Load detection device

Abstract

Provided is a load detection device capable of reducing the number of irregularities on an input surface, ensuring ease of shear deformation of protrusions, and detecting a rotational load. The load detection device has a pressure detection unit, an elastic deformation unit, and an input unit arranged in this order in a first direction. The pressure detection unit has an array substrate, a sensor layer, a plurality of array electrodes arranged in each of a second direction and a third direction, and an elastic deformation unit has a plurality of first protrusions arranged in the second direction and the third direction. The first protrusions are disposed so as to overlap each of two or more array electrodes arranged in the second direction and two or more array electrodes arranged in the third direction, and the input section has a plurality of second protrusions arranged in the second direction and the third direction. The second protrusions are disposed so as to overlap each of at least two or more first protrusions arranged in the second direction and at least two or more first protrusions arranged in the third direction when viewed from the first direction.

Description

Technical Field

[0001] The utility model relates to a load detection device. Background Art

[0002] The load detection device is a device that detects a load (pressure) input perpendicularly to a detection surface and a load input in a direction parallel to the detection surface. Hereinafter, the direction parallel to the detection surface is referred to as a horizontal direction. The load detection device of the following patent document includes a pressure detection unit for detecting pressure and an elastic deformation unit overlapping the pressure detection unit. The pressure detection unit includes an array substrate provided with a plurality of array electrodes and a sensor layer opposite to the array electrodes. In addition, the elastic deformation unit has a plurality of protrusions (bumps). One protrusion is arranged across a plurality of array electrodes. The bottom surface of the protrusion is fixed to the pressure detection unit, and the load is input at the front end of the protrusion.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-200281 Utility Model Content

[0006] Issues to be solved by utility models

[0007] The load input surface of the load detection device becomes a concave-convex shape composed of multiple protrusions. When the number of the concave-convex is large, foreign matter and the like can easily invade between the protrusions, which is not preferred. In contrast, it is possible to consider increasing the protrusions and reducing the number of concave-convex. However, when the protrusions become larger, it is difficult to shear and deform when a load in the horizontal direction is input, and the detection sensitivity becomes poor. In addition, in the load detection device, it is expected that in addition to pressure or horizontal loads, rotational loads (loads in the rotational direction centered on an axis perpendicular to the input surface) can also be detected.

[0008] The utility model aims to provide a load detection device which can reduce the number of concavo-convexities of an input surface, ensure the ease of shear deformation of a protrusion, and detect a rotation load.

[0009] Means for solving problems

[0010] A load detection device of one embodiment of the present disclosure has a pressure detection unit, an elastic deformation unit, and an input unit arranged in sequence in a first direction. The pressure detection unit has an array substrate having a plurality of array electrodes arranged on a first surface facing the first direction, and a sensor layer opposite to the plurality of array electrodes. The plurality of array electrodes are arranged in each of a second direction intersecting the first direction and a third direction intersecting both the first direction and the second direction. The elastic deformation unit has a plurality of first protrusions arranged in the second direction and the third direction. The first protrusion is arranged to overlap with each of at least two or more array electrodes arranged in the second direction and at least two or more array electrodes arranged in the third direction when viewed from the first direction. The input unit has a plurality of second protrusions arranged in the second direction and the third direction. The second protrusion is arranged to overlap with each of at least two or more first protrusions arranged in the second direction and at least two or more first protrusions arranged in the third direction when viewed from the first direction.

[0011] In addition, the second protrusion of the load detection device is arranged to overlap with each of at least three or more first protrusions arranged in the second direction and at least three or more first protrusions arranged in the third direction when viewed from the first direction. Among at least nine or more first protrusions overlapping with one second protrusion when viewed from the first direction, ends of some of the first protrusions in the first direction are bonded to the second protrusion, and ends of the first protrusions in the first direction of the remaining first protrusions are not bonded to the second protrusion.

[0012] Furthermore, the rigidity of the second protrusion of the load detection device is higher than the rigidity of the first protrusion. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a perspective view schematically showing the load detection device according to the first embodiment.

[0014] Figure 2 Observed from the direction of the arrow Figure 1 A cross-sectional view taken along the line II-II shown.

[0015] Figure 3 : is a circuit diagram showing the circuit configuration of the pressure sensor according to the first embodiment.

[0016] Figure 4 Schematic diagram showing the correspondence between protrusions and individual detection areas in the first embodiment.

[0017] Figure 5This is a cross-sectional view when a load in a pressing direction is input to the first protrusion in the first embodiment.

[0018] Figure 6 This is a cross-sectional view when a horizontal load is input to the protrusion in the first embodiment.

[0019] Figure 7 1 is a schematic diagram showing the correspondence relationship between the second protrusions and the first protrusions in the first embodiment.

[0020] Figure 8 This is a schematic cross-sectional view of a state where a horizontal load acts on the second protrusion in the first embodiment.

[0021] Fig. 9 This is a schematic diagram obtained by planarly viewing a state where a rotational load acts on the second protrusion in the first embodiment.

[0022] Fig.10 1 is a schematic diagram showing the correspondence relationship between the second protrusions and the first protrusions in the load detection device according to the second embodiment.

[0023] Fig.11 Yes Fig.10 A schematic diagram showing the cross section of line XI-XI and the observation from the direction of the arrow.

[0024] Fig.12 This is a schematic cross-sectional view of a state where a horizontal load acts on the second protrusion in the second embodiment.

[0025] Fig.13 This is a schematic diagram obtained by planarly viewing a state where a rotational load acts on the second protrusion in the second embodiment.

[0026] Fig.14 This is a cross-sectional view of the pressure detection portion of Modification 1 cut in the stacking direction.

[0027] Fig.15 This is a cross-sectional view of the pressure detection portion of Modification 2 cut in the stacking direction.

[0028] Fig.16 This is a cross-sectional view of the pressure detection portion of Modification 3 in a state before the pressure input is cut off in the stacking direction.

[0029] Fig.17 This is a cross-sectional view of the pressure detection portion of Modification 3 in a state where pressure input is cut off in the stacking direction.

[0030] Fig.18 This is a cross-sectional view of the pressure detection portion of Modification 4 in a state before the pressure input is cut off in the stacking direction.

[0031] Description of Reference Numerals

[0032] 1, 1B, 1C, 1D, 1E pressure detection unit

[0033] 1a Detection surface

[0034] 2 Detection area

[0035] 3 Surrounding areas

[0036] 4 Individual detection areas

[0037] 10 Array substrate

[0038] 13 Driver transistor

[0039] 20 Array Electrodes

[0040] 30, 30D, 30E sensor layer

[0041] 40 Common electrode

[0042] 45 Intermediate electrode

[0043] 50 layers of protection

[0044] 60 Elastic deformation part

[0045] 61 First protrusion

[0046] 80 Input section

[0047] 81 Second protrusion

[0048] 82 front end

[0049] 83 front face

[0050] 84 Bottom

[0051] 100, 100A load detection device DETAILED DESCRIPTION

[0052] The mode (implementation mode) for implementing the load detection device disclosed in the present invention is described in detail with reference to the accompanying drawings. The utility model disclosed in the present invention is not limited by the contents described in the following implementation modes. In addition, the constituent elements described below include elements that can be easily thought of by a person skilled in the art and elements that are essentially the same. Moreover, the constituent elements described below can be appropriately combined. It should be noted that the disclosure is only an example after all, and the technical solutions that can be easily thought of by a person skilled in the art and that maintain the appropriate changes to the purpose of the utility model are of course included in the scope of the present invention. In order to make the description clearer, the drawings sometimes schematically show the width, thickness, shape, etc. of each part compared to the actual solution, but this is only an example and does not limit the interpretation of the present invention. In addition, in this specification and each figure, for the figures that have appeared, the same reference numerals are sometimes given to the constituent elements that are the same as the aforementioned elements, and detailed descriptions are appropriately omitted.

[0053] In addition, in the present specification and claims, when expressing a scheme of configuring another structure on a certain structure, when it is simply recorded as "on...", unless otherwise stated, it includes both a case where the other structure is configured directly above the certain structure in a manner of contacting the certain structure and a case where the other structure is further configured above the certain structure via another structure.

[0054] (Implementation Method 1)

[0055] Figure 1 Schematically shows a perspective view of the load detection device of Embodiment 1. Figure 1 As shown, the load detection device 100 includes a pressure detection unit 1 , an elastic deformation unit 60 disposed on one surface (detection surface 1 a ) of the pressure detection unit 1 , and an input unit 80 disposed in a direction opposite to the pressure detection unit 1 as viewed from the elastic deformation unit 60 .

[0056] In the following description, the direction in which the pressure detection unit 1, the elastic deformation unit 60, and the input unit 80 are arranged is referred to as the stacking direction. The direction in the stacking direction in which the input unit 80 is arranged and viewed from the pressure detection unit 1 is referred to as the first direction X1. The direction opposite to the first direction X1 is referred to as the pushing direction X2. Observation from the pushing direction X2 is referred to as a top view. In addition, the direction parallel to one surface (detection surface 1a) of the pressure detection unit 1 is referred to as a horizontal direction.

[0057] The load detection device 100 detects the load (pressure) in the pushing direction X2, the load in the horizontal direction, and the load in the rotation direction (see Figure 1 Arrow H2). Figure 1As shown, the load in the rotation direction refers to the load H2 in the rotation direction centered on the imaginary line H1 extending in the stacking direction. In addition, the surface of the load detection device 100 arranged in the first direction X1 becomes the input surface 90 of the load. Therefore, the input surface 90 is composed of the input part 80.

[0058] The pressure detection unit 1 is a flat plate-shaped device with a small thickness in the stacking direction and extending in the horizontal direction. The pressure detection unit 1 has a detection surface 1a facing the first direction X1. The detection surface 1a of the pressure detection unit 1 is divided into a detection area 2 located in the center of the detection surface 1a and capable of detecting pressure and a peripheral area 3 surrounding the outside of the detection area 2.

[0059] The detection area 2 is formed to be rectangular when viewed from above. Therefore, the outer frame L of the detection area 2 has a pair of long sides 2a and a pair of short sides 2b. Hereinafter, the direction parallel to the long side 2a is referred to as the second direction Y. The direction parallel to the short side 2b is referred to as the third direction Z. The detection area 2 is divided into a plurality of areas in the second direction Y and the third direction Z. The divided areas are referred to as separate detection areas 4.

[0060] Figure 2 Observed from the direction of the arrow Figure 1 The cross-sectional view is obtained by cutting the cross section at the II-II line shown in FIG. Figure 2 As shown, the pressure detection unit 1 has an array substrate 10, a sensor layer 30, a common electrode 40 and a protection layer 50 sequentially arranged in a first direction X1. In addition, the array substrate 10 has a substrate 11 and an array layer 12 sequentially arranged in the first direction X1.

[0061] The substrate 11 is a base material of the array layer 12 and has insulating properties. The substrate 11 is formed of a material that is difficult to deform even when a load is applied to the pressure detection unit 1, and examples thereof include a glass substrate and a resin substrate.

[0062] The array layer 12 is stacked on the substrate 11 and integrated with the substrate 11. Although not specifically shown in the figure, the array layer 12 has a plurality of insulating layers stacked in the stacking direction. A plurality of driving transistors (switching elements) 13 are provided inside the array layer 12. The driving transistor 13 includes a semiconductor layer 13a, a gate insulating film 13b, a gate electrode 13c, a drain electrode 13d, and a source electrode 13e. The driving transistor 13 is arranged within the range of the detection area 2. The driving transistor 13 is provided one by one with respect to a single detection area 4. Therefore, the plurality of driving transistors 13 are arranged in the second direction Y and the third direction Z corresponding to the single detection area 4.

[0063] The array layer 12 has a first surface 12a facing the first direction X1. A plurality of array electrodes 20 are provided on the first surface 12a. The array electrodes 20 are made of a metal material such as ITO (Indium Tin Oxide). The array electrodes 20 are formed to be rectangular in plan view (see FIG. 2 ). Figure 4 ). The array electrodes 20 are arranged within the range of the detection area 2. The array electrodes 20 are arranged one by one with respect to a single detection area 4. Therefore, the plurality of array electrodes 20 are arranged in the second direction Y and the third direction Z corresponding to the single detection area 4 (refer to Figure 1 ). In a plan view, the array electrode 20 is located in the center of the individual detection area 4 (refer to Figure 4 ) The array electrode 20 is connected to the source electrode 13 e of the driving transistor 13 .

[0064] The array layer 12 includes various structures for driving the driving transistor 13. Specifically, the array layer 12 has a connection portion 7 (see Figure 1 )、gate line driving circuit 8 (refer to Figure 1 )、Signal line selection circuit 9 (refer to Figure 1 ), gate line 14 (refer to Figure 3 ) and signal line 15 (refer to Figure 3 ).

[0065] like Figure 1 As shown, the connection part 7, the gate line driving circuit 8 and the signal line selection circuit 9 are arranged in the peripheral area 3. The connection part 7 is used to connect to the driver IC (Integrated Circuit) arranged outside the pressure detection part 1. It should be noted that the driver IC in the present disclosure can be installed as a COF (Chip On Film) on a flexible printed substrate or a rigid substrate connected to the connection part 7. Alternatively, the driver IC can be installed in the peripheral area 3 as a COG (Chip On Glass).

[0066] The gate line driving circuit 8 drives the plurality of gate lines 14 based on various control signals from the driving IC (see Figure 3 The gate line drive circuit 8 selects a plurality of gate lines 14 in sequence or simultaneously and supplies a gate drive signal to the selected gate lines 14. The signal line selection circuit 9 selects a plurality of signal lines 15 in sequence or simultaneously (see Figure 3 ) of the switch circuit. The signal line selection circuit 9 is, for example, a multiplexer. The signal line selection circuit 9 connects the selected signal line 15 to the driver IC based on a selection signal supplied from the driver IC.

[0067] Figure 3 1 is a circuit diagram showing the circuit structure of the pressure sensor according to Embodiment 1. Figure 3As shown, one end of the gate line 14 is connected to the gate line driving circuit 8 and extends in the third direction Z in the detection area 2. In addition, in the detection area 2, a plurality of gate lines 14 are arranged in the second direction Y. One end of the signal line 15 is connected to the signal line selection circuit 9 and extends in the second direction Y in the detection area 2. In addition, in the detection area 2, a plurality of signal lines 15 are arranged in the third direction Z.

[0068] The gate electrode 13c of the driving transistor 13 is connected to the gate line 14. The drain electrode 13d of the driving transistor 13 is connected to the signal line 15. Therefore, when the gate line 14 is scanned, the driving transistor 13 is turned on. As a result, the electric signal (current value) input to the array electrode 20 is output to the signal line 15 via the driving transistor 13. Then, the electric signal (current value) is sent from the signal line 15 to the driving IC.

[0069] In addition, although not particularly shown, the array layer 12 has common wiring extending along the peripheral region 3. The common wiring is a wiring for supplying current to the common electrode 40. The common wiring is connected to the driver IC via the connection portion 7, and a certain amount of current is supplied from the driver IC.

[0070] like Figure 2 As shown, the protective layer 50 extends in the horizontal direction and has insulating properties. A frame-shaped spacer not shown is provided in the peripheral area 3 of the first surface 12a of the array substrate 10. The protective layer 50 is supported by the spacer not shown. Thus, the protective layer 50 is configured separately in the first direction X1 relative to the array substrate 10. In addition, the protective layer 50 has a detection surface 1a facing the first direction X1 and an opposite surface 51 facing the pushing direction X2 and opposite to the array electrode 20.

[0071] The common electrode 40 is formed of a metal material such as ITO (Indium Tin Oxide). The common electrode 40 is a whole-surface film formed on the opposite surface 51 of the protective layer 50, and is provided in the entire area of ​​the detection area 2. The common electrode 40 is connected to a common wiring (not shown) by a wiring not shown in the figure. Therefore, a certain amount of current is supplied from the driver IC to the common electrode 40.

[0072] The sensor layer 30 is provided on the surface 41 of the common electrode 40 in the pushing direction X2. The sensor layer 30 is provided in the entire area of ​​the detection area 2. The sensor layer 30 is formed of a conductive resin. A plurality of convex portions 30a are provided on the surface of the sensor layer 30 in the pushing direction X2. Each convex portion 30a is separated from the array electrode 20 and the first surface 12a of the array layer 12. Therefore, a gap is generated between the array electrode 20 and the first surface 12a and the sensor layer 30.

[0073] The elastic deformation part 60 is formed of a material capable of elastic deformation. Therefore, when a load is input to the elastic deformation part 60, it is deformed, and when the load is removed, it returns to its original shape. As representative materials forming the elastic deformation part 60, rubber, resin, etc. can be cited, but the present disclosure is not limited thereto.

[0074] like Figure 1 As shown, the elastic deformation portion 60 of the first embodiment has a plurality of first protrusions 61. The first protrusions 61 are formed in a quadrangular column shape. The first protrusions 61 are arranged in the second direction Y and the third direction Z. Figure 1 In order to make the detection area 2 easier to see, some of the first protrusions 61 are not shown.

[0075] The elastic deformation portion 60 of this embodiment is composed of only a plurality of first protrusions 61. In other words, the plurality of first protrusions 61 are independent of each other. Figure 2 As shown, the end of the first protrusion 61 in the first direction X1 is a front end 62. The first protrusion 61 has a front end surface 63 facing the first direction X1, a bottom surface 64 facing the pressing direction X2, and four side surfaces 65.

[0076] The bottom surface 64 is fixed to the detection surface 1a of the pressure detection unit 1. The fixing method may include bonding and welding, but the present disclosure is not limited to these methods. Two of the four side surfaces 65 face the second direction Y, and the remaining two face the third direction Z. Therefore, the side surfaces 65 of two first protrusions 61 adjacent to each other in the second direction Y or the third direction Z face each other.

[0077] like Figure 1 As shown, the first protrusion 61 is separated from the other first protrusions 61 arranged in each of the second direction Y and the third direction Z. The cross-sectional shape of the first protrusion 61 cut in the stacking direction is a quadrilateral. It should be noted that the cross-sectional shape of the first protrusion 61 in the stacking direction of the present embodiment is a quadrilateral, but the present disclosure is not limited thereto, and for example, the cross-sectional shape may also be a trapezoid.

[0078] Figure 4 Schematic diagram showing the correspondence between protrusions and individual detection areas in Embodiment 1. Figure 4 As shown, when viewed from above, the first protrusion 61 is arranged across a plurality of individual detection areas 4. Therefore, when a load is input to one first protrusion 61, the load acts (is transmitted) on four individual detection areas 4. Hereinafter, the four individual detection areas 4 are summarized as one, referred to as a load detection area 5. In addition, the bottom surface 64 has four sides 66. Each side 66 overlaps with the array electrode 20 when viewed from above.

[0079] Figure 52 is a cross-sectional view of a case where a load in a pushing direction is input to the first protrusion in Embodiment 1. Figure 5 In the figure, the second protrusion 81 is not shown. According to the above structure, Figure 5 As shown in FIG. 1 , when pressure A (load in the pushing direction X2) is input to the front end surface 63 of the first protrusion 61, the first protrusion 61 moves in the pushing direction X2. In addition, the load is transmitted from the first protrusion 61 to the common electrode 40 and the sensor layer 30, and the common electrode 40 and the sensor layer 30 also move in the pushing direction X2. Then, the convex portion 30a of the sensor layer 30 contacts the array electrode 20.

[0080] As a result, the array electrode 20 is electrically connected to the common electrode 40, and current flows from the common electrode 40 to the array electrode 20 (see Figure 5 In addition, the current flowing to the array electrode 20 is transmitted to the driver IC via the signal line 15. The driver IC receives the detection signal (current) and detects that the load is input to the individual detection area 4.

[0081] In addition, when the pressure A input to the first protrusion 61 is large, the number of convex portions 30a in contact with the array electrode 20 increases, and the contact area with the array electrode 20 increases. In addition, the convex portions 30a are pressed and flattened by the array electrode 20, thereby increasing the contact area with the array electrode 20. For this reason, the amount of current input to the array electrode 20 increases in proportion to the increase in the pressure A (increase in the contact area). Then, the driver IC detects the magnitude of the load acting on the individual detection area 4 based on the magnitude of the received current value.

[0082] In addition, when the load acting on the first protrusion 61 is a pressure (a load in the pushing direction X2), the pressure acting on the first protrusion 61 is evenly dispersed in the four individual detection areas 4. In other words, the load (current value) detected in each of the four individual detection areas 4 included in the load detection area 5 becomes equal. Therefore, when the amount of current detected from each of the four individual detection areas 4 included in the load detection area 5 is equal, the driver IC determines that the direction of the load acting on the first protrusion 61 is the pushing direction X2.

[0083] Figure 6 2 is a cross-sectional view of a case where a horizontal load is input to the protrusion in Embodiment 1. Figure 6 The second protrusion 81 is not shown in the figure. Next, the load input to the first protrusion 61 in the horizontal direction (see Figure 6 However, the load in the horizontal direction described in this specification is set as the load in the third direction Z (hereinafter referred to as horizontal load B).

[0084] It should be noted that the load component in the pushing direction X2 is included in the horizontal load B. Therefore, the load in the pushing direction X2 acts on the detection surface 1a from the bottom surface 64 of the first protrusion 61. As a result, the sensor layer 30 to which each of the four individual detection areas 4 belongs contacts the array electrode 20, and the current flows from the common electrode 40 to the array electrode 20. For this reason, even when the horizontal load B is input to the first protrusion 61, the load in the pushing direction X2 is detected from each of the individual detection areas 4.

[0085] like Figure 6 As shown in FIG. 1 , when a horizontal load B is input to the front end portion 62 of the first protrusion 61, the front end portion 62 of the first protrusion 61 moves in the direction of the load (the third direction Z). On the other hand, the bottom surface 64 of the first protrusion 61 is fixed, and the first protrusion 61 itself does not move. Therefore, the first protrusion 61 is shear-deformed, and the cross-sectional shape of the first protrusion 61 becomes a parallelogram.

[0086] When the cross-sectional shape of the first protrusion 61 is a parallelogram, shear stress is generated on the first protrusion 61. Therefore, among the four sides of the front end surface 63, the side ( Figure 6 The side 63a of the bottom surface 64 and the side 66 of the bottom surface 64 located in the opposite direction to the horizontal load B (refer to Figure 6 The tensile stress (arrow B1) in the diagonal direction acts between the edges 66a and 66b. As a result, the edges (refer to Figure 6 In the vicinity of the edge 66a), the load in the pushing direction X2 acting from the bottom surface 64 on the detection surface 1a is reduced.

[0087] In addition, among the four sides of the front end surface 63, the side ( Figure 6 The side 63b of the bottom surface 64 and the side ( Figure 6 The compressive stress (arrow B2) acts on the diagonal line between the edges 66b of the bottom surface 64. Figure 6 In the vicinity of the edge 66b), the load in the pushing direction X2 acting from the bottom surface 64 on the detection surface 1a increases.

[0088] For this reason, the load in the pushing direction X2 acting from the bottom surface 64 on the detection surface 1a varies within the bottom surface 64, becoming larger in the direction of the horizontal load B and becoming smaller in the direction opposite to the horizontal load B. Thus, the load in the pushing direction X2 acting from the bottom surface 64 of the first protrusion 61 on the detection surface 1a varies.

[0089] Therefore, when the horizontal load B is input, the contact area between the sensor layer 30 and the array electrode 20 is larger in the individual detection region 4 to which the side 66b belongs than in the individual detection region 4 to which the side 66a belongs. As a result, the amount of current input to the array electrode 20 in the individual detection region 4 to which the side 66b belongs (refer to Figure 6 The amount of current input to the array electrode 20 in the individual detection area 4 to which the edge 66a belongs (see arrow B3) is greater than the amount of current input to the array electrode 20 in the individual detection area 4 to which the edge 66a belongs (see Figure 6 arrow B4).

[0090] Therefore, when the current amounts detected from each of the four individual detection areas 4 included in the load detection area 5 are not uniform, the driver IC determines that the direction of the load input to the first protrusion 61 is the horizontal direction. In addition, the driver IC determines the direction in which the individual detection area 4 with a larger current amount is arranged, observing the individual detection area 4 with a smaller current amount detected from among the four individual detection areas 4, as the direction of the horizontal load B.

[0091] As the horizontal load B increases, the load acting from the bottom surface 64 on the detection surface 1a in the pressing direction X2 varies. Therefore, the driver IC calculates the difference (variation) in the current amount detected from each individual detection area 4 and calculates the magnitude of the horizontal load B.

[0092] Furthermore, when the load input to the first protrusion 61 is in the horizontal direction, the closer to the four sides 66 of the bottom surface 64, the greater the change in the push load acting on the detection surface 1a from the bottom surface 64 of the first protrusion 61. In other words, the closer to the four sides 66 of the bottom surface 64, the greater the deviation in the load caused by the shear stress. In this embodiment, the four sides 66 of the bottom surface 64 overlap with the array electrode 20 (see Figure 4 ), the sensitivity of detecting the load in the horizontal direction is high. Next, the input unit 80 is described.

[0093] like Figure 1 As shown, the input part 80 has a plurality of second protrusions 81. The second protrusions 81 are formed in a quadrangular prism shape. Therefore, the cross-sectional shape formed by cutting the second protrusions 81 in the stacking direction is a quadrangular shape. The second protrusions 81 are arranged in the second direction Y and the third direction Z. It should be noted that Figure 1 In order to make the detection area 2 easier to see, some of the second protrusions 81 are not shown.

[0094] The input portion 80 of this embodiment is composed only of a plurality of second protrusions 81. In other words, the plurality of second protrusions 81 are independent of each other. Figure 2As shown, the end of the second protrusion 81 in the first direction X1 becomes the front end 82. The load is input to the front end 82. In addition, the second protrusion 81 has a front end face 83 facing the first direction X1, a bottom face 84 facing the pushing direction X2, and four side faces 85. The front end face 83 and the bottom face 84 are respectively formed in a square (quadrilateral). The input surface 90 is composed of the front end faces 83 of the plurality of second protrusions 81. The bottom face 84 is fixed to the front end face 63 of the first protrusion 61. The fixing method can be bonding and welding, but the present disclosure is not limited to these methods.

[0095] like Figure 1 As shown, two of the four side surfaces 85 face the second direction Y, and the remaining two face the third direction Z. Therefore, the side surfaces 85 of two second protrusions 81 adjacent to each other in the second direction Y or the third direction Z face each other. The second protrusions 81 are separated from the other second protrusions 81 arranged in the second direction Y and the third direction Z. Therefore, when a load in the horizontal direction is input to the second protrusions 81, it is difficult for them to contact with the other second protrusions 81.

[0096] Figure 7 Schematic diagram showing the corresponding relationship between the second protrusion and the first protrusion in Embodiment 1. Figure 7 As shown, in a plan view, the second protrusion 81 is arranged across a plurality of load detection regions 5. Therefore, when a load is input to one second protrusion 81, the load acts (is transmitted) on four first protrusions 61 arranged in each of the four load detection regions 5.

[0097] It should be noted that the input portion 80 is formed of a material that is not easily elastically deformed. More preferably, the input portion 80 is formed of a material with higher rigidity than the first protrusion. Thus, the input portion 80 is prevented from being deformed by a load and the load transmitted to the first protrusion 61 is reduced.

[0098] Next, an operation example of the load detection device of Embodiment 1 is described. When the load acting on the second protrusion 81 is a pressure (a load in the pushing direction X2), the load is evenly transmitted from the second protrusion 81 to the four first protrusions 61 connected to the second protrusion 81. Therefore, pressure is detected in each of the four load detection areas 5.

[0099] Figure 8 Schematic diagram of the cross-section of the horizontal load acting on the second protrusion in Embodiment 1. Figure 8As shown, when the load acting on the second protrusion 81 is a horizontal load C, the second protrusion 81 moves in the direction of the horizontal load C. It should be noted that the second protrusion 81 has a high rigidity and does not shear and deform. The front end portion 62 of each of the four first protrusions 61 connected to the second protrusion 81 moves in the direction of the horizontal load C. As a result, each of the four first protrusions 61 is shear-deformed, and the horizontal load C is detected in each of the four load detection areas 5.

[0100] Fig. 9 1 is a schematic diagram obtained by looking down on the case where the rotational load acts on the second protrusion in the first embodiment. Next, the case where the load acting on the second protrusion 81 is a rotational load is described. In this description, the load is clockwise when viewed from above (see Fig. 9 In the following description, regarding the second direction Y, the direction in which the connection portion 7 is arranged when viewed from the detection area 2 is referred to as the lower side Y1, and the opposite direction of the lower side Y1 is referred to as the upper side Y2. In addition, regarding the third direction Z, the direction in which the right hand is arranged toward the upper side Y2 with reference to the detection area 2 is referred to as the right side Z1, and the opposite side of the right side Z1 is referred to as the left side.

[0101] like Fig. 9 As shown, when the rotation load D is input to the second protrusion 81, the second protrusion 81 rotates clockwise around the center O81 of the second protrusion 81 when viewed from above. Therefore, the first protrusion 61A arranged on the upper left side among the four first protrusions 61 receives a load caused by the front end portion 62 moving toward the upper side Y2 (see arrow D1). The first protrusion 61B arranged on the upper right side among the four first protrusions 61 receives a load caused by the front end portion 62 moving toward the right side Z1 (see arrow D2). The first protrusion 61C arranged on the lower right side among the four first protrusions 61 receives a load caused by the front end portion 62 moving toward the lower side Y1 (see arrow D3). The first protrusion 61D arranged on the lower left side among the four first protrusions 61 receives a load caused by the front end portion 62 moving toward the left side Z2 (see arrow D4). Therefore, horizontal loads in different directions are input to each of the four separate detection areas 4 (see arrows D1, D2, D3, and D4). According to the above scheme, when a horizontal load in a different direction is input to each of the four load detection regions 5 , the driver IC determines the load input to the second protrusion 81 as a rotation load.

[0102] Next, the effect of the load detection device 100 of embodiment 1 is described. According to the load detection device 100 of this embodiment, the input surface 90 is composed of a plurality of second protrusions 81. That is, the number of depressions and projections is reduced compared to the case where the input surface 90 is composed of the first protrusion 61. Therefore, it is difficult for foreign matter to invade between the protrusions (between the second protrusions 81). In addition, in this embodiment, the first protrusion 61 is not enlarged, but is the same size as before. Therefore, the ease of shear deformation of the first protrusion 61 is ensured. And, according to this embodiment, it is possible to detect a rotational load.

[0103] The load detection device 100 of the first embodiment is described above. The load detection device of the present disclosure can be configured such that after the second protrusion 81 moves a specified amount in the horizontal direction, it contacts with other second protrusions 81 arranged next to it. When contacting with other second protrusions 81, the movement amount of the second protrusion 81 is limited to be small, and shear deformation occurs on the first protrusion 61, so that the load in the horizontal direction and the rotational direction can be detected. Therefore, it can be that after the second protrusion 81 moves a specified amount in the horizontal direction, it contacts with other second protrusions 81 arranged next to it. Next, other embodiments of the load detection device are described. In addition, in the following description, the differences from the first embodiment are mainly described.

[0104] (Implementation Method 2)

[0105] Fig.10 1 is a schematic diagram showing the correspondence relationship between the second protrusions and the first protrusions in the load detection device according to the second embodiment. Fig.11 Yes Fig.10 The cross section of the XI-XI line is schematically shown and viewed from the direction of the arrow. Fig.10 , Fig.11 As shown, the second protrusion 181 (input part 180) of the load detection device 100A of embodiment 2 is different from that of embodiment 1 in that it is configured to overlap with a total of 9 first protrusions 161 (elastic deformation parts 160) in 3 rows in each of the second direction Y and the third direction Z when viewed from above.

[0106] In addition, a part of the first protrusions 161 among the nine first protrusions 161 is bonded to the second protrusion 181. Specifically, the first protrusion 161A disposed on the upper left, the first protrusion 161B disposed on the upper right, the first protrusion 161C disposed on the lower right, and the first protrusion 161D disposed on the lower left among the nine first protrusions 161 are bonded to the second protrusion 181 at their respective front ends. Hereinafter, the first protrusion 161 bonded to the second protrusion 181 among the first protrusions 161 is referred to as a bonding protrusion 261. Therefore, when the second protrusion 181 moves in the horizontal direction, the front end of the bonding protrusion 261 moves in the horizontal direction in a following manner. In addition, when the second protrusion 181 moves in the pressing direction X2, the bonding protrusion 261 receives a load in the pressing direction X2.

[0107] Hereinafter, the first protrusion 161 that is not bonded to the second protrusion 181 among the first protrusions 161 is referred to as a non-bonded protrusion 361. The front end surface 163 of the non-bonded protrusion 361 abuts against the bottom surface 184 of the second protrusion 181. Therefore, even if the second protrusion 181 moves in the horizontal direction, the front end surface 163 of the non-bonded protrusion 361 does not follow the second protrusion 181. In addition, when the second protrusion 181 moves in the pressing direction X2, the non-bonded protrusion 361 receives a load in the pressing direction X2.

[0108] Next, an operation example of the load detection device of Embodiment 2 is described. When the load acting on the second protrusion 181 is a pressure (a load in the pushing direction X2), the pushing load is transmitted from the second protrusion 181 to each of the nine first protrusions 161. Therefore, pressure is detected in each of the nine load detection regions 5.

[0109] Fig.12 Schematic diagram of the cross-section of the horizontal load acting on the second protrusion in Embodiment 2. Fig.12 As shown, when the horizontal load E is input to the second protrusion 181, the second protrusion 181 moves in the direction of the horizontal load E. As a result, the front end of the bonding protrusion 261 moves in the direction of the horizontal load E, and the bonding protrusion 261 is shear-deformed. Therefore, the horizontal load E is detected in each of the load detection areas 5 to which the bonding protrusion 261 belongs.

[0110] On the other hand, the tip of the unbonded protrusion 361 does not move in the direction of the horizontal load E. That is, the unbonded protrusion 361 does not deform by shearing. Therefore, in the load detection area 5 to which the unbonded protrusion 361 belongs, no horizontal load is detected.

[0111] On the other hand, when the load input to the second protrusion 181 includes both the load in the pushing direction X2 and the horizontal load, the second protrusion 181 moves in the pushing direction X2 and also moves in the direction of the horizontal load. Therefore, the unbonded protrusion 361 is pushed in the pushing direction X2 by the second protrusion 181. Moreover, the load in the pushing direction X2 is detected in each of the load detection areas 5 to which the unbonded protrusion 361 belongs. In addition, along with the horizontal movement of the second protrusion 181, the front end of the bonding protrusion 261 moves in the direction of the horizontal load. Then, the bonding protrusion 261 is shear-deformed, and the horizontal load is detected in each of the load detection areas 5 to which the bonding protrusion 261 belongs.

[0112] Fig.13 Schematic diagram obtained by looking down at the situation where the rotation load acts on the second protrusion in Embodiment 2. Fig.13 As shown, when a rotation load F in a clockwise direction with the center O181 of the second protrusion 181 as the center acts on the second protrusion 181, the second protrusion 181 rotates in a clockwise direction with the center O181 as the center. As a result, the bonding protrusion 261 is shear-deformed. In detail, the first protrusion 161A is subjected to a load in which the front end portion moves toward the upper side Y2 (see arrow F1). The first protrusion 161B is subjected to a load in which the front end portion moves toward the right side Z1 (see arrow F2). The first protrusion 161C is subjected to a load in which the front end portion moves toward the lower side Y1 (see arrow F3). The first protrusion 161D is subjected to a load in which the front end portion moves toward the left side Z2 (see arrow F4). Therefore, horizontal loads in different directions are detected in each of the load detection areas 5 to which the four bonding protrusions 261 belong.

[0113] In addition, in the case where the load input to the second protrusion 181 is the rotation load F, the unbonded protrusion 361 is not pushed from the second protrusion 181. Therefore, in the load detection area 5 to which the unbonded protrusion 361 belongs, no load is detected. On the other hand, in the case where the load input to the second protrusion 181 includes a load in the pushing direction X2 in addition to the rotation load F, the unbonded protrusion 361 receives the load in the pushing direction X2 from the second protrusion 181. Therefore, pressure is detected in each of the load detection areas 5 to which the unbonded protrusion 361 belongs.

[0114] As described above, according to the second embodiment, when the horizontal load and the rotational load are detected, the pressure (the load in the pressing direction X2 ) included in the horizontal load and the rotational load can also be detected.

[0115] Embodiment 1 and Embodiment 2 are described above, and the present disclosure is not limited to the above embodiments. For example, the input portion of the present embodiment is only composed of the second protrusions, and the input portion may also have, in addition to the second protrusions, a plurality of third protrusions arranged in the first direction relative to the second protrusions and arranged across the plurality of second protrusions. In other words, the number of protrusions overlapping in the stacking direction in the input portion only needs to be at least one level.

[0116] In addition, the second protrusion in the embodiment is a quadrangular prism, but it may be a polygonal prism or a circular column, and the shape of the second protrusion is not limited.

[0117] In addition, in the embodiment, one first protrusion 61 spans and overlaps four individual detection areas 4, but one first protrusion 61 may be arranged in three rows in each of the second direction Y and the third direction Z, and overlaps a total of nine individual detection areas 4. Therefore, in the present disclosure, the number of individual detection areas 4 that overlap with one first protrusion 61 in a plan view is not particularly limited.

[0118] In addition, gaps are provided between the plurality of first protrusions, but the present disclosure may also fill the gaps. However, in order to make the protrusions (protrusions) easily deformable, the material filling the gaps is preferably a material with low rigidity.

[0119] In the embodiment, the array electrodes 20 and the common electrodes 40 are arranged so as to face each other with the sensor layer 30 interposed therebetween, but the present disclosure is not limited thereto. Modifications 1 and 2 using other configuration examples will be described below.

[0120] (Variant 1)

[0121] Fig.14 : is a cross-sectional view obtained by cutting the pressure detection unit of Modification 1 in the stacking direction. The array electrode 20 and the common electrode 40 of the pressure detection unit 1B of Modification 1 are arranged on the first surface 12a of the array substrate 10. Therefore, the array electrode 20 and the common electrode 40 are arranged in the horizontal direction. In the case of input pressure, the sensor layer 30 contacts each of the array electrode 20 and the common electrode 40, and the current flows from the common electrode 40 to the array electrode 20.

[0122] (Variant 2)

[0123] Fig.15: is a cross-sectional view obtained by cutting the pressure detection portion of Modified Example 2 in the stacking direction. The pressure detection portion 1C of Modified Example 2 includes an array electrode 20, a common electrode 40, and an intermediate electrode 45. As in Modified Example 1, the array electrode 20 and the common electrode 40 are arranged on the first surface 12a of the array substrate 10. The intermediate electrode 45 is arranged between the sensor layer 30 and the protective layer 50. Then, in the case of input pressure, the sensor layer 30 contacts each of the array electrode 20 and the common electrode 40. As a result, after the current flows from the common electrode 40 to the intermediate electrode 45, the current flows from the intermediate electrode 45 to the array electrode 20.

[0124] In addition, the sensor layer 30 of the embodiment is formed of a conductive resin having the protrusions 30a on the surface in the pressing direction X2, but the present disclosure is not limited thereto. Modifications 3 and 4 using other sensor layers will be described below.

[0125] (Variant 3)

[0126] Fig.16 This is a cross-sectional view of the pressure detection portion of Modification 3 in a state before the pressure input is cut off in the stacking direction. Fig.17 2 is a cross-sectional view of the pressure detection unit of Modification 3 obtained in a state where the pressure input is cut off in the stacking direction. Fig.16 As shown, the sensor layer 30D of the pressure detection unit 1D of Modification 3 is made of conductive resin. The surface 33 of the sensor layer 30D in the pressing direction X2 is formed flat in the horizontal direction and does not contact the array electrode 20 .

[0127] like Fig.17 As shown in FIG. 1 , when pressure is input, the sensor layer 30D moves in the pushing direction X2 and contacts the array electrode 20. As a result, current flows from the common electrode 40 to the array electrode 20. In addition, when the pressure increases, the contact area between the sensor layer 30D and the array electrode 20 increases. Therefore, the amount of current flowing from the common electrode 40 to the array electrode 20 also increases.

[0128] (Variant 4)

[0129] Fig.18 2 is a cross-sectional view of the pressure detection portion of Modification 4 before the pressure input is cut off in the stacking direction. Fig.18 As shown, the sensor layer 30E of the pressure detection unit 1E of Modification 4 contains conductive particles 36 inside the insulating resin. The surface of the sensor layer 30E in the pressing direction X2 contacts the array electrode 20 and the first surface 12a of the array substrate 10.

[0130] When the sensor layer 30E is in a state where no pressure is applied, that is, in a state where no deformation occurs, the particles 36 are separated and in an insulating state. When pressure is applied to the sensor layer 30E, the particles 36 come into contact with each other. As a result, the resistance value of the sensor layer 30E decreases, and the common electrode 40 is electrically connected to the array electrode 20. Then, current flows from the common electrode 40 to the array electrode 20. In addition, when the pressure increases, the number of particles 36 that come into contact with each other increases, and the resistance value of the sensor layer 30E further decreases. As a result, the amount of current flowing from the common electrode 40 to the array electrode 20 also increases.

[0131] In addition, the length of the second protrusion in the stacking direction may not be uniform. In other words, the length of the protrusion and the protrusion portion in the stacking direction may be appropriately changed. In addition, the protrusion and the protrusion portion may not be formed using all the same materials. In other words, protrusions (or protrusion portions) formed from different materials may be mixed. In addition, the front end face of the second protrusion disclosed in the present invention is not limited to a plane, and in order to increase the friction coefficient, it may be set to a concave or protruding shape, without particular limitation.

Claims

1. A load detection device, wherein: It has a pressure detection unit, an elastic deformation unit, and an input unit arranged in sequence in a first direction, The pressure detection unit has: An array substrate having a plurality of array electrodes disposed on a first surface facing the first direction; and A sensor layer, opposite to the plurality of array electrodes, The plurality of array electrodes are arranged in each of a second direction intersecting the first direction and a third direction intersecting both the first direction and the second direction. The elastic deformation portion has a plurality of first protrusions arranged in the second direction and the third direction, The first protrusion is configured to overlap each of at least two or more array electrodes arranged in the second direction and at least two or more array electrodes arranged in the third direction when viewed from the first direction. The input portion has a plurality of second protrusions arranged in the second direction and the third direction, The second protrusion is arranged to overlap each of at least two or more first protrusions arranged in the second direction and at least two or more first protrusions arranged in the third direction when viewed from the first direction.

2. The load detection device according to claim 1, wherein: The second protrusion is arranged to overlap with each of at least three or more first protrusions arranged in the second direction and at least three or more first protrusions arranged in the third direction when viewed from the first direction. Among at least nine or more first protrusions overlapping one second protrusion when viewed from the first direction, ends of some of the first protrusions in the first direction are bonded to the second protrusion, and ends of the remaining first protrusions in the first direction are not bonded to the second protrusion.

3. The load detection device according to claim 1 or 2, wherein: The second protrusion has a higher rigidity than the first protrusion.

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