JPH081385A - Toggle type punch driving device - Google Patents

Abstract

PURPOSE:To enable high-speed punching and to prevent excessive load at the time of punching. CONSTITUTION:The upper and lower ends of a crooking lever 18 which is freely flexible in the middle part are each connected freely rotatably to a fulcrum member 28 and a ram 14, a forward/backward moving member 19 is connected to the crooking part of this crooking lever 18. The forward/backward moving member 19 is for driving to crook the crooking lever 18, which is made an extended state in the middle of a forward/backward moving stroke. The fulcrum member 28 is in a lever shape freely rotatable vertically, and is received in an excessive load absorbing mechanism 27. This mechanism 27 is constituted of a second crooking lever 29, which is supported between the free end of the fulcrum member 28 and a frame, and an air cylinder 30. The second crooking lever 29 is supported at a minute angle of crooking with a stopper 42a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toggle type punch driving device mounted on a punch press machine.

[0002]

2. Description of the Related Art Conventionally, in a mechanical punch press, as a punch driving device for raising and lowering a ram, a crank type device in which a lower end of a pitman arm connected to a crank shaft is connected to a ram is used.

[0003]

In this mechanism, the ram is moved up and down once by one rotation of the crankshaft. Therefore, in order to reduce the processing time by high-speed punching,
It is necessary to increase the rotation speed of the crankshaft. But,
The rotation speed of the crankshaft is limited by the rotation speed of the motor and the bearing performance, and it is difficult to increase the punch speed. Further, in this crank mechanism, it is difficult to prevent damage to each mechanism portion against overload of the punching load. Therefore,
As a solution to the above speedup, the present applicant has tried to use a toggle drive mechanism for the punch drive mechanism. As a result, one reciprocating motion of the advancing / retreating member punches twice, enabling high-speed punching. However, protection of each mechanical part against overload of punching load has not been solved yet.

The object of the present invention is to enable high-speed punching,
Another object of the present invention is to provide a toggle type punch driving device having a simple structure capable of protecting each part against overload during punching. Another object of the present invention is to more appropriately prevent overload according to load conditions such as plate thickness and material.

[0005]

SUMMARY OF THE INVENTION A toggle-type punch driving device of the present invention is a punch provided with a bending lever for raising and lowering a ram by a bending operation, and an advance / retreat member connected to a bending portion of the bending lever to perform bending driving. The drive device is provided with an overload absorbing mechanism that elastically supports the fulcrum member of the bending lever so as to be able to escape upward. The ram is supported so as to be movable up and down and drives the punch tool.
The bending lever is bendable at an intermediate portion, and upper and lower ends thereof are rotatably connected to the fulcrum member and the ram, respectively. The advancing / retreating member is connected to the advancing / retreating drive device, and brings the bending lever into an extended state in the middle of the advancing / retreating stroke. The fulcrum member may be a lever-shaped member that is supported by a frame at its base end so as to be vertically rotatable. In this case, the overload absorbing mechanism includes a second bending lever whose lower end is rotatably connected to the free end of the fulcrum member and whose upper end is rotatably connected to the frame, and which is bendable at an intermediate portion. An elastic supporting mechanism that elastically prevents the bending lever from bending in a state where the bending angle is a minute angle may be provided. The elastic support mechanism is provided with a support angle adjustment mechanism that enables adjustment of the minute angle. The support angle adjusting mechanism includes, for example, a stopper that engages in the vicinity of a bent portion of the second bending lever to prevent the bending lever from expanding, and an entrance / exit adjustment mechanism that allows the stopper to move in and out in the bending direction of the second bending lever. It can consist of and.

[0006]

According to the punch drive device having this structure, the bending lever is alternately bent to both sides of the extended position by the forward / backward drive of the forward / backward member, and the ram moves up and down. In this case, when the advancing / retreating member is at the stroke end, the ram is located at the top dead center, the ram descends to the bottom dead center at the center of the stroke, and when it advances to the other stroke end, the ram returns to the top dead center. Therefore, the ram is moved up and down twice by one reciprocating motion of the advancing / retreating member, which enables high-speed punching. The overload that acts on the ram during punching is absorbed by the overload absorption mechanism, and damage to each part is prevented. The fulcrum member is a lever-shaped member that is rotatable up and down, and the overload absorbing mechanism is a second bending lever connected to the free end of the fulcrum member, and this bending lever is elastically bent at a minute bending angle. In the case of the elastic supporting mechanism for blocking, the load acting on the fulcrum member by the punching load can be received with a small force, and the elastic supporting mechanism can be simple. That is, the punching load acting on the fulcrum member acts as a compressive force on the second bending lever, but the force applied to the elastic support mechanism is a slight force because it is a component force generated by the minute bending angle. The force applied to the elastic support mechanism is also reduced by the action of the "lever" of the fulcrum member. Therefore, the punching load can be supported by the elastic support mechanism having a simple structure so as to prevent overload. Moreover, since the elastic support mechanism is provided with the support angle adjustment mechanism capable of adjusting the minute angle, optimal overload prevention can be achieved according to load conditions such as plate thickness and material, and safety can be ensured. it can. When the support angle adjusting mechanism is composed of the stopper and the entrance / exit adjusting mechanism, it is possible to reliably prevent the second bending lever from being linear, and therefore, only by adjusting the entrance / exit position of the stopper, it is possible to make it as small as possible. The angle can be set, and the maximum allowable load until the overload prevention function can be easily set to a large value.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cutaway side view of a punch press equipped with this toggle type punch driving device. Upper frame portion 1a and lower frame portion 1 in C-shaped frame 1
An upper turret 2 and a lower turret 3 are coaxially installed in b, and a plurality of punch tools 6 and die tools 7 are installed in the upper and lower turrets 2 and 3 side by side in the circumferential direction. When each punch tool 6 is indexed to the ram position, it is connected to the ram 14 and driven up and down. Ram 14
Is supported by the upper frame portion 1a via the guide member 8 so as to be able to move up and down, and is driven up and down by the toggle type punch drive device 13.

The punch drive device 13 drives a bending lever 18 for raising and lowering the ram 14 by a bending operation with an advancing / retreating member 19 which is capable of advancing and retracting in a horizontal direction. The advancing / retreating member 19 drives a servo motor 21 as a driving source. It is driven by a crank type forward / backward drive device 20. The bending lever 18 is formed by connecting a short upper lever 18a and a long lower lever 18b to each other via a pin 41 so that the lower lever 18b has a lower end rotatably pin-connected to an upper end of the ram 14. The lower lever 18b is provided with a long hole-like stealing hole 32 to the extent that the strength is not impaired, and the weight is reduced. Upper lever 1
The upper end of 8a is rotatably pin-coupled to a lever-shaped fulcrum member 28 at a fulcrum A. The fulcrum member 28 has a base end attached to the bracket 17 of the upper frame portion 1a so as to be vertically rotatable. The fulcrum member 28 is an overload absorbing mechanism 27 for switching the vertical position of the ram 14. Supported as possible.

The advancing / retreating member 19 is formed by connecting an advancing / retreating transmission lever 19c to the tip end side of an advancing / retreating member main body 19b so as to be rotatable up and down. It is rotatably connected. By the vertical swing of the advance / retreat transmission lever 19c, the vertical displacement of the bending portion due to the bending operation of the bending lever 18 is absorbed. The advancing / retreating lever main body 19b includes two parallel guide rails 31, 31 (FIG. 2) provided on the upper frame portion 1a.
Further, it is supported so as to be able to move back and forth through the guide member 19a. The advancing / retreating drive device 20 includes the output shaft 2 of the servo motor 21.
1a is provided with a disk-shaped crank 22 and the crank 22
One end of the connecting rod 26 is rotatably connected to the eccentric position, and the other end of the connecting rod 26 is rotatably connected to the base end of the advancing / retreating member main body 19b. In the servo motor 21,
In addition to a pulse coder (not shown), a detector 36 for detecting the rotational position of the output shaft 21a via gears 33 and 34 is attached.

The overload absorbing mechanism 27 includes a second bending lever 29, and an air cylinder 30 which is an elastic support mechanism for preventing the bending lever 29 from bending when the bending angle α (FIG. 3) is a minute angle. Stopper type support angle adjustment mechanism 4
2 and. The second bending lever 29 is the upper lever 29.
The lower lever 29b is rotatably pin-coupled to the action point B of the tip of the fulcrum member 28. The upper end of the upper lever 29a is rotatably supported by the upper frame 1a at a fulcrum C. The air cylinder 30 has a piston rod 30a whose tip is provided with a second bending lever 29.
It is rotatably connected to the pin of the bent portion. The base end 30b of the cylinder body of the air cylinder 30 is supported by the upper frame 1a so as to be vertically rotatable. The support angle adjusting mechanism 42 is provided with a stopper 42a that engages with the bent portion of the second bending lever 29, and the stopper 42a is installed on the upper frame 1a via an entrance / exit adjusting mechanism 43 composed of an adjusting screw. There is. The stopper 42a is adjusted so that the bending angle α of the second bending lever 29 becomes a predetermined minute angle.

The operation of the above configuration will be described. When the crank 22 of the advancing / retreating drive mechanism 20 makes one revolution, the advancing / retreating member 19 moves to 1
It moves back and forth. In the one reciprocating motion, while the advancing / retreating member 19 reaches the center position of the advancing / retreating stroke S from the left end position in FIG. 3, the bending lever 18 changes its bent portion from the left bent state to the extended state, Accordingly, the ram 14 descends from the top dead center to the bottom dead center. Advance member 1
While 9 reaches the right end position from the center position of the stroke S, the bending lever 18 changes its bent portion from the extended state to the rightward bent state, which causes the ram 14 to move from the bottom dead center to the top dead center. Rise to. Even when the advancing / retreating member 19 returns from the right end position to the left end position, the ram 14 moves up and down as described above. In this way, while the advancing / retreating member 19 makes one reciprocating advancing / retreating operation, the ram 14 repeats the raising / lowering operation twice, and the punching operation by the punch tool 6 is performed twice. Therefore, high-speed punching is possible and the processing time can be shortened.

In the punching operation, the stroke speed of the ram 14 is the lowest near the bottom dead center if the stroke speed of the advancing / retreating member 19 is constant.
Is driven by the crank 22, the maximum speed is at the center of the stroke, and the speed difference from the low speed is large. Therefore, after the punch tool 6 penetrates the work, the speed near the bottom dead center is kept high. Therefore, high-speed punching can be performed. The drive source of the advancing / retreating member 19 is the servo motor 21.
Therefore, the speed control and the position control are easy. Therefore, the ram speed and the ram position can be adjusted according to the plate thickness and the material of the work to improve the processing quality and reduce the noise.

The overload generated on the ram 14 during the punching operation is released as follows. The punching force applied to the fulcrum A of the bending lever 18 for raising and lowering drive is the lever-like fulcrum member 28.
Is transmitted to the action point B at the tip of the. The pushing force of the point of action B is supported by the positional relationship between the fulcrum C of the second bending lever 29 and the force point D. That is, a slight force is applied to the air cylinder 30 by bending the second bending lever 29 by a minute angle α without completely extending it. Since this force is a component force generated by the minute bending angle α of the compressive force applied to the bending lever 29, it is a slight force and does not require the air cylinder 30 to have a large output. However, when an excessive force is applied to the bending lever 18 for lifting / lowering drive, a pressure equal to or higher than the set pressure is also applied to the air cylinder 30, and the piston is pushed back. In this way, the overload of the bending lever 18 for raising and lowering is elastically absorbed, and damage to each part due to the overload is prevented. The bending angle α of the second bending lever 29 can be adjusted by advancing and retracting the stopper 42a, and proper overload prevention according to the plate thickness, material, etc. can be performed. By setting the bending angle α of the second bending lever 29 to be as small as possible, the punching load until the overload prevention function of the air cylinder 30 operates can be set to the maximum. Since the stopper 42a is used, even if the bending angle is reduced,
It is possible to reliably prevent the second bending lever 29 from being inadvertently linearly bent in the opposite direction. Further, when the air cylinder 30 is greatly shortened, the bending lever 18 for raising and lowering can be greatly raised together with the fulcrum member 28, and the punch tool 6 can be replaced in this raised state.

4 and 5 show another embodiment. In this example, the advancing / retreating member 19 is installed as a single member on the guide member 45 of the upper frame portion 1a so as to be advancing / retreating. The connection between the advancing / retreating member 19 and the bending lever 18 is performed by the advancing / retreating lever 19
By inserting the bending portion of the bending lever 18 into the through hole 44 provided in the above, the vertical displacement of the bending portion due to the bending operation of the bending lever 18 can be absorbed. The fulcrum member 28 is
It is fixed to the frame 1 via an overload absorbing mechanism 27 made of a hard elastic body. The other structure is the same as that of the above embodiment. Although not described and shown in the above embodiment, the plate material W is gripped by the work holder 15 of the work feeding mechanism and sent on the table 16 to the punch position P by the ram 14.

[0015]

The toggle type punch driving device of the present invention is
A bending lever whose upper and lower ends are connected to a fulcrum member and a ram, respectively, and is bendable at an intermediate portion; Since the advancing / retreating member is provided, the ram moves up and down twice by the advancing / retreating operation of the advancing / retreating member, so that high-speed punching can be performed and the punching time can be shortened. Further, since the overload absorbing mechanism that elastically supports the fulcrum member of the bending lever so as to be released upward is provided,
The overload at the time of punching that acts on the ram is absorbed by the overload absorption mechanism, and damage to each part is prevented. Since the overload absorption mechanism supports the fulcrum member at the upper end of the bending lever, it has a simple structure. The fulcrum member is a lever-shaped member supported at the base end in a vertically rotatable manner on the frame,
Further, when the overload absorbing mechanism is composed of a second bending lever connected to the free end of the fulcrum member and an elastic support mechanism for elastically blocking the bending lever at a minute bending angle, With such a configuration, overload prevention can be realized. Moreover, since the elastic support mechanism is provided with the support angle adjustment mechanism capable of adjusting the minute angle, optimal overload prevention can be achieved and safety can be ensured in accordance with load conditions such as plate thickness and material. it can. When the support angle adjusting mechanism is composed of the stopper that engages with the second bending lever and the entrance / exit adjusting mechanism thereof, it is possible to reliably prevent the second bending lever from being in a linear state, and only adjust the stopper position. Therefore, the angle can be made as small as possible. Therefore, it is possible to easily set a large maximum allowable load until the overload prevention function.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing a punch press machine equipped with a toggle type punch drive device according to an embodiment of the present invention.

FIG. 2 is a plan view of the toggle punch driving device.

FIG. 3 is a schematic explanatory view of the toggle type punch driving device.

FIG. 4 is a schematic cutaway side view of a toggle type punch driving device according to another embodiment of the present invention.

FIG. 5 is a cutaway side view of a punch press machine equipped with the toggle type punch drive device.

[Explanation of symbols]

6 ... Punch tool, 14 ... Ram, 17 ... Support member, 18 ...
Bending lever, 19 ... Forward / backward member, 20 ... Forward / backward drive device, 2
DESCRIPTION OF SYMBOLS 1 ... Servo motor, 27 ... Load absorption mechanism, 29 ... 2nd bending lever, 30 ... Air cylinder (elastic support mechanism), 3
2 ... Stealing hole, 42 ... Support angle adjusting mechanism, 42a ... Stopper, 43 ... Entrance / exit adjusting mechanism

Claims (3)

[Claims] 1. A vertically movable ram for driving a punch, a bending lever whose upper and lower ends are rotatably connected to a fulcrum member and the ram, and can be bent at an intermediate portion, and a bending portion of the bending lever. And a forward / backward drive member connected to the forward / backward drive source to extend the bending lever in the middle of the forward / backward stroke, and an overload absorbing mechanism that elastically supports the fulcrum member so as to be able to escape upward. Punch drive. 2. The fulcrum member is a lever member rotatably supported on a frame at a base end in a vertically rotatable manner, and the overload absorbing mechanism is rotatably connected at a lower end to a free end of the fulcrum member. A second bending lever whose upper end is rotatably connected to the frame and is bendable in the middle portion; and an elastic support mechanism for elastically preventing the bending lever from bending when the bending angle is a minute angle. The toggle-type punch drive device according to claim 1, further comprising a support angle adjusting mechanism that enables adjustment of the minute angle. 3. A stopper, wherein the support angle adjusting mechanism engages in the vicinity of a bent portion of the second bending lever to prevent extension of the bending lever, and the stopper in the bending direction of the second bending lever. The toggle-type punch drive device according to claim 2, further comprising an in-and-out adjusting mechanism for moving in and out.