JP5509813B2 - Fluid control valve - Google Patents

Description

  The present invention relates to a fluid control valve that has a valve portion interposed in a fluid flow path and controls the valve section so as to open and close the flow path.

  2. Description of the Related Art An engine water stop technology system is known that improves warm-up performance, fuel consumption, and emissions by stopping the engine coolant circulation with a valve in a vehicle. When a thermostat valve is used as the valve of this system, if the operation of the vehicle compartment heater is required when the engine is cold, the engine cooling water is at a low temperature or the temperature is rising, and the thermostat valve reaches the temperature of the cooling water. In order not to fully open (self-opening) based on, for example, a temperature sensing part disposed in cooling water as disclosed in Patent Document 1 is forcibly heated with a heating element, and the temperature sensing part is expanded (operated), It is conceivable to use a fluid control valve that opens (fully opens) the thermostat valve and distributes cooling water to the vehicle compartment heater.

Japanese Patent Laid-Open No. 2003-328753

  However, like the fluid control valve of Patent Document 1, in order to open the thermostat valve, when a heater that does not have a self-temperature adjusting function such as a nichrome heater is used as the heating element, the temperature sensing portion expands and the thermostat valve is fully opened. Even after the temperature is increased, the temperature sensitive part is overheated and excessively expanded, and the temperature sensitive part may be damaged. On the other hand, it is conceivable that the opening / closing of the thermostat valve is detected by the opening sensor and the heating of the temperature sensing part is controlled according to the detected opening / closing state, that is, the valve part is controlled. There is a problem that the structure is complicated.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a fluid control valve that controls the valve portion by estimating the opening and closing of the valve portion (thermostat valve) with a simple structure.

The first technical means taken in the present invention to solve the above technical problem has a temperature sensing part and a valve part interposed in the fluid flow path, and the temperature sensing part is heated by a heating element. The valve portion opens and closes in response to expansion of the temperature sensing portion, and controls the valve portion so as to open and close the flow path. One fluid temperature detecting means is provided, and a second fluid temperature detecting means is provided downstream from the valve portion, and the first temperature detected by the first fluid temperature detecting means and the second fluid temperature detecting means detect An estimation means for estimating the opening and closing of the valve portion, comparing the difference between the first temperature and the second temperature with a predetermined first threshold, When the difference from the second temperature is larger than the first threshold, the flow system for performing control to open the valve unit And a valve.
In a case where the difference between the first temperature and the second temperature is equal to or less than the first threshold value while performing control for opening the valve portion in the fluid control valve, the second technical means, The control for opening the valve portion was stopped.
According to a third technical means, in the fluid control valve, the difference between the first temperature detected by the first fluid temperature detecting means at the first time point and the second temperature detected by the second fluid temperature detecting means is calculated. A first time point temperature difference is obtained by calculating, and a first temperature detected by the first fluid temperature detecting means at a second time point after a lapse of a predetermined time from the first time point and the second fluid temperature detecting means are A second time point temperature difference is obtained by calculating a difference from the detected second temperature, the first time point temperature difference is compared with the second time point temperature difference, and the first time point temperature difference is the second time point temperature. When it is smaller than the difference, the valve portion is controlled to open.
In a fourth technical means, in the fluid control valve, when the first temperature or the second temperature becomes equal to or higher than a predetermined second threshold after stopping the control for opening the valve portion, the fluid It was decided to end the control of the control valve.
According to a fifth technical means, in the fluid control valve, the fluid control valve is disposed between the engine and a vehicle compartment heater, and when there is no request for heating the vehicle interior by the vehicle compartment heater, the valve unit The control of the fluid control valve is terminated after the control for opening the valve is stopped.

ADVANTAGE OF THE INVENTION According to this invention, the fluid control valve which estimates the opening / closing of a valve part with a simple structure and controls a valve part can be provided.

1 is a schematic diagram showing an engine cooling circuit to which a fluid control valve according to the present invention is applied. Schematic which shows the valve closing state of the fluid control valve based on the Example of this invention. Schematic which shows the valve opening state of the fluid control valve which concerns on the Example of this invention. The fluid control valve which concerns on this invention, and the state figure which shows the temperature progress of the fluid by a control flow. The flowchart which shows the control flow of the fluid control valve which concerns on this invention.

  Embodiments of the present invention will be described below with reference to FIGS.

  FIG. 1 is a schematic diagram showing an engine cooling circuit C on which a fluid control valve 100 according to an embodiment of the present invention is mounted. FIG. 2 is a schematic diagram illustrating a closed state of the fluid control valve 100 according to the embodiment of the present invention. FIG. 3 is a schematic view showing the open state of the fluid control valve 100 according to the embodiment of the present invention.

  The engine cooling circuit C includes an engine 1, a pump 2, a radiator 3, a thermostat 4, a vehicle compartment heater 5, and a fluid control valve 100. Cooling water (fluid) is circulated in the engine cooling circuit C by a pump 2 driven by the engine 1.

  The fluid control valve 100 and the vehicle compartment heater 5 are disposed (intervened) in a heater circuit (fluid flow path) C1 that communicates with the pump 2 substantially from the engine 1.

  The radiator 3 and the thermostat 4 are disposed in a radiator circuit C <b> 2 that communicates from the engine 1 to the pump 2. When the cooling water reaches a predetermined temperature after the engine 1 is started, the thermostat 4 is opened, and the cooling water circulates through the radiator 3 and dissipates heat from the radiator 3 to be cooled.

  The fluid control valve 100 has an inlet 11 on one end side, an outlet 12 on the other end side, and a partition wall 13 in which a through hole (flow path) 13a penetrating in the center is formed between the inlet 11 and the outlet 12. The housing 10 is provided. The cooling water flows from the inlet 11 to the outlet 12 through the through hole 13a.

  A cylindrical piston 20 that extends through the through hole 13a and protrudes is fixed in the housing 10. A heating element 60 that generates heat when energized is provided at the tip 22 of the piston 20. An electric wire E energizing the heating element 60 is inserted into the piston 20 and led out of the housing 10. The electric wire E is in communication with the control means D. A substantially bottomed cylindrical case 30 in which the piston 20 is inserted on one end side is externally inserted on the tip end side of the piston 20 so as to be movable relative to the piston 20. An annular valve body 40 having an outer diameter larger than the inner diameter of the through hole 13 a and opening and closing the through hole 13 a is fixed to the outer periphery of the case 30 so as to be movable integrally with the case 30. On the outer periphery of the piston 20, there is provided a disc-shaped partition plate 21 that defines the space S in the case 30 and is hermetically sealed. The space S is filled with a thermally expandable wax W. The case 30, the wax W and the partition plate 21 constitute a temperature sensing unit 50, and when the wax W is heated and expanded by the heating element 60, the case 30 moves in a direction away from the piston 20, thereby operating the temperature sensing unit 50. To do.

  A cylindrical cover 70 that is integrally fixed to the housing 10 with a gap between the case 30 and the outer periphery of the case 30 is disposed outside the case 30 in the radial direction. A lattice-like lattice 71 is continuously formed on the housing 10 side of the cover 70 and is fixed to the housing 10. The grid 71 reduces the resistance of the cover 70 to the circulation of the cooling water in the housing 10. The lattice 71 moves when the temperature sensing unit 50 moves away from the piston 20, that is, the valve body 40 integrated with the temperature sensing unit 50 opens (opens) the through-hole 13 a and allows the coolant to flow. When this is done, the temperature sensing unit 50 can be exposed to the cooling water. On the radially outer side of the cover 70, one end is engaged with the valve body 40, the other end is engaged with the housing 10, and the valve body 40 is attached in the direction of the partition wall 13 so that the through hole 13a is closed (closed). A coil spring 80 is provided.

  A first temperature sensor (first fluid temperature detection means) 91 is provided on the inlet 11 side (upstream side) of the valve body 40, and a second temperature sensor (on the downstream side) from the valve body 40 is provided. Second fluid temperature detecting means) 92 is provided. The first temperature sensor 91 and the second temperature sensor 92 are in communication with the control means D. The control means D also serves as estimation means for comparing the first temperature T1 and the second temperature T2 to estimate the opening / closing of the valve body 40. Since the cooling water does not flow when the valve body 40 is closed, the temperature difference (difference) between the first temperature T1 detected by the first temperature sensor 91 and the second temperature T2 detected by the second temperature sensor 92. Occurs. Note that immediately after the engine 1 is started, the first temperature T1 and the second temperature T2 are substantially the same even when the valve body 40 is closed. After the engine 1 is started, when the valve body 40 is opened, the cooling water flows, so the first temperature T1 and the second temperature T2 are substantially the same.

  Next, the operation of this embodiment will be described with reference to FIG.

  FIG. 4 is a state diagram showing a fluid temperature course according to the fluid control valve and the control flow according to the present invention.

  After the engine 1 is started, the cooling water in the engine 1 is warmed and the water temperature rises to convection. In the heater circuit C1 communicating with the engine 1, the first water temperature of the first temperature sensor 91 disposed on the upstream side of the valve body 40 close to the engine 1 (the flow path length from the engine 1 to the valve body 40 is short). T1 detects the temperature of the cooling water that has been heated and convected, and rises (region I). The second water temperature T2 of the second temperature sensor 92 disposed on the downstream side of the valve body 40 is separated from the engine 1 with the vehicle compartment heater 5 interposed in the middle of the heater circuit C1 (the vehicle compartment heater 5 is interposed from the engine 1). Since the flow path length extending to the valve body 40 is long), there is almost no influence of the convection of the warmed cooling water in the engine 1, and the water temperature at the start is maintained (region II). .

  For example, immediately after the engine 1 is started, when heating of the vehicle interior by the vehicle interior heater 5 is requested, the heating element 60 is energized to heat the temperature sensing unit 50. The temperature sensing unit 50 stores heat by heating the heating element 60, undergoes a phase change from a solid phase to a liquid phase, and the volume expands after the phase change. As the volume expands, the opening of the valve body 40 gradually increases, the cooling water flows through the through-hole 13a, and the cooling water that is being heated comes into contact with the second temperature sensor 92. The second temperature T2 detected by the second temperature sensor 92 rises due to the cooling water being heated (region III). As the opening degree of the valve body 40 increases, the cooling water that has come into contact with the first temperature sensor 91 immediately comes into contact with the second temperature sensor 92, and the temperature difference between the second temperature T2 and the first temperature T1. Is smaller, the control means (estimating means) D determines that the valve body 40 is substantially fully opened, that is, the temperature sensing unit 50 has expanded to a maximum extent. The control means D stops energization to the heating element 60 in order to prevent a problem due to excessive expansion due to continuation of energization to the heating element 60 (region IV). As the energization is stopped, the heating of the heating element 60 is stopped, and the volume of the temperature sensing unit 50 is maintained or reduced. At this time, the valve body 40 is in the middle of opening the valve, and the difference between the second temperature T2 and the first temperature T1 increases, so that the opening degree of the valve body 40 is increased (so that the valve body 40 is fully opened). Then, the heating element 60 is energized (area V).

  On the other hand, the cooling water is close to the self-opening temperature TB of the valve body 40, and as the opening degree of the valve body 40 increases, the heated cooling water circulates through the through-hole 13 a and passes through the lattice 71. 50. The temperature sensing unit 50 receives heat from the raised cooling water, and the valve body 40 comes to self-open. Thereby, expansion of the temperature sensing unit 50 is performed based on the temperature of the cooling water without depending on the heating of the heating element 60 (area VI). The temperature sensing unit 50 is prevented from overheating due to heating of the heating element 60. The self-opening temperature TB is a temperature at which the valve body 40 is fully opened without energizing the heating element 60.

  Further, when there is no request for heating of the passenger compartment by the passenger compartment heater 5, the first temperature T1 and the second temperature T2 are increased by the convection of the warmed cooling water in the engine 1, and the valve element 40 self- When the valve opening temperature TB is reached, the valve is opened, and cooling water flows through the heater circuit C1.

  Next, the control of the present embodiment will be described with reference to FIG.

  FIG. 5 is a flowchart showing a control flow of the fluid control valve according to the present invention.

  In this control, when heating of the vehicle interior by the vehicle interior heater 5 is requested, the first temperature T1 and the second temperature T2 are set so that the valve body 40 is fully opened quickly in order to distribute the cooling water to the vehicle interior heater 5. The opening / closing or opening degree of the valve body 40 is estimated based on the above, and the temperature sensing unit 50 is heated by the heating element 60 based on the estimation result (the valve body 40 is controlled to open) and self-opening. The energization of the heating element 60 is stopped at a temperature lower than the valve temperature TB (the control for opening the valve element 40 is stopped), and the temperature sensing unit 50 expands excessively due to heat from the cooling water and heating from the heating element 60. To prevent the occurrence of malfunctions.

  First, after the engine 1 is started (started), it is determined whether heating of the vehicle interior by the vehicle interior heater 5 is requested (step 1: S1). If required, the first temperature T1 and the second temperature T2 are detected before and after a predetermined time, and the temperature differences TS1 and TS2 between the first temperature T1 and the second temperature T2 are calculated (steps). 2: S2, Step 3: S3), the temperature differences TS1, TS2 around the predetermined time are compared (Step 4: S4). When the temperature difference TS2 is larger than the temperature difference TS1, that is, when the temperature difference increases as time elapses, since the opening degree of the valve body 40 is small, a valve opening signal (current to the heating element 60) is generated. Turn on (step 6: S6). If the temperature difference TS2 is smaller than the temperature difference TS1, that is, if the temperature difference decreases as time elapses, then the temperature difference between the first temperature T1 and the second temperature T2 is compared with the threshold value TA (step) 5: S5). The threshold value TA is a temperature difference between the first temperature T1 and the second temperature T2 when the valve body 40 is substantially fully opened. When the temperature difference is larger than the threshold TA, the opening degree of the valve body 40 is small, and the valve opening signal is turned on to heat the heating element 60 in order to increase the opening degree (step 6: S6). When the temperature difference is equal to or less than the threshold value TA, the temperature sensing unit 50 is expanded to a maximum extent and the valve body 40 is in a fully open state, so that it is prevented from being excessively expanded due to heating by the heating element 60 and causing problems. Then, the valve opening signal is turned OFF (step 7: S7). Next, the first temperature T1 is compared with the self-opening temperature TB (step 8: S8). When the first temperature T1 is equal to or higher than the self-opening temperature TB, the expansion of the temperature sensing unit 50 is performed based on the temperature of the cooling water without depending on the heating of the heating element 60. Therefore, the control is terminated with the valve opening signal OFF. (End) In Step 8, instead of the first temperature T1, the second temperature T2 may be compared with the self-opening temperature TB.

  When there is no longer a request for heating the passenger compartment by the passenger compartment heater 5, it is determined whether or not there is a request for heating (step 1: S1), the valve opening signal is turned off, and the control ends (end).

  It should be noted that the control means (estimating means) D based on the first temperature T1 and the second temperature T2 during the period from when the cooling water reaches the self-opening temperature TB of the valve body 40 to the opening temperature of the engine 1 FIG. 4 shows the state of the signal (energization to the heating element 60) and the opening / closing state of the valve body (valve) 40.

40 ... Valve body (valve part)
91 ... 1st temperature sensor (1st fluid temperature detection means)
92 ... Second temperature sensor (second fluid temperature detecting means)
100: Fluid control valve C1: Heater circuit (fluid flow path)
D: Control means (estimation means)
T1 ... first temperature T2 ... second temperature TA ... threshold

Claims (5)

A temperature sensing section and a valve section interposed in the fluid flow path ; the temperature sensing section is heated and expanded by a heating element; the valve section opens and closes in response to expansion of the temperature sensing section ; A fluid control valve for controlling the valve part to open and close,
First fluid temperature detection means is provided upstream from the valve portion, and second fluid temperature detection means is provided downstream from the valve portion,
Comparing the first temperature detected by the first fluid temperature detection means with the second temperature detected by the second fluid temperature detection means, the estimation means for estimating the opening and closing of the valve unit ,
The difference between the first temperature and the second temperature is compared with a predetermined first threshold value, and when the difference between the first temperature and the second temperature is greater than the first threshold value, the valve portion is opened. A fluid control valve that controls the valve. Oite to claim 1,
When the difference between the first temperature and the second temperature is less than or equal to the first threshold value while performing the control to open the valve unit, the fluid control valve that stops the control to open the valve unit . In claim 1 or claim 2,
Obtaining a first time point temperature difference by calculating a difference between the first temperature detected by the first fluid temperature detecting means at the first time point and the second temperature detected by the second fluid temperature detecting means;
Calculating a difference between a first temperature detected by the first fluid temperature detecting means and a second temperature detected by the second fluid temperature detecting means at a second time after a predetermined time has elapsed from the first time. To find the second time point temperature difference,
A fluid control valve that compares the first time point temperature difference with the second time point temperature difference and performs control to open the valve unit when the first time point temperature difference is smaller than the second time point temperature difference. In claim 2,
A fluid control valve that terminates the control of the fluid control valve when the first temperature or the second temperature becomes equal to or higher than a predetermined second threshold after stopping the control for opening the valve portion. In any one of Claims 1 thru | or 4,
The fluid control valve is disposed between the engine and the vehicle compartment heater,
A fluid control valve that terminates the control of the fluid control valve after stopping the valve opening control when there is no request for heating of the vehicle interior by the vehicle interior heater.

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