CN107023585B

CN107023585B - Spline connection structure reaches engine starting motor including it

Info

Publication number: CN107023585B
Application number: CN201610071704.7A
Authority: CN
Inventors: 李剑
Original assignee: Thornger Automotive Parts China Co ltd
Current assignee: Thorne (China) lattice Auto Parts Co., Ltd.
Priority date: 2016-02-02
Filing date: 2016-02-02
Publication date: 2020-11-03
Anticipated expiration: 2036-02-02
Also published as: CN107023585A

Abstract

The invention relates to a spline connection structure and an engine starting motor comprising the same. The spline connection structure includes: the first spline is positioned on the first circumferential surface and comprises first key teeth and blocking teeth, the first key teeth are uniformly distributed on the first circumferential surface along the circumferential direction, a first key groove is formed between the adjacent first key teeth, and the blocking teeth are positioned at one end of the first key teeth and are aligned with at least one first key groove; and a second spline located on the second circumferential surface and adapted to engage with the first spline, the second spline having second spline teeth and a missing tooth portion adapted to pass the blocking tooth when assembled, when the first spline is engaged with the second spline and corresponding second spline teeth of the second spline are inserted into the at least one first spline groove, a ratio of working teeth of the first spline adapted to interact with the second spline is greater than 1: 2. the invention has the advantages of higher working efficiency and reliability.

Description

Spline connection structure reaches engine starting motor including it

Technical Field

The invention relates to the technical field of mechanical connection structures; in particular, the present invention relates to a spline connection structure. Further, the invention also relates to an engine starting motor comprising the spline connection structure.

Background

Generally, a spline connection structure is composed of an internal spline and an external spline, and is commonly used for connection between shaft holes. The inner and outer splines are multi-tooth parts, the splines on the inner cylindrical surface of the bore are inner splines and the splines on the outer cylindrical surface of the shaft are outer splines.

According to different classifications, the splines may include rectangular splines, triangular splines, involute splines, and the like; or include straight splines, helical splines, and the like.

Fig. 1 shows a cross-sectional view and a plan development of a helical spline of the prior art. In fig. 3, the internal spline 1 is provided with 7 splines 3 and the external spline 2 is provided with 14

splines

4 and 7 dog teeth 5 at one end of the splines. In the working process of the internal spline and the external spline, because the number of the spline teeth is limited, the stress borne by each spline tooth is large, and the spline teeth are easy to damage to cause spline failure. As shown in fig. 2 and 3, the wearing parts 6, 7 of the internal spline and the external spline of the conventional helical spline in the isolator of the starter motor of the automobile engine are shown. In addition, since only the inner spline teeth on one side of the outer spline teeth function when torque is transmitted, the utilization rate of the spline teeth is not high.

Disclosure of Invention

It is an object of the present invention to provide a splined connection which overcomes the aforementioned drawbacks of the prior art.

Further, it is also an object of the present invention to provide an engine starting motor including such a spline connection structure.

In order to achieve the foregoing technical object, a first aspect of the present invention provides a spline connection structure for shaft hole fitting, wherein the spline connection structure comprises:

a first spline on a first circumferential surface, the first spline including first key teeth and a retaining tooth, the first key teeth being evenly distributed circumferentially on the first circumferential surface and forming a first key slot between adjacent first key teeth, the retaining tooth being located at one end of the first key teeth and aligned with at least one of the first key slots; and

a second spline on the second circumferential surface and adapted to engage the first spline, the second spline having a second spline tooth thereon and a missing tooth portion adapted to pass the dog tooth therethrough when assembled,

wherein, when the first spline is engaged with the second spline and corresponding second spline teeth of the second spline are inserted into the at least one first spline groove, a ratio of working teeth of the first spline adapted to interact with the second spline is greater than 1: 2.

alternatively, in the spline connection structure as described above, the first spline is a driving spline and the second spline is a driven spline, or the first spline is a driven spline and the second spline is a driving spline.

Alternatively, in the spline connection structure as described above, the first circumferential surface is an inner circumferential surface of the hole and the second circumferential surface is an outer circumferential surface of the shaft, or the first circumferential surface is an outer circumferential surface of the shaft and the second circumferential surface is an inner circumferential surface of the hole.

Optionally, in the spline connection structure as described above, the spline connection structure is a helical spline connection structure.

Optionally, in the spline connection structure, the blocking teeth are uniformly distributed on the first circumferential surface along the circumferential direction, each blocking tooth is distributed to different M first key teeth and is aligned with at most N adjacent first key grooves, wherein M is greater than 2, and N is less than M; and is

The number of the tooth lacking portions is the same as that of the tooth blocking portions, the second key teeth are defined by the tooth lacking portions and are grouped, each group of the second key teeth are suitable for being respectively matched in the first key grooves among the different M first key teeth, and the tooth pitch of the tooth lacking portions is at least 1 time of N plus of the tooth pitch of the first spline.

Optionally, in the spline connection structure as described above, each set of the second key teeth includes at most M minus N second key teeth.

Optionally, in the spline connection structure as described above, N is equal to 1, each group of the second key teeth includes M minus 1 second key teeth, and the pitch of the second key teeth within each group is equal to the pitch of the first key teeth.

Optionally, in the spline connection structure as described above, the teeth of the blocking teeth uniformly distributed on the first circumferential surface in the circumferential direction have missing teeth, and/or each group of the second key teeth have missing teeth.

In order to achieve the foregoing technical object, a second aspect of the invention provides an engine starter motor including a spline connection structure as set forth in any one of the foregoing first aspects.

Alternatively, in the starter motor as described above, the starter motor includes an isolator and a pinion shaft driven by the isolator, the pinion shaft drives an engine flywheel through a pinion, and

the first spline of the spline connection structure is positioned on the one-way device and the second spline is positioned on the pinion shaft, or the second spline of the spline connection structure is positioned on the one-way device and the first spline is positioned on the pinion shaft.

Drawings

The disclosure of the present invention will be more apparent with reference to the accompanying drawings. It is to be understood that these drawings are solely for purposes of illustration and are not intended as a definition of the limits of the invention. In the figure:

FIG. 1 shows a cross-sectional view and a plan expanded view of a prior art helical spline;

FIGS. 2 and 3 show the wear of the internal and external splines of a conventional helical spline in a one-way clutch for an engine starter motor of an automobile; and

fig. 4 shows a cross-sectional view and an expanded plan view of a helical spline according to an embodiment of the present invention.

Detailed Description

Specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same or corresponding features.

FIG. 4 illustrates a cross-sectional view and a plan expanded view of a spline connection structure according to an embodiment of the present invention. The spline connection structure is used for shaft hole matching; specifically, in the illustrated example, a pinion shaft for an engine starter motor is fitted to a shaft hole of an inner hole of the isolator. It is understood that the pinion shaft and the isolator of the engine starter motor are only used as an illustration here; the spline connection structure is also suitable for shaft hole connection in other occasions.

As shown in fig. 4 (1), a cross-sectional view of the spline connection structure. As shown, the spline connection structure is adapted for engagement of a first circumferential surface 10 and a second circumferential surface 20, one of which is an outer circumferential surface of a shaft and the other of which is an inner circumferential surface of a bore.

As can be seen from the figure, in the particular example shown, the first circumferential surface 10 is the outer circumferential surface of the shaft and the second circumferential surface 20 is the inner circumferential surface of the bore. More specifically, the shaft may be a pinion shaft of an engine starting motor, and the bore may be an inner bore of a isolator of the engine starting motor. In the engine starting motor, a rotor of the engine starting motor drives a pinion shaft through a one-way clutch in a spline connection structure, and the pinion shaft supplies power to a flywheel of an automobile engine through the pinion, so that the engine is started. It can be seen that in this embodiment, the splines on the inner bore of the isolator (i.e., the second splines) are the driving splines, while the splines on the pinion shaft (i.e., the first splines) are the driven splines.

Given the teachings of the present disclosure, those skilled in the art will appreciate that in other applications, it is also contemplated that the first spline may be configured as a driven spline and the second spline may be configured as a driving spline; alternatively, the first circumferential surface may be provided as an inner circumferential surface of the hole and the second circumferential surface may be provided as an outer circumferential surface of the shaft.

Development of the spline connection structure is shown in fig. 4, (2) and (3). As can be seen from the figure, the spline connection structure is a spiral spline connection structure. It will be appreciated that the spline connection structure according to the present invention is equally applicable to a straight spline connection structure and the like.

As can be seen more clearly in the figures, the splined connection comprises a first spline on the first circumferential surface 10, the first spline comprising a first spline tooth 11 and a dog tooth 12. The first key teeth are circumferentially evenly distributed on the first circumferential surface and form first key grooves 13 between adjacent first key teeth. The dog tooth 12 is located at one end of the first key tooth and is aligned with the at least one first key slot. In the figure, the blocking teeth 12 are also circumferentially evenly distributed on the first circumferential surface; however, in alternative embodiments, the blocking teeth 12 may also be missing, for example, only one, two or three of the illustrated blocking tooth positions. As long as the catch has sufficient strength, as few catch teeth as possible can be used to reduce the manufacturing difficulty and cost.

The splined connection further comprises a second spline on the second circumferential surface 20 adapted to engage the first spline, which may have a second spline tooth 21 and a missing tooth portion 22 adapted to pass a dog tooth when assembled. Where the second splines are adapted to engage the first splines, it is contemplated that their configuration of teeth, keyways, etc. may be uniform in shape, size, or may be adjusted by one skilled in the art to match the two.

In the illustrated example, when the pinion shaft (shown at the first spline) is installed in the hole of the one-way clutch, the missing tooth part of the second spline can be aligned with the blocking tooth of the first spline, and the second spline of the pinion shaft can be completely inserted along the first keyway; after the insertion, the pinion shaft is rotated by a certain angle, the second key teeth of the second spline are retracted into the key grooves between the first key teeth, at least one second key tooth is aligned with the blocking teeth, and therefore when the second spline slides outwards, the second spline can be blocked by the blocking teeth and cannot be separated from the isolator.

Fig. 4 (2) and (3) show different operating positions of one embodiment of the helical spline connection according to the invention, respectively.

In fig. 4 (2), the helical spline connection is in the rest position of the starter motor. At this time, the starter motor does not perform the starting operation of the engine, and the second spline is engaged with and held to the right of the first spline. On the right side of the second spline, it is prevented from slipping out to the right due to a stopper such as a collar, not shown, mounted on the pinion shaft. When the starter motor starts to work, the second spline drives the first spline along the circumferential direction. Due to the oblique arrangement of the helical splines, the first spline and the second spline will simultaneously generate relative displacement in the axial direction until the key teeth of the second spline abut against the blocking teeth, as shown in fig. 4 (3). In this state, the pinion on the pinion shaft will engage the flywheel of the engine, starting the vehicle engine. After the engine is started, the rotation speed of the pinion shaft is driven by the engine to gradually exceed the rotation speed of the isolator, so that the pinion shaft gradually returns to the position in (2) of fig. 4 along the axial direction, finally, the pinion is separated from the engine flywheel, and the engine starting operation is finished.

As shown in fig. 4, in this embodiment, when the first spline is engaged with the second spline and the corresponding second spline teeth of the second spline are slip-fitted within the at least one first spline, the ratio of working teeth of the first spline adapted to interact with the second spline is greater than 1: 2. specifically, in this example, the first spline includes 16 first spline teeth 11 and the second spline includes 12 second spline teeth 21. Of the 16 first splines, only 12 on a single side of the second spline interact with the second spline, and it can be seen that the ratio of working teeth in the first spline that are adapted to interact with the second spline is 3: 4, greater than 1: 2. at the moment, compared with the prior art, the working efficiency and the reliability of the spline connection structure are improved.

Further variations will occur to those skilled in the art based on the examples in the figures. For example, each dog tooth may be assigned to a different number M of first key teeth and align up to N adjacent first key slots therein, where M is greater than 2, N is less than M, and M and N are integers. The number of the toothless portions may be the same as or more than the number of the toothless portions to be suitable for the toothless portions to pass by when the gear is assembled. As shown in fig. 4 (2) and (3), the second key teeth may be grouped by being defined by missing tooth portions, with each group of second key teeth adapted to fit within the first key grooves between different M first key teeth, respectively. In order to ensure that the blocking tooth can pass through the missing tooth part, the tooth pitch of the missing tooth part can be at least 1 times the tooth pitch N of the first spline. Each set of second key teeth may then include up to M minus N second key teeth. It should be further noted that, in order to achieve better working efficiency and reliability, on the basis of the aforementioned values of M and N, it is simultaneously ensured that the ratio of the working teeth of the first spline which act on the second spline is greater than 1: 2.

for example, when M is 4 and N is 1, the technical scheme of the present invention in fig. 4 can be obtained. At this time, each of the blocking teeth may be assigned to 4 different first key teeth and aligned with 1 of the first key grooves; the number of the tooth missing parts is the same as that of the gear blocking parts, and the number of the tooth missing parts is 4; the second key teeth can be divided into groups defined by the tooth missing parts, and each group of second key teeth are suitable for being respectively matched in the first key grooves among the 4 different first key teeth; in order to ensure that the blocking teeth can pass through the tooth-lacking part, the tooth pitch of the tooth-lacking part is 2 times of the tooth pitch of the first spline; each set of second key teeth includes 3 second key teeth. At this time, the ratio of the working teeth of the first spline, which function with the second spline, is 3: 4, greater than 1: 2.

for another example, another technical solution can be obtained when M is 5 and N is 2. At this time, each of the blocking teeth may be assigned to 5 different first key teeth and aligned with 2 adjacent ones of the first key grooves; the number of the tooth missing parts can be the same as that of the gear stopping parts; the second key teeth can be divided into groups defined by the tooth missing parts, and each group of second key teeth are suitable for being respectively matched in the first key grooves among 5 different first key teeth; in order to ensure that the blocking teeth can pass through the tooth-lacking part, the tooth pitch of the tooth-lacking part is 3 times of the tooth pitch of the first spline; each set of second key teeth includes 3 second key teeth. At this time, the ratio of the working teeth of the first spline, which function with the second spline, is 3: 5, greater than 1: 2.

for another example, when M is 3 and N is 1, another technical scheme can be obtained. At this time, each of the blocking teeth may be assigned to 3 different first key teeth and aligned with 2 first key grooves therein; the number of the tooth missing parts is the same as that of the gear blocking parts; the second key teeth can be divided into groups defined by the tooth missing parts, and each group of second key teeth are suitable for being respectively matched in the first key grooves among different 3 first key teeth; in order to ensure that the blocking teeth can pass through the tooth-lacking part, the tooth pitch of the tooth-lacking part is 2 times of the tooth pitch of the first spline; each set of second key teeth includes 2 second key teeth. At this time, the ratio of the working teeth of the first spline which act on the second spline is 2: 3, greater than 1: 2.

as can be seen from the above, in an alternative embodiment, N may also be equal to 1, each set of second key teeth includes M minus 1 second key teeth, and the pitch between the second key teeth within each set may be equal to the pitch of the first key teeth. It will be appreciated that M and N may take on other suitable integer values, not to mention one example.

In addition, in an alternative embodiment, the blocking teeth uniformly distributed on the first circumferential surface along the circumferential direction may have missing teeth, and each group of second key teeth may also have missing teeth. In the case where there is a missing tooth in the latch, as long as the strength of the remaining missing tooth is sufficient, it is possible to achieve a situation in which the second spline is prevented from disengaging from the first spline. It is also conceivable, in the case of missing second key teeth, to ensure that the working tooth ratio of the first key teeth of the splined connection is greater than 1: 2, still more reliable technical effect can be obtained compared with the prior art, and the requirements of the invention are met.

From the above description, those skilled in the art will appreciate that the spline connection structure according to the present invention can be applied to an engine starter motor. In one example, such a starter motor may include a one-way clutch and a pinion shaft driven by the one-way clutch, the pinion shaft may drive an engine flywheel through a pinion gear thereon, and the one-way clutch and the pinion shaft are engaged through a splined connection of the present invention. In an alternative embodiment, the first splines of the splined connection are located on the one-way clutch and the second splines are located on the pinion shaft, or the second splines of the splined connection are located on the one-way clutch and the first splines are located on the pinion shaft.

The technical scope of the present invention is not limited to the above description, and those skilled in the art can make various changes and modifications to the above-described embodiments without departing from the technical spirit of the present invention, and such changes and modifications should fall within the scope of the present invention.

Claims

1. The utility model provides a be used for shaft hole complex spline connection structure which characterized in that, spline connection structure includes:

2. the splined connection of claim 1, wherein the first spline is a driving spline and the second spline is a driven spline, or the first spline is a driven spline and the second spline is a driving spline.

3. The spline connection structure according to claim 1, wherein the first circumferential surface is an inner circumferential surface of a hole and the second circumferential surface is an outer circumferential surface of a shaft, or the first circumferential surface is an outer circumferential surface of a shaft and the second circumferential surface is an inner circumferential surface of a hole.

4. The spline connection structure of claim 1, wherein the spline connection structure is a helical spline connection structure.

5. The spline connection structure according to any one of claims 1 to 4,

the blocking teeth are uniformly distributed on the first circumferential surface along the circumferential direction, each blocking tooth is distributed to different M first key teeth and is aligned with at most N adjacent first key grooves, wherein M is larger than 2, and N is smaller than M; and is

6. The splined connecting structure of claim 5, wherein each set of the second key teeth comprises up to M minus N second key teeth.

7. The splined connecting structure of claim 6, wherein N is equal to 1, each set of the second key teeth comprises M minus 1 second key tooth, and the pitch of the second key teeth within each set is equal to the pitch of the first key teeth.

8. The spline connection structure according to claim 5, wherein the blocking teeth evenly distributed along the circumferential direction on the first circumferential surface have missing teeth, and/or each group of the second key teeth have missing teeth.

9. An engine starter motor characterized by comprising a spline connection structure as recited in any one of the preceding claims 1 to 8.

10. The starter motor of claim 9, wherein the starter motor includes an isolator and a pinion shaft driven by the isolator, the pinion shaft driving an engine flywheel through a pinion, and