JPS6338280B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure regulating device for a slide counter balancer in a press machine.

There is a small amount of play in the crankshaft bearing that drives the press slide and the connection between the connecting rods, but if you ignore this play and drive the slide, the slide will not move smoothly. This results in noise generation and unnecessary loss of power.
There are several ways to balance the slide weight: using a heavy hammer, using a spring, and using air pressure, but the balancing method using air pressure is the best because the balancing force remains constant without being affected by the stroke position or slide adjustment. Moreover, by adjusting the air pressure with a pressure regulating valve, there is the advantage that perfect balance can be easily achieved according to the weight of the mold used.

Incidentally, in a balance device that uses air pressure, adjustment of the air pressure inside the balance cylinder becomes an important problem. Conventionally, this air pressure adjustment is known, for example, as disclosed in Japanese Patent Application Laid-open No. 136600/1983. This basically adjusts the air pressure so that the slide rises by a stroke corresponding to the gaps between the various parts that support the slide.
A position detection mechanism for determining this stroke is provided between the crown and the slide in addition to the balance cylinder.

On the other hand, another example is shown in Japanese Utility Model Application Publication No. 160299/1983. In this case, to adjust the pressure inside the cylinder, a hydraulic cylinder is installed between the crown and the slide, and a small stroke is similarly placed between the stopper provided on the slide and the piston rod of the hydraulic cylinder at the tip to stop the slide. With this in place, operate the hydraulic cylinder and place the tip of the piston rod against the stopper to stop the supply of hydraulic pressure to the hydraulic cylinder, then release the pressure from the cushion and move the slide using the pressure from the balance cylinder to return to that moving state. The idea is to adjust the pressure in the balance cylinder accordingly. Therefore,
In this case as well, a hydraulic cylinder must be installed between the crown and the slide in addition to the balance cylinder.

As mentioned above, in all conventional slide counter balancer pressure adjustment devices, in addition to the balance cylinder, a position detection mechanism and a hydraulic cylinder must be provided between the crown and the slide, and these are connected to other parts. There is a problem in that it obstructs the arrangement of the parts, and furthermore, it makes assembly, disassembly, etc. difficult.

The present invention aims to solve these problems and provide a pressure adjustment device for a slide counter balancer that does not require a pressure adjustment mechanism other than a balance cylinder between the crown and the slide. .

Therefore, the present invention includes a detection cylinder in which the tip of the piston rod itself of the balance cylinder is the piston rod and is attached to the slide, and a pressure supply means for supplying pressure to the detection cylinder to raise the slide with the piston rod in a fixed state. , a detector that outputs an output signal when the slide moves up a predetermined stroke by supplying pressure to the detection cylinder; a lock mechanism that fixes the piston rod to the balance cylinder using the output from the detector; The present invention is characterized in that a release mechanism is provided that stops the pressure supply of the pressure supply means during output and gradually reduces the pressure of the detection cylinder.

When using this, first, place the slide at the top dead center, increase the pressure in the balance cylinder, and raise the slide by the amount of the gap to bring the slide to the highest position. Next, fluid pressure is supplied to the detection cylinder to push down the piston rod of the balance cylinder against the upward force of the piston. The detector is operated by the lowering of the piston rod, and at the same time the lock mechanism is operated to fix the piston rod of the balance cylinder. Next, the pressure supply to the detection cylinder is stopped, and the pressure is gradually reduced by the release mechanism. This reduced pressure causes the slide to descend, rendering the detector inoperable and
Depressurization by the release mechanism of the detection cylinder is also stopped. The push-up force exerted by the detection cylinder when the detector becomes inactive becomes the desired balance force of the balance cylinder. Therefore, the pressure of the balance cylinder can be set by calculating the air pressure that can generate this push-up force.

Next, details of the present invention will be explained with reference to illustrated embodiments.

In FIG. 1, a press machine 1 includes a crown 2,
It has a bed 3, and a slide 4 can freely slide between the beds. Reference numeral 5 denotes a bolster, in which an upper die 6 is attached to the slide 4 and a lower die 7 is attached to the bolster 5.

Two balance cylinders 8 are provided facing the sides of the crown 2. A piston rod 10 connected to the piston 9 of the balance cylinder 8 is extended to a bracket 11 of the slide 4, and is attached to this bracket 11 by a detection mechanism 13, which will be described later. Further, a locking mechanism 12 for fixing the piston rod 10 is attached to the bottom surface of the balance cylinder 8. The balance cylinder 8 is piped so that pressure is applied from an air tank 15. The pressure in this air tank 15 is automatically adjusted by a regulator valve 14 operated by a servo motor.

The lock mechanism 12 and the detection mechanism 13 are as shown in FIG.
As shown in the figure, it is composed of a plurality of cylinders 17 each having a piston 18 that reciprocates in a direction perpendicular to the axial direction of the piston rod 10. By supplying pressure to the cylinders, the piston rod 1
This is a structure that fixes 0. Note that the cylinder 1
7 is supplied with pressure from a pump 19 operated by a motor 22. 20 is a release valve that removes this pressure and opens the piston rod 10;
It is operated by a solenoid valve 21.

The detection mechanism 13 is connected to the bracket 1 of the slide 4.
A detection cylinder 23 fixed to 1 and a detector 25
It is composed of: This detection cylinder 2
The piston rod 10 of the balance cylinder 8 itself is used as a piston rod, and a piston 24 provided at the tip thereof is slidably housed in the piston 3.
The detector 25 is attached to the end of the detection cylinder 23 and is constituted by a limit switch that is turned on when the tip of the piston rod 10 protrudes from the detection cylinder 23.

The detection cylinder 23 is piped so that fluid pressure is supplied from a pump 26 connected to the motor 22, and a release valve 27 is attached to the pipe to gradually release the pressure. A servo motor 28 for changing pressure is connected to the release valve 27, and a solenoid valve 29 for unloading is also connected separately.

The pressure adjustment according to this embodiment having the above configuration is as follows. First, with the slide 4 at the top dead center, the regulator 14 is operated by the servo motor 16, and the pressure in the tank 15 is maximized to maximize the pressure in the balance cylinder 8. Therefore, the piston rod 10 is pulled up, and the gaps in each structure of the slide are also raised, and the slide 4 is lifted up.
is completely raised. Next, the servo motor 28
to close the release valve 27, operate the motor 22, operate the pump 26, and open the detection cylinder 23.
Maximize the pressure. The piston rod 10 is pushed down by the pressure supplied to the detection cylinder 23 against the upward force of the piston 9, whereby the piston rod 10 protrudes from the detection cylinder 23 and activates the detector 25.

The operation of this detector 25 causes the electromagnetic valve 21 to operate and the release valve 20 to turn off, thereby turning off the pump 1.
A pressure of 9 is applied to the locking mechanism 12 to operate it and the piston rod 10 is fixed. At the same time, the servo motor 28 is operated to gradually open the release valve. Then, the pressure in the detection cylinder 23 gradually decreases and the slide 4 descends. As the slide 4 descends, the detector 25 returns to its non-operating state, stopping the operation of the servo motor 28 and turning off the lock mechanism 12. Unlock. The pressure inside the detection cylinder 23 at this time becomes an appropriate force for pushing up the slide 4.

Therefore, the pressure in the balance cylinder 8 is adjusted by detecting the pushing up force by the detection cylinder 23 with a pressure gauge. The pressure is adjusted by regulating the regulator valve 14 by a servo motor 16. As described above, when the solenoid valve 21 returns to its original state due to the detector 25 being turned off, the release valve 20 operates to release the pressure of the pump 18, so that the lock mechanism 12 opens the piston rod 10.

After adjusting the air pressure of the balance cylinder 8, the press is operated with the lock mechanism 12 in the released state and without supplying fluid pressure to the detection mechanism 13.

As described above, the present invention utilizes the piston rod itself of the balance cylinder to configure the detection cylinder, and also provides the balance cylinder with a lock mechanism for fixing the piston rod, and supplies air pressure to the balance cylinder at the top dead center of the slide. At the same time, in this state, the detection cylinder is operated to lower the piston rod, and at the same time, the piston rod is fixed by a locking mechanism, and the pressure in the detection cylinder is gradually lowered by a release valve to lower the slide. Since the pressure in the detection cylinder at the position where the detector becomes inactive is used as the pressure in the balance cylinder, the appropriate balance pressure can be set in a short time without having to weigh the weight of the upper mold in advance. Since both the locking mechanism and the detector can be installed along the piston rod of the balance cylinder, there is no need to install anything extra between the crown and the slide, making it possible to form each member into a unit. This has the effect of simplifying work during installation and disassembly.

[Brief explanation of the drawing]

Figure 1 is a front view of a press machine equipped with a pressure adjustment device for the slide counter balancer of the present invention;
The figure is a diagram showing the state of the balance cylinder and air piping related thereto, and FIG. 3 is a sectional view taken along the line AA in FIG. 2. 1...Press machine, 2...Crown, 3...Bed,
4...Slide, 5...Bolster, 6...Upper die, 7...Lower die, 8...Balance cylinder, 9...Piston, 10
...Piston rod, 11...Bracket, 12...Lock mechanism, 13...Detection mechanism, 14...Regulator valve, 15...Air tank, 16...Servo motor, 17...Lock cylinder, 18...Lock piston, 19...Pump, 20...Release valve, 21
...Solenoid valve, 22...Motor, 23...Detection cylinder,
24...Detection piston, 25...Detector (limit switch), 26...Pump, 27...Release valve,
28...Servo motor.

Claims (1)

[Claims] 1. A device for adjusting the air pressure of a counter balancer connected to a slide of a press machine and provided in a press machine to urge the slide upward, which accommodates a detection piston provided at the tip of a piston rod of a balance cylinder and an attached detection cylinder; a pressure supply means for supplying fluid pressure to the detection cylinder to lower the piston rod of the balance cylinder against the upward force of the counter balancer; a detector that issues an output signal when the stroke is lowered; a lock mechanism that fixes the piston rod to the balance cylinder using the output from the detector; and a lock mechanism that similarly stops the pressure supply from the pressure supply means during output from the detector. 1. A pressure adjustment device for a slide counter balancer in a press machine, comprising: a release mechanism that gradually reduces pressure in a detection cylinder;