JPH07185899A - Driving device for variable punching speed press - Google Patents

Abstract

PURPOSE:To change inertia corresponding to a rotational speed by attaching a weight which is movable in a radial direction in the inside or on the side face of a flywheel and constituting the weight so that the weight approaches the center as the flywheel is revolved at a higher speed and the weight is gone away from the center as the flywheel is revolved at a lower speed. CONSTITUTION:Supporting shafts 23 are horizontally provided between the flywheel 15 and a case 20 leaving a prescribed interval between mutual cocenters. Gears 24 are loosely fitted to the supporting shaft 23 so as to be freely rotatable and engaged with a sun gear 22. Further semicircular guide holes 20a are opened around the supporting shafts 23 on the case 20. On the other hand, pins 25 are projectingly provided on the side face of the gears 24 and passed through the guide holes 20a and the weights 26 are fixed at the tip of the pin. By arranging the respective weights 26 making the positions in the radial direction to coincide and driving a servomotor 21, the sun gear 22 is revolved, the gears 24 are revolved and the weights 26 are constituted so as to be movable in the radial direction along the guide hole 20a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for improving the flywheel in a press machine such as a punch press so that the inertia can be changed according to the rotation speed.

[0002]

2. Description of the Related Art In press machines such as punch presses,
In a mechanical press drive, the energy required for punching is stored as kinetic energy for the rotation of the flywheel, and a clutch is interposed as a means for converting the rotary motion of the crankshaft that supports the flywheel into a linear reciprocating motion. Punching is performed by cutting off and contacting the rotary power from the flywheel. For example, in a punch press machine, a table is arranged on a base, a punch is arranged above the table, a die is arranged below the table so as to face the punch, and a plate material (workpiece) supplied onto the table is placed on the punch and the die. The punch is connected to the crank mechanism via a pitman and a ram, and the punch is lowered to enable punching. A flywheel is connected to the crankshaft, the flywheel is connected to a drive shaft of a motor through a belt, and the crankshaft is rotated by the drive of the motor through the flywheel to raise and lower the ram. Was there.

[0003]

Since the punching speed of the above-mentioned press machine is governed by the rotational speed of the flywheel, if the rotational speed of the flywheel is variable, for example, if the flywheel is rotated at a high rotational speed, the production speed is increased. Can improve
Noise can be kept low by processing at a lower speed. A cam mechanism may be used as the means for changing the rotation speed, but the structure is complicated, and therefore the rotation speed of the motor is usually controlled by a transmission, frequency control, or phase control. However, if the rotation speed of the flywheel is reduced, the kinetic energy of rotation stored in the flywheel becomes smaller. Also, a larger flywheel is required for continuous punching,
It is almost impossible to change the flywheel according to the type of processing. Therefore, the present invention seeks to keep the kinetic energy constant regardless of the number of rotations by moving the weight on the flywheel.

[0004]

The problems to be solved by the present invention are as described above. Next, the means for solving the problems will be described. That is, a weight movable in the radial direction is attached to the inside or the side surface of the flywheel, and the weight is moved closer to the center as the flywheel rotates at higher speed, and the weight is moved away from the center as the wheel rotates at lower speed. is there.

[0005]

[Operation] Next, the operation will be described. When the flywheel configured as above is rotated at high speed, the weight is moved to a position close to the center of the flywheel to reduce the inertia of the flywheel, and when rotating at low speed, the weight is moved to a position far from the center of the flywheel. By increasing the inertia, the rotational kinetic energy of the flywheel is kept constant regardless of the rotational speed.

[0006]

EXAMPLES Next, examples of the present invention will be described. Figure 1
Is a perspective view of a punch press equipped with a variable punching speed press drive device of the present invention, FIG. 2 is a side view of a flywheel, FIG. 3 is a sectional view taken along line XX in FIG. 2 and a control block diagram, and FIG. 4 is punching. 4 is a side view of a flywheel showing another embodiment of the variable speed press drive device, and FIG.
6 is a cross-sectional view taken along line YY in FIG.

Explaining the entire structure of a punch press P as a press machine in FIG. 1, a center table 2 is arranged on the front center of a lower frame 1, and rails 9 and 9 are provided on both sides of the lower frame 1 in the front-rear direction. , The carriage 4 is mounted on the rails 9 and 9 so as to be movable in the front-rear direction, and side tables 3L and 3R are fixed to the carriage 4 on both sides of the center table 2. The side tables 3L and 3R are movable together with the carriage 4 in the front-rear direction. The carriage 4
A cross slide (not shown) is provided in the rear portion so as to be movable in the left-right direction, and a work holder (not shown) is projected rearward of the cross slide so that a work can be gripped.

An upper frame 5 is arranged above the rear portion of the lower frame 1, and an upper turret 6 is rotatably arranged on the upper frame 5, and a plurality of punches are mounted on the upper turret 6 along the circumference. Has been done. On the other hand, a lower turret 7 is rotatably arranged at the rear portion of the center table 2 and a plurality of dies are mounted along the outer periphery so as to face the punches, and the upper turret 6 and the lower turret 7 are simultaneously rotated. By selecting a desired die and punch, the work is positioned between the die and the punch, and the work can be processed by moving up and down the ram 10 arranged on the front part of the upper turret 6.

A motor 11 is provided in the upper frame 5 to move the ram 10 up and down.
The power is transmitted from the pulley 12 fixed to the drive shaft of the vehicle through the belt 13 to the flywheel 15 which is externally fitted to one end of the crankshaft 14 which is laid horizontally on the upper frame 5, and the flywheel 15 through the clutch. By rotating the crankshaft 14, the pitman 1 can be freely rotated on the crankshaft 14.
6 is pivoted to convert the rotary motion into the reciprocating motion of the pitman 16, and the ram 10 is attached to the lower end of the pitman 16,
The lower end of the ram 10 is engaged with the punch to enable punching. However, the rotation speed of the motor 11 can be changed by changing the frequency, voltage, etc., but it is also possible to connect a transmission to the output shaft of the motor and change the speed by a signal from the control circuit.

In such a turret punch press P, the flywheel 15 which is the main part of the present invention and its control structure will be described with reference to FIGS.
The belt groove is formed on the outer circumference so that the belt 13 can be wound and rotated, and power can be transmitted to the crankshaft 14 via the clutch 17 at the center of the flywheel 15. A case 20 is fixedly installed on the side surface of the flywheel 15 according to the shape of the flywheel 15, and the servo motor 2 is provided outside the central portion of the case 20.
1, the drive shaft 21a of the servo motor 21 is aligned with the center of the flywheel 15 and protrudes inward, and the sun gear 22 is fixedly mounted on the drive shaft 21a.

The flywheel 15 and the case 20
The support shaft 23 is concentrically provided laterally across the support shaft 23 at predetermined intervals, and the gears 24, 24, 24 are rotatably loosely fitted on the support shaft 23, and the gears 24, 24, 24 are connected to the sun gear. Two
It meshes with 2 respectively. Further, on the case 20, semicircular guide holes 20a, 20a.
20a is opened and, on the other hand, a pin 25 is provided on the side surface of the gear 24, 24, 24 so as to project from the guide hole 20a, 20a, 2
0a is penetrated, and the weights 26, 26, 26 are fixedly installed at the tip,
The weights 26, 26, 26 are arranged so that their radial positions are aligned with each other, and by driving the servomotor 21, the sun gear 22 is rotated to rotate the gears 24, 24, 24, and the weights 26, 26, 26. 26 as guide holes 20a / 20
It can be moved in the radial direction along the a20a. However, the number of the weights 26 is not limited, as long as they are arranged at equal distances and at equal intervals from the center of the flywheel 15 and can be moved in the radial direction without losing the balance.

The number of revolutions of the flywheel 15 is detected by a sensor 27, which is connected to a control circuit 30. The control circuit 30 further includes the servo motor 21, a clutch (electromagnetic clutch) 17,
A motor 11 and a setter 31 (or a processing program input device) for setting the rotation speed of the motor 11 are connected.

In such a construction, when the number of times of punching is small for one work or the processing is not rushed, the number of revolutions is reduced in consideration of the environment and the like to reduce the noise. You had better go. Therefore, if the rotation speed of the motor 11 is reduced by the setter 31, the kinetic energy of the flywheel 15 also decreases, so the servomotor 21 is driven to rotate the gears 24, 24, 24, and the weights 26, 26, 26. Is moved radially outward (away from the center) to a position that matches the rotation speed (the higher the rotation speed, the farther) to increase the inertia so that the kinetic energy does not decrease. On the contrary, when punching such as nibbling is continuously performed, the setting device 3
1, the rotation speed of the motor 11 is set to be high, and at the same time, the servo motor 21 is driven in the opposite direction to move the weights 26, 26, 26 to the center side to reduce the inertia, and the kinetic energy is set to the above. The kinetic energy is set to be almost the same as the kinetic energy so that the punching work can be performed with energy that does not stop. That is, the distance of the weight 26 from the center of the flywheel 15 is set so as to be inversely proportional to the rotation speed, so that the kinetic energy is constant regardless of the rotation speed.

Further, as another embodiment in which the weight 26 is moved in the radial direction, the weight 26 may be constructed as shown in FIGS. That is, the cylinders 35 are arranged on the side surface of the flywheel 15 at predetermined intervals in the radial direction, and the pistons 26 'are housed in the cylinders 35, respectively, and the pistons 26' are used as weights. Then, the oil feed pipe 3 is provided at each of the center side end and the outer side end of the cylinder 35 so that the piston 26 'can be slid by hydraulic pressure.
6 and 37 communicate with each other, and the oil supply pipes 36 and 36 are connected.
Are respectively connected to a joint 39 rotatably fitted to the outer end of the crankshaft 14, and are provided in the punch press P via oil passages 14a and 14b formed in the crankshaft 14 from the joint 39. And an electromagnetic proportional servo valve 40. The solenoid 40a of the electromagnetic proportional servo valve 40 is connected to the control circuit 30 (not shown in FIG. 5) in the same manner as described above, and when the rotational speed is increased, the piston 26 'is moved toward the center side and the rotational speed is decreased. At times, it is controlled to slide to a position farther from the center so that the kinetic energy is constant as in the above case.

[0015]

Since the present invention is constructed as described above, it has the following effects. That is, since the weight can be moved in the radial direction according to the rotation speed of the flywheel, the kinetic energy can be kept constant regardless of the rotation speed, and productivity can be improved by increasing the punching speed, that is, the rotation speed. By increasing the speed or reducing the number of rotations to reduce noise, it is now possible to use them according to the type of processing.

[Brief description of drawings]

FIG. 1 is a perspective view of a punch press equipped with a punching speed variable press drive device of the present invention.

FIG. 2 is a side view of the flywheel.

FIG. 3 is a sectional view taken along line XX in FIG. 2 and a control block diagram.

FIG. 4 is a side view of a flywheel showing another embodiment of the punching speed variable press drive device.

5 is a sectional view taken along the line YY in FIG.

[Explanation of symbols]

 P Punch press 11 Motor 13 Belt 14 Crankshaft 15 Flywheel 21 Servo motor 22 Sun gear 24 Gear 26 Weight 27 Rotation speed sensor 30 Control circuit

Claims (1)

[Claims] 1. A weight movable in a radial direction is attached to the inside or a side surface of the flywheel, and the weight is moved closer to the center as the flywheel rotates at a higher speed, and the weight is moved away from the center as the wheel rotates at a lower speed. A press drive device with variable punching speed characterized by the above.