Patent Application
20210372177
The present invention relates to the material and method of use to produce light duty hinges that are co-molded with substrates of the door and frame, in a single cure step. This application describes potential applications for this product in the woodcraft industry where the laminating adhesive resins are typically room temperature cure resins. However this described hinge material and method could be used with other resin systems for various industries.
Description of Prior Art Hinges are traced back to early civilizations where the hinges that rotated the heavy wood doors used a pivot bearing hinge that comprised a hole in the stone floor and a wood pivot-pin. The metal strap hinges that replaced the pivot hinges have been used for centuries and are still used today, but are just one of the wide variety of hinges available.
However, the development of new types of hinges with special requirements for mortise machine cuts, and tight installation dimension tolerances can result in substantial material and installation costs.
Accordingly, it is the general purpose and object of the present invention to provide a composite hinge material that can be used to quickly produce low weight, low-profile hinges installed in a single cure. This inventive hinge material is an assembly of a woven 3.0 oz/square yard fabric of a high strength PET Dacron fiber, plied with a 3-4 mil paintable polymeric adhesive tape to one side of the dry fabric. This combination of plying the adhesive tape to the dry fabric provides stability to the loose weave fabric, producing a material that can readily be handled for the layup and molding steps to produce hinges that are molded and integrally bonded onto the wood substrates in a single step.
The above described plied reinforcement material will be coated with a laminating adhesive resin to produce a composite hinge laminate, and in the same cure step, bond the hinge laminate to the adjoining substrates for the hinge. The fiber orientation in the laminate is oriented at +/−45 degrees to the hinge line to obtain maximum shear strength and stiffness. The resultant installed hinges are lite-weight, durable, structural bonded assemblies. This composite-hinge material produces tight tolerance installed hinges. Butt-hinged joints would have a standard clearance of zero inches, and no mortise cutouts.
This Composite Hinge material for typical wood cabinet construction could be supplied in strips of long lengths of a specified width (1.5 inch) to be cut to coupon lengths required by the user. This would yield hinges with ¾ inch-wide leaves and required length. The profile height of these hinges installed will be 10 mils. The same material could produce ½ inch long butt-hinges or a 6 foot piano hinge.
The polymeric tape ply of the composite assembly becomes permanently bonded to the hinge as the resin cures, and will serve as a paintable protective layer to the hinge.
The adhesive laminating resins recommended for use for producing these hinges for wood structures are industry standard, PVA based resin systems, “Titebond II and III”. Limited further testing showed that the contact-adhesive “Pliobond”, also could work well.
This specification also describes the following shop-aid tools that can be used for processing the composite hinge material—
1.A. Roller Compacting Tool—A hand held roller tool described in Design Patent Application #29/742,144. The surface of the roller is a water-resistant rubber-cork material and is used as a tool to massage the installed hinge coupons to remove any trapped air, and consolidate laminate. The roller will use a low friction axle to provide a roller assembly that can roll across the uncured hinge layup without inducing slippage between the substrates and hinge coupon of the plied material. The installation process for these hinges closely contains the adhesive resin, so that there typically is no significant amount of resin bleeding out the hinge assembly. Resin that may contaminate the cork roller can be quickly removed with a damp towel. After the installation is complete, the roller can be placed in warm water to remove any uncured resin. Rinse and damp dry, and the roller is ready for re-use.
1.B. Resin Septum Roller Tool—This tool is basically same as the cork roller described in section 1.A above, except the roller for this tool will have a surface that uses the same screen material as described in section 2. This roller can used to distribute and/or smooth out resin applied to a substrate. Tool is quickly cleaned in warm water, and is reusable. It can also serve as a smooth roller to massage a completed hinge-coupon installation.
2. Resin Coating Template—A shop-aid tool is described that will enable the users to have a guide-tool for applying the laminating-adhesive resin onto the substrates for the hinge coupon. The template for this application will use a standard vinyl/fiberglass screen with a 0.50 inch tab-handle at one end. See
In use, the template will be laid onto the marked position for hinge that has a light coat of the wet adhesive resin applied. The viscous adhesive resin on the substrate will seal that first side of the template to the substrate, leaving the opposite side to have an open cellular face that will be brush-coated with additional resin. The filled template will hold the laminating-adhesive resin needed to mold the composite-hinge. After a 5 minute pause, the template will be pulled-up from the substrates, leaving a 4-5 mil thickness of the adhesive resin positioned for the application of the hinge coupon. As the hinge-coupon is applied to that surface, the adhesive forces of the adhesive resin will secure the coupon and infuse the reinforcement fiber to mold the hinge laminates and structurally bond the hinge elements to the abutted substrates.
3. Coupon Harness The purpose of Harness tool is to facilitate accurate positioning of the hinge-coupon that will be placed on the marked position on the substrates for installation of a Composite-Hinge. This is a DIY item that simply uses a short (˜2.5 inch) section of a craft-stick (or coffee-stick) crossed at middle with a 2.0 inch length of 1 inch wide masking tape. To pick up a hinge-coupon, the tool is placed on the poly-face of coupon and the masking tape is smoothed to the surface. The craft-stick of harness tool would be held with thumb and forefinger of one-hand to facilitate positioning the Coupon to the substrates. The Coupon-Hinge would then be smoothed down to the substrates with opposite hand.
4. Installed Hinge Cosmetics—Several observers expressed concerns about the visible mark-off of the thin square edge around our hinge specimens. We have demonstrated a version of a hinge coupon that extends the length of the polymeric face material ˜0.2 inch beyond edge of the fiber reinforcement of the hinge. This provides a smooth feather-edge that is practically unseen on a painted surface. We have added this option as a dependent claim. See claim 4.
Note: For bonding cycle, abutted substrates can be held together by masking tape.
Installation—Method
