Abstract:
A linear damper includes a conical housing with a friction cone in the housing and a rod extending therethrough and axially moveable relative thereto. The friction cone is axially moveable in the housing and radially expandable and contractible to provide clamping force against a rod when the rod is moved in one axial direction and to relieve clamping force from the rod when the rod is moved in the opposite axial direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present regular United States Patent Application claims the benefits of U.S. Provisional Application Ser. No. 60/736,209, filed on Nov. 14, 2005. 

   FIELD OF THE INVENTION 
   The present invention relates generally to movement dampers and, more particularly, the invention pertains to linear dampers providing high resistance. 
   BACKGROUND OF THE INVENTION 
   Movement dampers have many applications and uses for controlling the movement of things. Dampers are used extensively in automotive applications for controlling the movement of glove box doors, cup holders, assist handles and the like. Dampers are often used to control the natural gravitational movement of such components, and to provide a desired feel to the movement of the component being controlled. Uses for dampers in assemblies other than automobiles are also known widely, such as, for example, and not by way of limitation, furniture doors and drawers, appliances, electronic components and other assemblies that have doors, drawers and other components that open or close, move in and out, fold up and down, etc. 
   It is known to provide center consoles between occupant seats in automobiles, trucks, SUV&#39;s and the like. In larger vehicles, the center console can be quite large. Often a door is provided on the top of the console having a hinge at the back and a latch at the front. The door is opened by lifting the front edge upward, thus pivoting the door on the hinge at the back. Such console doors can be both bulky and heavy. Opening can be assisted by springs or the like so that the vehicle occupant is not burdened with lifting the entire weight of the door. Movement dampers can be used to lessen the closing force from the weight of the door, thereby preventing the door or cover from falling shut forcefully, potentially causing damage. 
   It is often desirable for dampers of this type to work in confined spaces, yet provide significant resistance to the gravitational movement of the object. Limited space can require straight line movement. It is known for damping requirements to be in one direction only, with the damper providing significant resistance in the desired direction and with little or no resistance or damping effect in the opposite direction. 
   In automobile applications it is desirable for a damper to work effectively without adjustment and to perform satisfactorily through many cycles without failing. Also, it is desirable for the damper to be small and operate effectively in a confined space, to minimize the intrusion in the occupant space of the vehicle. 
   Accordingly, there is need for improved linear dampers. 
   SUMMERY OF THE INVENTION 
   The present invention provides a linear damper with an engaging/disengaging structure whereby the damper provides significant resistance to the movement of a rod in one direction but little resistance to movement of the rod in the opposite axial direction. 
   In one aspect thereof, the present invention provides a linear damper with a damping assembly and a rod extending through the damping assembly, the damping assembly and the rod configured and arranged for relative axial movement therebetween. The damping assembly includes a friction member therein disposed adjacent the rod. The friction member is actuated by movement of the rod in one axial direction to provide clamping force against the rod and by movement in an opposite axial direction to release clamping force applied against the rod. 
   In another aspect thereof, the present invention provides a linear damper with a conical housing, a friction cone disposed for axial movement in the housing and a rod extending through the friction cone and the housing. The friction cone is expandable and contractible upon axial movement in the conical housing to apply and release clamping pressure against the rod when relative axial movement occurs between the rod and the housing. 
   In a further aspect thereof, the present invention provides a linear damper with a damping assembly including a conical housing and a cap defining an axial opening therethrough. A friction cone is disposed in the housing and axially movable therein. The friction cone has an axial slit from one end thereof to the other end thereof. A rod extends through the housing, the cap and the friction cone in the housing, and is movable axially relative to the friction cone. 
   An advantage of the present invention is providing a linear damper that operates in a small space. 
   Another advantage of the present invention is providing a linear damper that is simple and inexpensive to manufacture and supply. 
   Still another advantage of the present invention is providing a linear damper that provides damping in one direction for movement of a rod, with little or no damping in an opposite direction of movement. 
   Yet another advantage of the present invention is providing a linear damper that requires little or no adjustment and can operate through many cycles of operation. 
   Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a linear damper in accordance with the present invention; 
       FIG. 2  is a longitudinal cross-sectional view of the linear damper shown in  FIG. 1 ; 
       FIG. 3  is a perspective view of a friction cone for the linear damper of the present invention; and 
       FIG. 4  is a perspective view of an automobile console having linear dampers in accordance with the present invention. 
   

   Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use herein of “including”, “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof, as well as additional items and equivalents thereof. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring now more specifically to the drawings and to  FIG. 1  in particular, numeral  10  designates a linear damper in accordance with the present invention. While linear dampers of the present invention are expected to have a variety of advantageous applications and uses, one particularly advantageous use is to control the closing movement of automobile console doors.  FIG. 4  illustrates an automobile console  12  having a base or bin  14  and a cover  16 . Cover  16  is connected to bin  14  by a hinge  18 . Two linear dampers  10  of the present invention are illustrated to control closing movement of cover  16 . Console  12  is merely one example of a suitable use, and the description thereof to follow should not be considered as a limitation on the application and use of the present invention. 
   Damper  10  includes a damping assembly  20  and a rod  22  axially movable relative to damping assembly  20 . 
   Rod  22  is a substantially linear, elongate body having a base  24  at one end thereof and a head  26  at an opposite end thereof. The shapes, sizes and the like of base  24  and head  26 , as well as the length and thickness of rod  22 , can be selected for the particular application and use of the present invention. For example, head  26  can be configured with a curved surface as shown for rolling type engagement with a surface pushing thereagainst in a pivotally rotational movement, such as the engagement of damper  10  with cover  16  of console  12 . Further, base  24  and head  26  can be configured to limit axial movement of rod  22 , so that rod  22  cannot slide completely through damping assembly  20  inadvertently. Rod  22 , base  24  and head  26  can be made of injected molded plastic or the like. 
   Damping assembly  20  includes a housing  30  and a cap  32 . A friction cone  34  is disposed in housing  30 . Housing  30  and cap  32  can be injection molded plastic or other suitable material, assembled in known manner. 
   Housing  30  is a conically shaped structure, at least with respect to the inside thereof, and has a tapered sidewall  36  defining an opening  38  at the bottom there of. In the exemplary embodiment, several flanges  40 ,  42  and/or mounting tabs  44 ,  46  are provided for installation and securement of damper  10  in its operating position within an assembly, and for providing desired levels of rigidity and strengthening. 
   Cap  32  closes an open top of the conically shaped housing sidewall  36 , and has an opening  50  in alignment with opening  38  in housing  30 . Rod  22  is extended slidably through openings  38  and  50 . Various configurations for attaching cap  32  to housing  30  can be used, and in the exemplary embodiment a channel  52  in cap  32  receives an upper edge  54  of housing  30 . Sonic welding, adhesive, frictional engagement and the like all can be used to secure cap  32  to housing  30 . 
   Friction cone  34  includes an outer shell  60  and an inner liner  62 . Shell  60  can be made of a plastic or other similar material and is shaped to fit in conically shaped housing  30 . Liner  62  is rubber, either natural or synthetic such as a thermoplastic or neoprene, with a high coefficient of friction relative to the material of rod  22 . Liner  62  is also conically shaped so as to fit within shell  60 . 
   Shell  60  and liner  62  have axial slots  64 ,  66 , respectively extending from one end thereof to the other end thereof. In the exemplary embodiment shown, slots  64  and  66  are aligned one with the other. An axial length of friction cone  34  is slightly less than a length of an interior volume  68  defined by housing  30  so that friction cone  34  can move axially slightly in housing  30 , either toward or away from the narrow end of conically shaped volume  68 . 
   The operation of damper  10  will now be described with reference particularly to  FIG. 2 . With damping assembly  20  in a substantially fixed position, such that housing  30  and cap  32  are relatively immovable, rod  22  is moved axially by apparatus to which it is operatively connected. For example, as cover  16  of console  12  is closed, a portion of the cover pushes against rods  22  of the two dampers  10  shown in  FIG. 4 . As rod  22  moves downwardly in conically shaped housing  30 , moving in a direction from opening  50  in cap  32  toward opening  38  in housing  30 , friction cone  34  is dragged downwardly in conically shaped housing  30 . Accordingly, as each moves more deeply into the narrowed end of interior volume  68 , shell  60  and liner  62  are squeezed, narrowing slightly the openings defined by slits  64 ,  66 . Greater clamping force is applied against rod  22 , and the friction of rod  22  against liner  62  resists axial movement of rod  22 . Accordingly, damping effect is provided on an object or thing that pushes against rod  22 , urging it downwardly in conical housing  30 . 
   When rod  22  is moved in an axial direction opposite to that just described, that is with rod  22  being moved from opening  38  of housing  30  toward opening  50  of cap  32 , friction cone  34  is moved upwardly within conical housing  30 . Accordingly, shell  60  and liner  62  are each allowed to expand slightly in the wider area of housing volume  68 , thereby increasing the widths of slots  64  and  66 . Clamping force against rod  22  is released, and minimal resistance to axial movement of rod  22  is provided. 
   Springs or other return means can be used to move rod  22  to a desired home location. For example, a spring can be used surrounding rod  22  between head  26  and cap  32 . Alternatively or conjunctively, a spring can be used operating against base  24  from beneath to move rod  22  upwardly. Other configurations also can be used. For example, the axial end of the rod, such as head  26 , can be secured to the device being controlled so that damper  10  provides damping in one direction and in the opposite direction provides little or no damping while rod  22  is being pulled to a desired start position. 
   Further, while described herein as having damping assembly  20  fixed and rod  22  movable, it should be understood that operation and function of damper  10  requires only relative movement between damping assembly  20  and rod  22 . Accordingly, in some installations and uses it may be advantageous for rod  22  to be fixed and for damping assembly  20  to move relative to rod  22 . As a further alternative, each damping assembly  20  and rod  22  can move either in opposite directions or in a same direction but at different speeds, such that relative movement occurs between damping assembly  20  and rod  22 . 
   It should be understood that the use of slits  64 ,  66  and the enablement of axial movement of friction cone  34  in housing  30  enhance both the damping effect that can be generated from clamping forces of liner  62  against rod  22 , and the rapid disengagement of clamping force. However, a damper of the present invention can be configured and used with other means for applying a compressive or clamping force of inner liner  62  against rod  22 . 
   Variations and modifications of the foregoing are within the scope of the present invention. It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art. 
   Various features of the invention are set forth in the following claims.