阅读说明：本技术 一种陶瓷结合剂cbn砂轮的循环在线磨削与修整方法 (Cyclic online grinding and finishing method for ceramic bond CBN grinding wheel ) 是由 郑师光 吕升东 刘宏伟 李涛 张天罡 于 2019-08-19 设计创作，主要内容包括：本发明公开一种陶瓷结合剂CBN砂轮的循环在线磨削与修整方法,转盘上设置双向电机,双向电机的两端固定CBN砂轮,一端的CBN砂轮加工工件,另外一端的CBN砂轮被修整；当加工用砂轮需要修整时,转动转盘将用于加工的CBN砂轮与被修整的CBN砂轮进行对换；砂轮修整的方法是：在磨削部位引入的冷却液混合有修整磨料,修整磨料在外部径向磨削压力和冷却液的带动作用下能够很好地嵌入CBN砂轮的结合剂中,使结合剂破碎和磨平的CBN磨料颗粒脱落,实现CBN砂轮的在线修整。本发明是能够很好地实现陶瓷结合剂CBN砂轮的在线修整,具有修整效率高、消耗小,修整后出刃高度一致性好,修整均匀,是一种能够循环在线磨削与修整的方法。(The invention discloses a circulating online grinding and finishing method of a ceramic bond CBN grinding wheel, wherein a bidirectional motor is arranged on a turntable, the two ends of the bidirectional motor are fixedly provided with the CBN grinding wheel, the CBN grinding wheel at one end is used for processing a workpiece, and the CBN grinding wheel at the other end is finished; when the grinding wheel for machining needs to be dressed, the rotary table is rotated to exchange the CBN grinding wheel for machining with the dressed CBN grinding wheel; the method for dressing the grinding wheel comprises the following steps: the coolant introduced into the grinding part is mixed with the dressing abrasive, and the dressing abrasive can be well embedded into the bonding agent of the CBN grinding wheel under the driving action of the external radial grinding pressure and the coolant, so that the CBN abrasive grains crushed and ground flat by the bonding agent fall off, and the online dressing of the CBN grinding wheel is realized. The method can well realize the online finishing of the ceramic bond CBN grinding wheel, has the advantages of high finishing efficiency, low consumption, good consistency of the height of the finished edge and uniform finishing, and is a method capable of circularly grinding and finishing online.)

1. A method for circularly grinding and dressing a ceramic bond CBN grinding wheel on line is characterized by comprising the following steps: a bidirectional motor is arranged on the turntable, CBN grinding wheels are fixed at two ends of the bidirectional motor, the CBN grinding wheel at one end is used for processing a workpiece, and the CBN grinding wheel at the other end is used for finishing; when the grinding wheel for machining needs to be dressed, the rotary table is rotated to exchange the CBN grinding wheel for machining with the dressed CBN grinding wheel; the method for dressing the grinding wheel comprises the following steps: the coolant introduced into the grinding part is mixed with the dressing abrasive, and the dressing abrasive can be well embedded into the bonding agent of the CBN grinding wheel under the driving action of the external radial grinding pressure and the coolant, so that the CBN abrasive grains crushed and ground flat by the bonding agent fall off, and the online dressing of the CBN grinding wheel is realized.

2. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as claimed in claim 1, characterized in that: the hardness of the finishing grinding material is lower than the abrasive particle hardness of the CBN grinding wheel, and the hardness of the finishing grinding material is higher than that of the ceramic bond; therefore, the bonding agent of the CBN grinding wheel can be broken, and the physical and mechanical damage to the abrasive particles in the CBN grinding wheel can be avoided.

3. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as claimed in claim 1, characterized in that: the material of the finishing abrasive can be at least one of corundum and silicon carbide.

4. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as set forth in claim 3, characterized in that: the silicon carbide may be selected from green silicon carbide.

5. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as claimed in claim 1, characterized in that: in order to ensure the dressing efficiency, under the mechanical extrusion action of a dresser and a dressing abrasive, a bonding agent of the CBN grinding wheel is quickly crushed to expose a new cutting edge, and the granularity of the dressing abrasive is 1-3 granularity levels coarser than that of the CBN.

6. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as claimed in claim 1, characterized in that: the grinding contact area of the CBN grinding wheel is 10-100mm2, and the thickness of the grinding layer of the grinding wheel is 1-10 mm.

7. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as claimed in claim 1, characterized in that: the granularity of the CBN grinding wheel is 80# to 220#, and the granularity of the dressing abrasive is 60# to 600 #.

8. The method of cyclically grinding and dressing a vitrified bond CBN grinding wheel as claimed in claim 1, characterized in that: the linear speed of the CBN grinding wheel is 20-40m/s, the linear speed of the dresser is 1-10m/s, and the feeding speed of the workpiece is 0.2-0.6 mm/min.

Technical Field

the invention relates to a method for dressing a grinding wheel, in particular to a circulating grinding and online dressing method for a CBN grinding wheel, and belongs to the field of precision machining.

Background

The CBN grinding wheel has excellent grinding performance and can be widely applied to the field of processing of materials difficult to process.

In the machining of a workpiece by a CBN grinding wheel numerical control grinding machine, the forming of the workpiece depends on the shape of the grinding wheel, abrasive particles can become dull and not sharp gradually after the grinding wheel is used for a period of time, and different degrees of abrasion occur in a grinding state, so that the effective trimming of the grinding wheel due to unqualified workpiece quality and even burning damage after the workpiece is ground is a precondition for ensuring high-quality machining. The grinding wheel should be timely shaped, otherwise the workpiece may have a small error, and even worse, the workpiece may be a waste product.

currently, the following methods are mainly adopted for dressing of grinding wheels:

1. Diamond pen dressing method. The grinding wheel is used for dressing the resin bond superhard abrasive grinding wheel, and the grinding wheel rotates at a low speed during dressing; otherwise, the finishing effect is not good, and the diamond pen is worn quickly. The grinding wheel dressed by the method has smooth surface, poor grinding performance and low shape and size precision, so the method is only used under the condition of no other dressing conditions. The method needs to specially arrange a feeding base on a grinding machine, a grinding wheel dressing frame is arranged on the feeding base, a diamond pen is arranged on the grinding wheel dressing frame, when the grinding wheel needs to be dressed, the relative positions of the feeding base and the relative positions of the grinding wheel dressing frame and the feeding base need to be adjusted, the adjustment is relatively complex, the dressing effect is unstable, and the universality is poor.

2. Grinding and shaping. The method can also be used for dressing, and is a commonly used dressing method. The CBN grinding wheel can be dressed by silicon carbide, corundum and oilstone, and can also be dressed by a power-driven diamond, silicon carbide or corundum grinding wheel. When the common abrasive grain grinding wheel is used as a dressing wheel, the dressing precision is slightly poor, the grinding performance of the dressing wheel is good, and the dressing wheel is suitable for dressing the grinding wheel with low profile precision requirement or the grinding capacity requirement. When the diamond grinding wheel is used as a dressing wheel, the shaping precision is good, but the grinding capability of the dressing wheel is poor, so the diamond grinding wheel is only used for dressing the grinding wheel with higher requirement on the profile precision. In order to improve the grinding capacity, the grinding wheel and the grinding wheel can be used together, namely the grinding wheel and the grinding wheel are shaped by a diamond grinding wheel and then are dressed by a common abrasive grinding wheel. In addition, when the method is used for trimming, the CBN grinding wheel needs to be disassembled and is remounted on an external grinding machine or a special trimming machine for trimming, and the online trimming cannot be realized. In summary, the existing CBN grinding wheel has a complex dressing process and cannot realize online dressing.

3. And (3) a mild steel grinding and finishing method. The soft steel is used for grinding and shaping, and meanwhile, the sharpening can be performed. Because the abrasive particles fall off more during shaping, the method is not suitable for trimming the grinding wheel with higher requirement on the profile precision. The soft steel grinding method includes single roller method and double roller method, and has two soft steel rollers in the same rotation direction but different rotation speed. If the linear speed of the dressed grinding wheel is Vsd, the linear speed of one mild steel roller is Vsd + V, and the other is Vsd-V. Therefore, two dressing forces with equal magnitude and opposite directions exist in the tangential direction of the dressed grinding wheel. Therefore, the dressed grinding wheel can not generate additional interference torque, the shaping process can be ensured to be stable, and the shaping quality is improved.

Disclosure of Invention

The invention aims to reduce invalid processing time and improve grinding precision, and provides a circulating grinding online finishing method for a CBN grinding wheel, so that the problems that the grinding wheel is complicated in finishing process and cannot be finished online are solved.

in order to achieve the purpose, the technical scheme of the invention is realized by determining the dressing time of the CBN grinding wheel by judging the working state of the grinding wheel through external online measurement and data processing of a workpiece and determining the dressing curve of the grinding wheel by using a grinding wheel dresser, and the adopted technical scheme comprises the following steps:

A method for circularly grinding and dressing a ceramic bond CBN grinding wheel on line comprises the steps that a bidirectional motor is arranged on a rotary table, the two ends of the bidirectional motor are fixedly provided with the CBN grinding wheel, the CBN grinding wheel at one end is used for machining a workpiece, and the CBN grinding wheel at the other end is dressed; when the grinding wheel for machining needs to be dressed, the rotary table is rotated to exchange the CBN grinding wheel for machining with the dressed CBN grinding wheel; the method for dressing the grinding wheel comprises the following steps: the coolant introduced into the grinding part is mixed with the dressing abrasive, and the dressing abrasive can be well embedded into the bonding agent of the CBN grinding wheel under the driving action of the external radial grinding pressure and the coolant, so that the CBN abrasive grains crushed and ground flat by the bonding agent fall off, and the online dressing of the CBN grinding wheel is realized. The coolant may be a commercially available grinding fluid.

The hardness of the finishing grinding material is lower than the abrasive particle hardness of the CBN grinding wheel, and the hardness of the finishing grinding material is higher than that of the ceramic bond; therefore, the bonding agent of the CBN grinding wheel can be broken, and the physical and mechanical damage to the abrasive particles in the CBN grinding wheel can be avoided.

The material of the finishing abrasive can be at least one of corundum and silicon carbide.

The silicon carbide may be selected from green silicon carbide.

In order to ensure the dressing efficiency, under the mechanical extrusion action of a dresser and a dressing abrasive, a bonding agent of the CBN grinding wheel is quickly crushed to expose a new cutting edge, and the granularity of the dressing abrasive is 1-3 granularity levels coarser than that of the CBN.

the grinding contact area of the CBN grinding wheel is 10-100mm2, and the thickness of the grinding layer of the grinding wheel is 1-10 mm.

The granularity of the CBN grinding wheel is 80# to 220#, and the granularity of the dressing abrasive is 60# to 600 #.

The linear speed of the CBN grinding wheel is 20-40m/s, the linear speed of the dresser is 1-10m/s, and the feeding speed of the workpiece is 0.2-0.6 mm/min.

The method can well realize the online finishing of the ceramic bond CBN grinding wheel, has the advantages of high finishing efficiency, low consumption, good consistency of the height of the finished edge and uniform finishing, and is a method capable of circularly grinding and finishing online.

Drawings

FIG. 1 is a schematic diagram of the principles of the present invention;

FIG. 2 is a schematic view of the trimming principle;

In the figure, 1 is a processing motor, 2 is a workpiece, 3 is a processing grinding wheel, 4 is a bidirectional motor, 5 is a grinding wheel to be trimmed, 6 is a trimmer, 7 is a trimming motor, 8 is a processing seat slide rail, 9 is a rotary table, and 10 is a trimming seat slide rail.

Detailed Description

The invention is described in detail with reference to the accompanying drawings, and a schematic diagram of a main process of the dressing method of the invention is shown in fig. 1, wherein a part of a workpiece 2 (driven by a machining motor 1) is ground by a machining grinding wheel 3 on the left side, when the grinding wheel needs to be dressed, the rotating turntable 9 is fixed after the machining grinding wheel 3 and a dressed grinding wheel 5 are switched by the rotating turntable 9, so that the right dressed grinding wheel 5 rotates to the left side to continue working, the machining grinding wheel 3 on the left side rotates to the right side and is dressed by a dresser 6 driven by a dressing motor 7, and a cooling liquid and a dressing abrasive mixture are added; the reciprocating operation can be performed circularly. The rotating method of the turntable can adopt a mechanical method, such as a method that a gear driven by a motor is meshed with a rotating gear on a turntable shaft, a method that a chain driven by the motor is meshed with the rotating gear on the turntable shaft, and the like which are generally adopted; the processing motor is arranged on the processing seat, the processing seat can move along the processing seat slide rail so as to be convenient for the turntable to rotate without interference, the processing seat can move by adopting a lead screw driven by the motor to be matched with a nut seat on the processing seat, and when the connecting end of the lead screw and the motor is fixed, the rotation of the lead screw can drive the processing seat to move back and forth; by the same token, the trimming seat can move on the trimming slide rail; after the dressing liquid and the dressing abrasive are mixed in advance, the dressing liquid and the dressing abrasive are added between the dresser and the dressing gear through a circulating water system.