JPS6228100A - Counter balancer for press machine - Google Patents

Abstract

PURPOSE:To eliminate the deformation by the clearances between respective connecting parts and to prevent the generation of heat in the connecting parts by connecting a dynamic balancer to a crank shaft in such a manner that said balancer swings in the direction opposite from the swing direction of a ram and tightening both by means of torsion members. CONSTITUTION:The dynamic balancer 32 is so connected to the crank shaft 23 that said balancer swings at the same stroke as the stroke of the ram 26 and in the direction opposite from the swing direction of the ram. A pair of levers 34, 34 are connected to the upper part of the balancer 32. The other ends of the levers 34 and the ram 26 are connected by the torsion bars 37 and are tightened by means of turnbuckles 36. The ram 26 and the balancer 32 are attracted in the direction of the crank shaft 23 when the levers are tightened in the above-mentioned manner. The generation of the clearances in the respective connecting parts between the ram 26 and the shaft 23 and between the balancer 32 and the shaft 23 is obviated and the reverse deformation by the clearances at the bottom dead point during the pressurization is eliminated. The generation of the heat in the respective connecting parts is thus prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a counterbalance device for punch presses, stamping machines, or similar presses.

[Conventional technology]

A press machine that transmits the rotation of the crankshaft to the ram via a connecting rod and reciprocates the ram has several connecting parts between the ram and the crankshaft, so a counterbalance is provided to balance the entire connecting part. The gap is moved toward the direction where the work load is applied to prevent errors in the molded product during pressure molding.

To explain this example with reference to FIG.
A ram 5 is rotatably provided on the guide 4 of the frame 1 at the bottom of the housing 2 so as to be able to reciprocate in the vertical direction, and the ram 5 is connected to a connecting rod 6 connected to the crankshaft 3 via a connection screw 7. The rotation of the crankshaft 3 causes the ram 5 to reciprocate.

At the top of the housing 2 is a counter consisting of an air cylinder 8, a piston 9 housed in the cylinder 8, and a piston rod 10 whose upper end is connected to the piston 9 and whose lower end is fastened to a bracket 11 on the upper part of the guide 4. A balance 12 is provided to tighten the upper part of the housing 2 and the upper part of the guide 4, and to bring the gap between the entire connecting parts toward the direction in which the work load is applied.

[Problem that the invention seeks to solve]

However, when the ram 5 pressurizes the product to be formed, as shown in FIG. When the ram 5 reaches the dead center, reverse deformation JIB occurs due to the overall clearance and load of each connecting portion with respect to the stroke of the ram 5, and the ram 5 slightly descends from the bottom dead center. This modification ff1
When receiving B, the connecting members slide against each other in the gaps between the connecting parts, and each connecting part generates heat.

In view of this, the present invention is directed to preventing the generation of heat in each connection between the crankshaft and the ram by preventing gaps from forming during the forming operation.

[Means for solving problems]

In order to solve this problem, the present invention provides a press machine in which the rotation of the crankshaft is transmitted to the ram via a connecting rod, and the ram is reciprocated.・B is the same as the length,
A dynamic balancer is connected to the crankshaft in a direction opposite to the swinging direction of the ram, one end of a lever rotatably provided in the housing is pivotally supported on the dynamic balancer, and the other end of the lever is connected to the ram. are connected by a torsion bar, and can be tightened by a tongue buckle provided on the torsion bar.

[For production]

Therefore, by tightening the torsion bar, the ram and the dynamic balancer are drawn toward the crankshaft, so gaps between the ram and the crankshaft and between the dynamic balancer and the crankshaft are no longer created at predetermined locations, and the The amount of deformation due to gaps etc. during compression is eliminated.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

Since the press frame 20 is integrally formed with a housing 22 having a table 21 at the bottom and a ram drive mechanism at the top, a crankshaft 23 rotated by a drive source (not shown) is mounted on both ends of the housing 22. The crankshaft 23 has a flywheel 24 attached to one outer end of the crankshaft 23. Also, the housing 22
A ram 26 is supported by a guide 25.25 disposed below so as to be movable up and down, and a bolster 27 is attached to the upper surface of the table 21.

One end of a connecting rod 28 is rotatably connected to the center of the crankshaft 23, and the other end is connected to a ram 28 via a pin 29.
The rotation of the crankshaft 23 causes the ram 26 to reciprocate up and down.

One end of a pair of connecting rods 30, 30 is connected to both sides of the central part which is 180 degrees out of phase with the central part of the crankshaft 23, while a guide 31 disposed in the housing 22 above the crankshaft 23 .31 supports a dynamic balancer 32 so as to be able to move up and down, the other end of the connecting rod 30.30 is connected to the dynamic balancer 32 through a pin 33, and the dynamic balancer 32 moves up and down as the crankshaft 23 rotates.

The distance between the crankshaft 23 of the connecting rod 28 and the pin 29 is set to be the same as the distance between the crankshaft of the connecting rod 30 and the pin 33, and the dynamic balancer 32 is set to match the stroke length of the ram 26. It moves in the same direction and in the opposite direction to the swinging direction of the ram 26.

A pair of levers 34 are installed on the top of the dynamic balancer 33.
．． One end of 34 is connected, and this lever 34.34
A central portion of the housing 22 is rotatably supported by a pin 35. The other end of the lever 34.34 and the ram 26 are connected by a pair of torsion bars 37.37 having a turnbuckle 36 in the center.

Then, when the tongue buckle 36.36 is rotated to tighten the torsion bar 37.37, the ram 26 and the dynamic balancer 32 are each pulled upward as shown in FIGS. 1 to 4, so that the ram 26 side is , the lower part of the joint between the torsion bar 37 and the ram 25, the lower part of the ram 26 and the bottle 29, the upper part of the bottle 27 and the connecting rod 28, and the lower part of the connecting rod 28 and the crankshaft 23, and during this period There is almost no gap between the two, and on the counter balance 32 side, at the bottom of the joint between the torsion bar 37 and the lever 34, at the bottom between the lever 34 and the dynamic balancer, and at the bottom between the dynamic balancer 32 and the bin 33,
The upper part of the bottle 33 and the connecting rod 30 are always in contact with each other, and the lower part of the connecting rod 30 and the crankshaft 23 are always in contact with each other, and the crankshaft 2
3 and a bearing provided in the housing 22 are always in contact with each other at the lower part.

Therefore, when the ram 26 is located at the top dead center (second
), when the ram 26 is in the intermediate position (Fig. 3), the ram 2
Even when 6 is located at the bottom dead center (FIG. 4), each connecting portion is in contact with each other at the above-mentioned points.

〔Effect of the invention〕

As described above, the present invention connects the dynamic balancer to the crankshaft that drives the ram in the same direction as the stroke length of the ram and in the opposite direction to the swinging direction of the ram, and connects the ram and the dynamic balancer with a torsion bar. Since they are tightened with turnbuckles, the connecting parts of each connecting member are always in contact with each other at predetermined points, so the total clearance and reverse deformation of each connecting part can be brought to a minimum, and the air cylinder Compared to those using counterbalance such as
This eliminates the load of pushing up the balancer, resulting in energy savings.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a partially cutaway front view, FIGS. 2 to 4 are side views of main parts, and FIG. 2 is a ram is at the top dead center, Figure 3 shows the ram at the intermediate position, Figure 4 shows the ram at the bottom dead center, and Figure 5 shows an example of the counterbalance device of a conventional press machine. The cut-away side view shown in FIG. 6 is a stroke diagram of the ram. 26... Ram 28. 30... Connecting rod 32.
...Dynamic balancer 34...Lever 3
6... Tongue buckle 37... Torsion bar Figure 1

Claims (1)

[Claims] 1. Transmits the rotation of the crankshaft to the ram via the connecting rod,
In a press machine that reciprocates the ram, a dynamic balancer is connected to the crankshaft so as to be the same as the stroke length of the ram and in a direction opposite to the swinging direction of the ram, and the dynamic balancer is rotatably mounted on the housing. 1. A counterbalance device for a press machine, characterized in that one end of a lever is pivotally supported, the other end of the lever and a ram are connected by a torsion bar, and can be tightened by a tongue buckle provided on the torsion bar.