Load cell and weighing vehicle

Abstract

The present invention provides a load cell that allows a circuit board to be placed near a strain gauge, and a vehicle equipped with a weighing function. [Solution] The load cell comprises a load cell body extending in a predetermined direction and subjected to deformation when a load is applied in a direction perpendicular to the predetermined direction; a bottomed cylindrical housing adjacent to the end of the load cell body in the predetermined direction and having an opening; a substrate housed in the housing; and a first wiring extending from the substrate to the outside of the housing. The housing comprises a cylindrical portion, a bottom closing one end of the cylindrical portion, and a notch formed in the cylindrical portion from a part of the opening toward the bottom. The first wiring passes through the notch and extends to the outside of the housing.

Description

Technical Field

[0001] This specification relates to a load cell and a vehicle with a weighing function.

Background Art

[0002] For example, Patent Document 1 below discloses a pin-type load cell including a shaft member and a shear strain gauge (hereinafter also referred to as a strain gauge) adhered to a recess formed in the shaft member.

[0003] The load cell requires a substrate for applying a predetermined voltage to the strain gauge and deriving the load applied to the load cell from the change in the voltage output from the strain gauge. However, Patent Document 1 does not disclose anything about the arrangement of such a substrate. Since the wiring connecting the substrate and the strain gauge is preferably short from the viewpoints of noise suppression and miniaturization of the load cell, it is desirable to arrange the substrate near the strain gauge.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Therefore, the problem is to provide a load cell and a vehicle with a weighing function capable of arranging a substrate near a strain gauge.

Means for Solving the Problems

[0006] The load cell includes: a load cell body extending in a predetermined direction and generating strain when a load is applied in a direction orthogonal to the predetermined direction; a bottomed cylindrical housing portion having an opening and adjacent to an end portion of the load cell body in the predetermined direction; a substrate accommodated in the housing portion; It comprises a first wiring extending from the substrate to the outside of the housing, The housing portion comprises a cylindrical portion, a bottom portion that closes one end of the cylindrical portion, and a notch formed in the cylindrical portion extending from a part of the opening toward the bottom portion. The first wiring passes through the notch and extends out of the housing.

[0007] Furthermore, vehicles equipped with weighing functions are A loading section capable of loading cargo, A vehicle section on which the aforementioned loading section is mounted, The system includes the above-mentioned load cell, which is positioned between the loading section and the vehicle section. [Brief explanation of the drawing]

[0008] [Figure 1] Overall view of the vehicle with weighing function according to this embodiment [Figure 2] Cross-sectional view illustrating the arrangement of load cells according to this embodiment. [Figure 3] Front view of the load cell according to this embodiment [Figure 4] Figure 3, section view along line IV-IV [Figure 5] Side view of the load cell according to this embodiment [Figure 6] A schematic diagram showing the wiring connections between the battery, indicator, and each load cell. [Figure 7] Functional block diagram to explain the configuration of the circuit section [Modes for carrying out the invention]

[0009] In each drawing, the dimensions of components may be enlarged or reduced from their actual dimensions for the sake of clarity, and the dimensional ratios between drawings may not be consistent. Furthermore, in each drawing, some components may be omitted for the sake of clarity.

[0010] Terms including ordinal numbers such as "1st," "2nd," etc., are used to describe various components, but these terms are used solely for the purpose of distinguishing one component from others, and the components are not particularly limited by these terms. Furthermore, the number of components including ordinal numbers is not particularly limited; for example, there may be only one. Also, the ordinal numbers used in the following specification and drawings may differ from the ordinal numbers described in the claims.

[0011] The following description will explain one embodiment of a load cell and a vehicle with a weighing function, with reference to Figures 1 to 7. Note that the following embodiment is provided as an example to aid in understanding the configuration of the load cell and the vehicle with a weighing function, and does not limit the configuration of the load cell and the vehicle with a weighing function.

[0012] In the following explanation and diagrams, the first direction D1 is also called the front-rear direction D1, the second direction D2 is also called the left-right direction D2, and the third direction D3 is also called the up-down direction D3. That is, each of the directions D1 to D3 is the direction as seen from the perspective of a person (driver) sitting in the driver's seat in the driver's cab 103a of the weighing vehicle 100 when the weighing vehicle 100 is in motion.

[0013] In the forward / backward direction D1, the direction of the arrow in the diagram is considered the forward direction, and the direction opposite to the direction of the arrow in the diagram is considered the backward direction. In the left / right direction D2, the direction of the arrow in the diagram is considered the left direction, and the direction opposite to the direction of the arrow in the diagram is considered the right direction. In the up / down direction D3, the direction of the arrow in the diagram is considered the up direction, and the direction opposite to the direction of the arrow in the diagram is considered the down direction.

[0014] As shown in Figure 1, the weighing vehicle 100 includes a loading section 101 on which loads can be loaded, a vehicle section 102 on which the loading section 101 is mounted, and a load cell 1 positioned between the loading section 101 and the vehicle section 102.

[0015] The vehicle 100 with a weighing function may include a plurality of load cells 1. For example, the vehicle 100 with a weighing function includes four load cells 1. Further, the vehicle 100 with a weighing function may include a battery 105 capable of supplying power to each load cell 1, and an indicator 106 for displaying the weighing result output from each load cell 1.

[0016] The loading section 101 may include a loading box 101a and a sub-deck frame 101b. The loading box 101a may include, for example, a loading box main body 101c having a discharge opening at the rear end, and a tailgate 101d rotatably connected to the loading box main body 101c so as to open and close the discharge opening, as in the present embodiment.

[0017] The sub-deck frame 101b is a member for reinforcing the loading box 101a and is welded to the bottom wall of the loading box 101a. The sub-deck frame 101b may be, for example, in the shape of a rectangular frame.

[0018] Further, as shown in FIG. 2, the loading section 101 may include a transmission section 101e disposed on the sub-deck frame 101b. For example, the loading section 101 may include four transmission sections 101e. The four transmission sections 101e are respectively disposed at the four corners of the rectangular frame-shaped sub-deck frame 101b.

[0019] The transmission section 101e transmits the weight of the load to the load cell 1. As shown in FIG. 2, the transmission section 101e is a block-shaped member protruding from the sub-deck frame 101b toward the vehicle section 102 (lower side). The transmission section 101e includes a through-hole 101f for the load cell. The inner diameter of the through-hole 101f for the load cell is constant, and the load cell 1 is inserted therethrough.

[0020] As shown in FIG. 1, the vehicle section 102 may include a vehicle body 103 and a swing mechanism section 104. The vehicle body 103 may include a driver's cab (also referred to as a "cab") 103a and a chassis frame 103b extending rearward from the driver's cab 103a.

[0021] The rocking mechanism 104 is a mechanism that rocks the loading section 101 relative to the chassis frame 103b. The rocking mechanism 104 may include a main frame 104a fixed to the chassis frame 103b, a deck frame 104b to which the loading section 101 is fixed, a pin 104c that rotatably connects the deck frame 104b to the main frame 104a, and a dumping device 104d that rocks the deck frame 104b relative to the main frame 104a.

[0022] The main frame 104a is a rectangular frame-shaped member that is fixed to the chassis frame 103b. The main frame 104a is a rectangular frame-shaped member that is the same size as the chassis frame 103b and is fixed to the chassis frame 103b in a state where it is superimposed on the chassis frame 103b.

[0023] The deck frame 104b is a rectangular frame-shaped member to which the loading section 101 is fixed. The rear end of the main frame 104a is connected to the rear end of the deck frame 104b, and the connection between the main frame 104a and the deck frame 104b is a hinge structure. In this hinge structure, the pin 104c extends in the left-right direction D2. As a result, the deck frame 104b rotates around the pin 104c as an axis, and the loading section 101 fixed to the deck frame 104b moves between a reference position (position shown in Figure 1) and a dump position (not shown).

[0024] Furthermore, the rocking mechanism 104 may include support parts 104e positioned on the deck frame 104b, as shown in Figure 2. The rocking mechanism 104 may, for example, include four support parts 104e. The four support parts 104e are positioned at the four corners of the rectangular frame-shaped deck frame 104b.

[0025] The support section 104e supports the load cell 1. The support section 104e may include a pair of support blocks 104f arranged on the upper surface of the deck frame 104b at intervals from each other, as shown in Figure 2. The pair of support blocks 104f may be erected on a mounting plate 104h fixed to the deck frame 104b. In the deck frame 104b of this embodiment, the pair of support blocks 104f in the front support section 104e are arranged at an interval in the left-right direction D2, and the pair of support blocks 104f in the rear support section 104e are arranged at an interval in the front-rear direction D1. Figures 2 to 5 show the rear support section 104e, the load cell 1, and the transmission section 101e.

[0026] The four support sections 104e are positioned opposite each of the four corresponding transmission sections 101e. The pair of support blocks 104f are positioned to sandwich the corresponding transmission sections 101e from both sides.

[0027] Each of the pair of support blocks 104f is provided with through-holes 104g for load cells that penetrate in opposite directions. A load cell 1, which is inserted through the load cell through-hole 101f of the transmission section 101e, is inserted through each of the pair of load cell through-holes 104g.

[0028] The vehicle section 102 is configured to mount the loading section 101 by connecting the deck frame 104b and the sub-deck frame 101b such that the deck frame 104b and the sub-deck frame 101b of the loading section 101 overlap. At this time, a gap of vertical D3 is formed between the deck frame 104b and the sub-deck frame 101b so that the weight of the loading section 101 is transmitted to the load cell 1.

[0029] As described above, the loading section 101 and the vehicle section 102 are connected via load cells 1. Specifically, the two transmission sections 101e on the front side of the subdeck frame 101b and the two support sections 104e on the front side of the deck frame 104b are each connected via load cells 1, and the two transmission sections 101e on the rear side of the subdeck frame 101b and the two support sections 104e on the rear side of the deck frame 104b are each connected via load cells 1.

[0030] As shown in Figure 2, the load cell 1 is a cylindrical member extending in the front-rear direction D1, and the magnitude of the load can be measured by detecting the strain caused by the load (in this embodiment, the weight of the load) applied to the load cell 1.

[0031] As shown in Figures 3 and 4, the load cell 1 comprises a load cell body 2 extending in the front-rear direction D1 and subject to deformation when the weight of the load is applied, a bottomed cylindrical housing 3 adjacent to the front-rear end of the load cell body 2 in the front-rear direction D1, and a strain gauge 4 fixed to the load cell body 2 and for detecting the deformation of the load cell body 2.

[0032] Furthermore, the load cell 1 includes a circuit section 5 housed in a housing section 3, and a first wiring 6 extending from the circuit section 5 to the outside of the housing section 3. Cables 107 extending from the battery 105 and the indicator 106 are connected to this first wiring 6 (see Figure 6). In addition, the load cell 1 includes a second wiring 7 connecting the strain gauge 4 and the circuit section 5.

[0033] The load cell body 2 is a substantially cylindrical member made of metal and having a central axis along the front-rear direction D1. The load cell body 2 may include a plurality of small-diameter portions 21 arranged at intervals in the front-rear direction D1, a plurality of large-diameter portions 22 arranged at intervals in the front-rear direction D1, and a connecting portion 23 arranged at one end in the front-rear direction D1. The small-diameter portions 21 are arranged between two large-diameter portions 22. For example, the load cell body 2 may include two small-diameter portions 21 and three large-diameter portions 22.

[0034] Each large-diameter section 22 has an outer diameter corresponding to the inner diameter of the load cell through holes 101f and 104g (see Figure 2). On the other hand, the small-diameter sections 21 and connecting sections 23 have smaller diameters than the large-diameter sections 22. Furthermore, each small-diameter section 21 and connecting section 23 has an outer diameter smaller than the inner diameter of each load cell through hole 101f and 104g.

[0035] A locking groove 23a is formed on the side surface of the connecting portion 23, into which a plate-shaped locking piece 104i (see Figure 2) is locked. The locking piece 104i is fixed to the support block 104f while locked in the locking groove 23a. This prevents rotation and displacement of the load cell 1.

[0036] Furthermore, the load cell body 2 includes a strain gauge chamber 24 in which the strain gauge 4 is housed. The strain gauge 4 is adhesively fixed to the strain gauge chamber 24. The strain gauge chamber 24 is a hole that is recessed radially in the small diameter portion 21. The strain gauge chamber 24 is recessed in the small diameter portion 21, for example, in the left-right direction D2. In the load cell body 2 of this embodiment, a pair of strain gauge chambers 24 are arranged opposite each other in the left-right direction D2 of one small diameter portion 21. The inside of the strain gauge chamber 24 may be subjected to potting, which will be described later.

[0037] Furthermore, the load cell body 2 may have a counterbore 24a that is radially recessed around the entire circumference of the opening of the strain gauge chamber 24, as shown in Figure 4. In Figures 3 and 4, each strain gauge chamber 24 is shown with an opening facing outwards, but in reality, the opening is closed by a lid (not shown), and this lid is placed in the counterbore 24a.

[0038] Furthermore, the load cell body 2 may include a wiring arrangement section 25 extending from the strain gauge chamber 24 to the housing section 3. The wiring arrangement section 25 is a hole in which the second wiring 7 connecting the strain gauge 4 and the circuit section 5 is arranged. The wiring arrangement section 25 is a hole extending in the front-rear direction D1 of the load cell body 2, and connects adjacent strain gauge chambers 24 in the front-rear direction D1, or the strain gauge chamber 24 to the inside of the housing section 3.

[0039] The housing portion 3 is positioned adjacent to the front-rear end D1 of the load cell body 2. Specifically, the housing portion 3 is positioned adjacent to the connection portion 23 of the load cell body 2. The housing portion 3 is a bottomed cylindrical member positioned coaxially with the load cell body 2 and having an opening 3a. The housing portion 3 may include a cylindrical portion 3b, a bottom portion 3c that closes one end of the cylindrical portion 3b, and a notch 3d formed in the cylindrical portion 3b from a part of the opening 3a toward the bottom portion 3c.

[0040] The cylindrical portion 3b is, for example, cylindrical. The bottom portion 3c is, for example, disc-shaped. The bottom portion 3c has a through hole formed continuously with the wiring arrangement portion 25. The notch 3d is, for example, a rectangular notch.

[0041] The second wiring 7 connects the strain gauge 4 and the circuit section 5 through the wiring arrangement section 25. The second wiring 7 includes an input line 71 for inputting (applying) a predetermined voltage (applied voltage) output from the circuit section 5 to the strain gauge 4, and an output line 72 for transmitting the voltage output from the strain gauge 4 to the circuit section 5 (see Figure 7).

[0042] The length of each second wire 7 may be greater than or equal to the distance from the strain gauge 4 to the opening 3a of the housing 3. This allows for extra length in the second wires 7, making it easier for the worker to perform connection work (soldering, etc.) between the second wires 7 and the circuit section 5 outside the housing 3.

[0043] Each strain gauge 4 detects the resistance change caused by its expansion and contraction in conjunction with the load cell body 2, converts it into a voltage change, and outputs it. Specifically, when a predetermined voltage is applied to the strain gauge 4, it expands and contracts in conjunction with the load cell body 2, causing the voltage output from the strain gauge 4 to change. The voltage output from the strain gauge 4 is an analog signal.

[0044] As shown in Figures 3 and 4, the circuit section 5 may include a first substrate 51 and a second substrate 52 fixed on top of the first substrate 51. The first substrate 51 and the second substrate 52 are fixed in parallel. The first substrate 51 and the second substrate 52 are arranged along the front-rear direction D1. That is, the first substrate 51 and the second substrate 52 are arranged along a direction perpendicular to the bottom 3c of the housing section 3. This makes it easy to house the first substrate 51 and the second substrate 52 into the housing section 3 through the opening 3a.

[0045] As shown in Figure 5, the first substrate 51 and the second substrate 52 are arranged such that, when viewed in the direction of the central axis axis of the housing 3 (in this embodiment, the front-to-back direction D1), the direction D4 perpendicular to the surface of the first substrate 51 and the second substrate 52 is inclined with respect to the direction D5 perpendicular to the outer surface of the cylindrical portion 3b where the notch 3d is formed (in this embodiment, the radial direction of the cylindrical portion 3b). As a result, as shown in Figure 5, even when the first wiring 6 is brought out of the housing 3 in a slack state within the housing 3, the load on the first wiring 6 can be reduced compared to when the direction D4 perpendicular to the surface of the first substrate 51 and the second substrate 52 is parallel to the direction D5 perpendicular to the outer surface of the cylindrical portion 3b where the notch 3d is formed. The reason for leaving the first wire 6 slack inside the housing 3 and bringing it out of the housing 3 is that if the first wire 6 were left straight and not slack inside the housing 3, a pulling force would be directly applied to the circuit section 5 and the soldered part of the first wire 6 when the first wire 6 is pulled. By leaving the first wire 6 slack, this pulling force can be mitigated.

[0046] As shown in Figures 3 and 4, the second substrate 52 is smaller than the first substrate 51. Furthermore, the first substrate 51 and the second substrate 52 are positioned so that their ends on the opening 3a side coincide in the front-to-back direction D1. This creates a stepped portion 53 between the overlapping first substrate 51 and the second substrate 52. The stepped portion 53 is on the surface of the first substrate 51 facing the second substrate 52 and is located on the side of the second substrate 52. A portion of the second wiring 7 may be housed in this stepped portion 53. Note that a portion of the second wiring 7 may be housed in the stepped portion 53 in a coiled state. This allows a portion of the second wiring 7 to be housed in the remaining space of the circuit section 5 (in this embodiment, the stepped portion 53), eliminating the need to provide separate space for the second wiring 7 and thus saving space.

[0047] The first substrate 51 and the second substrate 52 may be fixed in the housing section 3 by potting. Potting is a processing method in which the first substrate 51 and the second substrate 52 are placed in the housing section 3, resin is filled into the housing section 3, and the resin is allowed to solidify to fix the first substrate 51 and the second substrate 52. This allows the first substrate 51 and the second substrate 52 to be removed by scraping out the resin and then repositioned in the housing section 3, even if they are incorrectly fixed in the wrong position.

[0048] As shown in Figure 4, the load cell 1 may include a lid 31 that is detachably provided on the opening 3a of the housing 3, and a fixing member 32 that fixes the lid 31 to the opening 3a. By making the lid 31 detachable from the opening 3a, the first substrate 51 and the second substrate 52 can be easily removed. In addition, the lid 31 can suppress the lifting of the first substrate 51 and the second substrate 52, and can also suppress leakage of the resin during the potting process.

[0049] The fixing member 32 may be a snap ring, for example, as in this embodiment. In this case, a ring groove 3e into which the snap ring is inserted is formed on the inner circumferential surface of the cylindrical portion 3b near the opening 3a of the housing portion 3, as shown in Figures 3 and 4.

[0050] As shown in Figure 7, the circuit unit 5 includes an application unit 5a that applies a predetermined voltage to the strain gauge 4, and a calculation unit 5b that derives the weight applied to the load cell body 2 from the voltage output from the strain gauge 4 and outputs the derived weight as a weight signal.

[0051] The voltage application unit 5a is provided, for example, on the first substrate 51. The voltage application unit 5a applies a voltage to each strain gauge 4 and also applies a voltage to each calculation unit 5b.

[0052] The calculation unit 5b is provided, for example, on the second substrate 52. The second substrate 52 may further include an input unit 5c to which the voltage output from each strain gauge 4 is input, a memory unit 5d for storing the calculation results from the calculation unit 5b, a temperature sensor 5e for detecting the ambient temperature, and an output unit 5f for outputting the weight signal output from the calculation unit 5b to the outside.

[0053] The calculation unit 5b derives the weight applied to the load cell body 2 based on the changes in voltage output from each of the four strain gauges 4, and outputs the derived result as a weight signal. The calculation unit 5b can also correct the derived weight based on the ambient temperature detected by the temperature sensor 5e.

[0054] The memory section 5d is non-volatile memory.

[0055] The output unit 5f outputs the weight derived by the calculation unit 5b to the indicator 106, etc. The output unit 5f converts the weight signal output from the calculation unit 5b into a digital signal and outputs it. The output unit 5f communicates with the indicator 106, etc., for example, via CAN (Controller Area Network).

[0056] The first wiring 6 is a wire that extends from the circuit section 5 (specifically, the application section 5a of the first substrate 51 and the output section 5f of the second substrate 52) to the outside of the housing section 3, and the circuit section 5 is connected to the battery 105 and the indicator 106 by connecting the cable wire 107 (see Figure 6). As shown in Figures 3 and 4, the first wiring 6 extends to the outside of the housing section 3 by passing through the notch 3d of the housing section 3. This makes it easier for the worker to perform the connection work (soldering, etc.) between the first wiring 6 and the circuit section 5 outside of the housing section 3, and then house the circuit section 5 inside the housing section 3 with the first wiring 6 connected. As shown in Figure 4, the first wiring 6 extends to the outside of the housing section 3 by passing through the notch 3d in a direction perpendicular to the strain gauge 4 (in this embodiment, the left-right direction D2).

[0057] The battery 105 supplies power to each load cell 1 (specifically, the circuit unit 5) and the indicator 106 via the cable wire 107.

[0058] The indicator 106 is located in the driver's cab 103a and displays the weight of the load placed on the loading section 101 based on the weight signals output from each load cell 1 (circuit section 5). Furthermore, the indicator 106 may also display the weight applied to each load cell 1, the center of gravity of the load (loading section 101) determined based on the weight applied to each load cell 1, and the like.

[0059] [1] Based on the above, the load cell 1 preferably comprises, as in this embodiment, a load cell body 2 extending in a predetermined direction (in this embodiment, the front-rear direction) D1, which is subjected to deformation when a load is applied in a direction perpendicular to the predetermined direction D1 (in this embodiment, the up-down direction) D3; a bottomed cylindrical housing portion 3 adjacent to the end of the load cell body 2 in the predetermined direction D1 and having an opening 3a; substrates (in this embodiment, a first substrate and a second substrate) 51, 52 housed in the housing portion 3; and a first wiring 6 extending from the substrates 51, 52 to the outside of the housing portion 3. The housing portion 3 comprises a cylindrical portion 3b, a bottom portion 3c that closes one end of the cylindrical portion 3b, and a notch 3d formed in the cylindrical portion 3b from a part of the opening 3a toward the bottom portion 3c, and the first wiring 6 extending to the outside of the housing portion 3 through the notch 3d.

[0060] With this configuration, the housing section 3, which houses the substrates 51 and 52, is positioned adjacent to the load cell body 2, to which the strain gauge 4 is fixed, thus allowing the substrates 51 and 52 to be positioned close to the strain gauge 4.

[0061] [2] Furthermore, in the load cell 1 described in [1] above, it is preferable that, as in this embodiment, it comprises a strain gauge 4 fixed to the load cell body 2 and detecting the strain of the load cell body 2, and a second wiring 7 connecting the strain gauge 4 to the substrates 51 and 52, wherein the length of the second wiring 7 is greater than or equal to the distance from the strain gauge 4 to the opening 3a of the housing 3.

[0062] With this configuration, there is extra length in the second wiring 7, and connection work (soldering, etc.) between the second wiring 7 and the circuit section 5 can be performed outside the housing section 3, making it easier for the worker to perform the work.

[0063] [3] Furthermore, in the load cell 1 described in [2] above, it is preferable that the substrates 51 and 52, as in this embodiment, comprise a first substrate 51 and a second substrate 52 which is fixed on top of the first substrate 51 and is smaller than the first substrate 51, and that a portion of the second wiring 7 is housed in a stepped portion 53 formed by the stacked first substrate 51 and second substrate 52.

[0064] With this configuration, a portion of the second wiring 7 can be housed in the remaining space of the circuit section 5 (in this embodiment, the stepped section 53), eliminating the need to provide separate space for housing the second wiring 7 and thus enabling space saving.

[0065] [4] Furthermore, in any one of the load cells 1 described in [1] to [3] above, it is preferable that the substrates 51 and 52 are arranged in a direction perpendicular to the bottom 3c of the housing 3, as in this embodiment.

[0066] With this configuration, the substrates 51 and 52 can be easily placed inside the housing section 3 through the opening 3a. Furthermore, with this configuration, the substrates 51 and 52 can be easily removed from the housing section 3 through the opening 3a. Moreover, with this configuration, the condition of the substrates 51 and 52 can be easily checked from outside the housing section 3 through the opening 3a.

[0067] [5] Furthermore, in the load cell 1 described in [4] above, it is preferable that, as in this embodiment, when viewed in the direction of the central axis of the housing portion 3, the direction D4 perpendicular to the plate surface of the substrates 51 and 52 is inclined with respect to the direction D5 perpendicular to the outer surface of the cylindrical portion 3b in the portion where the notch 3d is formed.

[0068] With this configuration, even when the first wiring 6 is left slack inside the housing 3 and then brought out of the housing 3, the load on the first wiring 6 can be reduced compared to when the direction D4 perpendicular to the surface of the first substrate 51 and the second substrate 52 is parallel to the direction D5 perpendicular to the outer surface of the cylindrical portion 3b where the notch 3d is formed. Note that when direction D4 is inclined with respect to direction D5, it means that direction D4 is not parallel to direction D5, and also includes the case when direction D4 is perpendicular to direction D5.

[0069] [6] Furthermore, in any one of the load cells 1 described in [1] to [5] above, it is preferable that the substrates 51 and 52 are fixed within the housing section 3 by potting, as in this embodiment.

[0070] With this configuration, even if the circuit boards 51 and 52 are incorrectly fixed in the housing section 3, the resin can be scraped out to remove the circuit boards 51 and 52, and then the circuit boards 51 and 52 can be repositioned.

[0071] [7] Furthermore, in any one of the load cells 1 described in [1] to [6] above, it is preferable that, as in this embodiment, it includes a lid 31 that is detachably provided on the opening 3a of the housing 3, and a fixing member (a snap ring in this embodiment) 32 that fixes the lid 31 to the opening 3a.

[0072] With this configuration, the lid 31 can be attached to and detached from the opening 3a, making it easy to remove the first substrate 51 and the second substrate 52. In addition, the lid 31 can suppress the lifting of the first substrate 51 and the second substrate 52, and can also suppress leakage of the potting resin.

[0073] [8] Furthermore, the weighing vehicle 100 is preferably configured to include, as in this embodiment, a loading section 101 on which loads can be loaded, a vehicle section 102 on which the loading section 101 is mounted, and one of the load cells 1 from [1] to [7] above, which is positioned between the loading section 101 and the vehicle section 102.

[0074] With this configuration, substrates 51 and 52 can be placed near the strain gauge 4.

[0075] It should be noted that the load cell 1 and the vehicle with weighing function 100 are not limited to the configuration of the embodiment described above, nor are they limited to the effects described above. Furthermore, it goes without saying that the load cell 1 and the vehicle with weighing function 100 can be modified in various ways without departing from the spirit of the present invention. For example, one or more of the configurations and methods described below may be arbitrarily selected and adopted in the configurations and methods of the embodiment described above.

[0076] (A) In the load cell 1 according to the above embodiment, the length of the second wiring 7 is greater than or equal to the distance from the strain gauge 4 to the opening 3a of the housing 3. However, the load cell 1 is not limited to this configuration. For example, the length of the second wiring 7 may be shorter than the distance from the strain gauge 4 to the opening 3a of the housing 3, as long as it can connect the strain gauge 4 to the substrates 51 and 52.

[0077] (B) In addition, in the load cell 1 according to the above embodiment, the substrates 51 and 52 comprise a first substrate 51 and a second substrate 52 which is smaller than the first substrate 51 and is fixed on top of the first substrate 51, and a part of the second wiring 7 is housed in a stepped portion 53 formed by the stacked first substrate 51 and second substrate 52. However, the load cell 1 is not limited to this configuration. For example, the first substrate 51 and the second substrate 52 may be the same size, or the second substrate 52 may be larger than the first substrate 51.

[0078] (C) In addition, in the load cell 1 according to the above embodiment, the substrates 51 and 52 are arranged in a direction perpendicular to the bottom 3c of the housing 3. However, the load cell 1 is not limited to this configuration. For example, the substrates 51 and 52 may be arranged along the bottom 3c of the housing 3.

[0079] (D) In ​​addition, in the load cell 1 according to the above embodiment, when viewed in the direction of the central axis of the housing 3, the direction D4 perpendicular to the plate surface of the substrates 51 and 52 is inclined with respect to the direction D5 perpendicular to the outer surface of the cylindrical portion 3b in the portion where the notch 3d is formed. However, the load cell 1 is not limited to this configuration. For example, when viewed in the direction of the central axis of the housing 3, the direction D4 perpendicular to the plate surface of the substrates 51 and 52 is parallel to the direction D5 perpendicular to the outer surface of the cylindrical portion 3b in the portion where the notch 3d is formed.

[0080] (E) In addition, in the load cell 1 according to the above embodiment, the substrates 51 and 52 are fixed within the housing 3 by potting. However, the load cell 1 is not limited to this configuration. For example, the substrates 51 and 52 may be fixed within the housing 3 by adhesive.

[0081] (F) In addition, the load cell 1 according to the above embodiment is configured to include a lid 31 that is detachably provided on the opening 3a of the housing 3, and a snap ring 32 that fixes the lid 31 to the opening 3a. However, the load cell 1 is not limited to this configuration. For example, the fixing member 32 that fixes the lid 31 to the opening 3a may be a bolt or a clip.

[0082] (G) In the load cell 1 according to the above embodiment, the housing section 3 is arranged coaxially with the load cell body 2. However, the load cell 1 is not limited to this configuration. The housing section 3 may also be arranged such that its central axis intersects (for example, perpendicular to) the central axis of the load cell body 2.

[0083] (H) In addition, in the load cell 1 according to the above embodiment, the circuit section 5 is configured to include two substrates (a first substrate 51 and a second substrate 52). However, the load cell 1 is not limited to this configuration. The circuit section 5 may include one substrate, or it may include three or more substrates.

[0084] (I) In the load cell 1 according to the above embodiment, the first substrate 51 and the second substrate 52 are arranged in a stacked state. However, the load cell 1 is not limited to this configuration. The first substrate 51 and the second substrate 52 may be arranged separately.

[0085] (J) If the opening in the strain gauge chamber 24 is covered by a lid, potting may not be performed. Conversely, if potting is performed inside the strain gauge chamber 24, the lid may be omitted.

[0086] (K) In the load cell 1 according to the above embodiment, the load cell body 2 extends in the front-rear direction D1. However, the load cell 1 is not limited to this configuration. The load cell body 2 may also extend in the left-right direction D2, for example. Alternatively, the load cell body 2 may extend in a horizontal direction other than the front-rear direction D1 and the left-right direction D2, for example.

[0087] (L) In addition, the weighing vehicle 100 of the above embodiment is configured as a dump truck. However, the weighing vehicle 100 is not limited to this configuration. The weighing vehicle 100 may be a garbage truck, a tank truck, a freight truck, a mixer truck, a powder and granular material transport vehicle, a cargo bed or tailgate lift of a vehicle with a tailgate lift, a container transport vehicle, a vehicle with a detachable body, a washing and suction vehicle, etc. [Explanation of Symbols]

[0088] 1...Load cell, 2...Load cell body, 3...Housing section, 3a...Opening, 3b...Cylindrical section, 3c...Bottom section, 3d...Notch, 3e...Ring groove, 4...Strain gauge, 5...Circuit section, 5a...Application section, 5b...Calculation section, 5c...Input section, 5d...Memory section, 5e...Temperature sensor, 5f...Output section, 6...First wiring, 7...Second wiring, 21...Small diameter section, 22...Large diameter section, 23...Connection section, 23a...Locking groove, 24...Strain gauge chamber, 24a...Counterbore section, 25...Wiring arrangement section, 31...Lid, 32...Snap ring (fixing member), 51...First circuit board, 52...Second circuit board, 53...Step section, 71...Input wire, 72...Output wire, 100...Vehicle with weighing function, 101...Loading section, 1 01a...Cargo box, 101b...Subdeck frame, 101c...Cargo box body, 101d...Tailgate, 101e...Transmission section, 101f...Through hole for load cell, 102...Vehicle section, 103...Vehicle body, 103a...Driver's cab, 103b...Chassis frame, 104...Oscillating mechanism section, 104a...Main frame, 104b...Deck frame, 104c...Pin, 104d...Dumping device, 104e...Support section, 104f...Support block, 104g...Through hole for load cell, 104h...Mounting plate, 104i...Locking piece, 105...Battery, 106...Indicator, 107...Cable wire, D1...Front / back direction, D2...Left / right direction, D3...Up / down direction

Claims

1. A load cell body extending in a predetermined direction, which is subjected to deformation when a load is applied in a direction perpendicular to the predetermined direction, A bottomed cylindrical housing portion having an opening is adjacent to the end of the load cell body in the predetermined direction, A substrate housed in the aforementioned housing section, It comprises a first wiring extending from the substrate to the outside of the housing, The housing portion comprises a cylindrical portion, a bottom portion that closes one end of the cylindrical portion, and a notch formed in the cylindrical portion extending from a part of the opening toward the bottom portion. The first wiring is a load cell that passes through the notch and extends outside the housing.

2. A strain gauge fixed to the load cell body and used to detect the strain of the load cell body, It comprises a second wiring that connects the strain gauge and the substrate, The load cell according to claim 1, wherein the length of the second wiring is greater than or equal to the distance from the strain gauge to the opening of the housing.

3. The substrate comprises a first substrate and a second substrate which is fixed on top of the first substrate and is smaller than the first substrate. A portion of the second wiring is housed in a stepped portion formed by the stacked first and second substrates, as described in claim 2.

4. The load cell according to any one of claims 1 to 3, wherein the substrate is arranged in a direction perpendicular to the bottom of the housing portion.

5. The load cell according to claim 4, wherein, when viewed in the direction of the central axis of the housing portion, the direction perpendicular to the plate surface of the substrate is inclined with respect to the direction perpendicular to the outer surface of the cylindrical portion of the portion in which the notch is formed.

6. The load cell according to any one of claims 1 to 3, wherein the substrate is fixed in the housing by potting.

7. A load cell according to any one of claims 1 to 3, comprising a lid detachably provided in the opening of the housing, and a fixing member for fixing the lid to the opening.

8. A loading section capable of loading cargo, A vehicle section on which the aforementioned loading section is mounted, A vehicle with a weighing function, comprising a load cell according to any one of claims 1 to 3, disposed between the loading section and the vehicle section.

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