JP2558928Y2 - Press brake - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION This invention relates to a press brake.

[0002]

2. Description of the Related Art Conventionally, in a press brake of a type in which a pressurizing cylinder is provided near both ends of a movable table, resistance to bending processing such as characteristics of a material to be processed, such as a tensile strength, an elastic limit, a yield point, an elastic coefficient, etc. The bending force appears as a drag, and the central portion of the ram tends to warp and the central portion of the fixed table warps downward during bending.

[0003]

However, in the bending process in the prior art press brake, the upper and lower tables are bent by the bending reaction force from the work, and the bent work is usually called a center sag. It has a shape that makes the part sweet.

[0004] Therefore, in order to solve the above-mentioned problem, an apparatus for correcting center sagging using wedges has been used.
That is, the table is curved by adjusting the wedges attached to the upper table or the lower table, but the bending of the upper and lower tables differs depending on the bending length and the pressing conditions. Must be done. Also, by attaching a drive device, there is a device that assumes a bending of the table under bending conditions and curves the table, but the mechanism becomes complicated,
The cost is high.

A device is also used in which pins are mounted near the center of an upper table or a lower table and the pins are supported by two front and rear plates so that the upper and lower tables have the same deflection. Since the position of the supporting pin is fixed, there has been a problem that the bending of the upper and lower tables is not the same due to the difference in bending length.

[0006] This invention eliminates the need for expensive correction devices,
It is an object of the present invention to provide a press brake in which the bending of a movable table corresponding to the bending length of a work and the bending of a fixed table are made equal to simplify the mechanism and reduce the cost.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention provides an upper table at the upper part of the left and right side plates, a lower table at the lower part, and an appropriate one of the upper table and the lower table. Is a movable table that can move up and down, and the other table is fixed to the side plate as a fixed table.In the press brake, the fixed table is provided with slits that are opened on both left and right sides in a symmetrical manner. A frame capable of adjusting the warpage of the fixed table at the time of bending the work is provided so as to be position-adjustable.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

Referring to FIGS. 1 and 2, the press brake 1 includes an upper table 3, which is mounted on the upper side of the side plates 5, 5 and has piston rods 9, 9 of hydraulic cylinders 7, 7. It is a movable table connected with.
A punch P is provided below the upper table 3.

A lower table 1 is provided below the side plates 5 and 5.
1 is provided. A die D is provided above the lower table 11.

With the above configuration, when the hydraulic cylinder 7 is operated, the upper table 3 is moved up and down via the piston rod 9. Therefore, the work placed on the lower table 11 is bent by the cooperation of the punch P and the die D.

The lower table 11 is held on the side plates 5 and 5 by a holding device 13 using a fixture such as a bolt penetrating a long hole.

The moving members 15A and 15B shown generally include:
This is a parallelism maintaining mechanism that acts so that the lower table 11 bends following the warp of the upper table 3 when bending the work.

Referring to FIG. 1, a lower table 11 as a fixed table is formed with slits 17A and 17B which are opened on both left and right sides and which are inclined downward at an appropriate length, and which are formed symmetrically. , 17B with moving member 1
5A and 15B are movably fitted.

FIGS. 3 and 4 show moving members 15A and 15B.
FIG. 5 shows another embodiment. In each case, the operation is performed manually. Moving members 15A and 15B
Are the same members, so one of the moving members 15A will be described.

3 and 4, FIG. 3 is a front view of the moving member 15A, and FIG. 4 is a side view of FIG. A slight clearance 19 is made in the slit 17A opened in the lower table 11, and the top 21 is fitted so as to be position-adjustable. The cross section of the slit 17A and the cross section of the top 21 have similar similar shapes.

The top 21 is moved by a moving plate 25 by a support shaft 23.
, And is attached to a stop rod 27. The stop rod 25 is grasped by hand, moved to a predetermined position of the top 21 by a structural analysis and a bending test, and the stop rod 27 is tilted sideways (FIG. 3), the clearance 19 is closed by the side pressure of the top 21 and the top 21 is stopped.

The predetermined position of the frame 21 is shown in FIG.
As shown in FIG.
A pointers 31A and 3 attached to the side of A and provided on the movable plate 25
Determined by 1B.

FIG. 5 shows another embodiment of the moving member 15A. In this embodiment, the description of the same members as those in the first embodiment is omitted.

The top 21 is provided through the movable plate 25 by a stud bolt 33 with a round head. The round head of the stud bolt 33 is picked up by hand and moved to a predetermined position of the top 21, The movable plate 25 is fixed by bolts with a fixing tool 35.

FIGS. 6 and 7 show a third embodiment of the moving member, which is automatically operated. In this figure, two moving members 15A and 15B are provided on the lower table 11 symmetrically with respect to the left and right via a central portion AA (FIG. 6). Since the moving members 15A and 15B are the same member, one of the moving members 15A will be described.
In this embodiment, the gear device 37 is used as a drive source. The gear device 37 includes a driving gear 43 fixed to a motor shaft 41 of a motor 39 mounted on the lower table 11.
It meshes with a driven gear 47 attached to the tip of the ball screw 45, and transmits the drive of the motor 39 to the ball screw 45.

A male screw is engraved on the ball screw 45, and a nut member 51 is fixed to the back surface of a moving plate 49 attached to the upper surface of the top 21 of the moving member 15A. The female screw and the male screw cut in the ball screw 45 are engaged with each other, and the top 21 moves along the LM guide 53 by the engagement rotation.

8 and 9, FIG. 8 shows a case where a long work W is bent, and FIG. 9 shows a case where a short work W is bent.

In the case of a long work, since the bending length is long, the degree of curvature is deep, and the moving members 15A and 15B provided on the lower table 11 must be strongly pressed (deeply into the slits 17A and 17B). In the case of bending a short work, the action of the moving member can be reduced because the bending length is short.

In the above configuration, the pressurized oil is supplied to the hydraulic cylinders 7 and 7, the upper table 3 is lowered, and the die D mounted on the lower table 11 and the upper table 3
The bending process is performed by the punch P mounted on the dies.

During bending of the workpiece, as is generally known, the upper table 3 tends to warp upward, the lower table 11 tends to warp downward, and the central portions are separated from each other. In this embodiment, since the lower table 11 has the slits 17A and 17B, the left and right ends of the lower table 11 are free ends and are curved downward. The curvature of the lower table 11 is adjusted by manually or automatically moving the pieces 21 of the moving members 15A and 15B provided on the lower table 11 to adjust the distance from both ends. Can be made almost parallel by following the curve of

By the action of the parallelism holding mechanism, the lower table 11 follows the upward warpage of the upper table 3 (the XX line shown by the imaginary line) and warps upward during the bending process (the imaginary line). X′-X ′ line)
The gap between the upper table 3 and the lower table 11 is kept substantially equal over the entire length, so that the above-described conventional problem is solved.

In the above description, the structure in which the upper table 3 is provided so as to be vertically movable and the lower table 11 is fixedly provided has been described. However, the present invention is not limited to the above embodiment. May be provided movably up and down, and the upper table 3 may be fixedly provided.

Further, the parallelism maintaining mechanism may be provided on the upper table 3, and furthermore, the automatic moving member 15A or 1A may be provided.
A motor 35 may be provided for each of 5B.

[0030]

As will be understood from the above description of the embodiments, the present invention basically comprises an upper table (3) at the upper part of the left and right side plates (5, 5) and a lower table (1) at the lower part.
1), a press brake in which one of the upper table (3) and the lower table (11) is a movable table capable of moving up and down and the other table is a fixed table fixed to the side plates (5, 5). In the fixed table, slits (17A, 1
7B) are provided symmetrically, and the left and right slits (17
A, 17B) is provided with a top (21) capable of adjusting the warpage of the fixed table at the time of bending the work (W) so as to be position-adjustable.

As is apparent from the above configuration, in the present invention, the fixed table of the press brake is provided with slits opened on both right and left sides in a symmetrical manner.
In the left and right slits, there are provided tops capable of adjusting the warpage of the fixed table at the time of bending the work so as to adjust the position.

Therefore, the left and right ends of the fixed table are free ends due to the presence of the left and right slits, and are likely to bend when the work is bent. And, by adjusting the position of the top along the slit,
The distance from the left and right ends of the fixed table to the top is different, and the warping state near the left and right ends of the fixed table changes.

That is, according to the present invention, the fixed table can be easily driven to warp in accordance with the warp of the movable table at the time of bending the work with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a front view of one embodiment of a press brake according to the present invention.

FIG. 2 is a cross-sectional view taken along a line II-II in FIG.

FIG. 3 is a front view of a manually-movable member, which is taken along the line III-II in FIG. 1;
It is I sectional drawing.

FIG. 4 is a side view of FIG. 3;

FIG. 5 is another embodiment of FIG.

6 is a front view of an automatic moving member, which is another embodiment of FIG.

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 6;

FIG. 8 is a front view of another embodiment of FIG. 1;

FIG. 9 is a front view of still another embodiment of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Press brake 3 Upper table 11 Lower table 15A, 15B Moving member 17A, 17B Slit

Claims (1)

(57) [Scope of request for utility model registration] 1. An upper table (3) is mounted on the upper part of the left and right side plates (5, 5), and a lower table (11) is mounted on the lower part.
In a press brake in which one of the upper table (3) and the lower table (11) is a movable table capable of moving up and down as appropriate, and the other table is a fixed table fixed to the side plates (5, 5), Slits (17A, 17B) opened on both left and right sides are provided symmetrically, and these left and right slits (17A, 17B) are
A press brake characterized in that a top (21) capable of adjusting the warpage of a fixed table during bending of a work (W) is provided so as to be position-adjustable.