The present disclosure relates to handle assemblies for circuit breakers.
Current limiting circuit breakers typically include a manual operating handle configured to switch the circuit breaker between on, off, and trip states. Typically, a portion of the handle extends out of the circuit breaker case or housing for manual operation of the circuit breaker. However, it is common for undesirable products, such as dust, water, and other contaminants, to enter the circuit breaker through gaps formed between the manually operable handle and the opening in the circuit breaker case or housing through which the handle projects. The enclosures of certain circuit breakers, such as UL50E Type 12 enclosures, must be constructed to meet governing body mandated standards. These standards include certain requirements regarding prevention of dust, water spray, and other such contaminants from entering the circuit breaker enclosure via, for example, the handle opening.
According to one aspect of the present disclosure, a handle assembly may comprise a housing defining a first aperture, a seal extending around a perimeter of the first aperture, a handle extending outwardly through the first aperture and pivotable about a pivot axis located within the housing, a shroud coupled to the handle to move therewith and located at least partially within the housing, the shroud including an outer surface that faces the seal, and a biasing member connected to the handle and to the shroud, the biasing member biasing the outer surface into continuous engagement with the seal throughout an entire pivotable range of the handle.
In some embodiments, the handle may comprise a handle arm arranged at least partially within the housing, the handle arm having a first end coupled to the housing at a pivot point located on the pivot axis and a second end located opposite the first end, and a manually operable outer handle portion arranged on the second end of the handle arm.
In some embodiments, the shroud may be arranged on the handle arm and slidable along a longitudinal extent of the handle arm. The biasing member may be arranged within the outer handle portion and coupled to the shroud to bias the shroud toward the outer handle portion.
In some embodiments, the second end of the handle arm may be arranged outside of the housing. The shroud may be arranged on the handle arm such that at least a portion of the shroud protrudes out of the first aperture.
In some embodiments, the outer surface of the shroud may have an arcuate shape. A circumferential extent of the outer surface may be located partially within the housing.
In some embodiments, the arcuate shape of the outer surface may be concentric with the pivot axis. The outer surface may include a first circumferential portion and a second circumferential portion extending in opposite directions away from the handle arm. The first circumferential portion and the second circumferential portion may be symmetrical.
In some embodiments, the outer surface may have a curved cross-sectional shape. The seal may include a first side wall, a second side wall, a first end wall, and a second end wall each projecting inwardly toward the outer surface. The first side wall and the second side wall may each include an inner side wall edge that has the same contour as the arcuate shape of the outer surface. The first end wall and the second end wall may each include an inner end wall edge that has the same contour as the curved cross-sectional shape of the outer surface. The inner side wall edges of the first and second side walls as well as the inner end wall edges of the first and second end walls may define an inner sealing edge that engages the outer surface of the shroud.
In some embodiments, the outer handle portion may be hollow, and the biasing member may be disposed entirely within the outer handle portion. A first end of the biasing member may be coupled to a top portion of the outer handle portion, and a second end of the biasing member may be coupled to a top portion of the seal. The biasing member may be a pressure spring.
In some embodiments, the shroud may include a central hole through which the handle arm extends to allow the shroud to slide along the handle arm.
According to another aspect of the present disclosure, a circuit breaker comprise a circuit breaker case, at least two electrical terminals configured to automatically separate when an overload of current occurs at the at least two electrical terminals, and a handle assembly arranged at least partially within the circuit breaker case and including a handle configured to manually operate the at least two electrical terminals. The handle assembly may comprise a housing defining a first aperture, the housing having seal extending around a perimeter of the first aperture, the handle extending outwardly through the first aperture and pivotable about a pivot axis located within the housing, a pivotable range of the handle being delimited by the first aperture. The handle assembly may further comprise a shroud coupled to the handle to move therewith and located partially within the housing, the shroud including an outer surface that faces the seal. handle assembly may also comprise a biasing member connected to the handle and to the shroud, the biasing member biasing the outer surface into continuous engagement with the seal throughout the entirety of the pivotable range of the handle.
In some embodiments, the handle may comprise a handle arm arranged at least partially within the housing and having a first end coupled to the housing at a pivot point located on the pivot axis and a second end located opposite the first end. The handle may further comprise a manually operable outer handle portion arranged on the second end of the handle arm.
In some embodiments, the shroud may be arranged on the handle arm and slidable along a longitudinal extent of the handle arm. The biasing member may be arranged within the outer handle portion and coupled to the shroud to bias the shroud toward the outer handle portion. The shroud may be arranged on the handle arm such that at least a portion of the shroud protrudes out of the first aperture.
In some embodiments, the outer surface of the shroud may be arcuate. A circumferential extent of the outer surface may be located partially within the housing.
In some embodiments, the arcuate outer surface may be concentric with the pivot axis. The outer surface may include a first circumferential portion and a second circumferential portion extending in opposite directions away from the handle arm.
In some embodiments, the outer handle portion may be hollow, and the biasing member may be disposed entirely within the outer handle portion. A first end of the biasing member may be coupled to a top portion of the outer handle portion, and a second end of the biasing member may be coupled to a top portion of the shroud.
The concepts described in the present disclosure are illustrated by way of example and not by way of limitation in the accompanying figures. For simplicity and clarity of illustration, elements illustrated in the figures are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, the same reference labels or similar reference labels (e.g., reference labels ending in the same two digits) have been repeated among the figures to indicate corresponding or analogous elements. The detailed description particularly refers to the accompanying figures in which:
While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific exemplary embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the concepts of the present disclosure to the particular forms disclosed, but, on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
In the following description, numerous specific details, such as types and interrelationships of circuit components, are set forth in order to provide a more thorough understanding of the present disclosure. It will be appreciated, however, by one skilled in the art that embodiments of the disclosure may be practiced without such specific details. In other instances, various circuit components have not been shown in detail (or not labeled in every instance) in order to not obscure the invention. Those of ordinary skill in the art, with the included descriptions, will be able to implement appropriate functionality without undue experimentation.
References in the specification to “one embodiment,” “an embodiment,” “an illustrative embodiment,” etcetera, indicate that at least one embodiment described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
A handle assembly 10 that may be used in a circuit breaker 100 and includes a housing 14, a handle 26, a shroud 34 arranged on the handle 26, and a biasing member 42 is shown in
The shroud 34, in particular an outer surface 38 of the shroud 34, is biased into continuous engagement with the inner sealing edge 21 of the seal 22 via a biasing member 42, as shown in
The handle assembly 10 is adapted for use in a circuit breaker 100 as shown in
As shown in
The handle assembly 10 includes the housing 14 and the handle 26 as shown in
The front plate 15 includes the first aperture 18 through which the manually operable handle 26 extends. The handle assembly 10 includes an inner seal edge 22 that extends around the entire perimeter of the first aperture 18. The shroud 34 is arranged on the handle 26 so as to continuously engage the inner sealing edge 21 of the seal 22, which will be described in detail below. In the illustrative embodiment, inner side wall edges of first and second side walls 55, 56 of the seal 22 and inner end wall edges of first and second end walls 57, 58 of the seal 22 define the inner sealing edge 21 that engages the outer surface 38 of the shroud 34, which will be described in detail below. In other embodiments, the inner edge of the first aperture 18 may define the inner sealing edge 21.
The handle 26 extends through the first aperture 18 such that the handle 26 may be accessed by an operator in order to switch the circuit breaker 100 between at least an “ON”, “OFF”, and “TRIP” position. The handle 26 is pivotable about a pivot axis 30 located within the housing 14 and includes a handle arm 46 and an outer handle portion 50. The handle arm 46 is arranged within the housing 14 and has a first end 47 arranged within the housing 14 and a second end 48 located on an opposite end of the handle arm 46. The first end 47 is pivotably coupled to the housing 14 at a pivot point located on a pivot axis 30. The handle arm 46 is coupled to housing 14 via a rotatable fastener or the like. The handle arm 46 extends away from the pivot point towards the first aperture 18 and is attached to the outer handle portion 50 at the second end 48 of the handle arm 46.
The manually operable outer handle portion 50 is arranged on the second end 48 of the handle arm 46 and extends outwardly away from the second end 48. As can be seen in
The handle 26 is configured to pivot within a range that is delimited by the first aperture 18 as shown in
In the illustrative embodiment, the shroud 34 is coupled to the handle 26 to move with the handle 26 as shown in
The shroud 34 may be comprised of any suitable material that will keep dust, water, and other contaminants out of the interior of the housing 14 and the interior of the circuit breaker enclosure 104. In some embodiments, the shroud 34 is comprised of plastics or polymers. The shroud 34 may also be formed via injection molding, casting, 3D printing, CNC machining, or other similar processes.
As shown in
The main body 35 of the shroud 34 is mostly arranged within the housing 14 when mounted on the handle 26. In the illustrative embodiment, the main body 35 is semi-hollow and has a plurality of chambers 40 in order to reduce the weight of the shroud 34, as shown in
The shroud 34 further includes two wing portions 43, 44 that extend outwardly beyond the main body 35 in the circumferential direction as shown in
The shroud 34 further includes a central hole 66 formed in the main body 35 coaxially with the central axis 41 as shown in
In the illustrative embodiment, the shroud 34, including the main body 35 and the wings 43, 44, has a large enough circumferential extent such that, when the shroud 34 is in a centered position (as shown, for example, in
As can be seen in
In order to cause the outer surface 38 of the shroud 34 to continuously engage the inner sealing edge 21 of the seal 22, the handle assembly 10 further includes the biasing member 42 configured to pull the shroud 34 towards the outer end of the handle 26, as shown in detail in
As can be seen in
As discussed above, the seal 22 is arranged within the first aperture 18 and includes a first side wall 55, a second side wall 56, a first end wall 57, and a second end wall 58 which each project inwardly toward the outer surface 38. The first side wall 55 and the second side wall 56 each include an inner side wall edge 59, 60 that has the same contour as a circumferential contour of the outer surface 38. In other words, the radius of curvature of the inner side wall edges 59, 60 matches the radius of curvature of the outer surface 38. Likewise, the first end wall 57 and the second end wall 58 each include an inner end wall edge 61, 62 that has the same contour as the curved cross-sectional shape of the outer surface 38. The inner side wall edges 59, 60 of the first side wall 55 and the second side wall 56, and the inner end wall edges 61, 62 of the first end wall 57 and the second end wall 58 define the inner sealing edge 21 of the seal 22.
The seal 22 may be formed of a rubber-like material so as to remain in sealing contact with the outer surface 38 of the shroud 34 in the event of any imperfections in the pivoting of the handle 26. The seal 22 may further include an outer platform 70 as shown in
In operation, the handle 26 may begin in the central “TRIP” position. The shroud 34 is in contact with the inner sealing edge 21 defined by the walls 55, 56, 57, 58 of the seal 22 and is being pulled toward the outer end of the handle 26 by the biasing member 42. An operator may then grasp the outer handle portion 50, in particular the handle knob 52, and move the handle 26 to either the “ON” position or the “OFF” position so as to put the circuit breaker 100 in that mode. As the operator moves the handle 26, the outer surface 38 of the shroud 34 remains in continuous contact (engagement) with the inner sealing edge 21 because of the outer curved shape of the shroud 34 and because of the biasing member 42 pulling on the shroud 34.
In some embodiments, the handle assembly 10 may further include a lockout extension 78 as shown in
In some embodiments, the handle 26 of the handle assembly 10 may further include a safety stop 90 extending away from the outer handle portion 50 as shown in
While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. There are a plurality of advantages of the present disclosure arising from the various features of the apparatus, systems, and methods described herein. It will be noted that alternative embodiments of the apparatus, systems, and methods of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of the apparatus, systems, and methods that incorporate one or more of the features of the present invention and fall within the spirit and scope of the present disclosure as defined by the appended claims.