Abstract: An encapsulated luminescent particle for use in an aqueous environment includes a luminescent pigment capable of being illuminated by an external light source and an encapsulating material, wherein the encapsulated luminescent particles are between about 1.5 mm and about 5 mm in size. The encapsulating material permits luminescence from the luminescent pigment upon excitation by an external light source, such as, a blacklight, while allowing the luminescent pigment to be safely used in an aqueous environment, such as a pool, spa, or the like.

Abstract: A method of manufacturing a luminescent tile for use in an aqueous environment includes admixing a luminescent pigment capable of being illuminated by an external light source, a forming material, and a catalyst to create a luminescent mixture. Casting the luminescent mixture into a mold and allowing said mixture to substantially harden thereby creating a luminescent tile. The forming material permits luminescence from the luminescent pigment upon excitation by an external light source, such as, a blacklight, while allowing the luminescent pigment to be safely used in an aqueous environment, such as a pool, spa, or the like.

Abstract: A method of manufacturing a luminescent tile for use in an aqueous environment includes admixing a luminescent pigment capable of being illuminated by an external light source, a forming material, and a catalyst to create a luminescent mixture. Casting the luminescent mixture into a mold and allowing said mixture to substantially harden thereby creating a luminescent tile. The forming material permits luminescence from the luminescent pigment upon excitation by an external light source, such as, a blacklight, while allowing the luminescent pigment to be safely used in an aqueous environment, such as a pool, spa, or the like.

Abstract: An encapsulated photoluminescent particle. The photoluminescent particle may be used in the formation of aggregates. The aggregates may be used in the formation of various substrates, especially for aqueous environments, such as swimming pools, aquariums, spas and fish ponds. In general, the photoluminescent particles include a resin, a photoluminescent compound, and a catalyst. The composition may be granulated to form the photoluminescent particle. The photoluminescent particles may be formed without the need of additional filler materials.

Abstract: A safe door lock with a servo motor operated cam is described. A retracting lever is pivotally secured to the locking bolt and is displaced on a pivot connection with the bolt by the cam. The position of the cam and the bolt are detected by microswitches. When the retracting lever is in a locking position, the bolt cannot be retracted within the lock housing. The cam is operated by a servo motor and locked in position by the gear train which includes a worm gear. The locking bolt may be a slam bolt having a spring biased latch which slides therewith or the locking bolt may be a deadbolt when the lock is used with a boltwork system of a vault door.

Abstract: A combination door lock having a self-canceling combination mechanism which is secured inside the lock housing and is provided with spring-biased hook engaging fingers which engage one or more of the combination discs when these discs are aligned at a predetermined position where a retracting cam engages a bolt-retracting lever. Once the bolt is retracted by the lever these hook fingers engage with an associated combination disc and move it out of its predetermined position to a random position thereby scrambling or self-canceling the combination or the placement of the discs. Accordingly, it is not possible to predict the precise position of the combination discs after the bolt has been retracted and the door opened.

Abstract: The tensile strength and core hardness of a sand mold or core is increased by incorporating into a mixture of a thermosetting acid-hardenable resin and sand, a dialkyl ester of the formula:R.sub.1 OOC(CH.sub.2).sub.n COOR.sub.2wherein R.sub.1 and R.sub.2, which may be the same or different, are selected from alkyl of 1 to 20 carbon atoms and n is 2, 3 or 4. The ester may be added directly to the resin or sand, or in conjunction with the acid catalyst. Ferric chloride together with the dialkyl ester provides a sulfur-free catalyst for polymerization of the resin.

Abstract: Sand molds or cores are prepared by coating sand particles with an acid-curing condensation type resin consisting of poly furfuryl alcohol or admixtures of poly furfuryl alcohol with other acid-curing resins. The resin composition is formed into a desired shape and is cured at ambient temperature over a period of between a few seconds and a few minutes by means of an acid produced by in situ oxidation of sulfur dioxide. Sulfur dioxide is introduced into the molding composition together with an oxidizing agent which effects oxidation of the sulfur dioxide within the mold or core composition. Preferably, the oxidizing agent is an organic peroxide incorporated on the sand or introduced with the resin composition.

Abstract: A method of making sand molds, cores or the like for use in casting foundry pieces. First and second continuous conveyors are utilized, the first conveyor having a number of pattern pieces and flasks attached to it, and the second conveyor for transporting the sand molds, cores or the like from the flasks after deposition thereon by inverting the flasks over the second conveyor. Each flask is filled in turn with sand and binder mixture when in an upright position, the sand-binder mixture is compacted and partial curing thereof is allowed, the flasks are inverted in turn to bring the sand mold into contact with the second conveyor, and the sand mold is released from each flask while it is inverted. Each flask is then brought back into an upright position for receipt of further sand-binder mixture to repeat the process, the process being substantially continuous.

Abstract: An automatic mold and core forming machine is described wherein an endless chain conveyor is in engagement with a plurality of flasks carriers for movement therewith with a mold material retaining means positioned adjacent and end of the chain conveyor and arranged to contact the material in the flasks and retain it therein as the flasks are inverted in passage around the conveyor. A flask filling and compacting assembly is provided adjacent the opposite upper end of the chain conveyor for automatically filling and compacting the flasks as they pass thereunder and a mold draw station is provided at the underside of the chain conveyor.