JPS63234856A - Cooling structure of power generator of vehicle such as motor-bicycle or the like - Google Patents

Abstract

PURPOSE:To prevent a power generator from lowering in power generating efficiency, by cooling the generator directly by engine oil. CONSTITUTION:Oil is supplied from an oil pimp 10 to an oil path 9 in a crank case 2. The oil is then decompressed by an orifice 12 and led to a hollow section 13 inside the fixing boss A of a stator through an oil path 11 on the side of a cover 6. Further, the oil moves externally in the radial direction through an oil path 18 while receiving centrifugal force from a coupling member 4 and a rotor support section 16. It is released into the inside the cover 6, advancing through clearance 17 between a rotor 3a and a stator 3b and is returned to inside the crank case 2. The stator 33b and rotor 3a thereby raise temperature due to the heat by power generation, but they are cooled respectively with the oil flowing through the hollow section 13 inside the fitting boss A and the clearance 17. As a result, the temperature raise of rotor 3a and stator 3b can be controlled to a certain extent and the power generating efficiency can be kept excellently.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a cooling structure for a generator installed in an engine of a vehicle such as a motorcycle.

"Prior art and its problems" Usually, vehicles with an engine, such as motorcycles, are equipped with a generator connected to the engine, and the generator supplements the power consumed by the battery while the engine is rotating (in practice). 1977
-47243). A generator consists of a rotor that is attached to a rotating shaft such as a crankshaft, and a fixed stator that is placed inside or outside of the rotor. It also has a heat dissipation function that dissipates heat to.

Incidentally, in motorcycles, tricycles, etc., the space for arranging the engine and other equipment is limited, so not only the engine itself but also the generator are required to be smaller and lighter.

However, in the above generator, is it possible to generate electricity using means such as rotating the rotor at high speed? If an attempt is made to reduce the size and weight without decreasing the fins, the heat dissipation area will become smaller and the amount of heat dissipated will decrease as the members are made smaller, resulting in higher temperatures and lower power generation efficiency. For these reasons, there has been a limit to the reduction in size and weight of generators.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a cooling structure for a generator in a vehicle such as a motorcycle, which allows the generator to be made smaller and lighter in weight without reducing power generation efficiency.

"Means for Solving the Problem" The present invention provides a hollow part in the mounting boss part of a generator connected to a rotating shaft such as a crankshaft, communicates the hollow part with an oil supply source, and connects the hollow part to an oil supply source. The present invention is characterized in that an oil passage is provided on the side of the machine to communicate the hollow part with the gap between the rotor and the stator.

"Function" The oil supplied into the hollow part of the generator mounting boss is
There, it comes into contact with the rotor or stator placed inside the generator and cools the rotor or stator. Thereafter, the oil is guided to the gap between the rotor and stator through the oil passage formed on the side of the generator while being subjected to centrifugal force from the rotor side, and passes through the gap between the rotor and stator to the generator. Although the other side is open, when the oil passes through the gap between the rotor and stator, it is also directly cooled while coming into contact with them.

"Embodiment" An embodiment of the present invention will be described below with reference to the drawings.

First Embodiment FIG. 1 shows a first embodiment of the present invention. This example:
This is an example in which the present invention is applied to cooling an AC generator (alternating current generator) assembled to the engine of a motorcycle.

Reference numeral I in the figure represents a crankshaft, and the crankshaft 1 is rotatably supported by a plurality of shaft support parts formed in a crankcase 2. As shown in FIG. AC at the end of the crankshaft t
A generator (alternating current generator) 3 is provided.

The AC generator 3 includes a rotor 3a and a stator 3a disposed coaxially inside the rotor 3a with a slight gap therebetween. The rotor 3a is fixed via a stopper 5 to a collar 4b of a connecting member 4 attached to the end of the crankshaft l so as to rotate together with the end, and the stator 3b is bolted to an AC generator cover 6 that covers the AC generator 3. It has been fixed.

Reference numeral 9 denotes an oil passage formed integrally with the crankcase 2, and the base side of this oil passage 9 is connected to an oil pump IO. Further, 11 is an oil passage formed integrally with the cover 6, and this passage I! is formed to extend to the mating surface with the crankcase 2 so as to communicate with the oil passage 9 when the cover 6 is fixed in a normal position with respect to the crankcase 2 as shown in the figure. Also,
An orifice 12 is interposed on the crankcase 2 side of the connecting portion between the oil passage 9 and the oil passage 11.

The oil passage II is formed in an abbreviated shape to match the shape of the cover 6, and the tip of the oil passage 11 extending to the center of the cover 6 fits and supports the stator 3b of the cover 6 in a fluid-tight manner. The hollow part 13 of the boss part A is connected to the hollow part 13 of the boss part A. The hollow portion 13 of the mounting boss portion A is liquid-tightly closed on the outside by a lid member 14, while the inside is open.

Further, between the left side surface of the stator 3b in the figure and the right side surface of the connecting member 4 and rotor support part 16 in the figure opposing thereto, there is a space between the hollow part 13 and the rotor 3a and the stator 3b.
An oil passage I8 is formed that communicates with the gap 17 between the two. The side surface 4b of the connecting member 4 forming the inner wall of the oil passage I8 is formed into a tapered shape so as to quickly guide the oil outward. Further, the gap 17 between the rotor 3a and the stator 3b is formed continuously in the circumferential direction, and is open into the cover 6 on the side opposite to the side where the oil passage 18 is provided (the right side in the figure).

Next, the operation of the generator cooling structure described above will be explained.

When the crankshaft l rotates, the rotor 3a integrated with it rotates, but the stator 3b remains fixed to the AC generator cover 6 and does not rotate. That is, relative rotation occurs between the rotor 3a and the stator 3b, and power generation occurs between them.

On the other hand, oil is supplied from the oil pump IO to the oil passage 9 integrally formed in the crankcase 2. After the oil is depressurized in the orifice 12, it is passed through the oil passage 11 on the cover 6 side to the mounting boss of the stator. It is guided to the hollow part 13 in part A. The oil guided into the hollow portion 13 moves radially outward in the oil passage 18 while receiving centrifugal force from the connecting member 4 and the rotor support portion 16, and moves toward the outside in the radial direction within the oil passage 18.
It is opened into the cover 6 through a gap 17 between the stator 3a and the stator 3b. The oil released into the cover 6 is returned into the crankcase 2 from there.

During power generation by the AC generator, the stator 3b and rotor 3a each try to rise in temperature due to the influence of heat associated with power generation, but the stator 3b is connected to the hollow part 13 in the mounting boss A, the rotor 3a, and the stator 3b. Also, the oil passing through the gap I7 between the rotor 3a
are appropriately cooled by the oil passing through the gap 17, and as a result, it is possible to suppress the temperature rise of the rotor 3a and stator 3b beyond a certain level, and it is possible to maintain good power generation efficiency.

In addition, in the above embodiment, an orifice 12 is provided in the passage 9 on the crankcase side among the passages for sending oil into the AC generator 3, and reduced pressure oil is supplied to the passage 11 on the cover side. Therefore, even if the lid member 14 loosens for some reason and oil leaks, the amount of oil leakage can be kept to a small level.

m2 11 FIG. 2 shows a second embodiment of the present invention. The major feature of this example is that oil is supplied to the AC generator 3 by using an oil passage 22 integrated with the crankshaft, without providing a dedicated passage for supplying oil to the AC generator 3. This is the point I made.

That is, the bolt insertion hole 21 provided at the end of the crankshaft 1 and the crank $ 111 in a state extending to the vicinity thereof.
A small hole 23 communicates with the oil passage 22 integrally formed in the bolt insertion hole 21, and an orifice 24 is provided at the bottom of the bolt insertion hole 21.
Further, a through hole 26 is formed along the central axis in the bolt 25 that fixes the connecting member 4 to the end of the crankshaft I, and an extension f! is formed in the head of the bolt 25. is 25
a is provided in a protruding manner, thereby reducing the pressure of a portion of the oil supplied to the oil passage 22 of the crankshaft l as appropriate.
is leading to Note that an oil passage 18 is provided between the stator 3b, the connecting member 4, and the rotor support portion 16, as in the first embodiment, and the cover 6 does not have an oil passage formed therein.

Even with such a configuration, the stator 3b and rotor 3a can be directly cooled with oil, suppressing temperature rise, and maintaining good power generation efficiency.

In each of the above embodiments, the structure is such that the generator 3 attached to the end of the crank @I is cooled, but the shaft to which the generator to be cooled is attached is not limited to the crankshaft. , or another shaft, such as a shaft dedicated to supporting a generator connected to a crankshaft by a gear or the like, or a main shaft or a counter shaft.

Further, in each of the above embodiments, the rotor 3a and the stator 3
b are arranged on the outside and inside, respectively, but they may be arranged in reverse.

"Effects of the Invention" As explained above, according to the present invention, a generator attached to a rotating shaft such as a crankshaft can be directly cooled using oil for engine circulation, thereby improving the efficiency of the generator itself. Good cooling can be performed and a decrease in power generation efficiency due to temperature rise can be prevented.

As a result, the generator can be made smaller and lighter while maintaining a constant power generation capacity. Further, by reducing the size and weight of the generator in this way, it is possible to reduce the inertial weight of the crankshaft system to which the generator is attached, and the responsiveness of the engine can be improved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a part of an engine showing a first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a part of an engine showing a second embodiment of the invention. l...Crankshaft, 3...AC generator (alternating current generator), 3a...Rotor, 3b
・Old...Stator, 6...Cover, 9.11,
18: Oil passage, 13: Hollow part, I7: Gap, A: Old: Mounting boss part.

Claims (1)

[Claims] A rotor (3a) attached to the rotating shaft (1) and rotating integrally with the rotating shaft, and a stator (3b) disposed at a predetermined interval on the inside or outside of the rotor.
) in the mounting boss part (A) of the generator (3).
an oil passage (18) which communicates the hollow part with an oil supply source (10) and communicates the hollow part with the gap (17) between the rotor and the stator at the side of the generator; A cooling structure for a generator in a vehicle such as a motorcycle, characterized by being provided with.