Tool for stabilizing quenching deformation of internal gear

Abstract

A tool for stabilizing quenching deformation of an internal gear comprises a protective sleeve, the protective sleeve is of a cylindrical structure, a vertically-through stepped hole is formed in the center of the protective sleeve, the stepped hole comprises an upper circular groove and a lower through hole, and the circular groove and the through hole are vertically through; the inner diameter of the circular groove is larger than that of the through hole; the inner wall of the circular groove is in clearance fit with the outer circumference of the thin wall corresponding to the inner gear, and the height of the circular groove is larger than the tooth width of the inner gear. And the aperture of the through hole is consistent with the addendum circle of the internal gear. The circular groove is installed on the outer circumference of a thin wall corresponding to an inner gear of a part in a sliding fit mode. And then quenching treatment is carried out on the part. Due to the fact that the outer circumference of the thin wall corresponding to the internal gear is consistently protected by the circular groove, the deformation amount of the internal gear after quenching is stable and consistent, and then the carburized layer and the hardness of the internal gear after mechanical grinding meet the requirements.

Description

Technical Field

[0001] The utility model belongs to a production tool, in particular to a tool for stabilizing the quenching deformation of an internal gear. Background Art

[0002] In parts with gears, the surface of the gears will be required to be carburized and quenched. Slow cooling is used during carburization, and rapid cooling is used during quenching. For thin-walled parts with internal gears, such as Figure 1 As shown in the figure, due to the thin thickness of the internal gear, it is easy to deform after carburizing and quenching, and the deformation is irregular. In order to meet the accuracy of the internal gear, further grinding will be performed. However, due to the irregular deformation, the carburized layer and hardness of some internal gear surfaces after mechanical grinding cannot meet the requirements of the design drawings, and ultimately the parts cannot be repaired and are scrapped, causing a lot of economic losses.

[0003] If improvements are made to the quenching process, such as cooling speed, protective coating or quenching medium, it will have a certain effect on controlling deformation, but the investment is large and the work is cumbersome. Summary of the invention

[0004] In view of this, the utility model provides a tooling for stabilizing the quenching deformation of an internal gear, which can directly protect the thin-walled internal gear so that its deformation after quenching is stable and consistent, meeting subsequent processing needs.

[0005] The technical solution adopted by the utility model is: a tooling for stabilizing the quenching deformation of an internal gear, comprising a protective sleeve, the protective sleeve is a cylindrical structure, a stepped hole penetrating up and down is arranged at the center of the protective sleeve, the stepped hole comprises a circular groove at the top and a through hole at the bottom, the circular groove and the through hole penetrating up and down; the inner diameter of the circular groove is larger than the inner diameter of the through hole; the inner wall of the circular groove forms a clearance fit with the thin-walled outer circumference corresponding to the internal gear, and the height of the circular groove is larger than the tooth width of the internal gear; the aperture of the through hole is consistent with the tooth top circle of the internal gear.

[0006] Furthermore, the protective cover is made of medium carbon structural steel.

[0007] Furthermore, the inner diameter of the circular groove is 0.05-0.1 mm larger than the corresponding outer diameter of the thin wall of the internal gear.

[0008] Furthermore, the height of the circular groove accounts for 2 / 3 of the height of the outer circumference of the thin wall of the part.

[0009] Furthermore, the height of the through hole is consistent with the tooth width of the internal gear.

[0010] The beneficial effect of the utility model is that the circular groove of the tool is slidably mounted on the thin-walled outer circumference corresponding to the internal gear of the part. Then the part is quenched. Since the circular groove provides consistent protection for the thin-walled outer circumference corresponding to the internal gear, the deformation of the internal gear after quenching can be stable and consistent, and the carburized layer and hardness of the internal gear after mechanical grinding meet the requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the structure of the parts to be protected by the utility model;

[0012] Figure 2 It is a structural schematic diagram of the utility model;

[0013] Figure 3 yes Figure 2 A top view of

[0014] Figure 4 It is an assembly diagram of the utility model and parts.

[0015] In the figure: 1. part, 2. internal gear, 3. thin-walled outer circumference, 4. protective cover, 5. circular groove, 6. through hole. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0017] like Figure 2 , Figure 3 and Figure 4 As shown, a tool for stabilizing the quenching deformation of an internal gear includes a protective sleeve 4, which is a cylindrical structure. The protective sleeve 4 is made of medium carbon structural steel. A stepped hole is provided in the center of the protective sleeve 4, which passes through from top to bottom. The stepped hole includes a circular groove 5 at the top and a through hole 6 at the bottom. The circular groove 5 and the through hole 6 pass through from top to bottom. The inner diameter of the circular groove 5 is larger than the inner diameter of the through hole 6. The inner wall of the circular groove 5 forms a clearance fit with the thin-walled outer circumference 3 corresponding to the internal gear 2. The inner diameter of the circular groove 5 is 0.05-0.1 mm larger than the diameter of the thin-walled outer circumference 3 corresponding to the internal gear 2. The height of the circular groove 5 is greater than the tooth width of the internal gear 2. The height of the circular groove 5 accounts for 2 / 3 of the height of the thin-walled outer circumference 3 of the part 1, so as to avoid the thin-walled outer circumference of the part 1 from forming an inverted cone. The aperture of the through hole 6 is substantially consistent with the tooth top circle of the internal gear 2, and the height of the through hole 6 is consistent with the tooth width of the internal gear 2. This is to facilitate the circulation of liquid during rapid quenching, so that the part 1 can be cooled sufficiently, and to avoid the small diameter of the through hole 6 causing poor liquid circulation, affecting the cooling rate, and reducing the quenching quality of the part 1.

[0018] During quenching, the circular groove 5 of the tool is slidably mounted on the thin-walled outer circumference 3 corresponding to the internal gear 2 of the part 1, the end of the internal gear 2 abuts against the bottom of the circular groove 5, and the shaft hole of the part 1 is connected with the stepped hole. Then the part 1 is quenched. Since the circular groove 5 provides consistent protection for the thin-walled outer circumference 3 corresponding to the internal gear 2, the deformation of the internal gear 2 after quenching can be stable and consistent, and the carburized layer and hardness of the internal gear 2 after mechanical grinding meet the requirements.

Claims

1. A tool for stabilizing the quenching deformation of an internal gear, characterized in that: It includes a protective cover, which is a cylindrical structure. A stepped hole is provided in the center of the protective cover, which passes through from top to bottom. The stepped hole includes a circular groove at the top and a through hole at the bottom. The circular groove and the through hole pass through from top to bottom. The inner diameter of the circular groove is larger than the inner diameter of the through hole. The inner wall of the circular groove forms a clearance fit with the thin-walled outer circumference corresponding to the internal gear, and the height of the circular groove is larger than the tooth width of the internal gear. The aperture of the through hole is consistent with the tooth top circle of the internal gear.

2. A tool for stabilizing the quenching deformation of an internal gear as claimed in claim 1, characterized in that: The protective cover is made of medium carbon structural steel.

3. A tool for stabilizing the quenching deformation of an internal gear as claimed in claim 1, characterized in that: The inner diameter of the circular groove is 0.05-0.1 mm larger than the outer circumference diameter of the thin wall corresponding to the internal gear.

4. A tool for stabilizing the quenching deformation of an internal gear as claimed in claim 1, characterized in that: The height of the circular groove accounts for 2 / 3 of the height of the outer circumference of the thin wall of the part.

5. A tool for stabilizing the quenching deformation of an internal gear as claimed in claim 1, characterized in that: The height of the through hole is consistent with the tooth width of the internal gear.

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