JP2008064660A - Torque sensor adjusting apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable adjustment of high accuracy by adjusting a torque sensor in a state where an ECU (Electric power stearing Control Unit) is connected. <P>SOLUTION: A predetermined torque is applied to the torque sensor 4 from a reference torque generator 9, and a torque signal is input into an inspection apparatus 7 via an A/D converter 110 of the ECU 1. The inspection apparatus 7 provides a command to the adjusting apparatus 8 based on the torque signal, and adjusts the neutral voltage and gain of the torque sensor 4. Since the neutral voltage and gain in addition to the A/D conversion error in the ECU 1 are adjusted, the error of the torque signal in an actual operation can be minimized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a torque sensor adjustment device and method, and more particularly to a torque sensor adjustment device and method for adjusting a torque sensor in a state where the torque sensor and a control device are connected.

  A torque sensor is widely used as a device for detecting torque. For example, a torque sensor is also used to detect steering torque in a power steering device. As is well known, the power steering device is a torque sensor that detects the operation of the steering wheel and the movement of the vehicle by the driver, and an electric power that calculates the auxiliary steering force based on a digital signal obtained by A / D converting the torque signal from the torque sensor. A steering control unit (ECU), an electric motor that generates rotational torque based on an output signal from the ECU, a reduction gear that transmits the rotational torque to the steering mechanism, and the like are provided.

  As a characteristic required for such a torque sensor, when a torque is not applied, a predetermined neutral voltage representing zero torque is accurately output, and a voltage corresponding to the applied torque is accurately output. Etc. are required. For this reason, it is necessary to adjust the neutral voltage, the detection gain, and the like in the adjustment process before the factory shipment of the torque sensor.

  As a conventional torque sensor adjusting device, for example, a device disclosed in JP-A-6-174777 has been devised. In this adjusting device, the torque sensor is connected to the inspection device alone, and the torque sensor is adjusted based on the torque signal output from the torque sensor while applying a predetermined torque to the torque sensor. For example, when no torque is applied to the torque sensor, the torque sensor is adjusted so that the torque signal becomes a neutral voltage. Further, the gain of the torque sensor is adjusted so that a correct voltage is output when a reference torque is applied.

However, in the conventional adjustment device, since the torque signal is measured and adjusted by the torque sensor alone, when the torque sensor is connected to the ECU, it shifts to the neutral voltage of the torque signal due to an A / D conversion error or the like in the ECU. Sometimes occurred. That is, even if accurate adjustment is performed with the torque sensor alone, an error occurs in the torque signal when connected to the ECU, and as a result, torque control by the ECU may become inaccurate.
JP-A-6-174777

  The present invention has been made in view of the above-described problems, and a problem to be solved by the present invention is that a highly accurate adjustment can be realized by adjusting the torque sensor in a state where the torque sensor is connected to the ECU. A torque sensor adjusting apparatus and method are provided.

  In order to solve the above-mentioned problem, the present invention is a torque sensor adjusting device for adjusting a torque sensor capable of outputting a torque signal according to an applied torque, and is connectable to the torque sensor. An inspection unit that inputs and inspects the torque signal via a control device that performs predetermined torque control based on the torque signal, and an adjustment unit that adjusts the torque sensor based on the inspection.

The adjusting means can adjust a neutral voltage of the torque signal.
Furthermore, the present invention further includes reference torque generating means for applying a predetermined reference torque to the torque sensor, and the adjusting means is configured to apply the torque based on the torque signal when the reference torque is applied to the torque sensor. The gain of the sensor can be adjusted.

The adjusting means adjusts the torque sensor by operating a variable resistor provided in the torque sensor.
The torque sensor includes a memory for storing a correction signal given from the adjustment unit, and corrects the torque sensor based on the correction signal stored in the memory.

  According to the present invention, the inspection means inputs the torque signal from the torque sensor via the control device and inspects the torque signal. Further, the adjusting means adjusts the torque sensor based on the inspection result. For this reason, since inspection and adjustment can be performed based on the torque signal recognized by the control device, even if a torque signal reading error occurs in the control device, the torque sensor is adjusted including the error. be able to. Therefore, highly accurate torque control can be realized in the control device.

  For example, even if a deviation occurs in the neutral voltage of the torque signal due to an A / D conversion error in the control device, the torque sensor can be adjusted based on the torque signal after A / D conversion. For this reason, the shift | offset | difference of the neutral voltage in a control apparatus can be eliminated.

  According to the present invention, the gain of the torque sensor can be adjusted by applying a predetermined reference torque to the torque sensor. As described above, even if a torque signal reading error occurs in the control measure, high-precision gain adjustment can be performed by adjusting the torque sensor including the error.

further. By automatically adjusting the variable resistance provided in the torque sensor using the adjusting means, the torque sensor can be adjusted efficiently.
Further, by providing the torque sensor with a memory for storing the correction signal given from the adjusting means, the torque sensor can be adjusted based on the correction signal stored in the memory. According to the present invention, it is not necessary to use a variable resistor that is likely to change with time, and therefore high-precision adjustment can be performed.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(First embodiment)
The torque sensor adjustment device according to the present embodiment can adjust various torque sensors with high accuracy. Here, a torque sensor used in the electric power steering device will be described.

  FIG. 1 is a schematic view of an electric power steering apparatus. In this figure, the end of the steering shaft 62 coupled to the handle 61 is connected to the steering shaft 65 via universal joints 63 and 64. Further, a rack and pinion 66 and a wheel tie rod 67 are provided at the end of the steering shaft 65, and the rotational movement of the handle 61 is converted into the axial movement of the tie rod 67.

  A torque sensor 4, a motor 3, and a reduction gear 31 are provided at the end of the steering shaft 65. The torque sensor 4 can detect the steering torque of the handle 61 and output a torque signal to the ECU 1. The rotational torque of the motor 3 is transmitted to the rack and pinion 66 through the reduction gear 31.

  The ECU 1 calculates the auxiliary steering torque based on the detection signal from the torque sensor 4 and the vehicle speed signal from the vehicle speed sensor 2 as described above, and sends a drive signal based on the calculation result to the motor 3. The ECU 1 is directly supplied with electric power from the power source 5 and is connected in parallel with the power source 5 via the ignition key 5a. When the ignition key 5a is turned on, current is supplied to the ECU 1. ing.

  As described above, the torque signal of the torque sensor 4 is input to the ECU 1, and the torque sensor 4 is used while being connected to the ECU 1. The torque sensor adjusting device according to the present embodiment makes it possible to perform highly accurate adjustment by adjusting the torque sensor 4 in a state where the torque sensor 4 and the ECU 1 are connected to each other.

  FIG. 2 is a block diagram of the torque sensor adjusting device according to the present embodiment. This torque sensor adjustment device includes an inspection device 7 and an adjustment device 8, and the torque sensor 4 and the ECU 1 are to be inspected. The inspection device 7 detects a torque signal via the ECU 1 and adjusts the torque sensor 4. The adjusting device 8 has a function of automatically adjusting the variable resistance in the torque sensor 4 in accordance with an instruction from the inspection device 7. That is, the adjustment device 8 includes a step motor for adjusting the variable resistance, an I / O interface for receiving a signal output from the inspection device 7, a controller for controlling the step motor based on the signal, and the like. ing. The reference torque generator 9 includes a motor, a torque sensor, and the like, and applies a measurement reference torque to the torque sensor 4. For example, when the neutral voltage of the torque sensor 4 is adjusted, the torque applied from the torque generator 9 to the torque sensor 4 becomes zero. On the other hand, when adjusting the gain of the torque sensor 4, a predetermined reference torque is applied to the torque sensor 4.

  The inspection device 7 includes a CPU 70, a memory 71, an I / O interface 72, a controller 73, an external storage device 74, and a display 75. The I / O interface 72 has a function of inputting a digital torque signal via the ECU 1 and outputting the torque signal to the CPU 70. The CPU 70 determines the adjustment amount of the torque sensor 4 so that the input torque signal becomes a predetermined reference value. The controller 73 can control the adjustment device 8 by outputting a signal representing the determined adjustment amount to the adjustment device 8. The controller 73 has a function of controlling the reference torque generator 9 by outputting an instruction signal to the reference torque generator 9. That is, based on an instruction from the controller 73, the reference torque generator 9 can apply the reference torque to the torque sensor 4. The external storage device 74 can store a processing program of the inspection device 7 or data of adjustment results of the individual torque sensors 4. Further, by recording the serial numbers of the torque sensor 4 and the ECU 1 together with the survey result data in the external storage device 74, it is possible to confirm the torque sensor 4 and the ECU 1 to be connected when the power steering device is manufactured.

  FIG. 3 is a partially cutaway view of the torque sensor 4. The torque sensor 4 is a non-contact type and includes a sleeve 41, a sensor shaft 42, a coil assembly 43, and a torsion bar 44. The sensor shaft 42 is made of a magnetic material, and a cavity along the axis is provided inside. Further, around the sensor shaft 42, protrusions 42a and grooves 42b are alternately formed. A rod-like torsion bar 44 is disposed in a cavity provided inside the sensor shaft 42, and one end of the torsion bar 44 and one end of the sensor shaft 42 are connected to a steering shaft 65. The other end of the torsion bar 44 is connected to an output shaft (not shown) together with the sleeve 41. For this reason, when torque is applied to the steering shaft 65, the torsion bar 44 is twisted, and the relative position between the sensor shaft 42 and the sleeve 41 changes.

  The sleeve 41 has a cylindrical shape and is made of a nonmagnetic material such as aluminum. Around the sleeve 41, rectangular windows 41a are formed at equal intervals. Further, a plurality of windows 41b are formed at positions shifted by a half pitch with respect to these windows 41a. A coil assembly 43 having detection coils L1 and L2 is provided at a position facing these windows 41a and 41b.

  In the torque sensor 4 configured as described above, a magnetic field is generated by passing an alternating current through the detection coils L1 and L2. An eddy current is generated in the sleeve 41 by this magnetic field, and a magnetic field is generated in the windows 41a and 41b by the eddy current. The magnetic fields in the windows 41a and 41b are configured to be detected by the detection coils L1 and L2.

  For example, when no torque is applied to the handle 9, the torsion bar 44 is not twisted, and the protrusion 42a of the sensor shaft 42 is positioned between the windows 41a and 41b. In this case, the magnetic flux densities in the windows 43a and 43b are equal, and the inductances in the detection coils L1 and L2 are also equal. On the other hand, when torque is applied to the handle 9 and the torsion bar 44 is twisted, the positions of the protrusion 42a and the windows 41a and 41b change. Depending on the twisting direction of the torsion bar 44, the projection 42a approaches either the window 41a or the window 41b. For this reason, the magnetic flux density in each of the windows 41a and 41b changes, and the inductance in the detection coils L1 and L2 changes.

That is, as shown in FIG. 4, the inductances of the detection coils L1 and L2 have a so-called cross characteristic and change in opposite directions with respect to the steering torque. Further, when the steering torque is zero, the inductances of the detection coils L1 and L2 are equal. The inductance in each of the detection coils L1 and L2 having such characteristics is converted into a main torque signal and a sub torque signal by a signal processing circuit, and is output from the torque sensor 4.

  FIG. 5 is a block diagram of a signal processing circuit of the torque sensor 4. This signal processing circuit includes an oscillation unit 401, a current amplification unit 402, resistors R1 and R2, detection coils L1 and L2, a sub amplification / full wave rectification unit 403, a main amplification / full wave rectification unit 404, a sub smoothing / neutral adjustment unit. 405, a main smoothing / neutral adjustment unit 406, a monitoring unit 407, and variable resistors VR1, VR2, VR3, and VR4.

  The oscillating unit 401 is configured by a transmission circuit including a ceramic oscillator, a crystal oscillator, or an LC circuit, and is for generating an AC signal having a predetermined frequency. The current amplifying unit 402 is configured by a current amplifying circuit such as a transistor, and is necessary for driving the resistors R1 and R2 and the detection coils L1 and L2 by performing current amplification of the AC signal generated by the oscillation unit 401 Generate current.

  As described above, the detection coils L1 and L2 are for detecting a change in magnetic flux in the windows 41a and 41b formed around the sleeve 41. As the torsion bar 44 is twisted, the two detection coils L1 and L2 are detected. The magnetic flux changes in opposite phases to each other. That is, as shown in FIG. 4, when the right steering torque is applied to the torque sensor 4, the inductance L10 of the detection coil L1 increases and the inductance L20 of the coil detection L2 decreases. Further, when the left steering torque is applied to the torque sensor 4, the inductance L10 of the detection coil L1 decreases and the inductance L20 of the coil L2 increases. Thus, each inductance in the detection coils L1 and L2 changes in the opposite direction with respect to the torque.

  The sub-amplification / full-wave rectification unit 403 and the main amplification / full-wave rectification unit 404 are configured by a differential amplifier, a rectification circuit, and the like, amplify the difference in inductance change in each of the detection coils L1 and L2, and It has a function of removing components. The sub smoothing / neutral adjustment unit 405 and the main smoothing / neutral adjustment unit 406 are for setting the voltages of the sub torque signal and the main torque signal based on the reference voltage supplied from the ECU 1. That is, with the reference voltage 3.3V as a reference, the voltages of the main torque signal and the sub torque signal are corrected, and each torque neutral voltage is set to 2.5V. The monitoring unit 407 has a function of monitoring abnormality of the oscillation unit 401, disconnection of the detection coils L1, L2, and the like. When the monitoring unit 407 detects an abnormality, for example, one voltage of the main torque signal and the sub torque signal is forcibly set to an abnormal value. Thereby, the ECU 1 can detect an abnormality of the torque sensor 4.

  The variable resistor VR1 is connected to the main amplification / full wave rectification unit 404 and is used to adjust the detection gain of the main torque signal. This variable resistor VR1 is of a so-called semi-fixed type, and after being adjusted by the adjusting device 8, it cannot be adjusted from the outside unless the casing of the main torque sensor 4 is opened. Similarly, the variable resistor VR2 is connected to the sub-amplification / full-wave rectification unit 403 and is used to adjust the detection gain of the sub-torque signal.

  The variable resistor VR3 is connected to the main smoothing / neutral adjustment unit 406 and adjusts the neutral voltage of the main torque signal. That is, when no torque is applied to the torque sensor 4, the variable resistor VR3 is adjusted so that the main torque signal becomes a neutral voltage of 2.5V. Similarly, the variable resistor VR4 is for adjusting the neutral voltage of the sub torque signal in the sub smoothing / neutral adjustment unit 405.

  FIG. 6 is a block diagram illustrating a hardware configuration of the ECU 1. The ECU 1 includes an A / D converter 110, an I / O interface 111, 112, a CPU 113, a ROM 114, a RAM 115, a flash ROM 116, a PWM 117, a motor drive circuit 119, a motor current detection circuit 120, a bus 121, and a reference voltage circuit 130. It is configured.

  The A / D converter 110 converts the main torque signal and the sub torque signal output from the torque sensor 4 into digital signals. The I / O interface 111 counts vehicle speed pulses from the vehicle speed sensor 2 and converts them into digital signals. The I / O interface 112 is for outputting a torque signal to the inspection device 7. That is, the torque signal digitized by the A / D converter 110 is output to the inspection device 7 via the I / O interface 112. For this reason, even if a torque signal conversion error occurs in the A / D converter 110, the torque sensor 4 can be adjusted including the error.

  The ROM 114 is used as a memory for storing a control program for the motor 3 and a fail-safe function program, and the RAM 115 is used as a work memory for operating the program. The flash ROM 116 is a memory that can retain the stored contents even after the power is shut off, and can record a failure diagnosis result and the like.

  The PWM controller 117 is for converting a signal representing the torque of the motor 3 into a pulse width modulated signal. The motor drive circuit 119 is composed of an inverter circuit, and is for generating drive power based on a signal output from the PWM controller 117. The motor current detection circuit 120 is for detecting a counter electromotive voltage generated in the motor 3, and this counter electromotive voltage is converted into a digital signal by the A / D converter 110 and then sent to the CPU 113. ing.

The reference voltage generation circuit 130 is composed of an operational amplifier or the like, and is for generating a reference voltage of 3.3 V, for example, by dropping the voltage of the power supply 5. This reference voltage is supplied to the torque sensor 4 and used to generate a torque midpoint voltage of 2.5V.
FIG. 7 shows a functional block diagram of the ECU 1. In this figure, a current command value calculation unit 12, a current control unit 14, and a failure diagnosis unit 15 function by the CPU 113 in the ECU 1.

The main torque signal and the sub torque signal from the torque sensor 4 and the vehicle speed signal from the vehicle speed sensor 2 are input to the current command value calculation unit 12. That is, the main torque signal and the sub torque signal are A / D converted by the A / D converter 110 and then input to the CPU 113.
The current command value calculation unit 12 has a function of calculating the current command value I based on the torque signal, the vehicle speed signal, the detected current i of the motor, and the detected voltage e. The current command value I represents a drive current value supplied to the motor 3, and control is performed so that a drive current equal to the current command value I is supplied to the motor 3. Moreover, the vehicle speed pulse from the vehicle speed sensor 2 is input to the current command value calculation unit 12, and it is possible to determine the steering assist force according to the vehicle speed.

  The current command value calculation unit 12 has handle return compensation and motor maximum current control. For example, the steering wheel return compensation performs control for restoring the steering wheel 9 to the neutral position. In general, in the electric power steering apparatus, the self-aligning torque tends to be weak due to the influence of the reduction gear 31 and the like, and thus the handle is difficult to return to the neutral position. Therefore, the compensation current value for detecting the motor angular velocity by detecting the motor terminal voltage e and the motor current i when the motor 3 is rotated by the action of the self-aligning torque and restoring the handle to the neutral position. Is calculated.

  The motor current detection circuit 120 detects the current supplied to the motor 3 and outputs a signal of the detection current i. The detected current i is fed back to the adder 13 and input to the current command value calculation unit 12. The adder 13 calculates a deviation Δi between the detected current i and the current command value I and outputs it to the current control unit 14.

  The current control unit 14 includes a differential calculator, a proportional calculator, and an integral calculator, and has a function of performing control so that the deviation Δi becomes zero. The differential compensator is provided to improve the response speed of the control, and the proportional calculator is for multiplying the deviation Δi by a predetermined proportional coefficient. Further, the integral calculator calculates the integral value on the time axis of the deviation Δi, and performs control so that the steady value of the deviation Δi becomes zero.

The failure diagnosis unit 15 is for executing fail-safe processing by monitoring the voltage values of the reference voltage, the main torque signal, and the sub torque signal. That is, when the main torque signal and the sub torque signal are outside the predetermined threshold range, it is determined that the torque sensor 4 is abnormal, and a command for prohibiting assist is provided to the current command value calculation unit 12.
Next, the operation of the torque sensor adjustment device according to the present embodiment will be described with reference to the flowcharts of FIGS.

  FIG. 8 is a main flowchart of the torque sensor adjusting device according to the present embodiment. First, the torque sensor 4 and the ECU 1 are connected, and these are set in the inspection system (step S1). That is, the reference torque generator 9 is connected to the torque sensor 4 input shaft, and the adjusting driver of the adjusting device 8 is brought into contact with the variable resistors VR1 to VR4 of the torque sensor 4. In this state, the ECU 1 is connected to the inspection device 7, and electric power is supplied from the inspection device 7 to the ECU 1 (step S2). Electric power is applied to the torque sensor 4 via the ECU 1, and the ECU 1 and the torque sensor 4 are activated. At this time, the inspection device 7 confirms the connection between the torque sensor 4 and the ECU 1 by determining whether or not a torque signal is input. Subsequently, the inspection device 7 adjusts the neutral voltage of the torque sensor 4 (step S3) and adjusts the gain (step S4). As described above, the processes of steps S3 to S4 are repeatedly executed until the adjustment of the torque sensor 4 to be adjusted is completed (YES in step S5).

  FIG. 9 is a flowchart showing details of the neutral voltage adjustment process. First, the inspection device 7 gives an instruction to the reference torque generator 9 via the controller 73, and zeros the torque applied to the input shaft of the torque sensor 4 (step S301). The torque signal output from the torque sensor 4 is input to the A / D converter 110 of the ECU 1 and digitized (step S302). The digital torque signal is input to the I / O interface 72 of the inspection apparatus 7 via the CPU 113 and the I / O interface 112 of the ECU 1 (step S303). The inspection device 7 calculates a difference between the value of the torque signal and a predetermined reference voltage of 2.5 V as an error voltage (step S304). The inspection device 7 gives an instruction to the adjustment device 8 so that the error voltage becomes zero, and adjusts the variable resistances VR3 and VR4 of the torque sensor 4 (step S305). By adjusting the variable resistors VR3 and VR4, the neutral voltage in the sub smoothing / neutral adjustment unit 405 and the main smoothing / neutral adjustment unit 406 is corrected. In this manner, the inspection apparatus 7 repeatedly executes the processes of steps S302 to S305 until the error voltage falls within the allowable range (YES in step S306). When the error voltage is within the allowable range, that is, when the adjustment of the neutral voltage of the torque signal is completed, the process returns to the main flowchart of FIG.

  FIG. 10 is a flowchart showing details of the gain adjustment processing. At the time of gain adjustment, the inspection device 7 gives an instruction to the reference torque generator 9 and applies a predetermined reference torque to the torque sensor 4 (step S401). The torque sensor 4 outputs a torque signal corresponding to the applied torque, and the A / D converter 110 of the ECU 1 digitizes the torque signal (step S402). The digitized torque signal is input to the inspection device 7 via the I / O interface 112 of the ECU 1 (step S403). The inspection device 7 calculates an error between the torque signal and a predetermined reference voltage (step S404). This reference voltage is predetermined with respect to the reference torque. The inspection device 7 gives an instruction to the adjustment device 8 to adjust the variable resistors VR1 and VR2 so that the error voltage falls within the allowable range. Thereby, the amplification factors in the sub-amplification / full-wave rectification unit 403 and the main amplification / full-wave rectification unit 404 are corrected, and the gains of the main torque signal and the sub-torque signal are adjusted. The inspection device 7 repeatedly executes the processes of steps S402 to S405 described above until the gain error of the torque signal falls within the allowable range (YES in step S406). If the error falls within the allowable range, the process returns to the main flowchart of FIG.

  As described above, according to the torque sensor adjusting device according to the present embodiment, by adjusting the torque sensor 4 in a state where the torque sensor 4 is connected to the ECU 1, the A / D conversion error and the like in the ECU 1 are included. It becomes possible to correct. That is, since the torque sensor 4 is corrected based on the torque signal recognized by the ECU 1, the torque control in the ECU 1 can be executed with high accuracy. Further, there is an advantage that the connection between the torque sensor 4 and the ECU 1 can be confirmed at the same time.

(Second Embodiment)
Next, a torque sensor adjusting device according to the second embodiment will be described. FIG. 11 is a block diagram of a processing circuit of the torque sensor 4 according to the present embodiment. The torque sensor 4 has a digital signal adjustment function instead of the variable resistors VR1 to VR4 according to the first embodiment. That is, the torque sensor 4 includes a controller 410, an I / O interface 411, a D / A converter 412, a temperature sensor 413, a flash memory 414, a sub-amplification / full-wave rectification unit 403 ′, a main amplification / full-wave rectification unit 404 ′. , A sub-smoothing / neutral adjustment unit 405 ′, a main smoothing / neutral adjustment unit 406 ′, and the like.

  The sub-amplification / full-wave rectification unit 403 ′ and the main amplification / full-wave rectification unit 404 ′ include a voltage control gain circuit, and can adjust the gain based on a given correction voltage. Similarly, the sub smoothing / neutral adjustment unit 405 ′ and the main smoothing / neutral adjustment unit 406 ′ can adjust the neutral voltage based on a given correction instruction. The I / O interface 411 is for inputting the correction signal output from the adjustment device 8. The controller 410 has a function of storing the input correction signal in the flash memory 414 and performing correction based on the signal. The D / A converter 412 converts the digital correction signal into an analog correction signal, and sub-amplification / full-wave rectification unit 403 ′, main amplification / full-wave rectification unit 404 ′, sub-smoothing / neutral adjustment unit 405. ', For supplying to the main smoothing / neutral adjustment unit 406'.

  The temperature sensor 413 detects the temperature of the torque sensor 4 and applies a temperature signal to the controller 410 to correct the temperature of the torque signal. In the present embodiment, temperature correction can also be executed in a state where the ECU 1 is connected. The flash memory 414 is a non-volatile memory that can store a correction signal given from the adjustment device 8. That is, it is possible to hold the value of the correction signal even after the torque sensor 4 is turned off and to execute correction based on the correction signal.

  Other configurations and operations according to the present embodiment are substantially the same as those according to the first example. That is, adjustment of the torque sensor 4 can be performed in a state where the ECU 1 and the torque sensor 4 are connected. According to the present embodiment, by using a voltage control correction circuit instead of the variable resistors VR1 to VR4, it is possible to avoid a correction error associated with the secular change of the variable resistors VR1 to VR4. Further, by correcting the neutral voltage and gain correction values based on the temperature sensor 413, highly accurate correction can be performed.

  Although the present embodiment has been described above, the present invention is not limited to the above-described configuration, and can be changed without departing from the spirit of the present invention. For example, the type of the torque sensor is not limited to the non-contact type inductance detection type, and the present invention can be applied to other types of torque sensors such as a contact type. Furthermore, the adjustment method is not limited to the above flowchart, and can be changed as long as the same function can be realized. Moreover, although the above-mentioned embodiment can adjust a torque sensor automatically, you may perform adjustment work manually. Further, the adjustment items of the torque sensor are not limited to the neutral voltage and the gain, and the present invention can also be applied to a temperature detection voltage or the like.

1 is a schematic diagram of a power steering apparatus according to a first embodiment. It is a block diagram of the torque sensor adjustment device concerning a 1st embodiment. It is a partially broken view of the torque sensor according to the first embodiment. It is a graph for demonstrating the characteristic of the torque signal which concerns on 1st Embodiment. It is a block diagram of a processing circuit of the torque sensor according to the first embodiment. It is a block diagram of ECU which concerns on 1st Embodiment. It is a functional block diagram of ECU which concerns on 1st Embodiment. It is a main flowchart showing operation | movement of the torque sensor adjustment apparatus which concerns on 1st Embodiment. It is a flowchart showing the detail of the neutral voltage adjustment which concerns on 1st Embodiment. It is a flowchart showing the detail of the gain adjustment which concerns on 1st Embodiment. It is a block diagram of the processing circuit of the torque sensor which concerns on 2nd Embodiment.

Explanation of symbols

1 ECU
4 Torque sensor 7 Inspection device 8 Adjustment device 9 Reference torque generator 110 A / D converter 403 Sub amplification / full wave rectification unit 404 Main amplification / full wave rectification unit 404 Sub smoothing / neutral adjustment unit 405 Main smoothing / neutral adjustment unit

Claims (10)

A torque sensor adjustment device for adjusting a torque sensor capable of outputting a torque signal according to an applied torque,
Inspection means for inputting and inspecting the torque signal via a control device capable of being connected to the torque sensor and performing predetermined torque control based on the torque signal;
A torque sensor adjusting device comprising: adjusting means for adjusting the torque sensor based on the inspection.   The torque sensor adjusting apparatus according to claim 1, wherein the adjusting unit is capable of adjusting a neutral voltage of the torque signal.   Reference torque generating means for applying a predetermined reference torque to the torque sensor is further provided, and the adjusting means can adjust the gain of the torque sensor based on the torque signal when the reference torque is applied to the torque sensor. The torque sensor adjusting device according to claim 1, wherein   The torque sensor adjustment apparatus according to claim 1, wherein the adjustment unit adjusts the torque sensor by operating a variable resistor provided in the torque sensor.   The torque sensor adjustment according to claim 1, wherein the torque sensor includes a memory that stores a correction signal given from the adjustment unit, and corrects the torque sensor based on the correction signal stored in the memory. apparatus. A torque sensor adjustment method for adjusting a torque sensor capable of outputting a torque signal according to applied torque,
An inspection step for inputting and inspecting the torque signal via a control device that is connectable to the torque sensor and performs predetermined torque control based on the torque signal;
A torque sensor adjustment method comprising: an adjustment step of adjusting the torque sensor based on the inspection.   The torque sensor adjustment method according to claim 6, wherein in the adjustment step, a neutral voltage of the torque signal can be adjusted.   A reference torque generation step of applying a predetermined reference torque to the torque sensor is further provided, and the adjustment step can adjust the gain of the torque sensor based on the torque signal when the reference torque is applied to the torque sensor. The torque sensor adjustment method according to claim 6, wherein:   The torque sensor adjustment method according to claim 6, wherein the adjustment step adjusts the torque sensor by operating a variable resistor provided in the torque sensor. The torque sensor adjustment according to claim 6, wherein the torque sensor includes a memory for storing the correction signal given in the adjustment step, and corrects the torque sensor based on the correction signal stored in the memory. Method.

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