Abstract: A capacitive liquid level sensor (1). The sensor comprises a sensor body in the form a tongue with a freely depending portion (3) extending to a distal tip (6) at its lowermost end. A set of spaced capacitive electrodes (7) extend along the tongue towards the distal tip. In use, when the distal tip (6) of the tongue is immersed in a body of liquid, the capacitance between the electrodes (7) changes depending on the depth of the body of liquid. The width of the tongue increases in the downward direction at least for part of the bottom half of the freely depending part of the tongue.

Abstract: A liquid filter, for example for a condensate reservoir (1), formed of a printed circuit board (8) comprising a plurality of holes (9) forming a filter screen through the printed circuit board. A first set of capacitive elements (16, 17) are formed in the printed circuit board (8) forming a first capacitive sensor (12) capable of measuring the depth of the liquid adjacent to the filter. The capacitive elements (16,17) may be shielded (19) on one side such that they measure the depth on one side of the filter. A second set of capacitive elements (16?, 17?) may be provided to measure the depth of the liquid on the opposite side of the filter.

Abstract: A rotary pump comprising a housing (1) defining an annular chamber with inlet and outlet ports (12;11), a flexible annular diaphragm (3) forming one side of the chamber spaced opposite an annular wall of the housing (1), and a partition (13) extending across the chamber. The diaphragm (3) comprises an outer surface which engages the annular wall of the housing (1), and an inner surface opposite the first surface, wherein the outer surface is configured to be pressed progressively against the opposite wall of the housing (1), by a rotating means, to force fluid around the chamber. The rotary pump also comprises a reinforcement ring (4) surrounding the rotating means, and which comprises an embedded portion (30) embedded in an inner portion of a central region of the diaphragm (3), and a support portion (34) having a radially outwardly facing surface (35) which faces and supports the inner surface of the diaphragm (3) adjacent to the reinforcement ring (4) during operation of the rotary pump.

Abstract: A rotary pump comprising a housing (1) defining an annular chamber with inlet and outlet ports (12;11) spaced apart around the chamber, a flexible annular diaphragm (3) forming one side of the chamber spaced opposite an annular wall of the housing (1), the diaphragm (3) being sealed at its edges to the housing (1), a partition (13) extending across the chamber from a location between the inlet and outlet ports (12;11) to the diaphragm (3). The diaphragm (3) is configured to be pressed progressively against the opposite wall of the housing (1) to force fluid drawn in at the inlet port (12) on one side of the partition (13) around the chamber and to expel it at the outlet port (11) at the other side of the partition (13). The outer face of the annular diaphragm (3) has a trough (40) at the part of the diaphragm (3) which faces the inlet port (12) and/or at the part of the diaphragm 3 which faces the outlet port (11).

Abstract: A rotary pump comprising a housing (1) defining an annular chamber with inlet and outlet ports (12;11), a flexible annular diaphragm (3) forming one side of the chamber spaced opposite an annular wall of the housing (1), and a partition (13) extending across the chamber. The diaphragm (3) comprises an outer surface which engages the annular wall of the housing (1), and an inner surface opposite the first surface, wherein the outer surface is configured to be pressed progressively against the opposite wall of the housing (1), by a rotating means, to force fluid around the chamber. The rotary pump also comprises a reinforcement ring (4) surrounding the rotating means, and which comprises an embedded portion (30) embedded in an inner portion of a central region of the diaphragm (3), and a support portion (34) having a radially outwardly facing surface (35) which faces and supports the inner surface of the diaphragm (3) adjacent to the reinforcement ring (4) during operation of the rotary pump.

Abstract: A rotary pump in a housing which defines an annular chamber with an inlet and outlet port which are located on either side of a partition which extends across the chamber. A flexible annular diaphragm forms one side of the chamber and faces a wall on the housing which forms the second side of the chamber. The diaphragm is sealed at its innermost and outermost edges to the housing and has legs extending away azimuthally around and integral with the diaphragm. A swashplate is connected to the legs of the diaphragm such that in use, movement of the swashplate causes the diaphragm to press precessively against the wall of the housing to force fluid drawn in at the inlet on one side of the partition around the chamber and to expel the fluid at the outlet at the other side of the partition.

Abstract: A rotary pump in a housing which defines an annular chamber with an inlet and outlet port which are located on either side of a partition which extends across the chamber. A flexible annular diaphragm forms one side of the chamber and faces a wall on the housing which forms the second side of the chamber. The diaphragm is sealed at its innermost and outermost edges to the housing and has legs extending away azimuthally around and integral with the diaphragm. A swashplate is connected to the legs of the diaphragm such that in use, movement of the swashplate causes the diaphragm to press precessively against the wall of the housing to force fluid drawn in at the inlet on one side of the partition around the chamber and to expel the fluid at the outlet at the other side of the partition.