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

The invention relates to an electric drive device for a motor vehicle, in particular for a motor vehicle.DE 10 2015 219 503 A1 discloses a drive train for a motor vehicle as known. It is the object of the present invention to provide an electric drive device for a motor vehicle, so that a particularly space-saving and cost-effective supply with a coolant and / or lubricant can be realized.This object is achieved by an electric drive device having the features of claim 1. Advantageous embodiments with expedient developments of the invention are specified in the other claims.The invention also relates to an electric drive device, referred to as an electric drive system, for a motor vehicle, also referred to simply as a vehicle. This means that the motor vehicle has the electric drive device in its completely produced state and can be driven electrically, in particular purely, by means of the electric drive device. The motor vehicle is preferably 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 a first electric machine. Within the scope of the present disclosure, ordinals referred to as ordinal words such as "first", "first", "first", "second", "second", "second", etc. are also not necessarily used to indicate or imply a number of elements to which the ordinal words relate, but rather to be able to unambiguously refer to the elements to which the ordinal words relate.If the reference is made above and below to the electric machine, this is to be understood as meaning the first electric machine, unless otherwise stated.The electric machine has a stator, which is also referred to as a first stator. The electric machine also has a rotor, which is also referred to as the first rotor. If the reference is to the stator above and below, this should be understood to mean the first stator unless otherwise stated, and if the reference is to the rotor above and below, this should be understood to mean the first rotor unless otherwise stated. The electric drive device also has a circuit through which a preferably liquid coolant and / or lubricant can flow. Therefore, the circuit is also referred to as a cooling and / or lubricant circuit. The drive device preferably comprises the coolant and / or lubricant. Most preferably, the coolant and / or lubricant is a liquid. Most preferably, the coolant and / or lubricant is an oil. The coolant and / or lubricant is also referred to as a fluid or agent, so that when the fluid or agents are mentioned above and below, unless otherwise stated, this is to be understood as the coolant and / or lubricant. 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 is also referred to as a first pump. If the pump is mentioned above and below, this is to be understood as meaning 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. In particular, the pump has a pump housing, also referred to simply as a housing, and a delivery 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 delivery element relative to the pump housing, the fluid can be delivered by means of the delivery element, so that the fluid can be delivered 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.To effect forward travel of the motor vehicle, the rotor is rotatable relative to the stator in a first rotor rotational direction. In other words, in order to drive the motor vehicle forwards, the rotor is driven, in particular by means of the stator, in such a way that the rotor is rotated relative to the stator in the first rotor rotational direction. To effect a rearward travel of the motor vehicle, the rotor is rotatable relative to the stator in a second rotor rotational direction opposite the first rotor rotational direction. In other words, in order to drive the motor vehicle backward, the rotor is driven, in particular by means of the stator, in such a way that the rotor is rotated relative to the stator in the second rotor rotational direction opposite 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 can be driven by the rotor, by rotating the rotor in the first rotor rotational direction, the delivery element of the pump is rotatable in a first element rotational direction, in particular relative to the pump housing. In other words, if the rotor is rotated in the first direction of rotation of the rotor relative to the stator, the delivery element is hereby delivered by means of the rotor in the first direction of rotation of the element, in particular relative to the pump housing, as a result of which the fluid is delivered through the circuit in a first direction of flow by means of the delivery element and thus by means of the pump, is delivered away from the pump and from the delivery element by means of the first pump connection and is delivered towards the pump and thus towards the delivery element by means of the second pump connection. This means that when the rotor is rotated in the first rotor rotational direction, the delivery element or the pump delivers the fluid to itself via the second pump connection, in particular draws it, and thus delivers it, for example, into the pump or the pump housing, and the delivery element or the pump delivers the fluid away from itself via the first pump connection and thus, for example, out of the pump or out of the pump housing via the first pump connection.By rotating the rotor in the second rotor rotational direction, the delivery element is rotatable in a second element rotational direction opposite the first element rotational direction, in particular relative to the pump housing. In other words, if the rotor is rotated in the second rotor rotational direction, in particular relative to the stator, the delivery element is thereby rotated in the second element rotational direction, in particular relative to the pump housing, as a result of which the fluid is delivered through the circuit in the second flow direction by means of the delivery element, is delivered away from the pump via the second pump connection and is delivered towards the pump via the first pump connection. Thus, the delivery element or the pump delivers the fluid via the first pump connection toward it and in particular into the pump housing, so that, for example, the pump or the fluid draws in via the first pump connection and in particular draws in into the pump housing and thus delivers it. In addition, the delivery element or the pump thus delivers the fluid away from itself via the second pump connection and in the process in particular out of the pump housing or out of the pump. In other words, if the rotor is rotated in the first rotor rotational direction, the first pump connection is a high-pressure connection of the pump and thus arranged on a high-pressure side of the pump, wherein the second pump connection is a low-pressure connection of the pump and thus arranged on a low-pressure side of the pump. In this case, the pump or the conveying element conveys the fluid from the low-pressure side to the high-pressure side, with the result that the pump or the conveying element conveys the fluid via the low-pressure side toward the pump and conveys it away from the pump via the high-pressure side. If the rotor is rotated in the second rotor rotational direction, the second pump connection is the high-pressure connection of the pump and thus arranged on the high-pressure side of the pump, wherein the first pump connection is the low-pressure connection of the pump and thus arranged on the low-pressure side of the pump, wherein the pump also then delivers the fluid from the low-pressure side to the high-pressure side and thus delivers it towards it via the low-pressure side and delivers it away from it via the high-pressure side.The circuit is designed as a system closed with respect to ambient air. Ambient air is understood to mean air which is arranged in an environment of the circuit, in particular of the drive device as a whole. In addition, 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. The following now results from this: 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 rotational direction, the second stator connection is supplied with the fluid from the second pump connection, so that the stator is supplied via the second stator connection with the fluid, which is discharged from the stator via the first stator connection and flows from the first stator connection to the first pump connection. This makes it possible to ensure advantageous supply of the stator with the fluid both during forward travel and during reverse travel of the motor vehicle, with the result that the stator can be advantageously cooled and / or lubricated by means of the fluid both during forward travel and during reverse travel of the motor vehicle. The invention thus enables a particularly advantageous supply of the stator both during forward travel and during reverse travel and that with only a small number of parts and thus in a particularly space- and cost-effective manner. In comparison with conventional solutions, a number of interfaces at which, for example, the fluid is transferred from one element to the other element can be kept low, so that a particularly compact and cost-effective design of the drive device can be represented.In order to be able to realize a particularly space-saving and cost-effective construction of the drive device, it is provided in one embodiment of the invention that the delivery element of the pump is permanently connected to the rotor in a torque-transmitting manner. This is to be understood in particular as meaning that no element for reversal of the direction of rotation or for changing the direction of rotation of the delivery element is arranged between the rotor and the pump or the delivery element, that is to say in a torque path along which a respective torque can be transmitted from the rotor to the pump or the delivery element in order thereby to drive the delivery element. As a result, the number of parts and thus the installation space requirement, the costs and the weight of the drive device can be kept within a particularly small scope.A further embodiment is characterized in that the delivery element of the pump is permanently connected to the rotor in a rotationally fixed manner. This is to be understood in particular to mean that no element or no device for causing 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 then and whenever the rotor rotates in the first rotor direction of rotation the delivery element rotates in the first element direction of rotation and so that preferably then and whenever the rotor rotates in the second rotor direction of rotation the delivery element rotates in the second element direction of rotation. In addition, the feature that the rotor is permanently connected to the conveying element in a torque-transmitting manner is understood to mean 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 torques can be transmitted between the rotor and the conveying element via the switching element.In order to be able to realize an advantageous fluid supply in a particularly space-efficient and cost-effective manner, it is provided in a further embodiment of the invention that the circuit is free of a filter device for filtering the fluid.A further, particularly advantageous embodiment of the invention is distinguished 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 connected fluidically to one another. If the rotor is rotated in the first rotational direction and thus the delivery element is rotated in the first element rotational direction, whereby the fluid is delivered through the circuit in the first flow direction by means of the delivery element, the first location is arranged downstream of the first pump connection and upstream of the first stator connection and the second location is arranged downstream of the second stator connection and upstream of the second pump connection. If the rotor is rotated in the second rotor rotational direction and thus the delivery element is rotated in the second element rotational direction, as a result of which the fluid is delivered by means of the delivery 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.It has been shown to be particularly advantageous if a shuttle valve and a pressure limiting valve also referred to as a first pressure limiting valve are arranged in the fluid connection. If the pressure limiting valve is mentioned above and below, the first pressure limiting valve is provided below, unless otherwise stated. Thus, a particularly advantageous fluid supply can be provided in a construction space- and cost-effective manner.It has furthermore been found to be particularly advantageous if the shuttle valve has exactly one closure element and two flow cross sections which can be closed by the closure element, wherein a connection point for the first pressure limiting valve, which is connected fluidically to the first shuttle valve, for example, at the connection point, is arranged between the closable flow cross sections. This arrangement advantageously enables a protection device for the stators which is independent of a direction of rotation of the delivery element of the pump. As a result, a particularly advantageous fluid supply can be produced in a construction space- and cost-effective manner.In order to be able to keep the costs of the drive device within a particularly low scope, it is provided in a further embodiment of the invention that the closure element of the first shuttle valve is designed as a ball.In order to be able to realize a particularly advantageous fluid supply in a manner which is particularly advantageous in terms of installation space and weight, it has been shown to be particularly advantageous if the electrical drive device has a first line element which is fluidically connected to the circuit at a first connection point arranged between the second stator connection and the second pump connection. In this case, a second line element as a control line is preferably 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 delivery element is rotated in the first delivery element direction, so that the fluid is delivered 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 apart from the first point. Preferably, the first connection point is spaced apart from the second point. In this case, for example, a third line element is also provided, in which a pressure limiting valve, also referred to as a second pressure limiting valve, is arranged, which pressure limiting valve is provided very preferably in addition to the first pressure limiting valve. The fluid can flow through the respective line element. In this case, an unlockable check valve is preferably provided. Preferably, the unlockable check valve can be unlocked from the control line by means of the fluid. The unlockable 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. In addition, it is preferably provided that a blocking direction of the unlockable check valve runs from the first valve connection to the third valve connection. This means that the unlockable check valve prevents a flow of the fluid from the first valve connection to the third valve connection independently or automatically and thus, when the unlockable check valve is not unlocked, so that a flow of the fluid from the first valve connection to the third valve connection and thus in the blocking direction is prevented by means of the unlockable check valve. If the unlockable check valve is unlocked by means of the fluid from the control line, the shuttle valve allows a flow of the fluid from the first valve connection to the second valve connection, so that the fluid can flow from the first valve connection to the second valve connection in the blocking direction. This, in conjunction with the pressure limiting valves used, leads to a fluid discharge during operation in the first element rotational direction. This makes it possible to avoid NVH problems of the mechanically driven pump. Furthermore, this makes it possible to provide a particularly advantageous supply with the fluid in a manner which is particularly favourable in terms of installation space and weight.In a further embodiment of the invention, in order to realize a particularly space-saving and cost-effective construction of the electric drive device, it is provided that the electric drive device has a branch valve arranged in the circuit between the first pump connection and the first stator connection, which branch valve 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 rotational direction and thus the delivery element is rotated in the first element rotational direction. The branch valve is switchable between a branch state and a closing state. In the branch state, at least a portion of the fluid conveyed by means of the pump can be branched off from the circuit via the branch valve and can thereby be discharged from the circuit. The branched-off fluid can be supplied, for example, to at least one consumer arranged outside the circuit, such as the rotor, so that a particularly advantageous fluid supply can be produced in a particularly simple manner.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 easily provided.In a further, particularly advantageous embodiment of the invention, the electric drive device has a second electric machine, which is provided in particular in addition to the first electric machine and has a second stator, which is arranged in the circuit and is connected fluidically in parallel 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 both stators with the fluid.In particular, the motor vehicle can be electrically driven, in particular purely, by means of the second electric machine.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 from outside the circuit with the fluid conveyed by means of a second pump provided in addition to the first pump. 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 introduction 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 introduction point, wherein the first introduction 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 introduction 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 introduction point, wherein the second introduction point is preferably spaced apart from the second point and the first connection point. By means of the valve device, a so-called boost function, i.e. a so-called support function, can be realized. During or through the support function, the fluid conveyed by means of the second pump is conveyed into the circuit as additional fluid at the introduction point, so that the stator can be supplied both with the fluid conveyed by means of the first pump and also with the fluid conveyed by means of the second pump. This allows the stator to be effectively and efficiently cooled and / or lubricated.Finally, in a further development of the invention, it has been shown to be particularly advantageous if the second pump is arranged in a line arrangement through which the fluid can flow, through which the fluid can be conveyed by means of 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 line arrangement, such that, for cooling and / or lubricating the rotors, the rotors can be supplied via the line arrangement with the fluid conveyed by means of the second pump. In the line arrangement, for example, additionally or alternatively a parking lock can also be arranged, which can be supplied with the fluid delivered by means of the second pump and by the pressure provided by the second pump, as a result of which the parking lock can be introduced and / or disengaged, wherein the second pump is provided very particularly advantageously for providing a higher pressure compared to the first pump and for delivering a lower volume flow. A fluid supply of further elements, in particular of transmission elements, which have to be cooled, lubricated or in particular actuated, can likewise be integrated into the line arrangement. Most particularly advantageously, by means of the second pump and the line arrangement, actuating devices of multi-plate clutches or brakes, which require a comparatively high pressure of at least several bar for actuation, are supplied with fluid by the second pump and the line arrangement. However, claw clutches or brakes can also be integrated into the line arrangement, wherein the second pump then provides a higher pressure compared to the first pump, which pressure is in particular higher than a maximum pressure which is permissible for cooling stators in stators. In this way, a particularly energy-efficient supply of the fluid can be ensured.Further advantages, features and details of the invention are evident from the following description of preferred exemplary embodiments and with reference to the drawing. The features and combinations of features mentioned above in the description and 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 respectively specified combination but also in other combinations or alone without departing from the scope of the invention.The drawing shows in: FIG. 1 shows a schematic illustration of a first embodiment of an electric drive device for a motor vehicle; FIG. 2 shows a schematic illustration of a second embodiment of the drive device in a detail; and FIG. 3 shows a schematic illustration of a third embodiment of the drive device in a detail.In the figures, identical or functionally identical elements are provided with identical reference symbols.FIG. 1 shows a schematic illustration of a first embodiment of an electric drive system 10 for a motor vehicle, which can be driven electrically, in particular purely, 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 thereby be rotated about a first machine rotational axis 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 thereby be rotated about a second machine rotational axis 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, by means of which the motor vehicle can be driven by the electric machines 12 and 18. A first part of the transmission is denoted by 24 and a second part of the transmission is denoted by 26. In FIG. 1, regions of the electric drive device 10 are designated by B 1, B 2 and B 3, wherein the regions B 1, B 2 and B 3 can be supplied with a coolant and / or lubricant which is preferably liquid and is very preferably formed as oil. The coolant and / or lubricant is also referred to as fluid. By supplying the respective region B 1, B 2, B 3 with the fluid, the respective region B 1, B 2, B 3 can be cooled and / or lubricated by means of the fluid. It can thus be seen from FIG. 1 that the stators 14 and 20, the rotors 16 and 22 and the transmission 23, and therefore 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 transmission 22 can be lubricated and / or cooled by means of the fluid.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, specifically optionally in a first flow direction illustrated by an arrow 32 or in a second flow direction illustrated by an arrow 34 and opposite the first flow direction. The pump 30 has a first pump port PA 1 and a second pump port PA 2. The pump 30 then has, if it is designed as a mechanically driven pump, a delivery element 36 by means of which the fluid can be delivered through the circuit 28 selectively in the first flow direction or in the second flow direction. The delivery element 36 is arranged in a pump housing of the pump 30 and is rotatable relative to the pump housing about an element axis of rotation. Here, the delivery member 36 may be selectively rotated in a first member rotational direction or in a second member rotational direction opposite to the first member rotational direction about the member rotational axis relative to the pump housing. By rotating the delivery element 36 in the first rotational direction about the element rotational axis and relative to the pump housing, the fluid is delivered through the circuit 28 in the first flow direction by means of the delivery element 36. By rotating the delivery element 36, which is also referred to as pump element, in the second rotational direction about the element rotational axis and relative to the pump housing, the fluid is delivered 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.In order to drive the motor vehicle forward, that is to say in order to bring about a forward drive of the motor vehicle, 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, that is to say in order to drive the motor vehicle backward in the opposite direction to the forward drive, the at least one rotor 16, 22 is rotated in a second rotor rotational direction, which is opposite the first rotor rotational direction, about the machine rotational axis relative to the associated stator 20, 22. In the exemplary embodiment shown in the figures, for example, the at least one rotor 16, 22 is the rotor 16. the pump 30, that is to say the delivery element 36, can be driven by the at least one rotor 16, such that, by rotating the rotor 16 in the first rotor rotational direction about the first machine rotational axis and relative to the stator 20, the delivery element 36 of the pump 30 can be rotated in the first element rotational direction about the element rotational axis relative to the pump housing, as a result of which the fluid can be delivered in the first flow direction through the circuit 28, can be delivered away from the pump 30 via the first pump connection PA 1 and can be delivered towards the pump 30 via the second pump connection PA 2. It follows from this that, by rotating the rotor 16 in the second rotor rotational direction about the first machine rotational axis and relative to the stator 20, the delivery element 36 is rotatable about the element rotational axis relative to the pump housing in the second element rotational direction opposite the first element rotational direction, whereby the fluid can be delivered through the circuit 28 in the second flow direction opposite the first flow direction, can be delivered away from the pump 30 via the second pump connection PA 2 and can be delivered towards the pump 30 via the first pump connection PA 1.Furthermore, it is provided that the circuit 28 is designed as a system closed with respect to ambient air. In addition, the respective stator 14, 20 has a respective first stator connection SA 1, which is fluidically connected to the first pump connection PA 1. The respective stator 14, 20 also has a respective, second stator connection SA 2, which is fluidically connected to the second pump connection PA. If the rotor 16 is rotated in the first rotor rotational direction and, as a result, the delivery element 36 is rotated in the first element rotational direction, the pump 30 is thereby operated in a first operation. If the rotor 16 is rotated in the second rotor rotational direction and, as a result, the delivery element 36 is rotated in the second element rotational direction, the pump 30 is operated in a second operation of the pump 30. In the first operation of the pump 30, the stators 14 and 20 are supplied with the fluid via the first stator ports SA 1, and the fluid is discharged from the stators 14 and 20 via the second stator ports SA 2. In the second operation of the pump 30, the stators 14 and 20 are supplied with the fluid via the second stator ports SA 2, and the fluid is discharged from the stators 14 and 20 via the first stator ports SA 1. For example, the delivery element 36 of the pump 30 is permanently connected to the rotor 16 in a torque-transmitting manner, in particular permanently in a rotationally fixed manner.It can be seen from 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 S 1 of the circuit 28 arranged between the first pump connection PA 1 and the respective first stator connection SA 1 and a second point S 2 of the circuit 28 arranged between the second stator connection SA 2 and the second pump connection PA 2 can be or are connected fluidically to one another. In this case, a shuttle valve 40 and a first pressure limiting valve 42 are arranged in the fluid connection 38.The shuttle valve 40 has exactly one closure element which is movable relative to the surroundings of the shuttle valve 40, in particular in a translatory manner. The shuttle valve 40 also has two flow cross sections Q 1 and Q 2 that can be closed by means of the closure element and a connection point AS, to which the pressure limiting valve 42 is connected, for example. The connection point AS is arranged between the flow cross sections Q 1 and Q 2 that can be closed by means of the closure element, wherein the closure element is in particular designed as a ball. In this case, the shuttle valve 40 always hydraulically connects the element 42 via that of the two points S 1 and S 2 to the circuit 28 at which the higher pressure level prevails, which takes place or can take place in particular in the second operation of the pump 30, such that, in particular in 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 limiting valve 42. In particular, in the first operation of the pump 30, the shuttle valve 40 prevents the fluid conveyed by the pump 30 in the first operation from flowing from the point S 1 to the point S 2, but the fluid can flow from the point S 1 with respect to the point S 2 and the pressure limiting valve 42 only to the pressure limiting valve 42, so that, for example, in the first operation by means of the pressure limiting valve 42 the pressure of the fluid can be limited to the maximum value. Thus, the pressure limiting 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 produced in a manner that is particularly advantageous in terms of installation space, weight and cost-effective.FIG. 2 shows a second embodiment of the drive device 10. The line element L 1 is fluidically connected to the circuit 28 at a first connection point V 1 arranged between the second stator connection SA 2 and the second pump connection PA 2. The second line element L 2 is a control line which is fluidically connected to the circuit 28 at a second connection point V 2 arranged between the first stator connection SA 1 and the first pump connection PA 1. A second pressure limiting valve 50 is arranged in the third line element L 3. An unlockable check valve 52 is provided, which is also referred to as a second check valve. The pilot-operated check valve 52 has a first valve connection to which the line element L 1 is connected, so that the first valve connection is fluidically connected to the first line element L 1. The pilot-operated check valve 52 has a second valve connection to which the second line element L 2 is connected, so that the second valve connection is fluidically connected to the second line element L 2. The pilot-operated check valve 52 has a third valve connection to which the line element L 3 is connected, so that the third valve connection is fluidically connected to the third line element L 3. Thus, for example, the third line element L 3 is fluidically connected at one end to the third valve connection, and at the other end, for example, the third line element L 3 opens into a pressure limiting valve 50. the pilot-operated check valve 52 can be unlocked by means of the fluid from the control line and has a locking direction which runs from the first valve connection to the third valve connection. If, for example, a pressure of the fluid in the line element L 2 acting on the check valve 52 and thus, for example, at the connection point V 2 is less than a threshold value, the check valve 52 is and remains blocked, that is to say closed, as a result of which the check valve 52 prevents a flow of the fluid in the blocking direction through the check valve 52, as a result of which the check valve 52 prevents a flow of the fluid from the first valve connection to the third valve connection. However, if the pressure of the fluid in the line element L 2 and thus at the connection point V 2 rises such that the pressure of the fluid in the line element L 2 and thus at the connection point V 2 corresponds to the threshold value or is greater than the threshold value, the unlockable check valve 52 is thereby unlocked, whereby the check valve 52 releases a flow of the 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 consequently can flow through the line element L 3. A pressure of the coolant and / or lubricant in the line element L 3 that is elevated in comparison with 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.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 SA 1 and the pump connection PA 1, in particular between the pump connection PA 1 and the point S 1 and very particularly between the connection point V 2 and the point S 1. By means of the branch valve 54, at least a portion of the fluid can be branched off from the circuit 28 and thereby be discharged from the circuit 28. The branch valve 54 is switchable between a branch state and a close state. In the branch state, at least the said part of the fluid can be branched off from the circuit 28 via the branch valve 54. In the closed state, branching of the fluid from the circuit 28 via the branch valve 54 is omitted.It can be seen from FIG. 1 that the drive device 10 has, for example in the first embodiment, 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 means of 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 over 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 conducted to a first introduction point E 1 arranged between the first pump connection PA 1 and the first stator connection SA 1 and introduced into the circuit 28 at the first introduction point E 1. In the second switching state, the fluid supplied to the valve device 56 via the supply connection VA can be conducted to a second introduction point E 2 arranged between the second pump connection PA 2 and the second stator connection SA 2 and introduced into the circuit 28 at the second introduction point E 2. In addition, it is provided that in the first switching state, at least a portion of the fluid can be or is guided from the introduction point E 2 via the valve device 56 to a pressure limiting valve 60, so that, for example, in particular in the first operation of the pump 30, a pressure of the fluid between the pump connection PA 2 and the stator connection SA 2 can be limited to a maximum value by means of the pressure limiting valve 60. For example, in 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 supplied from the first introduction point E 1 via the valve device 56 to the pressure limiting valve 60, so that, for example, in particular in the second operation of the pump 30, a pressure of the fluid between the pump connection PA 1 and the stator connection SA 1 can be limited to the maximum value by means of the pressure limiting 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 introduction point E 1 and the introduction point E 2 are fluidically separated from both the supply connection VA and the pressure limiting 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 transmission 23 are arranged in the line arrangement 66, so that the fluid can flow through the regions B 2 and B 3, and therefore the rotors 16 and 22 and the parts 24 and 26, via the line arrangement 66.In the first embodiment, a heat exchanger 68 is arranged in the circuit 28, by means of which heat exchanger the fluid flowing through the circuit 28 can be temperature-controlled, that is to say cooled and / or heated, in particular in such a way that a heat exchange between the fluid and an additionally provided temperature-control medium, which is in particular different from the fluid, can be exchanged via the heat exchanger 68. Alternatively or additionally, a heat exchanger 70 is arranged in the line arrangement 66, by means of which heat exchanger, for example, the fluid can be temperature-controlled, that is to say cooled and / or heated, in particular in that a heat exchange can take place between the fluid and, for example, the medium or another means via the heat exchanger 70. The second pump 58, which is designed as an electric pump, can be operated, for example, selectively in a third operation or in a fourth operation. In the third operation, the pump 58 delivers the fluid in a third flow direction through at least a portion of the conduit assembly 66, and in the fourth operation, the pump 58 delivers the fluid in a fourth flow through at least the portion of the conduit assembly 66, the fourth flow being opposite the third flow direction. The line arrangement 66 can be used, for example, for activating a parking lock P, by means of which the motor vehicle can be secured against undesired rolling away. In order to secure the motor vehicle by means of the parking lock P against undesired rolling away, the parking lock P is engaged, i.e. activated in order to enable rolling of the motor vehicle, the parking lock P is disengaged, i.e. deactivated. For example, to engage the parking lock P, the pump 58 is operated in the third mode or the fourth mode. In order to configure the parking lock P, for example, the pump 58 is operated in the fourth operation or the third operation. In particular, in the third operation, the rotors 16 and 22 and the parts 24 and 26 may be supplied with the fluid via respective valves 72 a- carranged in the conduit arrangement 66, in particular, for example, such that the rotors 16 and 22 are supplied with the fluid while supplying the parts 24 and 26 with the fluid is omitted and / or such that the parts 24 and 26 are supplied with the fluid while supplying the rotors 16 and 22 with the fluid is omitted and / or such that the rotors 16 and 22 and the parts 24 and 26 are simultaneously supplied with the fluid. In particular, the valve device 56 or the supply connection VA can be supplied via the valve 72 bwith the fluid conveyed by means of the second pump 58, wherein this takes place in particular in the third operation of the pump 58. In particular, it is possible to supply the supply port VA with the fluid while no supply of the rotors 16 and 22 and / or supply of the parts 24 and 26 with the fluid is occurring. It is also conceivable to simultaneously supply the supply connection VA and the rotors 16 and 22 with the fluid.It can be seen in particular from FIG. 1 that the drive device 10 is distinguished by the in particular completely closed circuit 28, which is very in particular an, in particular completely, closed oil circuit. In this oil circuit, the fluid presently designed as cooling oil can be pumped in a circuit by means of the pump 30, wherein the high-pressure and low-pressure side of the pump 30 is formed depending on the direction of rotation of the delivery element 36. For example, by means of the pressure limiting valve 42 and / or by means of the pressure limiting valve 60, the pressure of the fluid can be limited to the maximum value on the respective high-pressure side. In the case of a reversal of the direction of rotation of the pump 30, the pressure conditions rotate in such a way that the side which is the high-pressure side in the first operation is the low-pressure side in the second operation and that the side which is the low-pressure side in the first operation is the high-pressure side in the second operation. The drive device 10 makes it possible, in particular by using the shuttle valve 40, for the high-pressure side, that is to say both in the first operation and in the second operation, for the high-pressure side to be connected to the pressure limiting valve, in particular 42. The valve device 56 has a similar function; this can ensure that the low-pressure side is always connected to the second pressure limiting valve 60, as a result of which, when the additional fluid is introduced into the circuit 28 at the respective introduction point E 1, E 2, the pressure on the low-pressure side is limited to the maximum value. 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 assist state, is hereby 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 realize a particularly high volume flow of the fluid in the circuit 28. For this purpose, the additional fluid is introduced from the line arrangement 66 via the valve device 56 selectively into the circuit 28 at the introduction point E 1 or E 2.At least the following advantages can be realized:high system efficiency, since:Pressure resistances in the main flow of the circuit 28 result only from the stator, cooler and line (no valve or filter);because of the filter-free closed circuit of the circuit 28, the latter does not have to be designed for high volume flows, thus reducing costs;pressure requirements are separated by rotor cooling, transmission lubrication and P-actuations of volume flow requirements (for example stator) of the circuit 28. This reduces the power losses on the basis of the concept.pressure-sensitive components, such as stators or coolers, are decoupled from actuators which require an increased pressure level for switching or can provide pressure pulses in the system.In the case of a mechanically driven pump, no expensive graetz circuit is required to protect pumps and the system.improving NVH performance of pump 30, particularly at high cooling volume demands.In the second embodiment, for example, the valve device 56, which is omitted, is replaced by the line elements L 1, L 2 and L 3 and the check valve 52, wherein, for example, the pressure limiting valve 50 can be the pressure limiting valve 60 of the first embodiment. This allows the system to be simplified. However, this may result in the boost state being possible or advantageous or permissible only in one of the rotational directions of the pump 30, and in the present case for example in the first operation, and therefore in the first element rotational direction. According to FIG. 2, the boost state is only permitted, for example, in 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, whereby the pressure limiting valve 50 is released on the low-pressure side, in particular for a flow from the connection point V 1 to the pressure limiting valve 50.In the fifth embodiment, the heat exchanger 68 is provided in particular as a particularly powerful heat exchanger, very particularly as a particularly powerful cooler. In order to supply further consumers, such as the rotors 16 and 22 and / or at least one third rotor of a third electric machine, for example, the branch valve 54 is used, via which the fluid branched off from the circuit 28 can be supplied to the respective consumer.List of reference characters10 Drive device 12 First electric machine 14 First stator 16 First rotor 18 Second electric machine 20 Second stator 22 Second rotor 23 Transmission 24 Part 26 Part 28 Circuit 30 First pump 32 Arrow 34 Arrow 36 Delivery element 38 Fluid connection 40 Check valve 42 Pressure limiting valve 46 Base element 48 Spring 50 Pressure limiting valve 52 Pilotable check valve 53 Tank 54 Branch valve 56 Valve device 58 Second pump 60 Pressure limiting valve 66 Line arrangement 68 Heat exchanger 70 Heat exchanger 72 a- c Valve B 1 Region B 2 Region B 3 Region SA 1 First stator connection SA 2 Second stator connection S 1 First point S 2 Second point VA Supply connection E 1 First introduction point E 2 Second introduction point BA 1 First pump connection BA 2 Second pump connection p Park lock Q 1 Flow cross section Q 2 Flow cross section A 2 Connection point L 1 First line element L 2 Second line element L 3 Third line elementReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2015 219 503 A1

[0002]

Claims

Electric drive device (10) for a motor vehicle, having at least one first electric machine (12), which has a stator (14) and a rotor (16), having a circuit (28), through which a coolant and / or lubricant can flow, in which circuit the stator (14) is arranged, which circuit is to be cooled and / or lubricated by means of the coolant and / or lubricant, and having a pump (30), which is arranged in the circuit (28) and has a first pump connection (PA1) and a second pump connection (PA2), and by means of which the coolant and / or lubricant can be conveyed through the circuit (28), wherein: - in order to bring about a forward travel of the motor vehicle, the rotor (16) can be rotated relative to the stator (14) in a first rotor rotational direction; - for effecting a reverse travel of the motor vehicle, the rotor (16) is rotatable relative to the stator (14) in a second rotor rotation direction opposite the first rotor rotation direction; - the pump (30) is drivable by the rotor (16), such that: o, by rotating the rotor (16) in the first rotor rotation direction, a conveying element (36) of the pump (30) is rotatable in a first element rotation direction, as a result of which the coolant and / or lubricant is conveyable in a first flow direction (32) through the circuit (28), is conveyable away from the pump (30) via the first pump connection (PA1) and is conveyable towards the pump (30) via the second pump connection (PA2); o, by rotating the rotor (16) in the second rotor rotational direction, the delivery element (36) can be rotated in a second element rotational direction opposite the first element rotational direction, as a result of which the coolant and / or lubricant can be delivered through the circuit (28) in a second flow direction (34) opposite the first flow direction (32), can be delivered away from the pump (30) via the second pump connection (PA2) and can be delivered to the pump (30) via the first pump connection (PA1); - the circuit (28) is designed as a system closed with respect to ambient air; - a first stator connection (SA1) of the stator (14) is fluidically connected to the first pump connection (PA1); and; and - a second stator connection (SA 2) of the stator (14) is fluidically connected to the second pump connection (PA 2).Electric drive device (10) according to Claim 1, characterized in that the delivery element (36) of the pump (30) is permanently connected to the rotor (16) in a torque-transmitting manner.Electric drive device (10) according to Claim 1 or 2, characterized in that the delivery element (36) of the pump (30) is permanently connected to the rotor (16) in a rotationally fixed manner.Electric drive device (10) according to one of the preceding claims, characterized in that the circuit (28) is free of a filter device for filtering the coolant and / or lubricant.Electric drive device (10) according to one of the preceding claims, characterized bya 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 fluidically to one another.Electric drive device (10) according to Claim 5, characterized in that a shuttle valve (40) and a pressure limiting valve (42) are arranged in the fluid connection (38).Electric drive device (10) according to Claim 6, characterized in that the shuttle valve (40) has exactly one closure element and two flow cross sections (Q1, Q2) which can be closed by the closure element, wherein a connection point (AS) for the pressure limiting valve (42) is arranged between the closable flow cross sections (Q1, Q2).Electric drive device (10) according to Claim 6 or 7, characterized in that the closure element (44) of the shuttle valve (40) is designed as a ball.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 limiting valve (50) is arranged; a nonreturn valve (53) which can be unlocked from the control line by means of the coolant and / or lubricant and which has: o a first valve connection which is fluidically connected to the first line element (L1); o a second valve connection which is fluidically connected to the second line element (L2); and o a third valve connection which is fluidically connected to the third line element (L3), a locking direction of the unlockable nonreturn valve (52) running from the first valve connection to the third valve connection.Electric drive device (10) according to one of the preceding claims, characterized bya branch valve (54) which is arranged in the circuit (28) between the first pump connection (PA1) and the first stator connection (SA1) and can be switched over between: - a branch state in which at least some of the coolant and / or lubricant can be branched off from the circuit (28) via the branch valve (54) and can thereby be discharged; and - a closing state in which the coolant and / or lubricant does not branch off from the circuit (28) via the branch valve (54).Electric drive device (10) according to one of the preceding claims, characterized bya cooling device (68), which is arranged in the circuit (28), for cooling the coolant and / or lubricant.Electric drive device (10) according to one of the preceding claims, characterized bya second electric machine (18) which has a second stator (20) which is arranged in the circuit 828) and is connected in parallel with the first stator (14).Electric drive device (10) according to one of the preceding claims, characterized bya 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 over between: o a first switching state, in which the coolant and / or lubricant supplied to the valve device (56) via the supply connection (VA) can be conducted to a first introduction 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 introduction point (E1); and o a second switching state, in which the coolant and / or lubricant supplied to the valve device (56) via the supply connection (VA) can be conducted to a second introduction 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 introduction point (E2).Electric drive device (10) according to Claims 12 and 13, characterized in 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) is arranged as a first rotor (16) and a second rotor (22) of the second electric machine (18) 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 means of the second pump (58), as a result of which the parking lock (P) can be inserted and / or disengaged; and a transmission (23) is arranged in the line arrangement (66), by means of which transmission the motor vehicle can be driven by means of the electric machines (12, 18), wherein, for cooling and / or lubricating and / or actuating shift elements of the transmission (23), the transmission (23) can be supplied via the line arrangement (66) with the coolant and / or lubricant delivered by means of the second pump (58).

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