JPH11115474A - Air heating system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recover or effectively utilize the braking energy which is wasted in a conventional one, as the energy to be used for air conditioning by providing a control means for adjusting the discharging capacity of a variable capacity compressor in response to the pedaling amount of an accelerator of an engine or in response to the ON/OFF of the accelerator. SOLUTION: When open degree of an accelerator is low or an accelerator is turned off, suction pressure operating point of a variable capacity compressor 12 is controlled high so as to raise the temperature of a condenser 7. Namely, discharging capacity is set larger than the discharging capacity to be required for achieving the target discharge temperature, and energy for warming is stored in the condenser 7 so as to heat the condenser 7. In the case where open degree of the accelerator is high and condenser outlet air temperature at the target discharge air temperature or more is detected, discharging capacity of the variable capacity compressor 12 is set at the lowest value, and opening and closing valves 18, 19 provided in an outlet and an inlet of the condenser 7 are closed. With this structure, heat capacity of the heated condenser 7 is effectively utilized as the heating energy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device for a vehicle, and more particularly to a heating device for a vehicle capable of automatically adjusting a heat radiation amount of a condenser constituting a part of a heat pump in accordance with operating conditions of the vehicle. .

[0002]

2. Description of the Related Art Automobiles frequently repeat acceleration and deceleration by turning the accelerator on and off, but the braking energy is increased by radiation from the brake discs and drums and an increase in the number of revolutions (fuel consumption) caused by the engine brake. It is discarded as almost 100% energy loss. Although fuel efficiency of automobiles is increasing, air conditioners for vehicles,
Particularly in connection with a vehicle heating device, further reduction in fuel consumption, that is, a study on energy saving of the vehicle heating device is likely to be required in the future.

[0003]

SUMMARY OF THE INVENTION The object of the present invention is to provide a braking energy which has conventionally been discarded while maintaining temperature control (heating) performance, in view of such energy saving which is likely to be required in the future. The aim is to recover or effectively use comparable energy as energy to be used for temperature control as a result, and to improve the performance of vehicle heating systems that use a refrigerant circuit as a heat pump and arrange a condenser in a ventilation duct. It is in.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a heating device for a vehicle according to the present invention includes a blower for sending air into a vehicle interior through a ventilation duct, and a condensing unit provided in the ventilation duct for heating the air. A heating device for a vehicle having a variable displacement compressor driven by a vehicle driving engine and capable of changing a discharge capacity for circulating a refrigerant to the condenser, wherein the accelerator is operated in accordance with an accelerator depression amount of the engine, or Control means for adjusting the displacement of the variable displacement compressor in accordance with the on / off state of the compressor.

[0005] The vehicle heating device preferably has a condenser air mix damper capable of adjusting the ratio of the flow rate of air flowing into the condenser to the flow rate of bypass air.

When the accelerator depression amount (accelerator opening) is equal to or smaller than a predetermined value or when the accelerator is off, the discharge capacity of the variable displacement compressor is adjusted to achieve a target discharge temperature. It is preferable to increase the capacity to a required value or more, and to adjust the discharge temperature to a target value by the condenser air mix damper. With this configuration, when the accelerator opening is equal to or less than a predetermined value or the accelerator is off and the engine is under a low load, the temperature of the condenser can be increased to accumulate heating energy.

If the temperature of the condenser is higher than the target discharge temperature when the accelerator is on, the on-off valve at the refrigerant inlet / outlet of the condenser is closed to minimize the discharge capacity of the variable displacement compressor. Preferably, the connection of the drive system of the variable displacement compressor is cut off. In this way, the heat capacity for heating stored in the condenser is effectively used, whereby a desired heating state is obtained, and energy for heating is saved.

If the temperature of the condenser is lower than the target discharge temperature when the accelerator is turned on, the on-off valve at the refrigerant inlet / outlet of the condenser is opened, and the variable valve is controlled so that the discharge temperature becomes the target value. Preferably, the displacement of the displacement compressor is adjusted. In this way, the heating heat capacity stored in the condenser is effectively used as described above, but it is necessary to obtain a desired heating state when the temperature of the condenser gradually decreases. Only minimal energy can be used.

That is, in the vehicle heating device according to the present invention, the energy at the time of braking or deceleration, which has been conventionally discarded, is stored as heating energy or is eventually recovered. It is effectively used as heating energy during acceleration. Therefore, the total amount of energy to be discarded is greatly reduced, and energy saving and, consequently, low fuel consumption of the vehicle are achieved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a vehicle heating device according to one embodiment of the present invention. In the drawing, reference numeral 1 denotes a ventilation duct for sending air (particularly, warm air in the present invention) whose temperature is adjusted into the vehicle interior. An outside air inlet 2 and an inside air inlet 3 are provided on the suction side of the ventilation duct 1. In addition, the intake ratio of the inside and outside air can be adjusted by the damper 4. The suction of the inside and outside air and the air pressure sending into the vehicle interior are performed by a blower 6 driven by a motor 5.

On the downstream side of the blower 6 in the ventilation duct 1,
A condenser 7 for heating the air is provided, and a condenser air mix damper 8 is provided in the condenser 7 so that a ratio of an air flow rate flowing into the condenser 7 to an air flow rate bypassing the condenser 7 is obtained. Can be adjusted. The opening degree of the condenser air mix damper 8 is adjusted by a condenser air mix damper actuator 9.

The refrigerant circulated in the refrigerant circuit 10 is sent to the condenser 7. The refrigerant circuit 10 is provided with a variable displacement compressor (variable displacement compressor) 12 driven by a vehicle drive engine 11 and capable of changing a discharge capacity. In the present embodiment, the variable displacement compressor 12 is provided with an appropriate driving force transmission mechanism and a clutch 13 by the engine 11.
, And the clutch 13 is controlled by a clutch controller 14. As the variable displacement compressor 12, one capable of arbitrarily adjusting the discharge displacement according to an external signal is used. This variable capacity compressor 12
Thereby, the refrigerant is circulated to the condenser 7.

The refrigerant circuit 10 includes an evaporator 15 and an expansion valve 1
6. A reservoir tank 17 is provided, and on / off ports of the condenser 7 are provided with opening / closing valves 18 and 19 formed of electromagnetic valves. The refrigerant is circulated in the circuit 10 in the direction of the arrow.

A condenser outlet air temperature sensor 20 is provided immediately downstream of the condenser 7 in the ventilation duct 1.
On the downstream side, there are dampers 24, 2, which regulate the air blown out from the air outlets 21, 22, 23 and the air outlets from the air outlets.
5 and 26 are provided.

Reference numeral 30 denotes a main controller as control means for the present air conditioner. An in-vehicle temperature setting device 31 is connected to the main controller 30 to set a target in-vehicle temperature to be controlled. Also,
A signal from the condenser outlet air temperature sensor 20, a signal from the vehicle interior temperature sensor 32,
In addition to the signal from the solar radiation sensor 33 and the signal from the outside air temperature sensor 34, a signal from an accelerator sensor 35 and a signal from a vehicle speed sensor 36 are input. The accelerator sensor 35 is
An accelerator depression amount (accelerator opening) and an accelerator on / off signal are issued. further,
The signal from the main controller 30 is sent to the motor 5 of the blower 6, the condenser air mix damper actuator 9, the discharge displacement variable means of the variable displacement compressor 12, for example, the suction pressure controller, and the clutch controller 14.

[0016] The heating device for a vehicle configured as described above includes:
The control is performed as shown in FIG. The vehicle speed and the accelerator opening are detected, and when the accelerator opening is a1 or less (including accelerator off) (regions 101 and 103 in FIG. 2), the discharge capacity of the variable displacement compressor 12 is controlled to be high, Increase the temperature. That is, when the amount of depression of the accelerator is small, or when the accelerator is off, the discharge capacity is increased to be larger than the discharge capacity required to achieve the target discharge temperature, and energy for heating is stored in the condenser 7 to condense. The vessel 7 is heated.

At this time, although the condenser outlet air temperature rises, the opening degree of the condenser air mix damper 8 is calculated as described below, and the exhaust gas temperature is adjusted to the target value. AMD = (TV−T _in ) / (T _c −T _in ) Here, in the case of inside air circulation: T _in = T _r , and _in the case of outside air introduction: T _in = T _am . AMD: condenser air mix damper opening TV: target nausea temperature T _in: intake air temperature T _c: the condenser outlet air temperature T _r: the passenger compartment temperature T _am: outside air temperature

When the accelerator opening is equal to or higher than a1 and the condenser outlet air temperature is equal to or higher than the target discharge temperature TV, the discharge capacity of the variable displacement compressor 12 is set to a minimum (for example, o
cc / rev), an on-off valve 1 provided at the entrance and exit of the condenser 7
8 and 19 (electromagnetic valves) are closed (regions 102 and 1 in FIG. 2).
04). As a result, the heat capacity of the condenser 7 that has been heated up to that time is effectively used as heating energy. In the above description, instead of minimizing the discharge capacity, the clutch 13 may be turned off and the drive system of the variable displacement compressor 12 may be shut off.

As described above, while the energy for heating stored in the condenser 7 is being effectively used, the condenser 7
When the accelerator opening degree is equal to or more than a1 and the condenser outlet air temperature is equal to or lower than the target discharge temperature TV, the on-off valve 1
8 and 19, the condenser outlet air temperature becomes equal to the target exhaust temperature T
The discharge capacity of the variable displacement compressor 12 is adjusted by the following equation so as to obtain V (region 105 in FIG. 2). Q _c = -P + I, _{however, P = k p (TV-} T c) ··· proportional term _{I = I n-1 -k i} (TV-T c) ··· integral term Q _c: compressor discharge capacity T _c: condenser outlet air temperature TV: target nausea temperature k _p, k _i: coefficient

As described above, the discharge capacity of the variable displacement compressor 12 is automatically adjusted according to the operating conditions of the vehicle (opening degree of the accelerator) and the temperature condition at that time, and is conventionally simply discarded at the time of deceleration or braking. The used energy is effectively used as heating energy.

[0021]

As described above, according to the vehicle heating apparatus of the present invention, the energy at the time of deceleration or control, which was conventionally discarded, can be effectively used as heating energy. Therefore, in connection with the heating device for a vehicle, energy saving and, in turn, low fuel consumption of the vehicle can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a vehicle heating device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between each characteristic and time, showing a control example of the apparatus in FIG. 1;

[Description of Signs] 1 Ventilation duct 5 Motor 6 Blower 7 Condenser 8 Condenser air mix damper 9 Condenser air mix damper actuator 10 Refrigerant circuit 11 Engine 12 Variable capacity compressor 13 Clutch 14 Clutch controller 18, 19 Open / close valve 20 Condenser Outlet air temperature sensor 21, 22, 23 Outlet 30 Main controller 31 In-vehicle temperature setting device 32 In-vehicle temperature sensor 33 Solar radiation sensor 34 Outside air temperature sensor 35 Accelerator sensor 36 Vehicle speed sensor

Claims (5)

[Claims] 1. A blower for sending air into a vehicle interior through a ventilation duct, a condenser provided in the ventilation duct to heat air, and a discharge capacity driven by a vehicle driving engine to circulate refrigerant through the condenser. A heating device for a vehicle having a possible variable displacement compressor, wherein the control means adjusts the displacement of the variable displacement compressor according to an accelerator pedal depression amount of the engine or on / off of an accelerator. A heating device for a vehicle, comprising: 2. The vehicle heating apparatus according to claim 1, further comprising a condenser air mix damper capable of adjusting a ratio between an air flow rate flowing into the condenser and an air flow rate bypassing the condenser. 3. When the accelerator depression amount is equal to or less than a predetermined value, or when the accelerator is off, the discharge capacity of the variable displacement compressor is set to be higher than the capacity required to achieve a target discharge temperature. Adjust the exhaust gas temperature to the target value with the condenser air mix damper,
The heating device for a vehicle according to claim 2. 4. When the temperature of the condenser is higher than a target discharge temperature when the accelerator is on, the on-off valve at the refrigerant inlet / outlet of the condenser is closed to minimize the discharge capacity of the variable displacement compressor. The heating device for a vehicle according to any one of claims 1 to 3, wherein the heating device is configured to disconnect the drive system of the variable displacement compressor. 5. When the temperature of the condenser is lower than a target discharge temperature when the accelerator is turned on, an on-off valve at a refrigerant inlet / outlet of the condenser is opened, and the variable temperature is adjusted so that the discharge temperature becomes a target value. The vehicle heating device according to any one of claims 1 to 4, wherein the displacement of the displacement compressor is adjusted.