Device for transferring liquids

Abstract

To provide a liquid transfer device, specifically a gerotor pump, with a larger theoretical transfer volume but with the same or reduced required footprint. The present invention relates to a gerotor pump, a device for transferring liquids. The device includes a housing having a flange enclosing a volume, an outer rotor mounted for rotation about a longitudinal axis and an inner rotor of a displacement mechanism, and an electric drive rotor. The electric drive rotor is integrally formed with the outer rotor. The flange is also integrally formed with an eccentric for receiving the inner rotor and a conical bearing member extending in the direction of the longitudinal axis for receiving the outer rotor. The present invention relates to the use of the device for transferring liquids in a vehicle, for lubricating and cooling gears using oil or liquid, or for cooling a battery or an electric engine.

Description

[Technical Field]

[0001] The present invention relates to a liquid transfer device, a gear pump, and more particularly to an annular gear pump or gerotor pump. The device includes a housing enclosing a volume and including a flange, an outer rotor mounted for rotation about a longitudinal axis, an inner rotor of a displacement mechanism, and an electric drive rotor. The electric drive rotor is integrally formed with the outer rotor of the displacement mechanism. The device is preferably used in automobiles to lubricate and cool gears using oil as a liquid. [Background technology]

[0002] Gear pumps known from the prior art, particularly annular gear pumps, also known as gerotor pumps, have an inner rotor and an outer rotor. The outer rotor can be integrally connected to the rotor of an electric drive, particularly an electric motor. The rotors are arranged in a housing closed by a flange. The rotor of the electric motor of the gerotor pump and the outer rotor of the displacement mechanism are fixed to a rotatably mounted shaft.

[0003] The shaft is supported by the flange via bearings. The shaft is attached to the flange area in an axially oriented opening in the eccentric part. The eccentric part is integrally formed with the flange. The inner rotor is driven by the outer rotor and guided from the outside of the eccentric part. Liquid is transported from the suction area or inlet to the pressure area or outlet in an intermediate space, also known as the gerotor cell, located between the outer and inner rotors.

[0004] German Patent DE 102019200560 A1 discloses a gerotor pump of this type, in which the rotor of the electric motor and the associated outer rotor of the displacement mechanism are formed separately. The shaft is designed as a hollow shaft with an axially oriented through-hole as a pressure equalizer. This ensures pressure equalization between the motor space, a volume surrounded by the housing in which the rotor of the electric motor is located, and the suction area formed inside the flange.

[0005] For example, a liquid, such as gear lubricant, can flow from the motor space into the suction area through a through-hole in the hollow shaft, which is fitted with a plate to minimize leakage. In addition to pressure equalization, the leak flow can also be used, for example, to cool the control device of a gerotor pump.

[0006] To ensure sufficient flange strength, the bearing of the hollow shaft inside the flange's axial opening and the bearing of the inner rotor, which is part of the flange and located outside the eccentric, require a certain wall thickness between the inside and outside of the eccentric. The minimum outer diameter of the shaft is also limited by the inner diameter of the through-hole formed in the shaft. The required wall thickness of the eccentric and the required inner diameter of the through-hole formed in the shaft limit the minimum diameter of the inner rotor's profile, particularly the root diameter, and ultimately limit the possible transport volume of a gerotor pump with the same space. As a result, simply increasing the outer diameter of the outer rotor and housing while keeping the number of gerotor cells the same is possible, but in this case, the gerotor pump's installation space will be larger. Summary of the Invention [Problem to be solved by the invention]

[0007] It is an object of the present invention to provide a liquid transfer device, in particular a gerotor pump, which has a larger theoretical transfer volume than devices known from the prior art but requires the same or a reduced footprint. The device should be simple to manufacture and can be assembled in a time-saving manner. [Means for solving the problem]

[0008] This object is achieved by subject matter having the features of the independent claims, with further examples being set out in the dependent claims.

[0009] The object of the present invention is achieved by a liquid transfer device, particularly a gerotor pump, according to the present invention, which includes a housing having a flange enclosing a volume, an outer rotor mounted for rotation about a longitudinal axis, an inner rotor of a displacement mechanism, and an electric drive rotor, the electric drive rotor being integrally formed with the outer rotor of the displacement mechanism.

[0010] In accordance with the concept of the present invention, the flange has an eccentric portion for receiving the inner rotor and a longitudinally extending peg-like bearing member for receiving the outer rotor, and in accordance with the present invention, the flange is integrally formed with the eccentric portion and the bearing member. The outer rotor is mounted for rotation about the longitudinal axis with the bearing member, and the inner rotor is arranged to rotate about an eccentric portion inside the outer rotor. The rotor of the electric drive is arranged on a flanged pile-like bearing member oriented along the longitudinal axis for rotation about the longitudinal axis with the outer rotor of the displacement mechanism.

[0011] The integral molding of the flange, eccentric and bearing member means that the bearing member is fixed and non-movable relative to the housing or flange, and is therefore arranged to be fixed and non-rotatable. Integral molding means that it is formed from a single member, for example a single part-molded member. However, integral molding also includes that it is formed from multiple members that are fixedly formed together, in particular pressed together.

[0012] The bearing member is preferably at least substantially cylindrical in shape with a constant outer diameter in the longitudinal direction. Furthermore, the bearing member advantageously protrudes from a free end face of the eccentric portion facing the housing. If the housing is formed as a substantially hollow cylindrical member with a closed first end face, the flange closes a second end face of the housing formed distally from the first end face.

[0013] According to an embodiment of the invention, the bearing member comprises on its lateral surface a first bearing surface for guiding the rotor of the electric drive together with the outer rotor, and a second bearing surface for guiding the inner rotor driven by the outer rotor is preferably provided on the outside of the eccentric part.

[0014] According to an advantageous embodiment of the invention, the fluid connection of the pressure equalization device is formed between the motor space and the suction space as a volumetric region enclosed by a housing having a flange, in which the motor space together with the flange constitutes a first part of the volume enclosed by the housing, and the external rotor and the internal rotor of the displacement mechanism are arranged in a second part of the volume.

[0015] According to a first alternative embodiment of the present invention, the flange is part of a pressure equalization device and includes an axial through-opening at least in the region of the bearing member and the eccentric portion. The through-opening preferably begins at the first free end face and extends axially to the interior of the bearing member. The through-opening is preferably oriented coaxially with the longitudinal axis of the device. The through-opening can include a throttling device for the liquid.

[0016] The flange may include a flattened region within the region of the cylindrical eccentric portion, the flattened region being formed on an outer lateral surface of the eccentric portion.

[0017] According to a second alternative embodiment of the present invention, the flange includes flattened regions in the region of the cylindrical bearing member and the region of the cylindrical eccentric. The flattened regions are formed on the respective outer lateral surfaces. In this case, a first flattened region extends axially over the entire length of the eccentric, starting from the first free end face and ending at the second end face of the eccentric, where the eccentric is integrated into the region of the flange that closes the housing. Through the first flattened region, a flow path is formed between the eccentric and the inside of the internal rotor of the displacement mechanism. The flange preferably includes a radial groove extending between the first flattened region and the suction region of the device.

[0018] Another advantage of the present invention is that the second flattened area starts from the first free end face and extends axially to the second end face of the bearing element, where the bearing element is eccentrically connected to the eccentric end face facing towards the housing. Via the second flattened area, a flow path is formed between the bearing element and the inside of the rotor of the electric drive.

[0019] The second planarized region can extend axially continuously over the entire length of the bearing member, or can be formed in at least two sections, each extending axially over a portion of the length of the bearing member, with the at least two sections of the second planarized region preferably positioned radially opposite each other on the bearing member and axially offset from each other.

[0020] The flattened areas and grooves formed on the outer diameter of the cylindrical bearing surface, respectively, are beveled or chamfered to provide flow passages for concentrated leakage of liquid. By adjusting the flow cross section between the chamfer and the bearing surface or groove, a throttling function can also be realized. The advantageous design of the present invention allows for the use of devices for transporting liquids within a vehicle, particularly devices for lubricating and cooling gears using oil or liquid, or devices for cooling batteries or electric engines. [Effects of the Invention]

[0021] In summary, the device according to the invention has various advantages: (a) Achieving a larger conveyance volume in the same or smaller footprint, or the same conveyance volume in a smaller footprint, compared to previously known devices. (b) Minimization of components, for example, no separate shaft is required to guide the rotor of the electric drive or the external rotor compared to conventional devices, which also brings the following benefits: (c) Minimized production and assembly costs. [Brief explanation of the drawings]

[0022] Embodiments of the present invention will now be described with reference to the drawings in which: [Figure 1a] 1 is a side view showing a gerotor pump according to the prior art, which includes a housing closed by a flange, an outer rotor arranged on a rotatably mounted shaft, an inner rotor, and a device for pressure equalization between the suction area and the motor space. [Figure 1b] 1 is a front view showing a gerotor pump according to the prior art, which includes a housing closed by a flange, an outer rotor arranged on a rotatably mounted shaft, an inner rotor, and a device for pressure equalization between the suction area and the motor space. [Figure 2a] 1 shows a cross-sectional side view of a gerotor pump in which the outer rotor is mounted on a pile-shaped bearing member formed integral with the flange. [Figure 2b] 1 shows a cross-sectional front view of a gerotor pump in which the outer rotor is mounted on a pile-like bearing member formed integrally with the flange. [Figure 2c] 2a and 2b show a flange integrally formed with a bearing member for accommodating the outer rotor of the gerotor pump in a perspective view; [Figure 3a]1 is a cross-sectional side view of a first embodiment of a gerotor pump having an axial through-opening and an outer rotor mounted on a pile-shaped bearing member integrally formed with a flange as a device for pressure equalization between the suction area and the motor space; FIG. [Figure 3b] FIG. 1 is a cross-sectional front view of a first embodiment of a gerotor pump having an axial through-opening and an outer rotor mounted on a pile-shaped bearing member integrally formed with a flange as a device for pressure equalization between the suction area and the motor space. [Figure 3c] 3a and 3b show a flange of the gerotor pump in a perspective view. [Figure 4a] FIG. 1 shows a second embodiment of a gerotor pump in cross section, with a flattened area as a device for pressure equalization between the suction area and the motor space, and with the outer rotor mounted on a pile-shaped bearing member formed integrally with the flange. [Figure 4b] FIG. 1 shows a second embodiment of a gerotor pump in cross section in front, with a flattened area as a device for pressure equalization between the suction area and the motor space, and with the outer rotor mounted on a pile-shaped bearing member formed integrally with the flange. [Figure 4c] 4a and 4b show a flange of the gerotor pump in a perspective view. [Figure 5a] 1 shows a third embodiment of a gerotor pump in which the external rotor is arranged on a pile-shaped bearing member formed integrally with a flange, with two mutually opposed and axially offset sections of the flattened area as a device for pressure equalization between the suction area and the motor space. [Figure 5b] 1 shows a third embodiment of a gerotor pump in which the external rotor is arranged on a pile-shaped bearing member formed integrally with a flange, with two mutually opposed and axially offset sections of the flattened area as a device for pressure equalization between the suction area and the motor space. [Figure 5c] 5a and 5b show a flange of the gerotor pump in a perspective view. DETAILED DESCRIPTION OF THE INVENTION

[0023] 1a and 1b show a prior art liquid transfer device 1', in particular a gerotor pump, in side and front views. The device 1' consists of a housing 2 closed by a flange 3', an outer rotor 6 arranged on a rotatably mounted shaft 4', an inner rotor 7, and a device for equalizing the pressure between the motor space 2a and the suction area 8.

[0024] The cylindrical housing 2 is substantially hollow and cylindrical, having a first closed end face. A second end face, formed distal to the first end face, is closed by a flange 3'. The motor space 2a, coupled with the flange 3', constitutes a first portion of the volume enclosed by the housing 2, while the outer rotor 6 and inner rotor 7 of the displacement mechanism are located in a second portion of the volume. Both portions together form the volume enclosed by the housing 2.

[0025] The rotor 21 of the electric motor 20, having rotor laminations 21a, is disposed within the motor space 2a of the housing 2. The stator (not shown) of the electric motor 20 includes a stator lamination stack with coil windings, which are embedded in plastic along with the stator lamination stack. For example, plastic is molded using an injection molding process to form the housing 2. The stator and rotor 21 of the electric motor 20 extend along a common longitudinal axis 5, which defines the axis of rotation of the rotor 21. The stator is positioned radially outward of and surrounds the rotor 21. The flange 3' can also be formed of plastic, preferably the same plastic as the housing 2, or metal.

[0026] The rotor laminations 21a together with the permanent magnets (not shown) are overmolded with plastic so that the rotor 21 of the electric motor 20 is integrally formed with the external rotor 6 of the displacement mechanism. As a result, both the rotor 21 of the electric motor 20 and the external rotor 6 of the displacement mechanism are formed from plastic so that the external rotor 6 is directly driven by the rotor 21 of the electric motor 20.

[0027] The rotor 21 of the electric motor 20, together with the external rotor 6 of the displacement mechanism, is connected to a shaft 4' mounted for rotation about a longitudinal axis 5. The shaft 4' is supported on one side by the housing 2 and on the other side by the flange 3' via bearings in each case. The shaft 4' is attached axially to the housing 2, radially and axially to the flange 3', and in an axially facing receiving opening 3b' in the flange 3' region. The receiving opening 3b' is provided in the flange 3' region formed by an eccentric portion 3a'. The eccentric portion 3a' is integrally formed as part of the flange 3'.

[0028] The internal rotor 7, driven by the external rotor 6 of the displacement mechanism, is mounted independently of the external rotor 6 on the outside of the eccentric part 3a' and is arranged so that the internal rotor 7 is eccentric with respect to the shaft 4' and the external rotor 6. The liquid to be transported by the device 1' is guided through an intermediate space provided between the internal rotor 7 and the external rotor 6 from a suction region 8, which is the inlet of the device 1', to a pressure region 9, which is the outlet of the device. The device 1' moves the liquid from a low pressure at the inlet to a high pressure at the outlet.

[0029] The liquid flows from the pressure zone 9 into the motor space 2a of the device 1' through the gap left between the outer rotor 6 and the flange 3', thereby applying a medium pressure level to the motor space 2a. The medium pressure present in the motor space 2a reduces the gap left between the outer rotor 6 and the flange 3' and increases the sealing effect of the outer rotor 6 against the flange 3'. The medium pressure level represents a pressure level between the pressure level of the suction zone 8 and the pressure level of the pressure zone 9.

[0030] The shaft 4' is formed as a hollow shaft with an axial through-opening 4a' as a separate element and as a device for pressure equalization between the motor space 2a and the suction area 8. Liquid, such as gear lubricant, entering the motor space 2a flows as a leakage flow from the motor space 2a back into the suction area 8 through the axial through-opening 4a' formed in the shaft 4'. A throttle device for minimizing liquid leakage can be formed in the axial through-opening 4a'. The leakage flow of liquid through the motor space 2a can dissipate waste heat generated, for example, in the device 1', in particular the electric motor 20. The leakage flow can also be used to lubricate the bearings of the shaft 4'.

[0031] Figures 2a and 2b show a liquid transfer device 1, in particular a gerotor pump, in side and front views, in which an external rotor 6 is arranged on a pile-shaped bearing element 4 formed integrally with a flange 3. Figure 2c shows a perspective view of the device 1 according to Figures 2a and 2b, showing the flange 3 formed integrally with the bearing element 4 for accommodating the external rotor 6. Identical components of the devices (1, 1') are provided with identical reference numerals. For an explanation of the function of similar components, reference is also made to the explanation given for the device 1' according to Figures 1a and 1b.

[0032] The essential difference between the prior art device 1' according to Figures 1a and 1b and the device 1 according to Figures 2a and 2b is that the shaft 4' is formed as a bearing member 4 coupled to a flange 3. Compared to the rotatable shaft 4' of the device 1', the bearing member 4 is rigid and immovable and therefore corresponds to a fixed shaft.

[0033] Thus, the rotor 21 of the electric motor 20 of the device 1, together with the external rotor 6 of the displacement mechanism, is mounted for rotation about the longitudinal axis 5 on a pile-shaped bearing member 4 oriented in the direction of the longitudinal axis 5. Like the eccentric 3a, the solid, non-rotating bearing member 4 is integrally formed with the flange 3 as part of it. The rotor 21 of the electric motor 20 and the external rotor 6 of the displacement mechanism are mounted directly on the flange 3, which can be considered a component of the housing 2. The cylindrical bearing member 4 has a constant outer diameter over its length in the longitudinal direction 5.

[0034] The integral formation of the flange 3 with the eccentric part 3a and the peg-shaped bearing element 4 protruding from the free end face of the eccentric part 3a facing the housing 2 means that it is not necessary to mount the rotating shaft 4 corresponding to the device 1' of Figures 1a and 1b in the flange 3' area within the axially oriented receiving opening 3b'. As a result, the flange 3 is formed without a receiving opening, which would weaken the flange 3 wall. Instead of a receiving opening formed in the flange 3 area formed as the eccentric part 3a for receiving the rotating shaft, the rigid bearing element 4, which is integral with the flange 3, has a first bearing surface 10 on its lateral surface for guiding the rotor 21 of the electric motor 20 together with the outer rotor 6. The outer side of the eccentric part 3a forms a second bearing surface 11 for guiding the inner rotor 7, which is driven by the outer rotor 6 of the displacement mechanism.

[0035] The device 1 includes a flattened area 12 on the cylindrical eccentric part 3a as a pressure equalization device. The flattened area 12, located on the outer lateral surface of the cylindrical shape with a circular cross section, extends axially over the entire length of the eccentric part 3a, thus extending from its free end face facing the housing 2 to its second end face. At the second end face, the eccentric part 3a is integrated into the area of ​​the flange 3 that closes the housing 2. The flattened area 12 on the eccentric part 3a creates a flow path between the eccentric part 3a and the inside of the internal rotor 7. In the transition area from the eccentric part 3a to the area of ​​the flange 3 that closes the housing 2, a radially extending groove 13 is formed in the flange 3. The groove 13 connects the flow path formed between the eccentric part 3a and the inner side of the internal rotor 7 to the suction area 8 of the device 1.

[0036] Via the flattened area 12 of the eccentric part 3a, via the intermediate space formed between the eccentric part 3a and the inside of the inner rotor 7 and the fluidically connected groove 13 thereto, and via the bearing play between the rotor 21 and the first bearing surface 10, a flow passage is ensured for the leakage flow of liquid from the motor space 2a to the suction area 8. The throttling function is provided by the bearing clearance between the rotor 21 and the first bearing surface 10.

[0037] Due to the integration of the shaft as a bearing member 4 in the flange 3 and therefore the omission of a receiving opening for supporting the rotatable shaft in the flange, the outer diameter of the eccentric part 3a as a bearing diameter of the internal rotor 7 of the device 1 is reduced compared to the prior art device 1' according to Figures 1a and 1b, while the wall thickness of the internal rotor 7 remains the same and / or the eccentricity of the device 1, in particular the internal rotor 7, is increased. Thus, the installation space of the device 1, in particular the outer diameter and longitudinal extent, remains the same compared to the prior art device 1', while the conveying volume can be increased. Alternatively, it is also possible to reduce the installation space of the device 1 while keeping the conveying volume the same.

[0038] 3a and 3b show a first embodiment of a gerotor pump in cross section from the side and in cross section from the front, in which the external rotor 6 is mounted on a pile-shaped bearing element 4-1 integrally formed with a flange 3-1 having an axial through-opening 4a, as a device for pressure equalization between the suction area 8 and the motor space 2a. FIG. 3c shows a perspective view of the flange 3-1 of the device 1-1 according to FIGS. 3a and 3b, in which the flange 3-1 is integrally formed with a bearing element 4-1 for accommodating the external rotor 6. Identical components of the device 1, 1-1 according to FIGS. 2a to 2c are designated by the same reference numerals. For a functional description of the identical components, reference is also made to the description of the device 1 according to FIGS. 2a to 2c.

[0039] The fundamental difference between the device 1 according to FIGS. 2a and 2b and the device (1-1) according to FIGS. 3a and 3b lies in the formation of the flange (3, 3-1) and the bearing element (4, 4-1) with the axial through-opening 4a. The axially oriented through-opening 4a is formed coaxially with the longitudinal axis 5 as a pressure equalization device between the motor space 2a and the suction area 8. The axial through-opening 4a thus constitutes a fluid connection between the motor space 2a of the device (1-1) and the suction area 8, so that the liquid flowing inside the motor space 2a, in particular the gear lubricant, can return as a leakage flow from the motor space 2a through the axial through-opening 4a to the suction area 8. The axial through-opening 4a, which extends axially from the first free end face to the interior of the bearing element (4-1) and the eccentric part (3a-1) of the flange (3-1), is formed with a liquid throttling device to minimize leakage. The axial through-opening 4a opens into the interior of the motor space 2a from the region of the first end face of the bearing element (4-1). The intermediate space formed between the eccentric part (3a-1) and the inside of the inner rotor 7 by the flattened area 12 of the eccentric part (3a-1) and the grooves 13 fluidly connected thereto are used for lubrication, cooling or pressure relief of the bearing.

[0040] To further increase the conveying volume while maintaining the same installation space of the device, or to reduce the installation space while maintaining the same conveying volume of the device, it is necessary to reduce the diameter of the pile-shaped bearing element. Figures 4a and 4b show a second embodiment of a gerotor pump in side and front views, in which the external rotor 6 is arranged on a pile-shaped bearing element (4-2) formed integrally with a flange (3-2) having a flattened area 14 as a device for pressure equalization between the suction area 8 and the motor space 2a. Figure 4c is a perspective view of the flange (3-2) formed integrally with the bearing element 4 for accommodating the external rotor 6 of the device (1-2) according to Figures 4a and 4b. Identical components of the devices (1, 1-1, 1-2) are provided with the same reference numerals. For an explanation of the function of similar components, reference is also made to the description of the device 1 according to Figures 2a and 2b.

[0041] The fundamental difference between the devices (1, 1-1, 1-2) is the design of the bearing elements (4, 4-1, 4-2) and flanges (3, 3-1, 3-2) for the pressure equalization device between the motor space 2a and the suction area 8. In the device (1-2) of Figures 4a and 4b, the pressure equalization device is provided by flattened areas (12, 14) on the cylindrical eccentric part (3a-2) and the cylindrical bearing element (4-2), respectively. The flattened areas (12, 14) are provided on the outer lateral surfaces of the cylinders with circular cross sections. In comparison with the device (1-1) of Figures 3a and 3b, the bearing element (4-2) and the eccentric part (3a-2) are round rods, each without axial openings, and made of a hard material.

[0042] 2a-2c, 3a-3c, the first flattened area 12 extends axially over the entire length of the eccentric part (3a-2), thus extending from its free end face facing the housing 2 to its second end face, which is integrated in the area of ​​the flange (3-2) that closes the housing 2. Via the first flattened area 12 of the eccentric part (3a-2), a flow path is formed between the eccentric part (3a-2) and the inside of the internal rotor 7.

[0043] In the transition region from the eccentric part (3a-2) to the region of the flange (3-2) closing the housing 2, the flange (3-2) is formed with a radially extending groove 13. The groove 13 connects the flow passage formed between the eccentric part (3a-2) and the inner flank of the internal rotor 7 with the suction region 8 of the device (1-2).

[0044] In contrast to the devices (1, 1-1) of Figures 2a-2c and 3a-3c, the second flattened area 14 extends axially over the entire length of the bearing element (4-2), i.e., from the first free end face to the second end face of the bearing element (4-2). At the second end face, the bearing element (4-2) is connected to the eccentric part (3a-2), in particular to the free end face of the eccentric part (3a-2) facing towards the housing 2. Via the second flattened area 14 of the bearing element (4-2), a flow path is ensured between the bearing element (4-2) and the outer rotor 6 or the inside of the rotor 21 of the electric motor 20.

[0045] The fluidly connected intermediate spaces and grooves 13 formed by the second flattened area 14 of the bearing element (4-2) between the bearing element (4-2) and the inner side of the outer rotor 6 or the rotor 21 of the electric motor 20, and by the first flattened area 12 of the eccentric element (3a-2) between the eccentric element (3a-2) and the inner side of the inner rotor 6, ensure a flow path for leakage of liquid from the motor space 2a to the suction area 8. A throttling function is provided by adjusting the depth of the grooves 13 or of the flattened areas (12, 14) radially.

[0046] By forming the flattened areas 12, 14 of the device 1-2 instead of the through-opening 4a of the device 1-1, the outer diameter of the eccentric part 3a-2, and therefore the inner diameter of the internal rotor 7, is less restricted than in the device 1-1 having the through-opening 4a according to Figures 3a to 3c. In particular, the outer diameter of the eccentric part 3a-2 of the device 1-2 can be lower than in the device 1-1, so that the entire flange 3-2, especially in the region of the bearing element 4-2, can be formed to have a smaller radius than the flange 3-1 of the device 1-1.

[0047] 5a and 5b show a side view and a front view of a third embodiment of a gerotor pump, in which the liquid transfer device (1-3) has two opposing, axially offset sections of the second flattened area 14 of the device for pressure equalization between the suction area 8 and the motor space 2a, and the external rotor 6 is arranged on a pile-like bearing element (4-3) formed integrally with the flange (3-3). Fig. 5c shows a perspective view of the flange (3-3) of the device (1-3) according to Figs. 5a and 5b, in which the flange (3-3) is formed integrally with the bearing element (4-3) for accommodating the external rotor 6. The same components of the devices (1, 1-1, 1-2, 1-3) are again provided with the same reference numerals. To explain the function of similar components, reference is also made to the description of the device 1 according to Figs. 2a to 2c.

[0048] The fundamental difference between the devices (1-2, 1-3) is that the pressure equalization device includes bearing elements (4-2, 4-3) and flanges (3-2, 3-3) between the motor space (2a) and the suction area (8). Compared to the flange 3-2 of the device (1-2) according to Figs. 4a and 4b, the flange (3-3) of the device (1-3) according to Figs. 5a and 5b includes two sections (14-1, 14-2) of the second flattened area 14 of the cylindrical bearing element (4-3) as a pressure equalization device. The two sections (14-1, 14-2) of the second flattened area 14 are arranged radially opposite each other and axially offset from each other on the outer lateral surface of the cylindrical shape, each having a circular cross section. The bearing element (4-3) is alternatively flat.

[0049] The alternative formation of the first and second sections (14-1, 14-2) of the second flattened area 14 on the bearing member (4-3) results in a stable positioning of the rotor 21 of the electric motor 20 or the outer rotor 6 on the bearing member (4-3). This helps, in particular, to prevent potential tilting of the outer rotor 6 relative to the bearing member (4-3) and the longitudinal axis 5. The opposing sections (14-1, 14-2) of the second flattened area 14 are designed to support the forces resulting from tilting of the outer rotor 6, with the sections (14-1, 14-2) located on the opposite side of the tilt. This reduces tilting of the outer rotor 6 of the device (1-3) compared to the design of the device (1-2). [Explanation of symbols]

[0050] 1, 1-1, 1-2, 1-3, 1' device 2. Housing 2a Motor space 3, 3-1, 3-1, 3-2, 3-3, 3' flange 3a, 3a-1, 3a-2, 3a-3, 3a' eccentric part 3b' Receptor opening 4, 4-1, 4-2, 4-3 Bearing parts 4' shaft 4a, 4a' Axial through opening 5 Vertical axis 6 External rotor 7 Internal Rotor 8 Suction Area 9 Pressure Regions 10 first bearing surface 11 second bearing surface 12 first flattened area of ​​the second bearing surface (11) 13 Home 14 Second flattened area (14) of first bearing surface (10) 14-1 First section of the second planarization area (14) 14-2 Second section of the second flattening area (14) 20 Electric Motor 21 rotor 21a Rotor lamination

Claims

1. 1. A gerotor pump, comprising: a housing (2) having flanges (3, 3-1, 3-2, 3-3) enclosing a volume; an outer rotor (6) mounted for rotation about a longitudinal axis (5) and an inner rotor (7) of a displacement mechanism; and an electric drive rotor (21) integrally formed with said external rotor (6), the flanges (3, 3-1, 3-2, 3-3) are integrally formed with eccentric portions (3a, 3a-1, 3a-2, 3a-3) for accommodating the inner rotor (7) and pin-shaped bearing members (4, 4-1, 4-2, 4-3) extending in the direction of the longitudinal axis (5) for accommodating the outer rotor (6); Transfer liquids, The bearing members (4, 4-1, 4-2, 4-3) are at least substantially cylindrical and formed with a constant outer diameter in the direction of the longitudinal axis (5); a fluid connection of the pressure equalization device between an engine space (2a) as a volumetric area enclosed by the housing (2) having flanges (3, 3-1, 3-2, 3-3) and a suction area (8); the flange (3, 3-1, 3-2, 3-3) includes a first flattened region (12) in the region of the eccentric portion (3a, 3a-1, 3a-2, 3a-3); The first planarized region (12) is formed on the outer lateral surface, the first flattened region (12) is formed extending in the axial direction over the entire length of the eccentric portion (3a, 3a-1, 3a-2, 3a-3) from a first free end surface to a second end surface of the eccentric portion (3a, 3a-1, 3a-2, 3a-3); The flange (3, 3-1, 3-2, 3-3) has a radially extending groove (13), the groove (13) being formed to extend between the first flattened region (12) and the suction region (8).

2. The device (1, 1-1, 1-2, 1-3) according to claim 1, characterized in that the bearing members (4, 4-1, 4-2, 4-3) are formed to protrude from the free end surfaces of the eccentric portions (3a, 3a-1, 3a-2, 3a-3) facing in the direction of the housing (2).

3. The device (1, 1-1, 1-2, 1-3) according to claim 1, characterized in that the lateral surfaces of the bearing members (4, 4-1, 4-2, 4-3) comprise bearing surfaces (10) for guiding, together with the external rotor (6), the rotor (21) of the electric drive device.

4. The device (1, 1-1, 1-2, 1-3) according to claim 1, characterized in that a bearing surface (11) for guiding the inner rotor (7) driven by the outer rotor (6) is formed on the outer side of the eccentric portion (3a, 3a-1, 3a-2, 3a-3).

5. The device (1, 1-1, 1-2, 1-3) according to claim 1, characterized in that the flange (3-1) is formed with an axial through-opening (4a) at least in the region of the bearing member (4-1) and the eccentric portion (3a-1).

6. The device (1, 1-1, 1-2, 1-3) according to claim 5, characterized in that the axial through opening (4a) is formed so as to start from the first free end face in the axial direction and extend inside the bearing member (401).

7. 6. The device (1, 1-1, 1-2, 1-3) according to claim 5, characterized in that the axial through opening (4a) is formed oriented coaxially with the longitudinal axis (5).

8. the flanges (3-2, 3-3) include flattened areas (12, 14, 14-1, 14-2) in the areas of the cylindrical bearing members (4-2, 4-3) and the eccentric portions (3a-2, 3a-3), respectively; 2. The device (1, 1-1, 1-2, 1-3) according to claim 1, characterized in that said planarized areas (12, 14, 14-1, 14-2) are formed on the outer lateral surfaces, respectively.

9. A gerotor pump, a housing (2) having flanges (3, 3-1, 3-2, 3-3) enclosing a volume; an outer rotor (6) mounted for rotation about a longitudinal axis (5) and an inner rotor (7) of a displacement mechanism; and an electric drive rotor (21) integrally formed with said external rotor (6), the flanges (3, 3-1, 3-2, 3-3) are integrally formed with eccentric portions (3a, 3a-1, 3a-2, 3a-3) for accommodating the inner rotor (7) and pin-shaped bearing members (4, 4-1, 4-2, 4-3) extending in the direction of the longitudinal axis (5) for accommodating the outer rotor (6); Transfer liquids, The bearing members (4, 4-1, 4-2, 4-3) are at least substantially cylindrical and formed with a constant outer diameter in the direction of the longitudinal axis (5); a fluid connection of the pressure equalization device between an engine space (2a) as a volumetric area enclosed by the housing (2) having flanges (3, 3-1, 3-2, 3-3) and a suction area (8); the flanges (3-2, 3-3) include flattened areas (12, 14, 14-1, 14-2) in the areas of the cylindrical bearing members (4-2, 4-3) and the eccentric portions (3a-2, 3a-3), respectively; The flattened regions (12, 14, 14-1, 14-2) are formed on the outer lateral surfaces, respectively; A device (1, 1-1, 1-2, 1-3) characterized in that a second flattened region (14, 14-1, 14-2) is formed starting from a first free end surface of the bearing member (4-2, 4-3) and extending axially to a second end surface.

10. 10. The device (1, 1-1, 1-2, 1-3) according to claim 9, characterized in that the second flattened area (14) is formed so as to extend continuously in the axial direction over the entire length of the bearing member (4-2).

11. The device (1, 1-1, 1-2, 1-3) according to claim 9, characterized in that the second flattened region (14) is composed of at least two sections (14-1, 14-2) each extending axially over a portion of the length of the bearing member (4-3).

12. 12. The device (1, 1-1, 1-2, 1-3) according to claim 11, characterized in that the at least two sections (14-1, 14-2) of the second flattened region (14) are arranged radially opposite each other and axially offset from each other on the bearing member (4-3).

13. A motor vehicle using a device (1, 1-1, 1-2, 1-3) according to any one of claims 1 to 12 for transporting liquids within the vehicle, for lubricating and cooling gears with oil or liquid, or for cooling a battery or an electric engine.

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