JPS6318433B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is applied to a retarder for a vehicle. The present invention relates to a cooling device for a retarder, which is a deceleration brake for a vehicle. In particular, it relates to improvements in cooling devices for electromagnetic retarders.

[Conventional technology]

Mainly by downsizing automobile engines, the so-called engine braking effect becomes smaller. As a countermeasure to this problem, the applicant filed a patent application in Japanese Patent Application No. 173,516/1982 for a device that improves braking force by attaching an electromagnetic retarder to the engine. This includes a magnetic rotor mounted on the engine crankshaft, an excitation coil that applies magnetic force to the rotor, and a short-circuit ring that short-circuits the current generated due to changes in the lines of magnetic force between the rotor and the magnetic rotor. This device consists of a retarder unit. Since the rotor of this device is simply a magnetic material, it can also be used as a flywheel or other rotating body, and the excitation coil and heat-generating short-circuit ring are provided in the fixed body.

The present applicant filed Japanese Patent Applications No. 56-173223 to No. 56-173225 for the above-mentioned electromagnetic retarder cooling device. In the above-mentioned cooling system, the short-circuit ring of the retarder unit is formed by an annular pipe, and engine cooling water or lubricating oil is circulated as a cooling medium through the pipe to cool the heat-generating short-circuit ring.

FIG. 1 is a block diagram of a conventional retarder cooling device. In FIG. 1, a flywheel 5 pivotally attached to a crankshaft 3 between an engine 1 and a transmission 2 is made of a magnetic material. Several retarder units 7 are attached to the flywheel housing 6. A large number of teeth 9 are formed around the flywheel 5. This flywheel 5 acts as a retarder rotor, and the retarder unit 7 is attached to teeth 9 of this flywheel 5.
Acts as a field that excites the

FIG. 2 is an enlarged cross-sectional structural diagram of a conventional cooling device. In the retarder unit 7, an excitation coil 10 is wound around a core 13. 14 is an insulating winding frame. The tip of the core 13 opposes the teeth 9 and acts electromagnetically. A short circuit ring 15 of a conductor is fitted into the core 13. This short-circuit ring 15 is constituted by a small-diameter pipe, and one end of the short-circuit ring 15 is connected to a cooling water inlet gearing 17, and the other end of the short-circuiting ring 15 is connected to a cooling water outlet gearing 18.
These gears 17 and 18 are connected to the engine 1.
Connected to the radiator cooling system (not shown).

In a retarder with such a configuration, the crankshaft 3
When the exciting coil 10 is excited by a current during rotation, the core 13 is magnetized and lines of magnetic force are generated between the core 13 and the teeth 9 of the flywheel 5. Since the teeth 9 move one after another relative to the core 13 as the crankshaft 3 rotates, this current turns into heat in the short-circuit ring 15 and provides a braking force to the flywheel 5. The short circuit ring 15 is cooled by cooling water circulating in the pipe.

On the other hand, Japanese Unexamined Patent Publication No. 54-93745 discloses a technique for cooling heat generated by eddy currents using a heat pipe. Further, Japanese Utility Model Application Publication No. 53-35352 discloses a technology for generating heat by eddy currents in a rotating machine and cooling it by heat pipes.

[Problem that the invention seeks to solve]

The conventional cooling device described above requires a small diameter pipe to be stretched around the retarder unit.
There is a possibility that the connecting portion of the pipe may be damaged, and furthermore, due to foreign matter adhering to the inner surface of the pipe, there is a risk that the cooling medium will not circulate properly during long-term use.

That is, since the short-circuit ring 15 shown in FIG. 2 is constituted by a small-diameter pipe, there is a risk that the connecting portions with the gears 17 and 18 may be damaged due to vibration. In addition, during the process of cooling the short circuit ring 15 over a long period of time, water scales may adhere to the inside of the pipe, making it difficult to circulate the cooling water properly, and there is a possibility that the cooling efficiency may deteriorate.

In addition, the technologies disclosed in the above two publications both cool the heat generated in a metal body by eddy current using a heat pipe installed in contact with the metal body, and the heat generated in the metal body by eddy current is cooled by a heat pipe installed in contact with the metal body. Since it involves the movement of heat, it has the disadvantage of poor cooling efficiency.

The present invention solves the above-mentioned problems, and aims to provide a retarder cooling device that has high cooling efficiency, a low failure rate for long-term use, and high reliability.

[Means for solving problems]

The present invention is characterized in that the short-circuit ring of the retarder unit is formed by a metallic heat pipe, and the heat pipe is provided with means for guiding the engine cooling medium to the end thereof.

Note that the cooling medium is preferably engine cooling water or lubricating oil.

As used herein, "heat pipe" means
A small amount of volatile liquid is sealed in a metal tube by venting air.The purpose is to transfer heat by absorbing and releasing latent heat through evaporation and condensation of this liquid. It is capable of transporting a large amount of heat with a small temperature difference, has a thermal conductivity of several thousand orders of magnitude compared to metal heat conduction, and can achieve low loss heat transfer.

[Effect]

A retarder installed in a vehicle has an excitation coil that is energized by an electric current while the crankshaft is rotating.
The core becomes magnetized and creates lines of magnetic force between it and the teeth provided on the outer periphery of the flywheel. As the teeth move one after another relative to the core due to the rotation of the crankshaft, heat is generated in the short circuit ring.

The generated heat is conveyed to the cooling water gallery through the heat pipes constituting the short-circuit ring, and is radiated to the cooling water via the cooling fins for cooling. In the present invention, the heat generated in the short-circuit ring itself is constructed by constructing the short-circuit ring with a heat pipe, and a cooling medium is introduced into the heat pipe to cool the heating element itself. Therefore, a high cooling effect can be obtained.

〔Example〕

Next, an apparatus according to an embodiment of the present invention will be explained based on the drawings. FIG. 3 is a cross-sectional structural view of a cooling device according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line A-A'. 3 and 4, a characteristic configuration of the present invention is that a heat pipe short-circuit ring 20 is fitted in place of the pipe short-circuit ring 15 shown in FIG. 2, and one end of this short-circuit ring 20 is connected to the cooling water. It extends into the gear gallery 21, and has a cooling fin 22 attached to one end thereof. The cooling water gear gallery 21 is connected to a cooling system of a radiator of the engine 1 (not shown).

In the device having such a configuration, the heat generated in the short-circuit ring 20 of the core 13 is carried to the cooling water gallery 21 by the heat pipe and cooled through the cooling fins 22. Thereby, the short circuit ring 20 can be cooled without directly cooling the core 13 with cooling water.

In the above example, the cooling water gallery 21 is provided for each retarder unit 7, but one common cooling water gallery 21 is provided for several retarder units 7, and within this common cooling water gallery 21, It is also possible to extend one end of several heat pipes together.

Furthermore, engine lubricating oil may be used instead of engine cooling water.

〔Effect of the invention〕

As described above, according to the present invention, the short-circuit ring of the retarder unit is formed of a heat pipe, and the engine cooling medium is guided to one end of the heat pipe, so that the retarder unit can be It is no longer necessary to lead the cooling medium through a pipe to the core, there is no risk of liquid leakage or pipe clogging, and a highly reliable retarder cooling system with high cooling efficiency and low failure rate over long periods of use can be obtained. .

In particular, if one end of the short-circuited rings of several retarder units are collectively guided to one cooling water gallery for cooling, a compact cooling device that does not take up much space can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a cooling device for a conventional retarder.
FIG. 2 is an enlarged cross-sectional structural diagram of a conventional cooling device. Third
The figure is a cross-sectional structural diagram of a cooling device according to an embodiment of the present invention. FIG. 4 is a sectional view taken along line A-A' shown in FIG. 3. DESCRIPTION OF SYMBOLS 1... Engine, 2... Transmission, 3... Crankshaft, 5... Flywheel, 6... Flywheel housing, 7... Retarder unit, 9...
... Tease, 10 ... Excitation coil, 13 ... Core, 14 ... Insulating winding frame, 15, 20 ... Short circuit ring,
17...Cooling water inlet gear, 18...Cooling water outlet gear, 21...Cooling water gear, 22...
cooling fins.

Claims (1)

[Claims] 1. A magnetic rotor that is mounted on the crankshaft of an engine, an excitation coil that applies magnetic force to this rotor, and a change in the lines of magnetic force that occurs between this rotor due to the rotation of this rotor. and a retarder unit including a short-circuit ring that short-circuits a current flowing through the engine, wherein the short-circuit ring is formed by a metallic heat pipe, and means is provided for guiding the cooling medium of the engine to an end of the heat pipe. A retarder cooling device featuring: 2. The retarder cooling device according to claim 1, wherein the cooling medium is engine cooling water. 3. The retarder cooling device according to claim 1, wherein the cooling medium is engine lubricating oil.