Abstract: A heat shield device suitable for use with a soldering device comprises a heat shield and means for moving the heat shield to and from the shielding position in which it shields a target area from a heat source, wherein the movement of the heat shield is mechanically linked to a movement of the heat source in relation to the target area. This device provides the advantage that the shielding of the heat source can be automatically synchronized with the movement of the heat source away from the target, the heat shield is secured with respect to the heat source by means of a resilient member which provides a biasing force to bias the heat shield away from the shielding position.

Abstract: A solder removing device is disclosed for absorbing solder which has been rendered molten by the application of heat, including an open-mesh structure comprising a strand and formed by knitting, as a primary example, at least the surface of the strand being metallic and receptive to solder flux (and indeed being coated with solder flux rendering it more capable of wetting with molten solder). The open-mesh structure enables the device to absorb solder more freely and in greater quantities than can prior braided devices in which the multiple strands are contiguous.

Abstract: A temperature responsive device, such as a fuse or a temperature measuring apparatus, is disclosed including a temperature sensor having a light reflective (or light transmissive) characteristic which varies with temperature, and a device for receiving the light reflected from (or transmitted through) the sensor and to provide an output in accordance with the state of the characteristic. As shown, the sensor (perhaps an adhesive temperature indicator) is used as a fuse and, upon its color-change, it interrupts a switch 2 connecting a power source to a load the temperature of which the sensor senses.

Abstract: An electrolysis apparatus is disclosed and comprises a plurality of cells connected in series both on the current flow path (an electrical course being connected across the end ones of the electrodes) and the electrolyte/gas flow path (electrolyte entering one end cell through one end electrode and gas issuing from the other end cell through the other end electrode), the cells including at least one series of gas generating cells followed by at least one cooling cell. The end electrodes of a series of cells may be short circuited so that these cells become cooling cells because they are not active to generate gas and instead the electrolyte and gas flowing through them undergoes cooling. The apparatus may be arranged for generating detonating gas or may be modified for generating oxygen and hydrogen at separate outlets.

Abstract: A solder removing device is disclosed including fibres of temperature-resistant non-metallic material, such as a synthetic polymeric material, for example FEP or PTFE, which are coated with a metal rendering them more receptive to solder flux. The metallized fibres are coated with solder flux rendering them more capable of wetting with molten solder, interstices between the fibres serving to absorb molten solder by capillary attraction.

Abstract: A floor mat apparatus comprises a length of synthetic plastic material having a high plasticizer content, and therefore having a tacky surface to collect dirt and bacteria, trained about rollers one of which is driven by a motor to bring fresh portions of the mat to the upper stretch between rollers across which people walk to a clean-room area. Portions of the mat leaving the upper stretch are washed and dried before returning to the upper stretch.

Abstract: An intruder alarm apparatus is disclosed for protecting a building or a vehicle and consuming a minimal amount of energy when in "watch" condition. An acoustic transmitter is placed inside (or outside) a closed space being supervised, an acoustic receiver is placed outside (or inside) the closed space, and an amplifier has its input connected to the receiver output and its output connected to the transmitter input. If the integrity of the closed space is broken, for example, the enclosing wall is breached, then an acoustic feedback loop is completed by a path being thus established between transmitter and receiver, such that oscillation occurs, and only now are substantial amounts of electrical energy consumed.

Abstract: Two receivers arranged inside and outside a closed space, respectively, are responsive to ambient or environmental noise and a comparator provides an alarm signal when the difference between the outputs of the two receivers falls below a threshold, thereby indicating that the wall to the space has been breached. Alternatively, the two receivers may be arranged in spaced relation within the space and the comparator provides the alarm signal when the difference between the two outputs rises above a threshold, thereby indicating that an intruder is present and closer to one receiver than the other. The apparatus consumes little energy during the watch period and does not depend on itself radiating energy.

Abstract: Apparatus and methods for testing the solderability of metal components and testing de-soldering wicks. The workpiece to be tested is lowered into a molten solder and upon contacting the solder an electrical circuit is completed to commence a timing cycle.

Abstract: A generator for oxyhydrogen gas comprises a plurality of flat metal electrodes mounted parallel with ring-like spacers between each pair of adjacent electrodes and bolts clamping the spacers and electrodes together to provide a sealed cell between each pair of electrodes within the periphery of the respective spacer. An inlet for electrolyte is connected to one outer cell and an outlet for the gas is connected to the outer cell. The electrodes are imperforate except for apertures adjacent the tops of the cells and in use a DC power source is connected across outer electrodes. The generator is of simple construction and achieves good cooling, high mechanical strength against internal explosions and ensures a minimal quantity of explosive gas in the upper regions of the cells.

Abstract: A package comprising a length of strand material in the form of a desoldering wick of braided wire having a coating of rosin thereon, a unitary annular body molded of plastic material including a central hub, first and second sides, and first and second continuous rims, the hub, sides and rims defining an annular chamber receiving therein the length of strand material in coil formation, the rims defining a continuous annular slot communicating with the outer periphery of the annular chamber of a size to permit the free end portion of the length of strand material in coil formation to extend therethrough in controllably engaged fashion.

Abstract: A device for removing a solder alloy from a solid soldered joint comprising a multiplicity of metallic strands formed into an elongated wick operable to effect the solder removal through the application of an end portion thereof to the joint in heat exchange relation to a heat source so that when the solder alloy is rendered molten by the heat source it will flow by capillary action from the joint into the applied end portion of the wick, the improved step of each metallic strand of the wick having its exterior surface coated with solidified solder alloy having a melting point substantially below the melting point of tin prior to being formed into the wick so that when the end portion thereof is applied to the joint in heat exchange relation with the heat source as aforesaid the solid solder alloy of the coating on the strands of the applied end portion when rendered molten by the heat source mixes with the molten solder alloy from the joint flowing by capillary action into the applied end portion of the wick

Abstract: A metal wick to be used for the absorption of molten solder is deoxidized and flux coated by a process that does not involve the application of heat to the wick or the flux. In one embodiment the wick is cleaned by heating in a reducing atmosphere and is then immersed in a coating bath containing a solution of a rosin flux in an organic solvent. On leaving the bath the welted wick enters a low-pressure chamber in which the solvent rapidly evaporates at room temperature. In another embodiment the deoxidized wick is coated with comminuted solid resin by electro-static means.

Abstract: A water decomposition apparatus for producing detonating gas or oxyhydrogen gas comprises a plurality of electrolytic cells formed between a nested plurality of endless laminar electrodes each sealingly abutting at its upper and lower edges against elastomeric insulating layers on the surfaces of rigid plates. Electrolyte circulation through the assembly is permitted by an inlet aperture in one extreme cell, an outlet aperture in the other extreme cell and an aperture in each intermediate electrode adjacent its upper edge. The inlet and outlet apertures are coupled for electrolyte circulation by immersing the assembly in electrolyte or by an extended duct system connecting the apertures. Current is supplied to the extreme inner and outer electrodes from a d.-c. source. Control means may be provided to reduce the magnitude of the current as the gas pressure rises. A plurality of assemblies may be connected electrically in series across the d.-c. supply.

Abstract: Intruder alarm apparatus includes two detector systems each responsive to the presence of an intruder within a portion at least of a protected area and alarm means responsive to the actuation of the detectors in a predetermined logic or time sequence for signalling the presence of an intruder. One embodiment includes two microwave Doppler detectors each responding to the presence of an intruder by opening alarm contacts. The two alarm contacts are connected in parallel in the loop circuit of a closed-loop alarm system so that an alarm is given only if both detector contacts are opened simultaneously. Preferably the duration of contact opening is arranged to extend beyond the period of actual intruder response.

Abstract: To supervise the integrity of an enclosed space one terminal of an ultrasonic transmission link is placed inside the space, and the other terminal outside, so that any breach of the walls enclosing the space causes an increase in the received ultrasonic intensity which initiates an alarm. The frequency used may be as low as 18 kHz. In an installation involving several supervised spaces, each space contains a receiver and a plurality of transmitters are outside all the spaces. Individual transmitters may emit coded radiation.

Abstract: A metal wick to be used for the absorption of molten solder is deoxidized and flux coated by a process that does not involve the application of heat to the wick or the flux. In one embodiment the wick is cleaned by heating in a reducing atmosphere and is then immersed in a coating bath containing a solution of a rosin flux in an organic solvent. On leaving the bath the welted wick enters a low-pressure chamber in which the solvent rapidly evaporates at room temperature. In another embodiment the deoxidized wick is coated with comminuted solid resin by electro-static means.

Abstract: In desoldering soldered joints, an electrically conductive wick or braid, used to absorb molten solder from the joint, is connected to a ground conductor of the circuit of which the joint forms a part, thus preventing possible damage to voltage-sensitive circuit components, for example FET's. A solder-absorbent conductive wick is provided with connecting means for connection either directly or through an intermediate conductor with a ground conductor of a circuit in which a joint is to be desoldered by the aid of the wick. Connection to the circuit conductor may be by way of a first electrical connector portion mating with a second connector portion on a circuit board carrying the circuit. The first connector portion may be mounted on a jig or locating fixture arranged to receive the circuit board.

Abstract: Damage to a frangible article, particularly a glass window is detected by sensors responsive to oscillations in different frequency bands. Only when all the sensors are simultaneously responsive is an alarm signal, denotive of damage to the article, developed. Piezo-ceramic transducers respond to frequencies within the range of 30 kHz to 1 MHz. The sensors are connected in parallel with inductors to provide resonant amplification of the voltage developed. The resultant signals are amplified and applied to an AND gate yielding the required output signal.

Abstract: A solder removing device is disclosed for absorbing solder which has been rendered molten by the application of heat, including an open-mesh structure comprising a strand and formed by knitting, as a primary example, at least the surface of the strand being metallic and receptive to solder flux (and indeed being coated with solder flux rendering it more capable of wetting with molten solder). The open-mesh structure enables the device to absorb solder more freely and in greater quantities than can prior braided devices in which the multiple strands are contiguous.