JPS5816749A - Forging press - Google Patents

Abstract

PURPOSE:To forge and form a product having prescribed thickness without requiring a temperature control of a material, by executing a forward and reverse rotation driving control so that a crank shaft in a forging press starts from the top dead center, and becomes a stroke end at an angle position being slightly less than 180 deg.. CONSTITUTION:A fly-wheel 4 engaged with a gear is rotated by a forward rotation of a hydraulic motor 12, a crank shaft 1 is rotated by said rotation, and an up-and-down motion is given to a connecting rod 6 by a crank pin 2. When the connecting rod lowers, a slide 8 lowers, and a material which heated between an upper metallic die 9 installed to its tip and a lower metallic die 10 is forged. In this case, a forward and reverse rotation driving control is executed so that a rotation of the crank shaft 1 starts from the top dead center and becomes a stroke end at an angle position being slightly less than 180 deg., elongation of a frame 3 caused by reaction force is absorbed, and a material of a low temperature can also be forged and formed exactly to prescribed thickness.

Description

[Detailed description of the invention] The present invention relates to improvements in forging presses.

In the conventional forging press, as shown in Fig. 3, a crankshaft l equipped with an eccentric crankpin 2 rotates at 3600 revolutions, and a slide 8 connected to the crankpin 2 via a connecting shaft 6 is a crankshaft. The structure is such that it moves up and down with one rotation. In this conventional device, when the temperature of the material to be molded (the material has been heated in advance) is high, the pressure applied by the slide 8 is small, so the frame 3 itself that receives the reaction force stretches only slightly. In the case of bottle forging, the formed product has approximately a predetermined thickness, but when the temperature of the material to be formed is low, the pressure applied by the slide 8 becomes large, and the frame 3 receives the reaction force. Because the elongation increases,
The thickness of the molded product increases. in this way,
There was a drawback that the accuracy of the product could vary depending on the temperature of the material. Further, in order to forge the product to have a constant thickness, it is necessary to strictly control the material temperature, and this material temperature control is troublesome and becomes a factor that inhibits productivity.

The present invention has been made to solve the above-mentioned drawbacks.
The aim is to provide a forging press that can forge products of a predetermined thickness without requiring temperature control of the material.The feature is that the crankshaft can be pressed from 180' to 70' from top dead center. The point is that the forward and reverse rotation drive is controlled so that the stroke end is at the near angular position.

Hereinafter, the embodiment will be explained with reference to the drawings.

In the figure, 1 is a crankshaft with an eccentric crank pin 2 in the middle, which is rotatably supported by a frame 3, with a flywheel/I/4 at one end and a brake disc 5' at the other end. The key is locked. A connecting rod 6 has an upper end rotatably connected to the crank pin 2, and a slide 8 is connected to the lower end via a pin 7. 9 is 1 gold 11.1 attached to slide 8
0 is a lower mold mounted on the frame 3 facing the lower mold 9. 11 is a gear tooth carved on the outer periphery of the flywheel/I/4, and meshes with a pinion gear 14 fixed to an output shaft 13 of a hydraulic motor 12. 16 is
This is a limit switch installed at the slide stroke end position where the upper mold 9 comes into contact with the lower mold 10.The activation signal of this limit switch 16 switches the solenoid valve 16, thereby causing the hydraulic motor IB to operate. It's about to be reversed. 17 is a limit switch for detecting the top dead center of the SFPID. This limit switch 17 is interlocked with the limit switch 15, and the activation signal of the limit switch 15 stops the release 12 in response to the signal from the limit switch 17, and at the same time deactivates the brake release solenoid valve (not shown). The brake disc 51 is restrained by the force of a spring built into the brake device 5, and the crankshaft 1 is braked.

Since the present invention is configured in this way, its operation is as follows:
When the start button (not shown) is pressed and the solenoid valve 16 is activated to rotate the hydraulic motor 12 in the forward direction, the flywheel 4 rotates at an accelerated rate due to gear engagement, and this rotational force is transferred to the crankshaft 1.
It is transmitted in this order: → crank pin 2 → connecting rod 6, and slide 8 is lowered. A material heated to an elevated temperature is charged in advance between an upper mold 9 attached to the lower end of the slide 8 and a lower mold 1o disposed opposite thereto.
This material is shaped by the applied pressure (kinetic energy) caused by the descent of the slide 8. 1. By the way, in this molding process, the frame 8 is slightly elongated by 1 reaction force, but the amount of elongation of the frame 3 depends on the rotation angle range of the crank shirt l-1 from the start of pressurization until the molds come into contact with each other. 0
Since 2 m of water can be absorbed sufficiently, even if the temperature of the material to be formed is low, it can be forged into a product of a predetermined thickness.

When the limit switch 15 is activated by the slide 8 at the same time as the molds come into contact with each other, the solenoid valve 16 is switched by the signal, and the hydraulic motor 12 is reversed.
The slide 8 rises and the 1st step is completed.

As described above, according to the present invention, it is possible to forge into a product of a constant thickness without strictly controlling the material temperature, thereby improving workability and product precision, which has a great effect on improving productivity. .

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of a forging press according to the present invention. FIG. 2 is a functional diagram, and FIG. 3 is a functional diagram of a conventional forging press. l...Crankshaft, 2゜ No. 33

Claims (1)

[Claims] A forging press characterized in that forward and reverse rotation drive control is performed so that the crankshaft starts from top dead center and ends its stroke at an angular position slightly before 180@.