JPH046479B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hydraulic press that makes it easy to adjust the ram stroke, and in particular allows synchronization of the ram stroke even when two or more presses are connected. This article relates to a multi-unit hydraulic press.

[Conventional technology] When processing a workpiece with a hydraulic press such as a press brake or folding machine, bending of the ram and deflection of the frame and bed occur. It is difficult to bend the parts accurately. Therefore, the applicant has previously
In No. 1311984 (Special Publication No. 59-10880), a pair of left and right stroke adjustment control valves is installed on a bracket fixed to the frame at a position that is not affected by elongation during press work or on a garter fixed between the frames. We have invented a device that enables servo-type ram adjustment by attaching an operating rod to the side that can press down the valve shaft of these control valves, and moving the operating rod up and down using a motor drive.

[Problems to be Solved by the Invention] In the above patent, the left and right operating rods press the top of the spool valve, so the workpiece cannot be folded accurately at a position offset from the center of the machine, that is, under an eccentric load. In order to bend it, each stroke adjustment member needed to be made of highly accurate parts. Also,
With conventional press brakes, the bending length is determined by the distance between the frames, so it is commonly used to bend workpieces up to a maximum of about 6m, but it is possible to bend long objects over 6m in one process. Nothing is known that will complete it.

An object of the present invention is to provide a hydraulic press that allows accurate ram stroke adjustment with simple members. Another object of the present invention is to provide a multiple hydraulic press that can bend short and small workpieces in the same way as usual, and can also bend objects of 6 m or more with the same precision.

[Means for Solving the Problems] In order to achieve the above object, the first aspect of the present invention is to provide a control valve for lower limit stroke adjustment and left/right synchronization corresponding to each hydraulic cylinder in the approach circuit of the left and right hydraulic cylinders. The hydraulic press is equipped with an operating member, which is the operating part of both control valves, and is connected by a rotatable horizontal shaft to move the ram in parallel; In addition to installing the valve, an operating member having a threaded rod screwed onto the upper part of the rod is inserted into the valve body; a pressing member is provided on the back of the ram to abut the upper end of the threaded rod near the lower stroke limit; Furthermore, the hydraulic press is equipped with means near the control valve for changing the effective length of the operating member by raising and lowering the threaded rod relative to the rod by rotation of the horizontal shaft.

Further, the second invention is such that a second and subsequent hydraulic presses are arranged in series or detachably on the extension line of the processing line of the hydraulic press based on the above invention, and at least one end of the horizontal axis of each hydraulic press is A connecting shaft is provided that interlocks with the horizontal shaft, and a coupling with a clutch is provided at the other end of the connecting shaft to connect the respective horizontal shafts when two or more hydraulic presses are moved and connected in series. It is characterized by having been established.

[Operation] After the ram moves from high-speed descent to low-speed descent,
The pressing member on the ram side hits the screw rod provided on the fixed part side, actuating the control valve and machining the workpiece with a predetermined pressing force. At this time, if the workpiece is placed at a position offset from the center of the machine and the ram is lowered, the ram will tilt to the left or right due to the eccentric load near the lower stroke limit. Due to this inclination, the control valve corresponding to the threaded rod that precedes is closed to stop the downward movement, and by opening the other control valve, the inclination is corrected and the ram is moved in parallel.

Since the present invention has the above functions as a single hydraulic press, when the second and subsequent hydraulic presses are arranged side by side on the extension line of the processing line of the first hydraulic press, the connection derived from the horizontal axis for adjustment By connecting the shafts with a coupling with a crack, it is possible to change the bending length and process long workpieces. For example, when a press brake is used as a hydraulic press, two or more machines with different or equivalent machining lengths are arranged so that they can be connected or moved in and out, and usually they are folded at intervals using separate press brakes. When performing bending and the length of the workpiece is large, two or more press brakes are connected and the connecting shaft ends of each press brake are connected with a coupling with a clutch, and the servo strokes of each press brake are synchronized. Accurately perform bending over the entire length.

[Example] In the following example, a case will be explained in which a press brake is used as a hydraulic press.

Figure 1 is a front view of the press brake of the present invention, Figure 2 is a front view of the press brake of the present invention;
The figure is an enlarged front view with main parts cut away. However, for ease of understanding in both figures, the parts located behind the ram are shown with solid lines.

In the figure, 10 is a press brake installed on the floor, 1
1 is a left and right frame, 12 is a bed, 13 is a ram, 14 is a main cylinder for raising and lowering the ram attached to the front end of the frame, 15 is a piston rod, and 16 is a rotatable cylinder that is horizontally suspended on the fixed part side of the back of the ram 13. 17 is a connecting shaft interlocked with the horizontal shaft 16; 18 is a coupling with a clutch attached to one end of the connecting shaft 17; 19 is a hydraulic pressure generating device; These are a pair of control valves for lower limit stroke adjustment and left/right synchronization that are installed on the side of a fixed part such as a frame or portal bracket.

As shown in FIG. 1, pressure oil from the hydraulic pressure generating device 19 is supplied to the main cylinder 14 through the approach circuit 21, the control valve inlet port 23, the valve chamber 24, and the outlet port 25, and processes the ram 13. . At this time, the oil on the back side of the cylinder 14 returns to the oil tank in the hydraulic pressure generator through the return circuit 22. When the oil passage in the hydraulic pressure generating device 19 is switched, pressure oil is supplied in the opposite direction, causing the ram to rise and return to its original state.

As shown in FIG. 2, the control valve 20 is provided with an actuating member 26 formed by protruding the upper half of a threaded rod 28 from the upper part of the rod 27. Actuation member 26
The lower part of the control valve 20 is inserted into the valve chamber 24 of the control valve 20 to form a valve body, but as shown in FIG. Actuating member 2 via supported lever 31
It is also possible to use a type that transmits the movement of 6 to the valve body 29.

On the other hand, a bracket 34 is provided on the back side of the ram 13, and a pressing member 35 is provided which comes into contact with the upper end of the threaded rod 28 near the lower stroke limit and leaves when the ram rises.
Install. Furthermore, at the top of the control valve 20,
Around the operating member 26, a means 40 is attached to the rod 27 for raising and lowering the threaded rod 28 to change the effective length of the operating member 26.

As shown in FIG. 2, the changing means 40 includes a horizontal shaft 16 rotatably mounted horizontally on the fixed part side behind the ram, and a horizontal shaft rotation drive device 36 consisting of an NC motor 37 and a transmission member 38. , the bevel pinion 4 is supported by a bevel pinion 41 fixed to the end of the horizontal shaft 16 and a bracket 39 provided on the fixed part side.
1, a rod 27 that is inserted into the bevel gear 42 via a sliding key 44 so as to be able to rise and fall freely, and a rod 27 that is constantly suspended.
A coil spring 46 is compressed between the upper surface of the bevel gear 42 and the collar 45 at the upper end of the rod, and a threaded rod 28 is screwed into the rod 27 so that it can be moved up and down relative to the rod 27 while being guided by a detent key 47 as the bevel gear 42 rotates. It is made up of.

When the NC motor 37 is rotated and the bevel gear 42 is rotated via the transmission member 38, the horizontal shaft 16, and the pinion 41, the rod 27, which is guided using a sliding key, rotates. In addition, the screw rod 28, which is prevented from rotating by the key 47, is raised or processed to change the effective length (height) of the actuating member 27. This effective length determines the servo stroke distance from low speed operation to stop in the machining stroke of the ram 13.

In order to perform manual operation instead of automatic operation using the NC motor 37, a manual handle may be provided at the other end of the horizontal shaft 16, or a transmission member 4 as shown in FIG.
An operating shaft 50 related to the horizontal axis is provided via 8 and 49, and a manual handle 51 is attached to the end of the operating shaft 50. Note that the part surrounded by the chain line 33 in FIG.
indicates that it is attached to the fixed part of the machine.

Furthermore, a coupling 18 with a clutch is provided in order to synchronize the servo stroke when the press brake 10 is connected. In the case of FIG. 2, this coupling ring 18 is provided at one end of a connecting shaft 17 that is horizontally suspended parallel to the horizontal shaft 16 and is transmitted using gears 52 and 53, but in the case of FIG. As shown, a connecting shaft 54 may be provided at a position symmetrical to the horizontal axis on the extended axis of the horizontal shaft 16, a bevel gear 55 that meshes with the bevel gear 42 may be fixed to one end of the connecting shaft 54, and a coupling 18 with a clutch may be attached to the other end. .

Next, the effect will be explained.

To fold a worksheet using a press brake as shown in Figures 1 and 2,
After placing the worksheet on top of the lower die and determining the bending length, drive the main cylinders 14 and 14 to rapidly lower the ram 13, and at the set position, limit switch LS ₁ is turned on and low-speed operation begins. move (8th
(see figure). After low speed operation, press member 3 on the ram side
5 hits the upper end of the actuating member 26, that is, the upper end of the screw rod 28, the control valve 20 is turned on, the valve seat is throttled, and the speed is further reduced, and the lower limit switch LS ₂ detects the lower limit and stops the operation.
During this time, the conversion means 40 is driven by the rotation of the horizontal shaft 16, and the threaded rod 28 is lowered to gradually release the actuating member 26.
Decrease the effective length of In other words, the screw rod is rotated in relief. After gradually maintaining the maximum pressure, the oil passage is switched to raise the ram 13, and then the horizontal shaft 16 is operated to return the threaded rod 28 to its original height.

The above operation will be explained in more detail. Figure 3A,
Figure 3B shows the position of actuating member 2 in Figure 8, that is, when the ram descends at high speed and touches LS ₁ .
6 and the relative position of the control valve 20 and the upper die 63
Indicates the location of In this state, the pressing member 3 on the ram side
5 and the threaded rod 28, and the distance l between the rod 27 of the actuating member 26 and the valve seat, the upper surface of the worksheet 60 placed on the lower mold 62 and the tip of the upper mold 63 are Only the distance L+l has been completed.

Next, when the ram is moved to the position shown in FIG. 8 due to low speed operation, it is lowered by L+l as shown in FIGS. 4A and 4B, and the tip of the lower mold comes into contact with the worksheet. From this point on, while performing relief rotation of the threaded rod as described above, that is, while rotating the bevel gear 42 and lowering the threaded rod 28 to shorten the effective length of the actuating member 26, the ram is moved a distance W (Figs. 5A and 5B). (Fig.) and stop at the position shown in Fig. 8.

For example, if the ram's descending speed is 8 in the release rotation,
mm/sec, if the threaded rod 28 is raised at a rate of 5 mm/sec, the pressing member 35 and the threaded rod 28 can be held without separating until the final point, and maximum bending pressure can be applied.

When the ram 13 is lowered with an inclination on either the left or right side due to an eccentric load, the control valve on the preceding side has a smaller opening than the other, so the main cylinder on the inclination side is stopped. During this time, a large pressure is supplied to the other main cylinder to restore the tilt and to effect translation of the ram.

The above press brake can be used alone, but a second or more hydraulic presses can be connected or movably moved laterally on the extension line of the first hydraulic press to increase the length. Prepare for bending the workpiece. In the embodiment shown in FIG. 9, the first press brake 10 is fixed and the second press brake 7 is fixed.
0 is provided with wheels 71 and arranged so as to be movable laterally.

Normally, the two machines are separated and operated separately as shown in Figure 9, and when the workpiece length is large, the wheels 71 are driven by the moving drive mechanism 72 and the rails 73 are driven.
Move and connect them as shown in Figure 10. After connecting, couple the coupling rings 18 of both machines,
The horizontal axes 16 are mutually synchronized and the rams are synchronized to accurately process the entire length of the workpiece. If there is a gap in height when the two machines are brought close together, the lower die is lifted to level them. The press brakes are not limited to the same one, but those with different capabilities may be arranged side by side, and the number of press brakes is not limited to two, but three or more may be connected.

[Effects of the Invention] As described above, according to the present invention, the effective length of the actuating member is controlled by the control valves installed corresponding to the left and right hydraulic cylinders by rotating the threaded rod with relief near the lower limit stroke of the ram. So,
The servo stroke of the ram can be easily performed. In addition, when the workpiece length is large, two machines,
Or by connecting more hydraulic presses and coupling the horizontal shafts for stroke adjustment,
It is possible to accurately bend long workpieces.

[Brief explanation of drawings]

Fig. 1 is a front view of the hydraulic press of the present invention, Fig. 2 is a partially cutaway enlarged front view of main parts, and Figs. 3A to 5.
Figure A is a sectional view showing the relationship between the ram stroke and the control valve, Figures 3B to 5B are side views showing the relationship between the ram stroke and the upper die, and Figure 6 is a modification of the mounting position of the coupling with clutch. Fig. 7 is a side view when a lever is interposed between the actuating member and the control valve, Fig. 8 is a ram stroke diagram, and Figs. 9 and 10 are diagrams showing the hydraulic press. It is a front view when it is set as a continuous type. 10,70...Hydraulic press (press brake),
11...Frame, 12...Bed, 13...Ram, 14...Main cylinder, 16...Horizontal axis, 17...
...Operating shaft, 18...Coupling, 20...Control valve, 26...Operating member, 27...Rod, 2
8... Screw rod, 35... Pressing member, 36... Rotation drive device, 37... NC motor, 40... Conversion means, 41... Pinion, 42... Bevel gear, 4
4... Sliding key, 47... Detent, 46... Coil spring, 51... Handle, 72... Movement drive mechanism.

Claims (1)

[Scope of Claims] 1. Control valves for lower limit stroke adjustment and left and right synchronization corresponding to each hydraulic cylinder are provided in the approach circuits of the left and right hydraulic cylinders, and the operating members that are the operating parts of both control valves are rotatably provided. It is a hydraulic press that is connected by a horizontal axis to move the ram in parallel, and a) the control valve is installed on the fixed part side behind the ram, and a threaded rod is installed in the upper part of the rod in the valve body. a screwed operating member is inserted, b. a pressing member is provided on the back of the ram that comes into contact with the upper end of the threaded rod near the lower limit of the stroke, c. A hydraulic press characterized in that a means is attached for changing the effective length of an operating member by raising and lowering a screw rod relative to the rod. 2. The means for changing the effective length of the operating member includes a horizontal shaft rotatably mounted horizontally on the fixed part side behind the ram, a rotation drive device for the horizontal shaft, and a bevel pinion fixed to the end of the horizontal shaft. A pair of bevel gears are placed at intervals on the left and right behind the ram, a rod is inserted into each bevel gear via a sliding key, a coil spring gives the rod a tendency to constantly lift it, and the rod is raised and lowered by the rotation of the bevel gear. The hydraulic press according to claim 1, comprising a threaded rod screwed into the upper part. 3. The hydraulic press according to claim 2, wherein the rotational drive device for the horizontal axis is an NC motor. 4 A second hydraulic press is placed on the extension line of the first hydraulic press.
The following hydraulic presses are multiple hydraulic presses in which a plurality of hydraulic presses are arranged so that they can be connected or moved in and out, and each hydraulic press constituting the multiple hydraulic press has: a. Each hydraulic press in the approach circuit of the left and right hydraulic cylinders In addition to providing a control valve for lower limit stroke adjustment and left/right synchronization corresponding to the hydraulic cylinder, the operating members that are the operating parts of both control valves are connected by a freely rotatable horizontal shaft. At the same time, an operating member with a threaded rod screwed onto the upper part of the rod is inserted into the valve body, and the screws of each control valve are installed on the back of the ram near the lower stroke limit. A pressing member is provided that comes into contact with the upper end of the rod; d. A means is installed at the upper part of both control valves to raise and lower the threaded rod with respect to the rod by rotation of the horizontal shaft to change the effective length of the operating member; e. At least one of the shafts is provided with a connecting shaft, and the other end of the connecting shaft is provided with a connecting shaft that connects and connects the horizontal shafts of each hydraulic press when two or more adjacent hydraulic presses are moved and connected. A hydraulic press characterized by being equipped with a coupling with a clutch that enables synchronous operation of ram lower limit control of the hydraulic press. 5. The means for changing the effective length of the operating member includes a horizontal shaft rotatably mounted horizontally on the fixed part side behind the ram, a rotation device for the horizontal shaft, and a bevel pinion fixed to the end of the horizontal shaft. A pair of bevel gears are placed at intervals on the left and right behind the ram, a rod is inserted into each bevel gear via a sliding key, a coil spring gives the rod a tendency to constantly lift it, and the rod is raised and lowered by the rotation of the bevel gear. The hydraulic press according to claim 4, comprising a threaded rod screwed into the upper part. 6. The hydraulic press according to claim 5, wherein the rotational drive device for the horizontal axis is an NC motor.