JPS6199523A - Device for preventing middle droop of press brake - Google Patents

Abstract

PURPOSE:To perform rapidly the adjustment of crowning by attaching many eccentric cams to an axis in a box-type base frame and turning simultaneously these cams through a link-lever mechanism. CONSTITUTION:A die-attaching filler block 3 is vertically movably fitted to the upper part of a box-type base frame 1. Many eccentric cams 6 are disposed, which contact a circular arcuate liner 13 of the inner surface of block 3 and provide a projectingly curved crown increasing its height toward a center. The end of a revolving axis of cam 6 is fixed to a turning lever 17, and the end of lever 17 is rockably connected to a long connecting link 18. When the link 18 is moved in the longitudinal direction by operating a handle, the cam 6 is simultaneously turned to adjust the filler block 3 to the optimum crowning position. In this way, the crowning adjustment can be easily performed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is installed in the mold support part of the bed or ram of a press brake, and is used to prevent sagging in the bent material that occurs due to deflection of the bed or ram during pressurization. This invention relates to a device for preventing this phenomenon.

[Conventional technology and its problems]

Conventional anti-sag devices for press brakes prevent the sag of bent material caused by the deflection of the bed or ram during pressurization by preventing the sag from the mold support of the ram or bed (between the mold and the ram or bed). This can be prevented by arranging shims or squares along the entire length of the mold support member (the part where the molding occurs), and by applying the intervention of the shims or squares, a convex curved crowning that becomes higher toward the center of the mold support member is created. It was configured.

In this method, the height and thickness of all shims or shims are determined based on past experience or trials, depending on the type of material (workpiece) to be bent.
Since the adjustment had to be made one by one through error and error to obtain a predetermined crowning value, there was a problem in that the adjustment set work took a long time.

(Means for Solving the Problems) In order to solve the above-mentioned problems of the conventional art, the present invention has a large number of eccentric cams mounted in a long and narrow box-shaped base frame, and each of these eccentric cams is linked and connected. Lever 11
This feature is characterized in that the crowning adjustment of the filler block to which the mold is attached can be easily and quickly performed by rotating the filler block at the same time by 1t4.

(Embodiments of the Invention) Hereinafter, embodiments of the apparatus of the invention will be described with reference to the drawings. This embodiment shows an application example of a droop prevention device that is used by being placed and fixed on the upper surface of a bed B that supports the lower mold A of the press brake. This base frame 1 has an elongated box shape (an elongated box shape with an open top surface having approximately the same length as the base length) that is centered and fixed horizontally by centering bolts 2, and this base frame 1 is attached to a base plate 1a. And the front and rear side plates lb and I are fixed to this base plate with screws.
It is configured in a box structure with a groove-shaped cross section consisting of c.
A filler block 3 for attaching a mold is slidably fitted onto this box-shaped base frame 1 so as to be movable up and down (the sliding fitting portions of this filler block 3 are shown as 3a and 3b in Fig. 1). ).

The filler block 3 includes three pairs of side pieces 4.4 screwed to a portion of the base frame 1 projecting upward from the box opening at both ends and a middle portion thereof at intervals, and
The mold A is centered using the mold centering bolts 5 screwed into each pair of pieces.
This lower mold A is configured to be attached to the upper surface of the filler block 3.

Reference numeral 6 indicates the inner surface of the filler block 3 (arc-shaped upper liners 13 attached to the lower surface of the filler block 3 at equal intervals).
) as shown in FIG. They are arranged at equal intervals on both sides from the center position and are mounted on the same height line by rotating shafts 7 perpendicular to the longitudinal direction of the frame.

Each of these eccentric cams 6 has a roller portion 6a that is concentric with the axis of a rotating shaft 7 that is inserted and fixed at the center of the cam. (circumferentially touching the liner 11) and both end cam portions 6b which are eccentric with respect to the axis of this roller portion (the axis of the cam rotating shaft 7) with an eccentricity α.

6c (the cam portions 6b and 6c at both ends are arcuate upper liners 13 attached to the lower surface of the filler block 3 at equal intervals).
An O-ra as shown in FIG. The nut 8 is screwed onto the threaded end of the rotating shaft 7 which is in the shape of an eccentric cam, and is inserted into the center hole of the cam, and this nut is tightened to the end surface of the protrusion 6d via the washer 9. The eccentric cam 6 is tightened between the nut washer 9 and the large-diameter shaft portion of the rotating shaft 7 that receives the tightening force, as shown in FIG. Fixed.

Each of the eccentric cams 6 has both end cam portions 6b in circumferential contact with the inner surface of the filler block 3 (upper liner 13 pair).

The eccentricity α with respect to the rotation axis is set so that the outer circumferential height H from the rotation axis of 6C is the highest for the center eccentric cam, and the distribution on both sides gradually decreases toward the ends of the eccentric cam.
are different for each individual. That is, specifically, 81 in FIG.
The eccentric cam 6 at the center is designed to have the maximum eccentricity -α of 1.40 m, and the first distributed eccentric cam 6 at positions bl and b1 in the same figure has an eccentric amount α of 1,
38mm, a2. In the first distribution of 2 at the a2 position, the eccentric cam 6 has an eccentric amount α of 1°331 m, b2. b2
In the second distribution of position 2, the eccentric cam 6 has an eccentric amount α of 1.24 m, a3. The eccentric cam 6 in the first distribution of 3 at the a3 position has an eccentric amount α of 1.12 JllI.

b'3. The second distribution of 3 at position b3 has eccentric cam 6 eccentricity α of 0.9711*, a4. In the first distribution of 4 at the a4 position, the eccentric cam 6 has an eccentric amount α of 0.80
5. b4. In the second distribution of 4 at position b4, the eccentric cam 6 has an eccentric amount α of 0.60. , g,, a5. a5
The first distribution of position 5 is that the eccentric cam 6 has an eccentricity lα of 0.39 mm, b5. The second distribution of 5 at position b5 has an eccentric cam 6 designed with an eccentric amount α of 0.17 m, and the sixth one at position a6°a6 at both ends of the frame has an eccentric amount α of 0#II. Same y-'o-7&L
/ T h '2" h -c-') m jut I
By each eccentric cam portion, the filler block 3 is provided with a convex curved crowning that becomes higher from both ends toward the center.

As mentioned above, if a structure is adopted in which each eccentric cam 6 is tightened and fixed with a nut 8, each eccentric cam 6 must be rotated individually to prevent local wear of the upper and lower molds, the bed, or the ram. There is a practical advantage that this can be addressed through dynamic adjustment.

Reference numeral 17 designates a large number of rotary levers fixed to the rotating shaft end of each eccentric cam 6 (the shaft end protruding from the rear plate 1C of the base frame 1), and each lever end is connected to a frame disposed on the rear side of the frame 1. They are pivotally connected by one long connecting link 18 that is transversely movable in the length direction.

Reference numeral 20 denotes a link operating means that can move the connecting link 18 left and right within an arbitrary range in the length direction of the frame, and in this embodiment, a rotating handle is inserted and supported perpendicularly to one longitudinal end of the base frame 1. The shaft 21 and the M22 inside the dial scale attached to the front protruding shaft portion of the frame of this shaft.
(On the outer circumferential surface of this disc, there is a dial scale 22a from 0 to 1.4 that matches the index on the front of the frame.
), a rotational operation handle 23, a rotationally interlocking gear 24 fixed to the rear protruding shaft portion of the frame of the handle rotation shaft 21, and a frame near this gear shaft support. A swing gear 25 that meshes with the interlocking gear 24 which is pivotally supported on the rear side plate 10 as shown in FIG. (The bottle is supported as shown in the picture)
It is composed of.

Then, when the swing gear 25 is rotated by a rotation operation within the rotation range determined by the dial scale 22a of the handle 23, and the link 18 is laterally moved in the frame length direction by this small rotation, Due to this link movement, the rotation lever 17 is interlocked with the cam rotation shaft 7, so that all the eccentric cams 6 are rotated at the same time, and the filler block 3 can be adjusted and set at the optimum crowning position by this cam rotation.

In order to enable the handle to be locked after the crowning adjustment, a split collar 28 is attached to the handle rotation wheel 21, the diameter of which is reduced by a rotation operation bolt 27 so that the split part approaches the closing direction, as shown in FIGS. 6 and 8. It is fitted like this.

The embodiment described above is about a sagging prevention device installed on the top surface of the bed B of a press brake as shown in FIG. Needless to say, it is also applicable to

(Effects of the Invention) Since the press brake droop prevention device of the present invention uses the eccentric cam as described above, a large number of eccentric cams are simultaneously operated by the link actuating means via the link lever mechanism. By rotating, the optimum crowning adjustment can be easily and quickly and accurately performed even by non-specially skilled workers.In addition, the conventional shim/wedge force type ), there was a problem of edge load occurring due to the step between adjacent shims and grooves, but in the eccentric cam system of the present invention, the eccentric cam surface is a curved surface, so the problem of edge load can be avoided. There are advantages that can be achieved.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of the main parts of the droop prevention device for a press brake of the present invention, Fig. 2 is a front view showing the entire device, Fig. 3 is a plan view of Fig. 2, and Fig. 4 is a back view of Fig. 2, Fig. 5 is an explanatory diagram of the configuration of the eccentric cam, and Fig. 6 is the back view of Fig. 2.
A cross-sectional view of the line Vl-VI in the figure, Figure 7 is the ■■ of Figure 6.
Fig. 8 is a sectional view of the section taken along the line -■ in Fig. 7; DESCRIPTION OF SYMBOLS 1... Base frame, A... Lower mold of press brake, B... Bed of press brake, 3... Filler block, 3a, 3b... Slide fitting part, 6
...Eccentric cam, 6a...Concentric roller part, 6b,
6c...Eccentric corner portion at both ends, 6d...Protrusion opening,
7... Cam rotation axis, H... Outer circumference height from the rotation axis center of the eccentric cam portion, α... Eccentricity of the eccentric cam with respect to the rotation axis center, 8... Nut for tightening the cam, 11 .13...
Upper and lower liners, 17... Rotating lever, 18... Connecting link, 20... Link actuating means, 21,
-A throat 2 rotation axis/22°°° dial scale disk/2
3°°. Rotation operation handle, 24...Rotation interlocking gear, 25...
・Swivel gear. Figure 1 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] The filler block for mounting the mold is installed on the mold support part of the press brake bed or ram to prevent the sag of bent material that occurs from the deflection of the bed or ram during pressurization, increasing gradually toward the center. A device for preventing drooping of a press brake by attaching a convex curved crowning, comprising: a long and narrow box-shaped base frame into which the filler block is slidably fitted so as to be vertically movable; a large number of eccentric cams that circumferentially surround the inner surface of the filler block, which are distributed at equal intervals on both sides from the center position and are pivoted on the same height line, and provide a convexly curved crowning to the filler block;
A large number of rotary levers are fixed to the ends of the rotating shafts of the eccentric cams, one long connecting link is pivotally connected to each lever end and is movable laterally in the length direction of the frame, and this connecting link is connected to the frame length. The plurality of eccentric cams are arranged so that the outer circumferential height from the rotational axis of the eccentric cam part that is in contact with the inner surface of the filler block is equal to the center eccentricity. The amount of eccentricity with respect to the rotation axis is different for each cam so that the cam is highest and becomes lower as it goes to the end of the eccentric cam distributed on both sides. A press brake anti-sag device characterized in that the press brakes are rotated at the same time and can be adjusted and set to the optimum crowning position.