JP2002137099A - Press drive method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform operation at a high speed by large output or working torque reduction in a simple structure. SOLUTION: In a press driving device 17 in a press machine, press working is performed by cooperation of a punch and a die by vertically moving a ram 15 through a connecting rod 35 connected rotatably to a crankshaft 31 to drive the punch. The rotation force of a drive pulley 43 rotated by a servomotor 39 is transmitted to a driven pulley 37 provided on the crankshaft 31 through a timing belt 45, and the crankshaft 31 is rotated. Both or any one of the driven pulley 37 and the drive pulley 43 are made variable in a reduction ratio, and the press operation pattern of the ram 15 is freely modified. Punch working is performed in the simple structure at a low speed and high torque, and operation can be performed at the high speed and low torque except therefore.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for driving a press of a press machine which presses a work by cooperation of a punch and a die.

[0002]

2. Description of the Related Art Conventionally, as a driving device such as a turret punch press, the rotational energy of a flywheel is transmitted to a crank mechanism via a clutch brake to move a ram up and down, and to a work as a workpiece. Mechanical drive flywheel type for processing, hydraulic drive type for processing the work by controlling the oil pressure by cylinders and valves, and the ram is directly moved up and down by the power of the servo motor without using the flywheel or clutch brake. In addition, a servo motor driving method for processing a work is known.

[0003]

By the way, among the conventional press driving devices, the stroke for the crank mechanism cannot be changed by the mechanical drive flywheel type. Also,
A coupling mechanism such as a clutch is required, and power for the coupling is required. Further, since the rotation of the flywheel is transmitted by the clutch, the punching speed of the press cannot be varied. Therefore, a punching speed pattern that suppresses noise and vibration cannot be created.

Further, in the hydraulic drive system, the punching speed of the press can be made variable, so that various punching speed patterns can be made and the stroke can be made variable, but the efficiency is poor due to loss such as leakage at the valve. , The power increases. In addition, heat is generated due to poor efficiency, and a cooling device such as an oil cooler is required, resulting in high cost.
Furthermore, the number of hydraulic piping parts is large, the number of assembly steps is increased, and the cost is increased.

In the servo motor drive system, both the punching speed and the stroke of the press can be made variable, and the structure is simple. However, direct machining on a work requires a large power. A deceleration (boosting) mechanism is required, the cost is high, and the inertia is large, which hinders speeding up.

An object of the present invention is to provide a press drive device which has a simple structure and can be operated at a high speed by a large output or a reduction in machining torque.

[0007]

According to a first aspect of the present invention, there is provided a press driving method according to the first aspect of the present invention.
In a press driving method for driving a punch by reciprocating a ram via a connecting rod rotatably connected to a rotatable crankshaft, a rotation transmitting means transmits a rotational force of a driving wheel rotationally driven by a rotational driving means. When rotating the crankshaft by transmitting it to a driven wheel provided on the crankshaft via the drive shaft, the speed reduction ratio of both or any one of the driven wheel and the drive wheel can be varied to freely press the ram. It is characterized in that it is changed to.

Accordingly, since the shape of the driven side and / or the drive side wheels is variable in the reduction ratio according to the pressing operation pattern of the ram, it has a simple structure and a low speed and high torque or a high speed and low torque. Operable. In particular, at the time of processing a workpiece, the ram can be set at a low speed to obtain a large pressurizing ability.

According to a second aspect of the present invention, there is provided a press driving method according to the first aspect, wherein the press operation pattern includes a large pressing force and a low speed during a period from the start to the end of punching of the work. It is characterized in that it is moved at a high speed from the end of punching to the start of punching through the top dead center.

Therefore, the pressing operation pattern is distributed so that the pressing operation is performed efficiently, the ram speeds up when approaching the workpiece, the ram speed is reduced when processing the workpiece, and a large pressing ability is obtained. The speed is increased by rotating the motor forward and backward.

According to a third aspect of the present invention, there is provided a press driving device for a press machine for performing press working on a work by cooperation of a punch and a die, wherein a driving wheel rotatably driven by rotary driving means is rotatable. Provided on the crankshaft, a driven wheel that transmits the rotational force of the drive wheel via rotation transmission means,
A ram that drives a punch via a connecting rod rotatably connected to the crankshaft is reciprocally provided, and the driven wheel and / or the drive wheel can have a variable reduction ratio in accordance with a pressing operation pattern. Characterized in that the shape is

Therefore, the operation is similar to that of the first aspect, and since the shape of the driven side and / or the driving side wheels is variable in accordance with the pressing operation pattern of the ram, the structure is simple. Thus, high-speed operation can be achieved by a large output or a reduction in machining torque. In particular, the ram can be set at a low speed during the processing of the workpiece to obtain a large pressing ability.

According to a fourth aspect of the present invention, there is provided a press driving device according to the third aspect, wherein the outer peripheral shape of the wheel provided with the variable reduction ratio is between the start and end of the punching of the work. In order to move the wheel at a high pressure and at a low speed, the outer peripheral range in which the reduction ratio radius from the rotation center of the wheel to the outer periphery is increased, and to move the punch at a high speed from the end of the punching to the start of the punching through the top dead center. An outer peripheral range in which the reduction ratio radius is reduced.

Therefore, the press operation pattern is distributed so that the press operation pattern is an efficient press operation, the ram speed is high when the ram approaches the work, and the pressurization capacity is low when the work is processed. Is obtained, and when the motor returns to the top dead center, the motor is rotated forward and backward to increase the speed.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Referring to FIGS. 5 and 6, a turret punch press 1 of, for example, a punch press as a press machine includes a portal frame 3 which is connected to a lower frame 5. , An upper frame 7 and left and right side frames 9 connecting the lower frame 5 and the upper frame 7.

The lower frame 5 supports a rotatable lower turret 11, and the upper frame 7 supports a rotatable upper turret 13. Moreover,
A plurality of dies D are mounted on the circumference of the lower turret 11 at appropriate intervals, and a plurality of punches P are mounted on the circumference of the upper turret 13 at appropriate intervals.

Of the plurality of dies D and punches P mounted on the lower turret 11 and the upper turret 13, respectively,
In FIG. 5, the position of the die D and the punch P mounted on the right end is the punching processing position K. The upper frame 7 above the punching position K is provided with a vertically movable ram 15. Moreover, a press drive device 17 for driving the ram 15 is provided on the upper frame 7.

On the right side of the lower frame 5, a work movement positioning device 19 is provided. That is, a fixed center table 21 is provided on the lower frame 5 on the right side in FIGS. 4 and 5 at the punching processing position K, and the center table 21 is vertically moved in FIG. (The horizontal direction in FIGS. 4 and 5)
A side table 23 is provided which is movable to the side.

On the side table 23, a carriage base 25 extending in the X-axis direction (vertical direction in FIG. 5) across the center table 21 is provided integrally. On the carriage pace 25, a carriage 27 movable in the X-axis direction is provided. Moreover, the carriage 27 is provided with a plurality of work clamps 29.

With the above structure, the carriage 27 is moved in the X-axis direction while the work W is clamped by the work clamp 29, and the carriage base 25 is moved in the Y-axis direction. It is moved to the position of the punching position K and positioned. By driving the press driving device 17 in this state, the ram 15 moves up and down, and the punch P is pressed, and the work W is punched by the cooperation of the punch P and the die D.

The press driving device 17 which is a main structure in the embodiment of the present invention will be described in more detail. Referring to FIG. 1 as well, as the press driving device 17, a crankshaft 31 is attached to the upper frame 7. The shaft 33 is supported substantially horizontally by a support shaft portion 33 via a bearing (not shown), and the upper end of the ram 15 is rotatably connected to the crankshaft 31 via a connecting rod 35. Further, at both ends of the crankshaft 31, for example, a driven pulley 37 as a driven wheel is journaled via a clutch mechanism (not shown) so as to be freely engaged and disengaged. Note that the driven wheel may be provided on only one side of the crankshaft 31.

Further, for example, a servo motor 39 as a rotation driving means of the rotation driving device 17 is connected to the upper frame 7.
The drive shaft 41 of the servo motor 39 is provided with, for example, a drive pulley 43 as a drive wheel. For example, a timing belt 45 as a rotational force transmitting means is wound around the driven pulley 37 and the drive pulley 43, and the rotational force of the drive shaft 41 of the servomotor 39 is applied to the drive pulley 43, the timing belt 45, and the driven pulley 3.
7, the crankshaft 31 is rotated.

The driving pulley 43, the driven pulley 37,
The timing belt 45 and the like constitute a reduction mechanism for transmitting the power of the servo motor 39 to the crankshaft 31. This reduction mechanism may be configured by a drive sprocket, a driven sprocket, a chain, or the like in addition to the above.
Alternatively, another reduction mechanism may be used.

Each of the wheels such as the pulleys 37 and 43 (or sprockets) has a shape in which the reduction ratio can be varied in accordance with the pressing operation pattern on both or one of the driving side and the driven side.

For example, the press operation pattern of the present embodiment is such that the ram 15 is moved at a large pressure and at a low speed from the start to the end of the punching of the work, and the top dead center is set from the end of the punching. After that, the ram 15 is moved at high speed until the start of punching. In the present embodiment, the shape of the driven pulley 37 conforms to the above-described press operation pattern, and as shown in FIG. 1, one of the semicircular sides (the upper semicircular side in the state of FIG. 1). An outer peripheral range of low speed and high torque in which the reduction ratio radius a is increased, and an outer peripheral range of high speed and low torque in which the reduction ratio radius b on the other semicircle side (the lower semicircle side in the state of FIG. 1) is reduced. It is configured. That is, the shape of the driven pulley 37 is not a perfect circle, but is, for example, a shape like a crushed dumpling.

With the above structure, the rotational force of the driven pulley 37 is transmitted to the crankshaft 31 by the operation of the clutch mechanism, and the rotation of the crankshaft 31 causes the ram 15 to move up and down via the connecting rod 35, and the ram 15 punches the ram 15. P is hit, and the plate-shaped workpiece W moved and positioned at the processing position K is punched by the cooperation of the punch P and the die D.

At this time, since the shape of the driven pulley 37 is deformed as described above, the trajectory of the ram stroke over time is a normal (conventional) almost perfect circle as shown by the solid line in FIG. The trajectory shown by the dotted line in FIG. 3 is deformed by the driven pulley having a shape, and the reduction ratio with respect to the driving pulley 43 is partially varied on the outer periphery of the driven pulley 37. In other words, the ram 15 rapidly descends to almost immediately before the punching of the workpiece, and slowly descends at a high pressure during the punching.

More specifically, FIG. 2A shows FIG.
This indicates a state in which the ram 15 is located at the top dead center as indicated by the point A. Since the small radius side of the driven pulley 37 is located in the upper semicircle, the timing belt 45 exerts a weak force. Fig. 2 (A)
2B, that is, from the top dead center to the point immediately before punching of the workpiece from the point A in FIG. 3 to the point B, the descending force of the ram 15 is small.
The descending speed of 5 becomes faster.

In the process of shifting from FIG. 2B to FIG. 2C and FIG. 2D, since the large radius side of the driven pulley 37 is located on the upper semicircle side, the timing belt 45 exerts a stronger force and Since the workpiece is rotated at a low speed, the descending speed and the ascending speed of the ram 15 are reduced in the process of shifting from the point B in FIG. 3 to the point D in FIG. The descending force of the ram 15, that is, the punch pressurizing ability increases.

[0031] The section from point A in FIG. 3 to approximately point B V ₁
And then, when the section from the point B to approximately point C and V _2, the moving speed becomes V _1> V _2.

In the process of transitioning from FIG. 2D to FIG. 2A, the driven pulley 37 is rotated by the timing belt 45 with a small force and at a high speed because the small radius side of the driven pulley 37 is located on the upper semicircle side. The rising speed of the ram 15 increases during the transition from the point C in FIG. 3 to the point A in FIG. Incidentally, if the section to shift to the point A from the point C in FIG. 3, V _3, the moving speed becomes _{V 3> V 1> V 2} .

As described above, since the shape of the driven pulley 37 is variable and the reduction ratio is variable, the pressing operation pattern of the ram can be freely changed. In this embodiment, when the ram 15 approaches the work, the speed becomes high, and A large pressurizing ability is obtained at a low speed during machining, and the servo motor 39 is rotated forward and reverse to stroke the ram 15 in a region on the time t2 side when returning to the top dead center, thereby increasing the speed. . Efficient punching can be performed.

FIG. 4 shows another embodiment which is an alternative to FIG. In FIG. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted.

In FIG. 4, a cam 47 is mounted on the support shaft 33 instead of the driven pulley in FIG. in this case,
The center O1 of the support shaft 33 and the center of the crankshaft 31, that is, the center O2 of the connecting rod 35 are eccentric by an eccentric amount E.

By rotating the drive pulley 43 while keeping the radius of the drive pulley 43 constant at r2, the same operation and effect as in FIG. 1 can be obtained.

The present invention is not limited to the above-described embodiment, but can be embodied in other forms by making appropriate changes. In the present embodiment, the case where only the driven pulley 37 has a variable reduction ratio has been described as an example. (Or the driving sprocket) may have a shape in which the reduction ratio is variable in accordance with the pressing operation pattern. Further, the wheel having a variable reduction ratio may have a symmetrical shape with respect to the rotation center point.

[0038]

As will be understood from the above description of the embodiments of the invention, according to the first aspect of the present invention, the shape of the wheel on either the driven side or the drive side or any one of the wheels is determined by the ram press. Since the reduction ratio is variable in accordance with the operation pattern, it is possible to operate at a high speed with a simple structure and a large output or reduced machining torque. Particularly when the ram is processing a workpiece, the ram can be set at a low speed to obtain a large pressing ability.

According to the second aspect of the present invention, the pressing operation pattern can be changed so that the pressing operation can be performed efficiently. You can get
Further, when the motor returns to the top dead center, the motor can be rotated forward and reverse to increase the speed.

According to the third aspect of the invention, the operation is the same as that of the first aspect, and the shape of the driven side and / or the drive side wheels is variable in accordance with the pressing operation pattern of the ram. Therefore, with a simple structure, high-speed operation can be achieved by a large output or a reduction in machining torque. Particularly when the ram is processing a workpiece, the ram can be set at a low speed to obtain a large pressing ability.

According to the fourth aspect of the present invention, the effect is the same as that of the second aspect, and the pressing operation pattern can be changed so as to achieve an efficient pressing operation. In addition, a large pressurizing ability can be obtained at a low speed at the time of processing the workpiece, and the speed can be increased by rotating the motor forward and backward when returning to the top dead center.

[Brief description of the drawings]

FIG. 1, showing an embodiment of the present invention, is a schematic explanatory view of a press driving device.

FIGS. 2A to 2D are explanatory diagrams of the operation of the press driving device.

FIG. 3 is a graph of a ram stroke over time by a press driving device.

FIG. 4 is a schematic explanatory view of a press driving device according to another embodiment instead of FIG. 1;

FIG. 5 is a side view of a turret punch press showing an example of the press machine of the present invention.

FIG. 6 is a plan view of FIG.

[Explanation of symbols]

 Reference Signs List 1 turret punch press (press machine) 15 ram 17 press drive device 33 support shaft 31 crankshaft 35 connecting rod 37 driven pulley (driven wheel) 39 servo motor (rotation driving means) 41 drive shaft 43 drive pulley (drive wheel) 45 timing Belt (rotation transmission means)

Claims (4)

[Claims] 1. A press for driving a punch by reciprocating a ram via a connecting rod rotatably connected to a rotatable crankshaft when performing press working on a workpiece by cooperation of a punch and a die. In the driving method, when the rotational force of the drive wheel rotationally driven by the rotational driving means is transmitted to the driven wheel provided on the crankshaft via rotation transmission means to rotate the crankshaft, the driven wheel and the driven wheel are rotated. A press driving method characterized in that a press operation pattern of a ram is freely changed by changing a reduction ratio of both or any one of the drive wheels. 2. The method according to claim 1, wherein the pressing operation pattern moves the workpiece with a large pressing force and at a low speed during a period from the start to the end of the punching, and a period from the end of the punching to the start of the punching through the top dead center. 2. The method of driving a press according to claim 1, wherein the step (c) is moved at a high speed. 3. A press driving device of a press machine for performing a press working on a work by cooperation of a punch and a die, wherein a driving wheel rotatably driven by a rotation driving means is rotatably provided, and the rotational force of the driving wheel is reduced. A driven wheel transmitting through a rotation transmitting means is provided on the crankshaft, and a ram for driving a punch via a connecting rod rotatably connected to the crankshaft is provided so as to be reciprocally movable. A press drive device characterized in that both or any one of them has a shape in which a reduction ratio is variable in accordance with a press operation pattern. 4. The outer peripheral shape of a wheel provided with a variable reduction ratio has a reduction ratio radius from the center of rotation of the wheel to the outer periphery so that the workpiece can be moved with a large pressing force and at a low speed from the start to the end of punching. 4. An outer peripheral area in which the diameter of the reduction ratio radius is reduced so as to move at high speed from the end of punching to the start of punching through top dead center from the end of punching. The press drive as described.