movable electrode, the gap between the movable electrode on one side and the first fixed electrode is narrowed, and the capacitance changes to the plus side by about several pF with respect to the initial value.

[0004] By detecting the input in the horizontal direction based on the change in the capacitance, a cursor on a display such as a personal computer can be horizontally moved to a desired position. When the center of the keytop is pressed toward the circuit board while the cursor on the display is horizontally moved to a desired position, the actuator below the keytop presses the movable electrode at the lower center of the elastic member. Then, the gap between the first fixed electrode and the insulated second fixed electrode formed on the circuit board at the position facing the movable electrode at the lower center of the elastic member changes, and the capacitance of this portion is reduced. Change to the plus side. When the change in capacitance between the movable electrode and the second fixed electrode is equal to or greater than a predetermined value, it is possible to detect that the input has been made in the vertical direction and determine, for example, a cursor that has been moved to a desired position. ing.

[0005]

However, in the coordinate input device proposed in the prior art as described above, when the key top is depressed and input is performed in the vertical direction, the movable electrode is displaced due to a variation in the pressing force of the key top. In some cases, a change in capacitance between the first fixed electrode and the second fixed electrode does not exceed a predetermined value, and input in the vertical direction may become unstable. Further, in the conventionally proposed coordinate input device, the key top and the actuator are separate bodies, and the number of parts is large, and the assemblability is poor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and provides a coordinate input device which can perform input in the vertical direction reliably, reduces the number of parts, and has good assemblability. With the goal.

[0007]

According to a first aspect of the present invention, there is provided a coordinate input device for detecting a circuit board and an input in a direction parallel to the circuit board on a surface of the circuit board. A fixed electrode provided by dividing a plurality of possible electrodes in the circumferential direction, and an elastic member having a movable electrode formed at a portion facing at least a gap of a predetermined dimension between the fixed electrode and the fixed electrode are provided. A slider connected to the elastic member; and a key top which is engaged with the slider and is operable in a direction parallel to the circuit board. A dome-shaped elastically deformable metal contact is disposed above the switch circuit, and a pressing portion capable of pressing the metal contact is integrally formed with the key top, and the key top is formed. When the lever is operated in a direction parallel to the circuit board, the elastic member is elastically deformed via the slider to change the gap, and the key top on the pressing portion is moved in a direction orthogonal to the circuit board. When pressed, the metal contact is pressed by the pressing portion to be elastically deformed, and the pair of contact portions are conducted through the metal contact to switch the contact of the switch circuit.

As a second means for solving the above-mentioned problems, the pressing portion of the key top has a shaft portion capable of pressing the metal contact, and this shaft portion is attached to the elastic member. In the fitted state, the key top is slidable in a direction orthogonal to the circuit board, and the key top is elastically urged in a direction away from the circuit board by contacting the tip of the shaft with the metal contact. The configuration was adopted.

As a third means for solving the above problem, the key top has an operation surface parallel to the circuit board, and is provided on an outer peripheral portion of the operation surface at right angles to the operation surface. A configuration was formed in which a protrusion protruded in the direction was formed.

As a fourth solution for solving the above-mentioned problem, the elastic member has a fitting hole in which the shaft portion of the pressing portion is fitted, and the elastic member is provided at the distal end portion of the shaft portion. A flange having a larger outer dimension than the shaft is formed, and the key top in which the shaft is fitted in the fitting hole is prevented from being removed from the elastic member by the flange.

As a fifth means for solving the above-mentioned problems, a housing for holding the slider so as to be movable in a direction parallel to the circuit board is provided, and an inner surface of a side wall of the housing is provided with the elastic member. The outer peripheral portion was attached in close contact.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coordinate input device according to the present invention will be described below with reference to FIGS. First, FIG. 1 is a plan view of a coordinate input device of the present invention, FIG. 2 is a cross-sectional view of a main part of FIG. 1, and FIG. 3 is a plan view of a circuit board according to the present invention.

In the coordinate input device of the present invention, as shown in FIGS. 1 and 2, a key top 1 is provided at the top. The key top 1 is made of a hard resin material or the like, and has a disk-shaped key top portion 2 at an upper portion and a pressing portion 3 protruding downward from a lower center of the key top portion 2 and has an outer shape formed in a frame shape. Have been. The key top portion 2 has a projection 2a formed on an outer peripheral portion at an upper portion in the drawing, and an operation surface 2b formed in a concave shape by being lowered by one step on an inner peripheral side of the projection 2a. That is, the key top 1 has an operation surface 2b parallel to a circuit board 9 described later, and a protrusion 2a protruding in a direction orthogonal to the operation surface 2b is formed on an outer peripheral portion of the operation surface 2b. .

An engaging recess 2c is formed on the lower surface of the key top portion 2, and a pressing portion 3 protruding downward from the central portion is formed in the engaging recess 2c. The pressing portion 3 includes a base 3a formed in the engagement recess 2c and a shaft 3b having a smaller diameter than the base 3a protruding from the base 3a.
A flange portion 3d having a diameter larger than the shaft portion 3b and smaller than the base portion 3a is formed on the engaging concave portion 2c of the key top portion 2. Have been. A fitting hole 4b into which the base 3a of the pressing portion 3 of the key top 1 fits is formed through the center of the engagement protrusion 4a.

The lower part of the fitting hole 4b has a fitting hole 4b.
A connection recess 4c having a larger diameter dimension is formed.
In addition, a circular flange-shaped flange portion 4d is formed on the outer peripheral portion of the lower portion of the slider 4. Such a slider 4
The flange 4d is loosely fitted between the upper wall 5a of the housing 5 made of a metal plate or the like and the bracket 6 formed by cutting and bending a part of the housing 5, and is horizontally moved by arrows X and Y. It is movable.

The housing 5 has a rectangular outer shape.
Side walls 5b are formed on the four outer peripheral portions by drawing or the like,
The lower part is open. The housing 5 is formed with a restricting portion 5c, which is indicated by a two-dot chain line, that restricts the amount of horizontal movement of the slider 4 in the X and Y directions by cutting and bending a part of the upper wall 5a. Also, the connecting recess 4c of the slider 4 has
The connection protrusion 7a of the elastic member 7 is press-fitted, and the sladder 4 and the elastic member 7 are connected. This elastic member 7
Is made of, for example, elastic rubber having conductivity,
A cylindrical connecting protrusion 7a is provided at the center thereof so as to protrude upward in the drawing.

A first fitting hole 7b into which the pressing portion 3 of the key top 1 is slidably fitted in a vertical direction in the drawing is formed through the center of the connecting projection 7a. 7
A second fitting hole 7c having a larger diameter than the first fitting hole 4b is formed below b. The elastic member 7 is formed with an arm 7d extending in the outer peripheral direction, and a movable electrode 7e is formed by recessing a lower portion of the arm 7d in a circular shape by a predetermined dimension.

The arm 7d has an outer peripheral portion 7f outside the movable electrode 7e, and the outer peripheral portion 7f is connected to the movable electrode 7e.
Is formed so as to be thicker than the arm portion 7d of the portion where the is formed, and the upper surface is held by the bracket 6 and the lower surface is held by the ground electrode 12 of the circuit board 9 described later. The outer peripheral portion 7f of the elastic member 7 has a rectangular outer peripheral end surface, and the rectangular outer peripheral end surface is closely fitted to the inner surface of the side wall 5b of the housing 5. Therefore, even if the coordinate input device of the present invention accidentally drops water drops or the like from above,
The water droplets can be prevented from entering a circuit board 9 to be described later from a contact portion between the outer peripheral end surface of the elastic member 7 and the inner surface of the side wall 5b of the housing 5.

When the key top 1 is operated in the horizontal directions indicated by arrows X and Y, the connecting member 7a is pressed in the horizontal direction via the slider 4, and the elastic member 7 is moved by the movable electrode formed on the arm 7d. 7e is elastically deformed. In the elastic member 7, a switch housing 7g having a diameter larger than the second fitting hole 7c is formed at a predetermined depth in the center of the lower surface, and the switch housing 7g and the movable electrode are formed around the switch housing 7g. A projection 7h is formed to partition the projection 7e from the projection 7e. The lower surface of the projection 7h and the outer peripheral portion 7f of the elastic member 7 abut on a circuit board 9 described later, and the movable electrode 7
e, a gap G having a predetermined size is formed.

The pressing portion 3 of the key top 1 has a base portion 3a located in a fitting hole 4b of the slider 4 and a shaft portion 3b fitted in a first fitting hole 7b of the elastic member 7 with a predetermined gap. And
The flange 3d is fitted in the second fitting hole 7c, so that the tip 3c is located in the switch housing 7g. Such a key top 1 is prevented from dropping upward by a flange 3d fitted in the second fitting hole 7c of the elastic member 7. The slider 4 fitted into the engagement recess 2c of the key top portion 2 has a predetermined gap formed between the upper surface of the engagement projection 4a and the bottom surface of the engagement recess 2c. It can be lowered downward.

The elastic member 7 of the pressing portion 3 of the key top 1
When the flange 3d is pressed into the first fitting hole 7b of the elastic member 7 by applying a load to the operation surface 2b above the pressing portion 3, the first fitting hole 7b is elastically deformed to the outside. Spread,
The flange 3d is pushed into the second fitting hole 7c. A metal contact 8 made of an elastically deformable dome-shaped stainless steel plate or the like is provided below the pressing portion 3 incorporated in the elastic member 7. 3, the key top 1 is elastically urged upward in a direction away from a circuit board 9 described later. Then, the operation surface 2b of the key top unit 2
Is pressed by an operator's finger or the like, the pressing portion 3 slides in the direction of the arrow Z, and the metal contact 8 is elastically deformed to be flat. When the metal contact 8 is flat, a click feeling is transmitted to the operator's finger pressing the key top 1.

A circuit board 9 is provided below the elastic member 7, and the circuit board 9 is made of a hard material such as a glass epoxy resin.
The fixed electrode 1 as shown in FIG.
0 is formed. The fixed electrode 10 includes first to fourth conductive electrodes 10a to 10d equally divided in a circumferential direction.
Are formed by printing or the like, and are electrically insulated from each other. The first to fourth electrodes 10a to 10d are
The upper part is covered with a dielectric film (not shown), and is insulated from the upper movable electrode 7e and the protrusion 7h.

In the center of the fixed electrode 10, a switch circuit 11 insulated from the electrodes 10a to 10d is provided.
Are formed by printing or the like. The switch circuit 11
No dielectric film is formed on the upper part of the switch, and the switch circuit 11 is exposed. In the switch circuit 11, one contact portion 11a is formed in an annular shape, and the other contact portion 11b is formed in a circular shape on the inner peripheral side of the one contact portion 11a. That is, a switch circuit 11 having a pair of contact portions 11a and 11b insulated from each other is formed at the center of the fixed electrode 10.

A metal contact 8 is provided on the switch circuit 11, and an outer peripheral portion of the metal contact 8 and one contact portion 11a are in contact with each other and are electrically connected. Further, a ground electrode portion 12 insulated from the fixed electrode 10 is formed so as to surround the fixed electrode 10 on the circuit board 9. The outer peripheral portion of the ground electrode portion 12 is formed in a rectangular shape, and the lower surface of the outer peripheral portion 7f of the elastic member 7 is located on the ground electrode portion 12, so that the elastic member 7 and the ground electrode 12 are electrically connected. I have. The metal contact 8 located on the switch circuit 11 is pressed by the pressing portion 3 by pressing the operation surface 2b of the key top 1 below the arrow Z, and is elastically deformed to be flat. Then, the pair of contact portions 11
The terminals a and 11b conduct through the metal contact 8, the contact of the switch circuit 11 is switched, and the input in the vertical direction can be performed.

Each of the electrodes 10a to 10d and the pair of contact portions 11a and 11b are connected to an FPC (flexible printed circuit board) 13 provided on the lower surface of the circuit board 9 by a through hole 9a formed in the circuit board 9. Are electrically connected to the respective circuit patterns. Also, F
The circuit pattern of the PC 13 is provided with control means, for example, an IC chip (not shown) capable of detecting a change in capacitance.

The operation of the coordinate input device of the present invention having such a configuration will be described. In the standby state (initial state) before the key top 1 is operated in the horizontal directions of the arrows X and Y, the movable electrode 7e and The capacitance value between each of the electrodes 10a to 10d is read by the control means of the FPC 13. In FIG. 2, the key top 1 is connected to the circuit board 9.
When the operation is performed in a direction parallel to, for example, the left direction, the elastic member 7
In this case, the connecting projection 7a tilts to the left in the figure, and the arm 7d on the left in the figure deforms downward. Then, a part of the movable electrode 7e on the left side in the figure comes into close contact with the second electrode 10b of the fixed electrode 10 via the dielectric film, and the capacitance between the movable electrode 7e and the second electrode 10b changes to the plus side. At this time, the gap G between the fourth electrode 10d on the opposite side of the second electrode 10b and the movable electrode 7e is wider than the initial state, and the capacitance changes to the minus side. The control means detects a change in the capacitance of the second electrode 10b, and moves a cursor on a display of, for example, a personal computer (not shown) to a desired position in the left direction in accordance with the change in the capacitance. It has become.

In FIG. 2, when the key top 1 is operated in a direction parallel to the circuit board 9, for example, rightward, the connecting projection 7a of the elastic member 7 is tilted rightward in the figure, and the right arm shown in the figure. 7d is deformed downward, and a part of the movable electrode 7e on the right side in the figure is in close contact with the fourth electrode 10d of the fixed electrode 10 via the dielectric film, so that the capacitance between the fourth electrode 10d and the fourth electrode 10d is positive. Changes to When the control means detects the change in capacitance of the fourth electrode 10d, the cursor on the display of the personal computer is moved to a desired position in the right direction, for example, in accordance with the change in capacitance. .

When the cursor is moved to a desired position on the display and the operation surface 2b of the key top 1 is lightly pressed with a finger or the like in a direction orthogonal to the circuit board 9 indicated by the arrow Z, the pressing portion 3 The tip 3c presses the metal contact 8.
Then, the dome-shaped metal contact 8 is elastically deformed into a flat shape, and one and the other contact portions 11a, 1a of the switch circuit 11 are connected.
1b conducts, and the contact of the switch circuit 11 is switched. When the control means detects the switching of the contact,
The cursor moved to a desired position on the display can be determined. When the horizontal or vertical load applied to the key top 1 is released, the key top 1 and the elastic member 7 are respectively returned to the original initial state by the elastic force of the elastic member 7 or the metal contact 8. It automatically returns to the state.

Although the elastic member 7 has been described as being made entirely of conductive rubber or the like having conductivity, the elastic member 7 is formed of insulating rubber, and has a movable electrode 7e and a movable electrode 7e.
Only the lower surface of the outer peripheral portion 7f connected to e may be formed of a conductive material. That is, the elastic member 7 may be any member provided with a conductive movable electrode at a portion opposed to the fixed member 10 with at least a gap of a predetermined dimension.

[0030]

As described above, in the coordinate input device according to the present invention, the pressing portion capable of pressing the metal contact is formed integrally with the key top, and the key top on the pressing portion is perpendicular to the circuit board. When pressed, the metal contact is pressed by the pressing portion and is elastically deformed, so that the pair of contact portions are conducted through the metal contact and the contact of the switch circuit is switched, so that
It is possible to recognize that the contact has been switched by a click feeling generated when the dome-shaped metal contact is pressed by the pressing portion integrally formed on the key top in the vertical input.
For this reason, it is possible to provide a coordinate input device that can perform the input in the vertical direction reliably and has a good operation feeling by a click feeling. Further, since the pressing portion is formed integrally with the key top, the number of parts can be reduced, and the assembling property can be improved.

The pressing portion of the key top is slidable in a direction orthogonal to the circuit board in a state of being fitted to the slider and the elastic member. Since it is elastically urged away from the key contact, the pressing operation of the metal contact by the key top becomes easy, and the input in the vertical direction can be reliably performed.

The key top is provided on the outer peripheral portion of the operation surface.
Since the projection is formed to project in the direction perpendicular to the operation surface, when the key top is operated in the horizontal direction with the operator's finger etc.,
The projection allows a finger or the like to be reliably positioned on the operation surface and guided. Therefore, the horizontal operation of the key top can be easily and reliably performed.

Further, a flange having a larger outer dimension than the shaft is formed at the tip of the pressing portion of the keytop, and the keytop having the shaft fitted into the fitting hole is prevented from coming off from the elastic member by the flange. Therefore, the key top does not fall out of the elastic member during transportation or the like.

Further, since the outer peripheral end of the elastic member is closely attached to the inner surface of the side wall of the housing, even if an operator accidentally spills a liquid such as water from above, the water droplets are generated by the fixed electrode on the circuit board. Alternatively, it is possible to provide a coordinate input device having a waterproof function capable of preventing the switch from entering the switch circuit.

[Brief description of the drawings]

FIG. 1 is a plan view of a coordinate input device according to the present invention.

FIG. 2 is a sectional view of a main part of FIG.

FIG. 3 is a plan view of a circuit board according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Key top 2 Key top part 2a Projection part 2b Operation surface 2c Engagement concave part 3 Press part 3a Base part 3b Shaft part 3c Tip part 3d Flange part 4 Slider 4a Engagement protrusion 4b Fitting hole 4c Connection concave part 4d Flange part 5 Housing 5a upper wall portion 5b side wall 5c regulating portion 6 bracket 7 elastic member 7a connecting protrusion 7b first engaging hole 7c second engaging hole 7d arm 7e movable electrode 7f outer peripheral portion 7g switch housing portion 8 metal contact 9 circuit board 10 Fixed electrode 11 Switch circuit 11a One contact part 11b The other contact part 12 Ground electrode 13 FPC

Claims (5)

[Claims] A fixed electrode provided on a surface of the circuit board, and a plurality of electrodes capable of sensing an input in a direction parallel to the circuit board divided in a circumferential direction, and at least the fixed electrode; An elastic member having a movable electrode formed at an opposing portion with a gap of a predetermined size is provided, and a slider connected to the elastic member is engaged with the slider in a direction parallel to the circuit board. A switch circuit having a pair of contact portions insulated from each other at the center of the fixed electrode, and a dome-shaped elastically deformable metal contact is disposed above the switch circuit. When the key top is formed integrally with the key top and the key top is operated in a direction parallel to the circuit board, the elastic member is elastically deformed via the slider. When the gap changes, and the key top on the pressing portion is pressed in a direction orthogonal to the circuit board, the metal contact is pressed by the pressing portion and elastically deforms, and the pair of contacts A coordinate input device, wherein a portion is conducted through the metal contact to switch the contact of the switch circuit. 2. The pressing part of the key top has a shaft part capable of pressing the metal contact, and a direction perpendicular to the circuit board when the shaft part is fitted to the elastic member. 2. The coordinate input device according to claim 1, wherein the key top is elastically urged in a direction in which the tip of the shaft portion comes into contact with the metal contact and the key top moves away from the circuit board. 3. The key top has an operation surface parallel to the circuit board, and a protrusion protruding in a direction perpendicular to the operation surface is formed on an outer peripheral portion of the operation surface. 3. The coordinate input device according to claim 1, wherein 4. The elastic member has a fitting hole in which the shaft portion of the pressing portion fits, and forms a flange having a larger outer dimension than the shaft at the tip of the shaft. 4. The coordinate input device according to claim 1, wherein the key top having the shaft portion fitted in the fitting hole is prevented from being removed from the elastic member by the flange portion. 5. 5. A housing for holding the slider movably in a direction parallel to the circuit board, wherein an outer peripheral end of the elastic member is attached to an inner surface of a side wall of the housing in close contact. The coordinate input device according to claim 1.