Today, punch presses are widely used in production, often for stamping and forming of hardware parts in electronics, household appliances, furniture, communications, computers, transportation vehicles (cars, motorcycles, bicycles), etc. Do you specifically know the classification and characteristics of punch presses?

I. According to the driving force of the slider:

a. Hydraulic press (oil pressure type and water pressure type) : Currently, the majority are of the oil pressure type. A small number of large and special machinery use water pressure type.

b. Mechanical punch press: The stamping of sheet metal and most stamping processes are carried out using mechanical punch presses.

Ii. According to the slider drive mechanism:

A. Elbow-joint press: a unique slider movement curve where the slider speed near the bottom dead center slows down (compared with crankshaft press). It can accurately determine the position of the stroke to the bottom dead center, which is more suitable for compression processing such as embossing and finishing. Currently, cold forging is the most widely used.

b. Crankshaft type press: The features of the crankshaft mechanism include easy manufacturing, the ability to accurately determine the motion curve of the slider and the position of the lower end of the stroke, and wide application. Therefore, most presses are crankshaft type presses.

c. Crankless punch press (eccentric gear punch press) : It has advantages over crankshaft type in terms of shaft rigidity, lubrication, appearance, and maintenance.

d. Friction press: It is used for processing such as bending, forming and stretching, and has multi-functional features. Due to its low price, it was once widely used. It is most suitable for forging and crushing operations. Due to its shortcomings such as the inability to determine the lower end position of the stroke, low processing accuracy, low production efficiency, overload when control operation is improper, and the need for proficient skills, it has gradually been phased out.

e. Connecting rod type press: The purpose of the connecting rod mechanism is to keep the drawing speed within the limit during the drawing process and shorten the processing cycle. By reducing the speed variation during the drawing process, the speed of the approach stroke from the top dead center to the processing start point and the return stroke from the bottom dead center to the top dead center is accelerated, enabling the press to have a shorter cycle and thereby enhancing production efficiency. It has long been used for the deep extension of cylindrical containers, with a relatively narrow bed surface. Currently, it is also used in the processing of automotive body panels.

CAM press: Its characteristic is to create an appropriate CAM shape so as to easily obtain the desired slider motion curve. However, due to the nature of the CAM mechanism, it is difficult to convey a large force, so its capacity is relatively small.

g. Rack and pinion press: In the early stage, it was used for pressing bushings, squeezing debris and other items, baling, oil extraction, and extruding cartridge cases (thinning processing in hot rooms), etc. Currently, it has gradually been replaced by hydraulic presses.

h. Screw press (screw press) : Less used and gradually phased out.

Iii. According to the movement mode of the slider:

a. Single-action press: It is currently the most widely used.

b. Compound press: Less frequently used (for car bodies)

c. Three-motion punch press: Used in smaller quantities (for drawing processing of large workpieces)