JPH0688080B2 - Press brake - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press brake, and more particularly, to a press brake including a rowing device that corrects the deflection of an upper die or a lower die of the press brake. It is about.

[Conventional technology]

Generally, as a press brake for bending a long work such as a long metal material along the longitudinal direction, the left and right lengths of the pressing surface are long and the front and rear widths are extremely short, so it was installed on the left and right rear sides. A pair of side frames is used as a base, and a fixed lower table is provided on the base. BACKGROUND ART Press brakes, which perform press work by vertically moving an upper table by a pressure cylinder such as a hydraulic cylinder provided on both ends of a pair of side frames, have been most known and used since ancient times.

In the above-mentioned type of press brake, characteristics such as tensile strength, yield point, and elastic coefficient of the work appear as so-called drag force that resists during bending. That is, the center of the movable upper table largely bends upward, and similarly, the center of the fixed table also bends downwardly, and the distance between the movable upper table and the fixed table tends to widen toward the center. There is a problem that the processing finish of "is called" boat type.

Many proposals have already been made as a crowning device for solving the above problems. For example, as a typical one, a wedge having different angles is interposed between the die holder and the die, or the wedges have the same angle but are moved to adjust each wedge. There are a configuration in which the pitches of the screws are different, a configuration in which the pitch circle diameters of the chain sprockets attached to the respective screws for moving the wedges are different, or a hydraulic cylinder is used.

[Problems to be solved by the invention]

However, even the typical conventional ones described above have merits and demerits. For example, with a structure in which a plurality of wedges having different angles are adjusted, it is possible to adjust the wedges at one time, but it is difficult to process the wedges. Although the angles of multiple wedges are the same, if the pitches of the screws that move each wedge are made different, or if the pitch circle diameter of the chain sprocket provided for each screw is made different, the screw for each wedge is ， It is necessary to drive the sprocket, etc., and it is very difficult to stabilize accuracy such as rattling of the screw and backlash of the sprocket. Also,
Even with hydraulic cylinders, there are still problems with accuracy due to variations in pressure settings, etc.
No satisfactory means have emerged to completely solve the problem.

[Means for Solving the Problem] In view of the conventional problems as described above, according to the present invention, in a press brake, a die base that supports a long die in the left-right direction is mounted on a lower table that is long in the left-right direction so as to be vertically movable. And the lower surface of the upper wedge attached to the lower surface of the die base is inclined in the front-rear direction.
A plurality of lower wedges interposed between the lower surface of the upper wedge and the upper surface of the lower table are arranged at appropriate intervals in the left-right direction and are movable in the front-rear direction. In the vicinity of the part, elastic members whose central part is fixed to the lower table are provided symmetrically, and both left and right sides of the elastic member are flexibly provided, and follow the above-mentioned curvature of both left and right sides of the elastic member. Each of the lower wedges is configured to move in the front-rear direction.

Further, in the press brake, a die base supporting a die long in the left-right direction is mounted on a lower table long in the left-right direction so as to be vertically movable, and the lower surface of the upper wedge attached to the lower surface of the die base is moved forward and backward. And a plurality of lower wedges interposed between the lower surface of the upper wedge and the upper surface of the lower table at appropriate intervals in the left-right direction and movably in the front-rear direction. A plurality of movable supporting members provided on the lower table so as to be movable in the left-right direction in the vicinity of the center of the lower table in the left-right direction are provided with elastic members supported on both sides in the vicinity of the center in a symmetrical manner. The right and left sides of the elastic member are curved, and the lower wedges move in the front-rear direction following the bending of the left and right sides of the elastic member. .

[Action]

In the above structure, when the right and left side portions of the elastic member are appropriately curved, the displacement amount due to the curvature greatly differs between the central portion and the end portion of the elastic member, so that the lower wedge of the lower elastic member that follows the curvature of the elastic member moves. The amount of movement in the front-rear direction also varies depending on each lower wedge, and the crowning is adjusted according to the bending of the elastic member.

That is, the plurality of lower wedges are adjusted simultaneously according to the bending of the elastic member, and the adjustment is easy.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, hydraulic cylinders 5A and 5B, which are pressurizing cylinders, are attached to the upper portions of both ends of side frames 3A and 3B provided on both left and right rear sides of the press brake 1. The piston rods 7A and 7B of the hydraulic cylinders 5A and 5B are attached to the left and right shoulders 9A and 9B of the upper table 9. Therefore, by activating the hydraulic cylinders 5A and 5B,
The upper table 9 is moved up and down via the piston rods 7A and 7B, and the punch P of the die attached to the lower portion of the upper table 9 is moved up and down.

On the other hand, the lower table 11 is fixed to the side frames 3A and 3B. A plurality of front plates 13 and rear plates 15 are provided in front of and behind the upper part of the lower table 11 as shown in FIGS. 1, 2, 3, 4, 5 and 6. It is attached with bolts 17 and 19 of the book.

On the upper part between the front plate 13 and the rear plate 15, a die base 21 to which a die D of a mold is attached is sandwiched and provided. 1, 2, and 7 of the front plate 13 and the rear plate 15, the die mounting plate 23 is mounted by a plurality of bolts 25 in a plurality of grooves formed at regular intervals along the left-right direction. There is. That is, the height of the die mounting plate 23 is slightly higher than the heights of the front plate 13 and the rear plate 15, and the die D of the die placed on the die base 21 is supported from the front and back. .

Between the front plate 13 and the rear plate 15,
A leaf spring as an elastic member placed on the lower table 11.
The inverted U-shaped movable support members 29A and 29B are arranged at substantially equal intervals from the center line CL in the left-right direction so as to sandwich the central portion 27C of the 27 from above, as shown in FIGS. 3 and 4. is there. The movable support member 29A extending between the rear plate 15 and the central portion 27C of the leaf spring 27 and extending on the lower table 11 with a certain length in the left-right direction from the center line CL,
A guide member 31 for guiding 29B is provided.

Therefore, the guide member 31 is fitted in the groove formed in the lower portion between the rear plate 15 and the central portion 27C of the leaf spring 27 in the movable support members 29A, 29B, and the movable support members 29A, 29B are formed.
Is guided by the guide member 31 and moved in the left-right direction.

In FIGS. 3 and 4, an L-shaped bracket 33 is attached by a plurality of bolts 35 to the rear end of the rear plate 15 on the left side of the center line CL. bracket
A drive motor 37 for moving the movable support members 29A, 29B in the left-right direction is attached to the 33. One pulley 41 is attached to the output shaft 39 of the drive motor 37.

The movable support members 29A, 29B are provided with through holes 43A, 43B penetrating in the left-right direction in FIG.
Female threads are engraved on the inner circumference of each of 3A and 43B. The right screw 45A is screwed into the female screw of the through hole 43A, the left screw 45B is screwed into the female screw of the through hole 43B, and the right screw 45A and the left screw 45B.
And are integrated at the center line CL to form the screw 45. One end portion (the left side portion in FIG. 3) of the screw 45 is a supporting member 47A, 47B and a plurality of bolts 49 are used for the lower table 1.
It is concluded in 1. The other pulley 51 is attached to one end (the left side in FIG. 3) of the screw 45, and a belt 53 such as a timing belt is wound around the other pulley 51 and the one pulley 41.

With the above configuration, when the drive motor 37 is driven, the output shaft 3
The screw 45 is rotated via 9, the pulley 41, the belt 53 and the pulley 51. When the screw 45 is rotated, the right screw 45 of the screw 45
Since A is screwed to the movable support member 29A and the left screw 45B of the screw 45 is screwed to the movable support member 29A, rotation of the right screw 45A and the left screw 45B of the screw 45 causes the movable support members 29A and 29B to be centered.
They will approach each other or move away from each other around CL. Therefore, when the movable support members 29A and 29B approach each other or move away from each other around the center line CL, the fulcrum of the central portion 27C of the leaf spring 27 can be adjusted in the left-right direction in FIG. This leaf spring 27
Since the fulcrum of the central portion 27C can be adjusted, the bending of the left and right side portions 27S of the leaf spring 27 can be adjusted.

Both side portions 27S of the leaf spring 27 are movable supporting members near the central portion 27C.
29A and 29B are provided as movable fulcrums so that they can be bent back and forth, that is, in the thickness direction of the table, and the amount of bending can be adjusted. More specifically, as shown in FIG. 2, FIG. 3 and FIG. 5, one of the ball joints 55 is attached to the end faces of both side portions 27S of the leaf spring 27. The other side of the ball joint 55 is screwed to the stroke nut 57 of the driven portion of the drive source provided at the left and right ends of the rear plate 15. The stroke nut 71 is fitted in the ball spline shaft 59 and is screwed to the T-shaped shaft 61. An upper portion of the shaft 61 is fitted in a cylindrical member 63, a sprocket 65 is fitted in the cylindrical member 63, and is fastened with a screw 67. The cylindrical member 63 is supported by the holder member 71 via a plurality of bearings 69. The screw 73 attached to the holder member 71 serves to prevent the ball spline shaft 59 from rotating.

With the above-mentioned configuration, the sprocket 65 is driven by the drive unit described later.
When is rotated, the other side of the ball joint 55 moves up and down in FIG. 3 via the shaft 61, the stroke nut 43, and the ball spline shaft 59, so that both side portions 27S of the leaf spring 27 move forward and backward (in FIG. 3). The amount of bending up and down will be adjusted.

In order to bend both sides 27S of the leaf spring 27 back and forth and to adjust the amount of bending, the sprockets 65 attached to both ends of the rear plate 15 via the ball joint 55 are rotated.

More specifically, as shown in FIG. 1, sprockets 65 are attached to both ends of the rear plate, and an idler sprocket 75 is attached to the lower left portion of the lower table 11. A drive unit 77 for rotating the sprocket 65 is provided on the lower right side of the lower table 11.
The drive unit 77 includes a control motor 79 such as an inverter motor.
Is attached to the output shaft of the control motor 79 and the pulley 81
Is installed. On the upper portion of the control motor 79, the other pulley 85 is attached to the lower table 11 via the shaft 83.
A belt 87 such as a timing belt is wound around one pulley 81 and the other pulley 85. A sprocket 89 is attached to the shaft 83. With this sprocket 89,
A chain 91 is hooked around sprockets 65 attached to both upper ends of the rear plate 15 and an idler sprocket 75 attached to a lower left portion of the lower table 11. Furthermore, in the lower center part of the lower table 11, there is a chain 91
A tension pulley 93 for adjusting the tension of is attached.

With the above configuration, by driving the control motor 79, the shaft 83 is rotated via the pulley 81, the belt 87, and the pulley 85. The rotation of the shaft 83 causes the sprocket 65 to rotate via the sprocket 89 and the chain 91. When the sprocket 65 is rotated, as described above, the two end portions 27 of the leaf spring 27 are inserted through the ball joint 55.
S will bend back and forth.

The amount of bending of both sides 27S of the leaf spring 27 depends on the control motor 79
Is performed by controlling the rotation of the. Control motor 79
Has an encoder (not shown) attached,
The rotation of the control motor 79 will be controlled.

In this embodiment, the both side portions 27S of the leaf spring 27 are simultaneously bent as described above, but the both side portions 27S of the leaf spring 27 may be individually corrected and controlled.

Referring to FIG. 2, FIG. 3, FIG. 5, and FIG. 6, in the upper longitudinal direction of the lower table 11 mounted in a sandwich shape between the front plate 13 and the rear plate 15, the leaf spring 27 Lower wedges 95 whose upper surfaces are inclined forward and backward are provided at appropriate intervals at appropriate positions (for example, three places) across both side portions 27S. As shown in FIG. 6, each lower wedge 95 has a front plate 13 in a groove 97 formed therein.
The pin 99 is inserted from the side, and the pin 99 is inserted in the linear bearing 101 mounted in the groove 97. Therefore, each lower wedge 95 is supported by the linear bearing 101 in a state where no load is applied, the power for operation is also small, and more accurate positioning can be performed.

Further, the set screw 103 is inserted into holes formed in the front and rear of the lower portion of each lower wedge 95. The set screw 103 holds the front and rear of both side portions 27S of the leaf spring 27. Both side portions 27S of the leaf spring 27 and the lower table 1
A slight gap is provided between the side table 27 and the first table 1 so that both side portions 27S of the leaf spring 27 can be smoothly moved with respect to the lower table 11 during positioning.

With the above configuration, both side portions 27S of the leaf spring 27 are bent back and forth with respect to the central portion 27C, so that the lower wedge 95 is smoothly moved back and forth.

As shown in FIG. 2, FIG. 5 and FIG. 6, upper wedges 105 are provided on the upper surfaces of the lower wedges 95 so as to engage with the inclined surfaces inclined forward and backward with a slight clearance. Each upper wedge 10
5 is fastened to the die base 21 by a plurality of bolts 107.

Therefore, as the lower wedge 95 moves back and forth, the die base 21 obtains a force for moving the upper wedge 105 up and down.

As can be understood from the above description, both side portions 27 of the leaf spring 27 are
By bending both ends of S back and forth, each lower wedge 95 moves back and forth according to the amount of bending of the leaf spring 27. Based on the amount of front and rear movement of each lower wedge 95, the die base 21
The force of each part of moving up and down is obtained. Leaf spring 27
The bending amount of the both side portions 27S is such that the bending amount increases toward the both ends. As described above, since the leaf spring 27 is flexibly set in advance in a shape proportional to the shapes of the upper table 9 and the lower table 11, the crowning can be corrected more accurately.

As shown in FIGS. 2 and 7, there is a spring support between the lower wedge 95 on the central side and the lower wedge 95 on the side of the lower table 11 in the longitudinal direction. 109
There is a plurality of, for example, two bolts 111 for the lower table 1
It is concluded in 1. The spring receiver 109 has a ridge 113
The lifter spring 115 is attached to the protruding pillar 113.
And is urged between the die base 21 and the lower table 11.

With the above configuration, the die base 21 on which the die D is placed is slightly floated by the lifter spring 115, and does not change even if the abutting point is crowned.

Of the lower wedges 95 (for example, three), the lower wedge in the middle
Eccentric shafts 117 are provided from the outside of the front plate 13 and the rear plate 15 between the 95 and the lateral lower wedge 95 toward the inside as shown in FIGS. 2 and 8.
The eccentric shaft 117 is for adjusting the up and down of the front plate 13 and the rear plate 15 in advance.

〔effect〕

As will be understood from the above description of the embodiments, in short, the present invention provides a die base (21) for supporting a die (D) that is long in the left-right direction on a lower table (11) that is long in the left-right direction in a press brake. It is a press brake which is vertically movable, and the lower surface of the upper wedge (105) attached to the lower surface of the die base (21) is provided with an inclination in the front-rear direction. Table (1
A plurality of lower wedges (95) interposed between the lower table (11) and the upper surface of (1) are provided at appropriate intervals in the left-right direction, and are movable in the front-rear direction. An elastic member (27) whose central portion is fixed to the lower table (11) in the vicinity is provided symmetrically,
The left and right side portions (27S) of the elastic member (27) are provided so as to be curved, and the lower wedges (95) are moved in the front-rear direction by following the bending of the left and right side portions (27S) of the elastic member (27). It is configured to move.

In the press brake, a die base (21) that supports a die (D) that is long in the left-right direction is vertically movably mounted on a lower table (11) that is long in the left-right direction to form a press brake. The lower surface of the upper wedge (105) attached to the lower surface of the lower wedge (105) is inclined in the front-rear direction, and a plurality of lower wedges interposed between the lower surface of the upper wedge (105) and the upper surface of the lower table (11). (95) are arranged at appropriate intervals in the left-right direction and are movable in the front-rear direction so that they can move in the left-right direction to the lower table (11) near the center of the lower table (11) in the left-right direction. The plurality of movable support members (29A, 29B) provided are provided with elastic members (27) supported on both sides in the vicinity of the central portion in a symmetrical manner, and the left and right side portions (27S) of the elastic members (27) are curved. Provided freely, this elastic member (27) The left and right side portions (27
The lower wedges (95) move in the front-rear direction following the curvature of (S).

Therefore, according to the present invention, the left and right side portions 27 of the elastic member 27 are
When S is curved appropriately, the amount of displacement due to the curvature is significantly different near the center and near the ends, and the amount of movement of each lower wedge that follows this curvature is different, so it is adjusted up and down according to each lower wedge. The vertical curvature of the die base is different, and the crowning will be adjusted.

That is, according to the present invention, the plurality of lower wedges are simultaneously adjusted in accordance with the bending of the elastic member, so that the adjustment is easy.

Further, according to the present invention, the vicinity of the central portion of the elastic member 27 is supported by the movable supporting member provided so as to be movable in the left-right direction, and bends around the movable supporting member as a fulcrum. Even when the displacement amount of the end portion of 27S is kept constant, the bending state of the elastic member 27 is different due to the change of the position of the movable support member, and the crowning adjustment mode is also different.

In other words, by adjusting the position of the movable support member, the bending mode of the elastic member can be adjusted to change the mode of crowning adjustment, and the crowning adjustment corresponding to the processing of various workpieces can be easily performed. It is possible.

[Brief description of drawings]

FIG. 1 is a front view of a press brake to which the present invention is applied. FIG. 2 is an enlarged half sectional view of the right side portion centering on the center line CL of the table in FIG. FIG. 3 is a sectional view taken along line III-III in FIG. FIG. 4 is a sectional view taken along the line IV-IV in FIG. FIG. 5 is a sectional view taken along line VV in FIG. FIG. 6 is a sectional view taken along line VI-VI in FIG. FIG. 7 is a sectional view taken along the line VII-VII in FIG. FIG. 8 is a sectional view taken along the line VIII-VIII in FIG. [Explanation of the symbols showing the main parts of the drawing] 1 …… Press brake 9 …… Upper table 11 …… Lower table 13 …… Front plate 15 …… Rear plate 21 …… Die base 27 …… Elastic member (leaf spring) 27C ...... Center part 27S ...... Both sides 29A, 29B ...... Movable support member 95 ...... Lower wedge 105 ...... Upper wedge D ...... Die

Claims (2)

[Claims] 1. A press brake in which a die base (21) for supporting a die (D) that is long in the left-right direction is vertically movably mounted on a lower table (11) that is long in the left-right direction. The lower surface of the upper wedge (105) attached to the lower surface of the die base (21) is provided so as to be inclined in the front-back direction, and the lower surface of the upper wedge (105) and the lower table (1
A plurality of lower wedges (95) interposed between the lower table (11) and the upper surface of (1) are provided at appropriate intervals in the left-right direction, and are movable in the front-rear direction. An elastic member (27) whose central portion is fixed to the lower table (11) in the vicinity is provided symmetrically,
The left and right side portions (27S) of the elastic member (27) are provided so as to be curved, and the lower wedges (95) are moved in the front-rear direction by following the bending of the left and right side portions (27S) of the elastic member (27). A press brake characterized by being configured to move. 2. A press brake in which a die base (21) for supporting a die (D) which is long in the left-right direction is vertically movably mounted on a lower table (11) which is long in the left-right direction in the press brake. The lower surface of the upper wedge (105) attached to the lower surface of the die base (21) is provided so as to be inclined in the front-back direction, and the lower surface of the upper wedge (105) and the lower table (1
A plurality of lower wedges (95) interposed between the lower table (11) and the upper surface of (1) are provided at appropriate intervals in the left-right direction, and are movable in the front-rear direction. In the vicinity of the lower table (11), a plurality of movable supporting members (29A, 29B) movably provided in the left-right direction are provided with elastic members (27) supported on both sides in the vicinity of the central portion in a symmetrical manner. The left and right side portions (27S) of the elastic member (27) are flexibly provided, and the lower wedges (9) follow the curvature of the left and right side portions (27S) of the elastic member (27).
A press brake characterized in that 5) is configured to move in the front-rear direction.