Insulating Electrical Coupler

Abstract

Generally speaking, aspects of the present application relate to mitigating induced voltages in rotor components of an electric motor. Illustratively, one or more aspects relate to incorporating one or more electrical isolation elements to insulate the rotor from the remaining components of the electric motor. The electrical isolation elements are incorporated into a coupler arrangement between the rotor and the stator. Through the isolation, the induced voltages cannot discharge through the gears and bearings. Illustratively, the isolation coupler is located on or proximate to the centerline of the rotor shaft to provide torque transfer.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims priority to U.S. Provisional Application No. 63 / 284,555, entitled "ISOLATED ELECTRIC COUPLER," filed November 30, 2021. U.S. Provisional Application No. 63 / 284,555 is incorporated by reference herein in its entirety. [Background technology]

[0002] Generally, various vehicles, such as electric vehicles, internal combustion engine vehicles, hybrid vehicles, etc., may be configured with various components to assist in the operation of the vehicle. Traditionally, many components are specifically configured according to specifications necessary to implement a specified function. For example, attributes (e.g., materials, dimensions, mounting) of structural components within a vehicle are specified and selected to meet or exceed the loads imposed on the structural components.

[0003] Electric motors are widely used in various industrial and domestic applications. Generally, this type of motor includes a laminated magnetic core attached to a drive shaft. Electric motors usually include a rotating component, a rotor, whose rotation is due to the interaction of windings with a magnetic field that generates a torque about the axis of the rotor. Laminated cores can be manufactured from multiple laminated magnetic disks or multiple arc-shaped core segments. Laminated cores include multiple longitudinal slots into which conductive metal bars or wires are fitted. Both ends of the bars extend beyond either end of the laminated core. End rings or end caps at either end of the laminated core are used to mechanically and electrically couple the ends of the rotor bars. The stator is the part of an electric motor and is the stationary part of the rotating system that converts the rotating magnetic field into electric current. [Brief description of the drawings]

[0004] The present disclosure is described herein with reference to drawings of certain embodiments, which are intended to be illustrative and not limiting of the disclosure. It is to be understood that the accompanying drawings, which are incorporated in and constitute a part of this specification, are for the purpose of illustrating the concepts disclosed herein and may not be to scale.

[0005] [Figure 1] FIG. 1 is a block diagram illustrating an embodiment of an electric vehicle that may be used in accordance with exemplary embodiments of the present application.

[0006] [Diagram 2] FIG. 2 is a cross-sectional view of a drive motor and gearbox configured for use in accordance with an exemplary embodiment of the present application.

[0007] [Figure 3A] FIG. 2 is a perspective view of an input gear having an isolation coupler formed in accordance with an exemplary embodiment of the present application.

[0008] [Figure 3B] FIG. 13 is a perspective view of an insulating element for use in an exemplary embodiment of an input gear;

[0009] [Figure 3C] FIG. 1 illustrates a perspective view of an input gear having an insulating coupler including six insulating elements according to an exemplary embodiment of the present application;

[0010] [Figure 3D] FIG. 13 is a perspective view of a retainer that helps hold the insulating element 110 in the input gear.

[0011] [Figure 4] FIG. 1 is a perspective view of a portion of an electric motor including a rotor for use in combination with an exemplary input gear.

[0012] [Diagram 5] FIG. 13 is an exploded perspective view of an alternative embodiment of an input gear and a portion of a rotor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Generally, one or more aspects of the present disclosure relate to managing electrically induced damage in vehicle components. Specifically, aspects of the present disclosure relate to mitigating induced voltages in rotor components of an electric motor. Illustratively, one or more aspects relate to incorporating one or more electrical isolation elements to insulate the rotor from the remaining components of the electric motor. The electrical isolation elements are incorporated into a coupler arrangement between the rotor and the stator. Through the isolation, the induced voltages cannot discharge through the gears and bearings. Illustratively, the isolation coupler is located on or proximate to the centerline of the rotor shaft to provide torque transfer.

[0014] Typical solutions to Electrical Electrical Bearing Damage (EIBD) include incorporating a stable ground solution from the rotor to the chassis ground. For example, some electric motors may include carbon / silver brushes or similar solutions that attempt to act as a stable ground. These have the drawback of being highly resistive and having a limited lifespan, which can be a drawback especially in long-term implementations such as semi-trucks. Another solution to EIBD is the use of common mode chokes, which act as electrical filters to block high frequency signals such as those generated by the operation of an electric motor. Common mode choke solutions can involve nanocrystalline or ferrite cores that surround the three phase motor leads to suppress common mode overshoot voltages. Common mode choke solutions are typically expensive and difficult to package. They are also limited in their effectiveness as they cannot completely mitigate discharges. These and other typical solutions may be even more inadequate in electric vehicle implementations where the common mode voltage scales with the input voltage.

[0015] FIG. 1 illustrates an embodiment of an electric vehicle 10. The embodiment of the electric vehicle 10 includes a battery 16, an electronic device 18, a first drive motor 12A, a first gearbox 14A, a second drive unit 14B, and a second gearbox 14B. The electric vehicle may be controlled by the electronic device 18. The battery 16 may power the first drive motor 12A, the second drive motor 12B, or both. The first drive motor 12A and the second drive motor 12B may be electric motors. The first drive motor 12A may be connected to the first drive unit 14A, and the connection may be an electrically isolated connection. The second drive motor 12B may be connected to the second drive unit 14A, and the connection may be an electrically isolated connection. The first drive motor 12A may be connected to the first drive unit 14A via an isolation coupler, and the isolation coupler may be a separate component or may be part of the drive unit 14A. The first drive motor 12A or the second drive motor 12B can generate a force, which can be a rotational force. This force can be applied to the wheels 20 directly via the first drive motor 12A, indirectly via the first gearbox 14A, indirectly, or through some combination. This force can be applied to the wheels 20 directly via the second drive motor 12A, indirectly via the second gearbox 14B, indirectly, or through some combination.

[0016] FIG. 2 illustrates a cross-sectional view of one embodiment of the drive motor 12A, the drive motor 12B, and the gearbox 14A, the gearbox 14B. In this embodiment, the drive motor is an electric motor, but the system can be other types of motors, such as combustion type. The drive motor 12A, the drive motor 12B, and the gearbox 14A, the gearbox 14B can be integrated or separate. In this embodiment, the drive motor 12A is coupled to an input gear 100 that is coupled to the gearbox 14A. The drive motor 12A can include a stator 150 and a rotor 200. The rotor 200 can include a connector portion 202. The connector portion 202 in this embodiment is located at one end of the rotor 200, but the connector portion can be located at either or both ends of the rotor. The connector portion 202 includes a groove 204. The groove 204 can be cylindrical as in this embodiment. It will be understood that the groove 204 can be other shapes, such as square, rectangular, or spherical. Additionally, the groove 204 may be a plus shape or any shape other than those mentioned above that allows for engagement of the insulating element 110 .

[0017] The connector portion 202 of the rotor 200 is connected to the connector portion 104 of the input gear 100. The connection between the connector portion 202 and the connector portion 104 is made with an insulating element 110. The insulating element 110 engages both the rotor connector portion 202 and the input gear connector portion 104. The input gear connector portion 104 includes a number of grooves 108. The grooves 108 may be cylindrical in shape, or may be rectangular, square, spherical, or other shapes that can engage with the insulating element 110. The grooves 108 and 204 may be shaped the same as the insulating element 110 such that the insulating element 310 fits within the grooves 108 and 204. The input gear 100 may include a first bearing interface 116, a second bearing interface 118, and a gear portion 120. The gear portion 120 of the input gear 100 may engage with a vehicle rotor or gearbox 14A. While the gear portion 120 in this embodiment is a gear, the gear portion 120 may be any type of connection that allows for the transfer of power from the input gear 100 to the gearbox 14A. The gearbox 14A may be any component that allows for the transfer of power from the drive motor 14A to the wheels. In this embodiment, the drive motor 14A includes a rotor interface 230.

[0018] 3A illustrates a simplified block diagram of a perspective view of an input gear 100 having an isolation coupler formed in accordance with an exemplary embodiment of the present application. As illustrated in FIG. 3A, the input gear 100 includes a rotor portion 102 that operates in conjunction with a rotor component in an electric motor. As explained, rotation of the rotor can in turn rotate the input gear 100, via a physical connection between the rotor and the input gear 100, which has an additional gear portion 120 for use in operating an electric motor, such as an electric vehicle.

[0019] The input gear 100 may include a connector portion 104 perpendicular to the axis of rotation 106 of the input gear 100. The connector portion 104 may be of various lengths as a function of the torque experienced, materials utilized, etc., or based on the characteristics of the rotor components. Illustratively, in one embodiment, the connector portion 104 may include a plurality of cylindrically shaped grooves 108 for receiving one or more insulating elements 110 (shown in FIG. 3B). The grooves 108 of the connector portion 104 may be manufactured via a manufacturing process including machining, grinding, or other similar techniques. Although the grooves 108 are illustrated as having a cylindrical shape for receiving insulating elements of the same or similar shape, in other embodiments, the grooves 108 may have different shape characteristics. Additionally, in some embodiments, the grooves 108 may incorporate insulating elements 110 that may not have a uniform shape (e.g., a first portion of the insulating element having a first shape and a second portion of the insulating element having a different second shape).

[0020] The insulating element 110 illustrated in FIG. 3B may generally be considered a roller bearing. The insulating element 110 may be constructed from one of a variety of materials, such as ceramic, plastic, or a variety of other non-conductive materials. The dimensions of the insulating element, such as length and diameter, may be selected depending on the torque, the number of insulating elements in the connector, and the like. The insulating element 110 may have a relatively smooth outer surface. Additionally, in some embodiments, the insulating element may include notches, protrusions, chamfered edges, and the like to aid in placement, mounting, or retention in the groove 108 (FIG. 3A).

[0021] Returning to FIG. 3C, in one embodiment, the rotor portion 102 of the input gear 100 illustratively includes six insulating elements 110 (illustrated as 110A, 110B, 110C) spaced equidistantly about the axis of the input gear 100. In other embodiments, the connector portion 104 may include a different number of insulating elements 110. In other embodiments, the insulating elements 110 may be non-equidistantly spaced about the connector portion 104 or embodied in various shapes. Additionally, the input gear 100 may include bearings or non-conductive spacers 112 to withstand axial loads presented to / by the input gear. The input gear 100 may also include a retainer 114 to help retain the insulating elements 110 within the connector portion 104. The retainer 114 shown in FIG. 3D may be optional. As illustrated in FIG. 3D, the retainer may include a number of openings 117 corresponding to the placement of the insulating elements 110. The opening 117 can be configured to interface with the illustrated element 110 for retaining the insulating element, including but not limited to pressing against a surface of the insulating element, bonding to a portion of the insulating element, interfacing with a complementary protrusion or gap, etc. The retainer 114 can be attached to the input gear 100 by adhesive, tension, soldering, and any number of additional attachment mechanisms.

[0022] With reference to FIG. 4, an electric motor 12 including a rotor 200 for use in combination with an exemplary input gear 100 is described. The electric motor 12A includes a group of electromagnets centered on the rotor 200, with the poles facing the stator poles. Typically, the rotor 200 is positioned inside the stator to cause the rotor to rotate about its axis. Alternatively, the rotor 200 can be considered a cantilevered rotor. The electric motor 12A, or rotor 200, can include a variety of materials, such as aluminum bars, steel laminations, magnets, etc., to cause induced current flow from the stator components or magnetic fields. As applied to the present application, the rotor 200 can include a connector portion 202, which is illustratively complementary, at least in part, to the connector portion 104 of the input gear 100. Specifically, the connector portion 202 of the rotor 200 can include a set of grooves 204 that directly correspond to the insulating element 110 and the connector portion 104 of the input gear 100. The rotor 200 may illustratively engage the input gear 100 based on the engagement of the isolation element 110 with both the rotor and the input gear. However, the rotor 200 and the input gear 100 remain electrically isolated due to the non-conductive characteristics of the selected isolation element 110. As noted above, the grooves 204 may be manufactured by a variety of manufacturing processes, including, but not limited to, machining, grinding, or other similar techniques.

[0023] 5 corresponds to an alternative embodiment of an input gear 302 and a portion of a rotor 322. The input gear 302 includes a connector portion 304 that extends into a set of cutouts 306. Generally, the cutouts 306 are shaped to receive a plurality of cylindrically shaped insulating elements 310. The cutouts 306 may be formed by machining or grinding. The input gear 302 also includes an outer collar 308 for retaining at least the insulating elements 310. Illustratively, the connector portion 304 may be precision ground on its outer diameter (to improve coupler clearance) when mated with the collar 308. Such techniques may include machining, grinding (e.g., spline grinding or worm grinding), and the like.

[0024] Additionally, the preferred rotor 322 also includes a number of grooves 324 for receiving the insulating elements 310. The grooves 324 can be manufactured using techniques such as machining, grinding (e.g., spline grinding, or worm grinding). Additionally, the rotor 322 can also include a snap ring 326 or shoulder for applying an axial load to the insulating elements. The insulating elements 110 can be constructed from one of a variety of materials, such as ceramic, plastic, or a variety of other non-conductive materials. The dimensions of the insulating elements, such as length and diameter, can be selected depending on the torque, the number of insulating elements in the connector, and the like. As illustrated in FIG. 5, in one embodiment, six insulating elements 310 are equidistantly spaced about the axis of the input gear 302 and the rotor 322. In other embodiments, the insulating elements 310 can be non-equidistantly spaced about the connector portion 304 or embodied in various shapes. Additionally, the number of insulating elements 310 can vary.

[0025] In the above specification, the disclosure has been described with reference to certain embodiments. However, as will be appreciated by those skilled in the art, the various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the disclosure. Thus, this specification is considered to be illustrative and is intended to teach those skilled in the art how to make and use the various embodiments of the disclosed vent assembly. It should be understood that the forms of the disclosure shown and described herein are to be taken as representative embodiments. Equivalent elements, materials, processes, or steps may be substituted for those typically shown and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, as will be apparent to those skilled in the art after having the benefit of this specification, all of which are incorporated herein. The terms "including," "comprising," "incorporating," "consisting of," "have," "is," and the like, used to describe and claim the disclosure, are intended to be construed in a non-exclusive manner, i.e., allowing for the presence of items, components, or elements not expressly recited. Additionally, references to the singular are also to be construed as references to the plural.

[0026] Furthermore, the various embodiments disclosed herein are to be taken in an illustrative and descriptive sense, and should not be construed as limiting the present disclosure in any way. Any references to joints (e.g., attached, affixed, coupled, connected, etc.) are merely used to aid the reader in understanding the present disclosure, and may not create limitations on the position, orientation, or use of the systems and / or methods disclosed herein, among other things. Thus, any references to joints, if any, should be interpreted broadly. Moreover, such references to joints do not necessarily imply that two elements are directly connected to each other.

[0027] Additionally, all numerical terms, such as, but not limited to, "first," "second," "third," "primary," "secondary," "main," or any other standard terminology and / or numerical terms, should be viewed merely as identifiers aiding the reader's understanding of the various elements, embodiments, variations, and / or modifications of the present disclosure, and in particular may not create any limitation as to the order or priority of any element, embodiment, variation, and / or modification in relation to or relative to another element, embodiment, variation, and / or modification.

[0028] It will also be understood that one or more of the elements depicted in the drawings / figures may be implemented in a more separated or integrated manner, or may be removed or rendered inoperative in certain cases, as may be useful depending on the particular application.

Claims

1. an input gear including an input gear connector portion, the input gear connector portion extending into a plurality of cutouts in the input gear; a rotor including a rotor connector portion; a plurality of insulating elements disposed between the input gear connector portion and the rotor connector portion, the insulating elements configured to connect the input gear connector portion and the rotor connector portion; the cutouts are configured to receive the plurality of insulating elements; an electrically isolating coupler, wherein the input gear and the rotor are electronically isolated;

2. An electrical isolation coupler as described in claim 1, wherein an outer collar is positioned around the cutout to retain the insulating element.

3. 10. The electrical isolation coupler of claim 1, wherein each of the plurality of insulating elements is cylindrical in shape.

4. 10. The electrically isolating coupler of claim 1, further comprising a non-conductive spacer attached to the input gear connector portion, the non-conductive spacer being attached between the plurality of insulating elements and an end of the input gear connector portion and configured to withstand axial loads imparted to and / or by the coupler.

5. 2. The electrically isolating coupler of claim 1, wherein at least one of the input gear connector portion or the rotor connector portion encompasses the other.

6. 2. The electrical isolation coupler of claim 1, wherein the rotor further includes a stop element, the stop element configured to withstand an axial load of the plurality of isolation elements.

7. 2. The electrically isolating coupler of claim 1, wherein the plurality of insulating elements are equidistantly spaced about an axis of the coupler.

8. An electrical isolation coupler as described in any one of claims 1 to 7, wherein the plurality of insulating elements are formed from at least one material of plastic or ceramic.

9. An electrical insulating coupler as described in any one of claims 1 to 7, wherein the rotor connector portion includes a plurality of grooves for receiving the plurality of insulating elements.

10. An electrically insulating coupler as described in any one of claims 1 to 7, wherein the input gear connector portion includes a first axis, the rotor connector portion includes a second axis, and the first axis is substantially coincident with the second axis.

11. An electrically insulating coupler as described in claim 10, wherein the connection between the input gear connector portion and the rotor connector portion is configured to allow movement of the input gear along the first axis and movement of the rotor along the second axis.

12. An electrically insulating coupler as described in claim 10, wherein the input gear connector portion at least partially surrounds the rotor connector portion.

13. An electrically insulating coupler as described in claim 10, wherein the connection between the input gear connector portion and the rotor connector portion is configured to transmit rotational force between the input gear connector portion and the rotor connector portion.

14. An electrical isolation system comprising an electrical isolation coupler described in any one of claims 1 to 7 and an electric motor.

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