JPH0137794Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a slide knockout device installed in a press machine.

Conventionally, the normal pressure slide knockout device installed on the slide of a press machine consists of a knockout bar that pushes down the knockout pin, and an air cylinder that constantly applies a downward biasing force to the knockout bar. The piston rod was fixed with a bolt to prevent the knockout bar from shifting. However, stress is applied to the bolts that hold them in place during each press process, which causes the bolts to break frequently, which poses a risk of malfunctioning the press machine.

The purpose of the present invention is to eliminate this drawback, and by connecting the piston rod and the knockout bar via a spring, prevent the displacement of the knockout bar and damage to the connecting part, thereby improving the safety and operation of the press. It is an object of the present invention to provide a slide knockout device which can be said to improve efficiency. Embodiments of the present invention will be described below with reference to the drawings.

In Fig. 1, a slide 1 of a press machine has air cylinders 2, 2 which act downwardly on both sides, respectively.
are provided, and the piston rods 3, 3 are subjected to a required downward biasing force by compressed air supplied to the air cylinders 2, 2. Windows 4, 4 are opened in the lower portions of both sides of the slide 1, and both ends of a knockout bar 5 passing through the windows 4, 4 are connected to the lower ends of piston rods 3, 3 as will be described later. A knockout pin 6 provided on the lower surface of the slide 1 so as to be movable up and down is in contact with the lower surface of the center of the knockout bar 5. The lower surface of the knockout pin 6 is in direct or indirect contact with the upper surface of a knockout (not shown) of a mold attached to the lower surface of the slide 1.

In FIG. 2, the structure of the connecting portion between the piston rod 3 and the knockout bar 5 is shown. An end plate 7 is fixed to the lower end of the piston rod 3 with bolts 8. A recessed hole 9 is formed on the upper surface of the knockout bar 5, into which the end plate 7 and the head of the bolt 8 are inserted with a slight gap.
The lower surface of the end plate 7 and the bottom surface of the recessed hole 9 are brought into contact with each other. In this case, a concave hole may be provided on the end plate 7 side, and a convex portion that fits therein may be provided on the knockout bar 5 side. A spring case 10 is attached to the upper surface of the knockout bar 5 and surrounds the lower end of the piston rod 3 around the outer periphery of the recessed hole 9. The upper part of the spring case 10 is provided with a flange part 11 that projects inward, and the knockout bar 5 is urged upward and separated from the end plate 7 between the flange part 11 and the end plate 7 of the piston rod 3. A spring 12 is provided to hold it in place.

Next, we will discuss the effect. When the slide 1 descends and press work is performed, the knockout pin 6
is pushed up from the mold side, knockout bar 5
The piston rods 3, 3 are pushed up against the biasing force of the air cylinders 2, 2. When the press work is finished and the slide 1 rises, the pushing force from the mold side disappears, and the piston rods 3, 3
By the urging force of the air cylinders 2, 2, the knockout bar 5 and the knockout pin 6 are pushed down, and the knockout of the mold is pushed down. However, if the force required for knockout is small, the pressure of the compressed air supplied to the air cylinders 2, 2 is lowered and used, but the piston rod is not adjusted to the descending speed of the knockout bar 5 that has been pushed up at this time. The lowering of 3, 3 does not follow, and the piston rod 3, 3
Knockout Bar 5 tries to move away. At this time, the biasing force of the spring 12 acts to prevent the piston rods 3, 3 and the knockout bar 5 from being separated from each other and from being misaligned. Therefore, due to the action of the spring 12, the unreasonable force between the two is alleviated, and damage to the connecting portion can be prevented.

As is clear from the above explanation, according to the present invention, the force acting on the connection between the piston rod and the knockout bar is alleviated while ensuring mutual connection, thereby preventing the fixing bolt from breaking and positional displacement as in the conventional case. This has great practical effects and advantages, such as ensuring the safety of the press and improving the operating rate.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of a main part of a slide of a press machine provided with an embodiment, and FIG. 2 is a partial sectional front view showing a connecting portion between a piston rod and a knockout bar. 1 is a slide, 2 is an air cylinder, 3 is a piston rod, 4 is a window, 5 is a knockout bar, 6 is a knockout pin, 7 is an end plate, 8 is a bolt, 9 is a recessed hole, 10 is a spring case, 11
12 is a flange portion, and 12 is a spring.

Claims (1)

[Scope of Claim for Utility Model Registration] In a normal pressure type knock-out device installed on the slide of a press machine, a pair of air cylinders 2 are provided downward in correspondence with each other on both side surfaces of the slide, and a piston rod 3 of the air cylinder 2 corresponds to the knock-out device. A knock-out bar 5 is provided at the bottom of the slide and guided vertically, and its lower surface abuts a knock-out pin that is guided up and down the slide, and a knock-out bar 5 extends from the outer periphery of the lower end of the piston rod 3 of the air cylinder 2. Flange shaped part and piston rod 3
A cylindrical spring case 10 surrounding the lower end and fixed to the knockout bar 5 is stretched between the upper end and a flange projecting inward to prevent the piston rod 3 and the knockout bar 5 from coming apart. A slide knockout device comprising: a holding spring 12; and fitting means provided on the lower end surface of the piston rod 3 and the upper surface of the knockout bar 5 of the air cylinder 2, and fitting and abutting each other vertically. .