Pump

Claim 2

A pump, comprising a cylinder having a central bore, a piston positioned in the central bore of said cylinder, means for reciprocating said piston in said bore, said central bore and said piston defining a pumping chamber, communication means to the pumping chamber of said bore, a suction connection to said communication means, a discharge connection to said communication means, and a cartridge containing a suction check valve, and a discharge check valve and being removably positioned in said communication means so that said valves may be replaced by removal and replacement of said cartridge leaving the remainder of said pump in position, each of said check valves incLuding a valve seat and a valve member with said valve members being in axial alignment with each other, the opening movement of said suction check valve member being in the opposite direction from the opening movement of said discharge check valve member.

Claim 3

A pump according to claim 1, wherein said valve members move toward each other to close.

Claim 4

A pump, comprising a cylinder having a central axial bore extending partly therethrough, said cylinder defining a transverse bore therethrough spaced from the inner end of said axial bore, said cylinder defining a port extending from the inner end of said central axial bore to said transverse bore, said cylinder defining a suction port and a discharge port in communication with said transverse bore, and a cartridge adapted to be removably positioned within said transverse bore, said cartridge containing a suction check valve, a discharge check valve and communication means to establish said suction check valve in the communication between said suction port and said port from said central axial bore of said cylinder and said discharge valve in the communication between said discharge port and said port from said central axial bore of said cylinder whereby said check valves are replaceable independent of the other pump structure, said cartridge having a cylindrical body defining a pair of recesses, said check valves being positioned in said recesses, said cartridge body defining three annular grooves, each one of said grooves functioning as a portion of the communication to one of the central axial bore port, the suction port and the discharge port in said transverse bore, and means sealing between said cartridge body and said transverse bore to isolate each of said grooves.

Claim 5

A pump, comprising a cylinder having a central axial bore extending partly therethrough, said cylinder defining a transverse bore therethrough spaced from the inner end of said axial bore, said cylinder defining a port extending from the inner end of said central axial bore to said transverse bore, said cylinder defining a suction port and a discharge port in communication with said transverse bore, and a cartridge adapted to be removably positioned within said transverse bore, said cartridge containing a suction check valve, a discharge check valve and communication means to establish said suction check valve in the communication between said suction port and said port from said central axial bore of said cylinder and said discharge valve in the communication between said discharge port and said port from said central axial bore of said cylinder whereby said check valves are replaceable independent of the other pump structure, said cartridge having a cylindrical body defining a pair of recesses, said check valves being positioned in said recesses, said cartridge body defining three annular grooves, each one of said grooves functioning as a portion of the communication to one of the central axial bore port, the suction port and the discharge port in said transverse bore, and means sealing between said cartridge body and said transverse bore to isolate each of said grooves.

Claim 6

A pump according to claim 3 wherein said cartridge body includes an outwardly extending flange for positioning said cartridge in the desired axial position within said transverse bore.

Claim 7

A pump, comprising a cylinder having a central bore extending partially therethrough, a piston in said central bore, said cylinder defining a cartridge cavity, a suction line in communication with said cartridge cavity, a discharge line in communication with said cartridge cavity, means communicating from the inner end of the central bore to said cartridge cavity, a valve cartridge removably positioned in said cartridge cavity and having a suction check valve, a discharge check valve and means establishing communication from said suction line to said suction check valve and to said communicating means to the inner end of the central bore and from said central bore communicating means to said discharge check valve and to said discharge line, said cartridge being positioned in and removable from said cartridge cavity independent of the other pump structure, and means for sealing between said valve cartridge and said cartridge cavity on each side of each of said communication means, said valve cartridge and said sealing means being preselected in size to maintain a pressure balance on said valve cartridge at all times.

Claim 8

A pump, comprising a cylinder having a central bore extending partially therethrough, a piston in said central bore, said cylinder defining a cartridge cavity, a suction line in communication with said cartridge cavity, a discharge line in communication with said cartridge cavity, means communicating from the inner end of the central bore to said cartridge cavity, a valve cartridge removably positioned in said cartridge cavity and having a suction check valve, a discharge check valve and means establishing communication from said suction line to said suction check valve and to said communicating means to the inner end of the central bore and from said central bore communicating means to said discharge check valve and to said discharge line, said cartridge being positioned in and removable from said cartridge cavity independent of the other pump structure, and means for sealing between said valve cartridge and said cartridge cavity on each side of each of said communication means, said valve cartridge and said sealing means being preselected in size to maintain a pressure balance on said valve cartridge at all times.

Claim 9

A pump according to claim 5, wherein said sealing means all have the same effective sealing diameter to assure said pressure balancing of said valve cartridge.

Claim 10

As a subcombination for use with a pump, a check valve cartridge comprising a body having a pair of recesses, a suction check valve positioned in one of said recesses, a discharge check valve positioned in the other of said recesses, means biasing said check valves to seated position, and communication means through said body for providing communication therethrough from a suction passage, through said suction check valve to a common passage and from said common passage through said discharge check valve to a discharge passage, said body being generally cylindrical in shape and at least a portion of said communication means is provided by exterNal grooves extending around said body, said check valves being in axial alignment and each of said check valves having a closing movement in the opposite direction from the closing movement of the other of said check valves.

Claim 11

As a subcombination for use with a pump, a check valve cartridge comprising a body having a pair of recesses, a suction check valve positioned in one of said recesses, a discharge check valve positioned in the other of said recesses, means biasing said check valves to seated position, and communication means through said body for providing communication therethrough from a suction passage, through said suction check valve to a common passage and from said common passage through said discharge check valve to a discharge passage, said body being generally cylindrical in shape and at least a portion of said communication means is provided by exterNal grooves extending around said body, said check valves being in axial alignment and each of said check valves having a closing movement in the opposite direction from the closing movement of the other of said check valves.

Claim 12

A subcombination according to claim 7, including a plurality of sealing grooves and sealing rings in the exterior of said body to seal on both sides of each of said communication grooves.

Claim 13

A subcombination according to claim 7, wherein said body is generally bolt-shaped and includes a head having an outwardly extending flange to limit the insertion travel of the body into a bore and external threading spaced from said head and adapted to receive a nut to retain said cartridge in operating position.