JP2007127580A - Strain detector - Google Patents

Abstract

An object of the present invention is to prevent an internal stress from being generated in a strain resistance element even when a strain detection device is mounted in a state of being shifted laterally or obliquely with respect to a counterpart fixing member, and an output signal is not generated. An object of the present invention is to provide a stable strain detection apparatus.
By providing an upper buffer member 35 and a lower buffer member 38 in a mounting hole 34 in the mounting plate 32, the mounting plate 32 is swingably mounted to a first counterpart fixing member 49, thereby outputting an output signal. Is intended to stabilize.
[Selection] Figure 5

Description

  The present invention relates to a strain detection apparatus that detects strain generated by applying a load.

  This type of conventional strain detection apparatus has a configuration as shown in FIGS.

  FIG. 8 is a bottom view of a conventional strain detection device, and FIG. 9 is a perspective view of the strain detection device.

  8 and 9, reference numeral 1 denotes an insulating substrate made of an elastic material, and the insulating substrate 1 is fixed to the lower surface of the pressing member 2. Further, four strain resistance elements 3 are provided on the lower surface of the insulating substrate 1, and these strain resistance elements 3 are electrically connected to a pair of power supply electrodes 4, a pair of output electrodes 5, and a pair of GND electrodes 6, respectively. A bridge circuit is configured by connecting to.

  Next, the operation of the conventional strain detection apparatus configured as described above will be described.

  As shown in FIG. 10, the conventional strain detection device is fixed to the mating fixing member 7 using a male screw 8. In this fixed state, the pressing member 2 is placed on the upper surface of the substantially central portion of the insulating substrate 1. When a pressing force is applied by this, a bending moment is generated in the insulating substrate 1 by this pressing force, and a bending moment is also generated in the four strain resistance elements 3 provided on the lower surface of the insulating substrate 1 by this bending moment. To do. When a bending moment is generated in the strain resistance element 3, the resistance value of the strain resistance element 3 changes. Therefore, the change in resistance value is output to an external computer (not shown) or the like by the pair of output electrodes 5, The pressing force applied to the insulating substrate 1 is measured.

As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.
JP-A-8-87375

  However, in the above-described conventional configuration, when the strain detection device is fixed to the counterpart fixing member 7 with the male screw 8, the pressing member 2 is displaced laterally or obliquely with respect to the counterpart fixing member 7. When attached, since internal stress is generated in the insulating substrate 1, internal stress is also generated in the strain resistance element 3, so that even when no pressing force is applied to the pressing member 2, An output signal as if a pressing force is loaded is detected from the output electrode 5, so that the output signal of the strain detection device becomes unstable.

  The present invention solves the above-described conventional problems, and internal stress is generated in the strain resistance element even when the strain detection device is mounted in a state shifted laterally or obliquely with respect to the counterpart fixing member. Rather, it is an object to provide a distortion detection apparatus in which an output signal is stable.

  In order to achieve the above object, the present invention has the following configuration.

  According to the first aspect of the present invention, an insulation having at least two strain resistance elements provided on the upper surface, a circuit pattern electrically connected to the strain resistance elements, and a detection hole provided substantially at the center. A substrate, a support member that supports the outer peripheral side of the insulating substrate, a pressing member that is inserted into the detection hole in the insulating substrate and supports the periphery of the detection hole so as to be vertically displaceable with respect to the support member, and the support And a mounting plate provided with a pair of mounting holes for fixing the member, and by mounting a buffer member on the mounting hole in the mounting plate, the mounting plate is swingably mounted on the counterpart fixing member. According to the configuration, by providing the buffer member in the mounting hole in the mounting plate, the mounting plate is swingably mounted on the counterpart fixing member, so that the pressing member is in the lateral direction with respect to the counterpart fixing member. Even if it is mounted in a state of being shifted in an oblique direction, the buffer member absorbs the shift amount, and the mounting plate that fixes the buffer member depends on the shift amount of the counterpart fixing member. As a result, the support member is not subjected to stress during mounting, so that no internal stress is generated in the insulating substrate, and as a result, internal stress is also generated in the strain resistance element. Therefore, the output signal of the distortion detection device can be stabilized.

  The invention according to claim 2 of the present invention is such that, in particular, the buffer member is made of rubber, and according to this configuration, since the buffer member is made of rubber, the pressing member is pressed against the mating fixing member. Even if it is attached in a state where it is displaced laterally or obliquely, the cushioning member made of rubber is easily deformed and has an appropriate hardness, so that the cushioning member can be reliably swung to the mounting plate It has the effect that it can be attached to.

  In the invention according to claim 3 of the present invention, in particular, the cushioning member is composed of a pair of upper cushioning members and a pair of lower cushioning members, and a step is provided on each of the upper cushioning member and the lower cushioning member. Thus, a convex portion is provided at the tip, and both the convex portions of the upper buffer member and the lower buffer member are fitted into the mounting holes in the mounting plate, and the upper buffer member and the lower buffer member are attached to the mounting plate. Thus, according to this configuration, the upper cushioning member and the lower cushioning member are each provided with a step to provide a convex portion at the tip, and both the convex portions of the upper cushioning member and the lower cushioning member are provided on the mounting plate. Since the upper cushioning member and the lower cushioning member are attached to the mounting plate by fitting in the mounting holes, the upper cushioning member and the lower cushioning member are temporarily fixed to the mounting plate. It can be attached member and the lower cushioning member on the mating mounting member, thereby, the mounting plate via a buffer member and has a effect that can be easily attached to the mating fixing member.

  In the invention according to claim 4 of the present invention, in particular, the buffer member is constituted by a cylindrical member and an insertion member provided with a convex portion so as to be inserted on the inner diameter side of the cylindrical member, and the insertion member is attached. The buffer member is attached to the mounting plate by fitting it inside the cylindrical member through the mounting hole in the plate. According to this configuration, the insertion member in the buffer member is cylindrical through the mounting hole in the mounting plate. Since the buffer member is attached to the attachment plate by fitting it inside the member, even if the plate thickness of the attachment plate is thin, the inside of the cylindrical member and the convex part of the insertion member are fitted together The buffer member can be attached to the mounting plate without being affected by the thickness of the mounting plate.

  In the invention described in claim 5 of the present invention, in particular, the buffer member is attached to the mounting plate by providing a groove portion on the entire outer surface of the buffer member and positioning the mounting hole in the mounting plate in the groove portion. According to this configuration, since the buffer member is attached to the mounting plate by providing the groove on the entire outer surface of the buffer member and positioning the mounting hole in the mounting plate in the groove, the insulating substrate This has the effect of reducing the number of parts of the cushioning member for preventing internal stress from being generated.

  As described above, in the strain detection device of the present invention, since the mounting plate is swingably mounted on the mating fixing member by providing the buffer member in the mounting hole in the mounting plate, it presses against the mating fixing member. Even if the member is mounted in a state where it is displaced laterally or obliquely, the buffer member absorbs the amount of shift, and the mounting plate fixing the buffer member is the amount of shift of the mating fixing member Accordingly, the support member is not subjected to any stress during mounting, so that no internal stress is generated on the insulating substrate. Since no stress is generated, there is an excellent effect that the output signal of the strain detection device can be stabilized.

(Embodiment 1)
Hereinafter, the invention described in the first to third aspects of the present invention will be described using the first embodiment.

  1 is an exploded perspective view of a strain detection device according to Embodiment 1 of the present invention, FIG. 2 is a side sectional view of the strain detection device, FIG. 3 is a bottom view of an insulating substrate in the strain detection device, and FIG. The bottom view which shows the state which removed the protective layer in a board | substrate, FIG. 5 is a sectional side view which shows the state which attached the distortion detection apparatus to the other party fixing member.

  1 to 5, reference numeral 11 denotes an insulating substrate made of stainless steel containing about 0.1% by weight of nickel. The insulating substrate 11 is provided with a detection portion 13 having a detection hole 12 at a substantially central position, and a circuit. A substantially rectangular mounting portion 15 for mounting the component 14 is provided. On the lower surface of the mounting portion 15, as shown in FIG. 4, a power electrode 16 made of silver, a GND electrode 17, a pair of output electrodes 18, A bridge circuit configured by electrically connecting the four compression-side strain resistance elements 19 and the tension-side strain resistance elements 20 with a circuit pattern 21 is provided. Further, the compression side strain resistance element 19, the tension side strain resistance element 20 and the circuit pattern 21 on the lower surface of the insulating substrate 11 are covered with a protective layer 22 shown in FIG. Reference numeral 23 denotes a first pressing member made of a stainless material containing about 4% by weight of nickel. The first pressing member 23 is in contact with the vicinity of the detection hole 12 on the lower surface of the insulating substrate 11. 24, and a male screw 25 is provided over the upper outer surface as shown in FIG. Reference numeral 26 denotes a second pressing member made of metal. The second pressing member 26 is provided with a penetrating female screw 27 to be combined with the male screw 25 in the first pressing member 23 at a substantially center, and a convex portion 28 on the lower surface. The insulating substrate 11 is sandwiched between the contact portion 24 of the first pressing member 23 and the convex portion 28 of the second pressing member 26.

  29 is a support member made of metal, and this support member 29 is provided with a substrate support portion 30 on the upper surface, and the substrate support portion 30 supports the outer periphery of the detection portion 13 in the insulating substrate 11 in the same plane. ing. The insulating substrate 11 sandwiched between the first pressing member 23 and the second pressing member 26 is attached to the substrate support portion 30 of the support member 29 so as to be vertically displaceable. Further, an insertion convex portion 31 is provided on the lower surface of the support member 29 so as to protrude downward. Reference numeral 32 denotes a mounting plate made of metal. The mounting plate 32 is provided with an insertion hole 33 at a substantially center, and the insertion convex portion 31 of the support member 29 is fitted into the insertion hole 33. In addition, attachment holes 34 are provided on both ends of the attachment plate 32.

  Reference numeral 35 denotes a rubber upper cushioning member. The upper cushioning member 35 is provided with a step 36 on the lower side to provide a convex portion 36 at the tip, and further provided with a hole 37 from the upper surface to the lower surface. Reference numeral 38 denotes a rubber lower cushioning member. The lower cushioning member 38 is provided with a step 39 on the upper side to provide a convex portion 39 at the tip, and further provided with a hole 40 from the upper surface to the lower surface. . Then, the projection 36 of the upper buffer member 35 is inserted and fitted into the mounting hole 34 in the mounting plate 32 from above, and the projection 39 of the lower buffer member 38 is inserted and fitted from below. ing. That is, the mounting hole 34 in the mounting plate 32 is configured to be sandwiched between the upper buffer member 35 and the lower buffer member 38. Reference numeral 41 denotes a case. The case 41 is provided with a connector portion 42 so as to protrude outward, and three connector terminals 43 are provided inside the connector portion 42. The connector terminal 43 is electrically connected to the circuit component 14 on the insulating substrate 11.

  Next, a method for assembling the strain detection apparatus according to Embodiment 1 of the present invention configured as described above will be described.

  First, a glass paste (not shown) is printed on the upper surface of a stainless steel plate (not shown), and then baked at about 850 ° C. for about 10 minutes to form the insulating substrate 11.

  Next, a silver paste (not shown) is printed on the upper surface of the insulating substrate 11 and baked at about 850 ° C. for about 10 minutes. The power electrode 16, the GND electrode 17, A pair of output electrodes 18 and a circuit pattern 21 are formed.

  Next, a metal glaze paste (not shown) is printed on the upper surface of the insulating substrate 11 at a position where the compression side strain resistance element 19 and the tension side strain resistance element 20 are provided, and then dried at about 130 ° C. for about 10 minutes. .

  Next, the insulating substrate 11 is baked at about 850 ° C. for about 10 minutes to form four compression side strain resistance elements 19 and four tension side strain resistance elements 20 on the insulating substrate 11.

  Next, a paste made of glass (not shown) is printed on the upper surface of the insulating substrate 11 so as to cover the power electrode 16, the GND electrode 17, and the pair of output electrodes 18 of the insulating substrate 11, and then about 640 ° C. After baking for 10 minutes, a protective layer 22 is formed on the upper surface of the insulating substrate 11 as shown in FIG.

  Next, after inserting the male screw 25 of the first pressing member 23 from below the detection hole 12 of the insulating substrate 11, the contact portion 24 is brought into contact with the lower surface of the insulating substrate 11.

  Next, the abutting portion 24 of the first pressing member 23 and the second pressing member 26 are engaged with the male screw 25 of the first pressing member 23 by screwing the through female screw 27 of the second pressing member 26. The insulating substrate 11 is sandwiched between the projections 28 in the.

  Next, it installs in the board | substrate support part 30 of the supporting member 29 so that the outer peripheral part whole area | region of the lower surface in the detection part 13 of the insulated substrate 11 may be supported, and it adheres by laser irradiation and welding.

  Next, after mounting the case 41 so as to cover the outer periphery of the mounting portion 15 of the insulating substrate 11 on which the circuit components 14 are previously mounted, the connector terminals 43 in the case 41 are soldered to the insulating substrate 11.

  Finally, the convex portion 36 of the upper buffer member 35 is inserted into the mounting hole 34 of the mounting plate 32 from the upper side so as to sandwich the mounting hole 34 of the mounting plate 32 from above and below, and the convex portion 39 of the lower buffer member 38. Is inserted into the mounting hole 34 of the mounting plate 32 from below, and the upper buffer member 35 and the lower buffer member 38 are fitted to the mounting plate 32.

  Next, the operation of the strain detection apparatus according to Embodiment 1 of the present invention constructed and assembled as described above will be described.

  First, as shown in FIG. 5, a hole 37 in the upper buffer member 35 holding the mounting plate 32, a mounting hole 34 in the mounting plate 32, a hole in the lower buffer member 38 and the first mating member 49. After the stepped bolt 44 is inserted through 43 from above, the nut 45 is screwed into the stepped bolt 44 to be attached to the first mating fixing member 49 via the upper buffer member 35 and the lower buffer member 38. A plate 32 is attached.

  Next, the first pressing member 23 is inserted into the hole 47 of the second mating fixing member 46 from below, and the nut 48 is screwed into the male screw 25 so that the first pressing member 23 is inserted. Is attached to the second counterpart fixing member 46.

  In this state, when a load is applied to the second mating fixing member 46, a force is applied to the assembled first pressing member 23 and is sandwiched between the first pressing member 23 and the second pressing member 26. When the insulating substrate 11 is displaced in the vertical direction, the resistance values of the compression-side strain resistance element 19 and the tension-side strain resistance element 20 vary, and the circuit component 14 performs signal processing on the variation of the resistance value, thereby outputting an output. A signal is output to the outside via the connector terminal 43.

  Here, considering the case where the second counterpart fixing member 46 is attached in a state where the second counterpart fixing member 46 is displaced laterally or obliquely, in the strain detection device according to Embodiment 1 of the present invention, By providing the upper buffer member 35 and the lower buffer member 38 in the mounting hole 34, the mounting plate 32 is swingably mounted to the first mating fixing member 49, and therefore the second mating fixing member 46. Even if the first pressing member 23 is attached in a state where it is displaced laterally or obliquely, the upper cushioning member 35 and the lower cushioning member 38 absorb the displacement, and this upper side The mounting plate 32 that fixes the buffer member 35 and the lower buffer member 38 moves by an equal amount according to the amount of displacement of the first mating side fixing member 49, whereby the support member Since no stress is applied to 9, no internal stress is generated in the insulating substrate 11. As a result, no internal stress is generated in the compression side strain resistance element 19 and the tension side strain resistance element 20. This has the effect of stabilizing the output signal of the distortion detection device.

  In addition, since the upper buffer member 35 and the lower buffer member 38 are made of rubber, the first pressing member 23 is attached to the second mating fixing member 46 with the first pressing member 23 being displaced laterally or obliquely. Even if the upper cushioning member 35 and the lower cushioning member 38 made of rubber are easily deformed and have an appropriate hardness, the upper cushioning member 35 and the lower cushioning member 35 are securely attached to the mounting plate 32. 38 has the effect that it can be attached to be swingable.

  Further, the upper buffer member 35 and the lower buffer member 38 are each provided with a step, thereby providing a convex portion 36 and a convex portion 39 at the tip, and both the convex portions 36 of the upper buffer member 35 and the lower buffer member 38. Since the upper buffer member 35 and the lower buffer member 38 are attached to the mounting plate 32 by fitting the protrusion 39 to the mounting hole 34 in the mounting plate 32, the upper buffer member 35 and the lower buffer member 35 are attached to the mounting plate 32. With the member 38 temporarily fixed, the upper cushioning member 35 and the lower cushioning member 38 can be separately attached to the first mating member fixing member 49, whereby the mounting plate 32 is attached to the upper cushioning member 35 and the lower cushioning member 49. This has the effect that it can be easily attached to the first counterpart fixing member 49 via the buffer member 38.

(Embodiment 2)
Hereinafter, the invention according to the fourth aspect of the present invention will be described with reference to the second embodiment.

  FIG. 6 is a side sectional view showing a state in which the strain detection device according to Embodiment 2 of the present invention is attached to the counterpart fixing member. In the second embodiment of the present invention, components having the same configurations as those of the first embodiment of the present invention described above are denoted by the same reference numerals, description thereof is omitted, and different points are provided. I will explain only.

  In FIG. 6, reference numeral 51 denotes a cylindrical cylindrical member made of rubber, and this cylindrical member 51 is provided on the upper surface of the mounting plate 32. 52 is a rubber insertion member, and this insertion member 52 is provided with a convex portion 53 by providing a step on the upper side. In the second embodiment of the present invention, as shown in FIG. 6, the convex portion 53 of the insertion member 52 is formed on the inner side of the cylindrical member 51 from below the attachment plate 32 through the attachment hole 34 in the attachment plate 32. The buffer member 54 composed of the cylindrical member 51 and the insertion member 52 is attached to the attachment plate 32 by being fitted to each other.

  In the second embodiment of the present invention, the buffer member 54 is attached to the mounting plate 32 by fitting the insertion member 52 of the buffer member 54 inside the cylindrical member 51 via the mounting hole 34 in the mounting plate 32. Therefore, even when the plate thickness of the mounting plate 32 is thin, the projections 53 of the insertion member 52 are fitted to the inside of the cylindrical member 51 so that the buffer plate is not affected by the thickness of the mounting plate 32. This has the effect that the member 54 can be attached to the attachment plate 32.

(Embodiment 3)
The third aspect of the present invention will be described below with reference to the third embodiment.

  FIG. 7 is a side sectional view showing a state in which the strain detection device according to Embodiment 3 of the present invention is attached to the counterpart fixing member. In the third embodiment of the present invention, components having the same configurations as those of the first embodiment of the present invention described above are denoted by the same reference numerals, description thereof is omitted, and different points are provided. I will explain only.

  That is, in the third embodiment of the present invention, as shown in FIG. 7, a groove portion 62 is provided over the entire outer surface of the rubber cushioning member 61, and the groove portion 62 is positioned in the attachment hole 34 in the attachment plate 32. Thus, the buffer member 61 is attached to the attachment plate 32.

  In the third embodiment of the present invention, the groove 62 is provided on the outer surface of the buffer member 61 over the entire circumference, and the mounting hole 34 in the mounting plate 32 is positioned in the groove 62, so that the buffer member is mounted on the mounting plate 32. Since 61 is attached, the number of parts of the buffer member 61 for preventing internal stress from being generated in the insulating substrate 11 can be reduced.

  The strain detection device according to the present invention has an effect of providing a strain detection device in which an output signal is stable, and can be applied to a use for detecting a seat weight of an automobile or the like.

1 is an exploded perspective view of a strain detection apparatus according to Embodiment 1 of the present invention. Side sectional view of the strain detector Bottom view of insulating substrate in the strain detector Bottom view showing a state where the protective layer is removed from the insulating substrate Side sectional view showing a state in which the strain detection device is attached to the counterpart fixing member Side sectional view which shows the state which attached the distortion | strain detector in Embodiment 2 of this invention to the other party fixing member. Side sectional view which shows the state which attached the distortion | strain detector in Embodiment 3 of this invention to the other party fixing member. Bottom view of a conventional strain detector Perspective view of the strain detection device Side sectional view showing a state in which the strain detection device is attached to the counterpart fixing member

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Insulation board | substrate 12 Detection hole 19,20 Strain resistance element 21 Circuit pattern 23,26 Press member 29 Support member 32 Mounting plate 34 Mounting hole 35 Upper buffer member 36,39 Convex part 38 Lower buffer member 46,49 Opposite side fixing member 51 Cylindrical member 52 Insertion member 53 Convex part 54, 61 Buffer member 62 Groove part

Claims (5)

At least two strain resistance elements are provided on the upper surface, a circuit pattern that is electrically connected to the strain resistance elements is provided, and an insulating substrate having a detection hole substantially at the center is supported, and an outer peripheral side of the insulating substrate is supported. A support member, a pressing member that is inserted into the detection hole in the insulating substrate and supports the periphery of the detection hole so as to be vertically displaceable with respect to the support member, and the support member is fixed and a pair of mounting holes are provided. A strain detecting device including a mounting plate, wherein a buffer member is provided in a mounting hole in the mounting plate, so that the mounting plate is swingably mounted on the counterpart fixing member. The strain detection device according to claim 1, wherein the buffer member is made of rubber. The cushioning member is composed of a pair of upper cushioning members and a pair of lower cushioning members, and each upper cushioning member and lower cushioning member is provided with a step to provide a convex portion at the tip, and the upper cushioning member The strain detecting device according to claim 1, wherein both convex portions of the lower buffer member and the lower buffer member are fitted into mounting holes in the mounting plate, and the upper buffer member and the lower buffer member are mounted on the mounting plate. The buffer member is composed of a cylindrical member and an insertion member provided with a convex portion so as to be inserted on the inner diameter side of the cylindrical member, and the insertion member is fitted inside the cylindrical member through a mounting hole in the mounting plate. The strain detection apparatus according to claim 1, wherein the buffer member is attached to the attachment plate. 2. The strain detecting device according to claim 1, wherein a groove is provided on the outer surface of the buffer member over the entire circumference, and the buffer member is attached to the mounting plate by positioning a mounting hole in the mounting plate in the groove.

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