JP3161637B2 - Press brake - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ram parallelism adjusting device.
The provided, and to easily adjust the parallelism of the ram-flop
For less brakes .

[0002]

2. Description of the Related Art Conventionally, a press brake for bending a plate-shaped work between an upper die mounted on a vertically movable ram and a lower die fixed on a table performs high-precision bending. Therefore, the ram reaching the bottom dead center needs to be parallel to the bed. However, even if the parallelism of the ram is accurately maintained, there may be variations in the thickness of the workpiece to be bent, or variations in the tensile strength of the workpiece may prevent accurate bending. For this reason, conventionally, an oil paper or shim is put under the lower mold and adjusted to improve the bending accuracy.

[0003]

However , in this method, it takes a long time to perform adjustment, the work efficiency is poor, and the adjustment amount is not quantified, so that adjustment requires skill. The present invention has been made in order to improve the above-described problem, and provides a press brake capable of performing high-precision bending processing by adjusting the parallelism of a ram, even if there is a variation in a work thickness or tensile strength. The purpose is to do so.

[0004]

SUMMARY OF THE INVENTION The present invention in order to achieve the above object, the invention according to claim 1, by a hydraulic cylinder 2 provided on the left and right of the ram 3 by vertically moving the ram 3, the ram 3 Upper mold 4 and table 1a attached to the lower part of
With bending a workpiece 6 between the fixed lower mold 5 above, by switching the hydraulic pressure switchover valve 9 by the presser 19, 22 provided in the ram 3, a preset lower dead ram 3 in a press brake so as to stop at a point location, opposite to the pushing element 19, 22 at least one of the pressure members 19 and 22, across the ram 3
Ram parallelism adjustment mechanism 23 that can be adjusted from the ram surface side
The position of the bottom dead center of the ram 3 can be adjusted by
It is a s brake . In order to achieve the above objective,
The invention according to claim 2 is pivotally attached to the ram 3 so as to be swingable,
When the ram 3 descends, the hydraulic pressure switching valve 9 is pushed upward.
A swing lever 20 having pressers 19 and 22 for pressing is provided.
Through the ram 3 at the lower side of the swing lever 20
Adjustable from the ram surface side opposite to the pressers 19 and 22
Press brake equipped with an effective ram parallelism adjustment mechanism 23
is there.

[0005]

[Operation] With the above configuration, even if there is a variation in the plate thickness of the work, by adjusting the parallelism, it is possible to perform a bending process with high accuracy without variation in the left and right bending angles.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described in detail with reference to the drawings. In the figure, 1 is a main body of a press brake, and a pair of hydraulic cylinders 2 are provided on both upper sides, and a ram 3 is driven up and down by these hydraulic cylinders 2. An upper die 4 is attached to a lower portion of the ram 3, and the upper die 4 and a lower die 5 fixed on the table 1a.
The plate-like work 6 can be bent between the two.

The press brake body 1 has a ram 3
The supporting members 8 are fixed to both sides of the supporting member 8, and the hydraulic switching valves 9 are attached to the supporting members 8, respectively. Together with the respective hydraulic pressure switchover valve 9 is in contact with one end of the pivoted lever 11 by a pin 10 to the lower portion of the support member 8 so that the tip of the spool 9d protruding downward is shown in FIG. 3, other end of the lever 11 is in contact with the lower end of the push rod 13 which is supported on the support member 8.

[0008] The push rod 13 is not formed to be hollow, the lower end portion of the screw shaft 14 is inserted into the upper end. With the above screw shaft 14 is screwed in the center of the worm wheel 15 rotatably mounted within the upper portion of the push rod 13, the above-mentioned worm wheel 15 provided at both ends of the synchronization shaft 16 worm The left and right screw shafts 14 can be simultaneously adjusted up and down by rotating the synchronous shaft 16 with a handle (not shown).

On one side of the upper part of the ram 3, a pressing element 1
A swing lever 20 substantially L-shaped opposite to that of the swing lever 9 is provided.
The presser 19 is located above one screw shaft 14,
When the ram 3 reaches the bottom dead center, the push rod 13 is pressed downward via the screw shaft 14. The rocking lever 20 of the inverted L-shaped and is pivoted rotatably to the ram 3 by the bent portion pin 21, thereby vertically moving together with the ram 3, 3 on the upper end of the rocking lever 20 as shown, the pushing member 22 for pushing the push rod 13 downwards via the screw shaft 14 downward when the other of the ram 3 is provided, on the lower end side of the ram parallelism adjusting mechanism 23
One end portion of the adjusting screw 23a provided is attached. The other end of the adjusting screw 23a passes through the ram 3,
It is screwed to an adjusting member 23b fixed to the ram surface on the opposite side of the swinging lever 20, and by rotating the adjusting screw 23a, the swinging lever 20 can swing around the pin 21. I have.

A compression spring 23c urges the swing lever 20 in a direction away from the adjustment member 23b .
23d is a set screw for fixing the adjustment screw 23a at the adjustment position. On the other hand, FIG. 5 shows a hydraulic circuit for supplying a hydraulic pressure to each hydraulic cylinder 2. The hydraulic pressure discharged from a hydraulic pump 25 is supplied to each hydraulic cylinder 2 via a hydraulic switching valve 9.

[0011] Next In operation, when switched to the lowered position 9a the hydraulic pressure switchover valve 9 so as to bending the workpiece 6, the discharge pressure of the hydraulic pump 25 to the upper chamber 2 ₁ of the hydraulic cylinder 2 from the hydraulic pressure switchover valve 9 The ram 3 is lowered by the left and right hydraulic cylinders 2. Then, at the same time when the upper die attached to the ram 3 comes into contact with the upper surface of the work 6, the bending of the work 6 is started between the lower dies fixed on the table 1 a, and the ram 3 is set to the predetermined lower die When the point is reached, the pressing element 19 provided on the ram 3
And the presser 22 provided on the swing lever 20 is the screw shaft 1
The push rod 13 is pushed down via 4. As a result, the lever 11 is rotated by each push rod 13 and the hydraulic pressure switching valve 9 is switched from the lower position 9a to the neutral position 9b, so that the ram 3 is stopped at the preset bottom dead center and the workpiece 6 is bent. Complete. When subsequently the hydraulic pressure switchover valve 9 is switched to the raised position 9c, since the oil pressure is supplied to the lower chamber 2 ₂ of the hydraulic cylinder 2, the ram 3 is elevated to its original position.

The above is the case where the ram 3 descends while maintaining the parallelism to bend and lower the work 6. However, an error occurs in the bending angle between the ram left and right due to variations in the thickness of the work 6 and the tensile strength. In this case, the ram parallelism adjusting mechanism 23
Of the swing lever 20 by rotating the adjusting screw 23a of the
The pusher 22 of the swing lever 20 is turned around
Adjust the timing to hit the top of 4.

That is , by intentionally changing the bottom dead center stop position of the ram 3 to adjust the right and left bending angles to match, the adjustment amount is indicated by a scale (not shown) displayed on the adjustment member 23b. Can be confirmed as a numerical value. After the right and left parallelism of the ram 3 is adjusted as described above, the bending process is performed in the same manner as described above, so that the bending process can be performed with high accuracy without errors in the left and right bending angles. Further , by previously adjusting the bottom dead center stop position of the ram 3 so as to be different between the left and right, it is possible to perform a bending process such as a cone bending or an eccentric bending for forming a tapered cylinder. In the above embodiment, the ram parallelism adjusting mechanism 2 is used.
Although the adjustment screw 23a of No. 3 is manually adjusted in rotation, it may be automatically adjusted by using a motor or the like. Alternatively , the swing lever 20 may be stopped and the ram parallelism adjustment mechanism 23 directly controls the rotation. The position of the pressing element 22 may be adjusted.

[0014]

According to the present invention, as described in detail above, since the parallelism at the bottom dead center of the ram can be arbitrarily adjusted, even if the thickness and tensile strength of the work vary, By adjusting the parallelism, it is possible to perform high-precision bending without error in the left and right bending angles. Also ,
Because the amount of adjustment can be quantified, it is possible to adjust without requiring any skill, and by changing the position of the bottom dead center of the ram in advance, processing such as cone bending and eccentric bending can be easily performed. become.

[Brief description of the drawings]

FIG. 1 is a plan view of a press brake according to an embodiment of the present invention.

FIG. 2 is a front view of a press brake according to one embodiment of the present invention.

FIG. 3 is a side view of a press brake according to one embodiment of the present invention.

FIG. 4 is an enlarged sectional view taken along line AA of FIG. 2;

FIG. 5 is a hydraulic circuit diagram of a press brake according to one embodiment of the present invention.

[Explanation of symbols]

1a: table, 2 ... hydraulic cylinder, 3 ... ram, 4 ... upper mold, 5 ... lower mold, 6 ... work, 19, 22 ... presser, 23
… Ram parallelism adjustment mechanism.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B21D 5/02

Claims (2)

(57) [Claims] 1. A ram 3 is moved up and down by hydraulic cylinders 2 provided on the left and right sides of the ram 3 to move between an upper mold 4 attached to a lower portion of the ram 3 and a lower mold 5 fixed on a table 1a. In a press brake in which the work 6 is bent and the hydraulic pressure switching valve 9 is switched by the pressers 19 and 22 provided on the ram 3 to stop the ram 3 at a preset bottom dead center position. , At least one of the pressing elements 19 and 22 is
Adjustable from the ram surface side opposite to the indenters 19 and 22
Bottom dead center position of ram 3 by the adjusted ram parallelism adjustment mechanism 23
Press brake characterized in that it is possible to adjust the
Ki . (2) It is pivotably attached to the ram 3 and its upper part
Presses the hydraulic switching valve 9 when the ram 3 is lowered.
A swing lever 20 having indenters 19 and 22 is provided.
The ram 3 is penetrated to the lower side of the swing lever 20 and
Ram that can be adjusted from the ram surface side opposite to 19 and 22
The press blur according to claim 1, further comprising a parallelism adjusting mechanism (23).
Brakes.