JP2012143807A - Bending apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly accurately correct deflection by eliminating problems caused by using a hydraulic cylinder.SOLUTION: A workpiece W is bent with a die D and a punch P on the side of an upper table 9 by elevating a lower table 7 using elevating and lowering cylinders 11, 13. The center axial lines R of rotation of the rotating shafts 37 of eccentric rotary plates 35 housed in the opening part 9c of the lower table 9, are eccentric to the center axial lines Q of the eccentric rotary plates 35, the rotating shafts 37 of eccentric rotary plates 35 are rotatably supported with rotating shaft support frames 39, 41 which are arranged so as to hold both surfaces of the lower table 9 between them. When bending the workpiece W, the upper table 7 and the punch P, and the lower table 9 and the die D are deformed into a concave shape by deflection caused by pressurization reaction at the respective middle parts in the right and the left direction around the working region. At this time, the eccentric rotary plate 35 is rotated and the arc surface 31a of an upper block 31 in the opening part 9c of the lower table 9 is pressurized upward, consequently the upper surfaces of the lower table 9 and of the die D are deformed into a convex shape, thereby canceling. the concave deflection.

Description

  The present invention relates to a bending apparatus that bends a plate-shaped workpiece between a pair of molds by moving a pair of mold support members that respectively support the pair of molds toward each other.

  2. Description of the Related Art Conventionally, a press brake as a bending apparatus, for example, as described in Patent Document 1 below, moves a lower table provided with a lower mold closer to an upper table provided with an upper mold. A plate-shaped workpiece set on a mold is bent. At that time, left and right table elevating cylinders for elevating and lowering the lower table are arranged on the left and right sides of the lower table, respectively.

  The same is true for press brakes that replace the ascending bender with the descending type. In other words, the plate-like workpiece set on the lower die is bent by moving the upper table having the upper die closer to the lower table having the lower die. At that time, left and right table elevating cylinders for raising and lowering the upper table are arranged on both the left and right sides of the upper table, respectively.

  When bending, the upper table and the lower table are subjected to the pressure reaction force through the workpiece interposed between the upper and lower molds. Then, bending deformation occurs so that the central part in the left-right direction is recessed with the processing part as the center. In order to correct this deformation, left and right deflection correction cylinders are provided.

Japanese Patent No. 3157903

  However, in the above-described conventional bending apparatus, since the hydraulic cylinder is used when correcting the deflection of the upper table and the lower table, maintenance and inspection of the hydraulic equipment is necessary, and depending on the bending conditions, There is a possibility that high-precision deflection correction cannot be performed due to vibration during deflection correction.

  Accordingly, an object of the present invention is to solve the problems caused by using a hydraulic cylinder and to perform highly accurate deflection correction.

  The present invention is a bending apparatus for bending a plate-shaped workpiece between the pair of molds by moving a pair of mold support members that respectively support the pair of molds toward each other. Drive means for moving the pair of mold support members toward and away from each other is disposed on both sides in the vertical direction, and the pair of positions corresponding to the pair of molds on the inner side in the bending length direction of the workpiece with respect to each drive means. The pair of mold supports at the time of processing is provided by providing a pressed surface on at least one of the mold support members and pressing the pair of molds while moving while contacting the pressed surface. A deflection correcting member for correcting the deflection of the member is provided.

  According to the present invention, the bending correction member is pressed against the pair of molds while moving while being in contact with the pressed surface provided on at least one of the pair of mold support members. Since the bending of the mold support member is corrected, the problem caused by using the hydraulic cylinder can be solved and highly accurate bending correction can be realized.

It is a front view of the press brake which shows one Embodiment of this invention. It is AA sectional drawing of FIG. It is explanatory drawing which shows the state which rotated the eccentric rotating board so that the upper surface of a lower table may become convex shape at the time of the bending process using the press brake of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a press brake 1 as a bending apparatus according to an embodiment of the present invention has an upper table 7 fixed to upper portions of left and right side plates 3, 5 and disposed below the upper table 7. A certain lower table 9 can be moved up and down by left and right lifting cylinders 11 and 13 as driving means coupled to lower portions of the side plates 3 and 5.

  An upper die punch P is detachably attached to a position of the upper table 7 facing the lower table 9 via a punch attachment bracket 15, and a die attachment bracket is attached to a position of the lower table 9 facing the upper table 7. A die D serving as a lower die is detachably attached via 17.

  Here, the punch P and the die D constitute a pair of molds, and the upper table 7 and the lower table 9 constitute a pair of mold support members that respectively support the pair of molds.

  The lower table 9 includes projecting portions 9a whose upper portions project in both the left and right directions (the bending direction of the workpiece W) in FIG. 1, and the piston rods 19 and 21 of the elevating cylinders 11 and 13 are disposed below the projecting portions 9a. The tip (upper end) is connected. Spherical recesses 19a and 21a are formed at the upper ends of the piston rods 19 and 21 of the elevating cylinders 11 and 13, respectively. On the other hand, support seats 23 and 25 are attached to the left and right lower portions of the lower table 9, and spherical convex portions 23 a and 25 a are formed at the lower ends of the support seats 23 and 25.

  The spherical convex portions 23a and 25a of the support seats 23 and 25 are supported by the spherical concave portions 19a and 21a of the piston rods 19 and 21, and in this supported state, the piston rods 19 and 21 and the support seats 23 and 25 are The bolts 27 and 29 are connected. Thereby, a slight inclination of the lower table 9 is allowed with respect to the lifting cylinders 11 and 13.

  The lower table 9 includes a bulging portion 9b that bulges downward between the left and right projecting portions 9a. The lower table 9 has a rectangular opening when viewed from the front at a symmetrical position with respect to the center of the bulging portion 9b in the left-right direction. Part 9c is formed. The upper block 31 is mounted on the upper surface 9cu of the opening 9c, and the lower block 33 is mounted on the lower surface 9cd of the opening 9c.

  And between the upper block 31 and the lower block 33, the circular eccentric rotation board 35 which is a disk-shaped member as a bending correction member is arrange | positioned rotatably. A rotation shaft 37 whose rotation center axis R is eccentric with respect to the center axis Q is integrally attached and fixed to the eccentric rotation plate 35. The rotating shaft 37 is orthogonal to the direction in which the lower table 9 moves up and down in the vertical direction with respect to the upper table 7 and is orthogonal to the bending length direction of the workpiece W (left-right direction in FIG. 1). In FIG. 1, it extends along a direction perpendicular to the paper surface (left and right direction in FIG. 2).

  As shown in FIG. 1, the rotation shaft 37 is arranged so that the rotation center axis R is positioned above the center axis Q and the axes R and Q are positioned on the same straight line in the vertical direction. The outer peripheral surface is in contact with both an arc surface 31 a as a pressed surface formed on the lower surface of the upper block 31 and an arc surface 33 a formed on the upper surface of the lower block 33.

  Here, the curvature of each arc surface 31a, 33a is sufficiently smaller than the curvature of the circular outer peripheral surface of the eccentric rotating plate 35. That is, the circular arc surfaces 31 a and 33 a are curved surfaces that are sufficiently gentler than the outer peripheral surface of the eccentric rotating plate 35. In addition, it is good also as a planar shape used as a horizontal surface instead of the circular arc shape of the circular arc surfaces 31a and 33a. Further, the eccentric rotating plate 35 may not be in contact with the circular arc surface 33 a of the lower block 33.

  As shown in FIG. 2, the rotary shaft 37 described above is rotatably inserted and supported in through holes 39a and 41a of a pair of rotary shaft support frames 39 and 41 arranged so as to sandwich the lower table 9 from both sides. . In this state, the lower table 9 can move in the vertical direction in FIG. 2 with respect to the rotary shaft support frames 39 and 41, and moves up and down together with the rotary shaft support frames 39 and 41 by driving the lifting cylinders 11 and 13.

  A servo motor 45 is connected to the end of the rotary shaft 37 on the side protruding from the right rotary shaft support frame 41 in FIG. 2 via a speed reducer 43, and the servo motor 45 is driven and controlled by a controller 47. Is done. In addition, the control device 47 controls the driving of the left and right lifting cylinders 11 and 13 by outputting a signal to an electric device that adjusts the hydraulic pressure.

  Next, the operation will be described. When a pressure fluid is supplied to the left and right table elevating cylinders 11 and 13 with the workpiece W placed on the die D and the piston rods 19 and 21 are operated to protrude, the lower table 9 rises and approaches the upper table 7. Moving. At this time, the rotary shaft support frames 39 and 41 connected to the lower table 9 via the rotary shaft 37 also move upward together with the lower table 9.

  As the lower table 9 moves upward, the die D moves closer to the punch P, and the punch P enters the V-shaped groove of the die D by a predetermined dimension. As a result, the lower surface of the work W comes into contact with the left and right shoulders of the V-shaped groove of the die D as shown in FIG. 2, and the central portion of the work W is in the V-shaped groove of the die D by the tip of the punch P. Can be folded.

  During this bending process, the upper table 7 and the lower table 9 are bent in the vertical direction by the pressure reaction force received from the workpiece W interposed between the tables 7 and 9, and the upper table 7 and the punch P The lower surface is deformed into a concave shape, and the upper surface of the lower table 9 and the die D is deformed into a concave shape.

  At this time, in the present embodiment, the control device 47 drives and controls the servo motor 45 in accordance with the operation of each of the table elevating cylinders 11 and 13 described above, and the rotating shaft 37 is moved together with the eccentric rotating plate 35 via the speed reducer 43. Rotate in the left or right direction from the state of FIG.

  At this time, the eccentric rotating plate 35 rotates around the rotation center axis R (center axis of the rotation shaft 37) that is eccentric with respect to the center axis Q. Therefore, when the eccentric rotating plate 35 rotates, for example, counterclockwise in FIG. 1, the outer peripheral surface located at the upper end rotates while moving in contact with the circular arc surface 31a, as shown in FIG. Move and displace upward from the state.

  Due to the upward displacement of the eccentric rotating plate 35, the eccentric rotating plate 35 presses the upper block 31 upward, and this pressing force is transmitted to the lower table 9 via the upper surface 9cu of the opening 9c. At this time, the outer peripheral surface located at the lower end of the eccentric rotating plate 35 is in a state of being separated from the circular arc surface 33 a of the lower block 33.

  The lower table 9 receives the transmitted upward pressing force, and its upper surface and the upper surface of the die D are deformed into a convex shape.

  Therefore, the convex deformation of the upper surface of the lower table 9 and the upper surface of the die D causes the concave deformation of the upper table 7, the lower surface of the punch P, the lower table 9, and the upper surface of the die D due to the pressure reaction force described above. This offsets the linearity of the upper table 7, the lower surface of the punch P, the lower table 9, and the upper surface of the die D.

  At this time, in this embodiment, the operation of canceling the concave deformation due to the pressure reaction force by the convex deformation is performed by the upward pressing force by the rotation of the eccentric rotating plate 35 without using the hydraulic cylinder. This eliminates the problems associated with using hydraulic cylinders, that is, complicated maintenance and inspection work for hydraulic equipment, and depending on the bending conditions, vibration during vibration correction and high-precision deflection correction cannot be performed. It is easy to handle and can realize highly accurate deflection correction.

  The eccentric rotating plate 35 can be maximized in the protruding amount of the above-described convex shape when rotated 180 degrees from the state of FIG. 1, and the protruding amount is determined by the right and left lifting cylinders 11, It changes suitably according to the bending load which 13 gives. Thus, a convex deformation corresponding to the concave deformation is generated, and the linearity of the table 7, the lower surface of the punch P, the lower table 9, and the upper surface of the die D is always maintained even if the processing conditions are changed. Can do.

  Further, in this embodiment, the deflection correcting member is constituted by an eccentric rotating plate 35 having a rotating shaft 37, and the rotating shaft 37 is provided at a position eccentric with respect to the center of the eccentric rotating plate 35. It is configured to rotate eccentrically. Thereby, the linearity of the upper table 7, the lower surface of the punch P, the lower table 9, and the upper surface of the die D can be maintained with a simple configuration in which the rotating shaft 37 is attached to the eccentric rotating plate 35.

  In the above-described embodiment, when the upper surface of the lower table 9 and the upper surface of the die D are deformed in a convex shape, the circular eccentric rotating plate 35 is used, but the present invention is not limited to this. For example, instead of the circular eccentric rotating plate 35, for example, an elliptical, oval, or arm-shaped member that is rotationally displaced by the rotation of the rotating shaft 37 is attached to the rotating shaft 37, and these members allow the upper block 31 to be You may make it press the arc surface 31a and the horizontal surface replaced with the arc surface 31a toward the upper direction.

  In the above-described embodiment, the eccentric rotating plate 35 is arranged at two symmetrical positions with respect to the horizontal center of the lower table 9, but may be arranged at one central position in the horizontal direction. .

  Further, in the above-described embodiment, the convex deformation for canceling the concave deformation due to the pressure reaction force is generated in the lower table 9. Alternatively, the upper table 7 may be provided with an eccentric rotating plate 35 having a rotation shaft 37 so that the upper table 7 is convexly deformed downward, and the upper table 7 and the lower table 9 You may comprise so that both may carry out convex deformation.

1 Press brake (bending machine)
7 Upper table (a pair of mold support members)
9 Lower table (a pair of mold support members)
11, 13 Lifting cylinder (driving means)
31a Arc surface of the upper block (pressed surface)
35 Eccentric rotating plate (disc-like member, deflection correction member)
37 rotating shaft P punch
D die (a pair of molds)
W Work

Claims (2)

  A bending apparatus for bending a plate-shaped workpiece between the pair of molds by moving a pair of mold support members that respectively support the pair of molds closer to each other on both sides in the bending length direction of the workpiece. Drive means for moving the pair of mold support members toward and away from each other, and the pair of mold support members at positions corresponding to the pair of molds on the inner side in the bending length direction of the workpiece with respect to the drive means. By providing a pressed surface on at least one of these and pressing the pair of molds while moving while contacting the pressed surface, the pair of mold support members can be bent at the time of processing. A bending apparatus provided with a bending correction member for correction.   The deflection correcting member is constituted by a disk-shaped member having at least a rotating shaft extending in a direction orthogonal to the approaching / separating movement direction, and the rotating shaft is provided at a position eccentric with respect to the center of the disk-shaped member. The bending apparatus according to claim 1, wherein the disk-shaped member rotates eccentrically.

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