JPS5812181B2 - tension control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tension control device used in the process of processing or processing a long object such as a plate or wire by moving it while controlling the tension to a constant level.

Conventionally, the most commonly used tension control device with a weight type tension mechanism is as shown in FIG. 6 through the take-up reel 7
During this time, the processing or processing device 8 performs various processing or processing, and the moving speed of the long object 10 is controlled by the motor 12 that drives the take-up reel 7 via the reduction gear 11
The tension is maintained constant by being controlled by a system of a finger speed generator 16 connected to the guide wheel 6, an amplifier 15, and a controller 14, and the tension is controlled by a tension detection system consisting of a tension wheel 4, a weight 5, and a variable resistor 20. The actual tension of the long object 10 detected by the device is applied to the brake 17 via the signal amplifier 19 and the controller 18, and the braking force is changed to make it constant.

Reference numeral 13 denotes a brake connected to the drive motor 12, which is released when the motor 12 is in operation and is in a braking state when the motor 12 is stopped. 5 from falling.

Variations in the tension of the elongate object 10, detected by the position of the tension wheel 4 and thus the output voltage of the variable resistor 20, are primarily caused by variations in the moving speed of the elongate object.

For example, at startup, the motor 12 starts and the take-up reel 7
This causes the elongated object 10 to be pulled out from the delivery reel 1 and to start moving. It is necessary to overcome these forces and accelerate them, which requires a large acceleration torque, but this must be supplied in the form of tension from the winding side through the long object 10, and the tension must be excessive. .

The more rapidly the activation is performed, the greater the tension becomes, and the tension wheel 4 rises rapidly together with the weight 5 and collides with the stopper, possibly leading to an accident in which the long object 10 is cut.

If the weight of the weight 5 is small, the above-mentioned problems such as sudden acceleration and collision of the tension wheel during sudden acceleration can be avoided, and the delivery reel 1 will also start rotating immediately, but this will prevent the long object 10 from being rotated. The applied tension becomes large and the appropriate tension cannot be maintained.

The present invention aims to eliminate the above-mentioned defects and provide a device that can maintain a constant tension in response to any steep fluctuations in winding speed, including acceleration and deceleration. Shown below.

In FIG. 2, the same parts as in FIG. 1 are denoted by the same reference numerals, and as is clear from a comparison with FIG. 1, a drive motor 21 is provided on the delivery reel 1 side in FIG. .

In addition, brakes 22.2 are attached to each reel 1, 1 for sending out and winding up.
3 is installed.

These brakes are constantly operating (generating braking force) not only when the reels 1 and 1 are stopped, but also when they are running, and can be of any type, but disc type or band type are most suitable. Examples include:

The braking force generated by the brakes 22, 23 is the same and is selected more than the tension applied to the elongated object 10, and the motor 2L12 overcomes this braking force and rotates the reels 1, 7.

Therefore, if the motors 21, 12 are de-energized, the brake 22.2
3 immediately brakes and stops the reels 1, 1 and morks 21, 12.

To explain the operation, motors 21 and 12 are simultaneously energized and activated.

As a result, the reels 1, 1 start rotating, and the elongated object 10 is let out from the delivery reel 1, transported in the direction of the arrow, and taken up on the take-up reel 7.

The moving speed of the elongated object 10 is detected by a finger speed motor 16 connected to the guide wheel 6, and is maintained constant by being fed back to the motor 12 via an amplifier 15 and a controller 14.

The tension is detected at the position of the wheel 4 and fed back negatively to the motor 21 through a variable resistor 20 (of course, this can be any suitable element that generates a voltage, generally speaking an electrical signal), an amplifier 19 and a controller 18. to maintain a constant value.

For example, when the tension becomes large, the tension wheel 4 rises, the output voltage of the variable resistor 20 becomes large, the drive torque output by the motor 21 becomes large, and the elongated object 10 is actively fed out to reduce the tension.

Moreover, when the tension becomes small, the tension wheel 4 descends, and as a result, the output dynamic pressure of the variable resistor 20 becomes small, and the motor 21
The output drive torque becomes small, and the feeding of the long object 10 is stopped, or the braking force of the brake 22 becomes dominant and the brake is applied to increase the tension.

The delivery reel 1 has the braking force of a brake 22 and a motor 21.
, and the difference in driving force or braking force is actually applied to the reel.

The driving force of is changed according to the tension.

If this results in excessive tension as at startup, motor 2
The driving force of reel 1 is increased and the reel 1 receives the driving force, and the elongated object 10 is actively fed out to maintain the tension at the set value.

Therefore, the occurrence of the tension wheel 4 and the weight 5 suddenly rising and colliding with the stopper can be avoided.

In addition, during sudden deceleration, the reel 1, etc. continues to rotate due to inertia, and the elongated object 10 is fed out to reduce the tension, causing the tension wheel 4 and the weight 5 to collide with the lower limit stopper, but in this case, the motor 21 The driving force of the reel 1 suddenly decreases, and the braking force of the brake 22 acts on the reel 1 to rapidly decelerate it, thereby preventing the above-mentioned situation from occurring.

In this way, when this device is started, the take-up reel 1 and the delivery reel 1 are rotated by the driving force of the motor 21, and the tension applied to the long object 10 is maintained at the value set by the variable resistor 20. I can do it.

This tension maintenance is of course carried out by adjusting the driving force of the motor 21 during operation, and also when stopped.

That is, when stopping, it is sufficient to simply de-energize the motors 21 and 12 at the same time, and at this time, the reels 1 and 7 are decelerated and stopped by the braking force of the brakes 22 and 23 while maintaining the tension substantially in the operating state.

The present invention was implemented in a length measuring device for wire rods.

When the braking force is 120 kg for a tension of 100 kg, the braking time from the de-energization of the motor to a complete stop is approximately 3 seconds, and during this time the tension wheel 4 remains between the upper and lower limit stoppers, causing a collision. There was no.

As shown in FIG. 3, the length measuring device connects a pulse writing magnetic head 31 and a pulse reading head 32 to a wire 1 with a fixed length L between them.
The head 31 writes pulses, the head 32 reads them, and the controllers 34 and 33 immediately write the pulses.
The head 31 is driven through the wire rod 10 to write pulses again on the wire rod 10, and this process is repeated thereafter.

In this way, the length l of the wire passing through the head 31 can be measured from the number N of read pulses and the distance L (l=N
L) Can be done.

In this case, if the wire tension is too low and sagging occurs within section L, or if the tension is too high and elongation occurs, both of these will result in measurement errors, so it is necessary to keep the tension constant within a predetermined range. be.

Needless to say in detail, there are many cases where constant tension is required in the processing and treatment processes of wire rods and strips, and the present invention is extremely effective when applied to these cases.

As mentioned above, the brakes 22 and 23 may be of a disc type, a band type, or any other type, and an outline of a disc type brake is shown in FIG.

In this figure, 41 is the rotating shaft 42, 43 is the coupling, and 44
is a disc, 45.46, 47.48 are brake pads, and 49, 50, 51.52 are bellows.

When air is forced into the bellows 49-52, the brake pads 45-48 are pressed against the disc 44, producing a braking force.

Normally, air at a constant pressure is introduced into the bellows 49-52.

This device initially sets the braking force to a predetermined value and does not change it during operation.

The brake 22 on the delivery reel 1 side is necessary because this system is an inertial load and the speed cannot settle to a predetermined value with N current, but on the take-up reel 7 side, the resistance component of the load is Since the processing apparatus 8 is large, especially when the processing apparatus 8 is a die of a wire drawing apparatus, the brake 23 of a type that generates braking force even during operation is not necessarily required.

Since it is necessary to prevent the reel 1 from reversing while it is stopped, a normal electromagnetic brake 1 that operates at the same time as the motor is de-energized is used.
3 should be provided instead of the brake 23.

As explained in detail above, according to the present invention, a tension control device with high responsiveness can be obtained, the tension of a long material can always be maintained at a desired value, and the device cost is low. .

[Brief explanation of drawings]

Figure 1 is a wiring diagram showing the configuration of a conventional tension control device;
The figure is a wiring diagram showing an embodiment of the present invention, FIG. 3 is an explanatory diagram of a length measuring device, and FIG. 4 is an explanatory diagram of the main structure of a disc brake. In the drawing, 10 is a long object, 1 is a delivery reel, 8 is a processing device, 7 is a take-up reel, 22 and 23 are brakes, and 21
is the motor.

Claims (1)

[Claims] 1. A brake that constantly generates a braking force greater than the tension on the delivery reel in a tension control device for a long object of a device that unwinds the long object from the delivery reel and winds it onto the take-up reel via the processing device; It is characterized by being connected to a motor capable of generating a driving force greater than the braking force and controlling the generated driving force to a constant level by adjusting the generated driving force according to fluctuations in the detected tension of the long object. tension control device.