Abstract: The present invention relates to a multi-stage vacuum pump comprising: first and second half-shell stator components and first and second end stator components which when assembled define a plurality of pumping chambers. The half-shell components are assembled together along respective pairs of mutual engaging longitudinal faces and the end stator components are assembled at the ends of the half-shell components at respective pairs of mutual engaging end faces. An annular channel is counter-sunk in at least one end face of each pair of mutual engaging end faces for receiving respective sealing members for sealing between the half-shell components and the end stator components.

Abstract: The present invention relates to a pump (10) comprising a shaft (15) supported for rotation by a bearing (38) carried by a bearing carrier (48), said bearing carrier having a generally outer radial portion (52) which is fixed relative to a pump housing (12) and a generally inner radial portion (54) which is fixed relative to the bearing, wherein the carrier is stiff in a radial direction between said inner and outer portions and flexible in an axial direction for restraining radial movement of the bearing and allowing axial movement.

Abstract: A multi-stage vacuum pump may include first and second half-shell components defining a plurality of pumping chambers and for assembly together along respective longitudinal extending faces; first and second end stator components for assembly at respective longitudinal seals for sealing between the first and second half-shell stator components when assembled together at the longitudinally extending faces; and annular seals for sealing between the first and second end stator components and the first and second half-shell stator components when assembled; wherein the longitudinal seals have end portions which abut against the annular seals for sealing therebetween and the first and second half-shell stator components have formations for resisting movement of the end portions away from the annular seals when the end portions are compressed between the first and second half-shell stator components.

Abstract: The present invention relates to a scroll pump (10) comprising two scrolls (20, 22) which are co-operable for pumping fluid from an inlet (24) to an outlet (26) on relative orbiting motion of the scrolls. Each scroll comprises a scroll base (30, 36) from which a spiral scroll wall (28, 34) extends generally axially towards the base of the opposing scroll. The pump comprises a tip seal arrangement comprising an axial end portion of one or both of the scroll walls which locates a tip seal (508) for resisting the passage of pumped fluid across the or both scroll walls between the or both scroll walls and the scroll base of the opposing scroll. The tip seal arrangement limits axial movement of the tip seal towards the scroll base of the opposing scroll along a first spiral region (507) of the or both scrolls between the inlet and the outlet.

Abstract: A scroll compressor may include a scroll pumping mechanism which includes an orbiting scroll having an orbiting scroll wall extending axially from an orbiting scroll plate towards a fixed scroll and a fixed scroll having a fixed scroll wall extending axially from a fixed scroll plate towards the orbiting scroll. An axial end portion of one of the scroll walls includes a first sealing arrangement and a second sealing arrangement arranged in series along the scroll wall from the inlet to the outlet for sealing between the axial end portion of the scroll wall and the scroll plate of the opposing scroll. The first sealing arrangement may have first sealing characteristics which are selected according to the sealing requirements local to the first sealing arrangement and the second sealing arrangement may have second, different sealing characteristics which are selected according to sealing requirements local to the second sealing arrangement.

Abstract: The present invention is a scroll pump comprising two intermeshing scrolls arranged so that on relative orbital movement of the scrolls gas is pumped from an inlet to an outlet. The scrolls have a plurality of successive scroll wraps I, II, II, IV, V, VI between the inlet and the outlet. There is a single-start condition in which fluid is pumped from the inlet to the outlet along a single flow path extending through each of the scroll wraps in succession and a multi-start condition in which fluid is pumped from the inlet along a plurality of flow paths which extend in parallel through radially adjacent scroll wraps and converge to a single flow path prior to the outlet. A valve arrangement is operable for switching the scroll pump between the single-start and the multi-start conditions.

Abstract: The present invention relates to a scroll pump with two scrolls that are co-operable for pumping fluid from an inlet to an outlet on relative orbiting motion of the scrolls. Each scroll comprises a scroll base from which a scroll wall extends generally axially towards the base of the opposing scroll. A gas conduit having an inlet at a first location of the pumping channel and an outlet at a second location of the pumping channel allows over-compression at the first location of the pumping channel to be exhausted to the second location of the pumping channel. A one-way valve located in the gas conduit allows the passage of gas through the conduit from the conduit inlet to the conduit outlet when a predetermined pressure differential between the first and second locations of the pumping channel is generated during roughing when the scroll inlet is at or close to atmosphere.

Abstract: A multi-stage vacuum pump comprising: first and second half-shell stator components defining a plurality of pumping chambers and for assembly together along respective longitudinally extending faces; first and second end stator components for assembly at respective longitudinal end faces of the first and second half-shell stator components; gaskets for sealing between the first and second half-shell stator components when assembled together at the longitudinally extending faces; and O-rings for sealing between the first and second end stator components and the first and second half-shell stator components when assembled; wherein annular channels intersect longitudinal recesses and each longitudinal recess comprises a stop fixed relative to the intersection, and the gasket and the longitudinal recess are configured that when the gasket is located in the recess during assembly the gasket is biased against the stop for locating an end portion of the gasket relative to the intersection.

Abstract: In situations where a vacuum system is suddenly overloaded, there is a risk of mechanical damage being sustained, for example, bearing damage, gear slippage or rotor and/or stator collisions. Sudden overloads can also lead to electrical damage, for example, over-currents or power surges. Therefore a pressure regulating apparatus is provided for use in a vacuum pumping system having an inlet, an outlet and a conduit interposed between, and in fluid communication with, the inlet and the outlet, wherein the cross-sectional area of the conduit is greater than that required to meet the conductance requirements of the inlet and the outlet.

Abstract: The present invention is a scroll pump comprising two intermeshing scrolls arranged so that on relative orbital movement of the scrolls gas is pumped from an inlet to an outlet. The scrolls have a plurality of successive scroll wraps I, II, II, IV, V, VI between the inlet and the outlet. There is a single-start condition in which fluid is pumped from the inlet to the outlet along a single flow path extending through each of the scroll wraps in succession and a multi-start condition in which fluid is pumped from the inlet along a plurality of flow paths which extend in parallel through radially adjacent scroll wraps and converge to a single flow path prior to the outlet. A valve arrangement is operable for switching the scroll pump between the single-start and the multi-start conditions.

Abstract: The present invention relates to a scroll compressor comprising a scroll pumping arrangement comprising two scrolls each having a scroll wall with inner and outer scroll wall surfaces which co-operate with respective outer and inner scroll wall surfaces of the other scroll wall providing two pairs of co-operating surfaces which, on relative orbiting motion of the scrolls, pump fluid from an inlet to an outlet of the arrangement, the scroll walls having a respective plurality of wraps I, II, III, IV, V between the inlet and the outlet and wherein the co-operating scroll wall surfaces of one of said pairs of at least one wrap are generally circular.

Abstract: A scroll compressor includes two scrolls 40, 46 having respective scroll plates 42, 48 and respective scroll walls 44, 50. The scroll walls intermesh so that on relative orbital movement of the scrolls, a volume 52, 54 of gas is trapped between the scrolls and pumped from an inlet 31 to an outlet 33. The axial extent ‘A’ of the trapped volume between the scroll plates is less along a first portion 62 of a flow path 56 between the inlet and the outlet than the axial extent ‘B’ of the trapped volume along a second portion 64 of the flow path, and the first portion is closer to the inlet than the second portion along the flow path.

Abstract: A multi-stage vacuum pump may include a sealing arrangement for sealing between the stator components of the pump. The end seals of the arrangement comprise an annular portion for sealing between end stator components and shell components and axial portions which extend from the annular portion and together with separate axial seals seal between the shell components.

Abstract: In some examples, a scroll pump 10 may include two scrolls, which are co-operable for pumping fluid from an inlet to an outlet on relative orbiting motion of the scrolls. Each scroll may include a respective scroll base from which a respective scroll wall extends generally axially towards the base of the opposing scroll. At least a first portion of one or each of the respective scroll walls has formed in an axial end face thereof a plurality of pockets distributed along the first portion for disrupting leakage of fluid from a high pressure side of the scroll wall to a low pressure side of the scroll wall.

Abstract: The present invention relates to a scroll pump with two scrolls that are co-operable for pumping fluid from an inlet to an outlet on relative orbiting motion of the scrolls. Each scroll comprises a scroll base from which a scroll wall extends generally axially towards the base of the opposing scroll. A gas conduit having an inlet at a first location of the pumping channel and an outlet at a second location of the pumping channel allows over-compression at the first location of the pumping channel to be exhausted to the second location of the pumping channel. A one-way valve located in the gas conduit allows the passage of gas through the conduit from the conduit inlet to the conduit outlet when a predetermined pressure differential between the first and second locations of the pumping channel is generated during roughing when the scroll inlet is at or close to atmosphere.

Abstract: A multi-stage vacuum pump may include first and second half-shell components defining a plurality of pumping chambers and for assembly together along respective longitudinal extending faces; first and second end stator components for assembly at respective longitudinal seals for sealing between the first and second half-shell stator components when assembled together at the longitudinally extending faces; and annular seals for sealing between the first and second end stator components and the first and second half-shell stator components when assembled; wherein the longitudinal seals have end portions which abut against the annular seals for sealing therebetween and the first and second half-shell stator components have formations for resisting movement of the end portions away from the annular seals when the end portions are compressed between the first and second half-shell stator components.

Abstract: The present invention relates to a pump (10) comprising a shaft (15) supported for rotation by a bearing (38) carried by a bearing carrier (48), said bearing carrier having a generally outer radial portion (52) which is fixed relative to a pump housing (12) and a generally inner radial portion (54) which is fixed relative to the bearing, wherein the carrier is stiff in a radial direction between said inner and outer portions and flexible in an axial direction for restraining radial movement of the bearing and allowing axial movement.

Abstract: The present application relates to a scroll compressor comprising a scroll pumping mechanism which comprises an orbiting scroll (20) having an orbiting scroll wall (34) extending axially from an orbiting scroll plate (36) towards a fixed scroll (22) and a fixed scroll having an fixed scroll wall (28) extending axially from a fixed scroll plate (30) towards the orbiting scroll. The compressor further comprises an axially extending drive shaft (14) having an eccentric shaft portion (16) so that rotation of the eccentric shaft portion imparts an orbiting motion to the orbiting scroll relative to the fixed scroll for pumping fluid from an inlet (24) to an outlet (26) of the pumping mechanism.

Abstract: The present invention relates to a scroll pump (10) comprising two scrolls (20, 22) which are co-operable for pumping fluid from an inlet (24) to an outlet (26) on relative orbiting motion of the scrolls. Each scroll comprises a scroll base (30, 36) from which a spiral scroll wall (28, 34) extends generally axially towards the base of the opposing scroll. The pump comprises a tip seal arrangement comprising an axial end portion of one or both of the scroll walls which locates a tip seal (508) for resisting the passage of pumped fluid across the or both scroll walls between the or both scroll walls and the scroll base of the opposing scroll. The tip seal arrangement limits axial movement of the tip seal towards the scroll base of the opposing scroll along a first spiral region (507) of the or both scrolls between the inlet and the outlet.

Abstract: The present application relates to a scroll pump (10) which comprises two scrolls (20, 22) which are co-operable for pumping fluid from an inlet to an outlet on relative orbiting motion of the scrolls. Each scroll (20, 22) comprises a scroll base (30, 36) from which a scroll wall (28, 34) extends generally axially towards the base of the opposing scroll. At least a first portion of one or each of the scroll walls has formed in an axial end face (3 thereof a plurality of pockets (38) distributed along said first portion for disrupting leakage of fluid from a high pressure side of said scroll wall to low pressure side of said scroll wall.