Abstract: An orthodontic bracket or convertible buccal tube for use with arch wires has the usual mesial distal extending slot having one side open to receive the wire. The open side is closed by a shutter pivoting on a pivot pin, or coaxial pins, about a mesial distal axis, the shutter being latched in slot closed position to retain the arch wire in the slot. The device includes an attitude controlling spring member consisting of an integral extension of the part of the shutter member that closes the slot, the extension being thinner and therefore of greater flexibility than the relatively rigid shutter member. The extension can be progressively thinner that the shutter member from its junction therewith to a free end that engages the arch wire in the slot. In slot closed position a portion of the integral extension is positively engaged with a surface of the device body so as to preload the spring.

Abstract: An orthodontic bracket or convertible buccal tube for use with arch wires has the usual mesial distal extending slot having one side open to receive the wire. The open side is closed by a shutter pivoting on a pivot pin, or coaxial pins, about a mesial distal axis, the shutter being latched in slot closed position to retain the arch wire by a latch having one latch member on the pivot pin/s and a cooperating member on an annular part of the shutter surrounding the pin/s. Preferably the latch members are a mesial distal extending cam shaped recess in the pivot pin/s and a projection protruding from the annular shutter part, or vice versa. The part of the annular shutter part carrying the latch member is made flexible by a mesial distal extending through slot dividing it to form a movable segment of about 200° to 270° of the total circumference; a tool can be inserted into the slot to assist in disengaging the latch.

Abstract: Molten metal inclusion sensor probes have a sensing passage through which the molten metal passes, while direct current passes through the passage between two electrodes. The passage of an inclusion through the passage changes the resistance in the path, resulting in a pulse indicating its size, and enabling the number of particles in a sample to be counted. Previously the passage has been cylindrical, with or without a conical entrance, or of randomly smoothed profile produced by melting the probe material. High levels of background noise make pulse detection difficult, and operation is improved by the passage decreasing smoothly in cross-section in the flow direction, preferably with a parabolic or elliptical profile, and preferably with the exit of the same profile. The wall surface is formed to a smoothness of better than 1.016 micrometers (40 microinches), preferably 0.254 micrometers (10 microinches), permitting pre-determination of the optimum testing and conditioning currents required.

Abstract: A new structure is provided for orthodontic devices comprising a bracket or a convertible buccal tube, both of which have a body with a mesial-distal extending arch wire receiving slot therein. Both have a slot closure member, also referred to as a jamming shutter, pivotally mounted by the body for movement between slot open and closed positions and consisting of a pivot portion including an arm portion with a mesially-distally extending slot closure portion at its end. The slot closure portion has a part that closes the slot and mesially-distally extending parts that in the slot closed position engage an adjacent body surface with an interference jamming fit sufficient to retain the slot closure member in slot closed position. Any movement of the slot closure member to and from the slot closed position involves flexing of these engaged parts away from the device body against the elasticity of the material, removing the need for latches or retaining springs.

Abstract: A toe box protector, or a metatarsal protector, or a combined protector for safety footwear are molded from plastics material either integrally or as separate parts. Each protector part comprises a body of generally U-shaped cross section provided at the central part of its top outer surface with a force receiving part that overlies the central part with its lower surface spaced from the central part and of concave shape toward the central part, thereby forming an arcuate air space at this location. In an integrally molded structure each force receiving part has two transversely spaced integral junctions with the respective body; alternatively they are molded separately and the force receiving part has longitudinal edges that engage two mutually facing, spaced surfaces on the body part.

Abstract: A metatarsal protector for footwear consists of a body molded from resilient plastics material, thus facilitating walking and kneeling, the material being sufficiently flexible that it can be molded flat and bent to the required saddle shape when it is incorporated into the footwear close against the upper inner surface. The range of hardness required for the material is comparatively narrow, so that it is sufficiently flexible, but can still meet certification requirements, and as measured by a Durometer A test is between 35 and 50 Shore. The protector comprises a plurality of integral ridged projections protruding from one surface, forming between themselves a corresponding plurality of open-mouthed recesses, each of which is surrounded by a single projection (e.g. giving a circular recess) or by a plurality thereof intersecting one another (e.g. giving rectangular or triangular recesses). When an impact force is applied to the metatarsal region the resilient material deforms and absorbs the force.

Abstract: The invention provides a new automotive tractor unit for use with a new semi-trailer unit to form a rigidly-coupled tractor/semi-trailer combination. The tractor has a long wheel base and has its fifth wheel assembly mounted for extended longitudinal movement between a receiving position at its rear end and a mounting position close to the driver's cab. The tractor and semi-trailer chassis frames cooperate with one another to permit pitching between them while preventing yaw between them. The semi-trailer has a retractable landing gear movable beneath the chassis between a forward position close to the king pin to support the semi-trailer front end in the absence of the tractor, and a rear position close to the running wheels so that the semi-trailer can rest on the tractor and be rigidly coupled thereto. Preferably the tractor wheel base is of length from 6.8 meters (22 feet) to 8.5 meters (28 feet), while the fifth wheel assembly is mounted for a longitudinal movement of from 4.8 meters (16 feet) to 6.

Abstract: An attachment assembly provides a secure attachment point for the fall arrest tether lines of safety harnesses of workers on flat roofs, the assembly being movable over the roof as required. The assembly can be used alone, but usually is mounted on a wheeled utility cart as employed by roofers to move materials on the roof, or may be an integral part of such a cart. The assembly has a base frame that is spaced from the roof edge over which the worker may fall. An attachment member for tether lines is mounted on the base frame together with at least two longitudinally spaced surface engaging arm, the arms being located at the frame side nearer to the roof edge. When the assembly is in operative position each arm has its lower end, which usually has teeth, close to the roof surface. A counterweight is mounted on the opposite side of the base frame.

Abstract: A method of testing a product for the detection of the presence therein of a defect such as a void or an inclusion, comprises cutting the product and examining the resultant noise for the presence therein of an acoustic component representative of the presence of the inclusion. The method is applied to the processing of metal into slabs, bars, rods, wire strip etc., where the ends must be cropped to remove defective material, specifically to the continuous processing of strip metal where metal strips are joined continuously end-to-end, and where the ends of each strip as rolled may include undesired inclusions such as slag. A leading end piece is cropped by a shear, and the cropping of such pieces is continued until the testing method shows that the material at the place of the cut is free of the undesired inclusions.

Abstract: A melt dispersible, floatable, solid additive for molten metal comprises an elongated body of the additive with a band or bands of a thermal barrier providing material therearound which is preferably heat decomposable and gas evolving at the temperature of the molten metal. When the additive is dropped or released and urged forcibly into the molten metal the formation of a solid casing of the molten metal on the body at the position of the band or bands is retarded so that melted additive is released at the position of the band or bands and the body separates into discrete parts thereby rapidly releasing the additive into the molten metal.

Abstract: In a new spraying apparatus a spray boom structure supporting the spray dispensers for liquid or finely divided spray material is supported by an air pressured flexible bag skirt attached to the structure and forming an enclosure into which the spray dispensers discharge to minimize drift of the sprayed material and permitting increased speed of the apparatus over the ground. The bag skirt structure also "averages out" irregularities in the surface so that a more uniform spray pattern is achieved. Air is fed into the enclosure from the leading bag skirt part via an elongated aperture close to the ground and from the trailing bag skirt part from an elongated aperture close to the enclosure roof. The weight of the fan and its housing supplying the pressurized air is supported separately from the boom. The boom structure may comprise hinged portions that can be moved to a vertical storage position, and it may also include arcuate downwardly extending support members.

Abstract: A seal plug for conduits is disclosed having a plug core including at least one radially-expansible seal member for sealing the conduit in which it is disposed, while permitting passage of cables or the like therethrough. Until required for the cable or cables, the passages in the seal plug are closed by removable pin inserts, retainer means being provided to hold the inserts in place. The plug includes longitudinal compression means to bring the seal member into sealing contact with the conduit wall. Each passage may open to the circumference of the respective seal member via slits to permit sideways insertion of the cable therein.

Abstract: An apparatus for playing a bicycle game, and forming part of or attached to a bicycle or similar vehicle, can release a plug or similar object, so as to drop the plug at a target on the ground. Actuation for release of the plug is carried out by the rider. The apparatus also includes an indicator means such as a trailing line, for temporary detachment by a pursuer, and this action can also release the plug. The game can be carried out by a single rider and in games of pursuit by teams each comprising several riders.

Abstract: A multislide holder and editor comprises a rectangular plate-like body having a plurality of rectangular slide-receiving pockets formed between two sets of parallel ribs disposed at right angles to one another. Upon insertion into its respective pocket each slide enters two spaced parallel open-ended side edge engaging channels, each channel comprising two spaced edge-engaging members. One of these edge engaging members comprises at least two longitudinally spaced portions with a gap between them, while the other cooperating member is disposed opposite this gap and is of not greater length than the gap, so that the entire body can be formed by a single molding operation with linearly-moving relatively simple mold parts.