Press machine

Abstract

[Problem] To provide a press machine capable of correcting crowning without complicating a device structure or increasing cost. [Solution] The press machine performs processing on a workpiece between an upper mold 22 and a lower mold 32 that is placed on an adjustment table 40. The adjustment table 40 includes: a control rod 43 extending in a width direction X and having a plurality of drive pins 44 arranged along the width direction X; a rod drive part 45 that drives the control rod 44 in the width direction; and a plurality of adjustment blocks arranged along the width direction X. Each of the adjustment blocks 42 has a first tapered plate 50 having a first tapered surface 50a and a slot 50b inclined at a predetermined angle α with respect to a width direction in which a drive pin 44 is guided, and a second tapered plate 51 having a second tapered surface 51a complementary to the first tapered surface 50a and facing the first tapered surface 50a. An inclination angle α of a slot 51b of at least one adjustment block 42 is different from the inclination angle α of the slot 50b of at least one other adjustment block 42.

Description

press machine

[0001] The present invention relates to a press machine such as a panel bender or a press brake, and more particularly to a press machine capable of correcting and rectifying crowning that occurs on a table during bending.

[0002] FIG. 5 shows a conventional press machine 101. The press machine 101 includes a side frame 110, an upper table 120 that holds an upper die 122, a lower table 130 that holds a lower die 132, and a table drive means 111, such as a servomotor, fixed to the side frame 110. The upper table 120 is lowered by driving a drive shaft 112 of the table drive means 111, thereby clamping and bending a workpiece placed between the upper and lower dies 122, 132. The applied pressure causes concave deflection (crowning), as shown by imaginary lines C1 and C2, in the upper and lower tables 120, 130, resulting in a problem of reduced workpiece processing accuracy. This problem becomes particularly pronounced when the width dimension of the workpiece or the upper and lower tables 120, 130 is large or when the applied pressure is large.

[0003] Known methods for addressing the above problem include, for example, Patent Documents 1 and 2. Patent Document 1 reduces crowning by using the biasing force of multiple deflection correction cylinders located at the widthwise middle of the lower table. Patent Document 2 reduces crowning by changing the elastic force of the upper and lower tables in the widthwise direction using multiple elastic devices embedded at the widthwise middle of the upper and lower tables.

[0004] Another known measure to combat crowning is the press machine 201 shown in Figure 6. In the press machine 201, the lower table 230 is made up of multiple tables 231 to 233 stacked one on top of the other, and these are connected by a connecting pin 240 near the center, thereby reducing crowning of the middle table 231.

[0005] Japanese Patent Laid-Open No. 5-329549 Japanese Patent Laid-Open No. 2004-136366

[0006] However, in the press machine of Patent Document 1, the cost increase due to the addition of a deflection correction cylinder is excessive. In the press machine of Patent Document 2, the elastic device has a complex and precise structure, making it vulnerable to malfunction, and the elastic device has a limited load capacity, making it inapplicable to press machines with large pressing forces. The method of Figure 6 requires a number of connecting pins 240 (approximately 2 to 8) corresponding to the width dimension of the press machine 201, but the through holes for each connecting pin 240 must be formed in each table 231 to 233 with extremely high positional accuracy, resulting in a problem of excessive processing costs.

[0007] The present invention aims to provide a press machine that can reduce or eliminate crowning in a non-traditional manner, without significantly increasing the complexity or cost.

[0008] The present application discloses the following invention. <Configuration 1> A press machine that processes a workpiece between an upper die and a lower die placed on an adjustment table, wherein the adjustment table includes: a control rod extending in the width direction and having a plurality of drive pins arranged along the width direction; a rod driver that drives the control rod in the width direction; and a plurality of adjustment blocks arranged along the width direction, wherein each of the adjustment blocks includes: a first tapered plate that extends at a predetermined inclination angle with respect to the width direction and has a first tapered surface and a slot that guides the drive pin; and a second tapered plate that has a second tapered surface that faces the first tapered surface and is complementary to the first tapered surface, wherein the inclination angle of the slot of at least one of the adjustment blocks is different from the inclination angle of the slot of at least one other of the adjustment blocks. <Configuration 2> The press machine of Configuration 1, wherein the inclination angle of the slot of the adjustment block located at the center in the width direction is greater than the inclination angles of the slots of the adjustment blocks located at both ends in the width direction. <Configuration 3> The press machine according to Configuration 1, wherein the adjustment table has a front-rear position adjustment means for adjusting the position of the second tapered plate in the front-rear direction.

[0009] 1 shows a press machine 1 according to an embodiment of the present invention. It shows a side cross-sectional view of the press machine 1. It shows an adjustment table 40. (a) is an overall perspective view. (b) is the adjustment table 40 with a portion of the first tapered plate 50 and the second tapered plate 51 removed. (c) is an enlarged view of the rod drive unit 45. It shows the adjustment table 40. (a) is a plan view of the first tapered plate 50. (b) is a plan view of the second tapered plate 51. (c) is a cross-sectional view of the adjustment table 40 at the A-A position in (a) and (b). It shows a conventional press machine 101. It shows another conventional press machine 201.

[0010] 1 and 2 show a press machine 1 according to one embodiment of the present invention. The press machine 1 includes left and right side frames 10, an upper table (first table) 20 attached to the front of the side frames 10 so as to be movable up and down, and a lower table (second table) 30 fixed to the front of the side frames 10. An upper die 22 can be attached to the lower end of the upper table 20 via a die holder 21, and a die holder 31 and an upper die 32 can be attached to the upper end of the lower table 30 via an adjustment table 40. The die holders 21 and 31 may be omitted, and the dies 22 and 32 may be attached directly to the upper table 20 and / or the adjustment table 40. In this specification, the extension direction of the lower table 30 (the X direction in FIG. 1 ) is referred to as the width direction, and the direction perpendicular thereto (the Y direction in FIG. 2 ) is referred to as the front-rear direction.

[0011] The upper table 20 moves up and down by the driving force of the driving means, and bends the workpiece by clamping it between the upper and lower dies 22, 32 attached to the upper and lower die units 21, 31. In the example of FIG. 2 , the driving means includes a driving source 11a such as a hydraulic cylinder or a servo motor, a drive shaft 11b of the driving source 11a, and a connecting member 11e that connects a force point 11c on the drive shaft 11b to a point of application 11d at the top end of the upper table 20. The upper table 20 is driven up and down by rotating the connecting member 11e around a fulcrum 11f. The driving source 11a can be of any type, such as a hydraulic cylinder or a servo motor. While this example shows a press machine 1 with a movable upper table 20, the present invention is also applicable to a press machine with a movable lower table 30.

[0012] 3 and 4 show the details of the adjustment table 40. The adjustment table 40 has a plurality of adjustment blocks 42 arranged in the width direction.１ , 42 ２ ...42 ｎ (Adjustment block 42 １ , 42 ２ ...42 ｎ The actuator includes a plurality of adjustment blocks 42 (sometimes collectively referred to as adjustment blocks 42), control rods 43 extending in the width direction and arranged below the plurality of adjustment blocks 42, and a rod driver 45 for driving the control rods 43. The adjustment blocks 42 are preferably arranged at regular intervals, and the dimensions and external shapes of the adjustment blocks 42 are preferably the same, although these may be changed as appropriate. To prevent the control rods 43 from bending / curving, bases 43a and 43b extending in the width direction are preferably arranged on both sides of the control rods 43 with a gap between them, and the control rods 43 are allowed to move in the gap between the bases 43a and 43b.

[0013] As shown in FIGS. 4A to 4C, the adjustment block 42 has a first tapered plate 50 and a second tapered plate 51 stacked one above the other. The first tapered plate 50 has a first tapered surface 50a on its upper surface that is inclined at a predetermined angle. The second tapered plate 51 has a second tapered surface 51a on its lower surface that is inclined at a predetermined angle. The first tapered surface 50a and the second tapered surface 51a have complementary shapes / slope. For example, the first tapered surface 50a may have a downward slope toward the rear, and the second tapered surface 51a may have an upward slope toward the rear. The first and second tapered plates 50, 51 are stacked with the first and second tapered surfaces 50a, 51a facing each other / contacting each other.

[0014] 4( a) and 4(c), the first tapered plate 50 of the adjustment block 42 has slots 50b extending at a predetermined inclination angle α with respect to the width direction (X). The inclination angle α of the slots 50b of each adjustment block 42 is set individually, and the inclination angle of the slots 50b of at least one adjustment block 42 is different from the inclination angle of the slots 50b of at least one other adjustment block 42. Preferably, the inclination angle of the slots 50b of the adjustment block 42 closer to the center in the width direction is greater, and the inclination angle of the slots 50b of the adjustment block 42 closer to both ends in the width direction is smaller. The first tapered plate 50 preferably further has guides 50c extending in the front-rear direction and guide pins 50d standing from the top surface of the first tapered plate 50.

[0015] As shown in Fig. 3(c), the control rod 43 is connected at its base end to a rod driving unit 45 having a motor 45a, a rotary belt 45b, a ball screw 45c, etc., and the control rod 43 moves back and forth in the width direction by driving the rod driving unit 45. As shown in Fig. 3(b), the control rod 43 is connected to a plurality of driving pins 44 inserted into slots 50b of each of the first tapered plates 50 arranged in the width direction. １ , 44 ２ ...44 ｎ (In FIG. 3(b), the drive pin 44 １ and 44 ２ Only the drive pin 44 is shown. １ , 44 ２ ...44 ｎ The arrangement interval of the adjustment block 42 １ , 42 ２ ...42 ｎ It is preferable that it is the same as above, but it can be changed as appropriate.

[0016] As shown in Fig. 4, the base 43a has a plurality of guide pins 46 arranged at predetermined intervals in the width direction, and the guide pins 46 are inserted into and guided by the guides 50c of each first tapered plate 50, thereby restricting movement of the first tapered plate 50 in directions other than the front-rear direction. １ , 42 ２ ...42 ｎ Although the figure shows a case where the guide 50c is provided only on the left side of the first tapered plate 50, it is also possible to provide a similar guide 50c on the right side of the first tapered plate 50 to guide a guide pin erected on the base 43b.

[0017] 4(b) and (c), the second tapered plate 51 further has screw holes 51b extending in the front-rear direction, and the second tapered plate 51 can be moved in the front-rear direction by operating the operation bolts 47 extending in the front-rear direction and arranged at predetermined intervals in the width direction of the front wall 41a (for example, by rotating the operation bolts 47 with a hexagonal wrench or the like to move the operation bolts 47 in the front-rear direction). １ , 42 ２ ...42ｎ The second tapered plate 51 has a guide hole 51c extending in the front-rear direction that engages with a guide pin 50d embedded in the first tapered plate 50, and the guide pin 50d is guided by the guide hole 51c, thereby restricting movement of the second tapered plate 51 in directions other than the front-rear direction.

[0018] In the press machine 1, the control rod 43 is moved in the width direction by driving the rod driving unit 45, and the first tapered plate 50 moves in the front-rear direction in accordance with the guide of the drive pin 44 and the slot 50b. １ , 42 ２ ...42 ｎ The height of the first tapered plate 50 can be changed. Because the amount of movement of each first tapered plate 50 in the front-to-rear direction depends on the inclination angle α of the slot 50b of each first tapered plate 50, the widthwise profile of the height of the adjustment table 40 can be adjusted as desired by adjusting the inclination angle α of the slot 50b of each first tapered plate 50, thereby making it possible to correct crowning in the widthwise direction of the lower table 30. For example, by increasing the inclination angle α of the slot 50b of the adjustment block 42 at the center in the widthwise direction and gradually decreasing the inclination angle α of the slot 50b of the adjustment blocks 42 on both widthwise ends, it is possible to correct a concave crowning C1 with a concave center as shown in FIG. 5.

[0019] Furthermore, in the press machine 1, the second tapered plates 51 are individually moved back and forth by operating the operation bolts 47, and thereby the adjustment blocks 42 １ , 42 ２ ...42 ｎ Therefore, after roughly correcting the crowning with the control rod 43, it is possible to fine-tune the crowning of the lower table 30 by operating each operating bolt 47.

[0020] The dimensions, shapes, arrangements, numbers, materials, etc. of the press machine 1 and its elements described in the above embodiment are merely examples, and other embodiments are also possible.

[0021] 1... Press machine 10... Side frame 11a... Drive source 11b... Drive shaft 11d... Point of action 11f... Support point 11c... Point of force 11e... Connecting member 20... Upper table 21... Die holder 22... Upper die 30... Lower table 31... Die holder 32... Lower die 40... Adjustment table 41a... Front wall 41b... Rear wall 42 (42 １ , 42 ２ ...42 ｎ ) Adjustment block 43a, 43b Base 43 Control rod 44 (44 １ , 44 ２ ...44 ｎ )...Drive pin 45...Rod drive unit 45a...Motor 45b...Rotating belt 45c...Ball screw 46...Guide pin 47...Operating bolt 50...First tapered plate 50a...First tapered surface 50b...Slot 50c...Guide 50d...Guide pin 51...Second tapered plate 51a...Second tapered surface 51b...Screw hole 51c...Guide hole α...Inclination angle

Claims

1. A press machine which processes a workpiece between an upper die and a lower die placed on an adjustment table, wherein the adjustment table has: a control rod extending in the width direction and having a plurality of drive pins arranged along the width direction; a rod drive unit which drives the control rod in the width direction; and a plurality of adjustment blocks arranged along the width direction, wherein each of the adjustment blocks has: a first tapered plate which extends at a predetermined inclination angle with respect to the width direction and has a first tapered surface and a slot which guides the drive pin; and a second tapered plate which has a second tapered surface which faces the first tapered surface and is complementary to the first tapered surface, wherein the inclination angle of the slot of at least one of the adjustment blocks is different from the inclination angle of the slot of at least one other of the adjustment blocks.

2. A press machine according to claim 1, wherein the inclination angle of the slot of the adjustment block located in the center in the width direction is greater than the inclination angle of the slot of the adjustment block located at both ends in the width direction.

3. A press machine according to claim 1, wherein said adjustment table has a front-rear position adjustment means for adjusting the front-rear position of said second taper plate.

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