Abstract:
A twin-shaft pump comprising: a pumping chamber; two rotatable shafts each mounted on bearings is disclosed. Each of the two rotatable shafts comprises at least one rotor element, the rotor elements being within the pumping chamber and the two rotatable shafts extending beyond the pumping chamber to a support member. The support member comprises mounting means for mounting the bearings at a predetermined distance from each other, the predetermined distance defining a distance between the two shafts. A thermal break between the pumping chamber and the support member is provided for impeding thermal conductivity between the pumping chamber and the support member, such that the pumping chamber and support member can be maintained at different temperatures. The support member and the rotor elements are formed of different materials, a coefficient of thermal expansion of a material forming the support member being higher than a coefficient of thermal expansion of a material forming the rotor elements.
Abstract:
A pump cooling system may include a cooling body configured to be fitted to a pump housing to receive heat from the pump housing via a heat conducting path between the cooling body and pump housing. The cooling body may have a passage through which, in use, a cooling fluid is passed to conduct heat away from the cooling body. The pump cooling system includes a cooling control mechanism configured to provide a gap in the heat conducting path at pump operating temperatures below a predefined temperature so heat conduction from the pump housing to the cooling body is interrupted.
Abstract:
A pump cooling system may include a cooling body configured to be fitted to a pump housing to receive heat from the pump housing via a heat conducting path between the cooling body and pump housing. The cooling body may have a passage through which, in use, a cooling fluid is passed to conduct heat away from the cooling body. The pump cooling system includes a cooling control mechanism configured to provide a gap in the heat conducting path at pump operating temperatures below a predefined temperature so heat conduction from the pump housing to the cooling body is interrupted.
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:
A multiple stage rotary vacuum pump comprising: a stator comprising multiple pumping stages; at least one inter-stage divider separating two adjacent pumping stages; the at least one inter-stage divider comprising two walls defining a cavity therebetween, an upstream wall bounding an upstream pumping stage and a downstream wall bounding a downstream pumping stage of the two adjacent pumping stages. The cavity comprising at least a portion of a pressure relief fluid flow path, the pressure relief fluid flow path providing a path from an outlet portion of the upstream stage towards an inlet portion of the upstream stage or towards an exhaust, the pressure relief fluid flow path comprising an orifice, the orifice comprising a valve seat; and a pressure relief valve configured to move between a compressed and an elongated state, the pressure relief valve sealing the orifice when in the elongated state and being configured to move to the compressed state such that the orifice is not obstructed, in response to pressure in the upstream stage rising above a predetermined value.
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:
A multiple stage rotary vacuum pump comprising: a stator comprising multiple pumping stages; at least one inter-stage divider separating two adjacent pumping stages; the at least one inter-stage divider comprising two walls defining a cavity therebetween, an upstream wall bounding an upstream pumping stage and a downstream wall bounding a downstream pumping stage of the two adjacent pumping stages. The cavity comprising at least a portion of a pressure relief fluid flow path, the pressure relief fluid flow path providing a path from an outlet portion of the upstream stage towards an inlet portion of the upstream stage or towards an exhaust, the pressure relief fluid flow path comprising an orifice, the orifice comprising a valve seat; and a pressure relief valve configured to move between a compressed and an elongated state, the pressure relief valve sealing the orifice when in the elongated state and being configured to move to the compressed state such that the orifice is not obstructed, in response to pressure in the upstream stage rising above a predetermined value.
Abstract:
An inter-stage coupling for a multi-stage vacuum booster pump may include a first coupling face configured to be received by a first adjacent stage of the multi-stage vacuum pump; a second coupling face configured to be received by a second adjacent stage of the multi-stage vacuum pump; and a recirculator comprising a recirculation inlet aperture formed in the first coupling face, a recirculation outlet aperture formed in the first coupling face, and a recirculation conduit having a recirculation valve configured to selectively fluidly couple the recirculation inlet aperture with the recirculation outlet aperture. In this way, the pressure in a stage can be relieved by fluidly coupling the outlet aperture with the inlet aperture in order to recirculate built-up gas from one part of the first stage pump to another part of the first stage pump in order to reduce the strain on the rotor.
Abstract:
A vacuum system non-return valve has a baffle for extending across a flow path The baffle has an aperture, a perimeter of the aperture having a valve seat. The valve also has a valve member having a protrusion extending from a surface configured to mate with the valve seat, the protrusion extending through the aperture; wherein the protrusion includes a retaining portion extending outwardly from the protrusion and configured such that the retaining portion cannot pass through the aperture. The valve member and aperture are configured such that the valve member obscures the aperture and seals with the valve seat to impede a flow of fluid from an outlet end to an inlet end in a closed position and is displaceable in use to move away from the valve seat and allow a fluid flow from the inlet end to the outlet end in an open position.
Abstract:
A method for adjusting operating parameters of a vacuum pump arrangement includes determining characteristics of a gas flowing through the vacuum pump arrangement; and setting operating parameters of the vacuum pump arrangement based on the determined characteristics of the first gas. A controller can be configured to perform the method for adjusting the operating parameters of the vacuum pump arrangement in accordance with the characteristics of the gas.