A SEALING ARRANGEMENT FOR A HYDRODYNAMIC MACHINE FOR A VEHICLE

Abstract

A sealing arrangement (1) for a hydrodynamic machine (3) is configured to seal a space (5) between a shaft (7) and a housing (9) of the hydrodynamic machine (3). The sealing arrangement (1) includes a sealing housing (11), a first sealing ring (13), and a second sealing ring (15). The first sealing ring (13) is connected to the shaft (7) and the second sealing ring (15) is arranged in the sealing housing (11). The second sealing ring (15) is configured to sealingly abut against the first sealing ring (13) in a first abutment interface (17). The sealing housing (11) includes a wall (21) protruding into a coolant space (19) adjacent to the first abutment interface (17) for directing a flow of coolant in the coolant space (19). Further, a hydrodynamic machine (3) and a vehicle (2) including a hydrodynamic machine (3) are disclosed.

Claims

1. A sealing arrangement for a hydrodynamic machine, wherein the sealing arrangement is configured to seal a space between a shaft and a housing of the hydrodynamic machine, and wherein the sealing arrangement comprises: a sealing housing configured to be connected to the housing, and extending in a path surrounding the shaft; a first sealing ring configured to be connected to and extending in a path surrounding the shaft, wherein the first sealing ring comprises a first annular sealing surface; a second sealing ring arranged in and extending in a path surrounded by the sealing housing wherein the second sealing ring comprises a second annular sealing surface located and configured to sealingly abut against the first annular sealing surface in a first abutment interface; a coolant space adjacent to the first abutment interface; and the sealing housing comprises a wall protruding into the coolant space and the wall is configured to direct a flow of coolant in the coolant space.

2. The sealing arrangement according to claim 1, wherein the wall is integral of the sealing housing.

3. The sealing arrangement according to claim 1, wherein the sealing housing is configured such that the flow of coolant is directed around the wall.

4. The sealing arrangement according to claim 1, wherein the wall extends concentrically in relation to the second sealing ring.

5. The sealing arrangement according to claim 1, further comprising: a third sealing ring arranged in the sealing housing, the first sealing ring further comprises a fourth annular sealing surface; and the third sealing ring comprises a third annular sealing surface configured to sealingly abut against the fourth annular sealing surface.

6. The sealing arrangement according to claim 5, wherein the coolant space is open to contain coolant and the coolant space extends between the first abutment interface and a second abutment interface between the third and the fourth annular sealing surfaces.

7. The sealing arrangement according to claim 5, wherein the wall extends in the coolant space confined by the second and third sealing rings.

8. The sealing arrangement according to claim 5, wherein the sealing arrangement comprises one or more locking elements configured to lock the second and third sealing rings from rotating relative to the sealing housing.

9. The sealing arrangement according to claim 8, wherein the wall comprises at least one recess, and wherein the second and third sealing rings each comprises at least one recess, wherein each of the one or more locking elements extends into one respective recess of the wall and into one respective recess of the respective second and third sealing rings.

10. The sealing arrangement according to claim 9, wherein the recesses and the one or more locking elements are configured to allow a predetermined degree of rotation of the second and third sealing rings relative to the sealing housing.

11. The sealing arrangement according to claim 5, wherein the sealing housing comprises a first and a second annular cavity extending in a direction around the shaft, wherein each of the cavities is delimited by the wall, and wherein the second sealing ring is arranged in the first annular cavity, and the third sealing ring is arranged in the second annular cavity.

12. The sealing arrangement according to claim 5, wherein the sealing arrangement comprises spring elements located and configured to bias the second and third sealing rings towards the first sealing ring.

13. A hydrodynamic machine comprising a shaft, a housing around the shaft and a sealing arrangement according to claim 1, wherein the sealing arrangement is configured to seal a space between the shaft and the housing.

14. The hydrodynamic machine according to claim 13, wherein the hydrodynamic machine is a hydrodynamic retarder comprising a rotor connected to the shaft, and wherein the rotor is arranged in the housing.

15. A vehicle comprising a hydrodynamic machine according to claim 13.

16. A vehicle comprising a hydrodynamic machine according to claim 14.

17. The sealing arrangement of claim 1, further comprising a coolant inlet into and a coolant outlet from the coolant space for a flow of coolant through the coolant space.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Various aspects of the invention, including its particular features and advantages, will be readily understood from the example embodiments discussed in the following detailed description and the accompanying drawings, in which:

[0044] FIG. 1 illustrates a cross section of a portion of a hydrodynamic machine, according to some embodiments,

[0045] FIG. 2 illustrates an enlarged view of a cross section through a sealing arrangement of the hydrodynamic machine illustrated in FIG. 1,

[0046] FIG. 3 illustrates a second cross section through the sealing arrangement of the hydrodynamic machine illustrated in FIG. 1,

[0047] FIG. 4 illustrates a perspective view of a sealing housing of the sealing arrangement illustrated in FIG. 1-FIG. 3,

[0048] FIG. 5 illustrated a perspective view of two locking elements of the sealing arrangement illustrated in FIG. 1-FIG. 3,

[0049] FIG. 6 illustrates the locking elements illustrated in FIG. 5 positioned in recesses of a wall of the sealing housing illustrated in FIG. 4,

[0050] FIG. 7 illustrates a perspective view of a second and a third sealing ring of the sealing arrangement illustrated in FIG. 1-FIG. 3,

[0051] FIG. 8 illustrates a perspective view of a first and a second spring element, the locking elements, and the second and third sealing rings of the sealing arrangement according to the embodiments illustrated in FIG. 1-FIG. 7, and

[0052] FIG. 9 illustrates a vehicle according to some embodiments.

DETAILED DESCRIPTION

[0053] Aspects of the present invention will now be described more fully. Like numbers refer to like elements throughout. Well-known functions or constructions will not necessarily be described in detail for brevity and/or clarity.

[0054] FIG. 1 illustrates a cross section of a portion of a hydrodynamic machine 3, according to some embodiments. According to the illustrated embodiments, the hydrodynamic machine 3 is a hydrodynamic retarder configured to generate a braking torque that can be transferred to wheels of a vehicle, as is further explained herein. The hydrodynamic machine 3 comprises a rotor 60 connected to a shaft 7. The rotor 60 is arranged in the housing 9. The shaft 7 extends through an opening of the housing 9. A stator is arranged adjacent to the rotor 60. The stator is not illustrated in FIG. 1 for the reason of brevity and clarity. The rotor 60 and stator each comprises a multiplicity of shovels 4 which together form a workspace 6. The hydrodynamic machine 3 comprises a working medium circuit connected to the workspace. When retardation is required, working medium, such as oil, water, or a water mixture, is pumped into the workspace, and the viscous drag induced in the workspace 6 will generate the braking torque. During braking, the working medium will heat. According to some embodiments, working medium circuit is connected to a cooling circuit of an engine of the vehicle. According to such embodiments, the working medium may comprise a mixture of water and glycol. According to such embodiments, the hydrodynamic machine 3 may be referred to as a water retarder. The working medium may in these embodiments be cooled in heat exchanger of the cooling circuit of the engine of the vehicle, or in a separate heat exchanger arranged to dissipate the heat generated by the hydrodynamic machine 3.

[0055] The hydrodynamic machine 3 comprises a sealing arrangement 1 configured to seal a space 5 between a shaft 7 and a housing 9 of the hydrodynamic machine 3. The sealing arrangement 1 comprises a sealing housing 11 connected to the housing 9 of the hydrodynamic machine 3. According to the illustrated embodiments, the sealing housing 11 is a separate unit positioned in a seat of the housing 9 of the hydrodynamic machine 3. According to further embodiments, the sealing housing 11 may be integral of the housing 9 of the hydrodynamic machine 3. The sealing arrangement 1 comprises a first sealing ring 13 connected to the shaft 7. The first sealing ring 13 comprises a first annular sealing surface 13′. The sealing arrangement 1 further comprises a second sealing ring 15 arranged in the sealing housing 11.

[0056] FIG. 2 illustrates an enlarged view of a cross section through the sealing arrangement 1 of the hydrodynamic machine illustrated in FIG. 1. As indicated in FIG. 2, the second sealing ring 15 comprises a second annular sealing surface 15′ configured to sealingly abut against the first annular sealing surface 13′ of the first sealing ring 13 in a first abutment interface 17. The sealing arrangement 1 comprises a coolant space 19 adjacent to the first abutment interface 17. The coolant space 19 extends to a portion of the first abutment interface 17 and is configured to provide cooling and lubrication of the first abutment interface 17. According to the illustrated embodiments, the coolant space 19 is an annular coolant space extending around the entire inner circumference of the first abutment interface 17, and around the entire inner circumference of the second sealing ring 15. That is, according to the illustrated embodiments, the coolant space 19 is arranged such that coolant in the coolant space 19 is in contact with the entire inner circumference of the first abutment interface 17. The sealing housing 11 comprises a wall 21 protruding into the coolant space 19. The wall 21 is configured to direct a flow of coolant in the coolant space 19. In this manner, an improved cooling and an improved lubrication of the first abutment interface 17 is provided, as is further explained herein. Further, as can be seen in FIG. 2, the wall 21 is integral of the sealing housing 11. Thereby, the assembling of the sealing arrangement 1 is facilitated, as is further explained herein. The wall 21 extends concentrically in relation to the second sealing ring 15.

[0057] According to the illustrated embodiments, the sealing arrangement 1 comprises a third sealing ring 23 arranged in the sealing housing 11. The third sealing ring 23 has a smaller diameter than the second sealing ring 15 and is arranged concentrically to the second sealing ring 15. The first sealing ring 13 comprises a fourth annular sealing surface 13″. The third sealing ring 23 comprises a third annular sealing surface 23′ configured to sealingly abut against the fourth annular sealing surface 13″ of the first sealing ring 13. During operation of the hydrodynamic machine, the first sealing ring 13 will corotate with the shaft. The second and third sealing ring 13, 23 are stationary relative the sealing housing 11. The annular sealing surfaces 13′, 13″ of the first sealing ring 13 will thus slide relative the sealing surfaces 15′, 23′ of the second and third sealing rings 15, 23 during operation of the hydrodynamic machine. Each of the sealing surfaces 13′, 13″, 15′, 23′ of the first, second, and third sealing rings 13, 15, 23 comprises a hard material. The first, second, and third sealing rings 13, 15, 23 may be manufactured of ceramic, carbon, silicon carbide, or tungsten carbide or any equal hard material.

[0058] The coolant space 19 extends between the first abutment interface 17 and a second abutment interface 25 between the third and fourth annular sealing surfaces 23′, 13″. That is, the coolant space 19 is arranged adjacent to the second abutment interface 25 and extends to a portion of the second abutment interface 25. The coolant space 19 is configured to provide cooling and lubrication of the second abutment interface 25. According to the illustrated embodiments, the coolant space 19 extends around the entire outer circumference of the second abutment interface 25, and around the entire outer circumference of the third sealing ring 23. That is, according to the illustrated embodiments, the coolant space 19 is arranged such that coolant in the coolant space 19 is in contact with the entire outer circumference of the second abutment interface 25. Thus, according to the illustrated embodiments, the coolant space 19 provides cooling and lubrication of the first and second abutment interfaces 17, 25 in an efficient manner.

[0059] According to the illustrated embodiments, the wall 21 extends in a space confined by the second and third sealing rings 15, 23. Further, as will be further explained below, the sealing housing 11 is arranged such that the flow of coolant is directed around the wall 21. Further, as can be seen in FIG. 2, the sealing arrangement 1 comprises a first spring element 52 configured to bias the second sealing ring 15 towards the first sealing ring 13, and a second spring element 52 configured to bias the third sealing ring 23 towards the first sealing ring 13.

[0060] FIG. 3 illustrates a second cross section through the sealing arrangement 1 of the hydrodynamic machine illustrated in FIG. 1. The cross section illustrated in FIG. 3 is located at a different circumferential position of the sealing arrangement 1 than the cross section illustrated in FIG. 2. As indicated in FIG. 3, a first surface 21.1 of the wall 21 and a surface 15.1 of the second sealing ring 15 together delimit a first coolant passage portion 27 of the coolant space 19. Furthermore, a second surface 21.2 of the wall 21 and a surface 23.1 of the third sealing ring 23 together delimit a second coolant passage portion 29 of the coolant space 19.

[0061] The sealing arrangement 1 comprises coolant outlet 33 fluidly connected to the first coolant passage portion 27. Further, as can be seen in FIG. 2, the sealing arrangement 1 comprises coolant inlet 31. The coolant inlet 31 is arranged at a different circumferential position of the sealing arrangement 1 than the coolant outlet 33. The coolant inlet 31 illustrated in FIG. 2 is fluidly connected to the second coolant passage portion 29 indicated in FIG. 3. Below, simultaneous reference is made to FIG. 1-FIG. 3. The housing 9 of the hydrodynamic machine 3 comprises an inlet duct fluidly connected to the coolant inlet 31 of the sealing arrangement 1, and an outlet duct 32 fluidly connected to the coolant outlet 33 of the sealing arrangement 1.

[0062] In this manner, during operation of the hydrodynamic machine 3, coolant is pumped into the inlet 31 of the sealing arrangement 1, through the second coolant passage portion 29, around the wall 21 and into the first coolant passage portion 27. Since the coolant inlet 31 and the coolant outlet 33 are arranged at different circumferential positions, and since the coolant space 19 is annular, the coolant will also flow around the circumference of the coolant space 19. Thereby, an improved cooling and an improved lubrication of the first and second abutment interfaces 17, 25 is provided. In addition, the slight overpressure in the coolant space 19 may provide a controlled leakage of coolant through the respective first and second abutment interfaces 17, 25. In this manner, an improved cooling and an improved lubrication of the annular sealing surfaces 13′, 15′, 23′, 13″ is provided. The coolant in the coolant space 19 may be coolant of a type used as working medium in the workspace 6 of the hydrodynamic machine 3, for example a mixture of water and glycol. Coolant leaking from the coolant space 19 through the first abutment interface 17 will leak into the workspace 6 of the hydrodynamic machine 3 and can thus be pumped from the workspace 6 by the pumping action of the rotor 60. As indicated in FIG. 1, the hydrodynamic machine comprises a drainage channel 34. Coolant leaking from the coolant space 19 through the second abutment interface 25 is evacuated through the drainage channel 34.

[0063] FIG. 4 illustrates a perspective view of the sealing housing 11 of the sealing arrangement 1 illustrated in FIG. 1-FIG. 3. As indicated in FIG. 4, the sealing housing 11 comprises a first and a second annular cavity 41, 42 each delimited by the wall 21. The second sealing ring is configured to be arranged in the first annular cavity 41, and the third sealing ring is configured to be arranged in the second annular cavity 42. The coolant outlet 33 is fluidly connected to the first annular cavity 41. The coolant inlet 31, indicated in FIG. 2 is fluidly connected to the second annular cavity 42, indicated in FIG. 4. Further, as can be seen in FIG. 4, the wall 21 comprises two recesses 37, 37′ arranged at different circumferential positions of the wall 21.

[0064] FIG. 5 illustrated a perspective view of two locking elements 35, 35′ of the sealing arrangement illustrated in FIG. 1-FIG. 3. The two locking elements 35, 35′ are connected by a first annular connecting element 45, and by a second annular connecting element 47. The first and second annular connecting elements 45, 47 are concentrically arranged, and the first annular connecting element 45 is arranged on a radial outside of the second annular connecting element 47. According to the illustrated embodiments, the first connecting element 45, the second connecting element 47, and the one or more locking elements 35, 35′ are formed by one coherent piece of material. The first connecting element 45, the second connecting element 47, and the one or more locking elements 35, 35′ may be formed by a polymeric material, or a metal material, such as aluminium.

[0065] FIG. 6 illustrates the locking elements 35, 35′ illustrated in FIG. 5 positioned in the recesses 37, 37′ of the wall 21 of the sealing housing 11 illustrated in FIG. 4. As can be seen in FIG. 6, when the two locking elements 35, 35′ are be positioned in the recesses 37, 37′ of the wall 21, the first connecting element 45 is arranged in the first annular cavity 41, and the second connecting element 47 is arranged in the second annular cavity 42. Further, in FIG. 6, the coolant inlet 31 can be seen, which, as mentioned, is fluidly connected to the second annular cavity 42.

[0066] FIG. 7 illustrates a perspective view of the second and third sealing rings 15, 23 of the sealing arrangement 1 illustrated in FIG. 1-FIG. 3. As can be seen in FIG. 7, the second and third sealing rings 15, 23 each comprises two recesses 39, 39′ arranged at different circumferential positions of the respective sealing ring 15, 23. The recesses 39, 39′ are made in a surface 40, 40′ of the respective second and third sealing ring 15, 23 opposite to the annular sealing surface 15′, 23′ of the respective second and third sealing ring 15, 23, i.e. in a surface 40, 40′ of the respective second and third sealing ring 15, 23 facing away from the first sealing ring 13 when the sealing arrangement 1 is assembled, as is illustrated in FIG. 1-FIG. 3.

[0067] Below, simultaneous reference is made to FIG. 4-FIG. 7. The second and third sealing rings 15, 23 are configured to be positioned in the first and second annular cavities 41, 42, such that the recesses 39, 39′ each receives a locking element 35, 35′. When the sealing element is assembled, each locking element 35, 35′ extends into one recess 37, 37′ of the wall 21 and into one recess 39, 39′ of the respective second and third sealing rings 15, 23. In this manner, the locking elements 35, 35′ will lock the second and third sealing rings 15, 23 from rotating relative the sealing housing 11. The locking elements 35, 35′ may be configured to allow a predetermined degree of rotation of the second and third sealing rings 15, 23 relative the sealing housing 11, and may be provided in a material providing damping of the rotation of the second and third sealing rings 15, 23 relative the sealing housing 11. Such material may for example comprise a polymeric material. Further, due to the functions and features explained above, the sealing arrangement can be assembled in a simple and cost-efficient manner, as is further explained below.

[0068] The sealing arrangement 1 may comprise another number of locking elements 35, 35′ than two, such as one, three, four, five, or six. According to such embodiments, the wall 21 may comprise a corresponding number of recesses 37, 37′, and the second and third sealing rings 15, 23 may each comprise a corresponding number of recesses 39, 39′, such that when the sealing element is assembled, each locking element 35, 35′ extends into one recess 37, 37′ of the wall 21 and into one recess 39, 39′ of the respective second and third sealing rings 15, 23.

[0069] FIG. 8 illustrates a perspective view of the first and the second spring elements 51, 52, the locking elements 35, 35′, and the second and third sealing rings 15, 23 of the sealing arrangement 1 according to the embodiments illustrated in FIG. 1-FIG. 7. As can be seen in FIG. 8, according to these embodiments, the first and second spring elements 51, 52 each comprises a coil spring. Below, simultaneous reference is made to FIG. 1-FIG. 8. The first spring element 51 has a diameter matching the diameter of the first annular cavity 41. The second spring element 52 has a diameter matching the diameter of the second annular cavity 42.

[0070] In an assembling process of the sealing arrangement 1, an assembler may position the first spring element 51 in the first annular cavity 41 of the sealing housing 11, and may position the second spring element 52 in the second annular cavity 42 of the sealing housing 11. Then, the assembler may position the locking elements 35, 35′ in the recesses 37, 37′ of the wall 21 of the sealing housing 11. Then, the assembler may position the second sealing ring 15 in the first annular cavity 41 such that the recesses 39 of the second sealing ring 15 each receives a locking element 35, 35′. Then, the assembler may position the third sealing ring 23 in the second annular cavity 42 such that the recesses 39′ of third sealing ring 23 each receives a locking element 35, 35′. In this manner, the sealing arrangement 1 can be assembled in a quick, simple and cost-efficient manner.

[0071] Further, as can be seen in FIG. 8, according to the illustrated embodiments, the spring elements 51, 52 are configured to bias the one or more locking elements 35, 35′ towards the second and third sealing rings 15, 23. In this manner, it is ensured that the locking elements 35, 35′ are kept in place in the recesses 39, 39′ of the second and third sealing rings 15, 23.

[0072] As best seen in FIG. 6, the locking elements 35, 35′ each extends in a radial direction of the sealing arrangement 1. In addition, as best seen in FIG. 6, the first and second connecting elements 45, 47 may each contribute in keeping the locking elements 35, 35′ in a substantially straight radial direction during operation of the hydrodynamic machine, which reduces the risk of a dislocation of the respective locking element 35, 35′. However, according to some embodiments, the first and second connecting elements 45, 47 may each comprise a flexible material allowing a predetermined degree of dislocation of the respective locking element 35, 35′, i.e. a predetermined degree of rotation of the respective locking element 35, 35′, so as to allow a predetermined degree of relative rotation between the second and third sealing rings 15, 23. In this manner, a more durable sealing arrangement 1 is provided because a predetermined degree of relative rotation between the second and third sealing rings 15, 23 is allowed for during rapid changes in rotational velocity of the shaft, occurring for example during start-up phases of the hydrodynamic machine.

[0073] Furthermore, according to the illustrated embodiments, the locking elements 35, 35′ are retained and contained in the sealing housing 11 when the sealing arrangement 1 is assembled and does not extend through openings in outer walls of the sealing housing 11. As a result thereof, the assembling process of the sealing arrangement 1 is facilitated and a more leak proof sealing arrangement 1 is provided.

[0074] Further, as best seen in FIG. 2, according to the illustrated embodiments, the first connecting element 45 of the locking elements 35, 35′ is arranged adjacent to the first spring element 51 in the first annular cavity 41. Furthermore, the second connecting element 47 is arranged adjacent to the second spring element 52 in the second annular cavity 42. In this manner, the connecting elements 45, 47 act as guides for the spring elements 51, 52 which reduces the risk of a misalignment of the spring elements 51, 52.

[0075] FIG. 9 illustrates a vehicle 2 according to some embodiments. The vehicle 2 comprises a hydrodynamic machine 3 according to the embodiments illustrated in FIG. 1. The vehicle 2 comprises wheels 54 and a power source 56 configured to provide motive power to the vehicle 2, via one or more wheels 54 of the vehicle 2. The hydrodynamic machine 3 is configured to selectively generate a braking torque to one or more wheels 54 of the vehicle 2.

[0076] According to the illustrated embodiments, the vehicle 2 is a truck. However, according to further embodiments, the vehicle 2, as referred to herein may be another type of manned or unmanned vehicle for land or water based propulsion such as a lorry, a bus, a construction vehicle, a tractor, a car, a ship, a boat, or the like.

[0077] It is to be understood that the foregoing is illustrative of various example embodiments and that the invention is defined only by the appended claims. A person skilled in the art will realize that the example embodiments may be modified, and that different features of the example embodiments may be combined to create embodiments other than those described herein, without departing from the scope of the present invention, as defined by the appended claims.

[0078] As used herein, the term “comprising” or “comprises” is open-ended, and includes one or more stated features, elements, steps, components or functions but does not preclude the presence or addition of one or more other features, elements, steps, components, functions or groups thereof.