JP2000258265A - Torque measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure torque at a specified number of rotation without giving excessive load to a device by arranging a turbine provided with a wind pressure receiving part to an output shaft of a rotating device to be measured, and introducing airflow to give a load in the constitution. SOLUTION: A torque measuring device of a micromotor 5, etc., for a portable intelligent terminal, etc., is provided with a turbine 8 with a blade 8a to be fitted to an output shaft 5 of the motor 5, a pressure sensor 16, an optical sensor 12 for detecting the number of rotation of the turbine 8, and a frequency counter 13. The motor 5 is turned at a specified number of rotation, an airflow generating means such as a cleaner 17, etc., is activated, and an air sucked from a suction inlet 9a is allowed to be hitted to the blade 8a. The blade 8a hit by the air, works on the motor 5 as a load, and the load value is obtained by multiplying a differential pressure between an outlet-side chamber and the outside air with an area of the blade 8a. A torque can be obtained from a measured value of the pressure sensor 16 at the time when the output of the frequency counter 13 is reduced as the output of the cleaner 17 is increased gradually.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque measuring device suitable for detecting a torque of a minute rotating device such as a micro motor used for a portable terminal or a portable telephone.

[0002]

2. Description of the Related Art FIG. 6 is a block diagram of a torque measuring device disclosed in Japanese Patent Application Laid-Open No. Sho 59-142429. This torque measuring device includes a rotating part 10 attached to a motor 101.
2 comes into contact with a terminal 104 attached to the hairspring 103. The hairspring 103 is held by a frame 105 and is entirely formed of a pair of receiving members 10.
6 supported. Then, when the motor 101 rotates, the hairspring 103 is wound via the rotating portion 102 and the terminal 104.

In this torque measuring device, the hairspring 103 is wound as the motor 101 rotates, and the force generated on the hairspring 103 gradually increases. When the force of the hairspring 103 becomes equal to the rotation torque of the rotating portion 102 of the motor 101, the rotation of the motor 101 stops. Then, the torque is calculated by detecting the rotation angle from the initial position when the rotating portion 102 of the motor 101 is brought into contact with the terminal 104 to the position where the rotation of the motor 101 is stopped by the sensor 107.

[0004]

At present, in consumer appliances, portable terminals, portable telephones, etc., the thickness and weight of the appliances have been promoted, and the motors to be used have been miniaturized. From the viewpoint of reducing power consumption of equipment, securing efficiency, and improving reliability,
It is important to develop a method for measuring the torque of a motor. However, the above-described conventional torque measuring device has a problem that it is difficult to measure the torque when the rotation angle is large because the amount of winding of the hairspring 103 is limited.

In addition, since it is necessary to attach the rotating part 102 to the motor 101, when the torque of the motor 101 is small, the rotating part 102 becomes a load, making it difficult to accurately measure the torque or miniature size. In the case of the motor described above, there is also a problem that it is difficult to attach the rotating part 102 to the rotating shaft of the motor 101.

Further, when the center of the hairspring 103 does not coincide with the axis of the motor 101, the motor 1
Since the torque of the hairspring 103 acts obliquely with respect to the axis 01, there is also a problem that the measurement accuracy is poor.

Further, a motor 101 and a mainspring 10 are provided.
3 is a rotating part 102 extending in the radial direction and a terminal 10
4, the eccentric load acts on the motor 101, resulting in poor measurement accuracy.

Further, it is difficult to continuously measure the torque when the motor 101 is rotating.
In order to perform torque measurement over a rotation speed of tens of thousands of rpm or more, it is necessary to prepare a plurality of types of hairsprings 103 with different spring constants, and there is a problem that the measurement takes time.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a torque measuring device capable of easily and accurately measuring a torque. Is what you do.

[0010]

According to a first aspect of the present invention, there is provided a torque measuring device having a wind pressure receiving portion attached to an output shaft of a rotating device to measure a torque and receiving a wind pressure of an airflow. A central hole in which the air flow that applies a load to the turbine is introduced into the central hole from the suction port opened on the inner peripheral surface of the central hole, and the introduced air flow is directed in the axial direction of the turbine from the opening of the central hole. An annular guide plate for exhausting and discharging, an airflow generating means for generating an airflow which is introduced from the suction port and collides with the wind pressure receiving portion, and an airflow adjusting means for adjusting an airflow generated by the airflow generating means, A wind pressure detecting means for detecting a wind pressure acting on the wind pressure receiving portion; and a rotation speed detecting means for detecting a rotation speed of the turbine, wherein the output shaft is rotated at a predetermined rotation speed, and The air flow generated by the generating means is increased by the air flow adjusting means, the wind pressure at which air collides with the wind pressure receiving part is increased, and the wind pressure acting on the wind pressure receiving part at the time when the rotation speed of the output shaft is reduced Is detected by the wind pressure detecting means, and the torque of the output shaft at a predetermined rotation speed is measured.

[0011] In the torque measuring device according to the second aspect, the wind pressure detecting means is a pressure sensor for measuring the pressure of the airflow discharged from the opening of the guide plate, and the value of the pressure of the pressure sensor and the outside air are measured. The wind pressure acting on the wind pressure receiving portion is detected based on the pressure difference.

In the torque measuring device according to the third aspect, the wind pressure receiving portion is at least two blades extending in the radial direction and attached to the outer peripheral portion of the turbine.

In the torque measuring device according to a fourth aspect, the number of suction ports corresponding to the number of the plurality of blades is respectively formed in the tangential direction of the turbine.

In the torque measuring device according to the fifth aspect, the blades are arranged to face each other.

[0015] In the torque measuring device according to claim 6, the rotating device is a motor.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a configuration diagram of a torque measuring device according to Embodiment 1 of the present invention.
The torque measuring device is provided with a turbine 8 which is attached to an output shaft 5a of a motor 5 as a rotating device for which torque is to be measured and has a blade 8a as a wind pressure receiving portion for receiving wind pressure of an air flow, and the turbine 8 is arranged. Central hole 9
b, and a suction port 9a opened in the inner peripheral surface of the central hole 9b.
And an annular guide plate 9 for introducing an airflow that applies a load to the turbine 8 into the central hole 9b and discharging the introduced airflow from the opening of the central hole 9b on the opposite side to the motor 5 in the axial direction of the turbine 8. A cleaner 17 as an airflow generating means for generating an airflow introduced from the suction port 9a of the guide plate 9, and a slide pack 1 as an airflow adjusting means for adjusting the airflow.
8, a pressure sensor 16 for detecting a wind pressure acting on the blade 8a, an optical sensor 12 as a rotation speed detecting means for detecting a rotation speed of the turbine 8, and a frequency counter 1
3 is provided.

FIG. 2 shows a turbine 8 of the torque measuring device of FIG.
FIG. The turbine 8 has a disk shape and is provided with plate-like blades 8a extending in a radial direction. On the other hand, the guide plate 9 has a disk shape having a central hole 9b surrounding the entire turbine 8 including the blades 5, and the central hole 9b
Hole diameter is slightly larger than the outer diameter of the turbine 8 and the suction port 9
a penetrates from the inner peripheral side to the outer peripheral side of the guide plate 9 in a direction orthogonal to the rotation axis of the turbine 8.

The motor 5 is housed in a motor-side chamber 11. The motor-side chamber 11 is connected to the outlet-side chamber 15 via the guide plate 9. The motor 5 in the motor-side chamber 11 is supported by a motor stage 10 so that its position can be adjusted. Outlet side chamber 1
The optical sensor 12 in 5 is positionally supported by a sensor stage 14 and connected to a frequency counter 13 outside the outlet chamber 15 by a lead wire. The outlet chamber 15 is connected to the outlet chamber 15 through a ventilation passage 15a. Thus, the cleaner 17 is connected, and the cleaner 17 sucks air in the outlet side chamber 15. The output of the cleaner 17 can be adjusted by a slide rack 18. The pressure of the airflow discharged from the central hole 9b of the actual inner plate 9 to the outlet side chamber 15 is measured by a pressure sensor 16.

This torque measuring device measures the torque of the motor 5 according to the following procedure. First, the turbine 8 is fixed to the output shaft 5a of the motor 5. Next, the motor 5 to which the turbine 8 is attached is fixed to the motor stage 10 and disposed in the motor-side chamber 11. Then, the turbine 8
The motor stage 11 is adjusted so that is positioned at the center of the guide plate 9.

On the other hand, an optical sensor 12 for measuring the number of revolutions of the motor 5 is fixed to a sensor stage 14 and disposed in an outlet side chamber 15. Next, the sensor stage 14 is adjusted so that the optical sensor 12 is located on the outer periphery of the blade 8 a of the turbine 8. At this time, while rotating the motor 5, the height of the sensor stage 14 is adjusted so that the output of the optical sensor 12 is maximized. Optical sensor 12
Is usually used for measuring the displacement between the tip of the sensor fiber and the object, and a pulse-like output is obtained when the blade 8a of the turbine 8 passes through the optical sensor 12. The frequency of this output waveform is By measuring with the counter 13, the number of rotations of the motor 5 can be obtained. After arranging the motor 5 and the sensors as described above, the rotational torque of the motor 5 is measured.

First, the motor 5 is rotated at a predetermined rotation speed. Next, the cleaner 17 is rotated by gradually increasing the voltage of the slide rack 18. By activating the cleaner 17, the air around the torque measuring device is changed as shown in FIG.
As shown by the arrow A in the middle, the cleaner 17 passes through the outlet side chamber 15 from the suction port 9a provided in the guide plate 9, and
To the exit side of

When the output of the cleaner 17 is increased by gradually increasing the voltage of the slide rack 18, the flow velocity of the air increases, and the blade 8 a of the turbine 8 passes through the suction port 9 a as shown by an arrow B in FIG. (B)
As described above, the air flowing from the suction port 9a collides with the blades 8a of the turbine 8 and flows out to the outlet side chamber 15 along the axial direction of the turbine 8 as shown by an arrow C. The rotation speed of the motor 5 at this time is monitored by the frequency counter 13.

The blade 8a collides with air,
It receives a force corresponding to the pressure difference between the outlet side chamber 15 and the atmosphere, and acts as a load on the motor 5. The value of the load acting on the motor 5 can be determined by multiplying the pressure difference between the inside of the outlet side chamber 15 and the atmosphere by the area of the blade 8a. The force applied to the turbine 8 increases due to the increase in the air flow, and accordingly, the rotation speed of the motor 5 decreases stepwise.

While checking the output of the frequency counter 13, the output of the cleaner 17 is gradually increased, and the value of the pressure sensor 16 when the output of the frequency counter 13 decreases is measured. From this pressure value, the motor 5
, And multiplying the average radius of the blades 8a of the turbine 8 by the measured load amount, the torque at that time during rotation at a predetermined rotation speed can be obtained. Further, the number of rotations of the motor 5 is changed,
By repeating the above operation, it is possible to measure the torque of the motor 5 at a new rotation speed.

As described above, in this torque measuring device,
By applying the wind pressure to the turbine 8, the torque of the motor 5 can be measured, and the torque during rotation can be measured for an arbitrary number of rotations of the motor 5. Further, since the load acting on the motor 5 is only air, no extra load is applied to the motor 5 and the measurement accuracy can be improved. Further, the turbine 8 is connected to the output shaft 5 a of the motor 5. Since the torque can be measured only by mounting, the time required for the measurement can be reduced.

Embodiment 2 FIG. Next, another embodiment of the present invention will be described. In the following description, points different from the first embodiment will be described, and the same or equivalent members as those in the first embodiment will be denoted by the same reference numerals. FIG. 3 is a cross-sectional view showing a cross section of a planar shape of a suction port 9a of a guide plate 9 in the torque measuring device according to the second embodiment. The turbine 8 has two blades 8a and a central portion of the turbine 8a. Has a structure that does not receive wind pressure. For example, when the torque of the motor 5 is very small and the strength of the motor 5 itself is also small, if the area of the blade 8a is too large, an excessive load acts on the bearing of the motor 5 and the bearing may be damaged. is there. For this reason, if the flow of air is not cut off at the center of the turbine 8 as in this embodiment,
The torque can be measured without damaging the motor 5.

Embodiment 3 FIG. 4 is a cross-sectional view showing a cross section of the planar shape of the suction port 9a of the guide plate 9 in the torque measuring device according to the third embodiment, and two blades 8a are provided for the turbine 8 and the blades 8a are provided. And the suction port 9a of the guide plate 9 is formed in the tangential direction of the turbine 8. In this torque measuring device, the blades 8a receiving the wind pressure are less likely to disturb the air flow, the air flow is stabilized, and the measurement resolution and measurement accuracy can be improved. Further, since two blades 8a and two suction ports 9a are provided, when the blades 8a receive wind pressure,
Since the load acting on the bearing of the motor 5 due to the couple acting on the motor 5 is canceled, no extra load acts on the bearing, and the measurement accuracy can be further improved. Further, even when the motor 5 is ultra-small and the structural strength itself is small, the possibility that the bearings of the motor 5 are damaged by an excessive load is reduced.

Embodiment 4 FIG. 5 is a cross-sectional view showing a cross section of the planar shape of the suction port 9a of the guide plate 9 in the torque measuring device according to the fourth embodiment. And four suction ports 9a of the guide plate 9 are formed in the tangential direction of the turbine 8 in substantially the same area as the blades 8a. In this torque measuring device, the blade 8a receiving the wind pressure disturbs the air flow further less than in the third embodiment, the air flow is further stabilized, and the measurement resolution and the measurement accuracy are further improved. be able to. Further, since four blades 8a and four suction ports 9a are provided, when the blades 8a receive wind pressure, a couple acts on the motor 5 to cancel the load acting on the bearings of the motor 5. Therefore, no extra load acts on the bearing, and the measurement accuracy can be further improved. Also, the motor 5 is very small,
Even when the structural strength itself is low, the possibility that the bearings of the motor 5 are damaged by an excessive load is further reduced.

[0029]

As described above, according to the first aspect of the present invention, the airflow generated by the airflow generating means is increased by the airflow adjusting means while the output shaft is rotated at a predetermined rotation speed. To increase the wind pressure at which the air collides with the wind pressure receiver,
Since the wind pressure acting on the wind pressure receiving portion at the time when the rotation speed of the output shaft decreases is detected by the wind pressure detection means, and the torque of the output shaft at a predetermined rotation speed is measured, the rotation device The torque during rotation can be measured without applying an extra load. Further, the torque during rotation at an arbitrary rotation speed can be measured by changing the rotation speed of the output shaft of the rotating device. Furthermore, since the torque of the rotating device can be measured only by attaching the rotating device to the turbine, the measurement period can be shortened.

According to the second aspect of the present invention, the wind pressure detecting means is a pressure sensor for measuring the pressure of the airflow discharged from the opening of the guide plate. Since the pressure difference acting on the wind pressure receiving portion is detected based on the pressure difference between the wind pressure receiving portion and the air pressure receiving portion, the wind pressure acting on the wind pressure receiving portion can be easily detected.

According to the third aspect of the present invention, since the wind pressure receiving portion is at least two blades extending in the radial direction and attached to the outer peripheral portion of the turbine, the flow of air at the central portion of the turbine is improved. Is not interrupted. For example, even when the torque of the motor is very small and the strength of the motor itself is also small, an excessive load does not act on the bearing of the motor, so that damage to the bearing can be prevented.

According to the fourth aspect of the present invention, since the number of suction ports corresponding to the number of the plurality of blades is formed in the tangential direction of the turbine, the flow of air is stabilized and the measurement is performed. Resolution and measurement accuracy can be improved.

According to the fifth aspect of the present invention, since the blades are arranged to face each other, a couple acts on the output shaft of the rotating device when the blades receive wind pressure. For example, since the load acting on the bearing of the motor is canceled, no extra load acts on the bearing, and the measurement accuracy is improved.

According to the invention, since the rotating device is a motor, the torque of the motor can be easily measured.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a torque measuring device according to Embodiment 1 of the present invention.

2A is a plan view showing a cross section of a plane shape of a suction port of the guide plate of FIG. 1, and FIG. 2B is a simplified view of left and right suction ports of the guide plate of FIG. It is sectional drawing.

FIG. 3 is a plan view showing a cross section of a planar shape of a suction port of a guide plate of the torque measuring device according to the second embodiment of the present invention.

FIG. 4 is a plan view showing a cross section of a planar shape of a suction port of a guide plate of a torque measuring device according to Embodiment 3 of the present invention.

FIG. 5 is a plan view showing a cross section of a planar shape of a suction port of a guide plate of a torque measuring device according to Embodiment 4 of the present invention.

6A and 6B show a conventional torque measuring device for a micromotor. FIG. 6A is a plan sectional view of a main part, and FIG. 6B is a longitudinal sectional view.

[Explanation of symbols]

5 motors (rotating equipment), 5a output shaft, 8 turbines, 8a
Blades, 9 guide plates, 9a suction port, 12 optical sensors (rotational speed detecting means), 13 frequency counters (rotating speed detecting means), 1
6 pressure sensors (wind pressure detecting means), 17 cleaners (air flow generating means), 18 slydacs (air flow adjusting means).

Claims (6)

[Claims] 1. A turbine having a wind pressure receiving portion attached to an output shaft of a rotating device for which torque is to be measured and receiving a wind pressure of an air flow, a center hole in which the turbine is disposed, and an opening in an inner peripheral surface of the center hole. An annular guide plate that introduces an airflow that applies a load to the turbine from the suction hole into the central hole, and discharges the introduced airflow from the opening of the central hole in the axial direction of the turbine; Airflow generating means for generating an airflow that collides with the wind pressure receiving portion; airflow adjusting means for adjusting an airflow generated by the airflow generating means; wind pressure detecting means for detecting a wind pressure acting on the wind pressure receiving portion; Rotation speed detection means for detecting the rotation speed of the turbine, and in a state where the output shaft is rotated at a predetermined rotation speed, the airflow generated by the airflow generation means is controlled by the airflow adjustment means. Increase, the wind pressure at which air collides with the wind pressure receiving portion is increased, and the wind pressure acting on the wind pressure receiving portion at the time when the rotation speed of the output shaft decreases is detected by the wind pressure detecting means,
A torque measuring device adapted to measure a torque of an output shaft at a predetermined rotation speed. The wind pressure detecting means is a pressure sensor for measuring a pressure of an airflow discharged from an opening of the guide plate, and a pressure difference between the pressure sensor and the outside air is applied to a wind pressure receiving portion. 2. The torque measuring device according to claim 1, wherein the wind pressure acting on the torque measuring device is detected. 3. The torque measuring device according to claim 1, wherein the wind pressure receiving portion is at least two blades extending in a radial direction and attached to an outer peripheral portion of the turbine. 4. The torque measuring device according to claim 3, wherein a number of suction ports corresponding to the number of the plurality of blades are respectively formed in a tangential direction of the turbine. 5. The blade according to claim 4, wherein the blades are arranged to face each other.
4. The torque measuring device according to claim 1. 6. The torque measuring device according to claim 1, wherein the rotating device is a motor.