Dual capacity compressor with reversible motor and controls arrangement therefor

Patent · Tue Dec 02 04:00:00 EST 1980

OSTI ID:863733

Sisk, Francis J ^[1]

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1. Washington Township, Fayette County, PA

A hermetic reciprocating compressor such as may be used in heat pump applications is provided for dual capacity operation by providing the crankpin of the crankshaft with an eccentric ring rotatably mounted thereon, and with the end of the connecting rod opposite the piston encompassing the outer circumference of the eccentric ring, with means limiting the rotation of the eccentric ring upon the crankpin between one end point and an opposite angularly displaced end point to provide different values of eccentricity depending upon which end point the eccentric ring is rotated to upon the crankpin, and a reversible motor in the hermetic shell of the compressor for rotating the crankshaft, the motor operating in one direction effecting the angular displacement of the eccentric ring relative to the crankpin to the one end point, and in the opposite direction effecting the angular displacement of the eccentric ring relative to the crankpin to the opposite end point, this arrangement automatically giving different stroke lengths depending upon the direction of motor rotation. The mechanical structure of the arrangement may take various forms including at least one in which any impact of reversal is reduced by utilizing lubricant passages and chambers at the interface area of the crankpin and eccentric ring to provide a dashpot effect. In the main intended application of the arrangement according to the invention, that is, in a refrigerating or air conditioning system, it is desirable to insure a delay during reversal of the direction of compressor operation. A control arrangement is provided in which the control system controls the direction of motor operation in accordance with temperature conditions, the system including control means for effecting operation in a low capacity direction or alternatively in a high capacity direction in response to one set, and another set, respectively, of temperature conditions and with timer means delaying a restart of the compressor motor for at least a predetermined time in response to a condition of the control means operative to initiate a change in the operating direction of the compressor when it restarts.

• Assignee: Westinghouse Electric Corp. (Pittsburgh, PA)
• Patent Number(s): US 4236874
• Application Number: 06/016,638
• OSTI ID: 863733
• Country of Publication: United States
• Language: English

Related Subjects

/417/74/
accordance
according
air
air conditioning
alternatively
angular
angular displacement
angularly
application
applications
arrangement
automatically
capacity
chambers
change
circumference
compressor
condition
conditioning
conditions
connecting
connecting rod
control
control arrangement
control means
controls
crankpin
crankshaft
dashpot
delay
delaying
depending
desirable
determined time
direction
displaced
displacement
dual
dual capacity
eccentric
eccentricity
effect
effecting
encompassing
forms
giving
heat
heat pump
hermetic
hermetic shell
impact
including
initiate
insure
intended
intended application
interface
lengths
limiting
lubricant
main
means
means limit
means operative
mechanical
mechanical structure
motor
motor operation
mounted
mounted thereon
operating
operation
operative
opposite
opposite direction
outer
outer circumference
passages
piston
predetermined
predetermined time
provide
provided
providing
pump
reciprocating
reciprocating compressor
reduced
refrigerating
relative
respectively
response
restart
restarts
reversal
reversible
reversible motor
rod
rotatably
rotatably mounted
rotated
rotating
rotation
set
shell
stroke
stroke length
structure
temperature
temperature conditions
thereon
time
timer
utilizing
values
various
various forms