In the mold processing, wire cutting is generally a process, so high processing accuracy is required. If the mechanical accuracy of the machine tool is not good, it will directly affect the processing quality of the product and mold, leading to the loss of users and market. Therefore, when selecting the wire EDM machine, it is very important to judge the mechanical accuracy, structure and quality. The following is the explanation from several aspects such as the transmission structure, guide structure and drive mode of the machine tool working table.
First of all, it is necessary to understand the number of gears in the gear box in detail. The more the gears involved in transmission, the greater the transmission resistance, the easier the tooth surface is worn-out, and the greater the gear clearance in transmission. This leads to the greater the system error of the machine tool working table. If the gear assembly is not good, it is easy to produce occasional errors. Therefore, less gears for transmission is better, and it is better to use a pair of gears for transmission with small error. Therefore, when selecting the CNC wire cut machine, it is very important to understand the gear transmission structure of the working table movement.
Carefully observe the working environment and lubrication performance of the gear box. For some early machine tools designed by some manufacturers, the cutting fluid can easily enter the gear box, which makes the gears work in the cutting fluid for a long time. This design is very unreasonable. It increases gear abrasion in light cases and causes stepper motors to burn out due to water intrusion in serious cases. Therefore, when selecting the machine, the user must observe the position of the gear box to ensure that the cutting fluid cannot be immersed. This is very important for the precision and maintenance of the machine tool.
The guide rail of the CNC wire cut machine is the key to ensure the working accuracy of the working table. Users should take it seriously when selecting. First, observe the size of the cross-section of the guide rail. Under the same conditions, the thicker and stronger the guide rail, the better the rigidity and the less likely it is to deform during processing. Secondly, ask the manufacturer about the material and heat treatment process of the guide rail. Generally, high-carbon alloy steel, whole quenching or ultrasonic quenching process is better to ensure its strength and small deformation.
Directly observe the guide rail structure. There are several common guide rail structures in the market: steel ball type rolling guide rail, steel column type rolling guide rail, linear rolling guide rail, and elastic bearing cast iron guide rail.
The difference between the first and second types is the rolling body of the guide rail, one is a ball and the other is a cylinder. The contact between the ball and the guide rail surface is point contact, while the contact between the cylinder and the guide rail surface is linear. Therefore, the wear resistance and bearing capacity of the latter are much better than those of the former. The elastic bearing cast iron guide rail is a simple guide rail and has been eliminated.
Precision CNC wire cut machine is generally driven by stepper motors, which can be divided into reaction type and hybrid type to achieve different step angles. The common one in the market is the reaction type stepper motor. The reaction type stepper motor has different drive modes, such as three-phase three-stage, three-phase six-stage, five-phase ten-stage, five-phase dual ten-stage, etc. This type of motor has a large step angle and only has