JPH0562937B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a torque detection method for detecting the torque of a motor or the like, and particularly to a torque detection method with excellent torque responsiveness.

[Prior Art] Conventionally, as a torque detection device for detecting the torque of a motor or the like, the one shown in FIG. 5 is known.

In FIG. 5, for example, the motor whose torque is to be measured is connected to a shaft 61 to which a drum 60 is attached, and when a load is applied to the drum 60 by a load mechanism 62, the torque of the motor is measured. .

To explain the load mechanism 62, the gear motor 6
3 is connected to a threaded rod 64, and this threaded rod 6
4 causes the bracket 66 to which the nut 65 is attached to stroke back and forth. The pin 6 embedded in the notch of this bracket 66
7 and 68 are inserted into elongated holes 73 and 74 of arms 71 and 72 which are supported by support shafts 69 and 70, so that the stroke movement of bracket 66 is caused by the movement of arms 71 and 7.
It can be changed to the lever movement of 2. Also arm 71,
72 has crimp pins 75 and 76 attached to it, and by levering the arms 71 and 72, the support shaft 7
Brake lining 79 supported by 7, 78,
80 is pressed against the drum 60 side with a strong force. The pressure applied to the drum 60 applies a load to the motor whose torque is measured.

The other end of a coil spring (not shown) whose one end is fixed to the housing is attached to the bracket 66, and when a pressing force is applied to the drum 66, the entire load mechanism 62 rotates by reaction until it is in equilibrium with the coil spring. do. Torque is measured by detecting this rotation with an angle sensor such as a magnetic potentiometer and converting a voltage proportional to torque through an electric circuit.

[Problems to be Solved by the Invention] By the way, in the above-described torque detection device, the entire load mechanism 62 is controlled by a coil spring, and the inertia seen from the motor whose torque is detected is large, resulting in a poor torque response. There is a problem that it is bad.
Particularly when trying to detect the torque of a stepping motor, if the inertia is large, the motor cannot follow the drive pulse signal and the motor loses synchronization, causing a problem that the torque cannot be detected accurately.

Furthermore, the load mechanism 62 has a problem in that the transmission path of the force that applies the pressing force to the drum 60 is long, making it impossible to smoothly apply the load to the motor.

Further, in the load mechanism 62, there is a loss of force in the transmission path, so when changing the load, a delay occurs in the transmission time, resulting in a problem of poor load response.

The present invention has been proposed to solve these conventional problems, and provides a detection method with good torque responsiveness that can reduce the inertia seen from the motor whose torque is detected. The purpose is to

[Means for solving the problem] In order to achieve this object, the torque detection method of the present invention supports one end on the drum surface of a drum that is connected to the rotating shaft of the rotating machine to be detected and rotates, By moving the leaf spring with the brake lining attached to the other end in a direction perpendicular to the drum surface, the brake lining is pressed horizontally against the drum surface, and the connection direction of the drum is moved between the drum surface and the brake lining. The torque of the rotating machine to be detected is detected by deflecting the plate spring by the applied force and detecting the amount of deflection of the plate spring by a displacement sensor.

[Function] Therefore, in the method of the present invention, by sliding the leaf spring perpendicularly to the drum surface, the brake lining attached to the leaf spring is pressed horizontally to the drum surface, and the torque generated by the drum rotation causes the brake lining attached to the leaf spring to be pressed horizontally to the drum surface. Since the torque of the rotating machine to be detected, such as a motor, is detected by detecting the amount of deflection of the leaf spring, the load seen from the rotating machine to be detected is reduced, and torque responsiveness is improved.

[Example] Hereinafter, an example of the present invention will be described in detail based on the drawings.

FIG. 1 is a perspective view for explaining a torque detection method according to an embodiment of the present invention, and FIG. 2 is a front view of FIG. 1.

In the figure, a rotating shaft of a rotating machine to be detected, such as a motor whose torque is to be measured, is connected to a connecting shaft 2 on which a drum 1 is attached on a concentric shaft. The drum 1 also has brake linings 7, 8 made of urethane rubber, asbestos, hard carbon, etc. attached to the plate springs 3, 4 via brake holders 5, 6.
A strong crimping force is applied from above and below. The application of this pressure force is carried out at the support point O1 of the leaf springs 3 and 4,
This is done by a screw shaft and gear motor provided on the O2 side. The reason why the leaf springs 3 and 4 are provided on the upper and lower sides is to apply pressing force evenly to the upper and lower sides of the drum 1 to balance the force, and to be able to measure the torque in both rotational directions. .

Here, the diameter of the drum 1 is D, the pressure force (total legal pressure) by the brake linings 7 and 8 is P,
The force acting in the tangential direction on the drum 1 due to the pressing force P is F, the friction coefficient between the drum 1 and the brake linings 7 and 8 is μ, and the torque acting on the drum 1 is T.
Then, the torque T becomes T=F・D=μP・D. From this equation, the diameter D of the drum 1 can be reduced by increasing the pressing force P or increasing the friction coefficient μ. In detecting the torque T, since it is necessary to reduce the inertia seen from the motor side, it is necessary to reduce the diameter D to make the drum 1 as small as possible.

Further, the leaf springs 3 and 4 have a force F acting in the tangential direction.
Therefore, if the spring constant of the leaf springs 3 and 4 is K and the amount of deflection of the leaf springs 3 and 4 is δ, then the amount of deflection δ becomes δ=K·F. From this equation, F=δ/K, and by substituting this into the previous equation, the torque T becomes T=δ/K·D.

Therefore, by detecting the amount of deflection δ of the leaf springs 3 and 4, the torque T of the motor can be measured.

This amount of deflection δ is determined by the displacement sensors 9, 10, such as magnetic displacement sensors, disposed on the sides of the tips of the leaf springs 3, 4.
is detected without contact. In the illustrated example, since the drum 1 is rotating in the right direction, the displacement sensor 10 detects the amount of deflection δ of the leaf spring 4, which is deflected far away from the sensor.

The displacement sensors 9 and 10 are attached to a sensor mounting plate that is fixed via a spacer at the support points O1 and O2 of the leaf springs 3 and 4.

Note that when the brake linings 7, 8 come into pressure contact with the drum 1, the leaf springs 3, 4 undergo rotational displacement around the support points O1, O2, but the length of the leaf springs 3, 4 is determined by the amount of deflection δ. If it is large enough, it can be regarded as a linear displacement.

In this way, the torque detection method of the present invention does not rotate the entire load mechanism 62 as in the conventional case, but only displaces the leaf springs 3 and 4 to which the brake linings 7 and 8 are attached, and the torque is detected. The inertia seen from the motor is small and the torque response is good.

Next, a third example of a mechanism for pressing the plate springs 3 and 4 to which the brake linings 7 and 8 are attached to the drum 1 is shown.
The description will be made with reference to a side view of the figure.

In this example, a drum 1 having a fin structure is attached to a connecting shaft 2 that is pivotally supported by bearings 11 and 12. By forming the drum 1 with a fin structure in this manner, the heat generated by the drum 1 during pressure bonding of the brake linings 7 and 8 can be efficiently dissipated.

The above-mentioned leaf springs 3 and 4 are fixed to the movable rails 15 and 16 side of the linear guide tables 13 and 14, which are composed of a fixed rail and a movable rail. Further, sensor mounting plates 17 and 18 are fixed to the support points of the leaf springs 3 and 4 via spacers, and the above-mentioned displacement sensors 9 and 10 are mounted on the ends of the sensor mounting plates 17 and 18. It is attached perpendicularly to the springs 3 and 4.

Each of the moving rails 15 and 16 is formed with a female thread that is a reverse thread, and a threaded rod 19 is screwed into this female thread. Also, this threaded rod 1
A spur gear 20 is attached to 9, and a pinio gear 22 attached to a drive shaft of a gear motor 21 meshes with this spur gear 20.

Therefore, by driving the gear motor 21, the leaf springs 3 and 4 move toward the drum 1, and the drum 1 is strongly pressed by the brake linings 7 and 8.

By using the linear guide tables 13 and 14 in this manner, the support points of the leaf springs 3 and 4 do not wobble, and even pressure is applied to the top and bottom of the drum 1.

In addition, the force is doubled by the gear motor 21 and the screw jack to apply the crimping force to the drum 1, but the gap between the brake linings 7, 8 and the drum 1 can be set narrowly, and the amount of displacement in the direction of the drum 1 after crimping is Since it is extremely small, the gear motor 21,
Furthermore, the gear ratio of the spur gear 20 and pinion gear 22 and the thread pitch of the threaded rod 19 can be set to further increase the pressing force.

Further, since the leaf springs 3 and 4 move up and down in parallel with the sensor mounting plates 17 and 18, only the rotational torque component can be detected without introducing noise components.

In addition, the conventional torque measurement time (scan time) was approximately one minute, but in the above-mentioned mechanism, the rotation of the gear motor 21 is directly transmitted to the threaded rod 19, and the brake lining 7, which presses the drum 1,
8, the torque measurement time is shortened to about 5 seconds.

Next, a circuit for converting the sensor output from the displacement sensors 9 and 10 into a voltage proportional to torque will be explained based on FIG. 4.

In FIG. 4, the output from the displacement sensor 9 or 10 is amplified by a dedicated amplifier 25, and converted into a voltage proportional to torque by an operational amplifier 26 at the subsequent stage.
Then, a torque detection signal is output from the output terminal 27. The variable resistor 28 is for zero point adjustment.

Note that the present invention can also be applied to detecting the torque of a rotating machine to be tested, such as an internal heat engine, in addition to motors.

[Effects of the Invention] As described above, in the present invention, a plate spring to which a brake lining is attached is crimped onto a drum, and the amount of deflection of the plate spring is detected in a non-contact manner by a displacement sensor to measure torque.

Therefore, the load seen from the motor whose torque is detected is reduced, and torque responsiveness is improved.
Particularly, when the torque detection device of the present invention is used to detect the torque of a stepping motor, the torque can be detected satisfactorily without causing step-out.

[Brief explanation of the drawing]

FIG. 1 is a perspective view for explaining a torque detection method according to an embodiment of the present invention, FIG. 2 is a front view of FIG. 1, and FIG. 3 is a side view for explaining a leaf spring crimping mechanism. FIG. 4 is a circuit diagram for processing a sensor output signal of a displacement sensor, and FIG. 5 is a perspective view of a conventional torque detection device. 1... Drum, 2... Connection shaft, 3, 4... Leaf spring, 5, 6... Brake holder, 7, 8... Brake lining, 9, 10... Displacement sensor, 1
3, 14...Linear guide table, 15, 16
...Movement rail, 17, 18...After sensor installation,
19... Threaded rod, 20... Spur gear, 21... Gear motor, 22... Pinion gear, 25... Dedicated amplifier, 26... Operational amplifier, 27... Output terminal.

Claims (1)

[Claims] 1. Moving a leaf spring, which is supported at one end and has a brake lining attached to the other end, in a direction perpendicular to the drum surface of a drum that rotates while being connected to the rotating shaft of the rotating machine to be detected. The brake lining is pressed horizontally against the drum surface, and the leaf spring is deflected by the force acting in the tangential direction of the drum between the drum surface and the brake lining,
A torque detection method characterized in that the torque of the rotating machine to be detected is detected by detecting the amount of deflection of the leaf spring using a displacement sensor.