JPH0417715A - Cooling device of internal combustion engine - Google Patents

Abstract

PURPOSE:To improve the loading performance while avoiding the increase in the resistance of water flowing by controlling the flow path area of heat exchanged fluid in a pump block to increase when the fluid pressingly sending means provided to a sub-fluid pump is not operated. CONSTITUTION:In the case where an engine 2 is sufficiently cooled due to the circulation of cooling water based on a main water pump 4, the sub-water pump 7 installed in the path on the cooling water introduction side of a cooling water main circuit 3 is stopped. A cooling water path having a water flow area permitting the flow of free cooling water is formed between a variable housing 16 and stationary rotor 13. Since owing to this constitution, even if the sub-water pump 7 is stopped, the pressure to flow water is not lost, the sufficient circulation flow quantity of cooling water based on the drive of the main water pump 4 is secured resulting in the proper cooling of the engine 2. In addition, since a by-path making a detour around the sub-water pump 7 is not necessary, the loadage of a vehicle can be improved.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a cooling device for cooling equipment to be cooled, such as an internal combustion engine of a vehicle.

[Prior Art] In order to efficiently cool cooled equipment such as internal combustion engines, it is effective to increase the flow rate of cooling water. It is installed in the cooling water circulation path.

However, if you simply install a subwater pump, the subwater pump acts as a resistance to the cooling water passing through the circulation path, and the cooling water pumped by the main pump (main fluid pump) that operates as the internal combustion engine rotates. This may result in a decrease in the flow rate of the engine, and equipment to be cooled such as an internal combustion engine may not be sufficiently cooled.

Therefore, as shown in FIG. 17, when the 1st subwater pump 3J is installed in the cooling water circulation path together with the main water pump 4J, a pump bypass path 5J is provided to bypass this subwater pump 3J. It has been proposed to provide a control valve 6J such as a check valve in the bypass path 5J (Japanese Utility Model Publication No. 190520/1983). In addition, in the figure, 1 is the radiator, 2 is the engine, and 7
J is a so-called thermostatic valve that switches the flow path depending on the temperature of the cooling water.

By flowing the cooling water through this pump bypass path 5J, it is possible to prevent a decrease in the flow rate of the cooling water when the subwater pump 3J becomes water flow resistance.

[Problems to be Solved by the Invention] However, the following problems have been pointed out in conventional sub-fluid pumps (sub-water pumps).

In recent years, as vehicles have become sportier, smaller and lighter,
Since the space in the engine room is limited, it is difficult to install the subwater pump 3J, which requires piping for the pump bypass path 5J as described above, in the engine room. Specifically, due to the convenience of installing piping in a narrow space, its assembly will reduce the efficiency of work and maintenance inspection work.

The present invention has been made in order to solve the above-mentioned problems.The present invention has been made to solve the above-mentioned problems. The purpose is to improve the ease of mounting on vehicles etc.

■ Two configurations [Means for solving the problem] Means adopted by the present invention to achieve the above object (as the basic schematic configuration is illustrated in the block diagram in Figure 1, the equipment to be cooled is a heat exchange fluid circulation path cp formed between a heat exchanger RG that cools the heat exchange fluid that cools the CB by exchanging heat with air and the cooled device CB;
a main fluid pump MP installed in the heat exchange fluid circulation path CP and forcibly constantly circulating the heat exchange fluid; and a main fluid pump MP that assists the main fluid pump MP and circulates the heat exchange fluid. A cooling device for an internal combustion engine including a sub-fluid pump SP, which is driven independently of the main fluid pump MP and drives the sub-fluid pump SP; a pump section PE between the pump section PE, which is provided in the sub-fluid pump SP and rotates by the drive means M1 to force-feed the heat exchange fluid; a flow path area changing means M3 for changing the flow path area; and a control means for driving and controlling the flow path area changing means M3 to increase the flow path area. The gist is that it is equipped with M4.

[Operation] The cooling device for an internal combustion engine having the above configuration includes a heat exchanger RG.
The heat exchange fluid circulation path CP formed between the heat exchange fluid and the cooled equipment CB is equipped with a main fluid pump MP and a auxiliary fluid pump SP, and the heat exchange fluid is pumped and the cooled equipment is pumped as follows. Cools the CB, etc.

The drive means M1 is driven independently of the main fluid pump MP to rotate the fluid pressure feeding means M2 of the auxiliary fluid pump SP, thereby forcing the fluid to be heat exchanged from the suction side to the discharge side via the pump section PE.

When the fluid pumping means M2 is not activated, the control means M4 is activated to control the flow path area changing means M3 for changing the flow path area of the fluid to be heat exchanged in the pump section PE to the side where the flow path area increases. do.

As a result, when the fluid pressure feeding means M2 is not in operation, based on the increase in the flow path area of the heat exchange fluid in the pump section PE compared to 1, the passage resistance of the heat exchange fluid in the pump section PE is reduced, and the pump is pumped from the suction side. The flow rate of the fluid to be heat exchanged passing through the partition PE to the discharge side is increased. This increase in flow rate 1. t,
Since this is done in the pump compartment PE, there is no need for a separate detour from the secondary fluid pump SP.

[Example] Next, an example in which the auxiliary fluid pump of the present invention is used in a cooling system for an internal combustion engine of a vehicle will be described based on the drawings.

Figure 2 is a schematic configuration diagram of the cooling system of the first embodiment;
The figure is a partially cutaway side view showing a sub-fluid pump, ie, a sub-water pump, incorporated in the cooling system.

As shown in Fig. 2, 1: This cooling system (a system that circulates cooling water between the radiator 1, which cools the surface cooling water by exchanging heat with air, and the engine 2; the radiator)
Driven by the engine 2, the cooling water main circuit 3 disposed between the engine 2 and the cooling water main circuit 3 has a recirculation side path.
It is equipped with a main water pump 4 that forcibly circulates cooling water all the time, and when the temperature of the cooling water flowing into the connection part of the bypass circuit 5 that connects the introduction side path and the return side path of the main circuit 3 is lower than the set temperature. is equipped with a bypass control valve 6 that opens the bypass circuit 5 and closes the main circuit 3, and closes the bypass circuit 5 and opens the main circuit 3 when the temperature exceeds a set temperature. In addition, a water temperature sensor 2a that detects the cooling water temperature immediately after the bath from the engine 2,
A rotation speed sensor 2b that detects the rotation speed of the vehicle, a vehicle speed sensor 8 that detects the speed of the vehicle, and are connected to each of these sensors and input their signals, and drive a motor 7a for driving the subwater pump according to the input signal. Electronic control circuit (E
CLJ) 10.

Therefore, when the coolant temperature is low, such as immediately after starting the engine, the coolant pumped out by the main water pump 4 circulates through the circuit 35 shown by the diagonal arrow in the figure, whose path is the bypass circuit 5. When the engine 2 generates heat and the cooling water temperature rises above the set temperature due to an increase in engine load, etc., the bypass circuit 5 is closed by the bypass control valve 6 and the main circuit 3 is opened, and then the circuit 36 shown by the white arrow in the figure is formed and the high temperature cooling water is transferred to radiator 1.
The air is cooled by outside air cooling wind (vehicle speed wind or cooling wind from an electric fan (not shown), etc.), reaches the engine 2, and circulates through the main circuit 3.

Next, the subwater pump 7 used in this embodiment will be explained.

As shown in FIG. 3, the subwater pump 7 is equipped with a rotatable rotor 13 between the suction port 1 and the discharge port 2, and a built-in motor 15 rotates the rotor 13 to control the inflow of cooling water. The cooling water flowing in from the suction port is sent from the discharge port 8012.

As shown in the figure, a variable housing 6 formed of a shape memory alloy is rotatably supported at one end by a shaft support 77 in a suction side housing 4 located opposite to the rotor 13. Connect the protrusion 18 on the other end to the suction side housing 1
It is assembled by being engaged with the engaging portion 14a of No. 4.

Note that this variable housing is formed so that even when the shape changes as will be described later, the end of the protrusion 18 on the forming side always remains in the engagement part 14a and operates in the engagement part 14a.

Furthermore, as shown in FIG. 4 when the subwater pump 7 is viewed from the direction of arrow A in FIG. , each variable housing 16 has a cooling water passage hole 16c.
is perforated.

Each variable housing 161 and the pivot support 17. The above ECtJ 1 using the engaging portion 14a as an electrical contact
0, and its shape changes as follows under power supply control by ECU 0.

That is, in order to maintain the optimum tip clearance (approximately 1 to 3 nvn) 19 between the tip and the rotor 13 when the power is not energized, and to exert the pumping ability by the rotation of the rotor 3,
The shape shown by A is maintained. - During the energization period 1. t
, maintains the shape shown by 16B in the figure by generating heat and increasing the temperature, and forms a cooling water passage between the rotor 13 and the rotor 13 that allows free passage of cooling water, thereby reducing water flow pressure loss at that time. In this way, the shape change between the shapes 16A and 16B (as the cooling water passes through the passage hole 16c, the change is made smoothly without any resistance).

Next 1: A cooling routine for driving and controlling the subwater pump 7 to cool the engine 2 in the cooling system configured as described above will be explained based on the flowchart of FIG. 5.

The cooling routine shown in FIG. 5 (initial processing that is performed only when the power is turned on by the ignition key (not shown above), that is, it is repeatedly performed after clearing internal registers, etc., starts from the water temperature sensor 2a. The coolant temperature Tw is read (S100). Next, it is determined whether the read coolant temperature Tw is less than the reference coolant temperature To (5105), and when it is determined that Tw (To), a stop signal is sent to the motor 7a. At the same time, each variable housing 16 is energized through the electrical contacts of the shaft support 17 and the engaging portion 14a to cause the variable housing 16 to generate heat (SIIO).
, and changes its shape to the shape shown at 168 in FIG.

Then, this routine ends.

In this way, when the engine 2 is sufficiently cooled by the circulation of cooling water based on the main water pump 4 (Tw<
To), the subwater pump 7 is stopped, and a cooling water passage with a flow area that allows free passage of cooling water is formed between the subwater pump 7 and the stopped rotor 13, and the water flow at that time is Reduce pressure loss.

On the other hand, if the cooling water temperature Tw rises due to an increase in the load on the engine 2, etc., and it is determined in step 5105 that Tw≧To (Table 1), the engine rotation speed Ne is read from the rotation speed sensor 2b (S120). The engine rotation speed Ne is the reference rotation speed N.

5125), and if it is determined that Ne≧No (Table 5125), if it is determined that Ne≧No (Table 5125), the sub water pump 7 is not required, and the routine shifts to 5IIO to reduce water flow pressure loss when the subwater pump is stopped, and this routine is temporarily terminated.

Then, if Ne is determined as No in 5125, the vehicle speed Ve is read from the companion vehicle speed sensor 8 (S130), and it is determined whether or not the read vehicle speed Ve is equal to the reference vehicle speed Vo (
S 135). Here, if it is determined that Ve≧Vo (
Since there is sufficient vehicle speed, the cooling water in the radiator 1 is cooled by a large amount of outside air cooling air, and the cooling of the engine 2 is good. After reducing the loss, this routine is temporarily terminated.

On the other hand, if it is determined that Ve<Vo in step 5135 (S140), a drive signal is output to the motor 7a, the sub-water pump 7 pumps cooling water, and the power supply to each variable housing 16 is stopped (S140). The shape is 16 in Figure 3.
Return to the shape shown in A. In other words, the optimal tip clearance] 9 is secured between the rotor 13 and the variable housing 16, cooling and dynamic water is pumped through the rotation of the rotor 13, and the flow rate of cooling water circulating through the main circuit 3 is increased. end.

As explained above, 1: Due to the cooling system of the first embodiment, when the cooling water temperature Tw is low, the engine speed Ne is high, or the vehicle speed Ve is high, the sub water pump 7 is Even if the main water pump 4 is stopped, no pressure loss of the cooling water is caused in the main circuit 3, so that a sufficient circulating flow rate of the cooling water based on the drive of the main water pump 4 can be ensured, and the engine 2 can be suitably cooled.

Moreover, in order to reduce the water flow resistance in this way, there is no need for a bypass path ε that bypasses the subwater pump 7, so that the ease of mounting on a vehicle can be improved.

For example, when the first engine is forced to operate under high load and at low rotation speeds, such as when driving uphill, the subwater pump 7 is naturally driven to pump out cooling water and circulate it through the main circuit 3. Cooling water flow rate can be increased.

As a result, by cooling the engine 2 with the internal combustion engine cooling system using the subwater pump 7,
The engine 2 can be suitably cooled at all times even under various driving conditions.

Next, a second example will be described. Incidentally, in the description (the same configuration as the first embodiment described above), the description will be simplified.

FIG. 6 is a schematic configuration diagram of the cooling system of the second embodiment, FIG. 7(A) is a partially cutaway plan view of the subwater pump 20 used, FIG. ) is a partially cutaway front view and a partially cutaway side view.

As shown in FIG. 6, 1: This cooling system (similar to the first embodiment described above, coolant is circulated between the radiator 1 and the engine 2; The above-mentioned main water pump 4 is provided in the reflux side path of the cooling water main circuit 3 arranged in A control valve 6 is provided.

A subwater pump 20 is provided, which has a pump housing connected to the radiator head 1 and the radiator 2 housing.

Others 1: water temperature sensor 2a, rotation speed sensor 2b.

An electronic control circuit (EC) is equipped with a vehicle speed sensor 8, is connected to each of these sensors, inputs the signals, and controls the motor 20a for driving the subwater pump according to the input signals.
U) Equipped with 10.

Therefore, when the coolant temperature is low, such as immediately after starting the engine, the coolant pumped out by the main water pump 4 circulates through the circuit 35 shown by the diagonal arrow in the figure, whose path is the bypass circuit 5.On the other hand, When the engine 2 generates heat and the cooling water temperature rises above the set temperature due to an increase in engine load, etc., the bypass circuit 5 is closed by the bypass control valve 6 and the main circuit 3 is opened, and then the circuit 36 shown by the white arrow in the figure The high temperature cooling water is cooled in the radiator 1 by outside air cooling air (vehicle speed wind or cooling air from an electric fan (not shown), etc.), reaches the engine 2, and circulates through the main circuit 3.

Next 1: The subwater pump 20 used in this embodiment will be explained.

As shown in FIG. 7, an impeller 22 is placed inside a subwater pump 20 (resin pump housing 2 integrally molded with the housing of the radiator 2), and an impeller 22 is mounted on bearings 23a, 2.
The motor 20a for driving the subwater pump is provided on the outside of the pump housing 21 and is directly connected to the shaft of the impeller 22.

That is, the subwater pump 20 has a pump compartment 21 for pumping cooling water between the pump housing 21 and the upper surface of the radiator core 24 based on the rotation of the impeller 22.
It forms a. And, between the inside of the inlet pipe 25 communicating with the end of the introduction side path of the main circuit 3 and the pump compartment 21a (a switching valve 2 that opens and closes the friend passage hole 25a
6 is installed.

Further, the bearing 23a is assembled and fixed inside the end of the inlet pipe 25 to a hollow rib (not shown) that allows passage of cooling water. For this reason, the cooling water flowing from the inlet pipe 25 freely flows into the impeller 22 side along the outer periphery of the bearing 23a, as shown in FIG. do.

Note that a radiator cap 27 is provided on the suction side of the subwater pump 20 (to suppress cavitation at the front cooling water suction part and increase pumping capacity).

Next, a cooling routine for driving and controlling the subwater pump 20 to cool the engine 2ε in the cooling system configured as described above will be explained based on the flowchart of FIG. 10. In explaining this cooling routine, the same processing as the cooling routine explained in the first embodiment of Table 1 will be explained in a simplified manner.

As shown in FIG. 10, the cooling routine in the cooling system of the second embodiment (Table 1) Similar to the first embodiment, the cooling routine is repeatedly executed after a well-known initial process.First, the cooling water temperature Tw is read ( S200), and then it is determined whether the reference cooling water temperature is less than 10 (S205).

Here, if it is determined that Tw(To), then the motor 20a
8 outputs a stop signal to stop the impeller 22 (S210
), - then end this routine.

In this way, when the engine 2 is sufficiently cooled by the circulation of cooling water based on the main water pump 4 (Tw<
(T o) to stop the water pump 20.

In this case (cooling of the companion engine 2 is provided only by the circulation of cooling water based on the main water pump 4, but as shown in FIG. As soon as the water flows into the pump compartment 21a, the switching valve 26 is pushed open based on the pumping pressure from the main water pump 4, and the flow smoothly flows into the pump compartment 21a from the communication hole 25a without resistance. It flows into the core 24, where it exchanges heat with the outside air and is cooled.

In other words, the intread pipe 25 and the radiator core 24
A cooling water passage (communication hole 25a) having a flow path area that allows free passage of cooling water is formed between the pump compartment 21 and the pump compartment 21.
Reduce the pressure loss of cooling water passing through a.

On the other hand, when the cooling water temperature Tw rises and it is determined that Tw≧TO, the engine rotation speed Ne is read (S22
0), then it is determined whether or not the reference rotation speed is less than N0 (
S 225). If it is determined that Ne≧NO, the engine 2 can be cooled by ensuring a sufficient circulation flow rate of cooling water by the main water pump 4, so the process moves to 5210, stops the sub water pump 20, and temporarily ends this routine. do.

Then, when it is determined that Ne<No, the vehicle speed Ve is read (S230) and the magnitude of the reference vehicle speed Vo is determined (8).
235) in sequence. If it is determined that Ve≧Vo,
Since the vehicle speed is sufficient, the cooling water based on the large amount of outside air cooling air in the radiator and the cooling of the engine 2 are considered to be good, so the process moves to 5210, stops the subwater pump 20, and executes this routine. finish.

On the other hand, if it is determined in 5235 that the drive signal is VO (outputs a drive signal to the upper motor 20a, rotates the impeller 22 in the direction of arrow Y in FIG. (S240). After that, this routine is ended and the processing from 5205 is repeated.

In this way, when the cooling water is pumped by the rotation of the impeller 22, the cooling water flowing in from the inlet pipe 25 (the 9th
As shown in the figure, it flows into the pump compartment 21a along the outer periphery of the bearing 23a and is pressurized by the impeller 22. Therefore, the pressure inside the pump compartment 21a increases from the inside of the inlet pipe 25, and the communication hole 25a is closed based on the pressure difference between the switching valve 24 and the backflow of cooling water into the inlet pipe 25. Therefore, the cooling water flowing from the subwater pump 20 (yo) pump compartment 21a to the radiator core 24, that is, heat is radiated by the radiator core 24 and the temperature becomes low, and the flow rate of the cooling water reaching the engine 2 is increased.

As explained above, the cooling system of the second embodiment avoids the cooling water flow pressure loss in the main circuit 3 when the 1'L subwater turbo and pump 20 are stopped, and ensures a sufficient circulation flow rate of the cooling water. Therefore, the engine 2 can be suitably cooled.

Moreover, in order to reduce the water flow resistance in this way, a bypass route that bypasses the subwater pump 20 is not required, so that the ease of mounting on a vehicle can be improved.

For example, when the engine is forced to operate under high load and at low rotation speeds, such as when driving uphill, the subwater pump 20 is naturally driven to pump out cooling water, thereby reducing the cooling water circulating in the main circuit 3. The water flow l can be increased.

As a result, by cooling the engine 2 with the internal combustion engine cooling system using the subwater pump 20, the engine 2 can be suitably cooled at all times even under various driving conditions.

Further, the sub water pump 7 in the first embodiment described above
Unlike the above, the above-mentioned water flow resistance can be reduced and the flow rate of cooling water can be increased by simply controlling the stop and drive of the impeller 22, which is easy to control.

Next, a third example will be described. Incidentally, in the explanation, the explanation will be simplified for the same configuration as the first embodiment described above.

FIG. 11 is a schematic configuration of the cooling system of the third embodiment, and FIG. 12 is a cutaway side view showing the subwater pump 30 used.

As shown in FIG. 11, cooling water is circulated between this cooling system (a radiator, similar to the first embodiment described above) and the engine 2. A main water pump 4 disposed on the reflux side path of the water main circuit 3; a bypass control valve 6 disposed at the connection part of the bypass circuit 5 connecting the introduction side path and the reflux side path of the main circuit 3; A sub water pump 30, which will be described later, is directly incorporated into the introduction side path of the main circuit 3, as well as a hidden water temperature sensor 2a and a rotation speed sensor 2b.
, each sensor such as the vehicle speed sensor 8, and an electronic control circuit (ECU) 10 that is connected to each of these sensors, inputs the signals, and controls the drive of the motor 30a for driving the subwater pump according to the input signal. We are prepared.

Therefore, when the coolant temperature is low, such as immediately after starting the engine, the coolant supplied by the main water pump 4 circulates through a circuit 35 shown by diagonal arrows in the figure, which uses the bypass circuit 5 as its route. On the other hand, when the engine 2 generates heat and the cooling water temperature rises above the set temperature due to an increase in engine load, etc., the bypass circuit 5 is closed by the bypass control valve 6 and the main circuit 3 is opened, as shown by the white arrow in the figure. When the circuit 36 is formed, the high-temperature cooling water is cooled in the radiator 1 by outside air cooling wind (vehicle speed wind or cooling wind from an electric fan (not shown), etc.), reaches the engine 2, and circulates through the main circuit 3.

Next, the subwater pump 30 used in this embodiment will be explained.

As shown in FIG. 12, 1: the sub-water pump 301 has an outer circumferential ring 32 containing an annular arc-shaped magnet 31;
It is rotatably stored in the pump storage groove 3C of b, and an impeller 33 is fitted and fixed to the outer ring 32. That is, the motor 30a for driving the sub-water pump is constituted by the coil 3a of the coil storage portion 3b and the magnet 3 built into the outer circumferential ring 32.

As shown in FIG. 13, this impeller 33 is equipped with four blades 34 rotatably supported and equally divided radially from a support portion 33b located at the center of a main body ring 33a. A stopper 35 for limiting the fall of each blade 34 is provided on the inner peripheral surface of the main body ring 33a near the support portion of the blade so as to protrude toward the blade side. Note that this blade 34 (surface is made of iron, stainless steel, resin, etc.), and the main body ring 3
3a (when the body ring 33a is rotatably supported)
And the pin is assembled to the support portion 33b at the center thereof.

Then, when the coil 3a of the coil storage section 3b is energized based on the energization control by the ECUIO, the impeller 33 integrated with the subwater pump 30 (L) is rotated in the direction shown by M in the figure, and the following The cooling water is pumped by 1 step.The sub water pump 30 with the above configuration
The cooling routine for the engine 2 in the cooling system using the subwater pump 30 is the same as the cooling routine based on the flowchart in FIG. Only the following will be explained in detail.

That is, when the cooling of the engine 2 is provided only by the circulation of cooling water based on the main water pump 4 (during low-temperature cooling water circulation, when the engine 2 is rotating at high speed, when the vehicle is running at high speed, etc.), the motor Turn on the stop signal to 30a and turn on the impeller 3.
3 is stopped, and the blades 34 are placed in a position parallel to the flow of cooling water pumped by the main water pump 4, as shown in FIGS. 13(A) and 13(B). This results in
Assembling the subwater pump 3o whose operation is stopped forms a cooling water passage that allows free passage of cooling water in the area, thereby reducing the pressure loss of the cooling water passing through the area.

And the first. Similar to the second embodiment, since there is no need for a bypass path for reducing water flow resistance, the ease of mounting on a vehicle is improved.

On the other hand, when the cooling water temperature Tw rises and the engine reaches a high-load, low-speed operating state (low engine speed and low vehicle speed), Due to the centrifugal force generated due to rotation and the resistance of the cooling water acting on each blade, each blade 34 is tilted to a position where it abuts the stopper 35, and pressure is applied to the cooling water flowing in from the upstream side, so that the cooling water is The cooling water flow rate circulating through the main circuit 3 is increased.

As a result, by cooling the engine 2 with the internal combustion engine cooling system using the subwater pump 3o, the engine 2 can be suitably cooled at all times even under various driving conditions.

Further, as in the second embodiment described above, the above-mentioned water flow resistance can be reduced and the flow rate of cooling water can be increased by simply controlling the stop and drive of the impeller 33, which is easy to control.

Furthermore, the sub water pump 30 (, t
, has the following effects.

As the discharge amount of the main water pump 4 increases (1: as shown in FIG. 13(D), the upper surface 34a of each blade 34
Since the pressure acting on the side is large and the pressure acting on the bottom surface 34b is small, the top surface 34a and bottom surface 34 of each blade 34
The pressure balance at b changes. As a result, feather 3
41. In order to balance the above-mentioned pressure, the main water pump 4 is moved away from the stopper 35 and returned to an arbitrary angle and held there, thereby inhibiting the flow of cooling water by the main water pump 4 even when the sub water pump 30 is being driven. Installing the pump without having to install the pump reduces water flow resistance in the area.

Therefore, even if the engine speed and vehicle speed are fluctuating around their reference values, by driving the sub-water pump 30 to 1'L,
It is possible to reduce water flow resistance and increase the amount of pumped cooling water, and it is possible to reduce the frequency of occurrence of cavitation in the main water pump 4. Furthermore, pump drive control in such a case can be simplified.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments in any way, and it goes without saying that it can be implemented in various forms without departing from the gist of the present invention.

For example, sub water pump, main water pump 4
．． The bypass control valve 6 etc. are the first. Not limited to the installation position in the main circuit explained in the third embodiment, the 14th@15th@
They may be installed at the positions shown in FIG. 16 and the like.

The effect of 聚咀Ω As described in detail above, the cooling device of the present invention (f).

Without creating a bypass route for the auxiliary fluid pump, which was indispensable in the past, the flow resistance of the heat exchanged fluid when the auxiliary fluid pump is stopped is suppressed, and the circulation flow rate of the heat exchanged fluid based on the main fluid pump is ensured. can do. Therefore, the mountability on a vehicle having a cooled device such as an internal combustion engine is improved.

Also, when the auxiliary fluid pump is driven (Naturally 1:), a larger amount of the fluid to be heat exchanged is circulated toward the equipment to be cooled than when the main fluid pump is driven alone.
Regardless of whether the sub-fluid pump is stopped or running, it is possible to always ensure a sufficient circulation flow rate of the fluid to be heat exchanged, and to suitably cool equipment to be cooled, such as an internal combustion engine.

[Brief explanation of the drawing]

Fig. 1 is a block diagram illustrating the basic schematic configuration of the present invention, Fig. 2 is a schematic configuration of the cooling system of the first embodiment, and Fig. 3 is a partially cutaway view of the subwater pump of the first embodiment. 4 is a view of the subwater pump 7 in the direction of arrow A in FIG. 3, and FIG. 5 is a flowchart of the cooling routine of the first embodiment for cooling the engine 2. Schematic configuration diagram of the cooling system of the embodiment, FIG. 7(A)
7 is a plan view of the subwater pump 20 of the second embodiment.
Figure (B) is a partially cutaway view of the fractured front view shown in Figure 7 (
8 and 9 are explanatory diagrams for explaining the action and effect of the second embodiment, and FIG. 10 is a diagram showing the second embodiment for cooling the engine 2. A flowchart of the cooling routine in the example. FIG. 11 is a schematic configuration diagram of the cooling system of the third embodiment, and FIG. 12 is a broken side view showing the sub water pump 30 of the third embodiment.
), (B), (C) and (D) are explanatory diagrams for explaining the action and effect of the sub water pump 30 of the third embodiment, and FIGS. 14, 15 and 16 are sub water pumps. FIG. 17 is a schematic diagram of a cooling circuit using a conventional subwater pump. 1...Radiator 2...Engine 2a...
Water temperature sensor 2b...Rotational speed sensor 3...Main circuit of cooling water 4...Main water pump 7, 20. 30...Sub water pump 8...
Vehicle speed sensor 10...Electronic control circuit (EC(J)

Claims (1)

[Claims] 1. A heat exchanger that cools a heat exchange fluid that cools a device to be cooled by exchanging heat with air, and a circulation path for a fluid to be heat exchanged formed between the device to be cooled, and the fluid to be heat exchanged. A cooling device for an internal combustion engine, comprising a main fluid pump that is installed in a circulation path and forcibly constantly circulates a fluid to be heat exchanged, and a auxiliary fluid pump that assists the main fluid pump and circulates a fluid to be heat exchanged. A driving means that is driven independently of the main fluid pump and drives the auxiliary fluid pump; and a pump section between the suction side and the discharge side of the fluid to be heat exchanged, which is provided in the auxiliary fluid pump. fluid pumping means that rotates by the drive means and pumps the fluid to be heat exchanged; flow path area changing means that changes the flow path area of the fluid to be heat exchanged in the pump section; and non-operation of the fluid pumping means. A cooling device for an internal combustion engine, comprising: control means for driving and controlling the flow passage area changing means to increase the flow passage area.