JPS598513A - Room heating device of car mounted with water-cooled engine - Google Patents

Abstract

PURPOSE:To expedite room heating operation at cold starting of an engine, by providing a circulative route circulating cooling water in a high temperature part of a cooling water jacket, via a heat exchange part with exhaust gas and a room heating heater core, and a circulative route circulating cooling water except in the high temperature part via a radiator. CONSTITUTION:Cooling water in a water jacket 1b of a cylinder block part partitioned by a partition P flows in through a circulative route 20 interposing a radiator 21 and is cooled by driving of a water pump 23, and then returned from a flow inlet 17 into the water jacket 1b. While cooling water in a water jacket 1a of a cylinder head part is guided by driving of a water pump 22 firstly to a heat exchanger 10 to be heated by exhaust gas flowing in an exhaust passage 9, and then guided to a heater core 5 of an air conditioner to heat air conditioning air, thereafter the water is returned from a flow inlet 2 into the water jacket 1a. At completion of warming operation, a selector valve 12 is selectively operated to an opening side of a bypass passage 11, while a thermostat valve 16 is opened to the side of a bypass passage 14, and the cooling water is cooled by a radiator 15.

Description

[Detailed description of the invention] The present invention relates to a heating device for a vehicle equipped with a water-cooled engine.

In order to improve the comfort of a vehicle during winter operation, heating the interior of the vehicle is essential. Currently, as a heating device, if the vehicle is equipped with a water-cooled engine, a hot water type device that uses the heat of Ennon cooling water is used.

However, in conventional hot water heating systems, the temperature of the cooling water does not rise sufficiently, especially when the Ennon is cold, and therefore the heating does not work sufficiently. This is because during engine cooling, the head of the engine is quite hot, but the block remains at a low temperature, so the cooling water flowing through the entire cooling water mantle of the engine body is This is thought to be because the temperature is averaged out as a whole and becomes low.

Therefore, in JP-A No. 5TT-, 2O,;TLL, G, when the engine is cold, the engine cooling water is kept at as high a temperature as possible by flowing the cooling water only to the head section where the temperature is high. A water passage mechanism has been proposed. According to this water passage mechanism, it is possible to raise the temperature of the cooling water to some extent, but even with this, there are cases where it is not possible to obtain a sufficient heating device.

Another method is to further heat cooling water that has been heated to a certain degree using the heat of the exhaust gas, and use this further heated cooling water for space heating. However, there were cases where sufficient heating temperature could not be obtained. The above-mentioned drawbacks of conventional heating devices are particularly noticeable in diesel engines with good combustion efficiency, and improvements have been desired.

Therefore, in view of the above-mentioned drawbacks of the hot water heating system that uses the heat of cooling water, the present invention further heats the cooling water heated in the cylinder high temperature section using the heat of exhaust gas.
The object of the present invention is to provide a heating device for a vehicle equipped with a water-cooled ennon, which can supply water to a heating heater core to thereby obtain a sufficient heating temperature.

That is, the heating device for a vehicle equipped with a water-cooled engine according to the present invention extracts cooling water from the high-temperature part of the cooling water sleeve of the ennon main body, is installed in the exhaust passage, and heats the cooling water by heat exchange with exhaust gas. a first cooling water circulation path that returns the cooling water to the high temperature part of the cooling water can through an exchanger and a heater core for heating the vehicle interior; a first water pump provided in the first cooling water circulation path; A first cooling water circulation path connecting a portion of the cooling water mantle of the ennon main body other than the high temperature section and the radiator, and a λth water pump provided in the second cooling water circulation path. This is a characteristic feature.

Note that as the high temperature portion of the cooling water cannulation, for example, a cooling water cannulation of a cylinder head may be used.

The heating system for a vehicle equipped with a water-cooled engine of the present invention having the above structure has a cooling water circulation path for heating connected to the high temperature part of the cooling water mantle, and a cooling water for the radiator connected to a part of the cooling water mantle other than the high temperature part. The cooling water is taken out from the part of the cooling water mantle that is relatively high temperature even when the Ennon is cold, and this cooling water is further heated by fully utilizing the heat of the exhaust gas. Since the sufficiently heated cooling water is sent to the heating heater core, a sufficient heating temperature can be obtained even when the engine is cold.

A heating system for a vehicle equipped with a water-cooled engine according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a heating system for a vehicle equipped with a water-cooled ennon according to a first embodiment of the present invention.

In FIG. 1, E indicates a water-cooled engine installed in a car (not shown).A cooling water mantle 1 is provided outside the combustion chamber of this Ennon E. 1 is divided into the following parts by a partition wall P, and constitutes a cylinder head part water cannula 1as and a cylinder prop part water cannula 1b.

An inlet d2 and an outlet 3 for cooling water are formed in the cylinder head water cannula 1a. The inflow port 2 and the outflow port 3 are communicated by a heating cooling water circulation path 4, and a heater core 5, which is a heat exchanger, is interposed in the circulation path 4.

This heater core 5 heats the air sent by the blower 6 by heat exchange with the heated cooling water passing through the heater core 5.

This heated air is introduced into the vehicle interior for heating purposes. The blower 6 is operated by a manual blower switch 7 with switches OFF, LOWX'HI.

In the figure, reference numeral 8 indicates an exhaust manifold, and an exhaust passage 9 is connected to the exhaust manifold 8. A heat exchanger 10 is provided in the middle of the exhaust passage 9 between the outlet 3 of the circulation route 4 and the heater core 5, and the cooling water sent to the heater core 5 through the circulation route 4 is transferred to this heat exchanger 10. It is heated in the heat exchanger 10 by exhaust gas. A piston passage 11 is formed in the exhaust passage 9 and bypasses a portion where a heat exchanger 10 is provided. The temperature of the cooling water flowing into the circulation path 4 from the outlet 3 is sufficiently high in the bypass passage 11, and the cooling water is transferred to the heat exchanger 10.
This is a place where exhaust gas can flow when there is no need to heat it. For this reason, a switching valve 12 is provided at the branch of the bypass passage 11 from the exhaust passage 9 to adjust the exhaust gas between the exhaust passage 9 where the heat exchanger 10 is provided and the bypass passage 11. It is designed to flow.

An on-off valve 13 is provided on the downstream side of the heater core 5 in the circulation passage 4, and this on-off valve 13 is closed when the heating device is not needed to prevent cooling water from being sent to the heater core 5.

The circulation path 4 is provided with a bypass passage 14 that bypasses the heater core 5 and the heat exchanger 10. A radiator 15 is provided in the pipe/gas passage 14 to cool the cooling water flowing through the pipe/gas passage 14.

This bypass passage 14 supplies cooling water to the heat exchanger 10 and the heater, and a circulation path 4 on the core 5 side when heating is not performed.
This is to prevent it from flowing into the environment. For this reason, a switching valve 16 is installed at the branch part of the circulation path 4 and the bypass path 14.
is provided so that the cooling water can be regulated and flowed between the circulation path 4 in which the heat exchanger 10 and the like are provided and the bypass passage 14.

On the other hand, a cooling water inlet 1γ and an outlet 18 are also formed in the cylinder block water jacket 1b.

The inlet 17 and the outlet 18 are communicated with each other by a radiator cooling water circulation path 20.
0 is provided with a radiator 21. The heating circulation path 4 and the radiator circulation path 20 are independent from each other. Therefore, circulation route 4
A first water pump 22 and a second water pump 023 are separately provided in the circulation path 20 and the circulation path 20, respectively. The first water pump 22 is driven and controlled by a control circuit 24 consisting of a microcomputer, and the other water pump 23 is driven by the engine E.

The circulation path 20 is provided with a bypass passage 25 that passes through the radiator 21. This bypass passage 2
5 is used to help warm up the ennon by circulating cooling water without passing through the radiator 21 when the engine is in a cold state. □For this reason, the circulation passage 20 and
A thermostatic valve 26 is provided at a branch of the ξ space passage 25 to allow cooling water to flow into the bypass passage 25 until the engine is sufficiently warmed up.

A water temperature sensor 27 that detects the temperature of the cooling water in this portion is provided in the cylinder head water cannula 1a, and an output end of this water temperature sensor 27 is connected to one input end of the control circuit 24. There is. The blower switch 7 is connected to the other input terminal of the control circuit 24, and the control circuit 24 controls whether the heating device is turned on or off from the blower switch 7.
The changeover switch 12 and the opening/closing switch 13 are controlled in response to the signal S+ of F and the signal S2 indicating the cooling water temperature from the water temperature sensor 27.

Next, the operation of the heating device having the structure described above will be explained.

First, the operation of the heating system when the engine E is in a cold operating state will be explained. The blower switch 7 of the heating device is moved from OFF to the Low or Hl range, which is the ○N state, and the signal Sl indicating this and the water temperature sensor 27
When the empty signal s2 is input to the control device 24, the control circuit 24 sets the switching pulp 12 to a position that closes the bypass passage 11 and opens the opening/closing pulp 13. Since the temperature of the cooling water is low, the thermostatic valve 16 is opened so that the cooling water flows toward the circulation path 4 side. On the other hand, since the temperature of the cooling water is low, the thermostatic valve 26 is opened so that the cooling water flows into the bypass passage 25.

The control circuit 24 also receives a signal S from the blower switch 7.
, the first water pump 22 is driven to circulate cooling water into the circulation path 4.

The cooling water circulated in the circulation path 4 is heated by the cylinder head of the engine E in the cylinder head water cannula 1a. The cooling water heated by the cylinder head flows into the circulation path 4 from the outlet 3 and is further heated by the exhaust gas flowing through the exhaust passage 9 in the heat exchanger 10 .

This further heated cooling water is sent to the heater core 5.

The heater core 5 heats the air sent from the blower 6 and sends it into the vehicle interior to heat the vehicle interior. The cooling water that has passed through the heater core 5 is returned to the cylinder head water cannula 1a from the inlet 2 by the water pump 022. In this way, the cooling water is sufficiently heated by the relatively high-temperature cylinder head and the heat exchanger 10, so that a sufficient heating temperature can be obtained even when the engine E is at a low temperature.

When the rotational speed of Ennon E gradually increases and the water temperature sensor 27 detects that the temperature of the cooling water in the water cannula a of the cylinder head has exceeded a predetermined temperature, the control circuit 24 turns the changeover switch 12 on. Open the bypass passage 11 and open the exhaust passage 9.
The heat exchanger 10 side is set to be closed. Thus,
Heating of the cooling water by exhaust gas in the heat exchanger 10 is stopped to prevent overheating of the cooling water and Ennon. At this time,
As mentioned above, since the cooling water temperature is high, the thermostat pulp 16 also gradually transfers the cooling water to the bypass passage 1.
It is set to pass through on the 4th side. The cooling water flowing to the bypass passage 14 side is cooled in the radiator 15 and joins with the cooling water passing through the circulation path 4 to raise the temperature of the entire cooling water. Thus, from this point as well, the cooling water and the engine E
This prevents the cylinder head from overheating.

On the other hand, the first water pump 23 is driven by the engine E to circulate the cooling water to the circulation path 20, but as described above, when the engine E is cold, the thermostat valve 26 moves the cooling water to the pinos passage. Since the cooling water is set to flow through the radiator 25, the cooling water does not flow through the radiator 21 and therefore does not radiate heat, thus promoting warming up of the Ennon E. When the rotational speed of the engine E gradually increases and the temperature of the cooling water circulating in the circulation path 20 reaches a predetermined temperature or higher, the thermostat pulp 26 gradually opens so that the cooling water also flows into the radiator 21, thus cooling the engine. The water is cooled in the radiator 21 to prevent the cooling water and the cylinder block of the Ennon E from overheating.

In the above embodiment, the cooling water cannula 1 is connected to the cylinder head water cannula 1a and the cylinder block water cannula 1 from the partition wall PK.
In the above explanation, the cooling water mantle 1 is divided into the exhaust side and the intake side by the partition wall P, and the exhaust side is divided into the high temperature part 1a and the high temperature part 1a. ,
The intake side can also be the low temperature section 1b. Furthermore, for example, in a double cylinder ennon, the cooling water cannula 1 is divided into a central cylinder side and an outer cylinder side by partition walls P1 and P2, as shown in FIG. The outer cylinder side can be the low temperature section 1b.

In the above heating device, the first water pump 022
Basically, when the heating system is in operation, it is rotated at a constant rotation speed, and when the heating system is not in use, the rotation is set according to the temperature of the cooling water detected by the water temperature sensor 27, the engine load, the rotation speed, etc. Just do it like this. Further, during cranking, the walk pump 22 may be stopped to prevent deterioration of startability due to a decrease in rotation of the starter motor. For example, when the heating system is not in use, depending on the temperature of the cooling water, the water J? Water pump 022f: When controlling, the water pump 022 is operated at a constant low speed until the temperature of the cooling water detected by the water temperature sensor 27 reaches the first predetermined temperature T1, as shown in FIG. Then, the water pump 220 rotation speed is increased in accordance with the rise in the temperature of the cooling water until the temperature of the cooling water rises and reaches temperature T2. This prevents the engine from overheating and then allows it to run at a constant rotation speed. The case where the operation of the water pump 22 is controlled according to the cooling water temperature has been explained above, but even if the load increases, local overheating of the engine E may occur, so It is desirable to control the rotational speed of the water pump 7''22 according to the increase in the water pump 7''22.

Also, when starting the engine, that is, when cranking,
In order to prevent deterioration of startability due to a voltage drop caused by the operation of the water pump 22, it is desirable to temporarily stop the operation of the water pump 22 as described above. In order to perform the above control, it is necessary to provide an engine load sensor, an engine rotation speed sensor, and a cranking sensor in addition to the water temperature sensor 27, and input the output signals of these sensors to the control circuit. It is.

In the above embodiment, the operation of the water pump 22 is controlled by the control circuit 24 using a microcomputer, but this control may also be performed by an electric circuit as shown in FIG.

The electric circuit 31 shown in FIG. S is a drive control circuit for the water pump 22, and includes a differential amplifier 31 and a drive transistor 32 whose base is connected to the output terminal of the differential amplifier 31. The water temperature sensor 21 is connected to one input terminal of the differential amplifier 31, and the constant voltage generator 33 that generates a constant voltage Vr is connected to the other input terminal. .

The differential amplifier 31 uses the constant voltage r and the water temperature sensor 27.
detects the 6 m degree of cooling water in the cylinder head water jacket a and compares it with the output signal S2 to output a difference signal Sd2. When the cooling water temperature is T or higher, the l-transistor 32 operates the water pump 51 with a current according to this difference signal Sd2.
'f: The operation is controlled as shown in Fig. q. As described above, it is desirable that the pump 22 rotates at a constant low speed until the cooling water reaches the first predetermined temperature T1.
The pump 22 is also connected to a power source 34 which provides a constant low voltage. On the other hand, a switch 36 that interlocks with the blower switch 7 is interposed at the base of the transistor 32, so that when the heating system is activated (when the blower switch 7 is ON), regardless of the output of the water temperature sensor 27, l. Ranjisk 32
is turned ON, and the pump 22 is rotated at a predetermined constant rotation speed.

As a result of the above, the pump 22 is driven as a whole as shown in FIG. 51, there is a relay 35 that cuts off the operating circuit of the pump 22 when the starter St is turned on.
It is desirable to have a It is assumed that the water temperature sensor 27 outputs the signal S2 only when the cooling water temperature reaches a certain predetermined temperature (for example, T+) or higher. Therefore, the differential amplifier 31 does not output the difference signal Sd until the predetermined temperature is reached, and thus the pump 022 does not operate.

Further, in the above embodiment, the second water pump f23 has an engine-driven structure, but like the first water pump f23, it may be an electric pump controlled by a water temperature sensor or the like.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a heating device according to an embodiment of the present invention, FIG. 2 is a modification of the cooling water canister used in the heating device shown in FIG. 1, and FIG. 3 is a diagram similar to that shown in FIG. Another modified example of the cooling water canister used in the heating device shown in FIG. 7 is a graph showing an example of operation of the first motor pump, and FIG. FIG. 2 is a circuit diagram showing an example of an electric circuit. E ・Engine, 1...Cooling water mantle, 1a...
Silling head water jacket, 1b... Cylinder block water jacket, 4... Cooling water circulation passage for heating, 5... Heater core, 9... Exhaust passage, 10... Heat exchanger, 20... Lasoator cooling Water circulation passage, 22...first water pump, 23...th water pump. Patent applicant: Toyoko 1 Co., Ltd.

Claims (1)

[Claims] Cooling water is drawn out from the high-temperature part of the cooling water mantle of the Ennon body, and is cooled through a heat exchanger installed in the exhaust passage that heats the cooling water through heat exchange with exhaust gas, and a heater core for heating the vehicle interior. a first for returning water to the hot section of the cooling water cannula;
a first water ponzo provided in the first cooling water circulation path; and a first cooling water circulation path connecting a portion of the engine body other than the high temperature portion of the cooling water mantle to the lanoator. , and a first water pump 0 provided in the first cooling water circulation path.