CLIAMS:We claim:
1. A heat dissipating assembly for an internal fan type alternator (10), said internal fan type alternator (10) comprises
a connecting plate (18) with a plurality of bus bars (26) connecting a plurality of leads extending from a stator (16) to a rectifier plate (20) with a set of diodes (29);
a slip ring-end shield (24) enclosing the connecting plate (18) and the rectifier plate (20); characterized in said connecting plate (18)
a plurality of ribs (28) spaced apart with each other at the circumferential edge of said connecting plate (18).
2. The heat dissipating assembly of claim 1, wherein said plurality of ribs (28) have a gap (30) in between them for air-circulation.
3. The heat dissipating assembly of claim 1, wherein the connecting plate (18) is wider than the rectifier plate (20) and said connecting plate (18) is fitted to inner edge of the slip ring- end shield (24) without any clearance.
4. The heat dissipating assembly of claim 1, wherein the connecting plate (18) has a plurality of holes (27) of specific shape surrounding the plurality of bus bars (26).
5. The heat dissipating assembly of claim 1, wherein the rectifier plate (20) is fitted to the connecting plate (18) such that the bus bars (26) are coupled to the corresponding diodes (29).
6. The heat dissipating assembly of claim 1, wherein the gaps (30) formed between the ribs (28) assist in entry of air and circulation of air through the plurality of holes (27) of the connecting plate (18) and the diodes (29) of the rectifier plate (20).
,TagSPECI:The following specification particularly describes the invention and the manner in which it is to be performed.

Field of the invention:
[001] This invention relates to a heat dissipating assembly for an internal fan type alternator with an internal rectifier. More specifically, it relates to an arrangement for cooling a rectifier plate of the internal fan type alternator used in vehicles.

Background of the invention
[002] In an internal fan type alternator, the internal fans draw the ambient air through the end shields (drive end-shield and slip ring-end shield) and pass it through the components of the alternator for dissipating heat. A rectifier plate with diodes and a voltage regulator are provided at the slip ring-end shield of the alternator. In these types of alternators, a heat sink is provided for cooling the rectifier plate. However it does not provide sufficient cooling and also requires additional space, material, and cost. Insufficient cooling of the rectifier plate results in reduction of the output of the alternator.
[003] With an existing rectifier arrangement in an internal fan type alternator, there is also problem due to air turbulence.
[004] DE9212744U1 discloses an alternator having a rectifier plate kept in open condition, without being enclosed. Further, it has an additional baffle plate which is attached using screws to the rectifier.

Brief description of the drawing:
[005] The invention is described with reference to the following drawings:
[006] Fig. 1 shows an exploded perspective view of an internal fan type alternator with a vacuum pump, in accordance with an embodiment of the invention.
[007] Fig. 2 shows a perspective view of a connecting plate of an internal fan type alternator, in accordance with an embodiment of the invention.
[008] Fig. 3 shows an assembly of a connecting plate and a rectifier plate of an internal fan type alternator, in accordance with an embodiment of the invention.
[009] Fig. 4 shows a schematic view explaining air-flow in an internal fan type alternator, in accordance with an embodiment of the invention.
[0010] Fig. 5 shows an assembly of a connecting plate and a rectifier plate with a slip ring-end shield of an internal fan type alternator, in accordance with an embodiment of the invention.

Detailed description of the embodiments of the invention
[0011] Fig. 1 shows an exploded perspective view of an internal fan type alternator with a vacuum pump, in accordance with an embodiment of the invention. The internal fan type alternator 10 comprises a rotor 12, fans 14, a stator 16, a connecting plate 18, and a rectifier plate 20 assembled sequentially between a drive-end shield 22 and a slip ring-end shield 24. Along with these components, other components like a voltage regulator 32 and optionally a vacuum pump 34 are connected to the internal fan type alternator 10.
[0012] Fig. 2 shows a perspective view of a connecting plate of an internal fan type alternator, in accordance with an embodiment of the invention. The connecting plate 18 has a several bus bars 26 which are used for connecting several leads extending from the stator 16, to the rectifier plate 20. Several holes 27 of specific shape are formed in the connecting plate 18 surrounding the bus bars 26.
[0013] In an embodiment of the invention, the holes are of L-shape and are much wider than the bus bars 26.
[0014] Fig. 3 shows an assembly of a connecting plate and a rectifier plate of an internal fan type alternator, in accordance with an embodiment of the invention. The rectifier plate 20 has several diodes 29. The rectifier plate 20 is fitted to the connecting plate 18 such that the bus bars 26 are coupled to the corresponding diodes 29. When assembled, the slip ring-end shield 24 encloses the connecting plate 18 and the rectifier plate 20.
[0015] As shown in Fig.2 and Fig. 3, the connecting plate 18 has several ribs 28 spaced apart with each other at the circumferential edge of the connecting plate 18. A gap 30 is formed between adjacent ribs 28.
[0016] Fig. 4 is a schematic view showing the air-flow in an internal fan type alternator, in accordance with an embodiment of the invention. Fans 14 draw ambient air from both sides, which is circulated inside and finally exit through slots provided in the drive end shield 22 and slip ring-end shield 24.
[0017] The gaps 30 formed between the ribs 28 of the connecting plate 18 assist in entry of air, and circulation of the air through the holes 27 of the connecting plate 18 and over the diodes 29 of the rectifier plate 20. As a result, the diodes 29 and even the voltage regulator 32 are cooled effectively, which improves the performance of the alternator 10.
[0018] Fig. 5 shows an assembly of a connecting plate and a rectifier plate with a slip-ring-end shield of an internal fan type alternator, in accordance with an embodiment of the invention. The connecting plate 18 is wider than the rectifier plate 20. In other words, the diameter of the connecting plate 18 is more than that of the rectifier plate 20. The area/diameter of the connecting plate 18 is selected such that the connecting plate 18 is fitted to inner edge of the slip ring-end shield 24 without any clearance.
[0019] As the connecting plate 18 is fitted without any clearance to the inner edge of the slip ring-end shield 24, air turbulence is prevented. Thereby, damage to the components like diodes 29 and the wirings are avoided.
[0020] Excellent thermal management is achieved without requiring additional components, cost, and space by a simple and effective air-circulation arrangement.
[0021] 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, 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 appended claims.