CN110014273A - A kind of processing method and assembly method of pairs of involute planet gear - Google Patents

Abstract

The invention discloses a processing method and an assembling method for a pair of involute planetary gears. The processing method includes the following steps: Step S1: selecting a metal circular blank, and performing rough turning; Step S2: performing fine turning and turning chamfering, Obtaining a planetary gear blank; Step S3: grinding the planetary gear blank; Step S4: performing spline processing on the planetary gear blank obtained in Step S3 using the end face as a positioning reference to obtain an internal spline; Step S5: Step S4 Step S6: Carburizing heat treatment; Step S7: Grinding the end face; Step S8: The planetary gear obtained in Step S7 Grinding the outer tooth profile of the gear workpiece with the end face as the positioning reference to obtain the outer teeth; step S9: performing abrasive polishing treatment; step S10: cutting the planetary gear workpiece obtained in step S9 to form two involutes assembled in pairs Planetary gear.

Description

Processing method and assembling method of paired involute planetary gear

technical field

The invention relates to the technical field of gear processing, in particular to a processing method and an assembling method of a paired involute planetary gear.

Background technique

In recent years, with the rapid development of industrial robots, the demand for high-precision RV reducers for industrial robots has increased significantly, and almost all joints of heavy-duty robots need to use RV reducers. As the joint reducer of industrial robots, RV reducer has a significant impact on the transmission accuracy, bearing capacity and manufacturing cost of industrial robots. The RV reducer has much higher fatigue strength, stiffness and life than the harmonic drive commonly used in robots, and the hysteresis accuracy is stable, while the harmonic reducer, the motion accuracy will be significantly reduced with the increase of use time. Therefore, on average, each robot uses an average of 3-5 RV reducers. In 2013, the world's robot sales were 158,000 units, and about 900,000 reducers were required.

The assembly of the RV reducer has a huge impact on its performance. Before discussing the assembly process of the RV reducer in detail, it is necessary to fully understand and pay attention to the tooth parts in the RV reducer. The RV reducer is composed of two-stage reduction. The core components are ordinary involute cylindrical gears, double camshafts, flanges, cycloidal gears and pin gear housings. There are three parts that have strict requirements on teeth, namely: Involute planetary gears, double camshafts and cycloidal gears. In the traditional sense, the tooth base of a certain external tooth of an ordinary involute gear and the tooth base of the spline must be guaranteed to be on the same diameter, that is, the internal and external teeth of this part have clear positioning requirements for the teeth. The strict tooth alignment requirements of the involute planetary gears require that the hobbing and grinding of the splines must have accurate tooth alignment benchmarks, which not only requires the accuracy of the equipment to be improved, but also the spline and external teeth Before the forming process, how to ensure the accuracy of the teeth through the tooling is the key to the yield of the parts.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art, and to provide a processing method for paired involute planetary gears. The metal circular blank is first integrally processed, and finally divided to form pairs of involute planetary gears, and the production process is simple. ,low cost.

Another object of the present invention is to provide a method for assembling a pair of involute planetary gears.

The technical scheme of the present invention is: a processing method for paired involute planetary gears, comprising the following steps:

Step S1: Selecting a metal round blank, rough turning the outer circular surface and end face of the metal round blank, leaving a margin on one side;

Step S2: Finish turning and chamfering the outer circular surface and end face of the metal round blank obtained in step S1, leaving a margin on one side to obtain a planetary gear blank;

Step S3: grinding the end face of the planetary gear blank obtained in step S2;

Step S4: performing spline processing on the planetary gear blank obtained in step S3 with the end face as the positioning reference to obtain internal splines;

Step S5: The internal splines of the planetary gear blank obtained in step S4 are positioned by the spline mandrel, and the internal splines of the planetary gear blank are used as the positioning reference to perform gear hobbing processing to form a planetary gear workpiece with an external tooth profile;

Step S6: carrying out carburizing heat treatment on the planetary gear workpiece obtained in step S5;

Step S7: grinding the end face of the planetary gear workpiece obtained in step S6;

Step S8: grinding the outer tooth profile of the planetary gear workpiece obtained in step S7 with the end face as the positioning reference to obtain the outer teeth;

Step S9: perform abrasive polishing on the planetary gear workpiece obtained in step S8;

Step S10: The planetary gear workpiece obtained in step S9 is cut by wire-cutting wire to form two involute planetary gears assembled in pairs. The paired involute planetary gears obtained by this processing method do not need to be assembled strictly according to the requirements of the teeth, and the assembly efficiency is high, and the paired involute planetary gears and the camshaft do not generate eccentric force during the movement.

Further, in the step S1, a margin of 1.0-1.5 mm is left on one side.

Further, in the step S2, a margin of 0.3-0.5 mm is left on one side.

Further, in the step S3, the end face of the planetary gear blank is subjected to end face grinding, so that the flatness of the end face of the planetary gear blank is within 0.02 mm.

Further, in the step S6, the planetary gear workpiece is carburized until the carburized layer is 0.5-0.7 mm, quenched until the hardness is HRC58-63, and the core hardness is HRC30-40. The improved carburizing heat treatment is adopted to improve hardness and wear resistance, and prolong the working life of involute planetary gears.

Further, in the step S7, the end face of the planetary gear workpiece is subjected to end face grinding, so that the flatness of the end face of the planetary gear workpiece is within 0.005mm.

Further, in the step S9, the planetary gear workpiece is polished in the abrasive flow processing device, and the polishing time is 10-30 seconds.

Further, the metal round blank is made of 20CrMo alloy structural steel, and the 20CrMo alloy structural steel has the advantages of good toughness, high strength and wear resistance.

The invention also provides a method for assembling a pair of involute planetary gears, comprising a pair of involute planetary gears, a camshaft and an input shaft, wherein the involute planetary gear and the camshaft are respectively provided with radially opposite teeth Mark, keep the 90° between the involute planetary gear's radially opposite tooth mark and the camshaft's radially opposite tooth mark, translate and assemble the pair of involute planetary gears to the end of the camshaft, the involute planetary gear The internal splines of the involute gear mesh with the camshaft, and the external teeth of the involute planetary gear mesh with the input shaft. The internal splines and external teeth of the involute planetary gear of this assembly method do not need to comply with strict requirements on tooth alignment, which improves the assembly efficiency.

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

The method for processing the paired involute planetary gears of the present invention processes the metal circular blank as a whole, and finally divides it to form the paired involute planetary gears, thereby improving the processing efficiency, simple production process and low cost.

According to the assembling method of the paired involute planetary gears of the present invention, the inner splines and the outer teeth of the involute planetary gears of the assembling method do not need to comply with strict requirements for tooth alignment, which improves the assembly efficiency of the RV reducer and eliminates the need for gradual The eccentric force generated during the movement of the open-wire planetary gear and the camshaft.

Description of drawings

FIG. 1 is a flow chart of the processing method of the paired involute planetary gear of the present invention.

FIG. 2 is a flow chart of the carburizing heat treatment process of the present invention.

3 is a schematic diagram of the assembly of the pair of involute planetary gears and the camshaft of the present invention.

Involute planetary gear 1, internal spline 11, external teeth 12, input shaft 2, camshaft 3, radial tooth mark 4.

Detailed ways

The present invention will be further described in detail below with reference to the examples, but the embodiments of the present invention are not limited thereto.

Example

As shown in FIG. 1 , a method for processing a paired involute planetary gear in the present embodiment includes the following steps:

Step S1: select a metal round billet made of 20CrMo alloy structural steel, and roughen the outer circular surface and the end face of the metal round billet, leaving a margin of 1.5mm on one side;

Step S2: Finish turning and chamfering the outer circular surface and end face of the metal round blank obtained in step S1, leaving a margin of 0.30 mm on one side to obtain a planetary gear blank;

Step S3: grinding the end face of the planetary gear blank obtained in step S2, so that the flatness of the end face of the planetary gear blank is within 0.02mm;

Step S4: performing spline processing on the planetary gear blank obtained in step S3 with the end face as the positioning reference to obtain internal splines;

Step S5: The internal splines of the planetary gear blank obtained in step S4 are positioned by the spline mandrel, and the internal splines of the planetary gear blank are used as the positioning reference to perform gear hobbing processing to form a planetary gear workpiece with an external tooth profile;

Step S6: As shown in Figure 2, the planetary gear workpiece obtained in step S5 is subjected to carburizing heat treatment, the planetary gear workpiece is carburized to a carburized layer of 0.5 mm, quenched to a hardness of HRC58, and a core hardness of HRC35;

Step S7: grinding the end face of the planetary gear workpiece obtained in step S6, so that the flatness of the end face of the planetary gear workpiece is within 0.005mm;

Step S8: grinding the outer tooth profile of the planetary gear workpiece obtained in step S7 with the end face as the positioning reference to obtain the outer teeth;

Step S9: perform abrasive polishing on the planetary gear workpiece obtained in step S8, and the polishing time is 25 seconds;

Step S10: The planetary gear workpiece obtained in the step S9 is cut by a slow-moving wire to form two involute planetary gears assembled in pairs.

Example 2

As shown in FIG. 3 , this embodiment provides a method for assembling a pair of involute planetary gears, including a pair of involute planetary gears 1 , a camshaft 3 and an input shaft 2 , the involute planetary gears 1 and The camshafts 3 are respectively provided with radially aligned tooth marks 4 to keep the radial alignment of the involute planetary gear and the radial alignment of the camshaft at 90°, and translate the paired involute planetary gears. And assembled to the end of the camshaft, the inner spline of the involute planetary gear meshes with the camshaft, and the outer teeth of the involute planetary gear meshes with the input shaft. The internal splines and external teeth of the involute planetary gear of this assembly method do not need to comply with strict requirements on tooth alignment, which improves the assembly efficiency.

As described above, the present invention can be well realized, and the above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of implementation of the present invention; It is covered by the scope of protection of the claims of the present invention.

Claims (9)

1. a kind of processing method of pairs of involute planet gear, which comprises the following steps:

Step S1: choosing round metal blank, and the periphery and end face progress to round metal blank are rough turn, and unilateral there are surpluses；

Step S2: the periphery of the obtained round metal blank of step S1 and end face are subjected to smart car and vehicle chamfering, unilateral there are remaining Amount obtains planetary gear blank；

Step S3: the end face of the obtained planetary gear blank of step S2 is subjected to face grinding processing；

Step S4: the planetary gear blank that step S3 is obtained carries out the processing of garland key by positioning datum of end face, obtains interior flower Key；

Step S5: the internal spline for the planetary gear blank that step S4 is obtained is positioned by splined mandrel, planetary gear hair Base carries out gear hobbing process by positioning datum of internal spline, forms the planetary gear workpiece with outer teeth profile；

Step S6: the planetary gear workpiece that step S5 is obtained carries out carburizing heat treatment；

Step S7: the end face of the obtained planetary gear workpiece of step S6 is subjected to face grinding processing；

Step S8: the planetary gear workpiece that step S7 is obtained carries out roll flute processing to outer teeth profile using end face as positioning datum, obtains To external tooth；

Step S9: the planetary gear workpiece that step S8 is obtained carries out abrasive polishing processing；

Step S10: the planetary gear workpiece that step S9 is obtained carries out low-speed WEDM, forms two assembled in pairs and gradually opens Line planetary gear.

2. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that in the step S1 It is unilateral that there are 1.0-1.5mm surpluses.

3. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that in the step S2 It is unilateral that there are 0.3-0.5mm surpluses.

4. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that the step S3 In, the end face of planetary gear blank carries out face grinding processing, makes the flatness of the end face of planetary gear blank in 0.02mm.

5. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that in the step S6 Planetary gear workpiece carbonization to carburized layer is 0.5-0.7mm, and being quenched to hardness is HRC58-63, core hardness HRC30-40.

6. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that the step S7 In, the end face of planetary gear workpiece carries out face grinding processing, makes the flatness of the end face of planetary gear workpiece in 0.005mm.

7. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that the step S9 In, planetary gear workpiece is processed by shot blasting in abrasive flow machining device, and the time of polishing treatment is 10-30 seconds.

8. the processing method of pairs of involute planet gear according to claim 1, which is characterized in that the metal round billet Material is made of 20CrMo structural alloy steel.

9. a kind of assembly method of pairs of involute planet gear, which is characterized in that including pairs of involute planet gear, convex It is respectively equipped on wheel shaft and input shaft, involute planet gear and camshaft radial to tooth label, holding involute planet gear It is radial to the radial to being in 90 ° between tooth label of tooth label and camshaft, pairs of involute planet gear is translated and is filled It is assigned to tail end of camshaft, the internal spline of involute planet gear is engaged with camshaft, the external tooth of involute planet gear and input Axis engagement.