阅读说明：本技术 一种精密微电机轴承的外圆精超研工艺方法 (Excircle fine super-grinding process method of precision micro-motor bearing ) 是由 郝子成 王颢 魏伟 周伦文 于 2021-07-12 设计创作，主要内容包括：本发明公开了一种精密微电机轴承的外圆精超研工艺方法,包括以下步骤：S1、添加切削液；S2、粗研；S3、精研；本发明中使用水溶性切削液在外圈粗研和精研加工过程中,不会产生油雾,改善加工环境；废液产生率低,并能够循环使用,降低加工成本；本发明中,粗研步骤中可以降低轴承外圈或内圈的外圆尺寸,并在精研步骤中修复轴承外圈的外圆表面,最终得到外观无划伤有明显光亮丝路,尺寸集中度为2um,圆度≤0.3um,粗糙度≤0.05um的高精度轴承外圈。(The invention discloses an excircle fine lapping process method of a precision micro motor bearing, which comprises the following steps: s1, adding cutting fluid; s2, coarse grinding; s3, fine grinding; in the invention, water-soluble cutting fluid is used in the processing processes of rough grinding and fine grinding of the outer ring, so that oil mist is not generated, and the processing environment is improved; the waste liquid generation rate is low, and the waste liquid can be recycled, so that the processing cost is reduced; according to the invention, the size of the outer circle of the bearing outer ring or the outer circle of the bearing inner ring can be reduced in the rough grinding step, and the surface of the outer circle of the bearing outer ring is repaired in the fine grinding step, so that the high-precision bearing outer ring which is free from scratches in appearance, has an obvious bright thread path, is 2um in size concentration, is less than or equal to 0.3um in roundness and is less than or equal to 0.05um in roughness is finally obtained.)

1. The outer circle fine lapping process method of the precision micro motor bearing is characterized by comprising the following steps of:

s1, adding cutting fluid: adding the diluted water-soluble cutting fluid into a circulating cooling tank of the cylindrical superfinishing machine, and starting the cylindrical superfinishing machine to circulate the water-soluble cutting fluid;

s2, coarse grinding: clamping coarse oilstones with the mesh number of 800-1500 meshes and the granularity of 25-30 by using a tool rest of the cylindrical superfinishing machine, driving a workpiece to rotate by a guide wheel of the cylindrical superfinishing machine at the rotation speed of 1800-2000 rpm, operating a clamp frame to press the coarse oilstones on the surface of the workpiece to reduce the size of the excircle of the workpiece, and discharging water-soluble cutting fluid from a circulating cooling tank to flush the grinding area of the workpiece;

s3, fine grinding: and (4) continuously rotating the guide wheel at the same rotating speed in the step S2, continuously discharging water-soluble cutting fluid in the circulating cooling tank, continuously flushing the workpiece grinding area in the step S2, replacing the coarse oilstone on the tool rest with an essential oilstone with the mesh number of 5000-7000 and the granularity of 8-12, and operating the clamp frame to press the essential oilstone on the surface of the workpiece so as to repair the outer circular surface of the workpiece coarsely ground in the step S2.

2. The outer circle fine lapping process method of a precision micro motor bearing according to claim 1, wherein the water-soluble cutting fluid is diluted by water, and the volume ratio of the water-soluble cutting fluid to the water is 1: 5-1: 10.

3. The outer circle fine lapping process method of the precision micro motor bearing according to claim 2, wherein the water-soluble cutting fluid is diluted, uniformly stirred, kept stand in a circulating cooling tank for 30min, and the outer circle super-finishing machine is started to circulate the water-soluble cutting fluid for 5 min.

4. The outer circle fine lapping process method of the precise micro motor bearing as claimed in claim 2, wherein the water-soluble cutting fluid is composed of the following raw materials by weight percent: 3 to 6 percent of water-soluble polymerized grease, 5 to 10 percent of polyether, 17 to 25 percent of alcohol amine, 6 to 12 percent of antirust agent, 3 to 5 percent of solubilizer, 0.2 to 1 percent of settling agent and 0.3 to 1 percent of foam inhibitor.

5. The outer circle fine lapping process method of the precision micro motor bearing according to claim 1, wherein 10-15 circulation pipes aligned with the grinding area are connected to the outer circle super lapping machine, and the flow rate of the water-soluble cutting fluid in the circulation pipes is 5L/min.

6. The external circle fine lapping process method of a precision micro motor bearing according to claim 1, wherein the pressure of the coarse oilstone to the external circle of the workpiece in the step S2 is 0.15-0.2 MPa, the rotating speed of the guide wheel is 1800rpm, the mesh number of the coarse oilstone is 1000 meshes, and the grain size is 28.

7. The method for the external circle lapping process of the precision micro-motor bearing according to claim 1, wherein the pressure of the refined oilstone on the external circle of the workpiece in the step S3 is 0.05-0.1 MPa, the rotating speed of the guide wheel is 1800rpm, the mesh number of the coarse oilstone is 6000 meshes, and the grain size is 10.

8. The cylindrical lapping process of a precision micro motor bearing according to claim 1, wherein the coarse oilstone and the essential oilstone are both made of CBN material.

9. The method for performing the cylindrical lapping process of the bearing of the precision micro-motor according to claim 1, wherein the workpiece lapped by the step of S3 has no scratch on the appearance, obvious bright filament paths, a size concentration of 2um, a roundness of 0.3um or less, and a roughness of 0.05um or less.

Technical Field

The invention belongs to the technical field of bearing grinding, and relates to an excircle fine lapping process method of a precision micro-motor bearing.

Background

The micromotor bearing mainly comprises an outer ring, an inner ring, a rolling body, a retainer, a dust cover, grease and the like, wherein the outer circles of the outer ring and the inner ring need to be ground, the existing grinding basically adopts a non-water-soluble oil agent based on mineral oil, and the non-water-soluble oil agent has good lubricity but has the defects of flammability, oil mist generation, waste liquid treatment, high cost and the like; a small amount of water-soluble grinding fluid for bearing processing still exists in the current market, but the size precision and the roughness of the bearing manufactured by adopting the processing technology of the water-soluble grinding fluid do not reach the standard, and the processing performance requirement of the micro-motor bearing cannot be met.

Disclosure of Invention

Aiming at the problems, the invention provides an excircle fine lapping process method of a precision micro motor bearing, which well solves the problems of high processing cost, oil mist waste liquid generation and substandard processing precision in the prior art.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: an excircle fine lapping process method of a precision micro-motor bearing comprises the following steps:

s1, adding cutting fluid: adding the diluted water-soluble cutting fluid into a circulating cooling tank of the cylindrical superfinishing machine, and starting the cylindrical superfinishing machine to circulate the water-soluble cutting fluid;

s2, coarse grinding: clamping coarse oilstones with the mesh number of 800-1500 meshes and the granularity of 25-30 by using a tool rest of the cylindrical superfinishing machine, driving a workpiece to rotate by a guide wheel of the cylindrical superfinishing machine at the rotation speed of 1800-2000 rpm, operating a clamp frame to press the coarse oilstones on the surface of the workpiece to reduce the size of the excircle of the workpiece, and discharging water-soluble cutting fluid from a circulating cooling tank to flush the grinding area of the workpiece;

s3, fine grinding: and (4) continuously rotating the guide wheel at the same rotating speed in the step S2, continuously discharging water-soluble cutting fluid in the circulating cooling tank, continuously flushing the workpiece grinding area in the step S2, replacing the coarse oilstone on the tool rest with an essential oilstone with the mesh number of 5000-7000 and the granularity of 8-12, and operating the clamp frame to press the essential oilstone on the surface of the workpiece so as to repair the outer circular surface of the workpiece coarsely ground in the step S2.

Furthermore, the water-soluble cutting fluid is diluted by water, and the volume ratio of the water-soluble cutting fluid to the water is 1: 5-1: 10.

Further, the water-soluble cutting fluid is diluted, uniformly stirred, placed in a circulating cooling box for 30min, and the cylindrical superfinishing machine is started to circulate the water-soluble cutting fluid for 5 min.

Further, the water-soluble cutting fluid is prepared from the following raw materials in percentage by weight: 3 to 6 percent of water-soluble polymerized grease, 5 to 10 percent of polyether, 17 to 25 percent of alcohol amine, 6 to 12 percent of antirust agent, 3 to 5 percent of solubilizer, 0.2 to 1 percent of settling agent and 0.3 to 1 percent of foam inhibitor.

Furthermore, 10-15 circulation pipes aligned with the grinding areas are communicated with the outer circle superfinishing machine, and the flow rate of the water-soluble cutting fluid in the circulation pipes is 5L/min.

Further, in the step S2, the pressure of the coarse oilstone on the outer circle of the workpiece is 0.15 to 0.2MPa, the rotating speed of the guide wheel is 1800rpm, the mesh number of the coarse oilstone is 1000 meshes, and the grain size is 28.

Further, in the step S3, the pressure of the refined oilstone on the excircle of the workpiece is 0.05-0.1 MPa, the rotating speed of the guide wheel is 1800rpm, the mesh number of the coarse oilstone is 6000 meshes, and the granularity is 10.

Further, both the crude oil stone and the essential oil stone are made of CBN materials.

Furthermore, the workpiece finely ground in the step S3 has no scratch on the appearance and obvious bright filament paths, the size concentration is 2um, the roundness is less than or equal to 0.3um, and the roughness is less than or equal to 0.05 um.

Compared with the prior art, the invention has the following beneficial effects:

in the invention, water-soluble cutting fluid is used in the processing processes of rough grinding and fine grinding of the outer ring, so that oil mist is not generated, and the processing environment is improved; the waste liquid has low generation rate, can be recycled, and reduces the processing cost.

According to the invention, the size of the outer circle of the bearing outer ring or the outer circle of the bearing inner ring can be reduced in the rough grinding step, and the surface of the outer circle of the bearing outer ring is repaired in the fine grinding step, so that the high-precision bearing outer ring which is free from scratches in appearance, has an obvious bright thread path, is 2um in size concentration, is less than or equal to 0.3um in roundness and is less than or equal to 0.05um in roughness is finally obtained.

Drawings

FIG. 1 is an appearance view of a surface of a workpiece machined with a water-insoluble finish cutting fluid according to example 2 of the present invention;

FIG. 2 is an appearance view of a surface of a workpiece machined with a water-soluble cutting fluid according to example 2 of the present invention;

FIG. 3 is a comparison of the surface appearance of a workpiece processed by a water-insoluble oil cutting fluid and a water-soluble cutting fluid in example 2 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The invention provides an excircle fine lapping process method of a precision micro-motor bearing, which comprises the following steps:

s1, adding cutting fluid: adding the diluted water-soluble cutting fluid into a circulating cooling tank of the cylindrical superfinishing machine, and starting the cylindrical superfinishing machine to circulate the water-soluble cutting fluid;

s2, coarse grinding: clamping coarse oilstones with the mesh number of 800-1500 meshes and the granularity of 25-30 by using a tool rest of the cylindrical superfinishing machine, driving a workpiece to rotate by a guide wheel of the cylindrical superfinishing machine at the rotation speed of 1800-2000 rpm, operating a clamp frame to press the coarse oilstones on the surface of the workpiece to reduce the size of the excircle of the workpiece, and discharging water-soluble cutting fluid from a circulating cooling tank to flush the grinding area of the workpiece;

s3, fine grinding: and (4) continuously rotating the guide wheel at the same rotating speed in the step S2, continuously discharging water-soluble cutting fluid in the circulating cooling tank, continuously flushing the workpiece grinding area in the step S2, replacing the coarse oilstone on the tool rest with an essential oilstone with the mesh number of 5000-7000 and the granularity of 8-12, and operating the clamp frame to press the essential oilstone on the surface of the workpiece so as to repair the outer circular surface of the workpiece coarsely ground in the step S2.

In the embodiment, the workpiece is provided with a bearing outer ring and an inner ring, the outer diameter of the outer ring is phi 8mm, the inner diameter of the outer ring is phi 6.8mm, the curvature of the groove is R0.44mm, and the width dimension of the groove is 4 mm; the inner diameter of the inner ring 2 is phi 3mm, the outer diameter is phi 4.1mm, and the width is 4 mm.

Preferably, the water-soluble cutting fluid is diluted, uniformly stirred and kept stand in a circulating cooling box for 30min, so that the water-soluble cutting fluid is uniformly mixed, and impurities in the water-soluble cutting fluid are precipitated at the bottom of the circulating cooling box during standing; starting the cylindrical superfinishing machine to circulate the water-soluble cutting fluid for 5min, and discharging impurities existing in the original pipeline; the grinding area is prevented from entering, and the roughness and the roundness of the excircle of the workpiece are reduced.

Preferably, 10-15 circulation pipes aligned with the grinding areas are communicated with the outer circle superfinishing machine, and the flow rate of the water-soluble cutting fluid in the circulation pipes is 5L/min; the water-soluble cutting fluid is ensured to have enough range to cover the grinding area of the workpiece, and has enough scouring force to scour away the chips generated in the grinding area.

Preferably, the crude oilstone and the essential oilstone are both made of CBN materials, so that the service lives of the crude oilstone and the essential oilstone are prolonged.

Preferably, the water-soluble cutting fluid is diluted by water, and the volume ratio of the water-soluble cutting fluid to the water is 1: 5-1: 10; the water-soluble cutting fluid is prepared from the following raw materials in percentage by weight: 3 to 6 percent of water-soluble polymerized grease, 5 to 10 percent of polyether, 17 to 25 percent of alcohol amine, 6 to 12 percent of antirust agent, 3 to 5 percent of solubilizer, 0.2 to 1 percent of settling agent and 0.3 to 1 percent of foam inhibitor. The diluted water-soluble cutting fluid is milk white, the concentration of the refractometer diluent is 6-8%, the pH value is 9.0-9.5, and the water-soluble cutting fluid has good heat dispersion, sedimentation performance, cleaning performance and lubricating performance.

Through the processing of the technical scheme, the workpiece finely ground in the step S3 has no scratch on appearance, obvious bright filament paths, size concentration of 2um, roundness of less than or equal to 0.3um and roughness of less than or equal to 0.05 um.

Four groups of corrosion tests are carried out on the workpiece processed by the technical scheme, the corrosion test results are shown in the following table 1, and the test conditions are as follows:

test conditions 1: 20 ℃/50% relative humidity;

test conditions 2: 38.5 ℃/50% relative humidity;

test conditions 3: 20 ℃/90% relative humidity;

test conditions 4: 8.5 ℃/90% relative humidity;

table 1:

as can be seen from Table 1, under the test conditions of different temperatures and humidity, the surface of the bearing outer ring or the bearing inner ring can reach 48h of rust prevention test, which is far beyond the flow time of the production line, so that the rust prevention requirement can be met in the normal processing flow, and the rust prevention effect is good.

Example 2

The invention provides an excircle fine lapping process method of a precision micro-motor bearing, which comprises the following steps:

s1, adding cutting fluid: adding the diluted water-soluble cutting fluid into a circulating cooling tank of the cylindrical superfinishing machine, and starting the cylindrical superfinishing machine to circulate the water-soluble cutting fluid;

s2, coarse grinding: clamping coarse oilstone with the mesh number of 1000 and the granularity of 28 by using a tool rest of the external cylindrical superfinishing machine, driving a workpiece to rotate by a guide wheel of the external cylindrical superfinishing machine at the rotation speed of 1800rpm, operating the clamp frame to press the coarse oilstone on the surface of the workpiece at the pressure of 0.15-0.2 MPa so as to reduce the size of the external circle of the workpiece, and discharging water-soluble cutting fluid from a circulating cooling tank to flush the grinding area of the workpiece;

s3, fine grinding: and (4) continuously rotating the guide wheel at the same rotating speed in the step S2, continuously discharging water-soluble cutting fluid from the circulating cooling tank, continuously flushing the workpiece grinding area in the step S2, replacing the coarse oilstone on the tool rest with an oilstone with the mesh number of 6000 and the granularity of 10, and operating the tool rest to enable the oilstone to be pressed on the surface of the workpiece at the pressure of 0.05-0.1 MPa so as to repair the outer circle surface of the workpiece coarsely ground in the step S2.

In the embodiment, the workpiece is provided with a bearing outer ring and an inner ring, the outer diameter of the outer ring is phi 8mm, the inner diameter of the outer ring is phi 6.8mm, the curvature of the groove is R0.44mm, and the width dimension of the groove is 4 mm; the inner diameter of the inner ring 2 is phi 3mm, the outer diameter is phi 4.1mm, and the width is 4 mm.

Through the processing of the technical scheme, the workpiece finely ground in the step S3 has no scratch on appearance, obvious bright filament paths, size concentration of 2um, roundness of less than or equal to 0.3um and roughness of less than or equal to 0.05 um.

In the implementation, the same processing parameters are adopted, the water-soluble cutting fluid is replaced by the water-insoluble oil cutting fluid, and the workpiece is processed for 10 ten thousand times; the comparison items and results are shown in table 2 below, comparing the workpiece processed with the processing parameters of the present embodiment for 10 ten thousand times:

table 2:

as can be seen from table 2 and fig. 1, 2 and 3, the oilstone requires less pressure and can have deeper processing depth when the water-soluble cutting fluid is used for processing, and the roughness average values of 10 ten thousand workpieces are 0.065um and 0.050um respectively, so that the surface processing quality and the surface roughness are obviously improved by using the water-soluble cutting fluid.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.