CN216742504U - Power transmission device, electric drive assembly system and vehicle - Google Patents

Abstract

Disclosed is a power transmission device including: a first shaft extending along a central axis and provided with a bore comprising a first end section, a second end section, and an internally splined section between the first and second end sections, the first end section being disposed proximate to a tip of the first shaft; a second shaft comprising an externally splined section corresponding to the internally splined section; wherein an annular groove is provided on an inner wall of the first end section, a first oil storage space is formed between the annular groove and the second shaft, a second oil storage space is formed at the second end section, and a flow passage is provided between the first oil storage space and the second oil storage space, the flow passage extending from an inlet in the first oil storage space to an outlet in the second oil storage space in a manner of being away from the central axis. An electric drive assembly system is also disclosed, which comprises the power transmission device. A vehicle is also disclosed that includes an electric drive assembly system.

Description

Power transmission device, electric drive assembly system and vehicle

Technical Field

The utility model relates to a power transmission device, including power transmission device's electric drive assembly system and vehicle including electric drive assembly system.

Background

A pair of shafts with complementary splines, for example with internal and external splines, respectively, may be splined for power transmission. When the splines are exposed to humid air, the splines may rust very easily, affecting the efficiency of the power transmission, and even making it necessary to replace the shaft. Therefore, it is necessary to apply lubricating grease at the spline coupling portions to ensure that the splines do not rust, and thus to ensure the service life of the shaft and even the power transmission device including the shaft, and to effectively reduce noise. However, if there is no seal at the spline coupling portion, the lubricating grease will leak due to high-speed rotation, affecting the lubricating effect, and the lubricating grease may also be affected by external dirt.

At present, one prior art solution to this problem involves the use of sealing rings to seal the splined interface, however, often accompanied by vibrations during high speed rotation of the shaft, experiments have shown that such sealing rings will thus irreversibly deform or even break damage, leading to seal failure, causing grease leakage to be severe, affecting the operation of the entire device, and possibly causing irreversible loss of alignment.

The utility model discloses aim at solving the problem that exists among the above-mentioned prior art with simple and compact structure.

SUMMERY OF THE UTILITY MODEL

To this end, according to an aspect of the present invention, there is provided a power transmission device including: a first shaft extending along a central axis, the first shaft provided with a bore extending along the central axis, the bore including a first end section, a second end section, and an internally splined section between the first and second end sections, the first end section disposed proximate a tip of the first shaft; a second shaft extending along the central axis and including an externally splined section corresponding to the internally splined section; wherein an annular groove is provided on an inner wall of the first end section, a first oil storage space is formed between the annular groove and the second shaft, a second oil storage space is formed at the second end section, and a flow passage is provided between the first oil storage space and the second oil storage space, the flow passage extending from an inlet in the first oil storage space to an outlet in the second oil storage space in a manner of being away from the central axis.

That is, in the proposed power transmission device according to the present invention, the second shaft will be inserted into the inner bore of the first shaft, and the externally splined section of the second shaft will engage with the internally splined section of the first shaft, so that the first shaft and the second shaft can rotate together to transmit power between each other. Thus, the inner bore of the first shaft should be open at the end of the first shaft to be able to receive the second shaft. Furthermore, the second end section of the inner bore of the first shaft itself forms a second oil sump space, i.e. the inner bore of the first shaft in this second end section may be provided blind or blind, thereby forming a space which may be used for storing lubricating grease for lubricating the internally and externally splined sections, i.e. the second oil sump space. The first end section of the inner bore of the first shaft is then disposed near the end of the first shaft. In this case, it is necessary to ensure that the lubricating grease does not leak from the second oil reservoir space to the outside through the inter-coupled male and female spline sections and then through the distal end of the first shaft. For this reason, according to the utility model discloses, be provided with the ring channel on the inner wall of the first end district section of the hole of primary shaft, form first oil storage space between this ring channel and the secondary shaft, be provided with the runner between this first oil storage space and second oil storage space, the entry setting of runner is in first oil storage space, the export of runner then sets up in second oil storage space, then the runner is set up to extend in order to keep away from the mode of central axis from the entry to the export.

Thus, during operation of the power transmission device, the first shaft and the second shaft rotate together, and after the lubricating grease passes through the first oil reservoir space from the second oil reservoir space through the inter-coupled male and female spline sections in the inner bore of the first shaft, the lubricating grease will enter the inlet of the flow passage in the first oil reservoir space under the action of centrifugal force, and because the flow passage is provided to extend away from the central axis from the inlet to the outlet, the lubricating grease entering the flow passage will flow toward the outlet of the flow passage under the urging of centrifugal force, and eventually return to the second oil reservoir space, without leaking out from the first oil reservoir space via the tip end of the first shaft, whereby effective sealing of the lubricating grease is ensured very effectively with a simple configuration.

The power transmission device proposed by the present invention may comprise one or more of the following further developments.

According to one or some embodiments, the inlet of the flow channel is arranged close to a radial bottom of the annular groove. Thereby, it can be ensured that the lubricating grease introduced into the first oil storage space can be timely and almost completely or completely returned into the second oil storage space via the flow passage.

According to one or some embodiments, a distance from the inlet of the flow passage to the central axis is smaller than a radius of an inner oil surface of an annular oil ring formed by the grease in the second oil reservoir space when the first shaft and the second shaft rotate. That is, during operation of the power transmission device, the first shaft and the second shaft rotate together, and the lubricating grease present in the second oil reservoir will form an annular oil ring, for example, against the radial bottom wall of the second oil reservoir due to the centrifugal force. At this time, in order to ensure that the lubricating grease flowing into the first oil storage space can smoothly return to the second oil storage space by the centrifugal force, the distance from the inlet of the flow passage to the central axis may be set smaller than the radius of the inner oil surface of the annular oil ring formed in the second oil storage space. In this way, the hydraulic pressure applied by the annular oil ring formed in the second oil reservoir space at the outlet of the flow passage provided in the second oil reservoir space will be lower than the centrifugal force to which the lubricating grease entering the flow passage via the inlet of the flow passage and returning from the outlet of the flow passage to the second oil reservoir space is subjected at the outlet of the flow passage, whereby the lubricating grease will smoothly return to the second oil reservoir space.

According to one or some embodiments, the number of flow channels is 2 to 4.

According to one or some embodiments, the flow passages are regularly distributed around the central axis. Thereby, it is possible to ensure a more rapid and efficient return to the second oil storage space when flowing into the first oil storage space.

According to one or some embodiments, the flow passage is a bore in the first shaft. Thereby, the flow channel can be realized in a compact and simple manner without using additional components.

According to one or some embodiments, the flow passage is a cutout at a root of an internal spline in the internally splined section. This also makes it possible to realize the flow channel in a compact and simple manner without using additional parts and is advantageous in ensuring the strength of the first shaft.

According to one or some embodiments, the first shaft forms a clearance fit with the second shaft near the end. This is because according to the utility model discloses, owing to set up the runner as above injectd, the lubricating grease who gets into first oil storage space can effectively return to second oil storage space, and can not leak away from the end of primary shaft.

According to one or some embodiments, the first shaft is provided with a sealing ring between the vicinity of the end and the second shaft. This may further ensure a good seal.

According to another aspect of the present invention, an electric drive assembly system is provided, including the power transmission device as described above.

In accordance with one or some embodiments, the electric drive assembly system further comprises a motor and a gearbox, wherein the first shaft is a motor shaft and the second shaft is a gearbox input shaft.

According to yet another aspect of the present invention, a vehicle is provided, comprising an electric drive assembly system as described above.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present disclosure and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings may be obtained from the drawings without inventive effort. In the drawings:

fig. 1 shows a cross-sectional view of a power transmission device according to an embodiment of the present invention, in which a first oil storage space, a second oil storage space, and a flow passage are shown;

fig. 2 shows a cross-sectional view of a power transmission device in an operating state according to an embodiment of the present invention;

fig. 3 shows a cross-sectional view of a power transmission device in a non-operating state according to an embodiment of the present invention.

List of reference numerals

10 power transmission device

100 first shaft

110 first end section

111 annular groove

1101 radial bottom of the annular groove

Radial wall of annular 1102 groove

120 second end section

1201 radial bottom wall of the second oil storage space

130 internally splined section

140 flow passage

141 runner inlet

142 outlet of the flow passage

150 ring oil ring

151 inner oil level

160 end of the first shaft

170 axial bottom wall of the inner bore

200 second shaft

230 externally splined section

270 end face of the second shaft

Central axis of X

radius of inner oil surface of r-ring oil ring

Detailed Description

Hereinafter, a power transmission device according to an embodiment of the present disclosure is described in detail with reference to the drawings. To make the objects, technical solutions and advantages of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are some, but not all embodiments of the present disclosure.

Thus, the following detailed description of the embodiments of the present disclosure, presented in conjunction with the figures, is not intended to limit the scope of the claimed disclosure, but is merely representative of selected embodiments of the disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

The singular forms include the plural unless the context otherwise dictates otherwise. Throughout the specification, the terms "comprises," "comprising," "has," "having," "includes," "including," "having," "including," and the like are used herein to specify the presence of stated features, integers, steps, operations, elements, components, or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof.

In addition, even though terms including ordinal numbers such as "first", "second", etc., may be used to describe various elements, the elements are not limited by the terms, and the terms are used only to distinguish one element from another. For example, a first component could be termed a second component, and, similarly, a second component could be termed a first component, without departing from the scope of the present disclosure.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, or orientations or positional relationships that are conventionally placed when the disclosed products are used, or orientations or positional relationships that are conventionally understood by those skilled in the art, and are used merely for convenience of describing and simplifying the present disclosure, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present disclosure.

As shown in fig. 1, according to an aspect of the present invention, there is provided a power transmission device 10, the power transmission device 10 including at least a first shaft 100 and a second shaft 200 spline-coupled to each other to rotate together. The first and second shafts 100, 200 may both extend along a central axis X as shown, and a bore extending along said central axis X is provided in the first shaft 100, a first axial end of which opens into the end 160 of the first shaft 100 and thus the end 160 of the first shaft 100 is an open end, and an internally splined section 130 may be provided in the bore. More specifically, the bore may include an internally splined section 130 and first and second end sections 110, 120 disposed on axially opposite sides of the internally splined section 130, the first end section 120 being disposed proximate the distal end 160 of the first shaft 100, the second end section 120 being disposed proximate a second axial end of the bore opposite the first axial end. On the second shaft 200 is provided an externally splined section 230 corresponding to the internally splined section 130 in the bore of the first shaft 100. Thus, the second shaft 200 may be inserted into the bore of the first shaft 100 via the open end 160 of the first shaft 100 such that the externally splined section 230 of the second shaft 200 and the internally splined section 130 in the bore of the first shaft 100 are coupled to one another such that the first and second shafts 100, 200 may rotate together to transfer power therebetween. It is known that lubricating grease needs to be applied to the inner spline section 130 and the outer spline section 230 to ensure that the splines do not rust, so that the first shaft 100 and the second shaft 200 can function well and reduce noise.

In a particular case, the second end section 120 of the inner bore of the first shaft 200 may form an oil reservoir space, hereinafter referred to as second oil reservoir space, in which a lubricating grease for lubricating the inner and outer splines may be at least partially present. And more specifically, the inner bore of the first shaft 100 may be blind or blind at the second axial end, i.e. the inner bore has an axial bottom wall 170 made of the material of the first shaft 100, such that, in axial direction, a second oil reservoir space may be defined between the axial bottom wall 170 of the inner bore and the end face 270 of the second shaft 200. The lubricating grease may be at least partially distributed to the internally splined section 130 and the externally splined section 230 at least in the operational state of the power transmission device 10, i.e. when the first shaft 100 and the second shaft 200 are rotating, and in order to prevent the lubricating grease from leaking out of the open end 160 of the first shaft 100, it is necessary to provide a means for sealing the lubricating grease at or near the end 160 of the first shaft 100.

To this end, the present invention proposes that, as shown in fig. 1, an annular groove 111 is provided on an inner wall of the first end section 110 of the inner bore of the first shaft 100, the annular groove 111 extends circumferentially so that an oil storage space, hereinafter referred to as a first oil storage space, may be formed between the annular groove 111 and the second shaft 200, and one or more flow passages 140 are provided between the first oil storage space and the second oil storage space, an inlet 141 of the flow passage 140 is provided in the first oil storage space, an outlet 142 of the flow passage 140 is provided in the second oil storage space, and the flow passage 140 is provided to extend from the inlet 141 to the outlet 142 thereof away from the central axis X. Such a flow passage may be provided as a straight flow passage as shown in the drawings, or may be provided as a curved flow passage not shown as long as it extends away from the central axis X from the inlet to the outlet. More specifically, the number of the flow passages 140 may be 2 to 4, and the flow passages 140 thereof may be regularly distributed, for example, uniformly distributed, around the central axis X.

Thus, during operation of the power transmission device 10, the first shaft 100 and the second shaft 200 rotate together, and after the lubricating grease flows in the inner bore of the first shaft 100 from the second oil reservoir space to the first oil reservoir space through the inter-coupled male spline section 130 and the female spline section 230, the lubricating grease will enter the inlet 141 of the flow passage 140 in the first oil reservoir space under the influence of centrifugal force, and because the flow passage 140 is provided to extend away from the central axis X from the inlet 141 to the outlet 142, the lubricating grease entering the flow passage 140 will flow toward the outlet 142 of the flow passage 140, and eventually return to the second oil reservoir space, urged by centrifugal force, without leaking out from the first oil reservoir space via the distal end 160 of the first shaft 100, thereby very effectively ensuring effective sealing of the lubricating grease with a simple configuration. In addition, this may allow a clearance fit to be formed between the first shaft 100 near the open end 160 and the second shaft 200, since according to the present invention, the grease entering the first oil storage space can be effectively returned to the second oil storage space without leaking out from the end 160 of the first shaft 100 due to the provision of the flow passage 140 defined as above.

Of course, additionally, according to embodiments not shown in the figures, a sealing ring may also be provided between the vicinity of the open end 160 of the first shaft 100 and the second shaft 200. This further ensures a good seal.

According to one or some embodiments, as shown in FIG. 1, the inlet 141 of the flow channel 140 may be disposed proximate a radial bottom 1101 of the annular groove 111. More specifically, the inlet 141 of the flow channel 140 may be disposed in a radial wall 1102 that connects with a radial bottom 1101 of the annular groove 111, and is disposed immediately adjacent to the radial bottom 1101 of the annular groove 111. Thereby, it can be ensured that the lubricating grease introduced into the first oil storage space can be timely and almost completely or completely returned into the second oil storage space via the flow passage 140. Further, to facilitate a more compact configuration, the outlet 142 of the flow passage 140 may be disposed close to the radial bottom wall 1201 of the second oil storage space, which may maximize the slope of the flow passage 140 from the flow passage inlet 141 to the flow passage outlet 142 with respect to the central axis X, so that the grease in the flow passage 140 may flow back into the second oil storage space more quickly and efficiently due to the increased centrifugal force.

According to one or some embodiments, in an operating state of the power transmission device 10, that is, when the first shaft 100 and the second shaft 200 rotate, the distance from the inlet 141 of the flow passage 140 to the central axis X is smaller than the radius r (shown in fig. 2) of the inner oil surface 151 of the annular oil ring 150 formed by the lubricating grease in the second oil reservoir space. That is, during operation of the power transmission device 10, the first shaft 100 and the second shaft 200 rotate together, and the lubricating grease present in the second oil reservoir will form an annular oil ring, for example, against the radial bottom wall 1201 of the second oil reservoir due to the centrifugal force. At this time, in order to ensure that the lubricating grease flowing into the first oil storage space can smoothly return to the second oil storage space by the centrifugal force, a distance from the inlet 141 of the flow passage 140 to the central axis X may be set smaller than the radius r of the inner oil surface 151 of the annular oil ring 150 formed in the second oil storage space. In this way, the hydraulic pressure applied by the annular oil ring 150 formed in the second oil storage space at the outlet 142 of the flow passage 140 provided in the second oil storage space will be lower than the centrifugal force to which the lubricating grease entering the flow passage 140 via the inlet 141 of the flow passage 140 and returning from the outlet 142 of the flow passage 140 to the second oil storage space is subjected at the outlet 142 of the flow passage 140, whereby the lubricating grease will smoothly return to the second oil storage space.

It should be noted that during normal operation, the centrifugal force to which the grease is subjected when the first and second shafts 100, 200 rotate will be much greater than gravity, for example, if the first and second shafts 100, 200 rotate at a speed of 12000rmp, in a specific embodiment, the centripetal acceleration of the grease will be greater than 30000m/s at a radial distance of 40mm from the central axis X²This means that the centrifugal forces to which it is subjected will be up to 3000N. Therefore, according to the present invention, the lubricating grease entering the first oil storage space can be returned to the second oil storage space via the flow passage 140 under the action of the centrifugal force.

Further, it should be noted that in the non-operating state of the power transmission device 10 as shown in fig. 3, i.e., when the first shaft 100 and the second shaft 200 are held stationary, most of the lubricating grease O will exist in the second oil storage space, and the amount of the lubricating grease O is designed not to leak out via the internally splined section 130 and the externally splined section 230.

According to one or some embodiments, as shown in FIG. 1, the flow channel 140 is a bore in the first shaft 100. Thereby, the flow channel can be realized in a compact and simple manner without using additional components. It should be noted that in this case the drilling tool will extend from the open end 160 of the first shaft 100 into the annular groove 111 at the first end section 110 of the bore and travel from the flow passage inlet 141 located in the annular groove 111 to the flow passage outlet 142 located in the second oil storage space. Accordingly, the open end 160 of the first shaft 100 and the annular groove 111 should be designed so as not to interfere with the insertion and drilling operations of the drilling tool.

According to an embodiment not shown, the flow channel 140 may be a recess at the root of the internal spline in the internally splined section 130, which also allows a compact and simple way of achieving a flow channel without using additional parts and which is advantageous for ensuring the strength of the first shaft.

According to another aspect of the present invention (not shown), an electric drive assembly system is provided that includes a power transmission device 10 according to the present invention. More specifically, the electric drive assembly system may further comprise a motor and a gearbox, wherein the first shaft 100 is a motor shaft and the second shaft 200 is a gearbox input shaft. Such an electric drive assembly system can be used, for example, in a vehicle.

The exemplary embodiment of the power transmission device proposed by the present invention has been described in detail with reference to the preferred embodiments, however, it will be understood by those skilled in the art that various modifications and improvements can be made to the above specific embodiments without departing from the concept of the present invention, and various combinations of the various technical features and structures proposed by the present invention can be made without departing from the scope of the present invention.

The scope of the present disclosure is not defined by the above-described embodiments but is defined by the appended claims and equivalents thereof.

Claims (12)

1. A power transmission device, characterized in that the power transmission device (10) includes:

a first shaft (100) extending along a central axis (X), the first shaft (100) being provided with a bore extending along the central axis (X), the bore comprising a first end section (110), a second end section (120) and an internally splined section (130) between the first end section (110) and the second end section (120), the first end section (110) being provided proximate to a tip (160) of the first shaft (100);

a second shaft (200) extending along the central axis (X) and comprising an externally splined section (230) corresponding to the internally splined section (130),

wherein an annular groove (111) is arranged on the inner wall of the first end section (110), a first oil storage space is formed between the annular groove (111) and the second shaft (200), and a second oil storage space is formed by the second end section (120),

a flow passage (140) is provided between the first oil storage space and the second oil storage space, the flow passage (140) extending from an inlet (141) in the first oil storage space to an outlet (142) in the second oil storage space away from the central axis (X).

2. The power transmission device of claim 1, wherein the inlet (141) of the flow channel (140) is disposed proximate a radial bottom (1101) of the annular groove (111).

3. The power transmission device according to claim 2, characterized in that a distance from the inlet (141) of the flow passage (140) to the center axis (X) is smaller than a radius of an inner oil surface (151) of an annular oil ring (150) formed by the lubricating grease in the second oil reservoir space when the first shaft (100) and the second shaft (200) rotate.

4. The power transmission device according to any one of claims 1 to 3, characterized in that the number of the flow passages (140) is 2 to 4.

5. The power transmission device as claimed in claim 4, characterized in that the flow passages (140) are regularly distributed around the central axis (X).

6. The power transmission device according to any one of claims 1 to 3, characterized in that the flow passage (140) is a bore hole in the first shaft (100).

7. The power transmission device as claimed in any one of claims 1 to 3, wherein the flow channel (140) is a cutout at a root of an internal spline in the internally splined section (130).

8. The power transmission device of any of claims 1-3, wherein the first shaft (100) forms a clearance fit with the second shaft (200) near the tip (160).

9. The power transmission device according to any one of claims 1 to 3, characterized in that the first shaft (100) is provided with a seal ring between the vicinity of the tip end (160) and the second shaft (200).

10. An electric drive assembly system, characterized in that it comprises a power transmission device (10) according to any one of claims 1 to 9.

11. The electric drive assembly system of claim 10, further comprising a motor and a gearbox, wherein the first shaft (100) is a motor shaft and the second shaft (200) is a gearbox input shaft.

12. A vehicle characterized in that it comprises an electric drive assembly system according to claim 10 or 11.

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