JPH06190446A - Crowing device for bending die in bender - Google Patents

Abstract

PURPOSE:To precisely crown bending dies in a smooth circular-arc shape without generating corrugated parts. CONSTITUTION:A wedge 11 is provided between the rear surface of a bending die 7 arranged on the tip end of a rocker arm 8a and the rocker arm 8a along the width direction of the bending die 7. An intruding depth of the wedge 11 in every part in the width direction of the bending die 7 is adjusted by deflecting the wedge 11 in the direction of intruding depth by an eccentric cam 18 of a rotating shaft 19 arranged on every part of the die. A bending die tightening device 12 by which the bending die is tightened with a spring force of a belleville spring 16 via a supporting rod 13 is provided. Plural parts in the width direction of the bending die 7 are elastically tightened to the rocker arm 8a by the device 12 via the wedge 11. Thus, the bending die 7 is adjusted into crown shapes copying deflecting depth on every part along the wedge 11 whose shape is deflected in the intruding depth direction. Further, the rocker arm 8a is provided with a tightening releasing device by which the bending die 7 is separated from the wedge 11 during adjustment to facilitate the adjusting operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending type crowning device in a bender for bending an end of a plate material.

[0002]

2. Description of the Related Art Conventionally, there is a bender in which a plate material is sandwiched between upper and lower dies and a portion of the plate material protruding from the upper and lower dies is pushed up by a bending die to end-bend. In this type of bender, the mold width is long, and the stress acting on the bending mold is different between the center part and the both end parts in the mold width direction, so that the tip edge of the bending mold is a straight line,
You cannot bend along a straight line.

Therefore, in general, the tip edge of the bending die is adjusted to a crown (middle height) shape as shown in FIG. 9 by a crowning device. That is, a large number of crowning rods 42 are arranged side by side in the die width direction through the bending die 40 attached to the tip of the rocker arm 41, and the amount of protrusion of each crowning rod 42 is adjusted, so that the bending die 40 has a desired crown. Give shape. The amount of protrusion of each rod 42 is adjusted by the feed screw mechanism 43. In this case, the lead of the screw of each feed screw mechanism 43 is made slightly larger than that of the crowning rod 42 on the center side. Therefore, by rotating each crowning rod 42 synchronously via the sprocket 44 provided at the rear end, the curvature of the virtual curve passing through the tip of each crowning rod 42 changes. Thereby, the amount of protrusion between the crowning rods 42 can be adjusted easily and accurately.

[0004]

However, in the conventional structure shown in FIG. 9, each crowning rod 42 is directly bent by the bending die 40.
The pushing force does not act on the portion between the pitches of each crowning rod 42, and the bending die 40 pulls the bending die 40 toward the rocker arm 41 side. No.) tightening force is applied. Therefore, the shape of the tip edge of the bending die 40 has a corrugated shape in which the abutting portion of each crowning rod 42 protrudes and the portion between the rods is recessed as shown by a chain line a in the figure, and the shape of the crown is accurate. Can't get
For this reason, it is difficult to perform bending along a straight line with high accuracy.

An object of the present invention is to provide a bending type crowning device in a vendor which can perform accurate crowning.

[0006]

According to the bending die crowning device of the present invention, a section perpendicular to the die width direction is tapered between the rocker arm and the back surface of the bending die arranged at the tip of the rocker arm. A wedge bending adjusting device and a bending die clamping device are provided by interposing the wedge in the width direction of the die. The wedge deflection adjusting device is a device that bends the wedge in the approaching direction and adjusts the depth of entry of the wedge in each portion in the width direction of the bending die. The bending mold tightening device is a device that elastically tightens a plurality of bending molds at a plurality of positions in the width direction on a rocker arm via wedges.

[0007]

According to this structure, since the bending die is clamped to the rocker arm through the wedge, the protrusion amount of each portion in the die width direction is the protrusion amount according to the penetration depth of each portion of the wedge. Also,
The wedge is adjusted to a bent state by adjusting the depth of penetration at each portion in the mold width direction by a wedge bending adjusting device. In this case, unlike the bending die, the wedge does not receive a tightening force in the opposite direction between the portions pressed by the wedge deflection adjusting device, and therefore even if the pressing portion is intermittent, its elasticity causes the corrugated portion to move. It bends into a highly accurate arc-shaped curve that does not occur. In this way, since the bending die is clamped to the rocker arm via the wedge that is smoothly bent in the depth direction of penetration, the crown shape of the bending die also has a smooth shape with no wavy portion.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. A bender in which the crowning device of this embodiment is used includes a bender main body 1 shown in FIGS. 6 and 7 in a side view and a front view, and a plate material feeding device 2 shown by a chain line in FIG. The vendor main body 1 has an upper die 4 attached to a ram 3 and driven up and down, a lower die 5 fixed to a main body frame 6, and a protruding portion W1 of a plate material W sandwiched by these upper and lower dies 4, 5 upward. Alternatively, a bending die 7 that bends downward is provided.

The bending die 7 is attached to a bending die holder 8a at the tip of a rocker arm 8, and the rocker arm 8 is vertically swung by a plurality of hydraulic cylinders (not shown) and is pushed into the upper and lower dies 4, 5. It is possible to move back and forth. The upper die 4 is divided into a large number of segments 4a in the die width direction, and a die width changing mechanism 9 for selecting this segment 4a.
The width can be changed by.

The bending die holder 8a has a C-shaped cross section, and the bending die 7 is arranged on the die receiving step portion 10 at the tip thereof as shown in FIG. Between the front surface of the die receiving step portion 10 and the back surface of the bending die 7, a wedge 11 having a width narrowing downward is interposed along the width direction of the bending die 7. As shown in FIG. 1 (C), the bending die holder 8a is provided at a plurality of positions in the width direction of the bending die 7 by the bending die clamping device 12 via the wedge 11.
It is elastically fastened to the front surface of the mold receiving step 10. The bending die clamping device 12 inserts a plurality of support rods 13 respectively connected to a plurality of widthwise positions of the bending die 7 from the through hole 11a of the wedge 11 to the bending die holder 8a, and attaches to the outer periphery of the supporting rod 13. A large number of disc springs 16 are provided so as to be stacked in the axial direction. The disc spring 16 is a bending die holder 8a.
A preload state is interposed between the front wall of the inner spring mounting space 14 and the receiving member 15 at the rear of the support rod 13. Since the through hole 11a has a vertically long shape that is long in the depth direction of the wedge 11 as shown in FIG. 1D, the wedge 11 can be bent vertically without being hindered by the support rod 13.

The wedge 11 is adapted to adjust the penetration depth at each portion in the width direction of the bending die 7 by being bent in the penetration depth direction by a wedge flexure adjusting device 17 shown in FIG. 1 (A). That is, the wedge deflection adjusting device 17 inserts a plurality of rotary shafts 19 each having an eccentric cam 18 at the front end into each through hole 20 of the bending die holder 8a, and rotatably supports the rotary shafts with a bearing 21. The input sprocket 22 mounted on the rear end portion of 19 is rotationally driven by the rotational drive mechanism 23 shown in FIG. The eccentric cam 18 is shown in FIG.
As shown in FIG. 3, the cam body 18b is formed by projecting a columnar cam body 18b at a position O1 deviated from the rotation center O of the columnar cam base 18a concentric with the rotation shaft 19.
8b, as shown in FIG. 1B, is loosely fitted in the laterally long hole 24a of the cam follower 24 embedded in the back side of the wedge 11. As shown in the horizontal sectional view of FIG. 5, the rotary shafts 19 are arranged at a predetermined interval over substantially the entire width of the bending die holder 8a. Further, the number of teeth of each input sprocket 22 is set so that the number of teeth of the input sprocket 22 increases as the distance between the sprockets 22 on both sides is greater than that of the central sprocket 22.

The rotary drive mechanism 23, as shown in FIG. 4, has a drive motor 25 provided on the back side of the bending die holder 8a.
Output gear 26, an intermediate gear 27 meshing with the output gear 26, an output sprocket 28 coaxial with the intermediate gear 27, and a wedge deflection adjusting device 17 from the sprocket 28.
Of the input sprocket 22.

As shown in FIG. 2, the bending die holder 8a has a tightening releasing device for releasing the tightening of the bending die 7 against the urging force of the bending die tightening device 12 (FIGS. 1C and 4). 30 are provided. The tightening release device 30 is connected to the cylinder 31 mounted on the bending die holder 8a and the advancing / retreating rod 32 of the cylinder 31 and penetrates the bending die holder 8a through the through hole 11b of the wedge 11 to contact the rear surface of the bending die 7. It is composed of a pressing rod 33 that contacts. Since the through hole 11b of the wedge 11 is formed vertically long in the depth direction of the wedge,
The wedge 11 can be bent up and down without being hindered by the pressing rod 33. It should be noted that the left and right ends of the wedge 11 are provided with positioning holes 11c formed on the back surface thereof as shown in FIG. 3, and tabs 3 projectingly provided on the front surface of the die receiving step portion 10 of the bending die holder 8a.
The vertical movement is prevented by engaging 4 with each other.

Next, the crown shape adjusting operation of the bending die 7 will be described. First, before starting the adjustment, the advancing / retreating rod 32 of the cylinder 31 in the tightening release device 30 (FIG. 2) is advanced to resist the biasing force of the disc spring 16 of the bending die tightening device 12 (FIG. 1 (C)). Then, the bending die 7 is slightly pushed forward. As a result, the bending die 7 is separated from the wedge 11, and resistance for adjusting the penetration depth of the wedge 11 by the bending die 7 is eliminated.

Then, the rotary drive mechanism 23 shown in FIG. 4 is started to operate the wedge deflection adjusting device 17. That is, the rotation of the drive motor 25 is controlled by the output gear 26, the intermediate gear 27,
It is transmitted to each input sprocket 22 of the wedge deflection adjusting device 17 via the output sprocket 28 and the endless chain 29.
As a result, the rotary shafts 19 rotate, and the eccentric cams 18 at their front ends adjust the depth of penetration of each part of the wedge 11. In this case, the number of teeth of each input sprocket 22 is
Since the wedges 11 corresponding to the central portions of the wedges 11 are gradually increased in number, the wedges 11 are shown in a longitudinal sectional view in FIG. 8A by the above driving. As described above, the penetration depth is adjusted to gradually increase from both ends to the center. Since the protrusion amount of the bending die 7 to the front is larger in a portion where the wedge 11 is deeply inserted than in a portion where the wedge 11 is deep, the entire bending die 7 is horizontally cross-sectionally shown in FIG. The crown shape is adjusted as shown in.

Since the crowning in this case is not performed by directly pressing the respective parts of the bending die 7 with the rods but adjusting the crowning through the wedges 11 which are bent in the depth direction, the crown shape of the bending die 7 is smooth. Will be things. That is, the wedge 11
Unlike the bending die 7, since a tightening force in the opposite direction does not act between the portions pressed by the wedge deflection adjusting device 17, even if the pressing portion is intermittent, a highly accurate arc-shaped curve that does not generate a wavy portion is formed. Further, the wedge 11 is bent by the elasticity of the material. In this way, since the bending die 7 is clamped to the rocker arm 8 via the wedge 11 that is smoothly bent in the depth direction of the approach, the crown shape of the bending die 7 is a smooth shape that does not generate a corrugated portion. In this way, accurate crowning can be performed.

[0017]

According to the bending die crowning device of the bender of the present invention, a wedge extending in the width direction of the bending die is interposed between the back surface of the bending die and the rocker arm, and the wedge is bent in the depth direction of penetration. Since the entrance / exit is adjusted in each part in the width direction of the bending die, it is possible to accurately crown the smooth arc-shaped curve without the wavy shape.

[Brief description of drawings]

FIG. 1A is a sectional view showing a wedge deflection adjusting device in an embodiment of the present invention, FIG. 1B is a front view showing a part of the wedge, and FIG. 1C is a sectional view showing the bending die tightening device. Figure,
(D) is a front view showing a part of a wedge through which the support rod penetrates.

FIG. 2 is a cross-sectional view showing the tightening release device.

FIG. 3 is a cross-sectional view showing a position regulating structure at both ends of the wedge.

FIG. 4 is a front view showing the rotation drive mechanism.

FIG. 5 is a horizontal sectional view showing a rocker arm tip portion on which the crowning device is mounted.

FIG. 6 is a side view of a vendor main body on which the crowning device is mounted.

FIG. 7 is a front view of the vendor main body.

FIG. 8A is a vertical cross-sectional view of the rocker arm front part showing a change in bending of the wedge, and FIG. 8B is a horizontal cross-sectional view of the rocker arm front part showing a change in protrusion of the bending die.

FIG. 9 is a horizontal sectional view showing a conventional example.

[Explanation of symbols]

7 ... Bending die, 8 ... Rocker arm, 8a ... Bending die holder, 11 ... Wedge, 12 ... Bending die tightening device, 17 ... Wedge flexure adjusting device, 23 ... Rotation drive mechanism, 30 ... Tightening release device

Claims (1)

[Claims] 1. A wedge having a tapered cross section perpendicular to the die width direction is interposed along the die width direction between the rocker arm and the back surface of a bending die disposed at the tip of the rocker arm,
A wedge bending adjusting device is provided which bends the wedge in the advancing direction to adjust the advancing depth of the wedge in each portion in the width direction of the bending die,
A bending die crowning device in a bender provided with a bending die clamping device that elastically clamps a plurality of widthwise portions of the bending die to the rocker arm via the wedges.