JPS59220100A - Retarder brake force controller of vehicle - Google Patents

Abstract

PURPOSE:To obtain a brake in response to the rotating speed of an engine by converting a current generated in a generating coil to heat and controlling the resistance value of a variable resistor which dissipates the heat in response to the rotating speed of the engine. CONSTITUTION:When a retarder switch 8 becomes ON state, an exciting current is flowed from a battery 7 to an exciting coil 11, and tees 3 and a core 12 of a flywheel 4 becom attracting state to each other. Accordingly, a brake force is produced at the flywheel 4. On the other hand, since lines of magnetic force from the core 12 is sequentially crossed by the tees 3 by the rotation of the flywheel 4, an electromotive force is generated at the coil 9, and the current is flowed through an output line 15 to a heat sink unit 10. At this time the controller 14 controls the resistance value of unit 10 in response to the rotating speed of the engine. In this manner, the brake force suitable in response to the traveling state of the vehicle can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a braking force control device for an electromagnetic retarder, which is a deceleration brake for a vehicle.

(Description of the Prior Art) Generally, in a large vehicle, when descending on a long plank road using only the engine brake and the service brake, there is a risk that the braking force of the service brake will decrease if the allowable limit of the brake is exceeded.

Therefore, in order to reduce the burden on the regular brake and maintain its performance even after long periods of use, an exhaust brake, hydraulic or electromagnetic reducer is used in combination as an auxiliary deceleration brake or rake.

However, in recent years, vehicle engines have been made smaller and lighter due to the need to improve fuel efficiency, and as a result, the braking force of the engine brake or exhaust brake described above has decreased, which has resulted in the need for a more powerful auxiliary deceleration brake. It became necessary to establish one.

In order to solve this problem, the applicant invented a new electromagnetic retarder as a deceleration brake for vehicles, and filed a patent application in 1983.
A patent application was filed under -173516. This electromagnetic retarder has a retarder rotor that is a flywheel that is mounted on a crankshaft between an engine and a transmission, and a retarder unit that includes an excitation coil that excites the flywheel and a short-circuit ring in the housing of the flywheel. Even if the total displacement decreases as engines become smaller and lighter, the same braking force as conventional engine brakes can be obtained.

Further, since the electromagnetic retarder described above converts the rotational energy of the crankshaft into thermal energy by the short-circuit ring wound around the core of the retarder unit during braking, it is necessary to cool the short-circuit ring during braking.

The applicant filed a patent application for this cooling device in Japanese Patent Application No. 56-1732.
22 Special i 1973-173223, patent application 1982-1732
24, Japanese Patent Application No. 56-173225 and Japanese Patent Application No. 57-2
A patent application was filed for 08020.

In addition, to further enhance the cooling effect of the retarder unit, the short-circuit ring is replaced with a generating coil, and a radiator made of an electric resistor that converts the current generated in the generating coil into heat and radiates the heat is connected to the generating coil. A separate application was filed on the same day as this application for a retarder heat dissipation device.

However, in both the short circuit ring and the heat radiator, the amount of heat generated by the flowing current depends on the respective resistance values.

Therefore, if the resistance values of the short-circuit ring and the radiator are set to uniform resistors, the amount of heat generated by the short-circuit ring and the radiator will change depending on the engine rotation speed, and the retarder with low cooling capacity will change when the engine rotation speed is extremely high. There is a risk of burning out the core of the retarder unit and the excitation coil during braking. In addition, when heat is radiated by a radiator connected to the generator coil, by increasing the resistance value of the radiator, sufficient heat radiation can be achieved during braking at high engine speeds; In the absence of a retarder, the current generated in the generator coil was small and the retarder was unable to fully exert its original braking force.

The present inventors conducted a current generated by changes in the magnetic lines of force generated in the magnetic material of the retarder unit due to the rotation of the flywheel during deceleration to a radiator whose resistance value can be variably controlled. By changing the rotation speed, the optimum braking force can be obtained for the rotation speed, and the retarder unit can be protected from overheating by heat dissipation from the resistor, and the present invention has been completed.

[Purpose of the invention]

When braking is applied by a retarder to decelerate a vehicle, the present invention guides the current generated in the retarder to a radiator whose resistance value can be variably controlled, thereby providing the optimum braking force according to the engine speed. In addition, the purpose is to protect the retarder unit from heating by heat dissipation from the resistor.

[Features of the invention]

The present invention relates to a shaft of a power transmission system connected to a vehicle engine;
In other words, it includes a magnetic rotor that is attached to the crankshaft, the input or output shaft of a transmission, a propeller shaft, etc., an excitation coil that applies magnetic force to this rotor, and a power generation coil that generates current by the rotation of this rotor. a plurality of retarder units for braking the vehicle; a retarder switch for intermittent excitation current flowing to the excitation coil due to dispersion of the vehicle; and a retarder switch connected to the generator coil to convert the current generated in the generator coil into heat. A variable resistor configured to convert and radiate heat; a rotation sensor that detects the rotational speed of the engine as an electrical signal; and a resistance value of the variable resistor is controlled in accordance with the output signal of the rotation sensor. It is characterized by being equipped with a control circuit to obtain braking according to the rotational speed of the engine, and to protect the retarder unit from heating.

[Explanation based on examples]

Next, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention.

In the device of this embodiment, a flywheel 4 having teeth 3, which are monomagnetic rotors, arranged around its outer periphery is attached to a crankshaft 2 of an engine 1. A retarder unit 6 is attached to the flywheel housing 5. A battery 7 that supplies excitation current is connected to the retarder unit 6 via a retarder switch 8 . Further, a heat radiator 10 whose resistance value can be variably controlled is connected to the power generation coil 9 wound around the core of the retarder unit 6.

FIG. 2 is an enlarged configuration diagram of the retarder unit 6 and flywheel 4 in FIG. 1. A large number of teeth 3 are formed around the outer periphery of the flywheel 4. The retarder unit 6 is formed by an excitation coil 11 for applying magnetic force to the teeth 3, and a power generating coil 9 that generates a current due to changes in magnetic lines of force generated between the core 12 and the teeth 3, which form a circuit of magnetic lines of force. - A plurality of retarder units 6 are attached to the flywheel housing 5.

A characteristic configuration of the present invention is that a rotation sensor 13 that detects the engine rotation speed is provided at the front end of the crankshaft 2 of the engine 1, and the output of this rotation sensor 13 is connected to a control circuit 14 that controls the resistance value of the radiator 10. It's right there. This control circuit 14 controls the slider 10a to increase the resistance value of the radiator 10 when the rotation sensor 13 detects a high rotation speed, and controls the slider 10a to increase the resistance value of the radiator 10 when the rotation sensor 13 detects a low rotation speed. The slider 10a is controlled so as to reduce the resistance value of 0.

The operation of the apparatus of this embodiment configured as described above will be explained next.

When the retarder switch 8 provided on the driver's seat of the vehicle is turned on, an excitation current flows from the battery 7 to the excitation coil 11.1. A magnetic circuit is formed between the magnetic lines of force and the teeth 3 of the flywheel 4, which is a magnetic rotor, and the core 12 and teeth 3 are attracted to each other, so a braking force is applied to the flywheel 4 that is about to rotate. arise.

On the other hand, since the teeth 3 cut the lines of magnetic force from the core 12 one after another by the rotation of the flywheel 4, an electromotive force is generated in the generator coil 9. This current flows to the heat sink 10 via the output line 15.

When the retarder is used for braking when the engine 1 rotates at high speed, the flywheel 4 cuts the lines of magnetic force at high speed, so the current generated in the generator coil 9 increases. At this time, since the output level of the rotation sensor 13 becomes high, the control circuit 14 controls the resistance value of the radiator IO to increase. As a result, the rotation of the flywheel 4 receives resistance and the braking force of the retarder increases. Conversely, when the engine 1 is rotating at a low speed, the control circuit 14 lowers the resistance value of the radiator 10 because the output level of the rotation sensor 13 becomes low. Thereby, sufficient braking force can be exerted when the engine 1 rotates at low speed.

In this way, by changing the load resistance using the variable resistor according to the rotational speed of the engine 1 so as to select conditions that provide good efficiency as a generator, an appropriate braking force can be obtained according to the running state of the vehicle.

Further, the generated current is converted into thermal energy by the variable resistor 10 and dissipated into the atmosphere, so that the retarder unit 1-6 does not overheat and can be prevented from burning out.

〔Effect of the invention〕

As described above, according to the present invention, the electric current generated during braking of the retarder directly connected to the shaft of the drive system connected to the engine is used to generate a heat sink according to the rotational speed of the engine using a radiator composed of a variable resistor. By connecting a load resistor,
An appropriate braking force can be obtained depending on the running condition of the vehicle, and the heat dissipation of the resistor has an excellent effect of preventing overheating of the retarder unit.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an apparatus according to an embodiment of the present invention. FIG. 2 is an enlarged configuration diagram of the retarder unit. l...engine, 2...crankshaft, 3...teeth, 4...flywheel (magnetic rotor), 6...
・Retarder unit, 7...Battery, 8...Retarder switch, 9...Generating coil, 10...Radiator, 11...Exciting coil, 12...Core, 13...
Rotation sensor, 14... control circuit. Patent Applicant Hino Motors Co., Ltd. Representative Patent Attorney Naotaka Ide

Claims (1)

[Claims] (1) Includes a magnetic rotor mounted on the shaft of a power transmission system connected to a vehicle engine, an excitation coil that applies magnetic force to this rotor, and a power generation coil that generates a current by the rotation of this rotor, and the above-mentioned a plurality of retarder units for braking the vehicle; a retarder switch for intermittent excitation current flowing from the battery of the vehicle to the excitation coil; and a retarder switch connected to the generator coil to convert the current generated in the generator coil into heat. a variable resistor configured to convert and radiate heat; a rotation sensor that detects the rotational speed of the engine as an electrical signal; and a control that controls the resistance value of the variable resistor in accordance with the output signal of the rotation sensor. A vehicle retarder braking force control device comprising a circuit.