Abstract: A pressure loaded gear pump comprising a housing, a pair of intermeshing gears positioned in the housing, at least one gear side face sealing member, and pressure loading means for defining a pressure loaded area in use of the pump, the pressure loading means comprising a bobbin and first and second axial seals mounted on the bobbin.

Abstract: Liquid spray apparatus suitable for use in an electrostatic spraying system comprises a liquid supply duct, a conical surface at one end of the duct on to which the liquid is adapted to impinge and an annular nozzle for distributing the liquid after it has passed over the surface. Channels for imparting a swirling motion to the liquid are provided consisting of snail-shaped grooves formed in the conical disc or helical channels formed in the duct. A valve member is provided for varying the flow rate of the liquid through the apparatus.

Abstract: A telephone subscriber subset including a transducer for generating audible signalling tone information in which the signalling tones are received at the input terminal as substantially sinusoidal electrical waveforms and including a converter within the handset for conversion of the signalling tones to a substantially non-sinusoidal electrical waveforms before feeding to the transducer.

Abstract: An electrical connector consists of a cylindrical body having an internal one piece insulator in which a plurality of elongate male electrical contacts are secured. These contacts are adapted to engage female electrical contacts in another similar mating body in a tight fitting manner when the two bodies are secured together.The electrical contacts are cylindrical and provided with two spaced flange portions of larger diameter than the remainder of the contact, and the contacts fit into parallel cylindrical bores in the insulator, each bore having inwardly projecting protuberances which enter the space between the flange portions on the contacts. These protuberances are shaped to permit normal insertion of the contacts from one end of the insulator, and removal from the same end.

Abstract: A jammer transmitter having a comb spectrum generator which includes a pulse generator adapted to produce a pulse train at a frequency corresponding to the channel spacing of signals to be jammed, and a bandpass filter which has a passband including a bandwidth occupied by the signals to be jammed and which is responsive to the pulse train for providing within this bandwidth comb generator output signals at harmonics of the pulse train frequency, a power amplifier operative to amplify the comb generator output signals so as to produce jamming pulses and an aerial for radiating the jamming pulses, the width of the pulses of the pulse train being short enough to ensure that the harmonics of the pulse train frequency occur throughout the bandwidth.

Abstract: The divider is formed by a dividing counter 7 to which an input pulse train is fed via an OR gate 3. The counter 7 has a fixed division ratio and the OR gate is controlled by a logic circuit which receives control pulses and controls the OR gate to remove one pulse from the input pulse train for each control pulse in order to change the overall division ratio of the divider. The invention is particularly suitable as an adjustable ratio divider for use in frequency synthesizers.

Abstract: A data transmission system in which data is transmitted in a form incorporating additional data providing for error correction at the receiver. The data is encoded in a transmitter using a signal mapping system which maps a number of original digits and also digits produced by a convolutional encoder. The data at the receiver is decoded using hard and soft decision decoding which can correct errors in the received data.

Abstract: The invention relates to a connector arrangement for connecting two liquid supply ducts and at least two electrical leads. The connector arrangement comprises two abuttable bodies each having attachment means to a liquid supply duct and connections to the electrical leads and including a valve to close the liquid supply ducts. The electrical connection is made by an elongate conductor on one body entering a socket in the other body, this connection being made before the possibility of arcing between the electrical connections igniting the liquid.

Abstract: Each process in a multi-process computing system using so-called capabilities may have associated with it a process dumpstack protected by the capability mechanism. The functions of this dumpstack are (i) to provide the state of the process at the point at which it was suspended and (ii) to stack (or nest) information relating to the invoked procedures (i.e. sub-routines) of the process. Thus there is a fixed sized portion containing principally the machine registers, the indicators and the watchdog timer values and a variable sized portion containing information related to each nested procedure. Each stack link is of fixed size and contains three items:- relativized instruction address, the code block capability and process capability pointer list block capability.

Abstract: A method and apparatus for decoding received data signals using a Viterbi algorithm. To reduce the time required to decode a data signal, the system expands k received data vectors into nk vectors where n is smaller than m, m being the number of levels of the received data signal. Thereafter, k vectors are chosen from the nk expanded vectors and a "cost", defined herein is determined for each of said k vectors. The most likely identity of the received data signal is then determined on the basis of the computed costs.

Abstract: An electrical device package comprising an open ended container and an enclosure defining a cavity in which an electrical device is contained. The enclosure is positioned in the container and is sealed therein by a filling of moulding material.The package is particularly suitable for containing surface acoustic wave devices e.g. filters where contact with the moulding material during and after packaging must be avoided.

Abstract: The cathode ray tube assembly of a visual display unit is suspended over the static base in a cradle, the suspension pivots being as close as possible to the center of gravity of the moving section. Attached to the underside of the cradle is a bracket with forked arms. The forks engage with a spindle carrying a pair of friction pads and a helical compression spring. The spindle runs in a curved slot in a bracket attached to the static base. The friction pads are situated one on each side of the bracket and are maintained in intimate contact with it by the helical spring generating a friction force. Thus a force of sufficient magnitude applied to the moving part of the visual display unit will overcome the friction force and permit it to move, although normally the friction force will hold it in the required position.

Abstract: A hinge assembly for a lid for a container consists of a pivot pin secured to the lid and which is rotatably mounted at its end in recesses formed inside the container. The pivot pin is retained in the recesses by an abutment member formed inside the container, the abutment member being deflectable to permit the pivot pin to be inserted into or withdrawn from the recesses. The abutment member is moulded as part of the container and is shaped so that no movable cores are required for the moulding tool resulting in a low cost arrangement.

Abstract: The invention relates to fasteners for two parts of a body which are wholly contained within the body and not visible when the two parts are joined.The fastener comprises a resilient member secured inside the first part of the body projecting internally of the body and an orifice formed inside the second part of the body. The resilient member is shaped to enter the orifice and verge the two parts together and to permit separation of the two parts by a relative pivoting movement adjacent to the abutting joint between the parts whereby the resilient member is retracted from the orifice.

Abstract: A jet pump having a diffuser, a mixing section and a nozzle produced by electroforming onto at least one highly polished mandrel, whereby the diffuser, mixing section and nozzle have a surface finish of substantially the same quality as the mandrel.

Abstract: In a monitoring system for the gates of a mine lift shaft, each gate has a switch and a square wave is generated in a signal station and connected to a transistor inverter beyond each switch. When the switch is in the closed (safe) position, the transistor inverter is connected in circuit and the inverse of the waveform is transmitted back to the signal station. When the switch opens the transistor is shorted out and thus the returned waveform is in phase with the transmitted waveform. The various conditions which may be received at the signal station are detected and only if the switch and cable are operating correctly is the gate closed condition indicated. The use of a square wave and a changeover switch ensure that both conditions of the switch produce a definite signal at the signal station, thus any failure in the cable or switch prevents the received waveform from being the inverse of the transmitted waveform.