CN117869567A - Speed reducer, electric drive system and automobile - Google Patents

Abstract

The invention provides a speed reducer, an electric driving system and an automobile, and relates to the technical field of automobile parts. In the scheme of the invention, the annular gear is matched with the shell through the locating sleeve, compared with the existing scheme of directly processing the bulge on the inner wall of the shell to be matched with the groove on the annular gear, the shell is simpler to process because the shell does not need to be provided with structures such as the processing bulge, a machine tool with lower precision can be directly adopted for processing the shell, the locating sleeve can be processed by adopting the traditional gear processing technology, the dependence on a high-precision machine tool is greatly reduced, and the overall processing cost is lower.

Description

Speed reducer, electric drive system and automobile

Technical Field

The invention relates to the technical field of automobile parts, in particular to a speed reducer, an electric driving system and an automobile.

Background

The mileage of a new energy vehicle is an important index for evaluating the performance of the new energy vehicle, in order to arrange more batteries in a limited space, the arrangement space of an electric drive system is continuously compressed, the miniaturization of the electric drive system such as a speed reducer becomes a development trend, and the coaxial speed reducer has the advantage of occupying a small space, so that the application is becoming wider and wider.

The coaxial reducer generally comprises a shell and a planetary gear set, wherein the planetary gear set comprises an annular gear, external spline teeth are arranged on the peripheral wall of the annular gear, an internal spline groove is integrally formed on the inner wall of the shell, and the annular gear and the shell are assembled through the cooperation of the external spline teeth and the internal spline groove. However, in order to ensure torque transmission stability and impact toughness between the ring gear and the housing, the grooves of the inner wall of the housing are usually required to be processed by a high-precision five-axis numerical control machining center, and the whole housing is required to be made of a high-strength material, so that the processing cost of the speed reducer is high.

Disclosure of Invention

The invention aims to solve the technical problem of higher processing cost of the existing speed reducer.

In a first aspect, the invention provides a speed reducer, which comprises a shell, a positioning sleeve and an inner gear ring, wherein the outer peripheral wall of the positioning sleeve is matched with the inner peripheral wall of the shell in shape, the positioning sleeve is arranged in the shell and is matched with the inner peripheral wall of the positioning sleeve, the inner peripheral wall of the positioning sleeve is provided with a clamping part, the outer peripheral wall of the inner gear ring is provided with a clamping matching part matched with the clamping part, and the inner gear ring is matched with the positioning sleeve through the clamping part and the clamping matching part.

Compared with the prior art, the speed reducer has at least the following advantages:

the clamping fit portion on the outer peripheral wall of the inner gear ring is matched with the clamping fit portion on the inner peripheral wall of the positioning sleeve, the outer peripheral wall of the positioning sleeve is matched with the inner peripheral wall of the shell, so that the inner spline groove is machined on the inner peripheral wall of the inner gear ring, compared with the traditional scheme that the inner spline groove is machined on the inner wall of the shell directly, the outer spline tooth on the inner gear ring is matched with the positioning sleeve, and the inner peripheral wall of the inner gear ring is assembled together after being formed separately, namely the inner peripheral wall of the shell is free from machining structures such as the inner spline groove, the shell can be machined by a four-axis machine tool or a three-axis machine tool with lower precision, the inner peripheral wall of the positioning sleeve is provided with the clamping fit portion to form a similar inner spline groove structure, the traditional gear machining process can be adopted for machining, dependence on a high-precision five-axis machining center is greatly reduced, and the overall machining cost is lower. In addition, the locating sleeve is an independent part, and can only adopt materials with higher strength to meet the repeated impact requirement of the annular gear, compared with the prior art that the whole shell adopts materials with higher strength, the cost can be further reduced, so that the speed reducer or the coaxial speed reducer can be widely applied to various vehicle types with different grades, and the market competitiveness is improved.

Optionally, the clamping portion includes an inner spline groove disposed on an inner peripheral wall of the positioning sleeve, and the clamping mating portion includes an outer spline tooth disposed on an outer peripheral wall of the ring gear, and the outer spline tooth is used for being inserted into the inner spline groove.

Optionally, the inner peripheral wall of the shell is provided with a limiting step surface, and the axial end surface of the positioning sleeve and the axial end surface of the annular gear are both abutted to the limiting step surface.

Optionally, the speed reducer further comprises a pressing plate and a fastening piece, wherein one end face, far away from the limiting step face, of the annular gear ring protrudes axially to form an annular positioning boss, a positioning hole penetrating axially is formed in the pressing plate, the pressing plate is used for being sleeved on the positioning boss through the positioning hole, the radial size of the pressing plate is larger than that of the annular gear ring, and the edge portion, beyond the annular gear ring, of the pressing plate is used for being connected with the positioning sleeve through the fastening piece.

Optionally, the periphery wall of clamp plate is equipped with along radial outside first engaging lug that extends, be equipped with first connecting hole on the first engaging lug, the periphery wall of spacer sleeve is equipped with radial outside second engaging lug that extends, be equipped with the second connecting hole on the second engaging lug, first connecting hole with the second connecting hole corresponds the setting, the fastener is used for passing in proper order first connecting hole with the second connecting hole.

Optionally, a third connecting hole communicated with the first connecting hole and the second connecting hole is formed in the limiting step surface, and the fastener is used for penetrating through the first connecting hole, the second connecting hole and the third connecting hole in sequence.

Optionally, the outer peripheral wall of the positioning sleeve is in interference fit with the inner peripheral wall of the housing.

Optionally, the positioning sleeve is made of a surface strengthening treatment or a high-strength material.

In a second aspect, the present invention proposes an electric drive system comprising a decelerator as described above. Compared with the prior art, the electric drive system has the same advantages as the speed reducer and is not repeated.

In a third aspect, the present invention provides an automobile comprising the electric drive system described above. Compared with the prior art, the automobile has the same advantages as the electric drive system, and the description is omitted.

Drawings

FIG. 1 is an exploded view of a reduction gear unit according to an embodiment of the present invention;

FIG. 2 is a schematic view of a positioning sleeve and a pressing plate according to an embodiment of the present invention;

fig. 3 is a partial cross-sectional view of a decelerator of an embodiment of the present invention.

Reference numerals illustrate:

1. a housing; 11. limiting step surfaces; 12. a third connection hole; 2. a positioning sleeve; 21. a clamping part; 22. a second connection hole; 3. an inner gear ring; 31. a clamping matching part; 32. positioning the boss; 4. a pressing plate; 41. positioning holes; 42. a first connection hole; 5. a fastener.

Detailed Description

In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

In the description of the present invention, unless explicitly stated and limited otherwise, the terms "mounted," "connected," "coupled," and "mated" are to be construed broadly, and may be, for example, fixedly coupled, detachably coupled, or integrally coupled; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those skilled in the art according to the specific circumstances.

In addition, in the description of the present invention, it should be noted that terms such as "upper", "lower", "front", "rear", etc. in the embodiments indicate terms of orientation, and only for simplifying the positional relationship of the description based on the drawings of the specification, it does not represent that the elements and devices etc. referred to must be operated according to the operations and methods and configurations defined in the specific orientation and limitation of the present invention, and such orientation terms do not constitute limitations of the present invention.

A Y-axis is established herein, wherein the Y-axis represents a left-right direction, a forward direction of the Y-axis represents a left direction, and a reverse direction of the Y-axis represents a right direction. It should also be noted that the foregoing Y-axis is provided merely for the purpose of describing the present invention and for simplicity of description, and is not intended to indicate or imply that the devices or elements referred to must be in a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.

As shown in fig. 1-3, an embodiment of the present invention provides a speed reducer, including a casing 1, a positioning sleeve 2 and an inner gear ring 3, where the outer peripheral wall of the positioning sleeve 2 is matched with the inner peripheral wall of the casing 1 in shape, the positioning sleeve 2 is disposed in the casing 1 and is mounted in cooperation with the inner peripheral wall of the positioning sleeve 2, the inner peripheral wall of the positioning sleeve 2 is provided with a clamping portion 21, the outer peripheral wall of the inner gear ring 3 is provided with a clamping mating portion 31 matched with the clamping portion 21, and the inner gear ring 3 is mounted in cooperation with the positioning sleeve 2 through the clamping portion 21 and the clamping mating portion 31.

Specifically, the inside cavity of casing 1, and one end is equipped with the opening, inside casing 1 was put into to spacer bush 2, ring gear 3 from the open end of casing 1, spacer bush 2 is annular, spacer bush 2, ring gear 3 and casing 1 three coaxial setting. The engaging portion 21 may be a groove or a protrusion, and the engaging mating portion 31 may be a protrusion or a groove. The inner peripheral wall of the inner gear ring 3 is provided with a tooth structure which can be meshed with the planet gears.

In this embodiment, the clamping matching portion 31 on the outer peripheral wall of the ring gear 3 is matched with the clamping portion 21 on the inner peripheral wall of the positioning sleeve 2, so that the outer peripheral wall of the positioning sleeve 2 is matched with the inner peripheral wall of the housing 1, and the matching installation between the ring gear 3 and the housing 1 is realized. In addition, the locating sleeve 2 is an independent part, and can only adopt materials with higher strength to meet the repeated impact requirement of the annular gear, compared with the existing shell which is integrally made of materials with higher strength or integrally made of surface strengthening treatment, the cost can be further reduced, so that the speed reducer or the coaxial speed reducer can be widely applied to vehicle types with various grades, and the market competitiveness is improved.

As shown in fig. 1-2, alternatively, the clamping portion 21 includes an inner spline groove provided on an inner peripheral wall of the positioning sleeve 2, and the clamping mating portion 31 includes external spline teeth provided on an outer peripheral wall of the ring gear 3 for insertion into the inner spline groove.

Specifically, a plurality of internal spline grooves are circumferentially arranged on the inner peripheral wall of the positioning sleeve 2 at intervals, a plurality of external spline teeth are circumferentially arranged on the outer peripheral wall of the inner gear ring 3 at intervals, the shapes of the external spline teeth are matched with those of the internal spline grooves, and the radial positioning of the inner gear ring 3 relative to the positioning sleeve 2 is realized by utilizing the matching of the external spline teeth and the internal spline grooves. The shape of the inner spline groove and the outer spline tooth comprises common shapes such as rectangular spline, involute spline and the like; but are not limited thereto and include other shapes that can transmit axial forces. The distribution of the inner spline grooves on the positioning sleeve 2 and the distribution of the outer spline teeth on the ring gear 3 may be equal or unequal.

In other embodiments, a plurality of external spline teeth may be circumferentially arranged on the inner peripheral wall of the positioning sleeve 2 at intervals, and a plurality of internal spline grooves may be circumferentially arranged on the outer peripheral wall of the ring gear 3 at intervals, so that the positioning sleeve 2 and the ring gear 3 are radially positioned by matching the external spline teeth with the internal spline grooves.

As shown in fig. 1 and 3, optionally, the inner peripheral wall of the housing 1 is provided with a limiting step surface 11, and the axial end surface of the positioning sleeve 2 and the axial end surface of the annular gear 3 are both abutted against the limiting step surface 11.

Specifically, the casing 1 is far away from open-ended one end and can be provided with a limit step face 11, limit step face 11 is echelonment along the axis direction, can include the one-level step face that connects gradually, junction surface and second grade step face, the junction surface sets up along being on a parallel with the axis direction of casing 1, one-level step face, second grade step face sets up along the axis direction of perpendicular to casing 1, one-level step face and second grade step face are annular face, the inward flange of one-level step face is connected with the outward flange of second grade step face through the junction surface, the axial one end of position sleeve 2 is the second grade echelonment to with each face butt of limit step face 11 respectively, the one end of ring gear 3 and the second grade step face butt of limit step face 11.

In other embodiments, the limiting step surface 11 may be replaced by a plane, and the axial end surfaces of the inner gear ring 3 and the positioning sleeve 2 simultaneously abut against the plane.

In the embodiment, the positioning sleeve 2 is abutted with the limiting step surface 11 of the inner peripheral wall of the shell 1 so as to realize axial installation and positioning between the positioning sleeve 2 and the shell 1, and the annular gear 3 is abutted with the limiting step surface 11 of the inner peripheral wall of the shell 1 so as to realize axial positioning and assembly between the annular gear 3 and the shell 1.

As shown in fig. 1 and 3, optionally, the speed reducer further includes a pressing plate 4 and a fastener 5, an end surface of the ring gear 3 away from the limiting step surface 11 protrudes axially to form an annular positioning boss 32, a positioning hole 41 penetrating axially is formed in the pressing plate 4, the pressing plate 4 is sleeved on the positioning boss 32 through the positioning hole 41, a radial dimension of the pressing plate 4 is greater than a radial dimension of the ring gear 3, and an edge portion of the pressing plate 4 beyond the ring gear 3 is connected with the positioning sleeve 2 through the fastener 5.

Specifically, the pressing plate 4 may be an annular plate structure, the positioning boss 32 may be integrally formed with the inner gear ring 3, the positioning boss 32 is an annular boss, and a tooth slot is formed inside the positioning boss and may be engaged with the planet gear. The fastener 5 may be a bolt, a connecting rod, or the like.

In this embodiment, the fastening member 5 passes through the circumferential edge of the pressing plate 4 and the positioning sleeve 2 to press the ring gear 3 against the positioning sleeve 2, so as to realize axial locking of the two, and limit the ring gear 3 from being separated from the positioning sleeve 2 along the axial direction.

The prior art generally sets up first annular groove through the middle part of the outer peripheral wall of ring gear, sets up the second annular groove at the middle part of the inner peripheral wall of casing, and first annular groove and second annular groove are gone into to the snap ring card simultaneously to avoid the ring gear to break away from the casing along the axial, but adopt this kind of mode because the interior outer wall of snap ring needs to cooperate with two annular grooves simultaneously, the assembly process degree of difficulty is big, generally needs manual assembly, the holistic assembly cost of reduction gear is higher. In this embodiment, the pressing plate 4 is matched with the positioning boss 32 on the axial end surface of the inner gear ring 3, the pressing plate 4 is fastened with the positioning sleeve 2 by the fastener 5, the assembly is easier, and the robot automatic assembly can be adopted, so that the overall assembly cost of the reducer is reduced.

As shown in fig. 1-2, optionally, a first connecting lug extending outwards along a radial direction is provided on the outer peripheral wall of the pressing plate 4, a first connecting hole 42 is provided on the first connecting lug, a second connecting lug extending outwards along a radial direction is provided on the outer peripheral wall of the positioning sleeve 2, a second connecting hole 22 is provided on the second connecting lug, the first connecting hole 42 and the second connecting hole 22 are correspondingly arranged, and the fastener 5 is used for penetrating through the first connecting hole 42 and the second connecting hole 22 in sequence.

Specifically, the first engaging lugs may be disposed at intervals along the circumferential edge of the pressing plate 4, the first engaging lugs are provided with first engaging holes 42 penetrating along the axial direction parallel to the ring gear 3, the second engaging lugs are disposed in one-to-one correspondence with the first engaging lugs, the second engaging lugs are disposed at intervals along the circumferential edge of the positioning sleeve 2, the second engaging lugs are provided with second engaging holes 22 penetrating along the axial direction parallel to the positioning sleeve 2, the first engaging holes 42 and the second engaging holes 22 may be threaded holes, and the fastening member 5 may be a bolt. Here, each second connection lug is smooth in circumferential wall surface and is located on the same circumference, and each second connection lug is in contact with the inner circumferential wall of the housing 1.

In this embodiment, the fastening members 5 sequentially pass through the corresponding first connecting holes 42 and the second connecting holes 22 to fix the pressing plate 4 and the positioning sleeve 2, that is, to realize the axial locking of the ring gear 3. The plurality of first connecting holes 42 and the plurality of second connecting holes 22 are arranged along the circumferential direction, and the plurality of fasteners 5 distributed at intervals along the circumferential direction are adopted to fix the pressing plate 4 and the positioning sleeve 2, so that the stress is more uniform, and the stability of the speed reducer in operation is better.

As shown in fig. 1, optionally, the limiting step surface 11 is provided with a third connecting hole 12 that is in communication with the first connecting hole 42 and the second connecting hole 22, and the fastener 5 is used to sequentially pass through the first connecting hole 42, the second connecting hole 22, and the third connecting hole 12.

Specifically, the third connecting hole 12 may be a blind hole, and may be disposed on the second step surface of the limiting step surface 11, where the third connecting hole 12 is disposed along the direction parallel to the axis of the housing 1, the third connecting hole 12 is disposed corresponding to the second connecting hole 22, and two axial ends of the second connecting hole 22 are respectively communicated with the first connecting hole 42 and the third connecting hole 12.

In this embodiment, the fastening member 5 passes through the first connecting hole 42, the second connecting hole 22 and the third connecting hole 12, so as to fix the pressing plate 4, the positioning sleeve 2 and the housing 1, improve the installation stability of the pressing plate 4 and the positioning sleeve 2, and improve the axial locking effect on the ring gear 3.

Optionally, the outer peripheral wall of the positioning sleeve 2 is in interference fit with the inner peripheral wall of the housing 1.

In this embodiment, a part of the outer peripheral wall of the positioning sleeve 2 is in interference fit with the inner peripheral wall of the housing 1, or the whole outer peripheral wall of the positioning sleeve 2 is in interference fit with the inner peripheral wall of the housing 1, so that a tight fit is formed between the positioning sleeve 2 and the housing 1, and the connection strength and rigidity between the positioning sleeve 2 and the housing 1 are ensured.

Illustratively, when the outer circumferential wall of the positioning sleeve 2 is provided with a second connecting lug extending outwards in the radial direction, the inner circumferential wall of the housing 1 is provided with a clamping groove matched with the shape of the second connecting lug; like this, both can guarantee that the outer peripheral wall of spacer sleeve 2 with the interior perisporium shape matching and interference fit of casing 1 makes spacer sleeve 2 and casing 1 spacing each other in the circumference again, is favorable to the reliability of the fixed connection of spacer sleeve 2 and casing 1.

Optionally, the positioning sleeve 2 is made of a surface strengthening treatment, or the positioning sleeve 2 is made of a high-strength material.

In this embodiment, the positioning sleeve 2 may be subjected to surface strengthening treatment by anodic oxidation or the like, or ultra-high strength alloy steel is adopted, so that the positioning sleeve 2 can maintain good impact toughness and strength when the internal gear ring 3 and the positioning sleeve 2 repeatedly impact in forward and reverse rotation of the speed reducer.

Another embodiment of the present invention provides an electric drive system including the above-mentioned decelerator. The electric drive system has the same advantages as the above-described decelerator over the prior art, and the description thereof will not be repeated.

A further embodiment of the invention provides an automobile comprising the electric drive system. The advantages of the vehicle over the prior art are the same as those of the electric drive system described above and will not be repeated.

Although the invention is disclosed above, the scope of the invention is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications will fall within the scope of the invention.

Claims (10)

1. The utility model provides a reduction gear, its characterized in that, includes casing (1), spacer sleeve (2) and ring gear (3), the periphery wall of spacer sleeve (2) with the interior perisporium shape phase-match of casing (1), spacer sleeve (2) are arranged in casing (1) and both cooperation installation, the interior perisporium of spacer sleeve (2) is equipped with joint portion (21), be equipped with on the periphery wall of ring gear (3) with joint portion (21) assorted joint cooperation portion (31), ring gear (3) are through joint portion (21) with joint cooperation portion (31) with the cooperation installation of spacer sleeve (2).

2. The speed reducer according to claim 1, wherein the snap-fit portion (21) includes an inner spline groove provided on an inner peripheral wall of the positioning sleeve (2), and the snap-fit portion (31) includes an outer spline tooth provided on an outer peripheral wall of the ring gear (3) for insertion into the inner spline groove.

3. The speed reducer according to claim 1, wherein the inner peripheral wall of the housing (1) is provided with a limiting step surface (11), and the axial end surface of the positioning sleeve (2) and the axial end surface of the annular gear (3) are both abutted against the limiting step surface (11).

4. A reducer according to claim 3, further comprising a pressing plate (4) and a fastener (5), wherein an end face of the annular gear ring (3) far away from the limiting step face (11) protrudes axially to form an annular positioning boss (32), a positioning hole (41) penetrating axially is formed in the pressing plate (4), the pressing plate (4) is used for being sleeved on the positioning boss (32) through the positioning hole (41), the radial dimension of the pressing plate (4) is larger than that of the annular gear ring (3), and the edge part of the pressing plate (4) beyond the annular gear ring (3) is used for being connected with the positioning sleeve (2) through the fastener (5).

5. The speed reducer according to claim 4, wherein the outer peripheral wall of the pressing plate (4) is provided with a first connecting lug extending outwards along a radial direction, the first connecting lug is provided with a first connecting hole (42), the outer peripheral wall of the positioning sleeve (2) is provided with a second connecting lug extending outwards along a radial direction, the second connecting lug is provided with a second connecting hole (22), the first connecting hole (42) and the second connecting hole (22) are correspondingly arranged, and the fastener (5) is used for sequentially penetrating through the first connecting hole (42) and the second connecting hole (22).

6. The speed reducer according to claim 5, wherein the limiting step surface (11) is provided with a third connecting hole (12) communicated with the first connecting hole (42) and the second connecting hole (22), and the fastener (5) is used for penetrating through the first connecting hole (42), the second connecting hole (22) and the third connecting hole (12) in sequence.

7. A reducer according to claim 1, wherein the outer peripheral wall of the positioning sleeve (2) is in interference fit with the inner peripheral wall of the housing (1).

8. A reducer according to claim 1, characterized in that the positioning sleeve (2) is surface-hardened or the positioning sleeve (2) is made of a high-strength material.

9. An electric drive system comprising a decelerator according to any one of claims 1-8.

10. An automobile comprising the electric drive system of claim 9.