阅读说明：本技术 一种内置曲线槽的圆柱凸轮加工方法 (Method for machining cylindrical cam with built-in curve groove ) 是由 王少华 张求红 张振华 王胜峰 于 2020-12-03 设计创作，主要内容包括：本发明涉及一种内置曲线槽的圆柱凸轮加工方法,属于圆柱凸轮制备技术领域。本发明将圆柱凸轮设计成内套筒和外套筒两部分,通过分体加工外套筒和内套筒,保证了内套筒上曲线槽的加工精度,而且能够方便且准确检测曲线槽的精度,然后再将加工好的外套筒和内套筒组合在一起,这种分解加工再组合的加工方法,使加工质量达到曲线槽尺寸精度和表面粗糙度要求,解决了圆柱凸轮内置曲线槽槽型加工成型问题。(The invention relates to a method for processing a cylindrical cam with a built-in curve groove, and belongs to the technical field of cylindrical cam preparation. According to the processing method, the cylindrical cam is designed into the inner sleeve and the outer sleeve, the outer sleeve and the inner sleeve are processed separately, the processing precision of the curve groove on the inner sleeve is guaranteed, the precision of the curve groove can be conveniently and accurately detected, then the processed outer sleeve and the processed inner sleeve are combined together, the processing quality meets the requirements of the size precision and the surface roughness of the curve groove, and the problem of processing and forming of the groove type of the curve groove in the cylindrical cam is solved.)

1. A method for processing a cylindrical cam with a built-in curve groove is characterized by comprising the following steps: the cylindrical cam comprises an outer sleeve, an inner sleeve and a pin, the auxiliary tool related in the machining process comprises a base mandrel, an axial pressure ring, a nut and a positioning sample rod, the base mandrel is a stepped mandrel consisting of three cylinders with different diameters, and a screw thread is machined on the cylinder with the smallest diameter;

the processing method comprises the following steps:

(1) processing of inner sleeve and outer sleeve

Processing a positioning hole on the outer sleeve corresponding to the 0-degree position of the curved groove on the inner sleeve; more than four pin holes are processed at the upper side and the lower side of the corresponding positions of the curved grooves on the outer sleeve and the inner sleeve;

the inner sleeve is sleeved on the base mandrel, one end of the inner sleeve is positioned on the cylindrical end face with the largest diameter on the base mandrel, the axial pressure ring is sleeved on the cylinder with the smallest diameter on the base mandrel and positioned at the other end of the inner sleeve, and the inner sleeve is tightly pressed through the threaded connection of the nut and the cylinder with the smallest diameter on the base mandrel; cutting by using an end mill to process a curve groove on the inner sleeve, and detecting the accuracy of the curve groove of the inner sleeve by using an optical measuring instrument after the processing is finished so as to enable the accuracy to reach the design requirement of a drawing;

(2) assembly of inner and outer sleeves

The inner sleeve is in threaded adjustment connection with the outer sleeve, so that the positioning hole of the outer sleeve is overlapped with the 0-degree position of the curve groove of the inner sleeve, the positioning sample rod is inserted for positioning, the outer sleeve and the inner sleeve are fixedly connected through a pin, and then the positioning sample rod is removed to finish the processing of the cylindrical cam with the built-in curve groove.

2. The method for processing the cylindrical cam with the built-in curved groove as claimed in claim 1, wherein: the normal rake angle of the end mill used for processing the inner sleeve is 12-15 degrees.

3. The method for processing the cylindrical cam with the built-in curved groove as claimed in claim 1, wherein: the auxiliary tool further comprises a torque wrench, when the machining allowance of the width of the curve groove on the inner sleeve is not larger than 0.3mm, the nut is unscrewed, and the torque wrench is used to control the clamping force.

4. The method for processing the cylindrical cam with the built-in curved groove as claimed in claim 1, wherein: the wall thickness of the inner sleeve is not less than 2.0 mm.

5. The method for machining the cylindrical cam with the built-in curved groove as claimed in claim 3, wherein the method comprises the following steps: when the wall thickness of the inner sleeve is 2.0 mm-3.5 mm, the clamping force applied by the torque wrench is 4N-7N.

6. The method for processing the cylindrical cam with the built-in curved groove as claimed in claim 1, wherein: when the wall thickness of the inner sleeve is 2.0 mm-3.5 mm, the thread pitch of the threaded connection between the inner sleeve and the outer sleeve is 0.5 mm.

Technical Field

The invention relates to a method for processing a cylindrical cam with a built-in curve groove, and belongs to the technical field of cylindrical cam preparation.

Background

The cylindrical cam is a key part in a certain weapon guide system and is a critical part in a quality management system. The structural design precision and the processing precision of the variable-magnification part and the compensation part are high in requirement, and the moving amount of the variable-magnification group and the compensation group is controlled by two nonlinear cam curve grooves. Due to machining errors and deformation of the cam curve groove, backlash and the like generated by a fit clearance of the curve groove and the guide pin, the moving amount of the zooming group and the compensating group is inconsistent with a theoretical value, so that the axial displacement of an image surface is caused, and the loss of a tracking target of the guide system tracker is caused. Therefore, the precision of the two curve grooves of the cam plays a very critical role in the accuracy of the target captured by the missile.

The curved slot of the previous cylindrical cam is exposed as shown in fig. 1. The cam curved groove transmission structure is changed due to design, the purposes of shortening the guide transmission distance and effectively reducing the volume of the guide system control structure are achieved, and the curved groove of the cylindrical cam is changed from being exposed to being built-in. However, due to the limitation of part structures and the limitation of conventional machining methods, the conventional machining mode cannot meet the machining requirement of the built-in curve groove of the cylindrical cam.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a method for processing a cylindrical cam with a built-in curve groove.

The purpose of the invention is realized by the following technical scheme.

A method for processing a cylindrical cam with a built-in curved groove comprises an outer sleeve, an inner sleeve and a pin, wherein an auxiliary tool involved in a processing process comprises a base mandrel, an axial pressure ring, a nut and a positioning sample rod, the base mandrel is a stepped mandrel consisting of three cylinders with different diameters, and a cylinder with the smallest diameter is processed with a thread;

the processing method comprises the following steps:

(1) processing of inner sleeve and outer sleeve

Processing a positioning hole on the outer sleeve corresponding to the 0-degree position of the curved groove on the inner sleeve; more than four pin holes are processed at the upper side and the lower side of the corresponding positions of the curved grooves on the outer sleeve and the inner sleeve, so that the pin holes are distributed at the upper side and the lower side of the curved grooves on the inner sleeve;

the inner sleeve is sleeved on the base mandrel, one end of the inner sleeve is positioned on the cylindrical end face with the largest diameter on the base mandrel, the axial pressure ring is sleeved on the cylinder with the smallest diameter on the base mandrel and positioned at the other end of the inner sleeve, and the inner sleeve is tightly pressed through the threaded connection of the nut and the cylinder with the smallest diameter on the base mandrel; cutting by using an end mill to process a curve groove on the inner sleeve, and detecting the accuracy of the curve groove of the inner sleeve by using an optical measuring instrument after the processing is finished so as to enable the accuracy to reach the design requirement of a drawing;

furthermore, multiple experiments show that the increase of the normal front angle of the end mill lowers the cutting force, which is beneficial to controlling the machining precision; the normal rake angle of the end mill is reduced, the service life of the cutter is prolonged, but the cutting force is increased, the machining precision is unfavorable, and the potential deformation hidden danger is increased by the generated internal stress. The normal rake angle of the end mill is preferably 12 to 15 in consideration of comprehensive factors.

Further, auxiliary fixtures still includes the torque wrench, and when the machining allowance of curve groove width was not more than 0.3mm on the inner skleeve, the nut was unscrewed, changed into the size of torque wrench control clamp force.

Further, the wall thickness of the inner sleeve is not less than 2.0 mm.

Further, when the wall thickness of the inner sleeve is 2.0 mm-3.5 mm, the clamping force applied by the torque wrench is preferably in the range of 4N-7N.

(2) Assembly of inner and outer sleeves

The inner sleeve is in threaded adjustment connection with the outer sleeve, so that the positioning hole of the outer sleeve is overlapped with the 0-degree position of the curve groove of the inner sleeve, the positioning sample rod is inserted for positioning, the outer sleeve and the inner sleeve are fixedly connected through a pin, and then the positioning sample rod is removed to finish the processing of the cylindrical cam with the built-in curve groove.

Further, when the wall thickness of the inner sleeve is 2.0mm to 3.5mm, the thread pitch of the threaded connection between the inner sleeve and the outer sleeve is preferably 0.5 mm.

Has the advantages that:

(1) the processing method of the invention is that the inner sleeve and the outer sleeve are decomposed, processed and recombined, so that the processing quality meets the requirements of the dimensional accuracy and the surface roughness of the curved groove, and the problem of processing and forming of the groove type with the built-in curved groove is solved.

(2) Because the inner sleeve is a thin-walled part and the curved slot is open, it will deform to different degrees. The common part clamping method is that the outer wall of an outer jacket sleeve of a three-jaw chuck or the inner wall of an outer bearing part of an inner jaw, but the roundness of the part is out of tolerance due to uneven stress and scrapped due to the characteristic of a clamping structure. According to the invention, the clamping method is changed, the clamping stress direction of the part is changed, the end face of the cylindrical cam is used for clamping, the part is not stressed in the radial direction, and the part clamping deformation and the stress deformation in the machining process are effectively reduced, so that the problem of precision control of the groove shape of the built-in curve groove is solved.

(3) According to the invention, through the split machining method of the inner sleeve and the outer sleeve, whether the groove-shaped precision of the curve reaches the standard can be detected by using the optical measuring instrument, and the problem of the groove-shaped precision detection of the built-in curve groove is solved.

Drawings

Fig. 1 is a schematic three-dimensional structure diagram of a cylindrical cam with an exposed curved groove in the prior art.

Fig. 2 is a schematic three-dimensional structure diagram of the cylindrical cam with the built-in curved groove in the embodiment.

Fig. 3 is a cross-sectional view of a cylindrical cam with a built-in curved groove according to an embodiment.

FIG. 4 is a schematic view of the inner sleeve being clamped during machining.

The device comprises a base, a bolt, a base mandrel, a bolt, a base mandrel, an axial pressure ring, a nut, a machining center, a fourth shaft and a pull rod, wherein the bolt comprises 1-an outer sleeve, 2-an inner sleeve, 3-a pin, 4-the base mandrel, 5-the axial pressure ring, 6-the nut, 7-the machining center, and.

Detailed Description

The present invention is further illustrated by the following detailed description, wherein the processes are conventional unless otherwise specified, and the starting materials are commercially available from a public perspective unless otherwise specified.

Example 1

The cylindrical cam with the built-in curve groove comprises an outer sleeve 1, an inner sleeve 2 and a pin 3, wherein the outer sleeve 1 and the inner sleeve 2 are both made of materialsDuralumin alloys (e.g. LY)₁₂) And the thickness is 2.5mm, the pin 3 is made of stainless steel, as shown in fig. 2 and 3; the auxiliary tool involved in the processing process of the cylindrical cam comprises a base mandrel 4, an axial pressure ring 5, a nut 6, a torque wrench and a positioning sample rod, wherein the base mandrel 4 is a stepped mandrel consisting of three cylinders with different diameters, and a cylinder with the smallest diameter is provided with a thread, as shown in figure 4;

the processing steps of the cylindrical cam are as follows:

(1) machining of inner sleeve 2 and outer sleeve 1

Processing a positioning hole on the outer sleeve 1 corresponding to the 0-degree position of the curved groove on the inner sleeve 2; four pin holes are processed at the upper side and the lower side of the corresponding positions of the curved grooves on the outer sleeve 1 and the inner sleeve 2, so that the four pin holes are distributed at the upper side and the lower side of the two curved grooves on the inner sleeve 2, as shown in fig. 2 and 3;

the base mandrel 4 is installed on the processing equipment through a fourth shaft 7 of a processing center on the processing equipment and a pull rod 8, an inner sleeve 2 is sleeved on the base mandrel 4, one end of the inner sleeve 2 is positioned on the cylindrical end surface with the largest diameter on the base mandrel 4, an axial pressure ring 5 is sleeved on the cylinder with the smallest diameter on the base mandrel 4 and positioned at the other end of the inner sleeve 2, and the inner sleeve 2 is tightly pressed through threaded connection of a nut 6 and the cylinder with the smallest diameter on the base mandrel 4, as shown in fig. 4; selecting an end mill with a normal front angle of 12-15 degrees for cutting, slightly loosening the nut 6 when the width allowance of two curve grooves machined on the inner sleeve 2 is 0.2mm (namely the single-side width allowance of the curve grooves is 0.1mm), controlling a clamping force by using a torque wrench, wherein the clamping force applied by the torque wrench is 5N, and detecting the precision of the curve grooves of the inner sleeve 2 by using an optical measuring instrument after machining so as to enable the precision to reach the design requirement of a drawing;

(2) assembly of inner sleeve 2 and outer sleeve 1

The inner sleeve 2 is connected with the outer sleeve 1 in an adjusting mode through fine threads (the thread pitch is 0.5mm), so that the positioning hole of the outer sleeve 1 is overlapped with the 0-degree position of the curve groove of the inner sleeve 2 and is inserted into a positioning sample rod for positioning, the outer sleeve 1 and the inner sleeve 2 are fixedly connected through a dowel 3, then the positioning sample rod is detached, the combination assembly of the cylindrical cam with the built-in curve groove is completed, and the processing of the cylindrical cam with the built-in curve groove is completed.

In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.