JP5773217B2 - Engine cooling system - Google Patents

Description

  The present invention includes a head cooling water passage for cooling a cylinder head of an engine, a cooling water circulation passage provided in parallel with a block cooling water passage for cooling a cylinder block, a circulation pump for circulating cooling water in the cooling water circulation passage, A state detection sensor for detecting an operating state of the engine, a pump control device for increasing or decreasing the discharge amount of the circulation pump based on a detection result of the state detection sensor, and a flow rate adjusting valve provided in the middle of the block cooling water channel And an engine cooling device.

The engine cooling device increases or decreases the discharge amount of the circulation pump, that is, the circulating flow rate of the cooling water circulating through the cooling water circulation path, based on the detection result of the state detection sensor that detects the operating state of the engine. For this reason, useless consumption of energy for driving the pump can be suppressed by operating the circulation pump in accordance with the operating state of the engine so that the circulation flow rate of the cooling water does not become excessive or insufficient.
In addition, by adjusting the flow rate of the cooling water flowing through the block cooling water channel with the flow rate adjusting valve according to the operating state of the engine, the cooling water flows into the block cooling water channel and the head cooling water channel at a predetermined rate, The cooling efficiency of each of the cylinder head and the cylinder block can be improved.
In the conventional engine cooling device, for example, an electromagnetic flow control valve and a valve control device that electrically controls the flow control operation of the flow control valve in accordance with the operating state of the engine are provided (for example, patents). Reference 1).

JP 2005-36731 A

For this reason, it is necessary to provide a valve control device that electrically controls the flow rate adjustment operation of the flow rate control valve separately from the pump control device, and the flow rate that can be opened and closed without electrical control by the valve control device Compared to the control valve, the acquisition cost of the flow control valve is likely to increase.
Further, since it is necessary to wire a harness for control (energization) between the flow rate control valve and the valve control device, it is necessary to work for the wiring work and to secure a wiring space for the harness.
As a result, the manufacturing cost increases and the arrangement of the flow control valve may be restricted.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an engine cooling device that can suppress an increase in manufacturing cost and that is not easily restricted by the arrangement of a flow control valve.

A first characteristic configuration of an engine cooling device according to the present invention includes a head cooling water passage for cooling a cylinder head of an engine, a cooling water circulation passage provided with a block cooling water passage for cooling a cylinder block in parallel, and the cooling water circulation passage. A circulation pump for circulating cooling water; a state detection sensor for detecting an operating state of the engine; a pump control device for increasing or decreasing a discharge amount of the circulation pump based on a detection result of the state detection sensor; and the block cooling water channel And a flow rate adjusting valve having a urging member that urges the valve body to move toward the valve closing side, and is movable to the valve opening side by the cooling water pressure. The valve body is provided so as to expand as the pressure receiving surface of the water pressure that moves the valve body to the valve opening side moves to the valve opening side, and the pump control device includes: When volume reaches the amount to move the valve body to the valve opening side, in terms of controlling the operation of the circulation pump so that the discharge amount decreases.

The engine cooling device of this configuration is made by paying attention to the fact that the discharge amount of the circulation pump is increased or decreased to an amount that reflects the operating state of the engine based on the detection result of the state detecting sensor that detects the operating state of the engine. It is a thing.
For this reason, the flow rate adjusting valve provided in the middle of the block cooling water passage is energized so that the valve body is movable to the valve opening side by the water pressure of the cooling water, and the valve body is moved to the valve closing side. It has a biasing member.

That is, when the discharge rate of the circulation pump is controlled to be small, the discharge rate reflects the operating state in which the temperature of the cylinder block is difficult to rise, such as when the engine load is low or the engine speed is low. ing.
At this time, since the water pressure of the cooling water is low, the valve body of the flow rate adjusting valve can be kept closed by the urging force of the urging member.
Thereby, the inflow of the cooling water to the block cooling water channel can be prevented or reduced, and the cylinder block can be prevented from being excessively cooled.

In addition, when the circulation pump is controlled to increase the discharge amount, the operation state in which the cylinder block temperature is likely to rise, such as when the engine load is high or the engine speed is high, is reflected in the discharge amount. Yes.
At this time, since the water pressure of the cooling water increases, the valve body of the flow rate adjusting valve can be moved to the valve opening side by the water pressure of the cooling water against the urging force of the urging member.
Thereby, a cooling water can be poured in into a block cooling water channel and a head cooling water channel, and a cylinder block and a cylinder head can be cooled.

Therefore, since the valve body can be opened and closed according to the operating state of the engine while providing a flow rate adjustment valve that can open and close the valve body without electrical control by the valve control device, the flow rate adjustment valve The acquisition cost is difficult to increase.
Moreover, since it is not necessary to wire a control (energization) harness between the flow control valve and the valve control device, wiring work for the harness and wiring space for the harness are not required.
Therefore, with the engine cooling device of this configuration, an increase in manufacturing cost can be suppressed, and the arrangement of the flow rate control valve is not easily restricted.

Moreover, in this structure, a pressure receiving surface is expanded as a valve body moves to the valve opening side. That is, immediately after the valve element moves to the valve opening side, the pressure receiving surface is expanded more than immediately before the valve element moves to the valve opening side, and the water pressure of the cooling water can be received by the wide pressure receiving surface.
For this reason, once the valve body is opened, the pump discharge amount for maintaining the valve body in the open state is smaller than the discharge amount immediately before the valve body is opened.
Therefore, in the present invention, in order to prevent the force that moves the valve body toward the valve opening side, the pump control device, when the discharge amount reaches an amount that can move the valve body toward the valve opening side, By controlling the operation of the circulation pump so as to decrease, the valve body can be maintained in a state of moving to the valve opening side with a small force.
Therefore, with the engine cooling device of this configuration, when cooling the cylinder block and the cylinder head, the valve body is kept moved to the valve opening side with a small discharge amount, and the energy consumption for driving the pump is suppressed. can do.

According to a second characteristic configuration of the present invention, the valve body moved to the valve opening side is held at the valve opening position against the urging force of the urging member, and is held as the discharge amount of the circulation pump decreases. It is in the point provided with the valve body holding part which can cancel a state.

  If it is this structure, the valve body which moved to the valve opening side can be stably hold | maintained in the valve opening position against the biasing force of a biasing member. Further, when the cooling water pressure decreases as the discharge amount of the circulation pump decreases, the valve body can be moved to the valve closing side by the urging force of the urging member that resists the cooling water pressure.

It is a block diagram of an engine cooling device. It is sectional drawing which shows the flow control valve of a valve closing state. It is sectional drawing which shows the flow control valve at the time of valve opening start. It is sectional drawing which shows the flow control valve of a valve opening state. It is explanatory drawing which shows the relationship between the valve closing area | region and valve opening area | region of a flow regulating valve, an engine load, and an engine speed. It is a flowchart which shows the rotation speed control by a pump control apparatus. It is sectional drawing which shows the flow regulating valve of the valve opening state in 2nd Embodiment. It is sectional drawing which shows the flow regulating valve of the valve closing state in 2nd Embodiment. It is sectional drawing which shows the flow regulating valve of the valve opening state in 2nd Embodiment. It is a flowchart which shows the rotation speed control by the pump control apparatus in the engine cooling device of 2nd Embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 shows an engine cooling device according to the invention.
The engine cooling device includes a head cooling water passage 1 for cooling the cylinder head E1 of the automobile engine E, a cooling water circulation passage 3 provided in parallel with a block cooling water passage 2 for cooling the cylinder block E2, and a cooling water circulation passage 3 An electric circulation pump P that circulates cooling water, a temperature sensor S as a state detection sensor that detects the operating state of the engine E, and a pump that increases or decreases the discharge amount of the circulation pump P based on the detection result of the temperature sensor S A control device C and a flow rate adjusting valve V provided in the middle of the block cooling water channel 2 are provided.

A radiator 4, a circulation pump P, and a thermostat valve 5 are connected to the cooling water circulation path 3. The temperature sensor S detects the temperature of the cooling water immediately after passing through the head cooling water channel 1.
When the cooling water temperature is lower than the set temperature, the thermostat valve 5 is kept closed to stop the circulation of the cooling water to the radiator 4, and when the cooling water temperature is higher than the set temperature, the thermostat valve 5 is held open to the radiator 4. Circulate cooling water.

The head cooling water channel 1 and the block cooling water channel 2 are connected in parallel to each other at the circuit portion between the circulation pump P and the thermostat valve 5.
The cooling water in the cooling water circulation path 3 circulates in the order of the engine E, the thermostat valve 5, and the radiator 4 by driving the circulation pump P when the thermostat valve 5 is in the open state.

  A heat exchanger 6 such as a heater was provided across a circulation path portion between the radiator 4 and the circulation pump P and a circulation path portion between the head cooling water passage 1 and the block cooling water passage 2 and the thermostat valve 5. The heat exchange water channel 6a is connected in parallel.

The flow rate adjusting valve V is connected to the downstream side of the water channel portion in the cylinder block E2 in the block cooling water channel 2, and adjusts the flow rate of the cooling water in the block cooling water channel 2.
The flow rate adjusting valve V may be connected to the upstream side of the water channel portion in the cylinder block E2 in the block cooling water channel 2.

As shown in FIGS. 2 to 4, the flow rate adjusting valve V is provided with a cylindrical valve body accommodating portion 7 that communicates with a middle portion of the block cooling water passage 2 in the cylinder block E <b> 2.
An annular valve seat 8 is formed in the valve body accommodating portion 7 toward the downstream side, and is energized so that the disc-shaped valve body 9 and the valve body 9 move toward the valve closing side. A compression spring 10 as an urging member is attached.

The compression spring 10 is mounted between the plug 7 a that closes the opening of the valve body housing portion 7 and the valve body 9.
The valve body 9 is mounted so as to be movable between a valve closing side whose outer peripheral side is in close contact with the valve seat 8 from the downstream side and a valve opening side whose outer peripheral side is separated from the valve seat 8 on the downstream side. The valve can be moved to the valve opening side by the cooling water pressure against the urging force of the compression spring 10.

  The valve body 9 is formed in a disc shape having a smaller diameter than the inner diameter of the valve body housing portion 7 so as to be attached to the inner peripheral surface of the valve body housing portion 7 with a gap. Is configured as a normally closed flow control valve V in which the cooling water flows to the downstream side of the block cooling water passage 2 as it moves to the valve opening side against the urging force of the compression spring 10.

As shown in FIG. 2, the water pressure receiving surface 11 for moving the valve body 9 to the valve opening side is, of the valve body 9 in the closed state where the outer peripheral side of the valve body 9 is in close contact with the valve seat 8. This is formed by a surface 11 a facing the upstream side of the block cooling water channel 2 on the inner peripheral side of the valve seat 8.
Then, as shown in FIG. 3, when the valve body 9 is moved to the valve opening side, the area of the pressure receiving surface 11 is equal to that of the valve seat 8 at the start of valve opening when the outer peripheral side of the valve body 9 is separated from the valve seat 8. The surface 11a facing the upstream side of the block cooling water channel 2 on the inner peripheral side is expanded to an area obtained by adding the contact surface 11b that is in close contact with the valve seat 8.

As shown in FIG. 4, the valve body accommodating portion 7 holds the valve body 9 moved to the valve opening side in the valve open position against the urging force of the compression spring 10 and reduces the discharge amount of the circulation pump P. Accordingly, a valve body holding portion 12 capable of releasing the holding state is provided.
The valve body holding part 12 is configured by forming the valve body 9 from a magnetic body and mounting a permanent magnet 13 inside the plug 7a.

  The magnetic force of the permanent magnet 13 and the urging force of the compression spring 10 are attracted to the permanent magnet 13 and held in the valve-opened position when the valve body 9 is separated from the valve seat 8 by a predetermined pressure by water pressure acting on the pressure receiving surface 11. As the cooling water pressure decreases due to a decrease in the discharge amount of the circulation pump P, the size is set such that the adsorption of the valve body 9 by the permanent magnet 13 is released by the urging force of the compression spring 10.

The pump control device C determines the operating state of the engine based on the detection result of the temperature sensor S, so that the discharge amount of the circulating pump P becomes an amount corresponding to the determined operating state of the engine. Rotational speed control for controlling the rotational speed R is executed.
When the rotational speed of the circulation pump P is increased, the discharge amount is increased, and when the rotational speed of the circulation pump P is decreased, the discharge amount is decreased.

  As shown in FIG. 5, the flow rate adjusting valve V is maintained in a closed state when the engine load is less than the predetermined load A or the engine speed is less than the predetermined speed B, and the engine load is equal to or higher than the predetermined load A. Alternatively, the valve opening state is maintained when the engine speed is equal to or higher than the predetermined speed B.

The rotational speed control by the pump control device C and the operation of the flow rate adjusting valve V will be described with reference to the flowchart of FIG.
The pump controller C stops driving the circulation pump P until the temperature T detected by the temperature sensor S reaches a temperature (for example, 85 ° C.) θ1 at which the thermostat valve 5 is opened (step # 1). .
At this time, the valve body 9 is moved to the valve closing position by the urging force of the compression spring 10, and the flow rate adjusting valve V is held in the closed state as shown in FIG.
Therefore, when the engine load is low or the engine speed is low, such as during warm-up operation of the engine E, for example, the drive of the circulation pump P is stopped and the flow rate control valve V is maintained in the closed state. The circulation of the cooling water in the cooling water circulation path 3 is stopped.

When the detected temperature T reaches a temperature θ1 or higher at which the thermostat valve 5 is opened, the pump control device C determines that the warm-up operation has ended, and starts driving the circulation pump P at the minimum number of revolutions (step) # 1, # 2).
After the drive of the circulation pump P is started, the rotational speed R of the circulation pump P is increased or decreased in the low to medium rotation range in proportion to the detected temperature T until the detected temperature T reaches the set temperature θ2 (step # 3). , # 4).

In step # 3, when the rotational speed R of the circulation pump P is increased or decreased in the low to medium rotation range in proportion to the detected temperature T, the discharge amount of the circulation pump P is small, so that the pressure receiving surface 11 of the valve body 9 is reduced. The working water pressure is low.
Therefore, in an operation state in which the temperature of the cylinder block E2 is difficult to rise, such as when the engine load is medium load or the engine rotation speed is medium rotation speed, the rotation speed R of the circulation pump P is increased or decreased in the low rotation to medium rotation range. 2, the flow rate adjusting valve V is maintained in the closed state as shown in FIG. 2, the cooling water is circulated only through the head cooling water channel 1 in the cooling water circulation channel 3, and the cooling water is circulated through the block cooling water channel 2. Has been stopped.

When the detected temperature T reaches the set temperature θ2 (step # 4), the water pressure acting on the pressure receiving surface 11 rises, and the valve body 9 opens against the urging force of the compression spring 10 as shown in FIG. The move to is started.
When the valve body 9 is separated from the valve seat 8 as the valve body 9 starts moving toward the valve opening side, the area of the pressure receiving surface 11 is expanded.

  For this reason, the pump control device C can perform control so as to decrease the rotational speed R of the circulation pump P immediately after the valve element 9 is opened. For example, when the temperature T detected by the temperature sensor S reaches the temperature θ2 at which the valve body 9 is opened, the pump control device C sets the rotational speed R of the circulation pump P to a value necessary for opening the valve body 9. Set to. The number of rotations of the circulation pump P at this time is a value sufficient to maintain the valve element 9 in the open state.

  Therefore, in this state, the cooling water more than necessary is supplied to the cooling water circulation path 3, and the engine may be overcooled. Therefore, the pump control apparatus C captures the timing when the valve body 9 is opened, and changes the rotation speed of the circulation pump P to a minimum value that can maintain the valve-open state of the valve body 9. The change timing may be set, for example, when a predetermined time elapses after the detected temperature T becomes θ2 and the rotational speed of the circulation pump P is increased.

  Specifically, the pump control device C determines that the detected temperature T is the set temperature so that the water pressure of the cooling water acting on the pressure receiving surface 11, that is, the force for moving the valve body 9 to the valve opening side does not increase more than necessary. When θ2 is reached (step # 4), the rotational speed R of the circulation pump P is decreased by a predetermined rotational speed Δr, and the valve body 9 is moved to the valve opening side with a small force (step # 5).

When the valve body 9 moves to the valve opening side, the cooling water discharged from the circulation pump P flows into the block cooling water channel 2 and the head cooling water channel 1 at a predetermined rate, and the cylinder block E2 and the cylinder head E1 are cooled. Is done.
As the detected temperature T rises from this state, the rotational speed R of the circulation pump P is increased or decreased in the high speed range in proportion to the detected temperature T (step # 6).
For this reason, when the valve body 9 moves to the valve opening side again due to the increase in the coolant pressure as the discharge amount of the circulation pump P increases, the valve body 9 is separated from the valve seat 8 by a predetermined distance as shown in FIG. Thus, the valve body 9 is attracted to the permanent magnet 13 and held in the valve open position.

  Therefore, in an operating state in which the temperature of the cylinder block E2 is likely to rise, such as when the engine load is high or the engine speed is high, the flow rate adjusting valve V increases or decreases the rotational speed R of the circulation pump P in the high speed range. Is maintained in the valve open state, and the cooling water is circulated through the head cooling water passage 1 and the block cooling water passage 2 in the cooling water circulation passage 3.

In the state where the valve body 9 is held at the valve open position, the rotational speed R of the circulation pump P decreases as the detected temperature T decreases, and as a result, the water pressure of the cooling water is applied to the urging force of the compression spring 10. When the valve body 9 is reduced to a size that cannot be held at the valve open position, the suction of the valve body 9 by the permanent magnet 13 is released by the biasing force of the compression spring 10 that resists the suction force of the permanent magnet 13. Can do.
When the detected temperature T falls below the set temperature θ2, the valve body 9 can be held at the closed position.

[Second Embodiment]
7 to 10 show another embodiment of the engine cooling device according to the present invention.
In this embodiment, instead of the normally closed flow control valve V shown in the first embodiment, a normally open flow control valve V is provided.
As shown in FIGS. 7 to 9, the flow rate adjusting valve V is provided with a cylindrical valve body accommodating portion 7 formed in a cylinder block E <b> 2 that communicates with a middle portion of the block cooling water channel 2 from a right angle direction. .

  At one end of the valve body housing portion 7, the cooling water in the circulation path portion of the cooling water circulation path 3 downstream of the circulation pump P and upstream of the head cooling water path 1 and the block cooling water path 2. A pilot pressure introduction passage 14 for introducing the water pressure as a pilot pressure is communicated.

The valve body accommodating portion 7 is urged so that the spool type valve body 9 is movable to the valve opening side by the pilot pressure of the pilot pressure introduction passage 14 and the spool type valve body 9 is moved against the pilot pressure. A compression spring 10 as an urging member is attached.
The compression spring 10 is mounted between the plug 7 a that closes the other end side of the valve body housing portion 7 and the spool type valve body 9.

  The spool type valve element 9 includes a first communication path 15a and a second communication path 15b that are opened by communicating the upstream side 2a and the downstream side 2b of the block cooling water channel 2, and the upstream side 2a and the downstream side of the block cooling water channel 2. A blocking portion 15c that blocks the communication with the side 2b and closes the valve, and the blocking portion 15c is disposed between the first communication path 15a and the second communication path 15b.

The rotational speed control by the pump control device C and the operation of the flow rate adjusting valve V in the present embodiment will be described with reference to the flowchart shown in FIG.
When the engine load is low or the engine speed is low, such as when the engine E is warming up, the pump controller C detects the temperature T detected by the temperature sensor S and the thermostat valve 5 is opened. Until the temperature reaches a certain temperature (for example, 85 ° C.) θ1, the driving of the circulation pump P is stopped (step # 10).
At this time, as shown in FIG. 7, the spool-type valve body 9 communicates the upstream side 2a and the downstream side 2b of the block cooling water passage 2 via the first communication passage 15a by the urging force of the compression spring 10. The flow control valve V is held in the open state.

When the temperature T detected by the temperature sensor S reaches a temperature θ1 or higher at which the thermostat valve 5 is opened, the pump control device C determines that the warm-up operation has ended, and drives the circulation pump P at the minimum rotational speed. Start (steps # 10 and # 11).
After the detected temperature T reaches the temperature θ1, the rotational speed R of the circulation pump P is increased or decreased in proportion to the detected temperature T detected by the temperature sensor S (step # 12).

  In step # 12, the rotation speed R of the circulation pump P is proportional to the detected temperature T in an operating state in which the temperature of the cylinder block is unlikely to rise until the detected temperature T reaches the set temperature θ2 from the start of driving of the circulating pump P. As shown in FIG. 8, the spool type valve element 9 is moved by the pilot pressure that resists the urging force of the compression spring 10, and the upstream side 2 a of the block cooling water channel 2. And the downstream side 2b are moved to the valve closing position where the communication with the blocking part 15c is blocked, and the flow rate adjusting valve V is held in the valve closed state.

In step # 12, the rotational speed R of the circulation pump P is set in proportion to the second detected temperature T2 in an operating state in which the temperature of the cylinder block is likely to rise after the second detected temperature T2 reaches the set temperature θ2. During the increase / decrease in the high rotation range, as shown in FIG. 9, the spool type valve element 9 is further moved by the pilot pressure against the urging force of the compression spring 10, and the upstream side 2 a and the downstream side of the block cooling water channel 2. 2b moves to the valve opening position where it communicates with the second communication passage 15b, and the flow rate adjustment valve V is held in the valve open state.
For this reason, the cooling water discharged from the circulation pump P flows into the block cooling water channel 2 and the head cooling water channel 1 at a predetermined rate, and the cylinder block E2 and the cylinder head E1 are cooled.

As the detected temperature T decreases, the rotational speed R of the circulation pump P decreases. As a result, the pilot pressure resists the urging force of the compression spring 10 and causes the spool type valve element 9 to pass through the second communication passage 15b. Thus, the spool type valve element 9 moves to a position where the communication between the upstream side 2a and the downstream side 2b of the block cooling water channel 2 is blocked by the blocking part 15c.
When the detected temperature T falls below the set temperature θ2 and the driving of the circulation pump P is stopped, the spool-type valve body 9 is moved upstream and downstream of the block cooling water channel 2 by the urging force of the compression spring 10. 2b can be moved to the valve opening position where it communicates with the first communication passage 15a, and can be held in the valve open state.
Other configurations are the same as those of the first embodiment.

[Other Embodiments]
1. The engine cooling device according to the present invention may include a flow rate adjusting valve V in which the spring characteristic of the compression spring as the biasing member is adjusted so that the opening degree of the valve body 9 gradually increases.
2. The engine cooling device according to the present invention may include a temperature sensor S as a state detection sensor on the inlet side of the head cooling water channel 1, the outlet side of the block cooling water channel 2, the upstream side of the circulation pump P, or the like.

  The engine cooling device according to the present invention can be used as a cooling device for various engines such as gasoline engines and diesel engines.

DESCRIPTION OF SYMBOLS 1 Head cooling water channel 2 Block cooling water channel 3 Cooling water circulation channel 9 Valve body 10 Energizing member 11 Pressure receiving surface 12 Valve body holding part C Pump control device E Engine E1 Cylinder head E2 Cylinder block P Circulation pump S Condition detection sensor V Flow control valve

Claims (2)

A head cooling water passage for cooling the cylinder head of the engine, and a cooling water circulation passage provided with a block cooling water passage for cooling the cylinder block in parallel with each other;
A circulation pump for circulating the cooling water in the cooling water circulation path;
A state detection sensor for detecting the operating state of the engine;
A pump control device that increases or decreases the discharge amount of the circulation pump based on the detection result of the state detection sensor;
A flow rate adjustment having a valve body provided in the middle of the block cooling water passage and movable to the valve opening side by the water pressure of the cooling water, and an urging member for urging the valve body to move to the valve closing side With a valve ,
The valve body is provided so as to expand as the pressure receiving surface of the water pressure that moves the valve body to the valve opening side moves to the valve opening side,
The pump control device is an engine cooling device that controls the operation of the circulation pump so that the discharge amount decreases when the discharge amount reaches an amount by which the valve body is moved to the valve opening side . A valve body holding portion that holds the valve body that has moved to the valve opening side at a valve opening position against the urging force of the urging member and that can release the holding state as the discharge amount of the circulation pump decreases. The engine cooling device according to claim 1 , comprising:

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