阅读说明：本技术 具有冷却的密封系统的减速器 (Retarder with cooled sealing system ) 是由 D.劳克曼 R.谢德 W.亚当斯 M.迪特斯 T.尼斯 于 2021-03-17 设计创作，主要内容包括：所建议的发明涉及一种液力减速器,包括减速器壳体、减速器轴和密封系统。减速器轴具有布置在减速器壳体以外的第一局部段和布置在减速器壳体以内的第二局部段。密封系统布置在减速器壳体和减速器轴之间,使得减速器壳体内的与工作介质循环回路相连的内部空间相对于环境被流体密封地密封。密封系统包括至少一个第一密封元件和至少一个第二密封元件,并且在密封元件之间设有密封室。密封室通过布置在减速器轴中的第一通道直接与工作介质循环回路连接。为了改善对密封系统的润滑和冷却,按照本发明建议,密封室通过至少局部区段地在减速器壳体中延伸的第二通道直接与工作介质循环回路连接或可连接,使得当减速器轴旋转时,密封室被辅助流穿流。(The proposed invention relates to a hydrodynamic retarder comprising a retarder housing, a retarder shaft and a sealing system. The gear unit shaft has a first partial section arranged outside the gear unit housing and a second partial section arranged inside the gear unit housing. The sealing system is arranged between the gear housing and the gear shaft, so that an interior space in the gear housing, which is connected to the working medium circuit, is sealed fluid-tightly from the environment. The sealing system comprises at least one first sealing element and at least one second sealing element, and a sealing chamber is provided between the sealing elements. The seal chamber is directly connected to the working medium circuit via a first channel arranged in the retarder shaft. In order to improve the lubrication and cooling of the sealing system, it is proposed according to the invention that the sealing chamber is directly connected or connectable to the working medium circuit via a second channel which extends at least in some sections in the gear housing, so that the sealing chamber is flowed through by an auxiliary flow when the gear shaft rotates.)

1. A hydrodynamic retarder (1) comprising a retarder housing (8), a retarder shaft (5) and a sealing system (2), wherein the retarder shaft (5) has a first partial section (9) arranged outside the retarder housing (8) and a second partial section (10) arranged inside the retarder housing (8),

wherein the sealing system (2) is arranged between the gear housing (8) and the gear shaft (5) in such a way that an interior space (11) in the gear housing (8) connected to the working medium circuit (4) is sealed in a fluid-tight manner from the environment,

wherein the sealing system (2) comprises at least one first sealing element (12b) and at least one second sealing element (13), and a sealing chamber (14) is provided between the sealing elements (12b, 13),

wherein the seal chamber (14) is directly connected or connectable to the working medium circuit (4) via a first channel (15) arranged in the retarder shaft (5),

the device is characterized in that the sealing chamber (14) is directly connected or connectable to the working medium circuit (4) via a second channel (16) extending at least in sections in the retarder shaft (5) such that, when the retarder shaft (5) rotates, the auxiliary flow (19) can flow into the sealing chamber (14) via the first channel (15) and can be returned from the sealing chamber (14) via the second channel (16) after flowing through the sealing chamber (14).

2. A hydrodynamic retarder (1) comprising a retarder housing (8), a retarder shaft (5) and a sealing system (2), wherein the retarder shaft (5) has a first partial section (9) arranged outside the retarder housing (8) and a second partial section (10) arranged inside the retarder housing (8),

wherein the sealing system (2) is arranged between the gear housing (8) and the gear shaft (5) in such a way that an interior space (11) in the gear housing (8) connected to the working medium circuit (4) is sealed in a fluid-tight manner from the environment,

wherein the sealing system (2) comprises at least one first sealing element (12b) and at least one second sealing element (13), and a sealing chamber (14) is provided between the sealing elements (12b, 13),

wherein the seal chamber (14) is directly connected or connectable to the working medium circuit (4) via a first channel (15) arranged in the retarder shaft (5),

characterized in that the sealing chamber (14) is directly connected or connectable to the working medium circuit (4) via a second channel (16) extending at least in some sections in the gear housing (8) such that the sealing chamber (14) is traversed by an auxiliary flow (19) when the gear shaft (5) rotates.

3. A hydrodynamic retarder according to claim 1 or 2, characterized in that the first sealing element comprises at least one radial shaft sealing ring (12b) and the second sealing element is a rectangular sealing ring (13).

4. A hydrodynamic retarder according to claim 1 or 2, characterized in that the second channel (16) is connected or connectable in fluid communication with an inlet chamber (20) in the working medium circuit (4).

5. Hydrodynamic retarder according to claim 1 or 2, characterized in that a pump (18) is arranged in the first (15) or second (16) channel, wherein the volume flow of the secondary flow (19) through the seal chamber (14) can be adjusted by means of the pump (18).

6. A hydrodynamic retarder according to claim 4, characterized in that an auxiliary flow (19) can be generated by means of the pump (18), wherein a working medium (21) from a working medium container (22) is fed into the sealing chamber (14) via the first channel (15).

7. A hydrodynamic retarder according to claim 5, characterized in that an auxiliary flow (19) can be generated by means of the pump (18), wherein working medium (21) from a working medium container (22) is sucked into the sealing chamber (14) via the first channel (15).

8. Hydrodynamic retarder according to claims 3 and 5, characterized in that the pump (18) is designed such that, in non-braking operation, a leakage flow (25) is fed from the sealing chamber (14) via the second sealing element, the rectangular sealing ring (13), into the working chamber.

9. Hydrodynamic retarder according to claims 3 and 5, characterized in that the pump (18) is designed such that, in non-braking operation, a leakage flow (25) is conveyed from the working chamber into the sealing chamber (14) via the second sealing element, the rectangular sealing ring (13).

10. A hydrodynamic retarder according to claim 1, characterized in that the second channel (16) in the shaft (5) comprises two transverse channel sections (17b, c), wherein the shaft (5) has a smaller shaft diameter in the region of the inlet of the first transverse channel section (17b) than in the region of the outlet of the second transverse channel section (17b), the working medium entering the first transverse channel section (17b) through the region of the inlet and being discharged from the second transverse channel (17c) through the region of the outlet.

11. Hydrodynamic retarder according to claim 2, characterized in that the second channel (16) is connected or connectable in fluid communication with a working medium container (22) in the working medium circuit (4).

12. A hydrodynamic retarder according to claim 2, characterized in that the second channel (16) is connected or connectable in fluid communication with a ventilation channel (23) in the working medium circuit (4).

Technical Field

The invention relates to a hydraulic retarder.

Background

Hydrodynamic retarders are known which have a working chamber which can be filled with a working medium in order to transmit the torque of a driven primary impeller, also referred to as the rotor, to a stationary secondary impeller, also referred to as the stator. The retarder is connected to a retarder working medium circulation circuit in which a working medium such as oil or cooling water of a vehicle cooling circulation circuit can circulate.

For the reduction gear, two operating states are basically distinguished: a braking mode in which the working chamber is filled with working medium and a non-braking mode in which the working chamber is emptied, except for a small remaining working medium volume. In braking operation, the braking torque can also be adjusted by the degree of filling.

The rotor is coupled in a rotationally fixed manner to a rotor shaft, via which the braking torque is transmitted to the vehicle wheels. The rotor shaft can be driven, for example, by a transmission output shaft or a shaft (cardan shaft) which is connected in a rotationally fixed manner to the drive wheels of the motor vehicle. In many motor vehicles, the retarder is directly flanged to the transmission and is driven via a high-speed gear (Hochtrieb), a gear transmission. The high-speed transmission is integrated in and lubricated and cooled by a transmission oil circulation circuit. A sealing system is arranged between the transmission oil circulation circuit and the retarder working medium circulation circuit, and the sealing system separates oil of the transmission oil circulation circuit from the working medium of the retarder working medium circulation circuit.

This separation is usually achieved in that a first sealing lip of the sealing system is cooled and lubricated by means of transmission oil and a second sealing lip is cooled and lubricated by means of a flow of working medium, oil or water.

The sealing system may be constituted by two radial shaft sealing rings RWDR and one rectangular ring as shown in patent document CN 105673735 a 1. When the retarder shaft rotates, an oil flow is conveyed via a channel in the retarder shaft to the rotor-side radial shaft sealing ring, i.e. between the second sealing lip and the rectangular ring, so that both seals are lubricated and thus also cooled.

As described above, two operating states are basically distinguished: a braking operation and a non-braking operation. Since the reduction gear shaft rotates in both operating states, it is necessary in both operating states to lubricate and cool the sealing points by means of a flow of oil. In braking operation, due to the high pressure in the working chamber, the leakage oil flow is pressed through the rectangular ring, rectangular ring RER seal, so that the leakage oil flow reaches the seal. The relatively hot oil thus comes into contact with the radial shaft sealing ring, in particular the second sealing lip, on the transmission side and is conducted from there via a channel in the transmission shaft back into the transmission working medium circuit. The retarder shaft is heated by the relatively hot oil, and the service life of the two radial shaft sealing rings is therefore adversely affected.

Patent document CN 105909696 a1 also discloses a lubrication method for cooling and lubricating the sealing system of a retarder in non-braking operation, wherein a working medium, oil, is pumped by means of a pumping device through the retarder shaft, through a transverse bore to a retarder-side sealing lip of a radial shaft sealing ring and then through a passage between the rotor housing and the rotor back into the retarder working medium circulation circuit.

DE 202005003329U 1 discloses a retarder system with a sealing system. At least some of the sealing elements are designed such that a leakage flow can flow through them during braking operation and also during non-braking operation.

Furthermore, DE 102011115033B 3 discloses a gear unit with a sealing system, wherein channels are provided in the gear unit shaft, which enable the supply of a working medium in order to lubricate the seals of the sealing system.

Disclosure of Invention

The object of the invention is to improve the working medium circuit in such a way that the lubrication and cooling of the sealing system is improved.

The object is achieved according to the invention by a hydrodynamic retarder.

The proposed embodiment relates to a hydrodynamic retarder, comprising a retarder housing, a retarder shaft and a sealing system, wherein the retarder shaft has a first partial section arranged outside the retarder housing and a second partial section arranged inside the retarder housing. Furthermore, the sealing system is arranged between the gear housing and the gear shaft, so that an interior space in the gear housing, which is connected to the working medium circuit, is sealed fluid-tightly from the environment. The sealing system comprises at least one first sealing element and at least one second sealing element, and a sealing chamber is provided between the sealing elements, wherein the sealing chamber is directly connected or connectable with the working medium circuit via a first channel arranged in the gear shaft.

In order to improve the lubrication and cooling of the sealing system, it is proposed according to the invention that the sealing chamber is directly connected or connectable to the working medium circuit via a second channel which extends at least in some sections in the transmission shaft, so that when the transmission shaft rotates, the auxiliary flow can flow into the sealing chamber via the first channel and can be returned from the sealing chamber via the second channel after flowing through the sealing chamber.

According to the invention, it is also proposed that the seal chamber is connected or connectable directly to the working medium circuit via a second channel which extends at least in some sections in the gear housing, so that the seal chamber is flowed through by the auxiliary flow when the gear shaft rotates.

The structure having the first channel as the input channel and the second channel as the output channel realizes: the secondary flow can be generated and the sealing chamber is flowed through by the working medium, which allows the sealing region, in particular the gear unit shaft, to be cooled better.

In a preferred embodiment, the first sealing element comprises at least one radial shaft sealing ring and the second sealing element is a rectangular sealing ring. Furthermore, it is advantageous if the first sealing element consists of two radial shaft sealing rings, wherein the sealing lips are preferably oriented opposite one another.

In a preferred embodiment, the second channel is connected or connectable to an inlet chamber of the retarder. The inlet chamber is a space in the working medium circuit, through which the working medium is guided during braking operation before entering the annular working chamber between the rotor and the stator.

Furthermore, a pump can be provided, which is arranged in the first or second channel, wherein the volume flow of the secondary flow through the sealing chamber can be adjusted by means of the pump. Basically, two pump arrangements can be realized here.

In a first embodiment, the pump is arranged such that an auxiliary flow can be generated by means of the pump, wherein the working medium from the working medium container is conveyed into the sealing chamber via the first channel. Via a second channel in the gear shaft, the working medium is again discharged from the seal chamber and from there returned into the working medium circuit. In this embodiment, the pumping action of the pump is supported by the pumping action of the transverse bore in the reducer shaft, wherein here the transverse bore forms a partial section of the first channel.

The section of the second channel leading through the reduction gear shaft may preferably consist of two further transverse channel sections and a longitudinal section, wherein the pumping actions of the transverse channel sections counteract one another, so that the working medium is more easily returned into the chamber via the second channel.

However, there is also the option of arranging a pump in the second channel and generating an auxiliary flow by means of the pump, wherein the working medium from the working medium container is sucked into the seal chamber via the first channel and is sucked out of the seal chamber again via the second channel section in the gear unit shaft. In this option, the pump is arranged in the second channel before the inlet chamber, so that the working medium is pumped back into the working medium circulation circuit via the inlet chamber. In addition, the suction power of the pump in this configuration is designed to convey sufficient working medium from the working medium reservoir through the seal chamber, at least in the non-braking mode.

Preferably, in both options, the pump is designed to generate a leakage flow through the second sealing element, i.e. the rectangular sealing ring, in non-braking operation.

In a first alternative, the pump is preferably designed such that, in the non-braking mode, a leakage flow is conveyed from the sealing chamber via (14) to the working chamber by the second sealing element, i.e. the rectangular sealing ring.

In a second alternative, the pump is preferably designed such that, in non-braking operation, a leakage flow is conveyed from the working chamber into the sealing chamber via the second sealing element, i.e. the rectangular sealing ring.

In order to improve the pumping action achieved by the second channel with two transverse channel sections in the shaft, it is furthermore proposed that the shaft diameter of the shaft in the region of the inlet of the first transverse channel section is smaller than the shaft diameter in the region of the outlet of the second transverse channel section, the working medium enters the first transverse channel section through the region of the inlet and is discharged from the second transverse channel through the region of the outlet.

In a preferred embodiment, it is also provided that the second channel is connected or connectable in a fluid-conducting manner to a working medium container in the working medium circuit.

In a preferred embodiment, it is also provided that the second channel is connected or connectable in a fluid-conducting manner to a ventilation channel in the working medium circuit.

Drawings

Further advantageous features of the invention are explained with the aid of embodiments with reference to the drawings. In the drawings:

FIG. 1 illustrates a retarder according to the prior art;

FIG. 2 illustrates a sealing system according to the prior art;

FIG. 3 shows a first embodiment;

FIG. 4 shows a second embodiment;

5-8 illustrate an alternative embodiment having a return passage through the housing;

Detailed Description

Fig. 1 and 2 show sectional views from which the structure of a retarder 1 according to the prior art can be seen. The main structure of the retarder is shown in fig. 1, and the sealing system known from the prior art is shown in detail in fig. 2.

The section shown in fig. 1 shows a transmission 1 with a transmission housing 8, which is fixed in or on the transmission housing. The transmission shaft 5 projects with its first partial section 9 into the transmission housing 28, which is arranged at least partially outside the transmission housing 8. All components not located in the inner space 11 of the transmission case 8, such as the bearing 30 and the seal 12a of the seal system 2, are in contact with or lubricated by the oil of the transmission oil circulation circuit 3.

The second partial section 10 of the gear unit shaft 5 is arranged in the gear unit housing 8. All components in the gear housing 8 are in contact with the working medium of the gear 1 and are lubricated and cooled by it. The working medium may be oil or cooling water from a cooling circuit. The interior space of the gear housing 8 comprises all channels and chambers through which the working medium can flow.

Between the first and second partial section 9, 10 of the transmission shaft 5, a sealing system 2 is arranged, which separates the transmission oil circuit 3 from the working medium circuit 4.

The gear unit shaft 5 is rotatably mounted relative to the gear unit housing 5 by means of bearings 30, and the rotor 6 is mounted on the gear unit shaft 5 in such a way that, when the working chamber 32 is filled with working medium, the rotor 6 is axially displaced in the direction of the stator, and, as soon as the working position is reached, a braking torque is transmitted to the gear unit shaft 5. The function of the movable rotor is to serve as a reducer of the general prior art.

Two main operating states are distinguished for the retarder: the non-braking operation and the braking operation with the working chamber filled with working medium are shown in fig. 1. In order to carry out the braking operation, the working medium is conveyed from the working medium container 22 into the working medium circuit 4 by a not shown pressurization device, wherein the degree of filling of the working chamber is adjustable.

Fig. 2 shows a sealing system 2 consisting of a plurality of sealing elements 12a, b and 13. A sealing chamber 14 is provided between the sealing elements 12b and 13, wherein the sealing chamber 14 is connected or connectable to the working medium circuit 4 via a first channel 15 arranged in the transmission shaft 5. The first channel 15 is formed by a longitudinal channel section in the reduction gear shaft 5, which is designed as a blind hole, and a transverse channel 17a, which represents the connection between the seal chamber 14 and the blind hole.

These transverse channels 17a act like a pump when the retarder shaft 5 rotates, so that once the retarder shaft 5 rotates, the working medium is pumped into the seal chamber. The sealing elements 12a, b are designed as radial shaft sealing rings, the sealing lips of which are oriented opposite one another. The third sealing element is a rectangular sealing ring 13. The rectangular sealing ring 13 is designed such that a leakage flow 25 can be realized, which changes its direction in each case as a function of the operating state.

In fig. 3 and 4, two options of how the lubrication and cooling of the sealing system can be achieved are shown. In both embodiments, in addition to the first channel 15 in the retarder shaft 5, a second channel 16 is arranged in the retarder shaft 5.

The first channel 15 is designed as in the prior art. The second channel 16 extends in sections parallel to the first channel 15 and comprises at both ends a transverse channel section 17b, c, wherein the transverse channel section 17b is connected to the sealing chamber 14 and the second transverse channel section 17c is coupled to a connecting channel 24 which connects the second channel 16 to the inlet chamber 20.

Fig. 3 shows a first possible embodiment, in which a pump 18 is arranged in the first channel 15. The illustrated channel section between the pump 18 and the working medium container 22 is designated as the first channel 15.

The pump 18 is coupled in a rotationally fixed manner to the retarder shaft 5, so that the working medium is pumped into the seal chamber 14 each time the shaft rotates. In the braking mode, the pressure in the working chamber 32 is greater than the pressure in the sealing chamber 14, so that a leakage flow 25 is generated which flows through the sealing gap of the sealing element 13 and in the direction of the sealing chamber 14. The leakage flow 25 meets the auxiliary flow 19 in the sealing chamber 14 and is fed back into the working medium circuit 4 via the second channel 16.

In non-braking operation, which is not shown, there are other different pressure situations in which the leakage flow 25 reverses direction, since the pump 18 is designed such that in non-braking operation the pump pressure is greater than the pressure in the working chamber 32, which pressure is generated by the remaining amount of working medium in the working chamber. In non-braking operation, excess working medium from the working chamber 32 is pumped back into the working medium reservoir 22 via the bypass line 31.

Fig. 4 shows an alternative embodiment in the non-braking mode, in which the pump 18 is arranged in the connecting channel 24 between the second channel 16 and the inlet chamber 20, wherein the connecting channel 24 is a partial section or a continuation of the second channel 16. In this embodiment, the leakage flow 25 flowing through the sealing element 13 has the same direction in the braking mode and in the non-braking mode, since in both operating modes the pump 18 draws the working medium out of the sealing chamber and feeds it back into the working chamber 32 or the working medium circuit via the inlet chamber 20.

In both embodiments shown, the second channel may also be connected to a ventilation channel 23. A further alternative is the connection to the working medium container. In this option, it is necessary to provide a non-return valve in the connecting channel, so that the secondary flow 19 can flow only in the direction of the working medium container.

In fig. 3 and 4, the retarder shaft 5 and the channel extending therein are not shown in detail. Preferably, the passage section 16 is designed by the gear shaft 5 in such a way that the pumping action is effected in the desired direction through the second passage 16 with two transverse passage sections 17b, c in the shaft. For this purpose, the shaft diameters in the region of the inlet and outlet are dimensioned differently. In this way, the shaft diameter of the shaft in the inlet region of the first transverse channel section 17b is smaller than the shaft diameter in the outlet region of the second transverse channel section 17b, through which the working medium enters the transverse channel section 17b and through which the working medium exits the second transverse channel 17 c.

Fig. 5 to 8 show an alternative embodiment with only one passage in the transmission shaft 5 and an alternative return passage for the working medium in the circuit, in particular via the transmission housing 8.

Fig. 5 shows an embodiment in which the second channel 16 connects the seal chamber 14 with the inlet chamber 20. The figure shows the braking operation of the retarder, which can be seen symbolically by a slightly thicker line of the working medium circuit. The main volume flow of the working medium, here oil, is pumped from the working chamber to the cooler and back to the working chamber by means of the pumping action of the retarder.

In this embodiment, the auxiliary flow 19 is generated by means of the pumping action of the transverse bore in the reducer shaft 5. In this way, oil is drawn from the lower region of the working medium container 22 and introduced into the seal chamber 14 as an auxiliary flow 19. There, the auxiliary flow is mixed with the oil which is conveyed in the direction of the sealing chamber 14 as a leakage flow 25. Both flows are fed back into the working medium circuit 4 via the second channel 16 and the inlet chamber 20. The volume flow of the secondary flow 19 can be regulated by means of a throttle 26a and/or 26b and a check valve 27b can be provided in the second channel 16.

Fig. 6 shows an embodiment with a second channel 16 between the sealing chamber 14 and the working medium container 22. In this case, the auxiliary flow 19 is simply fed back into the upper region of the working medium container 22. The figure shows the volume flow in non-braking operation, wherein the auxiliary flow 19 is shown as a slightly thicker line.

Fig. 7 shows an embodiment with a second passage between the sealed chamber and the ventilation channel 23. As an alternative to the ventilation channel 23, a separate central channel can also be provided, which, like the ventilation channel 23, is connected to the center of the annular working chamber 32. In both embodiments, the secondary flow 19 is fed back into the working medium circuit via the channel 23 via the center of the working chamber 32.

Fig. 8 shows a further alternative embodiment, in which the second channel is designed as a suction channel, by means of which the working medium from the working medium container 22 is sucked into the seal chamber 14. A pumping action is generated by means of the pump 18. The suction effect is designed in such a way that in each operating state the working medium is sucked out of the seal chamber 14 against the pumping effect of the transverse channel 17 in the gear unit shaft 5. The working medium sucked out by the pump 18 is pumped back into the inlet chamber 20 and from there back into the working medium circuit. Since the suction pump generates a certain negative pressure in the sealing chamber 14, the leakage flow 25 in this embodiment has the same direction in both operating states, i.e. from the working chamber 32 into the sealing chamber 14.

In all the embodiments according to fig. 3 to 8, a bypass line 31 is also provided, which ensures that the working medium is pumped back from the working chamber into the working medium circuit also in non-braking operation. For this reason, the pumping action also always comes from the retarder itself in non-braking operation. In the non-braking mode, the check valve 27a prevents the working medium from flowing back into the working chamber.

List of reference numerals

1 speed reducer

2 sealing system

3 Transmission oil circulation Circuit

4 working medium circulation circuit

5 reducer shaft

6 rotor

7 stator

8 reducer casing

9 first partial section

10 second partial section

11 inner space

12a, b radial shaft seal ring

13 rectangular sealing ring

14 sealed chamber

15 first channel

16 second channel

17a, b, c transverse channel

18 pump

19 subsidiary flow

20 into the chamber

21 working medium

22 working medium container

23 Ventilation channel

24 connecting channel

25 leakage flow

26a, b throttle valve

27a, b check valve

28 Transmission housing

29 cooler

30 bearing

31 bypass line

32 working chambers.