JPS6131141Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a water pump control device for an engine.

Generally, in an engine, a water jacket is provided on the cylinder block and the cylinder head, and cooling water is circulated within the water jacket by driving a water pump to cool each part.

In the above-mentioned water pump, the rotation of the crankshaft of the engine is normally transmitted through a belt through a pulley, and the water pump is constantly driven to rotate while the engine is rotating to circulate cooling water. (For example, see Utility Model Application No. 53-47408.) Therefore, when starting the engine, that is, cranking, the water pump is rotated via the engine crankshaft by the driving force of the starter motor, which improves starting performance. This is becoming an obstacle to improvement.

In other words, the higher the cranking rotation speed, the better the engine startability, but driving the water pump becomes a load on the starter motor, lowering the cranking rotation speed, and inhibiting engine startability. At the same time, it is necessary to increase the capacity of the starter motor and battery.

In view of these points, the present invention has been devised to provide a water pump that can drive and control the water pump independently of the engine rotation, and also detects the starting state of the engine and stops the operation of the water pump when the engine starts. It is an object of the present invention to provide a pump control device to overcome the drawbacks of the prior art.

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is an engine, 2 is a cooling water passage provided with a radiator 3, and the cooling water passage 2 is connected to a water jacket formed in a cylinder block 4 of the engine 1 from downstream of the radiator 3, and It passes through a water jacket formed in the cylinder head 5 and is configured to communicate with the upstream side of the radiator 3 via a thermostat 6.

A water pump 7 for feeding cooling water is interposed in the cooling water passage 2, and the water pump 7 is configured to be able to be driven and controlled independently of engine rotation by a drive device 8, and this drive device 8
is controlled in conjunction with the control device 9, and the rotation speed of the water pump 7 is controlled.

That is, the water pump 7 is connected to an electric motor 11 via a transmission belt 10, and the operation of the electric motor 11 is controlled by signals from a control device 9.

Further, 12 is a temperature sensor that detects the engine temperature, and the output of the temperature sensor 12 is input to the control device 9, and the control device 9 receives the output of the temperature sensor 12 and controls the drive device 8. When the engine temperature is low, the rotation speed of the water pump 7 is reduced or stopped, and when the engine temperature rises, the water pump 7 is
The rotation speed of the engine is increased or the drive is started.

In the illustrated case, the temperature sensor 12 is mounted on the cylinder head 5 of the engine 1 and is configured to detect the engine temperature from the cooling water temperature or wall temperature of the high temperature portion.

On the other hand, reference numeral 13 denotes a starting sensor that detects the starting state of the engine 1. The output of the starting sensor 13 is also input to the control device 9, and the control device 9 receives the output of the starting sensor 13 and controls the drive device 8. When the engine 1 is in the starting operation state, the operation of the water pump 7 is stopped.

As the starting sensor 13, a known sensor that detects the starting state (cranking state) of the engine 1 can be used, such as one that detects from the start of the starter motor, or one that detects from the operation of the starter switch (ignition key switch). What is detected is used as appropriate.

Furthermore, 14 is a heating device (radiator) branch-connected to a part of the cooling water passage 2, and the amount of cooling water supplied from the cooling water passage 2 to the heating device 14 is adjusted by an on-off valve 15. In addition, 16 is a heating device 14
It is a ventilation fan.

FIG. 2 shows an example of the control device 9, in which the output signal of the temperature sensor 12 is input to a temperature detection circuit 17 to detect the engine temperature, and the output signal of the temperature detection circuit 17 is used to calculate the output current. The signal is input to the circuit 18. This output current calculation circuit 18
calculates an output current to drive the electric motor 11 at a predetermined rotation speed in accordance with the magnitude of the engine temperature signal from the temperature detection circuit 17, and outputs it to the drive device 8 via the current control circuit 19. . The output signal of the starting sensor 13 is input to the current control circuit 19, and when the engine 1 is in the starting state, the output signal from the current control circuit 19 to the drive device 8 is cut off.

The output current from the current control circuit 19 is applied to a relay 20 that starts and stops the electric motor 11, and is also applied to the base of a transistor 22 connected to a rotation control coil 21 of the electric motor 11. That is, when the output current becomes larger than a predetermined value, the contacts of the relay 20 are closed to start the electric motor 11, while a rotation control current corresponding to the output current flows to the rotation control coil 21 due to the action of the transistor 22, and the electric motor is activated. It is configured to control the rotation speed of the motor 11, that is, the rotation speed of the water pump 7, to a predetermined rotation speed.

In the above embodiment, the rotation speed of the water pump 7 is basically controlled according to the engine temperature, so the operation of the water pump 7 is stopped when the engine temperature is below the set temperature. In the case where the water pump 7 is configured to do so, the operation of the water pump 7 may be stopped regardless of the detection by the starting sensor 13.

Also, depending on the engine temperature, the water pump 7
The present invention is also applicable to devices that are not configured to perform rotation control.

Furthermore, although the above embodiment has been described with one system of cooling water passages 2, this cooling water passage is divided into a first cooling water passage that cools the high temperature section (cylinder head 5) of the engine 1 and a low temperature section (the cylinder head 5) of the engine 1. It is also applicable to a configuration in which the system is branched into two systems including a second cooling water passage for cooling the cylinder block 4).

Further, in the above embodiment, an example was shown in which the electric motor 11 was used as the drive device 8 of the water pump 7, but the present invention is not limited to this. For example, the water pump is connected to the output shaft of the engine. The driving device may be configured to drive in conjunction with each other via a variable pulley mechanism, and may be configured to control the gear ratio of this variable pulley mechanism.Furthermore, the water pump may be connected to the output shaft of the engine via a clutch mechanism. It is also possible to use a driving device that drives in conjunction with each other.

Therefore, according to the present invention as described above, the water pump can be driven and controlled independently of the engine rotation, and the operation of the water pump is stopped when the engine is started. By reducing the load on the starter motor, it is possible to improve starting performance and downsize the starter motor and battery.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the present invention, with FIG. 1 being an explanatory diagram showing the overall configuration, and FIG. 2 being a control circuit diagram showing an example of a control system. DESCRIPTION OF SYMBOLS 1... Engine, 2... Cooling water passage, 3... Radiator, 6... Thermostat, 7... Water pump, 8... Drive device, 9... Control device, 1
1...Electric motor, 12...Temperature sensor, 13
...Start sensor.

Claims (1)

[Scope of utility model registration request] A water pump that feeds cooling water into the engine, a drive device that can drive and control the water pump independently with respect to engine rotation, a starting sensor that detects the starting state of the engine, and a starting sensor that detects the starting state of the engine. 1. A water pump control device for an engine, comprising: a control device for stopping operation of the water pump when a receiving engine is started.