JPH0550844A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To prevent acceleration performance from being impeded at the time of starting a vehicle by controlling a capacity of a compressor for a predetermined time at a predetermined capacity control rate when a high pressure in a high pressure side refrigerant circuit is increased to a predetermined value or more. CONSTITUTION:A refrigerant pressure reaching an expansion valve from a compressor is detected by a high pressure sensor 47, and this signal is compared with a signal from a setting means 62 by a comparator means 61 and input to a capacity determining means 63. In this capacity determining means 63, a capacity of the compressor 28 is determined based on a control map and rule from a memory means 64 and input to a timer 65 while to a capacity controller of the compressor 28, and its capacity is decreased to serve as a determined capacity control rate. Accordingly, decrease of acceleration performance of an engine for running can be avoided at accelerating operation time or the like of a vehicle in the summer season.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner.

[0002]

2. Description of the Related Art As shown in FIG. 4, an inside air inlet 13 and an outside air inlet 14 are formed on the upstream side of a casing 12 of an air conditioner 10, and a face outlet 20 and a defrost outlet are provided on the downstream side. 23 and a foot outlet 24 are formed. The inside air suction port 13 and the outside air suction port 14 are switched by an inside air / outside air switching damper 15. Face outlet 20, Defrost outlet 23
And the foot outlet 24 are respectively blowout mode switching dampers 2
It is opened and closed by 5, 26 and 27. Inside the casing 12, a blower 16, an evaporator 17, an air mix damper 18, and a heater 19 are arranged. The evaporator 17 constitutes a refrigerant circulation circuit by being connected to a compressor 28, a condenser 29, a receiver 30, an expansion valve 31 and the like via a refrigerant pipe.
The compressor 28 is driven by the traveling engine 35 via the pulley 33 and the magnet clutch 34, and is provided with a capacity control device that controls the amount of displacement by input of an external signal. The cooling water for the running engine 35 circulates in the heater 19,
The air volume passing through 19 is changed by the opening degree of the air mix damper 18.

When the blower 16 is driven, an inside / outside air switching damper
The inside air or the outside air from the inside air intake port 13 or the outside air intake port 14 selected by switching 15 is supplied to the casing 12
After being sucked in and energized by a blower 16, it is cooled by passing through an evaporator 17. Then
This air is diverted by the air mix damper 18, a part of which is heated by passing through the heater 19 and then mixed with the remaining air bypassing the heater 19 to become conditioned air of a predetermined temperature. Then, this conditioned air is blown into the vehicle interior from any one or two of the face outlet 20, the defrost outlet 23, and the foot outlet 24 selected by opening and closing the blowout mode switching dampers 25, 26, 27. ..

Reference numeral 11 is a control device composed of a microcomputer, which has an I / O port, a multiplexer, an A / D converter, a central processing unit CPU, a read-only memory ROM, a random access memory RAM and the like. The detected values of the potentiometer 41 that detects the opening degree of the air mix damper 18, the solar radiation sensor 42, the outside air temperature sensor 43, the room temperature sensor 44, the temperature sensor 45 of the cool air blown from the evaporator 17, and the like are input to the control device 11. In addition, a control panel installed in front of the driver's seat
46 is an operation switch of the air conditioner 10, a changeover switch of the blowout mode, a changeover switch of the inside / outside air changeover damper 15, a cooling operation switch for setting the cooling operation, an air volume changeover switch for changing the rotation speed of the blower 16, and an automatic air conditioning control. Control
An AUTO switch, a temperature setting device for arbitrarily setting the temperature inside the vehicle, and the like are provided, and the outputs of these are also input to the control device 11. The output of the control device 11 is sent to the compressor 28 and the magnet clutch 3 via a driver (not shown).
4. The blower 16 and the dampers 15, 18, 25, 26, 27 are sent to the motor actuators 56, 57, 58 and the like to control their operation.

[0005]

[Problems to be Solved by the Invention] When a vehicle is driving in an urban area,
Starting and stopping are repeated, and immediately after the vehicle starts moving, the rotational speed of the running engine 35 rapidly rises, and along with this, the compressor
28 rpm increases. Then, the refrigerant circulation amount increases,
As the high pressure in the high pressure side refrigerant circuit increases, the low pressure decreases and the compression ratio of the compressor 28 increases. As a result,
There is a problem that the acceleration performance of the vehicle is impaired because not only the efficiency of the compressor 28 decreases but also the power consumption thereof increases.

[0006]

SUMMARY OF THE INVENTION The present invention has been invented to solve the above problems, and the gist of the first invention is that a capacitor for controlling the amount of displacement by inputting an external signal. In a vehicle air conditioner equipped with a compressor with a control device, a high pressure sensor for detecting the high pressure in the high pressure side refrigerant circuit is provided, and when the high pressure detected by this sensor exceeds a predetermined pressure, The air conditioner for a vehicle is provided with a control means for setting the capacity of the compressor to a predetermined capacity control rate for a predetermined time.

A rotational speed detection sensor for the traveling engine for driving the compressor is provided, the engine rotational speed detected by this sensor is equal to or higher than a predetermined rotational speed, and the high pressure detected by the high pressure sensor is predetermined. When the pressure becomes equal to or higher than the pressure, the capacity of the compressor can be set to a predetermined capacity control rate for a predetermined time by the control means.

The gist of the second invention is that in a vehicle air conditioner equipped with a compressor with a capacity control device for controlling the displacement by the input of an external signal, a running engine for driving the compressor. A rotation speed detection sensor and an outside air temperature sensor are provided, the outside air temperature detected by the outside air temperature sensor is equal to or higher than a predetermined temperature, and the engine rotation speed detected by the rotation speed detection sensor is equal to or more than a predetermined rotation speed. At this time, there is provided a vehicle air conditioner characterized by comprising control means for setting the capacity of the compressor to a predetermined capacity control rate for a predetermined time.

[0009]

In the first aspect of the present invention, when the high pressure in the high pressure side refrigerant circuit becomes equal to or higher than a predetermined pressure, or this high pressure is equal to or higher than a predetermined pressure and the engine speed becomes equal to or higher than a predetermined speed. At this time, the capacity of the compressor becomes a predetermined capacity control rate for a predetermined time. In the second invention, when the outside air temperature is equal to or higher than the predetermined temperature and the engine speed is equal to or higher than the predetermined speed, the capacity of the compressor is a predetermined capacity control rate for a predetermined time.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENT One embodiment of the present invention is shown in FIG. High pressure in the high pressure side refrigerant circuit, that is, from the compressor 28 to the expansion valve
The high-pressure pressure detected by the high-pressure pressure sensor 47 that detects the pressure of the refrigerant in the refrigerant circuit up to 31 is input to the comparison means 61, where it is compared with the preset pressure set in the setting means 62. The comparison result is input to the capacity determination means 63, and the capacity of the compressor 28 is determined based on the control map and the control rule input from the storage means 64. The result of this determination is input to the timer 65 at the same time as it is input to the capacity control device of the compressor 28, and the capacity control device reduces the displacement amount of the compressor 28, and the capacity of the compressor 28 is reduced and determined. It is a capacity control rate.

When the determination result is input, the timer 65 starts counting and outputs a message to that effect to the capacity determining means 63 when a preset time has elapsed. Then, the capacity determining means 64 determines to restore the original capacity, and thereafter, the compressor 28 is operated at the original capacity control rate. Thus, when the high pressure becomes equal to or higher than the predetermined pressure, the capacity of the compressor 28 is reduced to the predetermined capacity control rate for the predetermined time, and the power consumption of the compressor 28 is decreased for the predetermined time. Other configurations and operations are similar to those of the conventional one shown in FIG.

FIG. 2 shows a second embodiment of the present invention. The rotation speed detected by the engine rotation speed sensor 48 that detects the rotation speed of the traveling engine 35 that drives the compressor 28 is input to the comparison means 66, where the setting rotation speed preset in the setting means 67 and The comparison is made and the comparison result is inputted to the capacity determining means 63. The capacity determining means 63 determines that the capacity of the compressor 28 should be reduced when the high pressure is equal to or higher than a predetermined pressure and the engine speed is equal to or higher than a predetermined speed.
The other structure is similar to that of the first embodiment shown in FIG. In the second embodiment, when the high pressure is equal to or higher than a predetermined pressure and the engine speed is equal to or higher than a predetermined speed, the capacity of the compressor 28 is reduced to a predetermined capacity control rate for a predetermined time. Therefore, the load at the time of acceleration of the traveling engine 35 can be reduced and the deterioration of acceleration performance can be efficiently avoided.

FIG. 3 shows a third embodiment of the present invention. The outside air temperature detected by the outside air temperature sensor 49 for detecting the outside air temperature is input to the comparison means 68, and here the setting means 69 is set.
Is compared with a preset temperature set in advance, and the comparison result is input to the capacity determining means 63. The capacity determining means 63 determines to reduce the capacity of the compressor 28 when the outside air temperature is equal to or higher than a predetermined temperature and the engine speed is equal to or higher than a predetermined speed. Other configurations and operations are similar to those of the second embodiment shown in FIG. In the third embodiment, when the outside air temperature is equal to or higher than a predetermined temperature and the engine speed is higher than or equal to a predetermined speed, the capacity of the compressor 28 is reduced to a predetermined capacity control rate for a predetermined time. Therefore, it is possible to reduce the load at the time of engine acceleration and avoid the deterioration of the acceleration performance.

[0013]

According to the present invention, the capacity of the compressor is reduced to a predetermined capacity control ratio for a predetermined time during acceleration operation of the vehicle in summer, so that deterioration of the acceleration performance of the running engine can be avoided.

[Brief description of drawings]

FIG. 1 is a control block diagram showing a first embodiment of the present invention.

FIG. 2 is a control block diagram showing a second embodiment of the present invention.

FIG. 3 is a control block diagram showing a third embodiment of the present invention.

FIG. 4 is a system diagram of a conventional vehicle air conditioner.

[Explanation of symbols]

 28 Compressor with capacity controller 47 High pressure sensor 61 Comparison means 62 Setting means 63 Capacity determination means 64 Storage means 65 Timer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Terauchi Kenichi Terauchi 3-chome, Asahimachi, Nishibiwajima-cho, Nishikasugai-gun, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Air Conditioning Factory

Claims (3)

[Claims] 1. An air conditioner for a vehicle, comprising a compressor with a displacement control device for controlling a displacement amount by inputting an external signal, and a high pressure sensor for detecting a high pressure in a high pressure side refrigerant circuit, and An air conditioner for a vehicle, comprising: a control means for setting the capacity of the compressor to a predetermined capacity control rate for a predetermined time when the high pressure detected by the sensor exceeds a predetermined pressure. 2. A rotational speed detection sensor for a traveling engine that drives the compressor is provided, the engine rotational speed detected by the sensor is equal to or higher than a predetermined rotational speed, and the high pressure detected by the high pressure sensor. 2. The vehicle air conditioner according to claim 1, wherein when the pressure exceeds a predetermined pressure, the control means sets the capacity of the compressor to a predetermined capacity control rate for a predetermined time. 3. An air conditioner for a vehicle, comprising a compressor with a displacement control device for controlling the amount of displacement by inputting an external signal, in a vehicular air conditioner, a rotational speed detection sensor and an outside air temperature sensor of a running engine for driving the compressor. When the outside air temperature detected by the outside air temperature sensor is equal to or higher than a predetermined temperature and the engine speed detected by the rotation speed detection sensor is equal to or higher than a predetermined rotation speed, the capacity of the compressor is set to a predetermined value. A vehicle air conditioner characterized in that it is provided with control means for maintaining a predetermined capacity control rate for a certain period of time.