WO2009013712A2

WO2009013712A2 - Rotational damper hinge

Info

Publication number: WO2009013712A2
Application number: PCT/IB2008/052951
Authority: WO
Inventors: Itzik Ogen
Original assignee: Keter Plastic Ltd.
Priority date: 2007-07-23
Filing date: 2008-07-23
Publication date: 2009-01-29
Also published as: WO2009013712A3

Abstract

A rotational damper device comprising a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.

Description

ROTATIONAL DAMPER HINGE

FIELD

The invention relates to hinge assemblies.

BACKGROUND

Rotational damper hinges are typically used in applications where the speed of rotation of an object, such as, for example, a cover, a lid or a door, is desired to be controlled. For convenience hereinafter a rotational damper hinge will be referred to as a "damper hinge". Damper hinges generally comprise a hinge mechanism included in a casing filled with a high viscosity fluid, such as grease, or with a gel, which serves to reduce the speed of rotation of the object as it pivots around an axis. Damper hinges are typically used to substantially eliminate the crashing sound typically associated with closing of objects such as doors, covers and the like, and to substantially eliminate possible hazards arising from the closing of these objects. A rotational damper is described in US Patent No. US 6,687,921 "Toilet Seat Damper", which describes a "damping apparatus for a toilet seat and a toilet cover generally including a hinged frame and a pair of mirror image dampers disposed in the frame for coupling with the toilet seat and toilet cover and providing independent damped closure thereof. Each damper includes a housing having a chamber with a rotor therein, supporting vanes disposed in slots and pivotable therein for enabling inward and outward movement of the vanes for controlling flow of fluid there past in order to provide damping movement. A drawback in this rotational damper may be the use of many small parts, some of which may be difficult to manufacture, which may result in a damper which is expensive to manufacture."

Another rotational damper is described in US Patent No. 5,697,122 "Rotary Damper and Closure Device with such Rotary Damper", which describes "a rotary damper having a moving valve supported on a support projection radially outwardly projecting from a shaft of a rotating member which is rotably disposed in a chamber filled with a viscous fluid in a casing. Depending on the direction in which the rotating member rotates in the chamber, the movable valve opens or closes a fluid path defined between the movable valve and an inner circumferential surface of the casing. The movable valve may be supported on the support projection, which is of circular cross-sectional shape or radially movably supported on the support projection, which is of a rectangular cross-sectional shape. A disadvantage in this damper is that a relatively large force may be initially required to set the object in motion for closing, and/or that resistance may be encountered when the object is moved during opening." A third rotation damper is described in US Patent No. 6,550,073 B2 "Articulation for a Toilet Seat", which describes "an articulation for a toilet seat for securing a seat assembly to a ceramic body, wherein the lowering movement of the seat assembly may be braked with the aid of a damping means. The damping means is connected via an adapter member with the fastening means of the seat assembly, wherein adapter member and damping means form the rotation axis for the seat assembly. A drawback with this damper may be in the use of a spring clip to provide axial securing of toilet seat articulations. The spring clips may with time lose their elastic characteristics, or may be physically removed."

There is, therefore, a need for a rotational damper hinge comprising a small number of parts and relatively inexpensive to manufacture; does not use easily accessible, removable components for securing the object; and does not require great physical efforts from a person when opening or closing the object.

SUMMARY An aspect of some embodiments of the invention relates to providing a rotational hinge assembly adapted to dampen the rate at which an object pivots about an axis of rotation in the hinge assembly. An "object" may comprise a toilet seat, a toilet seat cover, a lid, a cover such as that of a storage box, a door, or any other item adapted to pivot about the axis of rotation. According to an aspect of some embodiments of the invention, the rotational hinge assembly, hereinafter referred to as "rotational damper hinge" or "damper hinge", comprises a housing with an inner chamber. The chamber is divided by a rotor into two cavities. Comprised in the chamber is a substantially high viscosity fluid, or optionally a gel. For convenience hereinafter, the substantially high viscosity fluid, or gel, may be referred to as "fluid".

In accordance with an embodiment of the invention, when the rotor rotates from an open position to a closed position, the volume in the substantially fluid-filled portion of the cavity is reduced. The fluid is compressed and subsequently forced to flow through a gap between the rotor wings and the chamber wall, towards a substantially fluid-free portion of the cavity. In accordance with an embodiment of the invention, the width of the gap determines a speed of rotation of the rotor, and a magnitude of damping provided by the hinge assembly. Initially, the gap width is such that the rotor is substantially not subject to any damping when the object begins to rotate about the axis of rotation. This allows the object to develop a moment of force for continued rotation on its own when subject to damping. Damping occurs when the gap width is substantially reduced relative to the initial gap width. In some embodiments of the invention, the magnitude of the damping effect may be varied during rotation by varying the gap width.

According to an aspect of some embodiments of the invention, the damper hinge is used with the housing fixed to a body and a shaft extending from the rotor fixed to the object. The shaft then rotates relative to the fixed housing. Optionally, the damper hinge is used with the housing fixed to the object and the shaft fixed to the body. The housing then rotates relative to the fixed shaft.

According to some embodiments of the invention, the damper hinge may be used with a "mirror-like" pair to dampen the rotation of two objects pivoting about the same axis of rotation. The direction of rotation of the rotor in the damper hinge is opposite to that in the mirror-like pair. An example of such application is to dampen the closing of a toilet seat and a toilet seat cover. The damper hinges are installed on the toilet body facing each other, the shaft of one damper hinge connected to the seat and side and the shaft of the second damper hinge attached to the cover. The housings are attached to the body. Optionally, in some embodiments of the invention, the housing on one damper hinge is fixed to the seat, and the housing of the second damper hinge is fixed to the cover. The shafts are attached to the body. Additionally or alternatively, in some embodiments of the invention, the housing of one damper hinge is fixed to the seat, and the shaft of the second damper hinge is fixed to the cover, or optionally, the shaft of one damper hinge is fixed to the seat, and the housing of the second damper hinge is fixed to the cover. Optionally, in some embodiments of the invention, two damper hinges comprising rotors with the same direction of rotation may be used.

There is provided, in accordance with an embodiment of the invention, a rotational damper device comprising: a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity. Optionally, the the vane is adapted allow fluid flow from the second cavity to the first cavity.

In some embodiments of the invention, the vane is adapted to limit fluid flow from the first cavity to the second cavity as the rotor rotates to a closed position. Optionally, the vane is further adapted to pivot to abut with the rotor as the rotor rotates to the closed position. In some embodiments of the invention, the vane is adapted to allow fluid flow from the second cavity to the first cavity as the rotor rotates to an open position. Optionally, the vane is further adapted to pivot in a direction of the wall of the chamber as the rotor rotates to the open position. In some embodiments of the invention, the wall of the chamber comprises a ridge. Optionally, the ridge comprises a slot adapted to slidingly receive the vane.

In some embodiments of the invention, the fluid comprises a viscosity greater than that of water. Optionally, the fluid is an oil. Optionally, the fluid is a gel. Optionally, the device comprises an o-ring adapted to substantially prevent leaking of the fluid.

In some embodiments of the invention, the device further comprises a shaft adapted to be attached to an object subject to rotational damping. Optionally, the shaft is attached to the rotor. Optionally, the device further comprises a housing adapted to rotate relative to the shaft.

Additionally or alternatively, the device further comprises an end section adapted to rotate relative to the shaft.

There is provided, in accordance with an embodiment of the invention, a method of rotational damping comprising: rotating a rotor comprising a rotor wing inside a chamber having a first cavity and a second cavity; and attaching a vane to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity. Optionally, the method further comprises allowing fluid flow from the second cavity to the first cavity.

In some embodiments of the invention, the method further comprises limiting fluid flow from the first cavity to the second cavity as the rotor rotates to a closed position. Optionally, the method further comprises pivoting the vane to abut with the rotor as the rotor rotates to the closed position. In some embodiments of the invention, the method further comprises allowing fluid flow from the second cavity to the first cavity as the rotor rotates to an open position. Optionally, the method further comprises pivoting the vane in a direction of the wall of the chamber as the rotor rotates to the open position.

In some embodiments of the invention, the wall of the chamber comprises a ridge. Optionally, the method further comprises sliding the vane into a slot comprised in the ridge.

In some embodiments of the invention, the fluid comprises a viscosity greater than that of water. Optionally, the fluid is oil. Optionally, the fluid is a gel. Optionally, the method further comprises substantially prevent leaking of the fluid using an o-ring.

In some embodiments of the invention, the method further comprises attaching a shaft to an object subject to rotational damping. Optionally, the method further comprises attaching the shaft to the rotor. Optionally, the method further comprises rotating a housing relative to the shaft. Optionally, the method further comprises rotating an end section relative to the shaft.

In accordance with an embodiment of the invention, there is provided an article of manufacture comprising a toilet seat cover, the toilet seat cover comprising a rotational damper device comprising: a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.

In accordance with an embodiment of the invention, there is provided an article of manufacture comprising a toilet seat, the toilet seat comprising a rotational damper device comprising: a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.

BRIEF DESCRIPTION OF FIGURES

Examples illustrative of embodiments of the invention are described below with reference to figures attached hereto. In the figures, identical structures, elements or parts that appear in more than one figure are generally labeled with a same numeral in all the figures in which they appear. Dimensions of components and features shown in the figures are generally chosen for convenience and clarity of presentation and are not necessarily shown to scale. The figures are listed below.

Figure 1 schematically shows an exploded view of an exemplary rotational damper hinge in accordance with an embodiment of the invention;

Figures 2a - 2d schematically show the operation of an exemplary damper hinge in accordance with an embodiment of the invention;

Figures 3 a and 3b schematically show a perspective view of two exemplary dampers adapted for use with two objects pivoting about a same axis of rotation, in accordance with an embodiment of the invention; and,

Figures 4a and 4b schematically show the exemplary damper hinge of Figure 3b in two possible mounting configurations, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION Reference is made to Figure 1, which schematically shows an exploded view of an exemplary rotational damper hinge 100 in accordance with an embodiment of the invention. Damper hinge 100 comprises a housing 116, substantially cylindrical in shape, which includes an inner chamber 134. Inner chamber 134 is adapted to be filled, partially or wholly, with a substantially high viscosity fluid such as grease, or optionally a gel. Extending from one end of housing 116 is an end section 122, a cylindrical extension of the housing, preferably of smaller diameter and of shorter height than housing 116. End section 122 comprises screw threads for tightly engaging a relief screw 124, which restricts the escape of fluid from chamber 134 by means of an O-ring 126, or other type of sealing ring. Relief screw 124 is adapted to allow a quantity of fluid to be removed from chamber 134 should the amount in the chamber be excessive.

Damper hinge 100 additionally comprises a rotor/shaft assembly 138. One side of assembly 138 comprises a rotor 136, an extension adapted to be inserted in chamber 134, enabling assembly 138 to be rotated in a clockwise and counter-clockwise direction. Two rotor wings, such as that shown at rotor wing 114, perpendicularly and oppositely extend from a rotor body 140 comprised in rotor 136. Turning of rotor 136 in one direction will compress the fluid in inner chamber 134. This action will force the fluid to flow through a gap (not shown) separating the edges of the rotor wings from curved surfaces projecting from chamber wall 128, such as that shown at projecting surface 121. In some embodiments of the invention, the projecting surfaces may be sloped such that width of the gap decreases as the rotor rotates in the direction of the compressed fluid. In accordance with an embodiment of the invention, rotation of the rotor in the direction of fluid compression, such that the fluid is forced through the gap, is rotation in the direction of a closed position. Rotation of rotor 136 in the opposite direction is rotation in the direction of an open position. The other side of assembly 138 comprises a shaft 106, an extension adapted to be attached to the object such that the object may be pivoted about an axis of rotation "A" 150 on a body. Optionally, shaft 106 may be attached to the body, either directly or through an adaptor, and the object pivoted about the axis of rotation on the body. Separating rotor 136 from shaft 106 are two disc-shaped surfaces 110 and 112, separated by an O-ring 108. Surfaces 110 and 112, and O-ring 108, are adapted to prevent fluid escape from inside the chamber of housing 116, while permitting freedom of rotation of assembly 138.

Comprised in chamber 134 are two vanes, such as that shown at vane 120. Vane 120 extends the height of housing 116, is wing-shaped, and is adapted to pivot inwards in the direction of chamber wall 128, and outwards in the direction away from the chamber wall towards the rotor. Rotation of rotor 136 towards the closed position compresses the fluid and causes the vanes to pivot outwards to abut with the rotor. Turning the rotor towards the open position causes the vanes to pivot inwards. In this manner, the vanes work like a one-way valve, adapted to allow fluid to pass through when in the open position and restricting fluid flow in the closed position. The vanes are slidingly attached to chamber wall 128 through slots in two ridges projecting from the chamber wall, such as that shown at slot 132 in ridge 130. The ridges are adapted to conform to the shape of the vanes when in the open and closed position.

A forward section 118 is a cylindrical extension of the housing, of diameter and height to tightly receive surfaces 110 and 112, and O-ring 108, without affecting the rotation of the assembly. Forward section 118 is located at the other end of housing 116, opposite end section 122. Securing of rotor/shaft assembly 138, with rotor 136 fitted inside chamber 128, is achieved by tightening a head section 102 unto the forward section 118. Head section 102 is adapted with a center hole 140 through which shaft 106 extends, enabling rotation of assembly 138. A washer bearing 104 is adapted to substantially allow rotation of assembly 138 when secured by head section 102.

Reference is made to Figures 2a - 2d which schematically show the operation of an exemplary damper hinge 200, in accordance with an embodiment of the invention. Damper hinge 200 comprises a housing 216, a chamber 234, chamber wall 228, projecting surfaces such as that shown at projecting surface 221, a rotor 236 including a rotor body 240 and rotor wings 214, two vanes such as that shown at vane 220, two slots such as that shown at slot 232, and two ridges such as that shown at ridge 230. Damper hinge 200, housing 216, chamber 234, chamber wall 228, projecting surface 221, rotor 236, vane 220, slot 232, and ridge 230, are the same or substantially similar to that shown in Figure 1 at 100, 116, 134, 128, 121, 136, 120, 132, and 130.

Figure 2a shows rotor 236 in the open position. Rotor wings 214 are abutting the ridges, for example ridge 230. The vanes, for example vane 220, are extended inwards in the direction of chamber wall 228, and abut one side of the ridge. Two cavities are comprised in chamber 234, one on each side of rotor 236, such as that shown at cavity 235. The cavities comprise a high viscosity fluid such as grease, or optionally a gel. Between chamber wall 228 and rotor wing 214 there is a gap 260. In the open position gap 260 is of maximum width.

In order to initiate rotational motion of Rotor 236 from the open position a force is imparted on the object, causing a rotational displacement of the object. For example, in accordance with some embodiments of the invention, there is an open toilet seat displaced by a user from a vertical position to a position where gravity pulls the seat towards a horizontal closing position, or optionally, a toilet seat cover.

Figure 2b shows rotor 236 after reaching a first position of rotation coinciding with the start of damping. Cavity 235 is substantially filled with fluid. Rotor 236 rotates through an angle α 237 towards projecting surface 221, the fluid in the cavity flows substantially freely through gap 260 from one side of cavity 235 to the other. In accordance with an embodiment of the invention, the width of gap 260 is a maximum throughout the rotational displacement represented by α 237, which ranges from 5 degrees - 45 degrees, for example, 30 degrees, relative to the open position. Figure 2c shows rotor 236 after reaching a position of rotation where damping is already experienced. Once rotor 236 reaches projecting surface 221, the width of gap 260 separating the projecting surface from rotor wing 214 decreases. In accordance with an embodiment of the invention, the width of gap 260 determines the speed of rotation of the rotor, and the magnitude of the damping provided. At this stage the fluid starts to be compressed by the rotor as the rate at which the fluid can flow through the reduced gap width decreases. The fluid pushes on the vanes, forcing them to extend fully outwards until they abut with rotor body 240. The continued pressure from the fluid being compressed maintains the vanes tightly abutting with the rotor body, acting as a one-way valve, such that fluid flow is restricted to the gap. The vanes are supported through abutment with a second side of the ridges. As the fluid continues to be compressed, the fluid flows through the gap from one side of the cavity to the other, and a damping effect is created. Rotor 236 continues to rotate counterclockwise, as fluid flows through the gap until rotor wing 214 abuts with the ridge opposite that of the open position. This position is the closed position.

Figure 2d shows rotor 236 after having reached the closed position and rotated clockwise back to the open position. The fluid which flowed through gap 260 is pushed by the rotor into the other cavity as the rotor returns to the open position. The vanes, acting as one way valves, pivot inwards under the pressure of the fluid being pushed by the rotor, allowing the fluid to flow through freely. This allows the rotor to be returned to the open position without experiencing any damping effect. In some embodiments of the invention, the rotation of the rotor from the open position to the closed position may be in a clockwise direction and rotation from the closed position to the open position in a counter-clockwise direction. In these embodiments of the invention damper hinge 200 is substantially a mirror-image of the presently described embodiment. Reference is made to Figures 3a and 3b, which schematically show a perspective view of two exemplary dampers adapted for use with two objects pivoting about a same axis of rotation in a body, in accordance with an embodiment of the invention. An example of this application may be where the body is a toilet and the two objects are a toilet seat and a toilet cover, respectively. Damper hinge 300 is adapted for mounting on the right side of the axis of rotation and damper hinge 301 is adapted for mounting on the left side of the axis of rotation.

Damper hinge 300 comprises a shaft 306, a housing 316, a head section 302, an end section 322, and a housing lever 319. Damper hinge 300, shaft 306, housing 316, head section 302, and end section 322 are the same or substantially similar to that shown in Figure 1 at 100, 106, 116, 102, and 122. Housing 316 comprises housing lever 319, a rectangular projection extending along the length of the housing, adapted to provide the required torque for pivoting the object about the axis of rotation. Damper hinge 300 is adapted such that rotation of shaft 306 is clockwise when rotating from the open position to the closed position, and counterclockwise when rotating from the closed position to the open position. Damper hinge 301 comprises a shaft 306, a housing 317, a head section 302, an end section 323, and an end lever 325. Damper hinge 301, shaft 306, housing 317, head section 302, and end section 323 are the same or substantially similar to that shown in Figure 1 at 100, 106, 116, 102, and 122. End section comprises an end lever 325, a rectangular projection extending along the length of the end section, adapted to provide the required torque for pivoting the object about the axis of rotation. Damper hinge 301 is adapted such that rotation of shaft 306 is counter-clockwise when rotating from the open position to the closed position, and clockwise when rotating from the closed position to the open position.

In some embodiments of the invention, instead of housing lever 319, damper hinge 300 is adapted with an end section comprising an end lever, similar to end lever 325 comprised in damper hinge 301. Optionally, instead of end lever 325, damper hinge 301 is adapted with a housing lever, similar to housing lever 319 comprised in damper hinge 300.

Reference is made to Figures 4a and 4b, which schematically show the exemplary damper hinge of Figure 3b in two possible mounting configurations, in accordance with an embodiment of the invention. Figure 4a shows damper hinge 301 in a mounting configuration wherein shaft 306 is fixed to an adapter 390 attached to a body, for example a toilet body, and the other components of damper hinge 301, which include head section 302, housing 317, end section 323 with end lever 325, are fixed in a cover 392, which may be a toilet seat cover. Opening and closing of cover 392 will result in relative motion of the components of the damper hinge relative to the fixed shaft. The rotor, which also remains fixed relative to adapter 390, rotates inside the chamber relative to the other damper hinge components.

Figure 4b shows damper hinge 301 in a mounting configuration wherein shaft 306 is fixed in a cover 393, which may be a toilet seat cover, and the other components of damper hinge 301, which include head section 302, housing 317, end section 323 with end lever 325, are fixed to an adapter 391 attached to a body, for example a toilet body. Opening and closing of cover 393 will cause shaft 306, and thereby the rotor, to rotate inside the damper hinge.

In accordance with some embodiments of the invention a fixed shaft mounting configuration similar to that shown in Figure 4a and/or a rotating shaft mounting configuration similar to that shown in Figure 4b may be used with damper hinge 300 in Figure 3 a.

In accordance with some embodiments of the inventions, damper hinges 300 and/or 301 may be used when two objects are to be pivoted about an axis of rotation. The damper hinges may be both mounted in a fixed shaft mounting configuration, or alternatively in a rotating shaft mounting configuration, or optionally, where one of the damper hinges is mounted in a fixed shaft mounting configuration and the other in a rotating shaft mounting configuration.

In the description and claims of embodiments of the present invention, each of the words, "comprise" "include" and "have", and forms thereof, are not necessarily limited to members in a list with which the words may be associated.

The invention has been described using various detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments may comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the invention that are described and embodiments of the invention comprising different combinations of features noted in the described embodiments will occur to persons with skill in the art.

Claims

1. A rotational damper device comprising:

a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and

a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.

2. The device of claim 1 , wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity as the rotor rotates to a closed position.

3. The device of claim 2 wherein the vane is further adapted to pivot to abut with the rotor as the rotor rotates to the closed position.

4. The device of claim 1 , wherein the vane is adapted to allow fluid flow from the second cavity to the first cavity.

5. The device of claim 4 wherein the vane is further adapted to pivot in a direction of the wall of the chamber as the rotor rotates to the open position.

6. The device of claim 1 , wherein the vane is adapted to allow fluid flow from the second cavity to the first cavity as the rotor rotates to an open position.

7. The device of claim 1 wherein the wall of the chamber comprises a ridge.

8. The device of claim 7 wherein the ridge comprises a slot adapted to slidingly receive the vane.

9. The device of claim 1 wherein the fluid comprises a viscosity greater than that of water.

10. The device of claim 1 wherein the fluid is an oil.

11. The device of claim 1 wherein the fluid is a gel.

12. The device of claim 1 further comprising an o-ring adapted to substantially prevent leaking of the fluid.

13. The device of claim 1 further comprising a shaft adapted to be attached to an object subj ect to rotational damping.

14. The device of claim 13 wherein the shaft is attached to the rotor.

15. The device of claim 13 further comprising a housing adapted to rotate relative to the shaft.

16. The device of claim 13 further comprising an end section adapted to rotate relative to the shaft.

17. A method of rotational damping comprising:

rotating a rotor comprising a rotor wing inside a chamber having a first cavity and a second cavity; and

attaching a vane to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.

18. The method of claim 17 further comprising limiting fluid flow from the first cavity to the second cavity as the rotor rotates to a closed position.

19. The method of claim 18 further comprising pivoting the vane to abut with the rotor as the rotor rotates to the closed position.

20. The method of claim 17 further comprising allowing fluid flow from the second cavity to the first cavity.

21. The method of claim 20 further comprising pivoting the vane in a direction of the wall of the chamber as the rotor rotates to the open position.

22. The method of claim 17 further comprising allowing fluid flow from the second cavity to the first cavity as the rotor rotates to an open position.

23. The method of claim 17 wherein the wall of the chamber comprises a ridge.

24. The method of claim 23 further comprising sliding the vane into a slot comprised in the ridge.

25. The method of claim 17 wherein the fluid comprises a viscosity greater than that of water.

26. The method of claim 17 wherein the fluid is oil.

27. The method of claim 17 wherein the fluid is a gel.

28. The method of claim 17 further comprising substantially preventing leaking of the fluid using an o-ring.

29. The method of claim 17 further comprising attaching a shaft to an object subject to rotational damping.

30. The method of claim 29 further comprising attaching the shaft to the rotor.

31. The method of claim 29 further comprising rotating a housing relative to the shaft.

32. The method of claim 29 further comprising rotating an end section relative to the shaft.

33. An article of manufacture comprising a toilet seat cover, the toilet seat cover comprising a rotational damper device comprising: a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.

34. An article of manufacture comprising a toilet seat, the toilet seat comprising a rotational damper device comprising: a rotor comprising a rotor wing adapted to rotate inside a chamber having a first cavity and a second cavity; and a vane attached to a wall of the chamber wherein the vane is adapted to limit fluid flow from the first cavity to the second cavity.