JPH0345964B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a retarder for an automobile, and in particular, the retarder is composed of a generator, and when the generator generates electricity, it absorbs externally applied torque to obtain braking force, and The present invention relates to an automobile retarder in which a load resistor is connected to the armature coil of a generator, and the load resistor converts the generated output into heat.

Retarders conventionally used to brake automobiles use eddy currents, which generate eddy currents in the rotor by rotating the rotor in a magnetic field formed by a stator coil. kinetic energy was converted into thermal energy. Such conventional eddy current type retarders have the disadvantage of being large in size and weight. Furthermore, since the rotor is equipped with cooling fins, the fins cause windage damage even when braking is not performed.
The drawback was that it worsened fuel efficiency.

In view of these problems, a retarder consisting of a generator has been proposed. This generator is composed of, for example, an inductor type generator, and its rotor is also used as the flywheel of the engine, so that the retarder can be constructed compactly. However, in conventional retarders of this kind, the armature coil of the generator constituting the retarder is connected to a load resistor, and the generated output is converted into heat by the load resistor. Therefore, it is necessary to cool this load resistance by some kind of cooling means.

In the past, water cooling was used for cooling, but this required a large-scale cooling system and was not reliable. It is also possible to adopt an air cooling system instead of a water cooling system, but when adopting such an air cooling system, a forced cooling fan is required, which again requires a large-scale device.

The present invention has been made in view of these problems, and provides an automobile retarder that effectively cools a load resistor connected to an armature coil without using a special cooling device. The purpose is to

The invention will now be explained with reference to the illustrated embodiments. FIG. 1 shows an engine 1 equipped with a retarder according to a first embodiment of the present invention, and this engine 1 is composed of, for example, a diesel engine. A flywheel housing 2 is provided on the rear side of the engine 1, and a flywheel 4 fixed to a crankshaft 3 is housed within the housing 2 (see FIG. 2). Further, a transmission 5 is disposed on the back side of the flywheel housing 2, and is configured to change the rotational speed of the engine 1 to an appropriate value and transmit it to the driving wheels via a propeller shaft 6.

Next, regarding the structure of the retarder provided in this engine 1, as shown in FIG. An inductor magnetic pole 7 is provided. And this magnetic pole 7
The flywheel 4 provided with the rotor B of the inductor type generator A constitutes the rotor B of the inductor type generator A, and the generator A constitutes the retarder of the automobile. Cases 8 are provided at the top and bottom of the housing 2, and an inductor generator A is installed in the case 8.
stator C is stored.

As shown in FIG. 3, this stator C includes a plurality of pole cores 9 arranged in the circumferential direction of the flywheel 4. The lower end of the pole core 9 faces the inductor magnetic pole 7 via a minute air gap, and the upper end faces the stator yoke 10.
It is fixed to the cover plate of the case 8 via. An armature coil 11 and a field coil 12 are wound around the pole core 9, respectively. Note that the armature coil 11 is wound around two pole cores 9, whereas the field coil 12 is wound around each pole core 9 one at a time.

An armature coil 11 constituting the stator C and housed in the case 8 is connected to a load resistor 13 as shown in FIG. This load resistance 13
is designed to be cooled by exhaust gas from the engine 1. That is, an exhaust manifold 14 is connected to the exhaust port of the cylinder head of the engine 1, and an exhaust pipe 15 is further connected to the exhaust manifold 14. A muffler 16 is connected to the end of this exhaust pipe 15.
A load resistor 13 is housed within this muffler 16 as shown in FIG. Note that the load resistor 13 is the fifth
As shown in the figure, the muffler 16 is composed of a resistance wire wound in a coil shape, and the resistance wire is cooled by coming into contact with exhaust gas.

Next, the operation of this automobile retarder having the above structure will be explained. For example, when a car is going down a long slope, the retarder switch installed in the driver's seat is turned on. Then, a current flows from the battery 25 to the field coil 12 of the inductor type generator A via the controller 24 shown in FIG.
Coil 12 will be energized. As shown in FIG. 3, the field coil 12 magnetizes two pole cores 9 in opposite directions, and a pair of pole cores 9 around which a common armature coil 11 is wound have different polarities. It becomes magnetized like this. Therefore, at a certain moment, a magnetic circuit 22 as shown by the dotted line in FIG. 3 is formed, and when the flywheel 4 rotates and the inductor magnetic pole 7 moves by an angle corresponding to the pitch of the pole core 9, A magnetic circuit 23 as shown by the chain line in FIG. 3 is formed.

The magnetic fluxes passing through these magnetic circuits 22 and 23 both interlink with the armature coil 11, and
The directions of the magnetic fluxes passing through the two magnetic circuits 22 and 23 are reversed. Therefore, due to this change in magnetic flux, an electromotive force is induced in the armature coil 11,
This inductor type generator A will generate electricity. This means that the engine 1 or the vehicle drives the flywheel 4, and the work done from the outside at this time absorbs torque and provides braking force. Therefore, the vehicle receives a braking force due to the power generated by the inductor type generator A, and the vehicle is decelerated. The generated output at this time is exchanged into heat by the load resistor 13 and consumed.

This load resistor 13 is arranged in a muffler 16 connected to the end side of the exhaust pipe 15 as shown in FIG. 4, and is composed of a resistance wire wound into a coil shape as shown in FIG. ing. Therefore engine 1
The heat of this resistor 13 is taken away by the exhaust gas discharged by the resistor 13, and the resistor 13 is cooled. Generally, when the retarder is operated, the accelerator pedal is not depressed at all, and the fuel supplied to the engine 1 is substantially zero. Therefore, the amount of heat radiated from the engine 1 is small, and the temperature of the exhaust gas is extremely low. Furthermore, this load resistance 13 is connected to the exhaust pipe 15.
It is arranged in a muffler 16 connected to the end side of the muffler 16. That is, since the load resistor 13 is arranged near the atmosphere discharge part of the exhaust system, this also lowers the temperature of the exhaust gas. Therefore, with such a configuration, the load resistor 13 is sufficiently cooled by the exhaust gas.

Incidentally, when the car is being driven normally, the temperature of the exhaust gas inside the muffler 16 depends on the position of the muffler 16 in the exhaust system,
150℃ depending on the load condition of engine 1
~400°C, and when the engine 1 is operated at full load, the temperature of the exhaust gas inside the muffler 16 may reach 500°C to 600°C. Therefore, when the accelerator pedal is released (when the retarder is activated) when the temperature of the engine 1 is extremely high, such as immediately after climbing a hill, the temperature of the exhaust gas flowing inside the muffler 16 will be about 300°C. However, if the accelerator pedal is released after normal driving, the temperature of the exhaust gas will drop to about 80°C to 40°C due to the cooling effect up to the muffler 16.

On the other hand, as the load resistance 13 rises to a maximum of about 800°C as the retarder operates, conventionally a strict heat-resistant cover was installed and forced cooling was performed, but as described above, Since the temperature of the exhaust gas is sufficiently lower than the heat generation temperature of the load resistor 13 at least when the accelerator pedal is released (when the retarder is activated), the load resistor 13 is efficiently cooled. In addition, load resistance 1
Since the maximum temperature of the exhaust gas that comes into contact with the load resistor 13 is lower than the heat generation temperature of the load resistor 13, the load resistor 13 does not become overheated due to contact with the exhaust gas.

As described above, in the automobile retarder according to this embodiment, the rotor is the flywheel 4 of the engine 1.
It consists of an inductor type generator A, which is also used as an inductor type generator A, and the braking force is obtained from the torque that the generator A absorbs when generating electricity. When power is generated, the load resistor 13 converts electrical energy into thermal energy and generates heat.
At this time, the load resistor 13 is cooled by the exhaust gas from the engine 1. Therefore, no special cooling device is required, and no heat countermeasures are required due to the heat generated by the load resistor 13. Therefore, it becomes possible to construct a retarder for an automobile more compactly.

Next, a second embodiment of the present invention will be described with reference to FIGS. 6 to 8. In this embodiment, the same reference numerals are given to the parts corresponding to those of the first embodiment, and the explanation of the parts having the same configuration is omitted, and the explanation of the first embodiment is used.

The feature of this second embodiment is that a branch pipe 17 is provided in the exhaust pipe 15, and a resistance box 18 is connected to this branch pipe 17. A load resistor 13 connected to the armature coil 11 of the inductor type generator A constituting the retarder is disposed within the resistance box 18. Furthermore, in this embodiment, switching valves 19 and 20 are attached to the inlet portions of the exhaust pipe 15 and branch pipe 17, respectively.

In the above configuration, when the retarder is not used for normal running, the switching valve 19 is opened and the switching valve 20 on the branch pipe 17 side is closed, as shown in FIG. . Then, the exhaust gas generated by the engine 1 is guided from the exhaust pipe 15 to the muffler 16 without passing through the branch pipe 17, and is then discharged into the atmosphere. On the other hand, when operating the retarder to obtain braking force, the switching valve 19 is closed and the switching valve 20 on the branch pipe 17 side is opened as shown in FIG. Exhaust gas is passed through the branch pipe 17 to the resistance box 18
The load resistor 13 inside the resistance box 18 is cooled by the exhaust gas. Furthermore, resistance box 1
The exhaust gas that has cooled the resistor 13 in the exhaust pipe 8 passes through the exhaust pipe 15 again, passes through the muffler 16, and is discharged to the outside.

As described above, in the automobile retarder according to the present embodiment, since exhaust gas does not pass through the resistance box 18 in which the load resistor 13 is housed during normal driving, carbon may not accumulate on the load resistor 13. Or corrosion caused by exhaust gas can be prevented. Furthermore, during normal driving, the branch pipe 17 is closed by the switching valve 20, and the valve 19 is opened so that the exhaust gas is directly discharged from the exhaust pipe 15. A pressure increase can be prevented, and the load on the engine 1 can be reduced. Furthermore, according to this embodiment, the eighth
As shown in the figure, a pair of switching valves 19 are provided in the exhaust pipe 15 and the branch pipe 17, respectively.
By closing 20, the exhaust system of the engine 1 can be closed, thereby allowing the exhaust brake to be operated. Therefore, it is also possible to selectively use braking by the retarder and braking by the exhaust brake.

Next, a modification of the second embodiment will be explained with reference to FIGS. 9 to 11. In this modification as well, parts corresponding to those in the second embodiment are given the same reference numerals, and descriptions of parts having the same configuration will be omitted. The feature of this modification is that instead of the pair of switching valves 19 and 20, a single three
A direction switching valve 21 is used, and this valve 21 is connected to a branch portion between the exhaust pipe 15 and the branch pipe 17.

Even in such a modified example, during normal driving, the exhaust pipe 15 and branch pipe 17 are connected as shown in FIG.
The exhaust gas is directly communicated from the exhaust pipe 15 to the muffler 16. On the other hand, when operating the retarder, the three-way switching valve 21 is switched as shown in FIG. Load resistance 1 in 18
3 to be cooled. When the exhaust brake is operated, the three-way switching valve 21 is switched as shown in FIG. 11 to close the exhaust system. Therefore, even in such a modified example, it is possible to achieve substantially the same effects as in the second embodiment.

As described above, the present invention relates to an automobile retarder in which a load resistor is attached to the exhaust system of the engine to which the retarder is attached, and the load resistor is cooled by engine exhaust gas during braking. be. Therefore, according to the present invention, it is possible to effectively cool the load resistance connected to the armature coil that constitutes the retarder without requiring a special cooling system, and the retarder can be configured compactly and simply. It becomes possible to do so.

[Brief explanation of drawings]

FIG. 1 is a side view of an engine equipped with a retarder according to a first embodiment of the present invention, FIG. 2 is a perspective view of the retarder, FIG. 3 is an expanded longitudinal sectional view of the stator of the retarder, and FIG. 4 is a side view showing the cooling device for the retarder, FIG. 5 is an enlarged sectional view of the same essential part, FIG. 6 is a front view of the cooling device for an automobile retarder according to the second embodiment of the present invention, and FIG. 8 and 8 are front views showing the operating state of this cooling device, FIG. 9 is a side view of a cooling device for an automobile retarder according to a modification of the second embodiment, and FIGS. 10 and 11 are It is a side view of the same operating state. In addition, in the symbols used in the drawings, 2... flywheel housing, 4... flywheel, 7... inductor magnetic pole, 9... pole core, 11... armature coil, 12... field coil, 13... Load resistance, 15...Exhaust pipe, 16...
...muffler, 17...branch pipe, 18...resistance box, 1
9, 20...Switching valve, 21...3-way switching valve.

Claims (1)

[Claims] 1. A retarder for an automobile having a generator A and a load resistor 13, wherein the generator A absorbs the running energy of the automobile and generates electricity, and the load resistor 13 is an electric motor of the generator A. Connected to the child coil 11, the exhaust gas conduit 15,1 of the engine 1
An automobile retarder that is installed in a vehicle and cooled.