AU2018455574B2

AU2018455574B2 - Drum gear

Info

Publication number: AU2018455574B2
Application number: AU2018455574A
Authority: AU
Inventors: Chengpan WU; Guoqing Wu; Xunlin ZHANG; Yongqiang ZHAO
Original assignee: CRRC Qishuyan Institute Co Ltd
Current assignee: CRRC Qishuyan Institute Co Ltd
Priority date: 2018-12-28
Filing date: 2018-12-28
Publication date: 2022-11-24
Anticipated expiration: 2038-12-28
Also published as: AU2018455574A1; WO2020133264A1

Abstract

A drum gear comprises a sleeve (21), an extension portion (22), and a drum tooth portion (23). The extension potion extends from an end of the sleeve to another end of the sleeve, and an annular gap (24) having an opening is formed between the extension portion and the sleeve. The drum tooth portion is disposed at a peripheral surface of the extension portion, and is engaged with an inner tooth portion in a drum coupling. An arc-shaped surface (211) is provided at a peripheral surface of the sleeve, and is engaged with an annular seal portion in the drum coupling. The gear is used to resolve the issue in the prior art in which drum gear couplings wear and vibrate easily during operation.

Description

Drum Gear

Technical Field The present invention relates to the technical field of coupling, and in particular, to a drum gear. Background The coupling is mainly used to connect two shafts (the driving shaft and the driven shaft) in different mechanisms and makes them rotate together to complete the task of torque transmission, and is widely used in mechanical transmission equipment. In the field of rail transport, Gear coupling is a key component for the bogie of a rail vehicle, and plays an important role in transmitting traction load and compensating for a displacement deviation between an output shaft of an electric motor and a high-speed shaft of a gearbox. In high-speed and heavy-load power transmission of rail transport, a coupling must also have the effects of buffering, damping and improving dynamic performances. There are many types of couplings. Generally, according to the relative positions and changes in the positions of the two shafts connected, the couplings can be categorized into and movable couplings. Fixed couplings are used primarily where strict centering of the two shafts is required and no relative displacement occurs during operation. Movable couplings are primarily used where there is a deflection between two shafts or there is a relative displacement during operation. According to the method of compensating a displacement, the movable couplings are divided into rigid movable couplings and elastic movable couplings. Curved tooth couplings belong to rigid movable couplings, and are widely used in various mechanical transmission systems such as rail transit, ships and mines due to relatively large capability for compensation of axial and radial displacements and angular displacement. The curved tooth coupling is mainly composed of a sleeve with internal teeth and a drum gear with external teeth, the internal teeth and the external teeth meshing with each other. Since the external teeth of the drum gear are drum-shaped, an angular displacement and an axial displacement are allowed between the sleeve and the drum gear, thus allowing a relative displacement of the drive shaft and the driven shaft, which are connected by means of the curved tooth coupling, in the rotary

1 PN145302QSHY movement. Generally, one side of the curved tooth coupling is connected to an output shaft (a driving shaft) of the electric motor, and the other side of the curved tooth coupling is connected to an input shaft (a driven shaft) of the gear transmission box. Since the two shafts connected to the curved tooth coupling will have a relative displacement during operation, the tooth faces of the inner and external teeth periodically slide relative to each other in the axial direction, which necessarily results in tooth face wear and power loss. To reduce the wear of the teeth and the frictional resistance to relative movement, the coupling needs to operate in good lubrication and sealing conditions. Patent CN 1181469 A discloses a coupling gear capable of maintaining the satisfactory seal even when the two axes are displaced and prolonging the service life of the seal element. The patent mainly uses a spring provided on the drum gear shaft body to push an adapted surface of an end cover and a seal element which is slidably provided on an outer peripheral surface of drum gear main body and has a spherical sealing surface, thereby enhancing the sealing performance of the coupling, reducing wear of the seal element, and prolonging the service life of the seal element. Patent CN 1101899 C discloses a coupling which can avoid the exchange of media and wear of the sealing elements during operation. In the solution, between the coupling sleeve and each coupling component, it is provided at least one axial corrugated pipe secured to at least one of both parts, and the corrugated pipe seals the synchronous gear pair and also resiliently adjusts the position of the coupling sleeve. A drum gear, as one of the primary structures in a curved tooth coupling, has a direct impact on the performance of the curved tooth coupling. In the patents above or other related art, when the drum gear of the curved tooth coupling is deflected relative to the housing, the seal between the seal element and the drum gear is not tight, and different parts of the seal element are unevenly worn, which greatly affects the sealing effect and service life of the coupling.

Summary Some embodiments of the present invention provides a drum gear, so as to solve the problem in the related art that a curved tooth coupling has a poor sealing

2 PN145302QSHY performance. In order to solve the problem, an embodiment of the present invention provides a drum gear, including: a sleeve body, an extension portion and a drum tooth portion, wherein the extension portion extends from one end of the sleeve body to the other end of the sleeve body, an annular gap having an opening is formed between the extension portion and the sleeve body, the drum tooth portion is provided on an outer peripheral surface of the extension portion, and is engaged with an internal tooth portion of a curved tooth coupling, and an arc-shaped surface is provided on an outer peripheral surface of the sleeve body, and is engaged with an annular seal portion of the curved tooth coupling. In one embodiment, a plane perpendicular to an axial direction of the drum tooth portion and passing through a midpoint of a width of the drum tooth portion is a central plane, and a highest point of the arc-shaped surface is located on the central plane. In one embodiment, the arc-shaped surface is a spherical surface. In one embodiment, a surface, where a tooth tip of the drum tooth portion is located, is a second spherical surface, and a spherical center of the arc-shaped surface coincides with a spherical center of the second spherical surface. In one embodiment, the sleeve body includes a first sleeve section and a second sleeve section which are sequentially connected, the extension portion is provided on the first sleeve section in a surrounding manner and extends towards the second sleeve section, and the arc-shaped surface is located on an outer peripheral surface of the second sleeve section. In one embodiment, an outer peripheral surface of the second sleeve section is a spherical surface, or an outer peripheral surface of the second sleeve section consists of a spherical surface and a cylindrical surface. In one embodiment, the extension portion includes a connection section and an extension section, wherein two ends of the connection section are respectively connected to the first sleeve section and the extension section, the annular gap is located between the extension section and the arc-shaped surface, and the drum tooth portion is located on an outer peripheral surface of the extension section. In one embodiment, a spherical surface is provided on one side of the extension portion away from the annular gap, a spherical center of the spherical surface coincides with the spherical center of the second spherical surface, and the spherical

3 PN145302QSHY surface is configured for coupling with a limiting spherical surface of the curved tooth coupling. In one embodiment, the extension portion includes a connection section and an extension section, two ends of the connection section are respectively connected to the sleeve body and the extension section, the annular gap is located between the extension section and the sleeve body, the drum tooth portion is located on an outer peripheral surface of the extension section, the spherical surface is provided at a joint of the connection section and the extension section, and the spherical surface is located on one side of the joint away from the annular gap. In one embodiment, the extension portion includes a connection section and an extension section, two ends of the connection section are respectively connected to the sleeve body and the extension section, the annular gap is located between the extension section and the sleeve body, the drum tooth portion is located on an outer peripheral surface of the extension section, and the spherical surface is located on one side of the connection section away from the annular gap. In one embodiment, the extension portion includes a connection section and an extension section, two ends of the connection section are respectively connected to the sleeve body and the extension section, the annular gap is located between the extension section and the sleeve body, the drum tooth portion is located on an outer peripheral surface of the extension section, the extension portion further has a through hole, the through hole is configured for connecting cavities on two sides of the extension portion, and the through hole is provided on the connection section or the extension section. In one embodiment, an inner wall of the sleeve body is provided with an oil guide groove. In one embodiment, the oil guide groove is spirally wound on an inner wall of the sleeve body. In one embodiment, the sleeve body, the extension and the drum tooth portion are of an integrated structure. By applying the technical solution of the present invention, a drum tooth portion is provided on an extending portion of a drum gear, and in this way, the drum gear can be made to swing and axially move by means of the engagement between the drum tooth portion and an internal tooth portion of a curved tooth coupling. Since an outer peripheral surface of the sleeve body of the drum gear is provided with an

4 PN145302QSHY arc-shaped surface, when the drum gear deflects, the circumference of the annular seal portion uniformly contacts the arc-shaped surface of the sleeve body to perform sealing. In this way, on the one hand, a better sealing effect of the drum gear at different positions can be ensured, and on the other hand, the annular seal portion is evenly worn, so that the sealing effect of the curved tooth coupling during operation and the service life can be improved.

Brief Description of the Drawings The drawings, which constitute a part of the description, are intended to provide better understanding of the present invention, and the exemplary embodiments of the present invention and their description aim to only illustrate the present invention but not to limit the present invention. In the drawings: FIG. 1 shows a schematic structural view of a drum gear provided in embodiment I of the present invention; FIG. 2 shows a schematic structural view of a drum gear provided in embodiment II of the present invention; FIG. 3 shows a schematic view of the application of the drum gear in FIG. 1 to a curved tooth coupling; FIG. 4 shows a schematic view of the application of the drum gear in FIG. 2 to a curved tooth coupling. The drawings include the following reference signs: 10, sleeve; 12, internal tooth portion; 21, sleeve body; 211, arc-shaped surface; 212, first sleeve section; 213, second sleeve section; 214, oil guide groove; 22, extension portion; 221, spherical surface; 222, connection section; 223, extension section; 23, drum tooth portion; 24, annular gap;25. through hole; 50, annular seal portion.

Detailed Description of the Embodiments The technical solutions of the embodiments of the present disclosure will be described in a clearly and fully understandable way in connection with the drawings related to embodiments of the present invention. Obviously, the embodiments as described are only parts of embodiments rather than all the possible embodiments thereof. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or

5 PN145302QSHY uses. All embodiments obtained by an ordinary person skilled in the art without involving inventive work based on the embodiments of the present invention fall into the scope of protection of the present invention. As shown in FIG. 1, embodiment i of the present invention provides a drum gear, including: a sleeve body 21, an extension portion 22 and a drum tooth portion 23, wherein the extension portion 22 extends from one end of the sleeve body 21 to the other end of the sleeve body 21, an annular gap 24 having an opening is formed between the extension portion 22 and the sleeve body 21, the drum tooth portion 23 is provided on an outer peripheral surface of the extension portion 22, and is engaged with an internal tooth portion of a curved tooth coupling, and an arc-shaped surface 211 is provided on an outer peripheral surface of the sleeve body 21, and is engaged with an annular seal portion of the curved tooth coupling. By applying the technical solution of the present invention, a drum tooth portion 23 is provided on an extending portion 22 of a drum gear, and in this way, the drum gear can be made to swing and axially move by means of the engagement between the drum tooth portion 23 and an internal tooth portion of a curved tooth coupling. Since an outer peripheral surface of the sleeve body 21 of the drum gear is provided with an arc-shaped surface 211, when the drum gear deflects, the circumference of the annular seal portion uniformly contacts the arc-shaped surface 211 of the sleeve body 21 to perform sealing. In this way, on the one hand, a better sealing effect of the drum gear at different positions can be ensured, and on the other hand, the annular seal portion 50 wears evenly at different parts, so that the sealing effect of the curved tooth coupling during operation and the service life can be effectively improved. In the present embodiment, the drum tooth portion 23 consists of a plurality of drum teeth. In the present embodiment, a plane perpendicular to an axial direction of the drum tooth portion 23 and passing through a midpoint of a width of the drum tooth portion 23 is a central plane, and a highest point of the arc-shaped surface 211 is located on the central plane. In an initial state, one end of the annular seal portion is in contact with the circumference where the highest point of the arc-shaped surface 211 is located, so that when the drum gear deflects relative to the sleeve 10 of the curved tooth coupling, the circumference of the annular seal portion is always in contact with the arc-shaped surface 211 of the sleeve body 21, the elastic deformation amount is relatively less, and the sealing effect is better. In the present embodiment, the arc surface 211 may be set as a spherical

6 PN145302QSHY surface. Thus, when the sleeve body 21 rotates, even if the position of the arc-shaped surface 211 in contact with the annular seal portion changes, the elastic deformation amount of the annular seal portion 50 does not change in the absence of axial displacement of the sleeve body 21; when there is an axial displacement of the sleeve body 21, only a small uniform deformation occurs at different positions of the annular seal portion 50 in contact with the spherical surface. Therefore, by means of the technical solution, good sealing can be achieved at different contact positions of the arc-shaped surface 211 and the annular seal portion 50, and the annular seal portion 50 wears evenly at different contact parts, so that the sealing effect of the curved tooth coupling during operation and the service life can be effectively improved. In the present embodiment, the spherical surface is not a complete spherical surface, and may be understood as an annular partial spherical surface. In the present embodiment, a surface, where a tooth tip of the drum tooth portion 23 is located, is a second spherical surface, and a spherical center of the arc-shaped surface 211 coincides with a spherical center of the second spherical surface. By means of the described arrangement, when the drum gear deflects relative to the sleeve 10, no additional torque is generated, and therefore wearing or vibration of the sleeve 10 and the drum gear can be reduced, thereby further prolonging the service life of the curved tooth coupling. In the present embodiment, the sleeve body 21 includes a first sleeve section 212 and a second sleeve section 213 which are sequentially connected, the extension portion 22 is provided on the first sleeve section 212 in a surrounding manner and extends towards the second sleeve section 213, and the arc-shaped surface 211 is located on an outer peripheral surface of the second sleeve section 213. Specifically, an outer peripheral surface of the second sleeve section 213 is a spherical surface, or the peripheral surface of the second sleeve section 213 consists of a spherical surface and a cylindrical surface. Provided as above, the reasonable arrangement of a geometrical structure shape and the reasonable arrangements of the overall geometrical structures and shapes of the drum tooth portion 23 and the curved tooth coupling are facilitated, the structure is compact, and it can be ensured that the drum gear has sufficient strength and is easy to process and detect. In the present embodiment, the extension portion 22 includes a connection section 222 and an extension section 223, wherein two ends of the connection section 222 are respectively connected to the first sleeve section 212 and the

7 PN145302QSHY extension section 223, the annular gap 24 is located between the extension section 223 and the arc-shaped surface 211, and the drum tooth portion 23 is located on an outer peripheral surface of the extension section 223. This facilitates the formation of the annular gap 24 and the arrangement of the drum tooth portion 23. In the present embodiment, a spherical surface 221 is provided on one side of the extension portion 22 away from the annular gap 24, a spherical center of the spherical surface 221 coincides with the spherical center of the second spherical surface, and the spherical surface 221 is configured for coupling with a limiting spherical surface of the curved tooth coupling. Provided as above, when limiting, two spherical surfaces are configured for cooperation, without affecting the engagement between the drum tooth portion 23 and the internal tooth portion 12 in the sleeve 10, the contact area of the limiting area is increased, the force applied per unit area is reduced, and no additional torque is generated, thereby avoiding aggravating wearing or vibration of the sleeve 10 and the drum gear when limiting, and improving the stability of the curved tooth coupling during operation and the service life. Specifically, in the present embodiment, the extension portion 22 includes a connection section 222 and an extension section 223, two ends of the connection section 222 are respectively connected to the sleeve body 21 and the extension section 223; the annular gap 24 is located between the extension section 223 and the sleeve body 21; the drum tooth portion 23 is located on an outer peripheral surface of the extension section 223, the spherical surface 221 is provided at a joint of the connection section 222 and the extension section 223, and the spherical surface 221 is located on one side of the joint away from the annular gap 24. This facilitates the contact between the extension portion 22 and other components, so as to limit the extension portion 22. In the present embodiment, the extension portion 22 includes a connection section 222 and an extension section 223; two ends of the connection section 222 are respectively connected to the sleeve body 21 and the extension section 223; the annular gap 24 is located between the extension section 223 and the sleeve body 21; the drum tooth portion 23 is located on an outer peripheral surface of the extension section 223; the extension portion 22 further has a through hole 25; the through hole is configured for connecting cavities on two sides of the extension portion 22; and the through hole 25 is provided on the connection section 222 or the extension section 223. If the cavities on both sides of the extension portion 22 are respectively

8 PN145302QSHY sealed, when the extension portion 22 moves, the pressure inside the cavities will change greatly, causing an unstable operation of the curved tooth coupling. After the cavities on two sides of the extension portion 22 are communicated by means of the through hole 25, pressures in different cavities can be balanced, thereby avoiding an unstable operation brought to the curved tooth coupling. Furthermore, the lubricating media in the cavities on both sides of the extension portion 22 can also flow through the through hole 25, so that the lubricating media is distributed more evenly, thereby improving the lubrication effect. In the present embodiment, an inner wall of the sleeve body 21 is provided with an oil guide groove 214. In this way, when assembling and disassembling the motor shaft or other shaft components accommodated in the sleeve body 21, pressure oil can be input into the oil guide groove 214 to reduce friction. Specifically, the oil guide groove 214 is spirally wound on an inner wall of the sleeve body 21. In this way, the area of the oil film on an inner wall of the sleeve body 21 can be increased, and the friction between components such as a shaft and the sleeve body 21 can be further reduced. In the present embodiment, the sleeve body 21, the extension portion 22 and the drum tooth portion 23 are of an integrated structure. It is preferably integrally formed by forging, i. e. first manufacturing a forging blank of the drum gear, and then machining the drum tooth portion 23 to obtain the drum gear. Other manufacturing processes may also be used. This can increase the structural strength of the drum gear. Of course, the drum gear can also be provided as a split structure according to needs. As shown in FIG. 2, in embodiment II of the present invention, different from embodiment I, the extension portion 22 includes a connection section 222 and an extension section 223; two ends of the connection section 222 are respectively connected to the sleeve body 21 and the extension section 223; the annular gap 24 is located between the extension section 223 and the sleeve body 21; the drum tooth portion 23 is located on an outer peripheral surface of the extension section 223; and the spherical surface 221 is located on one side of the connection section 222 away from the annular gap 24. This facilitates the contact between the extension portion 22 and other components, so as to limit the extension portion 22. Also, the drum gear can be made to have a high strength. By applying the technical solution of the present invention, the drum tooth

9 PN145302QSHY portion 23 is provided on the extending portion 22 of the drum gear, and in this way, the drum gear can be made to swing and axially move by means of the engagement between the drum tooth portion 23 and the internal tooth portion of the curved tooth coupling. Since the outer peripheral surface of the sleeve body 21 of the drum gear is provided with the arc-shaped surface 211, when the drum gear deflects, the circumference of the annular seal portion uniformly contacts the arc-shaped surface 211 of the sleeve body 21 to perform sealing. In this way, on the one hand, a better sealing effect of the drum gear at different positions can be ensured, and on the other hand, the annular seal portion 50 wears evenly, so that the sealing effect of the curved tooth coupling during operation and the service life can be improved. The preferred embodiments of the present invention described above are intended to illustrate but not limit the present invention. To those skilled in the art, various modifications and variations may be available for the present invention. Any modification, equivalent substitution, and improvement within the spirit and principle of the present invention should be covered in the scope of protection of the present invention.

10 PN145302QSHY

Claims

What is claimed is: 1. A drum gear, comprising: a sleeve body, an extension portion, and a drum tooth portion, wherein the extension portion extends from one end of the sleeve body to the other end of the sleeve body, an annular gap has an opening being formed between the extension portion and the sleeve body, the drum tooth portion is provided at an outer peripheral surface of the extension portion, and is engaged with an internal tooth portion of a curved tooth coupling; and an arc-shaped surface is provided at an outer peripheral surface of the sleeve body, and is engaged with an annular seal portion of the curved tooth coupling, the arc-shaped surface is a spherical-shaped surface, a surface, where a tooth tip of the drum tooth portion is located, is a second spherical surface, and a spherical center of the arc-shaped surface coincides with a spherical center of the second spherical surface, a spherical surface is provided on one side of the extension portion away from the annular gap, a spherical center of the spherical surface coincides with the spherical center of the second spherical surface, and the spherical surface is configured for coupling with a limiting spherical surface of the curved tooth coupling, the extension portion comprises a connection section and an extension section, two ends of the connection section are respectively connected to the sleeve body and the extension section, the annular gap is located between the extension section and the sleeve body, the drum tooth portion is located on an outer peripheral surface of the extension section, wherein the spherical surface is provided at a joint of the connection section and the extension section, and the spherical surface is located on one side of the joint away from the annular gap; or the spherical surface is located on one side of the connection section away from the annular gap.
2. The drum gear as claimed in claim 1, wherein a plane perpendicular to an axial direction of the drum tooth portion and passing through a midpoint of a width of the drum tooth portion is a central plane, and a highest point of the arc-shaped surface is located on the central plane.
3. The drum gear as claimed in claim 1, wherein the sleeve body comprises a first sleeve section and a second sleeve section which are sequentially connected, the extension portion is provided on the first sleeve section in a surrounding manner and extends towards the second sleeve section, and the arc-shaped surface is located on an outer peripheral surface of the second sleeve section.
4. The drum gear as claimed in claim 3, wherein an outer peripheral surface of the second sleeve section is a spherical surface, or an outer peripheral surface of the second sleeve section consists of a spherical surface and a cylindrical surface.
5. The drum gear as claimed in claim 3, wherein the extension portion comprises a connection section and an extension section, wherein two ends of the connection section are respectively connected to the first sleeve section and the extension section, the annular gap is located between the extension section and the arc-shaped surface, and the drum tooth portion is located on an outer peripheral surface of the extension section.
6. The drum gear as claimed in claim 1, wherein the extension portion further has a through hole, the through hole is configured for connecting cavities on two sides of the extension portion, and the through hole is provided on the connection section or the extension section.
7. The drum gear as claimed in claim 1, wherein an oil guide groove is provided on an inner wall of the sleeve body.
8. The drum gear as claimed in claim 7, wherein the oil guide groove is spirally wound on the inner wall of the sleeve body.
9. The drum gear as claimed in claim 1, wherein the sleeve body, the extension and the drum tooth portion are of an integrated structure.

Fig. 1

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Fig. 2

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Fig. 3

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Fig. 4

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