JP2002035994A - Booster and press forming apparatus with same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a booster and a press forming machine with it, which is able to put forth larger working force while ensuring comparatively large stroke. SOLUTION: A first cylinder 21 and a second cylinder 22, whose cross section is larger than the first one, are connectedly formed into one body, being aligned in the same axis. A first piston 23 and a second piston 24 are inserted and slid in the first cylinder and the second cylinder respectively. A projection 25, shorter in the axial direction than the stroke of the first piston, is mounted on the second piston. The projection is inserted in the first cylinder tightly but slidingly. The move of the first piston puts forth larger working force than that of the first piston to the second piston through the medium of liquid in the first cylinder and the second cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure intensifier including a liquid cylinder as a component and a press machine having the same. The present invention relates to a pressure increasing device capable of obtaining an operating force and a press working device provided with the same, for example, used for sheet metal working, punching of a sheet material, and the like.

[0002]

2. Description of the Related Art Conventionally, as a means for driving a movable die of a processing unit having a movable die and a fixed die in a press processing device, a hydraulic cylinder has been widely used, and a hydraulic cylinder has been widely used. In a press working apparatus driven by a hydraulic cylinder, when a large operating force is applied to a working unit, a pressure increasing means applying the principle of Pascal is applied.

FIG. 9 shows a conventional pressure increasing means.
It is explanatory drawing which shows an example. In FIG. 9, the hydraulic cylinder
100 has a plunger 101 and a piston 102 each.
Piston interposed and connected to piston 102
An operating force is applied to a predetermined processing unit by the rod 103.
It can be obtained. And the plunger 101 and
The cross-sectional area of the piston 102 is A₁, A_TwoThen
P on plunger 101 ₁If you give a certain force,
In the head 103_Two= P₁・ A_Two/ A₁Operating force
can get.

[0004]

According to the pressure boosting means as shown in FIG. 9 A be Solved by the Invention] By setting the ratio of A ₂ / A ₁ to a large, the operating force P ₂ of large become obtained. For example, the diameters of the plunger 101 and the piston 102 are each 40 mm,
Assuming 60 mm, the piston rod has P ₂ = 16P ₁
Is obtained, for example, if P ₁ = 7t, then P ₂
= 7 × 16 = 112 t, and even if the plunger 101 is driven with a relatively small force, a large operating force is obtained on the piston rod 103 that operates the machining unit.

[0005] However, while a large operating force can be obtained with the above-described pressure increasing means, the piston rod 103
Has a drawback that the stroke of the stroke is small. That is,
When the dimensions of the plunger 101 and the piston 102 are the above values, the plunger 101 is
m, the piston rod 103 has 200 × 1
Thus, only a stroke of /16=12.5 mm can be obtained.

In general, a working unit in a press working apparatus needs to insert and remove a work between a movable mold and a fixed mold, and the stroke of the movable mold operated by the piston rod 103 is as described above. For example, when it is small such as 12.5 mm, in the case of punching or drilling a flat work,
For example, when performing a deep drawing operation, there is a problem that a predetermined stroke cannot be performed because the movable stroke is insufficient.

On the other hand, if the stroke of the plunger 101 is further increased in order to increase the stroke of the movable type, not only will the size of the pressure increasing means be increased, but also the work tact will become longer. Not practical. In order to secure the stroke of the piston rod 103, it is conceivable to separately supply hydraulic oil into the hydraulic cylinder 100 above the piston 102. In this case, it is necessary to prepare a hydraulic unit including a hydraulic pump. In addition to the necessity, there is a problem that energy consumption increases.

The present invention solves the above-mentioned problems in the prior art, and provides a pressure increasing device capable of obtaining a large operating force on the output side while securing a relatively large stroke, and a press working device having the same. The task is to provide

[0009]

According to a first aspect of the present invention, a first cylinder and a second cylinder having a larger cross-sectional area than that of the first cylinder are provided. The first cylinder and the second cylinder are slidably interposed in the first cylinder and the second cylinder, respectively, while the first piston and the second cylinder are slidably interposed. The second piston is integrally provided with a protrusion having an axial length smaller than the stroke of the first piston, and this protrusion is slidably engaged with the first cylinder without a gap. The technical means of operating the piston to exert a larger operating force on the second piston via the liquid in the first cylinder and the second cylinder than that of the first piston is employed.

In the present invention, the outer ends of the first and second cylinders can be selectively communicable via a switching valve and a check valve.

In the above invention, the switching valve and the check valve can be interposed in parallel between the vicinity of the communicating portion of the second cylinder with the first cylinder and the liquid tank.

Next, in a second aspect of the present invention, the main body is formed by a substrate, a slider provided opposite to the substrate and formed so as to be movable in a direction perpendicular to the substrate, and driving means for driving the slider. A press working apparatus comprising: a pressure increasing device according to any one of the above inventions; and a processing unit comprising a movable mold and a fixed mold detachably provided between the substrate and the slider. The first part of the device
And the second piston are connected to the slider and the movable mold, respectively, and the processing unit is operated via the pressure intensifier by moving the slider toward the processing unit. .

Next, in the above invention, the substrate and the supporting plate can be formed so as to be movable in the vertical direction and the slider in the vertical direction.

In the above invention, the driving means can be constituted by a mechanism including a servomotor and a screw pair. In this case, the screw pair may be constituted by a ball screw.

In the above invention, the slider can be formed so as to slide along a guide bar provided between the substrate and the support plate.

[0016]

FIG. 1 is a front view of a main part showing an embodiment of the present invention. In FIG. 1, for example, guide bars 2 are erected at four corners of a substrate 1 formed in a rectangular shape, and a support plate 3 is fixed to an upper end of the guide bar 2 via an appropriate fastening means. Reference numeral 4 denotes a slider, which is interposed on the guide bar 2 so as to be slidable in the vertical direction. Reference numeral 5 denotes a nut member, which is integrally provided on the upper surface of the central portion of the slider 4 and screwed with a screw shaft 7 connected to a main shaft of a servo motor 6 provided on the upper surface of the support plate 3. In this case, the screw shaft 7 and the nut member 5 are preferably ball screws. The above constitutes the main body 8 of the press working device.

Next, reference numeral 9 denotes a processing unit, which comprises a pressure booster 10 constructed as described later, comprises a movable die 11 and a fixed die 12, and is provided detachably between the substrate 1 and the slider 4. Can be The processing unit 9 has a support plate 15 fixed to the upper end of a guide bar 14 erected at four corners of a substrate 13 formed in a rectangular shape, for example.
The structure is such that the pressure intensifier 10 is provided thereon.

The pressure increasing device 10 is driven by the vertical movement of the slider 4 as described later, and further operates the movable mold 11. The movable mold 11 may be configured to be constantly urged upward by, for example, a spring (not shown) or other means. The movable mold 11 and the fixed mold 12 are provided with, for example, a punch pad, a stripper, and a die (all not shown) in a detachable manner.

FIG. 2 is an enlarged vertical sectional view of a main part of the pressure increasing device 10 in FIG. 1, and the same parts are denoted by the same reference numerals as in FIG. In FIG. 2, reference numeral 20 denotes a hydraulic cylinder,
The first cylinder 21 and the second cylinder 22 having a larger cross-sectional area than that of the first cylinder 21 are integrally formed by directly communicating on the same axis. A first piston 23 and a second piston 24 are slidably interposed between the first cylinder 21 and the second cylinder 22, respectively.

Reference numeral 25 denotes a protrusion, and the second piston 24
And the length thereof in the axial direction is made smaller than the stroke of the first piston 23, and the protrusion 25 is slidably engaged with the first cylinder 21 without any gap. Reference numeral 26 denotes a bottom plate which is formed, for example, in the shape of a hollow disk, and is fixed to the support plate 15 at the bottom of the hydraulic cylinder 20 via bolts 27. The sliding portion of the hydraulic cylinder 20 with the first piston 23, the sliding portion of the first piston 23 and the protrusion 25 with the first cylinder 21, and the sliding portion of the second piston 24 with the second cylinder 22 And a sliding portion of the bottom plate 26 with the second piston 24 are provided with appropriate liquid sealing means such as a wear ring and an O-ring. Then, the first piston 23 is connected to the slider 4 shown in FIG. 1, while the second piston 24 is connected to the movable mold 11.

When the servo motor 6 shown in FIG. 1 is driven, the screw shaft 7 is rotated, the nut member 5 and the slider 4 are lowered, and the first piston 23 shown in FIG. 2 is lowered. , The first cylinder 21 and the second
The second piston 24 via the hydraulic oil in the cylinder 22
, A large working force is applied, and the predetermined processing is performed by the lowering of the movable mold 11. After the machining is completed, the nut member 5 and the slider 4 are raised by the reverse rotation of the servo motor 6, and the second piston is raised by the first piston 23 rising.
The piston 24 and the movable mold 11 rise and return to the original position.

FIGS. 3 to 7 are explanatory views showing the operating states of the pressure intensifier 10, and the same parts are denoted by the same reference numerals as in FIG. 3 to 7, reference numerals 31 and 32 denote a switching valve and a check valve, respectively, which are provided in series between the outer ends of the first cylinder 21 and the second cylinder 22.
A switching valve 34 and a check valve 35 are directly provided between the outer end of the second cylinder 22 and the oil tank 33, and a pressure adjusting valve 36 is provided in parallel with the switching valve 34 and the check valve 35. Is provided. Reference numeral 37 denotes a check valve, which is a first cylinder 2
1 is provided in series between the outer end portion and the oil tank 33.

Next, a switching valve 39 and a pressure regulating valve 40 which are connected in series, between the vicinity of the communication portion of the second cylinder 22 with the first cylinder 21 and the oil tank 38, And a check valve 41 disposed at the same time. 42
Is a check valve provided between the intermediate portion of the first cylinder 21 and the oil tank 38.

FIG. 3 shows that the first piston 23 and the second piston 24 are at the upper limit positions. From this state, the first piston 23 is moved from the servo motor 6, the screw shaft 7, the nut member 5 shown in FIG. It is lowered via the slider 4. In this case, the switching valves 31 and 39 are closed, and the switching valve 34 is closed.
Is open.

FIG. 4 shows a state where the first piston 23 and the second piston 24 are descending. That is, the first
As the pressure in the first cylinder 21 increases due to the lowering of the piston 23, the protrusion 25 that is engaged without any gap in the first cylinder 21 is pressed, and the upper end of the protrusion 25 The second piston 24 descends at substantially the same speed as the first piston 23 until it reaches the communication portion between the first cylinder 23 and the second cylinder 22.

In this case, hydraulic oil is supplied from the oil tank 33 to the first cylinder 21 above the first piston 23 via a check valve 37, while the second oil below the second piston 24 is supplied to the first cylinder 21. The hydraulic oil in the cylinder 22 is discharged into the oil tank 33 via the switching valve 34 and the check valve 35. Hydraulic oil is supplied from the oil tank 38 to the second cylinder 22 above the second piston 24 via a check valve 41.

FIG. 5 shows a state where the first piston 23 and the second piston 24 have reached the lowermost positions. That is, when the upper end of the protrusion 25 provided integrally with the upper part of the second piston 24 is separated downward from the communicating part between the first cylinder 21 and the second cylinder 22, the operation of the first piston 23 is started. Since the pressure on the oil acts on the entire upper end surface of the second piston 24, an actuation force corresponding to the ratio of the cross-sectional area of the two can be applied to the second piston 24, and as shown in FIG. Can be operated with a predetermined operating force. In this case, the second cylinder 2
The hydraulic oil in 2 is sealed in the second cylinder 22 by the action of the check valve 41 while the switching valve 39 is closed, and can be increased to a predetermined pressure by the first piston 23.

FIG. 6 shows a state where the first piston 23 and the second piston 24 have started to rise. That is,
The switching valves 31 and 39 are opened, and the switching valve 34 is closed. Then, the first piston 23 is raised by the reverse operation of the driving means.

FIG. 7 shows a state where the first piston 23 and the second piston 24 are rising. In this case, due to the rise of the first piston 23, the hydraulic oil in the first cylinder 21 above the first piston 23 is moved below the second piston 24 via the switching valve 31 and the check valve 32. It flows into the second cylinder 22. On the other hand, the hydraulic oil in the second cylinder 22 above the second piston 24 is discharged into the oil tank 38 via the switching valve 39 and the pressure regulating valve 40.

The hydraulic oil in the first cylinder 21 above the first piston 23 is supplied to the switching valve 31 and the check valve 32
, Flows into the second cylinder 22 below the second piston 24. Therefore, the second piston 24 also moves up with the rise of the first piston 23.

FIG. 8 shows a state where the first piston 23 and the second piston 24 have finished ascending and have returned to the upper limit positions. From the state shown in FIG.
Rises, and the protruding portion 25 provided integrally with the upper end thereof
However, after reaching the communication portion between the first cylinder 21 and the second cylinder 22, the second piston 24
Rise at substantially the same speed as the piston 23. Even after the second piston 24 has reached the upper limit position, the first piston
When the piston 23 further rises, the hydraulic oil above the first piston 23 is further discharged into the oil tank 33 via the pressure adjusting valve 36, and the hydraulic oil from the oil tank 38 into the first cylinder 21. Hydraulic oil is supplied via the check valve 42. Thereafter, the state shown in FIG. 3 is repeated.

In the above embodiment, an example of a hydraulic cylinder using hydraulic oil has been described, but water or another liquid may be used. In the embodiment of the invention described above, the so-called vertical type in which the substrate 1 and the support plate 3 are arranged in parallel with the horizontal plane and the guide bar 2 connecting them is provided in the vertical direction has been described. The present invention is also applicable to a so-called horizontal type in which 1 and the support plate 3 are provided in parallel with a vertical surface and the guide bar 2 is provided in a horizontal direction.

Next, the present invention is particularly effective for the case where the screw shaft 7 and the nut member 5 are in ball screw engagement, but is also applicable to the case where both are in normal screw engagement. is there. Of course, it is also possible to use a multi-thread or a multi-thread, including a ball screw engagement. The servo motor 6 for driving the screw shaft 7 is most commonly connected directly to the screw shaft 7 coaxially. However, the servo motor 6 is configured to transmit power via transmission means such as a gear and a timing belt. Is also good.

The screw shaft 7 is used for moving the slider 4.
Has been described, the screw shaft 7 may be fixed to the slider 4 and the nut member 5 screwed to the screw shaft 7 may be driven by the servo motor 6. Further, a crank mechanism may be used as a driving means of the slider 4.

Further, the guide bar 2 for guiding the movement of the slider 4 is preferably a plurality of guide bars for large ones or those requiring rigidity. However, one guide bar may be used. It may be formed in a beam shape, and the slider 4 slides or slides along the side surface.

Further, in addition to the single use of the press working apparatus of the present invention, a plurality of machines may be arranged in tandem to perform, for example, progressive feeding on a long workpiece. Applicable. The press working apparatus of the present invention can be used for assembling a plurality of parts, press-fitting, caulking, and the like, in addition to sheet metal working on a sheet material.

[0037]

According to the present invention, the configuration and operation as described above, the following effects can be obtained.

(1) The stroke of the movable mold required for the processing unit can be made relatively large. In particular, the range in which the operating force is small is moved at a relatively high speed, and the large stroke is obtained during the final relatively short stroke. Operating force can be obtained.

(2) For example, a very small amount of hydraulic oil is required for operating the apparatus, and it is not necessary to supply high-pressure hydraulic oil such as a hydraulic unit, so that energy consumption is extremely small.

[Brief description of the drawings]

FIG. 1 is a front view of a main part showing an embodiment of the present invention.

FIG. 2 is an enlarged longitudinal sectional view of a main part showing a pressure intensifier 10 in FIG.

FIG. 3 is an explanatory diagram showing an operation state of the pressure increasing device 10.

FIG. 4 is an explanatory diagram showing an operation state of the pressure increasing device 10.

FIG. 5 is an explanatory diagram showing an operation state of the pressure increasing device 10.

FIG. 6 is an explanatory diagram showing an operation state of the pressure increasing device 10.

FIG. 7 is an explanatory view showing an operation state of the pressure increasing device 10.

FIG. 8 is an explanatory diagram showing an operation state of the pressure increasing device 10.

FIG. 9 is a diagram illustrating an example of a pressure increasing unit that has been frequently used in the related art.

[Explanation of symbols]

 8 Body 9 Processing Unit 21 First Cylinder 22 Second Cylinder 23 First Piston 24 Second Piston 25 Projection

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3H086 BA03 BA14 BA19 BB07 BC11 BC12 4E090 AA01 AB01 BA02 CA03 CA07 HA01

Claims (8)

[Claims] A first cylinder and a second cylinder having a larger cross-sectional area than that of the first cylinder are integrally formed by directly communicating with each other on the same axis,
A first piston and a second piston are slidably interposed in the first cylinder and the second cylinder, respectively, and the second piston has an axial length smaller than a stroke of the first piston. And a projection having an integral length, and the projection is slidably engaged with the first cylinder without a gap, and the liquid in the first cylinder and the second cylinder is actuated by the operation of the first piston. And a second piston having a greater operating force than that of the first piston. 2. The pressure booster according to claim 1, wherein the first cylinder and the second cylinder are selectively communicable between outer ends of the second cylinder via a switching valve and a check valve. apparatus. 3. A switching valve and a check valve are interposed in parallel between a vicinity of a communication portion of the second cylinder with the first cylinder and the liquid tank. The pressure intensifier according to claim 1. 4. A main body comprising a substrate, a slider provided to face the substrate and formed to be movable in a direction perpendicular to the substrate, and driving means for driving the slider. A press working device comprising a pressure increasing device according to any one of claims 1 to 3 provided between a slider and a processing unit including a movable type and a fixed type, which is detachably provided. The first piston and the second piston are connected to the slider and the movable mold, respectively, and the processing unit is operated via the pressure increasing device by moving the slider toward the processing unit. Press working equipment. 5. The press working apparatus according to claim 4, wherein the substrate and the support plate are formed so as to be parallel to a horizontal plane and the slider is movable in a vertical direction. 6. The press working apparatus according to claim 4, wherein the driving means is constituted by a mechanism including a servomotor and a screw pair. 7. The press working apparatus according to claim 6, wherein the screw pair is formed by a ball screw. 8. The press working apparatus according to claim 4, wherein the slider is formed to slide along a guide bar provided between the substrate and the support plate.