Abstract: A fire retarding heating and cooling duct to impede the progress of fires in buildings and houses. The fire retarding duct is comprised of a duct core covered with a heat meltable plastic material that will melt at temperatures in the range of 180.degree. F. and above. The duct core is preferably constructed in short sections of about six feet for connection between heating and cooling, and building inlet and outlet plenums. The heat meltable plastic duct covering melts almost immediately when a building fire enters a plenum preventing the spread of a fire throughout the duct system.

Abstract: A completely sealed knock-down collar for joining heating and cooling ducts to plenums. The knock-down collar is formed from an elongate sheet metal strip punched with a plurality of tabs along one edge, a plurality of diagonal slits spaced from the tabs, a target on one end and a slot on the other. The sheet metal strip is rolled into a tubular shape with diagonal slits forming a herringbone mounting flange and the tongue fitting the slot to lock the strip in the tubular shape. A non-drying sealer is provided beneath the herringbone mounting flange and along one end to seal the collar when mounted in a plenum.

Abstract: Strengthening the core of an insulated flexible duct formed of a helical wire wrapped with a flexible material with reinforcing tape. Strengthening tape is applied to the surface of the duct along its entire length. The apparatus for applying the strengthening tape is a tray having adjustable wiping arms. The wiping arms stretch the duct out as it is pulled through the tray. A roll of tape is mounted adjacent to the wiper arms and is automatically applied as the duct is pulled along the tray through the wiper arms. At least two wiper arms and continuous strips of tape along the longitudinal surface of the duct core are preferred.

Abstract: An adjustable head rest for chaise lounges that allows a person to lie on their stomach without the necessity of turning their head. The head rest is constructed of a frame that fits between the slats of an existing chaise lounge and is adjustable by moving the portion beneath the slats in toward or away from the lounge. The extended end of the frame has a head support in the form of a strap attached across the frame. The head support is mounted on an angle portion of the frame that provides a comfortable position to rest the forehead. In a preferred embodiment of the invention the frame is in a U-shaped construction with the head support being slidable from an open end of the U-shape frame to the closed end to allow the adjustable head rest to be reversible for use with most types of chaise lounges. The U-shaped frame preferably has hinges and telescoping arms to allow the head rest to collapse to a small package for ease of transporting.

Abstract: An air return filter or air supply grille assembly having an interchangeable perforated face plate hingedly attached directly to a molded fiberglass plenum. The molded fiberglass plenum has a preformed recess for receiving and positioning a filter resting on the face plate when used as an air return filter grille assembly. The hinge system for the interchangeable perforated face plate is comprised of a pair of mating half hinges with one half secured to the plenum and the other half secured to each interchangeable face plate. The grille assembly can be mounted and a perforated face plate selected to provide an air return filter grille assembly or an air diffusing supply grille assembly. The air filter grille assembly is constructed to mount easily on T-bar suspended ceilings with the perforated face plate held closed by manually rotatable pawls.

Abstract: An air return filter grille assembly having a perforated faceplate hingedly attached to a molded fiberglass plenum. The molded fiberglass plenum has a performed recess for reclining and positioning a filter resting on the faceplate. An abutment and leaf spring on the faceplate hold the filter firmly in the recess. The air filter grille assembly is constructed to mount easily on T-bar suspended ceilings with the perforated faceplate held closed by manually rotatable pawls. Another reason for the spring is to keep the filter in position as the unit cycles on and off, thus preventing the accumulated dust and dirt on the filter from staking down or dusting back into the room.

Abstract: A rigid, molded fiberglass duct having an integral bendable elbow comprised of two sections of cured fiberglass securely bonded to a corrugated metal-foil sleeve. The method of manufacturing the rigid bendable duct is by sliding a corrugated metal-foil sleeve on to a mandrel and then wrapping the ends of the sleeve with uncured fiberglass. The area of the uncured fiberglass overlapping the corrugated, bendable sleeve is compacted by means of a collar which fits around the sleeve and the fiberglass and compresses the fiberglass into the corrugations of the sleeve. In order to enhance the bond, protusions may be provided in the overlapping area of the sleeve, such as by cutting the corrugated sleeve and bending it up to form tabs.

Abstract: A method and apparatus for strengthening the core of an insulated flexible duct formed of a helical wire wrapped with a flexible material. Strengthening tape is applied to the surface of the duct along its entire length. The apparatus for applying the strengthening tape is a tray having adjustable wiping arms. The wiping arms stretch the duct out as it is pulled through the tray, testing bonds securing the material around a reinforcing coil of wire. A roll of tape is mounted adjacent to the wiper arms and is automatically applied as the duct is pulled along the tray through the wiper arms. At least two wiper arms and continuous strips of tape along the longitudinal surface of the duct core are preferred.

Abstract: A rigid, molded fiberglass duct having an integral bendable elbow comprised of two sections of cured fiberglass securely bonded to a corrugated metal-foil sleeve. The method of manufacturing the rigid bendable duct is by sliding a corrugated metal-foil sleeve on to a mandrel and then wrapping the ends of the sleeve with uncured fiberglass. The area of the uncured fiberglass overlapping the corrugated, bendable sleeve is compacted by means of a collar which fits around the sleeve and the fiberglass and compresses the fiberglass into the corrugations of the sleeve. In order to enhance the bond, protusions may be provided in the overlapping area of the sleeve, such as by cutting the corrugated sleeve and bending it up to form tabs.

Abstract: A universal air diffuser comprised of a fiberglass plenum having an open side and means for attaching a duct connector on a closed side opposite the open side. The closed side of the fiberglass plenum is covered with a close-fitting non-porous material which reinforces the fiberglass to allow cutting holes for attachment of air ducts. A plurality of shallow grooves on the exterior of the closed surface provide cutting lines for hole patterns to cut holes for various standard size ducts. The reinforcing material is a fiberglass-reinforced foil which maintains the integrity of the hole cut in the surface and provides a non-porous surface for adhering to duct tape.