A support

Abstract

The invention relates to a support for carrying an element in a motor. The support comprises a leadframe holder portion and a terminal block portion. The leadframe holder portion comprises a circumferential frame extending around a frame axis and at least one leadframe guide to carry a stator leadframe. The terminal block portion extends from the leadframe holder radially away from the frame axis and comprises at least one terminal region. The, or each, terminal region including a securing element carrier arranged such that a stator leadframe connector and an external connector can be arranged in a terminal region and be secured to one another using a securing element arranged in the securing element carrier. Wherein the leadframe holder portion and terminal block portion are formed as a single component.

Description

[0001] A Support

[0002] The invention relates to a support for carrying elements in an electric motor or generator, particularly to a support that comprises a leadframe carrier with an integrated terminal block. The invention extends to a motor assembly comprising such a support and to a method of assembling such a motor assembly.

[0003] Electrical motors and generators may include a stator that is mounted inside a housing and a rotor that is supported for rotation relative to the stator. The rotor may include a shaft, and a set of permanent magnets mounted to the shaft. The stator may include a motor casing and coils which may be wound around parts of the stator. The rotor shaft may be arranged such that the rotor can rotate relative to the casing and stator, and such that the stator coils surround the set of permanent magnets mounted to the shaft. The stator receives the rotor such that the two structures can magnetically interact to create motion when an electric current passes through the windings.

[0004] During assembly of a motor, it may be necessary to electrically connect the coils of the stator to external electrical connections, for example a power supply, or motor controller. Such connections may be made at a terminal block, with leadframes connecting coils of the stator to the terminal block.

[0005] The invention provides a support for carrying elements in a motor, the support comprising a leadframe holder portion and a terminal block portion;

[0006] the leadframe holder portion comprising a circumferential frame extending around a frame axis and comprising at least one leadframe guide to carry a stator leadframe;

[0007] the terminal block portion extending from the leadframe holder radially away from the frame axis and comprising at least one terminal region, the, or each, terminal region including a securing element carrier arranged such that a stator leadframe connector and an external connector can be arranged in a terminal region and be secured to one another using a securing element arranged in the securing element carrier; and

[0008] wherein the leadframe holder portion and terminal block portion are formed as a single component.

[0009] By integrally forming the leadframe holder with the terminal block several advantages are realised, and these include:a reduction in the total part count for a motor assembly;

[0010] facilitating assembly as the parts cannot separate unintentionally;

[0011] facilitating alignment of parts during assembly; and

[0012] reducing the volume of material required to manufacture the components.

[0013] Some of these advantages will be discussed in more detail below.

[0014] The support is to carry one or more elements in a motor or a generator. The element, or elements, to be carried include one or more stator leadframes. A stator leadframe is to carry electrical power from a terminal block to a stator winding. The support may be configured to carry other elements in addition to a stator leadframe.

[0015] The support comprises two major portions, a leadframe holder portion and a terminal block portion. The leadframe holder portion includes at least one leadframe guide to carry a stator leadframe. The terminal block portion is a portion of the support that is to provide a terminal region for connecting a part of a stator leadframe to an external connector.

[0016] The circumferential frame is a part of the support portion and may be any suitable shape. The circumferential frame extends around the frame axis and may be continuous or may include at least one discontinuity or break. When assembled into a motor or generator, the frame axis may be substantially coaxial with an axis of a stator to which the support is attached. The axis of the stator may be coaxial with an axis of a rotor of the motor.

[0017] The leadframe guide may be in any suitable form, for example a leadframe guide may comprise a clip, groove, projection, recess, or any other feature that can support and I or guide a stator leadframe.

[0018] The terminal block portion comprises at least one terminal region within which a stator leadframe can be connected to an external connector and secured to the terminal block portion using a securing element. Securing the external connector and stator leadframe to the terminal block portion may comprise coupling a fastener, such as a threaded bolt or screw, to a securing element, such as a threaded insert, located in the securing element carrier. The securing element carrier may take any suitable shape or form to carry or locate a securing element. For example, the securing element carrier be a slot into which a securing element can be inserted, or the securing element may be moulded into the support in the securing element carrier.The external connector to which the stator leadframe is to be connected may be an electrical connector to an external component, which may be a component that is not within the motor. The external component may be a controller, or a power supply.

[0019] The leadframe holder portion and terminal block portion are formed as a single component and may be formed by any suitable manufacturing process. For example, the component may be formed by injection moulding, compression moulding, additive manufacturing, such as 3D printing, or it may be milled from a block of material. The component may be formed from an insulating material such as a plastic material. The support may be moulded from a plastic material.

[0020] The circumferential frame may extend continuously around the frame axis. This may provide a more robust frame which may provide a greater resistance to deformation, particularly radial deformation, and this may facilitate assembly. The circumferential frame may be substantially annular such that there is a portion of the circumferential frame that entirely surrounds the frame axis at a substantially consistent radius from said frame axis.

[0021] The at least one leadframe guide may comprise a groove in the circumferential frame into which a portion of the stator leadframe can be inserted. The leadframe guide may be formed in one face of the circumferential frame. The circumferential frame may include at least three leadframe guides, each leadframe guide to carry a stator leadframe. Each of the three leadframe guides may comprise a groove. The groves may extend substantially circumferentially at a substantially fixed radial distance from the frame axis. Each of the grooves may be located at a different radial distance from the frame axis.

[0022] The circumferential frame may include means for fixing the circumferential frame relative to windings of a stator, for example by fixing the support to a part of a stator body or motor housing, for example fixing the support to windings of a stator. The means for fixing the circumferential frame to a motor housing may comprise integral clips or projections. The means for fixing the circumferential frame may comprise at least one axial fixing hole, for example at least 3 axial fixing holes, through which a fixing element or fastener, such as a threaded screw or bolt, can be inserted to secure the circumferential frame, and thereby the support, to a motor housing or to a stator component.

[0023] The, or each, securing element carrier of the terminal region may comprise a threaded insert to accept a threaded fastener, for example a securing bolt or screw. The securing elementmay be held in place in the securing element carrier by any suitable means, for example it may be held in place using friction, clips, adhesive or other means. The threaded insert may be moulded, for example overmoulded or insert moulded, into the securing element carrier. This may facilitate assembly as a securing element does not need to be arranged in the securing element carrier.

[0024] The terminal block portion may comprise a plurality of terminal regions, for example the terminal block portion may comprise three terminal regions. The plurality of terminal regions may be arranged in any suitable way, for example they may be arranged in a line. There may be three terminal regions, and they may be arranged in a line and may be substantially evenly spaced along the line in the terminal block portion. The line along which the terminal regions are arranged may extend substantially perpendicular to the frame axis and may be parallel to a tangent of the circumferential frame.

[0025] The terminal block portion may include void regions between the terminal regions. Void regions may comprise no material and this may assist in the electrical isolation the terminal regions from one another. The inclusion of void regions may reduce the amount of material in the terminal block portion. Voids between the terminal regions may increase the length of a creepage path between the terminal regions.

[0026] The terminal block portion may be spaced from the circumferential frame in the radial or axial direction and may be coupled thereto by any suitable construction, for example one or more beams or plates. One or more terminal regions may be connected to the circumferential frame by one or more radial beams which extend from the terminal region to the circumferential frame. A beam is an elongate structural element. The radial beams may extend along a radial line from the shaft axis and may not be parallel thereto. Terminal regions may be connected to one another by one or more terminal beams. Terminal beams may extend substantially circumferentially around the shaft axis or may extend substantially parallel to the line along which the terminal regions are arranged.

[0027] The pattern of terminal beams, radial beams and voids may be selected to ensure sufficient structural robustness to allow assembly and / or the securing of external connectors to the terminal regions without undue deformation.

[0028] The terminal block portion may comprise side guards which extend axially from circumferential ends of the terminal block portion. Side guards may extend beyond anexternal connection connected to the terminal region. This may enhance electrical isolation of the terminal block portion from the motor housing after assembly and may assist with the rotational alignment of the support about the axis during assembly.

[0029] The invention also provides a motor assembly, the motor assembly comprising a stator body, motor housing, support, at least one leadframe, a securing element, a fastener, and an external connector, the support being as described above, in which:

[0030] the stator body is arranged within the motor housing and the support is arranged at an end thereof;

[0031] the support carries the at least one leadframe so that the at least one leadframe extends from a terminal region of the terminal block portion to a connector of the stator; the securing element is arranged in the securing element holder of the terminal region; and

[0032] the fastener engages with the securing element to secure the leadframe and external connector together in the terminal region.

[0033] The motor housing is to contain and I or align components of a motor. The motor housing may include a recessed region to receive the terminal block portion of the support. This may help with the rotational alignment of the support and any attached components during assembly of the motor.

[0034] The motor assembly method may comprise:

[0035] fixing the support to the stator to form a stator assembly;

[0036] installing at least one stator leadframe into the leadframe guide of the support so that the at least one leadframe extends from a terminal region of the terminal block portion to a connector of the stator;

[0037] arranging the stator assembly within the motor housing; and

[0038] arranging an external connector in the terminal region and using a fastener to engage a securing element arranged in the securing element holder to secure the leadframe and external connector together in the terminal region.

[0039] It should be noted that the order of the steps of installing a leadframe and arranging the stator assembly within the motor housing could be reversed so that the leadframes are installed into the circumferential frame once the stator assembly is fitted into the motor housing.Arranging the stator assembly within the motor housing may comprise aligning the terminal block portion with a recess of the motor housing.

[0040] The order of the steps in the method can be carried out in any practical order, for example the stator leadframes could be installed after the stator assembly is installed in the motor housing.The invention will now be described by way of example only with reference to the following figures in which:

[0041] Figure 1 shows a support for carrying an element in a motor;

[0042] Figure 2 shows the support of Figure 1 with stator leadframes;

[0043] Figure 3 shows a stator assembly;

[0044] Figure 4 shows a motor assembly; and

[0045] Figure 5 shows a flowchart of an assembly method.

[0046] Figure 1 shows a support 1 for carrying an element in a motor. The support 1 comprises a leadframe holder portion 2 and a terminal block portion 4.

[0047] The leadframe holder portion 2 comprises a circumferential frame 6 which, in this example, extends continuously around a frame axis 8. The circumferential frame 6 is substantially annular and extends around the frame axis 8 in a plane substantially perpendicular to the frame axis 8. The circumferential frame 6 has a substantially constant radius R from the frame axis 8.

[0048] The circumferential frame 6 comprises leadframe guides 10, in this case grooves 12 into which a portion of a stator leadframe (shown in Figure 2) can be inserted so that the leadframe guide supports and guides the stator leadframe. In this example there are three leadframe guides 10 which comprise grooves 12 which extend circumferentially around the circumferential frame 6, each leadframe guide 10 comprises a groove 12 at a different radius R from the frame axis 8.

[0049] The terminal block portion 4 extends from the leadframe holder 2 radially away from the frame axis 8 and comprises at least one terminal region 14. In this case the terminal block portion 4 comprises three terminal regions 14. Each terminal region 14 includes a securing element carrier 16 to hold a securing element 18. In this case the securing element 18 is a metal threaded insert to receive a threaded bolt and the securing element 18 is held within a slot in the securing element carrier 16.The securing element carrier 16 is arranged such that a stator leadframe connector and an external connector can be arranged in a terminal region 14 and be secured to one another using the securing element 18, for example by using a threaded bolt.

[0050] The leadframe holder portion 2 and terminal block portion 4 are moulded from plastic as a single component.

[0051] The circumferential frame 6 includes means for fixing the circumferential frame 6 to a part of a stator body to fix the circumferential frame relative to windings of the stator.. In this example, the means for fixing the circumferential frame 6 to a motor housing comprise three axial fixing holes 20 through which a fixing element can be inserted to secure the circumferential frame 6, and thereby the support 1, to a motor housing or stator component (see Figure 4).

[0052] The terminal block portion 4 includes void regions 22 comprising no material between the terminal regions 14.

[0053] The terminal block portion 4 is spaced from the circumferential frame 6 in the radial direction and is coupled thereto by a plurality of radial beams 24 which extend from the terminal region 14 to the circumferential frame 6. The radial beams 24 may extend along a radial line from the shaft axis 8. Terminal regions 14 are be connected to one another by terminal beams 28.

[0054] The terminal block portion 4 comprises side guards 26 which extend axially from circumferential ends 30 of the terminal block portion 4. Side guards 26 extend axially from the terminal portion 4 so that they extend beyond an external connection connected to the terminal region 14.

[0055] Figure 2 shows the support 1 of Figure 1 with stator leadframes 32 arranged in the grooves 12 of the circumferential frame 6. Each stator leadframe 32 includes four winding connectors 34 to connect the stator leadframe 32 to windings of a stator body. In other examples there may be different numbers of winding connectors 34.

[0056] Each stator leadframe 32 includes a stator leadframe connector 36 arranged in the terminal region 14 of the terminal block portion 4.Figure 3 shows a stator assembly 38 comprising the support 1 of Figure 1, a stator body 40 and three stator leadframes 32 arranged in the grooves 12 of the circumferential frame 6. The winding connectors 34 of the stator leadframes 32 are connected to windings of the stator body 40 to provide power thereto.

[0057] Bolts 42 pass though the three axial fixing holes 20 and into the stator body 40 to secure the support 1 to the stator body 40.

[0058] Figure 4 shows a motor assembly 44 in which the stator assembly 38 of Figure 3 has been arranged inside a motor housing 46 and a rotor 48 has been arranged within the stator assembly 38. The motor housing 46, stator assembly 38 and rotor 48 are all substantially coaxial with the frame axis 8.

[0059] In each terminal region 14, a bolt 50 passes through an aperture in an external connector 52 of a motor controller 54, inverter or other connector, and a stator leadframe connector 36 and is engaged with the securing element 18 in the terminal region 14 to secure the external connector 52 and stator leadframe connector 36 together and retain them in the terminal region 14.

[0060] The terminal block portion 4 of the support 1 is arranged in a recess 56 of the motor housing 46.

[0061] Figure 5 shows a flowchart of a method 58 of assembling a motor assembly 44 as shown in Figure 4. The method 58 comprises fixing 60 a support 1 to the stator body 40 to form a stator assembly 38.

[0062] Stator leadframes 32 are installed 62 into the leadframe guides 10 of the support 1 so that the at least one leadframe 32 extends from a terminal region 14 of the terminal block portion 4 to a winding connector 34. As noted elsewhere, the stator leadframes 32 may be installed before, or after, the support 1 is fixed to the stator body 40.

[0063] The stator assembly 38 is arranged 64 within the motor housing 46 and secured thereto. The terminal block portion 4 and recess 56 in the motor housing 56 are used to rotationally align the support 1 and the motor housing 46. External connectors 52 are arranged and secured 66 in the terminal regions 14 using a fastener 50 to engage a securing element 18in the securing element holder 16. This secures the stator leadframe 32 and external connector 52 together in the terminal region 14.

Claims

Claims1. A support for carrying an element in a motor, the support comprising a leadframe holder portion and a terminal block portion;the leadframe holder portion comprising a circumferential frame extending around a frame axis and comprising at least one leadframe guide to carry a stator leadframe;the terminal block portion extending from the leadframe holder radially away from the frame axis and comprising at least one terminal region, the, or each, terminal region including a securing element carrier arranged such that a stator leadframe connector and an external connector can be arranged in a terminal region and be secured to one another using a securing element arranged in the securing element carrier; andwherein the leadframe holder portion and terminal block portion are formed as a single component.

2. A support as claimed in claim 1, in which the circumferential frame extends continuously around the frame axis.

3. A support as claimed in claim 1 or claim 2, in which the circumferential frame is substantially annular.

4. A support as claimed in any preceding claim, in which the at least one leadframe guide comprises a groove in the circumferential frame.

5. A support as claimed in any preceding claim, in which the circumferential frame includes at least three leadframe guides, each leadframe guide to carry a stator leadframe.

6. A support as claimed in any preceding claim, in which the circumferential frame includes at least one axial fixing hole through which a fixing element can be inserted to secure the support to a motor housing or stator body.

7. A support as claimed in any preceding claim, in which the, or each, securing element carrier of the terminal region comprises a threaded insert to accept a securing bolt.

8. A support as claimed in claim 7, in which the threaded insert is moulded into the securing element carrier.

9. A support as claimed in any preceding claim, in which the terminal block portion comprises a plurality of terminal regions.

10. A support as claimed in claim 9, in which the terminal block portion comprises three terminal regions.

11. A support as claimed in claim 10, in which the three terminal regions are arranged in a line and are substantially evenly spaced in the terminal block portion.

12. A support as claimed in any of claims 9 to 11, in which there are void regions between the terminal regions.

13. A support as claimed in any of claims 9 to 12, in which the terminal regions are connected to the circumferential frame by one or more radial beams.

14. A support as claimed in any of claims 9 to 13, in which the terminal regions are connected to one another by one or more terminal beams.

14. A support as claimed in any preceding claim, in which the terminal block portion comprises side guards which extend axially from circumferential ends of the terminal block portion.

15. A support as claimed in any preceding claim, in which the support is moulded from a plastic material.

16. A motor assembly, the motor assembly comprising a stator body, motor housing, support, at least one leadframe, a securing element, a fastener, and an external connector, the support being as claimed in any preceding claim, in which:the stator body is arranged within the motor housing and the support is arranged at an end thereof;the support carries the at least one leadframe so that the at least one leadframe extends from a terminal region of the terminal block portion to a connector of the stator; the securing element is arranged in the securing element holder of the terminal region; andthe fastener engages with the securing element to secure the leadframe and external connector together in the terminal region.

17. A motor assembly as claimed in claim 16, in which the motor housing includes a recessed region to receive the terminal block portion of the support.

18. A method of assembling a motor assembly, the motor assembly as claimed in claim 16 or claim 17, the method comprising:fixing the support to the stator body to form a stator assembly;installing at least one stator leadframe into the leadframe guide of the support so that the at least one leadframe extends from a terminal region of the terminal block portion to a connector of the stator;arranging the stator assembly within the motor housing; andarranging an external connector in the terminal region and using a fastener to engage a securing element arranged in the securing element holder to secure the leadframe and external connector together in the terminal region.

19. A method as claimed in claim 18, in which arranging the stator assembly within the motor housing comprises aligning the terminal block portion with a recess of the motor housing.

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