Structure And Operating Characteristics; Key Components; Scroll Compressor Operating Characteristics - Panasonic 4CW056MA01 Applications Manual

1.0 Structure and Operating Characteristics

1.1 Key Components

Panasonic C-SW series scroll compressors are horizontal type hermetic compressors and designed for
mobile air conditioning applications.
The pressure inside of shell is high pressure (discharge pressure). Suction refrigerant gas enters into
compression chamber directly and the motor is cooled by discharge gas. The motor is rigidly attached to the
shell; Crankshaft is supported by main frame and sub-frame which are welded to the shell. Pump assembly
consists of fixed scroll and orbiting scroll and Oldham ring. Orbiting scroll rotates on the surface of the main
frame.
Figure 1-1 Horizontal Scroll Compressor Components
See a cutaway view of C-SW series compressor in Figure1-1.

1.2 Scroll Compressor Operating Characteristics

Panasonic C-SW series scroll compressors are designed with fixed eccentric and floating orbit scroll sealing,
resulting in low sound level and minimal gas leakage and therefore excellent efficiency.
The Figure 1-2 below describes the scroll compression process:
First orbit; SUCTION gas enters at the perimeter of the scroll elements and is sealed as the scrolls rotate
approximately one revolution.
Second orbit; During the COMPRESSION process, the gas is further compressed towards the center of the
scroll elements to an intermediate pressure.
Third orbit; In the DISCHARGE orbit, the gas is further compressed to discharge pressure and then exits at
the center through the discharge port.
With a three step simultaneous process of suction, compression and discharge and two gas pockets in each
step that are 180 degrees apart, the compression process is balanced and very smooth, resulting in high
efficiency, low sound/vibration and excellent reliability.
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