The development history of punch press:
1. Manual press:
2. Manpower press:
3. Power press:
4. Auto punch press:
The application of punch press:
- Applied to metal’s punching, cutting, drawing and compression forming
- Not applied to the fabrication of fragile material (cast iron, wood, glass, and ceramics) and flammable materials (magnesium alloy)
- Suitable for mass production, not suitable for a single production.
- High processing efficiency, the high utilization rate of materials;
- Must be used together with the mold, and mold can only be used to make one product.
I. Basic knowledge of punch press
1.1 brief introduction to press function:
★ The essence of the punch press is translating the circular movement into a straight-line motion.
★ Function: make the use of transmission structure, so that the machine produces the appropriate pressure and kinetic energy near the bottom dead center, together with the mold to make the workpiece resulting in plastic deformation to get the desired workpiece.
Punch press classification as per the slider movement:
Identification of punch points:
Crankshaft and eccentric gear
★ use when stroking < 400
★ low cost
★ use when stroke > 400
★ high cost
2.1 C-type press structure introduction (crank single point)
C frame press component:
A1: Slider Component
A3: Die Cushion
Punch drive structure plan:
2.2 C-frame press (crankshaft double point) structure：
Teach you how to judge the crank punch：
- Crankshaft corresponds to connecting rod–>Connecting rod outside
- Crankshaft corresponds to guide post–>Guide column outside (The probability of being seen on the crankshaft closed punch is only 5%!)
2.3 Closed (crankshaft single point) press structure:
2.4 Closed (crankshaft double point) press structure:
★ Integrated body & three split body
- Integral body:
— Applicable table is relatively small, tonnage is relatively small;
— Tablet generally ≤ 2300 * 1250, tonnage ≤ 260T
- Three split body
— Applicable table is relatively big, tonnage is relatively big;
— Tablet generally ≥2500*1400, tonnage ≥300T
Three split bodies: use 4 reinforcing rod to connect the upper, middle and lower sides to a whole.
Three split body punch press:
2.5 Closed (eccentric gear single point) press structure:
2.6 Closed (eccentric gear double point) press structure:
2.7 High-speed punch press
III. Punch press peripheral equipment
Quick mold changing device: including the upper clamp die, the lower clamp dies, die lifter, die arm, hydraulic power units, etc.
IV. Punch press safety
- For the safety of personnel:
(1). The machine designed safety device: two-hand operation safety device, emergency stop device, and re-start prevention, double solenoid valve, chain devices and so on.
(2). Operating: safety fence, photoelectric safety devices, safety plugs and safety stop, alarm, and so on.
- For the safety of the machine itself
- Overload protection device: If the use of capacity beyond the capacity of the device itself, there will be overload to stop, to protect the machine.
- Thermal relay protection device: to prevent damaging the motor by the too large current.