JP7846904B2 - Press machine - Google Patents

Description

Applicable to Article 30, Paragraph 2 of the Patent Law. Press equipment was unveiled at MF-TOKYO 2023 (Tokyo Big Sight) on July 12, 2023.

This invention relates to press machines such as panel benders and press brakes, and more specifically, to press machines capable of correcting and remedying crowning that occurs on the table during bending.

Figure 5 shows a conventional press machine 101. The press machine 101 comprises a side frame 110, an upper table 120 that holds the upper die 122, a lower table 130 that holds the lower die 132, and a table driving means 111, such as a servo motor, fixed to the side frame 110. The upper table 120 is lowered by the drive shaft 112 of the table driving means 111, thereby clamping and bending a workpiece placed between the upper and lower dies 122 and 132. The applied pressure at this time causes concave deflection (crowning), indicated by the dashed lines C1 and C2, in the upper and lower tables 120 and 130, resulting in a decrease in the processing accuracy of the workpiece. This problem is particularly pronounced when the width dimension of the workpiece or the upper and lower tables 120 and 130 is large, or when the applied pressure is high.

As solutions to the above problem, for example, Patent Documents 1 and 2 are known. Patent Document 1 reduces crowning by using the biasing force of multiple deflection-compensating cylinders positioned at the midpoint of the width direction of the lower table. Patent Document 2 reduces crowning by changing the elastic force of the upper and lower tables in the width direction using multiple elastic devices embedded at the midpoint of the width direction of the upper and lower tables.

Another known countermeasure against crowning is the press machine 201 shown in Figure 6. In the press machine 201, the lower table 230 is composed of multiple tables 231-233 stacked front to back, and these are connected by a connecting pin 240 near the center, thereby reducing crowning of the middle table 231.

Japanese Patent Application Publication No. 5-329549 Japanese Patent Publication No. 2004-136366

However, the press machine described in Patent Document 1 suffers from excessive cost increases due to the addition of deflection compensation cylinders. The press machine described in Patent Document 2 has a complex and precise elastic mechanism that is prone to failure, and also has limitations in its load-bearing capacity, making it unsuitable for press machines with high pressing forces. The method shown in Figure 6 requires a number of connecting pins 240 (approximately 2 to 8) corresponding to the width of the press machine 201. However, this requires forming through-holes for each connecting pin 240 in each table 231 to 233 with extremely high positional accuracy, resulting in excessive processing costs.

The objective of this invention is to reduce or eliminate crowning in a manner different from conventional methods. In one embodiment, the objective is to provide a press machine capable of correcting crowning without significantly increasing complexity or cost.

The following invention is disclosed in this application.
<Structure 1>
A press machine that processes a workpiece between an upper die and a lower die placed on an adjustment table,
The aforementioned adjustment stand is
A control rod extending in the width direction having multiple drive pins arranged along the width direction,
A rod drive unit that drives the control rod in the width direction,
Multiple adjustment blocks arranged along the width direction,
It has,
Each of the aforementioned adjustment blocks is,
A first tapered surface and a first tapered plate having a slot that extends at a predetermined inclination angle with respect to the width direction and guides the drive pin,
A second tapered plate having a second tapered surface complementary to the first tapered surface and facing the first tapered surface,
It has,
A press machine characterized in that the inclination angle of the slot of at least one of the adjustment blocks differs from the inclination angle of the slot of another at least one of the adjustment blocks.
<Structure 2>
A press machine according to configuration 1, characterized in that 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 slots of the adjustment blocks located at both ends in the width direction.
<Structure 3>
The press machine according to configuration 1 is characterized in that the adjustment table has a front-to-back position adjustment means for adjusting the front-to-back position of the second tapered plate.

This shows a press machine 1 according to one embodiment of the present invention. A side cross-sectional view of press machine 1 is shown. The adjustment stand 40 is shown. (a) is an overall perspective view. (b) is the adjustment stand 40 with some of the first tapered plate 50 and second tapered plate 51 removed. (c) is an enlarged view of the rod drive unit 45. The adjustment stand 40 is shown. (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 stand 40 at position A-A in (a) and (b). A conventional press machine 101 is shown. Another conventional press machine 201 is shown.

Figures 1 and 2 show a press machine 1 according to one embodiment of the present invention. The press machine 1 comprises left and right side frames 10, an upper table (first table) 20 mounted on the front of the side frames 10 so as to be vertically movable, 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 directly attached to the upper table 20 and/or the adjustment table 40. In this specification, the extending direction of the lower table 30 (the X direction in Figure 1) is referred to as the width direction, and the direction perpendicular to it (the Y direction in Figure 2) is referred to as the front-to-back direction.

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

Figures 3 and 4 show details of the adjustment stand 40. The adjustment stand 40 has a plurality of adjustment blocks ₄₂₁ , ₄₂₂ ... _42n (sometimes the adjustment blocks ₄₂₁ , ₄₂₂ ... _42n are collectively referred to as adjustment blocks 42) arranged in the width direction, a control rod 43 extending in the width direction positioned below the plurality of adjustment blocks 42, and a rod drive unit 45 that drives the control rod 43. The spacing between each adjustment block 42 is preferably constant, and the dimensions and external shape of each adjustment block 42 are preferably the same, but these may be changed as appropriate. To prevent bending/bending of the control rod 43, bases 43a and 43b extending in the width direction are placed on both sides of the control rod 43 with a gap between them, so that the control rod 43 can move in the gap between the bases 43a and 43b.

As shown in Figures 4(a) to 4(c), the adjustment block 42 has a first tapered plate 50 and a second tapered plate 51 stacked vertically. The first tapered plate 50 has a first tapered surface 50a inclined at a predetermined angle on its upper surface. The second tapered plate 51 has a second tapered surface 51a inclined at a predetermined angle on its lower surface. The first tapered surface 50a and the second tapered surface 51a have complementary shapes/inclinations. For example, the first tapered surface 50a may have an inclination that slopes downward toward the rear, and the second tapered surface 51a may have an inclination that slopes upward toward the rear. The first and second tapered plates 50 and 51 are stacked with their first and second tapered surfaces 50a and 51a facing/contacting each other.

As shown in Figures 4(a) and 4(c), the first tapered plate 50 of the adjustment block 42 has a slot 50b that extends with respect to the width direction (X) at a predetermined inclination angle α. The inclination angle α of the slot 50b of each adjustment block 42 is set individually, and the inclination angle of the slot 50b of at least one adjustment block 42 differs from the inclination angle of the slot 50b of at least one other adjustment block 42. Preferably, the inclination angle is larger for the slot 50b of the adjustment block 42 closer to the center in the width direction, and smaller for the slot 50b of the adjustment blocks 42 closer to both ends in the width direction. The first tapered plate 50 may further have a guide 50c extending in the front-rear direction and a guide pin 50d rising from the upper surface of the first tapered plate 50.

As shown in Figure 3(c), the control rod 43 is connected at its base end to a rod drive unit 45 which has a motor 45a, a rotating belt 45b, a ball screw 45c, etc., and the control rod 43 moves back and forth in the width direction by the drive of the rod drive unit 45. As shown in Figure 3(b), the control rod 43 has a plurality of drive pins ₄₄₁ , ₄₄₂ ... _44n (only drive pins ₄₄₁ and ₄₄₂ are shown in Figure 3(b)) which are inserted into slots 50b of each first tapered plate 50 arranged in the width direction. The spacing between the drive pins ₄₄₁ , ₄₄₂ ... _44n should be the same as that _{of the adjustment blocks 421, 422...42n , but} it can be changed as appropriate.

As shown in Figure 4, the base 43a has a plurality of guide pins 46 arranged in the width direction at predetermined intervals, and the guide pins 46 are inserted into the guides 50c of each first tapered plate 50 and guided, thereby restricting the movement of the first tapered plate 50 in directions other than the front-to-back direction. The spacing of the guide pins 46 should be the same as that of the adjustment blocks ₄₂₁ , ₄₂₂ ... _42n , but it can be changed as appropriate. The figure shows a case where the guide 50c is only on the left side of the first tapered plate 50, but it is also possible to provide a similar guide 50c on the right side of the first tapered plate 50 and guide the guide pin erected on the base 43b.

As shown in Figures 4(b) and 4(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 operating bolts 47 that extend in the front-rear direction and are arranged at predetermined intervals in the width direction of the front wall 41a (for example, by rotating the operating bolts 47 using a hex wrench or the like to move the operating bolts 47 in the front-rear direction). The arrangement interval of the operating bolts 47 should be the same as that of the adjustment blocks ₄₂₁ , ₄₂₂ ... _42n , but can be changed as appropriate. The second tapered plate 51 has guide holes 51c that extend in the front-rear direction and engage with guide pins 50d planted in the first tapered plate 50, and the movement of the second tapered plate 51 in directions other than the front-rear direction is restricted by the guide pins 50d being guided into the guide holes 51c.

In the press machine 1 described above, the control rod 43 is moved in the width direction by the drive of the rod drive unit 45, causing the first tapered plate 50 to move in the front-rear direction according to the guidance of the drive pin 44 and the slot 50b, thereby changing the height of each adjustment block ₄₂₁ , ₄₂₂ ... _42n . Since the amount of front-rear movement of each first tapered plate 50 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 arbitrarily adjusted by adjusting the inclination angle α of the slot 50b of each first tapered plate 50, thereby correcting crowning in the width direction of the lower table 30. For example, by increasing the inclination angle α of the slot 50b of the adjustment block 42 in the width direction and sequentially decreasing the inclination angle α of the slots 50b of the adjustment blocks 42 at both ends in the width direction, it is possible to correct concave crowning C1 with a concave center as shown in Figure 5.

Furthermore, in the press machine 1, each second tapered plate 51 can be individually moved back and forth by operating each operating bolt 47, thereby making it possible to individually adjust the height of each adjustment block ₄₂₁ , ₄₂₂ ... _42n . Therefore, after roughly correcting the crowning with the control rod 43, it is possible to further fine-tune the crowning of the lower table 30 by operating each operating bolt 47.

The dimensions, shape, arrangement, number, materials, etc., of the press machine 1 and its elements described in the above embodiment are illustrative examples, and other configurations are also possible.

1... Press machine 10... Side frame 11a... Drive source 11b... Drive shaft 11d... Point of application 11f... Pivot point 11c... Point of force application 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 (3)

A press machine that processes a workpiece between an upper die and a lower die placed on an adjustment table,
The aforementioned adjustment stand is
A control rod extending in the width direction having multiple drive pins arranged along the width direction,
A rod drive unit that drives the control rod in the width direction,
Multiple adjustment blocks arranged along the width direction,
It has,
Each of the aforementioned adjustment blocks is,
A first tapered surface and a first tapered plate having a slot that extends at a predetermined inclination angle with respect to the width direction and guides the drive pin,
A second tapered plate having a second tapered surface complementary to the first tapered surface and facing the first tapered surface,
It has,
A press machine characterized in that the inclination angle of the slot of at least one of the adjustment blocks differs from the inclination angle of the slot of another at least one of the adjustment blocks. The press machine according to claim 1, characterized in that 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 slots of the adjustment blocks located at both ends in the width direction. The press machine according to claim 1, characterized in that the adjustment table has a front-to-back position adjustment means for adjusting the front-to-back position of the second tapered plate.