Load sensor device

Abstract

A load sensor device of one embodiment of the present invention comprises: a load sensor element having a pressure-receiving portion; a housing for accommodating the load sensor element; and a pressing component supported by the housing, the pressing component comprising: an elastic body for bearing a load; a rigid pressing portion in contact with the pressure-receiving portion; and an elastic supporting portion for supporting the rigid pressing portion on the housing, and a gap is provided between the rigid pressing portion and the pressure-receiving portion when no load is applied to the pressing component, thereby achieving high accuracy of the detection value and obtaining sufficient tolerance during assembly.

Description

Technical Field

[0001] The present invention relates to a load sensor device for sensing load. Background Art

[0002] In recent years, load sensor devices for sensing loads have become increasingly common in electronic devices and the like. Patent Document 1 discloses a force detection device comprising: a substrate having at least two force detection conductive pads and a common conductive pad disposed therebetween; an elastic plate made of conductive rubber or conductive elastomer, disposed opposite the force detection conductive pads and the common conductive pad; a contact resistance generating surface having numerous microprotrusions formed on the surface of the elastic plate facing the force detection conductive pads; and flat conductive elastic contacts formed on the surface of the elastic plate facing the common conductive pads.

[0003] Patent document 2 discloses the following touch screen input operation device, which comprises: a touch screen component made of a transparent material, having an operation surface for contact by a detected object for performing input operation, and provided with a touch sensor portion for sensing the position where the detected object has contacted the operation surface and outputting a signal; an upper bracket, which holds the upper side of the touch screen component and has an opening for opening the operation surface; a lower bracket made of a conductive component, which is arranged behind the touch screen component and holds the lower side of the touch screen component; a box body, which is arranged behind the lower bracket; a light source, which guides light into the lower bracket made of a light-guiding component; a push switch, which is arranged between the lower bracket and the box body, follows the pressing action of the operation surface of the touch screen component and outputs a push signal to determine the input of the touch sensor portion; and a circuit substrate, on which the push switch and the light source are mounted.

[0004] Patent document 3 discloses the following pressure-sensitive device, which comprises: a pressure sensor having a pressure-sensitive surface; a membrane component having elasticity and being fixed around the pressure-sensitive surface in a manner opposed to the pressure-sensitive surface with a gap therebetween; and an elastic component located between the pressure-sensitive surface and the membrane component, which transmits the force applied to the membrane component to the pressure-sensitive surface.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2002-124404

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 2014-142777

[0009] Patent Document 3 International Publication No. WO2019 / 167688 Summary of the Invention

[0010] Problems to be solved by the invention

[0011] Load sensor devices that sense loads require not only high sensing accuracy and linearity of the detected load values, but also tolerances required when assembling the load sensor element within a housing. For example, if the load-bearing component must be brought into contact with the load sensor element beforehand during assembly, accurate alignment of the load-bearing component and the load sensor element is essential, making assembly difficult.

[0012] The present invention has been made in view of such actual circumstances, and an object of the present invention is to provide a load sensor device that can achieve high accuracy of detection values ​​and obtain a sufficient tolerance during assembly.

[0013] Solutions for solving problems

[0014] One embodiment of the present invention is a load sensor device comprising: a load sensor element having a pressure-receiving portion; a housing for accommodating the load sensor element; and a pressing component supported by the housing, the pressing component comprising: an elastic body for bearing a load; a rigid pressing portion in contact with the pressure-receiving portion; and an elastic supporting portion for supporting the rigid pressing portion on the housing, wherein a gap is provided between the rigid pressing portion and the pressure-receiving portion when no load is applied to the pressing component.

[0015] With this configuration, by providing the pressing member with elasticity, when the elastic body is pressed, the load can be transferred from the elastic body to the pressure-receiving portion via the elastic support portion and the rigid pressing portion. In this case, the rigid pressing portion in contact with the pressure-receiving portion can be made of a highly rigid material, for example. This can suppress load loss and improve sensitivity. Furthermore, a gap exists between the rigid pressing portion and the pressure-receiving portion, thereby allowing for tolerance in assembly.

[0016] In the load sensor device, the elastic support portion may include a leaf spring portion. The elastic support portion may be in the shape of a leaf spring, thereby facilitating the transmission of the load to the pressure receiving portion.

[0017] In the load sensor device described above, the elastic support portion may be a part of the elastic body, thereby simplifying the device configuration.

[0018] In the load sensor device, a rigid plate portion may be provided between the elastic body and the rigid pressing portion. Providing such a rigid plate portion can suppress loss of load transmitted from the elastic body to the rigid pressing portion, thereby improving measurement accuracy.

[0019] In the load sensor device, the load sensor element preferably includes a displacement portion that is displaced by a load applied to a pressure-receiving portion, and a plurality of piezoresistive elements that electrically detect the displacement of the displacement portion. Using such a load sensor element with a plurality of piezoresistive elements can improve the linearity of load measurement.

[0020] In the load sensor device, the rigid pressing portion may be made of metal or silicon, thereby improving the durability of the contact between the rigid pressing portion and the pressure receiving portion of the load sensor element.

[0021] In the load sensor device, the elastic body may be made of metal, thereby enabling efficient transmission of the load from the metal elastic body to the rigid pressing portion.

[0022] In the above-mentioned load sensor device, the elastic body may include: a first contact portion including a first contact point that bears the load; a second contact portion including a second contact point that contacts the rigid pressing portion; and a vertical piece portion provided between the first contact portion and the second contact portion, for providing a space between the first contact portion and the second contact portion, and when a load is applied to the pressing component, the second contact portion is elastically deformed toward the space side due to the resistance from the rigid pressing portion. Thus, the elastic deformation of the second contact portion can absorb the resistance from the rigid pressing portion when the load is applied to the pressing component, and the load can be efficiently transferred to the pressurized portion. In this case, based on the viewpoint of efficiently transferring the pressing force received from the first contact point to the rigid pressing portion, it is preferred to have a structure in which the elastic deformation of the second contact portion takes precedence over the elastic deformation of the vertical piece portion.

[0023] In the load sensor device described above, the first contact portion, the second contact portion, and the vertical piece are preferably integrated using a metal plate. This allows the elastic body to be formed from a single metal plate. In this case, from the perspective of efficiently transmitting the pressing force exerted on the first contact point to the rigid pressing portion, when the second contact portion is formed from the two ends of the metal plate, the two ends are preferably joined and integrated to form the second contact portion.

[0024] The load sensor device may further include an integrated circuit housed in the housing and carrying the load sensor element, thereby enabling the function of the integrated circuit to be embedded in the load sensor device.

[0025] In the load sensor device, the housing may be provided with a restriction portion that restricts movement of the rigid pressing portion in a direction perpendicular to the pressing direction. This can suppress friction between the rigid pressing portion and the pressure receiving portion.

[0026] The load sensor device may further include a cover disposed on the opposite side of the pressing member from the housing to apply a load to the elastic body. This allows the load received by the cover to be transmitted from the pressing member to the load sensor element via the rigid pressing portion.

[0027] In the load sensor device, the cover may be provided with a convex portion that contacts the elastic body, thereby enabling efficient transmission of the load from the convex portion of the cover to the elastic body.

[0028] In the load sensor device, the elastic body and the convex portion may be formed integrally or connected to the convex portion, thereby enabling the load to be transmitted from the convex portion of the cover to the elastic body without loss.

[0029] The load sensor device may further include a stopper for limiting the relative distance between the cover and the housing. The stopper limits the cover and the housing from approaching each other beyond necessity, thereby preventing overload on the load sensor element.

[0030] Effects of the Invention

[0031] According to the present invention, it is possible to provide a load sensor device that can achieve high accuracy of detection values ​​and obtain a sufficient tolerance during assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1A It is a perspective view showing an example of the configuration of the load sensor device according to this embodiment.

[0033] Figure 1B This is a cross-sectional view illustrating the configuration of the load sensor device according to this embodiment.

[0034] Figure 2 This is an exploded perspective view of the load sensor device according to this embodiment.

[0035] Figure 3 The figure is a top view showing an example of the displacement portion of the load sensor element.

[0036] Figure 4A This is a diagram illustrating the operation of the load sensor device according to this embodiment.

[0037] Figure 4B This is a diagram illustrating the operation of the load sensor device according to this embodiment.

[0038] Figure 5A Graph showing stress distribution when a load is applied to the load sensor device of this embodiment.

[0039] Figure 5B Graph showing stress distribution when a load is applied to the load sensor device of this embodiment.

[0040] Figure 5C Graph showing stress distribution when a load is applied to the load sensor device of this embodiment.

[0041] Figure 6A A diagram showing a pressing state when a rigid pressing portion is used.

[0042] Figure 6B A diagram showing a pressing state when a rigid pressing portion is used.

[0043] Figure 7A A diagram showing a pressing state when an elastic pressing portion is used.

[0044] Figure 7B A diagram showing a pressing state when an elastic pressing portion is used.

[0045] Figure 8A This is an enlarged view of the stress distribution of the pressure-receiving part and the pressing part.

[0046] Figure 8B This is an enlarged view of the stress distribution of the pressure-receiving part and the pressing part.

[0047] Figure 9 This is a diagram showing the stress of the displacement portion relative to the load.

[0048] Figure 10 Graph showing linearity error of output values ​​of a load sensor element with respect to load.

[0049] Figure 11 It is a cross-sectional view showing another example of the load sensor device according to the present embodiment.

[0050] Figure 12 It is an exploded perspective view showing another example of the load sensor device according to the present embodiment.

[0051] Figure 13A This is a diagram showing the output characteristics of the load sensor device.

[0052] Figure 13B This is a diagram showing the output characteristics of the load sensor device.

[0053] Figure 14A It is a plan view showing another example (one) of the elastic support portion.

[0054] Figure 14B It is a plan view showing another example (part 2) of the elastic support portion.

[0055] Figure 14C It is a plan view showing another example (part 3) of the elastic support portion.

[0056] Figure 15A It is a perspective view showing another example (fourth) of the elastic support portion.

[0057] Figure 15B It is a perspective view showing another example (fifth) of the elastic support portion.

[0058] Figure 16A It is a perspective view showing another example (No. 6) of the elastic support portion.

[0059] Figure 16B It is a perspective view showing another example (No. 7) of the elastic support portion.

[0060] Figure 17 This is a perspective view showing another example (one) of the elastic body.

[0061] Figure 18A It is a perspective view showing another example (Part 2) of the elastic body.

[0062] Figure 18B It is a cross-sectional view showing another example (part 2) of the elastic body.

[0063] Figure 19 This is a perspective view showing another example (part 3) of the elastic body.

[0064] Figure 20 This is a perspective view showing another example (fourth) of a load sensor device using an elastic body.

[0065] Figure 21 This is an exploded perspective view showing another example (fourth) of a load sensor device using an elastic body.

[0066] Figure 22 This is a cross-sectional view illustrating another example (fourth) of a load sensor device using an elastic body.

[0067] Figure 23 It is a cross-sectional view showing another example (fourth) of the elastic body.

[0068] Figure 24A This is a cross-sectional view illustrating the operation of another example (fourth example) of a load sensor device using an elastic body.

[0069] Figure 24B This is a cross-sectional view illustrating the operation of another example (fourth example) of a load sensor device using an elastic body.

[0070] Figure 25A This is a cross-sectional view illustrating the operation of a load sensor device using an elastic body according to a comparative example.

[0071] Figure 25BThis is a cross-sectional view illustrating the operation of a load sensor device using an elastic body according to a comparative example.

[0072] Figure 26A A cross-sectional view of a load sensor device including an integrated circuit is shown as an example.

[0073] Figure 26B A cross-sectional view of a load sensor device including an integrated circuit is shown as an example.

[0074] Figure 27 It is a perspective view showing an example of a load sensor device including a cover.

[0075] Figure 28 This is an exploded perspective view showing an example of a load sensor device including a cover.

[0076] Figure 29 It is a cross-sectional view showing an example of a load sensor device including a cover portion.

[0077] Figure 30 It is an enlarged cross-sectional view showing an example of a load sensor device including a cover portion. DETAILED DESCRIPTION

[0078] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same reference numerals are given to the same components, and description of components previously described will be omitted as appropriate.

[0079] (Configuration of Load Sensor Device)

[0080] Figure 1A as well as Figure 1B This is a diagram illustrating the configuration of the load sensor device according to this embodiment. Figure 1A A perspective view of the load sensor device is shown in FIG. Figure 1B A cross-sectional view of the load sensor device is shown in FIG.

[0081] Figure 2 This is an exploded perspective view of the load sensor device according to this embodiment.

[0082] Figure 3 The figure is a top view showing an example of the displacement portion of the load sensor element.

[0083] The load sensor device 1 of this embodiment is a device that receives an external load and outputs a signal corresponding to the load. The load sensor device 1 includes a load sensor element 10, a housing 20 that houses the load sensor element 10, and a pressing member 30 supported by the housing 20. In the description of the embodiment, the normal direction of the surface of the housing 20 on which the load sensor element 10 is mounted is referred to as the Z direction, one of the directions orthogonal to the normal direction (the Z direction) is referred to as the X direction, and the other direction is referred to as the Y direction.

[0084] The load sensor element 10 includes a pressure-receiving portion 11 and a sensor substrate 12. The pressure-receiving portion 11 protrudes from the upper surface of the sensor substrate 12, for example, in a cylindrical shape, and receives external load. The pressure-receiving portion 11 is made of a silicon compound or silicon (the same material as the sensor substrate 12).

[0085] The sensor substrate 12 includes a displacement portion 121 that is displaced by the load applied to the pressure-receiving portion 11, and a plurality of piezoresistive elements 122 that electrically detect the displacement of the displacement portion 121. The sensor substrate 12 is bonded to the base substrate 13 and connected to the housing 20 via the base substrate 13. The displacement portion 121 is displaced by the load applied to the pressure-receiving portion 11 and is located on the surface of the sensor substrate 12 opposite the pressure-receiving portion 11.

[0086] The piezoresistive element 122 electrically detects the displacement of the displacement portion 121. Multiple piezoresistive elements 122 are provided in the displacement portion 121. These piezoresistive elements 122 are arranged along the periphery of the displacement portion 121, with adjacent elements 90° out of phase (orthogonal to each other). When the displacement portion 121 is displaced by the load borne by the pressure-receiving portion 11, the resistance of the piezoresistive elements 122 changes in accordance with the displacement, causing the midpoint potential of the bridge circuit formed by these piezoresistive elements 122 to change, and this midpoint potential becomes the sensor output.

[0087] The housing 20 is formed in a box shape, for example, and has a rim 21 and a central recessed housing portion 22. The rim 21 forms the uppermost surface of the housing 20 and functions as a stopper when receiving external load.

[0088] The load sensor 10 is housed in the housing portion 22. The housing portion 22 is provided with pads, and the housed load sensor 10 and the pads are electrically connected via bonding wires 15. A resin (not shown) may be embedded in the housing portion 22 to protect the bonding wires 15 and the like.

[0089] A step portion 23 is provided inside the edge portion 21 so as to surround the housing portion 22. On the step portion 23, a buffer portion 50 and a rigid pressing portion 32 of the pressing member 30, which will be described later, are placed.

[0090] The pressing member 30 includes an elastic body 31 that bears external loads; a rigid pressing portion 32 that contacts the pressure-receiving portion 11; and an elastic support portion 33 that supports the rigid pressing portion 32 against the housing 20. The elastic body 31 includes a protrusion 311 and a flange 312. The elastic body 31 is formed of, for example, rubber. The protrusion 311 is, for example, cylindrical, and the flange 312 has a surface for placing the protrusion 311 on the rigid pressing portion 32.

[0091] The rigid pressing portion 32 is a plate-shaped member formed from a material harder than the elastic body 31. For example, a stainless steel plate approximately 0.2 mm thick is used for the rigid pressing portion 32. Silicon, ceramic, glass, aluminum, or the like can be used as the rigid pressing portion 32. The elastic modulus of the rigid pressing portion 32 is higher than that of the elastic body 31, preferably being 60 GPa or greater.

[0092] The elastic support portion 33 includes a frame portion 331 placed on the step portion 23 of the housing 20 and an arm portion 332 connecting the frame portion 331 to the rigid pressing portion 32. The elastic support portion 33 supports the rigid pressing portion 32, so that the rigid pressing portion 32 is positioned above the housing portion 22 with the elastic support portion 33 interposed therebetween.

[0093] The arm portion 332 is a leaf spring portion that functions as a leaf spring. The rigid pressing portion 32 is supported at a predetermined spring constant by the elastic deformation of the arm portion 332. This spring constant is adjusted not only by the material of the arm portion 332 but also by its width, thickness, length, and shape. The arm portion 332 is symmetrically centered around the rigid pressing portion 32 in a leaf spring shape, thereby facilitating the transfer of the load from the elastic body 31 to the pressure-receiving portion 11 directly below.

[0094] Furthermore, by providing elasticity to the pressing member 30, when the elastic body 31 is pressed, a load can be transmitted from the elastic body 31 to the pressure-receiving portion 11 of the load sensor 10 via the elastic support portion 33 and the rigid pressing portion 32. In this case, the rigid pressing portion 32 in contact with the pressure-receiving portion 11 can be formed of a highly rigid material (such as metal or silicon), thereby suppressing load loss and improving detection sensitivity.

[0095] When a load sensor 10 uses a bridge circuit composed of multiple piezoresistive elements 122 to obtain an output, the convex pressure-receiving portion 11 must bear the load in order to efficiently displace the displaceable portion 121. Therefore, when the load is transferred from the pressing member 30 to the pressure-receiving portion 11, if the rigidity of the components in contact with the pressure-receiving portion 11 is low, the load cannot be effectively transferred to the pressure-receiving portion 11. In this embodiment, since the rigid pressing member 32 presses the pressure-receiving portion 11, the loss of external load can be suppressed, allowing for efficient load transfer to the pressure-receiving portion 11.

[0096] (Assembly of the load cell device)

[0097] In the above configuration, the load sensor 10 is housed in the housing portion 22 of the housing 20, and the load sensor 10 is connected to the pads of the housing portion 22 via bonding wires 15. Furthermore, the elastic support portion 33 of the pressing member 30 is placed on the step portion 23 of the housing portion 22, and the elastic body 31 is placed on the rigid pressing portion 32.

[0098] Then, in this state, the frame 40 is placed over the housing 20. The frame 40 is secured by hooking onto the hook 25 provided on the side of the housing 20. A hole 40h is provided in the center of the frame 40. When the frame 40 is placed over the housing 20, the protrusion 311 protrudes upward from the hole 40h. The elastic body 31 is pressed against the frame 40 at the flange 312. This secures the pressing member 30 to the housing 20.

[0099] In the load sensor device 1 assembled in this manner, a gap d is provided between the rigid pressing portion 32 and the pressure receiving portion 11 when no load is applied to the pressing member 30. In other words, the surface of the rigid pressing portion 32 on the pressure receiving portion 11 side does not contact the pressure receiving portion 11. The presence of gap d between the rigid pressing portion 32 and the pressure receiving portion 11 allows for adjustment of assembly tolerances.

[0100] That is, if the rigid pressing portion 32 comes into contact with the pressure receiving portion 11 or comes close to contact, the two may collide due to dimensional errors, misalignment during assembly, etc. If a highly rigid component such as the rigid pressing portion 32 collides with the pressure receiving portion 11, it may adversely affect the load sensor 10. By providing a gap d between the rigid pressing portion 32 and the pressure receiving portion 11, as in this embodiment, collisions during assembly can be actively avoided, thereby protecting the load sensor 10.

[0101] (Operation of the load cell device)

[0102] Figure 4A as well as Figure 4B This is a diagram illustrating the operation of the load sensor device according to this embodiment. Figure 4A: is a diagram showing an example of a state where a load is applied to the load sensor device 1. Figure 4B An example of the load cell output is shown in . Figure 4B The horizontal axis represents the stroke of the plate 50 in the Z direction, and the vertical axis represents the output value (relative value).

[0103] like Figure 4A As shown, a load is applied to the elastic body 31 of the pressing member 30 of the load sensor device 1 via the plate 50. When a load is applied to the elastic body 31 in the Z direction from the plate 50, the rigid pressing portion 32 supported by the spring action of the elastic supporting portion 33 is pressed in the Z direction.

[0104] Here, since a gap d is provided between the rigid pressing portion 32 and the pressure receiving portion 11 of the load sensor 10 , no load is applied to the pressure receiving portion 11 until the rigid pressing portion 32 and the pressure receiving portion 11 come into contact.

[0105] therefore, Figure 4B As shown, no output is generated from the time a load is applied to the load sensor device 1 until a predetermined stroke S1 is reached. This region is referred to as the pre-stroke region R1. In the pre-stroke region R1, when a load is applied, the elastic support portion 33 elastically deforms. While the pressing member 30 travels until the rigid pressing portion 32 contacts the pressure receiving portion 11, the load is not transmitted to the pressure receiving portion 11, and the output value does not increase. The length of the pre-stroke region R1 can be set based on the gap d.

[0106] Next, if a load is applied beyond the pre-stroke region R1, the output value increases in accordance with the stroke. This region is referred to as the force-bearing region R2. Since the rigid pressing portion 32 is in contact with the pressure-receiving portion 11 in the force-bearing region R2, the load is transmitted from the elastic body 31 to the pressure-receiving portion 11 via the rigid pressing portion 32. Due to the rigidity of the rigid pressing portion 32 in contact with the pressure-receiving portion 11, the output value from the load sensor 10 increases in a manner roughly proportional to the magnitude of the stroke (load). The output value increases in accordance with the stroke to V1.

[0107] The force-bearing region R2 continues until the edge 21 of the housing 20 functions as a stopper. Specifically, the pressing member 30 is pressed inward, and if the plate 50 contacts the edge 21 of the housing 20, it is not pushed in further. As a result, the stroke of the pressing member 30 reaches S2, and the output value does not increase further, preventing overload on the load sensor 10.

[0108] Figures 5A to 5C Graph showing stress distribution when a load is applied to the load sensor device of this embodiment. Figure 5A Indicates the state where no load is applied ( Figure 4BIn this state, the arm portion 332 of the elastic support portion 33 supporting the rigid pressing portion 32 between the elastic body 31 and the pressure receiving portion 11 is not deformed. Therefore, when viewed from the side, the rigid pressing portion 32 is blocked by the frame portion 331.

[0109] Figure 5B In FIG. 1 , the pressing member 30 is pressed in the Z direction by the application of the load, so that the rigid pressing portion 32 is in contact with the pressure receiving portion 11 ( Figure 4B The stress distribution in the state of stroke S1 is shown. The load from the plate 50 is transmitted to the rigid pressing portion 32 via the elastic body 31. As a result, the rigid pressing portion 32 moves toward the pressure receiving portion 11 in the Z direction while being supported by the arm portion 332 of the elastic support portion 33, thereby contacting the pressure receiving portion 11.

[0110] Figure 5C The plate 50 is in contact with the edge 21 of the housing 20 ( Figure 4B As shown in the stress distribution in the state of the stroke S2, it can be understood that the load applied from the plate 50 is effectively transmitted from the rigid pressing portion 32 to the load sensor element 10 via the pressure receiving portion 11.

[0111] Furthermore, even if the plate 50 approaches the load sensor device 1 at an angle (contact at one end) for some reason (e.g., due to uneven assembly), the elastic member 31, which is in direct contact with the plate 50, deforms, thereby stabilizing the contact between the plate 50 and the elastic member 31. Furthermore, the elastic member 31, bearing the load, deforms the arm portion 332 while simultaneously displacing the rigid pressing portion 32 in the Z direction toward the pressure receiving portion 11. In this manner, the elastic member 31 stabilizes the contact between the pressing member 30 and the plate 50, while the rigid pressing portion 32 optimizes the contact between the pressing member 30 and the load sensor element 10.

[0112] (Example)

[0113] Next, a comparison of the hardness of the pressing portion in contact with the pressure receiving portion 11 will be described.

[0114] Figure 6A as well as Figure 6B This is a diagram showing a pressing state when the rigid pressing portion 32 is in contact with the pressure receiving portion 11 as an example of the present invention. Figure 6A : is a schematic cross-sectional view showing a state in which the rigid pressing portion 32 is in contact with the pressure receiving portion 11, Figure 6B 3 shows a stress distribution diagram when a load is applied to the pressure receiving portion 11 from the rigid pressing portion 32 .

[0115] Figure 7A as well as Figure 7BThis figure shows a pressing state when an elastic pressing portion 32B having a low elastic modulus, instead of the rigid pressing portion 32 , contacts the pressure receiving portion 11 as a comparative example. Figure 7A : is a schematic cross-sectional view showing a state in which the elastic pressing portion 32B is in contact with the pressure receiving portion 11, Figure 7B 3 shows a stress distribution diagram when a load is applied to the pressure receiving portion 11 from the elastic pressing portion 32B.

[0116] Figure 8A as well as Figure 8B This is an enlarged view of the stress distribution in the pressure-receiving part and the pressing part. Figure 8A Shown in Figure 6B The stress distribution at the contact portion between the rigid pressing portion 32 and the pressure receiving portion 11 is shown in FIG. Figure 8B Shown in Figure 7B FIG. 1 is an enlarged view of the stress distribution at the contact portion between the elastic pressing portion 32B and the pressure receiving portion 11 .

[0117] Stainless steel (SUS304) is used for Figure 6 and Figure 8A The rigid pressing portion 32 shown in FIG. 7 and FIG. 8 is made of rubber (hardness 70 (measured using a Durometer Type A)). Figure 8B The load on the pressure receiving portion 11 of the elastic pressing portion 32B shown is 6N.

[0118] When using a rigid pressing portion 32, the load is concentratedly transferred toward the sensor substrate, centered around the contact point with the pressure-receiving portion 11. On the other hand, when using an elastic pressing portion 32B, the pressure-receiving portion 11 bites into the elastic pressing portion 32B, distributing the load. Therefore, the rigid pressing portion 32 only needs to have enough rigidity so that the contact surface with the pressure-receiving portion 11 is within the pressure-receiving surface of the pressure-receiving portion 11. The area of ​​this contact surface can be calculated using Hertz's contact theory.

[0119] Figure 9 This is a diagram showing the stress of the displacement portion with respect to the load.

[0120] When the elastic pressing portion 32B is used, the load is dispersed, and thus the load cannot be efficiently transmitted from the pressure receiving portion 11 to the sensor substrate 12. As a result, the stress transmitted to the displacement portion 121 of the sensor substrate 12 relative to the load does not increase. On the other hand, when the rigid pressing portion 32 is used, the load can be efficiently transmitted to the sensor substrate, and the stress transmitted to the displacement portion 121 of the sensor substrate 12 relative to the load can be increased. Figure 9 The stress change of the displacement portion 121 with respect to the load is equivalent to the sensitivity. Therefore, compared with the elastic pressing portion 32B, the rigid pressing portion 32 can obtain more sufficient sensitivity.

[0121] Figure 10 Graph showing linearity error of output values ​​of a load sensor element with respect to load.

[0122] When using the elastic pressing portion 32B, the pressure-receiving portion 11 bites into the elastic pressing portion 32B by up to 4N, distributing the load and resulting in a large linear error. On the other hand, when using the rigid pressing portion 32, the pressure-receiving portion 11 does not bite into the rigid pressing portion 32, and load loss is almost nonexistent. Therefore, the linear error is significantly reduced.

[0123] (Other Examples of Load Sensor Devices)

[0124] Figure 11 It is a cross-sectional view showing another example of the load sensor device according to the present embodiment.

[0125] Figure 12 It is an exploded perspective view showing another example of the load sensor device according to the present embodiment.

[0126] like Figure 11 as well as Figure 12 As shown, a load sensor device 1B according to another example includes a rigid plate portion 60 between the elastic body 31 and the rigid pressing portion 32 .

[0127] In the load sensor device 1 described above, the rigid pressing portion 32 is directly pressed by the elastic body 31, but since a portion of the elastic body 31 (the flange portion 312) is in contact with the frame and the frame portion 331 of the elastic support portion 33, a portion of the load borne is dispersed, resulting in attenuation of the force transmitted to the load sensor element 10.

[0128] On the other hand, in the load sensor device 1B, the load borne by the elastic body 31 is transmitted to the rigid pressing portion 32 via the rigid plate portion 60. The rigid plate portion 60 can transmit the force to the central portion of the rigid pressing portion 32 without interfering with other components. Therefore, the load borne by the elastic body 31 is easily transmitted to the load sensor element 10, and sensitivity can be improved.

[0129] Figure 13A as well as Figure 13B This is a diagram showing the output characteristics of the load sensor device. Figure 13A as well as Figure 13B In each of the graphs, the horizontal axis represents the load, and the vertical axis represents the output value of the load sensor element 10 . Figure 13A The output characteristics of the load sensor device 1 are shown in FIG. Figure 13B The output characteristics of the load sensor device 1B are shown in . When the same load is applied, the load sensor device 1B obtains an output value approximately 1.6 times greater than that of the load sensor device 1 .

[0130] Even in the load sensor device 1B including the rigid plate portion 60, the pre-stroke region R1 is set by the gap d provided between the rigid pressing portion 32 and the pressure receiving portion 11 of the load sensor element 10, as in the load sensor device 1 (see Figure 4B In this case, the size of the pre-stroke region R1, which extends from the start of load application to the predetermined stroke S1, can be set by the thickness of the rigid plate portion 60. Specifically, the thinner the rigid plate portion 60, the larger the gap d, and the larger the pre-stroke region R1. On the other hand, the thicker the rigid plate portion 60, the smaller the gap d, and the smaller the pre-stroke region R1.

[0131] (Other Examples of Elastic Supporting Portions)

[0132] 14A to 14C It is a plan view showing another example of the elastic support portion.

[0133] Figure 14A , another example (one) of the elastic support portion 33 is shown. Figure 14B Another example (part 2) of the elastic support portion 33 is shown in FIG. Figure 14C 3 shows another example (part 3) of the elastic support portion 33 .

[0134] like 14A to 14C As shown in FIG. 3 , various shapes can be considered for the shape of the arm portion 332 of the elastic support portion 33. Figure 14A In the embodiment, the arm portion 332 is arranged to be line symmetrical with respect to the rigid pressing portion 32 arranged in the center. Figure 14B as well as Figure 14C In the embodiment, the arm portion 332 is arranged to be point symmetrical with respect to the rigid pressing portion 32 arranged in the center. Figure 14B In the embodiment, the arm portion 332 is configured to be bent. Figure 14C In FIG, the arm portion 332 is provided in a spiral shape.

[0135] The arm portion 332 has such a shape that the rigid pressing portion 32 is easy to elastically deform in the direction close to the pressure-receiving portion 11 (Z direction), but is not easy to elastically deform in other directions (for example, the in-plane direction of the frame portion 331: XY direction). That is, the arm portion 332 has anisotropy in the difficulty of elastic deformation. Therefore, the load applied to the plate 50 is efficiently transferred to the pressure-receiving portion 11. In addition, even if there is unevenness in the direction of the load applied to the plate 50, the elastic body 31 can appropriately bear the load by elastically deforming, and the elastic body 31 can effectively transfer the borne load in the direction of the pressure-receiving portion 11 (Z direction) by having the arm portion 332 that is anisotropic in the difficulty of elastic deformation. In particular, by Figure 14A The shape of the elastic support portion 33 shown in the figure has an excellent anisotropic effect of elastic deformation, thereby improving the contact reliability with the pressure receiving portion 11. Figure 14B as well as Figure 14C In the shape of the elastic support portion 33 shown, the arm portion 332 is long and easily elastically deformed, thereby easily obtaining a soft pre-stroke feeling.

[0136] The spring structure of the elastic support portion 33 supports the centrally located rigid pressing portion 32 with a predetermined spring constant. In this spring structure, the longer or narrower the arm portion 332, the smaller the spring constant (making it easier to displace with a small load). Similarly, the thinner the arm portion 332, the smaller the spring constant. However, when stainless steel is used, a thickness of approximately 0.2 mm is preferred to ensure the strength of the rigid pressing portion 32.

[0137] Furthermore, if the in-plane displacement of the rigid pressing portion 32 supported by the arm portion 332 can be suppressed, the risk of wear caused by contact between the rigid pressing portion 32 and the pressure receiving portion 11 of the load sensor element 10 can be reduced, thereby providing a more reliable product.

[0138] Figure 15A It is a perspective view showing another example (fourth) of the elastic support portion.

[0139] Figure 15B It is a perspective view showing another example (fifth) of the elastic support portion.

[0140] Figure 16A It is a perspective view showing another example (No. 6) of the elastic support portion.

[0141] Figure 16B It is a perspective view showing another example (No. 7) of the elastic support portion.

[0142] In any of the above figures, for the convenience of explanation, the state in which the elastic body 31 is removed is shown.

[0143] In other examples (four) to (seven) of the elastic support portion 33, a positioning hole 331h is provided in the frame portion 331. A positioning protrusion 23a is provided on the step portion 23 of the housing 20 on which the frame portion 331 is placed. When the frame portion 331 is placed on the step portion 23, the protrusion 23a engages with the positioning hole 331h, thereby determining the placement position of the elastic support portion 33.

[0144] for Figures 15A to 16B In the elastic support portion 33 shown, the plate width (width in the Y direction) of the connecting portion 332a of each arm portion 332 and the rigid pressing portion 32 is different. Figure 15A The connecting portion 332a of the arm portion 332 of the elastic support portion 33 shown in FIG. 3 is the narrowest. Figure 15B 、 Figure 16A as well as Figure 16B The width of the connecting portion 332a of the arm 332 of the elastic support 33 decreases as the plate width decreases, making it easier to obtain a soft pre-stroke feel. On the other hand, the wider the plate width of the connecting portion 332a of the arm 332, the greater the spring constant, making it easier to obtain a pressing feel.

[0145] (Other examples of elastic bodies)

[0146] Figure 17 This is a perspective view showing another example (one) of the elastic body.

[0147] Figure 17 The elastic body 31B shown in the figure also serves as the elastic support portion 33. That is, the elastic support portion 33 becomes a part of the elastic body 31B. Specifically, the rigid pressing portion 32 is embedded in the surface of the elastic body 31B on the load sensor element 10 side, and the flange portion 312 of the elastic body 31 also serves as the elastic support portion 33 that supports the rigid pressing portion 32. When using such an elastic body 31B, it is not necessary to Figure 2 The plate-shaped elastic support portion 33 shown can simplify the structure of the pressing member 30 .

[0148] Figure 18A FIG2 is a perspective view showing another example (part 2) of an elastic body. Figure 18A 4 shows a state where the frame 40 is removed. Figure 18B It is a cross-sectional view showing another example (part 2) of the elastic body.

[0149] In another example (the second) of the elastomer 31, the flange portion 312 of the elastomer 31 extends to the edge 21 of the shell 20 in the X direction. A platform 21a is provided on the edge 21 of the shell 20, and the flange portion 312 of the elastomer 31 is placed on the platform 21a of the edge 21. A recess 31b is provided on the side surface 31a of the elastomer 31 opposite to the edge 21, and the recess 31b engages with the protrusion 20a provided on the shell 20, thereby positioning the elastomer 31. In addition, by covering the frame 40 from above the shell 20, the elastomer 31 is sandwiched between the frame 40 and the shell 20. If the elastomer 31 is provided with a flange portion 312, the flange portion 312 is sandwiched between the frame 40 and the shell 20, which can effectively prevent the elastomer 31 from deviating when lateral pressure is applied to the elastomer 31.

[0150] Figure 19 This is a perspective view showing another example (part 3) of the elastic body.

[0151] In another example (the third) of the elastic body 31, the flange portion 312 of the elastic body 31 extends to the edge 21 of the housing 20 in the X direction, and the flange portion 312 is placed on the platform 21a of the edge 21. In another example (the third) of the elastic body 31, no recess 31b is provided, but the elastic body 31 is positioned by the contact between the side surface 31a of the elastic body 31 and the inner peripheral surface of the housing 20, and the engagement between the inward-facing protrusions 21b provided at the four corners of the edge 21 and the notch 312b of the flange portion 312. In another example (the third) of the elastic body 31, the elastic body 31 is also sandwiched between the frame 40 and the housing 20 by covering the frame 40 from above. If the flange portion 312 is provided on the elastic body 31, the flange portion 312 is sandwiched between the frame 40 and the housing 20, which can effectively prevent the elastic body 31 from deviating when lateral pressure is applied to the elastic body 31.

[0152] Figure 20 This is a perspective view showing another example (fourth) of a load sensor device using an elastic body.

[0153] Figure 21 This is an exploded perspective view showing another example (fourth) of a load sensor device using an elastic body.

[0154] Figure 22 This is a cross-sectional view showing another example of a load sensor device (part 4) using an elastic body.

[0155] Figure 23 It is a cross-sectional view showing another example (fourth) of the elastic body.

[0156] The elastic body 31C of another example (fourth) is formed of metal. For example, the elastic body 31 is formed by bending a plate-shaped metal.

[0157] The elastic body 31C has: a first contact portion 3101, including a first contact point CP1 that bears the load; a second contact portion 3102, including a second contact point CP2 that contacts the rigid pressing portion 32; and a vertical piece portion 3103, arranged between the first contact portion 3101 and the second contact portion 3102, for setting a space S between the first contact portion 3101 and the second contact portion 3102.

[0158] In this elastic body 31C, a convex shape is formed by the first contact portion 3101 and the upright piece 3103. This convex shape is formed as the protrusion 311. The second contact portion 3102 is the portion opposite the first contact portion 3101, and a gap is provided between the second contact portion 3101 and the first contact portion 3101 according to the height of the upright piece 3103. This gap forms a space S between the first contact portion 3101 and the second contact portion 3102.

[0159] The elastic body 31C is formed integrally from a single metal sheet by, for example, bending the sheet. The two ends of the metal sheet are joined (welded, etc.) to form the elastic body 31C having an annular portion. The inner portion of the annular portion defines a space S.

[0160] Specifically, a first contact portion 3101 including a first contact point CP1 and extending in the horizontal direction (along the XY plane) is formed from a metal plate. The plate at each end of the first contact portion 3101 is bent downward at approximately right angles to form two vertical tabs 3103. Furthermore, the plate is bent from the vertical tabs 3103 toward the side opposite to the first contact portion 3101 in the horizontal direction and then folded back 180 degrees at a predetermined position to form the second contact portion 3102.

[0161] The two ends of the metal plate of the second contact portion 3102 can be joined in an overlapping state or in a state where the end faces are butted. In addition, from the perspective of joint strength, it is preferable to join in an overlapping state. In addition, the overlapping portion functions as the rigid plate portion 60, thereby achieving improved sensitivity. In addition, the metal plate from the vertical sheet portion 3103 to the second contact portion 3102 is bent in a state extending laterally, thereby forming the flange portion 312 of the elastic body 31C.

[0162] Figure 24A as well as Figure 24B This is a cross-sectional view illustrating the operation of another example (fourth example) of a load sensor device using an elastic body.

[0163] Figure 25A as well as Figure 25B This is a cross-sectional view illustrating the operation of a load sensor device using an elastic body according to a comparative example.

[0164] exist Figure 24A FIG. 3 shows a state before a load is applied to the load sensor device 1 using the elastic body 31C. Figure 24B 3 shows a state where a load is applied to the load sensor device 1 using the elastic body 31C. When the plate 50 is brought into contact with the elastic body 31C to apply the load, the load received by the first contact point CP1 of the first contact portion 3101 is applied to the rigid pressing portion 32 contacted by the second contact point CP2 of the second contact portion 3102.

[0165] The load applied to the rigid pressing portion 32 causes the elastic support portion 33 to bend, and the rigid pressing portion 32 approaches and eventually contacts the pressure-receiving portion 11 of the load sensor element 10. When the rigid pressing portion 32 contacts the pressure-receiving portion 11, the resistance force from the rigid pressing portion 32 causes the second contact portion 3102 to elastically deform toward the space S. The load from the plate 50 is transmitted to the rigid pressing portion 32 via the elastic body 31C, and then from the rigid pressing portion 32 to the load sensor element 10 via the pressure-receiving portion 11.

[0166] exist Figure 25A FIG shows a state before a load is applied to the load sensor device 1 using the elastic body 31D of the comparative example. Figure 25B 3 shows a state where a load is applied to the load sensor device 1 using the elastic body 31D of the comparative example. The elastic body 31D of the comparative example is formed by bending a metal plate in the same manner as the elastic body 31C, but the end of the second contact portion 3102 (the end of the metal plate) is not joined.

[0167] When the plate 50 is brought into contact with the elastic body 31D and a load is applied, the load borne by the first contact portion 3101 is applied to the rigid pressing portion 32 in contact with the second contact portion 3102. The load applied to the rigid pressing portion 32 causes the elastic support portion 33 to bend, and the rigid pressing portion 32 approaches and eventually contacts the pressure receiving portion 11 of the load sensor element 10. When the rigid pressing portion 32 contacts the pressure receiving portion 11, the resistance force from the rigid pressing portion 32 causes the second contact portion 3102 to elastically deform toward the space S.

[0168] At this point, the ends of the second contact portions 3102 are not joined. Therefore, as the load increases, the two second contact portions 3102 move in a wider direction. Furthermore, as the two second contact portions 3102 widen, the second contact portion 3102 side (lower side) of the vertical piece 3103 widens, causing the protrusion 311 to collapse. Thus, the protrusion 311 is more easily collapsed by the elastic body 31D than by the elastic body 31C.

[0169] In the simulation, when equal pressing forces were applied to the first contact portion 3101 of the elastic body 31C and the first contact portion 3101 of the elastic body 31D, the force transmitted to the rigid pressing portion 32 via the second contact portion 3102 of the elastic body 31D was 1 / 5 of the force transmitted to the rigid pressing portion 32 via the second contact portion 3102 of the elastic body 31C. As confirmed by this simulation, the load sensor device 1 using the elastic body 31C having a structure in which the elastic deformation of the second contact portion 3102 takes precedence over the elastic deformation of the upright piece 3103 can more efficiently transmit the load from the plate 50 to the load sensor element 10 than the load sensor device 1 using the elastic body 31D having a structure in which the elastic deformation of the upright piece 3103 takes precedence over the elastic deformation of the second contact portion 3102. The elastomer having a first contact portion 3101, a second contact portion 3102 and a vertical piece portion 3103 is formed by bending a metal plate. When the second contact portion 3102 is composed of two end portions of a metal plate, the two end portions of the metal plate are joined and integrated to form the second contact portion 3102, as in the elastomer 31C. In this way, the pressing force borne by the first contact portion 3101 can be efficiently transmitted to the rigid pressing portion 32.

[0170] (Example of a load sensor device including an integrated circuit)

[0171] Figure 26A as well as Figure 26B A cross-sectional view of a load sensor device including an integrated circuit is shown as an example.

[0172] The integrated circuit 70 used in the load sensor device 1C is, for example, an ASIC (Application Specific Integrated Circuit) that converts an analog signal output from the load sensor element 10 into a digital signal. The integrated circuit 70 may be a circuit other than a signal conversion circuit.

[0173] The integrated circuit 70 is mounted on the load sensor element 10. That is, the integrated circuit 70 and the load sensor element 10 are stacked in the housing portion 22 of the housing 20. Thus, a package structure including the integrated circuit 70 can be realized by a single load sensor device 1C.

[0174] exist Figure 26A , an example of using molded resin as the housing 20 of the load sensor device 1C is shown. Figure 26Bshows an example of using ceramic as the housing 20 of the load sensor device 1C. Using molded resin for the housing 20 allows for an inexpensive and lightweight load sensor device 1C. Furthermore, using ceramic for the housing 20 allows for a fine metallization pattern to be formed on the housing 20, enabling a more refined electrical connection with the integrated circuit 70.

[0175] (Example of a load sensor device equipped with a cover)

[0176] Figure 27 It is a perspective view showing an example of a load sensor device including a cover.

[0177] Figure 28 This is an exploded perspective view showing an example of a load sensor device including a cover.

[0178] Figure 29 It is a cross-sectional view showing an example of a load sensor device including a cover portion.

[0179] Figure 30 It is an enlarged cross-sectional view showing an example of a load sensor device including a cover portion.

[0180] The load sensor device 1D includes a cover portion 80 disposed on the side of the pressing member 30 opposite the housing 20. The housing 20 of the load sensor device 1D is provided with a restriction portion 27 that restricts the movement of the rigid pressing portion 32 in directions (X and Y directions) perpendicular to the pressing direction (Z direction). Specifically, the restriction portion 27 is a hole provided in the housing 20, which accommodates the load sensor element 10 and the pressing member 30 (elastic body 31, rigid pressing portion 32, and elastic support portion 33). Furthermore, the load sensor device 1D includes a rigid plate portion 60 between the elastic body 31 and the rigid pressing portion 32. The rigid plate portion 60 can be provided as needed.

[0181] The lengths of the hole of the restricting portion 27 in the X and Y directions are constant along the Z direction. The pressing member 30 can slide in the Z direction within the hole of the restricting portion 27 but is restricted from moving in the X and Y directions.

[0182] The cover 80 is provided with a convex portion 81 that contacts the elastic body 31. Therefore, if a load is applied from the cover 80, the load can be transferred from the convex portion 81 to the elastic body 31, and the load is transferred to the pressure-receiving portion 11 of the load sensor element 10 via the rigid pressing portion 32. At this time, the movement of the pressing component 30 in the X direction and the Y direction is restricted by the limiting portion 27 of the housing 20. Therefore, the movement of the rigid pressing portion 32 in the X direction and the Y direction is also restricted, and the friction between the rigid pressing portion 32 and the pressure-receiving portion 11 in the X direction and the Y direction is suppressed. Therefore, even if the pressure-receiving portion 11 is composed of a material with high hardness and low toughness such as silicon, damage to the pressure-receiving portion 11 caused by friction between the pressure-receiving portion 11 and the rigid pressing portion 32 can be suppressed.

[0183] The convex portion 81 of the cover 80 may be formed integrally with the elastic body 31 or may be connected to the elastic body 31. Thus, the load can be transmitted from the convex portion 81 of the cover 80 to the elastic body 31 without loss.

[0184] Furthermore, the load sensor device 1D preferably includes a stopper 85 to limit the relative distance between the cover 80 and the housing 20. For example, the stopper 85 may be formed by a protrusion provided near the convex portion 81 of the cover 80, at the portion facing the housing 20. When the cover 80 is pressed in, the stopper 85 abuts against the housing 20, preventing further insertion of the cover 80. This prevents overloading the load sensor element 10 even when an excessive load is applied to the cover 80. The stopper 85 is preferably located near the convex portion 81 of the cover 80. For example, if the rigidity of the cover 80 is low, it may be easily bent when the cover 80 is pressed in. If the stopper 85 is located near the convex portion 81, even if the cover 80 bends, the convex portion 81 can fully exert its stopping effect by pressing the load sensor element 10. Furthermore, the stopper 85 can be pre-positioned at a position away from the protrusion 81. This also achieves the effect of suppressing the deflection of the cover 80. Furthermore, the stopper 85 can be provided on the cover 80 side or on the housing 20 side. Specifically, the stopper 85 only needs to be provided at a position where the cover 80 and the housing 20 face each other, and can be provided on both the cover 80 and the housing 20.

[0185] The load sensor device 1D includes a cover 80, and therefore, the load sensor device 1D can be directly used as a component in a product that is arranged at a position that can be visually identified by the user. As a specific example of such a component, a panel switch arranged indoors or in a vehicle can be cited. An image display device can be provided on the side of the cover 80 for visual identification by the user. The pressing feeling of the cover 80 (the pressing response of the panel switch) can be changed by adjusting the material (elastic modulus) of the elastomer 31. In addition, the surface position of the cover 80 (the touch position of the panel switch) can be adjusted by adjusting the thickness of the elastomer 31.

[0186] As described above, according to the present embodiment, it is possible to provide the load sensor devices 1 , 1B, 1C, and 1D that can achieve high sensing accuracy and linearity of the detection value for the load and can also achieve a sufficient tolerance during assembly.

[0187] While the present embodiment has been described above, the present invention is not limited to these examples. For example, the shape of the arm portion 332 of the elastic support portion 33 is not limited to the shape described above. Furthermore, features obtained by adding, deleting, or modifying the design of the above-described embodiments as appropriate by those skilled in the art, as well as features obtained by appropriately combining features from the exemplary embodiments, are all within the scope of the present invention, as long as the gist of the present invention is retained.

[0188] Description of Reference Numerals

[0189] 1, 1B, 1C, 1D... Load sensor device

[0190] 10...Load sensor element

[0191] 11...pressure part

[0192] 12...Sensor substrate

[0193] 13……Base substrate

[0194] 15...bonding wire

[0195] 20... Shell

[0196] 20a…convex part

[0197] 21...Embo

[0198] 21a……Taibu

[0199] 21b…convex part

[0200] 22... Storage

[0201] 23...Steps

[0202] 23a……Protrusion

[0203] 25...Hook

[0204] 27...Restriction Department

[0205] 30... Pressing parts

[0206] 31, 31B, 31C, 31D... elastomer

[0207] 31a...side

[0208] 31b......concave part

[0209] 32... Rigid pressing part

[0210] 32B... elastic pressing part

[0211] 33... elastic support part

[0212] 40...frame

[0213] 40h...hole

[0214] 50...board

[0215] 60... Rigid plate

[0216] 70...Integrated Circuits

[0217] 80...Gaibu

[0218] 81…convex part

[0219] 85... Stop

[0220] 121...Displacement

[0221] 122...piezoresistive element

[0222] 311...The Bulge

[0223] 312...flange

[0224] 312b...notch

[0225] 331...frame

[0226] 331h...hole for positioning

[0227] 332...arm

[0228] 332a...Connection

[0229] 3101……First contact part

[0230] 3102...Second contact

[0231] 3103... Film Department

[0232] CP1…First point of contact

[0233] CP2...Second contact point

[0234] R1...Pre-travel area

[0235] R2……Force area

[0236] d...gap

[0237] S...Space

Claims

1. A load sensor device comprising: a load sensor element having a pressure-receiving portion; a housing for housing the load sensor element; and The pressing member is supported by the housing. The pressing component has: Elastomer, bearing load; a rigid pressing portion in contact with the pressed portion; and The elastic support portion supports the rigid pressing portion on the housing. When no load is applied to the pressing member, a gap is provided between the rigid pressing portion and the pressure receiving portion. The rigid pressing portion is formed of a material harder than the elastic body.

2. The load sensor device according to claim 1, wherein The elastic support portion includes a leaf spring portion.

3. The load sensor device according to claim 1 or 2, wherein: The elastic support portion is a part of the elastic body.

4. The load sensor device according to claim 1 or 2, wherein: A rigid plate portion is provided between the elastic body and the rigid pressing portion.

5. The load sensor device according to claim 1 or 2, wherein: The load sensor element has: a displacement portion that is displaced by the load borne by the pressure-receiving portion; and The plurality of piezoresistive elements electrically detect the displacement of the displacement portion.

6. The load sensor device according to claim 1 or 2, wherein: The rigid pressing portion is made of metal.

7. The load sensor device according to claim 1 or 2, wherein: The rigid pressing portion is made of silicon.

8. The load sensor device according to claim 1 or 2, wherein: The elastic body is metal.

9. The load sensor device according to claim 1 or 2, wherein: The above-mentioned elastomer has: a first contact portion including a first contact point bearing a load; a second contact portion, comprising a second contact point in contact with the rigid pressing portion; and The vertical piece is provided between the first contact portion and the second contact portion, and is used to set a space between the first contact portion and the second contact portion. When a load is applied to the pressing member, the second contact portion is elastically deformed toward the space due to a resistance force from the rigid pressing portion.

10. The load sensor device according to claim 9, wherein The first contact portion, the second contact portion, and the upright piece are integrated by a metal plate.

11. The load sensor device according to claim 1 or 2, wherein: Also features: The integrated circuit is housed in the housing and carries the load sensor element.

12. The load sensor device according to claim 1 or 2, wherein: The housing is provided with a restriction portion that restricts movement of the rigid pressing portion in a direction perpendicular to a pressing direction.

13. The load sensor device according to claim 1 or 2, wherein: Also features: The cover is disposed on the side of the pressing member opposite to the housing and applies a load to the elastic body.

14. The load sensor device according to claim 13, wherein The cover portion is provided with a convex portion that contacts the elastic body.

15. The load sensor device according to claim 14, wherein The elastic body is integrally formed with the convex portion, or the elastic body is connected to the convex portion.

16. The load sensor device according to claim 13, wherein Also features: The stopper limits the relative distance between the cover and the housing.

17. The load sensor device according to claim 1, wherein The rigid pressing portion and the elastic supporting portion are formed of the same member, and the elastic supporting portion includes a leaf spring portion.

18. The load sensor device according to claim 17, wherein The elastic support portion includes a frame portion in contact with the housing and an arm portion connecting the frame portion and the rigid pressing portion. The arm portion functions as the leaf spring portion and is symmetrically arranged with respect to the rigid pressing portion.

19. The load sensor device according to claim 1, wherein When a load is applied to the pressing component, the elastic body in direct contact with the component applying the load is deformed, thereby stabilizing the contact state between the component applying the load and the elastic body. The elastic body, whose contact state with the component applying the load has been stabilized, elastically deforms the elastic supporting portion while displacing the rigid pressing portion in a manner close to the pressure-receiving portion.

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