JP2744488B2 - Automotive heating system using exhaust heat - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) An automotive heating device using exhaust heat according to the present invention uses the heat pipe principle to generate heat from exhaust gas discharged from an engine. It heats the room.

(Conventional technology) In the case of a heating device that heats the interior of a vehicle using exhaust heat, the heating device starts up faster than a device that heats the heat of cooling water (the time required until a feeling of heating is obtained). Is short), and in cold regions, etc., even if it is not possible to obtain a sufficient feeling of heating just by using the heat of cooling water, this can be sufficiently assisted. Things are being studied. Among these, as a heating device for an automobile that collects exhaust heat by using the principle of a heat pipe and heats the interior of a vehicle, a heating device disclosed in Japanese Utility Model Application Laid-Open No. 63-114806 and the like has been known. .

Such a heating apparatus for an automobile using the exhaust heat, which utilizes the principle of the heat pipe, is configured, for example, as shown in FIG.

In FIG. 3, reference numeral 1 denotes an exhaust pipe through which exhaust gas discharged from the automobile engine 2 flows. In the exhaust pipe 1, first and second exhaust passages 3 and 4 are connected to each other. They are provided in parallel. A heater 5 for heating and evaporating a working fluid such as pure water is provided in the first exhaust passage 3, and one end of a steam delivery pipe 6 is connected to a steam outlet of the heater 5. Connected.

In the middle of the exhaust pipe 1, the first and second exhaust passages 3, 4
An exhaust passage switching door 7 for controlling the sending of exhaust gas to the first exhaust passage 3 in which the heater 5 is disposed and the stop thereof is provided on the upstream side of the heater 5. The amount of heating can be adjusted freely.

On the other hand, a condenser 10 is arranged in series with a heater core 9 for circulating hot water (engine cooling water) in a duct through which air for heating is circulated by the blower 8.
The steam inlet of the condenser 10 is connected to the steam delivery pipe 6
The other end of the condenser 10 has one end connected to the outlet of the condenser 10 and a return pipe 13 provided with a reservoir 11 and a gate valve 12 on the way.
Is connected to the heater 5 through a part of the steam delivery pipe 6 so that the working fluid condensed and liquefied in the condenser 10 is returned to the heater 5.

14 is an actuator for driving the exhaust passage switching door 7,
15 is a safety valve provided in the middle of the steam delivery pipe 6, and 16 is
Sent through the steam delivery pipe 6 to the condenser 10;
A temperature sensor for detecting the temperature of the steam, 17 is a temperature sensor for detecting the temperature at the top of the condenser 10, 18 is a temperature sensor for detecting the temperature of the hot water fed into the heater core 9, and 19 is A temperature sensor 24 for detecting the temperature of the air after passing through the heater core 9 and the condenser 10,
To discharge air mixed in the working fluid, a condenser 10
A solenoid on-off valve 25 provided at the top of the valve is a relief valve provided in series with the solenoid on-off valve.

A controller (not shown) for controlling the switching of the exhaust passage switching door 7 and the opening and closing of the gate valve 12 is provided by an exhaust passage switching door in accordance with signals from the temperature sensors 16 to 19. 7
And the gate valve 12 is opened and closed.

When the interior of the vehicle is heated by the conventional heating device for an automobile using the exhaust heat configured as described above, the exhaust passage switching door 7 is switched as shown by a chain line in FIG. 12 is opened and the blower 8 is operated.

As a result, the working fluid present in the heater 5 evaporates,
The steam is sent to the condenser 10 through the steam delivery pipe 6. The working fluid vapor in the condenser 10 is
The air is sucked into a duct (not shown) by the blower 8, condenses by performing heat exchange with air flowing through the duct, and is returned to the return pipe 13, the reservoir 11, the gate valve 12, and the steam delivery pipe 6. A cycle of returning to the heater 5 through a part of the evaporator and evaporating again is repeated. The air whose temperature has increased due to heat exchange in the duct is blown into a vehicle interior from a suitable outlet provided at a downstream end of the duct, and is used for heating the vehicle interior.

When the heating device is not used, or when heating by the heater core 9 is sufficient, the exhaust passage switching door 7 is switched to the state shown by the solid line in FIG. 3 and the gate valve 12 is closed.

As a result, the high-temperature exhaust gas is not sent to the heater 5 and the working fluid is not sent to the heater 5 while the working fluid is stored in the reservoir 11, so that the temperature of the condenser 10 rises. Therefore, the temperature of the air flowing through the duct does not rise excessively.

(Problems to be Solved by the Invention) By the way, when a vehicle heating device utilizing exhaust heat and configured and operating as described above is incorporated in an actual vehicle heating device, the following problems must be solved. There are issues that must be addressed.

That is, pure water may be used as the working fluid to be evaporated by the heater 5 and condensed by the condenser 10. However, when pure water is used, the working fluid in the state where the working fluid is stored in the reservoir 11 is considered. If the working fluid is left as it is (the engine is stopped), the working fluid may freeze in the reservoir 11.

In other words, in the case of a heating device that uses exhaust heat, as described above, the start-up time is faster than that of a device that uses heating of cooling water, and even when sufficient heating cannot be performed with the heat of cooling water. Although it is possible to make up for the insufficient amount, but it is not always possible to obtain a stable heating capacity, the condenser 10 and the heater core 9 are arranged in series, and in the initial stage heating using exhaust heat is performed. After the temperature of the cooling water rises, it is conceivable to perform heating by the heater core 9 for flowing the cooling water. When such a mechanism is employed, the working fluid may remain stored in the reservoir 11 even when the temperature is low enough to require heating. Further, even when the vehicle is stopped while heating using the exhaust heat, a large part of the working fluid remains stored in the reservoir 11 with the closing of the gate valve 12. Becomes

As described above, when the working fluid is stored in the reservoir 1 when the working fluid is frozen in the reservoir 11 when the temperature is low (the temperature may drop below freezing), the working fluid is frozen. It becomes difficult to melt, and it becomes impossible to perform heating using exhaust heat.

The heating device for an automobile using the exhaust heat according to the present invention solves the above-mentioned disadvantages.

(Means for Solving the Problems) The vehicle heating device using the exhaust heat of the present invention is discharged from the vehicle engine in the same manner as the above-described conventional vehicle heating device using the exhaust heat. A heater provided in the middle of an exhaust pipe through which exhaust gas flows, a steam delivery pipe having one end connected to a steam outlet of the heater, and a duct arranged to flow heating air, and the steam inlet is provided with the steam A condenser connected to the other end of the delivery pipe, one end connected to the outlet of the condenser, and a return pipe for returning the working fluid condensed and liquefied in the condenser to the heater; And a gate valve provided in this order.

Further, in the automotive heating device utilizing the exhaust heat of the present invention, a heating jacket provided adjacent to the liquid reservoir, and a branch from the middle of the steam delivery pipe, and steam is supplied to the heating jacket. A branch feed pipe that can be fed freely, a discharge pipe for returning the working fluid from the heating jacket to the heater, and steam sent from the heater,
Switching means for selectively flowing the condenser and the heating jacket; a sensor for detecting a state of the working fluid in the reservoir; and switching of the switching means based on a signal from the sensor. When the working fluid in the reservoir is frozen, steam is fed into the heating jacket, and when the heating device is stopped, the gate valve is controlled to heat a part of the working fluid in the reservoir. And a controller that can be fed into the vessel.

(Operation) In the vehicle heating device using the exhaust heat of the present invention, which is configured as described above, the gate valve opens for a short time based on a signal from the controller when the operation is stopped, and the inside of the reservoir is opened. A part of the working fluid is sent to the heater.

At the start of the operation of the heating device, if it is determined that the working fluid in the reservoir is frozen based on a signal from a sensor attached to the reservoir, the controller sends the working fluid out of the heater. The switching means is switched in a direction in which the discharged steam flows into the heating jacket.

As a result, high-temperature steam generated by evaporating a part of the working fluid present in the heater is sent to a heating jacket provided adjacent to the liquid storage device, and stored through the heating jacket. Warm the remaining working fluid stored in the liquid container.

As a result, the working fluid frozen in the reservoir is melted in a short time, and is sent into the heater through the return pipe. The working fluid sent into the heater evaporates in the heater, is sent into the heating jacket, and further warms the working fluid remaining in the reservoir.

If it is determined from the signal from the sensor that the working fluid in the reservoir has been sufficiently melted, the switching means cuts the steam discharged from the heater in a direction to feed into the condenser based on the signal from the controller. Instead, it warms the air passing through the condenser, as in a conventional heating device.

Conversely, if it is determined based on the signal from the sensor attached to the reservoir that the working fluid in the reservoir is not frozen, the controller switches the switching means from the beginning of the operation of the heating device. Is switched to the direction in which the steam sent from the heater is sent to the condenser, and the air passing through the condenser is warmed in the same manner as in a conventional heating device.

(Example) Next, the present invention will be described in more detail while describing the illustrated example.

FIG. 1 is a partial schematic cross-sectional view showing a main part of a vehicle heating device using exhaust heat according to the present invention, and FIG. 2 is a flowchart showing the operation of this device.

The basic structure of the vehicle heating system using the exhaust heat of the present invention is the same as that of the vehicle heating system shown in FIG. 3 described above. The features will be described.

This reservoir 11 is provided between the heater 5 and the condenser 10 (see FIG. 3), and is provided below the reservoir 11 for temporarily storing the working fluid condensed in the condenser 10. The heating jacket 20 is provided so as to contact the lower surface of the heating jacket.

One end of this heating jacket 20, which has a steam flow path for heating inside, is connected to the end of a branch feed pipe 21 branched from a portion close to the condenser 10 in the middle of the steam feed pipe 6 to form a steam feed pipe. From 6 into the heating jacket 20,
The steam for heating can be sent freely.

A discharge pipe 22 for returning steam from the heating jacket 20 to the steam delivery pipe 6 is connected to the other end of the heating jacket 20, and the temperature of the heating jacket 20 is reduced by passing through a steam flow path in the heating jacket 20. The lowered steam can be returned to the heater 5 through the steam delivery pipe 6.

On the other hand, a switching door 23 as switching means is provided in the middle of the steam delivery pipe 6 inside the branch portion of the branch delivery pipe 21 so that the steam delivered from the heater 5 is supplied to the condenser 10 and the condenser 10. The heating jacket 20 can be selectively fed.

The reservoir 11 is provided with a sensor (not shown) such as a temperature sensor so that the state of the working fluid in the reservoir 11, that is, whether or not the working fluid is frozen, can be freely detected. The detection signal is also input to a controller (not shown).

The controller switches the switching door 23 as the switching means based on a signal from the sensor, and is provided between the liquid reservoir 11 and the heater 5 when the heating device is stopped. By controlling the gate valve 12, a part of the working fluid in the reservoir 11 can be sent to the heater 5.

The vehicle heating apparatus utilizing the exhaust heat of the present invention configured as described above operates as shown in the flowchart of FIG.

First, when the operation of the heating device is stopped, a part of the working fluid in the reservoir 11 is sent to the heater 5 based on a signal from the controller.

That is, when the heating device is stopped, in the conventional vehicle heating device, since the gate valve 12 is closed immediately, all the working fluid condensed in the condenser 10 is stored in the liquid reservoir 11, In the case of the heating device of the present invention, the gate valve 12 remains open for a short time after the heating device is stopped, and a part of the working fluid is sent to the heater 5.

Then, when the operation of the heating device is started (at the time of re-use), it is determined based on a signal from a sensor attached to the reservoir 11 that the working fluid in the reservoir 11 is determined to be frozen (for example, temperature When the temperature in the reservoir 11 detected by the sensor is 0 ° C. or lower), the controller causes the switching door 23 to change the steam discharged from the heater 5 into a heating jacket as shown by a solid line in FIG. Switch to the direction to flow to 20. In addition, the gate valve 12 that has been closed is opened based on the signal of the start of use.

As a result, high-temperature steam generated by evaporating a part of the working fluid present in the heater 5 is sent into the heating jacket 20 provided in contact with the lower surface of the liquid reservoir 11, and this heating is performed. Through the jacket 20, the remaining working fluid stored in the reservoir 11 is warmed.

As a result, the working fluid frozen in the reservoir 11 is melted in a short time, and from the melted portion, is sent to the heater 5 one after another through the return pipe 13, and is heated and evaporated in the heater 5, The working fluid sent into the heating jacket 20 and remaining in the liquid reservoir 11 is further melted.

When it is determined from the signal from the sensor attached to the reservoir 11 that the working fluid in the reservoir 11 has been sufficiently melted, the switching door 23 is opened based on the signal from the controller.
The switching is performed as shown by a chain line in the figure, and the steam sent from the heater 5 is sent to the condenser 10, and thereafter, the air passing through the condenser 10 is warmed in the same manner as a conventional automobile heating device using exhaust heat. .

Conversely, at the start of use, if it is determined based on the signal from the sensor attached to the reservoir 11 that the working fluid in the reservoir 11 is not frozen, the controller controls the heating device. From the beginning of the operation, the switching door 23 is switched to the state shown by the chain line in FIG. 1, and the steam sent from the heater 5 is sent from the beginning to the condenser 10, and passes through the condenser 10 in the same manner as the conventional heating device. To warm the air.

(Effect of the Invention) The automotive heating device using the exhaust heat of the present invention is configured and operates as described above. However, even if the working fluid freezes in the reservoir during cold weather, Since the working fluid inside can be melted in a short time, the heating can be performed in a short time after the engine is started, and the heating effect by the exhaust heat can be effectively used.

[Brief description of the drawings]

FIG. 1 is a partial schematic cross-sectional view showing a heating device for an automobile using the exhaust heat of the present invention, FIG. 2 is a flowchart showing the operation of the heating device, and FIG. 1 is a cross-sectional view illustrating an example of a heating device for an automobile. 1: Exhaust pipe, 2: Automotive engine, 3: First exhaust passage, 4:
Second exhaust passage, 5: heater, 6: steam delivery pipe, 7: exhaust passage switching door, 8: blower, 9: heater core, 10: condenser, 11: liquid reservoir, 12: gate valve, 13 : Return pipe, 14: Actuator, 15: Safety valve, 16, 17, 18, 19: Temperature sensor, 20: Heating jacket, 21: Branch feed pipe, 22: Discharge pipe, 23: Switching door, 24: Solenoid on / off valve, 25: Relief valve.

Claims (1)

(57) [Claims] 1. A heater provided in the middle of an exhaust pipe through which exhaust gas discharged from an automobile engine flows, a steam delivery pipe having one end connected to a steam outlet of the heater, and air for heating. A condenser having a vapor inlet connected to the other end of the vapor delivery pipe and a condenser connected at one end to an outlet of the condenser, for returning the working fluid condensed and liquefied in the condenser to the heater. And in the middle of this return pipe, in a vehicle heating device using exhaust heat, comprising a reservoir and a gate valve provided in order from the condenser side, provided adjacent to the reservoir. A heating jacket, a branch feed pipe that branches off from the middle of the steam delivery pipe and is capable of sending steam to the heating jacket, and an exhaust pipe for returning working fluid from the heating jacket to the heater. A pipe, switching means for selectively flowing steam sent from the heater to the condenser and the heating jacket, a sensor for detecting a state of a working fluid in the reservoir, The switching means is switched based on a signal from a sensor, and when the working fluid in the reservoir is frozen, steam is sent into the heating jacket, and when the heating device is stopped, the gate valve is controlled. A controller for enabling a part of the working fluid in the liquid reservoir to be sent to the heater, wherein the controller uses the exhaust heat.