Subaru Legacy/Outback

1999-2003 of release

Repair and operation of the car

The K/V compressor - a design and the principle of functioning

K/V compressor design

1 — the Forward head
2 — the Lateral block
3 — the Back head
4 — the Control valve
5 — the Back bearing
6 — Shibernaya a shovel
7 — the Rotor

8 — the Roller valve
9 — the Cylinder
10 — the Forward bearing
11 — a shaft Epiploon
12 — the Magnetic coupling of coupling
13 — the Trigger valve

The scheme of functioning of the compressor in an absorption phase

1 — the Rotor
2 — Coolant
3 — the Control valve
4 — the Back head

5 — the Low pressure chamber
6 — the Back lateral block
7 — Shibernaya a shovel
8 — a rotor Shaft

The scheme of functioning of the compressor in a release phase

1 — the Forward head
2 — the Coolant which is (pushed out)
3 — the Compressed coolant
4 — the Roller valve

5 — the Forward lateral block
6 — the Tube
7 — the High-pressure chamber

The scheme of functioning of the compressor in a compression phase

1 — a rotor Shaft

2 — Coolant

Design of the trigger valve of compressor assembly

1 — the To-shaped cavity
2 — the Control ball

3 — the Forward head
4 — the Spring

Functioning of the trigger valve at small loadings and at the time of start of the compressor

1 — the High-pressure chamber
2 — the Trigger valve (is open)

3 — Shibernaya a shovel
4 — the Rotor

Functioning of the trigger valve in a normal operating mode of the compressor

1 — the High-pressure chamber
2 — the Trigger valve (is closed)

3 — Shibernaya a shovel
4 — the Rotor

Principle of functioning of the control valve of the compressor

1 — Inlet port
2 — the Spherical washer
3 — the Spring

4 — the Control valve
5 — Coolant

Principle of functioning of the lubrication system of the compressor

1 — the Forward bearing
2 — Shibernaya a shovel
3 — the Back bearing
4 — the Low pressure chamber

5 — the Rotor
6 — Oil port
7 — the High-pressure chamber
8 — a shaft Epiploon

Principle of functioning of the magnetic coupling of coupling of the K/V compressor

1 — the Bearing
2 — the Winding of the magnetic coupling
3 — the Compressor

4 — a rotor Shaft
5 — the Driving pulley
6 — the Driving plate

General information

On all models the compressor of shiberny type is installed.

The rotor of the compressor equipped with five mobile shiberny shovels in the radial direction rotates in the elliptic cylinder. During rotation of a rotor there is a reduction of the working volume concluded between two next shiberny shovels leading to compression of the gaseous coolant concluded in the cylinder. In this case the compressor functions as the pump with 10-fold on one turn of a rotor three-phase (absorption, compression and pushing out) a running cycle.

From the final party of the cylinder the dosing roller valve providing a vypuskaniye of the compressed coolant at excess by pressure of compression of some certain value is installed. Tightness (by air) of landing of a shaft of a rotor in a forward head of compressor assembly is provided by means of an epiploon. The trigger valve which is built in the lateral block provides creation of counter-pressure on shiberny shovels of a rotor.

Assembly is filled with necessary amount of the compressor oil distributed between internal components and providing their greasing. Tightness on oil is provided at the expense of the digit pressure of the pushed-out coolant.

Principle of functioning

Absorption

The gaseous coolant which is under low pressure is exhausted from the evaporator at the expense of the rotor of the compressor of depression created at rotation and via the control valve is involved in a low pressure chamber in a back head of compressor assembly. Further, due to rotation of a shiberny rotor, coolant through two inlet ports in the back lateral block is soaked up in the working cylinder. Tightness of chambers of the cylinder is (by air) provided due to circulation of compressor oil.

Compression

At further rotation of a rotor the volume of a valvate chamber formed by shiberny shovels with the gaseous coolant concluded in it starts contracting, providing increase of pressure of a working body.

Pushing out

At the last (third) stage of a cycle of a surge when pressure of the compressed coolant reaches some stipulated value, the roller valve opens and coolant on the cylindrical channel provided in the forward lateral block is issued in a high-pressure chamber of a forward head where by means of a special reflector separates from oil and moves on an exit of compressor assembly.

Trigger valve

The trigger valve serves for maintenance of the demanded counter-pressure level in the volume closed between shiberny shovels for the purpose of ensuring mobility of the last at start of the compressor. The valve is equipped with a control ball and a spring, built in the forward lateral block of assembly and by the end is opened in the To-shaped cavity from the rotor party of the lateral block.

At an insignificant difference between pressure in low pressure and high-pressure parts of assembly shiberny shovels have excessively free landing in the directing rotor grooves. The similar situation is quite typical at small loadings, and also at the initial stage of rotation of the compressor and is fraught with emergence of vibrations due to violation of smoothness of the course of the dangling shovels. The control ball of the trigger valve which is propped up by a spring rises over a saddle and provides creation on shovels of the drawing-in counter-pressure that guarantees smoothness of functioning of assembly at low loading and at the time of start of the compressor.

In a normal operating mode when the difference between pressure in high-pressure and low pressure parts of assembly is essential, a control ball, overcoming resistance of a spring nestles on a saddle of the valve and blocks the connecting channel. Thus pressure of oil port via the lateral block is put to a shovel end face, providing its subpress.

Control valve

The control valve consists of a spherical washer and a spring and is installed in the inlet port of a back head. Directly after a compressor stop the difference between pressure in high-pressure and low pressure parts of assembly is very essential that in the absence of the control valve would lead to the return rotation of a rotor and pushing out of coolant in the evaporator. As soon as the compressor stops, the coolant which is under a high pressure wrings out a spherical washer of the valve up, blocking thereby inlet port and preventing creation of a stream of a working body from high-pressure part of the highway in the low pressure.

Greasing

Lubricant compressor oil accumulates in the lower part of a high-pressure chamber, from where under pressure of coolant is pushed out via oil channels in the forward lateral block up and provides greasing of a forward end face of a rotor. Besides, the part of oil on certain canals in the lower part of the working cylinder is forced out down and moves to a back end face of a rotor. Under the influence of internal pressure in the compressor the oil greasing a rotor from both parties comes to a low pressure chamber of assembly. The oil containing in the gaseous coolant leaving the evaporator is banished via the low pressure camera, providing greasing of the back bearing, and also, on the special channel in a body of a shaft moves to the inlet port of the cylinder, on the road greasing the forward bearing and an epiploon. As pressure in the inlet port of the cylinder is slightly lower, than in a low pressure chamber, the oil greasing all components of compressor assembly is soaked up to the port and with a stream of coolant is overtaken back in a high-pressure chamber.

Magnetic coupling of coupling of the compressor

The magnetic coupling is fixed on a shaft of a rotor of compressor assembly and serves for a torque transmission from the engine to the К/В compressor. When passing current through a coupling winding the driving plate is attracted, consolidating a pulley and a shaft of a rotor in the uniform module. At the switched-off compressor the pulley continues to rotate freely, without setting a rotor in motion.

On the models of 3.0 l equipped 6-tsrovysm with engines the sensor of blocking of the compressor is in addition provided. At a compressor stop as a result of refusal the sensor provides an otpuskaniye of the magnetic coupling for the purpose of maintenance of the normal functioning given by the same, as the compressor a belt of the steering pump.

System of a delay of activation of the compressor

Activation of the fan of a heater at included To/in leads to transfer on ECM of a special signal. Having received a signal, the module of management defines, whether the engine is started and at in case of an affirmative answer activates central air relay. The maximum time of a delay of activation of coupling of the compressor after operation of the relay makes 0.8 seconds. The function chart of the described process is presented on an illustration.

Control system of functioning of the compressor

As it was already described above, activation To/in with the fan of a heater leads to operation of the relay of central air. After activation of the compressor also main and auxiliary fans of the cooling system turn on.

The special thermooperating amplifier at the activation makes shutdown of the coupling of coupling of the compressor, and also both fans.

Shutdown of the compressor and fans happens also at operation of the sensor switch of pressure.

The thermooperating amplifier

The amplifier provides shutdown of the magnetic coupling of coupling of the K/V compressor for the purpose of prevention of frosting of the evaporator when lowering temperature of the last below 3 °C. When temperature approaches critical value, the thermistor established between evaporator heat exchanger plates makes disconnection of a basic chain of the amplifier that involves deactivation of the K/V relay and shutdown of the magnetic coupling of coupling of the compressor.

System of shutdown of the compressor at acceleration

Use of the button of inclusion To/in (On/off) is followed by delivery on ECM of the corresponding information signals.

At revenues to the module of management of a signal of full opening of a butterfly valve of ECM develops command for the K/V compressor stop (if the last at the time of receiving a signal was included). A problem of system is ensuring the maximum acceleration performance of the vehicle during acceleration.

The K/V relay is located in the main assembly block of safety locks in the left part of a motive compartment.

System of stabilization of turns of idling

Compensation of the increasing load of the engine at turning on of the K/V compressor is carried out due to increase of turns of the single
the course on a signal of the special electromagnetic IAC valve.

When obtaining information on inclusion of K/B ECM makes the activation of the valve of stabilization of turns of idling (IAC) leading to opening of a special bypass on which the part of an air stream moves in the engine bypassing the throttle case.