JPH07123649A - Ac generator with vacuum pump - Google Patents

Abstract

PURPOSE:To avoid the penetration of water, etc., into brushes and slip rings without obstructing the cooling and discharge of abrasion dust by a method wherein bent trenches which communicate with lift pin insertion holes provided in the side wall of a rear frame are provided on a vacuum pump mounting face on the outer side of the rear frame. CONSTITUTION:The shaft 2 of a generator is supported by bearings 11 and 12 which are provided inside a rear frame 1a and a front frame 2a. A pair of slip rings 3 are attached to the shaft on the rear frame 1a side. A pair of brushes 5 are inserted into the brush container of a brush holder 4 and the brushes 5 are biased by springs 6 are slidable an the slip rings 3. A pair of cores 13 are fixed near the center of the shaft 2 and a field coil is wound between the cores 13. A field current is supplied to the field coil through the brushes 5, the slip rings 3 and lead wires 15a and 15b. Further, fins of which a cooling fan 16 is composed are fixed to the side planes of the cores 13 and a stator core 17 to which an output winding is applied is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brush waterproofing structure for removing brush abrasion powder of a brush of an AC generator with a vacuum pump.

[0002]

2. Description of the Related Art Generally, an alternator for a vehicle such as an automobile is used in a bad environment, and therefore, it is necessary to take measures for waterproofing and dustproofing on a portion such as a slip ring portion.

Therefore, in the past, for example, in Japanese Utility Model Publication No. 61-1784.
As disclosed in Japanese Patent No. 9 etc., a waterproof plug is attached to the brush lift pin hole for waterproofing.

In such a vehicle AC generator having a waterproof and dustproof structure, since the brush is enclosed so as to surround it, the slip ring and the brush portion are in a hermetically sealed state and the temperature rises and the brush Abrasive powder was not discharged, causing abnormal wear of the brush.

[0005]

In the above-mentioned prior art, since the hole for inserting the brush lift pin is closed, the waterproof and dustproof effects are excellent, but the slip ring and the brush portion are in a sealed state and the temperature rises extremely. Moreover, since the brush wear powder is not discharged, the brush is abnormally worn.

In view of the above problems, it is an object of the present invention to provide an AC generator with a vacuum pump which can prevent water and the like from entering a brush and a slip ring without hindering cooling and discharging of abrasion powder.

[0007]

Means for Solving the Problems Starting from a lift pin insertion hole of a lift pin insertion hole provided in a side wall of a rear frame, a curved ventilation groove is provided on a vacuum pump mounting surface of the rear frame, and the groove upper part is further provided. Is covered with the cover of the vacuum pump.

[0008]

By providing a curved groove, which is connected to the lift pin insertion hole provided on the side wall of the rear frame, on the vacuum pump mounting surface on the outer surface of the rear frame, the brush and the slip ring are prevented from interfering with cooling and discharge of abrasion powder. It is possible to prevent the infiltration of water and the like. Further, the work of assembling with the sealing component for closing the lift pin insertion hole as in the conventional generator can be omitted, and the work can be improved.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows an AC generator with a vacuum pump, wherein 1a is a rear frame of the AC generator, 1b is a front frame, 2 is a shaft of the generator, and shaft 2 is a rear frame 1a and a front frame 1b. Is supported by bearings 11 and 12 disposed inside the rear frame 1a,
A pair of slip rings 3 is attached to the shaft on the side.

Reference numeral 4 denotes a brush holder. A pair of brushes 5 are inserted in a brush housing portion of the brush holder 4, and the brushes 5 are urged by a spring 6 and slidably contact the slip ring 3. A pair of cores 13 are fixed to the shaft 2 at a substantially central portion thereof, and a field coil (not shown) is wound between the cores 13. The field coil includes a brush 5 and a slip ring 3.
A field current is supplied via the lead wires 15a and 15b. Reference numeral 16 is a cooling fan fixed to the side surface of the core 13, and 17 is a stator core around which an output winding is wound.

The shaft 2 projects from the rear frame 1a, and is pumped by a suitable method such as a spline.
Are combined. Reference numeral 21 is a vane that is slidably fitted into a plurality of vane insertion grooves 21a provided radially on the pump rotor 20.

Reference numeral 22 is a cover, and 23 is a casing.
The cover 22 and the casing 23 are fastened to the rear frame 1a with bolts 24.

The structure around the brush holder and around the ventilation groove of the embodiment will be described with reference to FIGS. 2 and 3.

FIG. 2 is a partial sectional view of the vicinity of the brush holder when the generator is assembled. The brush holder 4 and the brush 5 are shown in FIG.
The pin holes 8, 9 and 10 for inserting the brush lift pins p are provided in the. The brush 5 is lifted by the brush lift pin p so that it is stored in the brush holder 4. Reference numeral 7 denotes a slip ring waterproof and dustproof tubular cover arranged on the outer periphery of the slip ring 3.
The cylindrical cover 7 is formed of a synthetic resin material integrally with the brush holder 4.

By lifting the brush 5, the interference of the brush 5 with the slip ring 3 is eliminated, and the members such as the shaft 2 and the brush holder 4 can be incorporated without any trouble. After pulling out the brush lift pin p,
There is a possibility that muddy water may enter the brush holder 4 from the outside and the waterproofness of the slip ring 2 may be impaired. However, in this embodiment, the following structure is adopted.

A bent groove 1a1 is formed on the lift pin p insertion opening side of the lift pin hole 8 arranged on the side wall of the rear frame 1a, and the entrance of the bent groove 1a1 faces the ground direction (downward) in the vehicle mounting direction of the rear frame. I am doing it. Further, a vacuum pump cover 22 covers the axial opening of the bending groove 1a1.

When the generator rotates in such a structure, the negative pressure of the cooling fan 16 causes the air inlet 30 of the ventilation groove provided on the outer surface of the rear frame to pass through the brush lift pin holes 8 and 9 to reach the brush sliding portion. Outside air invades.

Here, since the outside air temporarily flows in the upward direction, heavy foreign matter, water, etc. are removed by gravity and the bent passage, and only air enters the slip ring cylindrical cover 7, and the brush 5 and the slip ring 3 are introduced. To cool at the same time.

Further, by sliding with the slip ring 3,
Brush abrasion powder of the brush 5 that has been scraped off is removed and scattered to the outside.

[0021]

The AC generator with vacuum pump of the present invention is as described above, and the effects are as follows.

Since the outside air is sucked into the slip ring side by the cooling fan and applied to the brush and the slip ring,
The temperature can be reduced, and the life of the brush can be significantly improved.

By ventilating the cooling fan side,
Brush abrasion powder can always be discharged to the outside.

Since the entrance of the outside air is directed downward and further bent, there is no risk of foreign matter entering.

A simple structure can be used without increasing the number of parts.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the entire embodiment.

FIG. 2 is a partial cross-sectional view showing a main part of the present invention.

FIG. 3 is a front view of a rear frame as seen from a vacuum pump mounting side.

[Explanation of symbols]

1a, 1b ... Frame element, 2 ... Shaft, 3 ... Slip ring, 4, 5 ... Brush holder, 7 ... Cylindrical cover,
8, 9, 10 ... Lift pin insertion hole, 20 ... Vacuum pump, p ... Brush lift pin.

Claims (2)

[Claims] 1. A brush provided with a slip ring provided on a shaft of a generator, and a brush holder for holding the brush. The brush, the brush holder and a side wall of a generator rear frame are provided with the generator. A brush lift pin insertion hole for lifting the brush so as not to interfere with the slip ring during assembly is provided, and the shaft projects from the rear frame,
A vacuum pump rotor is fixed to the shaft, a vane is embedded in the vacuum pump rotor, the vane and the vacuum pump rotor are housed in a casing, and an open end of the casing is sealed with a cover. An AC generator with a vacuum pump, characterized in that a curved ventilation groove is provided on the vacuum pump mounting surface of the rear frame starting from the lift pin insertion hole of the lift pin insertion hole provided on the side wall of the rear frame. AC generator. 2. The upper portion of the ventilation groove according to claim 1,
An alternator with a vacuum pump, which is covered with a vacuum pump cover.