What Is a Pitch Changer?
A pitch changer is a numerically controlled automatic lathe.
Materials longer than 2 meters are stored in the machine as they are and automatically fed and processed according to a program prepared in advance.
Since it eliminates the need for material changes and setup changes, this machine can be operated unmanned for long periods of time, enabling continuous mass production.
Pitch changers are capable of machining a wide range of parts unattended, from needle-thin pins to long shafts, because they can handle an outer diameter of 2 mm to a maximum of 20 mm, which is less than a grain of rice, and a machining length of up to 2000 mm.
Uses for Pitch Changers
Items that can be cut using a pitch changer can be made into screws, bolts, shafts, and other parts by cutting and processing materials such as iron, stainless steel, copper, aluminum, titanium, and resin.
Pitch changers are suitable for making all these kinds of parts of all sizes and types from round bars.
Screws and bolts made with pitch changers are used in medical equipment, automobiles, aircraft, railcars, electronic devices, precision equipment, and many other applications.
Principle of Pitch Changers
Pitch changers are programmed by servo motors to move the spindle in the longitudinal direction and the cutting tool in the radial direction.
The amount and speed of movement in the longitudinal and radial directions are controlled by the numerical control method. Therefore, it is necessary to create an NC program for each product and input the program to the machine.
In the latest NC pitch changers, the numerical control unit has been replaced by computer control, and in addition to cutting round workpieces by rotating the spindle, cutting by end milling is also possible as the spindle stopped rotating.
In addition, D-cut, horizontal hole drilling, horizontal tapping, and other additional machining are also possible.
These machines are called computer numerical control (CNC) automatic lathes or CNC automatic lathes, and nowadays, both NC and CNC pitch changers are basically the same.
The advantages are that fine adjustment of dimensions, such as 1 µm, is made by computer with compensation for the amount of movement, which simplifies setting changes and reduces the need for craftsmen’s instincts and tricks, making it easier to hand down skills.
One disadvantage is that machining time is relatively long, even for simple parts, due to the need for programming.