WO2019159198A1

WO2019159198A1 - Flywheel for magneto generator systems

Info

Publication number: WO2019159198A1
Application number: PCT/IN2019/050121
Authority: WO
Inventors: Umashankar Raman; Ravikumar Sivasubramanian; Kannayiram PERUMAL GOUNDER
Original assignee: India Nippon Electricals Ltd
Priority date: 2018-02-16
Filing date: 2019-02-15
Publication date: 2019-08-22

Abstract

A flywheel for a magneto generator system comprises a flywheel cup having a base, a mouth away from the base, and a protrusion extending from the base towards the mouth. The protrusion has a taper to receive a counter-taper of a crankshaft of an engine. The flywheel further comprises a ring mountable on the protrusion. The present subject matter eliminates the use of a boss for mounting a flywheel on a crankshaft. Therefore, the present subject matter reduces the weight of the flywheel and simplifies the design of the flywheel.

Description

FLYWHEEL FOR MAGNETO GENERATOR SYSTEMS

TECHNICAL FIELD

[0001] The present subject matter relates to flywheel for a magneto generator system in general and, in particular, to a flywheel magneto generator for an internal combustion engine.

BACKGROUND

[0002] A magneto generator system having a flywheel, also referred to as a flywheel magneto generator, may be used in an internal combustion engine for producing electrical energy from stored rotational kinetic energy of the internal combustion engine. Typically, the flywheel magneto generator comprises a flywheel, a plurality of permanent magnets, a plurality of radially outwardly extending pole cores, and one or more connected windings. The permanent magnets may be arranged within the flywheel. The connected windings may be wound on the pole cores.

[0003] Generally, the flywheel comprises a flywheel cup. Further, a boss is fixed to the flywheel cup using a plurality of rivets to mount the flywheel cup on the crankshaft.

BRIEF DESCRIPTION OF DRAWINGS

[0004] The features, aspects, and advantages of the present subject matter will be better understood with regard to the following description, and accompanying figures. The use of the same reference number in different figures indicates similar or identical features and components.

[0005] Fig. 1 illustrates a perspective view of flywheel, in accordance with an implementation of the present subject matter.

[0006] Fig. 2 illustrates a cross-sectional view of a flywheel assembly, in accordance with an implementation of the present subject matter. [0007] Fig. 3 illustrates a cross-sectional view of the flywheel assembly, in accordance with an implementation of the present subject matter.

[0008]

DETAILED DESCRIPTION

[0009] A flywheel may be used in vehicles, such as two-wheelers, for storing energy from an internal combustion engine (also referred to as engine) of the vehicle. In the vehicle, the flywheel is connected to crankshaft of the engine. Typically, the flywheel comprises a flywheel cup. A boss is coupled to the flywheel cup using a plurality of rivets and is coupled to the crankshaft to mount the flywheel cup on the crankshaft. The use of boss rivets makes the flywheel bulky and more expensive.

[0010] In accordance with an implementation of the present subject matter, a flywheel for a magneto generator is provided. The flywheel comprises a flywheel cup having a base, a mouth away from the base, and a protrusion extending from the base towards the mouth. The protrusion has a taper to receive a counter-taper of a crankshaft of an engine, such as an engine of a vehicle. The flywheel further comprises a ring mountable on the protrusion to control the taper of the protrusion.

[0011] By providing a protrusion in the flywheel cup, the present subject matter eliminates the use of boss and rivets to mount the flywheel on the crankshaft. Therefore, the present subject matter reduces the weight of the flywheel and simplifies the design of the flywheel. Further, the assembly of the flywheel is simplified.

[0012] Fig. 1 illustrates a perspective view of a flywheel 100 for a magneto generator, in accordance with an implementation of the present subject matter.

[0013] The magneto generator system may be used in an internal combustion engine, also referred to as engine, of a vehicle, such as a two-wheeler. The magneto generator system may be used for producing electrical energy from mechanical energy of the engine. [0014] The magneto generator system comprises the flywheel 100, which is also referred to as the flywheel rotor 100. In addition to the flywheel rotor 100, the magneto generator system may also include a plurality of permanent magnets, a plurality of pole cores, and one or more connected windings, which are not shown in Fig. 1. The permanent magnets may be arranged on an inner surface of the flywheel 100. Each pole core may face a permanent magnet. Further, the connected windings are wound on the pole cores.

[0001] The magneto generator system may produce electrical energy due to rotation of the flywheel rotor 100 in the presence of stator coils. As illustrated in Fig. 1, the flywheel 100 includes a flywheel cup 102. The flywheel cup 102 may be made of a sheet metal. The flywheel cup 102 may be bowl- shaped, and may be mounted on one end of a crankshaft (not shown in Fig. 1 ) of the engine.

[0002] The flywheel cup 102 has a base 104, which may be circular in shape, and a rim 106. The rim 106 surrounds the base 104 and extends from the circumference of the base 104. Further, the rim 106 is perpendicular to the circular base 104. A side of the rim 106 that is opposite the side attached to the base 104 may be open, thereby forming a mouth 108. Accordingly, the mouth 108 can be said to be away from the base 104. The flywheel cup 102 further comprises a protrusion 110 which extends from the base 104 towards the mouth 108. A ring 112 is mountable on the protrusion 110, as will be explained with reference to Fig. 2.

[0003] Fig. 2 illustrates a cross-sectional view of the flywheel 100, in accordance with an implementation of the present subject matter. As can be seen, the protrusion 110 extends from the base 104 towards the mouth 108 around a central axis 201 of the base 104. The protrusion 110 may have a taper. The taper may be a forward taper or a reverse taper.

[0004] A forward taper 202 of the protrusion 110 is illustrated in Fig. 2. In the case of the forward taper 202, a diameter 206 at a beginning of the protrusion 110 on the base 104 is lesser than a diameter 204 of the protrusion 110 at the end of the protrusion 110, which is nearer to the mouth 108 compared to the beginning of the protrusion 110. The diameter 204 may be referred to as a major diameter and the diameter 206 may be referred to as a minor diameter.

[0005] The forward taper 202 corresponds to a counter-taper 208 of the crankshaft 210. The counter- taper 208 of the crankshaft 210 is to be secured in the forward taper 202 of the flywheel cup 102 for holding the flywheel 100 on the crankshaft 210.

[0006] When a tightening torque is applied to the flywheel 100, the flywheel

100 may move towards the crankshaft 210. For instance, the flywheel 100 may move along the crankshaft 210 in a left-hand side direction on a plane illustrated in Fig. 2. Such a movement may damage the forward taper 202. For example, the diameter 204 may increase. This displacement of the flywheel relative to the crankshaft 210 is referred to as a sink. The sink is to be controlled to prevent any damage to the flywheel 100.

[0001] In accordance with an implementation of the present subject matter, to control the sink in the forward taper 202, a ring 112 is mounted on the protrusion 110. The ring 112 supports the flywheel cup 102 on the crankshaft 210. The ring 112 also enables the control of the sink by limiting the displacement of the flywheel 100 on the crankshaft 210 to less than a certain specified value. The ring 112 can be fixed on the protrusion 110 by means of shrink fit or press fit based on requirements.

[0002] The present subject matter eliminates the use of boss for coupling a one-way clutch with the flywheel cup 102, as will be explained below.

[0003] Fig. 3 illustrates a cross-sectional view of the flywheel 100 showing a one-way clutch 302 coupled to the flywheel cup 102, in accordance with an implementation of the present subject matter. For coupling the one-way clutch 302 with the flywheel cup 102, a holder 304 is provided on the base 104 of the flywheel cup 102. The holder 304 may extend as an outward protrusion from the base 104 in a direction opposite to a direction in which the protrusion 110 extends. The holder 304 may be ring-shaped. The one-way clutch 302 along with the flywheel 100 may be referred to as a flywheel assembly 306.

[0004] Fig. 3 further illustrates a reverse taper 310 of the protrusion 110. In the reverse taper 310, the diameter 204 at the beginning of the protrusion 110 on the base 106 is greater than the diameter 206 of the protrusion 110 at the end of the protrusion 110. Though Fig. 3 illustrates the flywheel assembly with the reverse taper 310 of the protrusion 110, it is also possible for the one-way clutch 302 to be disposed on the flywheel cup 102 having the protrusion 110 with a forward taper 202. Further, Fig. 3 shows a puller thread 308 which may be provided on the periphery of the protrusion 110 for removing the flywheel 100 from the crankshaft 210 during servicing.

[0005] Thus, according to the present subject matter, the flywheel obviates the need for the boss and rivets for attaching the flywheel cup to a crankshaft. Further, the present subject matter provides a flywheel that is simple to manufacture and assemble and reduces overall part and process cost.

[0006] Although the present subject matter has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the subject matter, will become apparent to persons skilled in the art upon reference to the description of the subject matter and are intended to be covered herein.

Claims

We claim:

1. A flywheel for a magneto generator system, the flywheel comprising:

a flywheel cup having:

a base;

a mouth away from the base; and

a protrusion extending from the base towards the mouth, wherein the protrusion has a taper to receive a counter-taper of a crankshaft of an engine; and

a ring mountable on the protrusion.

2. The flywheel as claimed in claim 1 , wherein the taper is one of a forward taper and a reverse taper.

3. The flywheel as claimed in claim 1, comprising a holder provided on the base, and wherein the holder is to receive a one-way clutch.

4. A flywheel assembly comprising:

a flywheel comprising:

a flywheel cup having:

a base;

a mouth away from the base;

a protrusion extending from the base towards the mouth, wherein the protrusion has a taper to receive a counter-taper of a crankshaft of an engine;

a holder provided on the base; and

a ring mountable on the protrusion; and

a one-way clutch coupled to the flywheel cup through the holder.

5. The flywheel assembly as claimed in claim 4, wherein the holder extends as an outward protrusion from the base in a direction opposite a direction in which the protrusion extends.

6. A magneto generator system comprising:

the flywheel as claimed in any one of claims 1-4;

a plurality of permanent magnets arranged on an inner surface of the flywheel;

a plurality of pole cores, each pole core facing a permanent magnet; and one or more connected windings wound on a pole core of the plurality of pole cores.