JP2588592Y2 - Engine cooling system on engine dynamo - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a device for cooling an engine on an engine dynamo (hereinafter simply referred to as an engine cooling device).

[0002]

2. Description of the Related Art Conventionally, engines such as automobiles are subjected to performance tests such as rotation characteristics using an engine dynamo. However, heat is generated as the engine rotates and a temperature rise occurs. Conventionally, a tank containing cooling water and the engine are connected by two pipes, and the engine is cooled by the cooling water.

FIG. 2 schematically shows the structure of a conventional engine cooling apparatus. In this figure, reference numeral 1 denotes an engine mounted on an engine dynamo table and mechanically coupled to the engine dynamo 2, for example, an engine of an automobile. It is. 3 is cooling water 4
And is connected to the engine 1 by two pipes 5 and 6. Cooling water 4 is supplied from the tank 3 to the engine 1 through a pipe 5 (hereinafter, referred to as a first pipe), and the cooling water 4 after cooling the engine 1
Is connected to the tank 3 via a pipe 6 (hereinafter, referred to as a second pipe).
Return to

The tank 3 has a control valve 7 such as a solenoid valve.
And a drain pipe 9 for discharging the overflowing cooling water 4. Also, the second
The pipe 6 is provided with a temperature sensor 10 for detecting the temperature of the cooling water 4 after cooling the engine 1. Reference numeral 11 denotes a temperature controller, which is configured to output an on / off control signal b based on a PID constant to the control valve 7 based on a detection output a from the temperature sensor 10. I have.

In the above conventional engine cooling device,
The engine 1 is cooled by a cooling water 4 supplied from a tank 3 via a first pipe 5 by a pump (not shown) provided in the engine 1, for example. Then, the cooling water 4 after cooling the engine 1 returns to the tank 3 via the second pipe 6.

[0006] The temperature of the cooling water 4 after cooling the engine 1 is detected by a temperature sensor 10 provided in the second pipe 6, and the detected output a is input to a temperature controller 11. When the detection result is higher than the predetermined temperature, an ON / OFF control signal b based on the PID constant is issued from the temperature controller 11 to the control valve 7 interposed in the cooling water supply pipe 8, whereby The control valve 7 opens and closes appropriately, and the cooling water 4 is supplied to the tank 3.

[0007]

However, in the above-mentioned conventional engine cooling device, the temperature controller 11 is adapted to almost the entire temperature range of the engine 1 and adapted to the case where the temperature changes gradually. So only one PID
If only constants are set and, for example, the number of revolutions of the engine 1 changes greatly and the amount of heat generated changes greatly, the duration of overshoot or undershoot increases, and the time corresponding to the temperature of the engine 1 increases. And engine 1
It is difficult to perform cooling with high precision and responsiveness.

For this reason, when the engine 1 suddenly changes from a full load state in which the number of revolutions is, for example, 4,000 times per minute to an idling state in which the number of revolutions is several hundred times per minute, the performance test is performed. There is variation in the data, the accuracy in the transient state is poor, and one PI
In order to cover all states with D, it took time to reach a steady state.

The present invention has been made in consideration of the above-mentioned matters, and an object of the present invention is to provide an engine capable of following a change in the number of revolutions of the engine and rapidly performing a corresponding cooling. It is to provide a cooling device.

[0010]

In order to achieve the above object, in the present invention, a tank containing cooling water and an engine are connected by two pipes, and the engine is cooled with the cooling water and the engine is cooled. The temperature of the cooling water discharged from the tank is detected, and the supply amount of the cooling water to the tank is determined by PI
A plurality of PID constants corresponding to the engine speed are provided in the engine cooling device on the engine dynamo that is controlled by the D control, and an optimum PID constant is selected based on the detected engine speed. The control valve for cooling water supply is controlled to open and close based on the selected PID constant.

[0011]

A plurality of PID constants can be selected, an optimum PID constant can be selected based on the detected engine speed, and the cooling water supply control valve can be opened and closed based on the PID constant. The engine can be cooled accurately and quickly.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing an example of an engine cooling device according to the present invention. In this figure, reference numeral 12 denotes a rotation detection sensor for detecting the number of revolutions of the engine 1, and a detection output c of the rotation detection sensor is sent to a contact output board 13 described later. Is entered. Reference numeral 13 denotes a board that outputs a contact corresponding to the rotation speed of the engine 1.
Reference numeral 14 denotes a temperature controller having a PID constant switching function, and has a plurality of (six in the illustrated example) PID constants. As these PID constants, those that can change the response speed, the stability, and the like by setting the coefficients in various ways are prepared. And this temperature controller 14
While the detection output a from the temperature sensor 10 is input,
When the output d of the contact output board 13 is input, the output is switched to the preset optimum PID constant. FIG.
2, the same reference numerals as those shown in FIG. 2 indicate the same items.

Next, the operation of the engine cooling device having the above configuration will be described. The cooling water 4 in the tank 3 is supplied to the engine 1 through the first pipe 5, and the engine 1 is rotated while cooling the cooling water. At that time, the temperature of the cooling water 4 returning from the engine 1 to the tank 3 is detected by a temperature sensor 10 provided in the second pipe 6, and the detected output a is input to the temperature controller 14. On the other hand, the rotation speed of the engine 1 is detected by the rotation detection sensor 12, and the detection output c is input to the contact output board 13.

A set of PID constants most suitable for the rotation speed of the engine 1 is selected from the contact output board 13 on the basis of the detection output c, and this is set as an output signal d as a temperature controller 14.
Sent to In the temperature controller 14, when the temperature of the cooling water 4 from the engine 1 side to the tank 3 side detected by the temperature sensor 10 is higher than a set value, the control signal b based on the selected PID constant is output. It is sent to the control valve 7 to control its opening and closing. Thereby, the cooling water 4 is newly supplied to the tank 3, and the cooling water 4 is supplied to the first pipe 5.
The engine 1 is supplied to the engine 1 through a predetermined cooling.

[0015]

[Effects of the Invention] As described above, according to the present invention,
When the temperature of the engine rises, it detects this quickly and selects the best PID constant for the engine speed,
Since the cooling water is supplied to the tank containing the cooling water for cooling the engine, the cooling of the engine can be performed without waste.

In particular, according to the present invention, the control accuracy can be improved by a factor of three in comparison with the prior art, in response to a large change in the engine speed from the full load state of the engine to the idling state.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating a configuration example of an engine cooling device according to the present invention.

FIG. 2 is a diagram schematically showing a configuration example of a conventional engine cooling device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 3 ... Tank, 4 ... Cooling water, 5, 6 ... Piping, 7 ... Control valve.

Continuation of the front page (56) References JP-A-4-43812 (JP, A) JP-A-62-2147 (JP, A) JP-A-3-17134 (JP, U) JP-A-56-135143 (JP (U, U) Real opening 63-111643 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F01P 3/20 G01M 15/00 F01P 11/00

Claims (1)

(57) [Scope of request for utility model registration] 1. A tank containing cooling water and an engine are connected by two pipes, the engine is cooled with the cooling water, and the temperature of the cooling water discharged from the engine side is detected, and the temperature of the tank is controlled. In an engine cooling device on an engine dynamo in which the supply amount of cooling water is controlled by PID, a plurality of PIDs corresponding to the number of rotations of the engine are provided.
A constant is provided, an optimal PID constant is selected based on the detected engine speed, and a control valve for cooling water supply is opened and closed based on the selected PID constant. Engine cooling system on the engine dynamo.