JP2001133349A - Torque calibrating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the dispersion of precision depending on the magnitude of the torque applied to a torque meter in a torque calibrating apparatus. SOLUTION: This torque calibrating apparatus 1 comprises a lever 10 connected to the measurement shaft of the torque meter to be calibrated and integrally rotatable with the measurement shaft, a bearing 12 for supporting the lever 10 in a rotatable state, and a torque application means 30 capable of applying torque to the torque meter 2. The torque application means 30 is constituted so as to change the torque to be applied to the torque meter 2 by changing the suspending position of weights 31a while keeping the total mass of the weights 31a suspended on the lever 10 constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lever connected to a measuring shaft of a torque meter to be calibrated and rotatable integrally with the measuring shaft, and a lever supporting portion for supporting the lever in a rotatable state. And a torque adding unit capable of adding a torque to the torque meter by suspending a weight on the lever.

[0002]

2. Description of the Related Art A lever connected to a measurement shaft of a torque meter to be calibrated and rotatable integrally with the measurement shaft, a lever support portion for supporting the lever in a rotatable state, and a weight attached to the lever Conventionally, a torque calibrating device having a torque adding means capable of applying a torque to a torque meter by suspending the torque meter, as shown in FIG. By doing so, the torque applied to the torque meter was changed.

[0003]

However, in the above-described conventional torque calibrating device, the torque applied to the torque meter is changed by increasing or decreasing the mass of the weight 60 suspended at one end of the lever 10, and thus the weight is changed. The lever support portion (here, lever 1)
0, the magnitude of the vertical force acting on the bearing 12) supporting the support shaft 11 is changed.
The magnitude of the frictional force acting in the direction of rotation of the motor changes.
Therefore, in the above-described conventional torque calibration device, the accuracy of the torque varies depending on the magnitude of the torque applied to the torque meter.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and is configured so that the frictional force acting in the rotating direction of the lever is always constant, and the torque applied to the torque meter is adjusted. It is an object of the present invention to provide a torque calibration device capable of reducing variation in accuracy due to the size of the torque.

[0005]

According to a first aspect of the present invention, there is provided a lever (2) connected to a measuring shaft of a torque meter (2) to be calibrated and rotatable integrally with the measuring shaft. 10), a lever supporting portion (for example, bearing 12 or the like) for supporting the lever in a rotatable state, and a torque capable of suspending a weight on the lever to apply a torque to the torque meter. In the torque calibrating device (1) provided with an additional means (30), the torque adding means suspends the weight while maintaining the total mass of the weight (31a) suspended on the lever constant. By changing the position, the torque applied to the torque meter is changed.

According to the first aspect of the present invention, the torque applying means changes the suspension position of the weight while maintaining the total mass of the weight suspended from the lever constant, thereby providing the torque meter with the torque. Because the applied torque is changed, the magnitude of the vertical force acting on the lever support and the magnitude of the frictional force acting in the direction of rotation of the lever are reduced by the magnitude of the torque applied to the torque meter. It is constant regardless. As a result, variations in accuracy due to the magnitude of the torque applied to the torque meter can be reduced, and errors due to the frictional force become constant, so that correction for the frictional force becomes easy. Thereby, it becomes possible to improve the calibration accuracy of the torque meter.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a perspective view showing a torque calibration device according to the present invention. FIG. 2 is a perspective view showing the vicinity of a torque meter mounting portion of the torque calibration device of FIG. FIG.
FIG. 2 is a block diagram showing a control device constituting the torque calibration device of FIG. 1 and various electric devices connected to the control device. FIG. 4 is a diagram for explaining a method of adding a weight to the lever of the torque calibration device of FIG.

As shown in FIG. 1, a torque calibrating device 1 according to this embodiment has a torque meter mounting portion 15 for mounting a torque meter 2 to be calibrated, and one of measurement axes of the torque meter 2 in the torque meter mounting portion 15. A lever 10 connected to the measuring shaft and rotating integrally with the measuring shaft; a servomotor 14 for adjusting the rotating position of the lever 10; a lever length measuring means 20 for measuring the horizontal length of the lever 10; It comprises a torque adding means 30 for suspending a weight (weight 31a,...) To apply torque to the torque meter 2, and a control device 50 (FIG. 3) for controlling the torque adding means 30 and the like.

The torque meter 2 has a measuring shaft for measuring torque. When the torque meter 2 is assembled to the torque meter mounting portion 15, one end of the measuring shaft is connected to the output of the servo motor 14 as shown in FIG. On the other hand, the other end of the measuring shaft is connected to the lever 10, and the flange-shaped mounting members 16,
.. Are connected. That is, the lever 10, the measurement axis of the torque meter 2, and the output axis of the servomotor 14
Each is connected in series so as to be able to transmit torque.

The lever 10 has a support shaft 11 provided at the center thereof supported by a bearing 12 exemplified as a lever support portion provided on the main body frame 1A (FIG. 1), and is rotatable with respect to the main body frame 1A. It has become. This lever 10
As shown in FIG. 2, a fishing rod fixing portion 13b which can be freely connected to a fishing rod 31b provided in a weight group 31 to be described later,
It is attached via a metal band 13a.

The servo motor 14 is, as shown in FIG.
It is installed on a movable table 17 that can move horizontally along a rail 18 provided at the upper end of the main body frame 1A.
The movable table 17 is moved in the measurement axis direction of the torque meter 2 (the direction in which the movable table 17 approaches and separates from the lever 10) when the torque meter 2 is attached and detached.

As shown in FIG. 3, the lever length measuring means 20 is constituted by, for example, a displacement meter of an optical system using a laser light source 21. The lever length measuring means 20 can be constituted by, for example, an eddy current type displacement sensor, a capacitance type displacement sensor, or the like.

As shown in FIGS. 1 to 3, the torque adding means 30 includes a plurality of types (here, three types) of weight groups 31,. , A table 32 on which the weight groups 31,.
Table 3 when exchanging the weight groups 31,.
, A torque range switching motor 33b for raising and lowering the table 32 in order to increase or decrease the load applied to the lever 10 (the number of weights 31a suspended from the lever 10); , A load cell 35 capable of detecting the load applied to the lever 10, and a torque range switching motor 3 under the control of the control device 50.
3b and a weight addition / removal controller 36 for controlling the weight switching motor 33a. For example, as shown in FIG. 4, the torque applying means 30 keeps the total number of the weights 31 a (the total mass of the weights) suspended at both ends of the lever 10 constant (here, 10) while maintaining the torque. The torque applied to the meter 2 is changed. FIG. 4 shows a case where the weights 31a have the same mass. That is, when the torque applied to the torque meter 2 is set to 0 Nm, as shown in FIG.
The number of weights 31a suspended at both ends of the lever 10 is made equal. When torque is applied to the torque meter 2, as shown in FIGS.
The torque applied to the torque meter 2 is adjusted by increasing or decreasing the difference (by changing the suspension position) while keeping the total amount of the weights 31a suspended at both ends of 0 constant.

The control device 50 includes a CPU (Central Processes).
sing Unit), RAM (Random Access Memory), RO
An M (Read Only Memory), an I / O interface, and the like are provided, and various devices connected to the I / O interface are controlled according to a control program and control data written in a ROM. As shown in FIG. 3, the control device 50 is connected to input means such as a CRT 51 and a keyboard which does not appear in the drawing, as well as a servo motor controller 14A, a tilt amplifier 19A, a length measuring device controller 29, and a load cell amplifier 35A. , 35B, a weight adding / removing controller 36, a torque meter amplifier 2A, and the like. Then, the servo motor controller 14
A, the servomotor 14, the tilt amplifier 19 A, the lever tilt sensors 19, 19, the length measuring device controller 29, the measurement receivers 28, 28, and the load cell amplifier 35.
A, 35B are connected to the load cells 35,..., The weight switching controller 33 is connected to the weight switching motor 33a, the torque range switching motor 33b and the rotary encoder 34, and the torque meter amplifier 2A is connected to the torque meter 2. I have.

The control device 50 includes a weight adding / removing controller 36 for applying a desired torque to the torque meter 2.
Control the torque applying means 30 via That is, input from input means such as a keyboard or the load cell amplifier 35
.. Are driven through the load cells 35,... Via the load cells 35,. And by driving the torque range switching motor 33b, the table 32
Is adjusted to adjust the quantity of the weights 31 a suspended from the lever 10 to control the torque applied to the torque meter 2.
At this time, the control device 50 adds to the torque meter 2 by increasing or decreasing the difference (by changing the suspension position) while keeping the total number of the weights 31a suspended at both ends of the lever 10 constant. Change the applied torque. When torque is applied to the torque meter 2, the control device 50 detects the tilt state of the lever 10 based on input signals and the like input from the lever tilt sensors 19, 19 via the tilt sensor amplifier 19A, and In order to hold the lever 10 horizontally with respect to the ground based on this detection,
The drive of the servomotor 14 is controlled via the servomotor controller 14A. Then, the control device 50 obtains the horizontal length of the lever 10 (a state in which deflection occurs) based on input signals and the like input from the measurement receivers 28 via the length measuring device controller 29, and the like. ,
Due to the relationship between the horizontal length of the lever 10 and the load (the difference between the weights 31a suspended at both ends of the lever 10) applied to the lever 10 by the torque applying means 30, the torque is added to the torque meter 2. Calculate the current torque value. Then, a torque value (torque reference value) serving as the reference and a torque value (measured torque value) output from the torque meter 2 via the torque meter amplifier 2A are used.
Calibration of.

According to the torque calibrating device 1 of this embodiment, the torque adding means 30 keeps the total number of the weights 31a suspended on the lever 10 (total mass of the weights) constant.
Since the torque applied to the torque meter 2 is changed by changing the suspension position of the weight 31a, the magnitude of the vertical force acting on the bearing 12 supporting the support shaft 11 of the lever 10, and The magnitude of the frictional force acting in the rotation direction of the lever 10 becomes constant regardless of the magnitude of the torque applied to the torque meter 2. as a result,
Variations in accuracy due to the magnitude of the torque applied to the torque meter 2 can be reduced, and the error due to the frictional force becomes constant, so that correction for the frictional force becomes easy. Thereby, the calibration accuracy of the torque meter 2 can be improved.

[0018]

According to the first aspect of the present invention, the torque applying means changes the suspension position of the weight while maintaining the total mass of the weight suspended from the lever constant, thereby providing a torque meter. The magnitude of the vertical force acting on the lever support and the magnitude of the frictional force acting in the direction of rotation of the lever depend on the magnitude of the torque applied to the torque meter. Constant regardless of As a result, variations in accuracy due to the magnitude of the torque applied to the torque meter can be reduced, and errors due to the frictional force become constant, so that correction for the frictional force becomes easy. Thereby, it becomes possible to improve the calibration accuracy of the torque meter.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a torque calibration device according to the present invention.

FIG. 2 is a perspective view showing the vicinity of a torque meter mounting portion of the torque calibration device of FIG.

FIG. 3 is a block diagram showing a control device constituting the torque calibration device of FIG. 1 and various electric devices connected to the control device.

FIG. 4 is a diagram illustrating a method of adding a weight to a lever of the torque calibration device of FIG. 1;

FIG. 5 is a diagram illustrating a method of adding a weight to a lever of a torque calibrating device according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Torque calibration apparatus 1A Main body frame 2 Torque meter 10 Lever 11 Support shaft 12 Bearing (lever support part) 30 Torque adding means 31a Weight 31 Weight group 50 Control device

Claims (1)

[Claims] 1. A lever connected to a measurement shaft of a torque meter to be calibrated and rotatable integrally with the measurement shaft; a lever support portion rotatably supporting the lever; and a weight attached to the lever. And a torque adding device capable of applying a torque to the torque meter by suspending the lever. The torque adding device maintains a total mass of a weight suspended by the lever constant. A torque calibrating device, wherein a torque applied to the torque meter is changed by changing a hanging position of the weight while keeping the weight.