Plastic Hinge

Abstract

This invention relates to a plastic hinge provided with the holes for fixing on the right and left fixed plates at the places asymmetrical to each other respectively, whereby making it possible to firmly fix the hinge again by means of using the right and left fixed plates conversely to each other in case of strain being caused.

Description

This invention relates to the construction of tough plastic hinge.

The object of this invention is to provide the hinge far excellent in strength, lower in price, light in weight and free in coloring as compared with metallic hinges by means of making use of plastics as the material.

Almost all of the conventional hinges are made of metal. All of these metallic hinges have such defects as being high in price, heavy in weight and less beauty in coloring, while steel hinges might gather rust in case of having been used for a long time. There are various kinds of plastic hinges, about which studies have recently been made with a view to improving the unfavorable points referred to above. Almost all of these plastic hinges, however, are inferior in terms of strength to the conventional metallic hinges.

The present invention consists of a certain novel features making a plastic hinge superior to metallic hinges.

In the accompanying drawing;

FIG. 1 is a plan view showing the state in which the hinge covered by the present invention is opened.

FIG. 2 is a perspect view of the hinge according to the present invention.

FIG. 3 is a sectional view on the line III--III of FIG. 1.

For a better understanding of the present invention, reference is made to the accompanying drawing showing a plastic hinge provided with the thick convex portions; for examples 9 and 10, at each center of which the holes for fixing 14 and 15 are drilled, on one of the fixed plates corresponding to the knuckles 2 and 4 of the other fixed plates; and with the concave portions 9' and 10', into which the convex portions 9, 10 are fitted at the places on the other of the fixed plates corresponding to the said convex portions. In the drawing, 6, 7, and 8 are the convex portions provided at the places opposing respectively to the knuckles 1, 3 and 5; 11, 12 and 13 are the holes for fixing drilled at each center of convex portions 6, 7 and 8; and 6', 7' and 8' are the concave portions, into which the convex portions 6, 7 and 8 are fitted. The arrow marks A, B, C, D, E in FIG. 1 show the direction of each force applied on a plastic hinge when it is fixed to a door and a frame pole adjacent to the door. When a plastic hinge is fixed to a door and a frame pole, a resultant force of B, D and E is applied on the upper plate in FIG. 1, while a resultant force of A and C is applied on the lower plate as the force corresponding, in parallel, to the resultant force of B, D and E. These forces are all applied on the places opposite to the knuckles of one of the fixed plates. Consequently, the present invention has thick portions, i.e., convex portions, on which forces are applied most, with the holes for fixing being provided on each center. The places on the other of the fixed plates corresponding to the convex portions form the concave portions, into which the said convex portions are fitted.

As mentioned above, the present invention has the holes for fixing, which are drilled at the places most effective, and moreover being thick convex portions, on which the holes for fixing are drilled, are far thick in thickness as compared with the corresponding portions of metallic hinge, whereby making it possible to completely prevent the damage by the pressure of screws.

Conventionally, the hinge is fixed to a door and a frame pole with screws passing through the holes for fixing. With the lapse of long time after fixing the hinge to a door and a frame pole, the wood portion rotted or the screw holes came to too large resulting in giving rise to strain to the portions, where the hinge is fixed, in many cases.

However, the hinge of the present invention is provided with the holes for fixing on the right and left fixed plates at the places asymmetrical each other respectively. In case of strain being caused, it is possible to fix again the hinge firmly by means of using the right and left fixed plates conversely each other.

Polycarbonate resin, ABS resin, Polyacetal resin, etc. are strong in strength and tenacity as the resins to be used for the manufacture of this hinge. These resins are most suitable as the raw materials for plastic hinges. It stands to reason that the special characteristics of risins, such as low-price, toughness and light weight, are made the best use of in such plastic hinges. And further, as a matter of course, such plastic hinges are superior in terms of color to the conventional metallic hinges.

The result of pressure test on the hinge covered by the present invention shows the strength of 850 kgs about three times as strong as the brass hinge which is 300 kgs in pressure resisting strength, while the result of tension test shows the strength of 190 kgs about two times as strong as the brass hinge which is 100 kgs in tensile strength.

Claims

What is claimed is:

1. A hinge composed of a rigid non-metallic material comprising

a. a pair of hinge plates, each plate including a generally flat surface and a plurality of knuckles spaced along one edge thereof, said knuckles being spaced such that with said one edge of each of the pair of plates arranged adjacent each other the knuckles on one plate mesh with and alternate with the knuckles on the other plate, each knuckle including an opening therein positioned such that the openings are in alignment, and

b. a pintle passing through said opening such that one plate may be pivoted with respect to the other,

c. the flat surface of each of said plates including a plurality of embossments and a plurality of recesses, each embossment being located on a portion of said surface extending between the parts of said one edge not having said knuckles and the opposite edge thereof to strengthen said plate at the points of greatest strain during use, and each recess being located in a portion of said surface extending between the parts of said one edge having knuckles and the opposite edge thereof where said plate receives less strain during use, the size and arrangement of said recesses on each plate complementing the corresponding embossments on the other plate,

d. whereby portions of each of said plates in alignment with each of said knuckles are thinner than corresponding portions of each of said plates in alignment with the edge between said knuckles, and when said plates are pivoted such that said surfaces of the plates are in contiguous relationship the embossments of each of said plates will be received in the recesses of the other plate and the overall thickness of said hinge will not be substantially greater than the combined thicknesses of the two plates.

2. A hinge as defined in claim 2 wherein the embossments of said plates include holes for receiving screws for mounting said hinge.

3. A hinge composed of a rigid, non-metallic material comprising

a. a pair of hinge plates, each plate including a generally flat surface and a plurality of knuckles spaced along one edge thereof, said knuckles being spaced such that with said one edge of each of the pair of plates arranged adjacent each other the knuckles on one plate mesh with and alternate with the knuckles on the other plate, each knuckle including an opening therein positioned such that the openings are in alignment,

b. a hinge pin, said pin passing through said openings such that one plate may be pivoted with respect to the other,

c. the flat surfaces of each of said plates including a plurality of embossments and a plurality of recesses, said recesses on one plate being sized and arranged to complement the corresponding embossments on the other plate and when said plates are pivoted into surface-to-surface relationship, each embossment and recess combination having a thickness which is less than the thickness of the plate in which the recess is formed,

d. the embossments on each plate being positioned on that portion of the surface which extends away from and between the knuckles of the plate whereby the embossments on each plate provide reinforcement to the hinge plates at the points of greatest strain during use without increasing the combined thickness of the pair of hinge plates.

4. A hinge assembly as defined in claim 3 wherein all embossments have equal thickness and all recesses have equal depth.

5. A hinge assembly as defined in claim 3 wherein the thickness of the embossments in each plate is no greater than one-half of the thickness of the other plate.

6. A hinge as defined in claim 3 wherein the embossments of said plates include holes for receiving screws for mounting said hinge.