Plastic fasteners

Abstract: A one piece integrally molded plastics deck anchor comprises a base flange 454 with a channel 458 in it, an expansible toggle locking mechanism 456 attached to the base flange, and a tube 452 extending from the flange, to receive a fixing bolt or stud.

Description: BACKGROUND OF THE INVENTION 1. Technical Field This invention generally relates to plastic fasteners, and more particularly to plastic fasteners of the type having expandable locking means for securely maintaining the fasteners in place within an opening. 2. Background Art Plastic fastening devices having expandable locking means are well known. For example, several fastening devices of this type are described in detail in United States Patent 3,651,734. While these devices work very well in a wide range of applications there is room for improvement of them in several important respects. For example, one type of such fastening device includes a hook portion, and a plurality of these devices are commonly secured to a wall to hold a rack, such as a tool rack or a merchandise display rack, up against that wall. These particular fastening devices are normally locked within a wall opening by means of a screw that is inserted through a screw opening in the device and that engages a toggle lock thereof to hold that lock in an overcenter position. The hook portions of these fasteners are spaced an appreciable distance from the specific portions of the devices that form those screw openings, so that, in use, the screws inserted through the screw openings do not directly support the hook portions of the fasteners or any weight mounted thereon. This problem would also exist when these fastening devices are secured to ceilings, and a similar problem is encountered when other types of fastening devices are attached to floors or decks and used as supports for other structural members. Another fastener using expandable locking arms is disclosed in US-A-3213746, however this mechanism uses expandable arms which do not lie flat when expanded and provide only limited retaining strength. US-A-4174910 discloses a paper anchor comprising expandable toggle arms, and a flat retaining member, which may be separate, the paper being trapped between the expanded arms and the retaining member. An object of the present invention is to provide a new type of plastics anchor capable of being used as a deck anchor for structural elements. According to the present invention, there is provided a one piece integrally moulded plastics anchor comprising: a. a base member having a flange; b. and expansible locking means connected to the base member and having a collapsed position for insertion through an opening defined by a structural member, and an overcentre expanded position to lock the anchor within the said opening in a position defined by the flange; c. the base member and flange having an opening for insertion of a member into operative engagement with the locking means; characterised in that the anchor is a deck anchor, and an elongate hollow extension is connected to the flange and extends away from it on the side opposite the locking means, the said extension (452) and base member defining an open pathway which in use receives an elongate structural element which in use remains located within the elongate extension while pushing the locking means into its expanded position or holding the locking means in the expanded position. Preferably, the elongated extension is a cylindrical or square tube, and it is intended to support a structural element such as a threaded rod or bar. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1 and 2 are side views of a deck anchor in accordance with the present invention. Figures 3 and 4 are front and rear views of the deck anchor. Figures 1 to 4 show an integral injection - moulded plastics deck anchor 450 generally comprising a base member 451 having an annular flange 454 with a central opening and a reinforcing channel 458 and expansible locking means 456. A hollow tube 452 is integrally molded to flange 454 on the side opposite the expansible locking means 456. The entire anchor is made by an injection molding process, using suitable plastics material as described in EP-A-0198902. Expansible locking means 456 includes first and second toggle arms 122 and 124, pivotal connecting joint 126, and first and second flexible connecting arms 130 and 132. The various parts are formed together from a resilient plastic in an injection molding process. Suitable materials for the construction of the anchor include polypropylene, polyethylene, and nylon, as well as a wide variety of materials which may be chosen with consideration to the fastener configuration, the manner of formation, and the intended use. Expansible locking means 456 is integrally connected to base member 451. More specifically, flexible connectors 130 and 132 are joined to flange 454 of base member 451 and extend downward and outward therefrom. Lateral ends of toggle arms 122 and 124 are integrally connected to the bottom outward ends of connector arms 130 and 132. Toggle arms 122 and 124 transversely extend across the bottom of the anchor, and centrally located end portions of the toggle members are joined together by integral pivotal connection 126. Pivotal connection 126 has a reduced thickness in comparison to the thickness of toggle arms 122 and 124, and the pivotal connection forms a centrally located opening 460. Flexible connectors 130 and 132 are laterally spaced apart to define a central open area into which the pivotal connection 126 and centrally located end portions of toggle arms 122 and 124 move upon collapse of the locking structure. To lock the anchor within an opening, toggle arms 122 and 124 are pushed into their collapsed position, between connecting arms 130 and 132, and then the toggle arms are inserted through the opening. Once inserted through the opening, connecting members 130 and 132 flex outward due to their inherent resiliency, tending to pull toggle members 122 and 124 into their expanded over-center position. If connecting members 130 and 132 do not pull toggle members 122 and 124 completely into their overcenter position, the toggle members may be pushed into that position--and, in any case, the toggle members may be locked in the expanded position--by inserting a member through the tube 452, and the central opening in the flange and using it to push the toggle members outward. In use, the expansible locking means 456 are collapsed and inserted into a hole in a steel plate or decking. Then, a metal stud, J-bolt, or eye bolt, or similar mechanical anchoring member (not shown) is inserted into tube 452 so as to fit snugly within the tube with one end of the member, suitably bearing external screw threads, projecting out from the expansible locking means 456 through the opening 460, and the other end having a head, or J or eye, projecting out from the end of the tube 452. As a result, the member will be held in an upright position and will cause the expansible locking means 456 to expand to its locked position, if not already in that position. Then, concrete or cement (or even adhesive) can be poured around the tube portion 452 of the anchor 450 to mechanically interlock with the exposed head or J or eye of the anchoring member and secure the anchor in its vertical position. The exposed screw threaded opposite end of the anchoring member below the concrete filled decking may then be used to support pipe fittings or hangers, suspended ceiling hangers, and similar structural parts. In addition to providing additional mechanical strength to the plastic anchor, channel 458 allows some of the poured cement or concrete to flow between it and the decking for additional strength and stability.

Claims: A one piece integrally moulded plastics anchor comprising: a. a base member (451) having a flange (454); b. and expansible locking means (456) connected to the base member and having a collapsed position for insertion through an opening defined by a structural member, and an overcentre expanded position to lock the anchor within the said opening in a position defined by the flange (454); c. the base member and flange having an opening for insertion of a member into operative engagement with the locking means (456); characterised in that the anchor is a deck anchor, and an elongate hollow extension (452) is connected to the flange and extends away from it on the side opposite the locking means, the said extension (452) and base member defining an open pathway which in use receives an elongate structural element which in use remains located within the elongate extension while pushing the locking means into its expanded position or holding the locking means in the expanded position. A deck anchor according to claim 1 in which the locking means (456) are provided with an opening (460) through which the structural element extends. A deck anchor according to claim 1 or 2 in which the elongate extension is a tube. The deck anchor according to claim 3 in which the tube is cylindrical. The anchor according to claim 4 wherein said structural element is a threaded rod or bar. An anchor according to any of claims 1 to 5 in which said locking means comprises a toggle assembly having i) a pair of adjacent toggle arms, and ii) means connecting adjacent ends of said toggle arms together for relative pivotal movement between collapsed and expanded positions. The anchor according to any of claims 1 to 5 wherein said expansible locking means comprises: a pair of connecting arms extending rearwards and outwards away from said base member and integrally connected therewith; a pair of toggle arms connected to lateral ends of said connecting arms and extending inwardly therefrom; and means connecting inward ends of said toggle arms together for pivotal movement between collapsed and expanded positions. The anchor according to any of claims 1 to 7 in which the flange has a reinforcing channel (458),

Inventors: GARFIELD NATHANIEL H, MCSHERRY THOMAS W, GARFIELD, NATHANIEL H., MCSHERRY, THOMAS W.
Applicants: MECHANICAL PLASTICS CORP, MECHANICAL PLASTICS CORP.
Application year: 1985
Main classification: F16B13
IPC codes: F16L3, F16B13