US3546736A - Gravity operated door hinge - Google Patents

Description

Dec. 15, 1970 J. s. BOOTH O 3,546,736

GRAVITY OPERATED DOOR HINGE Filed Aug. 19, 1968 INVENTOR:

JOHN S. BOOTH ATTOR N EYS United States Patent 3,546,736 GRAVITY OPERATED DOOR HINGE John S. Booth, 3314 Fairview, Dallas, Tex. 75229 Filed Aug. 19, 1968, Ser. No. 753,422 Int. Cl. Ef 1/07 US. Cl. 16-153 4 Claims ABSTRACT OF THE DISCLOSURE A gravity operated door hinge including a lower fixed member having a sleeve surrounded by a pair of upstanding, helical, inclined, camming shoulders and an upper rotating member having a stud mating with the lower member sleeve and helical upper camming surfaces engaging the camming shoulders. The upper carnming surfaces are positioned so that they engage the inclined camming shOulders when the door is closed, to provide positive pressure seating the door in its closed position. The camming shoulders have a flat portion at their upper ends, so that when the door is opened wide the camming surfaces are in engagement therewith to eliminate the torque pressing the door towards the closed position.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to door hinges, and more particularly, to gravity-operated door hinges fgr one-way swinging doors which are biased to the closed position.

Prior art It has been known to provide a two-piece door hinge having coacting helical camming tracks. The weight of the door on the upper member of. such a hinge causes the upper member to be urged downward around the camming track or the lower member, thus closing the door.

Such hinges in the prior art have not, however, provided for a positive pressure against the door in the closed position. It may be desired to provide such pressure in any number of applications. For example, a definite sealing of the closure is desired for the doors of a refrigerating unit.

SUMMARY OF THE INVENTION It is therefore an object of this invention to provide a gravity hinge having coacting camming surfaces which will exert a continuous pressure tending to retain a door in its closed position. In one aspect of the invention, the camming surfaces are aligned so that the upper cam rests on inclined portions of the lower cam when the door is closed, thus creating a rotational moment pressing the door in place.

In a further aspect of the invention, the camming surfaces of a hinge are so shaped that, when the door is opened wide, the rotational torque tending to close the door is eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the present invention and for further objects and advantages thereof, reference may now be had to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a plan view of the fixed member of a twopiece hinge embodying the present invention;

FIG. 2 is a plan view of the rotating member of the same hinge;

FIG. 3 is a plan view of the hinge of FIGS. 1 and 2 in operating position on a door, with the door closed; and

3,546,736 Patented Dec. 15, 1970 DESCRIPTION OF A PREFERRED EMBODIMENT The fixed member of the hinge, indicated generally by the reference numeral 10 in FIG. 1, has a mounting plate 12 having a sleeve 16 extending outwardly therefrom. A hole 14 is provided in the plate 12 at the center of the sleeve 16. Situated circumferentially about sleeve 16 are two matched upstanding shoulders 18:: and 18b. The upper surfaces of shoulders 18a and 18b are inclined, so that they form generally helical camming tracks. Located at the upper ends of the camming tracks formed by shoulders 18a and 18b are fiat surfaces 20.

The mounting plate 12 is provided with holes 22 so that suitable mounting means such as screws may be used to fasten the plate to a floor or other fixed frame defining an aperture to be closed by a door.

The rotating member of the two-piece hinge, generally indicated by the reference numeral 24 in FIG. 2, has a mounting bracket 26, from which a stud 28 extends. The stud is dimensioned so that it fits slidably and rotatably into sleeve 16.

Arrayed about stud 28 are two raised camming surfaces 30a and 3011 which are complementary to camming shoulders 18a and 18b. These upper camming surfaces 300: and 30b are inclined so that they can ride on the camming tracks presented by shoulders 18a and 18b.

The bracket 26 is provided with holes 32, so that the bracket may be secured to a door by suitable fastening means. The member 24 is provided with a vertical extension 33, through which a screw may be threaded to provide additional bracing of the member 24 to the door.

The fixed member 10, as well as the rotating member 24, may be of unitary construction, formed from a single piece of a suitable material such as a plastic.

In operation, as illustrated by FIGS. 3 and 4, the fixed member 10 is attached to the lower part of a frame 34 defining a door opening, and the rotating member 24 is secured to the lower corner of a door 36 adjacent the side of the door to be pivoted. The stud 28 is positioned within sleeve 16, so that relative rotation and axial movement is permitted between fixed member 10 and rotating member 24. The weight of the door upon the fixed member 10 constantly urges the camming surfaces 30a and 30b downward against the camming shoulders 18a and 18b. As the rotating member 24 moves downward along the camming shoulders 18a and 18b, it also rotates to close the door to which it is attached. Thus, when the door is open, the force of gravity acting on the door produces a torque about the stud 28 tending to cause the door to close.

An important feature of the invention is the rotational alignment of the camming surfaces 30a and 30b with respect to the upstanding shoulders 18a and 18b, and with respect to the door. This alignment is such that, when the door has been rotated into its closed position, the camming surfaces 30a and 30b have not completely traveled downward along the camming shoulders 18a and 18b to rest on the mounting plate 12, as shown in FIG. 3.

Thus, when the door is closed, the weight of the door transmitted through the camming arrangement exerts a constant pressure retaining the door in its closed position. This condition is indicated in FIG. 3, which shows a gap 38 between the camming surface 30 and the mounting plate 12.

The device is also constructed so that the door to which the hinge is attached may be swung wide to a point where the bias exerted through the camming arrangement is eliminated. When the door is opened Wide enough to place the camming surfaces 30a and 30b in contact with only the flat surfaces 20, as shown in FIG. 4,

no rotational torque about the stud 28 is created by the weight of the door. Thus the door is freed from the bias normally exerted through the hinge.

A suitable stop, not shown, restraining the door from rotation beyond the point at which the surfaces 30a and 30b rest on the flat areas 20 should be provided. Such a stop serves to prevent the surfaces 301: and 30b from dropping off shoulders 18a and 18b onto the plate 12.

Having described the invention in connection with certain specific embodiments thereof, it is to be understood that further modifications may now suggest themselves to those skilled in the art and it is intended to cover such modifications as fall within the scope of the appended claims.

What is claimed is:

1. A gravity operated hinge for rotatably mounting a door in a frame to be closed against a door jam, comprising:

a fixed hinge member adapted for attachment to the frame and having a base, a vertically extending sleeve, and an upstanding generally helical camming shoulder terminating at a slope to the base at a first angle with respect to the longitudinal axis through said member around said sleeve, and

a rotatable hinge member adapted for attachment to said door and having a vertically extending stud slidably mountable in said sleeve and helical camming surfaces terminating at a leading edge at a second angle with respect to the longitudinal axis of said member greater than the first angle to engage said camming shoulders such that when said door is closed the camming surfaces engage the fixed hinge member on inclined portions of said-shoulder.

2. The combination of claim 1 wherein upper portions of said camming shoulders are perpendicular to the axis of said sleeves.

3. A gravity operated hinge for rotatably mounting a door in a frame to close against a door jam, comprising: a fixed hinge member adapted for attachment to the frame and having a base, a vertically extending sleeve, and a pair of upstanding generally helical camming shoulders circumferentially about and formed as a part of said sleeve and terminating at a slope to said base at a first angle with respect to a longitudinal axis through said member, and a rotatable hinge member adapted for attachment to said door and having a vertically extending stud slidably and rotatably mounted in said sleeve and a pair of upstanding generally helical camming surfaces arrayed about and displaced from said stud in a manner to produce a rotating movement on said door, said camming surfaces terminating at a leading edge at a second angle with respect to the longitudinal axis of said member greater than the first angle to cause engagement with said camming shoulders such that when said door is closed the camming surfaces engage the fixed hinge member on inclined portions of said shoulders.

4. A gravity operated hinge for rotatably mounting a door in a frame as set forth in claim 3 including means to reduce the rotating moment on said door to zero when in a wide open position.

I References Cited UNITED STATES PATENTS 2,904,824 9/1959 Kuehl 16-153 3,083,402 4/1963 Foltz 16-153 3,113,649 12/1963 Wargo 16153 3,398,881 4/1968 Hentzi et a1. 16-153 3,398,487 8/1968 Mtyas 16153 BOBBY R. GAY, Primary Examiner D. L. TROUTMAN, Assistant Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 546 ,736 Dated December 15 1970 lnvgntofls) John S Booth It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 38, "or" should read of Column 3, line 37, "sleeves" should read sleeve Column 4, line 33, "3 398 ,881" should read 3 ,378 ,881

Signed and sealed this 4th day of Ma 1 1971 (SEAL) Attest:

EDWARD M FLETCHER ,JR WILLIAM E SCHUYLER, JR Attesting Officer Commissioner of Patents

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