초록 ▼

A pump is formed by a housing (10) having an inlet (11) for connection to a source of fluid and an outlet (12) for pumped fluid. A rotor (15) is rotatable within the housing and the inlet (11) and the outlet (12) are spaced apart around the path of the rotor (15) in the housing. The rotor (15) has s

A pump is formed by a housing (10) having an inlet (11) for connection to a source of fluid and an outlet (12) for pumped fluid. A rotor (15) is rotatable within the housing and the inlet (11) and the outlet (12) are spaced apart around the path of the rotor (15) in the housing. The rotor (15) has surfaces (16a, 16b, 16c, 16d) that form, with the housing (10), closed chambers (18a, 18b, 18c, 18d) which travel around the housing (10) to convey fluid from the inlet (11) to the outlet (12). The housing (10) carries a seal (14) that is located between the inlet (11) and the outlet (12) in the direction of travel of the rotor (15). The seal (14) co-operates with the rotor surfaces (16a, 16b, 16c, 16d) as the surfaces (16a, 16b, 16c, 16d) pass between the outlet (12) and the inlet (11) to prevent the formation of a chamber during said passage and so prevent fluid flow from the outlet (12) to the inlet (11). Such a pump is easily and cheaply produced and is particularly useful in medical applications.

대표청구항 ▼

1. A pump comprising: a housing formed of a resilient material,a rotor path defined within the housing,ana first inlet formed in the housing at a first position on said rotor path,ana first outlet formed in the housing at a second position on said rotor path spaced from said first position,a rotor r

1. A pump comprising: a housing formed of a resilient material,a rotor path defined within the housing,ana first inlet formed in the housing at a first position on said rotor path,ana first outlet formed in the housing at a second position on said rotor path spaced from said first position,a rotor rotatable in said housing around an axis, the rotor having an outer rotor surface which seals againstcontacts said rotor path and resiliently distends said rotor pathhousing to provide a fluid-tight seal between the rotor and the rotor path, andat least one first chamber-forming concavity inwardly formed from said outer rotor surface, said first concavity a) having a first concave surface which is concave in planes including the rotor axis,b) being surrounded by said outer rotor surface, andc) solely forming a first conveying chamber travelling around said rotor path on rotation of the rotor to convey fluid around the housing; anda first resilient seal carried by the housing, located on said rotor path and extending between the first outlet and the first inlet in the direction of rotation of said rotor, said first resilient seal being adapted to seal with and be resiliently deformed by said outer rotor surface surrounding said first concavity to prevent fluid flow from said first outlet to said first inlet past the first seal, and to seal with said first concave surface of said first concavity, as said first concavity passes between the first outlet and the first inlet to squeeze fluid from the first chamber into the first outlet, andwherein the housing includes a second inlet and a second outlet spaced axially along the rotor from the first inlet and the first outlet,wherein the rotor includes at least one second chamber-forming concavity forming, with the housing, a second conveying chamber travelling around the housing between the second inlet and the second outlet to convey fluid from said second inlet to said second outlet,wherein the housing between the second outlet and the second inlet in the direction of rotation of the rotor includes a second resilient seal adapted to seal with and be resiliently deformed by the outer rotor surface of said second concavity to prevent fluid flow from said second outlet to said second inlet past said second seal, and to seal with a second concave surface of said second concavity, as said second concavity passes between the second outlet and the second inlet to squeeze fluid from the second chamber into the second outlet,wherein the rotor is movable axially between a) the above described position which aligns the first concavity with the first inlet and the first outlet and the second concavity with the second inlet and second outlet, and b) an alternative position of which aligns the second concavity with the first inlet and the first outlet while closing the second inlet and the second outlet. 2. A pump according to claim 1, wherein the first seal has a rotor-engaging surface having an axial and angular extent generally the same as the axial and angular extent of the at least one first chamber-forming concavity of the rotor. 3. A pump according to claim 1, wherein the housing includes a generally cylindrical interior surface co-operating with the rotor to form said first conveying chamber. 4. A pump according to claim 3, wherein the first seal interrupts said cylindrical interior surface, extending axially and circumferentially relative to said cylindrical interior surface. 5. A pump according to claim 4, wherein the first seal projects radially inwardly of the cylinder defined by said cylindrical interior surface. 6. A pump according to claim 1, wherein the first seal has angularly spaced first and second ends around the path of the rotor, the first outlet being formed adjacent said first end. 7. A pump according to claim 6, wherein the housing includes a generally cylindrical interior surface forming said rotor path and co-operating with the rotor to form said first conveying chamber, the first inlet and the first outlet being formed in said cylindrical interior surface of the housing. 8. A pump according to claim 6, wherein the first inlet and the first outlet are formed in said first seal. 9. A pump according to claim 1, wherein the first seal has angularly spaced first and second ends around the path of the rotor, the first inlet being formed adjacent said second end. 10. A pump according to claim 1, wherein the first seal is formed by a block of resilient material. 11. A pump according to claim 1, wherein the first seal is formed by a membrane and a member resiliently supporting the membrane, the membrane sealing against the rotor. 12. A pump according to claim 11, wherein the resilient member is formed by a container of fluid or gas under pressure. 13. A pump according to claim 11, wherein the resilient member is formed by a spring. 14. A pump according claim 1, wherein two or more first chamber-forming concavities are provided on said rotor at axially aligned angularly spaced positions around the rotor, each first chamber-forming concavity co-operating with said first seal as the first concave surface passes from said first outlet to said first inlet in the direction of rotation of the rotor. 15. A pump according claim 1, wherein the housing includes a second inlet and a second outlet spaced axially along the rotor from first-mentioned inlet and outlet,wherein the rotor includes at least one second chamber-forming concavity forming, with the housing, a second conveying chamber travelling around the housing between the second inlet and the second outlet to convey fluid from said second inlet to said second outlet,wherein the housing between the second outlet and the second inlet in the direction of rotation of the rotor includes a second resilient seal adapted to seal with and be resiliently deformed by the outer surface of said at least one second chamber-forming concavity to prevent fluid flow from said second outlet to said second inlet past said second seal, and to seal with a concave surface of said second concavity, as said second concavity passes between the second outlet and the second inlet to squeeze fluid from the second chamber into the second outlet. 16. A pump according to claim 15, wherein the rotor is: movable axially in one direction to align the first-mentioned at least one chamber-forming concavity and the second inlet and second outlet while closing the first-mentioned inlet and the first-mentioned outlet, andmoveable axially in an opposite direction to align the at least one chamber-forming concavity with the first inlet-mentioned and the first-mentioned outlet while closing the second inlet and the second outlet. 17. A pump according to claim 16, wherein the housing is formed of a resilient material, the rotor engaging and resiliently distending the housing to provide a fluid-tight seal between the housing and housing-contacting portions of the rotor. 18. A pump according to claim 171, wherein the housing has a generally cylindrical interior surface,wherein the rotor has a co-operating generally cylindrical exterior surface sealing against said interior surface, andwherein said at least one first chamber-forming concavity is formed in said generally cylindrical exterior surface. 19. A pump according to claim 18, wherein said exterior surface is formed by a land on the rotor, the land having axially spaced ends and the rotor being provided with radially relieved portions at said ends. 20. A pump according to claim 18, wherein a circumferential rib is formed on each relieved portion, each rib sealing resiliently against the interior surface of said housing. 21. A pump according to claim 1, wherein only a single first inlet and a single first outlet are provided, the rotor conveying fluid from said first inlet to said first outlet. 22. A pump according to claim 1, further including a secondanother first inlet and a secondanother first outlet spaced circumferentially around the housing from the first mentioned inlet and first outlet,the rotor further including a plurality of chamber-forming concavities conveying fluid from the first mentioned inlet to the first mentioned outlet and from the secondanother first inlet to the secondanother first outlet, andwherein the first mentioned seal is located between the secondanother first inlet and the first mentioned outlet and a secondanother first seal is provided between the first mentioned outlet and the secondanother first inlet. 23. A pump according to claim 22, wherein the rotor has at least four first chamber-forming concavities. 24. A pump according to claim 1, wherein the rotation of the rotor is reversible to pump fluid from the first outlet to the first inlet. 25. A pump according to claim 1, further including a drive for rotating the rotor. 26. A pump according to claim 1, wherein the housing and first seal are a unit including of an insert moulding, an over-moulding or a dual shot moulding. 27. A pump according to claim 1, wherein the housing, first seal and rotor are a single injection moulding. 28. A pump comprising: a housing,a rotor path defined within the housing,an inlet formed in the housing at a first position on said rotor path,an outlet formed in the housing at a second position on said rotor path spaced from said first position,a rotor rotatable in said housing, the rotor having at least two apices formed on the rotor and sealing against said rotor path,at least one first surface formed on said rotor between said at least two apices, anda chamber formed in said at least one first surface between the at least two apices and the housing, and travelling around said rotor path on rotation of the rotor to convey fluid around the housing,a resilient seal carried by the housing located on said rotor path and so extending between the outlet and the inlet in the direction of rotation of said rotor that each apex seals with, and resiliently deforms, the seal, as each apex passes between the outlet and the inlet to prevent fluid flow from said outlet to said inlet past the seal;in which the rotor is movable axially relative to the housing between a first axial position and a second axial position, andthe rotor further including at least one second chamber-forming surface spaced axially from said at least one first chamber-forming surface, the at least one first chamber-forming surface forming a chamber with the housing in said first axial position of the rotor and the at least one second chamber-forming surface forming a chamber with the housing in said second axial position of the rotor. 29. A pump according to claim 28, wherein the volume of the chamber formed by the at least one first chamber-forming surface is different from the volume of the chamber formed by the at least one second chamber-forming surface. 30. A pump according to claim 29, wherein the volume of the chamber formed by the at least one first chamber-forming surface is greater than the volume of the chamber formed by the at least one second chamber-forming surface. 31. A pump according to claim 28, wherein a device is provided for moving said rotor axially between said first and second axial positions. 32. A pump according to claim 31, in which rotation of said rotor in one direction acts to convey fluid from the inlet to the outlet with the rotor in the first axial position,in which rotation of said rotor in an opposite direction will move said rotor axially between said first and second axial positions,in which a reversal of rotation from the opposite direction to the one direction with the rotor in the second axial position will move the rotor back to the first axial position, andin which rotation in said opposite direction acts to convey fluid from the outlet to the inlet by said at least one second chamber-forming surface. 33. A pump according to claim 32, wherein said device includes a mechanism acting between the housing and the rotor for moving the rotor axially between the first and second axial positions relative to the housing depending on rotation of said rotor in the one or the opposite direction. 34. A pump according to claim 33, wherein said mechanism comprises a pin member and a helical slot member, one member being on the rotor and the other member being on the housing, rotation of the rotor between the one direction and the opposite direction moving the pin in a helical path along said slot to move the rotor axially between the first and second axial positions. 35. A pump comprising: a housing,a rotor path defined within the housing,an inlet formed in the housing at a first position on said rotor path,an outlet formed in the housing at a second position on said rotor path spaced from said first position,a rotor rotatable in said housing, the rotor having at least two apices formed on the rotor and sealing against said rotor path,at least one surface formed on said rotor between said at least two apices, anda chamber formed by said at least one surface between the at least two apices and the housing, and travelling around said rotor path on rotation of the rotor to convey fluid around the housing,a resilient seal carried by the housing located on said rotor path and so extending between the outlet and the inlet in the direction of rotation of said rotor that each apex seals with, and resiliently deforms, the seal, as each apex passes between the outlet and the inlet to prevent fluid flow from said outlet to said inlet past the seal; andin which the rotor is movable axially relative to the housing between a first axial position in which the at least one chamber-forming surface forms a chamber with the housing and a second axial position in which the rotor cooperates with the housing to provide a direct communication between the inlet and the outlet. 36. A pump according to claim 35, wherein a device is provided for moving said rotor axially between said first and second axial positions. 37. A pump according to claim 36, in which rotation of said rotor in one direction acts to convey fluid from the inlet to the outlet with the rotor in the first axial position,in which rotation of said rotor in an opposite direction will move said rotor axially between said first and second axial positions, andin which a reversal of rotation from the opposite direction to the one direction with the rotor in the second axial position will move the rotor back to the first axial position. 38. A pump according to claim 37, wherein said device includes a mechanism acting between the housing and the rotor for moving the rotor axially between the first and second axial positions relative to the housing depending on rotation of said rotor in the one or the opposite direction. 39. A pump according to claim 38, wherein said mechanism comprises a pin member and a helical slot member, one member being on the rotor and the other member being on the housing, rotation of the rotor between the one direction and the opposite direction moving the pin in a helical path along said slot to move the rotor axially between the first and second axial positions.