Motor-gearbox unit, in particular for a tunnel boring machine or for driving a gear ring

Abstract

Motor-gearbox unit, in particular for a tunnel boring machine or for driving a gear ring, comprising: - a housing (10), - an electric motor (20), in particular a synchronous motor, which has a rotor (22) rotatable relative to the housing (10), - a drive shaft (1) coupled to the rotor (22) such that rotation of the rotor (22) causes rotation of the drive shaft (1) relative to the housing (10), - a transmission (80) with at least one planetary stage (50, 60, 70) and an output member (2), wherein the at least one planetary stage (50, 60, 70) couples the drive shaft (1) to the output member (2) in such a way that a rotation of the drive shaft (1), in particular with a reduction in speed, is transmitted to the output member (2), characterized by an overload protection device (30), in particular an overload clutch, wherein the rotor (22) is coupled to the drive shaft (1) or the output member (2) via the overload protection device (30), wherein the electric motor (20) is arranged between the overload protection device (30) and the at least one planetary stage (50, 60, 70).

Description

[0001] The invention relates to a motor-gearbox unit, which is particularly adapted for use in a tunnel boring machine, for driving a boring head of a tunnel boring machine, or for driving a gear ring. Tunnel boring machines have a boring head at the end facing the direction of advance, which is rotated about a boring head rotation axis to extract the material to be mined by the tunnel boring machine.

[0002] Tunnel boring machines are known from the prior art which have a boring head which is rotated about a boring head rotation axis in order to extract the material to be mined by the tunnel boring machine. In order to set the boring head in rotation about its boring head rotation axis, several motor-gearbox units are used in tunnel boring machines. These motor-gearbox units have an electric motor designed as an asynchronous motor which rotates an input shaft of a gearbox. The rotation of the input shaft is transmitted via the gearbox at a reduced speed to a pinion which meshes with a gear ring. The gear ring is connected to the boring head in a rotationally fixed manner, so that rotation of the gear ring causes rotation of the boring head. In the motor-gearbox units from the prior art, it is also known to provide a holding brake which can fix the input shaft of the gearbox with respect to the housing.For this purpose, the holding brake is flanged between the gearbox housing and the motor housing. In the current state of the art, an overload clutch forms the end of the motor-gearbox unit facing away from the output element.

[0003] The components of conventional motor-gearbox units are typically manufactured by multiple suppliers and then assembled together. The motors used in the state-of-the-art for this application are generally heavy and bulky, requiring a lot of installation space. Furthermore, the maximum permissible speeds for the motors in these designs are relatively low to limit heat generation at the rotor bearings and electrical losses.

[0004] US 2004 / 0163409 A1 relates to a drive unit for an electric vehicle, the unit comprising a motor, an inverter and a speed reducer which are integrally supported by a structural component.

[0005] DE 100 29 628 A1 describes a torque transmission device for a motor vehicle with an overload-protected parking lock. The parking lock comprises a multi-disk clutch axially preloaded by a diaphragm spring.

[0006] For example, EP 3 539 813 A1 shows a reduction gear with a multi-stage planetary gear. The multi-stage planetary gears are configured to slow down the rotation of a motor and transmit the slowed rotation to a rotating housing.

[0007] Drives for a gear ring are known per se. For example, DE 10 2009 035 197 A1 discloses a drive unit for driving or braking a gear ring, comprising a motor or brake, a gearbox, and an output shaft on which a pinion is arranged to drive the gear ring. DE 10 2009 035 197 A1 further describes that drive units are used, for example, to drive slewing or swivel gears, in particular to drive a slewing gear of a wind turbine or to drive a slewing or swivel gear of a crane or an excavator. The gear ring has teeth on its outer or inner circumference that mesh with the teeth of the pinion. The gear ring can thus be driven by driving the pinion via the output shaft. Gear rings are also used to drive winches, in particular to drive winches of a crane.

[0008] A device for driving tunnels, galleries or shafts with a shield receiving a drive unit of a rotating drilling tool, which is supported against the wall or against the constructed support in a way that is movable in the direction of advance, and with a drilling tool rotating in front of the shield, which can be moved forward in the direction of advance and retracted into the interior of the shield is known from DE 1 261 813 A.

[0009] The present invention is based on the object of specifying an improved motor-gear unit, in particular for a gear ring drive or for driving a drill head of a tunnel boring machine, wherein in particular the installation space of the motor-gear unit is to be reduced and in particular the efficiency is to be increased.

[0010] The problem is solved by the subject matter of claim 1. Advantageous further developments emerge from the dependent claims, including the independent dependent claims 14 and 15, the description and the figures.

[0011] The invention is based on a motor-gearbox unit, which is designed, for example, as part of a drive for a gear ring and / or a drill head of a tunnel boring machine. However, the motor-gearbox unit can also be used for applications other than those mentioned above. For example, the motor-gearbox unit can be designed and constructed to drive a gear ring of a crane (slewing gear) or to drive a winch.

[0012] The motor-gearbox unit comprises a housing, which can generally be constructed in one piece, but preferably in multiple parts. Furthermore, the motor-gearbox unit comprises an electric motor having a rotor rotatable relative to the housing. The electric motor may further comprise a stator that is rotationally fixed or stationary with respect to the housing. The rotor is rotatable about a rotor rotation axis. For example, the stator may have coils adapted to generate a rotating magnetic field. The rotor may be constantly magnetized, in particular having at least one magnet that is entrained by the rotating field generated by the stator, thereby causing the rotor to rotate about the rotation axis. Alternatively or additionally, the electric motor is a synchronous motor (single-phase or three-phase synchronous machine in motor mode). The synchronous motor is more compact and efficient than the asynchronous motors used for this application.This allows the installation space and weight of the engine-gearbox unit to be reduced.

[0013] The motor-gearbox unit also has a drive shaft coupled to the rotor in such a way that rotation of the rotor causes the drive shaft to rotate relative to the housing. The rotor is coupled to the drive shaft via an overload protection device, for example a component with a predetermined breaking point or an overload clutch, also known as a safety clutch. This means that an overload protection device is arranged kinematically between the drive shaft and the electric motor. The overload protection device (predetermined breaking point, overload clutch, safety clutch) is adapted to separate the electric motor from the drive shaft if the torque acting between the electric motor and the drive shaft exceeds a permissible limit (torque limit). This protects the electric motor and / or the drive train from damage caused by excessively high torques.

[0014] A component with a predetermined breaking point may have a location, such as a notch, a section with a reduced diameter, or the like, where the component breaks—or is generally destroyed—if the limiting torque is exceeded. Since the component is destroyed when the limiting torque is exceeded, it can subsequently be exchanged or replaced.

[0015] The overload clutch can, for example, have a clutch input member and a clutch output member which, as long as the limit torque is not exceeded, are rotationally fixed relative to one another about the axis of rotation. If the limit torque is exceeded, the clutch input member and the clutch output member can be rotated relative to one another about the axis of rotation. A force-locking and / or form-locking connection, in particular with additional components, can be provided between the clutch input member and the clutch output member. These components can be balls and springs, for example. The clutch input member can be connected directly or indirectly to the rotor, for example in a rotationally fixed manner. Rotation of the rotor can cause rotation of the clutch input member. The clutch output member can be connected directly or indirectly, for example by means of a shaft-hub connection, to the drive shaft, in particular in a rotationally fixed manner.The overload clutch can be designed in such a way that - unlike a component with a predetermined breaking point - it separates the rotor from the drive shaft non-destructively. For example, the overload clutch can be designed in such a way that it engages automatically, i.e. connects the rotor to the drive shaft in a rotationally fixed manner, when the torque drops to or below the limit torque. Alternatively, the overload clutch can be designed in such a way that it has to be engaged manually or through further action, i.e. the rotor has to be connected to the drive shaft in a rotationally fixed manner when the torque drops to or below the limit torque. Without further action, the clutch would remain disengaged, even if the torque has dropped to or below the limit torque.

[0016] The motor-gearbox unit further comprises a transmission with at least one planetary stage, for example, a single, two, three, four, five, or even more planetary stages, and an output member. The at least one planetary stage is adapted to couple the drive shaft to the output member in such a way that rotation of the drive shaft, in particular with a reduction in speed, is transmitted to the output member. Transmission of the reduction in speed means that the speed of the rotor of the electric motor is higher than the speed of the output member.

[0017] The output member can, for example, be a shaft, a hub, or a pinion, for example for engagement with a gear ring. The output member designed as a shaft or hub can be adapted for a shaft-hub connection. For example, a shaft can be connected in a rotationally fixed manner to the output member designed as a hub, in particular by means of the shaft-hub connection. Alternatively, a hub can be connected in a rotationally fixed manner to the output member designed as a shaft, in particular by means of the shaft-hub connection. For example, the shaft or hub connected to the output member can be part of a drive train downstream of the motor-gearbox unit. In particular, the shaft or hub connected or connectable to the output member can be connected in a rotationally fixed manner to a pinion (gearwheel).

[0018] The invention further relates to a gear rim drive, in particular for a tunnel boring machine or the slewing ring of a crane, or generally for an application in which a gear rim is to be driven by a motor-gearbox unit. The gear rim drive comprises a gear rim mounted so as to be rotatable about a gear rim rotation axis. The gear rim can be designed as an external gear or as an internal gear. The gear rim drive can have at least one, i.e. a single one or more motor-gearbox units described herein. The rotation axis of the respective motor-gearbox unit can be offset, in particular offset parallel to the gear rim rotation axis. If there are several, for example two, four, eight, twelve or sixteen, motor-gearbox units, these can be distributed around the circumference of the gear rim, in particular evenly or unevenly distributed.For example, designs are possible in which at least one of the motor-gearbox units has a holding brake. In particular, one or more, for example two, of the motor-gearbox units can each have a holding brake, with the remaining motor-gearbox units being designed without a holding brake. Alternatively, gear ring drives are possible in which the motor-gearbox unit has no holding brake or none of the multiple motor-gearbox units has a holding brake. Alternatively, gear ring drives are possible in which the motor-gearbox unit or each of the multiple motor-gearbox units has a holding brake.

[0019] Each motor-gearbox unit can be provided with a pinion that meshes with the toothing of the ring gear and is coupled, in particular in a rotationally fixed manner, to the output member or corresponds to the output member, so that rotation of the output member, in particular about the axis of rotation of its motor-gearbox unit, causes rotation of the ring gear about the ring gear rotation axis. Each motor-gearbox unit can be coupled to the ring gear or, in further embodiments, to a drill head of a tunnel boring machine via the pinion, which meshes with the toothing of the ring gear. The invention further relates to a tunnel boring machine comprising a ring gear drive described herein and a drill head. The ring gear rotation axis can, for example, be arranged in or parallel to the direction of advance of a tunnel boring machine.

[0020] The cutter head is arranged at the end of the tunnel boring machine pointing in the direction of advance of the tunnel boring machine or forms the end pointing in the direction of advance of the tunnel boring machine. The cutter head can be rotated about a cutter head rotation axis to extract the material to be excavated by the tunnel boring machine or is rotated for extraction. The gear ring and the cutter head are coupled in such a way, in particular rotationally fixed or by means of an intermediate gear, that rotation of the gear ring causes rotation of the cutter head about the cutter head rotation axis. For example, the cutter head rotation axis and the gear ring rotation axis can be parallel to one another. In particular, the cutter head rotation axis can be the gear ring rotation axis. The rotation of the cutter head about the cutter head rotation axis or gear ring rotation axis or of the gear ring about the gear ring rotation axis is caused by the rotation of the rotor of the motor-gearbox unit(s).

[0021] The electric motor is arranged between, in particular geometrically between, the overload protection device, in particular the overload clutch, and the at least one planetary stage or the gearbox. This means that the gearbox with the at least one planetary stage is arranged on one end of the electric motor and the overload protection device, in particular the overload clutch, is arranged on the other end of the electric motor. The drive shaft can extend through the rotor, in particular through a passage or a hollow shaft of the rotor. It is generally preferred that the drive shaft rotates about the axis of rotation around which the rotor also rotates. The axis of rotation of the drive shaft corresponds to its central axis. The drive shaft can be mounted on the rotor without torque transmission, so that rotation of the drive shaft relative to the rotor is fundamentally possible. The torque between the rotor and drive shaft is then transmitted via the optionally present overload protection device.If the overload protection device separates the drive shaft from the rotor when the limit torque is exceeded, the drive shaft and rotor can rotate relative to each other around the axis of rotation.

[0022] The drive shaft can protrude from the front of the electric motor, on which the gearbox with at least one planetary gear stage is located. Alternatively or additionally, the drive shaft can protrude from the front of the electric motor, on which the overload protection device or overload clutch is located.

[0023] For example, the overload protection device or clutch can be located on a first side of the electric motor, and the transmission with the at least one planetary stage can be located on a second side of the electric motor. The drive shaft can connect a part of the overload protection device, in particular a clutch output element or a predetermined breaking point, to a part of the at least one planetary stage, for example, a sun gear of the at least one planetary stage, in a rotationally fixed manner. Alternatively, the drive shaft can form the overload protection device, in particular the component with a predetermined breaking point.

[0024] For example, the sun gear driven by the drive shaft can be part of a first planetary stage. The first planetary stage can have a ring gear which is connected in a rotationally fixed manner to the housing, in particular a transmission housing, or is formed by the housing or transmission housing. One or more planet gears can mesh with both the sun gear of the first planetary stage and the ring gear of the first planetary stage. A planet carrier, on which the planet gears are rotatably arranged, can be rotated about the axis of rotation by rotating the sun gear of the first planetary stage. For example, the planet carrier of the first planetary stage can form the output member or be connected in a rotationally fixed manner to the output member, in particular if only a single planetary stage is provided.If there are multiple planetary stages, the planet carrier of the first planetary stage can form a sun gear of a second planetary stage or be connected in a rotationally fixed manner to the sun gear of the second planetary stage. The second planetary stage can have a ring gear which is connected in a rotationally fixed manner to the housing, in particular the transmission housing, or is formed by the housing or transmission housing. One or more planet gears can mesh with the ring gear of the second planetary stage and the sun gear of the second planetary stage. Rotation of the second sun gear about the axis of rotation causes rotation of the second planet carrier about the axis of rotation. The second planet carrier can form the output member or be connected in a rotationally fixed manner to the output member, in particular if two planetary stages are provided.Alternatively, a third planetary stage can be provided, wherein the planet carrier of the second planetary stage forms the sun gear of the third planetary stage or is connected thereto in a rotationally fixed manner. A ring gear of the third planetary stage can be connected in a rotationally fixed manner to the housing, in particular the transmission housing, or can be formed by the housing or transmission housing. One or more planetary gears can mesh with the ring gear of the third planetary stage and the sun gear of the third planetary stage.

[0025] A rotation of the sun gear of the third planetary stage causes the planet carrier of the third planetary stage to rotate around the rotational axis. The planet carrier of the third planetary stage can be connected to the output member in a rotationally fixed manner or form the output member. Alternatively, a fourth planetary stage can be provided, which, like the aforementioned planetary stages, can be connected to the third planetary stage and the output member. The aforementioned connection of multiple planetary stages is merely an example. Other connections of planetary stages or other intermediate gears are also possible.

[0026] The motor-gearbox unit can further comprise a brake, in particular a holding brake, which is adapted to fix the drive shaft in a rotationally fixed manner relative to the housing of the motor-gearbox unit about the rotation axis. The holding brake serves to fix the drive shaft at a standstill or near a standstill relative to the housing in order to block rotation of the drive shaft relative to the housing. Alternatively, the brake can be a service brake or a combined service and holding brake.

[0027] The overload clutch can be arranged between, in particular geometrically between, the brake and the electric motor. This means that the electric motor is arranged on one (first) side of the overload clutch, with the brake arranged on the other (second) side of the overload clutch. In particular, the brake can form the end of the motor-gearbox unit opposite the output member. Such an arrangement of the brake increases the serviceability of the motor-gearbox unit, as both the accessibility of the brake and the accessibility of the safety clutch are simplified. In contrast to designs in which the brake is arranged between the gearbox and the electric motor, in addition to increased serviceability, advantages can also be achieved with regard to the “gearbox - electric motor” interface, as described further below.

[0028] Alternatively or additionally, the electric motor can be arranged between, in particular geometrically between, the brake, which is located on a first side of the electric motor, and the transmission with the at least one planetary stage, which is located on a second side of the electric motor.

[0029] The brake can have at least one first brake body and at least one second brake body. The at least one second brake body can be connected or connectable to the drive shaft in a rotationally fixed manner about the axis of rotation. For example, the at least one second brake body can be held by a second brake body carrier, which is connected to the drive shaft in a rotationally fixed manner, in particular by means of a shaft-hub connection, or engages the drive shaft. For example, in designs with an overload or safety clutch, the second brake body carrier can be separate from the clutch output member or, alternatively, can be mounted on the clutch output member in a rotationally fixed manner or can be formed by the clutch output member.The at least one first brake body can be held in a rotationally fixed manner about the axis of rotation by a first brake body carrier, which is formed by the housing, in particular a brake housing or a clutch housing of the overload or safety clutch, or is rotationally fixedly connected to the housing, in particular the brake housing or the clutch housing. For example, an electromechanically, hydraulically, or pneumatically actuated pressure piece can be provided, which presses the at least one first brake body and the at least one second brake body against one another to create a frictional connection, in particular a static friction connection, between the first and second brake bodies. Alternatively, one or more springs, in particular mechanical springs, can be provided for pressing them against one another, which springs are preloaded such that they press the at least one first brake body and the at least one second brake body against one another.To release the brake, the pressure piece can be moved against the spring force, for example electromechanically, hydraulically or pneumatically, in order to reduce the force with which the first and second brake bodies are pressed against each other, thereby releasing the brake.

[0030] One of the at least one first brake body and the at least one second brake body can be a brake disc or a plurality of brake plates, wherein the other of the at least one first brake body and the at least one second brake body can be one or more brake shoes that can interact with the brake disc, or a plurality of brake plates that can interact with the brake plates that form the at least one first brake body.

[0031] In further developments, a first rolling bearing and a second rolling bearing can be provided, via which the rotor of the electric motor is supported on the housing, in particular an electric motor or motor housing, so as to be rotatable about the axis of rotation. For example, the motor housing can have a first end wall on which the first rolling bearing is supported or on which the first rolling bearing is mounted, and a second end wall on which the second rolling bearing is supported or on which the second rolling bearing is mounted. The first end wall of the motor housing can be formed, for example, by a base of a pot-shaped motor housing or alternatively by a housing cover. Alternatively or additionally, the second end wall of the motor housing can be formed by a base of a pot-shaped motor housing or a housing cover.

[0032] In further developments, the at least one planetary gear stage can be arranged in a receiving space formed by the housing, in particular the transmission housing, wherein the receiving space is connected to at least one of the two rolling bearings in a fluid-communicating manner, in particular by means of lubricant. This advantageously ensures that the rolling bearing, which is fluidly connected to the receiving space, is wetted by the lubricant, in particular the liquid lubricant, for example, the transmission's lubricating oil, thereby lubricating the rolling bearing on the one hand and dissipating heat from the rolling bearing on the other.

[0033] Preferably, the lubrication of the at least one planetary gear stage in the receiving space is implemented as a splash lubrication system. A minimum fill level can be provided for the splash lubrication system, which is designed such that the rolling bearing(s) are wetted in the intended operating position. Preferably, the axis of rotation of the motor-gearbox unit extends substantially horizontally relative to the Earth's gravitational field in the intended operating position.

[0034] The end wall, in particular a housing cover, of the electric motor, on which the rolling bearing, for example the second rolling bearing, is arranged, can have an opening which allows the lubricant to pass from the receiving space of the gear into the rolling bearing.

[0035] For example, the receiving space in which the at least one planetary stage is arranged and a receiving space formed by the housing, in particular the motor housing, in which the rotor is arranged, can be sealed off from one another in a liquid-tight manner. This seal prevents lubricant from the receiving space of the gearbox from getting into the receiving space of the motor. Since the second rolling bearing, which mounts the rotor on the motor housing, for example a housing base or a housing cover, so that it can rotate about the axis of rotation, is preferably wetted by the lubricant from the receiving space of the gearbox and, on the other hand, lubricant should be prevented from getting into the receiving space of the motor, a seal can be provided, in particular a shaft sealing ring or a radial shaft sealing ring, which seals at least one of the first and second rolling bearings off from the receiving space of the motor.This ensures that, on the one hand, the first and / or the second rolling bearing can be wetted with lubricant from the receiving space and, on the other hand, prevents lubricant from penetrating into the receiving space of the motor. For example, an end wall arranged between the gearbox housing and the motor housing, in particular the housing cover, can have an inner circumferential surface which forms a bearing seat for a rolling bearing, in particular the second rolling bearing, in particular for its outer ring. The rotor can have an outer circumferential surface which forms a bearing seat for the rolling bearing, in particular the inner ring of the rolling bearing. This allows the rotor to be supported on the end wall, in particular the housing cover, so as to be rotatable about the axis of rotation.

[0036] Alternatively or additionally, the end wall of the electric motor arranged between the clutch housing and the motor housing, in particular a housing cover, can have an inner circumferential surface that forms a bearing seat for a rolling bearing, in particular the first rolling bearing and / or the outer ring of the rolling bearing. The rotor can have an outer circumferential surface that forms a bearing seat for the rolling bearing, in particular its inner ring. This allows the rotor to be supported on the end wall of the motor housing, in particular the housing cover, so as to be rotatable about the axis of rotation.The end wall, in particular the housing cover, of the motor housing arranged between the electric motor and the gearbox and / or the end wall, in particular the housing cover, of the motor housing arranged between the overload clutch and the motor, can have an inner circumferential surface on which a seal, in particular a shaft seal or radial shaft seal, is seated, which forms a sealing gap with an outer circumferential surface of the rotor. The seal can provide a fluid-tight seal between the first rolling bearing or preferably the second rolling bearing and the receiving space in which the rotor is located. In particular, a seal can be arranged between the second rolling bearing and the receiving space and / or a seal can be arranged between the first rolling bearing and the receiving space.

[0037] In preferred developments, the motor-gearbox unit can have a housing cover between the gear housing, in which the at least one planetary stage is arranged, and the motor housing, in which the rotor is arranged, which forms the end wall, in particular the second end wall of the motor housing. The housing cover can form both a cover for the front end of the gear housing facing the electric motor and a cover for the front end of the motor housing facing the transmission. This means that a common cover is provided for both the gear housing and the motor housing. Compared to conventional solutions in which the gear housing has its own cover and the motor housing its own cover, the present development makes it possible to further shorten the overall length of the motor-gearbox unit and reduce its weight.In addition, the common housing cover allows the second rolling bearing in particular to be lubricated by the gearbox lubricant.

[0038] In further developments in which the at least one planetary stage is arranged in a receiving space formed by the transmission housing, the transmission housing can have one or more grooves or one or more channels, in particular grooves or channels open towards the electric motor, on its end face facing the electric motor, which connect or connect a coolant supply connection formed on the transmission housing in a fluid-communicating manner with a coolant discharge connection, which is also formed on the transmission housing. This means that the coolant, which is guided via the coolant supply connection to the coolant discharge connection, flows through the groove(s) or the channel(s), thereby dissipating heat from the transmission housing and any adjacent components.In particular, the at least one groove or the at least one channel can be closed off from the electric motor by the end wall arranged between the transmission and the electric motor, in particular the end-face housing cover. The end wall or the housing cover thus forms a wall of the fluid channel, which is thereby closed in cross-section and fluidly connects the coolant supply connection to the coolant discharge connection.

[0039] For example, the fluid path leading from the coolant supply port to the coolant discharge port, i.e., the fluid channel formed by the one or more grooves, can be fluidically separated from the receiving space in which the at least one planetary stage is arranged, or sealed from the receiving space. This allows a different fluid, such as water, to be used to cool the transmission and / or the electric motor than the lubricant, such as lubricating oil, which lubricates the at least one planetary stage and, if applicable, the first and / or second rolling bearing.

[0040] Because the end wall of the electric motor closes the groove or grooves pointing towards the electric motor, the end wall, in particular the housing cover of the motor housing, can also be cooled by means of the coolant flowing through the groove or grooves, thereby achieving improved motor cooling.

[0041] The invention has been described using several embodiments and examples. One embodiment of the invention is described below with reference to figures. The features disclosed therein advantageously further develop the subject matter of the invention, individually and in any combination of features. They show: Fig. 1 a sectional view / sketch of a motor-gear unit according to the invention, Fig. 2 a perspective view of a gear drive, in particular of a tunnel boring machine, with a motor-gear unit made of Fig. 1.

[0042] Fig. 2 describes a gear drive, for example for a tunnel boring machine. Fig. 1 shows the engine-gearbox unit from Fig. 2 in a sectional view. The motor-gearbox unit is attached to a machine frame 100, in particular, such that a housing 10 of the motor-gearbox unit is secured to the machine frame in a rotationally fixed manner about the rotational axis D. For example, the housing 10 can be secured to the machine frame 100 by means of screw bolts.

[0043] The gear ring drive further comprises a gear ring 110, which is mounted on a gear ring carrier, for example by means of a roller or plain bearing, for rotation about a gear axis. In the example shown, the gear ring 110 has external teeth. Alternatively, the gear ring can have internal teeth. A pinion 120 engages the gear ring, which has external teeth and engages or meshes with the external teeth of the gear ring or, alternatively, with the internal teeth of the gear ring. A rotation of the pinion 120 thus causes a rotation of the gear ring 110 about the gear ring axis. The pinion 120 is connected to an output member 2 ( Fig. 1) are connected in a rotationally fixed manner. A rotation of the output member 2 causes a rotation of the pinion 120 and thus indirectly also a rotation of the gear ring 110. The gear ring 110 can be connected or coupled in a rotationally fixed manner to a drill head (not shown) of a tunnel boring machine, wherein a rotation of the gear ring 110 about the gear ring rotation axis causes a rotation of the drill head about a drill head rotation axis. As can be seen from the Fig. 1 and Fig. 2, the motor-gear unit comprises an electric motor 20, an overload or safety clutch 30, a brake 40, in particular a holding brake, and a gear 80 with a first planetary stage 50, a second planetary stage 60, a third planetary stage 70 and the output member 2.

[0044] In the example shown, the electric motor 20 is designed as a synchronous machine. The electric motor has a stator 21 with multiple windings around a soft iron core. The stator 21 is adapted to generate a rotating electric field for driving a rotor 22. The rotor 22 has at least one permanent magnet that can be rotated about the axis of rotation D by the rotating electric field of the stator 21. The rotor 22 is supported on a motor housing 25 of the electric motor by means of a first rolling bearing 4 and a second rolling bearing 5, so that it can rotate about the axis of rotation D. The motor housing 25 forms a section of the multi-part housing 10 of the motor-gearbox unit. The motor housing 25 encloses a receiving space 12 in which the rotor 22 and the stator 21 are arranged.

[0045] Due to the compact design of the motor-gearbox unit and the use of a synchronous motor, considerable heat can be generated under certain circumstances, which can be dissipated, for example, through the surface of the motor housing. For this purpose, the motor housing can have cooling fins on its exterior, for example. For example, the motor housing 25 can have a coolant supply connection 29a and a coolant discharge connection 29b. Coolant can be supplied to the electric motor 22 via the coolant supply connection 29a, and coolant can be discharged from the electric motor 20 via the coolant discharge connection 29b. The coolant supply connection 29a and the coolant discharge connection 29b can be connected via at least one coolant channel 29c of the motor housing 25, so that the coolant supplied via the coolant supply connection 29a heats up on its way to the coolant discharge connection 29b and thus dissipates heat from the electric motor 22.The motor housing 25 has a first drum-shaped peripheral wall 27 and a second drum-shaped peripheral wall 26 arranged concentrically therewith. The second peripheral wall 26 circumferentially surrounds the first peripheral wall 27. The peripheral walls 26, 27 extend concentrically around the axis of rotation D. A coolant channel 29c extending helically around the axis of rotation D is formed between the first peripheral wall 27 and the second peripheral wall 26. The coolant channel 29c extends helically around the axis of rotation D from the coolant supply connection 29a, which is arranged on the second peripheral wall 26, to the coolant discharge connection 29b, which is arranged on the second peripheral wall 26. The outer circumference of the first peripheral wall 27 has at least one helical projection running around the axis of rotation D, which abuts the inner circumference of the second peripheral wall 26 and thereby forms the helical channel 29c.The channel 29c serves to conduct a coolant for cooling the electric motor 20, in particular the stator 21, which is in particular thermally conductively connected to the first peripheral wall 27, in particular arranged on the inner circumference of the first peripheral wall 27. On a first end face of the peripheral walls 26, 27, the receiving space 12 enclosed by the peripheral wall 27 is delimited or closed towards an overload clutch 30 by a first end wall formed by a first housing cover 28. Instead of an overload clutch 30, the motor-gearbox unit can have another overload protection device, for example a component with a predetermined breaking point (not shown). The first housing cover 28 has a connecting flange to which a clutch housing 31 is or can be fastened or flanged by means of several screw bolts.To increase the stability of the first housing cover 28, it can optionally have several reinforcing ribs extending upwards towards the connecting flange. The first housing cover 28 is joined to the first peripheral wall 27 and the second peripheral wall 26 by means of several screw bolts.

[0046] The end face of the peripheral walls 26, 27 opposite the first end wall is delimited or closed by a second end wall formed by a second housing cover 7. The second housing cover 7 is joined to the first peripheral wall 27 and / or the second peripheral wall 26 by means of several screw bolts. The second housing cover 28 has a connecting flange that can be connected to a gear housing 81 of the gear 80, in particular by means of several screw bolts. In particular, the gear housing 81 can be flange-mounted to the motor housing 25, in particular to the second housing cover 7, by means of several screw bolts.

[0047] The first housing cover 28 and the second housing cover 7 each have an opening through which a drive shaft 1 extends.

[0048] Additionally, a section of the rotor 22 extends through the passage of the first housing cover 28, forming a passage for the drive shaft 1 and an outer peripheral surface. The outer peripheral surface forms a bearing seat for a first rolling bearing 4, in particular its inner ring. The clutch input member 32 of the clutch 30 is fastened or flanged to the section of the rotor in a rotationally fixed manner, in particular by means of several screw bolts. The clutch input member 32 and the rotor 22 are connected or joined to one another in a rotationally fixed manner about the rotation axis D.

[0049] The housing cover 28 forms an inner circumferential surface, which forms a bearing seat for the rolling bearing 4, in particular its outer ring. The receiving space 12 is sealed with respect to the first rolling bearing 4 by means of a shaft seal 28a, which is arranged on the first housing cover 28 and forms a sealing gap with the rotor 22. Furthermore, the first housing cover 28 has a further sealing element 28b, which also forms a sealing gap with the rotor 22, in particular with the section of the rotor 22 extending through the passage of the housing 28, and seals the first rolling bearing 4 with respect to the overload clutch 30. The first rolling bearing 4 can thus be lubricated, for example by means of grease or oil lubrication, wherein the seals 28a, 28b prevent lubricant from the first rolling bearing 4 from escaping into the receiving space 12 and to the overload clutch 30.

[0050] The second housing cover 7 also has a passage through which a portion of the rotor 22 extends. The portion of the rotor 22 extending through the passage forms an outer peripheral surface, which forms a bearing seat for the second rolling bearing 5, in particular its inner ring. An inner peripheral surface of the second housing cover 7 forms a bearing seat for the rolling bearing 5, in particular its outer ring. Between the portion of the rotor 22 extending into the passage of the second housing cover 7 and an inner peripheral surface of the passage of the second housing cover 7, a gap, in particular an annular gap, is formed, which connects the second rolling bearing 5 in fluid communication with the receiving space 11 enclosed by the transmission housing 81, in which the at least one planetary stage 50, 60, 70 is arranged.This makes it possible for the lubricant, for example from the splash lubrication of the gear 80, to wet the second rolling bearing 5 so that the rolling bearing 5 can be lubricated and heat can also be dissipated from the rolling bearing 5.

[0051] The second housing cover 7 has an inner circumferential surface on which a seal is seated, forming a sealing gap with an outer circumferential surface of the rotor 22, in particular with an outer circumferential surface formed by the section of the rotor 22 extending into the passage of the second housing cover 7. The seal 6 seals the second rolling bearing 5 to the receiving space 12 in a fluid-tight manner. The fill level of the lubricant in the receiving space 11 is selected such that the second rolling bearing 5 is wetted by the lubricant contained in the receiving space 11.

[0052] The housing cover 7 limits or closes the end of the gear box 80 facing the electric motor 20. Furthermore, the second housing cover 7 limits or closes the electric motor 20, which is open toward the gear box 80. The housing cover 7 forms a housing cover for both the motor housing 25 and the gear box housing 81.

[0053] The transmission housing 81 has a first transmission housing part 82 and a second transmission housing part 83 arranged concentrically thereto, which circumferentially surrounds the first transmission housing part 82. The transmission housing parts 82, 83 extend concentrically around the axis of rotation D. A coolant channel extending at least partially around the axis of rotation D is formed between the first transmission housing part 82 and the second transmission housing part 83. The second transmission housing part has a coolant supply connection 90 and a coolant discharge connection 91. The coolant supply connection 90 is fluidly connected to the coolant discharge connection 91 via a coolant channel 92 formed in or by the first transmission housing part 82. Heat is dissipated from the transmission 80 and / or the electric motor 20 via the coolant flowing from the coolant supply connection 90 via the coolant channel 92 to the coolant discharge connection 91.The coolant channel 92 has groove-shaped recesses open toward the electric motor 20 on the end face of the first transmission housing part 82 facing the electric motor 20. The groove-shaped coolant channel sections of the coolant channel and / or the gap(s) between the first transmission housing part 82 and the second transmission housing part 83 are covered toward the electric motor 20 by the second housing cover 7. The second housing cover 7 thus forms a wall of the coolant channel 92. As a result, the coolant flowing through the coolant channel 92 also dissipates heat, in particular, from the second housing cover 7 and therefore from the electric motor 20.

[0054] Between the first housing part 82 and the second housing cover 7, a seal 82a extending annularly around the rotational axis D is arranged, which ensures that the coolant remains fluidly separated from the lubricant in the receiving space 11. Between the second gear housing part 83 and the second housing cover 7, a seal 83a extending annularly over the rotational axis D is arranged, and between the second gear housing part 83 and the first gear housing part 82, a seal 83b extending annularly around the rotational axis D is arranged. The seals 83a and 83b prevent the coolant from escaping into the environment.

[0055] The rotor 22, in particular the section where the second rolling bearing 5 is located, has an inner circumferential surface that forms a gap with the outer circumferential surface of the drive shaft 1. To prevent lubricant from escaping from the receiving space 11, the gap is sealed by a seal 1a extending annularly around the rotational axis D.

[0056] The overload clutch 30 has a clutch output member 33, which is rotationally fixedly connected to the drive shaft 1 via a shaft-hub connection. The overload clutch 30 connects the rotor 22 rotationally fixedly to the drive shaft 1 as long as the transmitted torque does not exceed a torque limit. If the torque limit is exceeded, the overload clutch 30 separates the rotor 22 from the drive shaft 1 by allowing the clutch input member 32 and the clutch output member 33 to rotate relative to each other about the rotation axis D.

[0057] The overload clutch 30 is arranged on the first end face of the electric motor 20, which is opposite the second side, on which the gearbox 80 is arranged. In terms of geometry, the electric motor 20 is arranged between the gearbox 80 and the overload clutch 30. Furthermore, a brake 40, in particular a holding brake, is provided, between which the overload clutch 30 is arranged or enclosed and the electric motor 20. The brake 40 forms the end of the motor-gearbox unit facing away from the output member 2. Because the brake 40—unlike conventional motor-gearbox units—is not enclosed between the electric motor and the gearbox, the brake 40 is easier to access, for example, for servicing. Furthermore, the lubrication and cooling of the second rolling bearing 5 can be easily achieved in this way using the lubricant of the gearbox 80 contained in the receiving space 11.

[0058] The brake 40 is in the Fig.In the example shown in Figure 1, a multi-disk brake is used, which is designed as a holding brake. Alternatively, other brakes can also be provided, such as a disc brake.

[0059] The brake 40 has a second disk carrier 45, which is mounted on the drive shaft 1 in a rotationally fixed manner about the axis of rotation D by means of a shaft-hub connection, here a wedge connection. The brake 40 has a plurality of first disks 41 (first brake bodies), which are connected in a rotationally fixed manner about the axis of rotation D to the brake housing 43 or to a first disk carrier 44, which is connected in a rotationally fixed manner to the brake housing 43. The brake 40 has a plurality of second disks 42 (second brake bodies), which are connected in a rotationally fixed manner about the axis of rotation D to the second disk carrier 45. A second disk 42 is arranged between each two first disks 41, with a first disk 41 being arranged between each two second disks 42. In other words, first and second disks 41, 42 are arranged alternately along the axis of rotation D.The first and second plates 41, 42 can be pressed against each other via a pressure piece 46 of the brake 40, whereby the friction between the plates 41, 42 and thus the braking torque or the holding torque of the brake 40 can be generated or increased. The pressure piece 46 is pressed against the plates 41, 42, for example, by means of one or more preloaded springs 47. The at least one spring 47 is supported on a cover of the brake housing 43 on the one hand and on the pressure piece 46 on the other. The at least one spring thus generates the contact force required for the braking or holding torque on the plates 41, 42. The at least one spring 47 is a helical spring that acts as a compression spring. The pressure piece 46 forms the wall of a pressure chamber (not shown) that can be pressurized with a fluid, in particular pressurized fluid or hydraulic oil, via a channel.The brake housing 43, in particular its cover, has a connection on its outside for connecting a supply line for the pressure chamber. By supplying fluid to the chamber, the pressure piece 46 can be displaced such that, on the one hand, the at least one spring 47 is tensioned and the plates 41, 42 are relieved of the contact pressure of the pressure piece 46, whereby the braking torque of the brake 40 decreases. By discharging fluid from the pressure chamber, in particular by relieving the pressure in the pressure chamber, the at least one spring 47 can press the pressure piece 46 by increasing the contact pressure on the plates 41, 42, whereby the braking or holding torque of the brake 40 increases. By appropriately displacing the pressure piece 46 or by pressurizing the pressure chamber with fluid, the braking torque of the brake 40 can be adjusted almost arbitrarily, i.e. continuously.Continuous adjustment of the braking torque is advantageous if the brake is to be used as a service brake. If the brake 40 is to be used as a holding brake, continuous adjustment of the pressure piece is not absolutely necessary, since the holding brake preferably only needs to be switchable between an open and a closed state. In the open state, the brake is fully open, while in the closed state, the brake is fully closed, i.e., the pressure chamber is relieved of pressure. The brake 40 is preferably designed as a holding brake.

[0060] The braking torque is dissipated via the brake housing 44 or generally via the housing 10 of the motor-gearbox unit, in particular into the machine frame 100. The drive shaft 1 protrudes from a first end face of the motor 20 and is connected, via the projecting portion, in a rotationally fixed manner to the clutch output member 33 and the second disk carrier 45. The drive shaft 1 protrudes from the end face of the electric motor 20 on the second side and is connected, via the projecting portion, in a rotationally fixed manner to a sun gear 51 of the first planetary stage 50. The rotation of the drive shaft 1 causes the sun gear 51 to rotate about the axis of rotation D. The first planetary stage 50, the second planetary stage 60 and the third planetary stage 70 each have a sun gear 51, 61, 71 which can rotate about the axis of rotation D, a ring gear 53, 63, 73 which are fastened to the gear housing 81 in a rotationally fixed manner about the axis of rotation D, and a plurality of planet gears 52, 62, 72 each.The planet gears 52 of the first planetary stage 50 mesh with the ring gear 53 and the sun gear 51 of the first planetary stage 50 and are rotatably arranged on a bearing journal of a planet carrier 54 of the first planetary stage 50. The planet gears 62 of the second planetary stage 60 mesh with the ring gear 63 and the sun gear 61 of the second planetary stage 60 and are rotatably arranged on a bearing journal of a planet carrier 64 of the second planetary stage 60. The planet gears 72 of the third planetary stage 70 mesh with the sun gear 71 and the ring gear 73 of the third planetary stage 70 and are rotatably arranged on a bearing journal of a planet carrier 74 of the third planetary stage 70. The planet carrier 54 is rotationally fixed to the sun gear 61. The planet carrier 64 is rotationally fixed to the sun gear 71. The planet carrier 54 is connected in a rotationally fixed manner to the output member 2 or forms - as shown in this example - the output member 2.The planet carriers 54, 64, 74 are rotatable about the axis of rotation D.

[0061] When the drive shaft 1 and thus also the sun gear 51 are set in rotation about the axis of rotation D by rotation of the rotor 22, the sun gear 51 rolls on the planet gears 52, whereby the planet gear 52 rolls on the ring gear 53. The planet carrier 54 is carried along and rotated about the axis of rotation D. This rotation is transmitted to the sun gear 61. The sun gear 61 rolls on the planet gears 62, which in turn roll on the ring gear 63 and in the process set the planet carrier 64 and the sun gear 71 in rotation about the axis of rotation D. The sun gear 71 rolls on the planet gears 72, which roll on the ring gear 73. The planet carrier 74 is carried along and, together with the output member 2, is set in rotation about the axis of rotation D.

[0062] For example, an external cooling device can be provided, which is connected to the coolant supply port 29a and the coolant discharge port 29b by a first pair of lines. Furthermore, a second pair of lines can be provided, for example, connecting the coolant supply port 90 and the coolant discharge port 91 to the cooling device or to another cooling device. Thus, the cooling circuits of the engine-transmission unit can be operated in parallel.

[0063] Alternatively, a pair of lines can connect the external cooling device to the coolant supply connection 29a and the coolant discharge connection 91, with a further line connecting the coolant discharge connection 29b to the coolant supply connection 90. Alternatively, a pair of lines can be provided that connect the external cooling device to the coolant supply connection 90 and the coolant discharge connection 29b, with a further line being provided that connects the coolant discharge connection 91 to the coolant supply connection 29a. The last two alternatives allow the coolant channels of the engine-gearbox unit to operate in series, i.e., in series. List of reference symbols 1 drive shaft 1a seal 2 output link 3 4 first rolling bearing 5 second rolling bearing 6 Seal, shaft seal 7 second housing cover 10 housings 11 Gearbox mounting space 12 Electric motor housing 13 20 electric motor 21 Stator 22 Rotor 25 engine housing 26 second peripheral wall 27 first peripheral wall 28 first housing cover 28a Seal 28b Seal 29a Coolant supply connection 29b Coolant discharge connection 29c Coolant channel 30 Overload protection, overload clutch, safety clutch 31 Clutch housing 32 clutch input link 33 Clutch output link 40 Brake, holding brake 41 first brake body, discs 42 second brake body, discs 43 Brake housing 44 first slat carrier 45 second slat carrier 46 Pressure piece 47 spring 50 first planetary stage 51 Sun gear 52 Planetary gear 53 ring gear 54 planet carriers 60 second planetary stage 61 Sun gear 62 Planetary gear 63 ring gear 64 planet carriers 70 third planetary stage 71 Sun gear 72 Planetary gear 73 ring gear 74 planet carriers 80 gearboxes 81 Gearbox housing 82 first gearbox housing part 83 second gearbox housing part 82a Seal 83a Seal 83b Seal 90 coolant supply connection 91 Coolant discharge connection 92 Coolant channel / groove 100 machine frame 110 sprocket 120 pinions D axis of rotation

Claims

[1] Motor-gearbox unit, in particular for a tunnel boring machine or for driving a gear ring, comprising: - a housing (10), - an electric motor (20), in particular a synchronous motor, which has a rotor (22) rotatable relative to the housing (10), - a drive shaft (1) coupled to the rotor (22) such that rotation of the rotor (22) causes rotation of the drive shaft (1) relative to the housing (10), - a transmission (80) with at least one planetary stage (50, 60, 70) and an output member (2), wherein the at least one planetary stage (50, 60, 70) couples the drive shaft (1) to the output member (2) in such a way that a rotation of the drive shaft (1), in particular with a reduction in speed, is transmitted to the output member (2), characterized byan overload protection device (30), in particular an overload clutch, wherein the rotor (22) is coupled to the drive shaft (1) or the output member (2) via the overload protection device (30), wherein the electric motor (20) is arranged between the overload protection device (30) and the at least one planetary stage (50, 60, 70). [2] Motor-gearbox unit according to claim 1, characterized by in that the drive shaft (1) extends through the rotor (22) and connects a part of the overload protection device (30), which is located on a first side of the electric motor (20), in a rotationally fixed manner to a part of the at least one planetary stage (50, 60, 70), which is located on a second side of the electric motor (20). [3] Motor-gearbox unit according to claim 1 or 2, characterized by a brake (40), in particular a holding brake, wherein the overload protection device (30) is arranged between the brake (40) and the electric motor (20). [4] Motor-gearbox unit according to one of claims 1 to 3, characterized by a brake (40), in particular a holding brake, wherein the electric motor (20) is arranged between the brake (40), which is located on a first side of the electric motor (20), and the at least one planetary stage (50, 60, 70), which is located on a second side of the electric motor (20). [5] Motor-gearbox unit according to claim 3 or 4, characterized by that the brake (40) has at least one first brake body (41) and at least one second brake body (42) which is or can be connected to the drive shaft (1) in a rotationally fixed manner about the axis of rotation (D), wherein the at least one first brake body (41) and the at least one second brake body (42) can be pressed against one another to achieve a braking effect based on frictional engagement. [6] Motor-gearbox unit according to one of claims 1 to 5, characterized bya first rolling bearing (4) and a second rolling bearing (5), via which the rotor is supported on the housing (10) so as to be rotatable about the axis of rotation (D), wherein the at least one planetary stage (50, 60, 70) is arranged in a receiving space (11) formed by the housing (10) or a gear housing (81), wherein the receiving space (11) is fluidly connected to at least one of the first and second rolling bearings (4, 5). [7] Motor-gearbox unit according to claim 6, characterized by that the receiving space (11), in which the at least one planetary stage (50, 60, 70) is arranged, and a receiving space (12) formed by the housing (10), in particular a motor housing (25), in which the rotor (22) is arranged, are sealed from one another. [8] Engine-gearbox unit according to the preceding claim, characterized bythat a seal (6) is provided which seals at least one of the first and second rolling bearings (4, 5) from the receiving space (12) of the rotor (22). [9] Motor-gearbox unit according to one of claims 1 to 8, characterized by a housing cover (7) arranged between a gear housing (81), in which the at least one planetary stage (50, 60, 70) is arranged, and a motor housing (25), in which the rotor (22) is arranged, which forms both a cover for the front end of the gear housing (81) facing the electric motor (20) and a cover for the front end of the motor housing (25) facing the gear (80). [10] Motor-gearbox unit according to claim 9, characterized byin that the housing cover (7) has an inner circumferential surface which forms a bearing seat for a rolling bearing (5), wherein the rotor (22) has an outer circumferential surface which forms a bearing seat for the rolling bearing (5), whereby the rotor (22) is supported on the housing cover (7) so as to be rotatable about the axis of rotation (D). [11] Engine-gearbox unit according to claim 10, characterized by that the housing cover (7) has an inner circumferential surface on which a seal (6) is seated, which forms a sealing gap with an outer circumferential surface of the rotor (22), wherein the seal (6) seals the rolling bearing (5) in a liquid-tight manner to the receiving space (12) in which the rotor (22) is located. [12] Motor-gearbox unit according to one of claims 1 to 11, characterized byin that the at least one planetary stage (50, 60, 70) is arranged in a receiving space (11) formed by a gear housing (81), wherein the gear housing (81) has one or more grooves (92) on its end face facing the electric motor (20), which grooves connect or connect a coolant supply connection (90) to a coolant discharge connection (91) in a fluid-communicating manner, wherein the groove (92) or the grooves are closed off by a front-side housing cover (7) towards the electric motor (20). [13] Motor-gearbox unit according to claim 12, characterized by that the fluid path leading from the coolant supply connection (90) to the coolant discharge connection (91) is fluidically separated from the receiving space (11) in which the at least one planetary stage (50, 60, 70) is arranged, or is sealed off from the receiving space (11). [14] A gear ring drive comprising at least one motor-gearbox unit according to one of claims 1 to 13, a gear ring (110) mounted rotatably about a gear ring rotation axis (Z), a pinion (120) per motor-gearbox unit which meshes with the toothing of the gear ring (110) and is coupled to the output member (2) so that a rotation of the output member (2) causes a rotation of the gear ring (110). [15] Tunnel boring machine, comprising a gear ring drive according to claim 14 and a drill head at the end pointing in the direction of advance of the tunnel boring machine, wherein the drill head, which is rotated about a drill head rotation axis for excavating the material to be excavated by the tunnel boring machine, and the gear ring (110) are coupled such that rotation of the gear ring (110) causes rotation of the drill head.

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