CNC tool grinder diamond grinding wheel dressing method

The use of CNC tool grinder

Diamond grinding wheel directly affects the normal use of CNC tools, a small part, sometimes may cause the failure of the whole project, so, today to introduce the CNC tool grinder diamond grinding wheel automatic dressing and compensation method.

With the development of automatic CNC grinding technology, high requirements have been put forward for its supporting equipment.

As one of the supporting technologies, the on-line automatic grinding wheel dressing technology must meet the needs of modern CNC grinding technology and make it develop towards the direction of high precision, super stability and full automatic control.

As an efficient grinding tool, diamond grinding wheel is widely used in the processing field of hard alloy, ceramics, CBN and other super hard materials.

The dressing and automatic compensation method of diamond grinding wheel determines the performance of automatic CNC grinding machine and determines the performance and service life of the grinding wheel to a great extent.

Principle of diamond grinding wheel dressing

Dressing method of diamond grinding wheel is an important factor affecting the grinding performance of the wheel. The reasonable choice of dressing method will directly affect the surface quality and grinding precision of the workpiece.

At present, the commonly used dressing methods of diamond grinding wheel are: on-line electrolytic dressing, electric spark grinding wheel dressing, cup grinding wheel dressing, electrochemical-mechanical compound dressing and laser dressing.

Since the dressing method of cup wheel is simpler and easier to implement than other dressing methods, GC cup wheel dressing technique is adopted in this paper to perform automatic dressing of diamond wheel.

The dressing of diamond grinding wheel, a kind of super hard abrasive, is usually divided into two stages: shaping and sharpening.

The purpose of shaping is to remove the shape error and surface defect of the grinding wheel after initial installation and to ensure the geometric shape precision of the grinding wheel.

Sharpening is due to the passivation of the grinding wheel after working for a period of time. In order to make the cutting edge protruding the binder and having an appropriate height, sufficient chip tolerance space should be formed between the grinding grains, and the effective number of grinding grains per unit area should be as large as possible.

Method of dressing bowl diamond wheel by GC cup wheel

During actual dressing, the geometric relationship and motion form between GC cup wheel and bowl-diamond wheel are shown in Figure 1.

The bowl diamond wheel and the GC cup wheel grinding belt are completely staggered and fitted. They are respectively rotated at a certain speed. The rotational linear speed ratio of the dressing wheel and the grinding wheel is set at 8:1.

The dressing wheel is fixed, and the diamond wheel is dressed and fed along the axis, so that the GC cup wheel and the bowl diamond wheel form mutual abrasive grinding.

By grinding the end faces of the two grinding wheels, the passivated abrasive particles of the diamond grinding wheel are removed to form a chip tolerant space, and the surface of the diamond grinding wheel is re-sharpened to achieve the purpose of dressing.

Automatic control method of grinding wheel dressing

In grinding, the wear state of the grinding wheel is an important factor affecting the grinding quality.

The nc tool grinder can monitor the grinding wheel status in real time during the whole process of blade grinding.

Depending on the size and material of the machining blade, the volume and grinding time required to be removed by grinding will vary.

Taking all factors into consideration, set the interval of automatic dressing.

By counting the number of times the grinding blade of the grinding wheel and comparing it with the dressing interval set by the system in real time.

When the grinding times reach the set dressing interval times, the dressing module is automatically called in the NC program to realize the automatic dressing of the grinding wheel.

In order to ensure the safety of machine operation, the control method also includes the real-time monitoring of grinding wheel life and dressing wheel life.

As long as it is detected that the dressing may cause the grinding wheel or dressing wheel to reach the warning thickness, the machine will automatically send an alarm signal and stop for manual processing.

If neither the grinding wheel nor the dressing wheel reaches the alarm thickness, the dressing will proceed smoothly.

After dressing, the compensation value of grinding wheel dressing is output through data processing.

Compensation method for grinding wheel dressing

The consistency of workpiece size depends largely on the consistency of process system state.

After the grinding wheel is dressed once, the abrasive thickness decreases and the grinding wheel end face changes to the designated calibration position, which leads to the change of the state of the whole process system and the size of the workpiece to be processed, so the size consistency cannot be guaranteed.

Therefore, it is very important to compensate the grinding wheel after dressing.

The analysis of grinding wheel dressing process is the mutual grinding of two abrasives. The abrasive thickness of the grinding wheel will not only decrease, but also the abrasive thickness of the dressing wheel will also decrease, which is the result of a comprehensive action.

Therefore, the compensation method of grinding wheel dressing is determined by multiple tests.

The hardness and wear resistance of diamond grinding wheel are much higher than GC cup dressing wheel.

It can be predicted that during a dressing process, the abrasive thickness reduced by diamond grinding wheel is far less than that reduced by dressing wheel.

As shown in FIG. 4, the dressing wheel is fixed in position. During dressing, the grinding wheel advances a dressing amount along the feed direction. Due to the interaction of grinding, the thickness of the grinding wheel and the dressing wheel decreases simultaneously.

The relationship between them is: dressing amount = reduction of grinding wheel Dressing wheel reduction.

In order to ensure the size consistency of the workpiece to be processed, the reduction of the grinding wheel after dressing should be compensated.

The actual dressing test data show that when the dressing amount is 0.03mm, the thinning of grinding wheel is 0.0015mm and the thinning of dressing wheel is 0.0275mm.

CNC tool grinding machine after the introduction of diamond wheel, hope for the future work can help, an grinding machine group co., LTD is one of the five-axis CNC tool grinding pioneer in China, from 2009 began to launch five-axis CNC tool grinding machine, is a professional CNC grinding machine manufacturers, the company welcome the presence and the choose and buy.

PRCTOOLS is an experienced suppliers of diamond and CBN grinding tools,Our product is certified by MPA,Quality assurance!!!

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