Brush holder for holding at least two electric brushes of a sliding contact device, electric machine and motor vehicle

Abstract

The invention relates to a brush holder for holding at least two electric brushes (10) of a sliding contact arrangement, comprising a middle element (7) and two contact elements (8, 9) for electrically contacting at least one of the electric brushes (10), wherein the contact elements (8, 9) are arranged on opposite sides (11, 12) of the middle element (7), the middle element (7) having a receiving portion (13) for a rotary shaft (6) extending through the opposite sides (11, 12).

Description

Technical Field

[0001] This invention relates to a brush holder for holding at least two brushes of a sliding contact device, the brush holder comprising an intermediate element and two contact elements for respectively electrically contacting at least one of the brushes. Furthermore, this invention relates to an electric motor and a motor vehicle. Background Technology

[0002] Sliding contact devices are used, for example, in separately excited motors, where they provide electrical contact for the rotor windings. For this purpose, a current loop is formed, for example, using two or more brushes, through which the rotor windings can be energized to generate an excitation magnetic field. Here, the brushes bring into contact with contact areas, such as contact rings, located on the rotating shaft. For this purpose, the brushes are typically fixedly positioned near the rotating shaft and maintain direct contact with the contact areas. Brush holders can be used to secure the brushes. Different types of sliding contact devices are known from the prior art.

[0003] JP 2017017940 A describes a sliding contact device in which a brush acts on the outer circumference of a contact ring. Here, a coolant can be loaded onto the contact surface between the brush and the contact ring, and this coolant can flow into the interior of a rotating shaft having the contact ring. For this purpose, a through-hole is provided on the circumference of the shaft, through which the flowing coolant draws the brush onto the contact surface of the sliding contact device.

[0004] A sliding contact device is disclosed in US 2013 / 0147310 A1, which includes a cavity filled with liquid metal. The liquid metal enables contact between the stationary and rotating components of the slip ring device.

[0005] JP 2015159655 A discloses a slip ring contact device including a cooling device disposed within a shaft. Here, the slip ring is contacted via a plurality of brushes arranged staggered along the axial direction of the shaft. Summary of the Invention

[0006] The objective of this invention is to provide an improved brush holder for holding at least two brushes of a sliding contact device, the brush holder having a particularly compact structural form.

[0007] To achieve this objective, according to the invention, in a brush holder of the type described at the beginning, contact elements are arranged on two opposing sides of an intermediate element, the intermediate element having a receiving portion for a rotating shaft extending through the opposing sides.

[0008] The intermediate element is electrically insulated, thereby electrically isolating the contact elements arranged on two opposite sides of the intermediate element. Thus, at least one brush can be contacted on one side via the contact elements. Therefore, a current loop can be formed, for example, for energizing the excitation winding of a separately excited motor, via two brushes or via two contact elements. The brushes can be, in particular, carbon brushes.

[0009] The intermediate element has a receiving portion extending between opposing sides. A rotating shaft can be arranged in this receiving portion, and in particular, two slip rings arranged offset along the axial direction of the shaft can be arranged on opposing sides of the intermediate element and in contact with brushes connected to contact elements.

[0010] The receiving part advantageously allows the brush holder to be arranged very close to the rotating shaft. Furthermore, the compact structure of the brush holder is achieved by arranging the two contact elements on opposite sides of the intermediate element. This particularly facilitates the arrangement of the brush holder on or within the motor, as it allows for a space-saving arrangement of the brushes in an environment close to the shaft.

[0011] Furthermore, the brush mating members can be constructed in a space-saving manner, particularly with the smallest possible space requirement along the axial direction of the shaft, for example, as contact rings on a rotating shaft. This also allows for space-saving implementation of the shaft. This also advantageously affects the motor, which can thus be implemented compactly and with minimal structural space.

[0012] The intermediate elements can be implemented as electrically insulating plastic parts, particularly as integral components, which can be manufactured, for example, by injection molding. The contact elements are conductive and, for example, made of metal. Preferably, the contact elements are constructed as plates, thereby advantageously achieving simple manufacturability of the brush holder.

[0013] According to the invention, the receiving portion can be configured as a through-hole or a recess / notch in the intermediate element. When the receiving portion is configured as a through-hole, the intermediate element completely surrounds the shaft in a plane perpendicular to the axis of rotation or the axial extension of the shaft. Alternatively, the receiving portion can be configured as a recess, so that the intermediate element only partially surrounds the shaft. Depending on the configuration of the receiving portion of the intermediate element, the intermediate element thus extends around the entire shaft or only partially surrounds the shaft. An intermediate element with a recess configured as a recess can, for example, be horseshoe-shaped or C-shaped. An intermediate element with a receiving portion configured as a through-hole can be annular or annular disc-shaped.

[0014] In a preferred embodiment of the invention, the intermediate element and / or contact element is an annular disc. The annular disc-shaped intermediate element may in particular have a receiving portion for a rotating shaft configured as a through-hole. By using the annular disc-shaped contact element, one or more brushes can be arranged on each opposite side of the intermediate element and these brushes can be electrically contacted by the contact element. Here, the use of the annular disc-shaped contact element particularly achieves simple electrical contact of multiple brushes arranged offset around the entire circumference of the rotating shaft.

[0015] To facilitate contact between the brushes via contact elements, according to the invention, the contact elements and the intermediate element each define at least one receiving section for receiving one of the brushes. The receiving sections can be configured to receive carbon brushes, which are typically square, respectively. The contact elements can be at least partially directly abutted against the intermediate element, wherein the receiving sections are formed by regions of the contact elements protruding from the intermediate element, these regions defining, for example, rectangular faces with the intermediate element. Thus, within these receiving sections, the brushes can be arranged respectively between the intermediate element and their respective contact elements. Through the receiving sections, the brushes can be fixed to the brush holder in the axial direction of the axis received in the receiving section.

[0016] According to the present invention, the regions defining the receiving sections on the sides of the intermediate element may each have rib structures. Therefore, the brushes arranged in the receiving sections can rest against the rib structures of the intermediate element. The rib structures reduce the contact area, thereby facilitating, for example, movement or clamping of the brushes toward the contact rings of the shaft. Furthermore, the rib structures also enable airflow to be generated between the brushes and the intermediate element, for example, due to the heat generated by the brushes. For example, the heat generated by the brushes can occur during the operation of the sliding contact device when current is conducted through the brushes. Additionally, the heat generated by the brushes may also be due to friction between the brushes and their corresponding mating parts on the sliding contact portion.

[0017] In a preferred embodiment of the invention, each contact element may have at least one contact segment that laterally protrudes beyond the intermediate element. Here, the contact segments may extend outward beyond the intermediate element, particularly in the radial direction of a rotating axis arranged in the receiving portion or in the radial direction of a substantially circular receiving portion. Wires, for example, can be fixed to the contact segments, through which the contact elements and, consequently, the brushes can be energized. For example, the contact segments may be substantially rectangular. One or both contact segments may have one or more openings into which conductive pins or the like can be inserted, for example, to simplify the connection of the contact segments to the pole shoes of the wires.

[0018] According to the invention, the contact elements can be specified to have the same geometry. This enables the contact elements on both sides of the intermediate element to be manufactured in the same manner, thereby advantageously reducing the number of different parts required for manufacturing the brush holder. Since the same parts are used for the contact elements, the structural complexity of the brush holder can be significantly simplified, and therefore the manufacturing of the brush holder can also be significantly simplified.

[0019] To improve heat dissipation from the brush holder, according to the invention, the intermediate element may have at least one cooling channel extending inside the intermediate element. The cooling channel may, for example, be connected to a cooling cycle or may be loaded with coolant, thereby dissipating heat from the interior of the intermediate element. Additionally or alternatively, the cooling channel may also be used to supply coolant to the brushes and / or other components of the sliding contact device, in order to cool the sliding contact device, particularly during operation.

[0020] Therefore, according to the invention, the intermediate element may be provided with at least one discharge opening of a cooling channel on at least one of the opposing sides. Specifically, the intermediate element may have at least one discharge opening of a cooling channel on each of the two opposing sides. Here, the discharge opening of the intermediate element is not covered by contact elements arranged on the same side, so that coolant can flow out from the discharge opening. The discharge opening allows coolant to be applied to the rotating shaft, particularly in the region of the sliding contact portion.

[0021] According to the invention, the discharge opening can be configured as a drain or nozzle. Through the drain, a coolant, particularly liquid, such as electrically insulating cooling oil, can be applied to the rotating shaft in the region of the sliding contact portion. The coolant can be pushed across the surface of the shaft as it rotates by brushes that contact the contact rings on the shaft, thus not affecting the electrical contact between the brushes and the annular contact portion. The oil appearing on the shaft can then flow away from the shaft, thereby dissipating heat from the brushes and / or the rotating shaft.

[0022] Alternatively, the drain hole may be constructed as a nozzle, through which a jet of liquid or gaseous coolant can be generated, directed toward the brush and / or shaft, particularly toward the contact ring of the shaft that can directly contact the brush. Heat dissipation from the brush and / or shaft can also be achieved by spraying liquid or gaseous coolant onto the sliding contact device.

[0023] In addition to the discharge opening, the intermediate element may also have one or more inlet openings through which cooling channels extending inside the intermediate element can be connected to a cooling device. Liquid or gaseous coolant may flow into, be forced into, or be sprayed into the cooling channels through the inlet openings.

[0024] In a preferred embodiment of the invention, the brush holder may include at least one clamping device, which applies a force to the brushes arranged on the brush holder, particularly a force directed toward the center of the shaft arranged in the receiving portion. This force may, for example, be directed toward the center of the receiving portion, which is configured as a circular through-hole. If the receiving portion is designed as an open section, the force may also be directed toward the center of the open section or toward the center of the rotating shaft arranged in the receiving portion, thereby pressing the brushes as radially inward as possible against the outer periphery of the shaft or against a contact ring arranged thereon.

[0025] The clamping device can be constructed, for example, as a helical spring, by means of which a force can be applied to the brush. The helical spring can be fixed to the contact element and / or the intermediate element. For example, the helical spring can be arranged around a protrusion of the contact element, wherein the outer periphery of the helical spring is held together at least partially by a receiving section of the intermediate element (particularly limited by an axial protrusion of the intermediate element). In this way, a compact arrangement of the helical spring on the brush holder and a simple structure of the brush holder can be achieved.

[0026] According to the invention, the intermediate element has at least one pin extending from a respective side on each of its opposing sides, the pins extending through corresponding through holes in adjacent contact elements, wherein the contact elements are respectively secured to the intermediate element by deformation of the pins. The intermediate element may, for example, be made of plastic and has at least one pin extending from each of its opposing sides.

[0027] When assembling the brush holder, the contact elements to be assembled on the respective sides can be arranged on the intermediate element, wherein pins are guided through the corresponding through holes of the contact elements. Subsequently, the pins can be deformed, for example by heating, so that the pins widen after passing through the through holes of the contact elements, thereby stably fixing the contact elements to the intermediate element. In particular, for fixing, multiple pins can be provided, each extending through a corresponding through hole of the contact element.

[0028] The motor according to the invention includes at least one brush holder according to the invention. Furthermore, the motor may particularly have a rotating shaft arranged in a receiving portion of an intermediate element of the brush holder. The rotating shaft may particularly have at least two contact rings arranged offset along the axial direction of the shaft, wherein at least one contact ring is in direct contact with brushes arranged or potentially arranged on a side of the brush holder. Here, the axis of rotation of the shaft may extend at least substantially perpendicular to the opposite side of the intermediate element on which the contact elements are arranged. The motor may have a separately excited rotor, which can be energized via the brush holder.

[0029] According to the invention, the brush holder can be arranged in a wet cavity of the motor, which is at least partially filled with an insulating coolant. The advantage of arranging the brush holder in the wet cavity of the motor is that no additional seal is required between the space where the brush holder is arranged and the wet cavity of the motor, which is at least partially filled with coolant. Here, sealing of the rotating shaft can be advantageously omitted, thereby resulting in less frictional loss, especially during rapid rotor shaft operation. The electrically insulating coolant in the wet cavity can be applied to the effective components of the rotor and / or stator, particularly by oil-spray cooling.

[0030] According to the invention, the intermediate element of the brush holder can be configured to have at least one cooling channel extending inside the intermediate element, wherein the intermediate element is at least partially abutted against the housing component of the motor, particularly the end cap, and the cooling channel is capable of supplying coolant through the cooling channel of the housing component. Here, the cooling channel of the housing component can particularly have a discharge opening directly opposite the inlet opening of the intermediate element disposed on the housing component, thereby connecting the cooling channel of the housing component and the cooling channel in the intermediate element. In this way, coolant, particularly coolant liquid, can be supplied from the cooling channel in the housing component to the cooling channel inside the intermediate element. Advantageously, this allows for coolant supply to the cooling channel extending inside the intermediate element in a space-saving manner.

[0031] As described above, the coolant supplied to the cooling channels within the intermediate element can be supplied to the brushes and / or shaft-side contact rings through the discharge opening of the intermediate element. The cooling oil flowing out of the sliding contact device can collect in the motor's cooling oil sump and be removed from there to cool the sliding contact device and / or other components of the motor.

[0032] According to the invention, a housing component can be arranged between the rotor and the brush holder of the motor, wherein coolant thrown towards the guide structure during rotor rotation can be supplied as coolant to a cooling channel of the housing component via at least one guide structure. The housing component can particularly be an end cap that supports a rotating shaft relative to the stationary housing of the motor. Here, the rotor of the motor can be arranged on one side of the housing component or the end cap. The brush holder can be arranged opposite the end cap, thereby allowing the guide structure to be arranged around the rotor.

[0033] This guide structure is specifically connected to the cooling channels of the housing component, so that the coolant thrown around by the rotor during rotation (which impacts the guide structure) can flow away at the guide structure and out through the cooling channels of the housing component. The coolant flowing out through the cooling channels of the housing component is thus guided to the cooling channels inside the intermediate elements of the brush holder. Finally, the coolant can exit from the cooling channels and reach the shaft in the area of ​​the sliding contacts through the discharge openings of the cooling channels.

[0034] For the motor vehicle specifications according to the present invention, the motor vehicle includes at least one motor according to the present invention. The motor may in particular be a traction motor of the motor vehicle.

[0035] All the advantages and designs described above with respect to the brush holder according to the invention are applicable accordingly to the motor according to the invention, and vice versa. The advantages and designs described with respect to the brush holder and the motor according to the invention are also applicable to the motor vehicle according to the invention, and vice versa. Attached Figure Description

[0036] Other advantages and details of the invention will become apparent from the embodiments described below and from the accompanying drawings. These drawings are schematic illustrations and show:

[0037] Figure 1 An embodiment of a motor vehicle according to the present invention is shown.

[0038] Figure 2 A first embodiment of the brush holder according to the present invention is shown.

[0039] Figure 3 An exploded view of a first embodiment of the brush holder according to the present invention is shown.

[0040] Figure 4 A detailed diagram of the intermediate element according to a first embodiment of the brush holder of the present invention is shown.

[0041] Figure 5 A first embodiment of a motor according to the present invention is shown, which includes a first embodiment of a brush holder according to the present invention.

[0042] Figure 6 A cross-sectional view of a first embodiment of the motor according to the present invention is shown, and

[0043] Figure 7 A cross-sectional view of a second embodiment of the motor is shown, which includes a second embodiment of the brush holder according to the invention. Detailed Implementation

[0044] Figure 1 An embodiment of a motor vehicle 1 according to the present invention is shown. The motor vehicle 1 includes an embodiment of a motor 2 according to the present invention. The motor 2 includes an embodiment of a brush holder 3 according to the present invention.

[0045] Motor 2 is the traction motor of vehicle 1. This traction motor is connected to the traction accumulator 5 of vehicle 1 via power electronics 4. The traction accumulator 5 can be, for example, a high-voltage battery that provides direct current (DC). The DC current can be converted into multiphase, especially three-phase, alternating current by the power electronics 4, which is configured as a particularly bidirectional inverter, for operating motor 2. Conversely, generator operation of motor 2 is also possible, in which the alternating current generated by the motor is converted into DC current by the power electronics 4 and supplied to the accumulator 5.

[0046] Motor 2 is a separately excited machine, specifically a separately excited synchronous motor. Motor 2 includes a rotating shaft 6 that forms a sliding contact with the brush holder 3. The sliding contact allows the rotor coils (not shown) arranged on the rotor to be energized, enabling motor 2 to operate as a motor or generator.

[0047] exist Figure 2 An embodiment of the brush holder 3 is shown. The brush holder 3 includes an intermediate element 7 and two contact elements 8 and 9. The contact elements 8 and 9 are used to electrically contact at least one brush 10, respectively. In this embodiment, the contact elements 8 and 9 are used to contact three brushes 10, respectively.

[0048] Contact elements 8 and 9 are, for example, made of metal plates and are conductive. Intermediate element 7 is electrically insulating and, for example, made of plastic. Intermediate element 7 can be manufactured in one piece, for example, by injection molding, especially in a single mold. Brush 10 is implemented as a carbon brush and has at least a substantially rectangular shape, wherein the side of the brush pointing towards shaft 6 can have a concave bend, which can in particular match the radius of the contact ring of shaft 6.

[0049] Contact elements 8 and 9 are arranged on two opposite sides 11 and 12 of the intermediate element 7. Furthermore, the intermediate element 7 includes a receiving portion 13 in which the rotating shaft 6 of the motor 2 can be received. The first contact element 8 is arranged on the first side 11 of the intermediate element 7. Correspondingly, the second contact element 9 is arranged on the second side 12 of the intermediate element 7. The geometry of the contact element 9 and the arrangement of the brush 10 on the second side 12 of the intermediate element 7 are the same as the geometry of the contact element 8 shown in top view of the first side 11 and the arrangement of the contact element 8 and the brush 10 on the first side 11 of the intermediate element 7.

[0050] Current can be supplied to the first annular contact portion on the shaft 6 via a brush 10 arranged on the first side 11 of the intermediate element 7 and capable of being energized via the first contact element 8. Current can be correspondingly drawn from another annular contact portion arranged axially offset along the shaft 6 via a brush 10 arranged on the second side 12 and contacted via the contact element 9. Reverse current flow can also be achieved. In this way, for example, current can be energized to an excitation coil device arranged on a rotating shaft.

[0051] The receiving portion 13, extending between the opposing sides 11 and 12 of the intermediate element 7, is implemented as a circular through-hole. The intermediate element 7 and the contact elements 8 and 9 are annular discs, allowing the brush 10 to be arranged around the circumference of the rotating shaft 6 via the brush holder 3. Because the receiving portion 13 is constructed as a through-hole, the intermediate element completely surrounds the shaft 6 in a plane perpendicular to the axis of rotation 43 of the shaft 6 or in a plane perpendicular to the axial extension of the shaft 6. Alternatively, the receiving portion 13 may be configured as a recessed portion of the intermediate element 7, such that the intermediate element 7 and / or the contact elements 8 and 9 are, for example, horseshoe-shaped or C-shaped. This also allows the brush 10 to be arranged around the circumference of the rotating shaft 6.

[0052] Contact elements 8 and 9, together with intermediate element 7, define a plurality of receiving sections 14, in which brush 10 is received. Here, the receiving sections 14 are formed by arcuate sections 15 of contact elements 8 and 9, respectively. Thus, a receiving section 14 with a generally rectangular cross-section is formed between the arcuate section 15 and intermediate element 7. Brush 10 is arranged within the receiving section 14.

[0053] The brush 10 is connected to the contact elements 8 and 9 via a connecting device 16. This connecting device 16 can be designed as, for example, a cable, clip, clamp, etc., and enables the brush 10 to be electrically connected to the contact elements 8 and 9. Furthermore, the contact elements 8 and 9 each have contact sections 17 and 18 to achieve electrical contact, which protrude outward from the intermediate element 7 in the radial direction of the through hole 13 or the shaft 6.

[0054] Contact sections 17 and 18 each have at least one opening 19 into which a conductive pin 20 is inserted. Through the conductive pin 20 and contact sections 17 and 18, contact elements 8 and 9 can make electrical contact and, for example, be connected to a circuit for generating the excitation current of the motor 2 via at least one wire. Inserting the pin 20 into the opening 19 allows contact elements 8 and 9 with the same geometry to be manufactured as identical components. By using identical components for contact elements 8 and 9, the manufacturing cost for the brush holder 3 is advantageously reduced.

[0055] The brush holder 3 also includes multiple clamping devices 21, which can apply force to the brushes 10 disposed on the brush holder. Here, the force is directed towards the center of the shaft 6 arranged in the receiving portion 13. The clamping devices 21 are implemented as helical springs and are respectively arranged on the pin-shaped protrusions 22 of the contact elements 8 and 9. The clamping devices 21 are respectively arranged in the receiving section 23 of the intermediate element 7, wherein the outer periphery of the helical spring is surrounded by the arc-shaped protrusion 24 of the intermediate element 7, which protrudes from the side 11 in the axial direction of the shaft 6. In this way, the clamping devices 21 are stably held on the brush holder 3.

[0056] Furthermore, the intermediate element 7 includes three fixing sections 25, each having an opening 26. These openings allow for the guidance of fixing devices 27, such as bolts, to pass through, for example, to secure the brush holder 3 to or within the motor 2. The fixing sections 25 are formed by protrusions 48 protruding from the first side 11 and the second side 12 of the intermediate element 7. These protrusions 48 are constructed individually or integrally with the protrusions 24 defining the receiving section 23.

[0057] exist Figure 3 An exploded view of the brush holder 3 is shown. (Compared to...) Figure 2 Compared to the illustration in the previous version, the brush holder 3 is twisted here, allowing the second side 12 of the intermediate element 7 to be observed. It is evident that the intermediate element 7 has multiple rib structures 28 not only in the first side 11 but also in the second side 12. These rib structures extend in regions of the intermediate element 7 that, together with the arcuate sections 15 of the contact elements 8 and 9, define receiving sections 14. The rib-like structures 28 reduce the contact area between the brush 10 and the intermediate element 7, thereby making it easier for the brush 10 to press against the shaft 6. Furthermore, the rib-like structures 28 allow liquid and / or gaseous coolant to flow through the receiving sections 14.

[0058] Furthermore, a fixing device 27 is shown, which is arranged in the opening 26. The pins 20 engaging in the opening 19 may, for example, have threads for fastening nuts 29 and for connecting one or more cables 30, which may be fastened to the pins 20, for example, via cable terminations 31.

[0059] Furthermore, the intermediate element 7 includes a cooling channel 32 extending therein, which has an inlet opening 33 and a plurality of outlet openings 34, 35. The cooling channel 32 is used to load coolant for the brush 10 and / or the mating parts of the brush 10 in the sliding contact device, as will be described in more detail below.

[0060] The intermediate element 7 also has a plurality of pins 36 protruding from sides 11, 12, each pin extending through a corresponding through-hole 37 in an adjacent contact element 8 or 9. After the contact elements 8, 9 are arranged, the contact elements 8, 9 can be secured to the intermediate element 7 by deforming the pins 36, particularly by widening the section of the pins 36 that extends beyond the through-hole 37. Furthermore, one side of the intermediate element 7, in this embodiment the second side 12, may have one or more slots 49 to predetermine the mounting orientation of the brush holder 3 on the motor 2. Here, the slots 49 may, for example, be constructed in a protrusion 48 on the second side 12.

[0061] exist Figure 4 The diagram shows a top view of the first side 11 of the intermediate element 7. The orientation of the cooling channel 32 within the intermediate element 7 is schematically shown. The cooling channel 32 is tapered, with its wider end located on the outer periphery of the intermediate element 7 and forming a discharge opening 35. The narrower end of the tapered shape leads to a discharge opening 34, which is arranged on sides 11 and 12 of the intermediate element 7 adjacent to the contact area between the brush 10 and the contact ring of the rotating shaft 6.

[0062] The discharge opening 34 is implemented here as a drain hole, so that the liquid coolant supplied to the cooling channel 32 drips from the intermediate element 7 and thus can reach the contact area of ​​the brush 10 and its mating sliding contact device. Cooling of the sliding contact device can be achieved in this way because, for example, oil dripping from the rotating shaft 6 carries away heat from that shaft. Besides in Figure 3 Apart from the entry opening 33 shown, the structure of the first side 11 of the intermediate element 7 corresponds to the structure of the second side 12, thereby enabling the use of contact elements 8 and 9 with the same construction.

[0063] In this embodiment, the intermediate element 7 has three pins 36 for fixing on each side. Furthermore, the intermediate element includes three fixing sections 25 and three receiving sections 23 for retaining the clamping device 21. Here, each pair of receiving sections 23 is paired with one fixing section 25 by a common protrusion structure, which is formed in one piece by protrusions 24 and 48. The third receiving section 23 and the third fixing section 25 are formed by separate protrusions 24 or 48 projecting from the first or second surface 12. Obviously, additional rib structures 38 also extend in the region below the contact elements 8, 9 to allow the contact elements 8, 9 to rest flat and / or stress-free against the intermediate element 7.

[0064] exist Figure 5 An embodiment of the motor 2 is shown. The motor 2 includes the aforementioned embodiment of the brush holder 3. The brush holder 3 is shown here in partial cross-section, so that the cooling channel 32 extending inside the intermediate element 7 can be seen.

[0065] The brush holder 3 is arranged in a wet cavity of the motor 2, which is at least partially filled with electrically insulating coolant. The intermediate element 7 of the brush holder is partially abutted with its first side 11 against the housing component 39 of the motor 2, which is constructed as an end cap and is specifically used to support a rotating shaft 6 (not shown here) inside the housing of the motor 2.

[0066] Coolant can be supplied to the cooling passage 32 of the intermediate element 7 via a cooling passage 40 extending inside the housing component 39. The coolant can be, in particular, an electrically insulating cooling oil used to cool the rotor and / or stator of the motor 2. Figure 5 In the diagram, the rotor is located on the left side of the housing component 39 and therefore on the side of the housing component 39 opposite to the brush holder 3. The housing component 39 is thus arranged between the rotor of the motor 2 and the brush holder 3.

[0067] Coolant can be supplied to the cooling channel 40 of the housing component 39 via at least one guide structure 41. The guide structure 41, for example implemented as a baffle, can collect the cooling oil thrown out inside the motor 2 during rotor rotation, wherein the cooling oil can be discharged at the guide structure 41 in accordance with the drawn arrow, thereby supplying cooling oil to the cooling channel 40.

[0068] exist Figure 6 A cross-sectional view of a first embodiment of the motor 2 is shown. It can be seen that the cooling channel 40 is directly connected to the guide structure 41. Coolant can be supplied via the cooling channel 40 through the inlet opening 33 to the cooling channel 32 inside the intermediate element 7 of the brush holder 3. The cooling channel 32 includes a first section 42 that extends at least substantially parallel to the axis of rotation 43 of the rotating shaft 6. Section 42 leads to another section 44, which extends radially relative to the axis of rotation 43. In the region of the receiving portion 13, this other section 44 leads to another axial section 45 through which coolant can be supplied to the outlet opening 34 at opposite sides 11, 12 of the intermediate element 7. Coolant is supplied to the sliding contact device through the outlet opening 34, and then flows from the sliding contact device, for example, into a coolant trough. The coolant can then be resupplied from the coolant trough to the rotor of the motor 2. The outlet opening 35 serves, for example, for ventilation of the cooling channel 32.

[0069] exist Figure 7A second embodiment of the motor 2 is shown. This second embodiment includes a second embodiment of the brush holder 3. The difference between the second embodiment of the brush holder 3 and the first embodiment of the brush holder 3 lies in the orientation of the cooling channel 32 inside the intermediate element 7. The coolant supply on the motor side is achieved in a manner similar to the first embodiment of the motor 2 via the guide structure 41 and the cooling channel 40 through the housing component 39. A section 42 of the cooling channel 32 connects to an inlet opening 33 on the second side 12 of the intermediate element 7. This section extends centrally into two sections 46 and 47 inside the intermediate element 7, which extend obliquely in the radial direction and terminate at a discharge opening 34 in the region of the receiving portion 13.

[0070] In addition to the embodiment where the discharge opening 34 is configured as a drain hole, the discharge opening 34 can also be configured as a nozzle. Here, coolant can be delivered to the cooling channel 32 inside the intermediate element 7 using pressure, so that coolant can be sprayed from the discharge opening 34 configured as a nozzle onto the brush 10 and / or the contact area between the brush and its mating member in the sliding contact device.

Claims

1. A brush holder for holding at least two brushes (10) of a sliding contact device, the brush holder comprising an intermediate element (7) and two contact elements (8, 9) for electrically contacting at least one of the brushes (10), wherein, The contact elements (8, 9) are arranged on opposite sides (11, 12) of the intermediate element (7), wherein a first contact element (8) is arranged on a first side (11) of the intermediate element for electrically contacting at least one first brush and a second contact element (9) is arranged on a second side (12) of the intermediate element for electrically contacting at least one second brush, the intermediate element (7) having a receiving portion (13) for the rotary shaft (6) extending through the opposite sides (11, 12), the intermediate element (7) and the two contact elements (8, 9) being configured for supporting the first and second brushes spaced apart in the axial direction of the rotary shaft.

2. The brush holder according to claim 1, characterized in that the receiving portion (13) is configured as a through-hole or a recess of the intermediate element (7).

3. The brush holder according to claim 1 or 2, characterized in that the intermediate element (7) and / or the contact elements (8, 9) are ring- shaped discs.

4. The brush holder according to claim 1 or 2, characterized in that the contact elements (8, 9) each define at least one receiving section (14) for receiving one of the brushes (10) together with the intermediate element (7).

5. The brush holder according to claim 4, characterized in that the areas on the two sides (11, 12) of the intermediate element (7) that define the receiving sections (14) each have a rib structure (28).

6. The brush holder according to claim 1 or 2, characterized in that the contact elements (8, 9) each have at least one contact section (17, 18) that projects laterally beyond the intermediate element (7).

7. The brush holder according to claim 1 or 2, characterized in that the contact elements (8, 9) have the same geometry.

8. The brush holder according to claim 1 or 2, characterized in that the intermediate element (7) has at least one cooling channel (32) that extends inside the intermediate element (7).

9. The brush holder according to claim 8, characterized in that the intermediate element (7) has at least one discharge opening (34) of the cooling channel (32) on at least one of the opposite sides (11, 12).

10. The brush holder according to claim 9, characterized in that the discharge opening (34) is configured as a leak hole or as a nozzle.

11. The brush holder according to claim 1 or 2, characterized in that the brush holder comprises at least one pressing device (21), wherein a force can be applied to the brushes (10) arranged on the brush holder (3) by means of the pressing device (21).

12. The brush holder of claim 11, wherein A force can be applied to the brushes (10) arranged on the brush holder (3) by means of the pressing device (21) in the direction of the center of the shaft (6) arranged in the receiving portion.

13. The brush holder according to claim 1 or 2, characterized in that The intermediate element (7) has at least one pin (36) extending from each of the two opposite sides (11, 12) respectively, which pin extends through a corresponding through-hole (37) in the adjacent contact element (8, 9) The contact elements (8, 9) are fixed to the intermediate element (7) by deforming the pins (36) respectively.

14. An electric machine comprising at least one brush carrier (3) according to any one of claims 1 to 13.

15. The electric machine of claim 14, wherein, The brush carrier (3) is arranged in a wet cavity of the electric machine (2) which is at least partially filled with an insulating coolant.

16. The electric machine according to claim 14 or 15, characterized in that The intermediate element (7) of the brush carrier (3) has at least one cooling channel (32) extending inside the intermediate element (7), wherein the intermediate element (7) is attached to a housing part (39) of the electric machine (2) through which a cooling channel (40) of the housing part (39) can supply coolant to the cooling channel (32) of the intermediate element (7).

17. The electric machine of claim 16, wherein, The housing part (39) is an end cap.

18. The electric machine according to claim 16, characterized in that The housing part (39) is arranged between a rotor of the electric machine (2) and the brush carrier (3), wherein coolant liquid thrown against at least one guide structure (41) when the rotor is rotating can be supplied as coolant to the cooling channel (40) of the housing part (39) through the guide structure (41).

19. A motor vehicle comprising at least one electric machine (2) according to any one of claims 14 to 18.

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