AU2014202640B2 - Starter motor - Google Patents

Abstract

A vehicle starter motor including: a housing 11; an armature and a commutator each rotatably located within the housing 11, the commutator being for providing electric current to the armature; a brush plate 40 located within the housing 11 and including electrically conductive brushes through which an electric current can be delivered to the commutator; a first earth terminal 14 in electrical communication with the brush plate 40 and electrically insulated from the housing 11 and extending through a wall 13 of the housing 11 to outside of the housing 11; a second earth terminal formed from a first conductive member 24 in electrical communication with the brush plate 40 and a second conductive member 50 attached to the first conductive member 24, the second earth terminal 50 being electrically insulated from the housing 11 and extending through a wall of the housing 11 to outside of the housing 11. (N &"'\ ~N\k ~'N"" C' C" -~ ' NNN~~ ~ '~ 'NN~ C'N ~JN \ ,N'-'~'~~' y"'*'\ ""~' ?'.. ~'NNN' '\ \NNN'. -' ~ N~k~' N~ NN~'.'.. N 'N N \ \ NV'..'. V N'. -N'' CNn 4. 'S N '\ Li "N K'. 7'> 'tti UN NNNN K> ~ K; ~ "NNNNN

Description

Technical Field [0002] The present invention relates to a vehicle starter motor and in particular to improvements in the earthing capacity of starter motors.

Background of Invention [0003] The following discussion of the background to the invention is intended to facilitate an understanding of the invention. However, it should be appreciated that the discussion is not an acknowledgement or admission that any aspect of the discussion was part of the common general knowledge as at the priority date of the application.

[0004] Vehicle electrical systems include a number of electrical components located throughout the vehicle engine and chassis. These components typically include an alternator, an engine control unit (ECU), a transmission control unit (TCU) and a starter motor. Each of these components requires an electrical connection with a current supply from the positive terminal of a vehicle battery in addition to an earth connection thereby forming the requisite voltage drop across the component. The earth connection is often made by connecting the components directly to the vehicle chassis or engine block as these are in electrical contact with the negative terminal of the vehicle battery and thus the electrical circuit is completed.

[0005] The vehicle starter motor has been a convenient point for earthing various electric components of a vehicle and so some starter motors, particularly for trucks, include an earth terminal that is connected to the brush plate of the starter motor and which extends through the starter motor housing, usually through the commutator cover of the housing, so that various electric components can be connected to that terminal as an earth. While this has been an effective point to provide an earth, there are limitations as to the size of the terminal and the amount of connections that can be made to it. Moreover, simply extending the terminal for a greater length is

2014202640 15 May 2014 impractical due to the large mechanical forces which are applied to it by the weight of the earth connections that it supports.

[0006] The practice of earthing the various electric components which are not immediately adjacent each other to neighbouring metallic components of the vehicle, such as the engine block or chassis, can result in electrical current travelling through these components toward the region of lowest electrical potential. These represent stray currents that form undesirable ‘ground loops’ which can contribute to electrolysis within the chassis, engine block, cabin, radiator or other metallic framework in the vehicle.

[0007] A solution to this problem has been proposed in Australian Application No. 2012216470 which discloses a vehicle starter motor that has been retrofitted to include a second earth terminal. This second terminal can therefore be used as an alternative earthing location for various electric components discussed above thereby reducing the occurrence of stray current.

[0008] The various advantages of including a second earth terminal on a vehicle starter motor are discussed in the above document. Consistent with the discussion above, the existing earth terminal is inadequately sized to receive more than a small number of connections and extension of this first terminal is not a practical solution due to the large load of additional connections. The second terminal of the disclosure is installed into a hole which is drilled in the brush plate of an existing starter motor before the second terminal is pressed into the brush plate such that it is fixed onto the brush plate via an interference fit.

[0009] Applicant believes a problem with this existing dual earth starter motor is the amount of labour involved in attaching the second earth terminal. Following the removal of the brush plate from the starter motor, a hole of specific size must be drilled through the brush plate involving risk of heat or mechanical damage occurring to the electronic components attached nearby. A press and accompanying skilled operator is then required to fix the second terminal to the brush plate by an interference fit. Each of these steps involves skilled labour which contributes to the cost of the product.

2014202640 29 Jun2018 [0010] Applicant considers it would therefore be desirable to provide improved and/or alternative dual earth starter motor and an improved and/or alternative method of retrofitting a second earth terminal to a vehicle starter motor.

SUMMARY OF INVENTION [0011] In broad terms, the present invention provides a vehicle starter motor including:

• a housing;

• an armature and a commutator each rotatably located within the housing and the commutator being for providing electric current to the armature;

• a brush plate located within the housing and including electrically conductive brushes through which an electric current can be delivered to the commutator;

• a first earth terminal in electrical communication with the brush plate and electrically insulated from the housing and extending through a wall of the housing to outside of the housing;

• a second earth terminal formed from a first conductive member in electrical communication with the brush plate and a second conductive member attached to the first conductive member, the second earth terminal being electrically insulated from the housing and extending through a wall of the housing to outside of the housing, the second conductive member including an external thread on which a nut is threaded to bear against the housing thereby fixing the second conductive member to the housing.

[0012] A starter motor according to the present invention advantageously can utilise an existing connection between the brush plate and the housing to form the second earth terminal. That is, in some existing starter motors, the brush plate is secured within the housing by a pair of threaded connectors, a first of which is connected to and extends though the housing for use as an earth terminal and the second of which is connected or secured to the housing. The brush plate is thus securely connected to the housing at two positions by the pair of threaded connectors. The present invention advantageously can utilise the second of the connectors in a unique manner to attach a conductive member so that a second earth

3a

2014202640 29 Jun2018 terminal is created that can support further earth connections in addition to those that are attached to the first earth terminal. This is in contrast to the disclosure of

2014202640 15 May 2014 are attached to the first earth terminal. This is in contrast to the disclosure of Australian Application No. 2012216470 in which the second of the connectors is removed and is replaced by a new connector which is fixed onto the brush plate by an interference fit.

[0013] The use of the present invention in relation to existing starter motors advantageously can modify those motors retrospectively, to increase the number of earth connections that can be made to the starter motor. Alternatively, it is within the scope of the present invention that the starter motor be formed in accordance with the invention, so its original construction includes first and second earth terminals. The advantage here is that the construction of a starter motor need not necessarily change from its current construction, other than the addition of second conductive member. That is, no major reconfiguration of an existing style of starter motor is required to adopt the present invention.

[0014] As indicated above, a second earth terminal extends through a wall of the housing of the starter motor so it projects to a position outside of the housing for connection with the earth terminals of electric components of a vehicle. In some forms of the invention, the first conductive member of the second earth terminal can extend from the brush plate to a position outside of the housing. In some forms of this arrangement, the first conductive member can include an external thread and the second conductive member can include a threaded bore which is in threaded engagement with the external thread of the first conductive member. The external thread can extend for any suitable portion of the first conductive member. In some forms, the thread can extend along substantially the full length of the first conductive member, while in other forms, only a portion of the first conductive member includes a thread. For example, the threaded portion can be at the end of the first conductive member adjacent the brush plate and extend for between 50% and 70% of the length of the first conductive member, or it can commence away from the brush plate and extend to or adjacent to the opposite end of the first conductive member. A threaded portion can alternatively be provided that is positioned between the opposite ends of the first conductive member.

[0015] The threaded bore of the second conductive member can be threaded fully from the open end to the opposite end of the bore. Alternatively, a portion of the bore

2014202640 15 May 2014 can be threaded. In some forms of the invention, the inner end of the bore is threaded and extends towards but terminates prior to the open end. The extent of the thread can be between 30% and 70% of the length of the bore.

[0016] Where the first and second conductive members connect by threaded engagement, the second conductive member can thread onto the first conductive member tightly so as bear against the brush plate or against components of the brush plate such as spacers and gaskets. The second conductive member effectively engages the first conductive member like a threaded nut. The second conductive member can include a tightening portion for engagement with a tool for tightening of the threaded engagement between the first and second conductive members, such as a knurled portion, a hexagonal portion or an Allen key recess.

[0017] The second conductive member can bear against the housing when in engagement with the first conductive member to secure the brush plate in position. The second conductive member can include a flange for that purpose. Alternatively, the first conductive member can extend through the housing and connect to the housing by a threaded nut for example, separately to the connection of the second conductive member to the first conductive member.

[0018] Still alternatively, each of the first and second conductive members can extend through the housing, with the portion of first conductive member that is outside the housing being received within a threaded bore of the second conductive member. In this form of the invention, the second conductive member can include an external thread to receive a threaded nut to fix the second conductive member to the housing. By this arrangement, the first and second conductive members are threadably connected, while the second earth terminal is fixed in place relative to the housing by the threaded connection between the nut and the second conductive member.

[0019] Where the invention is applied to an existing starter motor in which the brush plate is secured within the housing by a pair of threaded connectors, in forms of the invention in which the second conductive member is connected to one of the threaded connectors and extends through the housing, such as through the cover of the housing, the opening in the cover through which the threaded connector extends and to which the second conductive member is to be fixed will sometimes be required

2014202640 15 May 2014 to be enlarged. This can be achieved by removing the cover of the starter motor and enlarging the opening by drilling. This is a simple operation and does not require high skill levels.

[0020] The first conductive member can be formed with an elongate spindle or shank that is threaded if required and a head at one end of the shank. The head can be fixed to one side of the brush plate by any suitable manner, such as by adhesive, or by welding, soldering or brazing.

[0021] In some forms of the invention, the shank of the first conductive member is almost fully received by the second conductive member, within a threaded bore of that member. Thus, one end of the second conductive member is positioned close to the head of the first conductive member, with the brush plate and other components of the brush plate such as spacers and gaskets, sandwiched between the head and the facing end of the second conductive member.

[0022] To electrically insulate each of the first and second conductive members from the housing, any suitable arrangements can be adopted. Non-conductive spacers or washers can be employed for this purpose for example.

[0023] Where the invention is applied to an existing starter motor in which the brush plate is secured within the housing by a pair of threaded connectors, for strength purposes, the second conductive member can be of significantly greater diameter than the threaded connector to which the second conductive member connects. Thus the second conductive member can be twice the diameter of the threaded connector or greater. This strengthens the second earth terminal so that it can bear greater load. A greater diameter of the second conductive member also allows for greater contact between the second earth terminal and the terminal connections of the electric components connected to the second earth terminal.

[0024] The length of the second earth terminal that extends from the housing can be the same as the first earth terminal or it can be lesser or greater. In some forms of the invention, the length of the second earth terminal that extends from the housing is about 3 to 4cm.

2014202640 15 May 2014 [0025] The housing will often include the cover referred to above and that cover is usually a removable commutator cover through which each of the first and second earth terminals will extend. In some forms, the first and second conductive members of the second earth terminal will each extend through the commutator cover.

[0026] The invention further provides a method of equipping a vehicle starter motor with a second earth terminal, the vehicle starter motor having:

• a housing including a removable commutator cover;

• an armature rotatably located within the housing and a commutator rotatably located within the commutator cover for providing electric current to the armature;

• a brush plate located within the housing and including electrically conductive brushes through which an electric current can be delivered to the commutator;

• a first earth terminal in electrical communication with the brush plate and electrically insulated from the housing and extending through a wall of the housing to outside of the housing;

• a first conductive member in electrical communication with the brush plate; the method including the steps of:

- removing the commutator cover from the housing;

- attaching a second conductive member in mechanical connection and electric communication with the first conductive member for use as a second earth terminal;

- applying insulation to electrically isolate the second conductive member from the housing;

- refitting the commutator cover to the housing.

[0027] Typically, the second conductive member will have a diameter larger than the diameter of the first conductive member and the method will further include the step of drilling an opening in the commutator cover, the opening being sized to allow the second conductive member to protrude through the opening in the commutator cover.

2014202640 15 May 2014

Brief Description of the Drawings [0028] The present invention will now be described with reference to the figures of the accompanying drawings, which illustrate particular preferred embodiments of the present invention, wherein:

[0029] Figure 1 is a perspective view of a prior art single earth heavy vehicle starter motor;

[0030] Figure 2 is an exploded view of a brush plate of the starter motor of Figure 1 including a second earth terminal in accordance with a preferred embodiment of the present invention;

[0031] Figure 3 is an assembled view of the brush plate of Figure 2;

[0032] Figure 4 is a cross-sectional view of the second earth terminal of Figures 2 and 3.

[0033] Figure 5 is a perspective view of a dual earth vehicle starter motor in accordance with a preferred embodiment of the present invention.

Detailed Description of the Drawings [0034] Figure 1 illustrates one end (the relevant end for the purposes of this discussion) of a prior art vehicle starter motor 10, for example a Delco Remy 39MT, which is compatible for retrofitting a second earth terminal in accordance with the present invention, or for constructing as an original unit with a second earth terminal. For the purposes of this description, the invention depicted in the drawings is a starter motor to which a second earth terminal is to be retrofitted.

[0035] The starter motor 10 includes various components including an armature and a commutator (not visible in Figure 1), a motor body 11 and a commutator cover 12 (hereinafter the “cover 12”). The commutator is within the cover 12. Those components, including the armature and the commutator operate in the normal way of any starter motor as understood by a person skilled in the art and no further discussion in relation to the manner in which they operate needs to be made.

2014202640 15 May 2014 [0036] A critical component of the starter motor 10 in relation to the present invention is the brush plate 40 that is illustrated in Figures 2 and 3. With reference to those figures and to Figure 1, the brush plate 40 is located inside the cover 12 for operational contact with the armature and the commutator during operation of the starter motor 10. A first earth terminal 14 in electrical communication with the brush place 40 is illustrated extending from inside the cover 12 through an opening in the end wall 13 of the cover 12 to outside of the cover 12 for the attachment of earth terminals of electric components of the vehicle to which the starter motor 10 is employed. The first earth terminal 14 is part of the prior art and the advantages of using the first earth terminal and the deficiencies associated therewith have been described above. The first earth terminal 14 is also one of a pair of threaded connectors that connect the brush plate in place within the housing 11.

[0037] A connecting member 24 is also illustrated in Figures 1 and 2 and is also in electrical communication with the brush plate 40. The connecting member 24 is threaded and forms the other of the pair of threaded connectors mentioned above, that connect the brush plate in place within the housing 11.

[0038] The brush plate 40 comprises a conductive metal plate 44 and has two sides, an ‘inside’ which faces the internal components of the motor 10 and an Outside’ which faces the end wall 13 of the cover 12. On the inside, the brush plate 40 supports electrically conductive positively charged brushes (none of which is visible in the figures but would be evident to a person skilled in the art) for delivering electric current to a commutator (not shown) which, in turn, delivers electric current to an armature (not shown) for the conversion of electrical energy to mechanical (rotational) movement. In addition to supporting positive brushes for providing current to the commutator, the brush plate 40 supports earthing brushes 42 for earthing the commutator. The earthing brushes 42 are in electrical communication with the metal plate 44 which is earthed via electrical connection with the first earth terminal 14 which is typically in electrical communication with the negative terminal of the vehicle battery.

[0039] The first earth terminal 14 comprises a threaded bolt having a shaft 15 and a head (not shown). The first earth terminal 14 protrudes through an opening in the wall 13 of the cover 12 (which is obscured by other components to be described

2014202640 15 May 2014 below) and is typically fixed to the brush plate 40 by soldering, in particular silver solder. The head of the first earth terminal 14 abuts the inside of the brush plate 40 (the side on which the earthing brushes 42 are located), and the shaft 15 extends through the brush plate 40 and protrudes from the opposite and outside of the brush plate 40 and through the end wall 13 as shown in Figure 1. The solder connection between head of the first earth terminal 14 and the brush plate allows for electrical communication between the first earth terminal 14 and the brush plate 40.

[0040] Figure 1 illustrates the first earth terminal 14, fitted with a collared spacer 16 (which obscures the opening in the end wall 13 through which the terminal 14 extends) to electrically isolate the first earth terminal 14 from the cover 12. The collared spacer 16 is secured by a first flanged nut 18 which is threadably engaged with the first earth terminal 14. The first earth terminal 14 is sized to receive an earth connector 20 located between a washer 19 and a second flange nut 22. The earth connector 20 is a ring type connector comprising a wire (not shown) in electrical contact with a metallic disc 20 having a central opening for receiving the first earth terminal 14. The first earth terminal 14 has a length sufficient to allow multiple earth connectors to be attached and secured by the second flange nut 22.

[0041] The starter motor 10 includes a second earth terminal which in an assembled condition comprises a first conductive member (in this case the connecting member 24 - hereinafter referred to as the “first conductive member 24”) and a second conductive member 50 described separately hereinafter.

[0042] As discussed above the first conductive member 24 is used in the prior art starter motor arrangement to secure the brush plate 40 within the cover 12 against dislodgement during operation of the starter motor and subsequent operation of the vehicle under drive of the vehicle engine. Figures 1 and 2 illustrate that the first conductive member 24 has an external thread 25 and is sized to protrude through the end wall 13 of the cover 12. In alternative embodiments, the first conductive member 24 could engage with the cover 12, such as threadably engage. The first conductive member 24 could also be sized such that it does not protrude through the cover 12.

[0043] The first conductive member 24 is shown in the figures as a threaded bolt having a shaft and a head (not shown). Similar to the first earth terminal 14, the first

2014202640 15 May 2014 conductive member 24 is fixed to the metal plate 44 of the brush plate 40 by soldering the head to the plate 44, although alternative fixing could be used. The first conductive member 24 is fixed to the cover 12 by a nut 30 in threaded engagement with the first conductive member 24 and is also fixed to the brush plate 40 as described above. The member 24 extends through a collared, insulated, spacer 26 and a washer 28 for electrical isolation from the cover 12. The first earth terminal 14 and the first conductive member 24 are each secured to the brush plate 40 and to the cover 12 and therefore cooperate to secure the brush plate 40 relative to the cover

12.

[0044] Figures 2 and 3 illustrate the second conductive member 50 which attaches to the first conductive member 24 so that the member 50 is indirectly attached to the brush plate 40 to complete the second earth terminal. The second member 50 is elongate and has a base 52 and a shaft 54 which has an external thread. Figure 4 illustrates the second member 50 having a threaded bore 58 which is sized to threadably engage with the external thread of the second member 24. The thread of the bore 58 is formed for only a portion of the bore as it is only required to thread onto the thread 25 at the top of the member 24. The second member 50 includes a tightening portion 56 at its base 52. The tightening portion 56 provides a gripping point for a tightening or rotating tool (not shown) or for finger gripping, to threadably engage first member 24 and the second member 50 together into tight connection. In the illustrated embodiment, the tightening portion 56 is a knurled portion for finger tightening or tightening by a wrench or the like, however various other shapes could be used such as a polygonal portion, in particular a hexagonal section for engagement with a spanner.

[0045] Figure 5 illustrates the member 50 spaced from but ready for threadable engagement with the member 24. Once engaged, the member 50 will extend through the opening 51 of the end wall 13 of the cover 12 and into the cover 12. The member 50 protrudes into the cover 12 to a position close to the brush plate 40, but not into engagement with the brush plate. The member 50 sandwiches components of the starter motor between it and the brush plate. Thus, the member 50 sandwiches between it and the brush plate 40, the gasket 53 (see Figures 2 and 3) and a spacer (not shown) between the gasket 53 and the metal plate 44. The member 50 can be tightened down tightly in that sandwich position to securely engage the member 24.

2014202640 15 May 2014

The member 50 is sized to have a noticeably larger diameter than the member 24 for increased strength and for better fitting with the earthing connections 20. Accordingly, the opening 51 which receives the member 50 is required to be larger than the normal opening in the end wall 13 through which the member 24 protrudes in prior art arrangements. The diameter of the opening 51 has thus been increased to be slightly larger than the outside diameter of the knurled portion 56 by drilling to accommodate the member 50.

[0046] It will be apparent from the figures that the member 24 protrudes out of the cover 12 and that the member 50 threadably engages the member 24 on the threaded portion 25 of that member which is outside the cover 12. It will be further apparent that the member 50 extends into the cover 12 so as to firmly engage the member 24 in the sandwiched arrangement discussed above. That firm engagement could be provided by alternative arrangements and some arrangements advantageously would not require the member 50 to enter the cover 12 and for the opening 51 to have to be enlarged to accommodate the member 50. However, the arrangement that has been illustrated provides firm connection between the members 24 and 50 without significant effort or expense.

[0047] The member 50 is fitted with a collared spacer 126 to electrically isolate the member 50 from the cover 12. A flanged nut 122 is used to secure the collared insulated spacer 126. A spring washer and locking nut 130 are used to secure additional earthing connections onto the member 50 between the nuts 130 and 122.

[0048] Figure 5 thus illustrates the increase in available space for securing additional earthing connections to the starter motor 10 by the use of the second earth terminal of members 24 and 50. The additional space effectively doubles the number of earthing connections that can be made to the starter motor 10.

[0049] The present invention also discloses a method of installing a second earth terminal to a starter motor which can be simply performed without high risk of damage to the electrical components on the brush place 40. The method can be applied to a starter motor 10 having a brush plate 40 with a first earth terminal 14 and a first member 24 being used to fix the brush plate 40 in position. The method includes the steps of removing the various nuts 18, 22, 30 washers 28, connectors, 20, and

2014202640 15 May 2014 spacers 16, 26 attached to the first earth terminal 14 and the first member 24. The cover 12 will typically need to be removed to gain access to the brush plate 40 and once access has been achieved, the second member 50 is attached by threading to the member 24. In some arrangements it will be possible to attach the member 50 without removing the cover 12 from the motor 10, for example where the opening 51 is already sufficiently sized to receive the member 50. In most cases, where the opening 51 is not large enough to receive the member 50, the method will include the step of drilling the larger opening 51 into the end wall 13 of the cover 12.

[0050] The method then includes the step of replacing the cover 12 onto the body 11 of the motor 10 with the member 50 protruding through the opening 51 in the wall 13 of the cover 12 such that it is capable of use as a second earth terminal. Finally, a correspondingly sized collared, insulated spacer 26, washers 28 and a nut 30 are used to secure the second earth terminal to the cover 12 and also to secure the earthing connections which are to be connected to the second earth terminal.

[0051] The present invention therefore provides a vehicle starter motor with a second earth terminal and a method of retrofitting a starter motor with a second earth terminal. The present invention reduces the risk of metal decomposition occurring from electrolysis by providing an additional earthing point for electrical connections which would otherwise have been earthed on the engine block, or vehicle chassis causing stray current to travel through the vehicle.

[0052] It will be appreciated that in some forms of the present invention, the invention utilises an existing connector of an existing starter motor to form part of a second earth terminal and in those forms of the invention, there is no significant modification to the brush plate of the existing starter motor. A starter motor according to the present invention can therefore be manufactured without drilling of the brush plate as required in Australian Application No. 2012216470. Additionally, the method for installing a second earth terminal to an existing starter motor can be performed without the need for a press or a skilled user to operate it.

[0053] Throughout the description and claims of this specification the word “comprise” and variations of that word, such as “comprises” and “comprising”, are not intended to exclude other additives, components, integers or steps.

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Claims (19)

1. THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

   1. A vehicle starter motor including:

   • a housing;

   • an armature and a commutator each rotatably located within the housing the commutator being for providing electric current to the armature;

   • a brush plate located within the housing and including electrically conductive brushes through which an electric current can be delivered to the commutator;

   • a first earth terminal in electrical communication with the brush plate and electrically insulated from the housing and extending through a wall of the housing to outside of the housing;

   • a second earth terminal formed from a first conductive member in electrical communication with the brush plate and a second conductive member attached to the first conductive member, the second earth terminal being electrically insulated from the housing and extending through a wall of the housing to outside of the housing, the second conductive member including an external thread on which a nut is threaded to bear against the housing thereby fixing the second conductive member to the housing.
2. 2. A vehicle starter motor according to claim 1, the first conductive member extending through a wall of the housing to outside of the housing and the second conductive member being connected to the portion of the first conductive member that extends outside of the housing.
3. 3. A vehicle starter motor according to claim 1 or 2, the first conductive member including an external thread and the second conductive member including a threaded bore in threaded engagement with the external thread of the first conductive member.
4. 4. A vehicle starter motor according to claim 3, the external thread of the first conductive member commencing at a position spaced away from the brush plate.
5. 5. A vehicle starter motor according to claim 3, the external thread of the first conductive member being at a position adjacent the brush plate.

   2014202640 29 Jun2018
6. 6. A vehicle starter motor according to any one of claims 3 to 5 wherein the second conductive member includes a tightening portion for engagement by a tool for tightening of the threaded engagement between the first and second members.
7. 7. A vehicle starter motor according to claim 6 wherein the tightening portion is a knurled portion.
8. 8. A vehicle starter motor according to claim 6 wherein the tightening portion is a polygonal portion.
9. 9. A vehicle starter motor according to any one of claims 1 to 8, a locking nut being threaded onto the second conductive member to secure earthing connections onto the second conductive member.
10. 10. A vehicle starter motor according to any one of claims 1 to 9, one end of the second conductive member extending into the housing.
11. 11. A vehicle starter motor according to claim 10, the end of the second conductive member that extends into the housing extending to a position adjacent to the brush plate.
12. 12. A vehicle starter motor according to any one of claims 1 to 11, wherein the first and second earth terminals are electrically isolated from the housing.
13. 13. A vehicle starter motor according to any one of claims 1 to 12 wherein the diameter of the second conductive member about twice the diameter of the first conductive member.
14. 14. A vehicle starter motor according to any one of claims 1 to 13, the housing including a removable commutator cover and each of the first and second earth terminals extending through the commutator cover.
15. 15. A vehicle starter motor according to claim 14, the first and second conductive members each extending through the commutator cover.
16. 16. A method of equipping a vehicle starter motor with a second earth terminal, the vehicle starter motor having:

    2014202640 29 Jun2018 • a housing including a removable commutator cover;

    • an armature rotatably located within the housing and a commutator rotatably located within the commutator cover for providing electric current to the armature;

    • a brush plate located within the housing and including electrically conductive brushes through which an electric current can be delivered to the commutator;

    • a first earth terminal in electrical communication with the brush plate and extending through a wall of the housing to outside of the housing;

    • a first conductive member in electrical communication with the brush plate;

    the method including the steps of:

    removing the commutator cover from the housing;

    attaching a second conductive member in mechanical connection and electric communication with the first conductive member for use as a second earth terminal;

    applying insulation to electrically isolate the second conductive member from the housing;

    refitting the commutator cover to the housing.
17. 17. The method according to claim 16, the second conductive member having a diameter larger than the diameter of the first conductive member and the method further including the step of drilling an opening in a wall of the commutator cover, the opening being sized to allow the second conductive member to protrude through the opening in the commutator cover.
18. 18. A second conductive member for use in the starter motor according to any one of claims 1 to 15.
19. 19. A second conductive member for use in the method according to claim 16 or

    17.

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