CN219755259U - Flexspline and harmonic reducer - Google Patents

Abstract

The utility model discloses a flexible gear and a harmonic reducer, and relates to the technical field of harmonic reducers, wherein the flexible gear comprises a cylinder part, a partition part and a mounting part, and the cylinder part and the partition part need to be elastically deformed in the running process of the flexible gear. The nitriding layers are formed on the surfaces of the first wall and the second wall of the barrel part, so that the surfaces of the first wall and the second wall have higher hardness, and the wear resistance of the barrel part and the partition part is improved; the thickness of nitriding layer of the inner side or the outer side of the first wall of the cylinder part and the second wall of the partition part accounts for 5% to 30% of the wall thickness, and the proportion of the flexible gear base material and the nitriding layer is designed in a reasonable range, so that the surface of the flexible gear has enough hardness, and meanwhile, the flexible gear is higher in structural strength and better in overall toughness, and the requirement of elastic deformation in the operation process is met.

Description

Flexspline and harmonic reducer

Technical Field

The utility model relates to the technical field of harmonic reducers, in particular to a flexible gear and a harmonic reducer.

Background

The harmonic reducer has the advantages of compact structure, small volume, light weight, large transmission ratio and bearing capacity, high transmission precision and the like, so that the harmonic reducer is widely applied to the industries of robots, automation and the like. The harmonic speed reducer comprises three basic components of a wave generator, a flexible gear and a rigid gear. In the working engineering of the harmonic speed reducer, the tooth part of the flexible gear is meshed with the tooth part of the rigid gear, and the inner hole of the flexible gear is matched with the outer ring of the flexible bearing. The inner hole of the flexible gear and the outer ring of the flexible bearing have relative axial and circumferential movements, so the hardness requirement of the inner hole of the flexible gear is higher. However, in the working process of the harmonic reducer, the flexible gear needs to be repeatedly elastically deformed, so that the hardness of the flexible gear cannot be too high.

Disclosure of Invention

The present utility model aims to solve at least one of the technical problems existing in the prior art. Therefore, the utility model provides the flexible gear, which has good surface abrasion resistance and can meet the requirement of elastic deformation of the flexible gear in the running process.

The utility model further provides a harmonic reducer with the flexible gear.

According to an embodiment of the first aspect of the present utility model, a flexspline includes: a cylinder part, one end of which is provided with a tooth part; a partition portion connected to one end of the cylindrical portion away from the tooth portion, the partition portion being disposed around a circumferential direction of the cylindrical portion; the mounting part is connected with the partition part and used for mounting the flexible gear; wherein the surfaces of the first wall of the cylinder portion and the second wall of the partition portion form a nitriding layer, the thickness of the nitriding layer on the inner side or the outer side of the first wall is 5% to 30% of the wall thickness of the first wall, and the thickness of the nitriding layer on the inner side or the outer side of the second wall is 5% to 30% of the wall thickness of the second wall.

The flexible gear provided by the embodiment of the utility model has at least the following beneficial effects:

the nitriding layers are formed on the surfaces of the first wall and the second wall of the barrel part, so that the surfaces of the first wall and the second wall have higher hardness, and the wear resistance of the barrel part and the partition part is improved; the thickness of nitriding layer of the inner side or the outer side of the first wall of the cylinder part and the second wall of the partition part accounts for 5% to 30% of the wall thickness, and the proportion of the flexible gear base material and the nitriding layer is designed in a reasonable range, so that the surface of the flexible gear has enough hardness, and meanwhile, the cylinder part and the partition part which are elastically deformed in the running process of the flexible gear have higher structural strength and better overall toughness.

According to some embodiments of the utility model, the nitrided layer is formed on both the inner and outer surfaces of the first wall and the nitrided layer is formed on both the inner and outer surfaces of the second wall.

According to some embodiments of the utility model, the thickness of the nitrided layer inside or outside the thinnest portion of the partition is 10% to 20% of the wall thickness of the second wall.

According to some embodiments of the utility model, the nitrided layer has a thickness of less than or equal to 0.05mm.

According to some embodiments of the utility model, the nitrided layer includes a white bright layer on a side of the nitrided layer remote from the flex substrate.

According to some embodiments of the utility model, the thickness of the white light layer is less than or equal to 10 μm.

According to some embodiments of the utility model, the thickness of the white bright layer is greater than 0% and less than or equal to 20% of the thickness of the nitrided layer.

According to some embodiments of the utility model, the surface hardness of the flexspline is 400HV to 700HV.

According to some embodiments of the utility model, the surface residual stress of the flexspline is a compressive stress, and an absolute value of the compressive stress is greater than or equal to 400MPa.

According to a second aspect of the utility model, a harmonic reducer comprises the flexspline described in the above embodiment.

The harmonic reducer provided by the embodiment of the utility model has at least the following beneficial effects:

by adopting the flexible gear of the embodiment of the first aspect, the nitriding layers are formed on the surfaces of the first wall of the cylinder part and the second wall of the partition part, so that the surfaces of the first wall and the second wall have higher hardness, and the wear resistance of the cylinder part and the partition part is improved; the thickness of the nitriding layer on the inner side or the outer side of the first wall of the cylinder part and the second wall of the partition part accounts for 5-30% of the wall thickness, and the proportion of the flexible gear base material and the nitriding layer is designed in a reasonable range, so that the surface of the flexible gear has enough hardness, and the cylinder part and the partition part which are elastically deformed in the running process of the flexible gear have higher structural strength and better overall toughness; thereby prolonging the service life of the harmonic speed reducer.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.

Drawings

The utility model is further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a schematic diagram of a harmonic reducer according to an embodiment of the present utility model;

FIG. 2 is a schematic structural view of the flexspline of FIG. 1;

FIG. 3 is an enlarged schematic view of the flexspline of FIG. 2 at barrel A;

fig. 4 is an enlarged schematic view of the flexspline shown in fig. 2 at the spacer B.

Reference numerals:

a harmonic speed reducer 1000;

a flexspline 100; a first tooth 110; an inner bore 120; a flex base 130; a nitriding layer 140; a white bright layer 141; a hardness gradient layer 142; a cylindrical portion 150; a first wall 151; a partition 160; a second wall 161; a mounting portion 170;

rigid wheel 200; a second tooth portion 210;

a wave generator 300; a flexible bearing 310; cam 320.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.

In the description of the present utility model, it should be understood that the direction or positional relationship indicated with respect to the description of the orientation, such as up, down, etc., is based on the direction or positional relationship shown in the drawings, is merely for convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the apparatus or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

In the description of the present utility model, plural means two or more. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present utility model, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present utility model can be reasonably determined by a person skilled in the art in combination with the specific contents of the technical scheme.

The harmonic speed reducer 1000 is used as one of precise speed reducers, has the advantages of compact structure, small volume, light weight, large transmission ratio and bearing capacity, high transmission precision and the like, and is widely applied to industries such as electronics, aerospace, robots, automation and the like.

Referring to fig. 1, the harmonic reducer 1000 includes three basic components of a flexspline 100, a rigid spline 200, and a wave generator 300, wherein the flexspline 100 is a flexible external gear, the rigid spline 200 is a rigid ring gear, and the wave generator 300 is composed of a flexible bearing 310 and a cam 320.

During operation of the harmonic reducer 1000, the first tooth portion 110 of the flexspline 100 meshes with the second tooth portion 210 of the rigid gear 200, and the inner bore 120 of the flexspline 100 mates with the outer race of the flexible bearing 310. The abrasion loss between the outer ring of the flexible bearing 310 and the inner hole 120 of the flexible gear 100 is large, so that the hardness requirement of the inner hole 120 of the flexible gear 100 is high, and good abrasion resistance is obtained.

When the wave generator 300 is installed into the inner hole 120 of the flexspline 100, the flexspline 100 is forced to elastically deform to form an ellipse, the flexspline 100 needs to be repeatedly deformed during the operation of the harmonic speed reducer 1000, and there is relative movement between the inner hole 120 of the flexspline 100 and the outer ring of the flexspline bearing 310 in the axial direction and the circumferential direction. Therefore, the hardness of the flexspline 100 cannot be too high, so that the overall brittleness of the flexspline 100 is prevented from being excessively high.

Therefore, in order to solve the above-mentioned problems, the surface of the flexspline 100 according to the embodiment of the present utility model has sufficient hardness, and the flexspline 100 has higher structural strength and better overall toughness, and meets the requirement of elastic deformation during the operation of the harmonic reducer 1000.

Referring to fig. 1 and 2, a flexspline 100 according to an embodiment of the present utility model includes a cylindrical portion 150, a spacer 160, and a mounting portion 170. The first tooth 110 is provided on the outer side wall of one end of the tube 150, and the other end of the tube 150 is connected to the partition 160. The inner side wall of the tube 150 surrounds the inner bore 120, and the wave generator 300 is mounted to the inner side wall of the tube 150. The partition 160 is provided around the circumferential direction of the tube 150, for example, the partition 160 extends outward of the tube 150 or inward of the tube 150. The mounting portion 170 is connected to an end of the partition 160 remote from the cylinder portion 150, and the mounting portion 170 is used for mounting the flexspline 100, for example, in a flange structure or the like. The spacer 160 and the tube 150 are typically integrally formed because they need to be elastically deformed during operation of the flexspline 100. The spacer 160 and the tube 150 are thin-walled members, one end of each thin-walled member is engaged with the rigid wheel, and the other end of each thin-walled member is provided with torque output by the mounting portion 170. The connection between the mounting portion 170 and the partition 160 may be integrally formed, or may be welded, and is not particularly limited herein.

Referring to fig. 2, 3 and 4, the surface of the first wall 151 of the cylinder 150 and the second wall 161 of the spacer 160 forms the nitrided layer 140. The nitriding layer 140 may be formed inside the first wall 151 or outside the first wall 151; when the nitrided layer 140 is formed on the inner side of the first wall 151, the thickness of the nitrided layer 140 is 5% to 30% of the wall thickness of the first wall 151; when the nitrided layer 140 is formed on the outer side of the first wall 151, the nitrided layer 140 has a thickness of 5% to 30% of the wall thickness of the first wall 151. Providing the nitriding layer 140 on the surface of the first wall 151 is advantageous in improving the surface hardness of the barrel portion 150 and improving the wear resistance of the barrel portion 150.

The nitrided layer 140 may also be formed on the inside of the second wall 161 or the outside of the second wall 161. When the nitrided layer 140 is formed on the inner side of the second wall 161, the thickness of the nitrided layer 140 is 5% to 30% of the wall thickness of the second wall 161; when the nitrided layer 140 is formed on the outer side of the second wall 161, the thickness of the nitrided layer 140 is 5% to 30% of the wall thickness of the second wall 161. Providing the nitrided layer 140 on the surface of the second wall 161 is advantageous in improving the surface hardness of the partition 160 and the wear resistance of the partition 160.

According to the embodiment of the utility model, the thickness of the nitriding layer 140 on the inner side or the outer side of the first wall 151 of the cylinder part 150 and the second wall 161 of the partition part 160 accounts for 5-30% of the wall thickness, and the thickness ratio of the flexible gear base material 130 to the nitriding layer 140 is designed in a reasonable range, so that the thickness of the nitriding layer 140 is not too small to influence the surface wear resistance of the flexible gear 100, and is not too large to influence the structural strength and the overall toughness of the flexible gear 100. Therefore, while the surface of the flexspline 100 has sufficient hardness, the cylindrical portion 150 and the spacer 160, which elastically deform during operation of the flexspline 100, have higher structural strength and better overall toughness, thereby improving the service life of the harmonic reducer 1000.

Fig. 3 shows a layered structure of the first wall 151 of the barrel 150 of the flexspline 100. It is understood that the surface of the flexspline 100 is formed with a nitrided layer 140, and the outer surface of the nitrided layer 140 is a white bright layer 141. The first wall 151 includes the flex base 130 and the nitrided layer 140 on the surface of the flex base 130. It is understood that nitrided layer 140 includes a white bright layer 141 and a graded hardness layer 142. The white and bright layer refers to a compound layer composed of a zeta phase, an epsilon phase and a gamma/phase or one or two phases of the zeta phase, the epsilon phase and the gamma/phase on the surface layer of the nitriding workpiece, and is also called a compound layer or a compound layer. The hardness gradient layer 142 is a partial structure of the nitriding layer 140 from which the white bright layer 141 is removed, and the hardness gradient layer 142 is located between the white bright layer 141 and the flexspline base 130. The white bright layer 141 has a higher hardness and a higher brittleness than the hardness gradient layer 142. The white bright layer 141 is arranged on the outer surface of the nitriding layer 140, so that the wear resistance of the nitriding layer 140 can be effectively improved, the surface of the flexible gear 100 has higher hardness, and the wear resistance of the tooth surface of the first tooth part 110 of the flexible gear 100 and the inner hole 120 of the flexible gear 100 is improved.

Fig. 4 shows a layered structure of the second wall 161 of the partition 160 of the flexspline 100. It is to be understood that the outer surface of the nitriding layer 140 of the flex gear 100 according to another embodiment of the present utility model may not be formed with the white bright layer 141. Because the brittleness of the white bright layer 141 is relatively large, the absence of the white bright layer 141 is advantageous in improving the overall toughness of the flexspline 100.

Referring to fig. 3, the nitrided layer 140 is formed on both the inner and outer surfaces of the first wall 151, and the sum of the thicknesses of the nitrided layer 140 on the inner and outer sides of the first wall 151 is 10% to 60% of the wall thickness of the first wall 151, so that the thickness ratio of the flexspline base 130 and the nitrided layer 140 is in a reasonable range, so that the structural strength of the cylindrical portion 150 is higher and the overall toughness is better while the surface of the cylindrical portion 150 has sufficient hardness.

Referring to fig. 4, the nitrided layer 140 is formed on both the inner and outer surfaces of the second wall 161, and the sum of the thicknesses of the nitrided layer 140 on the inner and outer sides of the second wall 161 is 10% to 60% of the wall thickness of the second wall 161, so that the thickness ratio of the flexspline base 130 and the nitrided layer 140 is in a reasonable range, so that the surface of the partition 160 has sufficient hardness, and at the same time, the structural strength of the partition 160 is higher and the overall toughness is better.

In the design of the flexspline 100 of the harmonic reducer 1000, the spacer 160 has the thinnest portion, which is a partial area where the distance between the inner curve and the outer curve of the spacer 160 is the smallest. Referring to fig. 4, the thickness of the nitrided layer 140 on the inner or outer side of this partial area is 10% to 20% of the wall thickness of the second wall 161. It can be appreciated that the thinnest point of the spacer 160 is located approximately in the middle of the spacer 160, and the thinnest point of the spacer 160 is the weak point of the flexspline 100. In the manufacturing of the flexspline 100, according to the actual product, the nitrided layer 140 may be formed on the inner side of the thinnest portion of the spacer 160, or the nitrided layer 140 may be formed on the outer side of the thinnest portion of the spacer 160, or the nitrided layer 140 may be formed on both the inner side and the outer side. The thickness of the unilateral nitriding layer 140 accounts for 10% to 20% of the wall thickness of the second wall 161, so that the thickness ratio of the thinnest part of the spacer 160 to the flexible gear base 130 and the nitriding layer 140 is in a better range, the thinnest part of the spacer 160 has enough hardness, and meanwhile, the thinnest part of the spacer 160 has higher structural strength and better toughness, and the overall performance of the flexible gear 100 is further improved.

Referring to fig. 3, it can be understood that the thickness of nitrided layer 140 is less than or equal to 0.05mm. For example, the thickness of nitrided layer 140 may be 0.01mm, 0.03mm, 0.05mm, and the like. The thickness of the nitriding layer 140 satisfies the above range, so that the surface of the flexspline 100 has enough hardness, and meanwhile, the flexspline 100 has higher structural strength and better overall toughness, and meets the requirement of elastic deformation of the flexspline 100 in the operation process of the harmonic reducer 1000.

Referring to fig. 3, it can be understood that the thickness of the white bright layer 141 is less than or equal to 10 μm. For example 1 μm, 5 μm, 10 μm, etc. The white bright layer 141 is harder and more brittle. Therefore, when the above parameter range is satisfied, compared with the thickness of the nitriding layer 140, the bright white layer 141 is only provided with a thinner layer on the outer surface of the nitriding layer 140, so that the wear resistance of the flexspline 100 can be effectively improved, and meanwhile, the overall toughness of the flexspline 100 is not affected, and the flexspline 100 is not adversely deformed elastically in the running process.

It is understood that, as another example, the thickness of the white bright layer 141 is greater than 0% and less than or equal to 20% of the thickness of the nitrided layer 140, thereby reducing the influence of the white bright layer 141 on the overall toughness of the flexspline 100.

Referring to fig. 3, it can be understood that the hardness of the hardness gradient layer 142 gradually decreases in the direction toward the flexspline substrate 130 until the hardness is the same as that of the flexspline substrate 130, so that the connection between the nitriding layer 140 and the flexspline substrate 130 is more stable, and the overall toughness of the flexspline 100 is also better.

Referring to fig. 2 and 3, it can be understood that the surface hardness of the flexspline 100 is 400HV to 700HV. For example, the surface hardness of the flexspline 100 may be 400HV, 500HV, 600HV, 700HV, and so on. When the above parameter range is satisfied, the wear resistance of the flexspline 100 is better, and the wear resistance of the first tooth 110 and the inner hole 120 of the flexspline 100 is better, so that the wear amount when the first tooth 110 of the flexspline 100 and the second tooth 210 of the rigid spline 200 are meshed can be reduced, the wear amount when the inner hole 120 of the flexspline 100 and the outer ring of the flexspline bearing 310 are matched can be reduced, and the service life of the flexspline 100 can be prolonged.

Referring to fig. 2 and 3, it can be understood that the surface residual stress of the flexspline 100 is compressive stress, and the absolute value of the compressive stress is 400Mpa or more. For example, the absolute value of the compressive stress may be 400MPa, 500MPa, 600MPa, etc. The residual stress is compressive stress, so that the microcrack expansion of the surface of the flexible gear 100 can be inhibited, and when the parameter range is met, the fatigue strength of the tooth root of the flexible gear 100 meets the requirement, and the flexible gear 100 is effectively prevented from breaking.

It is understood that the roundness of the inner bore 120 of the flexspline 100 is less than or equal to 0.05mm. For example, the roundness of the inner bore 120 of the flexspline 100 may be 0.01mm, 0.03mm, 0.05mm, etc. When the above parameter ranges are satisfied, the performance of the harmonic reducer 1000 can be effectively improved. When the roundness of the inner hole 120 of the flexspline 100 is greater than 0.05mm, the performance of the harmonic reducer 1000 is drastically reduced.

Referring to fig. 1, a harmonic reducer 1000 according to an embodiment of the present utility model includes a flexspline 100 according to the above embodiment. According to the harmonic reducer 1000 of the embodiment of the utility model, with the adoption of the flexspline 100 of the embodiment of the first aspect, the flexspline 100 forms the nitriding layer 140 on the surfaces of the first wall 151 of the cylinder 150 and the second wall 161 of the partition 160, so that the surfaces of the first wall 151 and the second wall 161 have higher hardness, and the wear resistance of the cylinder 150 and the partition 160 is improved; the thickness of the nitriding layer 140 on the inner side or the outer side of the first wall 151 of the cylinder part 150 and the second wall 161 of the partition 160 accounts for 5% to 30% of the wall thickness, and the proportion of the flexible gear base 130 and the nitriding layer 140 is designed in a reasonable range, so that the cylinder part 150 and the partition 160 which are elastically deformed in the running process of the flexible gear 100 have higher structural strength and better overall toughness while the surface of the flexible gear 100 has enough hardness; thereby improving the service life of the harmonic reducer 1000.

Since the harmonic reducer 1000 adopts all the technical solutions of the flexspline 100 in the above embodiments, at least all the beneficial effects brought by the technical solutions in the above embodiments are provided, and will not be described in detail herein.

In order to manufacture the flexspline of the above embodiment, a surface treatment process of the flexspline 100 is adopted, so that the deformation of the manufactured flexspline 100 is small, and meanwhile, the surface hardness of the flexspline 100 can be improved, and the fatigue strength of the tooth root of the flexspline 100 and the wear resistance of the surface of the flexspline 100 are enhanced.

The surface treatment process of the flexspline 100 of the present embodiment specifically includes the following steps:

s101: and processing the alloy structural steel base material to prepare a flexible gear semi-finished product. It is understood that the semi-finished flexspline is formed by blanking, forging, stamping, spinning, finish turning, hobbing and other processing steps of the alloy structural steel substrate.

S102: and (5) activating the semi-finished product of the flexible gear. It will be appreciated that the activation treatment acts to form fluoride on the surface of the flex semifinished product, for example on the surface of the first teeth 110 of the flex 100, and on the surfaces of the inner and outer sides of the side walls of the flex 100. For example, fluoride can be formed on the surface of the semi-finished product of the flexspline by introducing fluorine-containing gas into the semi-finished product of the flexspline, and the operation is simple and the control is convenient. Of course, fluoride can be formed on the surface of the flexspline semi-finished product in other ways.

S103: and carrying out low-temperature nitriding treatment on the flexible gear semi-finished product. It is understood that since the flexspline 100 is a thin-walled member, deformation is likely to occur. Whereas the nitriding temperature of the conventional nitriding treatment is higher than 500 c, the deformation amount of the flexspline 100 is large at this temperature. Therefore, the deformation of the flexible gear 100 can be effectively reduced by adopting low-temperature nitriding treatment, the installation precision of the flexible gear 100 is improved, and the precision of the harmonic reducer 1000 is further improved. Wherein the nitriding temperature of the low-temperature nitriding is controlled to be between 350 ℃ and 450 ℃, for example 350 ℃, 380 ℃, 400 ℃ and 450 ℃.

However, it is difficult for the flexspline 100 to form a stable nitrided layer 140 in a temperature range of low temperature nitriding of 350 ℃ to 450 ℃. Therefore, step S102 is added in the process of this embodiment, after the activation treatment is performed on the semi-finished product of the flexspline, the nitrided layer 140 can be formed in the temperature range of low-temperature nitriding, so that the surface hardness of the flexspline 100 is improved, and the wear resistance of the tooth surface and the inner hole 120 of the flexspline 100 is improved. For example, step S103 of the present embodiment may include: placing the cleaned flexible gear semi-finished product in a nitriding furnace, controlling the nitriding temperature to be 350-450 ℃, and introducing ammonia gas to keep the temperature for a certain period of time. It will be appreciated that the flow rate of the ammonia gas introduced and the duration of the heat preservation need to be adjusted according to the parameters of the nitriding layer 140, and are not particularly limited herein.

S104: and (5) shot blasting is carried out on the semi-finished product of the flexible gear. And (5) performing shot blasting treatment on the semi-finished flexible gear product to obtain a finished flexible gear product. The shot blasting can increase the surface residual stress of the flexible gear 100, improve the fatigue strength of the flexible gear 100, strengthen the fatigue strength of the tooth root and the side wall of the flexible gear 100, improve the running stability of the flexible gear 100, and further improve the running stability of the harmonic reducer 1000.

According to the surface treatment process of the flexspline 100, the above steps are adopted, so that the flexspline semi-finished product can be subjected to nitriding treatment at a low temperature of 350-450 ℃, and a nitriding layer 140 is formed on the surface of the flexspline 100, so that the surface hardness of the flexspline 100 is improved, and the wear resistance of the tooth surface of the first tooth part 110 of the flexspline 100 and the inner hole 120 of the flexspline 100 is improved; meanwhile, the deformation of the flexible gear 100 can be effectively reduced by adopting low-temperature nitriding treatment, and the installation accuracy of the flexible gear 100 is improved; the fatigue strength of the flexible gear 100 can be improved by adopting shot blasting, the fatigue strength of the tooth root and the side wall of the flexible gear 100 is enhanced, and the running stability of the flexible gear 100 is improved; thereby improving the service life of the harmonic reducer 1000.

The embodiments of the present utility model have been described in detail with reference to the accompanying drawings, but the present utility model is not limited to the above embodiments, and various changes can be made within the knowledge of one of ordinary skill in the art without departing from the spirit of the present utility model.

Claims (10)

1. The flexbile gear, its characterized in that includes:

a cylinder part, one end of which is provided with a tooth part;

a partition portion connected to one end of the cylindrical portion away from the tooth portion, the partition portion being disposed around a circumferential direction of the cylindrical portion;

the mounting part is connected with the partition part and used for mounting the flexible gear;

wherein the surfaces of the first wall of the cylinder portion and the second wall of the partition portion form a nitriding layer, the thickness of the nitriding layer on the inner side or the outer side of the first wall is 5% to 30% of the wall thickness of the first wall, and the thickness of the nitriding layer on the inner side or the outer side of the second wall is 5% to 30% of the wall thickness of the second wall.

2. The flexspline of claim 1 wherein: the nitriding layer is formed on the inner side and the outer side of the first wall, and the nitriding layer is formed on the inner side and the outer side of the second wall.

3. The flexspline of claim 1 wherein: the thickness of the nitrided layer on the inner side or the outer side of the thinnest part of the partition part accounts for 10 to 20% of the wall thickness of the second wall.

4. The flexspline of claim 1 wherein: the thickness of the nitriding layer is less than or equal to 0.05mm.

5. The flexspline according to any one of claims 1 to 4, wherein: the nitriding layer comprises a white bright layer, and the white bright layer is positioned on one side, far away from the flexible gear base material, of the nitriding layer.

6. The flexspline of claim 5 wherein: the thickness of the white bright layer is less than or equal to 10 mu m.

7. The flexspline of claim 5 wherein: the thickness of the white bright layer is more than 0% and less than or equal to 20% of the thickness of the nitriding layer.

8. The flexspline of claim 1 wherein: the surface hardness of the flexible gear is 400HV to 700HV.

9. The flexspline of claim 1 wherein: the surface residual stress of the flexible gear is compressive stress, and the absolute value of the compressive stress is more than or equal to 400MPa.

10. Harmonic speed reducer, its characterized in that: comprising a flexspline according to any one of claims 1 to 9.