Abstract: An orthodontic bracket comprises a bracket body with a mesial distal extending arch wire slot and a ligating latch spring member having the form of a thin flat metal strip. The spring member comprises along its length, in the order stated, an anchor portion anchored in the bracket body, a flexing portion in which the majority of the flexing takes place, a ligating portion that closes the slot mouth and engages any arch wire therein, and a latching portion by which the spring member is latched to the bracket body. The spring member may comprise a biasing portion between the flexing and ligating portions at the slot occlusal surface, or between the ligating and latching portions at the slot gingival surface, this biasing portion being convex toward the slot lingual wall and protruding into the slot to press the arch wire into the respective slot wall junction for more precise control.

Abstract: A refrigeration system has a compressor operable to supply compressed refrigerant vapor, a condenser to liquify compressed refrigerant vapour from the compressor, a thermostatic expansion valve to vaporize liquified refrigerant from the condenser, an evaporator to cool the surrounding atmosphere by vaporized refrigerant from the thermostatic expansion valve, a superheat sensor to improve control of the thermostatic expansion valve, a compressor discharge line to convey compressed refrigerant vapour from the compressor to the condenser, a return line to convey liquified refrigerant from the condenser to the expansion valve, and a suction line including the superheat sensor to convey vaporized refrigerant from the evaporator to the compressor.

Abstract: A stretcher for immobilizing a patient or casualty has a wrap-around flexible sheet member with a longitudinally extending medial portion positionable under a patient or casualty and side panel portions extending laterally outwardly from opposite sides of the medial portion. One side panel portion is foldable across the top of a patient or casualty and the other side panel portion is foldable across the top of the patient or casualty and the top of the one side panel portion. Each side panel portion has at least one slit which is substantially vertically aligned with a corresponding slit in the other side panel portion, when the side panel portions are folded across the top of a patient or casualty, to provide access to the patient or casualty through the aligned slits. Longitudinally spaced adjustable fastening devices are provided to secure the other side panel portion in place across the top of the patient and the one other side panel portion.

Abstract: The invention provides a stand for sheet music which includes a music support having a platen for carrying the music, a telescopic post for adjusting the height of the platen, and a base supporting the post and having collapsible legs. The post and music support are coupled to one another such that the support can be tilted relative to the post so that the music can be displayed at various heights and at various angles to the vertical. The music support is collapsible for movement between a deployed position and a stored position to minimize the size of the music support for transporting the stand.

Abstract: An annular co-extrusion die for extruding multi-layer tubular plastic film has inner die members stacked one upon another. The inner die members have radially outwardly extending surfaces forming radially outwardly extending helical passages between respective pairs of die members. An annular outer die member surrounds the stacked inner die members and forms a longitudinally extending annular passage therebetween for conveying plastic material from the radially outwardly extending helical passages to an annular extrusion orifice. Each inner die member forms with an adjacent die member a first feed passage extending at least partly around the inner die member radially inwardly of the helical passages, the inner die member and the adjacent die member having a circumferentially extending clearance therebetween to enable plastic material fed into the first feed passage to pass through the clearance into the helical passages.

Abstract: An orthodontic bracket comprises a bracket body with a mesial distal extending arch wire slot and a two-armed ligating latch spring member mounted thereon. The two arms comprise a ligating inner portion and a latching outer portion joined by a connecting portion and the spring member is movable between an unlatched slot open position and a latched slot closed position in which the slot is closed by the ligating portion and the spring member is latched to the bracket body by the latching portion. The bracket body may be made as two mirror image parts between which the spring member is mounted, the two body parts thereafter being fastened together. Each body part may carry a cylindrical mesial distal extending pivot post, the spring member being mounted on the posts for pivoting movement relative to the bracket body, the posts and spring member being frictionally engaged as it moves between slot open and closed positions for frictional damping of the pivoting movement.

Abstract: A method of mounting narrower paper rolls for unwinding on a pair of stub chucks spaced for mounting and unwinding full width paper rolls and carried by arms of a pair of multiple reel stands includes providing a narrower paper roll wound on a tubular core assembly having a hollow cylindrical core member and an annular end member of metal or plastic within each opposite end portion of the core member. The end members are removed from the core member, and the core member is mounted at a desired longitudinal location on a full length shaft having opposite ends engageable with the stub chucks. Core member engaging devices are provided to enable the core member to be secured in the desired longitudinal location and to transmit rotational torque from the shaft to the core member. The full length shaft with the narrower paper roll thereon is then mounted on the stub chucks.

Abstract: An annular clamping flange for use in clamping a first pipe end portion to a second pipe end portion in an engine exhaust system, has first and second arcuate flange portions co-operable to form a pipe receiving aperture, each flange portion having at least one clamping bolt receiving aperture with a longitudinal axis parallel to the longitudinal axis of the pipe receiving aperture. The annular flange having an outer periphery of generally parallelogram shape with a pair of opposed acute angles and a pair of opposed obtuse angles, the parallelogram shape having rounded corners, one flange portion providing one side and portions of sides of the parallelogram shape adjacent thereto, and the other flange portion providing the opposite side to said one side and the other portions of said adjacent sides, each flange portion having a connecting bolt receiving tubular lug on each said adjacent side portion thereof.

Abstract: A self ligating orthodontic bracket comprising a U-shaped ligating spring member movable between slot open and closed positions on the bracket body is adapted for reception of an additional external ligating member, such as an elastomeric hoop or loop, by providing the spring member in its occlusal portion at least adjacent its junction with the lingual portion with a mesial distal extending spring slot in which the additional ligature is received and securely retained, the slot opening at least partly lingually and being convex in the labial gingival direction; preferably the slot opens both occlusally and lingually. Preferably also the gingival surface of the bracket body is provided with a mesial distal extending gingivally-opening body slot, convex in the occlusal direction, for reception and retention of an external additional ligating wire or elastomeric hoop engaged in the spring slot.

Abstract: A method of recovering metals and producing a secondary slag from base metal smelter slag produced by a copper or nickel smelter includes mixing the smelter slag with at least one reducing agent selected from the group consisting of carbon and aluminum, said carbon (if present) being from about 1% to about 10% by weight of the slag and said aluminum (if present) being from about 5 to about 30% by weight of the slag, and with from zero to about 60% calcium oxide by weight of the slag. The mixture is heated above the eutectic melting point thereof directly and to ignition temperature aluminothermically (if aluminum is present as reducing agent) to reduce the iron silicate to ferrosilicon containing substantially all the copper, nickel and cobalt which was in the smelter slag and form a secondary slag comprising at least one compound selected from the group consisting of calcium silicate, calcium aluminate and calcium iron aluminum silicate. The ferrosilicon is then separated from the secondary slag.

Abstract: The invention provides a saddle support for use on a bicycle frame having a tubular upright with an exposed open upper end to receive the support. A tubular post is proportioned to slidably engage in the tubular upright and a clamp is coupled to a first end of the post for engagement inside the upright. The clamp includes an actuator inside the post for operation to releasably clamp the post in the upright and a saddle coupling is attached to the other end of the post. The coupling includes a base attached to the post and a top coupled to the base and adapted to be attached to a saddle. The top is moveable between a closed position where the top bars access into the post, and an open position where the top permits access into the post for a tool to operate the clamp. A lock is coupled to both the base and to the top to retain the top in the closed position to prevent unauthorized access into the post to release the clamp. The lock is operable to release the top for movement into the open position.

Abstract: An optical instrument comprising a housing having an optical path and a lens turret carrying at least two different optical components. At least three supporting devices are carried by the housing and engage the outer cylindrical wall of the lens turret at circumferentially spaced positions to support the turret for rotation about the longitudinal axis of the outer cylindrical wall to position a selected optical component in the optical path. Rotation of the turret is effected by a motor with a rotatable output pulley and a flexible drive element passing around the pulley and the outer cylindrical wall of the turret. One of the optical components is a rearwardly facing mirror, and the turret has a relatively large open area to enable light to pass therethrough for reflection by a mirror on the housing to the rearwardly facing mirror.

Abstract: An annular end member of plastic material for insertion into an end portion of a hollow cylindrical core member of a tubular core assembly for a roll of paper or other sheet material has an outer annular surface securable to an inner annular surface of the core member and an inner annular surface shaped to receive a roll supporting chuck. A radially-projecting lug adjacent an end of the end member is engageable in a lug-receiving notch in the core member, and a plurality of circumferentially-spaced axially-extending channels are provided in the inner annular surface of the end member to receive radially outwardly movable portions of a chuck. The channels have side walls engageable by the radially moveable chuck portions to enable rotational movement of the chuck to be transmitted to the end member. The end member can be constructed so as to be a universal fit on various different types of chuck.

Abstract: A piston and cylinder assembly for a gas powered gun, has a cylinder containing a piston rod slidably movable between a loading position in which the leading end of the piston rod is in a withdrawn position, and a firing position in which the piston rod has moved forwardly. The cylinder has first and second chambers through which the piston rod extends, the cylinder being connectable to a pressurized gas supply supplying pressurized gas to the first chamber when the piston rod is in the loading position. The piston rod permits communication between the pressurized gas supply and the first chamber and prevents communication between the first and second chambers when in the loading position, and when in the firing position prevents communication between the pressurized gas supply and the first chamber and permits communication between the first chamber and the second chamber to cause pressurized gas in the first chamber to pass into the second chamber.

Abstract: The invention provides a wall stop or spacer which is mounted on the hospital bed and impinges on the skirting of the wall near the floor should the bed be pushed towards the wall with resulting impact. Also, because the engagement is usually at right angles to the wall, the spacer has a width greater than the distance between the studs in the wall so that the load will be distributed across the studs. Further, because the impact is on the skirting, the impact takes place at one of the strongest pans of the wall where the wall plate and studs meet and the skirting passes over these pans to further reinforce the structure. The wall stop can be placed in a deployed position for engagement with the skirting or manually moved into a stored position under the bed to permit an attendant to walk behind the bed when the bed is moved from room to room.

Abstract: The invention provides a side rail assembly for use with an institutional bed. The assembly includes provision to move a vertical frame from an upper or deployed position where it is generally above the mattress on the bed, to a lowered position generally below and outside the mattress. The frame can then be moved longitudinally from the lowered position into a stored position below the mattress so that the frame will not interfere with an attendant who is assisting the patient. Further, the frame will then have no impact on access to the bed. The side rail assembly also includes a balance assembly to counterbalance the weight of the frame so that the frame is unlikely to cause accidental injury to a patient as the frame is moved vertically.

Abstract: A utility knife has a blade magazine removably mounted in a manually holdable housing and rotatable about an axis parallel to a longitudinal axis of the housing. The blade magazine has a series of radially and longitudinally extending circumferentially spaced blade-receiving slots for separately receiving thin blades having a cutting edge at at least one end thereof, each slot having an open front end to enable a blade therein to be removed from the magazine by forward movement through the front end of the slot. The housing also carries a slidable transport mechanism having a manually engageable actuator projecting from the housing and slidable in a longitudinal direction between front and rear positions, the transport mechanism also having a blade-engaging arm within the housing.

Abstract: A folding table has a table top with an upper working surface and an underside, the underside having at least one rearwardly located leg retainer and at least one forwardly located strut retainer. A leg assembly has an elongated connecting member and a pair of legs extending from opposite ends of the connecting member, each leg having a foot member extending from a lower end thereof remote from the connecting member. An angularly movable strut is pivotally secured at the rear to at least one of the legs and is releasably engageable at the front with the strut retainer. The strut is angularly movable between a working position in releasable engagement with the strut retainer to maintain the tabletop in a working position and a retracted position between the legs when released from the strut retainer.