Patent Application
20130244450
The disclosure is directed to a guide configured for maintaining the leads extending from a brush of a brush holder assembly in a desired position/orientation. More particularly, the disclosure is directed to a brush lead guide for a brush holder assembly configured to retain the leads extending from a brush in a desired position/orientation to ensure the leads do not interfere with movement of the brush within the brush holder.
A purpose of a brush in an electrical device is to pass electrical current from a stationary contact to a moving contact surface, or vice versa. Brushes and brush holders may be used in electrical devices such as electrical generators, electrical motors, and/or slip ring assemblies, or sliding connection applications, for example, slip ring assemblies on a rotating machine such as a rotating crane or a linear sliding connection on a monorail. Brushes in many electrical devices are blocks or other structures made of conductive material, such as graphite, carbon graphite, electrographite, metal graphite, or the like, that are adapted for contact with a conductive surface or surfaces to pass electrical current. Electrically conductive leads or shunts extend from the brush to provide an electrical pathway to and/or from the brush from another conductive member.
In some designs, a brush box type brush holder, or other type of brush holder, may be used to support the brush during operation. The brush and brush box may be designed such that the brush can slide within the brush box to provide for continuing contact between the brush and the conductive surface contacted by the brush. Over time, the brush will be reduced in size, or get shorter (i.e., diminish in longitudinal length), for example, as the wear surface of the brush in frictional contact with the conductive surface wears down. Accordingly, the brush is intended to move within the brush holder. If left unconstrained, the leads extending from the brush may interfere with free movement in the brush holder, as the brush wears down. Accordingly, it is desirable to provide a structure to retain the leads extending from the brush in a desired position/orientation to ensure the leads do not interfere with movement of the brush within the brush holder.
The disclosure is directed to alternative designs, materials and methods of manufacturing electrical brush lead guide structures and assemblies, and uses thereof.
Accordingly, one illustrative embodiment is a lead guide for maintaining the leads extending from a brush of a brush holder assembly in a desired position. The lead guide includes a bracket comprising a first guide rail, a second guide rail, and a cross member extending between the first guide rail and the second guide rail. The first guide rail includes a channel for receiving a first lead of the brush and the second guide rail includes a channel for receiving a second lead from the brush. The bracket is configured to space the first lead away from the second lead to permit a spring of the brush holder assembly to be positioned therebetween.
Another illustrative embodiment is a brush holder assembly for an electrical device. The brush holder assembly includes a brush holder, a brush, and a lead guide. The brush is positionable in the brush holder. The brush includes at least one lead extending from the brush. The lead guide is coupled to the at least one lead and configured to travel with the brush relative to the brush holder as the brush diminishes in length during use. The lead guide is configured to prevent the at least one lead from contacting the brush holder and restricting free movement of the brush in the brush holder. In some instances, the lead guide includes a first guide rail extending along a base portion of a first lead and a second guide rail extending along a base portion of a second lead, with the lead guide positioned between the leads. In some instances, the brush holder assembly includes a spring configured to exert a force against the brush in the brush holder. The spring is positionable between the first guide rail of the lead guide and the second guide rail of the lead guide.
The above summary of some example embodiments is not intended to describe each disclosed embodiment or every implementation of the aspects of the disclosure.
The aspects of the disclosure may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings, in which:
While the aspects of the disclosure are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the disclosure to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.
For the following defined terms, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification.
All numeric values are herein assumed to be modified by the term “about”, whether or not explicitly indicated. The term “about” generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (i.e., having the same function or result). In many instances, the term “about” may be indicative as including numbers that are rounded to the nearest significant figure.
The recitation of numerical ranges by endpoints includes all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).
Although some suitable dimensions, ranges and/or values pertaining to various components, features and/or specifications are disclosed, one of skill in the art, incited by the present disclosure, would understand desired dimensions, ranges and/or values may deviate from those expressly disclosed.
As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.
The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The detailed description and the drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the disclosure. The illustrative embodiments depicted are intended only as exemplary. Selected features of any illustrative embodiment may be incorporated into an additional embodiment unless clearly stated to the contrary.
A brush holder assembly 10, for example as shown in
The brush holder 12 may be secured to a mounting beam 14 configured and adapted to be mounted to another structure, such as a mounting block 30. The brush holder assembly 10 is configured to place the brush 20 in contact with a conductive surface 32, such as a rotating surface of a collector ring, a slip ring, or a commutator, and conduct current therefrom. The brush 20 may extend from the lower edge of the brush holder 12 such that a wear surface 31 of the brush 20 engages the conductive surface 32. The mounting beam 14 may include an over-center engagement mechanism, a slotted or channeled engagement mechanism for sliding engagement, or other mechanism for easily engaging and disengaging the brush 20 from a conductive surface 32.
In some embodiments, the brush holder assembly 10 may substantially resemble a brush holder assembly as described in U.S. Pat. No. 7,034,430, entitled “Brush Holder Apparatus, Brush Assembly, and Method”, which is herein incorporated by reference in its entirety. In other embodiments, the brush holder assembly may include a brush holder rigidly mounted to another structure holding the brush holder stationary, or mounted to another structure in any desired arrangement. For example, in some embodiments the brush holder may be bolted or welded to a stationary structure. Some such brush holders are disclosed in U.S. Pat. Nos. 6,731,042; 5,753,992; 5,621,262; 5,463,264; 5,397,952; and 5,256,925; which are incorporated herein by reference.
As shown in
The mounting beam 14 may be removably coupled to the mounting block 30 during operation. In some embodiments, the mounting beam 14 may slidably engage with, interlock with, or otherwise be removably coupled to the mounting block 30. The mounting block 30 may be coupled to, secured to, or otherwise extend from another structure which maintains the mounting block 30 stationary with respect to the conductive surface 32, for example.
In some embodiments, a handle 22 may be attached to the brush holder 12 to facilitate engagement and disengagement of the brush 20 from the conductive surface 32. For example, the handle 22 may be attached to the upper beam member 16 such that movement of the handle 22 actuates (e.g., pivots, slides, releases) the upper beam member 16 relative to the lower beam member 18 between the disengaged position (
Also illustrated in
The brush 20 may include one or more electrical leads (e.g., shunts), such as braided copper cables, for conducting electricity to and/or from the electrically conductive surface 32 through the brush 20. For example, a first electrical lead 26a and a second electrical lead 26b may extend from the brush 20 to an electrically conductive terminal 28 coupled to a component of the brush holder assembly 10, such as the mounting beam 14. The ends of the leads 26a, 26b may be soldered, brazed, crimped, clamped or otherwise removably or permanently secured to the terminal 28.
The brush holder assembly 10 may also include a brush lead guide 40 configured to retain the leads 26a, 26b extending from the brush 20 in a desired position/orientation to ensure the leads 26a, 26b do not interfere with movement of the brush 20 within the brush holder 12. For example, the guide 40 may maintain the first lead 26a and the second lead 26b in a spaced apart arrangement such that the spring 24 may be positioned between the first lead 26a and the second lead 26b. Furthermore, as shown in
The lead guide 40 may be positioned between the leads 26a, 26b to maintain a proper distance between a base portion of the leads 26a, 26b to accommodate the spring 24 therebetween. The lead guide 40 may be positioned between the leads 26a, 26b and the spring 24 to prevent direct contact between the leads 26a, 26b and the spring 24, and thus prevent the leads 26a, 26b from being cut, worn, scraped, abraded or otherwise damaged by the spring 24.
The portion of the leads 26a, 26b extending from the guide 40 to or toward the terminal 28 may converge and be secured together with a fastener 36, such as a clip, tape, ring, or other mechanism to hold the leads 26a, 26b together. Additional fasteners 36 may be used if desired along portions of the length of the leads 26a, 26b to secure the leads 26a, 26b in a desired arrangement. Accordingly, the fastener 36 may prevent the leads 26a, 26b from spreading apart, while the guide 40 may prevent the leads 26a, 26b from converging together, thus holding the leads 26a, 26b in a desired position. The guide 40 may include first and second channels 46 for receiving the leads 26a, 26b therein to maintain the leads 26a, 26b generally parallel and spaced apart as the leads 26a, 26b extend from the upper surface 21 of the brush 20. In the illustrated embodiment, the lead guide 40 may permit the leads 26a, 26b to flex at the upper surface 21 of the brush 20 toward and/or away from the front and rear surfaces 23, 25 during the life of the brush 20, while preventing the leads 26a, 26b from flexing toward and away from the side surfaces 27, 29 of the brush 20. Thus, the lead guide 40 may be configured to permit a degree of movement of the leads 26a, 26b at the interface with the upper surface 21 of the brush 20 as the brush 20 is moved through the brush holder 12 as the brush 20 is worn.
Turning to
The bracket 60 may include a first guide rail 42a, a second guide rail 42b and a cross member 44 extending between the first guide rail 42a and the second guide rail 42b, such as from an end of the first guide rail 42a to an end of the second guide rail 42b. In some embodiments, the cross member 44 may extend between the first end 48a of the first guide rail 42a and the first end 48b of the second guide rail 42b. In some instances, the bracket 60 may be formed as a unitary member including the first guide rail 42a, the second guide rail 42b and the cross member 44, while in other embodiments the bracket 60 may be formed of multiple members secured together. The first guide rail 42a, which in some instances may be considered a first leg of the bracket 60, may be arranged generally parallel to the second guide rail 42b, which in some instances may be considered a second leg of the bracket 60, or at any desired angle relative to the second guide rail 42b.
The first guide rail 42a may define a channel 46 for receiving a portion of the first lead 26a therein and the second guide rail 42b may define a channel 46 for receiving a portion of the second lead 26b therein. In some instances, the channels 46 of the first and second guide rails 26a, 26b may open out in opposite directions. The channel 46 of the first guide rail 42a may extend from the first end 48a to the second end 49a of the first guide rail 42a, and the channel 46 of the second guide rail 42b may extend from the first end 48b to the second end 49b of the second guide rail 42b.
The brace 50 may be configured to be removably attached to the bracket 60 to prevent relative movement between the first and second guide rails 42a, 42b. For example, the brace 50 may be configured to stabilize the first guide rail 42a relative to the second guide rail 42b, such as to prevent movement of the first and second guide rails 42a, 42b toward and/or away from one another.
The brace 50 may include a cross member 62 extending between the first guide rail 42a and the second guide rail 42b, such as from an end of the first guide rail 42a to an end of the second guide rail 42b. In some embodiments, the cross member 62 may extend between the second end 49a of the first guide rail 42a and the second end 49b of the second guide rail 42b.
The brace 50 may include an engagement interface configured to mate with and engage an engagement interface of the bracket 60 to removably couple the brace 50 to the bracket 60. For example, the brace 50 may include a first end 64a having one or more posts 54, 55 configured to interlock with one or more openings 58, 59 in the first guide rail 42a, and the brace 50 may include a second end 64b having one or more posts 54, 55 configured to interlock with one or more openings 58, 59 in the second guide rail 42b. In some instances, the openings 58 may be through holes extending through the base portion of the guide rails 42a, 42b, and/or the openings 59 may be notches formed on an edge of the side portions of the guide rails 42a, 42b. It is noted that in other embodiments, the bracket 60 may include posts 54, 55 and the brace 50 may including openings 58, 59 for receiving the posts 54, 55, if desired. Other interconnecting structures are also contemplated for removably coupling the brace 50 to the bracket 60 of the lead guide 40.
The first end 64a of the brace 50 may include a first post 54 and a second post 55. As shown in
Similarly, the second end 64b of the brace 50 may include a first post 54 and a second post 55. As shown in
In some embodiments, the first post 54 at the first end 64a of the brace 50 may be co-axial with the first post 54 at the second end 64b of the brace 50, and/or the second post 55 at the first end 64a of the brace 50 may extend parallel to the second post 55 at the second end 64b of the brace 50.
The brace 50 may further include a first stop 56 positionable against the first guide rail 42a when the one or more posts 54, 55 at the first end 64a of the brace 50 are positioned in the one or more openings 58, 59 of the first guide rail 42a, and/or a second stop 56 positionable against the second guide rail 42b when the one or more posts 54, 55 at the second end 64b of the brace 50 are positioned in the one or more openings 58, 59 of the second guide rail 42b.
The stops 56 may be positioned between the first and second guide rails 42a, 42b to prevent movement of the guide rails 42a, 42b toward one another, while the engagement of the posts 55 in the openings 59 may prevent movement of the guide rails 42a, 42b away from one another. Thus, coupling the brace 50 to the bracket 60 may substantially stabilize the first and second guide rails 42a, 42b from movement relative to one another.
The lead guide 40 may also include a wear marker 52 configured to track or follow the movement of the brush 20. For example, the lead guide 40 may be arranged with the brush 20 such that the lead guide 40 moves with the brush 20 as the brush 20 travels in the brush holder 12 during the life of the brush 20. In other words, the lead guide 40 and the brush 20 are configured to move together as the brush 20 is worn during use. Accordingly, movement of the marker 52 may directly correspond to movement of the brush 20. For example, linear or longitudinal displacement of the marker 52 may be equivalent, or otherwise proportional, to the linear or longitudinal movement and/or diminution of the brush 20 as the brush 20 is worn. The marker 52 may include one or more, or a plurality of, indicia or markings, or the like, that may aid in determining the position of the marker 52, and thus the position of the brush 20, as described in U.S. Pat. App. Pub. No. 2008/0291273, herein incorporated by reference in its entirety. As shown in the illustrative embodiment, the marker 52 may be formed integrally with the brace 50 and extend from the cross member 62 of the brace 50. However, in other embodiments, the marker 52 may be a portion of the bracket 60, or the marker 52 may be formed separately and attached to the brace 50, the bracket 60, or another component of the lead guide 40, if desired.
Referring again to the assembled configuration of
In assembling the guide with the leads 26a, 26b of the brush 20, one of the guide rails 42 (either the first guide rail 42a or the second guide rail 42b) of the bracket 60 may be passed through the opening of the coil of the spring 24 such that the first guide rail 42a is positioned on a first side of the coil of the spring 24 and the second guide rail 42b is positioned on a second side of the coil of the spring 24. The first lead 26a may be positioned in the channel 46 of the first guide rail 42a and the second lead 26b may be positioned in the channel 46 of the second guide rail 42b. As shown in
The cross member 62 of the brace 50 may be passed through the opening of the coil of the spring 24, and the ends 64a, 64b of the brace 50 may be coupled to the respective guide rails 42a, 42b, as described above. For example, the posts 54 may be inserted into the openings 58 on opposite sides of the spring 24 with the stops 56 pressed against the first and second guide rails 42a, 42b, and the posts 55 may be inserted into the openings 59 on opposite sides of the spring 24. Engagement of the brace 50 between the guide rails 42a, 42b of the bracket 60 may stabilize the guide rails 42a, 42b from movement toward and/or away from one another.
The portions of the leads 26a, 26b extending from the guide 40 to or toward the terminal 28 may be brought toward one another such that the leads 26a, 26b converge above the lead guide 40. The portions of the leads 26a, 26b extending from the guide 40 may be secured together with a fastener 36, such as a clip, tape, ring, or other mechanism to hold the leads 26a, 26b together. Additional fasteners 36 may be used if desired along portions of the length of the leads 26a, 26b to secure the leads 26a, 26b in a desired arrangement. Accordingly, the fastener 36 may prevent the leads 26a, 26b from spreading apart, while the guide 40 may prevent the leads 26a, 26b from converging together, thus holding the leads 26a, 26b in a desired position.
The terminal 28 may be coupled to an electrically conductive member to complete an electrical connection from the brush 20.
Those skilled in the art will recognize that aspects of the present disclosure may be manifested in a variety of forms other than the specific embodiments described and contemplated herein. Accordingly, departure in form and detail may be made without departing from the scope and spirit of the present disclosure as described in the appended claims.
