The subject matter disclosed herein relates to circuit interrupting or switching devices. More specifically, an aspect of the invention relates to switching devices that include a mechanism and method of reducing or preventing distortion and destruction of a housing of the switching device through a reinforced housing.
As is known to those skilled in the art, various switching devices are currently available and may be used for interrupting or breaking an electrical current between a source of electrical power and a load. Typically, switching devices have an “ON” and an “OFF” state, where in the ON state, the switching device establishes an electrical connection between contacts and allows electrical current to flow through the switching device from a power source to an electrical load. In the OFF state, the switching device opens, or breaks, the electrical connection between contacts, preventing the electrical current from flowing through the switching device. These switching devices may take the form of circuit breakers, contactors, relays, motor starters and the like. Upon opening or separating the contacts, an electrical arc may be generated. The switching device further must be able to withstand electrical arcs, and short circuits, multiple times in order to be certified for use. The generation of the electrical arc and/or short circuits result in an increase in temperature and pressure inside the switching device which may damage, the contacts of the switching device, the device itself, or the load that is being protected.
While there have been various approaches to improve extinguishing an arc in a circuit interrupter or reducing damage, there is a need for further improvement in the containment of the arc pressure generated as a result of the circuit interruption event to prevent damage to the switching device.
The invention relates to a switching device for industrial equipment. According to one embodiment of the invention, the switching device includes a housing having a front housing and a rear housing that couple to form the housing. The rear housing includes a rear housing face, a first sidewall, a second sidewall, a first end wall, and a second end wall. The second sidewall is located opposite the first sidewall, and the second end wall is located opposite the first end wall. Each of the first sidewall, second sidewall, first end wall, and second end wall extend from the rear housing face to define at least one interior chamber therebetween. A rear housing tab extends from the first sidewall of the rear housing. The switching device further includes a splitter plate support that is located within the at least one interior chamber. The splitter plate support includes a first support panel, and the first support panel includes an outer panel face configured to be orientated so that it is adjacent to the first sidewall of the rear housing. The first support panel further includes a support hook that extends from the outer panel face. The rear housing tab engages the support hook to, at least in part, connect the first support panel to the first sidewall of the rear housing.
According to another embodiment of the invention, a switching device for industrial equipment includes a housing having a front housing configured to be mounted to a rear housing. A rear housing tab extends from the rear housing toward the front housing. The switching device also includes a splitter plate support having a first support panel. The first support panel includes an aperture, and the rear housing tab is configured to extend through the aperture when the splitter plate support is mounted with the rear housing.
According to still another embodiment of the invention, a method of reinforcing side walls of a housing of a switching device for industrial equipment is disclosed. A splitter plate support is inserted into a rear housing of the switching device in which a way that a support hook of the splitter plate support engages with a rear housing tab, where the rear housing tab extends from a side wall of the rear housing. The rear housing is mounted to the front housing so that a sidewall of the front housing extends over the rear housing tab and support hook. The sidewall of the front housing is generally coplanar with the sidewall of the rear housing when the front housing is mounted to the rear housing, and the sidewalls of the front housing and of the rear housing define a sidewall of the housing of the switching device.
These and other advantages and features of the invention will become apparent to those skilled in the art from the detailed description and the accompanying drawings. It should be understood, however, that the detailed description and accompanying drawings, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.
Various exemplary embodiments of the subject matter disclosed herein are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout, and in which:
In describing the various embodiments of the invention Which are illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word “connected,” “attached,” or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.
The various features and advantageous details of the subject matter disclosed herein are explained more fully with reference to the non-limiting embodiments described in detail in the following description.
The subject matter disclosed herein describes a reinforced housing of a switching device for containment of arc pressure generated as a result of a circuit interruption event to prevent damage to the switching device. The housing of the switching device includes a front housing and a rear housing and is reinforced through the engagement of a support panel with the rear housing. A rear housing tab extending from the rear housing engages with a support panel of a splitter plate support. The splitter plate support extends from the splitter plate for engagement with the rear housing tab. The splitter plate support includes a hook with an aperture extending through the hook. The rear housing tab extends through the aperture located within the hook, and the rear housing tab and support hook engagement prevent lateral movement between the sidewall of the rear housing and the sidewall of the front housing. Additionally, the sidewall of the front housing extends over a portion of the sidewall of the rear housing and the two sidewalls are generally coplanar when front housing is mounted to the rear housing. Thus, not only does the engagement of the rear housing tab and support hook resist lateral movement of the sidewalls of the rear housing with respect to the front housing during short circuit events, the overlapping rear housing and support panel further form a double-walled region within at least one region of the housing to further reinforce the housing. The reinforced housing is therefore better able to withstand pressure resulting from short circuit events and reduce the likelihood of damage to the switching device.
Terms such as upper, lower, inner, outer, front, rear, left, right, and the like will be used herein with respect to an illustrated switching device 5 as shown in
Referring to
The housing 10 may further include a Deutsches Institut fur Normung (DIN) slot 45 located and positioned at the bottom face 20. The DIN slot 45 is an indention shaped and sized so that a DIN rail (not shown) may engage the DIN slot 45 to allow the switching device 5 to be mounted and secured within a cabinet (not shown). The housing 10 further includes a front housing 50 and a rear housing 100 which couple to form the housing 10. The front housing 50 is located towards the front of the housing 10, while the rear housing 100 is located near the back of the housing 10.
The front housing 50 includes a front housing face 55 (forming the top face 15 of the housing 10), a first sidewall 60 (forming a portion of the sidewall 25), a second sidewall 65 (forming a portion of the sidewall 30), a first end wall 70 (forming a portion of the end wall 35), and a second end wall 75 (forming a portion of the end wall 40). The first 60 is located opposite to a second sidewall 65, and the first end wall 70 is located opposite to the second end wall 75. The sidewalls 60, 65 and end walls 70, 75 all extend away from the front housing face 55 to form the front housing 50, a shell or portion of the housing 10. Similarly, the rear housing 100 also includes a rear housing face 105 (which forms the bottom face 20), a first sidewall 110 (forming a portion of the sidewall 25), a second sidewall 115 (forming a portion of the sidewall 30), a first end wall 120 (forming a portion of the end wall 35), and a second end wall 125 (forming a portion of the end wall 40). The sidewalls 110, 115 and end walls 120, 125 form a perimeter around the rear housing face 105 and extends therefrom to form an interior chamber 128 within the rear housing 100.
Thus, together, the first sidewalls 60, 110 of the front and rear housings 50, 100 form the first sidewall 25 of the housing 10, the second sidewalls 65, 115 of the front and rear housings 50, 100 form the second sidewall of the housing 10, the first end walls 70, 120 of the front and rear housings 50, 100 form the first end wall 35 of the housing 10, and the second end walls 75, 125 of the front and rear housings 50, 100 form the first end wall 40 of the housing 10. The front housing 50 and rear housing 100 overlap for at least a short distance where they join and may engage each other in a snap connection. Alternately, or in combination with the snap connection, the front housing 5 and rear housing 100 may couple through other methods in various embodiments of the invention such as a friction fit or with a mechanical coupler such as a screw.
The switching device 5 further includes an actuator 200 that extends through the front housing face 50 and is configured to engage a plunger (not shown) which moves in a back-and-forth motion along an axis thereby allowing the plunger to move between a first position and a second position so that the switching device 5 moves between a corresponding first state and a second state. In a first state, the contacts are closed or adjacent to each establishing an electrical connection. In the second state, the contacts are open or separated to break the electrical connection between the contacts. The actuator 200 may be manually activated by, for example, a toggle switch or a handle 205 on a rotary switch 210.
As seen in
The first support panel 305 includes a support hook 315 through which the rear housing tab 130 extends thereby allowing the first support panel 305 and the sidewall 110 of the rear housing 100 to engage each other. The engagement of the first support panel 305 and sidewall 110 through the rear housing tab 130 and support hook 315 reinforces the sidewall 25 of the housing by creating a double-walled portion in at least one region of the sidewall 25 of the housing 10.
In more detail, and as illustrated in
Turning to
In more detail and, although only the first support panel 305 is described, the second support panel 310 may be a mirror image of the first support panel 305, the first support panel 305 may be generally divided into a first panel region 330, a center panel region 335, and second panel region 340. The center panel region 335 may be located and positioned between the first panel region 330 and the second panel region 340. The first support panel 305 includes an inner panel face 345 and an outer panel face 350, located opposite from the inner panel face 345. The inner panel face 345 and outer panel face 350 both further extend across the regions 330, 335, and 340. The first support panel 305 further includes an upper edge 355 extending between the panel faces 345, 350, as well as a lower edge 360 located opposite from the upper edge 355 and also extending between the panel faces 345, 350. The first support panel 305 also has a first side edge 365 and a second side edge 370, located opposite from the first side edge 365,
The first support panel 305 further includes a series of slits 375 forming gaps located extending from the first side edge 365 along a portion of the first panel region 330 toward the center panel region 335. Additional slits 375 for gaps and are located extending from the second side edge 370 along a portion of the second panel region 340 towards the center panel region 335. The first support panel 305, therefore, includes slits 375 in at least a portion of its first and second regions 330, 340. As mentioned previously, the first support panel 305 has support members 328, which are located between the slits 375 at both the side edges 365, 370 and further project generally perpendicularly from the inner panel face 345 and towards the other panel 305, 310. When the first support panel 305 and second support panel 310 are engaged to form the splitter plate support 300, splitter plates (not shown) may be inserted into slots defined, at least in part, by the slits 375 of the first and second support panels 305, 310 and held between consecutive support members 328. The support members 328 position and retain the splitter plates within the slots or slits 375 of the panels 305, 310.
The first support panel 310 further includes the support hook 315 which has an arm portion 380 that extends into a hook portion 385. The support hook 315 has an inner surface 390, extending the length of the support hook 315, and an outer surface 395 located opposite to the inner surface 390. The support hook 315 further includes a support aperture 400 at and extending through the hook portion 385. The support aperture 400 further creates an aperture rim 405 extending around the support aperture 400. As illustrated, the support hook 315 is located at the center panel region 335, with the inner surface 390 of the support hook generally coplanar with the inner panel face 345, the outer surface 395 generally coplanar with the outer panel face 350, and the support hook 315 protruding upward past the upper edge 355 of the support panel 305.
The support hook 315 is configured to engage the rear housing tab 130 of the rear housing 100 to reinforce at least a portion of the rear housing 10, as illustrated in
To engage the first support panel 305 with the rear housing 100, the rear housing tab 130 may be inserted so that the rear housing tab 130 extends through the support aperture 400. Once the rear housing tab 130 has been inserted into the support aperture 400, the outer surface 136 of the rear housing tab 130 is adjacent and abuts the aperture rim 405, as well as the inner surface 390 of the support hook 315, to prevent lateral movement of the rear housing tab 130 and support hook 315 between the sidewall 110 of the rear housing 100 and the sidewall 60 of the front housing 50. The sidewall 110 of the rear housing 100 and the sidewall 60 of the front housing 50 are further generally coplanar to each other when the sidewall 60 of the front housing 50 extends over the rear housing tab 130 and the support hook 315 as the front housing 50 is mounted or coupled to the rear housing 100. Thus, not only does the engagement of the rear housing tab 130 and support hook 315 ensure that there is no lateral movement of the sidewalls 60, 110 during short circuit events, the overlapping rear housing 100 and support panel 305 further form a double-walled region within at least one region of the housing 10 to further reinforce the housing 10.
Under normal operation, the switching device 5 is configured to selectively open and close a pair of electrical contacts. The electrical contacts are located within an arc chamber defined, at least in part, between opposing support plates 305, 310. When contacts are separated under load, an arc is generated between the two contacts as the contacts separate. The splitter plates (not shown) supported by the support plates 305, 310 are configured to draw the arc toward the plates and to rapidly extinguish the arc.
Under fault conditions, however, such as a short circuit or ground fault condition in a load being supplied power via the switching device 5, the amount of current can be many times greater than the amount of current expected under normal operation. The arc generated while opening contacts under a fault condition can result in plasma generation within the arc chamber, rapidly increasing the temperature and pressure within the arc chamber. Although the splitter plates are configured to conduct and help extinguish the arc and the slits 375 in the support panels 305, 310 are configured to vent the pressure built up within the arc chamber, the rapid increase in temperature and pressure may exceed the ability of the splitter plates to extinguish the arc and the ability of the slits 375 to vent the excess pressure. Under prior designs of the switching device 5, the sidewall 110 of the rear housing 100 would be deflected outward as a result of the excess temperature and pressure built up in the arc chamber.
The present invention reinforces the sidewall 110 of the rear housing 100 to prevent lateral deflection under the afore-described fault condition. The rear housing tab 130 extends through the aperture 400 in the support hook 315. Thus, when pressure is vented through the slits 375 of the support panels 305, 310 and within the interior chamber 128 of the rear housing 100, the pressure exerts an outward force on the sidewalls 110, 115 of the rear housing 100. The outward force on the sidewall, however, causes the outer surface 136 of the rear housing tab 130 to engage the support hook 315, preventing lateral motion of the sidewall 110 away from the support panel 305, 310 to which the sidewall 110 is engaged. Because the rear housing tab 130 is engaged with the aperture 400 in the support hook 315, the combined strength of both the support panel 305, 310 and the sidewall 110 resist lateral motion of the housing 10, allowing the housing 10 of the switching device 5 to survive the arc generated under the fault condition.
It should be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth herein. The invention is capable of other embodiments and of being practiced or carried out in various ways. Variations and modifications of the foregoing are within the scope of the present invention. It also being understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.
In the preceding specification, various embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the broader scope of the invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense.
Number | Name | Date | Kind |
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7964811 | Lin | Jun 2011 | B2 |
9704676 | Cardwell | Jul 2017 | B1 |
10056210 | Marzano | Aug 2018 | B2 |
10840035 | Strebel Marzano et al. | Nov 2020 | B1 |
Number | Date | Country |
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103 56 270 | Jun 2005 | DE |
Entry |
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Extended European Search Report dated Feb. 10, 2023; Application No. 22196338.2—(10) pages. |
Number | Date | Country | |
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20230088972 A1 | Mar 2023 | US |