Abstract: A miniaturized thick-film isolation transformer comprising two rectangular substrates each carrying successive screen-printed thick-film layers of dielectric with spiral planar windings embedded therein. The spiral windings comprise conductors formed of fused conductive particles embedded within a layer of dielectric insulating means solidified by firing at high temperature to form a rigid structure with the windings hermetically sealed within the dielectric and conductively isolated from each other within the transformer. The substrates are formed at opposite ends thereof with closely adjacent connection pads all located at a single level to accommodate automated connection making. Connections between the pads and the windings are effected by conductors formed of fused conductive particles. The substrates and the dielectric layers are formed with a central opening in which is positioned the central leg of a three-legged solid magnetic core.

Abstract: In a new method of manufacturing eddy-current probes, particularly such probes for the scanning of a test surface generated by a non-flat profile, a thin, flexible support layer is laid against the test surface so that it conforms exactly thereto. One or more test coils have a sector thereof laid against the back face of the support layer so that the coil sector also conforms to the same profile in the plane of the coil and the profile. A plurality of separate ferrite core elements are now laid inside the loop of the coil, or the loops of the coils, and pressed against the coil so as to form a core that also conforms to the profile to be scanned. The remainder of the coil (or coils) is pressed against the backs of the ferrite elements and the assembly is encapsulated to make it rigid enough for mounting in a test apparatus for scanning over the surface to be tested. The front face of the support layer is the "active" surface of the probe and conforms precisely with the profile, since it was generated thereby.

Abstract: The heat exchanger frame is mounted on arcuate cradles on longitudinal rails so it may be angularly rotated and longitudinally moved, and locked in position. Each baffle is supported, and by preference the tube sheets are vertically adjustably supported. Adjacent one end of the heat exchanger frame a vertical way system is provided. On it a generally horizontal tube rack, is vertically adjustably mounted, as are a horizontally laterally movable way system and a worker-support platform. On the horizontal way system is provided at least one feed roll head. The feed roll head preferably has an automatically adjustable nip, is vertically counterbalanced for slight vertical self-adjustment, is reversible and incorporates a pusher piston for automatically pushing the trailing end of a tube being inserted the last couple of inches so as to clear the feed roll head.

Abstract: A contact array plate having a plurality of contact pieces arranged to extend between first and second coupling pieces is formed by punching of a sheet of metal. A first housing half is molded integrally with the contact array plate so that intermediate portions of the contact pieces are buried in the first housing half. Then the first and second coupling pieces are cut off to separate the contact pieces from one another and outwardly projecting portions of the contact pieces are bent along shaped sections of the peripheral surface of the first housing half to form contact propers. A second housing half acting as bending dies is assembled with the first housing half with the contact propers inside thereof to define therebetween an insertion opening for receiving a mating connector.

Abstract: A folding knife having a blade and a pair of folding handles. The handles are channel shaped and bifurcated at one end for receiving one end of the blade. The bifurcated ends of the handles are attached to the blades by adjacent pivot pins. Rotation of the handles to the closed position encloses the blade inside the opposing channels of the handles. The ends of the handles are coupled by meshing gears pivoted on the same pins so that the handles must rotate together in opposite directions through 180.degree. between closed and open positions.

Abstract: A generally cup shaped cutting head for fitting over and around the sprinker head includes a generally circular cutting edge for cutting around a sprinkler head, and a cleaning brush mounted concentrically within the cutting head and recessed from the cutting edge for engaging and cleaning the surface of a sprinkler head, with the cutting head detachably mounted on the end of an elongated drive shaft which is adapted to be driven by an electric drill motor or the like.

Abstract: A pair of tandem master cylinders have primary pressure spaces connected to the brakes on one pair of wheels on opposite sides of the vehicle, and an actuator for the brakes on a trailer is supplied with fluid under pressure from pipe-lines connected to each of the four pressure spaces and under the control of first and second disabler valves. Each disabler valve has a pair of inlet ports, each connected either to respective primary pressure spaces or respective secondary pressure spaces, and an outlet port connected to the actuator. When one master cylinder is operated on its own both disabler valves are closed to prevent the actuator from being operated. Failure of one pressure space, when both master cylinders are operated simultaneously, causes the corresponding disabler valve to close but the actuator can still be operated from the operative pressure spaces, through the other disabler valve.

Abstract: A plotter instrument for marking on a recording medium utilizes a rotatable pen carousel carrying a plurality of marking pen elements. A carriage drives the pen carousel into engagement with a cam track to produce rotation of the pen carousel and result in a change of the marking pen element in position for marking on the recording medium. The plotter instrument further includes drive rollers on a first driven shaft and pinch rollers on a second shaft, which shafts extend between opposing end plates. The drive rollers and pinch rollers are engagable with the recording medium for providing displacement thereof. Relative positioning of the drive and pinch rollers is provided by a pinch roller shaft cap eccentrically placed on each end of the second shaft. Each shaft cap is of a multi-sided, regular polygon configuration and insertable in a respective end plate opening. The orientation at which the cap is inserted determines the relative spacing between the drive rollers and the pinch rollers.

Abstract: An indicator (20) for a tape measure (10) is described. The indicator is marked with indicia (21) and arabic numerals (22) designating fractional increments between whole number measurements on the tape. In the preferred form the indicator is pivoted on the housing such as on pins 23 so the indicator can be folded adjacent the housing when not in use and can be unfolded and superimposed over the tape 12 when in use.

Abstract: A thread gauge which attaches to an inside micrometer to measure the thread pitch diameter of internally threaded parts. A pair of anvils have external threads which match in pitch with the threads of the part. Each anvil has a bore which receives a ball and a slot which receives a stem projecting from the ball. Mounting sleeves connect the stems with the opposite ends of the micrometer. Each anvil can rotate on its ball about the stem axis so that the micrometer can be adjusted to position the anvils against the threaded part. The anvils can also move linearly on the balls to properly align with the threads of the part.

Abstract: A touch sensor is disclosed which is capable of readily and precisely aligning the center of working shaft of a machine tool with that of a measuring element and allowing the distal end of the element to move in a wide range in the three-dimensional directions. The touch sensor includes a plurality of adjusting screws which extend through a casing and are forcedly pressed at one end thereof against a cylinder rotatably receiving a steel ball of the measuring element therein to remove a gap of a micro-distance between the cylinder and the steel ball formed during the assembling to render fine adjustment of the measuring element possible, to thereby precisely carry out the centering of the element.

Abstract: An angular measuring system consisting of one or more sensors that transmit angular measurements to a central control unit where numerical readout of any selected sensor is provided. A threshold can be preset at individual sensors or the control unit for an allowable angular deviation, beyond which a warning device is actuated. The circuitry permits locating the sensors remotely from the console and provides precision and stability of operation. Low power consumption permits extended operating periods with internal batteries. False alarms are minimized by incorporating a hysteresis loop in the threshold detection circuitry.

Abstract: A set of attachments which affix to a steel tape rule comprising a zero attachment which attaches adjacent to the zero end of the steel tape rule, and a case attachment which attaches to the case of the steel tape rule, and wherein the attachments each hold a scribing pin, commonly called trammel points, and wherein the zero attachment may additionally or in the alternatively hold a pencil or soapstone or chalk. The zero attachment affixes to the steel tape rule near the zero end of the steel tape rule, while the case attachment affixes to the case of the steel tape rule and when so attached provides for allowing the steel tape rule and the zero attachment to be extended from the case, and then the case attachment locks the steel tape rule in the extended position. Thus lofting, and measurements, as well as scribing arcs of substantial diameter are made easier and significantly faster, with no loss in accuracy.

Abstract: A dynamic alignment fixture which has a pivot plate which is adapted to h a rate gyro mounted thereon and a base which is adapted to be mounted on a rate table with means for adjusting the pivot plate relative to the base plate and rate table to allow for the testing of the amount of misalignment of an input axis of the rate gyro that is mounted thereon to allow misalignment data to be gathered on high-drift-rate gyros.

Abstract: A quantity of water deposited on sand particles is adjusted to a predetermined value by utilizing a method and apparatus disclosed having a hopper through which the sand particles to be treated are supplied. A velocity energy is imparted to the particles to project them in a predetermined direction, thereby causing the particles to collide against rotating drums. As a result of the collision, a portion of a quantity of water initially deposited on the particles is removed therefrom and transferred to the drums, which is thereafter separated from the drums by a centrifugal force created by rotation of the drums. A plurality of notches or slits may be formed to axially extend along the periphery of the drums so that the deposited water moving along the periphery will tend into contact with be separated therefrom when it comes to one of the notches or slits. An air jet stream passing through the respective slits to the outside will function to facilitate the water removal from the periphery of the drums.

Abstract: Filler is added to a particle form evaporator to facilitate the creation and maintenance of a polymer particle bed.

Abstract: The circulation of heat transfer fluid through the low temperature heat exchanger in the temperature control system of a freeze dryer is selectively increased when the temperature of heat being applied to the product shelf assembly in the freeze dryer exceeds the desired temperature. Preferably, a servo-controlled mixing valve selectively bypasses the low temperature heat exchanger so that the rate of cooling is very precisely adjusted without requiring the heat exchanger refrigeration unit to be cycled on and off. Since the refrigeration unit operates continuously, the reliability and operating lifetime of the refrigeration unit is increased. Moreover, the heat exchanger temperature is maintained at a minimum value. Preferably, the servo-control for the mixing valve includes a digitally controlled stepping motor and the adjustment of the mixing valve is sensed by a linear voltage displacement transducer. To prevent short cycling and oscillation, a dead band is introduced in the servo-control loop.

Abstract: A boot or shoe 10 has its upper lasted to an insole 12 made from leather or a permeable plastics material, and a sole unit 13 is bonded to the lasted upper and the insole. The sole unit is moulded from a resilient plastics material and is formed with a multiplicity of cavities 15 opening to its top surface underlying the insole and open topped channels extending between the cavities. Bulges 17 are formed on the bottom surface of the sole unit at the locations of the cavities. The act of walking causes the bulges to be compressed and to pump air along the channels to others of the cavities so as to disperse perspiration from the insole. The cavities preferably have a restricted cross-sectional area 18 where they communicate with the channels.

Abstract: An athletic shoe sole constructed to provide good cushioning and durability and to preclude overpronation of the foot. An outersole body progressively increases in thickness toward the inside edge of the sole from a longitudinal midline axis of thereof in a region extending from a heel portion to an arch portion of the outersole body, and is provided with a plurality of projection harder than the outersole body secured to its lower surface on an inner side of a heel portion of the outersole body and a plurality of projections softer than the outersole body secured to its lower surface on the remaining region of the outersole body. A cushioning midsole has a shape in section complementary to the thickness of the outersole body is overlaid on it.

Abstract: A device for fastening ski-boots, and which permits fine adjustment of the tightness of the fastening to be effected quickly and easily, includes a sprocket supported rotatably on a support plate and a tie with a rack portion engageable by the sprocket. The device also includes a ratchet mechanism for advancing the sprocket relative to the rack portion to tension the tie, and a ratchet mechanism for locking the sprocket so as to maintain the tension of the tie.

Abstract: A shoe with an ankle protector comprising a support panel along the lateral aspect or outwardly facing side of a shoe securely fastened to the shoe along the bottom edge of the support panel which extends from about mid-heel forwardly to the point on the shoe which is adjacent the distal joint of the wearer's fifth metatarsal, and an inelastic or non-stretchable strap extending from the rear edge of the support panel around the back of the shoe at an upwardly inclined angle, then forwardly across the upper part of the shoe along the medial aspect or inwardly facing side adjacent the medial malleolus of the tibia portion of the wearer's ankle, then around the front portion of the shoe and downwardly for connection of the strap to a forward portion of said support panel.

Abstract: In a pocket for footwear and designed to be the type to wraparound the upper front segment of the shoe, the wraparound pocket comprising a pair of liners, one being an inner liner, the other being an outer liner, approximately one end of the formed pocket securing with a proximate upper quarter portion of the shoe, while the other end of the wraparound pocket releasably secures with the upper segment of the other quarter portion of the shoe, one of the liners having a slot provided therein, and a closure in the category of a zipper providing for closing of the pocket slot during footwear usage.

Abstract: An improvement to a shoe primarily adapted for use in bicycling comprising a substantially non-elastic strap extending from a location proximate the upper heel of the shoe and extending substantially to the sole at a location proximate the ball of the foot to prevent stretching of the shoe from upward thrust during pedaling.

Abstract: An attachment for a front lift of a farm tractor comprises an elongated tool bar extending forward and supporting at its far end a large claw having three spaced downwardly curved, sharpened tines. The end of the tool bar nearest the lift is welded both directly and through braces to the front side of a rectangular hitch-and-tool-supporting frame, and drilled plates welded to the back side have properly spaced holes for coupling to the front lift.

Abstract: This invention relates to the protection of metallic surfaces susceptible to abrasion by rock-like material. According to the invention, a metallic surface susceptible to abrasion by rock-like material is protected by stud welding studs of abrasion resistant metallic material to the metallic surface in closely spaced relationship to cause the majority of the rock-like material to contact the abrasion resistant studs instead of the metallic surface. Typical of such metallic surfaces are a ground engaging tool, earth-working equipment, or chutes for conveying the rock-like material. The abrasion resistant metallic material comprising the stud can be formed of cast material of compacted metallic powder.

Abstract: A frame system including a plurality of elongated frame members joined end to end to enclose a display area and each having an inwardly projecting wall portion for bordering a perimeter of a display piece and a rearwardly projecting, inwardly opening channel having transverse lips spaced apart by an inwardly facing slot. Joining the ends of each pair of contiguous frame members is a unitary bracket having leg portions disposed at an angle corresponding to the angle between the contiguous members and retained by the channels therein. Each of the leg portions comprises a guide surface defining retainer cavity juxtaposed to one of the slots and retaining a locking cam for securing the frame sections.

Abstract: An intermediate frame for a sign box of the type having a first hinging member around its perimeter, and having an outer face frame for supporting a face panel, the intermediate frame having a generally rectangular construction with two ends, and a top and bottom joining at corners, each of them having an outer wall, a face panel support connected with the outer wall and extending inwardly, for supporting a face panel, a first hinging portion connected to the outer wall, and extending in a rearward direction for hinging interengagement with the first hinging member on the sign box, a second hinging member connected to the outer wall, and extending in a forward direction, to receive a second hinging portion carried on the outer face frame.Also included are a series of face frames for supporting a panel of flexible sign material, and panel tensioning members for use therewith. Such face frames may be hingedly mounted to a sign box, fixed to a vertical structure, and retrofitted to an existing sign box.

Abstract: In a firearm with a cylinder bolt mechanism, a locking chamber (27) is arranged in a space in the barrel between the rear end of the barrel and the rear end of the cartridge chamber for a bolt tip (28) on the bolt. Behind the locking chamber in the barrel is arranged a separate locking ring (23) between a stop (25) in the receiver and the rear end of the barrel. The locking ring is provided with lugs and grooves, and the bolt head is provided with corresponding claws which are able to pass through the grooves in the locking ring and to be rotated into the locked position ahead of the lugs in the ring. By introducing the bolt complete with the bolt head into the barrel and locking it securely in this position, it is possible to achieve greater accuracy because the bolt head acts as a stiffening connection between the barrel and the receiver, so that these components of the firearm are unable to move relative to each other as the result of oscillations in the barrel when the cartridge detonates.

Abstract: The invention relates to a catching hook having a straight portion (1) which in one end is provided with a hook (2) and another straight portion (3) which in the end opposite to the hook is provided with a handle (4). The portions are displaceable relative to one another between a catching position when they are extended at a maximum to a transportation position when they are pushed together. The hook (2) is rotatably connected to the end of the first straight portion (1), a locking device (6) being arranged in that end to prevent the rotation of the hook when used in its catching position, and after release permit rotation to a weighing position. The handle (4) is rotatably connected to a supporting device in the form of a sleeve (7) which is slidingly arranged on the corresponding straight portion, the handle being pivotably connected to the sleeve and after release from the end of the straight portion rotatable to a weighing position.

Abstract: A fishing appliance for use with a fishing pole and bait and interposed in the line connected therebetween. The appliance comprises a main stem having a stretchable spring secured at one end and a trigger arrangement attached at the other end for locking the spring in a stretched condition and releasing the spring in response to a force applied to said bait.

Abstract: A fishing line system is provided for attachment onto a fishing rod having a mounting member with front and rear carriers thereon. A plurality of line guide wheels are mounted in each of the front and rear carriers. Line from the conventional reel on the rod passes around the line guide wheels on its way to the tip of the rod. Inertial energy of the rotating guide wheels with the line tends to smooth out line velocity, and line stretch over the longer length of line tends to reduce peaks in line tension.

Abstract: Apparatus for carrying plants periodically to a watering station while ensuring that said plants are uniformly exposed to light. The apparatus includes at least one conveyor in the form of an endless cable disposed about a pair of spaced drums. One of the drums is driven by a motor to cause the cable to be circulated about the drums. The cable supports a plurality of plant hangers at spaced locations there along. Each hanger is arranged so that when a plant is suspended therefrom it is in a first orientation arranged to trip a sensor at the watering station to water the plant. The hanger is also arranged to automatically assume a second orientation when no plant is suspended therefrom. In the second orientation the hanger does not trip the sensor at the watering station. The cable is arranged to be driven at a slower speed during watering operations and at a higher speed during plant loading and unloading operations.

Abstract: A window regulator employing a flexible control cable as a transmission means, comprising a bracket secured to a window glass, an operating means and an inner cable connecting the bracket and the operating means through conduits, and both end portions of the inner cable being respectively wound up and off in the operating means to slidably move the bracket along a guide rail in order to perform an opening or closing action of the window glass, whereby a light, small and simple regulator is provided.

Abstract: A plastic and metal edge guard as fabricated by extruding plastic onto metal. The extrusion may take place onto a flat metal strip with the plastic and metal subsequently being formed into a desired cross sectional shape for the edge guard. Several embodiments are disclosed. In one embodiment the plastic is provided with a tapered shape so that when the plastic and metal are formed into the U-shaped cross section the plastic taper narrows toward the distal end of the legs to produce a feathering of the plastic. The plastic may cover either the entire surface of one side of the strip or selectively leave one or both marginal edges uncovered on the same side of the strip which can be formed into beads.

Abstract: A window construction is disclosed of the type having sashes slidable within a frame and maintained in alignment therein by means of guide strips adjacent the sashes which, due to their unique design, are capable of being removed from channels in the frame only when force is applied thereto from one side thereof to thereby ensure only removal of the sashes from one side of the frame.

Abstract: A jig grinder is provided with a controller for computing, as a function of an established radius and a preset feedrate, a rotational speed for rotating the machine spindle to provide a uniform surface speed at the cutting edge of the grinding tool as the tool alternates between linear grinding with an X and/or Y axis and arc grinding along the C-axis of the spindle. A method is provided for grinding straight surfaces and adjoining arcs at a constant feedrate without interruption.

Abstract: An adjustable tool mount positions a rotatable tool on a machine tool spindle by a central tool mount ring having a internal thread machined throughout. The thread engages a pin extending from the tool spindle, so that rotation of the assembly causes axial advancement of the tool mount. The tool mount is clamped and unclamped by a lock nut received on the tool mount which compresses a plurality of nested conical spring rings which are closely fitted to a counterbore within the tool mount and to the machine spindle. Compression of the spring rings tends to enlarge the ring outer diameter and tends to reduce the ring bore, thereby causing a secure frictional grip to be effected between the tool mount and machine spindle.

Abstract: An electrodeposited grinding tool having an electrodeposited abrasive layer formed by electrodepositing abrasive grains to an electrodeposition thickness at least three times as large as the diameter of the abrasive grains. Pores are dispersed in the electrodeposited abrasive layer in a volume ratio of 10 to 70%.

Abstract: This invention relates to a fixing device for fixing drills which are to be ground at their cutting edges. The fixing device comprises a baseplate, a stand carried by said baseplate, a pivot pin mounted on said stand near its top end, and a gripping device, which is slidably fitted on said pivot pin and adapted to grip the drill which is to be ground. The invention provides a simple and inexpensive fixing device of this type, which can be used for grinding twist drills or other drills, particularly by hobbyists, with adequate accuracy.

Abstract: The threaded portion of a tap drill is formed by mounting a tool blank for rotation about a longitudinal axis and mounting first and second grinding wheels integrally for rotation about a common second longitudinal axis parallel to the longitudinal axis of the tool blank. The tool blank and a first grinding wheel are rotated about the respective longitudinal axes thereof while moved longitudinally with respect thereto, thereby employing grinding ribs of the first grinding wheel to form threads in the blank. The second grinding wheel then is moved closer to the blank and a smooth peripheral surface of the second grinding wheel grinds away outer portions of the threads at an end portion of the tool blank, thus forming a tapered starting end of the tool.

Abstract: Cleaning apparatus employing an abrasive laden water jet including a tank for water and abrasive, an eductor in the tank to one inlet of which a water supply is connected and another inlet of which is open to the water abrasive mixture, a mechanism, which may be the eductor, to fluidize the abrasive in the water in the tank, a line from the outlet of the eductor to a working nozzle which is supplied with water and abrasive mixture by the action of the water supply in the eductor, and a high pressure water line adjacent the nozzle to increase the velocity of flow of the mixture from the nozzle.

Abstract: A roof is disclosed for a mobile home or the like. The roof comprises an existing roof having peripheral blocks disposed along the entire peripheral edge of the existing roof. Insulative material overlies the existing roof and is encompassed by the peripheral blocks. Marginal flashing of impervious material overlies the peripheral blocks and includes a first and a second limb. An upstanding portion is disposed adjacent the distal end of the first limb. Supplementary roof sheets of impervious material overlie the insulative material, the upstanding portion and the first limb and a lag screw or the like secures the first limb between the supplementary roof sheets and the peripheral blocks.

Abstract: A prefabricated balcony platform including attachment members to fasten the platform to the wall of a building, and apertures to secure a parapet to the platform. The balcony platform consists of a load-carrying beam frame of a corrosion-resistant metal, such as aluminium, a bottom slab of refractory material attached to the lower face of the beam frame and a top slab attached to the upper face of the beam frame and consisting of a material having heat-transfer properties, preferably aluminium. In the beam frame intermediate the two slabs is provided a layer of sound-proof, refractory material, such as mineral wool.

Abstract: A space frame construction with mutually dependent surfaces includes plural polyhedra having rigid panel members that need not be interconnected along abutting edges. The panel members of each of said polyhedra are further related to each other through duality. Interconnection between the polyhedra is achieved through bevel angle panel members, sloped web panel members, and wedge brace panel members. An optional chock may be further utilized for supplemental reinforcement.

Abstract: The specification discloses a pool wall assembly including first and second pool wall panels and a brace supporting the panels. Structure is included for securing the brace to only the first panel so that the first panel and brace may be aligned together prior to the securement of the second panel. Structure is also included for securing the second panel to at least one of the first panel and the brace. An anchor assembly secures the brace in position. The anchor assembly includes a stake which extends through and slidingly engages the brace and a wedge, telescopically received in the stake, which can be moved with respect to the stake into forcible engagement with the brace to maintain the brace in position. Each panel includes an integral bead extending from the lower portion of its face to define the line to which the pool side wall overlap extends. Also disclosed is a method of erecting a pool wall using the structure disclosed.

Abstract: A self flashing skylight for installation on the downwardly sloping roof is disclosed, in which a central portion is convexly curved and the side edges are provided with channels adjacent the convexly curved portion so that rain water impinging on the skylight will tend to be diverted into the channels which direct the water to the bottom of the skylight.

Abstract: A composite building panel and method of its construction wherein a preferably rectangular sheet is nailed to wooden strips extending around the sheet perimeter to define a form. A layer of portland cement and sand mortar is spread uniformly over the sheet within the form. A plurality of insulation blocks are applied directly to the wet mortar with uniform spacing between the respective blocks and between the blocks and the wooden strips. Mortar is then spread over the blocks, filling the voids left by such spacing and establishing a covering layer over the blocks. A second sheet is then nailed to the blocks and fasteners extend through the sheets and into the wet mortar grid throughout the panel. Upon hardening the panels are installed by the removal of one or more of the wooden strips so that the projecting margins of the sheets may be lapped with other construction elements to create a secure joint.

Abstract: A novel prefabricated tile panel consisting of a rectangular or square substrate board having side-long rectangular convex and concave portions arranged regularly by turns around the sides of the rectangular or square shape and a multiplicity of tiles arranged regularly and bonded onto the substrate board is provided. The concave portion and convex portion are of specified dimensions, respectively. The convex portions are protruded and the concave portions are set back from the tiles arranged and bonded in a rectangular or square shape. Thus, the prefabricated tile panels can be assembled without trouble by inserting the convex portions of one panel in the concave portions of other panel or panels for installation of the tile panels.

Abstract: A concrete expansion and contraction joint is provided comprising a hollow single piece longitudinal extruded member having a cross sectional configuration which resembles an arrow head with a relatively narrow upper stem portion.When the expansion joint is inserted into the fluid concrete aggregate, the V-shaped bottom of the arrow head structure moves aside any stones encountered in the concrete by the top of the arrow thereby facilitating installation. The top edges of the sides of the V-shape upon immersion in the concrete form locking anchors. Horizontal portions extending laterally on each side from the upper central stem portion of the joint to a point near the top of the V sides form flanges that provide channels which block downward water seepage at the joint.

Abstract: An improved ceiling panel for use in concealed suspension is disclosed which includes framing a panel body member on the sides and rear face thereof in a manner that the lower surface of the panel is determined by the metal framing members. These members are preferrably extruded aluminum and hence the accuracy thereof and hence the accuracy of the lower surface of the panel can be maintained in a closer tolerance range. In addition the framing members include an inwardly directed flange which preferrably is held by an adhesive within an appropriately located kerfed recess in the edge of the body member. This structure serves to stiffen the panel and reduce deflection thereby providing a ceiling system of substantially improved quality. Height variations in ceiling systems are easily recognized and the present disclosure teaches a system of high quality while providing a system which is easy to install and has the advantages of ready access to the area above the ceiling.