Abstract: A connector has a coupling nut rotatable on a body and lockable by means of a locking ring mounted on the nut. When slid axially to its locking position, the locking ring engages splines on both the nut and the body to prevent relative rotation. A circular spring carried in a groove on the nut engages behind a vertical wall on the inner surface of the locking ring to prevent the locking ring being unlocked. The locking ring is unlocked by pushing a release ring axially into the locking ring so that a ramp surface on the release ring pushes the spring in and allows the locking ring to be slid back.

Abstract: An electron emitter (2) has a semiconductor substrate (20) doped with an n-type region (21). A diamond layer (24) is doped by ion implantation with a p-type dopant to form a graded dopant profile region (27) that increases away from the upper surface of the diamond layer (24) and a thin insulating region (28) separating the p-type region (27) from the n-type region (21). The emitter (2) has a first electrical contact (23) on a lower surface of the substrate (20) and a second electrical contact (25) on the upper surface of the diamond layer (24) such that a voltage can be applied across the emitter (2) to cause tunneling of electrons from the n-type region (21) through the insulating region (28) into the p-type region (27), causing emission of electrons from an exposed surface (29).

Abstract: A surgical operating table has leg sections, which are displaceable about a vertical axis and a horizontal axis. Each leg section is locked in position by two gas struts, which lock respectively about the vertical and horizontal axes. Vent buttons on the gas struts are connected via push rods to opposite ends of a lateral beam. The lateral beam is engaged, close to the end coupled to the strut locking about the vertical axis, by a manual release handle beneath the foot end of the leg section. Lifting the handle displaces the one end of the beam initially and then the other end, so that the leg section is released for movement about the vertical axis before it is released for movement about the horizontal axis.

Abstract: A spinal-epidural needle assembly has a rearwardly-extending sleeve on the epidural needle that is rotatable to a limited extent on its hub and that has a series of circumferentially-extending ribs on its outer surface. The spinal needle has a collar extending forwardly from its hub and slidable along outside of the sleeve of the epidural needle. The collar has a small elastomeric pad on its inner surface, which is slidable along a smooth region to one side of the ribbed region. The spinal needle is locked longitudinally relative to the epidural needle by twisting its collar so that the elastomeric pad slides laterally over the ribbed region with the ribs gripping into the pad.

Abstract: A catheter assembly has a needle extending within a catheter and projecting from its patient end. A slider attached with the needle is slidable rearwardly along a protective housing so that the needle can be pulled out of the catheter into the housing. A resilient catch at the patient end of the housing has two plates with apertures through which the needle projects when extended, thereby holding two hooks on the catch in engagement with the catheter hub. The catheter cannot be pulled off the needle until the needle is pulled rearwardly of the catch and allows the hooks to release engagement with the hub.

Abstract: A tracheostomy assembly comprises a tracheostomy tube having an obturator inserted therein, the obturator including two resilient catches at its machine end extending along the outside of a coupling on the machine end of the tracheostomy tube and engaging lips on the coupling. This prevents the obturator being displaced rearwardly. The obturator can be disengaged from the tube by twisting it relative to the tube.

Abstract: A vacuum cleaner hose assembly has a corrugated, flexible hose with fittings at opposite ends for connection to the vacuum cleaner suction inlet and to a cleaning head. A tube or cable extends along the assembly for supply of cleaning fluid or electrical power to the cleaning head. The tube or cable is retained with the hose by means of a U-shape channel provided as a separate member bonded to the outside of the hose. The tube or cable extends within the channel as a loose fit so that it can move along the channel on flexing of the hose, thereby helping maintain flexibility of the assembly.

Abstract: An introducer, such as for an endotracheal tube, comprises a solid rod made of an aliphatic polyurethane containing about 20% barium sulphate. The hardness of the material is about 60 Shore D so that the introducer is resilient within a range of deformation and beyond this range it is bendable into a set shape that only resumes its original shape at a slower rate.

Abstract: The cuff on the patient end of a tracheal tube is attached at one end to the inside of the tube and at the opposite end to the outside of the tube. The cuff encloses an axial sleeve that is slidably mounted within the patient end of the tube and is urged forwardly by a resilient collar. The sleeve can be retracted by applying vacuum to the cuff and, when released, extends forwards to prevent the cuff occluding the patient end of the tube.

Abstract: Reinforced, cuffed tubes are made by winding a plastic reinforcing filament around the outside of tubing and then applying a flexible layer on top of the tubing to just cover the filament and form a smooth outer surface. The filament is then removed from regions of the tubing using a pick to form a series of reinforced regions and unreinforced regions along the tubing. A second layer is then coextruded over the reinforced and unreinforced regions, which includes a longitudinal lumen. The tubing is cut into tubes midway along the unreinforced regions so that there is an unreinforced region at both ends of the tubes. An inflatable cuff is attached to each tube opening into the lumen in the second layer.

Abstract: An electrical connector has two parts each with a rectangular shell surrounding contact elements. The outside of one shell and the inside of the other are enlarged in the corners and so that the two shells can only be mated when presented square-on, thereby reducing the risk that the contact elements on one part will be inadvertently contacted by the shell on the other part. The two parts have mating coding members and clamping members located outside the shells, one part having two tower formations in which the coding and clamping members are located. The width of the towers is greater than the width of the shell on the other part.

Abstract: The mask at the end of a laryngeal mask assembly is made from a flexible cylindrical member having radially projecting ledges at each end. The ends of the cylindrical member are folded axially within the member to form an annulus with an inner rib formed by the contacting ledges. One side of the rib is located in a channel around an elliptical mount member at the patient end of a tube. The other side of the rib is located in a channel around a plate, which is attached to the mount member trapping the rib between the plate and the mount member so that a cuff is formed extending around the mount member.

Abstract: A cold cathode electrode for a discharge lamp has a metal substrate supporting a layer of diamond, so as to increase the electron yield of the electrode. The substrate may be a helical nickel wire with a layer of diamond forming it into a continuous tube.

Abstract: An inertial sensor assembly has three silicon chips that are each machined to form a respective vibrating inertial sensor, an acceleration sensor and engaging edge formations. The three chips are assembled in an orthogonal arrangement by engaging the edge formations with one another.

Abstract: A current transformer assembly has an annular transformer encompassing a busbar where it projects through the wall of equipment. The assembly has an electrically-insulative housing bolted to the equipment wall. The housing has a rear wall with an aperture through which the busbar extends, the transformer being located in a recess between the rear wall of the housing and the front of the equipment wall. The housing is open on its front and has a removable cover plate. The busbar is bolted to the upper surface of a plinth in the housing, which also supports the end of a cable entering through the front wall and bolted to the busbar.

Abstract: An electrical system has a solid state switch controlled by a circuit emulating the thermal sensor of an electrothermal circuit breaker. A current sensor senses current flowing through the switch. In one arrangement, the current sensor supplies an output to a multiplier, which derives a voltage representative of a current squared, this being supplied to a resistor capacitor circuit having a time constant emulating the thermal sensor. In another arrangement, the output of the current sensor is supplied via an A/D converter to a processor that calculates the difference between heat gain and heat loss of the emulated thermal sensor. The switch is opened when the emulated temperature exceeds a threshold.

Abstract: A method of removing undesirable fluid from the respiration passages of a patient uses a closed system suction catheter assembly having a protective sleeve enclosing an aspirating catheter extending through a sliding seal in a patient coupling. The catheter has an antimicrobial surface such as formed by silver sulfadiazine which reduces the accumulation of bacteria while the catheter is within the protective sleeve and prolongs the useful life of the assembly.

Abstract: An operating table has two leg sections each of which has a rotatable shaft extending along its length. Each shaft carries a gear that engages another gear fixed with the table such that raising or lowering the leg section causes the shaft to rotate. A helical spring extends helically around each shaft and is arranged to coil up when the leg section is lowered, so that the weight of the section is counterbalanced.

Abstract: A spinal epidural needle assembly has a spinal needle assembly insertable in an epidural needle assembly. The spinal needle assembly has a rotatable cam lever on its hub, which engages a resilient tongue formed from the hub. The spinal needle assembly is locked with the epidural assembly by pushing in the cam lever, which displaces the tongue inwardly into frictional contact with the epidural needle hub.

Abstract: A multi-color display has a matrix of cells containing an ionizable gas and fluorescent layers (18) that fluoresce with different colors. The display has rows of cathodes (21) and anodes (20) one of each of which is exposed within each cell so that individual cells can be energized. Each cathode (21) has at least one field-emitter (23) which may be either an uncoated cone, a cone coated with a material with a negative electron affinity, such as a diamond film (27), or formed with a negative electron affinity material, such as diamond. Cells may include an aluminum layer (17) and a dielectric layer (16) for reflecting UV and VUV radiation.