CN113646552A

CN113646552A - Drive device for a trench wall cutter

Info

Publication number: CN113646552A
Application number: CN202080021855.6A
Authority: CN
Inventors: 罗兰·威德曼; 约翰尼斯·哈尔德; 斯特凡·杜利
Original assignee: Liebherr Components Biberach GmbH
Current assignee: Liebherr Components Biberach GmbH
Priority date: 2019-03-25
Filing date: 2020-03-05
Publication date: 2021-11-12
Anticipated expiration: 2040-03-05
Also published as: CN113646552B; DE102019111774A1; EP3927986A1

Abstract

The invention relates to a drive for a trench wall cutter (1), comprising a hydraulic motor (8), a transmission (9) which can be connected on the output side to at least one cutting wheel (3) of the trench wall cutter, and a drive shaft (12) which connects the hydraulic motor to the transmission, wherein the drive shaft is supported by at least one drive shaft bearing (25) arranged between the hydraulic motor and the transmission, wherein the drive shaft bearing has a lubricant inlet (14) which is connected to a leakage outlet of the hydraulic motor and/or to a hydraulic circuit for operating the hydraulic motor and is designed to lubricate the drive shaft bearing with a lubricant.

Description

Drive device for a trench wall cutter

Technical Field

The invention relates to a cutting machine for a trench wall

The drive device of (a), which comprises a hydraulic motor, a transmission connectable at the output side to at least one cutting wheel of the trench wall cutter, and a drive shaft connecting the hydraulic motor to the transmission, wherein the drive shaft is supported by at least one drive shaft bearing arranged between the hydraulic motor and the transmission. The invention also relates to a trench wall cutter with such a drive.

Background

Trench wall cutters are commonly used in particular civil engineering to cut trenches in the ground, rock or ground, which trenches are filled with a suspension containing, for example, concrete for forming the trench walls. Such trench walls are usually wall structures in foundations, for example made of concrete, reinforced concrete or the like, in order to seal, support or generally influence the foundation in a specific manner. To manufacture such a trench wall, a substantially vertical, upwardly open trench is cut using a trench wall cutter, wherein a cutting tool is lowered from above into the ground and guided by a preferably movable carrying device (e.g. a crawler-type cable excavator) supported on the ground. In this case, trench wall cutters generally comprise an elongate, vertical cutting frame which is suspended vertically movably on a carrier and carries at its lower end primarily a plurality of cutting wheels which can be driven in opposite directions about each horizontal axis. A drive for rotationally driving the cutting wheel may also be mounted at a lower portion of the cutting frame and for example comprise one or more hydraulic motors which may drive the cutting wheel through one or more transmission stages.

While the trench is continuously stabilized by the supporting suspension (St ü tzsubsion), the excavated soil material can be pumped to the surface by means of a muck pump, so that the trench or the trench walls do not collapse. After the desired depth is reached, the trench is then typically concreted.

The distance between the hydraulic motor and the transmission realized by the drive shaft enables a compact construction. In particular, if the support plate is constructed narrow in the desired manner, space problems on the support plate can be avoided. In particular, the hydraulic motor may be arranged above a support plate to which the cutting wheel is rotatably mounted, so that the mounting depth in the region of the cutting wheel can be kept small.

However, with such spacing and arrangement of the hydraulic motors, there are lubrication problems. When the main components of the transmission, in particular the planet gears, the sun gear and the planet carrier thereof, are lubricated in the region of the gearbox by a sump lubrication system, in particular the drive shaft bearing supporting the drive shaft between the hydraulic motor and the transmission is located outside the gearbox or is no longer located in the sump

And its splash range, and therefore lubrication of the drive shaft bearings is a challenge.

One solution here is to use continuously lubricated bearings for the drive shaft bearings. Another approach is to install a separate grease or oil lubrication system to continuously or periodically supply grease and/or oil to the drive shaft bearings and the connection between the drive shaft and the motor shaft. However, both of these methods increase maintenance costs because the bearings that are continuously lubricated, as well as the seals and threaded joints of the grease lubrication system, must be periodically inspected and replaced. Thus, operating costs are increased while the effective operating time of the trench wall cutter is correspondingly reduced.

Furthermore, document EP 1637794B 1 proposes that the transmission lubricating oil located in the transmission bottom groove is conveyed upwards by the rotating drive shaft to the drive shaft bearing. For this purpose, the drive shaft is provided with a feed screw which, depending on the type of worm shaft, feeds lubricating oil upwards and lubricates the toothing between the drive shaft and the motor shaft. However, this solution not only has the disadvantage of increasing the production costs of the drive shaft, but also involves, above all, the problem that lubrication of the drive shaft bearings can only be achieved when the drive shaft is operated in the "correct" direction of rotation. If the direction of rotation is reversed, the lubricating oil is conveyed downwards instead. In addition, the transmission lubricating oil only begins to be supplied to the drive shaft when the transmission or the drive shaft is started, which leads to a short-term lack of lubrication of the drive shaft bearings at least at start-up. Here, longer downtime deteriorates the lubrication oil supply, as the lubrication oil settles down.

Disclosure of Invention

It is therefore an object of the present invention to provide an improved drive for a trench wall cutter and an improved trench wall cutter which avoid the disadvantages of the prior art and further develop the prior art in an advantageous manner. In particular, a continuous lubrication of the drive shaft bearing between the hydraulic motor and the transmission will be achieved without increasing maintenance work, which lubrication is functionally independent of the direction of rotation of the drive and no start-up problems arise.

According to the invention, this object is achieved by a drive device according to claim 1 and a trench wall cutter according to claim 17. Preferred embodiments of the invention are the subject of the dependent claims.

It has therefore been proposed not to lubricate the drive shaft bearings, or at least not primarily to lubricate the transmission lubricating oil, but to use hydraulic oil for operating the hydraulic motor for this purpose. According to the invention, the drive shaft bearing has a lubricant inlet which supplies leakage oil from the hydraulic motor and/or hydraulic oil from a hydraulic circuit for operating the hydraulic motor to the drive shaft bearing. Thus, at least a part of the leaked oil of the hydraulic motor and/or a part of the hydraulic oil from the hydraulic circuit is led through the drive shaft bearing to be lubricated and/or other parts of the transmission system between the hydraulic motor and the transmission to be lubricated in order to lubricate the drive shaft bearing or said other parts.

In an advantageous development of the invention, in order to lubricate the drive shaft bearing and/or the connection between the drive shaft and the hydraulic motor, a leakage of the hydraulic motor can be deliberately induced and/or increased, for example by omitting the shaft seal on the hydraulic motor and/or by specially provided leakage holes through the motor housing and/or through the motor shaft, in order to lead the leakage oil to the drive shaft bearing and/or the connection.

Said lubricant inlet of the drive shaft bearing may comprise a leakage collector or a leakage collection inlet which is engaged around and/or below the motor shaft of the hydraulic motor and/or an outlet area where the motor shaft protrudes from the motor housing of the hydraulic motor, such that leakage oil drips or splashes into said leakage collection inlet.

Such a leakage collection inlet can be particularly advantageous if the hydraulic motor is arranged above the drive shaft with its downwardly directed motor shaft facing the drive shaft. The hydraulic motor may be arranged upside down and positioned vertically above the drive shaft, wherein the motor shaft of the hydraulic motor may in particular be arranged coaxially with the drive shaft.

As an alternative or in addition to the leakage supply, the lubricant inlet of the drive shaft bearing may also comprise a new oil inlet which may be connected to a part of the hydraulic circuit upstream of the hydraulic motor in order to use fresh hydraulic oil which has not yet been pressurized or consumed hydraulically and/or thermally by the work to be done in the hydraulic motor for the lubrication of the drive shaft bearing. It can be said that the hydraulic oil that should flow into the hydraulic motor to drive said hydraulic motor can be diverted through this new oil inlet. The leakage oil flowing from the hydraulic motor after the work has been completed is usually hot or pressurized thermally, but the new oil branching off from the hydraulic circuit upstream of the hydraulic motor usually has a significantly lower temperature. Hydraulic oil, which is not itself designed for lubricating drive shaft bearings, can produce better lubrication films at cooler temperatures, resulting in better lubrication performance. Furthermore, the drive shaft bearings can be cooled.

In a development of the invention, the at least one drive shaft bearing may comprise a bearing sleeve or housing in which a coupling sleeve is rotatably mounted, which coupling sleeve non-rotatably connects the drive shaft to the motor shaft of the hydraulic motor. The coupling sleeve and/or the drive shaft may be supported radially and/or axially on the inner circumferential surface of the bearing sleeve by means of a rotary bearing (e.g. a rolling bearing and/or a plain bearing), so that the housing or the bearing sleeve rotatably supports the coupling sleeve accommodated in the bearing sleeve and/or the drive shaft extending into the bearing sleeve.

At the same time, the bearing sleeve and/or the coupling sleeve can assume a lubricating function and/or form part of the lubricant inlet through which hydraulic oil is supplied to lubricate the drive shaft bearing and/or the connection between the drive shaft and the motor shaft.

In particular, the coupling sleeve can be designed to be oil-tight towards the drive shaft, so that the interior space of the coupling sleeve forms an oil collecting space and oil inside the coupling sleeve does not easily flow into the drive shaft. Such a sealing design of the coupling sleeve towards the drive shaft can be achieved, for example, by integrally molding the coupling sleeve onto the drive shaft from a homogeneous material.

However, in order to be able to detach the coupling sleeve from the drive shaft (which considerably simplifies installation and maintenance) but on the other hand still achieve a sealed design, a seal can be provided between the coupling sleeve and the drive shaft in order to seal the interior space of the coupling sleeve with respect to the drive shaft.

Advantageously, the coupling sleeve can surround the motor shaft or the motor stub shaft of the hydraulic motor, which projects from the motor housing, in a cup-like manner, so that leakage oil escaping at the motor stub shaft flows into the coupling sleeve and is collected there, in order to lubricate the connection or the engagement face between the coupling sleeve and the motor shaft or between the coupling sleeve and the drive shaft.

In a development of the invention, the non-rotatable connection between the coupling sleeve and the motor shaft and/or between the coupling sleeve and the drive shaft can be realized by a form-locking connection, for example a spline shaft profile and/or a polygonal profile or an otherwise designed hub connection. The lubricant inlet of the drive shaft bearing may supply hydraulic oil as lubricant, in particular leakage oil from a hydraulic motor, to the engagement face of the non-rotatable connection.

As an alternative or in addition to the use of the coupling sleeve as a lubricant distributor, the above-mentioned bearing sleeve, in which the coupling sleeve is rotatably mounted, can also be used as part of the lubricant inlet for supplying the lubricating element with hydraulic oil. In particular, the bearing sleeve can be connected via one end face to the motor housing of the hydraulic motor and/or enclose a motor shaft projecting therefrom.

Advantageously, the bearing sleeve can be sealed by means of a rotary seal towards the coupling sleeve and/or towards the drive shaft, so that the inner space of the bearing sleeve forms a collecting chamber for the hydraulic oil and/or the hydraulic oil supplied to the inner space of the bearing sleeve does not easily flow towards the drive shaft.

Independently thereof, the bearing sleeve may form a vertically mounted non-rotating part.

The bearing sleeve can collect on the one hand oil spills over the motor shaft or splashes out of the motor shaft. Independently of this, however, the bearing sleeve can also be used to supply hydraulic oil or fresh oil branching off upstream of the hydraulic motor to the drive shaft bearing and/or the connecting element between the drive shaft and the motor shaft.

In an advantageous development of the invention, the new oil inlet, which is connectable to a part of the hydraulic circuit upstream of the hydraulic motor, can open into the interior space of the bearing sleeve, in particular into the space between the bearing sleeve and the coupling sleeve. Advantageously, the new oil inlet can pass through the wall of the bearing sleeve, so that new oil can be supplied to the inner space of the bearing sleeve through the bearing sleeve wall.

The new oil inlet may in particular pass through an edge portion of the bearing sleeve connected to the hydraulic motor, so that the new oil is guided to the inner space of the bearing sleeve in such a way that it is very close to the hydraulic motor.

Advantageously, the leaked oil and/or new oil branching off upstream from the hydraulic motor may be led through substantially the entire length of the bearing sleeve and/or returned after being led through the bearing sleeve to the hydraulic circuit for operating the hydraulic motor.

In particular, the bearing sleeve may have a hydraulic oil outlet, which may be arranged at an end section opposite the hydraulic oil inlet, in particular at an end section opposite the new oil inlet. If the new oil inlet is provided on the edge portion of the bearing sleeve which is fastened to the hydraulic motor in the manner described above, the hydraulic oil outlet can be provided on the opposite edge portion of the bearing sleeve which faces away from the hydraulic motor.

In particular, the bearing sleeve may have a new oil inlet on the upper sleeve portion and a hydraulic oil outlet on the lower bearing sleeve portion.

Advantageously, the lubrication of the rolling bearing and/or the plain bearing can be achieved by the bearing sleeve, while the lubrication for transmitting the torque of the hydraulic motor to the toothing or the engagement face of the drive shaft is advantageously provided by the coupling sleeve.

In a further development of the invention, an oil collection chamber can be provided below the drive shaft bearing and/or below the non-rotatable connection between the motor shaft and the drive shaft in order to collect hydraulic oil which escapes through possible leakage and which has been used to lubricate the drive shaft bearing and/or the non-rotatable connection. Since the oil level in the collecting chamber is an indicator of the tightness, the tightness check is made considerably easier.

Advantageously, the chamber can be associated with a fuel level sensor which detects the level of the hydraulic oil collected in the collection chamber and can output a corresponding fuel level signal.

The collection chamber may have a closable drain in order to be able to drain the oil collected periodically or it may also be checked whether oil has leaked and flowed into the collection chamber. If no oil flows out of the collection chamber when the drain is opened, it can be concluded that there is no leakage.

The collecting chamber can advantageously be sealed towards the transmission or can also be designed to be open. In order to avoid leakage of hydraulic oil into the transmission and thus mixing of hydraulic oil and transmission lubricating oil even in the case of an open design, the collecting chamber may also comprise a riser tube (Steigrohr) through which the drive shaft can extend. Alternatively or additionally, however, the collecting chamber can also be sealed off from the drive shaft and/or toward the transmission by means of a seal.

Drawings

The invention will be explained in more detail below on the basis of preferred exemplary embodiments and the associated figures.

Fig. 1 shows a schematic perspective view of a trench wall cutter according to an advantageous embodiment of the invention.

Fig. 2 shows a perspective view of a drive for the cutting wheel of the trench wall cutter of fig. 1, wherein the drive motor is mounted on an upper portion of the support plate and the transmission housing is arranged at a lower portion of the support plate, to which the cutting wheel of the trench wall cutter of fig. 1 is fastened.

Fig. 3 shows a longitudinal section through the drive for driving the cutting wheel of the trench wall cutter of the above figures, showing the drive shaft between the cutting wheel transmission and the hydraulic motor and the drive shaft bearing between the hydraulic motor and the transmission and the non-rotatable connection between the drive shaft and the hydraulic motor shaft.

Fig. 4 shows an enlarged longitudinal section through the drive shaft bearing and the non-rotatable connection between the drive shaft and the motor shaft.

Detailed Description

As shown in fig. 1, a trench wall cutter 1 may comprise an elongated, vertically arranged cutting frame 2, which may be designed as a lattice truss

And/or may comprise two laterally arranged longitudinal guide profiles. At the lower end section, the cutting frame 2 may comprise at least two cutting wheels 3, which are arranged side by side and may be driven in a rotatable manner about respective horizontal axes of rotation, wherein the axes of rotation of the cutting wheels 3 may extend parallel to each other and/or perpendicular to the flat sides of the cutting frame 2.

The cutting wheels 3 can be driven in opposite directions to one another. The cutting drive 4 may be arranged above the cutting wheel 3 at a lower end section of the cutting frame 2 and comprise one or more drive motors 8, for example in the form of hydraulic motors, which may drive the cutting wheel 3 via a transmission or one or more gear stages (getriebeffe) 9.

As shown in fig. 1, the carrier device 5 can hold the cutting frame 2 with the cutting wheel 3 in a raisable and lowerable manner, or the cutting frame can be suspended thereon. The carrying means 5 are erected on the ground where the corresponding grooves are to be cut and may advantageously be movable. In particular, a cable excavator with an undercarriage (e.g. in the form of a crawler undercarriage 6) may be provided as the carrier 5, wherein the cutting frame 2 may be raised and lowered by means of a boom 7 of the carrier 5.

As shown in fig. 2 to 4, the cutting drive 4 can be arranged on a support plate (lagersthill) 10 or comprise such a support plate 10, by means of which the drive can be fastened to the cutting frame 2. For example, the support plate 10 may be a T-shaped support, the upper part of which may be fastened to the cutting frame 2, while the lower part thereof may carry a drive/transmission housing 11 in which the gear stage 9 is at least partially housed.

The drive motor 8 may, for example, be fastened to an upper end of the support plate 10 and drivingly coupled to the gear stage 9 via a drive shaft 12 which may extend within the support plate 10. The gear stage 9 may comprise one or more planetary gear stages in order to drive one of the cutting wheels 3.

As shown in fig. 3, the two planetary gears 9 for driving the cutting wheel 3 can be drivingly connected via a substantially vertically arranged drive shaft 12 to a hydraulic motor 8, which can be arranged above the transmission 9 on the support plate 10. The motor stub shaft 16 of the hydraulic motor 8, which projects from the motor housing 17, is arranged insertably downwards and preferably coaxially with the drive shaft 12. The motor shaft 16 of the hydraulic motor 8 may be arranged vertically and placed downwards.

As shown in fig. 4, the motor shaft 16 of the hydraulic motor 8 can be connected non-rotatably to the drive shaft 12 by means of a coupling sleeve 21, wherein the coupling sleeve 21 can be mounted on the motor shaft 16 in a cup-shaped manner on the one hand and on the drive shaft 12 in a cup-shaped manner on the other hand. The non-rotatable connection between the coupling sleeve 21 and the motor shaft 16 or between the coupling sleeve 21 and the drive shaft 12 may for example comprise a splined shaft profile, a toothed profile or a polygonal profile.

In this case, the coupling sleeve 21 can advantageously be rotatably supported on the bearing sleeve 20 by means of a rolling bearing 25, alternatively or additionally also by means of a plain bearing, which can surround or accommodate the coupling sleeve 21. The bearing sleeve 20 may be fixedly arranged, in particular mounted on the support plate 10 and connected to or carrying the hydraulic motor 8. In particular, the bearing sleeve 20 may surround the motor shaft 16 and be connected or fastened on the end face to the motor housing 17 of the hydraulic motor 8 for mounting the hydraulic motor 8. The end face of the bearing sleeve 20 may be fastened to the support plate 10.

In order to lubricate the engagement surfaces between the coupling sleeve 21 and the drive shaft 12 or between the coupling sleeve 21 and the motor shaft 16, the inner space of the coupling sleeve 21 may form part of the lubricant inlet 14 in order to lead oil leakage escaping from the hydraulic motor 8 and/or new oil separately supplied to the inner space of the bearing sleeve 20 to said engagement surfaces. In particular, the inner space of the coupling sleeve 21 may form a leakage collecting inlet 18, which may collect and guide oil leakage escaping at the motor shaft 16 or at the interface between the motor shaft 16 and the motor housing 17 to said engagement face. In order to guide sufficient leakage oil into the upwardly open interior of the coupling sleeve 21, a shaft seal, which seals the motor shaft 16 with respect to the motor housing 17, can be omitted from the hydraulic motor 8, so that by omitting the shaft seal, leakage oil escapes at the outlet of the motor shaft 16 and enters the coupling sleeve 21, in particular at the end thereof which is open upwardly and surrounds the motor shaft 16 in a cup-like manner.

To prevent inadvertent spillage of oil leakage at the lower end of the coupling sleeve 21, a seal 22 may be provided at the lower end or lower end section of the coupling sleeve 21 to seal the coupling sleeve 21 relative to the drive shaft 12. In this case, the seal 22 can seal a gap provided circumferentially between the drive shaft 12 and the coupling sleeve 21, in particular in the shaft portion adjoining the non-rotatable profile of the drive shaft 12 or below this non-rotatable connection.

In order to supply both the lubricating point located in the coupling sleeve 21 and the rolling bearing 25 arranged between the coupling sleeve 21 and the bearing sleeve 20 with hydraulic oil, it is also possible to use the leakage oil which escapes from the hydraulic motor 8 and which can be splashed by the rotating motor shaft 16, in particular if the coupling sleeve 21 does not completely close the motor shaft 16 in the manner of the motor housing 17.

Instead of or in addition to said leakage of oil, however, it is also possible to supply new oil into the gap between the bearing sleeve 20 and the coupling sleeve 21, which new oil branches off upstream of the hydraulic motor 8 from the hydraulic circuit 15 for driving the hydraulic motor 8.

Advantageously, the bearing sleeve 20 may comprise a new oil inlet 19, which may extend through the wall of the bearing sleeve 20 at the upper end of the bearing sleeve 20 directly adjacent to the motor housing 17 (see fig. 4). By supplying new oil to the inner space of the bearing sleeve 20 at the upper end section of the bearing sleeve 20, this new oil can flow downward or drip or splash under gravity drive to lubricate the bearing 25.

Advantageously, the lower end section of the bearing sleeve 20 can be sealed off by means of a rotary seal 23 with respect to the drive shaft 12 and/or with respect to the coupling sleeve 21, so that the annular interior space between the bearing sleeve 20 and the coupling sleeve 21 or the drive shaft 12 is sealed off downwards, in order to prevent hydraulic oil from flowing into the transmission 9 and mixing with the transmission oil there.

Advantageously, said seal 22, in particular in the form of a rotary seal for sealing the bearing sleeve 20, can be arranged below all the bearings 25.

As shown in fig. 4, a collection chamber 24, which is formed around the drive shaft 12 or through which the drive shaft 12 passes, can advantageously be provided below the bearing and the

coupling sleeve

20 or 21, in particular below the seal 22 and/or the rotary seal 23. For example, the collection chamber 24 may be formed in the support plate 10. Advantageously, the riser 26 may delimit the collection chamber 24 and extend around the drive shaft 12 or form a rise therein, in order to prevent hydraulic oil collected in the collection chamber 24 from flowing down the drive shaft 12 and into the transmission 9.

Said collection chamber 24 may have a discharge opening 27, which may advantageously be provided with a removable closure 28, so as to be able to open the discharge opening 27. Preferably, the drain 27 is designed such that hydraulic oil that is allowed to be located in the collection chamber 24 can flow out under the drive of gravity. For example, drain 27 may be located at the bottom of collection chamber 24 and may have a slope to allow oil to drain.

By opening the closure 28, it is possible to check whether a leak has occurred at the

seal

22 or 23 and whether there is oil in the collection chamber 24.

Alternatively or additionally, the presence of oil in the collecting chamber 24 can also be checked by means of an oil level sensor system 29, by means of which the filling level in the collecting chamber 24 can be sensed in order to emit a corresponding oil level signal, for example for supply to a machine control system. A maintenance signal may be issued or a maintenance procedure initiated depending on the level of oil filling in the collection chamber 24.

Claims

1. A drive for a trench wall cutter, having a hydraulic motor (8), a transmission (9) which can be connected on the output side to at least one cutting wheel (3) of the trench wall cutter (1), and a drive shaft (12) which connects the hydraulic motor (8) to the transmission (9),

wherein the drive shaft (12) is supported by at least one drive shaft bearing (13) arranged between the hydraulic motor (8) and the transmission (9),

characterized in that the drive shaft bearing (13) has a lubricant inlet (14) which is connected to a leakage outlet of the hydraulic motor (8) and/or a hydraulic circuit (15) for operating the hydraulic motor (8) and is designed to lubricate the drive shaft bearing (13) with a lubricant.

2. The drive arrangement according to the preceding claim, wherein the hydraulic motor (8) is designed such that no shaft seal is present at the outlet of the motor shaft (16) in the motor housing (17), and the lubricant inlet (14) has a leakage collection inlet (18) which is engaged around and/or below the motor shaft (16) and/or around and/or below the outlet of the motor shaft in the motor housing (17).

3. The drive arrangement according to any one of the preceding claims, wherein the hydraulic motor (8) is arranged above the drive shaft (12) with its motor shaft (16) facing downwards towards the drive shaft (12), in particular coaxially aligned with the drive shaft (12) while being vertically inverted.

4. The drive arrangement according to any one of the preceding claims, wherein the lubricant inlet (14) comprises a new oil inlet (19) connected to a part of the hydraulic circuit (15) upstream of the hydraulic motor (8) and designed to lubricate the drive shaft bearing (13) with new hydraulic oil.

5. The drive device according to any one of the preceding claims, wherein the drive shaft bearing (13) comprises a bearing sleeve (20), within which a coupling sleeve (21) is rotatably mounted, the coupling sleeve (21) connecting the drive shaft (12) to the motor shaft (16) in a non-rotatable manner.

6. The drive device according to the preceding claim, wherein a seal (22) is provided for sealing the coupling sleeve (21) with respect to the drive shaft (12), and/or the coupling sleeve (21) is connected to the drive shaft (12) in an oil-tight manner, such that the coupling sleeve (21) forms a hydraulic oil collecting chamber.

7. The drive device according to one of the two preceding claims, wherein one end face of the bearing sleeve (20) is connected to the motor housing (17) of the hydraulic motor (8) and/or the bearing sleeve surrounds a motor shaft (16) of the hydraulic motor (8) which projects from the motor housing.

8. A drive arrangement according to any one of the preceding claims, wherein the fresh oil inlet (19) opens into the interior space of the bearing sleeve (20) and passes through the wall of the bearing sleeve (20).

9. The drive device according to any one of the preceding claims, wherein the bearing sleeve (20) is sealed by means of a rotary seal (23) towards the coupling sleeve (21) and/or towards the drive shaft (12) such that an inner space of the bearing sleeve (20) forms a hydraulic oil collecting chamber.

10. A drive arrangement according to any one of the preceding claims, wherein the bearing sleeve (20) has a hydraulic oil inlet and a hydraulic oil outlet on opposite ends, through which hydraulic oil can wash the bearing sleeve (20).

11. The drive device according to any one of the preceding claims, wherein hydraulic oil passing through the drive shaft bearing (13) is returned into the hydraulic circuit for operating the hydraulic motor (8).

12. The drive arrangement according to any one of the preceding claims, wherein the bearing sleeve (20) forms a hydraulic oil collecting chamber for lubricating a rolling bearing and/or a plain bearing, by which the drive shaft (12) and/or the coupling sleeve (21) is rotatably supported.

13. The drive device according to any one of the preceding claims, wherein the coupling sleeve (21) forms a hydraulic oil collection chamber for lubricating a non-rotatable connection by means of which the drive shaft (12) is non-rotatably connected to a motor shaft (16) of the hydraulic motor (8).

14. The drive device according to any one of the preceding claims, wherein a collection chamber (24) for collecting hydraulic oil is formed below the bearing sleeve (20) and/or the coupling sleeve (21).

15. The drive device according to the preceding claim, wherein the collection chamber (24) is assigned an oil level sensor for detecting the oil level in the collection chamber (24).

16. The drive device according to any one of the two preceding claims, wherein the collection chamber (24) is assigned a drain for draining oil collected in the collection chamber (24), wherein the drain is provided with a removable closure.

17. A trench wall cutter comprising a drive arrangement designed according to any one of the preceding claims.