Air Conditioning System (for Manual Air Conditioning System)
AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Manual Air Conditioning System): SYSTEM DIAGRAM
Communication table
SYSTEM DESCRIPTION
1. GENERAL
(a) The air conditioning system has the following features:
* Based on the signals from the ambient temperature sensor, this system calculates the outside temperature and indicates it in the multi-information display.
* The air conditioning amplifier calculates the target speed of the compressor based on the target evaporator temperature and the actual evaporator temperature sensor in order to control the compressor speed.
* This system turns the rear defogger and outside rear mirror heaters on for 15 minutes when the rear defogger switch is pressed and turns them off if the switch is pressed while they are operating.
* When a high load is applied to the EPS system, the EPS ECU will send a signal to the air conditioning amplifier. After receiving the signal, the air conditioning amplifier may turn off the rear defogger, front deicer, and seat heaters.
2. MODE POSITION AND DAMPER OPERATION
3. AIR OUTLET AND AIRFLOW VOLUME
HINT
* -: Not applicable
* The size of the circle o indicates the proportion of airflow volume.
HINT
* The size of the circle o indicates the proportion of airflow volume.
* -: Not applicable
4. Air Conditioning Control Assembly
(a) For both the front and rear manual air conditioning, the blower motor speed is steplessly adjustable. Pulse type control is used.
(b) The multi-information display is used as the manual air conditioning display.
5. Air Conditioning Unit
(a) Front Air Conditioning Unit
(1) The front air conditioning unit consists of the evaporator, heater core, servo motors, evaporator temperature sensor, and blower with fan motor sub-assembly.
* The evaporator and heater core are mounted transversely.
* Bus type communication is used between the servo motors and the air conditioning amplifier.
(b) Rear Air Conditioning Unit
(1) The rear air conditioning unit consists of the evaporator, heater core, servo motors, evaporator temperature sensor, and rear blower motor.
* The evaporator and heater core are arranged horizontally.
* The No. 2 air mix damper servo sub-assembly operates the laminate sliding type mode control door, and the rear air mix damper servo sub-assembly controls the full air mix type air mix doors.
* Bus type communication is used between the servo motors and the air conditioning amplifier.
(c) Evaporator
(1) For the evaporator, placing the tanks at the top and the bottom and adopting a micropore tube construction have realized the following effects.
* The heat exchange efficiency is improved.
* The temperature distribution is made more uniform.
* The evaporator is made thinner.
(d) Evaporator Temperature Sensor
(1) The evaporator temperature sensors (No. 1 cooler thermistor for the front air conditioning unit and the rear air conditioning harness for the rear air conditioning unit) each detect the temperature of the cool air immediately past the evaporator based on changes in the resistance of the built-in thermistor. The signal is used by the air conditioning amplifier.
(e) Heater Core
(1) A compact, lightweight, and highly efficient SFA (Straight Flow Aluminum)-II type heater core is used for the front and rear air conditioning units.
(f) Blower with Fan Motor Sub-assembly
(1) The front blower motor has a built-in blower controller, and the motor speed is controlled by the air conditioning amplifier using duty control.
(2) The rear blower motor speed is controlled by the air conditioning amplifier via a blower motor controller using duty control.
(g) Air Conditioning Harness
(1) The BUS connectors (in the air conditioning harness) have built-in driver ICs that communicate with each servo motor, actuate the servo motor, and have a position detection function. This enables bus communication for the servo motor wire harness, lightweight construction and a reduced number of wires.
(h) Servo Motor
(1) Pulse pattern type servo motors are used. Each servo motor assembly consists of a printed circuit board and a servo motor. The printed circuit board has three contact points, and can transmit two signals (either ON or OFF) using the differing pulse phases. The BUS connector can detect the damper position and movement direction with this signal.
6. Condenser
(a) The condenser consists of two cooling portions: a condensing portion and a super-cooling portion. The condenser also has an integrated gas-liquid separator (modulator). This condenser uses the sub-cool cycle, offering excellent heat-exchange performance.
* In the sub-cool cycle, after the refrigerant passes through the condensing portion of the condenser, both the liquid refrigerant and the gaseous refrigerant that could not be liquefied are cooled further in the super-cooling portion. Thus, the refrigerant is sent to the evaporator in an almost completely liquefied state.
* The desiccant and filter at the bottom of the modulator remove moisture and debris from the refrigerant.
(b) Service Tip
(1) The point at which the air bubbles disappear in the refrigerant of the sub-cool cycle is lower than the proper amount of refrigerant with which the system must be filled. Therefore, if the system is recharged with refrigerant based on the point at which the air bubbles disappear, the amount of refrigerant would be insufficient. As a result, the cooling performance of the system would be affected. If the system is overcharged with refrigerant, this will also lead to reduced performance. For the proper method of verifying the amount of the refrigerant and for instructions on how to recharge the system with refrigerant.
7. Compressor with Motor Assembly
(a) General
* The compressor with motor assembly is an ES27 motor driven compressor. The basic construction and operation of this compressor are the same as an ordinary scroll compressor, except that it is driven by an electric motor.
* The air conditioning inverter is integrated with the compressor.
* The air conditioning inverter (compressor with motor assembly) is supplied with power from the HV battery at a nominal voltage of DC 288V.
* The electric motor is actuated by 3-phase alternating current (288 V) supplied by the air conditioning inverter. As a result, the air conditioning system is actuated without depending on the operation of the engine, thus realizing a comfortable air conditioning system and low fuel consumption.
* Due to the use of an electric motor to drive the compressor with motor assembly, the compressor speed can be controlled at the required speed calculated by the air conditioning amplifier. Thus, the cooling and dehumidification performance and power consumption are optimized.
* Low-moisture permeation hoses are used for the suction and discharge hoses at the compressor in order to minimize the entry of moisture into the refrigeration cycle.
* The compressor motor uses high-voltage alternating current. If a short or open circuit occurs in the compressor, the hybrid vehicle control ECU will shut off the air conditioning inverter circuit in order to stop the power supply to the compressor motor.
NOTICE:
In order to ensure the proper insulation of the internal high-voltage portion of the compressor and the compressor housing, compressor oil (ND11) with a high level of insulation performance is used. Therefore, never use compressor oil other than the ND11 type compressor oil or a compressor oil having equivalent lubrication and electrical insulation properties.
(b) Construction
* The compressor with motor assembly consists of a spirally wound fixed scroll and variable scroll that form a pair, a brushless motor, an oil separator, a motor shaft and air conditioning inverter.
* The fixed scroll is integrated with the housing. Because the rotation of the shaft causes the variable scroll to revolve while maintaining the same posture, the volume of the space that is partitioned by both scrolls varies to perform the suction, compression, and the discharge of the refrigerant gas.
* Locating the suction port directly above the scrolls enables direct suction, thus realizing improved suction efficiency.
* Containing a built-in oil separator, this compressor is able to separate the compressor oil that is intermixed with the refrigerant and circulates in the refrigeration cycle, reducing the amount of oil that circulates.
* The air conditioning inverter converts the HV battery nominal voltage of DC 288V into AC 288V that is used to operate the compressor.
8. Ambient Temperature Sensor
(a) The ambient temperature sensor detects the ambient temperature based on changes in the resistance of its built-in thermistor. This signal is used by the air conditioning amplifier.
9. Heater Water Pump Assembly
(a) A heater water pump is used to circulate coolant for the heater core. This provides stable heater performance even if the engine is stopped due to THS-II control.
(b) A pump with low resistance to water flow is used.
10. Compressor Control (Compressor Speed Control)
(a) The air conditioning amplifier calculates the target compressor speed. Then, the air conditioning amplifier transmits the target compressor speed to the hybrid vehicle control ECU. The hybrid vehicle control ECU controls the air conditioning inverter based on the target speed data. This control is performed in order make the compressor operate at a speed that suits the operating conditions of the air conditioning system.
(b) The air conditioning amplifier calculates the target evaporator temperature, which includes. Accordingly, the air conditioning amplifier controls the compressor speed to an extent that does not inhibit the proper cooling performance or defogging performance. As a result, comfort and low fuel consumption can be realized.