JPH06190456A - Bending device for metallic rod and the like - Google Patents

Abstract

PURPOSE:To perform in one process the bending of a work in which the quantity of spring back is estimated and also to contrive the saving of space for installing machines. CONSTITUTION:A punch 11 having punching faces 11b, 11c inclined inward by an estimated amt. of the spring back is provided. On a vertically moving frame 17, a pair of rotary dies 18, 18a is provided rotatably by means of rotary shafts 19, 19a. In the pair of rotary dies 18, 18a, first abutting parts 20, 20a, shift cam faces 21, 21a, second abutting parts 22, 22a are formed. Work set tables 12, 12a are provided on the left and right of the punch 11. By lowering the pair of rotary dies 18, 18a which are in open state, the work 1 is bent by the first abutting parts 20, 20a; and by bringing the second abutting parts 22, 22a into contact with the work 1, the rotary dies 18, 18a are closed and rotated to bend the work 1 up to the punching faces 11b, 11c of the punch 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending machine for metal rods or plates.

[0002]

2. Description of the Related Art Conventionally, there is a product in which a straight round bar is bent by 180 ° as shown in FIG. Then, in the case where a small tolerance (for example, +0, -0.5 mm) of the width A of the parallel straight portions 1a, 1b is required,
180 ° in anticipation of the amount of springback during bending
It is necessary to fold it to a larger size than that.

As such a bending method, there is conventionally a method of first performing one bending as shown in FIG. 3 and then performing the shifting forming using a shifting cam as shown in FIG. That is, as shown in FIG. 3 (a), the work 1 is placed on the fixed mold 2 having the mold groove 2 a formed therein, and then, FIG.
3, the punch 3 is lowered to place the work 1 thereon, and then the punch 3 is lowered to move the work 1 as shown in FIG. 3B.
Bend 180 ° and make one bend. However, when the punch 3 is released from the mold and the work 1 is taken out after the bending, the spring back causes the work 1 to be slightly opened.

Therefore, in the next step, the work 1 bent as described above is placed on the punch 4 having a downwardly reduced size in the shift molding machine as shown in FIG. As shown in (b), the upper dies 5 and 5 are lowered, and the taper portions bring the moving cams 6 and 6 to the work side to move the work 1.
Bend inward more than 180 ° in consideration of the amount of spring back.

[0005]

According to the conventional bending method described above, two steps are required and the work efficiency is low. Moreover,
In addition to requiring two types of processing machines, in the case of the shift molding machine, the shift cam moves in the lateral direction and the taper portion is made gentle to ensure smooth movement.
There is a problem that the machine width becomes large and the machine device space becomes large.

[0006] Therefore, the present invention proposes a bending machine in which bending considering the amount of spring back can be performed in one step and the machine installation space is narrower than before, and an object thereof is to solve the above problems. To do.

[0007]

In order to solve the above-mentioned problems, the present invention has mold surfaces (11b), (11c) inclined inwardly by the amount of springback on the left and right side surfaces.
And a work set table (12), (12a) for temporarily holding the work (1) in the left-right direction above the punch (11), and the punch (11) is arranged on the left and right of the punch (11). A pair of rotary dies (18), (18a)
And the lifting frame (17), the lifting frame (17) is
The rotary shaft (1
9) and (19a) are provided with the pair of rotary dies (18) and (18a) rotatably so as to open and close in the direction of the punch (11).
8) and (18a), in the open state, have first contact portions (20) and (20a) formed at the lower end left and right from the punch (11), and from the first contact portion to the inside. Shifting cam surfaces (21) and (21a) that are inclined upwards,
The second contact portions (22) and (22a) formed at the upper end of the approach cam surface and directly above the punch (11) are provided, and the pair of rotary dies (18) and (18a) further include: It is characterized in that an urging means for urging this in the opening direction with a predetermined force is provided.

[0008]

Operation: With the elevating frame (17) slightly raised from the state shown in FIG.
2) It is installed between (12a) and horizontally arranged and set on the punch (11).

Next, when the elevating frame (17) is lowered, the pair of rotary dies (18), (18a) are lowered in the open state shown in FIG. 1, and the first contact portions (20), (20a) thereof cause Both sides of the work (1) are bent downward around the punch (11) part.

When the second contact parts (22), (22a) of the pair of rotary dies (18), (18a) contact the work (1) in the punch (11) part, the rotary shaft (19),
Further lowering of (19a) causes the pair of rotary dies (18), (18a) to rotate inward, and the contact cam surfaces (21), (21b) of the rotary dies (18), (21a) punch both sides of the work (1). ) Is pressed against the mold surfaces (11b) and (11c).

Finally, on both sides of the work (1), as shown in FIG. 2, the die surface (11) of the punch (11) is
b), bent to the state of (11c), 1
It is bent extra by the amount of springback than 80 °.

When the elevating frame (17) is raised after the bending process, the operating rods (28), (28a) and the springs (31) provided on the pair of rotary dies (18), (18a),
By the biasing means composed of (31a), the pair of rotary dies (18) and (18a) are opened and returned to the original state by the operation opposite to the above.

[0013]

EXAMPLE Next, an example shown in FIGS. 1 and 2 in which the present invention is applied to bending of a metal round bar will be described.

Reference numeral 10 is a base, and a punch 11 is erected and fixed to the center of the base. The upper end surface 11a of the punch 11 is
Formed in a predetermined semi-curved surface in the left-right direction, the left and right mold surfaces 11
b and 11c are formed on inclined surfaces that are slightly inclined inward from the upper end surface. The inclination angles of the left and right mold surfaces 11b and 11c are set to angles that allow the work to be bent to be bent further inward by the amount of springback.

Reference numerals 12 and 12a denote work set bases arranged on both sides of the punch 11, which are rotatably supported by fixed shafts 13 and 13a by support shafts 14 and 14a, respectively. Work set grooves 15 and 15a are formed on the inner upper surfaces of the work set tables 12 and 12a, and balance weights 16 and 16a are attached to the rear portions thereof.

Reference numeral 17 denotes an elevating frame, which is moved up and down by a hydraulic cylinder device or the like (not shown). 18, 18
a is a pair of rotary dies, which is the center line XX of the punch 11.
Are symmetrically arranged on the left and right, and the rotating shafts 19 and 19a that are fixedly mounted respectively are rotatably connected to and supported by the elevating frame 17.

Both rotary dies 18 and 18a have their rotary shafts 19 and 18a in the normal state before processing (the state of FIG. 1).
The first contact portions 20, 20a are provided immediately below the reference numeral 19a, and the shift cam surfaces 21, 21a are inclined upward and inward from the first contact portions 20, 20a. ，
The second contact portion 22, 22a is located on the upper end surface of 21a and directly above the punch 11 and is bent inward.

The first abutting portions 20, 20a, the shifting cam surfaces 21, 21a, and the second abutting portions 22, 22a are formed in a groove shape into which a work is fitted. Further, in both rotary dies 18 and 18a, the inner end surfaces 23 and 23a of the punches 11 abut each other on the center line XX of the punch 11 so that the normal open state of FIG. 1 is regulated and held. There is.

Reference numeral 24 is a holding frame fixed to the upper part of the elevating frame 17, an upper frame 26 is fixed to the upper part of the holding frame via a side frame 25, and a spring chamber 27 is formed. 28, 28a
Is an actuating rod provided on the holding frame 24 so as to be able to move up and down, and its lower end is rotatably connected to the rotary dies 18, 18a by connecting shafts 29, 29a. The connecting shafts 29, 29a are
It is provided outside the rotary shafts 19 and 19a.

At the upper ends of the operating rods 28 and 28a, the spring receivers 30 and 30a are located inside the spring chamber 27.
Is provided. 31 and 31a are spring receivers 3
A spring interposed between 0 and 30a and the holding frame 24 urges both operating frames 28 and 28a upward.

Reference numerals 32 and 32a denote body projecting blocks fixedly provided on the lower surface of the holding frame 24, and are formed so that the upper ends of the rotary dies 18 and 18a come into contact with each other after the end of the bending of the rotary dies 18 and 18a. There is.

Next, the bending operation will be described. Before the processing operation, the elevating frame 17 is located slightly above the state of FIG. 1, and the pair of rotary dies 18, 18a are also retracted slightly above the state of FIG. In this state, the inner end surfaces 23, 23a of the pair of rotary dies 18, 18a abut each other by the urging force of the springs 31, 31a, and the pair of rotary dies 18, 18a are opened as shown in FIG.

In this state, the linear work 1 to be processed
Is placed and set between both work set bases 12 and 12a.
At this time, the horizontal weight of the work 1 is held by the balance weights 16 and 16a.

Next, the elevating frame 17 is lowered. FIG. 1 shows a state where the first contact portions 20, 20a of the pair of rotary dies 12, 12a are in contact with the upper surface of the work 1. When the elevating frame 17 is further lowered, the pair of rotary dies 18 and 18a are lowered to the open state shown in FIG. 1 by the urging force of the springs 31 and 31a, and the work 1 is moved by the first contact portions 20 and 20a. Pushed down. Therefore, the work 1 is bent at the central portion in contact with the upper end surface 11a of the punch 11, and both side ends thereof are disengaged from the work set tables 12 and 12a.

When the elevating frame 17 is further lowered, the work 1 is further bent, and the pair of rotary dies 18, 18a are in the open state, and the second abutting portions 22, 22a thereof are brought into contact with the work 1 on the punch 11. Abut.

Further, the lifting frame 17 is attached to the springs 31 and 31a.
When it is lowered against the urging force of the pair of rotary dies 18,
Since the second contact portions 22 and 22a of 18a come into contact with the work 1 to stop and the rotary shafts 19 and 19a descend, the rotary die 18 on the left side of the drawing rotates counterclockwise about the rotary shaft 19. , The rotary die 18a on the right side of the drawing is the rotary shaft 19
Rotate clockwise around.

Then, when the work 1 folded by the shifting cam surfaces 21, 21a of the pair of rotary dies 18, 18a comes into contact with the left and right mold surfaces 11b, 11c of the punch 11, the lowering of the elevating frame 17 is stopped. To do. At this time, the upper surfaces of the pair of rotary dies 18 and 18a are brought into contact with the barrel projecting locks 32 and 32a, and the final rotational position thereof is restricted.

Since the left and right mold surfaces 11b and 11c of the punch 11 are inclined as described above, the work 1 is bent more than 180 ° by the amount of springback.

After the above bending process is completed, the elevating frame 17
By raising the pair of rotary dies 18, 18a
Is opened by the urging force of the springs 31 and 31a, and is moved upward to return to the state before processing, and the work set bases 12 and 12a are also balanced weights 16 and 16.
It returns to the horizontal state by a.

By this demolding, the work 1 returns to a state in which both linear portions 1a and 1b thereof are parallel to each other due to the spring back thereof, and the 180 ° bending is completed. And
The work 1 is taken out from the punch 7.

In the above embodiment, the case where the work of the metal round bar is bent is explained. However, in the present invention, the case where the metal plate material is excessively bent by the amount of the springback amount. Of course, it can also be applied to.

[0032]

As described above, according to the present invention, it is possible to perform the bending process of the work in consideration of the springback amount in one step, and the work efficiency can be improved.

Further, since the pair of rotary dies having the shifting cam surfaces are of the type that can be moved vertically and opened and closed, the machine installation space may be narrower than that of the conventional one. Further, since it is not necessary to use two kinds of processing machines as in the conventional case, space saving can be achieved also from this point.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention and showing a state before bending.

FIG. 2 is a vertical cross-sectional view showing a state after the bending process.

FIG. 3 is a longitudinal sectional view showing a first step in a conventional bending work, in which (a) is a state before processing and (b) is a state after processing.

FIG. 4 is a longitudinal sectional view showing a second step in a conventional bending work, in which (a) is a state before processing and (b) is a state after processing.

FIG. 5 is a perspective view showing a work to be bent according to the present invention.

[Explanation of symbols]

 1 Work 11 Punch 11b, 11c Mold surface 12, 12a Work set stand 17 Lifting frame 18, 18a Rotating die 19, 19a Rotating shaft 20, 20a 1st contact part 21, 21a Aligning cam surface 22, 22a 2nd contact part 31, 31a Spring as biasing means

Claims (1)

[Claims] 1. Mold surfaces (11b), (11c) inclined inward by the amount of springback on the left and right sides.
And a work set table (12), (12a) for temporarily holding the work (1) in the left-right direction above the punch (11), and the punch (11) is arranged on the left and right of the punch (11). A pair of rotary dies (18), (18a)
And the lifting frame (17), the lifting frame (17) is
The rotary shaft (1
9) and (19a) are provided with the pair of rotary dies (18) and (18a) rotatably so as to open and close in the direction of the punch (11).
8) and (18a), in the open state, have first contact portions (20) and (20a) formed at the lower end left and right from the punch (11), and from the first contact portion to the inside. Shifting cam surfaces (21) and (21a) that are inclined upwards,
The second contact portions (22) and (22a) formed at the upper end of the approach cam surface and directly above the punch (11) are provided, and the pair of rotary dies (18) and (18a) further include: A bending machine for a metal round bar or the like, which is provided with an urging means for urging this in a direction of opening with a predetermined force.