JPH0375245B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a press brake for bending plate materials, and more particularly to a press brake that can adjust the curvature of a fixed apron.

(Prior technology) A press brake has a fixed apron fixed on both left and right sides to the left and right side frames of a C-shape, and a movable apron (ram) that is movable up and down facing the fixed apron is attached to the side frame. It is common to move up and down using a hydraulic cylinder or the like.

In a press brake with the above configuration, if a mold is attached to each of the fixed apron and the movable apron to bend the plate, a problem with the structure of the press brake is that the center Phenomenon where the side bends loosely,
In other words, it is known that a drooping phenomenon occurs.

Therefore, in the past, a large number of adjusting devices including wedge members etc. were interposed between the fixed apron or the movable apron and the mold, and the wedge members of each adjusting device were adjusted to adjust the curvature of the mold in advance. Generally, a structure is adopted in which the sagging phenomenon is prevented by doing so.

(Problems to be Solved by the Invention) In a conventional configuration in which an adjustment device is interposed between a fixed apron or a movable apron and a mold, the maximum dimension between the fixed apron and the movable apron is It is necessary to increase the size by the amount of the intervening part, which causes problems such as the side frame and the overall height dimension increasing accordingly.

The present invention has been made in view of the above-mentioned conventional problems, and aims to provide a press brake that can adjust the curvature of a mold without using a conventional adjustment device.

(Example) Referring to FIGS. 1 and 2, the press brake, like a general press brake, has left and right sides of the fixed apron 1 on the upper side of the C-shaped left and right side frames 2L and 2R. A movable apron 4 is provided below the fixed apron 1 so as to be movable up and down. Note that whether the fixed apron 1 is provided on the upper side or the lower side is merely a matter of design, and in this embodiment, the case where the fixed apron 1 is provided on the upper side is exemplified. be.

As shown in FIG. 2, front and rear support plates 3, 5 are arranged at the front and rear of the fixed apron 1, and the left and right sides of both support plates 3, 5 are connected to the left and right side frames 2L, 2R. It is fixed.

A plurality of rectangular openings 10 are provided in the support plates 3 and 5 at appropriate intervals in the left-right direction as shown in FIG. As shown in the figure, a sliding body 7 whose movement in the vertical direction is restricted is provided so as to be movable in the left and right directions.

As shown in more detail in FIGS. 3 to 5, each opening 1 provided in the support plates 3, 5
Eccentric portions 9E are provided at the front and rear of each of the plurality of eccentric shafts 9 which are rotatably fitted to the fixed apron 1 in accordance with 0, respectively. , is rotatably supported by the sliding body 7. A square hole 11 is formed in the front eccentric portion 9E of each of the eccentric shafts 9, and a disk-shaped fixing plate 13 is integrally attached thereto. A clamp jaw 15 which can be press-fixed to the support plate 3 is attached via a tightening bolt 14.

In the above configuration, when a tool is fitted into the square hole 11 of each eccentric shaft 9 and the eccentric shaft 9 is rotated, the eccentric portion 9E of the eccentric shaft 9 is displaced vertically and horizontally with respect to the eccentric shaft 9. Become. The displacement in the left-right direction is absorbed by the sliding body 7 moving in the left-right direction with respect to the openings of the support plates 3 and 5. Since the vertical movement of the sliding body 7 is restricted, a relative vertical displacement occurs between the support plates 3 and 5 and the fixed apron 1.

More specifically, referring to FIG. 6 which shows a simulated principle, both ends of the fixed apron 1 and the front and rear support plates 3 and 5 are connected to the side frame 2.
Since it is fixed at L and 2R, when the eccentric shaft 9 is rotated in the direction of arrow T in Fig. 6,
Since the eccentric portion 9E of the eccentric shaft 9 is eccentric by e, if the fixed apron 1 is made entirely of steel,
The front and rear support plates 3 and 5 are elastically deformed upward by an amount of eccentricity e. However, since the fixed apron 1 is an elastic body, it receives a reaction force when the support plates 3 and 5 are elastically deformed upward by the eccentric amount e, and this reaction force causes the fixed apron 1 to It is relatively elastically deformed downward.

Therefore, when the eccentric shaft 9 is rotated in the direction of the arrow T in FIG. 6 as described above, the support plates 3 and 5 are relatively deformed slightly upward, and the reaction force causes the fixed apron to 1 is relatively deformed slightly downward, and the sum of the upward deformation of the support plates 3 and 5 and the downward deformation of the fixed apron 1 is equal to the eccentricity e. It is.

Therefore, the amount of rotation of each eccentric shaft 9 is adjusted individually, and the fixed apron 1 relative to the support plates 3 and 5 is fixed.
By adjusting the relative vertical displacement of the fixed apron 1, it is possible to adjust in advance so that the center portion of the fixed apron 1 in the left-right direction projects downward with respect to the support plates 3 and 5.

That is, even in a configuration in which a mold is directly attached to the fixed apron 1, by adjusting the curvature of the fixed apron 1, it is possible to prevent the sagging phenomenon during bending of the plate material.

Therefore, when attaching the mold to the stationary apron 1, even if the mold is directly attached to the stationary apron 1 without the intervention of an adjustment device having a wedge member or the like, the sagging phenomenon can be addressed, and the above-mentioned problem can be solved. The overall height can be reduced by the height dimension of the adjustment device.

(Effects of the Invention) As can be understood from the description of the embodiments described above, according to the present invention, even if the mold is directly attached to the fixed apron without the intervention of a conventional adjustment device, etc. , the fixed apron itself can be curved, and the phenomenon of sagging can be coped with. In other words, the conventional adjustment device can be omitted, the overall height dimension can be reduced, and miniaturization can be achieved.

[Brief explanation of drawings]

The accompanying drawings illustrate embodiments of the invention, and
Fig. 1 is a front view of a press brake embodying the present invention, Fig. 2 is a side view of the press brake, Fig. 3, Fig. 4,
FIG. 5 is a side sectional view, a front view, and a front sectional view of the main part, that is, the section A in FIGS. 1 and 2, respectively. FIG. 6 is a diagram illustrating the curvature in a simulated manner. 1... Fixed apron, 3... Front support plate, 5... Rear support plate, 7... Sliding body, 9
...Eccentric shaft.

Claims (1)

[Claims] 1. A fixed apron 1 whose left and right sides are fixed to the left and right side frames 2L, 2R, and a movable apron 4 that is movable in directions approaching and away from the fixed apron 1, and both the aprons 1, 4
In a press brake equipped with a mold for bending plate materials, the left and right sides of the respective support plates 3 and 5 arranged at the front and rear of the fixed apron 1 are fixed to the side frames 2L and 2R, and the left and right sides are fixed to the side frames 2L and 2R. A plurality of eccentric shafts 9 that are rotatably fitted to the fixed apron 1 are provided with eccentric portions 9E protruding from the front and rear portions of the plurality of eccentric shafts 9, which are spaced apart from each other in the direction of the fixed apron 1. Each of the sliding bodies 7 is provided in a plurality of openings 10 formed in the openings 10 so as to be movable in the left-right direction, and the vertical movement of each sliding body 7 is restricted. A press brake characterized in that it is rotatably supported on each of the sliding bodies 7.