Abstract: A photon drag detector having a block of semi-conductor material with two opposite faces through one of which a beam of radiation can enter and from the other of which it can emerge; spaced end electrodes in contact with said block, one adjacent to each of said opposite faces; at least two intermediate electrodes in contact with said block, arranged intermediate and spaced from said end electrodes and spaced from each other; and an impedance connecting said end electrodes; whereby the change in sensitivity of the detector with the position of the beam in the said block can be made small. The block of semi-conductor material is typically bar shaped with the opposite faces substantially parallel end faces of the bar. The bar is conveniently cylindrical. The electrodes are preferably ring electrodes, embracing the block and parallel with the planes of the opposite faces.

Abstract: Systems for the recognition of speech by computer have usually required t the speech be of a strictly standarized nature, free of such features as regional accent, and unaccompanied by background noise. The problem has been to produce a system providing information which will allow accurate recognition in the presence of noise, and with non-standard speech sounds.

Abstract: The invention facilitates the calibration of VOR equipment by synthesis of series of waveforms representative of different positions in azimuth.Digital data representative of a frequency modulated component of the VOR waveform is stored in a first memory area (1) and digital data representative of an added sine wave component of the waveform is stored in a second memory area (2). By appropriate cyclic data retrieval from the memory areas and combination of the data (7) together with digital to analogue conversion (8) and filtering (10) the VOR waveform corresponding to a particular azimuth may be synthesized.

Abstract: A hardness test indenter having a retangular base and four operative plane aces, a first pair of said faces meeting each other in a straight ridge with an included angle in the range from about 60.degree. to about 150.degree.; and a second pair of said faces making substantially equal angles with said straight ridge and so disposed in relation to one another and to said ridge that the first pair of faces have edges substantially symmetrically disposed in relation to said straight ridge; and said second pair of faces having between them an included angle in the range from about 60.degree. to about 150.degree.; the said straight ridge having a length not more than about 0.5 millimeter and not less than about 0.05 millimeter.

Abstract: A liquid such as a hydrocarbon fuel is sprayed electrostatically into a gas tream. Spraying is achieved by supplying the liquid to a porous member having a plurality of termini within an electrostatic field. The electrostatic field strength is enhanced at the termini so that liquid which soaks through the porous member to the termini breaks up under the influence of the locally high electrostatic field into a stream of droplets which are repelled by their charge away from the termini. The droplets become finely dispersed in a passing gas stream.The invention finds particular application as an electrostatic carburettor for dispersing petrol into an air stream for combustion in an internal combustion engine. The invention can also be utilized for re-dispersing fuel droplets deposited on the wall of an air/fuel intake.

Abstract: The present invention provides thin film magneto-resistive readout apparatus for providing readout from magnetic memory devices such as magnetic tapes, the apparatus comprising a thin film magneto-resistive readout head element, a narrow pulse generator for applying sensing current to the readout head element in the form of trains of narrow pulses, and a signal averaging circuit connected to receive output signals from the readout head element for deriving an average output signal for the pulses in each train.

Abstract: A wafer having microelectronic circuit chips thereon having electrical connections between the chips arranged so that effectively the chips are on a surface which at least in one direction is unbounded. The electrical connections may be arranged so that the chips are effectively on the surface of a cylinder, or they may be effectively on a helix. The electrical connections may optionally be arranged so that the chips are effectively on a toroid, or on an endless helix. The output connections from a chip adjacent one edge of the wafer may be connected through electrical conductors direct to the input connections of a chip adjacent the opposite edge of the wafer.

Abstract: The invention concerns the use of pin or pile members in combination with a uction anchor to increase greatly the pull-out resistance of the anchor. The suction anchor acts as a base from which the pin or pile members are driven into the bed material. The pin members may be driven substantially vertically into the bed material externally of the anchor skirt or may be contained within the skirt and driven through apertures in the skirt to provide additional lateral anchorage.

Abstract: Position detecting apparatus having a target comprising radiation emitting eans for emitting radiation to define four points in non-planar relationship such that a first set of three of the points lies in a first target plane while a second set of three of the points lies in a second target plane which may for example be substantially normal to the first target plane; a camera having a focal plane on which images of objects presented to the camera are formed, the camera being arranged for viewing said target, and being provided at said focal plane with a two-dimensional array of photo sensitive elements which can receive radiation from the radiation emitting means of the said target; and a computer arranged to scan said two dimensional array to generate signals indicative of the position of images of the radiation emitting means on the array, whereby the position of the target, and hence of an object to which it is attached, may be determined in relation to a selected reference plane.

Abstract: A device for arresting and/or launching a discrete body at the end of a pline in which the body forms a sliding seal and through which the body is carried by fluid flow comprises a length of pipe continuous with and opening into the pipeline, and having a closed end remote from the pipeline, the internal cross-section of said length of pipe being substantially the same as that of the pipeline; a casing forming a chamber on the exterior of the said length of pipe; an external connection for fluid flow to or from the chamber; and at least one through which the chamber and the interior of the said length of pipe communicate.

Abstract: A release hook assembly comprising a pivoted hook retainable by a pivoted capement member for closure of the assembly, a displaceable release device to engage the escapement member when retaining the hook, and a locking member to engage the release device for maintaining the assembly in the closed position, whereby in operation displacement of the locking member from the closed position allows subsequent displacement of the release device and consequent pivotal motion of the hook free from the escapement member.

Abstract: Apparatus for use in the control of arc welding, especially the automatic ntrol of consumable electrode arc welding employs a technique of reflecting an ultrasonic pulse from that end of a strip of weld filler material which is melting into the weldpool. The time taken from transmission to return of the ultrasonic pulse is measured to provide a measure of the length of filler material projecting beyond the welding torch, which can then be used eg to facilitate automatic control of the welding process. Apparatus using magnetrostrictive and or magnetoelastic methods of ultrasonic pulse transmission and reception are described. Also apparatus using a piezo-electric method for pulse transmission and reception is described which is especially useful for a non-ferromagnetic weld filler strip.

Abstract: A crane with a crane rope; means for attaching a load to the crane rope; a crane winch having a drum on which the crane rope can be wound; a crane motor which can drive the crane winch for hauling in or letting out the crane rope; a measuring winch having a drum with a measuring line windable thereon of length sufficient to reach at least as far as the crane rope can reach; a measuring winch motor which can turn the measuring winch drum to wind in or out the measuring line; means for attaching the outer extremity of the measuring line, away from the drum, to the load to be lifted by the crane; first transducer means operated by the measuring winch to provide a displacement signal proportional to any change, in relation to a predetermined value, and having regard to sign, of the length of measuring line extending from the measuring winch drum to the load; and crane motor control means operable by the displacement signal to control the crane motor to haul in or let out the crane rope substantially in synchronis

Abstract: A self-regulating, fast-response fuel vaporizer is disclosed which is cape of promoting increased efficiency of combustion of the fuel supplied to a spark ignition engine throughout the entire working range of the engine. The vaporizer comprises an inlet conduit through which fuel-air mixture is admissible to the engine, the mixture being directly heated within the conduit by an exhaust conduit which intersects with the inlet conduit. Use is made in the design of the respective heat transfer surfaces, of an inherent effect that flow pulsations have upon heat transference between a gas flowing in a tube and the walls of that tube, to provide a selected inverse relationship between heat transfer coefficient and engine speed whereby automatic regulation may be achieved of the heat supplied to the fuel-air mixture for all engine speeds.

Abstract: The invention provides a hydraulically-driven reciprocatory tool comprising piston with a shoulder reciprocable in a cylinder, and a shuttle valve for controlling supply of fluid to a first face of the piston, the fluid producing a force on the first face which is alternately greater than and less than a constant bias force applied to a second face of the piston, wherein the position of the shuttle valve is determined by the pressure of fluid in a fluid connection between the shuttle valve and first and second ports in the wall of the cylinder, the fluid connection including a first non-return valve for preventing flow of fluid from one of the ports to the shuttle valve and a second non-return valve for preventing flow of fluid from the shuttle valve to the other of the ports. Preferably, each non-return valve has associated with it a variable throttle in the fluid connection and further means are provided for controllable flow of fluid along a branch of the fluid connection.

Abstract: The apparatus includes a scanning system for scanning a projected image of an axially symmetric component's profile in a plurality of lines of scan, each line of scan being transverse to the axis of symmetry of the components profile and having a predetermined spatial relationship with respect to a neighboring line of scan. The scanning system may include a linear or two dimensional array of image detectors and the system produces electrical signals representative of the extent of the image of the component's profile along each line of scan for processing by a computer which uses these signals to calculate at least one of the parameters of length, breadth and curvature of the axis of at least a portion of the component and determines whether the parameter lies within a predetermined range.

Abstract: A fluid flowmeter of the venturi type is disclosed in which a throat is fed between complementary surfaces of a duct and a control member. Relative movement between the duct and the control member in response to the flow of fluid through the meter serves to enlarge the throat as the flow rate increases, and operation over a wide range of flowrates is thereby made possible. A measure of fluid flowrate can be obtained from fluid pressure measurements at the throat and at a position upstream thereof. An advantage over one prior art device is that the throat position remains substantially constant during relative movement of the complementary surfaces, so that sensing of the throat pressure is simplified.

Abstract: A fluid flow restrictor is described having a long path length capable of sorbing energy with less noise generation than that normally encountered with conventional fluid flow restrictors of short path lengths. The restrictor is adapted for attachment between two adjacent lengths of a pipeline, three forms being particularly described, one of fixed path length and bore, another of fixed path length and variable bore, and a third of variable path length and fixed bore.

Abstract: Impregnation of a porous carbon body involving deposition of carbon from a as can be effected by establishing a thermal gradient across the body such that carbon is deposited at a boundary which advances through the body. The present furnace is for use in such a process and comprises a heater element with which, in use, the body is in contact and a cooled surface facing the element, characterized in that the latter surface is covered with a layer of thermal insulating material to reduce the thermal gradient across the body. This improves the economy of the process. The insulating material is suitably fibrous, eg graphite felt, and is protected by a layer of relatively low permeability, eg graphite sheet, to prevent deposition of carbon which would reduce its insulation properties.

Abstract: A self burying anchor of invert conical construction having an apex fluidng water outlet and compressed air outlets close to the apex. The fluidizing water in conjunction with the compressed air, which expands in the confines of undisturbed bed material, bury the anchor beneath the fluidizing bed material. The anchor cone may be hollow and perforate so that fluidizing bed material is deposited inside to act as ballast.