阅读说明：本技术 一种平衡轴齿轮、制作方法和具有该齿轮的齿轮副 (Balance shaft gear, manufacturing method and gear pair with same ) 是由 程党明 刘勇 郑跃伟 范艺翀 叶权源 黄小芳 程瑶 侯晓江 于 2021-07-13 设计创作，主要内容包括：本发明涉及一种平衡轴齿轮、制作方法和具有该齿轮的齿轮副,该平衡轴齿轮包括齿轮主体和齿轮固定机构,所述齿轮主体由多块钢齿轮和树脂齿轮相间排列而成,齿轮主体两侧端面均为钢齿轮,相邻两块钢齿轮之间设置有一块树脂齿轮,所述钢齿轮与树脂齿轮的形状、尺寸相同；所述齿轮固定机构包括固定钢片和铆钉,所述齿轮主体一侧设置有固定钢片,固定钢片、钢齿轮和树脂齿轮上对应位置设有多个定位孔,所述铆钉穿过定位孔将固定钢片、钢齿轮和树脂齿轮夹紧固定后构成所述平衡轴齿轮。本发明通过对钢齿轮和树脂齿轮进行组合,所得齿轮无需很高的加工精度要求即能保证良好的NVH效果,解决了纯树脂齿轮强度不足、剪式齿轮啮合噪音及加工精度要求高的问题。(The invention relates to a balance shaft gear, a manufacturing method and a gear pair with the gear, wherein the balance shaft gear comprises a gear main body and a gear fixing mechanism, the gear main body is formed by arranging a plurality of steel gears and resin gears at intervals, the end surfaces of two sides of the gear main body are both the steel gears, a resin gear is arranged between two adjacent steel gears, and the steel gears and the resin gears have the same shape and size; the gear fixing mechanism comprises a fixing steel sheet and a rivet, wherein the fixing steel sheet is arranged on one side of the gear main body, a plurality of positioning holes are formed in corresponding positions of the fixing steel sheet, the steel gear and the resin gear, and the rivet penetrates through the positioning holes to clamp and fix the fixing steel sheet, the steel gear and the resin gear to form the balance shaft gear. According to the invention, the steel gear and the resin gear are combined, so that the obtained gear can ensure a good NVH (noise, vibration and harshness) effect without high machining precision requirement, and the problems of insufficient strength of a pure resin gear, high meshing noise of a shear type gear and high machining precision requirement are solved.)

1. The utility model provides a balance shaft gear, includes gear main part (1) and gear fixing mechanism, its characterized in that:

the gear body (1) is formed by arranging a plurality of steel gears (2) and a plurality of resin gears (3) at intervals, the end faces of two sides of the gear body (1) are the steel gears (2), one resin gear (3) is arranged between every two adjacent steel gears (2), and the steel gears (2) and the resin gears (3) are identical in shape and size;

the gear fixing mechanism comprises a fixing steel sheet (4) and rivets (5), one side end face of the gear body (1) is provided with the fixing steel sheet (4), the fixing steel sheet (4) abuts against the end face of the steel gear (2) on one side of the gear body (1), a plurality of positioning holes (6) are formed in the corresponding positions of the fixing steel sheet (4), the steel gear (2) and the resin gear (3), and the rivets (5) penetrate through the positioning holes (6) to clamp and fix the fixing steel sheet (4), the steel gear (2) and the resin gear (3) to form the balance shaft gear.

2. A balance shaft gear according to claim 1, wherein said steel gear (2) is made of a gear steel having a yield strength of 550MPa or more, said resin gear (3) is made of a high-strength, high-heat-resistant polyamide resin, said resin gear (3) has a yield strength of 240MPa or more and a water absorption of 0.25% or less.

3. A balance shaft gear according to claim 1, wherein the gear body (1) is of one-piece construction.

4. A manufacturing method of a balance shaft gear is characterized by comprising the following steps:

s1, firstly, selecting a die, a fixed steel sheet (4) and a rivet (5) with matched sizes and specifications, and fixing a plurality of steel gear blanks in the die;

s2, adjusting the width of the gap between the steel gear blanks in a die to be equal to the thickness of the steel gear blanks according to the measured thickness of the steel gear blanks;

s3, preparing a resin gear blank by using polyamide resin as a raw material between the steel gear blanks in a vulcanization mode, so that the steel gear blank and the resin gear blank are integrated;

and S4, finally, taking out the gear in the die, grinding to obtain a gear main body (1), flatly attaching the fixed steel sheet (4) to one side of the gear main body (1), and fixing by using a rivet (5) to complete the manufacturing of the balance shaft gear.

5. The method as claimed in claim 4, wherein the step S1 comprises fixing a plurality of steel gear blanks in the mold, wherein the steel gear blanks have a side surface roughness of Ra0.25-0.8.

6. The method as claimed in claim 4, wherein in step S3, the resin gear blank is prepared by vulcanizing polyamide resin between the steel gear blanks, and the mold cavity temperature is controlled at 240 ℃ and the resin solution temperature is controlled at 360 ℃ and the resin injection pressure is 5.5-7.0MPa and the injection speed is controlled at 8-12m/S during the vulcanization process.

7. A gear pair, characterized by comprising two balance shaft gears according to any one of claims 1 to 3, respectively designated as a first balance shaft gear (7) and a second balance shaft gear (8), the steel gear (2) and the resin gear (3) of the first balance shaft gear (7) and the second balance shaft gear) being in staggered mesh with each other: the steel gear (2) on the first balance shaft gear (7) is meshed with the resin gear (3) on the second balance shaft gear (8), and the resin gear (3) on the first balance shaft gear (7) is meshed with the steel gear (2) on the second balance shaft gear (8).

8. A gear pair according to claim 6, characterized in that the fixed steel sheet (4) on one side of the first balance shaft gear (7) corresponds to the steel gear (2) on one side of the second balance shaft gear (8), the steel gear (2) on the other side of the first balance shaft gear (7) corresponds to the fixed steel sheet (4) on the other side of the second balance shaft gear (8), and the fixed steel sheets (4) on the first balance shaft gear (7) and the second balance shaft gear (8) are respectively positioned on two sides of the gear pair.

9. A gear pair according to claim 6, characterised in that the steel gear (2) and the resin gear (3) of the first balance shaft gear (7) and the second balance shaft gear (8) are of equal thickness.

Technical Field

The invention relates to the technical field of design of balance shaft gears and gear pairs, in particular to a balance shaft gear, a manufacturing method and a gear pair with the gear.

Background

The function of balanced axle is balanced engine second order reciprocating inertia, improves engine NVH, but balanced axle module generally adopts gear drive, and current balanced axle gear product has following defect:

the balance shaft gear scheme, namely the shear type gear, is noise-reduced, the requirement on the precision of shear teeth is high, the processing cost is high, the gear center distance is controlled, the requirement on the tolerance precision of engine associated parts is high, the NVH has the problem of large consistency, and the friction power loss is large.

The balance shaft gear scheme II is that a steel gear is meshed with a resin gear, the NVH effect is good, but the strength of a pure resin gear is low, the requirement of a high-power and high-torque engine cannot be met, and the resin material technology is mastered in few foreign suppliers and is subject to foreign patents.

The invention designs a brand new balance shaft gear scheme, solves the problem that pure resin gears are insufficient in strength and cannot meet the requirements of high-power and high-torque engines, and also solves the problems of high requirements on meshing noise and machining precision of shear type gears.

Disclosure of Invention

The present invention is directed to solving at least one of the above problems.

A first object of the present invention is to provide a balance shaft gear.

The second purpose of the invention is to provide a manufacturing method of the balance shaft gear.

A third object of the present invention is to provide a gear pair for an engine balance shaft.

In order to realize the first purpose of the invention, the invention provides a balance shaft gear which is composed of n steel gears and (n-1) resin gears which are arranged alternately, and the n steel gears and the (n-1) resin gears are fixed by rivets, so that the problem that the strength of a pure resin gear is insufficient and the requirement of a high-power and high-torque engine cannot be met is solved, and the specific structure of the balance shaft gear comprises a gear main body and a gear fixing mechanism;

the gear body is formed by arranging a plurality of steel gears and a plurality of resin gears at intervals, the end faces of two sides of the gear body are both steel gears, a resin gear is arranged between every two adjacent steel gears, and the steel gears and the resin gears are the same in shape and size;

the gear fixing mechanism comprises a fixing steel sheet and a rivet, wherein the fixing steel sheet is arranged on the end face of one side of the gear main body, the fixing steel sheet is abutted against the end face of the steel gear on one side of the gear main body, a plurality of positioning holes are formed in corresponding positions of the fixing steel sheet, the steel gear and the resin gear, and the rivet penetrates through the positioning holes to clamp and fix the fixing steel sheet, the steel gear and the resin gear to form the balance shaft gear.

The steel gear is made of gear steel with yield strength more than or equal to 550MPa, the resin gear is made of high-strength and high-heat-resistance polyamide resin, the yield strength of the resin gear is more than or equal to 240MPa, and the water absorption rate is less than or equal to 0.25%; the gear main body is of an integrated structure.

In the technical scheme, the balance shaft gear is formed by arranging n steel gears and (n-1) resin gears at intervals, in order to ensure the gear precision, the thickness of the steel gear = the thickness of the resin gear = the thickness of the fixed steel sheet, and the steel gear is matched with the resin gear, so that the gear can ensure a good NVH effect without high machining precision requirement, and the cost is reduced by about 20% compared with the machining (needing to finish the gear) of a pure steel gear; in order to ensure the strength of the steel gear and the resin gear, n steel gears and (n-1) resin gears are fixed by using m rivets so as to ensure the strength of the steel gears and the resin gears.

In the technical scheme, preferably, 1 fixed steel sheet is additionally arranged on the end face of the steel gear, and the fixed steel sheets are abutted against the steel gear on the end face of the gear, so that the steel gear can be effectively ensured to be well meshed with the resin gear, and the gear is assisted to be axially positioned; preferably, the yield strength of the gear steel selected by the steel gear is more than or equal to 550MPa, so that the meshing teeth of the steel gear do not need to be subjected to heat treatment, the strength of the gear can be ensured, and the cost is further reduced; preferably, the resin gear material adopts the Aramidde reinforced fiber as a base material, and the high-strength and high-heat-resistance polyamide resin is injected into the base material, so that the yield strength of the resin gear material is more than or equal to 240MPa, the gear material has good engine oil resistance while the strength of the gear is ensured, the water absorption rate is less than or equal to 0.25%, the storage environment of 3 months can be met, and squeaking noise cannot be generated in the subsequent use process due to excessive water absorption in the storage process.

To achieve the second object of the present invention, an embodiment of the present invention provides a method for manufacturing a balance shaft gear, including the steps of:

s1, firstly, selecting a die, a fixed steel sheet and a rivet with matched sizes and specifications, and fixing a plurality of steel gear blanks in the die;

s2, adjusting the width of the gap between the steel gear blanks in a die to be equal to the thickness of the steel gear blanks according to the measured thickness of the steel gear blanks;

s3, preparing a resin gear blank by using polyamide resin as a raw material between the steel gear blanks through a vulcanization process, so that the steel gear blank and the resin gear blank are integrated;

and S4, finally, taking out the gear in the die, grinding to obtain a gear main body, flatly attaching the fixed steel sheet to one side of the gear main body, and fixing by using a rivet to finish the manufacturing of the balance shaft gear.

In order to avoid the difficulty of adhering resin due to the smoothness of the side surface of the steel gear, a plurality of steel gear blanks are fixed in the mold in step S1, and the side surface roughness of the steel gear blanks is Ra0.25-0.8.

Preferably, in order to achieve better vulcanization effect, in step S3, the resin gear blank is prepared by using polyamide resin as a raw material between the steel gear blanks through vulcanization, wherein during vulcanization, the mold cavity temperature is controlled to be 200-.

According to the technical scheme, the steel gear blank is fixed in a die, the thickness of the steel gear blank is set to be H, the interval width between the steel gear blanks is also set to be H, then the resin gear blanks are vulcanized between the steel gear blanks to be integrated, and after grinding treatment, the obtained balance shaft gear can meet the strength requirement of the gear due to the integrated gear structure while the gear precision is guaranteed.

To achieve the third object of the present invention, an embodiment of the present invention provides a gear pair, including two balance shaft gears as described in the above embodiments, respectively denoted as a first balance shaft gear and a second balance shaft gear, where the steel gear and the resin gear of the first balance shaft gear and the second balance shaft gear are staggered and meshed with each other: the steel gear on the first balance shaft gear is meshed with the resin gear on the second balance shaft gear, and the resin gear on the first balance shaft gear is meshed with the steel gear on the second balance shaft gear.

The fixed steel sheet on one side of the first balance shaft gear corresponds to the steel gear on one side of the second balance shaft gear, the steel gear on the other side of the first balance shaft gear corresponds to the fixed steel sheet on the other side of the second balance shaft gear, and the fixed steel sheets on the first balance shaft gear and the second balance shaft gear are respectively positioned on two sides of the gear pair; and the thicknesses of the steel gear and the resin gear in the first balance shaft gear and the second balance shaft gear are equal.

In the technical scheme, the gear pair is meshed with the resin gear in a staggered mode respectively through the steel gear, certain damping is achieved due to the resin gear, the energy of gear meshing can be well absorbed, the gear pair is insensitive to gaps, the precision requirement is low (only 8-level precision), and the gear meshing noise is avoided while the gear pair processing cost is reduced.

The gear pair in the technical scheme has all the advantages in the embodiment because the balance shaft gear in the embodiment is adopted.

Additional aspects and advantages of the invention 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 invention.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural view of a balance shaft gear of the present invention;

FIG. 2 is a left side view of the balance shaft gear of the present invention;

FIG. 3 is an exploded view of the balance shaft gear of the present invention;

FIG. 4 is a flow chart of a method of making a balance shaft gear of the present invention;

FIG. 5 is an assembled schematic view of the gear pair of the present invention;

FIG. 6 is a front view of the gear pair of the present invention.

The reference numerals in the figures illustrate: 1. a gear body; 2. a steel gear; 3. a resin gear; 4. fixing the steel sheet; 5. riveting; 6. positioning holes; 7. a first balance shaft gear; 8. a second balance shaft gear.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without any inventive step, are within the scope of the present invention.

Example 1:

as shown in fig. 1 to 3, a balance shaft gear of the present invention includes a gear body 1 and a gear fixing mechanism;

the gear body 1 is formed by arranging a plurality of steel gears 2 and a plurality of resin gears 3 at intervals, the end faces of two sides of the gear body 1 are the steel gears 2, one resin gear 3 is arranged between two adjacent steel gears 2, and the steel gears 2 and the resin gears 3 are the same in shape and size;

the gear fixing mechanism comprises a fixing steel sheet 4 and a rivet 5, wherein the fixing steel sheet 4 is arranged on the end face of one side of the gear body 1, the fixing steel sheet 4 is abutted against the end face of the steel gear 2 on one side of the gear body 1, a plurality of positioning holes 6 are formed in corresponding positions of the fixing steel sheet 4, the steel gear 2 and the resin gear 3, and the rivet 5 penetrates through the positioning holes 6 to clamp and fix the fixing steel sheet 4, the steel gear 2 and the resin gear 3 to form the balance shaft gear.

The steel gear 2 is made of gear steel with yield strength more than or equal to 550MPa, the resin gear 3 is made of high-strength and high-heat-resistance polyamide resin, the yield strength of the resin gear 3 is more than or equal to 240MPa, and the water absorption rate is less than or equal to 0.25%; the gear body 1 is of an integrated structure.

Specifically, the balance shaft gear is formed by n steel gears 2 and n-1 resin gears 3 which are arranged at intervals, in order to ensure the gear precision, the thickness of the steel gear 2 = the thickness of the resin gear 3 = the thickness of the fixed steel sheet 4, and the steel gear 2 is matched with the resin gear 3, so that the gear can ensure a good NVH effect without high machining precision requirement, and the cost of the gear is reduced by about 20% compared with the gear needing fine grinding in the machining of a pure steel gear; in order to ensure the strength of the steel gear 2 and the resin gear 3, a plurality of rivets 5 are adopted to fix the n steel gears 2 and the n-1 resin gears 3 so as to ensure the strength.

Furthermore, in the embodiment of the invention, the fixed steel sheet 4 is additionally arranged on the end face of the steel gear 2, and the fixed steel sheet 4 is abutted against the steel gear 2 on the end face of the gear, so that the steel gear 2 can be effectively ensured to be well meshed with the resin gear 3, and the gear can be axially positioned; the yield strength of the gear steel selected for the steel gear 2 is more than or equal to 550MPa, so that the meshing teeth of the steel gear 2 do not need to be subjected to heat treatment, the gear strength can be ensured, and the cost is further reduced; the resin gear 3 is made of an Aramidde reinforced fiber as a base material, and high-strength and high-heat-resistance polyamide resin is injected into the base material, so that the yield strength of the resin gear is more than or equal to 240MPa, the gear has good engine oil resistance while the strength of the gear is ensured, the water absorption rate is less than or equal to 0.25%, the storage environment of 3 months can be met, and squeal noise generated in the subsequent use process due to excessive water absorption in the storage process can be avoided.

Example 2

As shown in fig. 4, a method for manufacturing a balance shaft gear includes the following steps:

s1, firstly, selecting a die, a fixed steel sheet 4 and a rivet 5 which are matched in size and specification, and fixing a plurality of steel gear blanks in the die;

s2, adjusting the width of the gap between the steel gear blanks in a die to be equal to the thickness of the steel gear blanks according to the measured thickness of the steel gear blanks;

s3, preparing a resin gear blank by using polyamide resin as a raw material between the steel gear blanks through a vulcanization process, so that the steel gear blank and the resin gear blank are integrated;

and S4, finally, taking out the gear in the die, grinding to obtain a gear main body 1, flatly attaching a fixed steel sheet 4 to one side of the gear main body 1, and fixing by using a rivet 5 to finish the manufacturing of the balance shaft gear.

In this embodiment, in order to avoid the difficulty in adhering resin due to the smoothness of the side surface of the steel gear, the roughness of the side surface of the steel gear blank used in step S1 is ra0.25-0.8.

In order to achieve better vulcanization effect, in the vulcanization process in step S3, the mold cavity temperature is controlled at 240 ℃ in 200-.

Specifically, in this embodiment, the steel gear blank is fixed in the mold, the thickness of the steel gear blank is set to be H, the interval width between the steel gear blanks is also H, then the resin gear blank is vulcanized between the steel gear blanks to form an integral body, and after grinding, the obtained balance shaft gear can meet the strength requirement of the gear due to the integral gear structure while ensuring the gear precision.

Example 3

As shown in fig. 5 to 6, a gear pair includes two balance shaft gears as described in embodiment 1, which are respectively identified as a first balance shaft gear 7 and a second balance shaft gear 8, and the first balance shaft gear 7 and the steel gear 2 and the resin gear 3 of the second balance shaft gear are in staggered engagement with each other: the steel gear 2 on the first balance shaft gear 7 is meshed with the resin gear 3 on the second balance shaft gear 8, and the resin gear 3 on the first balance shaft gear 7 is meshed with the steel gear 2 on the second balance shaft gear 8.

The fixed steel sheet 4 on one side of the first balance shaft gear 7 corresponds to the steel gear 2 on one side of the second balance shaft gear 8, the steel gear 2 on the other side of the first balance shaft gear 7 corresponds to the fixed steel sheet 4 on the other side of the second balance shaft gear 8, and the fixed steel sheets 4 on the first balance shaft gear 7 and the second balance shaft gear 8 are respectively positioned on two sides of the gear pair.

The thicknesses of the steel gear 2 and the resin gear 3 in the first balance shaft gear 7 and the second balance shaft gear 8 are equal.

The gear pair in this embodiment through stagger the meshing respectively with steel gear and resin gear, because of the resin gear has certain damping, the energy of absorption gear engagement that can be fine to it is insensitive to the clearance of gear pair, the required precision low 8 grades of precision can, avoided the meshing noise of gear when reducing the gear pair processing degree of difficulty and cost.

In conclusion, when the gear and the gear pair thereof in the embodiment of the invention are used on the balance shaft of the engine, the problem that the pure resin gear is insufficient in strength and cannot meet the requirement of a high-power and high-torque engine can be effectively solved, and the problems of high requirements on meshing noise and machining precision of the shear gear are solved.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.