Abstract: A scroll compressor having a scroll wall arrangement with a fixed scroll having fixed scroll walls and an orbiting scroll having orbiting scroll wall, an inlet at a radially outer portion and an outlet at a radially central portion, a first flow path defined by the orbiting and fixed scroll walls and extending from the inlet to the outlet, gas entering through inlet at a pressure and exhausting through outlet at a second pressure higher than the first pressure. Scroll wall arrangement having a second inlet through which gas enters at a third pressure and follows a second fluid path where it is exhausted through the outlet at the second pressure to form two flow paths having respective inlets. The third pressure at which gas enters through inlet is different from the first pressure, and lower than the second pressure.

Abstract: Apparatus is described for treating an effluent fluid stream from a semiconductor manufacturing process tool. The apparatus comprises a combustion chamber, means for heating the combustion chamber, and a nozzle for injecting the effluent stream into the combustion chamber. The apparatus is configured to enable a fuel and an oxidant to be selectively injected into the effluent stream as required to optimise the combustion conditions for a particular effluent stream. In one to embodiment, a lance projecting into the nozzle selectively injects an oxidant into the effluent stream, and a sleeve surrounding the nozzle selectively injects a fuel into the effluent stream.

Abstract: A vacuum system for extracting a stream of a multi-phase fluid from a photolithography tool comprises a pumping arrangement for drawing the fluid from the tool, and an extraction tank located upstream from the pumping arrangement for separating the fluid drawn from the tool into gas and liquid phases. The pumping arrangement comprises a first pump for extracting gas from the tank, and a second pump for extracting liquid from the tank. In order to minimize any pressure fluctuations transmitted from the vacuum system back to the fluid within the tool, a pressure control system maintains a substantially constant pressure in the tank by regulating the amounts of liquid and gas within the tank.

Abstract: Apparatus comprising: a chamber having a chamber inlet and a chamber outlet; a first inlet for receiving a first gas stream; a second inlet for receiving a second gas stream; a first outlet for outputting the first gas stream to a first vacuum pump; a second outlet for outputting the second gas stream to a second vacuum pump; a conduit network for connecting the first inlet to the first outlet and for connecting the second inlet to the second outlet such that, for each gas stream, first and second flow paths are defined between its respective inlet and outlet, the first flow path passing through the chamber inlet and the chamber outlet, and the second flow path by-passing the chamber, and means for routing the gas streams through the network such that when one gas stream flows along its first flow path, the other gas stream flows along its second flow path.

Abstract: A method of assembling a scroll pump comprises the following steps carried out sequentially; the step of mounting a first bearing means (20) and drive shaft (14) for rotation relative to a housing (12): the step of fastening a first flange portion (48) of a bellows arrangement (34) relative to the housing (12); the step of fastening an orbiting scroll (26) to a second flange portion (56) of the bellows arrangement (34); and the step of fixing a second scroll (28) relative to the housing (12) for co-operation with the orbiting scroll (26). The second flange portion (56) is fastened to the orbiting scroll (26) with fasteners (60) which extend through a through-bore (61) in the orbiting scroll and engage with the second flange portion.

Abstract: A multi-stage vacuum pump comprises a first piston in a first cylinder defining a first stage pumping chamber and a second piston in a second cylinder defining a second stage pumping chamber. The pump has a spool valve between the first and second cylinders for controlling flow from the first stage pumping chamber to the second stage pumping chamber. Either the first cylinder and the first piston or the second cylinder and the second piston being stepped so as to define a third stage pumping chamber. The spool valve is arranged to control the flow from the second stage pumping chamber to the third stage pumping chamber.

Abstract: A self-contained replacement flush valve assembly has an annular valve seat member which is sealed to the original valve seat by an elastomeric sealing ring, the valve seat member being clamped in position by a toggle assembly mounted on a screw carried by a frame received in the cistern outlet tube. The frame is of H-shape and its upper limbs are pivotally connected to the valve seat member, the lower limbs having a sliding engagement with pivoted arms of the toggle assembly to resist rotation of the toggle assembly. The toggle arms are pivotally retracted during insertion of the toggle assembly and frame into the outlet tube, but fall into extended positions so that on tightening the screw the arms clamp against the lower end of the outlet tube.

Abstract: A fire extinguisher of the type comprising a burstable container adapted to provide a high mass flow rate of discharged extinguishant is provided with venting means so adapted to direct the flow of extinguishant from the container that the reaction forces upon the container during discharge of extinguishant compensate one another to minimize the resultant force upon the container. The venting means comprise at least one diaphragm burstable by a detonator device housed in a frangible well which extends into the container.