On the types and characteristics of sheet metal bending machine

Release time：2021-10-12　　　　 Browse times

Sheet metal folding machine is to use the simplest general die to bend the sheet metal in a straight line at various angles. It is the most widely used bending equipment. The plate folding machine has the advantages of simple operation, low cost and convenient replacement. The machine itself only makes up and down reciprocating linear motion.

Bending machine has a wide variety of specifications, various structural forms, increasing functions and increasing accuracy. It has developed into a precision metal forming machine tool. According to the driving mode, the commonly used folding machines include mechanical sheet metal bending machine, hydraulic sheet metal bending machine and pneumatic bending machine.

1. Mechanical sheet metal bending machine

The structural characteristics and working principle of the mechanical sheet folding machine are the same as those of the mechanical press. The crank connecting rod mechanism is also used to change the rotating motion of the motor into the reciprocating motion of the slider.

Mechanical folding machine has huge mechanism and high side manufacturing cost. It is often used for bending medium and small parts.

The advantage of mechanical bending machine is that the parallel accuracy of sliding block and worktable is far away, and it can bear eccentric load. However, with the development of powder hydraulic bending machine, these advantages are not obvious.

The block points of the mechanical folding machine are:

① The stroke and speed cannot be read;

② The pressure cannot be controlled, and the equipment cannot reach the fixed pressure in most of the sliding block stroke cycle;

③ The operation is difficult, and the sealing height of the machine shall be carefully adjusted before operation;

④ The structure layout of the machine is difficult to realize numerical control and automatic operation.

Because the slider speed of the mechanical bending machine cannot be adjusted, the high bending speed will bring danger to the operator and easy to cause personal accidents. When a large sheet is folded, the sheet will produce proud bending, which will affect the shape and accuracy of the parts. With the rapid development of hydraulic technology and hydraulic bending machine, hydraulic bending machine has become the mainstream of sheet metal folding equipment, and mechanical bending machine is gradually withdrawing from bending machine a city.

2. Hydraulic sheet metal bending machine

The rolling sheet metal bending machine adopts hydraulic control. The hydraulic system can exert full pressure on the sheet metal in the whole stroke, the over cutting can be automatically protected, and it is easy to realize automatic control. The upper die 3 divided into several sections is connected with the slider 4 through a hydraulic pad. When bending sheet metal, the oil in the hydraulic pad can extrude part under the action of Leli, the upper die phase, and make a small amount of retraction movement to the sliding block; When the slider returns, the hydraulic system makes up oil to the hydraulic male, and the upper die is relative to the x position of the slider, so the bending angle of the workpiece does not depend on the bottom dead center position of the block. Therefore, it is not necessary to accurately control the stroke of block cleaning. At the same time, hydraulic AA can ensure uniform pressure on the workpiece along the whole length of the worktable, so that it is not affected by the burning degree of the sliding block and l worktable.

A set of cylinder wedge mechanism is used to adjust the upper and lower dishes of the movable V block 5 of the lower die. When the piston rod of the instrument cylinder moves to the right under the action of compressed air, the lower wedge 3 connected to it also moves to the right and pushes the L chess block 4 and the cushion block 5 to overcome the resistance of the plunger in the two small gas siphons 2, so as to move the movable block 5 and the concave chess base plate 6 to e, that is, increase the curvature angle of the workpiece; When the piston rod drives the lower wedge to move to the left, under the action of the air pressure in the small cylinder, the column cold pushes the cushion block and the upper wedge to move downward. The well is close to the lower wedge, so the movable cushion block drops, that is, the bending angle of the workpiece is reduced. Because the above pepper block mechanism has large stiffness, it can ensure that the curved angle of the workpiece remains unchanged after adjustment.