JP4050183B2 - Hydraulic press and molding method thereof - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a hydraulic press and a forming method thereof in the press field.
[0002]
[Prior art]
Conventionally, a normal hydraulic press has been press-molded so that a pre-fill valve is provided in order to descend the slide at a high speed, and oil in an oil tank mounted on the crown portion is filled into a pressure cylinder.
[0003]
However, in order to fill the pressurized cylinder from the oil tank, a large amount of hydraulic oil must be circulated through the prefim valve, so the oil tank must be set to a predetermined large capacity, and the piping capacity is increased accordingly. It takes a long time to fill the pressurized cylinder from the oil tank.
[0004]
[Prior art documents]
Therefore, a prior patent search was conducted for an oil tankless hydraulic press. As a result, JP-A-9-57500 was searched.
[0005]
Japanese Laid-Open Patent Publication No. 9-57500 proposes eliminating back pressure and an oil hammer according to changes in all ram speeds and ram strokes.
[0006]
[Problems to be solved by the invention]
In the above publication, no pre-fill valve or oil tank is connected to the pressure cylinder of the ram, but it is adjusted by connecting a piston-type accumulator to the return line of the pressure cylinder, which requires complicated control. It is very questionable whether it can be applied to a long stroke, high output hydraulic press.
[0007]
[Means for Solving the Problems]
The present invention has been made in view of the above points, and in order to solve the above problems, as a pressurizing cylinder of a hydraulic press, a large output main cylinder is connected to a small output sub-cylinder, The top and bottom hydraulic effective cross-sectional areas, which are the upper and lower surfaces of the main cylinder piston, are approximately equal, and the upper and lower rods protrude from the upper and lower surfaces of the piston, respectively. A conduction control valve is provided in the hydraulic circuit so that the hydraulic oil on the bottom side can be cut off, and when the slide descends at high speed, the hydraulic oil is conducted from the bottom side of the piston of the main cylinder to the top side so that the slide descends at high speed. The hydraulic fluid between the lower side and the upper side of the piston of the main cylinder is cut off when pressurizing the slide, and the upper side of the piston of the main cylinder is pulled back when the slide is pulled back. A hydraulic press molding method for pulling back the slide conducting hydraulic fluid to the lower surface side from the side, is formed by interior the sub cylinder of small output rod on the main cylinder of the large output of the pressure cylinder, First, the hydraulic fluid conduction control valve of the main cylinder is opened and the sub cylinder is driven to descend at a high speed, the slide is rapidly lowered to the pressurization position, and then the conduction control valve is closed and the piston of the main cylinder is closed. Hydraulic pressure characterized by introducing a hydraulic oil of a predetermined pressure into the upper surface side and performing pressure molding, and then opening the conduction control valve again after the pressure molding to drive the sub cylinder upward to raise the slide at a high speed It is in providing a press and its shaping | molding method.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The hydraulic press and the molding method thereof according to the present invention are formed by connecting a small output sub-cylinder to a high output main cylinder as a pressurizing cylinder of the hydraulic press, The bottom side hydraulic effective cross-sectional area is approximately the same, and the upper and lower rods protrude from the top and bottom sides of the piston, and the hydraulic oil on the top and bottom sides of the piston can be cut off. A continuity control valve is installed, and when the slide descends at high speed, hydraulic oil is conducted from the lower surface side to the upper surface side of the piston of the main cylinder so that the slide descends at high speed. The hydraulic fluid is cut off from the lower surface side to the upper surface side, and the hydraulic oil is conducted from the upper surface side to the lower surface side of the piston of the main cylinder when the slide is pulled back. Te to pull back the slide a hydraulic press molding method, formed by interior the sub cylinder of small output rod on the main cylinder of the large output of the pressure cylinder, first hydraulic fluid conduction control valve of the main cylinder Open the sub cylinder and drive the lower cylinder at a high speed to lower the slide to the pressurization position. Then, when it reaches the pressurization position, close the continuity control valve and introduce hydraulic oil at a predetermined pressure to the upper surface of the piston of the main cylinder. Then, the pressure forming is performed, and after the pressure forming, the above-mentioned conduction control valve is opened again, and the sub cylinder is lifted to raise the slide at a high speed.
[0009]
As shown in FIGS. 1A and 1B, the hydraulic press 1 has a bed 3 disposed at the lower part of the left and right frames 2 that are lightened by overlapping steel materials, and a slide 4 that faces the bed 3 at the upper part thereof. The slide 4 is disposed on the upper ends of the left and right frames 2 without hydraulic oil tanks, and can be hydraulically controlled by the pressurizing cylinder 5 based on the required press motion curve, and press-molded. ing.
[0010]
The pressurizing cylinder 5 is connected to a main cylinder 6 having a large output and a sub-cylinder 7 having a small output as shown in FIGS. 1 to 3, and in particular, the top side of the main cylinder 6 on the non-sliding side and the bottom of the sliding side. The hydraulic effective cross-sectional area on the side is made substantially equal so that the hydraulic oil in the main cylinder 6 is used effectively.
[0011]
For example, on the top side and the bottom side of the main cylinder 6, an upper rod 8 and a lower rod 9 are respectively provided on the upper and lower surfaces of the piston 10 as shown in FIGS. And the same effective hydraulic cross-sectional area of the top side of the main cylinder 6 on the upper side of the main cylinder 6 and the bottom side of the lower side of the slide side, and hydraulic oil on the upper and lower surfaces of the piston 10 in the main cylinder 6. The conduction control is appropriately performed via the conduction control valve 11.
[0012]
If the effective hydraulic cross-sectional areas of the upper surface side and the lower surface side of the piston 10 of the main cylinder 6 are made equal, the hydraulic oil in the main cylinder 6 can be moved and used in the main cylinder 6 as long as there is no leakage of the hydraulic oil. It is possible to circulate through the power source 12 and eliminate the need to fill the main cylinder 6 with hydraulic oil by installing an oil tank at the top of the hydraulic press and connecting a prefill valve as in the prior art.
[0013]
In this way, it is preferable to make the effective hydraulic cross-sectional areas of the upper surface side and the lower surface side of the piston 10 of the main cylinder 6 equal, but by adding an oil source of the hydraulic source 12 described below or an accumulator within a range that does not cost much. For example, the effective hydraulic cross-sectional area of the upper surface side and the lower surface side of the piston 10 of the main cylinder 6 can be set to a ratio of 0.9 to 1.0.
[0014]
As such a conduction control valve 11 of the main cylinder 6, for example, as shown in FIG. 3, a two-position hydraulic control valve can be used, and check valves 13 and 14 can be connected. Reference numeral 15 denotes a support frame for the sub cylinder 7.
[0015]
Further, as shown in FIGS. 2 and 3, a part of the sub-cylinder 7 is provided on the upper rod 8 of the main cylinder 6 so as to drive the piston 10 of the main cylinder 6 up and down at high speed. In particular, it is preferable to install the auxiliary cylinder 7 in the upper rod 8 of the main cylinder 6 so that the height of the pressure cylinder 5 can be reduced and the hydraulic press 1 can be downsized.
[0016]
The control cylinder is not directly used for the main cylinder 6 and the sub cylinder 7 of the pressurizing cylinder 4 of the hydraulic press 1 and the knockout cylinder 16 of the bed 3 formed as described above, as shown in FIGS. It is connected to hydraulic sources 12, 17, 18 of a predetermined capacity of a so-called DDV type hydraulic servo control capable of controlling the hydraulic pressure of the drive, so that press forming can be performed by the hydraulic press 1 without an oil tank as described above. Is.
[0017]
FIG. 5 shows the press stroke of the slide 4 by the pressurizing cylinder 5. The conduction control valve 11 is in a conducting state, and the sub cylinder 7 is driven to descend at a high speed via the hydraulic source 17, and the piston 10 in the main cylinder 6 is driven. The bottom side hydraulic oil is moved to the top side which is the upper surface side through the conduction control valve 11 to descend the slide 4 at a high speed, and the conduction of the conduction control valve 11 is closed at a predetermined position of the slide 4. As a state, the hydraulic oil is pressurized and supplied from the hydraulic source 12 to the top side which is the upper surface side of the main cylinder 6 and press-molded. After the pressure molding, the conduction control valve 11 is opened again and the sub-cylinder 7 is raised at high speed. When driven, the hydraulic oil on the top side in the main cylinder 6 moves to the bottom side through the conduction control valve 11 so as to raise the slide 4 at a high speed.
[0018]
FIG. 6 shows another embodiment of the pressurizing cylinder 5 in which the upper and lower surfaces of the piston 10 and logic valves can be used. Further, as shown in FIG. 7, the rod 20 of the sub-cylinder 7 can be coupled to the upper rod 8 of the main cylinder 6. Even in this way, the above-described function can be achieved. It is to be noted that, similarly to the main cylinder 7, it is preferable that the rods protrude from the upper and lower surfaces to make the effective hydraulic cross-sectional area the same at the upper and lower surfaces of the piston.
[0019]
Furthermore, the above-described conduction control valve 11 can be easily attached to and detached from a circuit block 22 having a hydraulic conduction circuit 21 opened at the side of the pressure cylinder 4 as shown in FIGS. 1 to 3, 6, and 7. It is preferable to allow circuit connection.
[0020]
In the above description, the oil tankless hydraulic press has been described. However, the present invention is also applicable to a hydraulic tank installed and supplying hydraulic pump discharge oil to the main cylinder, sub cylinder, and knockout cylinder via the hydraulic control valve. The present invention can be applied based on the purpose, and can also be applied to an apparatus that can be connected to an accumulator having a predetermined capacity.
[0021]
【Example】
1 to 5 show an embodiment of the present invention. The hydraulic press 1 is configured by attaching a bed 3 and a pressure cylinder 5 on the upper and lower sides of a frame 2 on both sides of which steel materials of 95 mm thickness and 65 mm thickness are appropriately overlapped and joined, and an oil tank is attached to a so-called crown portion. Without being provided, the slide 4 can be driven up and down to perform press molding.
[0022]
In particular, the pressurizing cylinder 5 connects the high-output main cylinder 6 and the small-output sub-cylinder 7 as described above with reference to FIGS. The upper rod 8 and the lower rod 9 having the same diameter are provided so as to make the effective hydraulic cross-sectional areas of the slide side top side and the slide side bottom side equal.
[0023]
Also, as shown in FIGS. 4 (a) and 4 (b), oil pressure sources 12, 17, and 18 of a so-called DDV type hydraulic servo control are respectively provided to the main cylinder 6, the sub cylinder 7 and the knockout cylinder 16 of the pressure cylinder 5. It is connected so that press molding can be performed by a hydraulic press 1 without an oil tank.
[0024]
That is, for example, before the pressurizing cylinder 5 is driven in advance, hydraulic oil is filled in the top side and the bottom side of the upper and lower surfaces of the piston 10 in the main cylinder 6 of the pressurization cylinder 5, and the conduction control valve as shown in FIG. When the sub-cylinder 7 is driven at a high speed downward via the hydraulic pressure source 17 in the conductive state, the bottom side hydraulic oil in the main cylinder 6 moves to the top side through the conduction control valve 11 and moves the slide 4 at a high speed. Can descend.
[0025]
Then, the conduction of the conduction control valve 8 is closed at a predetermined position of the slide 4, and hydraulic oil is pressurized and supplied from the hydraulic source 12 to the top side of the main cylinder 6 and press-molded.
[0026]
After the pressure molding, when the conduction control valve 11 is opened again and the sub cylinder 7 is driven to rise at a high speed, the hydraulic oil on the top side in the main cylinder 6 moves to the bottom side through the conduction control valve 11 and slides. 4 can rise at high speed.
[0027]
Thus, the hydraulic oil in the main cylinder 6 can be used by moving in the main cylinder 6 and circulated through the hydraulic power source. It is not necessary to connect and fill the main cylinder 6 with hydraulic oil, so that a small amount of hydraulic oil can be used, and equipment can be reduced, and press molding can be performed.
[0028]
Also, as shown in FIGS. 1 to 3, by placing the sub cylinder 7 in the upper rod 8 of the main cylinder 6, the height of the pressurizing cylinder 5 can be lowered and the hydraulic press 1 can be downsized. preferable.
[0029]
FIG. 6 uses a logic valve of another embodiment of the conduction control valve 11 of the main cylinder 6 of the pressurizing cylinder 5 of the present invention, and can be operated as described above.
[0030]
Although various embodiments have been described, appropriate modifications can be implemented based on the spirit of the present invention.
[0031]
【The invention's effect】
As described above, in the present invention, the hydraulic oil of the main cylinder having a large output can be used by moving in the main cylinder, and it is necessary to fill the main cylinder with the hydraulic oil via the prefill valve as in the past. The press can be formed by controlling the conduction control valve of the main cylinder. By filling hydraulic oil in the upper and lower surfaces of the piston of the main cylinder in advance, the hydraulic oil in the main cylinder can be moved as described above, or can be circulated and press-formed through a hydraulic power source. In particular, the upper cylinder of the high-pressure main cylinder of the above-mentioned pressurization cylinder is formed with a small-output sub-cylinder, so the height of the pressurization cylinder can be lowered and the hydraulic press can be downsized. This is preferable.
[0032]
And, as described above, the pressure cylinder can be lowered at high speed through the sub-cylinder whose height is lowered, and can be press-formed through the main cylinder, and the slide can be raised at high speed via the sub-cylinder. .
[0033]
Also, the hydraulic effective cross-sectional area of the upper and lower surfaces of the piston of the main cylinder should be a ratio of 0.9 to 1.0, and drive control is performed by connecting a direct drive hydraulic pressure control type hydraulic power source to the pressure cylinder. Thus, the hydraulic oil in the main cylinder can be press-molded with a small amount of replenishment.
[0034]
In addition, since the hydraulic oil from the main cylinder with high output can be used by moving in the main cylinder or circulated through the hydraulic power source, an oil tank is installed on the upper part of the hydraulic press as in the past, and pre-filling is performed. It is no longer necessary to connect the valve and fill the main cylinder with hydraulic oil, so that a small amount of hydraulic oil can be used and equipment can be reduced.
In particular, the upper cylinder of the high-pressure main cylinder of the above-mentioned pressurizing cylinder is formed with a small-output sub-cylinder, so the height of the pressurization cylinder can be lowered and the hydraulic press can be made compact. This is preferable.
[0035]
In particular, the hydraulic oil in the main cylinder can be moved or circulated as described above by equalizing the effective hydraulic cross-sectional areas of the upper surface and the lower surface of the piston of the main cylinder.
[Brief description of the drawings]
FIG. 1 is a front view (a) and a side sectional view (b) of an embodiment of the present invention;
FIG. 2 is a side cross-sectional view for explaining the pressure cylinder part of the above,
FIG. 3 is a diagram for explaining the function of the pressure cylinder unit,
FIG. 4 is a plan layout diagram (a) and an operation explanatory diagram (b) of the hydraulic pressure source;
FIG. 5 is a diagram for explaining press molding by the pressure cylinder,
FIG. 6 is a side sectional view for explaining another embodiment of the pressure cylinder part of the above.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Hydraulic press 4 ... Slide 5 ... Pressure cylinder 6 ... Main cylinder 7 ... Sub cylinder 8 ... Upper rod 9 ... Lower rod 10 ... Piston 11 ... Conduction control valve 12, 17, 18 ... Hydraulic source

Claims (4)

As a pressurizing cylinder of a hydraulic press, a large output main cylinder is connected to a small output sub cylinder, and the top and bottom hydraulic effective cross-sectional areas, which are the upper and lower surfaces of the piston of the high output main cylinder, are formed. The upper rod on the top and bottom sides and the lower rod on the upper and lower surfaces of the piston project approximately equally, and a conduction control valve is provided in the hydraulic circuit to cut off the hydraulic oil on the upper and lower surfaces of the piston. When the slide is moved at a high speed, hydraulic oil is conducted from the lower surface side to the upper surface side of the piston of the main cylinder so that the slide is moved down at a high speed. Oil that cuts off the hydraulic fluid of the main cylinder and that pulls the slide back by conducting hydraulic fluid from the upper surface side to the lower surface side of the piston of the main cylinder when the slide is pulled back. A press molding method,
A high-power sub-cylinder is built in the upper rod of the high-power main cylinder of the pressure cylinder,
First, open the hydraulic cylinder conduction control valve of the main cylinder and drive the sub cylinder to descend at high speed to descend the slide to the pressurization position at high speed.
Next, when the pressure position is reached, the conduction control valve is closed and a predetermined pressure of hydraulic oil is introduced into the upper surface of the piston of the main cylinder to perform pressure molding,
Then, after press molding, the above-mentioned conduction control valve is opened again to drive the sub-cylinder upward to raise the slide at high speed.   The hydraulic effective cross-sectional area of the upper and lower surfaces of the piston of the main cylinder is a ratio of 0.9 to 1.0, and the drive control is performed by connecting a direct drive hydraulic pressure control type hydraulic power source to the above pressure cylinder. A hydraulic press molding method characterized. As a pressurizing cylinder of a hydraulic press , a small output sub-cylinder is connected to a high output main cylinder, and the effective hydraulic cross-sectional areas of the top and bottom sides, which are the upper and lower surfaces of the piston of the high output main cylinder, are almost equal. The upper and lower rods are projected on the upper and lower surfaces of the piston on the top and bottom sides , respectively, so that the hydraulic oil on the upper and lower surfaces of the piston can be conducted.
A high-power sub-cylinder is built in the upper rod of the high-power main cylinder of the pressure cylinder,
When the slide descends at high speed, hydraulic oil is conducted to the upper and lower surfaces of the piston so that the slide descends at high speed via the sub cylinder. Oil conduction is cut off, and the hydraulic control circuit is connected to the hydraulic circuit of the main cylinder so that the hydraulic oil is conducted from the upper surface to the lower surface of the piston when the slide is pulled back, and the slide is pulled back at high speed via the sub cylinder. Arranged,
An oil tankless hydraulic press, wherein the pressurizing cylinder is connected to a direct drive hydraulic pressure control type hydraulic power source to control driving.   The oil tankless hydraulic press according to claim 3, wherein the effective hydraulic sectional areas of the upper surface side and the lower surface side of the piston of the main cylinder are equal.

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