Claims:I claim:
1. A supercharger (10) for a single cylinder engine, said supercharger (10) comprising at least,
- a housing (12), a central shaft (14) located in said housing (12) extending the length of said housing (12), at least one rotor blade (16) mounted on the central shaft (14) and a gear (18) mounted said central shaft (14);
characterized in that
at least one single sided bearing (20) provided in said housing (12), adapted to support said central shaft (14); and
a first end plate (22) to support rotor blades (16) at the other end of the housing (12) beyond the rotor blades (16).
2. The supercharger (10) as claimed in claim 1, wherein said housing (12) comprising at least one cavity (24) adapted to store a lubricant.
3. The supercharger (10) as claimed in claim 1 and 2, wherein said housing (12) comprises at least one bore (26) extending from said cavity (24) at one end of said bore (26) to said at least one bearing (20) at the other end of said bore (26).
4. The supercharge (10) as claimed in claim 1, wherein said at least one bearing (20) is such that the length of the bearing (20) is such that the load from the driven pulley of the supercharger (10) is exerted on one side of the at least one bearing (20).
5. The supercharger (10) as claimed in claim 1, wherein said end plate (22) is located beyond the rotor blades (16) in a manner such that the clearance between said end plate (22) and said rotor blades (16) is minimal.
6. The supercharger (10) as claimed in claim 1, wherein said supercharger (10) comprises a bypass channel (30) and a bypass valve (32) located in said bypass channel (30).
7. The supercharger (10) as claimed in claim 1 and 6, wherein said at least one single sided bearing (20) allow a simple design of the bypass valve (32).
, Description:Field of the invention
[0001] This disclosure relates to a supercharger for a single cylinder engine.
Background of the invention:
[0002] A supercharger is a device that is well known in the state of the art. Superchargers are driven by the engines to which the supercharger supplies the air. The supercharger has a driven pulley which is connected to the central shaft of the supercharger. The driven pulley is connected to a pulley on the engine through a belt drive. Rotor blades are mounted on the central shaft. The central shaft is supported by bearings and lubricated by oil. The superchargers are provided with at least two bearings, one bearing is provided at the end which is in proximity of the driven pulley while the other bearing is provided beyond the rotor blades. Both the bearings need to be lubricated, for lubricating the bearing which is in proximity of the driven pulley there bores are provided from a cavity near the bearing. For lubricating the bearing which is beyond the rotor blades, additional bores need to be made and a flow connection between an oil sources and the bores need to be provided. Also the bypass valve can be provided only after the bearing which is beyond the rotor blades.
Brief description of the accompanying drawings:
[0003] An embodiment of the disclosure is described with reference to the following accompanying drawings;
[0004] Figure 1 and Figure 2 illustrates a supercharger in accordance with this disclosure.
Detailed description of the embodiments:
Figure 1 and Figure 2 illustrates a supercharger in accordance with this disclosure. The supercharger 10 for a single cylinder engine , the supercharger comprises a housing 12, a central shaft 14 located in the housing 12 extending the length of the housing 12, at least one rotor blade 16 mounted on the central shaft 14 and a gear 18 mounted on the central shaft 14. The supercharger is characterized such that at least one single sided bearing 20 is provided in the housing 12, adapted to support the central shaft 14 and a first end plate 22 to support the rotor blades 16 at the other end of the housing 12 beyond the rotor blades 16.
[0005] The construction details of the supercharger 10 in accordance with this disclosure can be explained as follows. The housing 12 is provided with an axial bore through which the central shaft 14 extends the length of the housing 12. The rotor blades 16 are mounted on the central shaft or the central shaft 14 with the rotor blades 16 can be one single component. A driven pulley is fitted to one end of the shaft and is external to the housing 12. There is also provided within the housing a gear assembly with two gear wheels, one of the two gear wheels is directly mounted on the central shaft 14 and the second gear wheel is driven by the first gear wheel. The central shaft 14 is supported by at least one bearing 20. The at least one bearing 20 is said to be a single sided bearing because the bearing 20 is provided only one side of the rotor blades 16. The supercharger 10 further comprises a second end plate 28 which is fitted to the end of the housing 12 which is in proximity of the driven pulley of the supercharger 10. The housing 12 comprises at least one recess which forms at least one cavity 24 when the second end plate 28 is fitted to the housing. The at least one cavity 24 is adapted to store lubricant. The lubricant is used to lubricate the bearing 20 and the gear wheels of the gear assembly. The housing 12 comprises at least one bore 26 extending from the at least one cavity 24 at one end of the bore 26 to the at least one bearing 20 at the other end of the bore 26. The cavity 24 allows to store onetime oil filing.
[0006] The least one bearing 20 is such that the length of the bearing 20 is such that the load from the driven pulley of the supercharger 10 is exerted on one side of the at least one bearing 20. Since the supercharger 10 of this disclosure is used in single cylinder engines the bearing can be designed as shaft bearing without the necessity of having any ball bearing. The bearing 20 length is kept high such that the bearing 20 acts as two bearing in a manner such that the load from the driven pulley come on one side of the bearing 20 and the load from pressurizing the air through the rotor blades comes from the other side. This also ensures that the central shaft bending if any is under control, which in turns ensure performance parameters of the supercharger 10.
[0007] The first end plate 22 which is located beyond the rotor blades 16 is a simple end plate which is fitted in manner such that the clearance between the end plate 22 and the rotor blades 16 is minimal. When the second end plate 28 is fitted to the housing to form the cavity 24, a first sealing ring is provided to ensure that there is not oil leakage to the outside. A second sealing ring which is located towards the rotor blades side ensures that there is no oil leakage from the bearing 20 to the air side where the rotor blades 16 are conveying the air.
[0008] The supercharger 10 further comprises a bypass channel 30 as seen in figure 2. The at least one single sided bearing 20 allow a simple design of the bypass valve 32. A flap 32 is provided in the bypass channel 32 can be actuated in a manner such that air flow through the channel bypassing the rotor blades 16 and directly enters the engine. The actuation of the flap 32 can be controlled through the accelerator pedal or handle controlled which allows the flexibility of the engine being provided pressurized air only when it is required. This is particularly important for single cylinder naturally aspirates engine operating in full load condition where lambda gets critical.
[0009] Thus the supercharger 10 as disclosed herein above required only one set of lubrication bores which lubricate the single sided bearing 20. Thus additional bores are not necessary since a second bearing is not present. Further the length of the single sided bearing 20 avoids the need of any ball bearing to support the central shaft. Since only one single sided bearing 20 is used in the supercharger 10 it is possible to design the supercharger with radial inlet and radial outlet. The radial inlet and radial outlet helps reducing the packaging of the supercharger 10. The minimal clearance between the first end plate 22 and the rotor blades 16 increases the efficiency of the supercharger. The single sided bearing also ensures that the bypass valve can be simple design and can occupy less space as there is no second bearing.
[00010] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.