Radial compressor with muffled gas chambers and short stable piston skirts and method of assembling same

Claim 2

A radial compressor of the type including a cast cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said housing having one closed end and a removable cylinder head closing its other end; a drive shaft rotatably mounted in said housing and said cylinder head; an eccentric on said drive shaft, a slider block rotatably mounted on said eccentric; a pair of yokes disposed normal to each otHer and in engagement with normal surfaces of said slider block; pairs of piston assemblies connected to each yoke so that the pistons extend oppositely from each other from said yokes; said piston assemblies being press-fit connected to said yokes providing a stable connection therebetween; said pistons including a relatively short piston skirt; said pistons further including an annular groove in said piston skirts extending a major portion of the width along said skirt; a sealing ring disposed in said groove substantially the full width thereof to provide a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, the relatively wide bearing surface of said sealing ring being sufficiently wide to accomplish a fluid tight seal while providing substantial area of engagement preventing metal-to-metal contact between said piston skirts and said cylinder walls; said cylinder housing being formed to include relatively large intake and discharge cavities muffling sound energy in gases flowing therethrough during operation of the compressor, said discharge cavities molded integral with said cylinder housing between the cylinder bores; reinforcing web portions molded integral with said cylinder housing and at least partially defining said discharge cavities and providing a rigid cylinder housing structure and areas for fastening the cylinder head to said cylinder housing as well as areas for securing the entire assembly in an operational environment, and valve means to direct fluids to and from the cylinder bores.

Claim 3

A radial compressor of the type including a cast cylinder housing having cross bores therein along axes normal to each other; said housing having an integral closed end and an open end; a removable cylinder head assembly closing the open end of said cylinder housing when attached thereto; said cylinder housing being circular in form and terminating in a circumferential opening; a cylindrical sleeve member capable of being disposed about said cylinder housing enclosing the circumferential periphery thereof; a plurality of retaining pins positioned in said cylinder housing retaining said cylindrical sleeve; a first inwardly extending annular flange molded integral with said cylinder housing; a second inwardly extending annular flange molded integral with said cylinder head; main bearing assemblies each disposed in said annular flanges; a drive shaft having bearing portions positioned in alignment with and rotatably supported by said main bearing assemblies; an eccentric on said drive shaft centrally positioned within said cylinder housing; a plurality of elongated roller bearings in circumferential engagement with said eccentric; a slider block rotatably mounted upon said plurality of bearings; a first yoke assembly positioned for reciprocal movement along a first axis in said cylinder housing in a first of said cross bores; a second yoke assembly positioned for reciprocal movement along an axis normal to that of said first yoke in a second of said cross bores in said cylinder housing; said yokes including surfaces in engagement with said slider block for operation thereby as said eccentric rotates with said drive shaft; each of said yoke assemblies containing oppositely extending sockets therein; a piston assembly including a stem portion that is press-fitted within each of said oppositely extending sockets rigidly connecting the piston assemblies to said yokes; a relatively short piston skirt on said piston assemblies containing a relatively wide annular groove therein; a single Teflon sealing ring initially in the form of a flat washer positioned in said groove and being folded to a relatively flat position and being inherently biased outwardly against the cylinder walls of said cross bores; said sealing ring being of substantial width relative to said piston skirt so as to accomplish a fluid tight seal while providing a relatively large bearing surface between said piston skirt and said cylinder walls preventing metal-to-metaL contact between the piston and the cylinder; a fluid inlet chamber in the central portions of said cylinder housing defined by the closed ends of said housing and the inner sides of said piston assemblies, said inlet chamber providing sufficient volume to muffle sound energies in the incoming fluids; a pressurized fluid discharge chamber in said cylinder housing extending circumferentially adjacent the outer periphery of said housing and being defined in part by said cylindrical sleeve member and the outer surfaces of said piston assemblies, said fluid discharge chamber including muffler cavities molded integral with said cylinder housing between adjacent cylinder bores; said piston assemblies having apertures therethrough for conveying fluid from said inlet chamber to a compression chamber on the outer sides of said piston assemblies, valve means secured to the outer surface of said piston assembly regulating flow through said apertures; and valve means positioned between said compression chamber and said discharge chamber regulating flow of pressurized fluid from the compression chamber into the discharge chamber as the piston assemblies reciprocate within their respective cross bores.

Claim 4

A radial compressor of the type including a cast cylinder housing having cross bores therein along axes normal to each other; said housing having an integral closed end and an open end; a removable cylinder head assembly closing the open end of said cylinder housing when attached thereto; said cylinder housing being circular in form and terminating in a circumferential opening; a cylindrical sleeve member capable of being disposed about said cylinder housing enclosing the circumferential periphery thereof; a plurality of retaining pins positioned in said cylinder housing retaining said cylindrical sleeve; a first inwardly extending annular flange molded integral with said cylinder housing; a second inwardly extending annular flange molded integral with said cylinder head; main bearing assemblies each disposed in said annular flanges; a drive shaft having bearing portions positioned in alignment with and rotatably supported by said main bearing assemblies; an eccentric on said drive shaft centrally positioned within said cylinder housing; a plurality of elongated roller bearings in circumferential engagement with said eccentric; a slider block rotatably mounted upon said plurality of bearings; a first yoke assembly positioned for reciprocal movement along a first axis in said cylinder housing in a first of said cross bores; a second yoke assembly positioned for reciprocal movement along an axis normal to that of said first yoke in a second of said cross bores in said cylinder housing; said yokes including surfaces in engagement with said slider block for operation thereby as said eccentric rotates with said drive shaft; each of said yoke assemblies containing oppositely extending sockets therein; a piston assembly including a stem portion that is press-fitted within each of said oppositely extending sockets rigidly connecting the piston assemblies to said yokes; a relatively short piston skirt on said piston assemblies containing a relatively wide annular groove therein; a single Teflon sealing ring initially in the form of a flat washer positioned in said groove and being folded to a relatively flat position and being inherently biased outwardly against the cylinder walls of said cross bores; said sealing ring being of substantial width relative to said piston skirt so as to accomplish a fluid tight seal while providing a relatively large bearing surface between said piston skirt and said cylinder walls preventing metal-to-metaL contact between the piston and the cylinder; a fluid inlet chamber in the central portions of said cylinder housing defined by the closed ends of said housing and the inner sides of said piston assemblies, said inlet chamber providing sufficient volume to muffle sound energies in the incoming fluids; a pressurized fluid discharge chamber in said cylinder housing extending circumferentially adjacent the outer periphery of said housing and being defined in part by said cylindrical sleeve member and the outer surfaces of said piston assemblies, said fluid discharge chamber including muffler cavities molded integral with said cylinder housing between adjacent cylinder bores; said piston assemblies having apertures therethrough for conveying fluid from said inlet chamber to a compression chamber on the outer sides of said piston assemblies, valve means secured to the outer surface of said piston assembly regulating flow through said apertures; and valve means positioned between said compression chamber and said discharge chamber regulating flow of pressurized fluid from the compression chamber into the discharge chamber as the piston assemblies reciprocate within their respective cross bores.

Claim 5

The radial compressor of claim 2 including integral reinforcing portions molded with said cylinder housing providing areas for securing said removable cylinder head assembly thereto and further providing reinforcement areas to said cylinder housing resulting in a rigid assembly; said valve means secured to the outer surface of said piston comprising an annular flexible reed plate regulating flow through a series of circumferentially spaced apertures through said piston assembly; and said valve means regulating flow between the compression chamber and the discharge chamber comprising an annular discharge reed valve plate secured to a rigid plate that is in turn fastened to the cylinder walls of said cross bores, the rigid plate containing a plurality of circumferentially spaced apertures controlled by the discharge reed plate thereby regulating flow into the discharge chamber.

Claim 6

The radial compressor of claim 3 wherein the fastening of said rigid plate of the last named valve means comprises a counterbore in the radially outer end of each of said cross bores forming a shoulder seating said rigid plate in said outer end and including a recess, and a snap ring in said recess retaining said rigid plate on said shoulder.

Claim 7

The radial compressor of claim 1 wherein said press-fit connection comprises an aluminum stem on each of said piston assemblies and an aluminum socket on its respective yoke, the diameter of said stem before the press-fit connection being larger than the diameter of said socket by substantially 0.0020 inch to 0.0035 inch.

Claim 8

The radial compressor of claim 1 wherein said press-fit connection comprises an aluminum stem on each of said piston assemblies and an imperforate aluminum socket on its respective yoke, the diameter of said stem before the press-fit connection being larger than the diameter of said socket, and said stem having a hollow therein to provide a compression chamber to store air trapped between stem and socket after the press-fit connection.

Claim 9

A compact, lightweight radial compressor of the type including a cast aluminum cylinder housing having cross bores therein along axes normal to each other; each of said cross bores having a counterbore in the radially outer end thereof forming a shoulder between the bore and counterbore; said housing having an integral closed end and an open end; a removable aluminum cylinder head assembly closing the open end of said cylinder housing when attached thereto; said cylinder housing being circular in form and terminating in a circumferential opening; a cylindrical sleeve member capable of being disposed and retained about said cylinder housing and enclosing the circumferential periphery thereof; a first inwardly extending annular flange molded integral with said cylinder housing; a second inwaRdly extending annular flange molded integral with said cylinder head; main bearing assemblies each disposed in said annular flanges; a drive shaft having bearing portions positioned in alignment with and rotatably supported by said main bearing assemblies; an eccentric on said drive shaft centrally positioned within said cylinder housing; a plurality of elongated roller bearings in circumferential engagement with said eccentric; a slider block rotatably mounted upon said plurality of bearings; a first yoke assembly positioned for reciprocal movement along a first axis in said cylinder housing in a first of said cross bores; a second yoke assembly positioned for reciprocal movement along an axis normal to that of said first yoke in a second of said cross bores in said cylinder housing; said yokes including surfaces in engagement with said slider block for operation thereby as said eccentric rotates with said drive shaft; each of said yoke assemblies containing oppositely extending aluminum sockets therein; a piston assembly including an aluminum stem portion that is press-fitted within each of said oppositely extending aluminum sockets rigidly connecting the piston assemblies to said yokes; a relatively short piston skirt on said piston assemblies containing a relatively wide annular groove therein; a single Teflon sealing ring positioned in said groove; said sealing ring being of substantial width relative to said piston skirt so as to accomplish a fluid tight seal while providing a relatively large bearing surface between said piston skirt and said cylinder walls preventing metal-to-metal contact between the piston and the cylinder; a fluid inlet chamber in the central portions of said cylinder housing defined by the closed ends of said housing and the inner sides of said piston assemblies, said inlet chamber providing sufficient volume to muffle sound energies in the incoming fluids; a pressurized fluid discharge chamber in said cylinder housing extending circumferentially adjacent the outer periphery of said housing and being defined in part by said cylindrical sleeve member and the outer surfaces of said piston assemblies, said fluid discharge chamber including muffler cavities molded integral with said cylinder housing between adjacent cylinder bores; said piston assemblies having apertures therethrough for conveying fluid from said inlet chamber to a compression chamber on the outer sides of said piston assemblies, suction valve means secured to the outer surface of said piston assembly regulating flow through said apertures; discharge valve means positioned between said compression chamber and said discharge chamber regulating flow of pressurized fluid from the compression chamber into the discharge chamber as the piston assemblies reciprocate within their respective cross bores; said discharge valve means comprising as a riveted unitized assembly a rigid valve plate configured to fit said counterbore and containing a plurality of circumferentially spaced apertures, an annular discharge reed valve overlying said apertures and a retainer plate backing said reed valve to limit the movement of said reed valve when it is regulating said flow of pressurized fluid; and a retainer ring snap fastened into said counterbore to retain said discharge valve means on said shoulder.

Claim 10

A compact, lightweight radial compressor of the type including a cast aluminum cylinder housing having cross bores therein along axes normal to each other; each of said cross bores having a counterbore in the radially outer end thereof forming a shoulder between the bore and counterbore; said housing having an integral closed end and an open end; a removable aluminum cylinder head assembly closing the open end of said cylinder housing when attached thereto; said cylinder housing being circular in form and terminating in a circumferential opening; a cylindrical sleeve member capable of being disposed and retained about said cylinder housing and enclosing the circumferential periphery thereof; a first inwardly extending annular flange molded integral with said cylinder housing; a second inwaRdly extending annular flange molded integral with said cylinder head; main bearing assemblies each disposed in said annular flanges; a drive shaft having bearing portions positioned in alignment with and rotatably supported by said main bearing assemblies; an eccentric on said drive shaft centrally positioned within said cylinder housing; a plurality of elongated roller bearings in circumferential engagement with said eccentric; a slider block rotatably mounted upon said plurality of bearings; a first yoke assembly positioned for reciprocal movement along a first axis in said cylinder housing in a first of said cross bores; a second yoke assembly positioned for reciprocal movement along an axis normal to that of said first yoke in a second of said cross bores in said cylinder housing; said yokes including surfaces in engagement with said slider block for operation thereby as said eccentric rotates with said drive shaft; each of said yoke assemblies containing oppositely extending aluminum sockets therein; a piston assembly including an aluminum stem portion that is press-fitted within each of said oppositely extending aluminum sockets rigidly connecting the piston assemblies to said yokes; a relatively short piston skirt on said piston assemblies containing a relatively wide annular groove therein; a single Teflon sealing ring positioned in said groove; said sealing ring being of substantial width relative to said piston skirt so as to accomplish a fluid tight seal while providing a relatively large bearing surface between said piston skirt and said cylinder walls preventing metal-to-metal contact between the piston and the cylinder; a fluid inlet chamber in the central portions of said cylinder housing defined by the closed ends of said housing and the inner sides of said piston assemblies, said inlet chamber providing sufficient volume to muffle sound energies in the incoming fluids; a pressurized fluid discharge chamber in said cylinder housing extending circumferentially adjacent the outer periphery of said housing and being defined in part by said cylindrical sleeve member and the outer surfaces of said piston assemblies, said fluid discharge chamber including muffler cavities molded integral with said cylinder housing between adjacent cylinder bores; said piston assemblies having apertures therethrough for conveying fluid from said inlet chamber to a compression chamber on the outer sides of said piston assemblies, suction valve means secured to the outer surface of said piston assembly regulating flow through said apertures; discharge valve means positioned between said compression chamber and said discharge chamber regulating flow of pressurized fluid from the compression chamber into the discharge chamber as the piston assemblies reciprocate within their respective cross bores; said discharge valve means comprising as a riveted unitized assembly a rigid valve plate configured to fit said counterbore and containing a plurality of circumferentially spaced apertures, an annular discharge reed valve overlying said apertures and a retainer plate backing said reed valve to limit the movement of said reed valve when it is regulating said flow of pressurized fluid; and a retainer ring snap fastened into said counterbore to retain said discharge valve means on said shoulder.

Claim 11

A compact radial compressor of the type including a cast cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said cylinder housing including relatively large intake and discharge cavities muffling sound energy in gases flowing therethrough during operation of the compressor; said housing having a closed end, an open end opposite said closed end and a removable cylinder head closing its open end; a drive shaft assembly insertable as a unit into said cylinder housing through its open end; said drive shaft assembly including an integral crankshaft journaled in said housing and said cylinder head and having an eccentric, a slider block, needle bearings betwEen said slider block and said eccentric rotatably mounting said slider block on said eccentric, a pair of aluminum yokes disposed normal to each other with inwardly facing normal surfaces in engagement with normal surfaces of said slider block, means for retaining said needle bearings between said slider block and said eccentric and for maintaining front and back surfaces of said slider block out of engagement with said pair of yokes, and a pair of counterweights outboard of said pair of yokes and riveted together through said eccentric to lock said drive shaft assembly into a unit; pairs of piston assemblies including aluminum pistons connected to each yoke so that the pistons extend oppositely from each other from said yokes; said aluminum pistons being press-fit connected to said aluminum yokes providing a stable connection therebetween, said press-fit comprising a socket on one of said yoke or said piston and a stem on the other, an interference dimension of said stem being larger than an interference dimension of said socket; said pistons including a relatively short piston skirt; a sealing ring disposed in hugging relationship around said skirt and being of substantial width relative to the width of said piston skirt to provide a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, said sealing ring being at least partially exposed in said intake cavity upon reciprocation of its respective piston during operation of said compressor, means for retaining said sealing ring in hugging relationship on said skirt during operation of said compressor, the relatively wide bearing surface of said sealing ring being sufficiently wide to accomplish a fluid tight seal while providing substantial area of engagement preventing metal-to-metal contact between said piston skirts and said cylinder walls, the relatively wide bearing surface also facilitating the alignment of said stem with said socket for said press-fit after the drive shaft assembly is inserted as a unit into said cylinder housing; and valve means to direct fluids to and from the cylinder bores.

Claim 12

A compact radial compressor of the type including a cast cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said cylinder housing including relatively large intake and discharge cavities muffling sound energy in gases flowing therethrough during operation of the compressor; said housing having a closed end, an open end opposite said closed end and a removable cylinder head closing its open end; a drive shaft assembly insertable as a unit into said cylinder housing through its open end; said drive shaft assembly including an integral crankshaft journaled in said housing and said cylinder head and having an eccentric, a slider block, needle bearings betwEen said slider block and said eccentric rotatably mounting said slider block on said eccentric, a pair of aluminum yokes disposed normal to each other with inwardly facing normal surfaces in engagement with normal surfaces of said slider block, means for retaining said needle bearings between said slider block and said eccentric and for maintaining front and back surfaces of said slider block out of engagement with said pair of yokes, and a pair of counterweights outboard of said pair of yokes and riveted together through said eccentric to lock said drive shaft assembly into a unit; pairs of piston assemblies including aluminum pistons connected to each yoke so that the pistons extend oppositely from each other from said yokes; said aluminum pistons being press-fit connected to said aluminum yokes providing a stable connection therebetween, said press-fit comprising a socket on one of said yoke or said piston and a stem on the other, an interference dimension of said stem being larger than an interference dimension of said socket; said pistons including a relatively short piston skirt; a sealing ring disposed in hugging relationship around said skirt and being of substantial width relative to the width of said piston skirt to provide a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, said sealing ring being at least partially exposed in said intake cavity upon reciprocation of its respective piston during operation of said compressor, means for retaining said sealing ring in hugging relationship on said skirt during operation of said compressor, the relatively wide bearing surface of said sealing ring being sufficiently wide to accomplish a fluid tight seal while providing substantial area of engagement preventing metal-to-metal contact between said piston skirts and said cylinder walls, the relatively wide bearing surface also facilitating the alignment of said stem with said socket for said press-fit after the drive shaft assembly is inserted as a unit into said cylinder housing; and valve means to direct fluids to and from the cylinder bores.

Claim 13

The compact radial compressor of claim 8 wherein said means for retaining said sealing ring is an annular groove in said piston skirt of substantially the same width as said sealing ring therein.

Claim 14

The compact radial compressor of claim 9 wherein said annular groove includes vent means beneath said sealing ring for bypassing leakage gases thereat from one side of said piston skirt to the other side thereof to prevent said leakage gases from tending to blow said sealing ring out of said annular groove.

Claim 15

The compact radial compressor of claim 10 wherein said vent means are four vent holes equally spaced around the piston skirt joined beneath said sealing means by an additional annular groove in the aforementioned annular groove.

Claim 16

The compact radial compressor of claim 8 wherein said means for retaining said needle bearings is hardened steel, said slider block has sockets and said retaining means has extrusions interfitting with said sockets to key said retaining means to said slider block to prevent the edges of said retaining means from gouging said aluminum yokes.

Claim 17

A radial compressor of the type including a cast aluminum cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said housing having a closed end, an open end opposite said closed end and a removable cylinder head closing its open end; a shaft assembly insertable into said cylinder housing through its open end and including an integral drive shaft and eccentric rotatably mounted in said housing and said cylinder head, a slider block, needle bearings between said slider block and said eccentric rotatably mounting said slider block on said eccentric, a pair of aluminum yokes disposed normal to each other and in engagement with normal surfaces of said slider block, means for retaining said needle bearings between said slider block and said eccentriC and for maintaining front and back surfaces of said slider block out of engagement with said pair of yokes, and a pair of counterweights outboard of said pair of yokes and held together through said eccentric to lock said shaft assembly in assembled relationship; pairs of piston assemblies including aluminum pistons connected to each yoke so that the pistons extend oppositely from each other from said yokes; said aluminum pistons being press-fit connected to said aluminum yokes providing a stable connection therebetween, said press-fit comprising an imperforate socket on said yoke and a stem on said piston having a reduced diameter portion forming a shoulder engaging said yoke, the reduced diameter portion of said stem being larger than the diameter of said socket, said reduced diameter portion of said stem having a hollow therein to provide a compression chamber to store air trapped between said reduced diameter portion and socket as the result of press-fit; said pistons including a relatively short piston skirt, said pistons further including an annular groove in said piston skirts extending a substantial width along said skirt; a sealing ring disposed in said groove substantially the full width thereof to provide a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, the relatively wide bearing surface of said sealing ring being sufficiently wide to accomplish a fluid tight seal while providing substantial area of engagement preventing metal-to-metal contact between said piston skirts and said cylinder walls, the relatively wide bearing surface also facilitating the alignment of said stem with said socket after said shaft assembly is inserted into said cylinder housing; and valve means to direct fluids to and from the cylinder bores.

Claim 18

A radial compressor of the type including a cast aluminum cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said housing having a closed end, an open end opposite said closed end and a removable cylinder head closing its open end; a shaft assembly insertable into said cylinder housing through its open end and including an integral drive shaft and eccentric rotatably mounted in said housing and said cylinder head, a slider block, needle bearings between said slider block and said eccentric rotatably mounting said slider block on said eccentric, a pair of aluminum yokes disposed normal to each other and in engagement with normal surfaces of said slider block, means for retaining said needle bearings between said slider block and said eccentriC and for maintaining front and back surfaces of said slider block out of engagement with said pair of yokes, and a pair of counterweights outboard of said pair of yokes and held together through said eccentric to lock said shaft assembly in assembled relationship; pairs of piston assemblies including aluminum pistons connected to each yoke so that the pistons extend oppositely from each other from said yokes; said aluminum pistons being press-fit connected to said aluminum yokes providing a stable connection therebetween, said press-fit comprising an imperforate socket on said yoke and a stem on said piston having a reduced diameter portion forming a shoulder engaging said yoke, the reduced diameter portion of said stem being larger than the diameter of said socket, said reduced diameter portion of said stem having a hollow therein to provide a compression chamber to store air trapped between said reduced diameter portion and socket as the result of press-fit; said pistons including a relatively short piston skirt, said pistons further including an annular groove in said piston skirts extending a substantial width along said skirt; a sealing ring disposed in said groove substantially the full width thereof to provide a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, the relatively wide bearing surface of said sealing ring being sufficiently wide to accomplish a fluid tight seal while providing substantial area of engagement preventing metal-to-metal contact between said piston skirts and said cylinder walls, the relatively wide bearing surface also facilitating the alignment of said stem with said socket after said shaft assembly is inserted into said cylinder housing; and valve means to direct fluids to and from the cylinder bores.

Claim 19

The radial compressor of claim 13 wherein the reduced diameter portion of said stem is larger than the diameter of said socket by substantially 0.0020 inch to 0.0035 inch, and said relatively short piston skirt is substantially 0.380 inch wide and has an outside diameter substantially 1.775 inch to 1.780 inch.

Claim 20

A radial compressor of the type including a cast cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said housing having one closed end and a removable cylinder head closing its other end; a drive shaft rotatably mounted in said housing and said cylinder head; an eccentric on said drive shaft, a slider block rotatably mounted on said eccentric; a pair of yokes disposed normal to each other and in engagement with normal surfaces of said slider block; pairs of piston assemblies connected to each yoke so that the pistons extend oppositely from each other from said yokes; said piston assemblies being press-fit connected to said yokes providing a stable connection therebetween; said press-fit connection comprising an aluminum stem on each of said piston assemblies and an imperforate aluminum socket on its respective yoke, the diameter of said stem before the press-fit connection being larger than the diameter of said socket, and one of said stem or said socket having a hollow therein to provide a relief chamber for air trapped between stem and socket after the press-fit connection; said pistons including a relatively short piston skirt; said pistons further including an annular groove in said piston skirts extending a substantial width along said skirt; and a sealing ring disposed in said groove providing a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, the relatively wide bearing surface of said sealing ring preventing metal-to-metal contact between said piston skirts and said cylinder walls; said cylinder housing being formed to include relatively large intake and discharge cavities muffling sound energy in gases flowing therethrough during operation of the compressor.

Claim 21

A radial compressor of the type including a cast cylinder housing having cross bores including cylinder walls therein along axes normal to each other, said housing having one closed end and a removable cylinder head closing its other end; a drive shaft rotatably mounted in said housing and said cylinder head; an eccentric on said drive shaft, a slider block rotatably mounted on said eccentric; a pair of yokes disposed normal to each other and in engagement with normal surfaces of said slider block; pairs of piston assemblies connected to each yoke so that the pistons extend oppositely from each other from said yokes; said piston assemblies being press-fit connected to said yokes providing a stable connection therebetween; said press-fit connection comprising an aluminum stem on each of said piston assemblies and an imperforate aluminum socket on its respective yoke, the diameter of said stem before the press-fit connection being larger than the diameter of said socket, and one of said stem or said socket having a hollow therein to provide a relief chamber for air trapped between stem and socket after the press-fit connection; said pistons including a relatively short piston skirt; said pistons further including an annular groove in said piston skirts extending a substantial width along said skirt; and a sealing ring disposed in said groove providing a relatively wide bearing surface between said piston skirt and the cylinder walls of said cross bores, the relatively wide bearing surface of said sealing ring preventing metal-to-metal contact between said piston skirts and said cylinder walls; said cylinder housing being formed to include relatively large intake and discharge cavities muffling sound energy in gases flowing therethrough during operation of the compressor.

Claim 22

An improved method of assembling a radial compressor without screws Comprising the steps of inserting a unitized drive shaft assembly including yoke sockets into the central intake chamber of a radially bored and counterbored drum-shaped cylinder housing, press-fitting stems of unitized piston assemblies including intake valves through the radial bores into stable connections with the yoke sockets of said drive shaft assembly, snap-fastening unitized discharge valve assemblies into seated relationship in said counterbores radially outboard of said piston assemblies, and pressing a sleeve into surrounding relationship with said cylinder housing outboard of said discharge valve assemblies to form a discharge chamber around said cylinder housing.

Claim 23

An improved method of assembling a radial compressor without screws Comprising the steps of inserting a unitized drive shaft assembly including yoke sockets into the central intake chamber of a radially bored and counterbored drum-shaped cylinder housing, press-fitting stems of unitized piston assemblies including intake valves through the radial bores into stable connections with the yoke sockets of said drive shaft assembly, snap-fastening unitized discharge valve assemblies into seated relationship in said counterbores radially outboard of said piston assemblies, and pressing a sleeve into surrounding relationship with said cylinder housing outboard of said discharge valve assemblies to form a discharge chamber around said cylinder housing.

Claim 24

An improved method of partially assembling a radial four cylinder compressor to eliminate screws from moving aluminum parts including the steps of inserting a unitized drive shaft assembly including four aluminum yoke sockets through an open end of a radially bored one-piece casting to a journaled position in a closed end of the casting, aligning a pair of said yoke sockets with a pair of radial cylinder bores 90* apart in the casting and simultaneously press-fitting a pair of aluminum pistons into said pair of yoke sockets through said cylinder bores 90* apart in the casting.

Claim 25

An improved method of partially assembling a radial four cylinder compressor to eliminate screws from moving aluminum parts including the steps of inserting a unitized drive shaft assembly including four aluminum yoke sockets through an open end of a radially bored one-piece casting to a journaled position in a closed end of the casting, aligning a pair of said yoke sockets with a pair of radial cylinder bores 90* apart in the casting and simultaneously press-fitting a pair of aluminum pistons into said pair of yoke sockets through said cylinder bores 90* apart in the casting.