Compressor
DCFirst Claim
1. A compressor for compressing a refrigerant having liquid and gaseous phases, comprising:
- at least one centrifugal compressor stage having an impeller mounted on a shaft, the shaft being supported by oilless radial bearings;
an electric motor for driving the shaft, the motor including a rotor connected to the shaft;
axial locating means associated with the shaft to restrict axial movement thereof;
a housing enclosing the motor and said at least one impeller, said housing incorporating an axially extending gas inlet and a gas outlet passage;
gas throttling means in the inlet to control the supply of gas to the impeller, passageways in the housing to convey liquid refrigerant to cool the motor and to convey refrigerant gas from the motor to the gas inlet; and
control means to control the gas throttling means in response to a refrigeration load, said control means adapted to generate control signals based on said load, said throttling means responsive to said control signals.
6 Assignments
Litigations
0 Petitions
Reexamination
Accused Products
Abstract
A centrifugal type refrigerant compressor comprises at least one impeller (17, 18), electric motor (27) and drive shaft (22) mounted on non-lubricated radial bearings, such as magnetic or foil gas bearings (23, 24), with axial locating means (26) associated with the shaft (22) to restrict axial movement thereof with respect to the compressor housing (12). The housing (12) encases the motor (27) and the compressor and defines the gas inlet (31) and the gas outlet (16) passageways. Gas throttling means (34) is provided in the inlet (31), and a control means (30) varies the speed of the motor (27) and the throttling means (34) to control the compression ratio and mass flow through the compressor in accordance with the refrigeration load.
199 Citations
31 Claims
-
1. A compressor for compressing a refrigerant having liquid and gaseous phases, comprising:
-
at least one centrifugal compressor stage having an impeller mounted on a shaft, the shaft being supported by oilless radial bearings; an electric motor for driving the shaft, the motor including a rotor connected to the shaft; axial locating means associated with the shaft to restrict axial movement thereof; a housing enclosing the motor and said at least one impeller, said housing incorporating an axially extending gas inlet and a gas outlet passage; gas throttling means in the inlet to control the supply of gas to the impeller, passageways in the housing to convey liquid refrigerant to cool the motor and to convey refrigerant gas from the motor to the gas inlet; and control means to control the gas throttling means in response to a refrigeration load, said control means adapted to generate control signals based on said load, said throttling means responsive to said control signals. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. A refrigeration compressor comprising:
-
at least one centrifugal compressor stage having an impeller mounted on a shaft; an electric motor to drive the shaft, the motor including a rotor connected to the shaft and the shaft being supported by active magnetic bearings having control circuitry to maintain a predetermined spacing between rotating and stationary bearing surfaces; axial locating means associated with the shaft to restrict axial movement thereof; a housing enclosing the motor and impeller, said housing incorporating an axially extending gas inlet and a gas outlet passage; passageways in the housing to convey refrigerant to cool the motor and to convey refrigerant gas from the motor to the gas inlet; gas throttling means in the inlet to control the supply of gas to the impeller, said gas throttling means comprising a plurality of radially extending vanes in the gas inlet, each vane being rotatable between open and closed positions about a radial axis by a control ring within the housing in response to control signals from said control means; and control means to control the gas throttling means in response to a refrigeration load. - View Dependent Claims (21, 22, 23, 24)
-
-
25. A refrigeration system comprising:
-
a compressor having at least one centrifugal compressor stage with an impeller mounted on a shaft; an electric motor to drive the shaft, the motor including a rotor connected to the shaft and the shaft being supported by oilless radial bearings; axial locating means associated with the shaft to restrict axial movement thereof; a housing enclosing the motor and impeller, said housing incorporating an axially extending gas inlet and a gas outlet passage;
gas throttling means in the inlet to control the supply of gas to the impeller;control means to control the gas throttling means in response to load; a refrigerant condenser to condense the refrigerant gas passing from the gas outlet passage; an expansion chamber; an expansion device; and an evaporator means, wherein said control means receives input signals from the evaporator means, pressure transducers in the gas inlet and gas outlet passage, gas throttling means, motor power supply means and motor speed sensor means and operates to adjust the motor speed and gas throttling means in accordance with system load and logic control parameters to maintain predetermined refrigerant flow through the compressor. - View Dependent Claims (26, 27, 28, 29, 30, 31)
-
Specification