Distortion detection module

Abstract

To provide a strain detection module capable of improving detection accuracy of force acting on a strain generation part of a measuring instrument.SOLUTION: In the strain detection module in which a bridge circuit is provided to make a current flow between four terminals and a plurality of wirings connecting the terminals from the four terminals, a predetermined resistance element is connected in parallel with a first resistance element related to establishment of a balance condition of the bridge circuit, and at least a second resistance element and a predetermined resistance element are connected in series between the wirings extending between the terminals. The second resistance element has an electric resistance smaller than that of the first resistance element as an adjustment of the parallel connection of the first resistance element to the predetermined wiring.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a strain detection module that is attached to a strain-generating part (elastic body) provided in a specified measuring device (such as a load cell or torque converter), and that uses a bridge circuit (hereinafter also referred to as a Wheatstone bridge circuit) to detect changes in resistance value depending on the amount of strain caused by a force (such as a load or torque) acting based on the application to this strain-generating part, thereby enabling the measurement of that force. [Background technology]

[0002] As shown in FIG. 7, the bridge circuit provided in the strain detection module is configured to allow current to circulate between four terminals a to d, four strain gauges Ga to Gd, and multiple wirings connecting these in a square path, and is balanced to satisfy the balance condition of the bridge circuit (the relationship "Ga×Gc=Gb×Gd" shown in the figure) (a so-called Wheatstone bridge circuit), which is known to enable detection to determine a resistance value (amount of strain) proportional to the force acting on the strain-generating part of the measuring instrument.

[0003] The strain gauges Ga to Gd are sensor components in which multiple metal wires extending at an inclination (for example, at least one of +45 degrees or -45 degrees) along the direction of maximum sensitivity are arranged in parallel on each substrate (a base made of a thin electrical insulator), and the ends of the metal wires are folded back and forth in a zigzag pattern to form a continuous resistor (sensing part).

[0004] The above force measurement is made possible by detecting the voltage change corresponding to the amount of strain caused by the force acting on the strain-generating part of the measuring instrument, based on a standard setting process (Wheatstone bridge circuit) that sets the potential difference extracted from the output signal part (±SIG) to zero when electricity is supplied from the applied voltage part (±EXC) shown in Figure 7 when the force acting on the strain-generating part is zero, and then calculating the resistance difference proportional to the amount of strain.

[0005] Here, the Young's modulus (elastic modulus) of the strain-generating part of the measuring instrument changes with temperature, so in some cases, the circuit is configured to include a compensating resistive element (resistor) that makes the potential difference extracted from the output signal part (±SIG) shown in Figure 7 zero at a predetermined temperature, thereby compensating for the temperature characteristics of the strain-generating part (see Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-151596 Summary of the Invention [Problem to be solved by the invention]

[0007] However, due to the influence of various disturbances, such as external interference factors (e.g., centrifugal force, vibration) that accompany the generation of forces acting on the strain-generating part, and physical factors (e.g., installation errors, adhesives, base structure and materials) that accompany attaching the strain detection module to the strain-generating part, even if a circuit design was made that sought to ideally satisfy the balance conditions of the bridge circuit installed in the strain detection module, it was practically difficult to achieve a balance in which the four output values ​​(each resistance measurement) obtained from the detection of each wiring between the four terminals (four strain gauges) were perfectly matched with each other.

[0008] In other words, depending on the environment in which the measuring device is used (the influence of the above-mentioned disturbances), the balance condition of the bridge circuit is inherently induced to collapse, making it difficult to make the potential difference extracted from the output signal section (±SIG) strictly zero, which leads to a decrease in the detection accuracy of the force acting on the strain-generating section of the measuring device.

[0009] In view of the above problems, an object of the present invention is to provide a strain detection module that can improve the detection accuracy of the force acting on the strain-flexing part of a measuring device. [Means for solving the problem]

[0010] In order to achieve the above object, the distortion detection module of the present invention comprises: A strain detection module having four terminals and a plurality of wires connecting the four terminals to allow current to flow between the four terminals, and a bridge circuit that conducts a predetermined resistor between the terminals, The specified wiring extending between these terminals is a first resistor element connected in parallel, which contributes to the balancing condition of a bridge circuit that balances the resistance measurements obtained by using a plurality of the resistors; and the resistor and the second resistor element are at least connected in series at an intermediate portion of the wiring, The second resistor element is The adjustment for connecting the first resistor element in parallel to the predetermined wiring is characterized in that the electrical resistance is set to be smaller than the electrical resistance of the first resistor element.

[0011] In order to achieve the above object, the distortion detection module of the present invention comprises: A strain detection module attached to a strain-flexing part to enable detection in a measuring instrument that detects a force acting on the strain-flexing part and converts the force into an electrical signal, The first resistor element is The electrical resistance (attenuation resistance, resistance value) is determined according to a correction amount obtained by comparing a known detection value obtained as a detection of a loss of balance in the bridge circuit due to a disturbance that occurs when force is applied to the strain-generating part in the measuring instrument (including when attached as described above) with a known reference value that is determined in advance to satisfy the balance condition.

[0012] In order to achieve the above object, the distortion detection module of the present invention comprises: A strain detection module that conducts a predetermined resistor provided on a strain gauge to each of the intermediate points between four terminals in a bridge circuit, The strain gauges mentioned above are a first resistor (sensing part) extending in a first inclination (maximum sensitivity direction A) and formed by folding back and connecting each end of a resistance wire (a plurality of thin metal wires) arranged in parallel; a second resistor (sensing part) extending in a second inclination (maximum sensitivity direction B) and formed by folding back and connecting each end of a resistance wire (a plurality of thin metal wires) arranged in parallel; are configured to be symmetrical, At each intermediate point in the wiring extending between the terminals, either a series combination of two first resistors or a series combination of two second resistors selected for each strain gauge is connected; The device is characterized in that a first resistor element having an electrical resistance corresponding to a positive or negative correction amount (a ± deviation amount from the reference zero point) obtained by comparing a known detection value with a known reference value, the characteristics of which differ depending on whether it is a series combination of a first resistor (maximum sensitivity direction of the first slope) or a second resistor (maximum sensitivity direction of the second slope), is connected in parallel.

[0013] In order to achieve the above object, the distortion detection module of the present invention comprises: The predetermined wiring is: a first wiring extending between predetermined terminals, and a second wiring extending between terminals of a bridge circuit that is not adjacent to the first wiring but is in a first opposing relationship; Alternatively, a second opposing relationship of the bridge circuit different from the first opposing relationship, in which a third wiring and a fourth wiring extend between terminals adjacent to the first wiring or the second wiring, The present invention is characterized in that it is at least one of the above.

[0014] In order to achieve the above object, the distortion detection module of the present invention comprises: Either a series combination of two first resistors or a series combination of two second resistors selected for each strain gauge is connected at each intermediate point of the first wiring and the second wiring, The first and second wirings mentioned above are a first resistance element having a first electrical resistance corresponding to the positive correction amount or the negative correction amount (the characteristic in the maximum sensitivity direction based on the one series combination) is connected in parallel; In addition, a second resistor element having an electric resistance smaller than the electric resistance of the first resistor element is further connected in series between each of the first wiring and second wiring.

[0015] In order to achieve the above object, the distortion detection module of the present invention comprises: At each intermediate point of the third wiring and the fourth wiring, the other of a series combination of two first resistors different from the one of the first resistors or a series combination of two second resistors is connected; The third and fourth wirings mentioned above are a third resistance element having a second electrical resistance corresponding to a positive or negative correction amount (a characteristic in the maximum sensitivity direction based on the series combination of the other resistance) different from the first electrical resistance is connected in parallel; In addition, a fourth resistor element having an electric resistance smaller than the electric resistance of the third resistor element is further connected in series between each of the third wiring and fourth wiring.

[0016] In order to achieve the above object, the distortion detection module of the present invention comprises: a fifth resistor element is further connected in series between one or more predetermined wirings; The fifth resistor element mentioned above is It may also be an electrical resistance related to compensation for the loss of balance in the bridge circuit when the strain-causing part in the measuring device reaches a predetermined temperature. [Effects of the Invention]

[0017] According to the present invention, it is possible to provide a strain detection module that can improve the detection accuracy of a force acting on a strain-flexing part of a measuring device. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a perspective view showing an external appearance of a torque converter according to an embodiment of the present invention; [Figure 2] FIG. 2 is a cross-sectional view of a measurement section of a torque converter according to an embodiment of the present invention. [Figure 3]2 is a cross-sectional view along the line AA of the measurement section of the torque converter according to the embodiment of the present invention. FIG [Figure 4] 1 is a circuit diagram including a strain gauge of a torque transducer according to an embodiment of the present invention. [Figure 5] FIG. 2 is a plan view of a strain detection module according to an embodiment of the present invention. [Figure 6] FIG. 10 is a circuit diagram showing a configuration of a Wheatstone bridge circuit according to another embodiment. [Figure 7] FIG. 1 is a circuit diagram showing the configuration of a conventional Wheatstone bridge circuit. DETAILED DESCRIPTION OF THE INVENTION

[0019] A detailed description will be given below based on a torque transducer 1, which is an example of a measuring instrument equipped with a strain detection module 20 of the present invention.

[0020] The supplementary contents in parentheses in this specification are examples of the present invention, and the present invention is not limited to these supplementary contents. In addition, the same or equivalent elements are given the same reference numerals, and redundant explanations may be omitted.

[0021] FIG. 1 is a perspective view showing the external appearance of a torque converter 1 according to an embodiment of the present invention, and shows a torque measuring section 13 and an electrical component box 9. As shown in FIG.

[0022] The torque measurement unit 13 includes a strain-generating part 2, flange parts 3a and 3b, strain gauges G1 to G4 (not shown in Fig. 1) installed inside these parts, and a circuit board 12. A power supply part 7 and a rotation speed detection part 8 are provided on the top surface of the electrical equipment box 9.

[0023] The torque measuring unit 13 and the electrical equipment box 9 are configured separately, and the torque converter 1 is used by installing both of them at a predetermined position and interval. The torque converter 1 detects minute changes in electrical resistance corresponding to the amount of strain generated by the force (torsion) acting on the strain-flexing unit 2 using strain gauges G1 to G4 (a Wheatstone bridge circuit, described later), and converts this into an electrical signal for output, thereby enabling torque measurement.

[0024] The flange portion 3a is made of a ring-shaped metal with high rigidity that is not easily deformed. The flange portion 3a has a plurality of screw holes arranged at equal angular intervals in the circumferential direction, and is connected to the driving member on the driving side with bolts.

[0025] The flange portion 3b is also made of a ring-shaped metal with high rigidity that is not easily deformed. The flange portion 3b has a plurality of screw holes arranged at equal angular intervals in the circumferential direction, and is connected to the subordinate load member with bolts.

[0026] Gear 4 is a spur gear provided on the flange portion 3a side. Gear 4 protrudes radially from the outer periphery of flange portion 3a and is located midway between flange portions 3a and 3b in the direction of the rotation axis.

[0027] The strain-flexing part 2 is located between the flange parts 3a and 3b in the central axial direction and is concentric with the flange parts 3a and 3b. The strain-flexing part 2 has a hollow cylindrical shape, and the flange parts 3a and 3b at both ends of the strain-flexing part 2 are formed as an integral member.

[0028] The diameter of the outer cylindrical surface of the strain-flexing part 2 is smaller than the diameter of the outer periphery of the flange parts 3a and 3b, and the thickness thereof is also formed to be relatively small. The strain-flexing part 2 is made of, for example, carbon steel, and its Poisson's ratio is 0.27 to 0.3.

[0029] Rotational speed detection unit 8 uses gear 4 to detect the rotational speed and direction of torque measurement unit 13. Rotational speed detection unit 8 has two magnetic resistance elements arranged at a predetermined distance from gear 4 on the circumference close to the tip circle of rotating gear 4, and detects the change in magnetic force caused by the tip of the gear 4 passing between these magnetic resistance elements to detect the rotational speed and direction.

[0030] Furthermore, rotation speed detection unit 8 is provided so as to be covered with a shielding member (not shown) made of a conductive material so as to block noise generated from power supply unit .

[0031] Antenna 14 is used to wirelessly transmit a signal indicating the torque value measured by torque measuring unit 13. Antenna 14 is, for example, an annular printed circuit board with conductor wires printed on it, and is fitted onto the outer cylindrical surface of flange 3a and fixed to the side of gear 4.

[0032] The wire drawn from the antenna 14 is led into the interior of the torque measuring unit 13 through a hole provided in the outer cylindrical surface of the flange portion 3a, and is connected to a circuit board 12 fixed inside the torque measuring unit 13.

[0033] The power receiving coil 5 is a coil wound around the outer periphery of the flange portion 3b, and is used to receive power from the power supply portion 7. A wire drawn from the power receiving coil 5 is led into the inside of the torque measuring portion 13 through a hole provided in the cylindrical surface of the flange portion 3b, and is connected to a circuit board 12 fixed inside the torque measuring portion 13.

[0034] A power transmitting coil is housed in the power supply unit 7. This power transmitting coil is coupled to the power receiving coil 5 at a predetermined distance to form a rotary transformer. This rotary transformer configuration allows power to be transmitted from the electrical component box 9 to the torque measuring unit 13 in a contactless manner.

[0035] The lid 6 is provided to protect the components arranged inside the torque measuring unit 13 from wind force and dust generated by high-speed rotation.

[0036] The electrical component box 9 houses a board including a non-contact power transmission circuit, a torque output circuit, a rotation detection circuit, and a power supply circuit.

[0037] The non-contact power transmission circuit then transmits power to the torque measurement unit 13 via the power supply unit 7 in a non-contact manner.

[0038] The torque output circuit also receives a digital torque signal from the antenna 14 of the torque measuring unit 13, demodulates it, and outputs a torque value.

[0039] The rotation detection circuit also detects the rotation speed and rotation direction of the torque measurement unit 13 from the rotation speed detection unit 8 and outputs the results.

[0040] The power supply circuit also converts externally supplied power and supplies it to each circuit.

[0041] Fig. 2 is a cross-sectional view taken along a vertical plane including the central axis AX of the measurement part of the torque transducer 1 according to the embodiment of the present invention. Fig. 3 is a cross-sectional view taken along line AA in Fig. 2.

[0042] The strain-flexing part 2 is located between the flange parts 3a and 3b in the axial direction, and the flange parts 3a and 3b are coaxial. The strain-flexing part 2 has a hollow cylindrical shape, and the flange parts 3a and 3b at both ends of the strain-flexing part 2 are formed as an integral member.

[0043] The diameter of the outer cylindrical surface of the strain-flexing part 2 shown in Figure 2 is smaller than the diameter of the outer periphery of the flange parts 3a and 3b, and the thickness of the outer cylindrical surface is also relatively small. In addition, the outer circumferential surface 2a of the strain-flexing part 2 is provided with a groove-shaped thin-walled part 10 extending in the circumferential direction.

[0044] 2, a circuit board 12 is disposed and fixed in the hollow portion of the torque measuring part 13. Wiring drawn from a Wheatstone bridge circuit provided in a strain detection module 20 attached to the inner peripheral surface of the strain-flexing part 2, which will be described later, is connected to this circuit board 12.

[0045] FIG. 4 schematically shows the circuit mounted on the circuit board 12, the strain gauges G1 to G4 mounted in the Wheatstone bridge circuit, and the relationship between them.

[0046] The circuit board 12 shown in FIG. 4 includes an amplifier circuit 15, an analog / digital conversion circuit 16, an arithmetic circuit 17, a modulation circuit 18, and a transmission circuit 19.

[0047] The strain detection module 20 described above uses four strain gauges G1 to G4 electrically connected on a film-like substrate body 30 to implement a Wheatstone bridge circuit that forms a square wiring pattern configuration (forming a path for flowing current between four terminals) as shown in FIG. 4.

[0048] The circuit board 12 is connected to the wire drawn from the receiving coil 5 so that it can receive the transmitted power, and a rectifier circuit rectifies this power, enabling it to be supplied to the amplifier circuit 15, analog / digital conversion circuit 16, arithmetic circuit 17, modulation circuit 18, transmission circuit 19, and distortion detection module 20 (Wheatstone bridge circuit).

[0049] The amplifier circuit 15 shown in FIG. 4 amplifies the analog signal output from the distortion detection module 20 connected to the circuit board 12.

[0050] Also, the analog / digital conversion circuit 16 converts the analog signal into a digital signal.

[0051] The arithmetic circuit 17 also performs an arithmetic operation on this digital signal to generate an electric signal representing the torque value, that is, a torque signal.

[0052] The arithmetic circuit 17 is composed of a CPU (Central Processing Unit), RAM (Random Access Memory), rewritable ROM (Read Only Memory), input / output units, and the like.

[0053] The modulation circuit 18 also modulates the digital torque signal to generate a modulated signal.

[0054] The transmitting circuit 19 also transmits the modulated signal onto a carrier wave to the receiving circuit in the electrical equipment box 9 .

[0055] The strain detection module 20 attached to the inner peripheral surface of the strain-generating part 2 shown in Figure 2 is able to calculate the torque acting on the strain-generating part 2 by utilizing predetermined (sensing elements) resistors (first resistor, second resistor) provided in the strain gauges G1 to G4 of the bridge circuit mounted on the substrate main body 30 to detect (measure resistance) changes in resistance value corresponding to the amount of strain caused by the force acting on the strain-generating part 2.

[0056] As shown in FIG. 4, the bridge circuit of this embodiment is configured as a Wheatstone bridge circuit, which includes four terminals T1 to T4, four strain gauges G1 to G4, and a plurality of wires connecting these to form a rectangular path, allowing current to circulate through wiring patterns S1 to S4 extending between the four terminals.

[0057] The four strain gauges G1 to G4 are all arranged to have the same configuration (sensing elements), and the first resistors g1T to g4T and the second resistors g1C to g4C are connected in series at the middle of the wiring patterns S1 to S4, respectively, so that they can cooperate with each other.

[0058] [Detailed configuration of strain gauge G1] An enlarged plan view of the strain gauge G1 according to this embodiment is shown in Fig. 2. The coordinate system (X, Y) in Fig. 2 is defined as shown in the figure.

[0059] As shown in FIG. 2, the strain gauge G1 has a first resistor g1T, a second resistor g1C, conductor portions 41a to 41c, and node portions 42a to 42c patterned on a base film substrate 40 while ensuring insulation from the surroundings.

[0060] In this embodiment, the substrate 40 is, for example, a dielectric polyimide film. The first resistor g1T, the second resistor g1C, the conductor portions 41a to 41c, and the nodes 42a to 42c are made of metal, for example, an alloy of copper and nickel.

[0061] The film-like substrate 40 according to this embodiment is made of the same material as the substrate body 30 in the strain detection module 20 (for example, integrally molded), but may be made of a different material.

[0062] The first resistor g1T and the second resistor g1C are formed as a folded pattern (sensing element) (zigzag sensing part) in which the end tab portions 43 of adjacent wires are folded back and connected to form a connecting region in a plurality of wires (ultra-thin metal wires) arranged in parallel (parallel arrangement) for detecting the amount of strain generated based on the force applied to the strain-generating part 2. The width of each of the plurality of wires and the spacing between them are made relatively small.

[0063] The first resistor g1T is disposed on one side (-X) of the substrate 40, and the second resistor g1C is disposed on the other side (+X) of the substrate 40 with the center line AC as its axis.

[0064] The conductor portions 41a to 41c shown in FIG. 2 are signal wiring portions electrically connected to the first resistor g1T and the second resistor g1C, and have a line width thick enough that distortion is not detected.

[0065] Specifically, the conductor portion 41a is a signal wiring portion electrically connected to one end of the first resistor g1T, the conductor portion 41b is a signal wiring portion electrically connected to one end of the second resistor g1C, and the conductor portion 41c is a signal wiring portion electrically connected to both the other end of the first resistor g1T and the other end of the second resistor g1C.

[0066] 2 is an extension of the conductor portion 41a and is disposed on the other (+X) side of the second resistor g1C. The node portion 42a is electrically connected to wiring mounted on the substrate main body 30.

[0067] The node 42b is an extension of the conductor portion 41b and is disposed on one side (-X) of the first resistor g1T. The node 42b is electrically connected to a wiring mounted on the substrate body 30.

[0068] A node 42c is disposed between the first resistor g1T and the second resistor g1C via a conductor 41c. The node 42c is electrically connected to a terminal T1 mounted on the substrate body 30.

[0069] Each of the multiple wires arranged in parallel at fine intervals as components of the first resistor g1T shown in Figure 2 is arranged to extend with a narrow line width that allows it to detect distortion with maximum sensitivity (first tilt) in direction E (negative Θ angle) in the XY coordinate system.

[0070] The length of the first resistor g1T in the direction E of strain detection is formed as a series of folded patterns (zigzag-shaped sensing parts) that gradually increase from one end side, the conductor part 41b, and gradually decrease toward the other end side, the conductor part 41c.

[0071] In addition, each of the multiple wires arranged in parallel at fine intervals as components of the second resistor g1C is arranged to extend with a narrow line width that allows maximum sensitivity (second tilt) in direction F (plus angle Θ) in the XY coordinate system to detect distortion.

[0072] The length of the second resistor g1C in the direction F of strain detection is formed as a series of folded patterns (zigzag-shaped sensing parts) that gradually increase from one end side, the conductor part 41a, and gradually decrease toward the other end side, the conductor part 41c.

[0073] In the strain gauge G1 according to this embodiment, the directions of maximum sensitivity for detecting strain in the first resistor g1T and the second resistor g1C intersect at a predetermined angle (±Θ), and are arranged symmetrically with respect to the center line AC in the Y-axis direction, making it a shear-type biaxial strain-sensitive resistor.

[0074] In this embodiment, the first resistor g1T, the second resistor g1C, and the upper surfaces of the conductor portions 41a to 41c (or the strain detection module 20) are covered with a protective layer (not shown). This protective layer is formed by applying a liquid or by adhering a film, and has a thickness of about several μm to 30 μm.

[0075] By providing the protective layer, it is possible to prevent mechanical damage to the first resistor g1T and the second resistor g1C, etc., and also to protect them from moisture and the like.

[0076] Note that the nodes 42a to 42c in this embodiment may not be provided with the protective layer, and may be connected to lead wires or the like by soldering, etc. The protective layer may be formed of an insulating resin such as polyimide resin, epoxy resin, PEEK resin, PET resin, or PPS resin.

[0077] [Detailed configuration of the distortion detection module 20] FIG. 5 is a plan view of the strain detection module 20 attached to the inner circumferential surface of the strain-flexing part 2 of the torque converter 1 shown in FIG.

[0078] The strain detection module 20 is rectangular in shape with one long, narrow side on which four strain gauges G1 to G4 are arranged (integrally molded) at predetermined equal intervals, and is based on a film-like substrate body 30 that is sufficiently flexible so that it can be attached (bent) to match the perimeter of the inner surface of the strain-generating part 2.

[0079] The substrate body 30 according to this embodiment may be made of a thin insulating material (plastic film) and may be a flexible printed circuit (FPC) that can be bent.

[0080] The substrate main body 30 has a bridge circuit formed thereon in which the first resistors g1T to g4T or the second resistors g1C to g4C patterned on each strain gauge G1 to G4 (on the base material 40) are electrically connected by wire bonding to four terminals T1 to T4 and wiring patterns S1 to S4 extending between each of the four terminals.

[0081] Also, a circuit pattern is formed in which first resistive elements (resistors) Ra4 and Ra2 or third resistive elements (resistors) Ra1 and Ra3, which are connected in parallel to the wiring patterns S1 to S4, are electrically connected by wire bonding.

[0082] In addition, a circuit pattern is formed in the middle of each of the wiring patterns S1 to S4, in which second resistive elements (resistors) Rc4 and Rc2, fourth resistive elements (resistors) Rc1 and Rc3, and fifth resistive elements (resistors) Zs+ and Zs- are connected in series.

[0083] The strain gauge G1 and strain gauge G3 shown in Figure 5 are actually (see Figure 3) positioned opposite each other at an angle of 180 degrees across the central axis AX of the strain-flexing part 2 to which the strain detection module 20 is attached.

[0084] Furthermore, the strain gauges G2 and G4 shown in FIG. 5 are actually positioned opposite each other at an angle of 180 degrees across the central axis AX of the strain-flexing part 2 (see FIG. 2 or 3).

[0085] As can be seen from Figures 5 and 2, first resistors g1T to g4T in the direction of maximum sensitivity forming a first inclination in direction E (a negative Θ angle) and second resistors g1C to g4C in the direction of maximum sensitivity forming a second inclination in direction F (a positive Θ angle) are patterned on the substrate 40 of each strain gauge G1 to G4.

[0086] In this embodiment, when a torsional moment is generated in the strain-generating part 2 in response to the rotation of the torque transducer 1 connected to the object to be measured with a load, one of the first resistors g1T to g4T (or second resistors g1C to g4C) stretches, increasing the resistance value, and the other second resistor g1C to g4C (or first resistor g1T to g4T) contracts, decreasing the resistance value. This characteristic (resistance measurement) is detected based on processing on the circuit board 12.

[0087] The bridge circuit provided in the distortion detection module 20 of this embodiment is a so-called Wheatstone bridge circuit, and based on the above characteristics (first resistors g1T to g4T or second resistors g1C to g4C), a digital signal (change in resistance value) related to the detected voltage can be output as a result of current variations occurring.

[0088] Then, the digital signal is demodulated based on processing by a torque output circuit provided in the electrical component box 9, so that the torque generated in the strain-flexing part 2 can be measured (torque value output).

[0089] Here, in the torque transducer 1, due to physical factors (mounting errors, adhesives, disturbances related to the base structure and material, etc.) that occur when attaching the strain detection module 20 to the strain-generating part 2, it becomes difficult to arrange the strain gauges G1 to G4 in a strictly balanced relationship on the inner surface (circumferential length) of the strain-generating part 2, which makes it easy for quality variations to occur.

[0090] Furthermore, external interference factors (e.g., disturbances related to centrifugal force, vibration, etc.) generated by the high-speed rotation (application) of the strain-generating part 2 of the torque converter 1 cause the strain gauges G1 to G4 to be displaced into a more inappropriate position, resulting in a lack of consistent stability.

[0091] Therefore, the conventional torque transducer 1 rotates at high speed by the strain-flexing part 2 to which the strain gauges G1 to G4 are attached, which is an unbalanced arrangement that is not ideal for measuring the resistance of the strain amount. As a result, the equilibrium condition of the bridge circuit (bridge balance of the Wheatstone bridge circuit) that balances the resistance measurements obtained using the strain gauges G1 to G4 of the strain detection module 20 is lost, causing a considerable error (zero point shift) in the calculation process on the circuit board 12.

[0092] Therefore, in the conventional torque converter 1, it was necessary to improve the accuracy of torque measurement by adding a control procedure that involves rotating the strain-flexing part 2 in advance, comparing (difference) a value (known detected value) related to the test output (e.g., converted into %FS) obtained using an unadjusted Wheatstone bridge circuit with an ideal output value (known reference value) that is determined in advance by a circuit design that satisfies the balance conditions of the bridge circuit, deriving in advance the deviation amount A (error) from the zero point that serves as the balance reference, calculating a correction value A according to the deviation amount A from the zero point, registering this correction value A in the memory unit of the conventional torque converter 1, and enabling specified correction processing to be performed based on this registration.

[0093] In contrast to this, in this embodiment, as shown in Figures 4 and 5, first resistance elements Ra4 and Ra2 are connected in parallel to the wiring pattern S1 and the wiring pattern S3, respectively, and an attempt is made to add a damping resistance (corrective electrical resistance) that can compensate for the unequal state (deviation amount A from the above-mentioned zero point) to achieve an ideal (bridge balance) by having the first resistance elements Ra4 and Ra2 participate in establishing the equilibrium condition of the bridge circuit that collapses depending on the usage environment of the torque converter 1 (the influence of the above-mentioned external disturbance).

[0094] Furthermore, through further development and verification, it has become clear that torque measurement can be achieved that does not require (or almost does not require) the addition of the above-mentioned correction processing by connecting second resistance elements Rc4 and Rc2, which have electrical resistance smaller than the electrical resistance of the first resistance elements Ra4 and Ra2, in series with the first resistors g1T to g4T at each intermediate point between wiring patterns S1 and S3, based on the individual combined resistance between each terminal obtained by connecting first resistance elements Ra4 and Ra2 in parallel to each wiring pattern S1 and wiring pattern S3, respectively, as an adjustment to the delicate balance conditions of the bridge circuit, which can be disrupted even by the additional influence of the above-mentioned parallel connection.

[0095] In addition, in this embodiment, as shown in Figures 4 and 5, third resistance elements Ra1 and Ra3 are connected in parallel to the wiring pattern S2 and the wiring pattern S4, respectively, and an attempt is made to add a damping resistance (corrective electrical resistance) that can compensate for the unequal state to an ideal (bridge balance) by having the third resistance elements Ra1 and Ra3 participate in establishing the equilibrium condition of the bridge circuit that collapses depending on the usage environment of the torque converter 1 (the influence of the above-mentioned external disturbances).

[0096] Furthermore, through further development and verification, it has become clear that torque measurement can be achieved that does not require (or almost does not require) the addition of the above-mentioned correction processing by connecting fourth resistance elements Rc1 and Rc3, which have electrical resistance smaller than that of the first resistance elements Ra4 and Ra2, in series with the second resistance elements g1C to g4C at each intermediate point between wiring patterns S1 and S3, based on the individual combined resistance between each terminal obtained by connecting third resistance elements Ra1 and Ra3 in parallel to wiring patterns S2 and S4, respectively, as an adjustment to the delicate balance conditions of the bridge circuit, which can be disrupted even by the additional influence of the above-mentioned parallel connection.

[0097] Therefore, the strain detection module 20 according to this embodiment can improve the detection accuracy of the force acting on the strain-flexing part 2 of the torque converter 1.

[0098] The fifth resistor element Zs- in the wiring pattern S3 (or wiring pattern S1) shown in Figure 4 is the fifth resistor element Zs- connected in series with the second resistor element Rc2 based on the above characteristics (first resistors g1T to g4T or second resistors g1C to g4C), and is a negative compensation resistor element that contributes to making the potential difference extracted from the output signal section (±SIG) based on the electrical supply from the applied voltage section (±EXC) shown in Figure 4 zero at a predetermined temperature, as compensation for the change in Young's modulus in the strain-generating section 2 due to temperature.

[0099] As a variant, based on the above characteristics of the wiring pattern S3 (or the wiring pattern S1), the fifth resistor element Zs+ connected in series with the second resistor element Rc2 may be configured to be a positive compensation resistor element that contributes to making the resistor element zero at a predetermined temperature.

[0100] Furthermore, the fifth resistor element Zs+ in the wiring pattern S2 (or wiring pattern S4) shown in FIG. 4 is a fifth resistor element Zs+ that is connected in series with the fourth resistor element Rc1 based on the above characteristics (first resistors g1T to g4T or second resistors g1C to g4C), and is a positive compensation resistor element that contributes to making the potential difference extracted from the output signal section (±SIG) based on the electrical supply from the applied voltage section (±EXC) shown in FIG. 4 zero at a predetermined temperature, as compensation for the change in Young's modulus in the strain-generating section 2 due to temperature.

[0101] As a variant, based on the above characteristics of the wiring pattern S3 (or the wiring pattern S1), the fifth resistor element Zs- connected in series with the fourth resistor element Rc1 may be configured to be a negative compensation resistor element that contributes to making the resistor element zero at a predetermined temperature.

[0102] [Detailed configuration of wiring patterns S1 to S4] As shown in FIG. 4, the wiring pattern S1 (first wiring) connects the first resistor g1T of the strain gauge G1, the first resistor g2T of the strain gauge G2, and the second resistor Rc4 in series between the terminals T1-T4.

[0103] The wiring pattern S1 shown in FIG. 4 is formed as a connecting wiring pattern that connects the first resistor element Ra4 in parallel between the terminals T1-T4.

[0104] The magnitude of the electrical resistance of the first resistor element Ra4 is determined by previously rotating the strain-generating part 2 and comparing the test output value obtained from the first resistors g1T and g2T connected in series at the middle of the wiring pattern S1 with the ideal output value that satisfies the balance conditions of the bridge circuit to determine the amount of deviation from the zero point that serves as the balance reference, and then determining the value (corrective electrical resistance) of the attenuation resistance (balance that contributes to satisfying the balance conditions of the bridge circuit) that is added to compensate for the amount of deviation from the zero point (necessary correction amount).

[0105] The deviation amount from the zero point in the wiring pattern S1 is considered to be a phenomenon that indicates either a positive deviation amount from the zero point when the first resistors g1T, g2T expand and become larger due to the generation of a torsional moment in the strain-generating portion 2, based on the characteristics of the common maximum sensitivity direction (first inclined folding pattern) of the first resistors g1T, g2T connected in series in the middle of the wiring pattern S1, or a negative deviation amount from the zero point when the first resistors g1T, g2T contract and become smaller due to the generation of a torsional moment in the strain-generating portion 2.

[0106] The second resistor element Rc4 is set to have an electrical resistance (adjusted resistance) smaller than the electrical resistance of the first resistor element Ra4, based on the combined resistance when the first resistor element Ra4 is connected in parallel in the wiring pattern S1 (first resistors g1T, g2T + first resistor element Ra4), and is adapted to adjust for satisfying the balance condition of the bridge circuit, which can be disrupted by the additional effect of the parallel connection.

[0107] As shown in FIG. 4, the wiring pattern S3 (second wiring) is disposed opposite the wiring pattern S1 in the diagram of the Wheatstone bridge circuit (first opposing relationship of the bridge circuit).

[0108] The first resistor g3T of the strain gauge G3, the first resistor g4T of the strain gauge G4, the second resistor Rc2, and the fifth resistor Zs+ are connected in series between the terminals T2 and T3.

[0109] In addition, the wiring pattern S3 shown in Figure 4 is formed as a connecting wiring pattern that connects in parallel the first resistor element Ra2, which is determined to have the same (or approximately the same) electrical resistance as the first resistor element Ra4 between the terminals T2 and T3.

[0110] The deviation amount from the above-mentioned zero point in the wiring pattern S3 is considered to be a phenomenon that indicates either a positive deviation amount from the above-mentioned zero point when the first resistors g3T and g4T expand and become larger due to the generation of a torsional moment in the strain-flexing portion 2, based on the characteristics of the common maximum sensitivity direction (first inclined folding pattern) of the first resistors g1T and g2T connected in series in the middle of the wiring pattern S3 and the first resistors g3T and g4T connected in series in the middle of the wiring pattern S3, or a negative deviation amount from the above-mentioned zero point when the first resistors g3T and g4T contract and become smaller due to the generation of a torsional moment in the strain-flexing portion 2.

[0111] The second resistor element Rc2 is set to have an electrical resistance (adjusted resistance) smaller than the electrical resistance of the first resistor element Ra2, based on the combined resistance when the first resistor element Ra2 is connected in parallel in the wiring pattern S3 (first resistors g3T, g4T + first resistor element Ra2 + fifth resistor element Zs+), and is adapted to adjust for satisfying the balance condition of the bridge circuit, which can be disrupted by the additional influence of the parallel connection.

[0112] Therefore, the deviation amount from the zero point in the wiring pattern S1 and the wiring pattern S3 becomes either the deviation amount in the positive direction or the deviation amount in the negative direction, and a damping resistance (corrective electrical resistance) is added that can compensate for the balance (deviation amount from the zero point) that contributes to satisfying the equilibrium condition of the bridge circuit that is disrupted based on the usage environment of the torque converter 1 (the influence of the above-mentioned external disturbances).

[0113] As shown in FIG. 4, the wiring pattern S2 (third wiring) is disposed adjacent to the wiring pattern S1 or the wiring pattern S3 in the diagram of the Wheatstone bridge circuit.

[0114] The second resistor g1C of the strain gauge G1, the second resistor g4C of the strain gauge G4, the fourth resistor Rc1, and the fifth resistor Zs- are connected in series between the terminals T1 and T2.

[0115] The wiring pattern S2 shown in FIG. 4 is formed as a connecting wiring pattern that connects the third resistor element Ra1 in parallel between the terminals T1 and T2.

[0116] The magnitude of the electrical resistance of the third resistor element Ra1 is determined as the value (corrective electrical resistance) of the attenuation resistance (balance that contributes to satisfying the balance conditions of the bridge circuit) to be added as compensation for the deviation from the zero point, which is the balance reference, based on a comparison of the value related to the test output obtained from the second resistors g1C and g4C connected in series in the middle of the wiring pattern S2 by rotating the strain-generating part 2 in advance with the ideal output value that satisfies the balance conditions of the bridge circuit.

[0117] In addition, the deviation amount from the above-mentioned zero point in the wiring pattern S2 is considered to be a phenomenon that indicates either a positive deviation amount from the above-mentioned zero point when the second resistors g1C and g4 expand and become larger due to the generation of a torsional moment in the strain-generating portion 2, based on the characteristics of the common maximum sensitivity direction (second inclined folding pattern) of the second resistors g1C and g4C connected in series in the middle of the wiring pattern S2, or a negative deviation amount from the above-mentioned zero point when the second resistors g1C and g4 contract and become smaller due to the generation of a torsional moment in the strain-generating portion 2.

[0118] The fourth resistor element Rc1 is designed to have an electrical resistance (adjustment resistance) smaller than that of the third resistor element Ra1, which is determined based on the combined resistance when the third resistor element Ra1 is connected in parallel in the wiring pattern S2 (second resistors g1C, g4C + third resistor element Ra1 + fifth resistor element Zs-), and is adapted to adjust for satisfying the balance condition of the bridge circuit, which can be disrupted by the additional effect of the parallel connection.

[0119] As shown in FIG. 4, the wiring pattern S4 (fourth wiring) is disposed opposite the wiring pattern S2 in the diagram of the Wheatstone bridge circuit (second opposing relationship in the bridge circuit).

[0120] The second resistor g2C of the strain gauge G2, the second resistor g3C of the strain gauge G3, and the fourth resistor Rc3 are connected in series between the terminals T3 and T4.

[0121] In addition, the wiring pattern S4 shown in Figure 4 is formed as a pattern of connecting wiring that connects the third resistor element Ra3 in parallel, with the electrical resistance between terminals T3-T4 being determined to be the same (or approximately the same) as the electrical resistance of the third resistor element Ra3.

[0122] In addition, the deviation amount from the above-mentioned zero point in wiring pattern S4 is considered to be a phenomenon that indicates either a positive deviation amount from the above-mentioned zero point when a torsional moment is generated in strain-flexing portion 2, causing second resistors g2C and g3C to expand and become larger, based on the characteristics of the common maximum sensitivity direction (second inclined folding pattern) of second resistors g1C and g4C connected in series in the middle of wiring pattern S2 and second resistors g2C and g3C connected in series in the middle of wiring pattern S2, or a negative deviation amount from the above-mentioned zero point when a torsional moment is generated in strain-flexing portion 2, causing second resistors g2C and g3C to contract and become smaller.

[0123] The fourth resistor element Rc3 is set to have an electrical resistance (adjustment resistance) smaller than the electrical resistance of the third resistor element Ra3, which is adapted to adjust for satisfying the balance condition of the bridge circuit, which can be disrupted by the additional effect of the parallel connection, based on the combined resistance when the third resistor element Ra3 is connected in parallel in the wiring pattern S4 (second resistors g2C, g3C + third resistor element Ra3).

[0124] Therefore, the deviation amount from the zero point in the wiring pattern S2 and the wiring pattern S4 becomes either the deviation amount in the positive direction or the deviation amount in the negative direction, and a damping resistance (corrective electrical resistance) is added that can compensate for the balance (deviation amount from the zero point) that contributes to satisfying the equilibrium condition of the bridge circuit that is disrupted based on the usage environment of the torque converter 1 (the influence of the above-mentioned external disturbances).

[0125] As a modified example, only when the deviation amount from the above-mentioned zero point in the wiring pattern S1 and the wiring pattern S3 is a negative deviation amount (or either a positive deviation amount, or a predetermined deviation amount such as negative deviation amount > positive deviation amount), the wiring pattern may be formed such that first resistor elements Ra4 and Ra2 are connected in parallel to each of the wiring pattern S1 and the wiring pattern S3, and second resistor elements Rc4 and Rc2 are connected in series to each of the wiring pattern S1 and the wiring pattern S3.

[0126] That is, when the deviation amount from the above-mentioned zero point in the wiring pattern S1 and the wiring pattern S3 is a deviation amount in the positive direction (or either a deviation amount in the negative direction, or a predetermined deviation amount such as a deviation amount in the negative direction < a deviation amount in the positive direction), the wiring pattern may be formed so that the first resistor elements Ra4 and Ra2 are not connected in parallel to the wiring pattern S1 and the wiring pattern S3, respectively, and the second resistor elements Rc4 and Rc2 are not connected in series to the wiring pattern S1 and the wiring pattern S3, respectively.

[0127] As another modified example, only when the deviation amounts from the above-mentioned zero point in the wiring pattern S2 and the wiring pattern S4 are positive deviation amounts (or either negative deviation amounts, or a predetermined deviation amount such as positive deviation amount > negative deviation amount), the wiring pattern may be formed such that third resistor elements Ra1, Ra3 are connected in parallel to each of the wiring pattern S2 and the wiring pattern S4, and fourth resistor elements Rc1, Rc3 are connected in series to each of the wiring pattern S2 and the wiring pattern S4.

[0128] That is, when the deviation amount from the above-mentioned zero point in the wiring pattern S2 and the wiring pattern S4 is a negative deviation amount (or either one of the positive deviation amounts, or a predetermined deviation amount such as positive deviation amount < negative deviation amount), the wiring patterns may be formed such that the third resistor elements Ra1 and Ra3 are not connected in parallel to the wiring pattern S2 and the wiring pattern S4, respectively, and the fourth resistor elements Rc1 and Rc3 are not connected in series to the wiring pattern S2 and the wiring pattern S4, respectively.

[0129] As another modification, as shown in FIG. 6, the first resistor element Ra4 may be configured such that the first resistor element Ra4′ and the first resistor element Ra4′ are connected in parallel, and the combined resistance (Ra4′+Ra4′) may be added in parallel as a damping resistance between the terminals (T1-T4) of the wiring pattern S1 in order to more delicately balance the equilibrium conditions of the bridge circuit, which may be disrupted by a predetermined disturbance.

[0130] As another modification, as shown in FIG. 6, the first resistor element Ra2 may be configured such that the first resistor element Ra2′ and the first resistor element Ra2′ are connected in parallel, and the combined resistance (Ra2′+Ra2′) may be added in parallel as a damping resistance between the terminals (T2-T3) of the wiring pattern S3 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a predetermined disturbance.

[0131] As another modification, as shown in FIG. 6, the second resistor element Rc4 may be configured such that the second resistor element Rc4′ and the second resistor element Rc4′ are connected in parallel, and the combined resistance (Rc4′+Rc4′) may be added in series as an adjustment resistance between the terminals (T1-T4) of the wiring pattern S1 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a certain disturbance.

[0132] As another modification, as shown in FIG. 6, the second resistor element Rc2 may be configured such that the second resistor element Rc2′ and the second resistor element Rc2′ are connected in parallel, and the combined resistance (Rc2′+Rc2′) may be added in series as an adjustment resistance between the terminals (T2-T3) of the wiring pattern S3 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a predetermined disturbance.

[0133] As another modification, as shown in FIG. 6, the third resistor element Ra1 may be configured such that the third resistor element Ra1′ and the third resistor element Ra1′ are connected in parallel, and the combined resistance (Ra1′+Ra1′) may be added in parallel as a damping resistance between the terminals (T1-T2) of the wiring pattern S2 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a predetermined disturbance.

[0134] As another modification, as shown in FIG. 6, the third resistor element Ra3 may be configured such that the third resistor element Ra3′ and the third resistor element Ra3′ are connected in parallel, and the combined resistance (Ra3′+Ra3′) may be added in parallel as a damping resistance between the terminals (T2-T3) of the wiring pattern S3 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a predetermined disturbance.

[0135] As another modification, as shown in FIG. 6, the fourth resistor element Rc1 may be configured such that the fourth resistor element Rc1′ and the fourth resistor element Rc1′ are connected in parallel, and the combined resistance (Rc1′+Rc1′) may be added in series as an adjustment resistance between the terminals (T1-T2) of the wiring pattern S2 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a predetermined disturbance.

[0136] As another modification, as shown in FIG. 6, the fourth resistor element Rc3 may be configured such that the fourth resistor element Rc3′ and the fourth resistor element Rc3′ are connected in parallel, and the combined resistance (Rc3′+Rc3′) may be added in series as an adjustment resistance between the terminals (T3-T4) of the wiring pattern S4 in order to more delicately balance the equilibrium conditions of the Wheatstone bridge circuit, which may be disrupted by a predetermined disturbance.

[0137] In addition, in this embodiment, the strain detection module 20 is configured to form a Wheatstone bridge circuit based on the substrate main body 30, but in another embodiment, the strain detection module may be configured by forming the Wheatstone bridge circuit based on directly attaching the strain gauges G1 to G4 to the inner surface of the strain-generating part 2.

[0138] Furthermore, in this embodiment, when distortion occurs at an angle of approximately 45 degrees, the torque related to the component in the direction of the rotation axis (moment of force) acting on the strain-generating part 2 may be set so that the maximum sensitivity direction for detecting minute changes in electrical resistance (distortion) by the first resistor and second resistor (sensing part) is ±45 degrees.

[0139] The above-described embodiment has been described as a case where the measuring device according to the present invention is applied to a torque transducer 1. However, the present invention is not necessarily limited to the scope of the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0140] Furthermore, the materials, shapes, dimensions, and numbers of the components in the above-described embodiments are merely examples, and it goes without saying that any configuration may be adopted as long as the effects of the present invention can be exhibited. Therefore, the terms "symmetrical" and "equally spaced" used in the present invention do not mean symmetrical or equally spaced in the strict sense, and slight deviations that do not deviate from the scope of the present invention are within the permissible scope of the present invention. [Industrial Applicability]

[0141] As an example of application of the present invention, it is possible to apply it to other measuring instruments (such as load cells) that make it possible to detect force by using a bridge circuit (or Wheatstone bridge circuit) that includes strain gauges G. [Explanation of symbols]

[0142] 1: Torque transducer 2: Strain part 2a: Outer surface 2b: Inner peripheral surface 3a, 3b: Flange part 4: Gears 5: Receiving coil 6: Lid 7: Power supply unit 8: Rotation speed detection section 9: Electrical equipment box 10a~10d: Thin wall part 12: Circuit board 13: Torque measurement section 14: Antenna 15: Amplification circuit 16: Analog / digital conversion circuit 17: Arithmetic circuit 18: Modulation circuit 19: Transmitting circuit 20: Distortion detection module 30: Board body 40: Base material 41a~41c: Conductor part 42a~42c: Node part 43: End tab part G, G1 to G8: Strain gauge g1T~g4T: First resistor g1C~g4C: 2nd resistor body T1~T4: Terminals S1 to S4: Wiring patterns Ra4, Ra2: First resistor element Rc4, Rc2: Second resistor element Ra1, Ra3: Third resistor element Rc1, Rc3: Fourth resistor element Zs+, Zs-: 5th resistor element

Claims

1. A strain detection module having four terminals and a plurality of wires connecting the four terminals to allow current to flow between the four terminals, and a bridge circuit that conducts a predetermined resistor between the terminals, The predetermined wiring extending between the terminals is a first resistance element that contributes to the balance condition of the bridge circuit for balancing resistance measurements obtained by using a plurality of the resistors is connected in parallel; and the resistor and the second resistor element are at least connected in series at an intermediate portion of the wiring, The second resistance element is A strain detection module, characterized in that, as an adjustment for connecting the first resistor element in parallel to the wiring, the electrical resistance is set to be smaller than the electrical resistance of the first resistor element.

2. 2. A strain detection module according to claim 1, which is attached to a strain-flexing part to enable detection of a force acting on the strain-flexing part in a measuring instrument that detects the force acting on the strain-flexing part and converts the force into an electrical signal, The first resistor element is A strain detection module characterized in that the electrical resistance is determined according to a correction amount obtained by comparing a known detection value obtained as a detection of a loss of balance in the bridge circuit due to a disturbance that occurs when force is applied to the strain-generating part with a known reference value that is determined in advance to satisfy the balance condition.

3. 3. The strain detection module according to claim 2, wherein the resistors provided in the strain gauge are electrically connected to the intermediate points between the four terminals of the bridge circuit, The strain gauge is a first resistor extending at a first inclination and formed by folding back and connecting each end of a resistance wire arranged in parallel; a second resistor extending at a second inclination and formed by folding back and connecting the ends of the parallel-arranged resistor wires; are configured to be symmetrical, At each intermediate point of the wiring extending between the terminals, either a series combination of two of the first resistors selected for each strain gauge or a series combination of two of the second resistors is connected; A distortion detection module characterized in that the first resistor element has an electrical resistance corresponding to a positive correction amount or a negative correction amount obtained by comparing the detection value, which has different characteristics depending on whether it is a series combination of the first resistor or the second resistor, with the reference value, and is connected in parallel.

4. 4. The distortion detection module of claim 3, The predetermined wiring is a first wiring extending between predetermined terminals, and a second wiring extending between terminals of the bridge circuit that are not adjacent to the first wiring but are in a first opposing relationship; Alternatively, a second opposing relationship of the bridge circuit different from the first opposing relationship, in which a third wiring and a fourth wiring extend between terminals adjacent to the first wiring or the second wiring, A distortion detection module characterized by being at least one of the above.

5. 5. The distortion detection module of claim 4, a series combination of two of the first resistors selected for each strain gauge or a series combination of two of the second resistors selected for each strain gauge is connected at each intermediate point of the first wiring and the second wiring; Each of the first wiring and the second wiring is the first resistance elements of the first electrical resistance corresponding to the positive correction amount or the negative correction amount are connected in parallel, and a second resistive element having an electrical resistance smaller than that of the first resistive element is further connected in series between each of the first wiring and the second wiring.

6. 6. The distortion detection module of claim 5, the other of a series combination of two of the first resistors different from the one of the first resistors or a series combination of two of the second resistors is connected at each intermediate point of the third wiring and the fourth wiring; Each of the third wiring and the fourth wiring is a third resistor element having a second electrical resistance corresponding to a correction amount that is different from the first electrical resistance and is either positive or negative, and is connected in parallel; and a fourth resistive element having an electrical resistance smaller than that of the third resistive element is further connected in series between each of the third wiring and the fourth wiring.

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