A centerless grinding machine is a type of grinding machine that does not require grinding of the axial center of the workpiece.

Centerless Grinder

It is mainly composed of three mechanisms: grinding wheel, adjusting wheel and workpiece holder.

Among them, the grinding wheel actually works as a grinding machine.

The adjustment wheel controls the rotation of the workpiece and controls the feed rate of the workpiece.

As for the workpiece holder, the workpiece is supported during grinding.

There are several ways to match these three types of parts, except for stopping grinding, which is the same in principle.

Introduction

A centerless grinding machine with a reduced lateral dimension.

The centerless grinding machine is particularly suitable for use in a small installation space and is capable of meeting the simplification and space saving requirements of various production lines.

Since the grinding wheel finishing unit is disposed at an obliquely downward position above the grinding wheel, it is not necessary to maintain a space for the grinding wheel finishing unit on the side of the grinding wheel.

This space is most closely related to the lateral dimensions of a conventional centerless grinder.

Thereby, the lateral dimension of the centerless grinding machine can be greatly reduced.

The ability to mount the grinder in a small installation space meets the simplification and space saving requirements of various production lines.

Principle

A grinding machine that uses a centerless grinding method to grind a rotating surface of a workpiece, usually referred to as a centerless cylindrical grinding machine.

In the centerless cylindrical grinding machine, the workpiece is not centered and supported, but placed between the grinding wheel and the guide wheel, supported by the pallet and the guide wheel.

The grinding wheel is usually installed at the end of the main shaft, and the grinding wheel with a width of more than 250 mm is installed in the middle of the main shaft. The maximum width of the grinding wheel is 900 mm.

The grinding wheel rotates at high speed for grinding, and the guide wheel rotates in the same direction at a slower speed to drive the workpiece to rotate for circumferential feeding.

Through the grinding, the axial feed is realized by adjusting the slight inclination angle of the guide wheel axis, and is suitable for grinding the elongated cylindrical workpiece, the short shaft without the center hole, and the sleeve type workpiece.

When cutting into the grinding, radial feed is achieved by the movement of the guide wheel frame or the grinding wheel frame, which is suitable for grinding workpieces with shoulders or bosses, as well as cones, spheres or other workpieces whose curves are curved.

Centerless grinding machines have high productivity, and are easy to automate with various loading and unloading devices. Most of them are used for mass production and can be operated by less skilled workers.

Centerless grinding machines generally have a grinding accuracy of 2 microns and a dimensional accuracy of 4 microns. High-precision centerless grinding machines are available in 0.5 micron and 2 micron, respectively.

In addition, there are centerless internal grinding machines and centerless thread grinding machines.

Centerless grinders are automatically trimmed and automatically compensated.

The guide roller feed guide is a double V-type needle roller guide wheel, which is fed by a servo motor and can compensate with the dressing of the grinding wheel.

The machine is equipped with an automatic loading and unloading mechanism for automatic cycle grinding.

Processing methods

There are three main grinding methods for centerless cylindrical grinding machines:

  • Pass-through grinding
  • Plunge and cut through grinding
  • Through centerless grinding

The workpiece is ground in the direction of the grinding wheel axis for grinding.

Adjust the axial inclination of the guide wheel by adjusting the slight inclination of the guide wheel axis.

Suitable for grinding elongated cylindrical workpieces.

Short shafts and nested workpieces without center holes.

Plunge centerless grinding: There are axial positioning fulcrums on the pallet. The workpiece is supported at a certain position on the pallet, and is ground by a grinding wheel or a guide wheel.

For grinding workpieces with shoulders or bosses as well as cones, spheres or other rotating parts.

Plunge-through centerless grinding is the compounding of the two.

In addition, there are tangential feed grinding and end-feed grinding of the stepped workpiece in the axial direction.

Centerless cylindrical grinding machines have higher productivity.

It is mostly used for mass production and is easy to automate.