CN-117900953-B - Grinding wheel dressing method for machining cycloidal gear by using worm grinding wheel gear grinding machine

CN117900953BCN 117900953 BCN117900953 BCN 117900953BCN-117900953-B

Abstract

The invention discloses a grinding wheel dressing method for machining cycloidal gears by using a worm grinding wheel gear grinding machine, which is characterized in that the worm grinding wheel gear grinding machine integrating the machining function of the cycloidal gears and the grinding wheel dressing function is used for realizing quick and accurate dressing of grinding wheels. The worm grinding wheel gear grinding machine capable of adjusting the central axis swing angle of the trimmer is used, the motion freedom degree of the trimmer when the grinding wheel is trimmed is increased, the influence caused by tooth profile change of the grinding wheel is reduced, errors generated when the grinding wheel is trimmed are controlled, the working stability of a machine tool is improved, a contact type vibration sensor is arranged on the grinding wheel, the machine tool is enabled to automatically adjust the centering of the trimmer through sensing vibration data, the manual operation flow is simplified, the trimming precision is improved, the working time is saved, the trimmer is not needed to be centered again after the first centering is completed, the trimming efficiency is improved, and the rough machining stage can be enabled to quickly remove the surplus of the grinding wheel while the finishing stage can keep good surface morphology of the grinding wheel through distinguishing the two-stage machining process of the trimming grinding wheel of the trimmer.

Inventors

JI SHUTING
Yuan Erhao
ZHANG YUEMING

Assignees

北京工业大学

Dates

Publication Date: 20260505
Application Date: 20231227

Claims (5)

1. A grinding wheel dressing method for machining cycloidal gears by using worm grinding wheel gear grinding machine is characterized by comprising the worm grinding wheel gear grinding machine integrating a cycloidal gear machining function and a grinding wheel dressing function into a whole, enabling a machine tool to convert two working states of grinding teeth and dressing grinding wheels, using the worm grinding wheel gear grinding machine capable of adjusting the swing angle of the central axis of a dressing machine, increasing the freedom degree of movement of the dressing machine when dressing the grinding wheels, reducing the influence of the grinding wheel on machining cycloidal gears caused by reduction of the outer diameter of the grinding wheels due to repeated dressing, separation of tooth shapes of the grinding wheels from theoretical tooth surfaces conjugated with tooth shapes of the cycloidal gears, controlling errors generated when dressing the grinding wheels, collecting vibration data of the grinding wheels through a contact vibration sensor arranged on a grinding wheel mounting frame, guiding the machine tool to finish centering, accurately positioning the initial machining position of a second wire head in the machining process without dividing centering again through calculation, distinguishing two machining stages in the dressing grinding wheel process, and rapidly removing the allowance of the grinding wheels at the rough machining stage.
2. The grinding wheel dressing method for machining cycloidal gears by using worm grinding wheels according to claim 1, wherein the CRT turntable (2) is mounted on a machine tool base (1) and can rotate around a CRT axis, a dresser mounting frame (5) and a workpiece turntable (3) are mounted on the CRT turntable (2), a dresser rotating motor (12) is mounted on the dresser mounting frame (5), an output shaft of the dresser rotating motor (12) is a dresser mounting expansion shaft (20), a dresser (11) is sleeved on the dresser mounting expansion shaft (20) and is fixed by a dresser fixing screw (17), the dresser (11) is driven by the dresser rotating motor (12), a workpiece (4) is mounted on the workpiece turntable (3) and can rotate around the CRT axis C axis, the working positions of the dresser mounting frame (5) and the workpiece turntable (3) can be adjusted by rotating the CRT turntable (2) so as to achieve conversion of the quick-speed adjusting machine in two working states, and when the worm grinding wheel is dressed by the worm grinding machine, the large CRT (2) is subjected to dressing, the grinding wheel (10) is carried out by the dresser.
3. A grinding wheel dressing method for machining cycloidal gears by using worm grinding wheels according to claim 2, wherein the dresser mounting frame (5) can rotate along with the axis C2 of the dresser mounting frame, the rotation and swinging of the dresser mounting frame (5) around the axis C2 are equivalent to the increase of the freedom degree of movement of the dresser (11) when a machine tool is used for dressing grinding wheels, and the central axis B2 of the dresser (11) is enabled to obtain a swinging angle in a horizontal plane during dressing, which is equivalent to the adjustment of the pressure angle of the tooth shape of the grinding wheels.
4. A grinding wheel dressing method for machining cycloidal gears using a worm grinding wheel gear grinding machine according to claim 3, wherein the contact vibration sensor (18) is mounted on the grinding wheel mounting frame (6), and before the start of the tool setting, the grinding wheel end face (16) is aligned with the center end section of the dresser (11) by the movement of the Y axis and the Z axis, and the geometric center point of the grinding wheel end face (16) is positioned at the same level as the axis of the dresser; the dresser (11) rotates positively around the spindle B2, the grinding wheel (10) moves only in the X-axis negative direction, the spindle B is locked and not rotated, the feed rate of the X guide rail (8) is reduced when the grinding wheel (10) approaches the dresser (11) and approaches the dresser (11) in the X-axis negative direction, the vibration is sensed by a contact vibration sensor (18) on the grinding wheel (10) when the grinding wheel (10) contacts the dresser (11), the machine tool records the X-axis position and compares the X-axis position with the sum of the outer circle radius of the grinding wheel (10) and the outer circle radius of the dresser (11), if the position is not in the tooth surface tooth profile valley, the grinding wheel (10) is retracted in the X-axis positive direction by the low feed rate until the grinding wheel exits, then the spindle B is rotated for a certain angle, the step is executed again, if the position is in the tooth surface tooth profile valley, the Y-axis position is recorded, then the grinding wheel (10) moves in the Y-axis negative direction by the low feed rate, there are two contact states, namely, if the contact vibration sensor (18) senses vibration all the time and vibration is increased along with the movement of the grinding wheel (10), the grinding wheel (10) moves forward along the Y guide rail (7) towards the Y axis at a low feeding multiplying power, until the contact vibration sensor (18) senses vibration again, the movement is stopped, the Y axis position is recorded, the midpoint of the two positions is the centering position of the trimming at the time, if the contact vibration sensor (18) stops vibrating immediately along the Y guide rail (7) towards the negative Y axis direction at a low feeding multiplying power, and when the contact vibration sensor (18) detects vibration again at a distance towards the negative Y axis direction, the midpoint of the two positions is recorded, namely the centering position of the trimming at the time.
5. The grinding wheel dressing method for machining cycloidal gears using a worm grinding wheel gear grinding machine according to claim 4, wherein the process of dressing the grinding wheel is divided into two machining stages in order to reduce errors caused by insufficient centering and indexing; for the rough machining stage, the grinding wheel (10) is fed with a grinding amount X 1 in the negative X-axis direction, the grinding wheel (10) is spirally moved in the positive Y-axis direction, namely, according to the designed spiral line parameters, the grinding wheel (10) rotates positively around the B-axis and simultaneously moves positively around the Y-axis, the contact position of the dresser (11) and the grinding wheel (10) is moved from the grinding wheel end face (16) to the grinding wheel end start face (15), then, the grinding wheel (10) is fed with a grinding amount X 1 in the negative X-axis direction, the grinding wheel (10) is spirally moved in the negative Y-axis direction, namely, according to the designed spiral line parameters, the grinding wheel rotates negatively around the B-axis and simultaneously moves negatively around the Y-axis, the contact position of the dresser (11) and the grinding wheel (10) is moved from the grinding wheel end face (15) to the grinding wheel end face (16), the rough machining stage is a process, the rough machining stage is performed in a reciprocating motion mode, the rough grinding stage is performed for a certain number of times, the grinding is performed through the rough machining stage until most of the allowance is removed, namely, the rough machining stage is completed, the grinding wheel (10) is completely withdrawn from the grinding cutter (10) to the positive grinding cutter (10) in the positive cutter) in the direction, the positive cutter direction is withdrawn from the position of the grinding cutter (10), the grinding wheel (10) carries out rotary indexing; the grinding wheel (10) rotates around the B axis of the main shaft clockwise, namely around the B axis in the positive direction by 2pi/n radian, namely the initial processing position of the second thread end, and centering is not needed again; then, the grinding wheel (10) returns to the first thread end processing position again, at the moment, the grinding wheel (10) is fed by a grinding amount X 2 ,x 2 <x 1 towards the negative direction of the X axis, and the grinding wheel (10) performs spiral motion along the positive direction of the Y axis, namely, according to the designed spiral line parameters, the grinding wheel (10) rotates positively around the B axis and moves positively towards the Y axis, and the contact position of the trimmer (11) and the grinding wheel (10) moves from the end face (16) of the thread end of the grinding wheel to the start end face (15) of the thread end of the grinding wheel; then, the grinding wheel withdraws the cutter towards the positive direction of the X axis until the cutter surface of the trimmer (11) completely withdraws from the tooth surface of the grinding wheel (10), the grinding wheel (10) carries out spiral motion along the negative direction of the Y axis, namely, the grinding wheel (10) rotates around the negative direction of the B axis and moves towards the negative direction of the Y axis at the same time and returns to the position before machining, the process is a process of a finishing stage, the finishing process is repeated for a certain number of times until the allowance of the finishing stage is completely removed, the finishing of the thread is completed, the motion mode of the finishing stage is unidirectional motion and unidirectional grinding, after the first thread is finished, the grinding wheel rotates and indexes, the second thread is finished until all thread is finished, the roughness of the tooth surface of the machined cycloid gear needs to reach Ra0.4mu m after finishing the grinding wheel, the finishing process is finished, otherwise, the grinding wheel needs to be re-ground and finished again, until the requirements are met.

Description

Grinding wheel dressing method for machining cycloidal gear by using worm grinding wheel gear grinding machine Technical Field The invention discloses a grinding wheel dressing method for machining cycloidal gears by using a worm grinding wheel gear grinding machine, which is characterized in that the grinding wheel dressing machine is capable of adjusting the swing angle of the central axis of a dresser, reducing the influence of the grinding wheel on the reduction of the outer diameter caused by repeated dressing, the deviation of the tooth surface of the grinding wheel from the theoretical tooth surface conjugated with the tooth surface of the cycloidal gears, controlling the error generated during dressing the grinding wheel, improving the meshing characteristic during machining the cycloidal gears by combining a cutter setting method of a contact vibration sensor, improving the cutter setting speed and accuracy of the worm grinding wheel gear grinding machine, dressing the grinding wheel in a grading manner, and ensuring the accuracy of the tooth shape of the grinding wheel through two machining processes of rough machining and finish machining. The invention belongs to the field of grinding wheel dressing of worm grinding wheel gear grinding machines in the field of precision manufacturing. Background The cycloidal gear with high transmission precision, high transmission efficiency, large reduction ratio, compact structure and long service life is an important component in the transmission part of the electromechanical system of the robot and the like, and the processing problem of the cycloidal gear is always the focus of research of all parties. With the rapid development of industry, various industries have put more urgent demands on the precision and processing efficiency of cycloidal gears, and tooth grinding is the only necessary method. For the cycloidal gear which bears the function of precise transmission, generating grinding is a high-quality precise machining method with extremely high cost performance, and the production efficiency is greatly improved by forming complex molded surfaces at one time. However, in the processing flow of generating method gear grinding, after the grinding wheel interacts with the surface of the cycloidal gear for a period of time, the grinding wheel abrasive particles lose edges and angles and are gradually passivated, and grinding residues can remain in irregular holes on the surface of the grinding wheel, so that the surface sawness of the grinding wheel can be influenced, the whole cutting force of the grinding wheel is reduced, the grinding effect on a workpiece is also influenced, and a series of problems such as slipping, processing noise, scratch lines, processing failure and the like can occur during the process of grinding the cycloidal gear. In order to ensure the sharpness and shape accuracy of the surface of the grinding wheel, the grinding wheel needs to be trimmed regularly, so that the trimming of the grinding wheel with high efficiency and high accuracy can ensure the accuracy of a machined part, the production efficiency of a machine tool is improved, and the grinding wheel trimming method on the fixed worm grinding wheel gear grinding machine is an important direction focusing attention of domestic and foreign scholars and manufacturers. The existing grinding wheel dressing methods comprise turning dressing, rolling dressing, diamond roller dressing, laser dressing, ultrasonic vibration dressing, electric spark dressing and the like. The turning dressing method is to use a diamond pen as a cutter to turn the grinding wheel, however, the nib of the diamond pen has no dressing effect and has small contact surface with the grinding wheel, so that the processing efficiency is reduced, the rolling dressing method is to use a hard alloy disc and a group of rollers sleeved by a wavy white iron disc or a quenched steel sheet with grooves to finish the grinding wheel in rolling and extrusion, the method is suitable for finishing a rough grinding wheel and is not suitable for finishing a high-precision grinding wheel, and the diamond roller finishing is to use the relative movement of rotation between the diamond roller and the grinding wheel to remove the fragments and residual binding agent on the surface of the grinding wheel, so that the dressing time is shorter and the method is suitable for finishing the grinding wheel on a worm grinding wheel gear grinding machine. In addition, laser trimming, ultrasonic vibration trimming, electric spark trimming and the like belong to the field of special trimming, the application cost is higher in small and medium-sized factories, the installation condition is severe, and the effective use of a large area is difficult to obtain at present. For a common worm grinding wheel gear grinding machine, the outer diameter of the grinding wheel is inevitably reduced, the lead angle of the thread end of the grinding whee