JPS58187515A - Water pump of internal-combustion engine - Google Patents

Abstract

PURPOSE:To improve the fuel-air ratio and cooling efficiency of an engine by a method wherein the driving operation of the water pump of the titled device is changed-over to the electric motor driving via a jointing means or to the engine driving via a belt-pulley. CONSTITUTION:A rotating shaft 6 of an electric motor 5 as the first driving means is engaged and connectingly supported, via a bearing 7, to a boss hole 4A which is formed on the protruded end surface of a pump shaft 4 of a water pump 2 equipped to a cylinder block 1. A belt-pulley 8 as the second driving means is releasably supported, via a bearing 9, on an outer periphery of said pump shaft 4, also a magnetic clutch 10 is engaged into said pump shaft 4. Said magnetic clutch 10 magnetizes an armature 14A and makes it attract to a rotor 11, during an electromagnet 15A is electrified. Further, said magnetic clutch 10 joints said pump shaft 4 with said motor rotating shaft 6 via a retaining plate 12. Also said magnetic clutch 10 joints said belt-pulley 8 with said pump shaft 4 via said retaining plate 12 by the magnetizing and attraction of an armature 14B during an electromagnet 15B is electrified.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water pump for an internal combustion engine, and in particular to improvements to its drive device.Generally, in internal combustion engines for automobiles, most of the cooling of the engine is forcedly circulated by the water pump. The system employs a water cooling system that utilizes a cooling liquid (hereinafter referred to as cooling water).

The water pump is driven to rotate in direct conjunction with the rotation of the engine by a belt that is passed between the water pump date fixed to the pump shaft and the crank pulley of the engine. In other words, regardless of the operating state of the engine, the water pump is activated as soon as the engine is started.8 Therefore, when starting the engine, there is no need to drive the water pump to cool the engine. At low temperatures, the driving power of the water pump becomes power loss for the engine, and at cold temperatures it takes longer to warm up the engine, which is an important factor in reducing fuel consumption. was.

Therefore, this invention was developed based on an electromagnetic clutch used in a car cooler compressor that is similarly driven in conjunction with an engine (this electromagnetic clutch was disclosed in Japanese Patent Laid-Open No. 55-63).
The above problem can be solved by focusing on a joint means for auxiliary equipment such as No. 013) and configuring the water pump so that it can be selectively driven by an electric motor and a belt pulley via the joint means. The purpose is to solve the problem.

To this end, the present invention specifically includes a first driving means for rotationally driving the pump shaft by an electric motor on the water pump pump 1, and a first driving means for rotationally driving the pump shaft by an electric motor, and a belt drive unit for rotationally driving the pump 111 in conjunction with the engine. a second driving means;
A connecting means for selectively connecting both of these means to the pump shaft is provided, and the coupling means and the electric motor are connected to each other according to the operating condition of the engine. % on the operating side f...J:, jj It is configured to reduce the amount of work required.

Hereinafter, an example of this invention will be explained based on one page.

In FIGS. 1 and 2(A), reference numeral 1 indicates a cylinder block, and a water pump 2 is mounted on the front wall of the cylinder block 1. In FIG. Reference numeral 3 designates the pump housing, and 4 designates a pump shaft rotatably supported by the pump housing 3. A fitting hole 4A is formed in the end surface of the externally protruding end of the pump IllI4, into which the fitting hole 4A is formed. The mating hole 4 As a drive means for the AKml, a single rotation shaft 6 of an electric motor 5 is fitted and supported through a bearing 7 so as to be freely rotatable.

On the other hand, a belt pulley 8 serving as a second driving means is fitted and supported via a bearing 9 on the outer periphery of the externally protruding end of the pump shaft 4 so as to be freely rotatable. Of course, this belt pulley 8
A V-belt that transmits rotational force from a crank pulley (not shown) is wound around the belt.

The Ponzo shaft 47 is further provided with an electromagnetic clutch 1 as a coupling means for selectively connecting the first and second drive means 5.8 to the pump shaft 4 (that is, causing them to rotate integrally).
0 is set.

This electromagnetic clutch 10 includes a retaining plate 12, which is located between a rotor 11 fixedly attached to a rotating shaft 6 of an electric motor 5 and a belt pulley 8, and is fixedly attached to the outer periphery of a pump shaft 4. A pair of ring-shaped armatures 14A, 14B are attached concentrically to the pump shaft 4 via leaf springs 13 on both sides of the plate 12, and these armatures 14A, 14B are connected to the rotor 1'l and the belt pulley 8. Ring-shaped first and second electromagnets 15A are arranged on the side walls of the pump housing 3 and the electric motor 5 concentrically with respect to the respective shaft portions 4.6 so as to sandwich and correspond to each other.

15B.

Therefore, if the first electromagnet 15A is now moved to a position, the rotor 11. (formed in advance from a ferromagnetic material), a magnetic pole is formed between the corresponding armature 1
4A is magnetized and attracted to the rotor 11. As a result, the rotating shaft 6 of the electric motor 5 and the pump shaft 4 are integrated via the holding plate 12, and the water pump 2 can be driven by the electric motor 5. Become.

On the other hand, when the second electromagnet 15B is energized, a magnetic pole is formed between it and the belt pulley 8 (previously made of a ferromagnetic material), so the corresponding armature 14
B is magnetized and attracted to the belt pulley 8. As a result, the belt pulley 8 and pump shaft 4 are integrated via the holding plate 12, and the water bonder 2 is driven in conjunction with the engine. A control circuit 20 serving as a control means for switching and controlling the second drive means according to the engine operating state is configured as shown in the block diagram of FIG.

21 in the figure is a water temperature sensor that detects the engine cooling water temperature.
The detection signal of this water temperature sensor 21 is input to two comparators 22 and 23 of the control circuit 20. One of the comparators 22 is @
If the water temperature T is 1M compared to the reference temperature Tl of 1
7. Output a high level signal when the time exceeds t. The other comparator 23 compares the water iT with the second reference temperature T2.
When the degree TzTh is exceeded, a high level signal is output.

Similarly, reference numeral 24 in the figure is a rotation sensor that detects the engine rotation speed, and a detection signal from this rotation sensor 24 is input to a comparator 25 of the control circuit 20. This comparator 25 compares the rotational speed Re with a predetermined reference rotational speed fRm and outputs a high level signal when the rotational speed Re exceeds the speed Rm.

The respective output signals of the comparators 22, 23 and 25 are input to the logic operation circuit 26, and the result of the operation processing here is the first
and is output as an activation signal for the second switch circuits 27 and 28.

The first switch circuit 27 is connected to control the operation of the electric motor 5 and the first electromagnet 15A, and the second switch circuit 28 is connected to control the operation of the second electromagnet 15B. .

On the other hand, in the above N++ logical operation circuit, the output of the comparator 22 described above is input to the -1 ANL) circuit 29, and the output of this AND circuit 29 is input to the OR circuit 3 (via 1-) of the first switch. It is input to the circuit 27.

The output of the comparator 23 is input to the tenth) AI'JI) circuit 29 through the NOT circuit 31, and is also input to the second and third ANI) circuits 32 and 33. The output of the comparator 25 is further input to the second AND circuit 32, and the output of this AND circuit 32 is input to the second switch circuit 28, and is also input to the third AND circuit 33 via the NOT circuit 34. be done.

Then, the output of this third AND circuit 33 is the above-mentioned O
It is input to the R circuit 30.

Therefore, the first AND circuit 29 has an output signal from the comparator 22 when the water @T exceeds the first reference temperature T1, but an output signal from the comparator 23 when the water @T exceeds the second reference temperature T2. It outputs a high level signal only when there is no
The circuit 32 goes high only when the water temperature T exceeds the second reference temperature Tzt- and there is an output signal from the comparator 23, and furthermore, when the rotational speed Re exceeds the reference speed Rm1 and there is an output signal from the comparator 25. give a signal. Furthermore, the third AND circuit 33 has water @T as the second reference temperature! Although there is an output signal from the comparator 23 exceeding fTz', as mentioned above, a high level signal is output only when the rotational speed Re is below the reference speed lfam and there is no output signal to the second AND circuit 32. .

Further, the OR circuit 30 outputs a high level signal when there is an output signal from the first AND circuit 29 or when there is an output signal from the third AND circuit 33.

Next, the operation of this embodiment configured as described above will be explained with reference to FIGS. 4 and 5.

When the cooling water temperature T is low, such as when the first reference temperature Tl of the comparator 22 is low, such as during side start operation or low temperature, the comparators 22 and 23 do not output signals, so the engine rotation speed kLe
No matter what state the switch circuits 27 and 28 are in, no activation signal is output from the first and second switch circuits 27 and 28.

As a result, the electric motor 5, the first electromagnet 15A, and the second electromagnet 15B&';J do not operate, only the belt belt 8 idles, and the water pump 2 does not operate.As a result, the water pump 2 is driven. During this operation, when there is no need to cool the engine, there is no power loss required to drive the engine pump, and fuel efficiency is further improved.

Then, during warm-up operation, etc., the cooling water temperature T changes to the comparator 2.
When the temperature reaches an intermediate point between the first reference temperature l111 of No. 2 and the second reference knitting T2 of the comparator 23, that is, Tl(T≦
At T2, the comparator 22 outputs the full output signal, while the comparator 23 does not output any output signal. Therefore, as described above, the first switch is output via the first AND circuit 29 regardless of the engine speed Re. Only circuit 27 outputs an activation signal.

As a result, the electric motor 5 and the first electromagnet 15
A is actuated, and this causes the rotating shaft 6 of the electric motor 5 to rotate as described above. Since the water pump shaft 4 is integrated with the pump shaft 4 through the entire holding plate 12, the water pump 2 is driven at a constant speed by the electric motor 5 (see Fig. 5). Since power loss is reduced and overcooling of the engine is avoided, fuel efficiency is improved and warm-up time is shortened - the cooling water temperature T rises further and exceeds the second reference temperature T2 of the comparator 23. (that is, when T+<Tm<T), when the rotational speed Re is smaller than the reference speed Km of the comparator 25, the comparator 23 outputs an output signal, while the comparator 2
Since 5 does not output an output signal, the water pump 2 is connected to the first switch via the third AND circuit 33 as described above. As a result, when the engine is at a high temperature and the engine is rotating at a low speed, two water pumps are driven by the electric motor 5 whose rotational speed is set earlier than that. It is possible to improve the cooling efficiency and completely prevent the engine from overheating. On the other hand, in the case described above, when the rotational speed Re also exceeds the reference speed IfRm' of the comparator 24, both the comparators 23 and 25 output an output signal. the second AND
Via the circuit 32, only the second switch circuit 28 now outputs an activation signal.

In response to this, the second electromagnet 15B is operated in place of the electric motor 5 and the second electromagnet 15A.
+ Since the belt pulley 8 and the pump shaft 4 are integrated via the holding plate 12, the water pump f2 is driven in conjunction with the engine.

As a result, when the engine is at a high temperature and rotates at high speed, the pump speed can be increased in proportion to the engine rotational speed (see FIG. 5), as in the conventional example, and overheating of the engine can be completely prevented.

In this way, the water pump 2 is effectively controlled in accordance with the cooling water temperature and rotational speed of the engine.As explained above, according to the present invention, the electric motor is Since it is possible to selectively drive the water pump in accordance with the operating condition of the entire engine, the fuel efficiency and cooling performance of the engine can be further improved.

[Brief explanation of drawings]

Figure 1 is a sectional view of the main part of an embodiment of this invention, Figure 2 (8)
, Figure 3 is a block diagram of its control circuit, Figure 4 is a table showing the control mode Pi of its operating section, and Figure 5 is its driving diagram. (Operation of the device) 4-pin diagram, 4...Bonde shaft, 5
. . . Electric motor, 8. Belt glue, 10. Electromagnetic clutch, 2o. Control circuit, 21. Water temperature sensor, 24. 101 rotation sensor, 2. Water pump. Patent applicant Nissan Motor Co., Ltd.

Claims (1)

[Claims] 1. A first drive means for rotationally driving the pump shaft by an electric motor, and a second drive means for rotationally driving the pump shaft in conjunction with the engine by a belt pulley, on the shaft. and a joint means for selectively connecting both of these means to the pump shaft, and a control means for controlling the operation of the joint means and the electric motor according to the operating state of the engine. Engine water pump. 2. The coupling means includes a pair of armatures fixed to the pump shaft side, a belt pulley rotatably supported by the pump shaft with the armatures sandwiched between them, and a rotor portion of the electric motor. The first
2. The water pump for an internal combustion engine according to claim 1, which is a magnetic clutch comprising a first electromagnet and a second electromagnet. 3. The control means inputs a signal from a sensor that detects the engine cooling water temperature and rotation speed, and when the cooling water temperature is below the first reference temperature, the water pump is completely stopped regardless of the rotation speed. When the temperature exceeds the first reference temperature and is below the second reference temperature, the electric motor operates the water pump regardless of the rotation speed, and even if the temperature exceeds the second reference temperature, the water pump continues to operate. When the speed is below the reference speed, the electric motor is used to operate the water pump, while when the rotational speed is below the reference temperature, a signal is sent to the belt pulley to operate the water pump. A water pump for an internal combustion engine according to claim 1 or 2, which is a control circuit that outputs an output.