CN219802073U

CN219802073U - Axle sleeve and belt pulley package assembly suitable for automobile alternating current generator

Info

Publication number: CN219802073U
Application number: CN202321110697.9U
Authority: CN
Inventors: 顾秋麟; 沈斌雄; 万海涛; 陆晓亮; 陈骏; 殳海琴
Original assignee: Zhejiang Dadongwu Auto Motor Co ltd
Current assignee: Zhejiang Dadongwu Auto Motor Co ltd
Priority date: 2023-05-10
Filing date: 2023-05-10
Publication date: 2023-10-03
Anticipated expiration: 2033-05-10

Abstract

The utility model relates to the technical field of automobile alternators, in particular to a shaft sleeve and belt pulley assembly structure suitable for an automobile alternator, which comprises an axial limiting sleeve part which is sleeved on a rotor shaft and limits a belt pulley in the axial direction, and an expanding connecting sleeve part which is fixedly connected with the right end of the axial limiting sleeve part in the axial direction and is used for being inserted and expanded with the belt pulley, wherein the assembling and disassembling are convenient, and the fastening effect is good.

Description

Axle sleeve and belt pulley package assembly suitable for automobile alternating current generator

Technical Field

The utility model relates to the technical field of automobile alternators, in particular to a shaft sleeve and belt pulley assembly structure suitable for an automobile alternator.

Background

The automobile alternating-current generator is used as a main power supply of an automobile, the working reliability and durability of the automobile alternating-current generator are required to be high, the driving environment of the automobile is complex relative to other mechanical equipment, the driving habit of a driver, road conditions, weather and the like can all cause certain influence on the loss of automobile parts in the running process of the automobile, in the common mechanical faults of the generator, the loosening of a belt pulley can lead to the working failure of the generator, the loosening of the belt pulley can damage a rotor shaft, if the belt pulley falls down, serious surrounding equipment can be damaged, the serious faults are caused, and aiming at the situation, the belt pulley of the automobile generator is generally provided with anti-loosening measures, and the existing measures have the following steps:

method 1: the half-round key is added, namely, the key connection is the most common mode for realizing the circumferential fixation between the shaft and the parts on the shaft so as to transmit the motion and the torque, and on the automobile alternating current generator, the half-round key is selected, is generally used for light load, is suitable for the circumferential fixation of the end part of the shaft, and is used for transmitting the torque by the side face, and can swing around the arc curvature center of the groove bottom in the key groove on the shaft, so that the assembly is convenient, but the key groove on the shaft is deeper in cutting, the weakening of the shaft is larger, and the proper size is selected by referring to the GB/T1099.1-2003 standard when in use. The semicircular key is used for fixing the shaft and the circumference of the belt pulley, so that corresponding fault risks exist, namely, a key groove on the shaft is deeper, the strength of the shaft is inevitably weakened, and the rotor shaft is at risk of breakage during high-load operation.

Method 2: the traditional taper sleeve belt pulley is used, namely, the taper sleeve belt pulley is a mechanical connection assembly of a taper sleeve embedded between the installation shaft and the belt pulley, the belt pulley and the taper sleeve are locked by mainly relying on an inner hexagonal screw, and then the installation shaft is tightly held by the expansion force of the taper sleeve to complete fastening.

The taper sleeve belt pulley is of a very mature design, and is implemented according to the standard of the expansion connection sleeve form and the basic size of JB/T7934-1999, the specification of the taper sleeve mainly comprises two types of TB taper sleeve and QD taper sleeve, the hole at the matching position of the taper sleeve and the belt pulley is half, three complete holes can be correspondingly formed by three light holes on the taper sleeve and three threaded holes on the belt pulley, and two complete holes are formed by two threaded holes on the taper sleeve and two light holes on the belt pulley. When the belt pulley is assembled, three inner hexagon screws are screwed into three threaded holes of the belt pulley, the screws are continuously screwed into the threaded holes of the belt pulley in sequence, the screws are pushed to the small ends of the taper holes of the belt pulley by the transmission action of the threads, the three taper holes on the taper sleeve are not completely machined, so that when the front ends of the screws prop against the bottom ends of the taper holes, the force is transmitted to the taper sleeve, the taper sleeve moves towards the small ends of the taper holes of the belt pulley relative to the belt pulley, and at the moment, the taper sleeve continuously holds the mounting shaft due to taper, and the pressure of the shaft is reacted with the taper sleeve and then is transmitted to the belt pulley. The belt pulley, the taper sleeve and the shaft are tightly connected together through the expansion force of the taper sleeve.

On the contrary, when dismantling the belt pulley, withdraw from the belt pulley screw hole with hexagon socket head cap screw, reuse two screws to spin in the screw hole of taper sleeve, both ends symmetry are screwed up with force, the screw advances towards the little end of belt pulley taper hole, when the screw front end reached the belt pulley bottom, on having transmitted the belt pulley with the power, at this moment between belt pulley and the taper sleeve, will break away from the taper of belt pulley with the taper sleeve through the ejecting of screw, and the belt pulley will lose the constraint of taper sleeve yet, can light dismantlement from the installation epaxial.

After the taper sleeve belt pulley is installed, an assembly body in interference fit is formed, positive pressure exists on the joint surface of the taper sleeve and the shaft, and the generated friction force can improve the torque and force transmitted by the belt pulley.

Compared with the conventional straight-hole belt pulley, the taper sleeve belt pulley has a plurality of advantages: the structure is reliable, the taper sleeve has the self-centering function, can transfer higher torque and force, and can prevent the belt pulley from loosening and the like. The advantages of the taper sleeve belt pulley are numerous, but the advantages are also that: compared with the conventional straight hole type belt pulley, the belt pulley has high cost, the complexity of installation and disassembly is higher than that of other conventional belt pulleys, the belt pulley size specification of the automobile generator is relatively smaller, and in consideration of the inner space of the belt pulley, some types are not suitable for installation of the taper sleeve. In addition, the taper sleeve and pulley start a plurality of small holes on the inner side, which has an influence on the strength of the structure, is easy to break and has serious faults.

Method 3: the simplified taper sleeve of the belt pulley has lower cost compared with the traditional taper sleeve belt pulley, is more suitable for small-sized power generation equipment such as an automobile generator, does not need to process a unthreaded hole and a threaded hole for fastening and disassembling in the taper sleeve and the belt pulley, and directly uses a fastening nut of the belt pulley as a pressure source to expand and fasten the taper sleeve.

The simplified taper sleeve has the following defects: for convenient dismantlement, the top design processing of taper sleeve has the recess, and this kind of design, though easy to assemble, it is convenient to have the taper sleeve of threaded hole far away when dismantling, need use specialized tool just can accomplish the dismantlement, and because the existence of recess, and the recess is in the position of tip, and self structural strength is weaker relatively, dismantles in this kind of recess position, causes the taper sleeve cracked easily and makes the dismantlement work increase the degree of difficulty, and this kind of instrument is used in the inboard region of belt pulley, damages the belt pulley easily.

The chinese patent of application number 201621408535.3 discloses a generator belt pulley locking structure, including pivot, belt pulley and be located the pivot tip is and right the lock nut that the belt pulley was fixed a position, its characterized in that: the belt pulley comprises a toothed groove, a first conical surface facing the lock nut and a side end surface of the belt pulley; the taper sleeve comprises a second taper surface, a limiting surface for limiting axial movement of the belt pulley and a buffer port for guiding deformation of the taper sleeve, wherein the second taper surface is in contact with the first taper surface, the limiting surface is opposite to the side end surface of the belt pulley, the structure is similar to the second improvement method, the annular structure of the limiting surface is similar to the structure of the simplified taper sleeve with the groove, the simplified taper sleeve with the groove is also of the annular limiting surface structure formed at the groove, the simplified taper sleeve with the groove is convenient for disassembly by special disassembly tools, the simplified taper sleeve is used in the belt pulley, the problems are easy to generate, the axial length of the limiting surface in the structure cannot be long, the installation of a locking nut is not influenced, the thin structural strength of the protrusion at the limiting surface is slightly low, and the effect of clasping a rotor shaft is general.

Disclosure of Invention

The utility model aims to provide a shaft sleeve and belt pulley assembly structure which is convenient to assemble and disassemble and good in fastening effect and is suitable for an automobile alternating current generator.

The above object of the present utility model is achieved by the following technical solutions: the shaft sleeve comprises an axial limiting sleeve part which is sleeved on a rotor shaft and is used for limiting a belt pulley in the axial direction, and an expansion connecting sleeve part which is fixedly connected with the right end of the axial limiting sleeve part in the axial direction and is used for being inserted and expanded with the belt pulley.

As the preferable mode of the utility model, the axial limiting sleeve part is a sleeve body which is C-shaped in section, can shrink in the radial direction and has cylindrical surfaces on the inner surface and the outer surface.

Preferably, the expansion connecting sleeve part is a sleeve body which is C-shaped in section and can be contracted in the radial direction, the inner surface is a cylindrical surface, the outer surface is a conical surface, and the outer surface of the expansion connecting sleeve part gradually reduces in radial size from left to right.

As the preferable mode of the utility model, the C-shaped opening position of the axial limiting sleeve part and the C-shaped opening position of the expansion connecting sleeve part are positioned at the same circumferential position and are communicated with each other to form a straight shape.

Preferably, the inner surface of the axial stop collar portion and the inner surface of the expansion connecting sleeve portion are concentric and have the same radial dimension.

Preferably, the radial dimension of the outer surface of the axial stop collar portion is smaller than or equal to the maximum radial dimension of the outer surface of the expansion connecting sleeve portion.

As the optimization of the utility model, the axial limiting sleeve part and the expansion connecting sleeve part are cast iron sleeve bodies or steel sleeve bodies or plastic sleeve bodies and are integrally connected and formed.

The utility model provides a belt pulley package assembly suitable for car alternator, includes belt pulley, rotor shaft, be equipped with left bearing and right bearing on the rotor shaft and assemble on the rotor shaft and be located the rotor between left bearing and the right bearing, the belt pulley is installed in the position department of the right-hand member portion of rotor shaft, still includes a kind of axle sleeve suitable for car alternator of aforesaid.

As the optimization of the utility model, a round table-shaped expansion hole for inserting and expanding the expansion connecting sleeve, a middle supporting hole sleeved on the rotor shaft and an operation hole for screwing the locking nut to the right end part of the rotor shaft are sequentially formed in the belt pulley from left to right along the axial direction, the round table-shaped expansion hole, the middle supporting hole and the operation hole are sequentially communicated, and the radial size of the round table-shaped expansion hole is gradually reduced from left to right.

Preferably, the left end face of the axial limiting sleeve part is abutted against the right end face of the bearing inner ring of the right bearing, and the axial length of the expansion connecting sleeve part is smaller than that of the truncated cone-shaped expansion hole.

The utility model has the beneficial effects that: the fastening effect of the belt pulley is optimized, and the belt pulley is prevented from loosening or falling off on the rotor shaft better;

the difficulty of installation in production is reduced, and the production efficiency is improved;

the disassembly convenience during maintenance is improved, and the maintenance cost is reduced;

under the condition of guaranteeing the quality, the cost is reduced, and the market competitiveness of the product is improved.

Drawings

FIG. 1 is a schematic perspective view of a sleeve in an embodiment;

FIG. 2 is a schematic perspective view of the left side view of the pulley in the embodiment;

FIG. 3 is a schematic perspective view of the right side view of FIG. 2;

FIG. 4 is a schematic perspective view of the pulley assembly of the embodiment shown assembled to a generator;

FIG. 5 is a schematic view of the structure of FIG. 4 in a complete perspective without being broken away;

fig. 6 is a schematic perspective view of the sleeve and pulley according to the embodiment, when the expansion operation is started.

Description of the embodiments

The present utility model will be described in further detail with reference to the accompanying drawings.

The present embodiment is only for explanation of the present utility model and is not to be construed as limiting the present utility model, and modifications to the present embodiment, which may not creatively contribute to the present utility model, may be made by those skilled in the art after reading the present specification, are only protected by patent laws within the scope of the claims of the present utility model.

The utility model relates to a shaft sleeve suitable for an automobile alternating current generator, which comprises an axial limiting sleeve part 11 and an expanding connecting sleeve part 12, wherein the axial limiting sleeve part 11 is sleeved on a rotor shaft z and is used for limiting a belt pulley p in the axial direction, the expanding connecting sleeve part 12 is fixedly connected to the right end of the axial limiting sleeve part 11 in the axial direction and is used for being inserted and expanded with the belt pulley p, the maximum design point of the utility model is that the shaft sleeve is the integration of two functional parts, the axial position of the existing belt pulley on the rotor shaft is realized by depending on an axial limiting retainer ring integrally connected with the left end part of the existing belt pulley on the left side of the belt pulley hub, namely, the side close to the rotor, the left end of the axial limiting retainer ring is abutted against the right end face of a bearing inner ring of a right bearing z2 of a motor, and the existing conical sleeve is arranged on the right side part of the hub of the belt pulley, namely, the hub of the belt pulley is far away from the rotor. The positional relationship of the present embodiment is described with reference to the case where the rotor is viewed from the rear view angle of the left side and the pulley is viewed from the rear view angle of the right side. The utility model is characterized in that the shaft sleeve is arranged on the left side of the hub of the belt pulley when in use, and the belt pulley is an axial limiting retainer ring which is not required to be integrally connected, so that the left side and the right side of the belt pulley are flatter, and the position of the belt pulley on the rotor shaft in the axial direction is realized by the self length blocking of the axial limiting sleeve part 11 of the shaft sleeve. That is, the sleeve of the present utility model is assembled for use in the opposite direction of the pulley. The left end of the axial limiting sleeve part 11 is abutted against the right end face of the bearing inner ring of the right bearing z2, and the expansion connecting sleeve part 12 is inserted into the left side part of the pulley hub for expansion fastening. The original retainer ring of the existing belt pulley is used for adjusting the center wheelbase of the belt pulley and the taper sleeve is expanded between the belt pulley and the shaft so as to obtain two functions of a tighter joint surface, and the two functions are integrated on one shaft sleeve at the same time, so that the structure of the generator belt pulley is simplified to the greatest extent, the fastening effect of the belt pulley is improved, namely, the axial limit retainer ring of the existing belt pulley is combined with the existing taper sleeve and integrated on one shaft sleeve, thus the original retainer ring is transferred, the production cost of the belt pulley can be lowered, the yield of the belt pulley can be higher, the turnover transportation cost can be lowered, the production cost of the shaft sleeve is improved further, the production cost of the taper sleeve is improved somewhat, the process integrated forming is easier for the taper sleeve with a small structure, the influence of the yield is not too great, and in addition, even if the defective rate is improved, the cost is not as great as that of the belt pulley defective products, the control of the cost is better, the subsequent replacement cost is relatively less, the cost is especially easy to damage the whole belt pulley, the whole, the axial limit sleeve 11 or the tight sleeve 12 can be replaced, and the expansion part is quite difficult to replace the existing taper sleeve.

Preferably, the axial stop collar portion 11 is a sleeve body with a C-shaped cross section which can shrink in the radial direction and has cylindrical surfaces on both inner and outer surfaces, the axial stop collar portion 11 is preferably a sleeve structure with an opening, namely, is C-shaped, the cross section is perpendicular to the axial direction of the axial stop collar portion 11, the sleeve body has a certain elastic deformation capability when being C-shaped, and can shrink and reset, and the axial stop collar portion 11, the expansion connecting sleeve portion 12 and the axial direction of the rotor shaft are consistent and extend in the left-right direction. It can be seen that the inner and outer surfaces of the axial stop collar portion 11 are preferably cylindrical surfaces, that is, the inner and outer wall surfaces of the axial stop collar portion 11 are cylindrical surfaces, so that the functionality of the inner surface is better, the expansion connecting sleeve portion 12 deforms and contracts to clamp the rotor shaft when the belt pulley is assembled for expansion, the axial stop collar portion 11 is driven to contract and the inner surface is clamped to the rotor shaft, and therefore, compared with the existing belt pulley retainer ring and taper sleeve combined structure, the axial dimension of the clamped rotor shaft is longer, and the fastening effect of the sleeve to the rotor shaft is better and the stability is higher because the existing belt pulley retainer ring does not clamp the rotor shaft. The outer surface is also a cylindrical surface, so that the thickness of the axial limiting sleeve part 11 is more uniform, the structural strength is better, and the axial stress is more uniform when the position of the belt pulley is determined by limiting axially, so that the belt pulley is safer and more reliable to use.

On the other hand, the expansion connecting sleeve part 12 is a sleeve body which is C-shaped in cross section and can shrink in the radial direction, the inner surface is a cylindrical surface, the outer surface is a conical surface, the outer surface of the expansion connecting sleeve part 12 gradually reduces from left to right in radial dimension, namely, the inner wall surface of the expansion connecting sleeve part 12 is preferably a cylindrical surface so as to better sleeve and hold with a rotor shaft, the outer wall surface is a conical surface and is of a right-side reduced dimension, namely, the right end is a small end, the left end is a large end, and the installation position of the sleeve body is just opposite to that of the prior art, the sleeve body is assembled on the left side part of a pulley hub, namely, the sleeve body is assembled on the side of the pulley hub close to the rotor, and thus, the driving structure is closer to the rotor, and the stress effect is better.

Preferably, the C-shaped opening position of the axial stop collar portion 11 and the C-shaped opening position of the expansion connecting sleeve portion 12 are located at the same circumferential position and are mutually communicated to form a straight shape, so that the whole structure is in a C shape, the axial structure is more symmetrical, and when the expansion connecting sleeve portion 12 is expanded, contracted and deformed with a belt pulley, the expansion connecting sleeve portion 12 can better drive the axial stop collar portion 11 to have a certain contractility so as to be sleeved and held on a rotor shaft.

Further, the inner surfaces of the axial stop collar portion 11 and the inner surface of the expansion connecting sleeve portion 12 are coaxial and have the same radial dimension, that is, the inner surfaces of the axial stop collar portion 11 and the expansion connecting sleeve portion 12 are coplanar, so that the enclasping effect with the sleeving of the rotor shaft is better.

Further preferably, the radial dimension of the outer surface of the axial stop collar portion 11 is smaller than or equal to the maximum radial dimension of the outer surface of the expansion joint sleeve portion 12, it is understood that the diameter of the outer cylindrical surface of the axial stop collar portion 11 is smaller than or equal to the diameter of the outer conical surface of the expansion joint sleeve portion 12 at the joint between the two, because the expansion joint sleeve portion 12 is reduced to the right, the diameter of the fixedly connected part between the outer conical surface of the expansion joint sleeve portion 12 and the axial stop collar portion 11 is the maximum, and the design is such that when the belt pulley is expanded, a certain margin can be left for continuous expansion, and the expanded limit structure can be formed in the belt pulley body.

Also, more importantly, the manufacturing mode of the shaft sleeve of this embodiment may be preferably: the axial stop collar portion 11 and the expansion connecting sleeve portion 12 are cast iron sleeve bodies or steel sleeve bodies or plastic sleeve bodies and are integrally connected and formed, for example, the axial stop collar portion 11 and the expansion connecting sleeve portion 12 can be made of hard plastic, and the following are commonly used: polyethylene, polypropylene, polyvinyl chloride, polytetrafluoroethylene, ABS, organic glass and the like are integrally processed and connected into a whole through forming equipment, and the sleeve body structure is quite silent. Of course, if the steel sleeve body is adopted, the strength is better, and the steel sleeve body can be manufactured and molded through integral casting.

The present embodiment also provides a pulley assembly structure suitable for an automotive alternator, including a pulley p, a rotor shaft z, on which a left bearing z1 and a right bearing z2 are mounted, and a rotor z0 mounted on the rotor shaft z and located between the left bearing z1 and the right bearing z2, the pulley p being mounted at a right end portion of the rotor shaft z, characterized by further including the aforementioned sleeve suitable for an automotive alternator. The sleeve is mounted on the left side of the pulley hub. The method comprises the following steps:

the pulley p is provided with a round table-shaped expansion hole p1 for inserting the expansion connecting sleeve part 12 into the expansion, a middle supporting hole p2 sleeved on the rotor shaft z and an operation hole p3 for screwing the locking nut s to the right end part of the rotor shaft z from left to right in sequence along the axial direction, the round table-shaped expansion hole p1, the middle supporting hole p2 and the operation hole p3 are communicated in sequence, the radial dimension of the round table-shaped expansion hole p1 is gradually reduced from left to right, the round table-shaped expansion hole p1 and the middle supporting hole p2 are formed on a hub of the pulley p, the operation hole p3 is formed on a part of a wheel groove close to the right of the pulley p, the round table-shaped expansion hole p1 and the middle supporting hole p2 are both arranged at the central part of the hub of the pulley p and are coaxial, and the operation hole p3 is coaxial with the hub of the pulley p. The expansion connecting sleeve part 12 is inserted into the circular truncated cone-shaped expansion hole p1 for expansion operation.

Further, the left end face of the axial limiting sleeve part 11 abuts against the right end face of the bearing inner ring of the right bearing z2, and the axial length of the expansion connecting sleeve part 12 is smaller than that of the truncated cone-shaped expansion hole p 1.

The diameter of the middle supporting hole p2 is preferably smaller than the minimum diameter at the right end of the circular truncated cone-shaped expanding hole p1, the minimum diameter at the right end of the circular truncated cone-shaped expanding hole p1 is preferably smaller than the diameter of the operating hole p3, the middle supporting hole p2 and the operating hole p3 are cylindrical, and the middle supporting hole p2 is the smallest-sized hole, so that the pulley hub forms an annular step supporting portion p4 at the periphery of the middle supporting hole p2, and left and right sides of the annular step supporting portion p4 form a left annular supporting surface p41 and a right annular supporting surface p42 respectively. The axial length of the expansion connecting sleeve part 12 is smaller than that of the circular truncated cone-shaped expansion hole p1, so that the right end surface of the expansion connecting sleeve part 12 and the left annular supporting surface p41 can keep a section of axial clearance before expansion, expansion can be successfully completed, the section of clearance is different and is too long, 0.5-1.5mm is controlled, and because the deformation of an axial force application actual shaft sleeve is small, the expansion connecting sleeve part 12 basically expands from an unexpanded state to an expanded state with the fastening effect meeting the requirement, and the expansion can be completed when the axial movement amount is controlled within 0.5 mm. And the lock nut s is screwed against the right side surface of the right annular supporting surface p42.

As an example, in the initial state, the outer surface diameter of the axial stop collar portion 11 is 25mm, the inner surface diameter of the axial stop collar portion 11 is 17mm, the axial length of the axial stop collar portion 11 is 4mm, the maximum diameter of the left end outer surface of the expansion joint sleeve portion 12 is 25mm, the minimum diameter of the right end outer surface is 23mm, the inner surface diameter of the expansion joint sleeve portion 12 is 17mm, the axial length of the expansion joint sleeve portion 12 is 10mm, the maximum diameter of the left side of the circular truncated cone-shaped expansion hole p1 is 25mm, the minimum diameter of the right side is 22.8mm, the axial length of the circular truncated cone-shaped expansion hole p1 is 11mm, the diameter of the middle support hole p2 is 17mm, and the diameter of the operation hole p3 is controlled to be between 30 and 40 mm. Thus, the expansion connecting sleeve portion 12, when ready for expansion just after insertion into the circular truncated cone-shaped expansion hole p1, has an axial movement clearance of 1mm for movement expansion sufficient for expansion to a fastened state.

In the specific assembly process, a left part structure of the generator is firstly assembled, a left bearing z1, a rotor z0, a right bearing z2 and the like are preassembled on the rotor shaft z, then a shaft sleeve of the embodiment is sleeved from the right end of the rotor shaft z and moves leftwards, the left end face of an axial limiting sleeve part 11 abuts against the right end face of a bearing inner ring of the right bearing z2, the expansion connecting sleeve part 12 is arranged on the right side of the axial limiting sleeve part 11, then a belt pulley p is sleeved from the right end of the rotor shaft z and moves leftwards, a circular truncated cone-shaped expansion hole p1 is inserted into the expansion connecting sleeve part 12 and is not expanded, then a locking nut s is placed into an operation hole p3 and moves leftwards at the right end of the rotor shaft z to be screwed, the locking nut s pushes the belt pulley p leftwards against a right annular supporting surface p42, the expansion connecting sleeve part 12 is contracted to perform expansion operation, and in the locking process of the locking nut s, the axial pressure of the belt pulley continuously acts on the conical surface of the expansion connecting sleeve part 12, the opening of the expansion connecting sleeve part 12 is formed on the outer surface of the expansion connecting sleeve part 12, and the pressure of the belt pulley is continuously acts on the rotor shaft and the outer surface of the belt pulley is tightly connected together through the expansion connecting sleeve. The outer surface of the right end part of the rotor shaft z is provided with a thread surface, so that the lock nut can be screwed, a gasket sleeved on the rotor shaft is arranged on the left side of the lock nut s, the gasket is positioned between the right annular supporting surface p42 and the lock nut s, and the gasket is of conventional design for the purpose of operation and structural protection.

After the process is finished, basically, the axial distance between the belt pulley p and the right end face of the bearing inner ring of the right bearing z2 is 3.5-3.9mm, the position of the belt pulley can be effectively controlled according to different fastening requirements, namely, the axial movement amount of the expansion connecting sleeve part 12 in the round table-shaped expansion hole p1 is 0.1-0.5mm in the effective expansion process, the adjustability is better, the operation transformation can be realized according to different vehicle use requirements, and a plurality of vehicle types can be met for use, and of course, the selection on the dimension of the bearing sleeve, the selection of materials and the like can be further met for use under different working conditions.

While the utility model has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions of equivalents may be made and equivalents will be apparent to those skilled in the art without departing from the scope of the utility model. Therefore, the protection scope of the utility model is subject to the protection scope of the claims.

Claims

1. The shaft sleeve is characterized by comprising an axial limiting sleeve part (11) which is sleeved on a rotor shaft (z) and limits a belt pulley (p) in the axial direction, and an expansion connecting sleeve part (12) which is fixedly connected with the right end of the axial limiting sleeve part (11) in the axial direction and is used for being inserted and expanded with the belt pulley (p).

2. A bushing suitable for use in an automotive alternator according to claim 1, wherein the axial stop collar portion (11) is a radially contractible sleeve body having a C-shaped cross section and having cylindrical inner and outer surfaces.

3. A bushing for an automotive alternator according to claim 2, characterized in that the expansion joint sleeve portion (12) is a radially contractible sleeve body having a C-shaped cross section, the inner surface being cylindrical and the outer surface being conical, and the outer surface of the expansion joint sleeve portion (12) is gradually reduced in radial dimension from left to right.

4. A bushing for an automotive alternator according to claim 3, characterized in that the C-shaped opening position of the axial stop collar portion (11) and the C-shaped opening position of the expansion joint sleeve portion (12) are located at the same circumferential position and are communicated with each other in a straight shape.

5. A bushing for an automotive alternator according to claim 3, characterized in that the inner surface of the axial stop collar portion (11) and the inner surface of the expansion connection sleeve portion (12) are concentric and of equal radial dimensions.

6. A bushing suitable for use in an automotive alternator according to claim 3, characterized in that the radial dimension of the outer surface of the axial stop collar portion (11) is less than or equal to the maximum radial dimension of the outer surface of the expansion joint sleeve portion (12).

7. A bushing suitable for use in an automotive alternator according to claim 1, wherein the axial stop collar portion (11) and the expansion joint sleeve portion (12) are cast iron or steel or plastic and are integrally formed.

8. Pulley assembly suitable for automotive alternators, comprising a pulley (p), a rotor shaft (z) fitted with a left bearing (z 1) and a right bearing (z 2) and a rotor (z 0) fitted on the rotor shaft (z) between the left bearing (z 1) and the right bearing (z 2), said pulley (p) being mounted in the right end position of the rotor shaft (z), characterized in that it further comprises a bushing suitable for automotive alternators according to any one of claims 1-7.

9. The pulley assembly structure for the automotive alternator according to claim 8, wherein the pulley (p) is provided with a truncated cone-shaped expansion hole (p 1) for inserting the expansion connecting sleeve portion (12) into the expansion, an intermediate support hole (p 2) sleeved on the rotor shaft (z), and an operation hole (p 3) for screwing the lock nut(s) to the right end portion of the rotor shaft (z) after the lock nut(s) is inserted, the truncated cone-shaped expansion hole (p 1), the intermediate support hole (p 2) and the operation hole (p 3) are sequentially communicated, and the radial dimension of the truncated cone-shaped expansion hole (p 1) is gradually reduced from left to right.

10. Pulley assembly suitable for automotive alternators according to claim 9, characterized in that the left end face of the axial stop collar portion (11) rests on the right end face of the bearing inner ring of the right bearing (z 2), and the axial length of the expansion connection sleeve portion (12) is smaller than the axial length of the truncated cone-shaped expansion hole (p 1).