Introduction and function of punching machine



Introduction and function of punching machine

The punch is a punch press. In national production, the stamping process has the advantages of saving materials and energy, higher efficiency than traditional mechanical processing, low technical requirements for operators, and making products that cannot be achieved by mechanical processing through various mold applications. Its uses are becoming more and more extensive.
Stamping production is mainly for plates. Through the mold, it can make blanking, punching, forming, deep drawing, trimming, fine blanking, shaping, riveting and extrusion parts, etc., which are widely used in various fields. For example, we use switch sockets, cups, cupboards, dishes, computer cases, and even missile aircraft... There are a lot of accessories that can be produced through molds with a punch.

The design principle of the punch press is to convert circular motion into linear motion. The main motor generates power to drive the flywheel. The clutch drives the gear, crankshaft (or eccentric gear), connecting rod, etc., to achieve the linear motion of the slider. The movement of the connecting rod is a circular movement.
Between the connecting rod and the sliding block, there needs to be a transition point for circular motion and linear motion. There are roughly two mechanisms in its design, one is ball type, the other is pin type (cylindrical type), through which circular motion Converted into linear motion of the slider. The punch presses the material to deform it plastically to obtain the required shape and precision. Therefore, it must be matched with a set of molds (upper mold and lower mold), the material is placed in between, and the machine applies pressure to deform it , The reaction force caused by the force applied to the material during processing is absorbed by the punch machine body.

According to the driving force.The driving force of the slider can be divided into two types: mechanical type and hydraulic type. Therefore, punch presses are divided into different driving forces according to their use:
(1) Mechanical Power Press
(2) Hydraulic Press

A hydraulic press is a press that uses a hydraulic cylinder to generate compression force. The hydraulic press was invented by Joseph Brama of the United Kingdom. In 1795, he invented the hydraulic press and applied for a patent. After studying the literature on fluid motion at that time, Brahma applied his concept to the punching machine.The hydraulic press is based on the Pascal principle: the pressure of the closed system is a fixed value. A part of the hydraulic press is a piston, which acts like a pump. Its cross-sectional area is small and produces a small force. The other part is a piston with a larger area. The pressure of the two is the same, and the piston with a larger area exerts a larger force. If the pump and the press hydraulic cylinder are separated, only a small diameter pipe is needed to connect the pump and the hydraulic cylinder, which is easier to resist the liquid pressure.
When the piston moves, the liquid (such as hydraulic fluid) in the hydraulic cylinder will also move with it. Assume that the liquid is not compressible. The oil volume affected by the small piston displacement is equal to the oil volume affected by the large piston displacement. Therefore, the displacement distance of the two will be different, which is inversely proportional to the piston area. Therefore, in order for the large piston to move, the small piston needs to travel a long distance. The large piston has a larger output, but has a shorter displacement, and a smaller piston receives a smaller force but has a longer displacement, so it conforms to the law of conservation of energy. If the area of the large piston increases, its moving distance will be shorter.
The concept of hydraulic presses can also be used in the hydroforming process.

Mechanical punching machine, also known as mechanical punching machine, uses compressed air provided by a compressed air pump to enter the cylinder through a solenoid valve, and drives the piston to the spindle to make the spindle move downwards, thereby forming an impulse and causing the workpiece to produce regulations in the mold. The deformation to achieve the purpose of processing. The products or parts produced by mechanical punch presses or hydraulic machine tools are called stamping parts. The basic components: stamping power, male molds, female molds, and the raw materials of the products (usually metal sheets or wires). The machine tool drives the public under the action of stamping power. The opening and closing of the mold and the master mold and the process of cutting, punching, stretching and other shaping of the raw materials between them is the operating principle of the stamping machine tool.
Also known as a mechanical punching machine, it uses compressed air provided by a compressed air pump to enter the cylinder through a solenoid valve, and drives the piston to the spindle to make the spindle move downwards, thereby forming an impulse and causing the workpiece to produce a prescribed deformation in the mold. To achieve the purpose of processing. In order to facilitate the use of customers, an electrical control part is added to the equipment. It greatly improves the efficiency of work.

How to avoid punch injury accidents during precision punch operation?

Precision punching machines are widely used in various mass production of sheet metal processing, stamping, forming and stretching. Such as transportation vehicles, clocks and watches, home appliances, stationery, hand tools, hardware, computers and other products processing. At the same time, an automatic feeder can also be installed to engage in automatic conveying and processing of the entire production line. As a processing machine, if there is a mistake or a problem with the machine during operation, it will cause an accident. Therefore, we need to understand how to avoid punching accidents.

Use hand safety tools
The use of manual safety tools can avoid accidents caused by unreasonable mold design and sudden equipment failure. Common safety tools are: elastic plus pliers, special plus pliers, magnetic suction cups, tweezers, pliers, hooks, etc.
Take protective measures for the mold
Taking protective measures for the mold includes setting a protective plate (cover) around the mold and improving the mold structure. For example, reduce the dangerous area of ​​the mold, expand the safety space, set up a mechanical ejection device, and improve the original single-process molds of various manual ejections without affecting the strength of the mold and product quality, and improve safety.
Install safety protection device
Setting up safety protection devices on the stamping equipment and molds, or using hand tools with low labor intensity and convenient and flexible use are also effective measures to realize the safety of stamping operations under current conditions. Such as the use of hand tools, mold protective covers, mechanical access devices, dual-button switches, mechanical handles, push and dial hand devices, photoelectric automatic protection devices, etc. There are many types of protection devices for stamping equipment, which are divided into mechanical, button, photoelectric, and induction types according to the structure. The mechanical protection device is simple in structure and convenient to manufacture, but it has a large interference to the operation, and the operator does not like to use it, and the application is relatively small.
The photoelectric device consists of a set of photoelectric switches and mechanical devices. When the operator's hand enters the mold area, the beam is blocked and an electrical signal is sent out, so that the slider stops working and cannot be lowered, ensuring the safety of the operator. There are two types of photoelectric protection devices: infrared photoelectric protection devices and incandescent photoelectric protection devices. Since the photoelectric protection device is easy to use and basically has no interference to the operation, the punch press is widely used.
The contact protection device uses the sensing element of the contact rod to control the movement of the slider. There are two types: normally open and normally closed. The protection device has simple structure, low production cost and convenient operation. Workers can use several sets of devices in series at the same time when working. It is suitable for presses equipped with friction clutches and presses with modified rigid clutches.

The above is how to avoid punching accidents, I hope it will be helpful to everyone! If you want to know more about precision presses, you can pay more attention to our website. If you need to buy precision punching machines and other machinery, you can contact us directly!