Electric drive device for a motor vehicle, in particular for a motor vehicle

Abstract

The invention relates to an electric drive device (10) for a motor vehicle, comprising at least a first electric machine (12) having a stator (14) and a rotor (16), comprising a circuit (28) through which a coolant and / or lubricant can flow, in which the stator (14) is arranged, which is to be cooled and / or lubricated by means of the coolant and / or lubricant, and comprising a pump (30) arranged in the circuit (28) and having a first pump connection (PA1) and a second pump connection (PA2), by means of which the coolant and / or lubricant can be conveyed through the circuit (28), wherein, to effect forward travel of the motor vehicle, the rotor (16) is rotatable relative to the stator (14) in a first rotor rotational direction. To effect reverse travel of the motor vehicle, the rotor (16) is rotatable relative to the stator (14) in a second rotor rotational direction opposite to the first rotor rotational direction.The pump (30) can be driven by the rotor (16).

Description

[0001] The invention relates to an electric drive device for a motor vehicle, in particular for a motor vehicle.

[0002] DE 10 2018 130 528 A1 discloses a supply system for applying hydraulic pressure to hydraulic consumers in a drive train of a motor vehicle. The motor vehicle has an electric motor for driving the motor vehicle in the forward and reverse directions, with a main pump being mechanically coupled directly or indirectly to a first motor shaft of the electric motor.

[0003] DE 10 2015 219 503 A1 discloses a drive train for a motor vehicle. The object of the present invention is to create an electric drive system for a motor vehicle that allows for a particularly space-saving and cost-effective supply of a coolant and / or lubricant.

[0004] This object is achieved by an electric drive device having the features of patent claim 1. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0005] The invention also relates to an electric drive device, referred to as an electric drive system, for a motor vehicle, also simply referred to as a vehicle. This means that the motor vehicle, in its fully manufactured state, has the electric drive device and can be driven, in particular purely electrically, by means of the electric drive device. Preferably, the motor vehicle is designed as a motor vehicle, in particular as a passenger car. The electric drive device has at least one electric machine, which is also referred to as the first electric machine. In the context of the present disclosure, ordinals referred to as ordinal numbers such as "first", "first", "first", "second", "second", "second", etc.not necessarily used to indicate or imply a number of elements to which the ordinal numerals refer, but to be able to refer unambiguously to the elements to which the ordinal numerals refer.

[0006] When reference is made above and below to the electrical machine, this shall mean, unless otherwise stated, the first electrical machine. The electrical machine has a stator, which is also referred to as the first stator. The electrical machine also has a rotor, which is also referred to as the first rotor. When reference is made above and below to the stator, this shall mean, unless otherwise stated, the first stator, and when reference is made above and below to the rotor, this shall mean, unless otherwise stated, the first rotor. The electrical drive device also has a circuit through which a preferably liquid coolant and / or lubricant can flow. The circuit is therefore also referred to as a coolant and / or lubricant circuit. The drive device preferably comprises the coolant and / or lubricant.The coolant and / or lubricant is very preferably a liquid. The coolant and / or lubricant is very preferably an oil. The coolant and / or lubricant is also referred to as a fluid or agent, so that whenever the fluid or agent is mentioned above and below, this means the coolant and / or lubricant unless otherwise stated. The stator is arranged in the circuit so that the stator can be supplied with the fluid by means of the circuit or via the circuit. By supplying the stator with the fluid, the stator can be cooled and / or lubricated by means of the fluid. The electric drive device also has a pump arranged in the circuit, which pump is also referred to as the first pump. When the pump is mentioned above and below, this means the first pump unless otherwise stated.The pump has a first pump connection and a second pump connection. In particular, the fluid can flow through the respective pump connection. Very particularly, the pump has a pump housing, also simply referred to as a housing, and a conveying element, which is arranged in particular in the pump housing and is movable, in particular rotatable, relative to the pump housing. By moving, in particular rotating, the conveying element relative to the pump housing, the fluid can be conveyed by means of the conveying element, such that the fluid can be conveyed through the circuit by means of the pump. In particular, the housing has the pump connections. The fluid can thus be conveyed through the circuit by means of the pump.

[0007] To cause the motor vehicle to travel forward, the rotor is rotatable relative to the stator in a first rotor rotational direction. In other words, to drive the motor vehicle forward, the rotor is driven, in particular by means of the stator, such that the rotor is rotated relative to the stator in the first rotor rotational direction. To cause the motor vehicle to travel backward, the rotor is rotatable relative to the stator in a second rotor rotational direction opposite to the first rotor rotational direction. In other words, to drive the motor vehicle backward, the rotor is driven, in particular by means of the stator, such that the rotor is rotated relative to the stator in the second rotor rotational direction opposite to the first rotor rotational direction. The pump can be driven by the rotor, so that the pump is designed as a mechanical pump, i.e. as a mechanically operable pump.Since the pump is driven by the rotor, by rotating the rotor in the first rotor rotation direction, the pump's conveying element can be rotated in a first element rotation direction, particularly relative to the pump housing. In other words, if the rotor is rotated in the first rotor rotation direction relative to the stator, the conveying element is conveyed in the first element rotation direction, particularly relative to the pump housing, by means of the rotor, whereby the fluid is conveyed through the circuit in a first flow direction by means of the conveying element and thus by means of the pump, conveyed away from the pump and the conveying element via the first pump connection, and conveyed to the pump and thus to the conveying element via the second pump connection.This means that when the rotor is rotated in the first rotor rotation direction, the conveying element or the pump conveys the fluid towards itself via the second pump connection, in particular sucks it in, and thus conveys it into the pump or the pump housing, for example, and the conveying element or the pump conveys the fluid away from itself via the first pump connection and thus, for example, out of the pump or the pump housing via the first pump connection.

[0008] By rotating the rotor in the second rotor rotation direction, the conveying element can be rotated in a second element rotation direction opposite to the first element rotation direction, in particular relative to the pump housing. In other words, if the rotor is rotated in the second rotor rotation direction, in particular relative to the stator, the conveying element is thereby rotated in the second element rotation direction, in particular relative to the pump housing, whereby the fluid is conveyed through the circuit in the second flow direction by means of the conveying element, conveyed away from the pump via the second pump connection, and conveyed to the pump via the first pump connection.The conveying element or pump therefore conveys the fluid towards itself via the first pump connection and in particular into the pump housing, so that, for example, the pump or fluid sucks in via the first pump connection and in particular sucks it into the pump housing and thus conveys it in. In addition, the conveying element or pump conveys the fluid away from itself via the second pump connection and in particular out of the pump housing or out of the pump. In other words, if the rotor is rotated in the first rotor direction of rotation, the first pump connection is a high-pressure connection of the pump and is therefore arranged on a high-pressure side of the pump, whereas the second pump connection is a low-pressure connection of the pump and is therefore arranged on a low-pressure side of the pump.The pump or the conveying element conveys the fluid from the low-pressure side to the high-pressure side, so that the pump or the conveying element conveys the fluid towards the pump via the low-pressure side and away from the pump via the high-pressure side. If the rotor is rotated in the second rotor rotation direction, the second pump connection is the high-pressure connection of the pump and is therefore arranged on the high-pressure side of the pump, with the first pump connection being the low-pressure connection of the pump and is therefore arranged on the low-pressure side of the pump. The pump then also conveys the fluid from the low-pressure side to the high-pressure side and thus conveys it towards itself via the low-pressure side and away from itself via the high-pressure side.

[0009] The circuit is designed as a system that is closed to ambient air. Ambient air is understood to mean air that is arranged in the environment of the circuit, in particular of the drive device as a whole. Furthermore, it is provided that a first stator connection of the stator is fluidically connected to the first pump connection, wherein a second stator connection of the stator is fluidically connected to the second pump connection. The fluid can flow through the stator connections. This results in the following: If the rotor is rotated in the first direction of rotation, the first stator connection is supplied with the fluid from the first pump connection, so that the stator is supplied with the fluid via the first stator connection, and the fluid is discharged from the stator via the second stator connection and flows from the second stator connection to the second pump connection.If the rotor is rotated in the second rotor direction of rotation, the second stator connection is supplied with the fluid from the second pump connection, so that the stator is supplied with the fluid via the second stator connection, which is discharged from the stator via the first stator connection and flows from the first stator connection to the first pump connection. This ensures an advantageous supply of the stator with the fluid both when the motor vehicle is traveling forwards and when it is traveling backwards, so that the stator can be advantageously cooled and / or lubricated by means of the fluid both when the motor vehicle is traveling forwards and when it is traveling backwards. The invention thus enables a particularly advantageous supply of the stator both when the motor vehicle is traveling forwards and when it is traveling backwards, and does so with only a small number of parts and thus in a particularly space-saving and cost-effective manner.Compared to conventional solutions, the number of interfaces at which, for example, the fluid is transferred from one element to the other can be kept to a minimum, allowing a particularly compact and cost-effective design of the drive device.

[0010] In order to be able to realize a particularly space-saving and cost-effective design of the drive device, one embodiment of the invention provides that the pump's conveying element is permanently connected to the rotor in a torque-transmitting manner. This means, in particular, that no element for reversing the direction of rotation or changing the direction of rotation of the conveying element is arranged between the rotor and the pump or conveying element, i.e., in a torque path along which a respective torque can be transmitted from the rotor to the pump or conveying element in order to thereby drive the conveying element. This allows the number of parts and thus the installation space requirement, costs, and weight of the drive device to be kept to a particularly low level.

[0011] A further embodiment is characterized in that the pump's delivery element is permanently connected to the rotor in a rotationally fixed manner. This means, in particular, that no element or device for effecting a reversal of the direction of rotation is arranged in the aforementioned torque flow between the rotor and the pump or the delivery element, so that preferably when and whenever the rotor rotates in the first rotor rotation direction, the delivery element rotates in the first element rotation direction, and so preferably when and whenever the rotor rotates in the second rotor rotation direction, the delivery element rotates in the second element rotation direction.Furthermore, the feature that the rotor is permanently connected to the conveying element in a torque-transmitting manner is to be understood as meaning that no switching element is provided which can be switched between a coupling state coupling the rotor and the conveying element to one another in a torque-transmitting manner and a decoupling state in which no torque can be transmitted between the rotor and the conveying element via the switching element.

[0012] In order to be able to realize an advantageous fluid supply in a particularly space-saving and cost-effective manner, a further embodiment of the invention provides that the circuit is free of a filter device for filtering the fluid.

[0013] A further, particularly advantageous embodiment of the invention is characterized by a fluid connection via which a first point of the circuit arranged between the first pump connection and the first stator connection and a second point of the circuit arranged between the second stator connection and the second pump connection can be or are fluidically connected to one another. If the rotor is rotated in the first direction of rotation and thus the conveying element is rotated in the first direction of rotation, whereby the fluid is conveyed through the circuit by means of the conveying element in the first flow direction, the first point is arranged downstream of the first pump connection and upstream of the first stator connection, and the second point is arranged downstream of the second stator connection and upstream of the second pump connection.If the rotor is rotated in the second rotor rotation direction and thus the conveying element is rotated in the second element rotation direction, whereby the fluid is conveyed by means of the conveying element or by means of the pump in the second flow direction and through the circuit, the second location is arranged downstream of the second pump connection and upstream of the second stator connection, and the first location is arranged downstream of the first stator connection and upstream of the first pump connection.

[0014] It has proven particularly advantageous if a shuttle valve and a pressure relief valve, also referred to as the first pressure relief valve, are arranged in the fluid connection. When reference is made above and below to the pressure relief valve, the first pressure relief valve is included below it, unless otherwise stated. This allows for a particularly advantageous fluid supply in a space-saving and cost-effective manner.

[0015] It has also proven particularly advantageous if the shuttle valve has precisely one closure element and two flow cross-sections that can be closed by the closure element, with a connection point for the first pressure relief valve, which is fluidly connected to the first shuttle valve, for example, via the connection point, being arranged between the closable flow cross-sections. This arrangement advantageously enables a protective device for the stators that is independent of the direction of rotation of the pump's delivery element. This allows for a particularly advantageous fluid supply in a space-saving and cost-effective manner.

[0016] In order to keep the costs of the drive device particularly low, a further embodiment of the invention provides that the closure element of the first shuttle valve is designed as a ball.

[0017] In order to be able to realize a particularly advantageous fluid supply in a particularly space- and weight-efficient manner, it has proven particularly advantageous if the electric drive device has a first line element that is fluidically connected to the circuit at a first connection point arranged between the second stator connection and the second pump connection. Preferably, a second line element, acting as a control line, is fluidically connected to the circuit at a second connection point arranged between the first stator connection and the first pump connection.If the rotor is rotated in the first direction of rotation and thus the conveying element in the first conveying element direction, so that the fluid is conveyed through the circuit in the first flow direction, the first connection point is arranged downstream of the second stator connection and upstream of the second pump connection, and thus the second connection point is arranged downstream of the first pump connection and upstream of the first stator connection. Preferably, the second connection point is spaced from the first point. Preferably, the first connection point is spaced from the second point. For example, a third line element is also provided, in which a pressure relief valve, also referred to as a second pressure relief valve, is arranged, which is very preferably provided in addition to the first pressure relief valve. The fluid can flow through the respective line element.A pilot-operated check valve is preferably provided. The pilot-operated check valve can preferably be piloted using the fluid from the control line. The pilot-operated check valve has a first valve connection, a second valve connection, and a third valve connection. The first valve connection is fluidically connected to the first line element, and the second valve connection is fluidically connected to the second line element. The third valve connection is fluidically connected to the third line element. Furthermore, it is preferably provided that a blocking direction of the pilot-operated check valve runs from the first valve connection to the third valve connection.This means that the pilot-operated check valve automatically or automatically, and thus when the pilot-operated check valve is not unlocked, prevents the flow of fluid from the first valve port to the third valve port, so that the flow of fluid from the first valve port to the third valve port and thus in the blocking direction is prevented by means of the pilot-operated check valve. If the pilot-operated check valve is unlocked by the fluid from the control line, the shuttle valve allows the flow of fluid from the first valve port to the second valve port, so that the fluid can flow from the first valve port to the second valve port in the blocking direction. In conjunction with the pressure relief valves used, this leads to fluid being discharged during operation in the first direction of element rotation. This can prevent NVH problems of the mechanically driven pump.Furthermore, this allows a particularly advantageous supply of the fluid to be achieved in a particularly space- and weight-efficient manner.

[0018] In a further embodiment of the invention, in order to achieve a particularly space-saving and cost-effective design of the electric drive device, the electric drive device is provided with a branch valve arranged in the circuit between the first pump connection and the first stator connection, which is thus arranged downstream of the first pump connection and upstream of the first stator connection when the rotor is rotated in the first rotor direction of rotation and thus the conveying element in the first element direction of rotation. The branch valve can be switched between a branching state and a closed state. In the branching state, at least part of the fluid conveyed by the pump can be branched off from the circuit via the branch valve and thus discharged from the circuit.The branched-off fluid can, for example, be supplied to at least one consumer arranged outside the circuit, such as the rotor, so that a particularly advantageous fluid supply can be provided in a particularly simple manner.

[0019] In a further embodiment of the invention, a cooling device for cooling the fluid is arranged in the circuit, whereby a particularly advantageous fluid supply can be provided in a simple manner.

[0020] In a further, particularly advantageous embodiment of the invention, the electric drive device comprises a second electric machine, provided in particular in addition to the first electric machine, which has a second stator arranged in the circuit and connected in parallel fluidically to the first stator, so that, for example, the stators can be supplied with the fluid in parallel via the circuit. Thus, the second stator can also be cooled and / or lubricated by means of the fluid. The invention thus enables a simple, space-saving, and cost-effective supply of the fluid to both stators.

[0021] In particular, the motor vehicle can be driven by means of the second electric machine, in particular purely electrically.

[0022] In a further embodiment of the invention, the electric drive device has a valve device which has a supply connection via which the valve device can be supplied with the fluid pumped by means of a second pump provided in addition to the first pump from outside the circuit. The valve device can be switched between a first switching state and a second switching state. In the first switching state, the fluid supplied to the valve device via the supply connection can be guided to a first inlet point of the circuit arranged between the first pump connection and the first stator connection and can be introduced into the circuit at the first inlet point, wherein the first inlet point is preferably spaced apart from the second connection point and the first point.In the second switching state, the fluid supplied to the valve device via the supply connection can be guided to a second inlet point of the circuit arranged between the second pump connection and the second stator connection and can be introduced into the circuit at a second inlet point, wherein the second inlet point is preferably spaced apart from the second point and the first connection point. A so-called boost function, i.e. a so-called support function, can be implemented by means of the valve device. During or through the support function, the fluid delivered by the second pump is pumped into the circuit as additional fluid at the inlet point, so that the stator can be supplied with both the fluid delivered by the first pump and the fluid delivered by the second pump. The stator can thus be cooled and / or lubricated effectively and efficiently.

[0023] Finally, in a further development of the invention, it has proven particularly advantageous if the second pump is arranged in a conduit arrangement through which the fluid can flow and through which the fluid can be conveyed by the second pump. Preferably, the second pump is an electric pump. The first rotor and a second rotor of the second electric machine are arranged in the conduit arrangement, so that for cooling and / or lubricating the rotors, the rotors can be supplied with the fluid conveyed by the second pump via the conduit arrangement.For example, a parking lock can additionally or alternatively be arranged in the line arrangement, which can be supplied with the fluid delivered by the second pump and with the pressure provided by the second pump, whereby the parking lock can be initiated and / or disengaged. The second pump is particularly advantageously provided to provide a higher pressure and deliver a lower volume flow compared to the first pump. A fluid supply to other elements, in particular transmission elements that require cooling, lubrication, or in particular actuation, can also be integrated into the line arrangement.Particularly advantageously, the second pump and the line arrangement supply fluid to actuating devices of multi-disk clutches or brakes, which require a comparatively high pressure of at least several bar for actuation. However, claw clutches or brakes can also be integrated into the line arrangement, with the second pump then providing a higher pressure than the first pump, which is in particular higher than the maximum pressure permissible for cooling stators in stators. This ensures a particularly energy-efficient supply of fluid.

[0024] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective combinations specified, but also in other combinations or on their own, without departing from the scope of the invention.

[0025] The drawing shows: Fig. 1 is a schematic representation of a first embodiment of an electric drive device for a motor vehicle; Fig. 2 shows a partial schematic representation of a second embodiment of the drive device; and Fig. 3 shows a partial schematic representation of a third embodiment of the drive device.

[0026] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0027] Fig. 1 shows a schematic representation of a first embodiment of an electric drive system 10 for a motor vehicle, which can be driven, in particular purely electrically, by means of the electric drive device 10. The electric drive device 10 has a first electric machine 12, which has a first stator 14 and a first rotor 16. The rotor 16 can be driven by means of the stator 14 and can therefore be rotated about a first machine axis of rotation relative to the stator 14. The drive device 10, which is also referred to as an electric drive system, also has a second electric machine 18, which has a second stator 20 and a second rotor 22. The rotor 22 can be driven by means of the stator 20 and can therefore be rotated about a second machine axis of rotation relative to the stator 20.Via the respective rotor 16, 22, the respective electric machine 12, 18 can provide drive torques for driving the motor vehicle. The drive device 10 also has a transmission 23, via which the motor vehicle can be driven by the electric machines 12 and 18. A first part of the transmission is designated by 24, and a second part of the transmission is designated by 26. In . Fig. 1, regions of the electric drive device 10 are designated B1, B2, and B3, wherein the regions B1, B2, and B3 can be supplied with a preferably liquid and most preferably oil-based coolant and / or lubricant. The coolant and / or lubricant is also referred to as a fluid. By supplying the respective region B1, B2, B3 with the fluid, the respective region B1, B2, B3 can be cooled and / or lubricated by means of the fluid. Fig. 1 is thus that the stators 14 and 20, the rotors 16 and 22 and the gear 23, thus the parts 24 and 26, can be supplied with the fluid, so that the stators 14 and 20, the rotors 16 and 22 and the parts 24 and 26 of the gear 22 can be lubricated and / or cooled by means of the fluid.

[0028] The drive device 10 has a circuit 28 through which the fluid can flow, in which a first pump 30 of the drive device 10 is arranged. By means of the pump 30, the fluid can be conveyed through the circuit 28, either in a first flow direction indicated by an arrow 32 or in a second flow direction indicated by an arrow 34 and opposite to the first flow direction. The pump 30 has a first pump connection PA1 and a second pump connection PA2. If the pump 30 is designed as a mechanically driven pump, it has a conveying element 36 by means of which the fluid can be conveyed through the circuit 28 either in the first flow direction or in the second flow direction. The conveying element 36 is arranged in a pump housing of the pump 30 and is rotatable relative to the pump housing about an element rotation axis.The conveying element 36 can be rotated about the element rotation axis relative to the pump housing selectively in a first element rotation direction or in a second element rotation direction, which is opposite to the first element rotation direction. By rotating the conveying element 36 in the first rotation direction about the element rotation axis and relative to the pump housing, the fluid is conveyed through the circuit 28 in the first flow direction by means of the conveying element 36. By rotating the conveying element 36, which is also referred to as the pump element, in the second rotation direction about the element rotation axis and relative to the pump housing, the fluid is conveyed through the circuit 28 in the second flow direction. As will be explained in more detail below, the pump 30 is a mechanical pump, in particular a purely mechanical pump.

[0029] In order to drive the motor vehicle forward, i.e., to cause the motor vehicle to travel forward, at least one of the rotors 16, 22 is rotated relative to the associated stator 20, 22 in a first rotor rotational direction about the respective machine rotational axis. In order to drive the motor vehicle backward, i.e., to cause the motor vehicle to travel backward in the opposite direction to the forward movement, the at least one rotor 16, 22 is rotated relative to the associated stator 20, 22 in a second rotor rotational direction about the machine rotational axis, opposite to the first rotor rotational direction. In the exemplary embodiment shown in the figures, for example, the at least one rotor 16, 22 is rotor 16.The pump 30, that is to say the conveying element 36, is drivable by the at least one rotor 16, so that by rotating the rotor 16 in the first rotor rotation direction about the first machine rotation axis and relative to the stator 20, the conveying element 36 of the pump 30 is rotatable in the first element rotation direction about the element rotation axis relative to the pump housing, whereby the fluid can be conveyed in the first flow direction through the circuit 28, conveyed away from the pump 30 via the first pump connection PA1 and conveyed towards the pump 30 via the second pump connection PA2.It also follows that by rotating the rotor 16 in the second rotor rotation direction about the first machine rotation axis and relative to the stator 20, the conveying element 36 is rotatable about the element rotation axis relative to the pump housing in the second element rotation direction opposite to the first element rotation direction, whereby the fluid can be conveyed through the circuit 28 in the second flow direction opposite to the first flow direction, can be conveyed away from the pump 30 via the second pump connection PA2 and can be conveyed to the pump 30 via the first pump connection PA1.

[0030] Furthermore, it is provided that the circuit 28 is designed as a system that is closed to ambient air. In addition, the respective stator 14, 20 has a respective first stator connection SA1, which is fluidically connected to the first pump connection PA1. The respective stator 14, 20 also has a respective second stator connection SA2, which is fluidically connected to the second pump connection PA. If the rotor 16 is rotated in the first rotor rotation direction and, as a result, the conveying element 36 is rotated in the first element rotation direction, the pump 30 is thereby operated in a first mode. If the rotor 16 is rotated in the second rotor rotation direction and, as a result, the conveying element 36 is rotated in the second element rotation direction, the pump 30 is operated in a second mode of operation of the pump 30.During the first operation of the pump 30, the stators 14 and 20 are supplied with fluid via the first stator connections SA1, and the fluid is discharged from the stators 14 and 20 via the second stator connections SA2. During the second operation of the pump 30, the stators 14 and 20 are supplied with fluid via the second stator connections SA2, and the fluid is discharged from the stators 14 and 20 via the first stator connections SA1. For example, the impeller 36 of the pump 30 is permanently connected to the rotor 16 in a torque-transmitting manner, in particular permanently connected in a rotationally fixed manner.

[0031] Out of Fig. 1 that the circuit 28 is free of a filter device for filtering the fluid. A fluid connection 38 is provided, via which a first point S1 of the circuit 28, arranged between the first pump connection PA1 and the respective first stator connection SA1, and a second point S2 of the circuit 28, arranged between the second stator connection SA2 and the second pump connection PA2, can be or are fluidically connected to one another. A shuttle valve 40 and a first pressure relief valve 42 are arranged in the fluid connection 38.

[0032] The shuttle valve 40 has precisely one closure element, which is movable relative to an environment of the shuttle valve 40, in particular translationally. The shuttle valve 40 also has two flow cross sections Q1 and Q2 that can be closed by means of the closure element, and a connection point AS to which, for example, the pressure relief valve 42 is connected. The connection point AS is arranged between the flow cross sections Q1 and Q2 that can be closed by means of the closure element, wherein the closure element is designed in particular as a sphere.In this case, the shuttle valve 40 always hydraulically connects the element 42 to the circuit 28 via the point S1 and S2 at which the higher pressure level prevails, which occurs or can occur in particular during the second operation of the pump 30, so that in particular during the second operation of the pump 30, the pressure of the fluid can be limited, in particular, to a maximum value by means of the pressure relief valve 42. In particular during the first operation of the pump 30, the shuttle valve 40 prevents the fluid delivered by the pump 30 in the first operation from flowing from point S1 to point S2; instead, the fluid can flow from point S1 relative to point S2 and the pressure relief valve 42 only to the pressure relief valve 42, so that, for example, in the first operation, the pressure of the fluid can be limited to the maximum value by means of the pressure relief valve 42.Thus, the pressure relief valve 42 can limit the pressure of the fluid to the maximum value both in the first operation and in the second operation, so that a particularly advantageous fluid supply can be achieved in a space-saving, weight-saving and cost-effective manner.

[0033] Fig. 2 shows a second embodiment of the drive device 10. In the second embodiment, the drive device 10 has a first line element L1, a second line element L2, and a third line element L3. The line element L1 is fluidically connected to the circuit 28 at a first connection point V1 arranged between the second stator connection SA2 and the second pump connection PA2. The second line element L2 is a control line which is fluidically connected to the circuit 28 at a second connection point V2 arranged between the first stator connection SA1 and the first pump connection PA1. A second pressure relief valve 50 is arranged in the third line element L3. A pilot-operated check valve 52, also referred to as a second check valve, is provided.The pilot-operated check valve 52 has a first valve port to which the line element L1 is connected, such that the first valve port is fluidically connected to the first line element L1. The pilot-operated check valve 52 has a second valve port to which the second line element L2 is connected, such that the second valve port is fluidically connected to the second line element L2. The pilot-operated check valve 52 has a third valve port to which the line element L3 is connected, such that the third valve port is fluidically connected to the third line element L3. Thus, for example, the third line element L3 is fluidically connected at one end to the third valve port, and at the other end, the third line element L3 opens into a pressure relief valve 50.The pilot-operated check valve 52 can be released by means of the fluid from the control line and has a blocking direction that runs from the first valve connection to the third valve connection. If, for example, a pressure of the fluid acting on the check valve 52 in the line element L2 and thus, for example, at the connection point V2, is less than a threshold value, the check valve 52 is and remains blocked, i.e., closed, whereby the check valve 52 prevents a flow of fluid in the blocking direction through the check valve 52, thus whereby the check valve 52 prevents a flow of fluid from the first valve connection to the third valve connection.However, if the pressure of the fluid in the line element L2 and thus at the connection point V2 increases such that the pressure of the fluid in the line element L2 and thus at the connection point V2 corresponds to the threshold value or is greater than the threshold value, the pilot-operated check valve 52 is thereby unlocked, whereby the check valve 52 releases a flow of fluid in the blocking direction through the check valve 52, so that the fluid can then flow in the blocking direction through the check valve 52 and thus flow from the first valve connection to the third valve connection and subsequently through the line element L3. Any pressure of the coolant and / or lubricant in the line element L3 that is excessive compared to the pressure limit of the valve 50 is then reduced via the valve 50. This can advantageously result in an NVH improvement of the mechanically driven pump.This allows a particularly simple construction of the drive device 10 to be realized.

[0034] Fig. 3 shows a third embodiment of the drive device 10. In the third embodiment, a branch valve 54 is arranged in the circuit 28 between the stator connection SA1 and the pump connection PA1, in particular between the pump connection PA1 and the point S1, and very particularly between the connection point V2 and the point S1. By means of the branch valve 54, at least a portion of the fluid can be branched off from the circuit 28 and thereby discharged from the circuit 28. The branch valve 54 can be switched between a branching state and a closed state. In the branching state, at least the aforementioned portion of the fluid can be branched off from the circuit 28 via the branch valve 54. In the closed state, the fluid is not branched off from the circuit 28 via the branch valve 54.

[0035] Out of Fig. 1 that the drive device 10, for example in the first embodiment, has a valve device 56, which is also referred to as a boost and purge valve. The valve device 56 has a supply connection VA, via which the valve device 56 can be supplied with the fluid conveyed by a second pump 58 of the drive device 10. The pump 58 is an electric pump and is provided in addition to the first pump 30. The valve device 56 can be switched between a first switching state and a second switching state. In the first switching state, the fluid supplied to the valve device 56 via the supply connection VA can be guided to a first inlet point E1 arranged between the first pump connection PA1 and the first stator connection SA1 and can be introduced into the circuit 28 at the first inlet point E1.In the second switching state, the fluid supplied to the valve device 56 via the supply connection VA can be guided to a second inlet point E2 arranged between the second pump connection PA2 and the second stator connection SA2 and can be introduced into the circuit 28 at the second inlet point E2. Furthermore, it is provided that in the first switching state, at least a portion of the fluid can be or is guided from the inlet point E2 via the valve device 56 to a pressure relief valve 60, so that, for example, in particular during the first operation of the pump 30, a pressure of the fluid between the pump connection PA2 and the stator connection SA2 can be limited to a maximum value by means of the pressure relief valve 60. For example, during the first operation of the pump 30, the valve device 56 is in the first switching state.In the second switching state, for example, at least a portion of the fluid can be fed from the first inlet point E1 via the valve device 56 to the pressure relief valve 60, so that, for example, in particular during the second operation of the pump 30, a pressure of the fluid between the pump connection PA1 and the stator connection SA1 can be limited to the maximum value by means of the pressure relief valve 60. In particular, the valve device 56 is in the second switching state when the pump 30 is in its second operation. In a blocked state of the valve device 56, both the inlet point E1 and the inlet point E2 are fluidically separated from both the supply connection VA and the pressure relief valve 60. It can be seen that the second pump 58 is arranged in a line arrangement 66 through which the fluid can flow.The rotors 16 and 22 and the parts 24 and 26 of the gear 23 are arranged in the line arrangement 66, so that the areas B2 and B3, thus the rotors 16 and 22 and the parts 24 and 26, can be flowed through by the fluid via the line arrangement 66.

[0036] In the first embodiment, a heat exchanger 68 is arranged in the circuit 28, by means of which the fluid flowing through the circuit 28 can be tempered, i.e., cooled and / or heated, in particular such that heat can be exchanged between the fluid and an additionally provided tempering medium, in particular different from the fluid, via the heat exchanger 68. Alternatively or additionally, a heat exchanger 70 is arranged in the line arrangement 66, via which heat exchanger, for example, the fluid can be tempered, i.e., cooled and / or heated, in particular such that heat can be exchanged between the fluid and, for example, the medium or another medium via the heat exchanger 70. The second pump 58, designed as an electric pump, can, for example, be operated selectively in a third mode or in a fourth mode.In the third mode of operation, the pump 58 conveys the fluid in a third flow direction through at least part of the line arrangement 66, and in the fourth mode of operation, the pump 58 conveys the fluid in a fourth flow at least through the part of the line arrangement 66, wherein the fourth flow is opposite to the third flow direction. The line arrangement 66 can, for example, be used to control a parking lock P, by means of which the motor vehicle can be secured against unwanted rolling away. In order to secure the motor vehicle against unwanted rolling away by means of the parking lock P, the parking lock P is engaged, i.e. activated; in order to allow the motor vehicle to roll, the parking lock P is disengaged, i.e. deactivated. In order to engage the parking lock P, for example, the pump 58 is operated in the third mode or the fourth mode.For example, to disengage the parking lock P, the pump 58 is operated in the fourth mode or the third mode. In particular, in the third mode, the rotors 16 and 22 and the parts 24 and 26 can be supplied with the fluid via respective valves 72a-c arranged in the line arrangement 66, in particular, for example, in such a way that the rotors 16 and 22 are supplied with the fluid while the parts 24 and 26 are not supplied with the fluid and / or in such a way that the parts 24 and 26 are supplied with the fluid while the rotors 16 and 22 are not supplied with the fluid and / or in such a way that the rotors 16 and 22 and the parts 24 and 26 are supplied with the fluid at the same time.In particular, the valve device 56 or the supply connection VA can be supplied with the fluid delivered by the second pump 58 via the valve 72b, wherein this occurs in particular during the third operation of the pump 58. In particular, it is possible to supply the supply connection VA with the fluid while omitting the supply of the rotors 16 and 22 and / or the supply of the parts 24 and 26 with the fluid. Furthermore, it is conceivable to supply the supply connection VA and the rotors 16 and 22 with the fluid simultaneously.

[0037] In particular from Fig. 1 that the drive device 10 is characterized by the particularly completely closed circuit 28, which is very particularly a completely closed oil circuit. In this oil circuit, the fluid, which in the present case is designed as cooling oil, can be pumped in a circle by means of the pump 30, whereby the high-pressure and low-pressure sides of the pump 30 are formed depending on the direction of rotation of the conveying element 36. For example, by means of the pressure relief valve 42 and / or the pressure relief valve 60, the pressure of the fluid on the respective high-pressure side can be limited to the maximum value. If the direction of rotation of the pump 30 is reversed, the pressure conditions are reversed, so that the side that is the high-pressure side in the first operation is the low-pressure side in the second operation, and so that the side that is the low-pressure side in the first operation is the high-pressure side in the second operation.The drive device 10, in particular through the use of the shuttle valve 40, enables the high-pressure side to always be connected to the pressure relief valve, in particular 42, both in the first mode and in the second mode. The valve device 56 has a similar function. This can ensure that the low-pressure side is always connected to the second pressure relief valve 60, whereby the pressure on the low-pressure side is limited to the maximum value when the additional fluid is introduced into the circuit 28 at the respective inlet point E1, E2. If the valve device 56 is in the first switching state or in the second switching state, a boost state, also referred to as the support state, is thereby set.In this boost state, the fluid is conveyed, in particular pumped, from the line arrangement 66, which is designed, for example, as a second hydraulic circuit, into the circuit 28 in order to achieve a particularly high volume flow of the fluid in the circuit 28. For this purpose, the additional fluid from the line arrangement 66 is introduced into the circuit 28 via the valve device 56, optionally at the inlet point E1 or E2.

[0038] At least the following advantages can be realized: - high system efficiency because: Pressure resistances in the main flow of circuit 28 result only from the stator, cooler and line (no valve or filter); - due to the filter-free closed circuit of circuit 28, it does not have to be designed for high volume flows, thus reducing costs; - Pressure requirements from rotor cooling, gear lubrication, and P-controls are separated from volume flow requirements (e.g., stator) of circuit 28. This concept reduces power losses. - Pressure-sensitive components such as stators or coolers are decoupled from actuators that require an increased pressure level for switching or can cause pressure pulses in the system. - In the case of a mechanically driven pump, no complex Graetz circuit is required to protect pumps and the system. - Improvement of the NVH behavior of pump 30, especially at high requested cooling volume flows.

[0039] In the second embodiment, for example, the valve device 56, which is omitted, is replaced by the line elements L1, L2, and L3 and the check valve 52, wherein, for example, the pressure relief valve 50 can be the pressure relief valve 60 of the first embodiment. This can simplify the system. However, this can result in the boost state only being possible, advantageous, or permissible in one of the rotational directions of the pump 30, and in this case, for example, in the first operation, thus in the first element rotational direction. Fig.2, the boost state is, for example, only permissible during the first operation of the pump 30. From a certain pressure, which is built up by the additional fluid and prevails on the high-pressure side, the check valve 52 is unlocked, thereby releasing the pressure relief valve 50 on the low-pressure side, in particular for a flow from the connection point V1 to the pressure relief valve 50.

[0040] In the fifth embodiment, the heat exchanger 68 is provided in particular as a particularly powerful heat exchanger, more particularly as a particularly powerful cooler. To supply additional consumers, such as the rotors 16 and 22 and / or at least a third rotor of a third electric machine, with the fluid, the branch valve 54, for example, is used, via which the fluid branched from the circuit 28 can be supplied to the respective consumer.

Claims

[1] An electric drive device (10) for a motor vehicle, comprising at least one first electric machine (12) having a stator (14) and a rotor (16), a circuit (28) through which a coolant and / or lubricant can flow, in which the stator (14) is arranged, which is to be cooled and / or lubricated by means of the coolant and / or lubricant, and a pump (30) arranged in the circuit (28) and having a first pump connection (PA1) and a second pump connection (PA2), by means of which the coolant and / or lubricant can be conveyed through the circuit (28), wherein: - to effect forward travel of the motor vehicle, the rotor (16) is rotatable relative to the stator (14) in a first rotor rotation direction; - in order to cause the motor vehicle to travel backwards, the rotor (16) is rotatable relative to the stator (14) in a second rotor rotation direction opposite to the first rotor rotation direction; - the pump (30) is driven by the rotor (16) so that: ◯ by rotating the rotor (16) in the first rotor rotation direction, a conveying element (36) of the pump (30) can be rotated in a first element rotation direction, whereby the coolant and / or lubricant can be conveyed through the circuit (28) in a first flow direction (32), conveyed away from the pump (30) via the first pump connection (PA1) and conveyed to the pump (30) via the second pump connection (PA2); and ◯ by rotating the rotor (16) in the second rotor rotation direction, the conveying element (36) can be rotated in a second element rotation direction opposite to the first element rotation direction, whereby the coolant and / or lubricant can be conveyed through the circuit (28) in a second flow direction (34) opposite to the first flow direction (32), can be conveyed away from the pump (30) via the second pump connection (PA2) and can be conveyed to the pump (30) via the first pump connection (PA1); - the circuit (28) is designed as a system closed to ambient air; - a first stator connection (SA1) of the stator (14) is fluidically connected to the first pump connection (PA1); and - a second stator connection (SA2) of the stator (14) is fluidically connected to the second pump connection (PA2). [2] Electric drive device (10) according to claim 1, characterized bythat the conveying element (36) of the pump (30) is permanently connected to the rotor (16) in a torque-transmitting manner. [3] Electric drive device (10) according to claim 1 or 2, characterized by that the conveying element (36) of the pump (30) is permanently connected to the rotor (16) in a rotationally fixed manner. [4] Electric drive device (10) according to one of the preceding claims, characterized by that the circuit (28) is free of a filter device for filtering the coolant and / or lubricant. [5] Electric drive device (10) according to one of the preceding claims, characterized by a fluid connection (38) via which a first point (S1) of the circuit (28) arranged between the first pump connection (PA1) and the first stator connection (SA1) and a second point (S2) of the circuit (28) arranged between the second stator connection (SA2) and the second pump connection (PA2) can be or are connected to one another in a fluidic manner. [6] Electric drive device (10) according to claim 5, characterized by that a shuttle valve (40) and a pressure relief valve (42) are arranged in the fluid connection (38). [7] Electric drive device (10) according to claim 6, characterized by that the shuttle valve (40) has exactly one closure element and two flow cross-sections (Q1, Q2) that can be closed by the closure element, wherein a connection point (AS) for the pressure relief valve (42) is arranged between the closable flow cross-sections (Q1, Q2). [8] Electric drive device (10) according to claim 6 or 7, characterized by that the closure element (44) of the shuttle valve (40) is designed as a ball. [9] Electric drive device (10) according to one of the preceding claims, characterized by : - a first line element (L1) which is fluidically connected to the circuit (28) at a first connection point (V1) arranged between the second stator connection (SA2) and the second pump connection (PA2); - a second line element (L2) as a control line, which is fluidically connected to the circuit (28) at a second connection point (V2) arranged between the first stator connection (SA1) and the first pump connection (PA1); - a third line element (L3) in which a pressure relief valve (50) is arranged; and - a check valve (53) which can be unlocked by means of the coolant and / or lubricant from the control line and which has: ◯ a first valve port fluidly connected to the first line element (L1); ◯ a second valve port which is fluidically connected to the second line element (L2); and ◯ a third valve port which is fluidically connected to the third line element (L3), wherein a blocking direction of the pilot-operated check valve (52) extends from the first valve port to the third valve port. [10] Electric drive device (10) according to one of the preceding claims, characterized by a branch valve (54) arranged in the circuit (28) between the first pump connection (PA1) and the first stator connection (SA1), which can be switched between: - a branching state in which at least a portion of the coolant and / or lubricant can be branched off from the circuit (28) via the branching valve (54) and thus discharged; and - a closed state in which branching of the coolant and / or lubricant from the circuit (28) via the branch valve (54) is prevented. [11] Electric drive device (10) according to one of the preceding claims, characterized bya cooling device (68) arranged in the circuit (28) for cooling the coolant and / or lubricant. [12] Electric drive device (10) according to one of the preceding claims, characterized by a second electric machine (18) having a second stator (20) arranged in the circuit (28) and connected in parallel to the first stator (14). [13] Electric drive device (10) according to one of the preceding claims, characterized by a valve device (56) which: - has a supply connection (VA) via which the valve device (56) can be supplied with the coolant and / or lubricant conveyed by means of a second pump (58) from outside the circuit (28); and - can be switched between: ◯ a first switching state in which the coolant and / or lubricant supplied to the valve device (56) via the supply connection (VA) can be guided to a first inlet point (E1) of the circuit (28) arranged between the first pump connection (PA1) and the first stator connection (SA1) and can be introduced into the circuit (28) at the first inlet point (E1); and ◯ a second switching state in which the coolant and / or lubricant supplied to the valve device (56) via the supply connection (VA) can be guided to a second inlet point (E2) of the circuit (28) arranged between the second pump connection (PA2) and the second stator connection (SA2) and can be introduced into the circuit (28) at the second inlet point (E2). [14] Electric drive device (10) according to claims 12 and 13, characterized by , that: - the second pump (58) is arranged in a line arrangement (66) through which the coolant and / or lubricant can flow, through which the coolant and / or lubricant can be conveyed by means of the second pump (58); - the rotor (16) as the first rotor (16) and a second rotor (22) of the second electrical machine (18) are arranged in the line arrangement (66) and can thereby be supplied with the coolant and / or lubricant conveyed by means of the second pump (58) via the line arrangement (66) for cooling and / or lubricating the rotors (16, 22); - the second pump (58) is an electric pump; - a parking lock (P) is arranged in the line arrangement (66), which can be supplied with the coolant and / or lubricant delivered by the second pump (58), whereby the parking lock (P) can be engaged and / or disengaged; and - a transmission (23) is arranged in the line arrangement (66), via which transmission the motor vehicle can be driven by means of the electrical machines (12, 18), wherein for cooling and / or lubricating and / or actuating switching elements of the transmission (23), the transmission (23) can be supplied via the line arrangement (66) with the coolant and / or lubricant conveyed by means of the second pump (58).

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