1. Field of the Invention
The invention relates generally to electrical switching apparatus and, more particularly, to charging assemblies for electrical switching apparatus, such as circuit breakers. The invention also relates to charging handles for circuit breaker charging mechanisms.
2. Background Information
Electrical switching apparatus, such as circuit breakers, provide protection for electrical systems from electrical fault conditions such as, for example, current overloads, short circuits, abnormal voltage and other fault conditions. Typically, circuit breakers include an operating mechanism which opens electrical contact assemblies to interrupt the flow of current through the conductors of an electrical system in response to such fault conditions.
Many low-voltage circuit breakers, for example, employ a molded housing having a cover. The operating mechanism for such circuit breakers is structured to open and close separable electrical contacts, which are enclosed by the molded housing. More specifically, the operating mechanism includes a charging assembly having a close spring and a charging handle. The close spring stores energy for closing the circuit breaker, and is charged by pulling the charging handle a number of times. When the charging handle is not being employed, it is typically stowed in an upright position within a recess in the cover of the circuit breaker housing, and is held there by a handle return spring. Low-voltage circuit breakers and charging assemblies therefor are described, in detail, for example, in U.S. Pat. Nos. 5,938,008, 6,064,021, and 6,160,234, which are incorporated herein by reference.
It can be difficult for an operator to gain the necessary access to the charging handle (e.g., insert a finger underneath the handle) to remove (e.g., pivot it far enough with respect to the housing cover) it from the recess and have access to a sufficient portion of the charging handle to grasp it and begin the charging operation. Additionally, known charging handles for charging circuit breaker operating mechanisms tend to be relatively narrow, and often have relatively abrupt (e.g., sharp) edges. This can cause discomfort to the operator when the operator pulls on the handle and experiences the load associated with charging the breaker. These disadvantages are particularly pronounced in view of the market trend toward smaller circuit breakers. Specifically, the relatively small size of circuit breakers inhibits the ability to quickly, easily and relatively comfortably operate the user interface features of the circuit breaker, including the charging handle. Added to this is the fact that the individuals (e.g., without limitation, electricians) who typically operate the circuit breakers sometimes prefer or insist on wearing work gloves, which can make manipulation of the charging handle very difficult.
In an attempt to overcome this disadvantage, one prior proposal has been to include a molded finger recess in the cover of the circuit breaker housing. Specifically, a recess is provided as a molded feature extending from the outer surface of the housing cover and protruding into the interior of the housing. The recess is intended to be deep enough for the operator to reach his or her finger underneath the end of the charging handle. However, this undesirably results in the recess protruding a significant distance into the interior of the circuit breaker housing and taking up valuable space therein. Another disadvantage is that such recesses tend to favor either right-handed or left-handed operators by providing access to only one of the left and right sides of the charging handle. See, e.g., U.S. Pat. Nos. 5,938,008, 6,064,021, and 6,160,234 (each showing a recess for a charging handle which provides access only to the right side of the charging handle).
There is, therefore, room for improvement in electrical switching apparatus, such as circuit breakers, and in charging assemblies and charging handles therefor.
These needs and others are met by embodiments of the invention, which are directed to an optimized charging handle for a charging assembly of an electrical switching apparatus. Among other benefits, the charging handle has a maximum length and associated mechanical leverage, offers improved accessibility by an operator, and has an ergonomic and user-friendly design.
As one aspect of the invention, a charging handle is provided for an electrical switching apparatus. The electrical switching apparatus includes a housing having an exterior, an interior and a recess extending from the exterior toward the interior, separable contacts enclosed by the housing, an operating mechanism structured to open and close the separable contacts, and a charging assembly. The charging handle comprises: a first end structured to be coupled to the charging assembly within the interior of the housing; a second end disposed opposite and distal from the first end and including a finger pull; and an elongated body extending between the first end and the second end, the elongated body including a first side, a second side, an inner surface structured to extend toward the interior of the housing, and an outer surface disposed opposite the inner surface. The charging handle is movable among a first position in which the elongated body is structured to be disposed generally within the recess of the housing, and a second position in which the second end of the charging handle is structured to extend outwardly from the recess of the housing. The finger pull is disposed on the outer surface of the elongated body at or about the second end of the charging handle, in order that the finger pull is readily accessible from all of: the second end of the charging handle, the first side of the elongated body of the charging handle, and the second side of the elongated body of the charging handle.
The finger pull may comprise a protrusion extending outwardly from the outer surface of the elongated body of the charging handle at or about the second end of the charging handle. The finger pull may further comprise a pocket extending inwardly from the outer surface of the elongated body of the charging handle toward the inner surface of the elongated body of the charging handle at or about the second end of the charging handle. The elongated body of the charging handle may have a first axis, and the protrusion may have a second axis, wherein the first axis of the charging handle and the second axis of the protrusion intersect at an angle. The angle may be less than 90 degrees, in order that the protrusion of the finger pull overlays at least a portion of the pocket of the finger pull.
As another aspect of the invention, a charging assembly is provided for an electrical switching apparatus. The electrical switching apparatus includes a housing having an exterior, an interior and a recess extending from the exterior toward the interior, separable contacts enclosed by the housing, and an operating mechanism structured to open and close the separable contacts. The charging assembly comprises: a spring coupled to the operating mechanism, the spring being structured to be chargeable in order to cause the operating mechanism to close the separable contacts; and a charging handle structured to charge the spring, the charging handle comprising: a first end structured to be coupled to the charging assembly within the interior of the housing, a second end disposed opposite and distal from the first end and including a finger pull, and an elongated body extending between the first end and the second end, the elongated body including a first side, a second side, an inner surface structured to extend toward the interior of the housing, and an outer surface disposed opposite the inner surface. The charging handle is movable among a first position in which the elongated body is structured to be generally disposed within the recess of the housing, and a second position in which the second end of the charging handle is structured to extend outwardly from the recess of the housing. When the charging handle is moved from the first position toward the second position, the spring of the charging assembly of the operating mechanism is charged. The finger pull is disposed on the outer surface of the elongated body at or about the second end of the charging handle, in order that the finger pull is readily accessible from all of: the second end of the charging handle, the first side of the elongated body of the charging handle, and the second side of the elongated body of the charging handle.
As another aspect of the invention, an electrical switching apparatus comprises: a housing including an exterior, an interior, and a cover comprising a recess, the recess of the cover extending from the exterior of the housing toward the interior of the housing; separable contacts enclosed by the housing; an operating mechanism structured to open and closed the separable contacts; and a charging assembly comprising: a spring coupled to the operating mechanism, the spring being chargeable in order to cause the operating mechanism to close the separable contacts, and a charging handle comprising: a first end coupled to the charging assembly within the interior of the housing, a second end disposed opposite and distal from the first end and including a finger pull, and an elongated body extending between the first end and the second end, the elongated body including a first side, a second side, an inner surface extending toward the interior of the housing, and an outer surface disposed opposite the inner surface. The charging handle is movable among a first position in which the elongated body is generally disposed within the recess of the cover of the housing, and a second position in which the second end of the charging handle extends outwardly from the recess of the cover of the housing. When the charging handle is moved from the first position toward the second position, the spring of the charging assembly of the operating mechanism is structured to be charged. The finger pull is disposed on the outer surface of the elongated body at or about the second end of the charging handle, in order that the finger pull is readily accessible from all of: the second end of the charging handle, the first side of the elongated body of the charging handle, and the second side of the elongated body of the charging handle.
The cover of the housing may have a first depth, and the recess of the cover may have a second depth, wherein the second depth of the recess is substantially less than the first depth of the cover of the housing, in order to minimize the amount of space occupied by the recess within the interior of the housing. The cover of the housing may further comprises a finger well, wherein the finger well extends from the exterior of the housing toward the interior of the housing and has a third depth. The third depth of the finger well may be substantially less than the second depth of the recess.
The recess may have a first end and a second end disposed opposite and distal from the first end. The first end of the charging handle may be disposed within the first end of the recess. When the charging handle is disposed in the first position, the second end of the charging handle may be substantially disposed within the second end of the recess. The finger well may be a concave arcuate indentation in the cover of the housing, wherein the concave arcuate indentation is disposed at or about the second end of the recess. The second end of the charging handle may extend beyond the concave arcuate indentation.
As another aspect of the invention, an electrical switching apparatus comprises: a housing including an exterior, an interior, and a cover comprising a recess, the recess of the cover extending from the exterior of the housing toward the interior of the housing; separable contacts enclosed by the housing; an operating mechanism structured to open and close the separable contacts; and a charging assembly comprising: a spring coupled to the operating mechanism, the spring being chargeable in order to cause the operating mechanism to close the separable contacts, and a charging handle comprising: a first end coupled to the charging assembly within the interior of the housing, a second end disposed opposite and distal from the first end and including a finger pull, and an elongated body extending between the first end and the second end, the elongated body including a first side, a second side, an inner surface extending toward the interior of the housing, and an outer surface disposed opposite the inner surface. The charging handle is movable among a first position in which the elongated body is generally disposed within the recess of the cover of the housing, and a second position in which the second end of the charging handle extends outwardly from the recess of the cover of the housing. When the charging handle is moved from the first position toward the second position, the spring of the charging assembly of the operating mechanism is charged. The finger pull is disposed on the outer surface of the elongated body at or about the second end of the charging handle. The cover of the housing provides access to the finger pull from the second end of the charging handle, to both the first side of the elongated body of the charging handle and the second side of the elongated body of the charging handle.
A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:
For purposes of illustration, embodiments of the invention will be described as applied to a charging handle for the charging assembly of an operating mechanism for a low-voltage circuit breaker, although it will become apparent that they could also be applied to any known or suitable electrical switching apparatus (e.g., without limitation, circuit switching devices and circuit interrupters such as circuit breakers other than low-voltage circuit breakers, network protectors, contactors, motor starters, motor controllers and other load controllers).
Directional phrases used herein, such as, for example, left, right, top, bottom, upper, lower, front, back, clockwise, counterclockwise and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting to the claims unless expressly recited therein.
As employed herein, the terms “fastener” and “fastening mechanism” refer to any suitable connecting or tightening material or device expressly including, but not limited to, rivets (e.g., without limitation, pop rivets), screws, bolts and the combinations of bolts and nuts (e.g., without limitation, lock nuts) and bolts, washers (e.g., without limitation, lock washers) and nuts.
As employed herein, the statement that two or more parts are “coupled” together shall mean that the parts are joined together either directly or joined through one or more intermediate parts.
As employed herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality).
The charging assembly 20 includes a spring, indicated generally by reference number 22 in
The charging handle 24 is movable among a first position in which the elongated body 32 of the charging handle 24 is generally disposed within the recess 12 of the housing cover 10, as shown in
As shown in
To still further facilitate operation of the charging handle 24, the example finger pull 30 includes a protrusion 42, which extends outwardly from the outer surface 40 of the elongated body 32 of the charging handle 24 at or about the second end 28 of the charging handle 24, and/or a pocket 44, which extends inwardly from the outer surface 40 toward the inner surface 38. The example charging handle 24 includes both the protrusion 42 and the pocket 44, although it will be appreciated that it could alternatively have only one or the other (not shown) or any suitable alternative combination (not shown) of both. As best shown in
Continuing to refer to
A still further advantage of the disclosed low-voltage circuit breaker 2, and charging assembly 20 and charging handle 24 therefor, is the fact that the recess 12 in the cover 10 of the circuit breaker housing 4 occupies relatively little space within the interior 8 of the housing 4. More specifically, as best shown in
Continuing to refer to
Referring to
Accordingly, it will be appreciated that the disclosed charging handle 24 (
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/890,209, filed Feb. 16, 2007.
Number | Name | Date | Kind |
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5274206 | Milianowicz | Dec 1993 | A |
5938008 | Wehrli, III et al. | Aug 1999 | A |
6054655 | Rudolph et al. | Apr 2000 | A |
6064021 | Wehrli et al. | May 2000 | A |
6160234 | Wehrli et al. | Dec 2000 | A |
Number | Date | Country | |
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20080197003 A1 | Aug 2008 | US |
Number | Date | Country | |
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60890209 | Feb 2007 | US |