Patent Application
20090025181
1. Field of the Invention
The present invention relates generally to a hinge mechanism and more specifically to a self-closing hinge system for controlling a rate of rotation capable of being mounted to any device requiring closing such as a door or toilet seat wherein the hinge system slowly returns the device to a closed position through stored energy means.
2. Description of the Related Art
In many circumstances, it is desirable to provide a hinge mechanism which maintains a device, or a hinged member, in a predetermined open or closed position and further, when opened or closed, returns said hinged member to its predetermined positioned at a relatively slow and constant rate. This is particularly desirable in the case of such hinged members as toilet seats, cabinet doors, exterior doors, and flip-open type cellular telephones where a dampened return to a predetermined position is helpful to the user.
In some prior art self-closing hinge devices, a spring bias member is secured between the hinged member and the device whereby the hinged member is opened against the force of the spring member. When the hinged member is released the force provided by the spring acts to force the hinged member to its closed position. This simple type of self-closing hinge device is unsatisfactory in many cases because the hinged member is forced back too quickly, thus slamming it to its closed position. Where devices of this type are installed on, for example, toilet seats, the seat slams down against the toilet base, thereby causing a great deal of noise. Furthermore, the seat is being forced downwardly (closed) by the spring tension at all times, thereby requiring it to be held in its up or open position.
To overcome these difficulties, some prior art hinge mechanisms have employed dampening systems to inhibit the quick closing tendencies of spring-biased self-closing hinges. Prior art dampening hinge mechanisms comprise complex combinations of axial elements, cams, viscoelastic fluids, bearings and the like to provide hinges wherein the opening and or closing speed of the hinge mechanism can be regulated.
Many prior art dampening mechanisms that utilize dampening systems unnecessarily limit or regulate the opening speed of the hinge, which is highly undesirable when said hinge is utilized in conjunction with a door or cabinet door. In such environments it is preferable to be able to open the door at an unregulated speed wherein the hinge “keeps up” with the rotational motion of the door and then slowly closes the door.
Accordingly, there is a need in the art for a self-closing hinge apparatus that is simple and economical to manufacture and produce and that does not limit its rate of rotation in a first direction, while maintaining the ability to regulate its rate of rotation in a second direction.
The present invention provides a self-closing hinge suitable for use in a variety of applications where it is desirable to provide for automatic closing of a hinged member in a delayed or slow fashion. The invention described and claimed herein may be advantageously employed in toilet seats or lids, ingress and egress doors, cabinet doors or even flip-top style cellular phones.
The invention includes a generally cylindrical outer casing or housing that partially encloses a rotatable shaft that may be secured to a hinged member to effect the rotation thereof. The shaft is disposed within a recess in a cylindrical coupler that is engaged by the shaft during rotation in a first direction—generally an “open” rotational direction—and that engages the shaft to rotate it in a second direction—generally a “closed” rotational direction.
The coupler is secured to a torsional spring that acts against the open rotation of the shaft and thereby forces the coupler to rotate in a closed direction. Additionally, a rotatable inner casing, which is generally cylindrical, may be disposed within the outer casing in close proximity thereto, such that a high viscosity fluid may be disposed therebetween. The coupler includes a race around a portion thereof that is engaged by a clutch bearing. The clutch bearing engages the inner casing and the coupler when the coupler is rotating in the “closed” direction so that the coupler rotates closed against the force of the inner casing rotating relative to the outer casing.
In this fashion, the coupler, and thus the shaft that is engaged thereby, slowly rotate to a closed position once an opening rotational force ceases to be applied to the shaft.
Other features and advantages of the present invention will become apparent from the detailed description of the preferred embodiments herein below in conjunction with the drawing Figures appended hereto.
Referring now to drawing
A generally cylindrical and tubular inner casing 60 is disposed radially inwardly of, and in close proximity to outer casing 30. A bottom end 62 of casing 60 abuts bottom end cap 40. A Top end 64 of casing 60 is engaged by an annular fluid seal 70 that rests in an annular groove 54 in top end cap 50. In one embodiment of the present invention, a high viscosity fluid is disposed between rotatable inner casing 60 and outer casing 30 to inhibit the rotation of inner casing 60 relative to outer casing 30. Fluid seal 70 prevents the escape of the high viscosity fluid between inner casing 60 and outer casing 30. Additionally, bottom end cap 40 may also have an annular groove 44 that is engaged by a fluid seal 70 to prevent escape of the high viscosity fluid. As one example, high viscosity fluid may comprise a pure silicon fluid having a viscosity of 20,000,000 centiStokes (cSt) that is disposed in the generally annular area between rotatable inner casing 60 and outer casing 30. It should be noted that a range of fluid viscosities may be employed in various embodiments of the present invention, depending upon the dampening effect desired for a particular hinge application. More viscous fluid would act to provide a more slowly closing hinge.
Referring now to
Coupler 80 may further include a spring aperture 86 into which a first end 112 of a torsional spring 110 is inserted. As shown in
As best seen in
Additionally, as seen in
In a further embodiment of the present invention inner casing 60 and clutch bearing 100 are omitted entirely so that the closing force provided by torsional spring 110 is not dampened. Additionally, in one embodiment of the invention, pin 22 of shaft 20 are formed of a single piece of material such that pin 22 and shaft 20 are unitary in construction. Additionally, pin 22 is not required to be shaped as a pin, but may be shaped as any protrusion suitable for engaging with contact portion 88 of coupler 88.
In a yet further embodiment of the invention coupler 80 and shaft 20 may be an integral or unitary assembly such that no contact portion 88 or pin 22 are required for operation. In this embodiment of the invention, the coupler 80 and shaft 20 unit always rotate open and closed together, so that when rotating in a closed direction, the dampening force provided by the relative motion of inner casing 60 rotating against outer casing 30 is always present.
While the present invention has been shown and described herein in what are considered to be the preferred embodiments thereof, illustrating the results and advantages over the prior art obtained through the present invention, the invention is not limited to those specific embodiments. Thus, the forms of the invention shown and described herein are to be taken as illustrative only and other embodiments may be selected without departing from the scope of the present invention, as set forth in the claims appended hereto.
