JPH0638579Y2 - Stretch bender - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] Industrial field of application The present invention relates to a stretch bender capable of handling two types of workpieces with a single tension cylinder and eliminating the need for replacement of the tension cylinder. It is a thing.

2. Description of the Related Art Conventionally, in a stretch bender, it is necessary to change the tension force depending on the shape, strength, size, thickness, etc. of the work piece, and depending on the tension force required for that, an appropriate pressure is applied every time the work piece changes. It had the drawback that it had to be replaced with a tension cylinder.

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention The present invention uses a tension cylinder to operate a differential pressure, so that one tension cylinder is provided with two types of tension force, large and small. The tension cylinder of this book can be used, and the stretch bender that does not require replacement of the tension cylinder will be provided.

[Constitution of device]

Means for Solving the Problems In view of this point, the present invention pivotally mounts a rocking table on a work table for fixing a mold, and a tension cylinder is attached to the rocking table, and the rocking table is rocked. In a stretch bender equipped with an operating cylinder, a piston is slidably arranged in the cylinder wall of the tension cylinder, and piston shafts having different diameters are fixed to both sides of the piston, and the tip of the piston shaft is used as a cylinder cover. The above-mentioned drawbacks are not solved by providing a stretch bender that protrudes from the drilled insertion hole.

Action The present invention, when processing a work piece with a stretch bender, if pressure fluid is supplied to one or both of the pressure chambers of the tension cylinder depending on the size of the work piece, two types of tension force, large and small, are obtained to replace the tension cylinder. It can be processed without doing.

Embodiment Hereinafter, one embodiment of the present invention will be described with reference to the drawings. 1 is a workbench arranged in the front center part of a stretch bender, and on the top of the workbench 1, stationary legs 2, 2a ... The mold base 3 is placed and fixed, and the mold 4 is detachably fixed on the mold base 3.

Reference numerals 5 and 5a denote rocking bases projecting laterally from the workbench 1 and pivotally attached to the rocking bases 5 and 5a.
A pair of opposed tension cylinders in which substrates 8 and 8a which are vertically movable by cylinders 7 and 7a are attached to the slide shafts 6 and 6a, and chucks 9 and 9a are fixedly mounted on the substrates 8 and 8a.
10 and 10a are installed.

Reference numeral 11 denotes a base which is erected on the rear side of the work table 1. The operating cylinders 12 and 12a are swingably attached to the base 11, and the tips of the rods 13 and 13a of the operating cylinders 12 and 12a swing. Stand 5,
It is swingably attached to 5a.

The tension cylinders 10 and 10a are differential pressure cylinders, and the piston 15 is slidably arranged in the cylinder wall 14 and pressure chambers 16 and 16a are formed on both sides of the piston 15 in a divided manner. The piston shafts 17 and 17a are fixed, and the tip ends of the piston shafts 17 and 17a are fixed to the cylinder covers 19 and 19a of the tension cylinders 10 and 10a.
It is made to project from the insertion holes 20, 20a formed in the.

Then, depending on the shape and structure of the tension cylinders 10 and 10a, the pressure receiving areas other than the piston shafts 17 and 17a equivalent areas on both sides of the piston 15 facing the pressure chambers 16 and 16a of the two chambers are changed. By supplying more pressure fluid (gas, oil, etc.) to change the pressure acting on both sides of the piston 15, the piston 15 slides.

18 and 18a are O-rings.

Next, the operation of the stretch bender according to the present invention will be described. The work cylinder W is gripped and pulled by the tension cylinders 10 and 10a and the chucks 9 and 9a, and the working cylinder 1
The rocking bases 5 and 5a are rocked by the operation of 2 and 12a, and the mold 4
The workpiece W is pressed into contact with the workpiece W to form the workpiece W into a predetermined shape, and at this time, the pressure chamber 16 of one of the tension cylinders 10 and 10a is processed.
When a pressure fluid is supplied to the piston 1, a large tension force is obtained to process a large work piece W, and when a small work piece W is processed, the pressure fluid is supplied to both pressure chambers 16 and 16a so that the piston 1
Due to the difference in pressure receiving area on both sides of 5, a small tension force is obtained for processing.

[Effect of device]

In short, according to the present invention, the rocking bases 5 and 5a are pivotally attached to the workbench 1 for fixing the mold 4, the tension cylinders 10 and 10a are attached to the rocking bases 5 and 5a, and the rocking bases 5 and 5a are attached. In a stretch bender equipped with operating cylinders 12 and 12a for swinging, a piston 15 is slidably arranged in a cylinder wall 14 of the tension cylinders 10 and 10a, and piston shafts 17 having different diameters are provided on both sides of the piston 15. , 17
Since a is fixed respectively and the tip ends of the piston shafts 17 and 17a are projected from the insertion holes 20 and 20a formed in the cylinder covers 19 and 19a, the pressure receiving areas on both sides of the piston 15 in the tension cylinders 10 and 10a are different. Then, since the tension cylinders 10 and 10a operate at a differential pressure by supplying the pressure fluid of the same pressure, when the workpiece W is processed by the stretch bender, the pressure chambers 16 of the tension cylinders 10 and 10a corresponding to the workpiece W, If pressure fluid is supplied to one or both of 16a, two types of tension force, large and small, can be obtained due to the difference in the pressure receiving area of the piston 15, and the tension cylinders 10 and 10a must be replaced even if the workpiece W is different. It can be processed without.

Further, in the shape and structure of the tension cylinders 10 and 10a that operate with differential pressure, two differently shaped piston shafts 17 and 17a are fixed to both sides of the piston 15 as compared with the conventional cylinder in which one piston shaft is fixed. Since it is only necessary to simplify the shape, structure, and production of the tension cylinders 10 and 10a, its practical effect is enormous.

[Brief description of drawings]

1 shows an embodiment of the present invention. FIG. 1 is a plan view of a stretch bender, FIG. 2 is a front view of the same, FIG. 3 is a sectional view of a tension cylinder operated by a differential pressure, and FIG. It is a circuit diagram of pressure fluid. 1 work table, 4 molds, 5, 5a rocking table 10, 10a tension cylinder 12, 12a working cylinder, 14 cylinder wall 15 piston, 16, 16a pressure chamber 17, 17a piston shaft 19, 19a cylinder cover, 20, 20a Insertion hole

Claims (1)

[Scope of utility model registration request] 1. A swing table is pivotally attached to a work table for fixing a mold,
A tension cylinder is attached to the swing base,
In a stretch bender equipped with an operating cylinder that swings a rocking table, a piston is slidably arranged in a cylinder wall of the tension cylinder, and piston shafts having different diameters are fixed to both sides of the piston. A stretch bender in which the tip of the shaft is projected from an insertion hole formed in the cylinder cover.