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The scroll is a simple compression concept centered around
the unique spiral shape of the scroll and its inherent properties.
Figure 5 shows the basic scroll form. Two identical scrolls are
mated together forming concentric spiral shapes (figure 6). One
scroll remains stationary, while the other is allowed to "orbit" (fig-
ure 7). Note that the orbiting scroll does not rotate or turn but
merely orbits the stationary scroll.
NOTE − During operation, the head of a scroll compressor may
be hot since it is in constant contact with discharge gas.
FIGURE 5
SCROLL FORM
FIGURE 6
STATIONARY SCROLL
ORBITING SCROLL
DISCHARGE
SUCTION
CROSS−SECTION OF SCROLLS
TIPS SEALED BY
DISCHARGE PRESSURE
DISCHARGE
PRESSURE
1
2
3
4
SUCTION
SUCTION
ORBITING SCROLL
STATIONARY SCROLL
SUCTION
SUCTION
DISCHARGE
SUCTION
INTERMEDIATE PRESSURE
GAS
CRESCENT
SHAPED
GAS POCKET
HIGH PRESSURE GAS
FLANKS SEALED
BY CENTRIFUGAL
FORCE
MOVEMENT OF ORBIT
FIGURE 7
