The invention relates generally to fusible switch assemblies, and line and load base assemblies and subcomponents thereof.
Conventional fusible switch assemblies include a line base assembly and load base assembly included within an enclosure, such as a metal switch box. Prior art fusible switch assemblies include load base assemblies including lugs adapted to allow connection to load conductor wires and clips adapted to allow connection of one or more fuses. Multi-pole, such as 3-pole, fusible switches having three fuses are commonplace.
The line base assembly of the fusible switch includes a rotor assembly having multiple blades adapted to electrically couple to stationary contacts when a rotation mechanism rotates the rotor assembly. The line base assembly also includes clips adapted to couple to a line-side end of the fuses, and a line bus connector assembly including lugs adapted to couple to line conductor wires.
However, such fusible switch assemblies, although adequate for their intended purposes, tend to be long, thus requiring relatively large enclosures, and may include high material costs. Furthermore, such switches may include multiple components. Thus, the fusible switches may tend to be costly to manufacture, because of their size and number of components.
Therefore, a need exists to reduce the size and complexity of such fusible switch assemblies.
According to a first aspect, a load base assembly is provided. The load base assembly includes a load base; and one or more fuse clip and lug assembly coupled to the load base, the fuse clip and lug assembly including: a lug body including a first lug configured to receive a first electrical wire, and a second lug configured to receive a second electrical wire, first and second slide features formed in the lug body, first and second sliding nuts configured to be received in the slide first and second slide features, and a fuse clip at least partially formed by the lug body between the first lug and the second lug.
According to another aspect, a line base assembly is provided. The line base assembly includes a line base; a line bus connector assembly coupled to the line base, the line bus connector assembly including: a single-piece connector body including a first body portion and a second body portion extending from the first body portion and being thinner than first body portion, first and second line lugs formed in the first body portion, and first and second slide features formed in the single-piece connector body, first and second sliding nuts configured to be received in the first and second slide features, and stationary contacts coupled to the second body portion; and a fuse clip assembly configured to receive a fuse, the fuse clip assembly including: a clip body including a front side, a back side, and an underside, wherein the clip body is a single piece, a fuse clip formed in the clip body having a first clip side extending from the front side to the back side and a moveable clip side, and stationary contacts attached to, and extending downward from, the underside of the clip body, and wherein the stationary contacts are positioned within a projected footprint of the clip body.
According to another aspect, a line bus connector assembly is provided. The line bus connector assembly includes a single-piece connector body including a first body portion and a second body portion extending from the first body portion and being thinner than first body portion, first and second line lugs formed in the first portion, and first and second slide features formed in the single-piece connector body, first and second sliding nuts configured to be received in the first and second slide features, and stationary contacts coupled to the second body portion.
According to another aspect, a fuse clip assembly is provided. The fuse clip assembly includes a clip body including a front side, a back side, and an underside, wherein the clip body is a single piece, a fuse clip formed in the clip body having a first clip side extending from the front side to the back side and a moveable clip side, and stationary contacts attached to, and extending downward from, the underside of the clip body, and wherein the stationary contacts are positioned within a projected footprint of the clip body.
According to another aspect, a fusible switch assembly is provided. The fusible switch assembly includes a load base assembly including a load base; and one or more fuse clip and lug assembly coupled to the load base, the fuse clip and lug assembly including: a lug body including a first lug configured to receive a first electrical wire, and a second lug configured to receive a second electrical wire, first and second load slide features formed in the lug body, first and second load sliding nuts configured to be received in each of the first and second load slide features, and a fuse clip at least partially formed by the lug body between the first lug and the second lug; and a line base assembly including: a line base, a line bus connector assembly coupled to the line base, the line bus connector assembly including: a single-piece connector body including a first body portion and a second body portion extending from the first body portion and being thinner than first body portion, first and second line lugs formed in the first portion, and first and second line slide features formed in the single-piece connector body, first and second line sliding nuts configured to be received in the first and second line slide features, and line-side stationary contacts coupled to the second body portion; and a fuse clip assembly configured to receive a fuse, the fuse clip assembly including a clip body including a front side, a back side, and an underside, wherein the clip body is a single piece, a fuse clip formed in the clip body having a first clip side extending from the front side to the back side and a moveable clip side, and load-side stationary contacts attached to, and extending downward from, the underside of the clip body, and wherein the stationary contacts are positioned within a projected footprint of the clip body.
According to another aspect, a fuse clip and lug assembly is provided. The fuse clip and lug assembly includes a lug body including a first lug configured to receive a first electrical wire, and a second lug configured to receive a second electrical wire, first and second slide features formed in the lug body, first and second sliding nuts configured to be received in the slide first and second slide features, and a fuse clip at least partially formed by the lug body between the first lug and the second lug.
According to another aspect, a fuse clip assembly is provided. The fuse clip assembly includes a body, a fuse clip at least partially formed by the body, the fuse clip including a first clip side and a moveable clip side and at least one slot formed therein, the moveable clip side including a spring member, and a fuse rejection element including a crossbar that registers in the slot formed in the fuse clip.
According to another aspect, a method of operating a line base assembly is provided. The method includes providing a line base assembly including a line bus connector assembly and a fuse clip assembly, the line bus connector assembly including a single-piece connector body having a first body portion and a second body portion, and line-side stationary contacts coupled to the second body portion, the fuse clip assembly including a clip body, a fuse clip formed in the clip body having a first clip side extending from a front side to a back side and a moveable clip side, and load-side stationary contacts attached to, and extending downward from, the underside of the clip body, and wherein the load-side stationary contacts are positioned within a projected footprint of the clip body, providing a rotor assembly including first blades and second blades, and rotating the rotor assembly to engage the first blades with the line-side stationary contacts and the second blades with the load-side stationary contacts underneath the projected footprint of the clip body.
Still other aspects, features, and advantages may be readily apparent from the following description wherein a number of example embodiments are described and illustrated, including the best mode contemplated for carrying out the invention. The invention may be capable of other embodiments, and its several details may be modified, all without departing from the scope of the invention. Accordingly, the drawings and descriptions are to be regarded as illustrative in nature, and not as restrictive. The drawings are not necessarily drawn to scale. The invention covers all modifications, equivalents, and alternatives falling within the scope of the invention.
Reference will now be made in detail to the example embodiments of this disclosure, which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
The aforementioned problem of excessive size and complexity is overcome by embodiments of the invention. In particular, fusible switch assemblies including line base assemblies and load base assemblies are described herein. Subassemblies and components thereof such as fuse clip assemblies, fuse clip and lug and assemblies, and line bus connector assemblies described herein aid in the provision of a compact construction resulting in substantially shorter component length, and fewer components.
Embodiments of fusible switch assemblies, line base assemblies, load base assemblies and components thereof will be explained in greater detail below with reference to
Load Base Assembly
Coupling attachment to the enclosure 911 may be made by connection features 202C of the load base 202, such as two or more tabs shown that receive fasteners (not shown). Other numbers of tabs or types of connection features 202C may be used. Load base 202 may be made of any suitable insulating material, for example a polymer insulating material such as a thermoset plastic (e.g., polyester material). The thermoset plastic may be mineral filled, glass-reinforced, or both. Load base assembly 200 may also include one or more fuse clip and lug assemblies 205A-205C that may be attached to the load base 202, such as by fasteners 207 (e.g., screws, bolts, or the like). Fuse clip and lug assemblies 205A-205C may be identical to each other in their construction, as will be described with reference to
Load base 202 may include one or more barriers 210 that separate the poles from one another. Barriers 210 may be received and secured in slots 204S formed in the sides and/or top of the body of the load base 202. In the depicted embodiment, the barriers 210 may be included in a barrier assembly 212 including the barriers 210 and an interconnecting bridge 212B. Interconnecting bridge 212B may include one or more base registration features 212F (e.g., one or more holes) that may register on one or more bosses 202B formed on the upper surface of the body of the load base 202. Other suitable registration features may be used.
Fuse Clip and Lug Assembly
Now referring to
Fuse clip and lug assembly 205B includes a first lug 316 formed in the lug body 314 that is configured to receive a first load-side electrical wire (not shown). A second lug 318 may also be formed in the lug body 314 and may be configured to receive a second load-side electrical wire (not shown). First lug 316 and second lug 318 may each be sized and configured to receive a conductor wire having a size between about 1/0 AWG and about 600 kcmil that may be suitable for a 400 A-600 A fusible switch assembly, such as fusible switch assembly 900 (
First and second slide features 320, 322, which may comprise opposing grooves formed in and extending from front to back into the lug body 314, may be provided above semi-circular portions of each of the first lug 316 and the second lug 318. Grooves may be about 0.13 inch deep (about 3.3 mm deep) and about 0.31 inch high (about 7.9 mm high) and extend from front to back. Other sized grooves may be used. Any suitably shaped groove may be used. First and second sliding nuts 324, 326 are configured to be slidably received in each of the first and second slide features 320, 322, respectively. First and second sliding nuts 324, 326 may include edges that are configured to slide in the first and second slide features 320, 322.
One end of the first and second sliding nuts 324, 326 may include one or more stops 320S, 322S that interface with and abut the lug body 314 and function to limit an amount of insertion of the first and second sliding nuts 324, 326 into the first and second slide features 320, 322. First and second sliding nuts 324, 326 may include a threaded bore that receives first and second wire fastener 328, 330, such as a hex head set screw shown. Other suitable wire fasteners may be used.
Fuse clip and lug assembly 205B also includes a fuse clip 332 at least partially formed by the lug body 314 and that may be centrally located between the first lug 316 and the second lug 318. Fuse clip 332 is configured and adapted to receive a fuse 308 including a fuse tang 308T as shown in
In one or more embodiments, the fuse clip 332 may optionally include an anti-walkout feature 339. Anti-walkout feature 339 may include a lip formed on a portion of the lug body 314, such as on an upper end of the first clip side 334, and may be configured to prevent the tang 308T of the fuse 308 that is receivable in the fuse clip 332 from unwanted exiting (e.g., walking out of the fuse clip 332) due to vibration caused by system operation or other forces. The lip may extend beyond a surface of the first clip side 334 by a lip distance “d” which may be between about 0.02 (about 0.5 mm) and about 0.04 inch (about 1 mm), for example. The lip may include a radius, and may extend from front to back, as shown. The anti-walkout feature 339 will only allow the tang 308T to move out of the fuse clip 332 a defined distance before the tang 308T and anti-walkout feature 339 make contact with one another, further limiting the movement of the tang 308T. Enough side-to-side clearance is allotted in the fuse clip 332 to allow a user to insert or remove the fuse 308 by slightly rotating the fuse 308 in the fuse clip 332 to move around the tang 308T around the anti-walkout feature 339.
In one or more embodiments, the fuse clip 332 may include a fuse rejection feature. Fuse rejection feature may be included to reject certain types of fuses (e.g., all but class R fuses). Fuse rejection feature in some embodiments may be as shown in
The support surface 314S may include a domed portion (e.g., a truncated cylindrical dome), which may have a dome radius of about 1.25 inch (about 32 mm) and may be spaced from a back surface of the spring member 338 (e.g., leaf spring) by a gap 338G of between about 0.06 inch (about 1.5 mm) and about 0.12 inch (about 3 mm). This gap 338G and support surface 314S may be used to prevent plastic deformation (yielding) of the spring member 338, and may allow only elastic deformation thereof.
As shown, the underside of the lug body 314 may include a planar surface 314P including threaded bores 314B configured to receive fasteners 207 (
Line Base Assembly
Line base assembly 400 is operational to receive and secure line wire conductors (not shown) at the line bus connector assembly 444 and pass current to the fuse 408, and also allow electrical disconnection/connection via rotation of the rotor assembly 448 as will be apparent from the following. Two or three of the line base assemblies 400 shown in
For example, a 400 Amp, 3-pole line base switch assembly 700 may include 3 poles and a line base assembly 400 per pole. One of the stationary contacts per pole may be inactive (or even not included). A 400 Amp, 2-pole line base switch assembly may include 2 poles and a line base assembly 400 per pole, with one of the stationary contacts being inactive. In this version, a line base 742 may be used, but the center pole region would be unused. A 600 Amp, 3-pole line base switch assembly (e.g., line base switch assembly 700 as shown) may include 3 poles and a line base assembly 400 per pole. A 600 Amp, 2-pole line base switch assembly may include 2 poles and a line base assembly 400 per pole. In this version, a common line base 742 may be used, but the center pole region would be unused.
Line Bus Connector Assembly
In more detail, and referring to
The single-piece connector body 555 includes a first body portion 560 and a second body portion 562 extending from the first body portion 560 on a side opposite a line wire conductor entry side. A height of the second body portion 562 is thinner than a height of the first body portion 560. Second body portion 562 may include a same thickness throughout, and include a planar upper surface. Line bus connector assembly 444 includes stationary contacts 564A-564C (otherwise referred to herein as “line-side stationary contacts”) attached to the second body portion 562, such as by fasteners 569 (e.g., bolts or screws or the like). Other fastening methods may be used. Stationary contacts 564A-564C may be made of a copper material, may be bent in an L-shape, and may include pointed tips thereon, as shown.
In some embodiments, an outer contour configuration of the first body portion 560 and the second body portion 562 of the line bus connector assembly 444 may be extruded. Thus, an extruded component including the structure and contours of the first and second body portions 560, 562 may be formed in the extrusion direction 555E. The extrusion may be cut to the overall length of the line bus connector assembly 444, and then machined to form the final features of the first and second body portions 560, 562, including forming of the first and second line lugs 556, 558, slide features for the sliding nuts 524, 526, the first hole 557A and second hole 557B and threaded bores that receive the fasteners 569. This manufacturing process may result in substantially reduced material and manufacturing cost.
Fuse Clip Assembly
Referring now to
The clip body 665 may include a first flange 668 and a second flange 670 extending in opposite lateral directions. Registration features 672A, 672B may be provided on the first flange 668 and the second flange 670, such as on the terminal ends thereof, and may register with another feature formed on the line base 442 (
The stationary contacts 664A-664C may be attached and positioned in line with the fuse clip 667 formed in the clip body 665 as shown, i.e., connected directly under a projected footprint of the clip body 665 projecting from the underside 665U, wherein the footprint is outlined by the terminal ends of the flanges 668, 670 and the front and back sides 665F, 665B of the clip body 665. Thus, the stationary contacts 664A-664C are all substantially aligned underneath the fuse clip 667 when viewed from the side (in a direction from first flange 668 to second flange 670). Thus, the fuse clip assembly 446 exhibits a shorter front-to-back profile than prior art fuse clip assemblies, thus shortening the overall length of the line base switch assembly 700 (
Line Base Switch Assembly
A line base switch assembly 700 including 3 poles, namely first pole 776, second pole 777, and third pole 778 are shown in
As is shown in
Each of the blades 881, 882 of the rotor assembly 448 may include blade spacers 884 located in between the individual blades to keep them spaced apart, as desired. Blade spacers 884 may be annular rings. Blade springs 885 may be added to apply a force to ensure proper electrical contact when the rotor assembly 448 is rotated to make contact with and receive the stationary contacts 564A-564C of the line bus connector assembly 444 between the first blades 881, and the stationary contacts 664A-664C of the fuse clip assembly 446 between the second blades 882. Other suitable constructions of the rotor assembly 448 may be used. Some or the blades 881, 882 may be omitted in 400 A versions, as well as in 2-pole versions of the line base switch assembly.
The method 1000 includes, in 1004, providing a rotor assembly (e.g., rotor assembly 448) including first blades (e.g. blades 881) and second blades (e.g., second blades 882), and, in 1006, rotating the rotor assembly to engage the first blades with the line-side stationary contacts and the second blades with the load-side stationary contacts underneath the projected footprint of the clip body.
It should be readily appreciated by those persons skilled in the art that the invention is susceptible of broad utility and application. Many embodiments and adaptations of the invention other than those described herein, as well as many variations, modifications, and equivalent arrangements, will be apparent from, or reasonably suggested by, the invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the invention has been described herein in detail in relation to specific embodiments, it is to be understood that this disclosure is only illustrative and presents examples of the invention and is made merely for purposes of providing a full and enabling disclosure of the invention. This disclosure is not intended to limit the invention to the particular devices, systems or methods disclosed, but, to the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention.
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Number | Date | Country | |
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20160079687 A1 | Mar 2016 | US |