Classification of precision punching machines

With the development of industry, punching equipment is constantly being updated and as a result more and more different performance punching machines are available. So, what are the precision punch presses? 

At present, the main categories of precision presses are as follows.

Knuckle Press

Those using an elbow joint mechanism in the roller drive are called knuckle presses. This type of precision press has a unique roller movement curve where the roller rate becomes very slow near the lower dead center (as measured by the crankshaft precision press).

It also correctly determines the dead point under the stroke and is therefore suitable for compression processes such as presswork and casting and rolling, and is most commonly used in cold forging today.

Screw Press: 

The use of a screw mechanism in the roller drive mechanism is known as a screw press (or screw press).

Friction Press 

Precision presses that use a friction drive and a screw mechanism in the rail drive are called friction presses. This type of press is most suitable for forging and pressing work, and can also be used for bending, forming and drawing, etc. It has a versatile function and was commonly used before the war due to its low price.

They are slowly being phased out due to the inability to determine the position of the lower end of the stroke, poor dimensional accuracy, slow production speed, overloading due to incorrect control operations and the need for technical skill in their use.

They are slowly being phased out due to the inability to determine the position of the lower end of the stroke, poor dimensional accuracy, slow production speed, overloading due to incorrect control operations and the need for technical skill in their use.

Rack Press

The use of a rack and pinion mechanism in the roller drive mechanism is known as a rack and pinion press. Screw precision presses have almost the same characteristics as rack and pinion precision presses, and their features are approximately the same as those of hydraulic precision presses.

They were formerly used for pressing in bushings, crushing slag and other objects, pressing oil, bales, and pressing out shells (hot extrusion thinning), etc., but have now been replaced by hydraulic precision punching machines, which are no longer used except in very special cases.

Cam Press

Precision presses that use a cam mechanism in the roller drive mechanism are called cam presses. This type of precision press is characterized by the use of a properly shaped cam, which makes it easy to obtain the desired curve of roller movement. However, due to the nature of the cam mechanism it is difficult to transmit large forces, so the capacity of this type of precision press is very small.

Link Press 

Precision presses that use various mechanical structures in the roller drive mechanism are called link presses.

The purpose of the mechanical structure is to maintain the drawing rate within the limit while reducing the cycle time during the drawing process. By reducing the speed variation of the drawing process, the approach stroke from the upper dead center to the start of the process and the return stroke speed from the lower dead center to the upper dead center are accelerated, resulting in a shorter cycle time than that of a crankshaft precision punching machine, thus improving productivity.

These precision presses have been used since ancient times for deep drawing of cylindrical vessels with a narrow bed, and more recently for the processing of automotive body panels with a wider bed.

Crank Press 

The majority of mechanical precision presses use this mechanism.

The reason for using the crankshaft mechanism most often is that it is easy to make, the end positions under the stroke can be correctly determined, and the slide movement curve is basically practical for all kinds of processing.

As a result, this type of press is used for punching, bending, drawing, hot forging, warm forging, cold forging and most other precision punching operations.

Crankless Press

Crankless presses are also known as eccentric gear presses.

The function of the crankless press and the eccentric gear press are measured. The eccentric gear press structure is superior to the crankless press in terms of shaft stiffness, wetting, surface and maintenance.

When the stroke is long, the eccentric gear type precision punching machine is more favourable, while in the case of short stroke of special punching machines, the crankshaft precision punching machine is better, therefore small machines and high-speed precision punching machines for punching and cutting are the field of crankshaft punching machines.

Main machine characteristics of Samhoor high-speed punching machines：

1. High speed punching machine with high number of slider strokes.

The number of strokes of the slider, i.e., the number of strokes per minute, is also related to the height of the loading die and the specific feed distance in the specific application of the high-speed punching machine.

2. High speed presses are equipped with ram equalization equipment and foot shock absorbers.

High speed presses have a much higher number of reciprocating movements than other types of presses, resulting in a very high press inertia, which, if not removed immediately, will not only jeopardize the accuracy of the press, but also reduce the life of the press and the die.

3. High-speed presses are equipped with an emergency brake as standard.

4. High press accuracy and feed accuracy.

5. High-speed presses with high rigidity and precision of slide guidance.

6. Auxiliary equipment for high-speed presses is available.

High-speed presses are available with a complete range of auxiliary equipment, such as the usual high-precision gap feeding equipment, equalization equipment and vibration and sound damping equipment, to ensure that they can be used to their full potential as very efficient presses.