JPH0246979Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] The present invention relates to a press machine.

[Conventional technology and its problems]

In presses that perform plastic working on plastic products and other materials, the upper and lower molds are brought together to perform molding, and then the mold release process begins. When releasing the mold, for example, if the molded product is extremely thin, if the upper mold does not rise in equilibrium, the molded product may be damaged or deformed, reducing the yield, or the mating part of the mold may be damaged. etc., resulting in shortened mold life and increased mold cost.

In addition, when performing in-mold molding, it is necessary to slightly raise the upper mold to form an in-mold cavity between it and the lower mold once the main product has been molded. In this case as well, the same problem as above occurs.

Therefore, during mold release or similar processes, it is desirable that the slide with the upper mold attached be able to rise at a slow speed while maintaining balance, but conventional presses have not been able to meet this requirement. .

[Means for solving problems]

This invention was devised after repeated research in view of the above-mentioned circumstances, and its purpose is to create a press machine that can perform highly accurate equilibrium mold release with a relatively simple and compact structure. It is about providing.

In order to achieve the above object, the present invention includes a spacing cylinder having the same capacity and having a piston with the same stroke at at least the corners of the slide side and the bed side, and a pair of spacing cylinders with which the pistons abut. A plurality of sets of receiving members are arranged facing each other, and the pressure oil supply ports of the separation cylinders are connected to the pressure oil discharge sides of the respective sub-cylinders of the same capacity by piping, and the rams of each sub-cylinder are connected to the common source cylinder. It was made to work.

[Effect]

If the common cylinder is operated with the receiving member and each spacing cylinder in contact, the piston of this cylinder moves forward, and each ram in each sub-cylinder also moves forward by the same exact stroke, causing each ram to move forward. As a result, the same amount of oil in each sub-cylinder flows into each spacing cylinder through the respective piping.

Therefore, the piston of each spacing cylinder protrudes exactly the same amount and presses against the receiving member. The reaction force caused by this causes the slide to rise at a very low speed, but since the back pressure of each separation cylinder is the same, even if the resistance of each part of the slide differs, only an extremely small tilt due to the compression of the pressure oil occurs, and the slide rises exactly.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 to 4 show an embodiment of a press machine according to the present invention, in which 1 is a press frame, 2 is a bed, and 3 is a slide operated by a main cylinder 4. FIG.

5, 5 are receiving members installed vertically at at least four corners of the bed 2 or slide (3);
In the illustrated example, a plurality of sets (four sets in the figure) of adjusting screws are used as the elevating body. In the embodiment shown in FIG. 2, non-elevating bodies such as blocks are used and are fixed on the bed 2.

Reference numeral 6 denotes a spacing cylinder which is arranged and fixed at a position corresponding to the axial direction of the receiving members 5, 5 via brackets 61, 61.

In FIG. 1, each adjusting screw 5,
5 is a female screw block 20, 20 installed on bed 2.
At the same time, drive rods 21, 21 are inserted into the center of the adjuster screws 5, 5, and are keyed to allow the adjustment screws to move up and down. The synchronous shaft 22 is engaged with a synchronous cylinder placed horizontally through bevel gears 23, 23', and is rotated by a reversible drive motor 24 such as a DC servo motor. If necessary, a high speed drive motor 24' is also used, and the inching cylinder 25 is adapted to be slightly driven.

A thrust bearing 51 is provided at the upper end of the adjusting screws 5, 5 to reduce resistance due to contact rotation with the spacing cylinder.

In both the embodiments shown in FIGS. 1 and 2,
The spacing cylinders 6, 6 are each configured to have the same capacity,
Pistons 7, 7 with the same stroke are inserted through the opening in the lower surface so as to be able to move forward and backward, and the piston head is always urged upward with a predetermined pressure by springs 8, 8 interposed between the lower surface and the bottom of the cylinder. .

In this embodiment, four sets of spacing cylinders are used, and the pressure oil supply port 60 for the piston head of each spacing cylinder 6a, 6b, 6c, and 6d is provided with piping having the same specifications such as diameter and length. 9a, 9b, 9c,
9d is connected, and these pipes 9a, 9b, 9c,
The rear end of 9d is the sub-cylinder 1 arranged and fixed elsewhere.
It is connected to the discharge side of 0a, 10b, 10c, and 10d.

Sub cylinders 10a, 10b, 10c, 10d
The sub-cylinders 10a, 10b, 10c, and 10d are each divided into parts with the same capacity, and a common source cylinder 11 is disposed behind the sub-cylinders 10a, 10b, 10c, and 10d to operate these sub-cylinders synchronously and by the same amount.

The common source cylinder 11 is provided with a piston 12 that is movable forward and backward by a hydraulic circuit including a three-way switching valve 13, a flow rate adjustment valve 14, and a relief valve 15.

In FIG. 3, sub cylinders 10a, 10b, 10
c and 10d are arranged in parallel, and a common head 1 is provided at the tip of the piston 12 of the common source cylinder 11.
6 is fixed, and each spacing cylinder 6a,
A ram 17 of the same diameter with a volume corresponding to the required stroke (for example, 5 mm) of 6b, 6c, and 6d.
a, 17b, 17c, 17d have their proximal ends fixed,
The tip side is connected to each of the sub-cylinders 0a and 10, respectively.
b, 10c, and 10d.

Further, in the embodiment shown in FIG. 4, each sub-cylinder 10
a, 10b, 10c, 10d are arranged in series, and the same diameter rams 17a, 17b, 17c,
17d is provided. The piston 12 of the common source cylinder 11 is in contact with or connected to the head of the same-diameter ram 17a of the sub-cylinder 10a at the rear end, and the tip of the piston of the same-diameter ram 17a penetrates the partition wall 100 to the next same-diameter ram 17a. It has reached the head of the diameter ram 17a. Similarly, the rear of each same-diameter ram is pressed by the piston of the same-diameter ram in the rear stage, and the same-diameter ram 17d of the sub-cylinder 10d at the tip is pushed backward by the spring 19 inscribed in the outer casing 18. is being energized.

In other drawings, 26 is an encoder, 27
is a position controller.

Next, an example of the use of the present invention will be described with reference to FIGS. 1 and 3. When processing is performed by attaching upper die a and lower die b to slide 3 and bed 2, respectively, set the preload position according to the die height,
Activate the drive motor. As a result, all adjusting screws 5, 5 are raised and lowered by the same amount at a constant speed by the synchronized shaft 22 and the drive shafts 21, 21.
When the set position is reached, it is detected by the encoder 26, and the position controller 27 stops the drive motor 24 from operating.

At this time, the pistons 7, 7 of the spacing cylinders 6, 6 are kept at the upper limit by the springs 8, 8, and when the slide 3 is lowered by the operation of the main cylinder, the tip of the piston and the adjuster screw are connected as shown in Fig. 5A. The end surfaces of the u 5, 5 come into contact and preload is started. Preload speed is adjusted screw 5,5
can be freely adjusted by adjusting the lowering speed of the drive motor 24, that is, the rotation speed of the drive motor 24.

When the preload is completed, all adjusting screws 5, 5 are moved by the drive motor 24 as shown in FIG.
It further descends and stops at the set position. During this time, the slide 3 is lowered by the main cylinder until the pistons 7, 7 touch the tips of the adjusting screws 5, 5, and as a result, the upper mold a and the lower mold b
is pressurized and the desired processing, such as FRP molding, is performed.

After the molding process is completed, in order to release the pressure and release the mold, the pistons 7, 7 of the spacing cylinders 6, 6 are in contact with the adjusting screws 5, 5, and the common source cylinder is 11 3-way switching valve 13
This activates SOL1 of
The piston 12 shifts from the state shown in FIG. 3 to a forward stroke, and the common source head 16 also moves forward by the same stroke. As this common head 16 advances, each of the same diameter rams 17a, 17b, 17c, 1 fixed thereto
7d is the sub cylinder 10a with equal stroke;
10b, 10c, 10d and the oil contained in each cylinder is transferred to each pipe 9a, 9b, 9c,
9d, the same amount of oil is sent to the corresponding spacing cylinders 6, 6, and as a result, each piston 7, 7
Extrudes by exactly the set stroke.

Since the adjustment screws 5, 5 are strongly pressed downward by the protrusion of each piston 7, 7, the fifth
As shown in Figure C, a mold release force is applied to the slide 3 due to the reaction force, and the upper mold a and the lower mold b are separated. The separation speed at this time can be freely set, for example, from 0.5 to 5 mm by controlling the oil supply to the common source cylinder 11.

The adjusting screws 5, 5 are matched to the set height by the synchronizing shaft 22 and the drive shaft 21, 21, and the protruding length and back-up pressure of the respective spacing cylinders 6, 6 are also matched. Therefore, the slide 3 is lifted while maintaining a highly accurate balanced state. Therefore, even if the resistance during mold release differs at each point of the upper and lower molds, it will never exceed an extremely small slope due to the compression of the pressure oil, and even if the molded product is extremely thin, this will not be the case. There will be no damage or deformation, and no galling of the molds.

After demolding, the slide 3 is raised to its upper limit by a push-up or pulling cylinder (not shown). At the same time, SOL2 of the three-way switching valve 13 is activated in preparation for the next cycle.
As a result, the piston 12 of the common source cylinder 11 retreats, and the common base 16 causes each of the same diameter rams 17,
17 retreats by the same stroke, and the pressure oil of each spacing cylinder 6, 6 is transferred to piping 9a, 9b, 9c,
9d and the same amount to each sub cylinder 10a, 10.
Return to b, 10c, 10d. Therefore, the respective pistons 7, 7 are held by the springs 8, 8 at the rising limit of the spacing cylinders 6, 6.

In order to perform in-mold molding after molding, upper mold a
The same operation as above can be performed even when raising the mold by a small amount. In this case as well, the slide rises in equilibrium, creating a high-precision gap between the product and the bottom surface of the upper mold, which is necessary for in-mold molding. There is no variation in mold thickness.

And once the in-mold molding is finished,
The spacing cylinders 6, 6 are moved back to their upper limit, the adjusting screws 5, 5 are raised to the repressurizing position, and the slide 3 is slightly lowered. As a result, pressure is maintained with the same force as during pre-pressing, and in-mold molding is performed. After the molding is completed, the mold may be released as described above.

In addition, in the case of the oil feeding mechanism shown in FIG.
Same diameter rams 17a, 1 of 0a, 0b, 10c, 0d
Since the cylinders 7b, 17c, and 17d move in series with the same stroke, each of the spacing cylinders 6, 6 can operate accurately and achieve appropriate balanced mold release.

The embodiment shown in FIG. 2 is suitable for cases where die height adjustment of the upper and lower molds is not required, and equilibrium mold release can be performed simply and accurately.

The present invention is suitable for D-shaped plastic materials such as FRP, and is generally applicable to cases where a large force is required during mold release and an eccentric load is applied during mold release. Furthermore, it goes without saying that the relationship between the spacing cylinders 6, 6 and the adjusting screws 5, 5 may be reversed.

[Effect of idea]

According to the present invention described above, the simple and compact structure provides excellent effects such as the ability to accurately balance and raise the slide during mold release and similar operations.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing an example of a press machine equipped with a balance lifting device according to the present invention, Fig. 2 is a front view showing another embodiment of the invention, and Figs. FIGS. 5A to 5C are explanatory diagrams showing the control circuit of the spacing cylinder in the invention, and FIGS. 2... Bed, 3... Slide, 5, 5... Receiving member, 6, 6... Separation cylinder, 7, 7...
Piston, 9a, 9b, 9c, 9d...Piping, 1
0a, 10b, 10c, 10d...sub-cylinder,
11...Common source cylinder, 17a, 17b, 17
c, 17d... Same diameter ram.

Claims (1)

[Scope of utility model registration request] A plurality of pairs of spacing cylinders having the same capacity and having pistons with the same stroke, and receiving members paired with the spacing cylinders and abutted by the pistons are arranged facing each other at least at the corners of the slide side and the bed side, The pressure oil supply port of each separation cylinder is connected to the pressure oil discharge side of each sub cylinder having the same capacity through piping, and the ram of each sub cylinder is operated by a common source cylinder. press machine.