JP5855441B2 - Force sensor unit - Google Patents

Description

  The present invention relates to a force sensor unit for an apparatus using a force sensor.

  JP-T-2008-515089 discloses a conventional touch panel input device in which force sensors are arranged at the four corners or around the panel as an example of a device using force sensors. In this device, the pressure applied to the touch panel is received by four force sensors, and the position of the panel touched by the operator is specified by calculating the balance of signals proportional to the pressure output from each force sensor. To do.

Japanese translation of PCT publication No. 2008-515089

  In the conventional structure, in order to increase the accuracy of specifying the touch position, the pressing force applied to the panel is increased to increase the output of the force sensor. However, if the panel is pressed with a strong force to obtain a large output from the force sensor, the force sensor may be damaged.

  An object of the present invention is to provide a force sensor unit that eliminates the possibility of damage to the force sensor.

  An apparatus in which the force sensor unit of the present invention is used includes a pressure receiving member having a surface to which a pressing force is applied, a base member facing the back surface of the pressure receiving member, and a predetermined interval between the pressure receiving member and the base member. And three or more force sensors that output information necessary for specifying the position to which the pressing force is applied. In the present invention, three or more force sensors are disposed between the pressure receiving member and the base member via the holding mechanism. The holding mechanism applies a predetermined bias force to the force sensor in a state where the pressing force is not applied to the surface of the pressure receiving member, and when the pressing force is applied to the surface, the holding mechanism is biased in proportion to the magnitude of the pressing force. Configured to reduce force. When such a holding mechanism is used, the bias force decreases as the pressing force applied to the pressure receiving member increases. As a result, the force applied to the force sensor decreases as the pressing force increases. As a result, even if the operator strongly presses the pressure receiving member with a general sense, the force sensor is not damaged. Since the amount of change in the output of the force sensor when the pressing force is increased increases in proportion to the pressing force, the position specifying accuracy increases.

  The specific configuration of the holding mechanism is arbitrary. For example, the holding mechanism includes a sensor attachment portion that is positioned in a space between the pressure receiving member and the base member and to which the force sensor is attached, and is a first attachment member that is fixed to one member of the pressure receiving member and the base member. And a second attachment member that is fixed to the other member of the pressure receiving member and the base member, and a pressing force is applied to the surface of the pressure receiving member. A bias force applying means for applying a bias force to the force sensor via the bias force applying unit in a state where the force is not applied can be provided. When the first and second attachment members are used in this way, the structure of the holding mechanism is simplified.

  Moreover, it is preferable that the 1st attachment member has a fixing | fixed part formed integrally with a sensor attachment part and fixed to a base member. In this case, the force sensor is located between the sensor attachment portion of the first attachment member and the bias force applying portion of the second attachment member. The bias force applying means is disposed between the bias force applying portion of the second attachment member and the base member. The bias force applying means is deformed so as to be restored by the pressing force applied to the pressure receiving member, and when the pressing force is removed, the biasing force applying means restores the original shape and applies a return force to the pressure receiving member to return the pressure receiving member to the original position. It is configured. With such a configuration, the sensor mounting portion and the bias force applying portion function as a stopper for the pressure receiving member with respect to the base member. Therefore, even if an extremely large pressing force is applied to the pressure receiving member, the pressure receiving member is not damaged. When the pressing force applied to the pressure receiving member is released, the pressure receiving member returns to the original position.

  In order to increase the restoring force, the sensor attachment portion and the fixing portion of the second attachment member fixed to the pressure receiving member are deformably deformed by the pressing force, and when the pressing force is removed, the original force is removed. It is preferable to provide an additional bias force applying means for restoring the shape and returning the pressure receiving member to the original position.

  Preferably, the first and second attachment members, the bias force applying means, and the additional bias force applying means are combined to form one force sensor unit. Use of such a force sensor unit facilitates assembly of the touch panel input device.

  The structure of the holding mechanism is not limited to the above. For example, the fixing portion of the first attachment member has a structure including a parallel portion extending parallel to the sensor attachment portion, and a connecting portion that connects one end of the sensor attachment portion and one end of the parallel portion, and the second attachment member The fixing portion is configured to include a parallel portion extending in parallel with the bias force applying portion and a connecting portion that connects one end of the bias force applying portion and one end of the parallel portion. Then, the first attachment member and the second attachment member are arranged so that the sensor attachment portion and the bias force applying portion face each other, and the connection portion of the first attachment member and the connection portion of the second attachment member are arranged in parallel. combine. A bias force applying means is arranged between the sensor attachment portion of the first attachment member and the parallel portion of the second attachment member. Also in this case, the bias force applying means is deformed so as to be restored by the pressing force applied to the pressure receiving member, and when the pressing force is removed, the biasing force applying means restores the original shape and returns the pressure receiving member to the original position. Configure to give to. Even if the holding structure is configured in this way, the operation is the same as the holding structure described above. The sensor mounting portion and the bias force applying portion function as a stopper for the pressure receiving member with respect to the base member.

  The bias force applying means and the additional bias force applying means are preferably composed of a spring or an elastic member.

  A preferable sensor unit for a touch panel input device according to the present invention includes a sensor mounting portion in which the holding mechanism is positioned in a space between the pressure receiving member and the base member and the force sensor is mounted, and one of the pressure receiving member and the base member is provided. A second attachment fixed to the other member of the pressure receiving member and the base member, comprising a first attachment member fixed to the member and a bias force applying portion facing the sensor mounting portion with a force sensor interposed therebetween A biasing force applying unit configured to apply a biasing force to the force sensor via the biasing force applying unit in a state where the pressing force is not applied to the surface of the pressure receiving member; The first attachment member has a fixing portion that is formed integrally with the sensor mounting portion and fixed to the base member, and the second attachment member is formed integrally with the bias force applying portion and is a pressure receiving member. It has a fixed part fixed to. And a force sensor is located between the sensor attachment part of a 1st attachment member, and the bias force provision part of a 2nd attachment member. A bias force applying means is disposed between the bias force applying portion of the second attachment member and the base member. Then, between the sensor mounting portion and the fixing portion of the second attachment member fixed to the pressure receiving member, the pressure receiving member is deformably deformed by the pressing force, and when the pressing force is removed, the pressure receiving member is restored to its original shape. Additional bias force applying means for applying a return force to the original position to the pressure receiving member is provided.

(A) thru | or (C) are the top views, the front views, and the right view of the example which applied 1st Embodiment of the force sensor unit of this invention to the touchscreen input device. FIG. 2 is an exploded perspective view of the touch panel input device of FIG. 1. It is the III-III line expanded sectional view of FIG.1 (B). It is a figure used in order to demonstrate arrangement | positioning of the force sensor unit of 1st Embodiment shown in FIG. It is a figure which shows the structure of the principal part of 2nd Embodiment. It is a figure which shows the structure of the principal part of 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1A to 1C are a plan view, a front view, and a right side view of a touch panel input device 1 to which the first embodiment of the force sensor unit of the present invention is applied, and FIG. 3 is an exploded perspective view of the touch panel input device 1. FIG. FIG. 3 is an enlarged sectional view taken along line III-III in FIG. The touch panel input device 1 includes a panel member 3 as a pressure receiving member having a surface to which an operator applies a pressing force, a base member 5 facing the back surface of the panel member 3, and a predetermined interval between them. Four force sensor units 7 according to the embodiment of the present invention are provided, which are arranged between the member 3 and the base member 5 and output information necessary for specifying the position where the pressing force is applied. As shown in FIG. 2, the panel member 3 includes an acrylic transparent touch panel 31 and an acrylic frame 32. The touch panel 31 is joined to the upper surface of the frame body 32 by ultrasonic welding or the like. In the pair of side walls 33 positioned at both ends in the longitudinal direction of the frame body 32, two attachment holes 34 are formed at both ends in the width direction (direction perpendicular to the longitudinal direction and the thickness direction).

  The base member 5 includes a pair of flange portions 52 that are thinner than the base main body portion 51 at both ends in the longitudinal direction of the base main body portion 51. Two attachment holes 53 are formed at both ends of the pair of flange portions 52 in the width direction (the direction perpendicular to the longitudinal direction and the thickness direction of the base main body portion 51). Further, on the side surface of the base main body 51, fitting convex portions 54 are formed at both ends in the width direction. The four force sensor units 7 are attached to the four corners of the panel member 3 and the base member 5 using the attachment holes 34 of the frame 32 and the attachment holes 53 provided in the flange portion 52 of the base member 5.

  As shown in FIG. 3, the force sensor unit 7 of the present embodiment includes a force sensor 71 and a holding mechanism 72. The holding mechanism 72 includes a first attachment member 73, a second attachment member 74, a bias force applying unit 77, and an additional bias force applying unit 78. The first attachment member 73 is positioned in a space between the side wall 33 of the panel member 3 and the flange portion 52 of the base member 5, and is attached to the sensor attachment portion 73a to which the force sensor 71 is attached, and the sensor attachment portion 73a. And a fixing portion 73 b that is fixed to the flange portion 52 of the base member 5. The fixing portion 73b includes a parallel portion 73c extending in parallel with the sensor attachment portion 73a, and a connecting portion 73d that connects one end of the sensor attachment portion 73a and one end of the parallel portion 73c. In the present embodiment, the parallel portion 73 c is in contact with the flange portion 52 of the base member 5, and the connecting portion 73 d is in contact with the side surface of the base main body portion 51. The parallel portion 73c is formed with a through hole 73e (see FIG. 2) that matches the two attachment holes 53 provided in the flange portion 52. A screw 75 is screwed into the aligned mounting hole 53 and through hole 73e. The connecting portion 73d is formed with a pair of through holes 73f into which a pair of fitting convex portions 54 provided on the side wall of the base main body portion 51 are fitted.

  The second attachment member 74 is fixed to the inner wall surface of the side wall 33 of the frame body 32 of the panel member 3. The second attachment member 74 is integrally provided with a bias force applying portion 74a and a fixing portion 74b that face the sensor mounting portion 73a with the force sensor 71 interposed therebetween. The fixing portion 74b includes a parallel portion 74c extending in parallel with the bias force applying portion 74a, and a connecting portion 74d that connects one end of the bias force applying portion 74a and one end of the parallel portion 74c. In the first and second attachment members 73 and 74, the sensor attachment portion 73a and the bias force applying portion 74a face each other, and the connection portion 73d of the first attachment member 73 and the connection portion 74d of the second attachment member 74 Are combined in parallel. A bias force applying means is disposed between the sensor attachment portion 73 a of the first attachment member 73 and the parallel portion 74 c of the second attachment member 74. In the present embodiment, the parallel part 74 c and a part of the connecting part 74 d are in contact with the inner wall part of the side wall 33 of the frame body 32. The parallel portion 74c is formed with a through-hole 74f (FIG. 2) that fits with a pair of fitting convex portions (not shown) provided on the inner wall portion of the side wall 33 of the frame body 32. The connecting portion 74d is formed with a pair of through holes 74e aligned with the pair of mounting holes 34 provided in the side wall 33. Screws 76 are screwed into the aligned mounting holes 34 and through holes 74e, respectively.

  The force sensor 71 is fixed to the sensor attachment portion 73 a of the first attachment member 73 and is positioned between the sensor attachment portion 73 a and the bias force applying portion 74 a of the second attachment member 74. In this embodiment, a semiconductor force sensor disclosed in Japanese Patent No. 3830906 is used as the force sensor 71. This semiconductor force sensor has a structure in which a sphere is arranged on a diaphragm-like semiconductor substrate, and outputs a signal proportional to the force applied to the sphere. Bias force applying means 77 comprising two coil springs is provided between the bias force applying portion 74a of the second attachment member 74 and the parallel portion 73c of the first attachment member 73 located on the flange portion 52 of the base member 5. Is arranged. The tip ends of two screws 75 are inserted into the ends of the two coil springs. The bias force applying means 77 is deformed so as to be restored by the pressing force applied to the panel member 3, and when the pressing force is removed, the biasing force applying means 77 restores the original shape and restores the panel member 3 to the original position. To give. Moreover, in this Embodiment, between the sensor attaching part 73a and the parallel part 74c of the fixing | fixed part 74b of the 2nd attachment member 74 fixed to the panel member 3, it deform | transforms by a pressing force so that a restoring force is possible. When removed, an additional bias force applying means 78 including two coil springs is provided which restores the panel member 3 to its original position when it is removed and gives the panel member 3 a restoring force. Inside the one ends of the two coil springs constituting the additional bias force applying means 78, the tips of the fitting convex portions that are fitted into and protrude through the through holes provided in the parallel portion 74c of the second attachment member 74 are provided. It is mated.

  With this configuration, the sensor attachment portion 73 a and the bias force applying portion 74 a function as a stopper for the panel member 3 with respect to the base member 5. Therefore, even if an extremely large pressing force is applied to the panel member 3, the panel member 3 is not damaged. When the pressing force applied to the panel member is released, the panel member 3 quickly returns to the original position by the restoring force of the bias force applying unit 77 and the additional bias force applying unit 78. In the present embodiment, the first and second attachment members 73 and 74, the bias force applying means 77, and the additional bias force applying means 78 are combined to constitute one force sensor unit. When such a force sensor unit is used, the touch panel input device 1 can be easily assembled.

  In the touch panel input device 1 according to the present embodiment, the bias force applying unit 77 and the additional bias force applying unit 78 cooperate with each other in a state where no pressing force is applied to the surface of the panel member. The urging is performed in a direction away from the member 5 (pressing the bias force applying portion 74a against the force sensor 71 side). The necessary bias can be obtained by the bias force applying means 77 alone. However, if the additional bias force applying means 78 is used, the bias force can be more reliably applied to the bias force applying section 74a. When a pressing force is applied to the surface of the panel member 3, the bias force applying unit 77 and the additional bias force applying unit 78 are deformed (accumulated), and the bias force is reduced in proportion to the magnitude of the pressing force. As a result, the bias force decreases as the pressing force applied to the panel member 3 increases. The force applied to the force sensor 71 decreases as the pressing force increases. As a result, even if the operator strongly presses the panel member 3 with a general sense, the force sensor is not damaged. The amount of change in the output of the force sensor 71 when the pressing force is increased increases in proportion to the pressing force.

  In the apparatus of FIG. 1, as shown in FIG. 4, the two force sensor units 7 facing the longitudinal direction of the panel member 3 are symmetrical with respect to a center line C extending in a direction perpendicular to the longitudinal direction of the panel member 3. It is arranged to be. In this way, a common force sensor unit 7 can be used.

  In the above-described embodiment, the bias force applying unit 77 and the additional bias force applying unit 78 are used. However, the additional bias force applying unit 78 is provided in the holding mechanism 172 as in the second embodiment shown in FIG. Of course, only the bias force applying means 77 may be used without using it. In this case, since the second attachment member 174 does not need to be provided with an additional biasing force applying means, the length of the connecting portion 174d is the same as that of the second attachment member 74 shown in FIGS. It can be made shorter than the length of the part 74d. Therefore, according to the present embodiment, the height dimension of the force sensor unit 107 can be reduced.

  Further, as in the third embodiment shown in FIG. 6, only the additional bias force applying means 278 is used in the holding mechanism 272 without using the bias force applying means 77 shown in FIGS. Of course, it is good. In this case, since the second attachment member 274 does not need to be disposed inside the member corresponding to the bias force applying means 77, the length of the connecting portion 273d is the first attachment shown in FIGS. The length of the connecting portion 73d of the member 73 can be made shorter. Therefore, according to the present embodiment, the height dimension of the force sensor unit 207 can be reduced. In the third embodiment, the additional bias force applying means 278 constitutes the bias force applying means recited in the claims.

  In the above embodiment, the bias force applying means and the additional bias force applying means are constituted by coil springs. However, instead of the coil springs, elastic members, sponge-like members, air cushion members filled with air or the like are used. Of course you can.

  In the apparatus of FIG. 1, four force sensors are used, but the number of force sensors is three or more as long as information necessary for specifying the position where the pressing force is applied to the panel member can be obtained. Is optional.

  In the above description, the case where the force sensor unit of the present invention is applied to a touch panel input device has been described, but the force sensor unit of the present invention is a switch device whose output changes according to the operation amount, such as a slide switch, Naturally, it can be applied to a load measuring instrument for measuring a load.

  According to the present invention, even if the pressure receiving member is pressed strongly, the force sensor is not damaged, and the amount of change in the output of the force sensor when the pressing force is increased can be increased in proportion to the pressing force. .

DESCRIPTION OF SYMBOLS 1 Touch panel input device 3 Panel member 5 Base member 7 Force sensor unit 31 Touch panel 32 Frame 33 Side wall 34 Mounting hole 51 Base main body part 52 Flange part 71 Force sensor 72 Holding mechanism 73 First attachment member 73a Sensor attachment part 73b Fixing part 74 Second attachment member 74a Bias force applying portion 74b Fixing portion 77 Bias force applying means 78 Additional bias force applying means

Claims (8)

A pressure receiving member having a surface to which a pressing force is applied;
A base member facing the back surface of the pressure receiving member;
A force sensor unit that is used between the pressure receiving member and the base member with a predetermined interval between them, and is used in an apparatus including one or more force sensors that detect the pressing force;
A holding mechanism for holding the force sensor between the pressure receiving member and the base member;
The holding mechanism applies a predetermined bias force to the force sensor in a state where the pressing force is not applied to the surface of the pressure receiving member, and the pressing force is applied when the pressing force is applied to the surface. A force sensor unit configured to reduce the bias force in proportion to the height. The holding mechanism includes a sensor mounting portion that is positioned in a space between the pressure receiving member and the base member and to which the force sensor is attached, and is fixed to one member of the pressure receiving member and the base member. 1 attachment member;
A second attachment member provided with a bias force applying portion facing the sensor mounting portion with the force sensor interposed therebetween, and fixed to the other member of the pressure receiving member and the base member;
The force sensor according to claim 1, further comprising: a bias force applying unit that applies a bias force to the force sensor via the bias force applying unit in a state where the pressing force is not applied to the surface of the pressure receiving member. unit. The first attachment member has a fixing portion that is formed integrally with the sensor mounting portion and fixed to the base member,
The second attachment member has a fixed portion that is formed integrally with the bias force applying portion and fixed to the pressure receiving member,
The force sensor is located between the sensor attachment portion of the first attachment member and the bias force applying portion of the second attachment member;
The bias force applying means is disposed between the bias force applying portion of the second attachment member and the base member;
The biasing force applying means is deformable so as to be restored by the pressing force applied to the pressure receiving member, and when the pressing force is removed, the biasing force applying means restores the original shape and restores the pressure receiving member to the original position. The force sensor unit according to claim 2, wherein the force sensor unit is configured to be applied to the pressure receiving member.   Between the sensor attachment portion and the fixing portion of the second attachment member fixed to the pressure receiving member, the deformation is reversibly caused by the pressing force, and when the pressing force is removed, the original shape is obtained. The force sensor unit according to claim 3, further comprising an additional bias force applying unit that applies a restoring force to the pressure receiving member to restore and return the pressure receiving member to the original position.   The force sensor unit according to claim 4, wherein the first and second attachment members, the bias force applying unit, and the additional bias force applying unit are combined to form one force sensor unit. The fixed portion of the first attachment member includes a parallel portion extending in parallel with the sensor attachment portion, and a connecting portion that connects one end of the sensor attachment portion and one end of the parallel portion,
The fixing portion of the second attachment member includes a parallel portion extending in parallel with the bias force applying portion, and a connecting portion that connects one end of the bias force applying portion and one end of the parallel portion,
In the first and second attachment members, the sensor attachment portion and the bias force applying portion face each other, and the connection portion of the first attachment member and the connection portion of the second attachment member are parallel to each other. Combined to line up,
The bias force applying means is disposed between the sensor attachment portion of the first attachment member and the parallel portion of the second attachment member;
The biasing force applying means is deformable so as to be restored by the pressing force applied to the pressure receiving member, and when the pressing force is removed, the biasing force applying means restores the original shape and restores the pressure receiving member to the original position. The force sensor unit according to claim 3 , wherein the force sensor unit is configured to be applied to the pressure receiving member.   The force sensor unit according to any one of claims 2 to 6, wherein the bias force applying means is constituted by a spring or an elastic member. The force sensor unit according to claim 4, wherein the additional bias force applying unit is configured by a spring or an elastic member.

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