US3945216A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refrigeration systems
Assignee: Svenska Rotor Maskiner AB
•
Filing: 1974-12-16
•
Granted: 1976-03-23
•
Expires: 1994-12-16
Abstract
Abstract Vehicle air-conditioning and other refrigerator systems utilizing specified helical screw compressors and operated under specified conditions and using specified refrigerants and oils. Also disclosed are improved hydrocarbon compressor systems which also utilize specified helical screw compressors and are operated under specified conditions using specified oils selected in relation to the hydrocarbon being compressed.
Inventors
- 👤 Hjalmar Schibbye
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:45
CPC Classifications
F; F04; F04C; F04C29/00; F04C29/02; F04C18/00; F04C18/08; F04C18/12; F04C18/14; F04C18/16; F25; F25B; F25B43/00; F25B43/02
Claims Analysis
Total Claims: 49
Claim 1
Independent Claim
311 words
Refrigeration apparatus comprising in combination: an oil injected helical screw compressor for compressing gaseous halocarbon refrigerant, an oil separator connected to said compressor to receive a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant for separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant, a condenser connected to said oil separator to receive said compressed gaseous refrigerant for liquifying said refrigerant, an evaporator connected to said condenser by a conduit means containing an expansion valve for evaporating said liquified refrigerant to the gaseous state, means for returning said evaporated gaseous refrigerant to the suction end of said compressor, and means for recycling said oil containing dissolved refrigerant to said compressor, said compressor having a male rotor and a female rotor, said male rotor having a diameter of up to about 105 mm and means for being rotated to provide a male rotor tip speed of between about 5 and 30 m/sec, said compressor having a discharge pressure of between about 10 and 30 kp/cm 2 , the dielectric constants of said oil (ε r ) and said liquified refrigerant (ε r ), and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e .sup..sup.[(c . P.sbsp.1 ) /u.sup.] and when x < 1 ##EQU3## wherein Y is a value between 25 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50°C, v is the kinematic viscosity of the pure oil in centistokes at 50°C, P 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU4## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 2
Dependent Claim
311 words
Refrigeration apparatus comprising in combination: an oil injected helical screw compressor for compressing gaseous halocarbon refrigerant, an oil separator connected to said compressor to receive a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant for separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant, a condenser connected to said oil separator to receive said compressed gaseous refrigerant for liquifying said refrigerant, an evaporator connected to said condenser by a conduit means containing an expansion valve for evaporating said liquified refrigerant to the gaseous state, means for returning said evaporated gaseous refrigerant to the suction end of said compressor, and means for recycling said oil containing dissolved refrigerant to said compressor, said compressor having a male rotor and a female rotor, said male rotor having a diameter of up to about 105 mm and means for being rotated to provide a male rotor tip speed of between about 5 and 30 m/sec, said compressor having a discharge pressure of between about 10 and 30 kp/cm 2 , the dielectric constants of said oil (ε r ) and said liquified refrigerant (ε r ), and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e .sup..sup.[(c . P.sbsp.1 ) /u.sup.] and when x < 1 ##EQU3## wherein Y is a value between 25 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50°C, v is the kinematic viscosity of the pure oil in centistokes at 50°C, P 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU4## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 3
Dependent Claim
23 words
The apparatus of claim 1 wherein the rotor diameter is between 30 and 105 mm; and wherein Y is between 50 and 100.
Claim 4
Dependent Claim
25 words
The apparatus of claim 1 wherein the rotor diameter is between 40 and 105 mm; x ≧ 1; and Y is between 50 and 100.
Claim 5
Dependent Claim
74 words
The apparatus of claim 1 adapted to be used as a vehicle air-conditioner having a capacity of between 1,000 and 5,000 kcal/h; said condenser is cooled by ambient air; said male rotor has a diameter between 40 and 55 mm and is operated at at least 1,200 rpm; said refrigerant is difluorodichloromethane; and said oil has a dielectric constant between about 4.9 and 8 and a v value between about 270 and 660 cSt.
Claim 6
Dependent Claim
13 words
The apparatus of claim 4 wherein said oil is a synthetic polyglycol oil.
Claim 7
Dependent Claim
73 words
The apparatus of claim 1 adapted to be used as an air-conditioner having a capacity of between 2.5 and 50 tons of refrigeration, wherein said male rotor has a diameter of between 40 and 105 mm and is operated at between about 2900 and 3600 rpm; said refrigerant is difluoromonochloromethane; and said oil has a dielectric constant between about 1.3 and 2.2 and a v value of between about 80 and 550 cSt.
Claim 8
Dependent Claim
20 words
The apparatus of claim 6 wherein said oil is a synthetic hydrocarbon oil having a dielectric constant of about 2.1.
Claim 9
Dependent Claim
36 words
The apparatus of claim 1 wherein said means for recycling said oil containing dissolved refrigerant is a direct pipe connection between said oil separator and said compressor and x has a value between 1 and 1.5.
Claim 10
Dependent Claim
36 words
The apparatus of claim 4 wherein said means for recycling said oil containing dissolved refrigerant is a direct pipe connection between said oil separator and said compressor and x has a value between 1 and 1.5.
Claim 11
Dependent Claim
36 words
The appartus of claim 6 wherein said means for recycling said oil containing dissolved refrigerant is a direct pipe connection between said oil separator and said compressor and x has a value between 1 and 1.5.
Claim 12
Independent Claim
167 words
A method of operating a vehicle air-conditioner comprising: condensing compressed gaseous difluorodichloromethane refrigerant to a liquid in a condenser cooled by ambient air, evaporating said liquified refrigerant in an evaporator at a temperature between about -5°C and 10°C to form gaseous refrigerant, compressing said gaseous refrigerant in a helical screw compressor having a male rotor with a diameter between 40 and 55 mm operated at between 1,200 and 14,000 rpm while admixing oil containing dissolved refrigerant with said gaseous refrigerant to form a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant at a discharge pressure of at least 10 kg/cm 2 , separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant and feeding said compressed gaseous refrigerant to said condenser to be liquified, and recycling said oil containing dissolved refrigerant from said oil separator to said compressor, said oil having a dielectric constant at 50°C of between 4.9 and 8 and a kinematic viscosity at 50°C of between about 270 and 660 cSt.
Claim 13
Independent Claim
167 words
A method of operating a vehicle air-conditioner comprising: condensing compressed gaseous difluorodichloromethane refrigerant to a liquid in a condenser cooled by ambient air, evaporating said liquified refrigerant in an evaporator at a temperature between about -5°C and 10°C to form gaseous refrigerant, compressing said gaseous refrigerant in a helical screw compressor having a male rotor with a diameter between 40 and 55 mm operated at between 1,200 and 14,000 rpm while admixing oil containing dissolved refrigerant with said gaseous refrigerant to form a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant at a discharge pressure of at least 10 kg/cm 2 , separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant and feeding said compressed gaseous refrigerant to said condenser to be liquified, and recycling said oil containing dissolved refrigerant from said oil separator to said compressor, said oil having a dielectric constant at 50°C of between 4.9 and 8 and a kinematic viscosity at 50°C of between about 270 and 660 cSt.
Claim 14
Dependent Claim
24 words
The method of claim 11 wherein said oil containing dissolved refrigerant is recycled to said compressor from said oil cooler without any applied cooling.
Claim 15
Dependent Claim
28 words
The method of claim 12 wherein said oil containing dissolved refrigerant is recycled to said compressor at a temperature not more than 5°C below the compressor discharge temperature.
Claim 16
Independent Claim
267 words
A method of operating small refrigeration systems comprising: condensing compressed gaseous halocarbon refrigerant to a liquid in a condenser, evaporating said liquified refrigerant in an evaporator to form gaseous refrigerant, compressing said gaseous refrigerant in a helical screw compressor having a male rotor with a diameter between 30 and 105 mm operated at between about 2,900 and 3,600 rpm while admixing oil containing dissolved refrigerant with said gaseous refrigerant to form a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant at a discharge pressure of between about 30 and 10 kg/cm 2 , separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant and feeding said compressed gaseous refrigerant to said condenser to be liquified, recycling said oil containing dissolved refrigerant from said oil separator to said compressor, the dielectric constants of said oil and liquified refrigerant, and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e .sup..sup.[(c . P.sbsp.1 ) /u.sup.] and when x < 1 ##EQU5## wherein Y is a value between 25 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50° C, v is the kinematic viscosity of the pure oil in centistokes at 50° C, p.sub. 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU6## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 17
Independent Claim
267 words
A method of operating small refrigeration systems comprising: condensing compressed gaseous halocarbon refrigerant to a liquid in a condenser, evaporating said liquified refrigerant in an evaporator to form gaseous refrigerant, compressing said gaseous refrigerant in a helical screw compressor having a male rotor with a diameter between 30 and 105 mm operated at between about 2,900 and 3,600 rpm while admixing oil containing dissolved refrigerant with said gaseous refrigerant to form a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant at a discharge pressure of between about 30 and 10 kg/cm 2 , separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant and feeding said compressed gaseous refrigerant to said condenser to be liquified, recycling said oil containing dissolved refrigerant from said oil separator to said compressor, the dielectric constants of said oil and liquified refrigerant, and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e .sup..sup.[(c . P.sbsp.1 ) /u.sup.] and when x < 1 ##EQU5## wherein Y is a value between 25 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50° C, v is the kinematic viscosity of the pure oil in centistokes at 50° C, p.sub. 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU6## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 18
Dependent Claim
37 words
The method of claim 14 wherein said refrigerant is difluoromonochloromethane and wherein said oil has a dielectric constant at 50°C of between 1.2 and 2.2 and a viscosity of v of between about 80 and 550 cSt.
Claim 19
Dependent Claim
28 words
The method of claim 15 wherein said oil containing dissolved refrigerant is recycled to said compressor at a temperature not more than 5°C below the compressor discharge temperature.
Claim 20
Dependent Claim
31 words
The method of claim 14 wherein said oil containing dissolved refrigerant is recycled to said compressor without applied cooling at a temperature not more than 10°C below the compressor discharge temperature.
Claim 21
Dependent Claim
304 words
Refrigeration apparatus comprising in combination: an oil injected helical screw compressor for compressing gaseous halocarbon refrigerant, an oil separator connected to said compressor to receive a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant for separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant, a condenser connected to said oil separator to receive said compressed gaseous refrigerant for liquifying said refrigerant, an evaporator connected to said condenser by a conduit means containing an expansion valve for evaporating said liquified refrigerant to the gaseous state, means for returning said evaporated gaseous refrigerant to the suction end of said compressor, and means for recycling said oil containing dissolved refrigerant to said compressor, said compressor having a male rotor and a female rotor, said male rotor having a diameter of between about 105 and 300 mm and means for being rotated to provide a male rotor tip speed of between about 15 and 50 m/sec, said compressor having a discharge pressure of between about 10 and 30 kp/cm 2 , the dielectric constants of said oil and liquified refrigerant, and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r ∝ - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e.sup.[.sup.(c . P.sbsp.1) /u.sup.] and when x < 1 ##EQU7## wherein Y is a value between 30 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50°C, v is the kinematic viscosity of the pure oil in centistokes at 50°C, P 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU8## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 22
Dependent Claim
304 words
Refrigeration apparatus comprising in combination: an oil injected helical screw compressor for compressing gaseous halocarbon refrigerant, an oil separator connected to said compressor to receive a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant for separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant, a condenser connected to said oil separator to receive said compressed gaseous refrigerant for liquifying said refrigerant, an evaporator connected to said condenser by a conduit means containing an expansion valve for evaporating said liquified refrigerant to the gaseous state, means for returning said evaporated gaseous refrigerant to the suction end of said compressor, and means for recycling said oil containing dissolved refrigerant to said compressor, said compressor having a male rotor and a female rotor, said male rotor having a diameter of between about 105 and 300 mm and means for being rotated to provide a male rotor tip speed of between about 15 and 50 m/sec, said compressor having a discharge pressure of between about 10 and 30 kp/cm 2 , the dielectric constants of said oil and liquified refrigerant, and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r ∝ - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e.sup.[.sup.(c . P.sbsp.1) /u.sup.] and when x < 1 ##EQU7## wherein Y is a value between 30 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50°C, v is the kinematic viscosity of the pure oil in centistokes at 50°C, P 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU8## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 23
Dependent Claim
23 words
The apparatus of claim 18 wherein Y has a value between 40 and 100, and u has a value between 25 and 40.
Claim 24
Dependent Claim
33 words
The apparatus of claim 19 wherein said refrigerant is difluorodichloromethane, and wherein said oil has a dielectric constant between about 4.9 and 8 and a v value between about 40 and 330 cSt.
Claim 25
Dependent Claim
33 words
The apparatus of claim 19 wherein said refrigerant is difluoromonochloromethane, and wherein said oil has a dielectric constant between about 1.3 and 2.2 and a v value between about 80 and 550 cSt.
Claim 26
Dependent Claim
36 words
The apparatus of claim 21 wherein said means for recycling said oil containing dissolved refrigerant is a direct pipe connection between said oil separator and said compressor and x has a value between 1 and 1.5.
Claim 27
Dependent Claim
36 words
The apparatus of claim 20 wherein said means for recycling said oil containing dissolved refrigerant is a direct pipe connection between said oil separator and said compressor and x has a value between 1 and 1.5.
Claim 28
Dependent Claim
36 words
The apparatus of claim 19 wherein said means for recycling said oil containing dissolved refrigerant is a direct pipe connection between said oil separator and said compressor and x has a value between 1 and 1.5.
Claim 29
Independent Claim
268 words
A method of operating refrigeration systems comprising: condensing compressed gaseous halocarbon refrigerant to a liquid in a condenser cooled by ambient air, evaporating said liquified refrigerant in an evaporator to form gaseous refrigerant, compressing said gaseous refrigerant in a helical screw compressor having a male rotor with a diameter between 105 and 300 mm operated at between about 2,900 and 3,600 rpm while admixing oil containing dissolved refrigerant with said gaseous refrigerant to form a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant at a discharge pressure of between about 10 and 30 kg/cm 2 , separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant and feeding said compressed gaseous refrigerant to said condenser to be liquified, recycling said oil containing dissolved refrigerant from said oil separator to said compressor, the dielectric constants of said oil and liquified refrigerant, and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e .sup..sup.[(c . P.sbsp.1 ) /u.sup.] and when x < 1 ##EQU9## wherein Y is a value between 25 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50°C, v is the kinematic viscosity of the pure oil in centistokes at 50°C, P 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU10## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 30
Independent Claim
268 words
A method of operating refrigeration systems comprising: condensing compressed gaseous halocarbon refrigerant to a liquid in a condenser cooled by ambient air, evaporating said liquified refrigerant in an evaporator to form gaseous refrigerant, compressing said gaseous refrigerant in a helical screw compressor having a male rotor with a diameter between 105 and 300 mm operated at between about 2,900 and 3,600 rpm while admixing oil containing dissolved refrigerant with said gaseous refrigerant to form a mixture of compressed gaseous refrigerant and oil containing dissolved refrigerant at a discharge pressure of between about 10 and 30 kg/cm 2 , separating said compressed gaseous refrigerant from said oil containing dissolved refrigerant and feeding said compressed gaseous refrigerant to said condenser to be liquified, recycling said oil containing dissolved refrigerant from said oil separator to said compressor, the dielectric constants of said oil and liquified refrigerant, and the viscosity of the oil, satisfying the following relationships | 1n ε.sub.r - 1n ε.sub.r | = x and when x ≧ 1 v = Y .sup.. e .sup..sup.[(c . P.sbsp.1 ) /u.sup.] and when x < 1 ##EQU9## wherein Y is a value between 25 and 200, 1n is the natural logarithm, ε r is the dielectric constant at 50°C, v is the kinematic viscosity of the pure oil in centistokes at 50°C, P 1 is the discharge pressure of the compressor, u is the tip speed of the male rotor, e is the base of the natural system of logarithms, and c is a constant equal to ##EQU10## when P 1 is measured in kp/cm 2 and u is measured in m/sec.
Claim 31
Dependent Claim
32 words
The method of claim 25 wherein said refrigerant is difluorodichloromethane and the oil has a dielectric constant of between 4.9 and 8 and a v value between about 270 and 660 cSt.
Claim 32
Dependent Claim
12 words
The method of claim 26 wherein said oil is a polyglycol oil.
Claim 33
Dependent Claim
36 words
The method of claim 25 wherein said refrigerant is difluoromonochloromethane and wherein said oil has a dielectric constant at 50°C of between 1.2 and 2.2 and a viscosity v of between about 80 and 550 cSt.
Claim 34
Dependent Claim
14 words
The method of claim 28 wherein said oil has an ε r of 2.1.
Claim 35
Dependent Claim
55 words
The method of claim 29 wherein the compressor discharge temperature is between about 70°C and 110°C and wherein said oil containing dissolved refrigerant being recycled from said oil separator has not been cooled and is at a temperature of not less than 5°C below said compressor discharge temperature when it is recycled to said compressor.
Claim 36
Dependent Claim
55 words
The method of claim 25 wherein the compressor discharge temperature is between about 70°C and 110°C and wherein said oil containing dissolved refrigerant being recycled from said oil separator has not been cooled and is at a temperature of not less than 5°C below said compressor discharge temperature when it is recycled to said compressor.
Claim 37
Dependent Claim
60 words
The method of claim 25 wherein x has a value between 1 and 1.5 and wherein the compressor discharge temperature is between about 70°C and 110°C and wherein said oil containing dissolved refrigerant being recycled from said oil separator or has not been cooled and is at a temperataure of not less than about 10°C below said compressor discharge temperature.
Claim 38
Dependent Claim
23 words
The method of claim 25 wherein said recycled oil is at a temperature not less than about 5°C below said compressor discharge temperature.
Claim 39
Dependent Claim
60 words
The method of claim 25 wherein x has a value between 1 and 1.5 and wherein the compressor discharge temperature is between about 70°C and 130°C and wherein said oil containing dissolved refrigerant being recycled from said oil separator or has not been cooled and is at a temperature of not less than about 10°C below said compressor discharge temperature.
Claim 40
Dependent Claim
20 words
The method of claim 25 wherein x has a value between 1 and 1.5 and wherein the compressor discharge temperature
Claim 41
Dependent Claim
59 words
The method of claim 12 wherein x has a value between 1 and 1.5 and wherein the compressor discharge temperature is between about 70°C and 130°C and wherein said oil containing dissolved refrigerant being recycled from said oil separator has not been cooled and is at a temperature of not more than about 10°C below said compressor discharge temperature.
Claim 42
Dependent Claim
23 words
The method of claim 36 wherein said recycled oil is at a temperature not more than about 5°C below said compressor discharge temperature.
Claim 43
Dependent Claim
16 words
The method of claim 36 wherein said compressor discharge temperature is between about 80°C and 130°C.
Claim 44
Dependent Claim
59 words
The method of claim 17 wherein x has a value between 1 and 1.5 and wherein the compressor discharge temperature is between about 70°C and 130°C and wherein said oil containing dissolved refrigerant being recycled from said oil separator has not been cooled and is at a temperature of not more than about 10°C below said compressor discharge temperature.
Claim 45
Dependent Claim
15 words
The apparatus of claim 8 wherein said oil separator is an internally located oil separator.
Claim 46
Dependent Claim
15 words
The apparatus of claim 13 wherein said oil separator is an internally located oil separator.
Claim 47
Dependent Claim
15 words
The apparatus of claim 14 wherein said oil separator is an internally located oil separator.
Claim 48
Dependent Claim
15 words
The apparatus of claim 18 wherein said oil separator is an internally located oil separator.
Claim 49
Dependent Claim
15 words
The apparatus of claim 25 wherein said oil separator is an internally located oil separator.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1979-03-23 | 1979-09-22 | 1980-03-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-23 | 1983-09-22 | 1984-03-23 | $3760.00 | Window Closed / Lapsed |
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