JPH0117394Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a continuous hoop forming machine.

(b) Conventional technology As a conventional continuous hoop molding machine, for example,
There is something like the one shown in the figure. Upper mold 14 attached to upper movable platen 10 and lower fixed platen 12, respectively
A hoop material 18 is supported at a predetermined tension between the upper and lower molds 16 by a tension device 22 on a hoop lift plate 20 and a guide roller 24. The ejector pin 26 is mounted on an ejector pin mounting plate 32. The ejector hydraulic cylinder 28 is connected to a solenoid valve 34. A flow regulator 36 is provided in an oil passage 35 through which hydraulic pressure is discharged when the ejector hydraulic cylinder 28 returns from the protruding position to the initial position. Note that a positioning pin 38 is provided on the upper surface of the lower mold 16 for fitting into a hole provided in the hoop material 18 to position it. The hoop material ejecting operation of this conventional continuous hoop forming machine is performed as follows. That is, when the molding is finished, the ejector pin 26 and the hoop lift plate 20
simultaneously rises, and the hoop material 18 and the hoop material 18
Push up the molded product. When the ejector pin 26 protrudes to a predetermined position, it stops, but the hoop lift plate 20 further rises to separate the molded product from the ejector pin 26. In this state, the solenoid valve 34 is set to a neutral state (that is, both the supply side and the discharge side of the ejector hydraulic cylinder 28 are closed), and the hoop material 18 is fed by a predetermined amount while the hoop lift plate 20 is kept pushed out. Next, the solenoid valve 34 is switched to the a side, and the ejector pin 26 and hoop lift plate 2 are
0 together. By doing this, the hoop material 18 is lowered onto the lower mold 16, and at this time the hoop material 18 is positioned by the positioning pins 38. Hoop material 1 by this positioning pin 38
In order to smoothly position the hoop material 18, it is necessary to lower the hoop material 18 slowly. For this reason, the flow of oil in the oil passage 35 is throttled by the flow passage controller 36 to slow down the operation of the ejector hydraulic cylinder 28.

(c) Problems to be solved by the invention However, with such conventional continuous hoop molding machines, as mentioned above, it was necessary to lower the hoop material gently and position it, so the time required for one molding cycle was shortened. The problem was that it was long.

(d) Means for solving the problem The present invention was developed by focusing on the above-mentioned problems in conventional continuous hoop molding machines. The hoop material is held as it is, and the positioning pin provided on the upper mold is used to position the hoop material during the mold closing operation, and the ejector pin mounting plate and hoop lift plate are pushed back to their initial positions during the mold closing operation. The purpose is to solve problems. That is, according to the present invention, the hydraulic ejector includes an ejector hydraulic cylinder,
an ejector rod that can be moved up and down by an ejector hydraulic cylinder; an ejector pin mounting plate that is equipped with an ejector pin that can eject the hoop material upward from the lower mold; and a hoop lift plate that holds the hoop material; and a return pin whose lower end is fixed to the hoop lift plate, and the ejector rod is configured to raise the ejector pin mounting plate to a predetermined protruding position and then further rise to raise the hoop lift plate to the hoop lifting position. The return pin has a length such that the upper end of the return pin is located above the upper surface of the lower mold when the hoop lift plate is in the hoop lifting position, and the ejector hydraulic cylinder corresponds to the hoop lifting position. A counterbalance valve is installed in the oil passage through which oil is discharged when returning to the initial position from the raised position. It is set so that it will not open due to the weight of the plate and the members provided integrally therewith, but will open when the mold closing force is applied from the upper mold via the return pin, and the hoop is attached to the upper mold. A positioning pin is provided that fits into a hole in the material to position the hoop material.

(E) Embodiments Hereinafter, embodiments of the present invention will be described based on FIG. 2 of the attached drawings.

A hoop material 18 is held by a tension device 22 and a guide roller 24 on a hoop lift plate 20 between an upper mold 14 and a lower mold 16 attached to the upper movable platen 10 and the lower movable platen 12, respectively. There is. Note that a return pin 25 is also provided on the hoop lift plate 20. The hoop material 18 can be fed in predetermined amounts by a feeder (not shown). A hoop material 18 is provided on the lower surface of the upper mold 14.
A positioning pin 38 is attached that fits into a hole provided in the hole to position it. The ejector pin 26 is connected to an ejector rod 30 which is axially movable by an ejector hydraulic cylinder 28.
The ejector pin mounting plate 32 is connected to the ejector pin mounting plate 32. In addition, the ejector pin mounting plate 32
The connection between the ejector rod 30 and the ejector rod 30 is not fixed, and the ejector rod 30 is configured so that the hoop lift plate 20 can be further raised after the ejector pin mounting plate 32 is raised to a predetermined position. Hydraulic cylinder 28 for ejector
The two chambers 28a and 28b are each connected to a solenoid valve 42 as shown. A counterbalance valve 44 is provided in the oil passage 35 that connects the chamber 28a and the solenoid valve 42. The counterbalance valve 44 is connected to the hoop lift plate 20 and the ejector pin mounting plate 32.
(i.e., the ejector hydraulic cylinder 28 can support these weights), but when a force greater than this is applied, it will open and allow oil to flow. It is set to . The solenoid valve 42 is
It is connected to a hydraulic power source 46 and a tank 48 as shown. Note that a flow rate controller 50 is provided between the hydraulic power source 46 and the solenoid valve 42. Note that the solenoid valve 42 is of a type that drains two oil passages in the neutral position.

Next, the operation of this embodiment will be explained.

When the molding is completed, the solenoid valve 42 is operated on the b side, hydraulic pressure is supplied to the chamber 28a, and the ejector rod 30 is raised. Therefore, both the hoop lift plate 20 and the ejector pin mounting plate 32 rise, and after the ejector pin 26 reaches a predetermined position, only the hoop lift plate 20 rises. By doing so, the hoop material 18 is pushed away from the ejector pin 26. In this state, solenoid valve 4
2 is set to off to set the neutral position. Even if the solenoid valve 42 is in the neutral position, the hoop lift plate 20 and the ejector pin mounting plate 32 will not fall due to their own weight because the counterbalance valve 44 is provided in the oil passage 35 connected to the chamber 28a. It will remain in the same position. In this state, the hoop material 18 is fed by a predetermined amount by a feeder (not shown). Next, the upper movable platen 10 is lowered to perform a mold closing operation. When the upper mold 14 contacts the hoop material 18, the positioning pin 38 attached to the upper mold 14 fits into the positioning hole provided in the hoop material 18, and the hoop material 18 is positioned. At the same time as the upper mold 14 contacts the hoop material 18, the upper mold 14 contacts the return pin 25,
Push down the hoop lift plate 20. As a result, the oil pressure in the chamber 28a of the ejector hydraulic cylinder 28 increases, and oil is discharged into the tank 48 through the counterbalance valve 44, so that the ejector rod 30 is lowered. That is, hoop lift plate 2
0 and the ejector pin mounting plate 32 are lowered together,
These return to their initial positions. By doing this, one cycle is completed. As described above, according to the present invention, there is no need to gently lower the ejector pin 26 to position the hoop material 18 on the lower mold 16, so the time required for one cycle can generally be shortened by 1.0 to 1.5 seconds. This makes it possible to improve molding efficiency.

(f) Effects of the invention As explained above, according to the invention, the above-mentioned configuration eliminates the need for the process of gently returning the hydraulic ejector, resulting in the effect of shortening the molding cycle time. Obtainable.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional continuous hoop molding machine, and FIG. 2 is a diagram showing a continuous hoop molding machine according to the present invention. 10...Upper movable plate, 12...Lower movable plate, 14...
... Upper mold, 16 ... Lower mold, 18 ... Hoop material,
20... hoop lift plate, 22... tension device, 24... guide roller, 25... return pin, 26... ejector pin, 28... hydraulic cylinder for ejector, 30... ejector rod,
32... Ejector pin mounting plate, 35... Oil path,
38...Positioning pin, 42...Solenoid valve, 44...Counter balance valve, 46...Hydraulic pressure source, 48...Tank, 50...Flow rate controller.

Claims (1)

[Scope of claim for utility model registration] Fixed lower mold 16 and upper mold 1 that can move up and down
In a continuous hoop forming machine that holds and molds the hoop material 18 between the hoop material 18 and the hoop material 4, and ejects the formed hoop material by a hydraulic ejector, the hydraulic ejector has an ejector hydraulic cylinder 28 and an ejector hydraulic cylinder. An ejector rod 30 that can be moved up and down with the handle, an ejector pin mounting plate 32 to which is attached an ejector pin 26 that can eject the hoop material upward from the lower mold, a hoop lift plate 20 for holding the hoop material, and a hoop lift. and a return pin 25 whose lower end is fixed to the plate, and the ejector rod is configured to raise the ejector pin mounting plate to a predetermined protruding position and then further rise to raise the hoop lift plate to the hoop lifting position. The return pin has a length such that the upper end of the return pin is located above the upper surface of the lower mold when the hoop lift plate is in the hoop lifting position, and the ejector hydraulic cylinder corresponds to the hoop lifting position. A counterbalance valve 44 is provided in the oil passage 35 through which oil is discharged when returning from the raised position to the initial position, and the counterbalance valve includes a hoop lift plate protruded by an ejector hydraulic cylinder, Although it does not open due to the weight of the ejector pin mounting plate and the members provided integrally therewith, it is set so that it opens when a mold closing force is applied from the upper mold via the return pin, and the upper mold A continuous hoop forming machine characterized in that a positioning pin 38 is provided for fitting into a hole in the hoop material and positioning the hoop material.