Abstract: An artist canvas frame comprises the usual rectangular frame members attached at four corners and having a canvas stretched around the periphery and held in place by staples or some other suitable means. To improve the stability of the frame a brace is provided substantially midway transversely across the back of the frame in one or both directions and is held in place by movable plastic socket members on each respective end of the brace and each socket member comprises a small rectangular tube having opposed side members extending therefrom fitted over the inside faces of opposed frame members, known individually as stretcher strips or stretcher bars.

Abstract: A forced air heating and/or cooling system in a building is provided with the usual main supply conduits or duct which have various branch ducts leading to different areas of the building. Pressure sensitive instruments at spaced locations in the main supply duct are connected by electrical wiring or pneumatic tubing to a comparing instrument which senses pressure signals from the different zones determining the maximum required pressure that must be supplied to the system. Zone thermostats sense increases in room temperature and operate conventional variable volume boxes to increase the supply of air thereby lowering the air pressure. The comparing instrument sends a signal to a variable speed drive comprising a motor having a spring loaded pulley connected by a drive belt to a fan pulley and the motor is electrically driven by a separate drive means to adjust the tension on the spring loaded pulley thereby changing the speed of the fan for a more economical operation.

Abstract: An articulating grader comprises a rear driver section which has an engine and hydraulic pump arrangement for driving a pair of wheels on each side. A chassis frame includes lower frame members for supporting a mold board assembly which is controlled and set in angularity and vertical movement but supported from a frame support member on the top by a hydraulic piston and cylinder and guide member arrangement, whereby after adjustment the mold board may be moved upwardly vertically and again moved back down to original position without disturbing the setting. A front articulating frame supports steerable wheels controlled by hydraulic power steering.

Abstract: An electrically operated shop towel vending machine for dispensing a clean shop towel only in response to the proper input of the satisfactory dirty shop towel which is inspected as to length, strength, texture and/or bulk. The input section comprises an inspection mechanism which employs a continuous chain on which a towel is hooked passing beneath an inspection wheel which operates a sprocket and measuring chain only in response to proper actuation of the wheel to activate electrical switches indicating that a proper towel has been inserted. The delivery section of the machine comprises a continuously moving pickup conveyor which delivers the towel from a pile of towels to a transfer roll which employs an arrangement of card cloth patches with the needles projecting in predetermined directions in cooperation with a transfer belt and a discharge roll to separate and shed more than one towel so that only one towel is discharged from the cabinet past an electric eye or photocell to stop the machine.

Abstract: The present method may be employed to reduce the temperature of water including chilling or freezing the water to produce ice and slush and simultaneously therewith keeping the water in motion, as from one container to another, without the use of a circulating pump. Liquid carbon dioxide is used as an expendable refrigerant by releasing same continuously beneath the water and then the activity of the conversion of the carbon dioxide changing from a liquid to a solid and gas is applied in a confined space to circulate the water as a liquid heat exchange medium.The basic apparatus comprises a large container of water in which are one or more conduits or stacks at the bottom of which are holes admitting the water to be chilled. A CO.sub.2 nozzle receives liquid CO.sub.2 and a pressurized supply tank discharges the CO.sub.2 as a solid and gas through the nozzle which receives the CO.sub.

Abstract: A dispenser outlet which may be located in the cab of a truck is mounted on a cup support which includes a small drain to which is attached a drain hose leading to the outside. An insulated container, such as a thermos or other insulated container, is located in a remote point such as the back compartment in the tractor or in the trunk of an automobile, and is connected to the dispenser outlet by means of a small plastic hose. A small electrical pump mounted in the bottom on the container is connected to the outlet hose and is operated from the vehicle electrical supply.

Abstract: A single shot rifle comprises the usual elongated barrel of any desired calibre with the shell receiving end screwed into a receiver having spaced sides defining a passage for a cartridge to be inserted and removed therefrom. A falling breechblock is provided with a stock extension for insertion in and permanent mounting on a stock so that the breechblock and stock move together. The trigger mechanism, hammer and extractor mechanisms may be of any suitable and conventional construction including the usual cocking lever which actuates the spring biased hammer that is released by a trigger.

Abstract: A molded plastic fastener of the sort which may be used as part of steps for a concrete manhole has molded plastic, circular threads or projections which are tapered and deformable so that when inserted in a drilled hole of slightly smaller diameter the projections will be deformed and bend under pressure to retain the fastener in place.

Abstract: A dust mitt comprising a dust mitt cover made of a nappy or pile material into a pocket formation by folding the material inwardly along the sides to form edges and then folding the material upon itself to form the pocket with an open end into which is inserted a folded section of soft, resilient and absorbent foam plastic material of sufficient bulk and thickness to fill the inside of the pocket. The open end of the pocket is closed into a small fabric mouth which optionally receives one end of a stick handle inserted inside the folded foam material.

Abstract: Especially effective for use with fast hardening metal fillers comprising resin and catalyst the present spreader, which may be integrally molded in a continuous combination of injection and blow molding comprises an elongated handle which is hollow and deformable and a blade which is solid whereby sculpturing and contouring may be achieved more readily through hand manipulation and the spreader is more easily cleaned.

Abstract: A finger actuator is provided for attachment on a conventional knife blade of the sort which is folded into the handle when not in use. The actuator comprises a resilient tool steel saddle arrangement fitted very tightly over the knife blade. A first plate extends upwardly from said saddle in a direction away from the edge of the knife blade and then extends outwardly in a direction substantially transverse to the longitudinal axis of the knife blade to provide a flat plate area against which the thumb pushes to open the blade while the other fingers of the hand hold the handle in the palm.

Abstract: The present method may be employed to reduce the temperature of water including chilling or freezing the water to produce ice and slush and simultaneously therewith keeping the water in motion, as from one container to another, without the use of a circulating pump. Liquid carbon dioxide is used as an expendable refrigerant by releasing same continuously beneath the water and then the activity of the conversion of the carbon dioxide changing from a liquid to a solid and gas is applied in a confined space to circulate the water as a liquid heat exchange medium.The basic apparatus comprises a large container of water in which are one or more conduits or stacks at the bottom of which are holes admitting the water to be chilled. A CO.sub.2 nozzle receives liquid CO.sub.2 and a pressurized supply tank discharges the CO.sub.2 as a solid and gas through the nozzle which receives the CO.sub.

Abstract: A method of processing oil shale to recover liquid or gaseous products which comprises constructing longitudinally sloping trenches excavated in a mineral deposit which is relatively impermeable in relation to the crushed oil shale, placing the crushed shale into the sloping trenches and covering same with a compacted layer of clay or other relatively impermeable and essentially inorganic minerals and thereafter igniting the oil shale at the upper end of the trench. Air is introduced at points along the upper end of the trenches and as the retorting zone moves longitudinally downward in the sloping trenches the liquid and gaseous materials are withdrawn at points located at the lower end of the trenches.

Abstract: Concrete pipe is molded between concentric steel cylindrical shells in which there are openings on each side receiving plastic inserts defining respective keyed cavities that remain in the molded concrete pipe after curing and removal of the concentric steel shells so that large keyed eye-bolts may be inserted in the respective keyed inserts. The initial positioning of the plastic mold keyed insert is accomplished by means of a keyed plastic plunger mounted on an attaching plate which includes notches on each side to fit over attaching screws on each side of the outside steel shell. The plunger has a keyed end. The hollow plastic insert with a soft gasket around the top has a keyed plunger inserted under pressure therein for removal therefrom and replacement by the eye-bolt after the curing of the pipe is completed.

Abstract: The method may be employed for the mixture of certain types of products which require two or more component chemicals or compounds that must be mixed together immediately prior to use. The method comprises mixing the two compounds in the usual fashion inside of a mixing chamber by continuously supplying each of the compounds to the mixing chamber and then introducing air into the chamber while maintaining the chamber open at one end for the dispensing of the material whereby the air provides agitation for the mixture of the materials and provides a suction forwardly of the mixing chamber to draw the mixed compounds therefrom.The apparatus is in the form of a mixing and dispensing gun which comprises a frame on which there is a previously known arrangement for introducing and supplying two or more chemical components to a mixing chamber thru a mixing block with which is mounted an air control valve system for controlling the entry of the two components.

Abstract: The present dental articulator provides a means for correcting most incorrect bites after the models have been mounted and permits the model to be removed and placed on another similar articulator in the same position. An articulator frame comprises a base having opposed side frame members but supports a pivoting frame attached thereto by pivot pin and coil spring arrangement. A bottom bracket removably mounted on the base supports a U-shaped model bar for the lower model with adjustment means thereon removably supporting the model frame. An upper bracket on the pivoting frame removably supports a U-shaped upper model bar for adjustment thereon. The upper and lower models are mounted and adjusted in fixed position and then may be removed and sent without the articulator to be remounted later in a similar articulator.

Abstract: A release device for drawing the bow string which is released to propel an arrow having an arrangement of first and second pivoted jaw members each having a jaw thereon mounted by means of a pivot pin to a handle. A pivoted trigger member on the handle has a notch therein into which fits a projecting portion on the first jaw member for engagement when the jaws are closed. The jaws are clamped over the bow string and the trigger is pulled to disengage the projecting portion and release the bow string and arrow.

Abstract: A plurality of individual pot stands which have support rings of substantially identical size and construction but each having three legs of different lengths than the legs on the other stands. The stands may be nested and stacked together by placing the rings on top of each other and supporting the whole assembly on the stand with the longest legs. Individually the stands may be used to support pots and the like as a double-boiler, for cooling a pot or for warming the pot from a flame beneath like a chafing dish.