JP2001221698A - Detector of torque - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the detector of torque, capable of performing both the transmissions of electric power supply of a fixed side 1 to a rotary shaft side 2 and measured output of the torque detected by a load cell B6, from the rotary shaft side 2 to the fixed side 1. SOLUTION: Since a coil B1 fixed on the rotary shaft side 2 is positioned to perform electromagnetic induction at a distance L of a few millimeters in a coil A1 fixed on the fixed side 1, both the transmissions of the electric power supply of the fixed side 1 to the rotary shaft side 2 by electromagnetic between the coils A1, B1 and the measured output of the torque detected by a load cell B6 from the rotary shaft side 2 to the fixed side 1 are conducted, and various control signals are transmitted from the fixed side 1 to the rotary shaft side 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a torque detecting device.

[0002]

2. Description of the Related Art A strain gauge is provided on a rotating shaft acting on a torque to detect and measure the torque, and a signal is extracted to the outside by a radio wave by induction by a slip ring and a slider, a core and a coil, and radio waves. ing.

[0003]

Conventionally, a slip ring and a slider are usually used for taking out to the outside, but such mechanical parts are liable to break down. Since the use of radio waves and optical elements has low energy, there are difficulties in power supply, stability, interference, and the like.

[0004]

According to a first aspect of the present invention, a coil B1 fixed to the rotating shaft 2 is positioned in a coil A1 fixed to the fixed side 1 so as to be electromagnetically induced at a distance L of several mm. By the electromagnetic induction between the coil A1 and the coil B1, the power a2 is supplied from the fixed side 1 to the rotating shaft side 2 and the measurement signal b1 of the torque detected by the load cell B6 from the rotating shaft side 2 to the fixed side 1 is transmitted. It is a torque detecting device characterized by the above-mentioned.

According to a second aspect of the present invention, the various control signals c2 are transmitted from the fixed side 1 to the rotary shaft side 2 by electromagnetic induction between the coil A1 and the coil B1. Is a detection device.

[0006]

FIG. 1 is a circuit diagram schematically showing an embodiment of the present invention, FIG. 2 is a sectional view showing a specific arrangement of the coils A1 and B1, and FIG. It is. In FIG. 1, 1 is a fixed side, and 2 is a rotating shaft side on which a torque is acting. Coil A1 fixed to fixed side 1
Inside, a coil B1 fixed to the rotating shaft side 2 is positioned for electromagnetic induction at a distance L of several mm. FIG. 2 shows this coil A
1, a cross-sectional view showing a specific arrangement of the coil B1, wherein 1a is a cylindrical cover provided on the fixed side 1 thereof.

A power oscillator A2 is connected to the coil A1, and a power switch transistor T is connected to the oscillator A2.
1 and the output AA1 of the microcomputer MC1 is input to the base of the transistor T1 via the diode D1. The input AC power supply of 100 V is rectified by the DC voltage power supply unit 3, the output voltage V1 is connected to the transistor T1, and the microcomputer MC1 is driven by the output voltage of 5V.

[0008] The measurement voltage induced in the coil A1 is connected to the input AA3 of the microcomputer MC1 via the reception amplifier A3 also serving as a band-pass filter. The digital measurement output AA4 of the microcomputer MC1 is connected to a DC output unit 5 for analog measurement via a D / A converter A4 and an amplifier A5.

The coil B1 constitutes a constant voltage circuit B5 with a smoothing circuit BV comprising a diode D1 and an electrolytic capacitor B3 of several thousand μF. The output power supply V2 comprises a microcomputer MC2 and strain gauges 4, 4, 4, 4. Drive the load cell B6. This load cell B6 has four strain gauges 4, 4, 4, and 4 attached to a slightly thinned portion of the rotating shaft 2 where a torque is acting, and connected to a bridge circuit. The analog measurement output of the torque of the load cell B6 is converted into a digital signal via an amplifier B7 and an A / D converter B8, and becomes a microcomputer MC.
2 BB4. The measurement output BB3 of the microcomputer MC2 is connected to the coil B1.

The output AA2 for switching the oscillation frequency of the microcomputer MC1 is input to the oscillator A2. On the other hand, the transmission frequency switching signal induced in the coil B1 is connected to the input BB1 of the microcomputer MC2 via the frequency detection amplifier B2.

Next, the operation of this device will be described. Power a supplied from output AA1 of microcomputer MC1
2 intermittently operates at 5─10 ms, for example, 9 ms, and pauses for 1 ms as shown by the timing of the signal a1 in FIG.

Oscillator A2 is set to 80KC by this power a2.
A high frequency current of f1 or 86KCf2 is oscillated and flows through the coil A1 as shown by a3 in FIG. As a result, a high-frequency current a4 is induced in the coil B1 as shown in FIG. 3, and this high-frequency current a4 is rectified by the smoothing circuit BV as shown by a5 in FIG. Driving the load cell B6.

On the other hand, the measured output b1 of the analog torque detected by the load cell B6 during the idle period is the amplifier B
7, a digital signal b2 via an A / D converter B8 and an input BB4, which is input to the microcomputer MC2 to be processed as transmission data b3, and this transmission data b
3 flows from the measurement output BB3 to the coil B1, and the coil A1
The digital measurement voltage b4 is amplified by the amplifier A3 to become a measurement signal b5, input to the input AA3 of the microcomputer MC1, and output as a measurement signal b6 from the measurement output AA4 of the microcomputer MC1. Then, the signal is output as a measurement signal b7 to the DC output unit 5 for analog measurement via the D / A converter A4 and the amplifier A5, and is used for measurement.

The signal c1 of the output AA2 for switching the oscillation frequency of the microcomputer MC1 is input to the oscillator A2, and the high frequency current oscillated by the oscillator A2 is reduced to 1/10.
It can be switched to 0KC, for example 80KC or 86KC. For example, the high-frequency current c1 is a digital signal as shown in FIG. 3 as a 0 signal at 80 KC and a 1 signal at 86 KC. The digital signal c1 is sent to the input BB1 for switching the oscillation frequency of the microcomputer MC2 through the coil A1, the coil B1, and the amplifier B2, and is set as a digital control signal c2. The digital control signal c2 enables various controls such as a change in the amplification of each amplifier, a limit torque alarm, temperature detection by a thermistor, and pressure detection.

FIG. 4 is a flowchart of the microcomputer MC1. When the power is turned on in step P1, the work RAM I / O port and the like in the computer are initialized in step P2, the output AA1 is turned on in step P3 to generate an induced electromotive force in the coil A1, and the output AA2 generates the induced frequencies f1 and f2. Is output at a predetermined timing. Note that the digital control signal c2
When there is no need to send the signal c1 having only the induction frequency f1
Is output. This signal c1 stops during the idle period. Next, in step P4, the measurement signal b5 is received by the input AA3.
Next, in step P5, the measurement signal b6 is converted to D / A by the input AA4.
The signal is sent to converter A4 and returns to step P3.

FIG. 5 is a flow chart of the microcomputer MC2. When the power is turned on in step Q1, a work RAM I / O port or the like in the computer is initialized in step Q2, a digital measurement voltage b2 is taken in by input BB4 in step Q3, and it is determined in step Q4 whether or not a pause period is present. If no, the signal c1 is captured in step Q5, and the process returns to step Q3.

If yes in step Q4, the measured voltage b2 is converted into data in step Q6, the transmission data b3 is transmitted from the measurement output BB3, and it is determined in step Q7 whether or not the signal c1 has been received. Return. If yes in step Q7, the process returns to step Q3.

[0018]

As described above, according to the first aspect of the present invention, the coil B1 fixed to the rotating shaft side 2 is positioned in the coil A1 fixed to the fixed side 1 so as to be electromagnetically induced at a distance L of several mm. Because of the electromagnetic induction between the coil A1 and the coil B1, both the power supply from the fixed side 1 to the rotating shaft side 2 and the measurement output of the torque detected by the load cell B6 from the rotating shaft side 2 to the fixed side 1 are transmitted. Can be performed, the structure is simple, the cost is low, and the operation is reliable.

According to a second aspect of the present invention, the coil A1
Various control signals can be transmitted from the fixed side 1 to the rotating shaft side 2 by electromagnetic induction between the motor 1 and the coil B1, which is convenient.

[Brief description of the drawings]

FIG. 1 is a circuit diagram schematically showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a specific arrangement of the coils A1 and B1.

FIG. 3 is a graph of a voltage of each part.

FIG. 4 is a flowchart of the microcomputer MC1.

FIG. 5 is a flowchart of the microcomputer MC2.

[Explanation of symbols]

 1 Fixed side A1 Coil 2 Rotation axis side B1 Coil L Distance

Claims (2)

[Claims] Coil (A1) fixed to fixed side (1)
Inside the coil (B1) fixed to the rotating shaft side (2) is several meters.
m, and the electromagnetic induction between the coil (A1) and the coil (B1) supplies electric power (a2) from the fixed side (1) to the rotating shaft side (2) and rotates the rotating shaft. Load cell (B6) from side (2) to fixed side (1)
Transmitting a torque measurement signal (b1) detected in step (a). 2. A control signal (c2) is transmitted from a fixed side (1) to a rotating shaft side (2) by electromagnetic induction between the coil (A1) and the coil (B1). Item 2. The torque detecting device according to Item 1.