1. A gas generator comprising a tubular housing of a pressure-resistant material and defining a chamber, a propellant strand in said housing chamber, said propellant strand having an envelope surrounding said propellant strand, wherein said envelope is dimensionally stable and rests substantially against the entire outer surface of said propellant strand and has at least a portion spaced from an inner surface of said chamber, and said envelope being formed such that in the case of an increase in pressure said envelope expands and rests against the inner surface of said chamber.
2. The gas generator as claimed in claim 1, wherein said tubular housing comprises a plurality of layers.
3. The gas generator as claimed in claim 1, wherein said propellant strand is cylindrical.
4. The gas generator as claimed in claim 1, wherein on at least part of the outer surface of said propellant strand, said propellant strand is provided with a coating of an ignition mixture.
5. The gas generator as claimed in claim 1, wherein said envelope is formed of a metal film.
6. The gas generator as claimed in claim 1, wherein said envelope is formed of a plastic film.
7. The gas generator as claimed in claim 6, wherein said plastic film is metal-coated.
8. The gas generator as claimed in claim 1, wherein the periphery of the envelope extends a first distance from the longitudinal axis of said envelope under ambient conditions, the periphery of said envelope extending a second distance from the longitudinal axis of said envelope upon said envelope expanding, said second distance being greater than said first distance.
9. The gas generator as claimed in claim 1, wherein said gas generator is designed to be used in a vehicle occupant restraint system.
10. A gas generator comprising a tubular housing of a pressure-resistant material and defining a chamber, a propellant strand in said housing chamber, said propellant strand having an envelope surrounding said propellant strand, wherein said envelope is dimensionally stable and rests substantially against the entire outer surface of said propellant strand, and said envelope being formed such that in the case of an increase in pressure said envelope expands and rests against an inner surface of said chamber, wherein said housing has an inner layer as well as an outer layer of plastic material as well as a middle layer of aluminum connected with said inner and outer layers.
11. A gas generator comprising a tubular housing of a pressure-resistant material and defining a chamber, a propellant strand in said housing chamber, said propellant strand having an envelope surrounding said propellant strand, wherein said envelope is dimensionally stable and rests substantially against the entire outer surface of said propellant strand, said envelope being formed such that in the case of an increase in pressure said envelope expands and rests against an inner surface of said chamber, wherein on at least part of the outer surface of said propellant strand, said propellant strand is provided with a coating of an ignition mixture, and wherein said ignition mixture is a mixture of boron and potassium nitrate or aluminum and potassium perchlorate.
12. The gas generator as claimed in claim 11, wherein said envelope has a flattened portion, which is at least one time laid around the total circumference of said propellant strand.
13. The gas generator as claimed in claim 12, wherein said flattened portion has a single layer to form a double layer envelope around said propellant strand.
14. The gas generator as claimed in claim 12, wherein said flattened portion has two layers to form a triple layer envelope around said propellant strand.
15. A gas generator comprising a tubular housing of a pressure-resistant material and defining a chamber, a propellant strand in said housing chamber, said propellant strand having an envelope surrounding said propellant strand, wherein said envelope is dimensionally stable and rests substantially against the entire outer surface of said propellant strand, and said envelope being formed such that in the case of an increase in pressure said envelope expands and rests against an inner surface of said chamber, wherein on a longitudinal side of said envelope, said envelope has at least one laterally protruding flattened portion.
16. The gas generator as claimed in claim 15, wherein there are provided two substantially opposite and laterally protruding flattened portions.
17. The gas generator as claimed in claim 16, wherein said flattened portion is supported on an inner surface of said housing.
18. The gas generator as claimed in claim 15, wherein said flattened portions extend substantially over the entire length of said envelope.
19. A gas generator comprising a tubular housing of a pressure-resistant material and defining a chamber, a propellant strand in said housing chamber, said propellant strand having an envelope surrounding said propellant strand, wherein said envelope is dimensionally stable and rests substantially against the entire outer surface of said propellant strand, and said envelope being formed such that in the case of an increase in pressure said envelope expands and rests against an inner surface of said chamber, wherein said envelope surrounding said propellant strand is welded and at least partly evacuated.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An electrically driven compressor comprising:
a compression mechanism arranged and constructed to draw in a refrigerant, compress and highly pressurize the refrigerant, and then discharge the pressurized refrigerant, the compression mechanism comprising a drive shaft, wherein a refrigerant flow channel is defined between a suction side of the compression mechanism and a discharge side of the compression mechanism,
an electric motor rotatably driving the drive shaft,
a bearing rotatably supporting the drive shaft,
a motor housing defining a substantially sealed motor chamber, wherein the electric motor is disposed within the motor chamber,
a communication path linking the refrigerant flow channel to the motor chamber,
a lubricating oil supply route defined between a discharge-side region of the refrigerant flow channel and an area proximal to the bearing, the lubricating oil supply route being arranged and constructed so that a difference between the pressure at the discharge-side region of the refrigerant flow channel and the pressure at the area proximal to the bearing urges lubricating oil towards the bearing via the lubricating oil supply route, and
a lubricating oil transfer route defined between the area proximal to the bearing and a suction-side region of the refrigerant flow channel, the lubricating oil transfer route being arranged and constructed so that a difference between the pressure at the area proximal to the bearing and the pressure at the suction-side region of the refrigerant flow channel urges lubricating oil from the area proximal to the bearing toward the suction-side region of the refrigerant flow channel.
2. An electrically driven compressor as in claim 1, further comprising an oil storage area defined proximal to the bearing and communicating with the lubricating oil transfer route, the oil storage area being arranged and constructed to store lubricating oil that lubricated the bearing.
3. A method for circulating lubricating oil L through the electric compressor having a compression mechanism arranged and constructed to draw in a refrigerant, compress and highly pressurize the refrigerant, and then discharge the pressurized refrigerant, the compression mechanism comprising a drive shaft and a bearing rotatably supporting the drive shaft, wherein a refrigerant flow channel is defined between a suction side of the compression mechanism and a discharge side of the compression mechanism, comprising:
pressure-feeding lubricating oil to the bearing based upon a difference between the pressure at the discharge-side region of the refrigerant flow channel and the pressure at the area proximal to the bearing,
pressure-feeding lubricating oil from the area proximal to the bearing to the suction-side region of the refrigerant flow channel based upon a difference between the pressure at the area proximal to the bearing and the pressure at the suction-side region of the refrigerant flow channel, and
returning the lubricating oil from the suction-side region of the refrigerant flow channel to the discharge-side region of the refrigerant flow channel by operating the compression mechanism.
4. A method as in claim 3, further comprising storing the lubricating oil that lubricated the bearing in an oil storage area defined proximal to the bearing.
5. An electrically driven compressor comprising:
a compression mechanism arranged and constructed to draw in a refrigerant, compress and highly pressurize the refrigerant, and then discharge the pressurized refrigerant, the compression mechanism comprising a drive shaft,
an electric motor rotatably driving the drive shaft,
a bearing rotatably supporting the drive shaft, and
a lubricating oil route arranged and constructed to transfer lubrication oil from a discharge-side region of the compression mechanism to a suction-side region of the compression mechanism via the bearing so as to lubricate the bearing as the refrigerant is compressed by the compression mechanism.
6. An electrically driven compressor as in claim 5, wherein the lubricating oil route has a first end and a second end that respectively communicate with the discharge-side region and the suction-side region of the compression mechanism, wherein the lubricating oil route is arranged and constructed so that the lubrication oil flows from the discharge-side region to the suction-side region via the bearing due to a difference in pressure between the discharge-side region and an area proximal to the bearing and difference in pressure between the area proximal to the bearing and the suction-side region.
7. An electrically driven compressor as in claim 6, further comprising:
a lubricating oil transfer route defined between the bearing and a suction-side region of the compression mechanism, wherein a difference between the pressure at the area proximal to the bearing and the pressure at the suction-side region of the compression mechanism pressure-feeds the lubricating oil that lubricated the bearing to the suction-side region of the compression mechanism.
8. An electrically driven compressor as in claim 6, further including an oil separator communicating with the discharge-side region of the compression mechanism, the oil separator being arranged and constructed to separate the lubricating oil from compressed refrigerant that has been discharged from the compression mechanism.
9. An electrically driven compressor as in claim 6, further including an oil storage area defined proximal to the bearing, the oil storage area being arranged and constructed to store lubricating oil that lubricated the bearing before the stored lubricating oil is transferred to the suction-side region of the compression mechanism.
10. A method for circulating lubricating oil within an electrically driven compressor, the compressor having a compression mechanism that is driven by a drive shaft, an electric motor rotatably driving the drive shaft, and a bearing rotatably supporting the drive shaft, the method comprising:
generating a pressure differential between a discharge port of the compressor and a suction port of the compressor, thereby causing lubricating oil to move via a lubricating oil route from the discharge side region to the suction side region,
pressure-feeding the lubricating oil from the suction port to an area proximal to the bearing via a communication path, whereby the bearing is lubricated, and
forcing the lubricating oil that has lubricated the bearing together with a refrigerant through the compressor mechanism to the discharge port.
11. A method as in claim 10, wherein the pressure differential along the lubricating oil route is generated due to refrigerant that is compressed by the compression mechanism.
12. A method as in claim 11, wherein a first end of the lubricating oil route communicates with the discharge port and the second end of the lubricating oil route communicates with the suction port, the method further comprising forcing the lubrication oil from the discharge side region to the suction side region via the area proximal to bearing due to a difference in pressure between the discharge port and the area proximal to the bearing.
13. An method as in claim 12, further comprising pressure-feeding the lubricating oil via a lubricating oil transfer route defined between the area proximal to the bearing and a suction-side region of the compression mechanism due to a difference between the pressure at the area proximal to the bearing and the pressure at the suction-side region of the compression mechanism.
14. A method as in claim 12, further including separating the lubricating oil from compressed refrigerant that has been discharged from the compression mechanism.
15. A method as in claim 12, further including storing the lubricating oil that lubricated the bearing before the stored lubricating oil is transferred to the suction-side region.
16. A method for circulating lubricating oil within an electrically driven compressor, comprising:
separating lubricating oil from compressed refrigerant in an area proximal to and communicating with a discharge port of the compressor,
transferring the separated lubricating oil to a bearing that rotatably supports a drive shaft using a pressure-differential between the area proximal to and communicating with the discharge port and an area proximal to the bearing, wherein the bearing is lubricated with the lubricating oil,
transferring the lubricating oil that has lubricated the bearing to an area proximal to and communicating with a suction port of the compressor using a pressure-differential between the area proximal to the bearing and the area proximal to and communicating with the suction port,
drawing the lubricating oil into a compression chamber of the compressor together with refrigerant supplied via the suction port and compressing the refrigerant and lubricating oil, and
discharging the compressed refrigerant to the area proximal to and communicating with the discharge port.
17. A method as in claim 16, further comprising temporarily storing the lubricating oil separated from the compressed refrigerant before transferring the separated lubricating oil to the bearing.
18. A method as in claim 17, further comprising temporarily storing the lubricating oil that lubricated the bearing before transferring the lubricating oil to the area proximal to and communicating with the suction port.
19. An electrically driven compressor, comprising:
means for separating lubricating oil from compressed refrigerant in an area proximal to and communicating with a discharge port of the compressor,
means for transferring the separated lubricating oil to a bearing that rotatably supports a drive shaft using a pressure-differential between the area proximal to and communicating with the discharge port and an area proximal to the bearing, wherein the bearing is lubricated with the lubricating oil,
means for transferring the lubricating oil that has lubricated the bearing to an area proximal to and communicating with a suction port of the compressor using a pressure-differential between the area proximal to the bearing and the area proximal to and communicating with the suction port,
means for drawing the lubricating oil into a compression chamber of the compressor together with refrigerant supplied via the suction port and compressing the refrigerant and lubricating oil, and
means for discharging the compressed refrigerant to the area proximal to and communicating with the discharge port.
20. An electrically driven compressor as in claim 19, further comprising means for temporarily storing the lubricating oil separated from the compressed refrigerant before transferring the separated lubricating oil to the bearing.
21. An electrically driven compressor as in claim 20, further comprising means for temporarily storing the lubricating oil that lubricated the bearing before transferring the lubricating oil to the area proximal to and communicating with the suction port.