JPH08108219A - Bending press for sheet metal - Google Patents

Abstract

PURPOSE: To enable forward bending of a sheet metal to such a great extent as the hollow size of an upper frame by putting a blade die under the beak shaped projection of a receiving die and forming the forward and backward bending blades as a pair of front and rear blades. CONSTITUTION: Forming is integrally performed with a forward 25A and backward 25B bending blades formed as a pair of front and rear blades in a metallic die 25. A receiving die 13 and a holding die 17 are protruded inward like a beak of a bird, and forward bending starts with the blade die 25 going under a projecting part 13A. A main link 27 is connected to a main crank mechanism 33 provided in the lower end part of a lower frame 5. The oscillation of the main link 27 is around a pivotally attached pin 31 that moves in relation with a sublink 29, enabling the blade die 25 to be positioned freely. In the case of transfer to backward bending, the center of the sub-clamp pin 39 of a width link 29 is turned counterclockwise, the backward bending blade 25B is positioned on a sheet metal W, and the backward bending blade 25B is put in parabolic motion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet metal bending press machine of the type in which a sheet metal is sandwiched in an opening at the front end of a C-shaped frame and the sheet metal is pushed and bent by a blade die.

[0002]

2. Description of the Related Art Sheet metal bending presses are known in various forms such as a blade type, a V-bending type, an ironing type, and a side punching type. By ideally capturing the movement trajectory of the, there is an advantage that it is possible to skillfully prevent the generation of scratches and the occurrence of defective products such as waist bending and distortion. In this sense, as a blade type bending press, it has already been disclosed in JP-A-2-
Japanese Patent No. 274317 is known.

According to this publication, in a C-shaped frame in which an upper frame is openably and closably supported on a lower frame,
A link mechanism is formed by pivotally attaching a sub link that is laid sideways to the upper end of the main link that is arranged almost vertically on the lower frame at the tip, and bend the sheet metal upward at the upper end of the main link. A bending mechanism is provided as a lower part, and a reverse bending blade for bending downward is integrally provided as an upper part, and a crank mechanism for swinging the main link at a position almost directly under the blade is provided at a lower end portion of the lower frame. In addition, a crank mechanism for moving the swing shaft of the sub link is provided above the rear end, and the main link swings around the pivot linking pin with the sub link as a fulcrum to bend the upper and lower blades. It has a parabolic orbit suitable for.

However, according to the above-described sheet metal bending press, the mounting form of both blades is a so-called U-shape, and the normal bending blade is located at the lower part of the U-shape. The length of the positive bend is restricted by the size of. In order to solve this, an idea was made to turn the forward bending blade and the reverse bending blade upside down. That is, there is a proposal that the blades are mounted in an arcuate shape or a crescent shape, and the upper portion of the blades is a forward bending blade, so that the forward bending is greatly bent to the size of the inner space of the upper frame. -31342
It is known as JP-A-4.

[0005]

According to the sheet metal bending press machine in which the forward bending blade and the reverse bending blade are vertically reversed in this way, a blade die including both blades is positioned at a height position where the sheet metal is sandwiched. It is necessary to go up and down greatly beyond. Since it was difficult to rationally obtain this vertical movement distance by the crank mechanism, a device for supplementing the movement distance was provided.

In this supplementary device, a drive plate corresponding to the main ring which is moved up and down by a crank mechanism is further equipped with a movable plate which is moved up and down by a fluid pressure cylinder so that the blade mold can be moved up and down in two stages. However, it is difficult to obtain the necessary strength for bending the sheet metal. Also, in order to obtain the trajectory of the blade for forward bending and reverse bending, there is also a back-up device that can adjust the front and rear to receive the drive plate by the roller behind, which makes the device very complicated overall. There was a problem of becoming.

In view of the above situation, the object of the present invention is not only to allow the width of the sheet metal to be bent forward to be as large as the size of the pocket of the upper frame, but also to use the crank mechanism and the ring mechanism. It is an object of the present invention to provide a sheet metal bending press in which the blade die can be moved ideally in a straight line, so that it is not necessary to interpose another device therebetween and the structure is simple.

[0008]

In order to achieve the above object, a sheet metal bending press of the present invention is provided with a front end opening portion of a C-shaped frame in which an upper frame is rotatably supported at a rear end of a lower frame. The receiving die and the pressing die that sandwich the sheet metal are projected inward in a long beak shape, and the lower frame has a main link that oscillates by the main crank mechanism at the lower part with respect to the bending position of the sheet metal, and the rear A blade metal that is equipped with an auxiliary link that swings by an auxiliary crank mechanism that is attached to the main part, connects the auxiliary link to the upper end of the main link with a pivot pin, and bends the sheet metal forward and backward at the upper end of the main link. In a sheet metal bending press with a die attached, the blade die is formed into a shape that allows it to sneak under the beak-shaped protrusion of the die, with the forward bending blade facing upward at the rear end and reverse bending at the front end. The raid is formed in a front-to-back paired shape protruding downward, and the main shaft crank mechanism is provided at the rear position of the lower frame so that the main link swings back and forth and up and down in the forward bending inclination, and the blade mold receives It is characterized in that it is constructed so as to face the normal bending by the posture of diving under the mold.

[0009]

Since the bending press for the sheet metal is constructed as described above, the crank mechanism for swinging the main link is at the rear, and the main link swings up and down and forward and backward in the forward bending posture. The blade die at the upper end can be moved in and out below the receiving die with the pivot pin as the fulcrum, and can be normally bent in the state of being intruded. Further, by changing the position of the pivot pin as the fulcrum by the crank mechanism of the sub link, it is possible to give the orbits suitable for the forward bending blade and the reverse bending blade, respectively.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Referring to FIG. 1, a sheet metal bending press 1 is shown.
Has a C-shaped frame 3, and this C-shaped frame 3
Is composed of a lower frame 5 and an upper frame 7, and the rear upper end of the lower frame 5 and the rear lower end of the upper frame 7 are connected by a pivot 9, and the lower frame 5 is supported by the pivot 9. On the other hand, the upper frame 7 can be opened and closed vertically.

A support member 1 is provided on the front portion of the lower frame 5.
1 is integrated, and a receiving die 13 is provided on the support member 11. A support member 15 is connected to the front portion of the upper frame 7, and a pressing die 17 is provided below the support member 15.

The lower end of the lower frame 5 is connected to the lower end of an arcuate support 19 by a crank pin 21, and the upper part of the front part of the upper frame 7 is supported by a crank mechanism 23. The upper ends of 19 are connected.

With the above-mentioned structure, by driving the crank pin 21 and / or the crank mechanism 23 by a drive mechanism (not shown), the bow-shaped support bar 19 moves up with the pivot shaft 9 as a fulcrum, so that the receiving mold 13 is moved. On the other hand, the presser die 17 is separated, and the sheet metal W is inserted or taken out. Further, when the bow-shaped supporting bar 19 descends with the pivot shaft 9 as a fulcrum, the pressing die 17 approaches the receiving die 13 and is clamped by the sheet metal W.

Since the sheet metal W is pulled out after the final positive bending, not only the size of the inner space 7A of the upper frame 7 but also the opening / closing size influences the final normal bending size.
Further, the opening and closing of the upper frame 7 is performed by the movement of the bow-shaped support 19 suitable for cushioning, and in order to obtain a large degree of opening and closing, not only the crank mechanism of the crank pin 21 of the lower frame 5 but also the upper frame 7 is bow-shaped. Since the crank mechanism 23 for moving the support bar 19 up and down is provided, the upper frame 7 is moved up and down by the upper crank mechanism 23 in a relationship that a small opening and closing is usually sufficient. When the crank mechanism 23 is opened and closed in this way, there is an advantage that the burden of lifting the bow-shaped support bar 19 is reduced.

A blade mold 25 is provided on the inner space 7A of the upper frame 7 near the receiving mold 13 and the pressing mold 17 side.
Is provided, and this blade mold 25 is used for the main link 2
It operates by a link mechanism composed of 7 and the sub link 29.

The blade mold 25 includes a positive bending blade 2
5A and the reverse bending blade 25B are integrally formed in a front-to-back paired form, and the sheet metal W is the forward bending blade 25 at the rear end.
A reverse bending blade 25 at the front end bent upward by A
B folds down.

The receiving die 13 and the pressing die 17 are
It projects inwardly in a beak-like shape of a bird, and in particular, the length of the projection 13A of the receiving mold 13 is increased, and the blade mold 25 is bent under the projection 13A in a normal bending direction. Is started, and at that time, the reverse bending blade 25B is retracted under the protruding portion 13A. This, together with the link mechanism, is the feature of this embodiment.

In this link mechanism for moving the blade metal mold 25, the blade metal mold 25 is fixed to the upper end of the main link 27, and the main link 27 swings up and down and back and forth in a leaning forward leaning posture. , Main link 27
The auxiliary link 29 connected to the upper end of the with a pivot pin 31 is adapted to swing up and down in the forward direction.
A driving crank mechanism 3 is provided at a rear portion of a lower end of the lower frame 5.
3, a main link 27 is swingably connected to the main crank mechanism 33 by a main clamp pin 35. Further, the auxiliary crank mechanism 37 is provided at the upper end of the lower frame 5 slightly behind the center,
An auxiliary link 29 is swingably connected to the auxiliary crank mechanism 37 by an auxiliary crank pin 39.

The swinging of the main link 27 does not center around a fixed point, but swings around a pivot pin 31 that moves in correlation with the sub link 29.
As shown in FIGS. 2 and 3, the trajectory α of the movement of the fulcrum,
Since β has the flexibility to change, the position of the blade mold 25 can be freely set within a certain range. The trajectory of the forward bending blade 25A and the reverse bending blade 25B is determined by the correlation between the movement of the main crank mechanism 33 and the position setting (or movement) of the pivot pin 31 by the auxiliary crank mechanism 37. is there. FIG. 2 shows the movement mainly in the forward bending, and FIG. 3 mainly shows the movement in the reverse bending. The main power for moving the blade mold 25 is transmitted by the main link 27, and the range of rotation of the main crank pin 35 is the range on the side facing the blade mold 25 (range of approximately L).
Therefore (see FIG. 2), in this range, the force acts on the blade metal mold 25 as a boosting force by the leverage principle.

The blade mold 25 has a front-back paired configuration in which a forward bending blade 25A for bending the sheet metal W upward is projected upward at the rear end, and a reverse bending blade 5b for downward bending is projected downward at the front end. In order to prevent it from being supported by the receiving mold 13 during normal bending, in the main body portion of the blade mold 25, the side facing the receiving mold 13 has a slope 25S close to the slope of its lower surface. As shown in FIG. 2, it has a substantially triangular cross-section (see FIG. 2).
It should be noted that even if the forward bending blade 25A and the reverse bending blade 25B are formed separately and are integrally combined in use, it does not violate the gist of the present invention.

When the blade metal mold 25 faces forward bending, as shown by the alternate long and short dash line in FIG. 2, the auxiliary crank pin 39 of the auxiliary link 29 is placed with its center Qa at the upper part of the front end of the pivot pin 31. The trajectory α is taken and the driving crank mechanism 2
The center of the main crank pin 35 of 7 is a point Pa slightly above the front end.
In order to be able to insert the sheet metal W, the blade mold 25
Is in the retracted state as shown by the alternate long and short dash line. Then, in order to face the forward bending, the center of the main crank pin 35 is gradually raised and turned to Pb, Pc and rotated, and the forward bending blade 25A moves along the solid line and the chain line while the forward bending blade 25A moves. Takes a parabolic orbit required for positive bending.

When the body moves to the posture of facing the reverse bending after the completion of the normal bending, the auxiliary crank pin 39 of the auxiliary link 29 is used.
The center of is rotated counterclockwise from the point Qa, and is positioned at a point Qb at the lower end, as shown in FIG. Then,
Since the reverse bending blade 25B is located on the sheet metal W (two-dot chain line), the sheet metal W is thrust by the amount of reverse bending.

Next, in order to face the reverse bending, the center of the main crank pin 35 is changed from Pc to Pd and from Pd to P while the center of the sub crank pin 39 is kept at the point Qb.
It descends and turns to e. At this time, the reverse bending blade 25B comes into contact with the sheet metal W at Pd (solid line position), and further downwardly pivots to the point Pe, the reverse bending blade 25B moves in a parabolic shape, and the sheet metal W is reverse bent to overforming. (Dotted line position).

To return to the normal bending posture, the center of the main crank pin 35 is returned to the point Pc, and the center of the sub crank pin 39 is further rotated counterclockwise to Qc and Qd. Then, in Qc, as shown by the alternate long and short dash line in FIG.
In Qd, as shown by the chain double-dashed line in FIG.
Since it descends while avoiding, the center of the main crank pin 35 and the center of the auxiliary crank pin 39 are respectively set to the first Pa,
Return to Qa (Fig. 2). This time, as the final positive bending, a large width is taken as shown in FIG.

It should be noted that the way of determining the positions of the main crank pin 35 and the sub crank pin 39 is merely an example, and various cases are conceivable. In any case, the lower frame 5
In the above, since the blade mold 25 does not have to descend largely and the main link 27 takes a posture with low forward bending, the height of the support member 11 of the receiving mold 13 is lowered so that it can withstand compression. Can and support member 1
The reinforcing plate 41 can be raised so as to be suitable for supporting 1. Further, the height at which the sheet metal W is inserted is easy to work and can be appropriately lowered. Therefore, not only can the structure be simplified, but it can be made compact as a whole.

[0027]

As described above, according to the present invention, there are the following excellent effects.

The blade mold is formed into a shape capable of submerging under the beak-shaped protrusion of the mold, and a forward bending blade is projected upward at the rear end and a reverse bending blade is projected downward at the front end. Since the blade metal mold is formed so as to face the normal bending while submerged under the receiving metal mold, the sheet metal can be largely bent to the size of the inner space of the upper frame.

Since the crank mechanism is provided at the rear position of the lower frame so that the main link swings back and forth and up and down in the forward bending inclination, ideal forward bending and reverse bending can be achieved only by the link mechanism in the blade mold. It is possible to apply motion, there is no need to intervene with a device for supplementing the driving distance or supplementing the movement, and a strong force can be exerted by the principle of folding, and by the combination of the link mechanism and the crank mechanism. It has a simple structure.

In the lower frame, since the main link does not lean forward and the blade die does not have to be largely lowered, it is not necessary to increase the height of the lower frame, and the support member of the receiving die is compressed. Easy to maintain strength,
The overall structure is compact and inexpensive. Also,
The insertion position of the sheet metal can be set to a height that is easy to work.

[Brief description of drawings]

FIG. 1 is a side view of a sheet metal bending press according to the present invention.

FIG. 2 is an explanatory diagram mainly showing a procedure of forward bending.

FIG. 3 is an explanatory diagram mainly showing a procedure of reverse bending.

[Explanation of symbols]

 W Sheet metal 1 Bending press 3 C-type frame 5 Lower frame 7 Upper frame 13 Receiving die 13A Beak-shaped protrusion 17 Pressing die 25 Blade blade 25A Forward bending blade 25B Reverse bending blade 27 Main link 29 Secondary link 31 Pivoting Pin 33 Main crank mechanism 35 Main crank pin 37 Sub crank mechanism 39 Sub crank pin

Claims (1)

[Claims] 1. A receiving die and a holding die for sandwiching a sheet metal project inward in a beak shape at a front end opening portion of a C-shaped frame in which a rear frame of the lower frame is pivotally supported so that the upper frame can be opened and closed. The lower frame is equipped with a main link that swings by a main crank mechanism at a lower portion and a sub link that swings by a sub crank mechanism at a rear portion with respect to the bending position of the sheet metal. In a sheet metal bending press machine in which a sub-link is connected to the upper end of the main link with a pivot pin, and a blade die is attached to the upper end of the main link for forward and reverse bending of the sheet metal. In addition to forming a shape that can go under the protrusion, a forward bending blade is formed upward at the rear end and a reverse bending blade is formed downward at the front end to form a pair of front and rear, and the main link is bent forward and inclined. The main shaft crank mechanism is provided at the rear position of the lower frame so as to swing back and forth and up and down, and the blade mold is configured so as to face the normal bending with the posture to sink under the receiving mold. Sheet metal bending press machine.