JPH03273847A - Ac generator for vehicle - Google Patents

Abstract

PURPOSE:To make the power of a generator high by providing a cooling liquid passage for cooling a feed coil prior to a stator coil by a cooling liquid flowing in from an intake port of the cooling liquid by opening the intake port and a discharge port in a frame. CONSTITUTION:A cooling liquid supplied from a pump 63 under a pressure flows inside a generator from an inlet pipe 40 and passes through a hole 43 and it is made to branch in two systems of a first groove 45 and a second groove 46 in the downstream end of a communication hole of a metal bearing 22. The cooling liquid passing through the first groove 45 flows in the direction of an arrow of the figure through a gap between a feed coil 17 and a pole core 19, so as to cool down the feed coil. The cooling liquid running through the second groove 46 flows in the direction of an arrow of the figure, so as to cool down a commutator 50 and a regulator. Then, these cooling liquids join and flow through a gap 52 between a stator 14 and a pole core 18, so as to cool down a stator coil 16. According to this constitution, a heat is absorbed efficiently from the feed coil and the commutator prior to the stator coil.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vehicle alternator, and particularly to cooling of a vehicle alternator.

(Prior Art) As the electrical load of vehicles increases and the environments in which they are used become wider, there has been a demand for vehicle generators with high output and good environmental resistance.

For example, the vehicle alternator disclosed in Japanese Patent Application Laid-Open No. 62-189941 uses a cooling liquid to directly cool the feed coil and stator coil, which are heat sources inside the generator, as a cooling device to achieve high output. do.

(Problems to be Solved by the Invention) However, such conventional vehicle AC generators
Since the stator coil is actively cooled rather than the feed coil, the feed coil, which must be sufficiently cooled in order to achieve high output, is not sufficiently cooled.

That is, as shown in FIG. 3, the space between the stator coil 4 and rotor 5 is cooled by the cooling liquid introduced into the frame 3 from the inlet part 2 of the generator 1, and then the feed coil 6 is cooled, and the space between the rotor 5 and the feed coil is cooled. The coolant is discharged in the direction of the arrow from the outlet section 8 at the front of the frame 3 with almost no flow of the coolant in the minute gap 7 between the coils 6. Therefore, considering that the excitation current decreases due to a rise in the temperature of the feed coil 6, it is necessary to encourage cooling of the feed coil 6 in order to improve the output of the generator. 4 is preferentially cooled, and the feed coil 6 is cooled in a state in which the cooled hot liquid from which heat has been removed remains. Therefore, the cooling effect of the feed coil 6 was insufficient.

Furthermore, a minute gap 9 between the stator coil 4 and the rotor 5
The loss of rotor driving force increases due to the action of shear force due to the viscosity of the coolant in It is conceivable that the viscosity of the coolant may be lowered by

However, enlarging the minute gap 9 is not preferable in terms of the performance of the generator, and the lowest temperature and highest viscosity coolant cooled in the coolant circuit 10 outside the generator first flows into the minute gap 9 from the inlet section 2. As a result, power loss was relatively large.

The present invention was made to solve these problems, and the feed coil is cooled by cooling the feed coil with priority over the stator coil using a cooling liquid introduced into the generator frame. It is an object of the present invention to provide a vehicle alternator which is designed to increase the output of the generator and reduce power loss.

(Means for Solving the Problems) To achieve this, the vehicular alternator of the present invention includes a shaft housed inside a frame and rotatably mounted, a ball core fixed to the shaft, and a ball core fixed to the shaft. It is equipped with a wound feed coil that is excited by an exciting current, a stator core that is fixed at an outer circumferential position facing the feed coil, and a stator coil that is wound around the stator core. This is a vehicle alternator that cools the inside of the generator, and the frame has a coolant inlet and a coolant outlet. The invention is characterized in that a coolant flow path is configured to give priority to cooling.

(Function) According to the vehicular alternator of the present invention, the flow path of the coolant introduced into the generator is connected to two
The system is branched into two systems, and the feed coil is cooled by the cooling liquid flowing through the flow path of one system, and the rectifier is cooled by the cooling liquid flowing through the flow path of the other system. Since the stator coil is cooled by these combined cooling liquids, a large amount of heat is efficiently removed from the feed coil and the rectifier in priority to the stator coil, thereby increasing the output of the generator.

(Example) Embodiments of the present invention will be described below based on the drawings.

First, the structure of the alternator will be explained based on FIG. 1, and then the cooling system of the alternator will be explained in detail.

In FIG. 1, the inner periphery of the front frame 12 and rear frame 13, which are fixed to each other by bolts 10, etc., includes:
As is well known, the stator 14, which is composed of a stator core 15 and a stator coil 16 wound around the stator core 15, is fixed.

A feed coil 17 for generating an electromotive force in the stator coil 16 by electromagnetic induction is wound around a metal bobbin and fixed by being sandwiched between a pair of ball cores 18 and a boss portion 19. A shaft 20 that mechanically fixes the ball core 18 and boss portion 19 is rotatably supported by bearings 21 and 22.

A pulley 25 to which rotational driving force from an engine (not shown) is transmitted is fastened and fixed to the front end of the shaft 20 by a nut 26 and a washer 27.

Next, the cooling system will be explained.

An inlet vibrator 40 for introducing cooling fluid into the generator is attached to the bottom of the alternator frame 13. Further, an outlet vibrator 41 is attached to the front frame 12 for discharging coolant after cooling.

In the inner peripheral part of the metal bearing 22 of the shaft 20 provided in the rear frame 13, there is a hole 4 through which coolant is introduced from the outside of the generator from an inlet vibe 40 in the direction of arrow a in the figure.
3 is formed, and a communication hole 44 communicating with this hole 43 is communicated with both ends of the metal bearing 22 through a first groove 45 and a second groove 46.

In detail, the metal bearing 22 has a communication hole 44 which is opened in the inner circumferential wall surface of the metal bearing 22 and communicates with the hole 43, as its development view is shown in FIG.
A first groove 45 that opens toward the front end and a second groove 46 that opens toward the rear end are formed in a figure-7 shape in the orthogonal direction from the exit portion of No. 4. The outlet portion of the communication hole 44 opens at the upstream confluence of the first groove 45 and the second groove 46 .

The coolant flow path passing through the first groove 45 is the only one formed between the outer periphery 18a of the boss portion of the ball core 18, the inner periphery 47 of the claw portion, the rear frame 13, and the feed coil 17 that is tightly fixed in one type of pilot. pass through the gap. The coolant flow path passing through the second groove 46 passes through a rectifier 50 installed between the rear frame 13 and the rear cover 48 and a regulator (not shown). The downstream part of the coolant flow path branched by the first groove 45 and the second groove 46 merges as shown by the arrow C in the first figure, and then the stator 14, the ball core 18, and the ball core 1
9, and is further connected to the exit vibe 41 in the direction of arrow d in the figure.

The coolant discharged from the outlet vibrator 41 is transferred to a heat exchanger 61 and a tank 62 of the coolant circuit 11 provided outside the generator.
, flows in the direction of the illustrated arrow in the piping connecting the pump 63.

Communication hole 44 and first groove 4 formed in metal bearing 19
5 and the second groove 46, the hole diameter, shape, etc. are determined so that the required flow rate will flow depending on the output of the generator, the amount of heat generated by the feed coil 17, stator coil 16, rectifier 50, and regulator, the type of coolant, etc. It is possible to freely and appropriately set the groove width, groove depth, groove angle (θ shown in FIG. 2), etc.

The coolant pumped from the pump 63 flows into the generator from the inlet vibrator 40 and passes through the hole 43 to the first groove 45 and the second groove 4 at the downstream end of the communication hole 44 of the metal bearing 22.
The cooling liquid passing through the first groove 45 flows in the direction of the arrow shown in the figure through the gap between the feed coil 17 and the ball core 19 to cool the feed coil 17. Second
The coolant flowing through the groove 46 flows in the direction of the arrow shown in the figure to cool the rectifier 50, the regulator, and the like. Then, these coolants merge, and the combined coolant flows through the gap 52 between the stator 14 and the ball core 18 to cool the stator coil 16, and the coolant that has taken heat from the stator coil 16 is It is discharged from the outlet vibrator 41 to the outside. The coolant flowing through the cooling passage 60 is cooled by the heat exchanger 61 and returned to the tank 62 . and pump 63 from tank 62
The coolant pumped up by the pump flows into the generator from the inlet vibrator 40 and circulates through the cooling circuit as described above.

According to the above configuration, the coolant cooled most in the coolant circuit 11 outside the generator is pumped up from the tank 62 by the pump 63 and flows into the generator from the inlet vibe 40. This cooled coolant passes through the hole 43, a communication hole 44 formed in the metal bearing 22, and is branched into a first groove 45 and a second groove 46, and flows into the generator.

For this reason, since the feed coil 17, which is thick and affects the performance of the generator, and the rectifier 50, which generally has low heat resistance, are cooled by the coolant coolant, the feed coil 17
Since the electric resistance of the rectifier 50 is effectively reduced, the excitation current is increased, and the performance of the generator can be improved, and since the rectifier 50 is maintained at a lower temperature, the heat resistance of the rectifier 50 is also improved.

The low-viscosity coolant that has been heated by cooling the feed coil 17 and the rectifier 50 flows into the minute gap 52 between the ball core 18 and the stator 14, so that it is heated by cooling the feed coil 17 and the rectifier 50. Reduces power loss due to applied shear forces. In this case, the stator 14 has good heat resistance against high temperatures in each part of the generator inside the generator, and the temperature of the stator 14 has little effect on performance, so almost no problem occurs. Therefore, with such a configuration of the coolant flow path, it is possible to exhibit the best cooling efficiency and improve the performance of the generator, and at the same time, it is possible to reduce the driving force for rotating the shaft 20 as a rotor.

In the embodiment described above, the coolant flow path was branched into two channels by the first and second grooves formed in the metal bearing, but in other embodiments, the coolant could be routed before and after the generator by drilling holes in the carrier frame. The coolant flow path may be configured to branch. Furthermore, if the rectifier, regulator, etc. are not directly cooled with liquid, the cooling liquid may be made to flow around the feed coil without being branched. Furthermore, the coolant circuit can also use a power steering pump, a water pump, etc., without providing a dedicated pump.

(Effects of the Invention) According to the vehicular alternator of the present invention, since the feed coil is cooled preferentially to the stator coil by the cooling liquid introduced into the generator, the feed coil that requires cooling the most is cooled. This makes it possible to cool the generator with the lowest temperature coolant, improving the output of the generator, and since the relatively high temperature coolant flows into the gap between the ball core and stator core, the rotational driving force of the shaft is increased due to its low viscosity. This has the effect of reducing the driving force of the generator.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a vehicle alternator according to an embodiment of the present invention, FIG. 2 is an expanded enlarged view showing the inner peripheral surface of the metal bearing, and FIG. 3 is a conventional vehicle alternator. FIG. 2...Front frame, 3...Rear frame, 5...Stator core, 6...Stator coil, 7...Feed coil, 8...Ball core, 9...Boss part, O. ... Shaft, 0... Inlet vibe (cooling fluid intake), 1... Outlet vibe (cooling fluid discharge port), 3... Hole (cooling fluid flow path), 4... Communication hole (cooling fluid flow path),... 5...first groove (coolant flow path), 6...second groove (coolant flow path). #iJ-end-side-row-a-to-i-rule-1- Fig. 2

Claims (1)

[Claims] (1) A shaft housed inside the frame and rotatably mounted, a ball core fixed to the shaft, a feed coil wound around the ball core and excited by an exciting current, and a shaft facing the feed coil. A vehicular alternator comprising a stator core fixed at an outer peripheral position and a stator coil wound around the stator core, and cooling the inside of the generator by circulating a cooling liquid inside the frame, the AC generator comprising: a stator core fixed at an outer peripheral position and a stator coil wound around the stator core; Open the liquid inlet and coolant outlet,
An alternator for a vehicle, characterized in that a coolant flow path is configured to cool at least the feed coil with priority over the stator coil by the coolant flowing in from the coolant inlet.