Feeding device and shearing machine tool in shearing machine design
When cutting a thin plate, if the cut-out part is long and the table is long, the sheet is easy to bend downwards. Therefore, the feeding device should be considered. There are two kinds of feeding devices: one is to drag up from the bottom surface of the material to be cut. Live, the other is to suck from the sheared sheet.
In the loading device that is dragged from the bottom surface, the loading swing rod is in a horizontal position when the electromagnet is working, and the sheet material is dragged. The electromagnet is disconnected before the shearing starts, and the load swinging rod is swung downward due to its own weight.
The electromagnetic roller device that sucks the sheet from above. The electromagnetic roller device is composed of several sets of electromagnetic rollers, and the electromagnetic rollers are installed in the holes of the bracket, and each bracket is suspended by two tie rods on the horizontal plate of the tool holder. When the electromagnetic roller is not needed, the pull rod can be lifted and the bolt rotated by 180°, and the shearing force of the shearing machine is determined. The sheet is free to pass. The diameter of the hole is slightly larger than the support shaft diameter of the electromagnetic roller, and the corresponding electromagnetic roller is lifted when the sheet is locally raised. The suction force of the electromagnetic roller can be adjusted to be slightly larger than the weight of the portion to be cut, and if the suction force is smaller than the weight of the sheet to be cut, the sheet is easily bent downward. The value of the suction can be determined according to the number of rolls in contact with the sheet. If the suction is too large, several sets of rolls can be lifted, or one end of the support can be brought into contact with the partial rolls and the sheet.
Consider the cost and simplicity, so choose the former one.
The lower blade of the shearer has four blades. The blade on the shearing machine in which the tool holder moves linearly forward can have two or four edges. The blade on the shearing machine that moves along the arc should have only two blades, and the upper blade must be adjusted to a space surface with screws or spacers, so the length of the upper blade is increased as much as possible to reduce the number of seams. Improper adjustment of the seam will result in increased tool wear and increased deviation of the edge of the plate.
The top surface of the blade should be slightly lower than the work surface with a deviation of -0.20 mm.
The domestic shearing machine blade material is commonly used 6CrW2Si, (hardness after heat treatment is RC58-60). T7A, 9CrSi, Cr12P1, Cr12Mo and Cr6VP can also be used as the material of the blade. Foreign experimental cemented carbide BK15 or BK20 is placed on the scissor blade to increase the interval between two sharpenings.