JP4837940B2 - Rotary component force measuring device - Google Patents

Description

  The present invention is a rotary type that measures six component forces of forces Fx, Fy, Fz applied in the x, y, and z axis directions of a Cartesian coordinate system and rotational torques (moments) Mx, My, Mz acting around these axes. The present invention relates to a shaft torque measuring device.

  Conventionally, multi-component force detectors as disclosed in Patent Documents 1 and 2 are known as detectors capable of measuring multi-component force in shaft torque.

  The multi-component force detectors described in Patent Documents 1 and 2 measure the amount of torsion that occurs between the fixed side and the measurement side connected to the drive shaft, and the detector itself does not rotate. A fixed side flange, a measuring side flange facing the fixed side flange, four flat beams extending between the fixed side and the measuring side flange, and affixed to both ends and front and back surfaces of each beam, respectively. A first group of strain gauges and a second group of strain gauges affixed to the center of each beam. The strain gauges are appropriately selected and bridged to selectively detect force. It is characterized by that.

  Moreover, as a conventional torque detector, there was a torque detector as disclosed in Patent Document 3. The torque detector described in Patent Document 2 is connected in the middle of the torque transmission shaft from the engine, and the detector itself is also configured to rotate. The first plate member and the second plate member And a web member that connects the first and second plate members, and a plurality of strain gauges are mounted at selected positions in a selected pattern.

However, the multi-component force detector disclosed in Patent Documents 1 and 2 described above has a technical problem described below.
JP-A-5-256710 JP-A-6-265423 Special table 2003-518240 gazette

  That is, in the multiple force detectors described in Patent Documents 1 and 2, since strain gauges are selected from two groups and bridge connection is made, the strain gauges constituting one bridge circuit span a plurality of sensing units. In this case, the wiring for the connection becomes longer, which causes a component error detection error.

  Further, in the detectors of Patent Documents 1 and 2, the strain gauge detection signal attached to the sensing unit is converted to a component force value by a bridge circuit and then transmitted to the signal processing unit. Since each component is added with an error based on the strain gauge characteristics across a plurality of sensing parts, it is very difficult to obtain the correct component force.

  Furthermore, in the torque detector described in Patent Document 3, since the strain gauge of each sensitive part also detects strains other than in the torque transmission axis direction, it becomes an error, and accurate torque can be measured. could not.

  The present invention has been made in view of such conventional problems, and the object of the present invention is to reduce strain gauge detection errors and to accurately and accurately obtain a component force. An object of the present invention is to provide a possible rotary type component force measuring device.

In order to achieve the above-described object, the present invention uses six component forces of forces Fx, Fy, Fz applied in the axial direction of the orthogonal coordinate system (x, y, z) and torques Mx, My, Mz acting around these axes. In the rotary type component force measuring device to measure, when the rotational driving force is input from one end side, it is arranged between the first and second torque transmission shafts to which the rotational driving force is transmitted. comprising a component force detector for detecting the associated distortion, the component force detector has a sensitive beam portion having a plurality of thin portions are attached so as to correspond to the thin portion, the bridge circuit of four resistance elements A plurality of orthogonal shear type strain gauges to be formed, and the output signal from the bridge circuit is divided according to a timing signal obtained from a rotation angle detection signal of a rotation detector provided in the component force detector. By an electronic circuit located inside the force detector The signal is converted to digital signal by an AD converter, sent to a signal processing circuit, and the signal processing circuit corrects the output signal from each bridge circuit transmitted by correction information stored in advance to perform coordinate conversion. A rotary component force measuring device that calculates the six component forces (Fx, Fy, Fz and the working torques Mx, My, Mz) by performing the correction, and the correction information differs for each of the sensitive beam portions. The information includes primary correction for deformation or high-order correction incorporating rotational deformation according to rotation of the rotation detector.

  According to the rotary component force measuring apparatus configured as described above, since the output signal is taken out for each thin part (sensitive part), the independence of detection for each sensitive part, non-sensitivity between different sensitive parts. Since the coherence is maintained and transmitted to the signal processing circuit in this state, accurate correction in accordance with the distortion gauge characteristics for each output signal and different deformations for each sensitive part can be easily performed with the signal processing circuit, The accuracy of component force calculation is improved.

  The orthogonal shear type strain gauge has a thin portion adjacent in the circumferential direction, the center axis of which coincides with the axis of the component force detector, and the center axis of 45 degrees with respect to the axis of the component force detector. Inclined ones can be arranged alternately.

The sensitive beam portion may be formed in a cylindrical shape, and a plurality of concave portions may be formed on the outer side surface, and the thin portion may be formed on the back side thereof.

  The detection signal detected by the bridge circuit is digitized by an AD converter, and the digitized output signal is converted into a non-contact data transmission method such as electromagnetic coupling, optical data transmission, or wireless transmission, or slip ring. In the contact data transmission system such as by the above, the signal can be transmitted to the signal processing circuit arranged outside the component force detector.

  The correction information may be information including primary correction or high-order correction incorporating rotational deformation according to the rotation of the rotation detector.

  In the stationary state, the signal processing circuit applies a known six component force from the outside for each rotation angle of the torque transmission shaft, and based on the conversion matrix obtained by measuring the bridge signal at that time, the output signal Can be converted into the 6 component force.

  By obtaining such a conversion matrix in advance, conversion from a plurality of output signals to 6 component forces is performed quickly, which contributes to speeding up of signal processing. In addition, according to this configuration, information about the component force applied to the torque transmission shaft and the rotation angle can be obtained. Therefore, an engine performance evaluation test using an engine bench or the like, torque measurement during acceleration / deceleration in an actual vehicle, and AT Used for various applications such as car gear shift control.

  According to the rotational component force measuring apparatus of the present invention, on the torque transmission shaft side, the output signal is sampled according to the timing signal obtained for each sensitive part, and the detection independence for each sensitive part, different perceptions With the incoherence between the parts maintained, the output signal is corrected according to the characteristics of the strain gauge for each sensitive part, and the coordinates are converted to 6 component forces, so the 6 component forces are highly accurate. Is realized. In addition, since the bridge circuit is configured for each sensor unit, the wiring can be shortened and signal errors associated with the wiring can be reduced.

In addition, by transmitting the signal of each sensor unit as it is to the signal processing circuit, the data is corrected using the high-speed calculation function in the signal processing circuit, and the coordinate conversion associated with the sensor unit structure is used. By obtaining the value, correction can be made for each sensitive unit, and multiple types can be obtained simply by changing the number of data transmission signals and changing the calculation method of the signal processing circuit according to the number, structure, and arrangement of the sensitive units. The rotational component force measuring device can be provided.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.

  1 to 11 show a first embodiment of a rotary component force measuring apparatus according to the present invention. FIG. 1 shows an application example when the measuring device 10 of the present invention is incorporated in an engine characteristic measuring device.

  The engine characteristic measuring apparatus shown in the figure includes an engine 2 and a dynamometer 3 mounted on the bench 1 so as to face each other, and a shaft torque meter 4 is coupled to the crankshaft of the engine 2.

  The measuring device 10 of the present invention is interposed between a first torque transmission shaft 5 connected to the crankshaft of the engine and a second torque transmission shaft 6 connected to the rotation shaft of the dynamometer 3, A rotational force is input from either the engine 2 or the dynamometer 3.

  1 is a drive control unit of the engine 2, and 8 is a drive control unit of the dynamometer 3. Reference numeral 9 denotes a central control unit that manages the control units 7 and 8. Reference numeral 11 receives a transmission signal from the central control unit 9 and applies predetermined processing to each control unit 7 and 8. This is a signal processing unit to be transmitted. Reference numeral 12 denotes a monitor display unit for signals sent from the signal processing unit 11.

  In the case of the present embodiment, the measuring device 10 includes a component force detector 20 and a measuring unit 30. The component force detector 20 has a sensitive beam portion 21 and a pair of mounting flanges 22 fixed to both ends thereof.

  As shown in FIG. 2, the component force detector 20 has a mounting flange 22 in contact with flanges 5a and 6a fixed to the ends of the first and second torque transmission shafts 5 and 6, respectively. Is interposed between the first and second torque transmission shafts 5 and 6.

  Details of the component force detector 20 are shown in FIGS. In the component force detector 20 shown in these drawings, a sensitive beam portion 21 is disposed between a pair of disk-shaped mounting flanges 22. In this embodiment, the sensitive beam portion 21 is substantially hollow. It is formed in a cylindrical shape.

  On the outer peripheral surface of the cylindrical sensing beam portion 21, rectangular concave portions 23 are provided at equal intervals along the circumferential direction. By forming the concave portions 23, the back side becomes a thin portion 24. ing.

  In the case of the present embodiment, eight concave portions 23 are provided at equal angular intervals along the circumferential direction, and as a result, eight thin portions 24 are also formed at equal angular intervals along the circumferential direction. Orthogonal shear strain gauges A to H are respectively attached to the back side of each thin portion 24.

  In the rotary component force measuring device 10 of this embodiment, the component force detector 20 is formed of a highly rigid material such as duralumin in order to measure six component forces applied to the torque transmission shaft 5 that transmits the drive from the engine 2. ing. In addition, the shape for attaching to the torque transmission shafts 5 and 6 may be any shape as long as it can be connected to the torque transmission shafts 5 and 6 and does not necessarily have an annular shape.

  5 and 6 is a rotation angle detector of the component force detector 20. In this embodiment, the detector 25 includes a photo interrupter 25a and a light shielding plate 25b. The light shielding plate 25 b is formed in a ring shape and is fixed to the outer periphery of the mounting flange 22.

  When the detector 20 rotates, the light shielding plate 25b rotates on the central axis of the photo interrupter 25a, and a hole 25c formed through the light shielding plate 25b is formed in the light interrupting plate 25b. When it comes to the center, light is transmitted between the interrupters 25a and an output signal is sent out.

  The output signal transmission interval corresponds to the perforation intervals of a large number of holes 25 c formed through the light shielding plate 25 b and the rotational speed of the component force detector 20. 6 is a substrate on which elements such as an IC constituting an electric circuit of a first signal processing circuit 31 of the measuring unit 30 and a data collecting unit 32, which will be described later, are mounted. In the case of the example, a plurality of substrates 26 are supported by a holder 27 and installed in a through hole provided in the center of the component force detector 20.

The orthogonal shear strain gauges A to H detect the strain of the thin portion 24 when a rotational force is applied to the sensitive beam portion 21, and the detailed structure thereof is shown in FIG. The orthogonal shear strain gauges A to H shown in the figure include four resistance elements A1, A2, A3, and A4. The resistive element A1, A2, A3, A4 are formed on a flexible substrate, as shown in FIG. 8, the eight-bridge circuit _B 1 .about.B ₈ is formed.

In the case of a present Example, orthogonal shear strain gauge AH is affixed on the back side of the thin part 24 adjacent to the circumferential direction with two different forms. That is, in the case of the present embodiment, the gage center axis C ₀ shown in FIG. 7 matches the axis of the component force detector 20 (A, C, E, G) and the center axis C ₀ is The components (B, D, F, and H) inclined by 45 degrees with respect to the axis of the component force detector 20 are alternately arranged, and the arrangement is shown in a developed view in FIG. .

In the bridge circuits B _{1 to} B ₈ configured as described above, the strain gauges A, C, E, and G are axial directions of an orthogonal coordinate (x, y, z) system centered on the axis of the component force detector 20. The force Fx, Fy applied to the shaft and the torque Mz acting around the axis are detected, and the strain gauges B, D, F, H detect the force Fz applied in the axial direction and the torque Mx, My acting around the shaft. It will be.

  In this embodiment, a strain gauge with four resistance elements is used, but a strain gauge with three, two, or one element may be used. The strain gauge may be attached not only to the inner surface side of the annular sensing beam portion 21 but also to the outer surface side.

  Details of the measuring unit 30 are shown in FIG. The measurement unit 30 shown in the figure is fixed at a position separated from the first signal processing circuit 31 and the data collection unit 32 mounted on the component force detection unit 20 side which is the rotation side, and the component force detection unit 20 side. And a second signal processing circuit 33 provided on the side (for example, a data collection room, a laboratory, a control room, a computer installation room, etc.).

The first signal processing circuit 31 detects rotation of output signals from the _eight bridge circuits B _{1 to} B ₈ formed by the strain gauges A to H attached to the eight thin portions (sensitive portions) 24. Sampling is performed according to the timing signal obtained from the unit 25.

The first signal processing circuit 31 has a data collection unit 32. The data collection unit 32, in response to a timing signal obtained from the rotation angle detector 25, and the AD converter 32a to AD conversion by sampling the output signal from the bridge circuit _B 1 .about.B _8, and a control unit 32b It is included.

To illustrate a more specific operation of the AD converter 32a, a timing signal generated at each rotation angle (for example, 0.5 degree, 1 degree, etc.) is input from the angle detection unit 25 to the AD converter 32a. AD converters 32a, in response to a timing signal obtained from the rotation angle detector 25 samples the output signal from the bridge circuit B ₁ .about.B ₈ as input data, the digital output a total of eight output signal To do.

  The data control unit 32 b is means for controlling the AD converter 32 a and the angle detection unit 25, and classifying and transmitting the output of the AD converter 32 a for each angle detected by the angle detection unit 25.

The first signal processing circuit 31 sends the output signal sent from the data control unit 32b to the data receiving unit 33a of the second signal processing circuit 33 in accordance with the timing signal obtained from the rotation angle detector 25. It has a sending part 31a. Further, the first signal processing circuit 31 includes a coil 31b and a power receiving unit 31c. The power receiving unit 31c receives the received power from each circuit of the data collection unit 32 and the bridge circuits B _{1 to} B. ₈ is distributed and supplied.

  The second signal processing circuit 33 receives the output signal sampled by the first signal processing circuit 31, and the characteristics of the strain gauges A to H for each sensitive part (thin part 24), different sensitive parts (thin part). 24) are individually corrected based on the interference characteristics of the strain gauges A to H, and 6 component forces are calculated for each rotation angle. The data receiving unit 33a, the coil 33b, the power supply unit 33c, and the signal processing unit 33d.

  In the present embodiment, the transmission of the output signal from the first signal processing circuit 31 to the second signal processing circuit 33 and the transfer of power between the coil 31b and the coil 33b are performed in a non-contact manner. At this time, it is desirable that the transmission path change due to the rotation of the digitized output signal, and the electromagnetic coupling, optical data transmission, wireless transmission, and the like be less affected by errors caused by generated electromagnetic noise.

  In the case of the present embodiment, in addition to the non-contact method, transmission by a contact method using a slip ring or the like may be performed. According to the contact type transmission, existing facilities can be utilized.

  Further, the eight digitized output signals may be transmitted as serial data by direct ASK modulation, or may be transmitted by FSK and PSK modulation as 8-channel multiplexed signals. In addition to serial transmission, parallel transmission may be used. Such data modulation may be performed by the data control unit 32c.

  The signal processing unit 33d is means for obtaining six component forces in the orthogonal coordinate system from a total of eight output signals received from the receiving unit 33a. An example of a detailed configuration of the signal processing unit 33d is shown in FIG. The signal processing unit 33d shown in the figure includes a data demodulation circuit 33e, a signal correction circuit 33f, and a coordinate conversion circuit 33g.

  The data demodulating circuit 33e converts the modulated output signal (in this embodiment, one 8ch multiplexed signal) into a total of eight output signals (A, B, C, D, E, F, G). , H)).

  The signal correction circuit 33f is a means for correcting the output signal based on correction information (correction coefficient) for each angular position of the rotation angle detector 25 stored in advance. In this case, the correction information is obtained by, for example, reading the output signal at the rotation angle 25 when a known output signal is given as a load, and comparing these signals to obtain a correction coefficient representing the correlation between them in advance. It can be stored in a memory or the like.

  In this case, the output signal is input to the signal correction circuit 33f while having the characteristics of the strain gauges A to H for each sensitive part and the interference characteristics (errors) of the strain gauges A to H between different sensitive parts. Therefore, correct correction is performed in accordance with the characteristics of the strain gauges A to H for each output signal and different deformations for each sensitive part, and the subsequent calculation of the component force is performed with high accuracy. For the correction, only linear linear correction is sufficient, and no advanced correction is particularly required.

  In order to reduce the calculation error of the component force, the coefficient of the correction information is adjusted so that each output signal is closest to the theoretical value, or the n-th order term and the product of each term of each output signal are calculated. Correction may be performed in addition to the correction term. At that time, each correction term may be calculated as a correction matrix. Still further, high-order correction incorporating rotational deformation according to the rotation of the rotation angle detector 25 may be performed.

  As described above, the strain gauges A to H are output for each output signal in a state in which the detection independence for each sensitive part and the incoherence between different sensitive parts are maintained before the calculated force, not after the calculated force. Therefore, the correction calculation is easily performed, the validity of the correction is increased, and a correct and highly accurate component force is required.

  The coordinate conversion circuit 33g is a means for performing coordinate conversion of the demodulated total of eight output signals into six component forces of the rotation coordinate system (orthogonal coordinate system x, y, z) for each rotation angle. In this embodiment, the conversion is performed by a matrix operation represented by the following equation.

Here, Fx to Mz are forces Fx, Fy, Fz applied in the x, y, z axis directions of the orthogonal coordinate system of the torque transmission axis, and six component forces of torques Mx, My, Mz acting around these axes, A ˜H are output signals of the _eight bridge circuits B _{1 to} B ₈ , and K _{11 to} K ₆₈ are transformation matrices (matrix for transformation).

This transformation matrix is a component force detector 20 to be used in advance, in a stationary state, for each rotation angle (for example, 1 degree) of the torque transmission shaft, from the outside of the torque transmission shaft, a known 6 component force, for example, In addition to the dynamometer 3, the output signals A to H of the bridge circuits B _{1 to} B ₈ at that time are measured and their correlation is obtained, and the obtained conversion matrix is stored as one of the correction information. And so on. Note that the transformation matrix in this embodiment is as follows.

  By obtaining the conversion matrix in advance in this way, the conversion from the eight output signals to the six component forces is performed quickly, which contributes to speeding up the signal processing.

  The rotary component force measuring device 10 described above has the following merits as compared with a conventionally used device. In other words, conventionally, the difference or sum of the output signals of the bridge circuit is calculated at the portion corresponding to the first signal processing circuit 31, and 6 components are obtained here, and the portion corresponding to the second signal processing circuit 33 is calculated. In the portion corresponding to the second signal processing circuit 33, the error factor is corrected.

  However, in the bridge circuit of the conventional configuration, the wiring straddles a plurality of sensing parts, and the length of the wiring not only causes a component error detection error, but each component of the component force includes a plurality of receiving components. Since an error based on the strain gauge characteristics of the sensing part is added and 6 component forces are calculated in the rotating part, how to correct it by the signal processing part arranged outside the rotating part for each sensitive part It was very difficult to separate into distortion components, and it was impossible to correct different deformations for each sensitive part, and the correct component force could not be obtained.

  In addition, each component of the component force is embedded with an error component generated at the output signal stage of the bridge circuit. Therefore, after obtaining the component force, the characteristics of the strain gauges of the individual sensing parts are different. It is meaningless to perform correction according to the interference characteristics of the strain gauge between the sensing parts, and it is difficult to perform high-level correction.

  On the other hand, in the rotary type component force measuring apparatus 10 of the present embodiment, the inconvenience is eliminated because the component force is calculated by the second signal processing circuit 33. That is, in the rotary component force measuring device 10 of the present embodiment, the first signal processing circuit 31 provided on the rotation side samples the output signal for each sensing unit and for each rotation angle, and calculates the component force. Instead, the signal is sent from the sending unit 31a to the second signal processing circuit 33 and received by the receiving unit 33a of the second signal processing circuit 33 provided outside the rotation side. Then, the signal processing unit 33d The output signal is separated and 6 component forces are calculated. For this reason, the detection independence of each sensitive part and the non-interference between different sensitive parts are maintained. After correcting the output signal, coordinates are converted to 6 component forces for each rotation angle.

Therefore, the correction for the different deformation for each sensitive part is easily performed, and the high accuracy of 6 component force is realized. In addition, since the bridge circuits B _{1 to} B ₈ are configured for each sensing unit, the wiring is short, and signal errors associated with the wiring are reduced.

  Each time the number of the recesses 23 of the sensitive beam portion 21 increases, the number of output signals separated increases, so that the independence and non-interference between the output signals increase, and the six-component force becomes highly accurate. Since the accuracy of the correction of the output signal is realized, the number of the sensing parts and the number of output signals is not necessarily eight.

  Moreover, in the measuring apparatus 10 of a present Example, the number of the recessed parts 23 of the sensitive beam part 21 does not necessarily need to be eight pieces, and if it is three or more, you may change with 4-7, 9 or more.

  FIG. 12 shows a second embodiment of the rotary type component force measuring apparatus according to the present invention, and the same or corresponding parts as those in the first embodiment are denoted by common reference numerals and the description thereof is omitted. Only the characteristic points will be described below.

  This figure is a plan view showing another example of the component force detector 20a. The detector 20a has a sensitive beam portion 21a and a mounting flange 22a. The sensitive beam portion 21a has a hollow cylindrical shape. In the outer peripheral surface, five recesses 23a are provided at equiangular intervals.

  A thin portion 24a is formed on the back side of the recess 23a, and a total of ten orthogonal shear strain gauges S1 to S10 are attached to the inner surface side of the thin portion 24a. The strain gauges S1 to S10 are disposed on the inner surface side of the thin portion 24a and adjacent portions thereof. The interval between the recesses 23a is equally divided at an angle with respect to the center of 2π / 5, that is, every 72 degrees.

Also in this embodiment, strain gauges S1~S10 the center axis C ₀ gauge shown in FIG. 7, and those in a form consistent with the axial component force detector 20, the central axis C ₀ component force Those having an inclination of 45 degrees with respect to the axis of the detector 20 are alternately arranged.

  Also in the case of the present embodiment, the measurement unit 30 has the same configuration as that shown in FIG. 10, and the six component forces of the orthogonal coordinate system are expressed as follows from a total of ten output signals received by the data reception unit 33a. It is calculated | required by the coordinate transformation system shown.

  Even in this embodiment, the signal correction circuit 33e shown in FIG. 11 does not correct the output signal based on the correction information (correction coefficient) for each angular position of the rotation angle detector 25 stored in advance. This is performed in the same manner as in the first embodiment.

  In order to reduce the calculation error of the component force, the coefficient of the correction information is adjusted so that each output signal is closest to the theoretical value, or the n-th order term and the product of each term of each output signal are calculated. Correction may be performed in addition to the correction term. At this time, the correction terms may be collectively calculated as a correction matrix. Further, as in the above-described embodiment, higher-order correction incorporating rotational deformation according to the rotation of the rotation angle detector 25 may be performed. In the second embodiment configured as described above, the same effects as those in the first embodiment can be obtained.

  The information about the component force and rotation angle of the actual rotation coordinate system obtained by the rotary component force measuring device 10a of the present invention is obtained by analyzing the engine torque behavior during engine acceleration and deceleration, Used for misfire and knock detection.

  In the above-described embodiment, a hollow cylindrical shape is exemplified as the component force detector. However, the implementation of the present invention is not limited to this, for example, a disk-shaped one or a polygonal shape. The shape may be a disk or cylinder.

  The rotary component force measuring device according to the present invention can measure the component force with high accuracy, and can be effectively used for measuring engine characteristics such as torque of an internal combustion engine, for example.

It is side surface explanatory drawing which shows an example of the use condition of the rotary type | mold component force measuring apparatus concerning this invention. It is a perspective view of the attachment state of the component force measuring apparatus shown in FIG. It is a front view of the component force detector of the component force measuring apparatus shown in FIG. It is a side view of the component force detector of the component force measuring apparatus shown in FIG. FIG. 4 is a sectional view taken along line AA in FIG. It is the BB sectional view taken on the line of FIG. It is a top view of the strain gauge used for the component force detector of the component force measuring apparatus shown in FIG. It is explanatory drawing of the bridge circuit formed with the strain gauge shown in FIG. It is an expanded view of the sticking position of the strain gauge shown in FIG. It is a block diagram of the measurement part of the component force measuring apparatus shown in FIG. It is detailed explanatory drawing of the signal processing part shown in FIG. It is principal part explanatory drawing which shows 2nd Example of the measuring device concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Rotary type component force measuring device 5 ... 1st torque transmission shaft 6 ... 2nd torque transmission shaft 20 ... Component force detection part 21 ... Sensitive beam part 22 ... Mounting flange 23 ... Recessed part 24 ... Thin part 25 ... Rotation Angle detection unit 30 ... measurement unit 31 ... first signal processing circuit 32 ... data collection unit 33 ... second signal processing circuit

Claims (5)

In a rotary component force measuring device that measures six component forces of forces Fx, Fy, Fz applied in the axial direction of the orthogonal coordinate system (x, y, z) and torques Mx, My, Mz acting around these axes,
A component force detector that is disposed between the first and second torque transmission shafts to which the rotational driving force is transmitted, and detects distortion related to the six component forces when the rotational driving force is input from one end side. With
The component force detector includes a sensing beam portion having a plurality of thin portions ;
A plurality of orthogonal shear type strain gauges attached to correspond to the thin portion and forming a bridge circuit with four resistance elements;
The output signal from the bridge circuit is sampled by an electronic circuit disposed inside the component force detector according to a timing signal obtained from a rotation angle detection signal of a rotation detector provided in the component force detector. , Digitized by AD converter and sent to signal processing circuit,
The signal processing circuit corrects the transmitted output signal from each bridge circuit with correction information stored in advance, and performs coordinate conversion to thereby convert the six component forces (Fx, Fy, Fz and working torque). mx, My, a rotary component force measuring device for calculating a Mz),
The correction information is information including primary correction for different deformation for each of the sensing beam portions or higher-order correction incorporating rotational deformation according to rotation of the rotation detector. Force measuring device. The orthogonal shear type strain gauge has a thin portion adjacent in the circumferential direction, the center axis of which coincides with the axis of the component force detector, and the center axis of 45 degrees with respect to the axis of the component force detector. The rotary component force measuring device according to claim 1, wherein the inclined components are alternately arranged. 3. The rotational component force according to claim 1, wherein the sensing beam portion is formed in a cylindrical shape, and a plurality of concave portions are formed on an outer surface thereof, and the thin portion is formed on a back surface side thereof. Mold measuring device. The detection signal detected by the bridge circuit is digitized by an AD converter, and the digitized output signal is converted into a non-contact data transmission method such as electromagnetic coupling, optical data transmission, or wireless transmission, or slip ring. 4. The rotational component force according to claim 1, wherein the rotational force is transmitted to the signal processing circuit arranged outside the component force detector by a contact data transmission method using, for example, a contact data transmission method. Measuring device. In the stationary state, the signal processing circuit applies a known six component force from the outside for each rotation angle of the torque transmission shaft, and based on the conversion matrix obtained by measuring the bridge signal at that time, the output signal The rotary component force measuring device according to any one of claims 1 to 4, wherein the force component is converted into the six component forces.

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