Patent Application
20100059352
The present disclosure relates to an electrical contactor and more particularly to a weld-breaking electrical contactor.
This section provides background information related to the present disclosure which is not necessarily prior art.
A winch may be used to move a first object relative to a stationary second object by fixing the winch to one of the objects and engaging the winch's cable to the other object and subsequently winding the cable around a drum mechanism to pull the objects towards each other. Winches are commonly mounted to a vehicle and powered by the vehicle's battery or other power source. Winding and unwinding of a winch cable can be accomplished by switching the polarity of the DC current as applied to the winch motor. Vehicle-mounted winches often include remote control units enabling an operator to selectively wind, unwind and stop the rotation of the winch.
Such remote control units may include a contactor operable to selectively switch the polarity of the DC current and/or discontinue current flow to the motor by selectively engaging and/or disengaging one or more electrical contact members and one or more electrical terminals. High amperage current drawn through engaged contact members and terminals may generate sufficiently high heat to weld the contact member to the terminal, hindering disconnection of the contact member from the terminal.
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
An electric contactor may include a first plunger member supporting a first contact member thereon, the first plunger member being movable between a disengaged position and an engaged position with respect to a first electrical terminal; a second plunger member supporting a second contact member thereon, the second plunger member being movable between a disengaged position and an engaged position with respect to a second electrical terminal; a first linear actuator selectively causing movement of the first plunger from the disengaged position to the engaged position; and a second linear actuator selectively causing movement of the second plunger from the disengaged position to the engaged position. Actuation of one of the first and second linear actuators will apply a weld breaking force against the plunger associated with the other of the first and second linear actuators.
In another form, a contactor may include a first plunger member supporting a first contact member; a second plunger member supporting a second contact member; a first linear actuator adapted to selectively cause movement of the first contact member from a disengaged position to an engaged position relative to a first electrical terminal; a second linear actuator adapted to selectively cause movement of the second contact member from a disengaged position to an engaged position relative to a second electrical terminal; and a rocker selectively engaging the first and second plungers in response to actuation of either of the first and second linear actuators. If a weld develops between the first contact member and the first electrical terminal while the first contact member is in the engaged position, then actuation of the second linear actuator causing the second contact member to move towards the engaged position is operable to break the weld and force the first contact member toward the disengaged position.
In yet another form, a contactor may include a first plunger member supporting a first contact member thereon, the first plunger member being movable between a disengaged position and an engaged position with respect to a first electrical terminal; a second plunger member supporting a second contact member thereon, the second plunger member being movable between a disengaged position and an engaged position with respect to a second electrical terminal; a common armature engaging the first and second plungers, the first and second plungers extending axially therefrom; a first coil disposed around a first portion of the armature, and energizing the first coil causes the first contact member to move into the engaged position; and a second coil disposed around a second portion of the armature, and energizing the second coil causes the second contact member to move into the engaged position. If a weld develops between the first contact member and the first electrical terminal while the first contact member is in the engaged position, then actuation of the second linear actuator causing the second contact member to move towards the engaged position is operable to break the weld and force the first contact member toward the disengaged position.
In still another form, a contactor may include a first plunger member supporting a first contact member; a second plunger member supporting a second contact member, the second plunger being axially aligned with the first plunger member; a first linear actuator adapted to selectively cause movement of the first contact member from a disengaged position to an engaged position relative to a first electrical terminal; a second linear actuator adapted to selectively cause movement of the second contact member from a disengaged position to an engaged position relative to a second electrical terminal; and a spring disposed between the first and second contact members and biasing the first and second contact members away from each other. If a weld develops between the first contact member and the first electrical terminal while the first contact member is in the engaged position, then actuation of the second linear actuator causing the second contact member to move towards the engaged position is operable to break the weld and force the first contact member toward the disengaged position.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
Example embodiments will now be described more fully with reference to the accompanying drawings.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on”, “engaged to”, “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to”, “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
With reference to
The remote control 22 may include a wind button 26, an unwind button 28 and a cord 30 interconnecting the remote control 22 and the electric motor 14 facilitating electrical communication therebetween. An operator may selectively actuate one of the wind button 26 and the unwind button 28 to control the rotational direction of the electric motor 14. The wind and unwind buttons 26, 28 can be of the type disclosed in Assignee's commonly owned U.S. Pat. No. 5,522,582, the disclosure of which is incorporated by reference herein in its entirety. It will be appreciated that a toggle switch (or the like) having wind, unwind and static state positions could be substituted for the wind and unwind buttons 26, 28. The buttons 26, 28 (or the toggle switch) are in electrical communication with a weld-breaking electric contactor 29 (
Referring now to
The solenoids 40, 42 may include first and second coils 56, 58, respectively, and first and second armatures 60, 62, respectively. The coils 56, 58 may each include metallic wiring wound around a generally tubular core. The armatures 60, 62 may be generally cylindrical, magnetic members. Electrical current from the battery 20 (or any other source of electric power) may flow to one of the coils 56, 58 in response to the operator actuating the wind button 26 or unwind button 28, respectively. Current flowing through the first coil 56 or second coil 58 produces a magnetic field which forces the associated armature 60, 62, respectively, upward (relative to the view shown in
The plungers 44, 46 may be elongated, generally cylindrical members and may protrude from the armatures 60, 62, respectively, generally parallel to each other. The plungers 44, 46 may be engaged with the armatures 60, 62, respectively, or integrally formed therewith.
Contact members 48, 50 may be disposed on the plungers 44, 46, respectively, and may include bridge portions 66, 68 and a plurality of metallic protuberances 70. The bridge portions 66, 68 may extend from the plungers 44, 46, respectively, generally perpendicularly from the longitudinal axes thereof, forming generally cross-shaped cross sections. The protuberances 70 may be disposed on distal ends of the bridge portions 66, 68.
Spring members 72, 74 may be disposed around the plungers 46, 48, respectively. At a first end, the spring members 72, 74 may abut the contact members 48, 50, respectively, and at a second end, the spring members 72, 74 may abut a structural member 76. The structural member 76 may be fixed relative to a housing of the contactor 29 and could form a part of the housing. The plungers 44, 46 may be axially movable through apertures in the structural member 76. In this configuration, the spring members 72, 74 compress between the structural member 76 and the contact members 48, 50, respectively, as the associated plunger 44, 46 moves axially from the disengaged position to the engaged position. In this manner, the spring members 72, 74 bias the associated plungers 44, 46 and contact members 48, 50, respectively, toward the disengaged position.
The power circuit 52 may include a power member 80, an armature 82 of the motor 14, and first and second field coil leads 84, 86, respectively, of the motor 14. The power member 80 is in electrical communication with the battery 20. The first and second field coil leads 84, 86 may be in electrical communication with first and second poles of the motor 14. The first field coil lead 84 may have a generally U-shaped cross section including an upper portion 88 and a lower portion 90. The second field coil lead 86 may also have a generally U-shaped cross section including an upper portion 92 and a lower portion 94. Metallic protuberances 96 may be disposed on the power member 80, the armature 82 and the first and second field coil leads 84, 86.
The upper portion 88 of the first field coil lead 84 and a first portion 98 of the power member 80 form a wind terminal 100. The upper portion 92 of the second field coil lead 86 and a second portion 102 of the power member 80 form an unwind terminal 104. Engagement between the wind contact member 48 and the wind terminal 100 via protuberances 70, 96 (
The rocker 54 may include a first arm 106 and a second arm 108 disposed generally above distal ends of the plungers 44, 46 (relative to the views shown in
When both plungers 44, 46 are in the disengaged position (
With continued reference to
For example, actuating the wind button 26 allows electrical current to energize the wind solenoid 40, causing the wind plunger 44 to move upward into the engaged position (
The heat generated by the high amperage current flowing through the first terminal 100 and the wind contact member 48 can cause the protuberances 70, 96 of the contact member 48 and the terminal 100, respectively, to begin to melt and become welded together. The weld bonding the protuberances 70, 96 together may be sufficiently strong to retain the wind contact member 48 in the engaged position against the biasing force of the spring 72, even after the operator has released the wind button 26. In this manner, current may continue to flow through the first terminal 100 and the contact member 48 to the motor 14 even though the operator has released the wind button 26.
If such a welding event occurs, the operator may actuate the unwind button 28, energizing the unwind solenoid 42, thereby forcing the unwind plunger 46 upward toward the engaged position. The upward travel of the unwind plunger 46 forces the second arm 108 of the rocker 54 to rotate upward (relative to the view shown in
It should be appreciated that if the operator holds down unwind button 28 to allow the unwind contact member 50 to reach the engaged position (
With reference to
Wind and unwind coils 56′, 58′ may be disposed around first and second portions 57′, 59′ of the common armature 60′, respectively. Energizing the wind coil 56′ imparts a magnetic force on the first portion 57′ and the wind plunger 44′ causing axial movement of the armature 60′ and both plungers 44′ 46′ to the left (relative to the view shown in
In a similar manner, energizing the unwind coil 56′ imparts a magnetic force on the second portion 59′ of the common armature 60′ and the unwind plunger 46′, causing axial movement of the common armature 60′ and both plungers 44′, 46′ to the right (relative to the view shown in
A first spring member 72′ may be disposed around at least a portion of the wind plunger 44′, between a first fixed structural member 76′ and the wind contact member 48′, thereby biasing the wind contact member 48′ toward a disengaged position (
With continued reference to
In a similar manner, actuation of the unwind button 28 energizes the unwind coil 58′, electromagnetically forcing the common armature 60′ and the unwind plunger 46′ (and hence the wind plunger 44′) to move to the right (relative to the view shown in
As described above, when one of the contact members 48′, 50′ are in the engaged position, heat generated by the high amperage current can weld the contact members 48′ or 50′ to its associated electrical terminal 100′, 104′, respectively, which may retain the contact member 48′ or 50′ in the engaged position despite the biasing force of the corresponding spring member 72′, 74′. If such a weld event occurs between the wind contact member 48′ and the first terminal 100′, for example, the operator may actuate the unwind button 28, thereby energizing the unwind coil 58′. The resultant electromagnetic force moves the plungers 44′, 46′ and common armature 60′ to the right (relative to the view shown in
If a weld event occurs between the unwind contact member 50′ and the second terminal 104′, the weld may be broken in a similar manner as described above. The operator may actuate the wind button 26, energizing the wind coil 58′, thereby electromagnetically forcing the plungers 44′, 46′ and the common armature 60′ to the left (relative to the view shown in
Referring now to
The plungers 44″, 46″ may extend inwardly from wind and unwind armatures 60″, 62″, respectively, and may be generally coaxially aligned and axially movable relative to each other. The contact members 48″, 50″ may be fixedly engaged with the plungers 44″, 46″, respectively. A spring member 72″ may be disposed around one or both of the plungers 44″, 46″, abutting the contact members 48″, 50″. Movement of one of the plungers 44″, 46″ toward the other of the plungers 44″, 46″ compresses the spring member 72″ between the contact members 48″, 50″, which biases the plungers 44″, 46″ away from each other toward disengaged positions (
When both contact members 48″, 50″ are in a disengaged position (
Engagement between the wind contact member 48″ and the first terminal 100″ via protuberances 70, 96, completes an electrical circuit allowing high amperage current to flow from the battery 20, through the power member 80″, through the wind contact member 48″ and into the first field coil lead 84″, thereby causing the motor 14 to rotate in a first direction. Similarly, engagement between the unwind contact member 50″ and the second terminal 104″, via protuberances 70, 96, completes an electrical circuit allowing high amperage current to flow from the battery 20, through the power member 80″, through the unwind contact member 50″ and into the second field coil lead 86″, thereby causing the motor 14 to rotate in a second direction.
With continued reference to
If the wind contact member 48″ and the first terminal 100″ become welded together in the manner described above, the operator may actuate the unwind button 28 to break the weld. Actuating the unwind button 28 energizes the unwind coil 58″, which forces the unwind plunger 46″ to the left (relative to the view shown in
If the unwind contact member 50″ and the second terminal 104″ become welded together in the manner described above, the operator may actuate the wind button 26 to break the weld. Actuating the wind button 26 energizes the wind coil 56″, which forces the wind plunger 44″ to the right (relative to the view shown in
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.
