CN102773803A - Precise finishing method of large abrasive grain diamond grinding wheel - Google Patents

Abstract

The invention discloses a method for finely dressing a large abrasive diamond grinding wheel, which relates to a diamond grinding wheel processing method. The method solves the problems of low efficiency and high cost existing in traditional precision machining of hard and brittle materials. The method comprises the following steps: step 1, placing a square Cr12 steel block on a longitudinal magnetic workbench, and controlling a large abrasive grain diamond parallel grinding wheel to plane grind the Cr12 steel block in the mode of transverse feed grinding through a numerical control program; step 2. Clamp the dressing shaft with the cup-shaped diamond roller on the fixture, and then attach it to the magnetic worktable of the machine tool. Use the frequency converter that comes with the dressing system to control and adjust the speed of the cup-shaped diamond roller. Adjust the speed to 1200 -1800r/min, through the relative movement of the cup-shaped dressing roller and the large abrasive diamond parallel grinding wheel 1. The invention is used for fine dressing of large abrasive diamond grinding wheel.

Description

Precise Dressing Method of Large Abrasive Diamond Grinding Wheel

technical field

The invention relates to a diamond grinding wheel processing method.

Background technique

At present, in the processing of hard and brittle materials, most of them first use the rough machining method with high processing efficiency, then use the semi-finishing method with better processing surface, and finally use fine-grained or granular grinding wheels for precision/ultra-precision machining . In this way, two to three processes are used continuously for processing, and different grinding wheels are replaced in each process, resulting in high processing costs and low overall grinding efficiency. Moreover, the chip space is very small when the fine-grained/micro-particle grinding wheel is processed, and more particles will fall off, which may not meet the requirements of processing accuracy. Moreover, the irregular arrangement and aggregation of abrasive grains on the surface of the grinding wheel cause periodic dressing, which makes it difficult to improve processing efficiency. In view of this situation, if the large-grain diamond grinding wheel can be used for precision grinding, the process from rough machining to precision machining can be completed without changing the grinding wheel, which can greatly improve the processing efficiency.

In addition, most of the resin-bonded or metal-bonded diamond grinding wheels are used to grind the ductile domain of hard and brittle materials such as optical glass. However, the resin bond grinding wheel is not suitable for heavy-duty grinding, and the wear rate of the grinding wheel is high, which limits the surface quality and shape accuracy of the workpiece, and causes changes in the morphology and composition of the abrasive grain layer. The metal bond grinding wheel tends to generate heat during the grinding process and is easily blocked by grinding debris. Therefore, the grinding wheel must be trimmed repeatedly, which reduces the grinding efficiency and increases the processing cost. The electroplated metal bond in the electroplated grinding wheel ensures the required high contact rigidity and abrasive support rigidity, the manufacturing process is simple, the investment is small, and the protruding height of the abrasive grains is 1/3 of the diameter of the abrasive grains. The brazed grinding wheel uses active metal elements to form a chemical metallurgical bond at the interface between the metal solder and the abrasive grains, which greatly improves the holding strength of the bond to the abrasive grains, so only a thin bond thickness is enough to firmly hold the grinding wheel. grains, and its exposed height can reach 70% to 80%. The high protruding degree of the abrasive grains not only improves the sharpness of the diamond grinding edge, but also greatly expands the space for chips. The utilization rate and the service life of the grinding wheel are significantly improved. Thus, the application of large abrasive wheels can greatly reduce production costs. If the satisfactory processing effect can be achieved by effectively controlling the processing parameters, it will certainly provide a favorable reference value for the development of grinding technology. However, if the large abrasive wheel is to achieve precision grinding, it needs to be trimmed in time and effectively, which is particularly important.

Contents of the invention

The purpose of the present invention is to provide a method for precision dressing of a large abrasive diamond grinding wheel, so as to solve the problems of low efficiency and high cost in existing traditional precision machining of hard and brittle materials.

The technical scheme adopted by the present invention for solving the above-mentioned technical problems is: the method includes the following steps: Step 1, install a large abrasive diamond parallel grinding wheel on a plane precision grinding machine, place a square Cr12 steel block on a magnetic workbench, and The program controls the large-abrasive diamond parallel grinding wheel to process the Cr12 steel block in the way of transverse feed grinding, and measures the rotation error of the large-abrasive diamond grinding wheel until the rotation error value is less than 10 μm;

Step 2: Clamp the dressing shaft equipped with the cup-shaped diamond roller on the fixture, and then attach it to the magnetic worktable of the machine tool. Use the frequency converter that comes with the dressing system to control and adjust the speed of the cup-shaped diamond roller. 1200r-1800r/min, through the relative movement of the cup-shaped diamond roller and the large-grain diamond parallel grinding wheel, the wear of diamond abrasive grains is generated, and the rotation error of the large-grain diamond grinding wheel is measured until the rotation error value is less than 5μm.

The present invention has the following beneficial effects: the present invention breaks through the traditional optical glass processing procedure, applies the large abrasive diamond grinding wheel to the precision grinding process of hard and brittle materials, and uses the Cr12 steel block and the cup-shaped diamond roller to pair the electroplated grinding wheel The precision dressing of the electroplated grinding wheel reduces the radial rotation error and the axial height gradient difference, so that the surface quality of the workpiece after grinding is significantly improved, and the precision machined surface (Ra≤0.02μm) can be obtained efficiently. The invention solves a series of problems such as low precision grinding efficiency of optical glass and frequent replacement of grinding wheels to a certain extent, and realizes high-efficiency and high-quality optical glass plane precision machining with a large abrasive grain electroplated diamond grinding wheel.

Description of drawings

Fig. 1 is a schematic diagram (side view) of Cr12 dressing method for grinding wheel, Fig. 2 is a schematic diagram (top view) of Cr12 dressing method for grinding wheel, and Fig. 3 is a schematic diagram (side view) of dressing method for grinding wheel with cup-shaped diamond roller, Fig. 4 is a schematic diagram (top view) of a method for dressing a grinding wheel with a cup-shaped diamond roller, and Fig. 5 is a flow chart of the method of the present invention.

Among them, a large abrasive diamond parallel grinding wheel 1, a Cr12 steel block 2, a fixture 3, a cup-shaped dressing roller 4, and a dressing shaft 5.

Detailed ways

Specific embodiment one: illustrate this embodiment in conjunction with Fig. 1-Fig. 5, described method of this embodiment comprises the following steps: Step 1, install large abrasive grain diamond parallel emery wheel 1 on the plane precision grinding machine, square Cr12 steel block 2 Placed on the longitudinal magnetic workbench, the large abrasive diamond parallel grinding wheel 1 is controlled by the numerical control program to process the Cr12 steel block 2 in the way of transverse feed grinding, and the rotation error of the large abrasive diamond grinding wheel is measured until the rotation error value is less than 10μm;

During the dressing with Cr12 steel block 2, due to the dry grinding method and the graphite and iron filings generated during the dressing process, the large abrasive grain diamond parallel grinding wheel 1 is slightly blocked, which accelerates the heat accumulation and catalyzes the diamond grinding process. The wear of the grains effectively reduces the rotation error of the grinding wheel. During the dressing process, it is necessary to sharpen the clogged grinding wheel with oil stone in time. Because no coolant is added, the grinding wheel will have a certain amount of thermal deformation, and thermal expansion and contraction will occur successively, which will affect the improvement of the grinding wheel rotation error to a certain extent.

Step 2: Clamp the dressing shaft 5 equipped with the cup-shaped diamond roller 4 on the fixture 3, then attach it to the magnetic worktable of the machine tool, and use the frequency converter that comes with the dressing system to control and adjust the speed of the cup-shaped diamond roller 4 , adjust the speed to 1200r-1800r/min, through the relative movement between the cup-shaped diamond roller 4 and the large abrasive diamond parallel grinding wheel 1, the wear of diamond abrasive grains is generated, and the rotation error of the large abrasive diamond grinding wheel is measured until the rotation error value is less than 5μm;

In the dressing with the cup-shaped diamond roller 4, the cup-shaped diamond roller 4 is a metal bond. When clogging occurs, use ELID (on-line electrolytic sharpening) technology to sharpen it to ensure the smooth dressing of the electroplated grinding wheel conduct. This dressing method needs to add coolant to reduce the temperature of the processing area, reduce the thermal deformation of the grinding wheel, and help improve the dressing accuracy. This method also avoids thermal deformation errors caused by dry grinding during the Cr12 steel block trimming method.

Specific embodiment two: present embodiment is illustrated in conjunction with Fig. 1, the rotating speed of large abrasive grain diamond grinding wheel in step one of present embodiment is 1500-2000r/min, longitudinal feed speed is 800-1200mm/min, and each lateral feed amount It is 2-5mm (the feed rate must be less than the width of the abrasive grain layer of the grinding wheel). Other implementation steps are the same as those in the first embodiment. Other implementation steps are the same as those in the first embodiment.

Embodiment 3: This embodiment is described with reference to FIG. 1 . In Step 1 of this embodiment, when the large abrasive diamond parallel grinding wheel 1 is clogged, it is sharpened with a whetstone. Other implementation steps are the same as those in the first embodiment.

Embodiment 4: This embodiment is described in conjunction with FIG. 1 . When the cup-shaped diamond roller 4 is blocked in step 2 of the embodiment, it is sharpened by online electrolytic sharpening to ensure the smooth progress of the dressing of the electroplated grinding wheel. Other implementation steps are the same as those in the first embodiment.

Embodiment 5: In step 1 or step 2 of this embodiment, a laser displacement sensor is used to measure the rotation error of the large abrasive diamond parallel grinding wheel 1, and the measurement result is accurate and accurate. Other implementation steps are the same as those in the first embodiment.

Claims (5)

1. one kind big abrasive particle skive precise dressing method; It is characterized in that said method comprising the steps of: step 1, installation big abrasive particle diamond parallel grinding wheel (1) on the precisive plane grinding machine; Square Cr12 bloom (2) is placed on the magnetic worktable; Control big abrasive particle diamond parallel grinding wheel (1) with the mode flat surface grinding of infeed grinding processing Cr12 bloom (2) through numerical control program, survey big abrasive particle skive turn error, until the turn error value less than 10 μ m;

Step 2, cup-shaped diamond roller (4) will be housed the dresser shaft clamping on anchor clamps (3); Then it is adsorbed on the lathe magnetic worktable, the Frequency Converter Control that the utilization conditioning system carries is regulated the rotating speed of cup-shaped diamond roller (4), and rotating speed is transferred 1200r-1800r/min; Through the relative motion of cup-shaped diamond roller (4) with big abrasive particle diamond parallel grinding wheel (1); Produce the wearing and tearing of diamond abrasive grain, survey big abrasive particle skive turn error, until the turn error value less than 5 μ m.

2. according to the said big abrasive particle skive precise dressing method of claim 1, it is characterized in that the rotating speed of big abrasive particle skive in the step 1 is that 1500-2000r/min, length feed speed are 800-1200mm/min, each lateral feed is 2-5mm.

3. according to claim 1 or 2 said big abrasive particle skive precise dressing methods, carry out dressing with oilstone when it is characterized in that big abrasive particle diamond parallel grinding wheel (1) stops up in the step 1.

4. according to the said big abrasive particle skive precise dressing method of claim 1, with online electrolysis it is carried out dressing when it is characterized in that cup-shaped diamond roller (4) stops up in the step 2.

5. according to the said big abrasive particle skive precise dressing method of claim 1, it is characterized in that the turn error of measuring big abrasive particle diamond parallel grinding wheel (1) in step 1 or the step 2 adopts laser displacement sensor.

Images