CN111852716A

CN111852716A - Shifting fork rotation center positioning structure and starter comprising same

Info

Publication number: CN111852716A
Application number: CN202010704195.3A
Authority: CN
Inventors: 洪文灿; 崔湛; 崔银奎; 崔泽
Original assignee: Hebei Junda Automobile Electrical Appliances Co ltd
Current assignee: Hebei Junda Automobile Electrical Appliances Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2020-10-30

Abstract

The invention discloses a shifting fork rotation center positioning structure and a starter, wherein the structure comprises a front cover and a shifting fork, the front cover is provided with two opposite fixed clamping pins, a gap for the shifting fork to pass through is formed between the two fixed clamping pins, the middle part of the shifting fork is correspondingly provided with two convex shafts, and each fixed clamping pin is provided with a clamping groove for the convex shaft to insert; the front cover is provided with a shifting fork. Insert the protecgulum draw-in groove with the shift fork protruding shaft during assembly, the degree of freedom of shift fork rotation center all directions has been restricted to the cooperation cushion, it is rotatory around rotation center only to allow it, the installation is reliable, avoid appearing inefficacy hidden danger, the round pin seat has been cancelled, replace the function direct design of round pin seat with the fixing clip foot on the protecgulum, compact structure, reduce part quantity and occupation space, protruding shaft direct design replaces the function of round pin axle on the shift fork, reduce installation interface and assembly step, the production efficiency is improved, reduce to the minimum with the volume and the material use amount of shift fork and protecgulum corresponding part to the at utmost, the cost is reduced, easy to assemble.

Description

Shifting fork rotation center positioning structure and starter comprising same

Technical Field

The invention relates to the technical field of starters, in particular to a shifting fork rotation center positioning structure and a starter comprising the same.

Background

The starter plays a role that an automobile engine must rotate by means of external force before running under self power, wherein a shifting fork is one of important components of the starter. As shown in fig. 1, which is a partial schematic view of a positioning structure of a rotation center of a starter fork in the prior art, a fork 4 includes an upper fulcrum 4a, a middle fulcrum 4b and a lower fulcrum 4 c. Wherein, the middle pivot 4b is the rotation center of the shifting fork 4. When a driver turns a key door switch to a Start gear, a coil of the electromagnetic switch 1 is electrified and attracted, a movable iron core 2 moves rightwards along the direction indicated by an arrow, a pull rod 3 on the movable iron core 2 pulls an upper supporting point 4a of a shifting fork 4, the shifting fork 4 rotates clockwise around a supporting point 4b, and therefore a lower supporting point 4c of the shifting fork 4 pushes a one-way clutch 10, an output shaft 11 on the one-way clutch 10 and a pinion 12 to push the output shaft and the pinion 12 leftwards along the direction indicated by the arrow and engage in a flywheel gear ring 13 of an engine. After the main contact of the electromagnetic switch 1 is closed, the motor 8 is electrified to rotate to drive the speed reducing mechanism 9, the speed reducing mechanism 9 drives the output shaft 11 of the isolator 10 and the pinion 12, the pinion 12 drives the flywheel gear ring 13 to rotate until the ignition speed of the engine is reached, and the engine is ignited successfully. Wherein the middle pivot 4b of the shifting fork 4 is arranged in the middle hole of the rotating pin seat 5, and the rotating pin seat 5 is tightly pressed in the hole of the front cover 7 by the cushion block 6.

In the prior art, the fork 4 generally takes two designs. In the first solution, as shown in fig. 2, the fork 4 and the rotating pin seat 5 are respectively of an integral structure, and the middle fulcrum 4b, i.e. the cylindrical pillow block on both sides of the fork 4, and the fork 4 are also integrally formed. The middle fulcrums 4b on the two sides are symmetrically arranged and protrude out of the surface of the shifting fork 4. When the front cover is assembled, the two middle supporting points 4b of the shifting fork 4 slide in from the slots 5a of the rotating pin seat 5, then the two pins 5c of the rotating pin seat 5 need to be greatly deformed outwards until the middle supporting points 4b extend into the insertion holes 5b of the rotating pin seat 5, and then the two pins 5c of the rotating pin seat 5 need to return to ensure that the diameter of the outer circle of the two pins does not change greatly so as to be installed in the hole of the front cover 7.

However, this places severe demands on the strength and toughness of the material of the tumbler pins 5. If the strength is too strong, the two pins 5c of the rotating pin base 5 are deformed outward to a limited extent, and the two middle fulcrums 4b of the shift fork 4 cannot easily slide from the slot 5a into the insertion holes 5 b. After the worker presses in with great power, two participate in 5c and can take place plastic deformation, can't return completely, and its excircle diameter changes greatly, can't install in the hole of protecgulum 7, and it is very inconvenient to install. If the strength is too low, the toughness is insufficient, and the two pins 5c of the rotating pin base 5 may be broken in the process of outward deformation, so that the rotating pin base 5 is scrapped, or fine cracks are generated in the deformation process and cannot be detected by workers, and the two pins fail in the subsequent starter working process.

As shown in fig. 3, in the second solution, the shift fork 4 is composed of two shift fork pieces and a pin, and the middle parts of the two shift fork pieces are provided with middle holes for mounting the pin. During assembly, the middle holes of the two shifting fork pieces are aligned with the insertion holes 5b on the two pins 5c of the rotating pin seat 5, and the pin shaft is inserted to form a middle fulcrum 4 b. Meanwhile, the upper supporting point 4a, the middle supporting point 4b and the lower supporting point 4c of the two shifting forks 4 are ensured to be respectively aligned.

Although the kingpin boss 5 does not have a risk of failure as in the first solution, the number of parts and the number of mounting interfaces are large and the production cost is high. Moreover, the two insertion holes 5b of the rotating pin seat 5 and the middle holes of the two shifting fork pieces need to be penetrated by the same pin shaft, so that the operation is inconvenient. Meanwhile, the pin shaft is in clearance fit with the holes, and the shifting fork 4 is easy to fall off when being taken and installed, so that the working time is very delayed.

In addition, in the two solutions, the rotating pin base 5 occupies a large space, so that the hole of the front cover 7 for accommodating the rotating pin base 5 also occupies a large space, resulting in that the front cover 7 consumes more material at the position, which increases the cost and the volume.

Therefore, how to solve the problems of the prior art, such as large number of parts and parts interfaces, high cost, inconvenient installation, low production efficiency, large volume of corresponding parts of the shifting fork and the front cover, and large material consumption, is an important technical problem to be solved by those skilled in the art.

Disclosure of Invention

The invention aims to provide a shifting fork rotation center positioning structure and a starter comprising the same, and aims to solve the problems that in the prior art, the number of parts and the number of part interfaces are large, the cost is high, the installation is inconvenient, the production efficiency is reduced, and the corresponding installation parts of a shifting fork and a front cover are large in size and large in material consumption.

The purpose of the invention is realized by the following technical scheme:

the invention provides a shifting fork rotation center positioning structure which comprises a front cover and a shifting fork, wherein the front cover is provided with two fixing clamping pins which are oppositely arranged, a gap for the shifting fork to pass through is formed between the two fixing clamping pins, the middle part of the shifting fork is provided with convex shafts which are convexly arranged and respectively correspond to the fixing clamping pins one by one, each fixing clamping pin is provided with a clamping groove which is matched with the convex shaft and used for the convex shaft to insert, and the clamping groove is arranged along the axial direction of the fixing clamping pin; the shifting fork is pressed on the front cover through a cushion block.

Preferably, the front cover is provided with a first protruding part which is arranged between the two fixing clamping feet and extends into the gap, and the first protruding part and the cushion block are used for abutting against the outer wall of the shifting fork so as to limit the shifting fork between the first protruding part and the cushion block.

Preferably, each one side that the draw-in groove is kept away from the cushion is equipped with and is used for blocking the fender body of protruding axle, the cushion be equipped with the draw-in groove cooperatees and stretches into the second bellying in the draw-in groove, keep off the body with the second bellying is used for supporting the outer wall of protruding axle, with the protruding axle restriction is in keep off the body with between the second bellying.

Preferably, the number of the second protruding parts is two, and the second protruding parts correspond to the clamping grooves one to one.

Preferably, at the middle position of the shifting fork, both a first outer contour of the shifting fork opposite to the front cover and a second outer contour of the shifting fork opposite to the cushion block are arc-shaped.

Preferably, the diameter of the first outer contour is the same as the diameter of the second outer contour, and the center of the circle of the first outer contour and the center of the circle of the second outer contour coincide with the center of the convex shaft.

Preferably, the two fixing clamping feet and the front cover are of an integrated structure, and the two protruding shafts and the shifting fork are of an integrated structure.

Preferably, the shifting fork is of an integrated structure, and the two protruding shafts are symmetrically arranged on two sides of the shifting fork.

Preferably, the shifting fork is made of plastic, and the two protruding shafts and the shifting fork are formed by integral injection molding.

Preferably, the shifting fork is of a split structure and comprises a first half body and a second half body which are arranged oppositely, and the protruding shafts are respectively arranged on one sides, facing the clamping grooves, of the first half body and the second half body.

Preferably, the first half body and the second half body are made of cold-rolled plates and are formed by blanking and bending, and the two protruding shafts are respectively formed by cold heading and protruding from the surfaces of the first half body and the second half body.

Preferably, the material of the cushion block is low-carbon steel or low-carbon cold-rolled plate.

Preferably, the material of the cushion block is high-carbon steel, pre-hardened plate or low-carbon steel after heat treatment.

The invention also provides a starter which comprises the shifting fork rotating center positioning structure.

According to the technical scheme provided by the invention, the shifting fork rotation center positioning structure comprises a front cover and a shifting fork, wherein the front cover is provided with two fixing clamping pins which are oppositely arranged, a gap for the shifting fork to pass through is formed between the two fixing clamping pins, the middle part of the shifting fork is provided with convex shafts which are convexly arranged and respectively correspond to the fixing clamping pins one by one, each fixing clamping pin is provided with a clamping groove which is matched with the convex shaft and used for the convex shaft to insert, and the clamping groove is arranged along the axial direction of the fixing clamping pin; the front cover is provided with a front cover and a rear cover, and the front cover is provided with a cushion block for pressing the shifting fork on the front cover. By the arrangement, the convex shaft of the shifting fork is inserted into the clamping groove of the front cover, the freedom degree of the shifting fork in each direction of the rotation center is limited by matching with the cushion block, only the shifting fork is allowed to rotate around the rotation center, the installation is very convenient, the potential failure hazard is avoided, the rotary pin seat is eliminated, the function of replacing the rotary pin seat by the fixed clamping pin is directly designed on the front cover, the structure is compact, the number of parts and the occupied space are reduced, the protruding shaft is directly designed on the shifting fork, the function of a pin shaft is replaced, the installation interface and the assembly steps are reduced, the working hour is saved, the production efficiency is improved, the volume and the material usage amount of corresponding positions of the shifting fork and the front cover are reduced to the minimum to the greatest extent, the cost is reduced, the installation is convenient, and the problems that in the prior art, the number of parts and the number of part interfaces are large, the cost is high, the installation is inconvenient, the production efficiency is reduced, the volume of the corresponding positions of the shifting fork and the front cover is large, and the material usage amount is large are solved.

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 described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a partial schematic view of a prior art fork rotation center positioning structure;

FIG. 2 is a first schematic view of the prior art assembly of a shift fork and a rotating pin base;

FIG. 3 is a second schematic view illustrating the assembly of a shift fork and a pivot pin seat in the prior art;

FIG. 4 is a partial schematic view of a positioning structure of a rotational center of a shift fork according to an embodiment of the present invention;

FIG. 5 is a partial schematic view of a portion A of FIG. 4 according to a first embodiment of the present invention;

FIG. 6 is a partial schematic view of a front cover in accordance with a first embodiment of the present invention;

FIG. 7 is a schematic view of a shifting fork of a split structure according to an embodiment of the present invention;

FIG. 8 is a partial cross-sectional view of the first half of FIG. 7 taken at the center of the convex axis;

FIG. 9 is a schematic view of a shift fork of an integrated structure according to an embodiment of the present invention;

FIG. 10 is a partial schematic view taken at A in FIG. 4 according to a second embodiment of the present invention;

FIG. 11 is a partial schematic view of a front cover in a second embodiment of the present invention;

FIG. 12 is a schematic view of a second embodiment of a spacer according to the present invention.

In fig. 1-3:

1-an electromagnetic switch; 2-a movable iron core; 3-a pull rod; 4-a shifting fork; 4 a-upper fulcrum; 4 b-a middle fulcrum; 4 c-lower fulcrum; 5-rotating the pin seat; 5 a-slot; 5 b-a jack; 5 c-pin; 6-cushion block; 7-front cover; 8, a motor; 9-a speed reducing mechanism; 10-a one-way clutch; 11-an output shaft; 12-a pinion gear; 13-flywheel ring gear.

In fig. 4-12:

1-an electromagnetic switch; 2-a movable iron core; 3-a pull rod; 4-a shifting fork; 4 a-upper fulcrum; 4 b-a middle fulcrum; 41-protruding shaft; 42-a first outer contour; 43-a second outer contour; 44-a first half; 45-a second half; 6-cushion block; 61-a second boss; 7-front cover; 71-fixing clamping pins; 72-card slot; 73-stepped bore; 74-first boss; 75-a baffle; 76-center plane.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. The embodiments described below do not limit the contents of the invention recited in the claims. The entire contents of the configurations shown in the following embodiments are not limited to those required as solutions of the inventions described in the claims.

Referring to fig. 4-12, the fork rotation center positioning structure of the present embodiment includes a front cover 7 and a fork 4, wherein the front cover 7 has two opposite fixing pins 71. Alternatively, as shown in fig. 6, the fixing clip leg 71 is cylindrical, the outer wall of the fixing clip leg is arc-shaped, and the outer walls of the two fixing clip legs 71 are located on the circumference of the same diameter. The two fixing clip feet 71 are symmetrically arranged about a central plane 76, and a gap for the shifting fork 4 to pass through is formed between the two fixing clip feet, and it should be noted that the central plane 76 is a plane formed by a central line of the motor 8 and a central line of the electromagnetic switch 1. The middle part of the shifting fork 4 is provided with a convex shaft 41 which protrudes out of the surface of the shifting fork 4 and is in one-to-one correspondence with each fixed clamping foot 71, namely a middle pivot 4b is formed, and the center of the convex shaft 41 is the rotation center of the shifting fork 4. Each fixing clip leg 71 is provided with a clip groove 72 which is matched with the protruding shaft 41 and is used for inserting the protruding shaft 41, and the clip groove 72 is arranged along the axial direction of the fixing clip leg 71. It should be noted that fig. 6 is a partial structural schematic view of the front cover as viewed from right to left in fig. 4, and a direction perpendicular to the paper plane in fig. 6 is an axial direction of the fixing clip, and correspondingly, a left-right direction in fig. 4 is an axial direction of the fixing clip. As shown in fig. 6, the two side engaging grooves 72 are oppositely disposed to match the gap between the two fixing engaging legs 71, and a recessed cross-shaped groove structure is formed in the space, thereby limiting the freedom of the rotation center of the shift fork 4. Simultaneously, shift fork rotation center location structure still includes and is used for pressing the cushion 6 on protecgulum 7 with shift fork 4. As shown in fig. 6, a stepped hole 73 is formed at one end of the front cover 7 close to the pad 6, i.e., at the rear side of the front cover 7 in the drawing, and the pad 6 is seated in the stepped hole 73, thereby further limiting the front and rear degrees of freedom of the rotation center of the shift fork 4. Up to this point, the degrees of freedom of the center of the shift fork 4, such as up, down, left, right, front and rear, are all limited, and can only rotate around the rotation center. By the arrangement, the convex shaft of the shifting fork is inserted into the clamping groove of the front cover, the freedom degree of the shifting fork in each direction of the rotation center is limited by matching with the cushion block, only the shifting fork is allowed to rotate around the rotation center, the installation is very convenient, the potential failure hazard is avoided, the rotary pin seat is eliminated, the function of replacing the rotary pin seat by the fixed clamping pin is directly designed on the front cover, the structure is compact, the number of parts and the occupied space are reduced, the protruding shaft is directly designed on the shifting fork, the function of a pin shaft is replaced, the installation interface and the assembly steps are reduced, the working hour is saved, the production efficiency is improved, the volume and the material usage amount of corresponding positions of the shifting fork and the front cover are reduced to the minimum to the greatest extent, the cost is reduced, the installation is convenient, and the problems that in the prior art, the number of parts and the number of part interfaces are large, the cost is high, the installation is inconvenient, the production efficiency is reduced, the volume of the corresponding positions of the shifting fork and the front cover is large, and the material usage amount is large are solved.

In the first embodiment, as shown in fig. 6, the front cover 7 is provided with a first protrusion 74 disposed between the two fixing clips 71 and extending into the gap. As shown in fig. 5, the first boss 74 and the block 6 cooperate for abutting against the outer wall of the fork 4, thereby trapping the fork 4 between the first boss 74 and the block 6. Wherein, the cushion block 6 is of a flat plate structure and is placed in the stepped hole 73. The shifting fork is arranged in such a way that the outermost side of the whole shifting fork is abutted between the front cover and the cushion block, and the convex shaft is supported in the clamping groove and can rotate. In a preferred embodiment of the present invention, as shown in fig. 5, at the middle position of the shift fork 4, the first outer contour 42 of the shift fork 4 opposite to the front cover 7 and the second outer contour 43 of the shift fork 4 opposite to the cushion block 6 are both circular arcs, which are beneficial to the rotational movement of the shift fork center, specifically, the diameter of the first outer contour 42 is the same as that of the second outer contour 43, both the diameters are D1, that is, the first outer contour 42 and the second outer contour 43 are located on the same circle with the diameter D1, and the circle centers of the first outer contour 42 and the second outer contour 43 coincide with the center of the protruding shaft 41. For convenience of installation, the protruding shaft 41 should be in clearance fit in all directions, so in this embodiment, as shown in fig. 5, the distance L1 between the first protruding portion 74 and the pad 6 is slightly larger than the maximum distance between the two outer walls of the shift fork 4, i.e. the diameter D1, e.g. 0mm < L1-D1 < 1mm, so as to avoid the outer wall of the shift fork 4 from being deadly pushed and not rotating, and ensure that the freedom of the shift fork rotation center to move back and forth cannot be too large; meanwhile, the distance L2 between the upper end and the lower end of the clamping groove 72 is slightly larger than the outer diameter D2 of the protruding shaft 41, for example, 0mm is larger than L2-D2 is smaller than 1mm, so that the protruding shaft 41 can be conveniently arranged in the clamping grooves 72 on the two sides, and the freedom degree of the shifting fork in up-and-down movement of the rotation center cannot be too large.

In the second embodiment, as shown in fig. 11, a side of each of the locking grooves 72 away from the spacer 6, that is, a front side of the locking groove 72, is provided with a stopper 75 for stopping the protruding shaft 41. As shown in fig. 12, the spacer 6 is provided with a second protrusion 61 which is engaged with the locking groove 72 and extends into the locking groove 72. Specifically, the second protruding portions 61 are two, are arranged in one-to-one correspondence with the notches 72, and are symmetrical with respect to the central plane 76. As shown in fig. 10, the stopper 75 and the second projection 61 cooperate to abut against the outer peripheral wall of the protruding shaft 41, thereby trapping the protruding shaft 41 between the stopper 75 and the second projection 61. Set up like this, the protruding axle periphery wall supports between retainer and second bellying, prevents that shift fork back-and-forth movement scope is too big, and the protruding axle still supports in the draw-in groove and can rotate simultaneously. In a preferred embodiment of the present invention, as shown in fig. 10, at the middle position of the shift fork 4, the first outer contour 42 of the shift fork 4 opposite to the front cover 7 and the second outer contour 43 of the shift fork 4 opposite to the spacer 6 are also circular arcs, specifically, the diameter of the first outer contour 42 is the same as that of the second outer contour 43, both of which are D1, that is, the first outer contour 42 and the second outer contour 43 are located on the circumference of the same diameter D1, and the circle centers of the first outer contour 42 and the second outer contour 43 coincide with the center of the protruding shaft 41. Of course, the first outer contour 42 and the second outer contour 43 may be flat or have other shapes, so as to ensure the strength of the positions and avoid interference with the inner wall of the front cover 7 and the end face of the cushion block 6 in the rotation range. For convenience of installation, the protruding shaft 41 should be clearance-fit in all directions, so in this embodiment, as shown in fig. 10, the distance L6 between the blocking body 75 and the second protrusion 61 and the distance L2 between the upper end and the lower end of the slot 72 are slightly larger than the outer diameter D2 of the protruding shaft 41, so as to prevent the outer wall of the protruding shaft 41 from being locked and unable to rotate, and ensure that the freedom of the shifting fork rotation center to move back and forth cannot be too large. Meanwhile, in order to ensure that the middle part of the shifting fork 4 has enough moving space when the protruding shaft 41 rotates, the distance L5 between the inner wall of the front cover 7 and the end surface of the cushion block 6 is larger than the maximum distance between the two outer walls of the shifting fork 4, namely the diameter D1. In addition, the length L7 of the second projecting portion 61 should be determined by comprehensively considering the sizes of L5, L6, and the like in design. The height L10 of the second protrusions 61 should be less than L2, such as 0mm < L2-L10 < 1mm, and the distance L8 between the outer sides of the two second protrusions 61 should be less than the distance L3 between the bottoms of the two slots 72, such as 0mm < L3-L8 < 1mm, so as to ensure that the second protrusions 61 can be conveniently installed in the slots 72. The distance L9 between the inner sides of the two second protrusions 61 is enough for the fork 4 to move, so that the second protrusions 61 can be inserted into the slots 72, thereby effectively limiting the moving range of the protruding shaft 41.

In the present embodiment, the two fixing clips 71 are integrated with the front cover 7, and the two protruding shafts 41 are integrated with the fork 4. In actual processing, the fixing clamping feet 71 and the front cover 7 are directly formed by die drawing, so that the forming is convenient and fast, and the production efficiency is improved. Meanwhile, the protruding shaft 41 directly extrudes or extrudes on the shifting fork 4 from the surface of the shifting fork 4 in an injection molding mode to replace a pluggable pin shaft, the secondary assembly is not needed, the number of parts is reduced, the assembly time is shortened, and the operation is convenient.

As an alternative embodiment, the shift fork 4 is an integral structure, and the two protruding shafts 41 are symmetrically arranged on two sides of the shift fork 4. Specifically, the material of the shift fork 4 is plastic, such as reinforced nylon or other plastic with certain strength and toughness, and is formed by integral injection molding. Meanwhile, the two protruding shafts 41 and the shifting fork 4 are also formed by integral injection molding, and are directly injected on the shifting fork 4 and symmetrically protrude out of the surface of the shifting fork 4 from two sides. In order to facilitate the fork 4 to be placed in the gap between the two fixed clamping legs 71, as shown in fig. 9, the distance L3 between the bottoms of the two clamping grooves 72 is slightly greater than the distance L4 between the outer end faces of the two protruding shafts 41, for example, 0mm < L3-L4 < 1mm, so that the protruding shafts 41 can be conveniently installed in the clamping grooves 72 on both sides, the problems of deformation and failure of parts due to inconvenient installation are avoided, and the degree of freedom of movement of the fork in the left-right direction is ensured not to be too large; at this time, the gap between the two fixing clips 71, i.e. L3 ', is slightly larger than the distance L4' between the two side surfaces of the shift fork 4, for example, L3 '-L4' > 1mm, and the over-positioning in the left-right direction cannot be formed. In addition, if the protruding shaft 41 contacts the second protrusion 61, the distance L9 between the inner sides of the second protrusions 61 should be slightly larger than the distance L4' between the two sides of the fork 4.

In other embodiments, the shift fork 4 is a split structure, and the shift fork 4 includes a first half 44 and a second half 45 that are disposed opposite to each other, and the protruding shafts 41 are respectively disposed on the sides of the first half 44 and the second half 45 facing the engaging groove 72. Specifically, the first half body 44 and the second half body 45 are made of cold-rolled plates and are formed by punching and bending, and the two protruding shafts 41 are respectively formed by cold heading and protruding from the surfaces of the first half body 44 and the second half body 45. As shown in fig. 7, the two half bodies are respectively processed, and the upper fulcrum 4a, the middle fulcrum 4b and the lower fulcrum 4c are aligned during combination, so that the shifting fork 4 can reliably work. The two half bodies can be fixed together through welding, riveting and the like, and can also realize the function of simultaneously rotating the two half bodies without being connected together. As shown in fig. 7, the two half bodies are symmetrically arranged, the thickness of each half body is L4', the thickness of the middle pivot point 4b position provided with the protruding shaft 41 is L4, so that the distance L3 between the bottoms of the two slots 72 is slightly more than twice L4, for example, 0mm < L3-2L 4 < 1mm, so that the protruding shaft 41 can be conveniently installed in the slots 72 on both sides after the two shifting fork half bodies are overlapped, and the freedom degree of the shifting fork moving in the left-right direction can not be too large; at this time, the size of the gap between the two fixing clips 71, i.e., L3 ', is more than twice L4', e.g., L3 '-2 × L4' > 1mm, and thus the over-positioning cannot be formed in the left-right direction. In addition, if the protruding shaft 41 contacts the second protrusion 61, the distance L9 between the inner sides of the second protrusions 61 should be slightly larger than twice L4'.

Since the shifting fork 4 continuously rolls the cushion block 6 during the operation of the starter, there may be a situation that the cushion block 6 is rolled to be deformed or rolled through. The shifting fork 4 material of integral type structure is plastics, has certain self-lubricating function, therefore the material of the cushion 6 of its complex is low carbon steel or low carbon cold-rolled sheet, and its intensity is higher than the intensity of plastics, can satisfy corresponding operation requirement. The shifting fork 4 with the split structure is made of a cold-rolled sheet, so that the cushion block 6 matched with the cold-rolled sheet is made of high-carbon steel, pre-hardened sheet or heat-treated low-carbon steel, the strength of the shifting fork is higher than that of the cold-rolled sheet, and the durability of the cushion block 6 is enhanced. If the material of the cushion block 6 is also a cold-rolled sheet, the cushion block is easily rolled and deformed or penetrated by the shifting fork 4.

The embodiment also provides a starter, which comprises the shifting fork rotation center positioning structure. So set up, provide a part quantity few, part interface quantity few, with low costs, easy to assemble, reduce the volume and the material use amount's of shift fork and protecgulum corresponding part location form of location to reduce cost improves the reliability, improves production efficiency. The beneficial effect derivation process of the starter is substantially similar to that of the shifting fork rotation center positioning structure, and therefore, the description is omitted here.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The shifting fork rotation center positioning structure is characterized by comprising a front cover (7) and a shifting fork (4), wherein the front cover (7) is provided with two fixing clamping pins (71) which are oppositely arranged, a gap for the shifting fork (4) to pass through is formed between the two fixing clamping pins (71), the middle part of the shifting fork (4) is provided with convex shafts (41) which are convexly arranged and respectively correspond to the fixing clamping pins (71) one by one, each fixing clamping pin (71) is provided with a clamping groove (72) which is matched with the convex shaft (41) and is used for inserting the convex shaft (41), and the clamping groove (72) is arranged along the axial direction of the fixing clamping pin (71); the shifting fork mechanism further comprises a cushion block (6) used for pressing the shifting fork (4) on the front cover (7).

2. A fork rotation center positioning structure according to claim 1, wherein the front cover (7) is provided with a first boss (74) provided between the two fixing catches (71) and extending into the gap, the first boss (74) and the pad (6) being adapted to abut against an outer wall of the fork (4) to restrain the fork (4) between the first boss (74) and the pad (6).

3. A fork rotation center positioning structure according to claim 1, wherein a side of each of the engaging grooves (72) away from the spacer (6) is provided with a stopper (75) for stopping the protruding shaft (41), the spacer (6) is provided with a second protrusion (61) which is engaged with the engaging groove (72) and extends into the engaging groove (72), and the stopper (75) and the second protrusion (61) are adapted to abut against an outer wall of the protruding shaft (41) to restrain the protruding shaft (41) between the stopper (75) and the second protrusion (61).

4. A fork rotation center positioning structure according to claim 3, wherein the second protrusions (61) are two and correspond to the catching grooves (72) one to one.

5. A fork rotation center positioning structure according to claim 1, wherein at a middle position of the fork (4), a first outer contour (42) of the fork (4) opposite to the front cover (7) and a second outer contour (43) of the fork (4) opposite to the pad (6) are both circular arc-shaped.

6. A fork rotation center positioning structure according to claim 5, wherein the diameter of the first outer contour (42) and the diameter of the second outer contour (43) are the same, and the centers of the first outer contour (42) and the second outer contour (43) coincide with the center of the protruding shaft (41).

7. A fork rotation center positioning structure according to claim 1, wherein the two fixing catches (71) are integrally formed with the front cover (7), and the two protruding shafts (41) are integrally formed with the fork (4).

8. A fork rotation center positioning structure according to claim 7, wherein the fork (4) is a one-piece structure, and the two shafts (41) are symmetrically disposed on both sides of the fork (4).

9. A fork rotation center positioning structure according to claim 8, wherein the fork (4) is made of plastic, and the two shafts (41) and the fork (4) are formed by integral injection molding.

10. A fork rotation center positioning structure according to claim 7, wherein the fork (4) is a split structure, and the fork (4) comprises a first half body (44) and a second half body (45) which are oppositely arranged, and the side of the first half body (44) and the side of the second half body (45) facing the clamping groove (72) are respectively provided with the protruding shaft (41).

11. A shift fork rotation center positioning structure according to claim 10, wherein the first half body (44) and the second half body (45) are made of cold rolled plate and are formed by blanking and bending, and the two protruding shafts (41) are respectively formed by cold heading and protruding from the surfaces of the first half body (44) and the second half body (45).

12. A fork rotation center positioning structure according to claim 9, wherein the material of the spacer (6) is low carbon steel or low carbon cold rolled sheet.

13. A fork rotation center positioning structure according to claim 11, wherein the material of the spacer (6) is high carbon steel, pre-hardened plate, or heat-treated low carbon steel.

14. A starter comprising the fork rotation center positioning structure according to any one of claims 1 to 13.