GB1592618A - Generator casing and a coupling between the generator and the driving motor - Google Patents

Description

(54) GENERATOR CASING AND A COUPLING BETWEEN THE GENERATOR AND THE DRIVING MOTOR (71) We, ZAKLADY OKRETOWYCH UR ZADZEN ELEKTRYCZNYCH "ELMOR" Gdansk, ul. Walowa 63, Poland, a State Enterprise organised and existing under the laws of the State of Poland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following state menu: This invention relates to a generator casing and a coupling between the generator and the driving motor. In particular the invention relates to a brushless generator wherein a rotor is provided with one support bearing and where the generator is mounted on the casing of the driving motor.

Known brushless generators have an inner stator assembly or pack placed on a uniform sleeve with a front disc constituting a part of a casing for the generator. A support disc for the rotor is sometimes mounted on a flange of a driving shaft. Usually the generator casing is attached by means of a flange to the casing of the driving motor.

The designs hitherto known and used have several disadvantages and inconveniences in their operation. Winding and impregnating operations of the inner stator pack is difficult.

A generator shaft, mounted on the support disc by means of a flange having small diameter and thickness, does not provide appropriate alignment with the driving shaft.

The air flow for cooling the interior of the generator is distributed unequally and results in local overheating of assemblies. This invention aims at obviating or mitigating the disadvantages and inconveniences of hitherto known designs.

According to the present invention there is provided a generator casing and a coupling between the generator and the driving motor comprising a sleeve forming part of an inner stator assembly and removably coupled to a front disc of the casing, said sleeve having a bearing housing in its front portion, a rotor support disc mounted on a flange of a generator shaft, said generator shaft flange being coupled axially to a flange in a shaft of the driving motor, said generator shaft being situated within said bearing housing and said sleeve being disposed outside said generator shaft.

Numerous tests and observations have resulted in unexpectedly successful achievement by using a sleeve forming part of an inner stator assembly which is removably coupled to a front disc of the housing.

A flange of the driving motor shaft is mounted axially onto a larger and thicker flange of generator shaft, whereon a supporting disc of a rotor has been fixedly mounted.

Rotating members of the rotor, have a cylindrical baffle and the sleeve of the inner stator assembly is provided with ribs, in order to obtain the most convenient flow of cooling air.

The construction of the generator casing, according to the invention, results in improved facility of maintenance and repairs of rotor members without need of dismantling.

This is possible as the supporting disc of the rotor has openings therein covered by removable covers and when the covers are removed access behind the disc is permitted.

The new mounting arrangement of the supporting disc provides a greater rigidity of the casing and facilitates mounting the rotor on the manufactured end of the driving motor shaft.

In order to stiffen a generating set, the casing has lugs for mounting the generator, which reduce transverse displacements.

An embodiment of the present invention will now be described by way of example, with reference to the accompanying drawings wherein: Fig. I is a longitudinal sectional view of a generator made in accordance with the present invention; and Fig. 2 is a front view of the generator of Fig. 1.

Referring to the drawings, a stationary sleeve 1 forming part of the inner stator assembly is disposed outside a generator shaft 5 of a generator, said generator shaft having a radial clearance 13, and the sleeve I having in a front portion a bearing housing 12 for the shaft 5. On this end of the sleeve 1, a hub of a front disc 2 is force fitted and is secured additionally by a set screw 18.

A rotor 4 is mounted on a support disc 3 and fixed by screws 17. The support disc 3 is secured by screws 19 to a flange of the generator shaft 5 coaxially coupled to a shaft 6 of a driving motor (not shown). The flanges of the shafts 5 and 6 are held together by screws 20. The front disc 2 has on its surface access openings 8 each provided with a cover 9 directing the flow of cooling air from the exterior of the machine via the casing louvres towards ports 7 during operation of the generator. The access openings 8 permit access to behind the disc 2, when the generator is not in use. A cylindrical baffle 14 on the interior of the front disc 2 distributes the air towards holes 16 and 11. The air from holes 11 directed by guide vanes 10 in the form of ribs provides cooling of the generator. On the support disc 3 of the rotor there is mounted a toothed starting ring 15.

The invention is used in generators designed for engine driven generator sets. In case of larger overall dimensions of a generator there can be fitted special bosses (not shown) under the lugs 21 of the casing in order to reduce transverse displacements and to stiffen the generator set protecting it from vibrations during operation, when mounted on a driving motor.

WHAT WE CLAIM IS: 1. A generator casing and a coupling between the generator and the driving motor comprising a sleeve forming part of an inner stator assembly and removably coupled to a front disc of the casing, said sleeve having a bearing housing in its front portion, a rotor support disc mounted on a flange of a generator shaft, said generator shaft flange being coupled axially to a flange on a shaft of the driving motor said generator shaft being situated within said bearing housing and said sleeve being disposed outside said generator shaft.

2. A casing as claimed in claim 1, wherein the front disc has ports located therein for permitting the passage of cooling air therethrough, and an access opening closed by a cover during operation of the generator.

3. A casing as claimed in either claim 1 or 2, wherein the sleeve of the inner stator assembly and the generator shaft have a radial clearance, and guide vanes for air flow in the form of ribs are provided between ventilating holes on the internal surface of the sleeve.

4. A casing as claimed in any preceding claim wherein the front disc has a cylindrical baffle.

5. A casing as claimed in any preceding claim, including a toothed starting rim on the support disc of the rotor.

6. A generator casing and generatordriving motor coupling, substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. Fig. 2 is a front view of the generator of Fig. 1. Referring to the drawings, a stationary sleeve 1 forming part of the inner stator assembly is disposed outside a generator shaft 5 of a generator, said generator shaft having a radial clearance 13, and the sleeve I having in a front portion a bearing housing 12 for the shaft 5. On this end of the sleeve 1, a hub of a front disc 2 is force fitted and is secured additionally by a set screw 18. A rotor 4 is mounted on a support disc 3 and fixed by screws 17. The support disc 3 is secured by screws 19 to a flange of the generator shaft 5 coaxially coupled to a shaft 6 of a driving motor (not shown). The flanges of the shafts 5 and 6 are held together by screws 20. The front disc 2 has on its surface access openings 8 each provided with a cover 9 directing the flow of cooling air from the exterior of the machine via the casing louvres towards ports 7 during operation of the generator. The access openings 8 permit access to behind the disc 2, when the generator is not in use. A cylindrical baffle 14 on the interior of the front disc 2 distributes the air towards holes 16 and 11. The air from holes 11 directed by guide vanes 10 in the form of ribs provides cooling of the generator. On the support disc 3 of the rotor there is mounted a toothed starting ring 15. The invention is used in generators designed for engine driven generator sets. In case of larger overall dimensions of a generator there can be fitted special bosses (not shown) under the lugs 21 of the casing in order to reduce transverse displacements and to stiffen the generator set protecting it from vibrations during operation, when mounted on a driving motor. WHAT WE CLAIM IS:

1. A generator casing and a coupling between the generator and the driving motor comprising a sleeve forming part of an inner stator assembly and removably coupled to a front disc of the casing, said sleeve having a bearing housing in its front portion, a rotor support disc mounted on a flange of a generator shaft, said generator shaft flange being coupled axially to a flange on a shaft of the driving motor said generator shaft being situated within said bearing housing and said sleeve being disposed outside said generator shaft.

2. A casing as claimed in claim 1, wherein the front disc has ports located therein for permitting the passage of cooling air therethrough, and an access opening closed by a cover during operation of the generator.

3. A casing as claimed in either claim 1 or 2, wherein the sleeve of the inner stator assembly and the generator shaft have a radial clearance, and guide vanes for air flow in the form of ribs are provided between ventilating holes on the internal surface of the sleeve.

4. A casing as claimed in any preceding claim wherein the front disc has a cylindrical baffle.

5. A casing as claimed in any preceding claim, including a toothed starting rim on the support disc of the rotor.

6. A generator casing and generatordriving motor coupling, substantially as hereinbefore described with reference to the accompanying drawings.