JP2007255899A - Apparatus for measuring input load between suspension and vehicle body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a load-measuring apparatus capable of accurately measuring loads inputted to a vehicle body via a suspension mounted to a vehicle. <P>SOLUTION: The load-measuring apparatus for measuring loads inputted to the vehicle body via the suspension is provided with a suspension-holding part 111 for holding an upper end part of the suspension, a fixing part 113 connected to the vehicle body 131 via a plurality of connecting members (113a-113c), a plurality of strain elements (115a-115f) for connecting the suspension holding part 111 to the fixing part 113 for generating strains, according to the loads inputted to the suspension holding part 111, and strain gauges (R1-R24) each of which is mounted to the strain elements (115a-115f). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a suspension body-to-vehicle input load measuring device, and more particularly to a load measuring device that accurately measures a load input to a vehicle body via a suspension mounted on the vehicle.

  The suspension has a function as a shock absorber that attenuates a vibration load (hereinafter referred to as “load”) transmitted from the wheel to the vehicle body, and is an important device for the purpose of ride comfort of the occupant, stability of operation, and the like. For this reason, in designing the suspension, it is necessary to accurately measure the load transmitted from the suspension to the vehicle body.

  As a conventional technique for measuring a load input to a vehicle body via a suspension, a plurality of washer-type piezoelectric load sensors are provided between an upper plate fixed to the vehicle body and a lower plate fixed to the vehicle suspension. There is a method of measuring a load input from a suspension to a vehicle body using a load measuring device (Patent Document 1).

  However, although the above prior art is highly sensitive to the alternating current component of the load input from the suspension to the vehicle body, since the sensitivity to the direct current component is extremely low, it is caused by the wheel load (the vertical load applied to the road surface through the wheel). There is a problem that the load received by the vehicle body cannot be measured accurately.

In addition, a moment is usually applied to the suspension according to the road surface condition. However, in the above-mentioned conventional technology, the load in a state where the moment is added to the measured load is measured. There is a problem that it is impossible to measure the exact wheel load.
JP-A-9-236498

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a load measuring device that can accurately measure a wheel load input to a vehicle body via a suspension. .

  In order to achieve the above object, a load measuring apparatus according to the present invention is a load measuring apparatus that measures a load input to a vehicle body via a suspension, and includes a suspension holding section that holds an upper end portion of the suspension, and a plurality of suspension measuring sections. A plurality of strain generating members that connect the fixed portion connected to the vehicle body via the connecting member, the suspension holding portion and the fixing portion, and generate strain according to the load input to the suspension holding portion. And a strain gauge attached to each strain generating body.

  Further, a strain gauge attached to the strain body forms at least one bridge circuit, and the bridge circuit removes an input of a moment from a load input to each strain gauge, and is input to the vehicle body. It is characterized by accurately measuring only the load.

  According to the load measuring apparatus according to the present invention configured as described above, since the strain gauge is used instead of the conventional piezoelectric load sensor, the load input to the vehicle body via the suspension is measured. Not only AC components but also DC components can be measured with high accuracy.

  In addition, the strain gauge attached to the strain-generating body forms a bridge circuit, and this bridge circuit is designed to remove the moment input from the load input to the vehicle body via the suspension. Can be measured.

  Hereinafter, a load measuring apparatus according to the present invention will be described in detail with reference to the drawings, divided into a first embodiment and a second embodiment. In the drawings referred to in the following embodiments, the dimensions of each member constituting the load measuring device according to the present invention are exaggerated, which is for facilitating understanding of the contents of the invention.

First Embodiment FIGS. 1 to 5 are views for explaining a load measuring apparatus according to a first embodiment of the present invention. 1 is a diagram showing a top view of the load measuring apparatus according to the present embodiment as viewed from the vehicle body side, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIG. FIG. 3b is a sectional view taken along line IIIb-IIIb in FIG. 3a, FIG. 3c is a sectional view taken along line IIIc-IIIc in FIG. 3a, and FIG. FIG. 5 is a diagram showing a schematic configuration of a bridge circuit including a plurality of strain gauges in the present embodiment.

  As shown in FIGS. 1 and 2, load measuring apparatus 100 according to the present embodiment has a structure that is sandwiched between a vehicle suspension (not shown) and vehicle body 131.

  As shown in the figure, the load measuring apparatus 100 includes a suspension holding part 111, a fixing part 113, strain generating bodies 115a to 115f, and strain gauges R1 to R24 attached to the strain generating bodies 115a to 115f.

  The suspension holding unit 111 holds a suspension that absorbs a load transmitted from a tire (not shown) of the vehicle body 131 to the vehicle body 131. A plurality of bolt holes are formed in the suspension holding portion 111, and are fixed to the upper end portion 151 of the suspension by suspension mounting bolts 111a to 111f. The suspension holding portion 111 is formed in a disk shape in the present embodiment following the shape of the upper end portion 151 of the suspension.

  The fixing portion 113 is formed so as to surround the suspension holding portion 111 and is connected to the vehicle body 131 via a plurality of connecting members.

  The fixing portion 113 is fixed to the vehicle body 131 by connecting members, for example, vehicle body fastening bolts 113a to 113c. In the present embodiment, a bolt is used as the connecting member, but the present invention is not limited to this, and the connecting member is not particularly limited as long as the fixing portion 113 and the vehicle body 131 can be connected.

  The strain generating members 115a to 115f connect the suspension holding unit 111 and the fixed unit 113, and generate strain corresponding to the load (wheel load and moment) input to the suspension holding unit 111. The strain bodies 115a to 115f are formed so as to connect the suspension holding part 111 and the fixing part 113 along the outer periphery of the suspension holding part.

  Six strain bodies 115a to 115f are formed at equal intervals with respect to the suspension holding portion 111 and the fixing portion 113, respectively. Thus, the reason why the strain generating bodies are formed at equal intervals is that the load input to the suspension holding portion 111 is distributed to each of the strain generating bodies 115a to 115f, and the strain concentration (details will be described later) is even. It is to make it. In addition, if it forms so that the positional relationship of a strain body may become equal intervals, the components which fix a vehicle body, the attachment part shape of a component, a volt | bolt, etc. will not be specifically limited.

  The strain bodies 115a to 115f are formed of a metal material, and are preferably formed of a material having high rigidity and good elastic deformation, such as a metal material forming the suspension spring 153, for example. In addition, the dimension of the cross section can be arbitrarily determined according to the mechanical characteristics such as the rigidity and allowable shear stress of the material forming the strain generating body, corresponding to the input load.

  Next, the shape of the strain generating body will be described.

  FIG. 3a is a partially enlarged view of the strain body 115a, which is one of the strain bodies. In the present embodiment, since the shape of the strain-generating body is the same, description will be given taking the strain-generating body 115a as an example.

  As shown in the figure, the strain body 115a has a certain radius of curvature on the side surface of the strain body 115a. Moreover, as shown in FIG. 3b and FIG. 3c, the inside of the strain body 115a is hollow, and its cross section is formed in a circular shape. The strain body in the present embodiment is formed by cutting a disk-shaped metal plate by wire discharge.

  The reason for forming such a shape is to prevent variation in strain generated by the strain generating body and to concentrate strain in a region where the strain gauge has high detection sensitivity.

  As shown in FIG. 3b, the region where the thickness of the strain generating body is the thinnest is the region X and the region Y. Since strain is concentrated most in this region, the strain gauge is usually attached so that this region corresponds to a region (sensing point) with high strain gauge detection sensitivity. Note that the shape of the strain generating body is not particularly limited as long as the strain can be concentrated in a region where the strain gauge has high detection sensitivity.

  By the way, the number of strain generating bodies is determined depending on the number of connecting members for fixing the fixing portion 113, that is, the number of fixed ends. Specifically, the characteristics of the vehicle body (usually, the vehicle body fastening bolts connecting the suspension are three front suspensions and two rear suspensions), the bridge circuit formed by the strain gauge, and the strain body It is determined in consideration of various factors such as the number of strain gauges to be attached and the rigidity and strength of the strain generating body (detailed description of the strain gauges and the bridge circuit will be described later).

  According to the study by the inventors, when the above factors are taken into consideration, the number of strain generating bodies is a natural number of fixed ends, preferably an even number of times.

  In the present embodiment, as shown in FIG. 1, since there are three body fastening bolts 113a to 113c, the number of strain generating bodies can be obtained by the following equation.

  It becomes.

  The strain gauges R1 to R12 and R13 to R24 are elements that are attached to the strain generating bodies 115a to 115f and detect strain generated by the strain generating bodies 115a to 115f.

  As described above, the strain gauges R1 to R12 and R13 to R24 are attached to the strain concentrated portions generated by the strain generating members 115a to 115f (see FIG. 3b), detect the strain, and receive the moment that the strain generating body receives. That is, it is attached so that torque can be measured.

  In the present embodiment, as shown in FIG. 4, a biaxial orthogonal strain gauge for torque measurement composed of two strain gauges is used. The upper strain gauge 411 (the one closer to the vehicle body) shown in FIG. 4 corresponds to the strain gauges R1 to R12, and the lower strain gauge 413 (the one closer to the suspension side) corresponds to the strain gauges R13 to R24 (see FIG. 4). See FIG. 3b).

  As is well known, the torque measurement method using strain gauges is measured at two measurement points so that the two strain gauges are inclined 45 degrees with respect to the axial direction, and the respective strain gauges are in a biaxial orthogonal state. It is also possible to attach to.

  Further, as shown in FIG. 4, it is preferable that the vertical length L ′ of the strain gauge has the same dimension as the vertical length L of the attachment surface (side surface) of the strain generating body shown in FIG. This is because by making the mounting surface dimensions of the strain-generating body the same as the dimensions of the strain gauge, displacement of the mounting position due to manual work can be prevented, measurement errors can be reduced, and measurement accuracy can be improved. Because it can.

  By the way, the load measuring apparatus 100 is mounted in advance on a component 171 in which the upper end portion 151 of the suspension and the suspension holding portion 111 are integrated by the processing portion 161 and fixed by suspension mounting bolts 111a to 111f. It is comprised so that it may be inserted | pinched between. By adopting such a configuration, it is possible to offset the upper end portion 151 of the suspension upward (to the vehicle body side) as compared with the case where the load measuring device 100 is simply sandwiched, and the change in the vehicle height when the load measuring device is mounted can be reduced. Can be reduced.

  In addition, the attachment of each of the above-mentioned parts is performed by attaching three load fixing bolts 113a to 113c to the load measuring device 100 and the vehicle body 131, and attaching six suspension attachment bolts 111a to 111f to the suspension holding part 111 and the suspension. Although the method used has been described, the present invention is not limited to this, and as shown in FIG. 1, the strain generating bodies 115a to 115f are formed at equal intervals in the positional relationship with the strain generating bodies 115a to 115f. If so, the number of the vehicle body fastening bolts and suspension mounting bolts is arbitrary.

  Next, the bridge circuit constituted by the strain gauges R1 to R12 and R13 to R24 of the present embodiment will be described in detail. In the following description, the case where the number of strain generating bodies is six (the number of body fastening bolts is three) will be described, but the present invention is not limited to this.

  Referring back to FIG. 1 and FIGS. 3a to 3c, the strain gauge used in the present embodiment is a biaxial orthogonal strain gauge, 12 on the side surfaces of the six strain bodies 115a to 115f, a total of 24 strain gauges. Strain gauges R1 to R12 and R13 to R24 are attached. Two bridge circuits are formed by these strain gauges.

  The reference number of the strain gauge in FIG. 1 is based on the one strain gauge (R1) closest to the one fixed end (body fastening bolt 113a) as a reference, and the one closer to the vehicle body sequentially in the clockwise direction. Are indicated as R1 to R12, and those closer to the suspension side are indicated as R13 to R24.

  FIG. 5 is a configuration diagram of a bridge circuit in the present embodiment.

  As shown in FIG. 5, the bridge circuit in the present embodiment is configured by two bridge circuits. The bridge circuit A is composed of a group of side strain gauges (R1, R2, R5, R6, R9, R10, R13, R14, R17, R18, R21, R22) that are close to each fixed end. The circuit B is composed of strain gauge groups (R3, R4, R7, R8, R11, R12, R15, R16, R19, R20) on the side far from each fixed end.

  Next, the strain gauges arranged in the respective bridge circuits will be described.

As shown in FIG. 5, in a clockwise direction, sequentially, strain gauge R9, R5, R1 is the side _{A 1} of the bridge circuit A, gauges R13, R17, R21 strain on sides _{A 2} is side _{A 3} strain gauge R10, R6, R2 is, strain gauges R14, R18, R22 are arranged on the side _{A 4.}

Similarly, the side B ₁ of the bridge circuit B has strain gauges R11, R7, R3, the side B ₂ has strain gauges R15, R19, R23, and the side B ₃ has strain gauges R12, R8, R4. B ₄ is provided with strain gauges R16, R20, and R24.

The strain gauges disposed on the side A ₁ and the side A ₃ facing the side A ₁ of the bridge circuit A are on the side where the strain generating body is compressed by a load input from the suspension (hereinafter referred to as “compression side”). Strain gauge. On the other hand, the strain gauges arranged on the side A ₂ and the side A ₄ facing the side A ₂ are strain gauges on the side where the strain generating body is pulled by a load input from the suspension (hereinafter referred to as “tensile side”). It is. The bridge circuit B has the same arrangement configuration.

  In addition, as shown in FIG. 5, one strain gauge disposed on one side and a line symmetric with respect to a straight line connecting the contact M and the contact N are arranged at positions corresponding to the one strain gauge. The other strain gauges to be arranged are strain gauges attached to the compression side and the tension side of the same strain generating body. For example, the strain gauge R1 (tensile side) and the strain gauge R13 (compression side) attached to the strain body 115a are arranged at symmetrical positions with respect to a straight line connecting the contact point M and the contact point N in the bridge circuit A. ing.

Here, the positional relationship of the strain gauges arranged on each side of the bridge circuit will be described. Hereinafter, Strain gauge described is disposed on a side A ₁ of the bridge circuit A.

Refer to FIG. 1 again. As shown in FIG. 1, when viewed from the central axis of the suspension holder 111 in a clockwise direction, the strain gauges R9 are arranged in the side A ₁ is the right side surface of the strain body 115 d, strain gauges R5 is strain member The strain gauge R1 is attached to the right side surface of the strain body 115a on the right side surface of 115c. This positional relationship is attached so that a substantially equilateral triangle is formed by connecting the positions where the respective strain gauges are attached by straight lines. The positional relationship of each side is the same.

  If the bridge circuit as described above is formed, it is possible to remove only the moment input from the load input from the suspension to the vehicle body, that is, the load input to the strain generating members 115a to 115f via the suspension holding portion 111. it can.

  The presence or absence of output by the bridge circuit is confirmed by the following formula (2), and it can be confirmed by formula (2) that only the moment input is removed from the load input from the suspension. Equation (2) is calculated by geometrically calculating the amount of strain generated for each strain gauge.

Here, ε _Vout is a strain output amount of the load measuring device 100, ε _BA and ε _BB are strain output amounts of each bridge circuit, and ε _{1 to} ε ₂₄ are strain output amounts of the strain gauges R1 to R24. .

In addition, the first item of the formula (2) is the strain output amount of the strain gauges arranged on the sides A ₁ and A ₃ of the bridge circuit A, and the second item is arranged on the sides A ₂ and A ₄ of the bridge circuit A. The third item is the strain output amount of the strain gauge disposed on the sides B ₁ and B ₃ of the bridge circuit B, and the fourth item is the side B ₂ and side B of the bridge circuit B. _The value obtained by adding and averaging the strain output amounts of strain gauges arranged in ₄ is shown.

Then, as described above, the sides A _1, side A _3, sides B _1, and the output amount of strain gauges are disposed on a side B ₃ is the output of the tension side, the side A _2, side A _4, sides Since the output amount of the strain gauge arranged at B ₂ and the side B ₄ is the output amount on the compression side, the output ε _Vout of the load device main body 100 is the output amount of each strain gauge arranged at each side, That is, a value obtained by adding and averaging the outputs of the bridge circuit A and the bridge circuit B is shown.

  By forming the bridge circuit as described above, the moment can be removed from the load input from the suspension.

  By the way, the reason for using the two bridge circuits configured as described above is as follows.

  Even if two bridge circuits are not used, the moment can usually be removed only by a circuit configuration like the bridge circuit A.

  However, there is a case where the moment input cannot be removed only by the bridge circuit A. In this case, a potential difference (for example, +1 volt) that should not be output from one bridge circuit is output, but another bridge circuit outputs a potential difference (for example, -1 volt) whose sign is opposite to that of the potential difference. . As a result, the output of the bridge circuit as a whole is an output from which the moment input is removed.

Second Embodiment FIGS. 6 to 8 are views for explaining a load measuring apparatus according to a second embodiment of the present invention. 6 is a diagram showing a top view of the load measuring apparatus according to the present embodiment as viewed from the vehicle body side, FIG. 7 is a sectional view taken along line IIV-IIV in FIG. 6, and FIG. It is a figure which shows schematic structure of the bridge circuit comprised with a some strain gauge. Note that the first embodiment differs from the second embodiment mainly in the number of strain generating bodies in FIG. 6 corresponding to FIG. The other components are exactly the same as those in FIG. 1, and the description of those components is omitted. Further, in FIG. 6, the difference in function of each element due to the difference in the number of strain generating bodies from that in FIG. 1 will be described only for the different points.

  Moreover, although the following description demonstrates the case where there are four strain bodies (two body fastening bolts), the present invention is not limited to this.

  As shown in FIGS. 6 and 7, the load measuring apparatus 200 according to the present embodiment is different from the first embodiment in that the vehicle body mounting component at the upper end of the suspension (not shown) is a load measuring apparatus. It has become a form replaced by. The load measuring device 200 is attached to the suspension and then attached to the vehicle body by a connecting member. In the present embodiment, as shown in FIG. 7, the attachment to the vehicle body 251 uses two nuts of vehicle body retaining nuts 213a and 213b as connecting members, and suspension mounting bolts 251a and 251b included in the vehicle body 251. The four strain-generating members 215a to 215d (two connecting members × 2 times) are employed. In the present embodiment, unlike the first embodiment, eight strain gauges R ′ 1 to R ′ 16 are attached to the side surface of the strain generating body, for a total of 16 strain gauges.

  The reference number of the strain gauge in FIG. 6 is based on the one strain gauge (R′1) closest to the one fixed end (body fastening nut 213a) as a reference, and sequentially toward the vehicle body in the clockwise direction. The closer one is indicated as R′1 to R′8, and the closer one to the suspension side is indicated as R′9 to R′16.

  Further, in the present embodiment, the suspension holding portion of the first embodiment is configured such that deformation of each portion other than the strain generating bodies 215a to 215d due to load input is reduced as much as possible so that strain is concentrated on the strain generating bodies 215a to 215d. The shape is different from 111. The suspension holding portion 211 has four convex portions formed at equal intervals along the periphery of the disk shape.

  Next, the bridge circuit constituted by the strain gauges R′1 to R′16 of the present embodiment will be described in detail.

  FIG. 8 is a configuration diagram of a bridge circuit in the present embodiment.

  As shown in FIG. 8, the bridge circuit in the present embodiment includes two bridge circuits. The bridge circuit A ′ includes a side strain gauge group (R′1, R′4, R′5, R′8, R′9, R′12, R′13, R ′) that are close to each fixed end. 16), on the other hand, the bridge circuit B ′ is composed of strain gauge groups (R′2, R′3, R′6, R′7, R ′) on the side far from each fixed end. 10, R′11, R′14, R′15).

  Next, the strain gauges arranged in the respective bridge circuits will be described.

As shown in FIG. 8, in a clockwise direction, sequentially, gauge R'5 strain in ₁ 'side A' of the bridge circuit A, R'1 is, side A 'gauge R'9 strain in _2, R' 13, strain gauges R ′ ₄ and R ′ 8 are arranged on the side A ′ _3, and strain gauges R ′ 16 and R ′ 12 are arranged on the side A ′ ₄ . On the other hand, the gauge R'7 strain in ₁ 'side B' of the bridge circuit B, R'3 is, the side B 'gauge R'11 strain in _2, R'15 is, the side B ₃ strain gauge R' 2, which R'6 is gauge R'14 strain to the side B _'4, R'10 is arranged.

The strain gauges disposed on the side A ′ ₁ of the bridge circuit A and the side A ′ ₃ facing the side A ′ ₁ are strain gauges on the compression side. On the other hand, the strain gauges arranged on the side A ′ ₄ opposite to the side A ′ ₂ and the side A ′ ₂ are strain gauges on the tension side. The bridge circuit B ′ has a similar arrangement configuration.

  Further, as shown in FIG. 8, one strain gauge arranged on one side and a straight line connecting the contact M ′ and the contact N ′ are arranged on symmetrical sides and correspond to the one strain gauge. The other strain gauges arranged at the positions to be attached are strain gauges attached to the compression side and the tension side of the same strain generating body. For example, the strain gauge R′1 (tensile side) and the strain gauge R′9 (compression side) attached to the strain generating body 215a are connected to a straight line connecting the contact M ′ and the contact N ′ in the bridge circuit A ′. Are arranged in symmetrical positions.

Here, the positional relationship of the strain gauges arranged on each side of the bridge circuit will be described. The following describes 'side A' ₁ disposed in that strain gauge bridge circuit A.

Refer to FIG. 6 again. As shown in FIG. 6, when viewed from the central axis of the suspension holder 211 in a clockwise direction, the side A 'strain gauge R'1 are arranged in _one on the left side surface of the strain body 215a, the strain gauges R' 5 is attached to the left side surface of the strain body 215c. This positional relationship is a point-symmetrical positional relationship with respect to the center point of the suspension holding portion 211. The positional relationship of each side is the same.

  If the bridge circuit as described above is formed, it is possible to remove only the moment input from the load input from the suspension to the vehicle body, that is, the load input to the strain generating bodies 215a to 215d via the suspension holding portion 211. it can.

  The presence or absence of output by the bridge circuit is confirmed by the following formula (3), and it can be confirmed by formula (3) that only the moment input is removed from the load input from the suspension. In Equation (3), the amount of strain generated for each strain gauge is calculated geometrically.

Here, ε ′ _Vout is the strain output amount of the load measuring device 200, ε ′ _BA and ε ′ _BB are strain output amounts of the bridge circuits, and ε ′ _{1 to} ε ′ ₁₆ are strain gauges R′1 to R′1. This is the strain output amount of R′16.

Further, 'a ₃ strain output of the strain gauge is arranged, the second item is a bridge circuit A' ₁ and edges A 'side A' of Equation (3) first item of the bridge circuit side A A _'2 and The third item indicates the strain output amount of the strain gauge disposed on the side A ′ ₄ , the third item indicates the strain output amount of the strain gauge disposed on the side B ₁ and the side B ′ ₃ of the bridge circuit B ′, and the fourth item indicates the bridge circuit. A value obtained by adding and averaging strain output amounts of strain gauges arranged on the side B ′ ₂ and the side B ′ ₄ of B ′ is shown.

As described above, the output amount by the strain gauges arranged on the side A ′ ₁ , the side A ′ ₃ , the side B ′ ₁ , and the side B ′ ₃ is the output amount on the tension side, and the side A ′ ₂ , Since the output amounts of the strain gauges arranged on the sides A ′ ₄ , B ′ ₂ , and B ′ ₄ are the output amounts on the compression side, the output ε ′ _Vout of the load device body 200 is arranged on each side. The output amounts of the respective strain gauges, that is, the values obtained by adding and averaging the outputs of the bridge circuit A ′ and the bridge circuit B ′ are shown.

  By forming the bridge circuit as described above, the moment can be removed from the load input from the suspension.

  As described above, the load measuring device according to the present invention detects a change in the resistance value of a strain gauge attached to the strain body when the strain body receives a load input from the suspension. The detected change in resistance value amplifies the output by a bridge circuit composed of multiple strain gauges and outputs an electrical signal that cancels the moment input to each strain gauge and removes the moment input. is doing. As a result, it is possible to accurately measure not only the AC component of the load input to the vehicle body via the suspension, but also the DC component, and since only the moment input is removed from the input load, it is accurate. The wheel load can be measured.

  In addition, since a bridge circuit composed of a plurality of strain gauges is used without using a conventional piezoelectric load sensor, there is no need to remove individual differences between sensors. No adjustment mechanism or adjustment work is required, and work efficiency can be significantly improved.

  Further, by setting the number of connecting members to 2 or 3, compatibility with various vehicle types can be provided, and a load measuring device with excellent versatility can be provided.

  The present invention is useful in the technical field of measuring a load input from a suspension to a vehicle body.

It is a figure showing the upper surface which looked at the load measuring device concerning a 1st embodiment of the present invention from the body side. It is sectional drawing along the II-II line in FIG. It is the elements on larger scale of the strain body shown in FIG. It is sectional drawing along the IIIb-IIIb line | wire in FIG. 3a. It is sectional drawing along the IIIc-IIIc line | wire in FIG. 3a. It is a figure which shows the strain gauge used in 1st Embodiment of this invention. In 1st Embodiment of this invention, it is a figure which shows schematic structure of the bridge circuit comprised by several strain gauges. It is a figure which shows the upper surface which looked at the load measuring apparatus which concerns on this Embodiment from the vehicle body side. Sectional view along the IIV-IIV line in FIG. In 1st Embodiment of this invention, it is a figure which shows schematic structure of the bridge circuit comprised by several strain gauges.

Explanation of symbols

111 suspension holding part,
111a to 111c suspension mounting bolts,
113 fixing part,
113-113c body fastening bolt,
115a to 115f strain body,
R1-R24 strain gauge,
131 body
151 Upper end of suspension,
153 Suspension spring.

Claims (9)

A load measuring device for measuring a load input to a vehicle body via a suspension,
A suspension holding portion for holding an upper end portion of the suspension;
A fixed portion connected to the vehicle body via a plurality of connecting members;
A plurality of strain generating bodies that connect the suspension holding portion and the fixed portion, and generate strain according to a load input to the suspension holding portion;
A strain gauge attached to each strain body;
A load measuring device comprising:   The load measuring device according to claim 1, wherein the fixing portion is formed so as to surround the suspension holding portion.   The load measuring device according to claim 1, wherein the strain generating bodies are formed at equal intervals on an outer periphery of the suspension holding portion.   4. The load measuring device according to claim 1, wherein the number of the strain generating bodies is a natural number times the number of the connecting members.   The load measuring device according to claim 1 or 4, wherein the number of the connecting members is two or three.   The load measuring apparatus according to claim 1, wherein a strain gauge attached to the strain generating body forms at least one bridge circuit, and the bridge circuit removes an input of a moment from the load.   The load measuring device according to claim 6, wherein when the number of strain generating bodies is six, the number of bridge circuits is one or two.   The load measuring device according to claim 6, wherein when the number of strain generating bodies is four, the number of bridge circuits is two.   The load measuring apparatus according to claim 1, wherein the strain gauge is an orthogonal biaxial strain gauge for torque measurement.

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