Embodiments of the invention relate generally to standby generators and, more particularly, to an alternator adapter for use in a standby generator.
Engine-driven, electrical generators are used in a wide variety of applications. Typically, an electrical generator utilizes a single driving engine directly coupled to a generator or alternator through a common shaft. Upon activation of the generator, a fuel and air mixture is provided to the combustion chambers of corresponding cylinders of the engine. The fuel mixture in each combustion chamber is ignited, thereby causing an explosion within the cylinders. The explosive forces within the combustion chambers in the cylinders cause linear motion of the pistons within their corresponding cylinders. This linear motion of the pistons is then converted into rotational motion by a crankshaft that, in turn, drives the alternator. As is conventional, the driven alternator generates electrical power.
Engine driven, electrical generators often use an air-cooled engine to drive the generator or alternator. The air-cooled engine can have an engine cooling fan coupled to the crankshaft, that in turn drives cooling air over cylinders of the engine. Engine driven, electrical generators can utilize a coupling means to mount the alternator to the engine and align the crankshaft to the alternator. The alternator is typically driven by the crankshaft while positioned on a downstream side of the engine from the engine cooling fan. Unfortunately, in this arrangement, hot air expelled from cooling the engine can be blown over the generator or alternator causing operation at higher and less efficient temperatures.
Therefore, it would be desirable to provide an electrical generator that provides for positioning of the alternator at a location other than the downstream side of the engine from the engine cooling fan, with an alternator adapter being provided that allows for such positioning of the alternator relative to the engine and engine fan. It would be further desirable for the alternator adapter to mount the alternator to the engine and align the crankshaft to the alternator at a location upstream from the engine cooling fan, while also facilitating airflow through the adapter to the engine cooling fan in a direction opposite the alternator.
Embodiments of the invention are directed to an alternator adaptor for an air-cooled engine that facilitates cooling airflow through the adaptor and to the engine.
In accordance with one aspect of the invention, an alternator adapter for a generator engine includes a main body defining an airflow chamber. The main body includes an airflow outlet in a first end of the main body, an engine shaft opening in a second end of the main body opposite the first end, and an airflow inlet between the first end and the second end. The alternator adaptor also includes an engine mount coupled to the first end of the main body around the airflow outlet and aligned with the engine shaft opening, and an alternator mount coupled to the second end of the main body around the engine shaft opening.
In accordance with another aspect of the invention, an engine-generator set includes a coupling for a generator having an engine mount comprising an airflow opening, a generator mount, and a spacer section holding the engine mount aligned with the generator mount in a spaced relationship allowing airflow into the coupling and to the airflow opening. The engine-generator set also includes an air-cooled engine coupled to the engine mount with a crankshaft extending through the airflow opening and an engine fan coupled to the crankshaft on a side of the air-cooled engine facing the coupling. The engine-generator set further includes a generator coupled to the generator mount and driven by the crankshaft.
In accordance with yet another aspect of the invention, an alternator adapter for an air-cooled engine includes an engine mount having a cooling air opening formed therein, a generator mount, and a frame having an outer casing holding the engine mount aligned with the generator mount. The outer casing includes an airflow inlet fluidically connected to the cooling air opening to allow flow of engine cooling air through the adapter.
Various other features and advantages will be made apparent from the following detailed description and the drawings.
The drawings illustrate preferred embodiments presently contemplated for carrying out the invention.
In the drawings:
The operating environment of the invention is described with respect to a standby generator. However, those skilled in the art will appreciate that the invention is equally applicable for use with portable or other electrical generators. While the invention will be described with respect to an engine-generator set having an airflow arrangement in a generator enclosure, embodiments of the invention are equally applicable for use with engine-generator sets that are not housed in a generator enclosure.
Referring to
The standby generator 30 may include a standby generator enclosure or housing 32 to house the engine-generator set and other associated components. In the embodiment of
The enclosure 32 may also include one or more hoods to cover the standby generator 30. The embodiment shown in
The first hood 52 and the second hood 54 may open outwards beyond the respective first sidewall 40 and second sidewall 42 to expose a top and front entrance into the enclosure 32. The front wall 44 may be relatively short compared to the overall height of the enclosure 32 in part to allow for improved front access into the enclosure 32 when the hoods 52, 54 are open. The back wall 46 may be relatively tall compared to the front wall 44 with the first sidewall 40 and the second sidewall 42 having a forward sloping top edge 48, 50 from the back wall 46 to the front wall 44. The first hood 52 and the second hood 54 can then open upward and slightly forward as they rotate along the forward sloping top edge 48, 50 of each respective sidewall 40, 42. In other embodiments, the first hood 52 and the second hood 54 may rotate about a horizontal or vertical edge of a respective first sidewall 40 and second sidewall 42 between opened and closed positions.
As shown in
Referring now to
The support arm 98 preferably has a channel or gutter 112 extending the length of the support arm to channel water off the front and back of the enclosure 32. The gutter 112 may be formed by raised outer edges that include a first rain seal 114 and a second rain seal 116 on opposite sides of the support arm 98. The first rain seal 114 and the second rain seal 116 each support and seal a respective hood 52, 54 in the closed position. The first rain seal 114 and the second rain seal 116 may also extend across portions of the back wall 46, front wall 44, and respective first and second sidewalls 40, 42 to seal around each perimeter entrance covered by the hoods 52, 54. The rain seals 114, 116 prevent rain from entering the enclosure 32 and may make the enclosure rain tight. Although some water may enter the enclosure 32 without negatively affecting the generator 30, it is desirable to prevent water from entering the electrical areas within the enclosure 32. The rain seals 114, 116 may make the electrical areas within the enclosure 32 rain tight.
According to an exemplary embodiment of the invention, the standby generator 30 has an enclosure 32 with multiple chambers to separate components and one or more airflow inlets in a backwall of the generator enclosure 32, so as to manage heat transfer in the enclosure 32. The multi-chamber generator enclosure 32 may include at least a first chamber 118 and a second chamber 120 each comprising an air inlet 122, 124 and an air outlet 126, 128. The air inlet 122 of the first chamber 118 and the air inlet 124 of the second chamber 120 are shown as airflow openings 80 in the back wall 46 of the multi-chamber generator enclosure 32. The air outlet 126 of the first chamber 118 and the air outlet 128 of the second chamber 120 are shown as airflow openings 80 in opposite end walls 40, 42 of the multi-chamber generator enclosure 32 between the front wall 44 and the back wall 46. Rear transition panels 90, 92, 106 may extend over the air inlets 122, 124 to direct rain off the enclosure away from the inlets.
Referring now to
To support the engine cooling fan 140 on the engine 134, fan base 142 may be mounted on crankshaft 170 of the engine. The fan base 142 may include a domed shape component 172. The fan base 142 may also include a circular plate 174 mounted to the domed shape component 172 to receive the engine cooling fan 140 mounted thereon with a plurality of fasteners 176 that extend through openings 178 in the circular plate 174. A ring gear 180 can also couple to an outer radius of the circular plate 174, the ring gear 180 having gear teeth driven by a starter motor 182 coupled to the crankcase 184. The engine cooling fan 140 may include an annular disc 186 with a plurality of fan blades 188 extending from one side of the annular disc. The fan blades 188 are shown extending from a center opening 190 to a perimeter of the annular disc 186. The annular disc 186 may include openings for the fasteners 176 to mount the engine cooling fan 140 to the fan base 142, which may comprise a plurality of bolts. The crankshaft 170 can be inserted through the center opening 190 in the annular disc 186 such that the fasteners 176 can secure the engine cooling fan 140 to the fan base 142.
The fan cover 138 may include side portions 208 extending around the main section 194 and both arms 196, 198. The side portions 208 extend generally perpendicular to the main section 194 and the arms 196, 198, with rounded corners connecting the side portions 208 to the main section 194 and the arms 196, 198. The side portions 208 may also have a first and a second cutout 210, 212 that fit over the intake pipes 156, 158, and a third cutout 214 that fits over the starter motor 182. The fan cover 138 may include an alternator adapter mounting surface 216 that mates to the alternator adapter 136, with an adapter support plate 218 preferably mounted to the alternator adapter mounting surface 216 around the airflow opening 192. Fasteners 220 can extend through openings in the alternator adapter mounting surface 216 and the adapter support plate 218 to mount the alternator adapter 136 to a fan back plate 221 coupled to the crankcase 184. The adapter support plate 218 is shown having three openings 222 for the fasteners 220 with one opening located in a tab 224 extending outward beyond the fan cover 138. The back plate 221 may have mounting locations 226 each comprising a boss extending forward from the engine 134 and each having a threaded opening to receive a respective fastener 220 from the alternator adapter 136.
The alternator 132 may include a cylindrical outer casing 246 with a first end 248 having an alternator shaft 242 and a second end 250 having alternator cooling fan 252. The cylindrical outer casing 246 may include a rotor bearing carrier 254 adjacent the alternator cooling fan 252 at the second end 250. The rotor bearing carrier 254 may include a first set of projections 256 with openings to receive fasteners 258 mounting a fan guard 260 over the alternator cooling fan 252. The alternator cooling fan 252 can draw a stream of air axially through the alternator 132 to vents 262 in the fan guard 260 covering the fan. The vents 262 may comprise slots around a circumference of the fan guard 260. The rotor bearing carrier 254 may include a second set of projections 264 with openings to receive fasteners 266 mounting the alternator 132 to the alternator adapter 136. The rotor bearing carrier 254 may include a lower support 268, which may include a bottom portion 270 that rests on a vibration isolator 272. The lower support 268 may also include a hollow portion 274 above the bottom portion 270 to access a fastener 276 extending through the bottom portion 270 and the vibration isolator 272.
Referring now to
The engine cooling fan 140 preferably drives the stream of air over cylinders 144, 146 of the engine 134 in a direction toward the first end 34 of the enclosure 32. Each cylinder 144, 146 may comprise one or more air guides 286, 288 mounted over the plurality of cooling fins 204, 206. The cylinders 144, 146 may have inner surfaces 290 generally facing each other and outer surfaces 292 opposite the inner surfaces 290 with an inner air guide 288 mounted over each inner surface 290 and an outer air guide 286 mounted over each outer surface 292. The outer and inner air guide 286, 288 may each have a front portion 294 extending to a front side of the respective cylinders 144, 146 (engine fan side) and a back portion 296 extending to the back side of the respective cylinders 144, 146. The outer and inner air guides 286, 288 direct cooling air from a front side of the cylinders 144, 146 through the cooling fins 204, 206 to the back side of the cylinders 144, 146.
Accordingly, the engine cooling fan 140 may be driven by the engine 134 to force a first stream of cooling air 298 from the engine air duct 244 through the engine 134 in a direction opposite the alternator 132. The outer air guides 286 and the inner air guides 288 mount to the cylinders 144, 146 directing cooling air from the engine cooling fan 140 through the plurality of cooling fins 204, 206. Upon cooling the cylinders 144, 146, the cooling air can flow over an exhaust system 300 operatively coupled to the engine 134. The exhaust system 300 may comprise an exhaust pipe 302, 304 extending from each cylinder 144, 146 to a muffler 306 positioned in a muffler box 308. The muffler box 308 receives cooling air expelled from the engine 134 through an opening 310 into the muffler box 308 and cools the muffler 306 by directing the cooling air over the muffler 306. The muffler box 308 may also direct the cooling air out of the enclosure 32 through vents 312 in the first sidewall 40.
In one embodiment of the invention, an inlet air duct 316 formed in a side of the alternator 132 around the inlet 314 directs airflow into the alternator. The inlet air duct 316 may couple the alternator 132 to a generator control box 317 to provide cooling air flowing through the control box to the alternator. The control box 317 is shown coupled to an airflow opening 124 in the back wall 46 in fluid communication with the inlet air duct 316 coupled to the alternator 132. The inlet air duct 316 and the control box 317 may together form an alternator air duct 319 that couples the alternator 132 to an airflow opening 124 in the back wall 46 in fluid communication with the alternator cooling fan 252. The alternator cooling fan 252 may be driven by the alternator 132 to force a second stream of cooling air 318 from the alternator air duct 319 through the alternator 132 in a direction opposite the engine 134. The alternator cooling fan 252 draws cooling air axially through the alternator 132 from the alternator air duct 319 and can drive the cooling air out of the enclosure 32 through vents 322 in the second sidewall 42. In an alternative embodiment, the inlet air duct 316 optionally extends directly from the alternator 132 to an airflow opening in the back wall 46 and includes a boot (e.g. a rubber seal) coupling the air duct 316 to the airflow opening.
Accordingly, the standby generator 30 may include an engine air duct 244 and an alternator air duct 319 each coupled to at least one of the airflow openings 80, with the engine air duct 244 coupled to the engine 134 to provide a cooling air flow path from the respective airflow opening 80 to the engine cooling fan 140, and with the alternator air duct 319 coupled to the alternator 132 to provide a separate cooling air flow path from the respective airflow opening 80 to the alternator cooling fan 252. Each of the airflow openings 80 coupled to the engine air duct 244 and the alternator air duct 319 may be formed in a same enclosure wall 40, 42, 46, 44 of the generator enclosure 32.
Referring now to
As shown in
The muffler box 308 can surround the muffler 306 managing heat transfer from the muffler 306 within the enclosure 32. The muffler box 308 may include a plurality of heat shield panels 328, 330, 332, 334, 336. For instance, the muffler box 308 may include a top panel 328, a lower forward panel 330, an upper forward panel 332, a rearward panel 334, and two opposing side panels 336 between the forward and rearward panels 330, 332, 334. The lower forward panel 330 extends short of the top panel 328 creating the opening 310 into the muffler box 308. The exhaust pipes 302 (
The upper forward panel 332 extends from the lower forward panel 330 into a region between the exhaust pipes 302 (
Referring now to
According to one embodiment of the invention, the spacer section 228 comprises an outer enclosure 340 (i.e., outer casing) surrounding the crankshaft 170 extending from the engine mount 238 to the generator mount 240. The inlet air duct 244 extends outward from the outer enclosure 340 and in fluid communication with the airflow opening 230 in the engine mount 238. The inlet air duct 244 may extend from the outer enclosure 340 perpendicular to the crankshaft 170, and the inlet air duct 244 preferably extends to airflow opening 122 (
The alternator adapter 136 may have an engine mounting flange 342 and an alternator mounting flange 344 mounted as part of the respective engine mount 238 and generator mount 240. The engine mounting flange 342 may comprise an outlet casement 346 extending from an interior of the main body or spacer section 228 to mate against the alternator adapter mounting surface 216 of the fan cover 138. The outlet casement 346 may surround the airflow opening 230 such that the engine cooling fan 140 cools the engine 134 by drawing air through the outlet casement 346 in the engine mounting flange 342. The alternator mounting flange 344 may surround a chamber wall 348 of the alternator adapter 136 having the engine shaft opening 234 formed therein, the chamber wall 348 blocking airflow through the alternator mount 240. That is, the engine shaft opening 234 may be small to prevent substantial airflow through the alternator mount 240, thus preventing the alternator 132 and engine 134 from drawing air in opposite directions in the alternator adapter 136. The chamber wall 348 may comprise an indented circular ridge 350 around a perimeter edge to receive the cylindrical outer casing 246 of the alternator 132.
The engine 134 may include a bushing 362 coupled around the crankshaft 170. The bushing 362 may have an “L” shaped cross-section that encircles the crankshaft 170 forming a cylindrical component 364 and a flat component 366. The fan base 142 couples to the bushing 362 mounted to the crankshaft 170 with a cylindrical component 368 of the fan base 142 surrounding the cylindrical component 364 of the bushing 362, and a flat component 370 of the fan base 142 fastened to the flat component 366 of the bushing 362. The domed shape component 172 of the fan base 142 extends over the flat component 366 of the bushing 362 allowing the engine cooling fan 140 to be mounted proximate the crankcase 184.
Referring now to
In an exemplary embodiment, the main body 228 may comprise a cylindrical outer casing 378 holding the engine mount 238 and the alternator mount 240 at opposite ends of the cylindrical outer casing 378, the engine mount 238 aligned with the engine shaft opening 234 of the generator mount 240. The airflow inlet 376 may be formed in the cylindrical outer casing 378 at a location between the first end 232 and the second end 236, and the airflow inlet 376 may be perpendicular to the airflow outlet 230. The cylindrical outer casing 378 may comprise an oblong cylindrical outer casing 380 with the alternator mount 240 at one end of the oblong cylindrical outer casing 380 having a circular outer ridge 350 to receive the alternator 132 (
To mount the alternator adapter 136, a plurality of engine mounting projections 386 may extend outward from the engine mount 238, and a plurality of alternator mounting projections 388 may extend outward from the alternator mount 240. The plurality of engine mounting projections 386 may include openings that receive fasteners 220 (
The frame 374 may comprise the cylinder 378 having the inlet air duct 244 extending outward from a side of the cylinder. That is, the inlet air duct 244 couples to the airflow inlet 376 and may extend outward from the outer casing 340/cylindrical outer casing 378 of the main body 228. The inlet air duct 244 can have a generally rectangular cross-section 390 with a width approximately equal to the length of the adapter cylinder 378, and a length slightly larger than a diameter of the adapter cylinder 378. The inlet air duct 244 can extend across a center of the adapter cylinder 378 with a pair of opposing side surfaces 392, 394 curving into the adapter cylinder 378.
Beneficially, embodiments of the invention provide an alternator adapter that mounts upstream from an air-cooled engine such that an engine cooling fan may be positioned between the alternator and the engine. The alternator adapter has a main body with an air inlet and an air outlet to provide airflow through the adapter to the engine cooling fan. An engine mount can surround the air outlet and an alternator mount can surround an engine shaft opening preferably aligned with the air outlet. The engine cooling fan may be coupled to a crankshaft of the engine extending through the airflow outlet to draw a stream of cooling air from the air inlet through the air outlet to the engine. The alternator may have an alternator fan that draws air through the alternator in a direction opposite the engine. Accordingly, the alternator adapter allows the engine cooling fan to face a direction opposite the alternator to provide opposing airflow paths through the engine and the alternator.
Therefore, according to one embodiment of the invention, an alternator adapter for a generator engine includes a main body defining an airflow chamber. The main body includes an airflow outlet in a first end of the main body, an engine shaft opening in a second end of the main body opposite the first end, and an airflow inlet between the first end and the second end. The alternator adaptor also includes an engine mount coupled to the first end of the main body around the airflow outlet and aligned with the engine shaft opening, and an alternator mount coupled to the second end of the main body around the engine shaft opening.
According to another embodiment of the invention, an engine-generator set includes a coupling for a generator having an engine mount comprising an airflow opening, a generator mount, and a spacer section holding the engine mount aligned with the generator mount in a spaced relationship allowing airflow into the coupling and to the airflow opening. The engine-generator set also includes an air-cooled engine coupled to the engine mount with a crankshaft extending through the airflow opening and an engine fan coupled to the crankshaft on a side of the air-cooled engine facing the coupling. The engine-generator set further includes a generator coupled to the generator mount and driven by the crankshaft.
According to yet another embodiment of the invention, an alternator adapter for an air-cooled engine includes an engine mount having a cooling air opening formed therein, a generator mount, and a frame having an outer casing holding the engine mount aligned with the generator mount. The outer casing includes an airflow inlet fluidically connected to the cooling air opening to allow flow of engine cooling air through the adapter.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
The present application is a non-provisional of, and claims priority to, U.S. Provisional Patent Application Ser. No. 62/681,157, filed Jun. 6, 2018, the disclosure of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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62681157 | Jun 2018 | US |