JPS638015A - Hot water type heating device for automobile - Google Patents

Abstract

PURPOSE:To improve hot water flow rate regulation precision when a flow rate is low, by a method wherein a flow rate control pump, varying a delivery amount by means of a flow rate regulating valve and the number of revolutions, is situated in a hot water flow passage, and when the number of revolutions of a pump is below a specified value, a flow rate is controlled by means of the opening of a regulating valve. CONSTITUTION:A control circuit 32 performs computing processing by means of an external air temperature 22, an internal air temperature 27, a quantity of solar radiation 28, a set temperature 30, a temperature 23 at the rear of a vaporizer, a water temperature 26, and position information 24 of an actuator 16, and controls an air conditioning control means. In this case, the target stroke amount and the auxiliary target stroke amount of an actuator 16, located in a passage running to a heater core 8, are decided the applied voltage of a water pump 15 is controlled, and a flow rate of hot water is controlled. When the number of revolutions of the water pump 15 is reduced to a lowermost value, a flow rate is controlled through control of an opening by means of the actuator 16. This constitution enables a flow rate during low flow rate operation to be accurately regulated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to an automotive hot water system that adjusts the flow rate of hot water passing through a heating heat exchanger to adjust the air temperature passing through the heating heat exchanger. The present invention relates to a type heating device.

[Conventional technology]

2. Description of the Related Art Hitherto, heating devices or air conditioning devices that heat air by using cooling water that cools an automobile engine as hot water are generally known. Since engine cooling water is generally flowed by a pump driven by the engine, the flow rate of this cooling water varies depending on the engine rotation speed.

Therefore, a heating heat exchanger is installed in parallel with the engine cooling water flow path, and a pump driven by a DC motor G is connected in series with the heating heat exchanger. It is generally known to provide an L amount control valve to control the flow rate of hot water flowing to a heating heat exchanger. Furthermore, there is also generally known a system that does not include a flow rate control valve and controls the flow rate of hot water flowing to a heating heat exchanger by adjusting the meteor of a pump driven by a DC motor.

[Problem that the invention seeks to solve]

In conventional hot water heating systems for automobiles, the flow rate of a pump that flows hot water to a heating heat exchanger is set to the maximum heating amount, and the flow rate is throttled by a flow rate control valve. Furthermore, in a pump that does not include this flow rate control valve and adjusts the flow rate of a pump driven by a DC motor, the flow rate is adjusted by the rotational speed of the DC motor. With such a device, it is very difficult to adjust the flow rate to a low level.

The flow rate control valve has a large difference between the fully closed state and the minimum opening state, and the pump has a maximum of 2 itffi, so it is difficult to adjust the flow rate to a small value. Furthermore, in a pump driven by a DC motor, there is a large difference between the rotational speed O and the minimum rotational speed, and it is difficult to control the rotational speed to a small value. Therefore, in areas where the flow rate of hot water is small, the change in flow rate due to changes in the opening degree of the flow rate control valve or changes in the rotation speed of the DC motor is large; in areas where the flow rate of hot water is large, changes in the degree of opening of the flow rate control valve or changes in the rotation speed of the DC motor are large. The change in flow rate with respect to the change is small.

The present invention has been made in view of the above-mentioned problems, and its purpose is to accurately adjust the flow rate of hot water even in areas where the flow rate of hot water flowing into the heating heat exchanger is small. With the goal.

Means for Solving Problem C] In order to achieve the above-mentioned object, the present invention provides a heating heat exchanger that introduces hot water heated by an automobile engine and heats passing air; A flow rate control valve that is installed in a hot water flow path that supplies hot water to the heat exchanger and adjusts the flow rate of the hot water flow path; and a flow rate control pump that is installed in the hot water flow path and whose discharge flow rate is variable according to its rotation speed. and a control device that controls the opening degree of the flow N control valve to adjust the flow rate of hot water flowing to the heating heat exchanger when the rotation speed of the flow rate control pump is at a low constant value. Adopt practical means.

[Effect]

The present invention having the above configuration will be described in detail. A heating heat exchanger exchanges heat between hot water and air passing through it, heating the air. In order to adjust the temperature of this air, the flow rate of hot water in the heating heat exchanger is adjusted using a flow control valve and a flow control pump.

The flow control valve is conventionally known and changes the cross-sectional area of the hot water flow path. A meteor control pump has a discharge flow rate that changes depending on its rotation speed. The opening degree of this meteor control valve,
The rotation speed of the flow rate control pump is controlled by a control device. This control device controls the rotational speed of the flow rate control pump to a low constant value and adjusts the hot water flow rate by changing the opening degree of the flow rate control valve at this time. In other words, if the rotational speed of the flow rate control pump is low, the hot water flow rate is relatively low. In this low state, 2 more
i! If the opening degree of the L amount control valve is narrowed, the hot water flow rate can be adjusted to be even smaller. In this way, the present invention keeps the hot water flow rate by the flow rate control pump at a small constant value, and controls the opening degree of the flow rate control valve at this time, so that the hot water flow rate flowing into the heating heat exchanger is relatively small. Precisely adjust the state flow rate.

〔Effect of the invention〕

As is clear from the structure and operation of the present invention, the device of the present invention adjusts the opening degree of the flow rate control valve when the flow rate of the flow rate control pump is low, so that the flow rate of hot water flowing into the heating heat exchanger is controlled. , it becomes possible to make small and delicate adjustments.

〔Example〕

FIG. 1 shows the configuration of an embodiment of an air conditioner for an automobile according to the present invention, which is of a reheat type.

In FIG. 1, an inside/outside air switching damper 5 is provided at a connection portion between an air passage 2 of an air conditioner (air conditioner) 1, an outside air intake passage 3, and an inside air intake passage 4. The flow rate of the air selected and taken in by the blower 6 is selected by the blower 6, and then cooled by the evaporator turf, then warmed by the heater core 8, and then passed through the outlet selected by the blower switching damper 9. It is blown out into the vehicle compartment 10. Here, the evaporator trough includes a refrigeration cycle 1 including a compressor 13 to which the driving force of the engine 11 is supplied and cut off via a clutch 12.
A refrigerant is supplied to the heater core 8 through a water valve 15, and cooling water for an engine 11 is supplied to the heater core 8 through a water valve 15 to cool and heat the air, respectively. It is assumed that the pressures in the pipes of the cooling water take-off parts a and b from the engine 11 are approximately equal.

The water valve 15 has a configuration as shown in FIG. 2, and the water valve 15 is configured as shown in FIG. Is the hot water supplied from the 11 side to the heater core 8 side? The mixing ratio between PL't and the flow rate of the cold water that is cooled while flowing within the heater core 8 and is supplied again to the heater core 8 side is determined, and the overall temperature of the engine cooling water supplied to the heater core 8 is determined. .

Referring again to FIG. 1, the air intake passage of the diaphragm 16 is provided with a hot valve 19 that controls opening and closing of a communication passage with the engine intake pipe (not shown) and a cool valve 20 that controls opening and closing of a communication passage with the atmosphere. has been done. Further, a motor pump 21 is provided in a passage leading from the outgoing valve 17 to the heater core 8. The rotation speed of this motor pump 21 can be freely set according to commands from the control circuit 32, and its flow rate is variable. Water valve driving means 37
The actuator opens and closes the hot valve 19 and the cool valve 20, and is an electromagnetic actuator. The water pump driving means 40 consists of a DC motor and a circuit that adjusts the voltage applied to the DC motor. For example, the voltage applied to the DC motor may be adjusted by a resistor, or the voltage applied may be a pulse voltage. The effective value of this pulse voltage is changed using a transistor circuit or the like.

The air conditioner l is provided with various sensors for detecting operating conditions and atmospheric conditions, and condition indicating means for indicating operating conditions, and these input means groups are used for temperature control by the control circuit 32. Provide data. That is, outside temperature information from outside temperature sensor 22, inside temperature sensor 2
The inside temperature information from 7, the solar radiation information from the solar radiation sensor 28, and the target temperature information from the temperature setting device 30 are used as data for calculating the required blowing temperature as described later, and the post-evaporation temperature information from the duct sensor 23 The engine cooling water temperature information from the water temperature sensor 26 is used together with the calculated necessary blowout temperature data to calculate the target stroke amount (target position) of the actuator 16, and the actual position information of the actuator 16 from the position sensor 24 is used to calculate the target stroke amount (target position) of the actuator 16. It is used together with the calculated target position data to calculate the control amount for the actuator.

Further, the switch panel 29, which is one of the condition indicating means,
It is used to indicate various driving modes, such as automatic driving mode and manual driving mode.

When the ignition switch 33 is turned on and a constant voltage is applied by the power supply circuit 34, the control circuit 32 responds to the detection signals from the sensors under the conditions set by the switch panel 29 and temperature setting device 30. Based on this, predetermined arithmetic processing is performed to control various driving means. Here, this driving means includes an inside/outside air switching damper driving means 35 that drives the inside/outside air switching damper 5, a blower driving means 36 that drives the blower 6, a water valve driving means 37 that drives the hot valve I9 and the cool valve 20, There are a blow-off switching damper driving means 38 that drives the blow-off switching damper 9, a pump motor driving means 40 that drives the motor pump 21, and a clutch 12 that disconnects and connects the transmission of driving force from the engine 11 to the compressor 13 as described above.

Next, the main parts of the processing operation by the control circuit 32 will be explained with reference to the flowchart of FIG.

When the ignition switch 33 is turned on, the control circuit 3
2 starts processing. Then the process progresses to step 10
1, step 101 is executed and input signals from the above-mentioned various sensors and human power means are sequentially taken in.

Next, step 102 is executed to calculate the required blowing temperature Tao based on the various data taken in step 101 above. In calculating this temperature Tao, the following formula is used: Tao = Ks - Ts - Kr - Tr - Kat
s-Tam -Ksun 8Tsun -C (However, Ks s Kr -, KamSKsun SC
are constants, Ts is the set temperature or target temperature, Tr is the temperature inside the vehicle, Tan is the temperature outside the vehicle, and T sun is the intensity of solar radiation. ) is used. Further, in step 102, the target stroke amount SW of the actuator 16 is calculated as described above (based on the calculated necessary blowout temperature Tao, post-evaporation temperature information from the duct sensor 23, and engine cooling water temperature information from the water temperature sensor 26).

Next, step 103 is executed to calculate the corrected target stroke -1JsW' of the actuator 16 from the target stroke amount SW calculated in step 102 above.

In the next step 104, the actual water valve opening degree is S.
This is a step in which a signal is output to the valve drive circuit 37 so as to match W'.

The next step 105 is step 7 in which the pump motor applied voltage VW is calculated from the target stroke SW.

Step 106 outputs the VW calculated in step 105 to the bomb guitar drive circuit 40 as a signal.

Figure 4 shows the blowout temperature (fourth
(al), the opening degree of the water valve 15 according to the corrected target stroke SW' (Fig. 4 (b)), and the rotational speed of the motor pump rotation speed 21 (Fig. 4 (C)) according to the pump motor applied voltage VW. Each change is illustrated. The broken line shows the conventional technology, and shows the opening degree of the water valve 15 and the change in the blowing temperature when the rotational speed of the motor pump 21 is kept constant at maximum.

In the case of this embodiment, the target stroke SW is MAXCOOL
The rotation speed of the motor pump 21 is kept at the lowest rotation speed below 50 (%), which is the boundary between 50 (%) and MAX HOT, and the water valve 1
The blowing temperature is adjusted only by the opening degree of No. 5. Moreover,
When the target stroke SW is 50 (%), the water valve 15 is fully opened. Target stroke SW is 50
(%) or more, the opening degree of the water valve 15 does not change and is kept fully open, and the rotation speed of the motor pump 21 is increased to increase the hot water flow rate and adjust the blowing temperature.

As shown in Fig. 4 Ta), the change in the blowout temperature with respect to the target stroke SW is approximately linear, and even in the range where the target stroke SW is close to MAX C00L,
The amount of change in the blowout temperature is approximately constant and is well proportional to the target stroke SW. Thereby, the blowing temperature can be adjusted accurately even in a range where the target stroke SW is relatively small.

In this embodiment, when the target stroke SW is 50 (%) or less, the morph pump rotation speed is constant and only the water valve opening is changed, and when it is 50 (%) or more, the water valve opening is constant and the motor is We tried to adjust the blowout temperature by changing only the pump rotation speed, but the
, (bl, (As shown in C1, a region may be provided in which both the water valve opening degree and the motor pump rotation speed change.

In addition, as shown in FIGS. 6(a), (b), and (C), the rotational speed of the motor pump 21 is set in two stages, that is, low rotational speed and high rotational speed, and the water valve opening degree is adjusted according to each rotational speed. may be changed. In such a case, to prevent hunting, the target stroke SW should be set to 50 (
%) may be provided with hysteresis.

Alternatively, as shown in FIG. 7, only the outgoing water valve 17 may be provided, and this water valve 17 may be driven by the driving means 41.

In the embodiment shown in FIG. 7, the operations corresponding to steps 102 and 103 in FIG. 3 showing the flowchart of the embodiment shown in FIG. Is the operation corresponding to the control? ? The driving means 41 changes the opening degree of the water valve 17 twice according to a command from the I device 32.

As described above, when the present invention is applied to an automobile air conditioner, the change in the blowout temperature with respect to the target stroke SW becomes linear, so that more accurate and easier temperature control is possible than in the conventional system.

Further, in the embodiments described above, only an automobile air conditioner having a cooling function was described, but the present invention can also be applied to an automobile heating device having only a heating function.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an automobile air conditioner which is an embodiment of the present invention, Fig. 2 is a schematic block diagram of the water valve shown in Fig. 1, and Fig. 3 is a main part of the processing according to the present invention. FIG. 4 is a characteristic diagram showing changes in the blowout hot water temperature, water valve opening degree, and motor pump rotation speed with respect to the target stroke SW of the embodiment shown in FIG. 1, and FIGS. 5 and 6 7 is a characteristic diagram showing changes in blowout temperature, water valve opening degree, and motor pump rotation speed with respect to target stroke SW according to another embodiment, and FIG. 7 is a configuration diagram of an automobile air conditioner according to another embodiment. l...Automotive air conditioner, 7...Evaporator. 8... Heater core, 10... Vehicle interior, 11... Engine. 15...Water valve, 21...Motor pump,
32...Control circuit. Representative Patent Attorney Takashi Okabe (MAXCOOL) (MAXHOT) Hiki O-? SW (%n

Claims (1)

[Scope of Claims] A heating heat exchanger that introduces hot water heated by an automobile engine and heats passing air; and a hot water flow path that supplies hot water to the heating heat exchanger; a flow control valve that adjusts the flow rate of the flow path; a flow control pump that is provided in the hot water flow path and whose discharge flow rate is variable according to its rotation speed; and when the rotation speed of the flow control pump is at a low constant value,
A hot water type heating device for an automobile, comprising: a control device that controls the opening degree of the flow control valve to adjust the flow rate of hot water flowing to the heating heat exchanger.