Abstract: A gripper system for a programmable manipulator includes a gripper arm (10) and an assembly station for holding a finger element (2) releaseably for mounting on the arm. The finger element (2) is held by latches (21, 22) against a tray (20) of the station which can be displaced with respect to a rack plate (1) of the station. The arm is conditioned to move on a predetermined path with respect to the station so that cooperative parts (3, 11) of the arm and a finger element, held at the station, become inter-engaged. When the finger element and the arm are inter-engaged movement of the arm relative to the station causes the finger element to be released. The gripper comprises an arm and a finger element dedicated to a specific handling task. The arm and the finger element have cooperable parts which are inter-engageable to mount the finger element detachably on the arm.

Abstract: During demonstration of a job sequence by an operator, an image error signal generated by a camera raster, is fed into a register, where it corrects the actual raster position, which is then stored in a data store. A tachometer signal from a joint of a model of a robot arm being manipulated by the operator is subtracted from a corresponding tachometer signal on the robot arm and passed to a processor.The processor uses an iterative procedure to evaluate a set of constants from the tachometer signals from the model. The servo signals are subsequently used to enable the robot arm to repeat the job sequence.

Abstract: Disclosed are x-ray machines using fan-beams of x-rays to examine sectional slices of patients and to form detailed x-ray pictures of such slices, and methods of so examining patient slices. A source of a fan-beam of x-radiation, and a system detecting the radiation after it passes through a slice of the patient, rotate around the patient.

Abstract: A damped inertia roller for reducing tape flutter in a magnetic tape transport comprises an outer cylindrical hollow shell which encloses a centrally bored cylindrical flywheel rotatably mounted about an axial shaft. The shaft is rigidly fixed to a closed end face of the hollow shell, and a resilient damping washer is sandwiched between an end of the flywheel and the closed end face of the shell. A second resilient damping washer is sandwiched between the other end of the flywheel and a disc shaped retaining member. The shaft is recessed within the flywheel bore, and has a threaded axial hole in its recessed end face.A retaining screw passing through the retaining member and the second washer is threaded into this axial hole, and adjustment of its tightness provides a means of adjustably compressing the washers to control the damping of the roller.

Abstract: A sensing apparatus has a probe displacement with respect to a support arm and to a reference position. The probe has a flat disc mounting three transducers which are spaced apart from one another at regular intervals. Each transducer has an elastomeric dielectric and is capable of producing an electrical output signal in response to displacement of the probe from the reference position. An electrical circuit compares output signals produced by the transducers and evaluates the direction and/or extent of probe displacement. Such evaluation may be used in the manipulator control system of an article-handling equipment.

Abstract: A linear filament assembly for a halogen cycle or other incandescent lamp comprises a generally linear filament usually a coil or coiled coil, supported at opposite ends by substantially rigid conductive leads. A rigid insulating rod, preferably of quartz extends generally parallel to the filament, and a plurality of supports extend between the rod and the filament, each support being fixedly secured to the rod and supporting the filament. The supports are embedded in the rod, this being achieved by heating the rod at the point of insertion until it is sufficiently soft to insert the wire without excessively distorting the rod.

Abstract: A sensor array includes a number of discrete elements each comprising a dielectric body and two electrodes. Dielectric body has an annular skirt and the electrodes define an annular gap in which an end portion of the skirt is located. Body is displaced relative to the electrodes upon application of pressure thereto, causing the skirt to further penetrate the gap and cause a detectable change in capacitance of the electrodes, related to the magnitude of the applied pressure. The dielectric bodies are supported by a common, resilient sheet which returns the bodies to a rest position when pressure is removed.

Abstract: A clock circuit is initiated by an external trigger pulse. Timing measurements commence at a first rate, and after a first delay (t.sub.1) which is sufficient to allow an oscillator of the clock circuit to stabilize. After a second delay (t.sub.1) the clock circuit operates at a second rate which is half the first rate. The clock circuit then represents the time from reception of the external trigger pulse. The first and second delays are derived by charging a capacitor at a constant rate and comparing the voltage level developed across it with respective reference voltages (V.sub.1, V.sub.2) in comparators.In general, the second rate may be 1/r+1 times the first rate, where r is the ratio of the first delay to the second delay.

Abstract: A junction field effect transistor has a substrate forming a junction with a layer of semiconductor material which has a gate, a source and a drain therein. The thickness of the n-type layer underlying the source is substantially greater than that underlying the gate (for example the ratio of n-thickness below the gate to that below the source is 1 to 2.53) in order to reduce the parasitic resistance as compared to conventional JFETs.

Abstract: A magnetic powder core, suitable for use in a low frequency power device, is prepared by a method including the steps of coating an atomized iron powder from an aqueous solution of potassium dichromate, drying the powder, compressing the powder to form a compact and heat treating the compact until it becomes partially sintered. Cores having coercivities below 240.sup.A /m, saturation inductions exceeding 1.3 Tesla and resistivities exceeding 500 microhm cm are disclosed.

Abstract: A permanently structured magnetic recording tape includes a pattern of first and second regions of acicular iron oxide particles, the first `A` regions being orientated at 22.5.degree. (clockwise) to the tapes axis and the second `B` regions being orientated at 67.5.degree. (clockwise) to the tape axis. A permanent magnet applies a developing field at 45.degree. (anti-clockwise) to the tape axis such that, at the transition in orientation direction, the normal components of remanence in `A` and `B` regions are in opposite directions, thereby increasing pole strength at the transitions compared with longitudinal development, and enhancing the output signal at the magnetoresistive read-out transducer.A second magnetoresistive transducer senses fluctuations in magnetic polarity at the tape edge to verify whether the medium is genuine.

Abstract: An arc discharge lamp is provided using sealing compositions comprising mainly Al.sub.2 O.sub.3 --SiO.sub.2 --MgO. Preferred compositions include between 25 to 28% by weight of MgO and 13 to 21% by weight of Al.sub.2 O.sub.3 since these have lower melting points than others in the group. Additives of B.sub.2 O.sub.3, nucleating agents and HfO.sub.2 and other rare earth oxides are preferred. The sealing compositions are used to seal end closure members of alumina or CERMET to ceramic arc tubes for use in discharge lamps. The compositions are selected to have linear expansion co-efficients compatible with the materials of the end closures and arc tubes. The methods described give scaling times of between 3 and 4 minutes.

Abstract: A strain sensing arrangement includes a rigid annular ring, which is co-axial with an upper central boss and a lower central boss. An upper array of vertical, relatively flat, wide and flexible beams are connected to the upper boss and the ring and a lower array of horizontal beams are connected to the lower boss and the ring. Each of the beams are provided with a strain gauge on each side thereof for detecting any deflection of the beams.When the arrangement is utilized in an assembly robot, the end of an arm of the robot is inserted downwardly into the upper boss and a gripper is inserted upwardly into the lower boss, so that the strain gauges can detect torsional and/or linear strain acting on the arrangement caused by relative rotation of the gripper with respect to the arm.

Abstract: A radiographic apparatus contains at least one source and at least one detector bank mounted on respective concentric annular rings; the patient's body being disposed inside the smaller ring. The rings are rotated in opposite directions and at such respective angular velocities that the effect of a lateral sweep of the detectors and source across the body is achieved with purely rotational movements. Advantageously, one ring carries two sources disposed diametrically opposite one another and the other ring carries three banks of detectors distributed equi-angularly therearound.

Abstract: A tactile array sensor comprises an array of substantially parallel row conductors disposed upon an alumina substrate. An array of substantially parallel column conductors overlies the array of row conductors and a layer of insulative material is disposed between the row conductors and the column conductors. A conductive rubber sheet overlies the column conductors. A multiplexing circuit addresses the row and column conductors and, when an object is in contact with an area of the conductive sheet, the circuit generates output signals indicative of all crossing points within the area, due to electrical contact being made between the row and column conductors via the conductive sheet.

Abstract: A magnetic field gradiometer includes a pair of coils, encompassing different regions of space. A SQUID is provided to detect a difference in flux linking the coils thereby to provide a measure of a magnetic field gradient between the coils. A control element of a superconducting material is provided in the vicinity of the coils and a heater is controlled to vary the proportion of the element assuming the superconducting state. By suitably varying this proportion the balance condition of the coils can be altered. The control element may operate in a feed back circuit. A coil subjects both coils to an alternating magnetic field at a preset frequency. A component in the output of the SQUID having this frequency is used to control the heater.

Abstract: In order to initiate a low explosive (pyrotechnic) mixture with a high explosive detonator, a metal diaphragm preferably of aluminium alloy is interposed between the detonator and the mixture. The diaphragm interacts with the detonation wave so that it initiates the composition.

Abstract: A system capable of unbuffered transfer of magnetic tape between a take-up reel and supply reel comprises a control unit connected through a mode switching device to a respective linked error device and pulse width modulator, arranged to drive a respective take-up or supply reel motor. A tachometer monitors the amount of a pre-determined length of supply spool tape transferred to the take-up spool and the control unit accordingly evaluates proposed reel motor current levels. The mode switching device operates each motor in velocity or acceleration mode. In the velocity mode a phase locked loop connected to the tachometer and a control frequency output provides an error signal which can be applied to the selected motor current level. In the acceleration mode a motor current sensor output is compared with the proposed current level to derive another error signal which can be applied to the selected current level.

Abstract: A sensing element suitable for sensing two components h.sub.x and h.sub.y of an external magnetic field in an orthogonal co-ordinate system comprises a reverse C-shape first electrical conductor vacuum deposited onto an electrical insulating substrate. A layer of photoresist applied to a region insulates the conductor from a magnetoresistive element which has two connectors linked thereto. Further application of photoresist insulates the element from a second vacuum deposited electrical conductor. Wires locate with respective conductors where gold deposition in the vicinity of the wire ends achieves electrical continuity. A control circuit applies current, within a periodic cycle, in alternate directions through the first conductor while a current is applied in a single direction through the second conductor. In the following cycle the current direction through the second conductor is reversed.