Abstract:
A detachable and adjustable damper hinge attachment for connection to pre-installed hinge hardware to dampen the closing motion of a swinging cabinet door. The attachment comprises a housing and a spring damper assembly slidingly and removably engaged with the housing. The housing includes an attachment means for detachable engagement with a hinge body. The spring damper assembly extends from the housing and contacts a portion of the hinge to which the door is mounted. One embodiment positions the spring damper assembly to more perpendicularly meet the door portion of the hinge. Another embodiment includes an adjustment knob for adapting the contact point of the spring damper assembly.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to damping mechanisms slowing the closure of cabinet door hinges. In particular, the invention relates to a detachable, adjustable, and reusable attachment for connection to pre-existing hinge assemblies that provides a damped door closure. 
       BACKGROUND OF THE INVENTION 
       [0002]    In the field of cabinetry and mill work a pervasive problem is uncontrolled closure of doors. Uncontrolled closure often results in slamming of cabinetry doors creating unwanted noise and premature wearing of cabinet hinges and cabinet faces. The art has responded generally to this problem by providing damping mechanisms. 
         [0003]    Damping mechanisms are generally comprised of a spring loaded piston contained in a fluid filled cylinder for engagement with the back side of the cabinet door. In the prior art, the damping mechanism is often very close to the pivot axis of the hinge. Such placement increases the force perpendicular to the piston rod on closure of the cabinet door thereby wearing the piston rod and the seals which contain the damping fluid. Failure of the seals or the piston rod thus shortens the life cycle of the entire hinge because of the failure of the damping piston. 
         [0004]    Premature failure is also caused by the inability of prior art hinges to adjust to the weight of the cabinet door on which they are employed. 
         [0005]    U.S. Pat. No. 4,190,925 to Koivusalo discloses a damped hinge. A first hinge plate is attached to the door and a second to the door frame. The first hinge plate is provided with a pair of guide sleeves in which a force-transmitting rod is guided for movement in a direction parallel to the hinge axis. A helical cam attached to the second hinge plate and the piston rod follows a slot when the door swings and moves the piston rod. The piston rod is housed vertically thus adding bulk to the hinge assembly. Since the hinge is integral to the damper, failure of the damper requires replacement of the hinge. Further, the angle of contact of the hinge with the damper is extreme, leading to premature wear and failure. 
         [0006]    U.S. Pat. No. 5,383,253 to Lin discloses a hydraulic buffer hinge. The device couples a cushion spring connected to two swinging plates with a hydraulic buffer to slow the return stroke of a swinging door. The cushion spring is aligned parallel to the pivot axis of the hinge while the piston of the hydraulic buffer is aligned perpendicularly to the pivot axis of the hinge. The damping force of the self-contained hydraulic buffer is not adjustable. Upon failure, the entire hinge assembly requires replacement. 
         [0007]    U.S. Pat. No. 6,928,699 to Sawa discloses an automatic closing door hinge mechanism. A first wing plate includes a cylinder and a piston while a second wing plate includes an operation rod engaged with the piston. A cam is formed on the piston. An engaging part provided on the operation rod is movable in the cam. A sphere on the outer surface of the piston moves in a lengthwise groove in the cylinder to allow the piston to slide within the cylinder. Impact of the door closing is pneumatically damped within the cylinder. The apparatus is bulky and requires replacement upon failure of the piston. 
         [0008]    Referring to  FIGS. 1A and 1B , the prior art also includes “piggy back” type damper arrangement  5000  designed to attach to hinge arm  6001  of recessed hinge arrangement  6000 . The placement of damper arrangement  5000  in the prior art is on top of hinge arm  6001  and adjacent to hinge plate  6003 . The placement allows for contact of absorber  5003  with hinge plate  6003  for approximately 20 degrees of travel of hinge  6000 . Because of the 20 degree hinge travel, the throw of absorber  5003  is extremely short and relatively ineffective at slowing the closure of a typical cabinet door. The addition of damper arrangement  5000  more than doubles the total height of hinge arm  6001  located in the cabinet thereby interfering with storage space and cabinet use. 
         [0009]    Further, when the damper mechanism fails, the entire hinge assembly must often be replaced. Removing the entire cabinet door and replacing the hinge instead of repairing it increases the cost of replacement. 
         [0010]    Thus, there is a need for a damper hinge device that is compact and removable. 
         [0011]    There is also a need for a damper hinge device that extends the life cycle of the mechanism and the surrounding cabinetry. 
         [0012]    There is also a need for a damper hinge device which is capable of contact point adjustment to provide for various applications. 
         [0013]    It is also desirable to effectuate a damped hinge mechanism which extends the operational contact angle thereby allowing for extended contact and more effective door closure. 
         [0014]    It is also desirable to effectuate a damper hinge mechanism with a low profile to reduce interference with operation and conserve space. 
       SUMMARY OF INVENTION 
       [0015]    In a preferred embodiment, the damper hinge mechanism comprises a body having a connector portion and a housing portion, a spring damper assembly slidingly and removably engaged with the interior of the housing portion. 
         [0016]    The spring damper assembly comprises a cylinder slidingly engaged with a piston and a piston rod. The cylinder is filled with a damping fluid such as mineral oil surrounding the piston rod and a spring biasing the piston. The cylinder includes a flexible tip for engagement with the hinge part mounted on the cabinet door. In various embodiments, the flexible tip is a dense energy absorbing foam rubber, rubber, or plastic. 
         [0017]    In one embodiment, the connector portion includes a fastening hook and a plurality of support abutments for removable engagement with a standard hinge body. In this embodiment, the housing portion is angled with respect to the connector portion to engage the hinge part mounted on a swinging door at an angle which reduces stress on the piston and cylinder. 
         [0018]    In another embodiment, the connector portion includes a securing hook, an adjustment hole to allow a user to adjust the hinge, and a cam locking mechanism. In this embodiment, the housing portion has a gap along the axis of the housing portion to reduce weight and material costs. This embodiment further comprises an adjustment knob for adjusting the contact point and the compressive strength of the spring damper assembly with a hinge part mounted on a swinging door. The piston rod is removably supported by the adjustment knob. The adjustment knob is threaded into the housing portion, providing axial adjustment for the spring damper assembly. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The disclosed embodiments will be described with reference to the accompanying drawings. Like pieces in different drawings carry the same number. 
           [0020]      FIG. 1A  is a side view of a damper of the prior part. 
           [0021]      FIG. 1B  is a side view of a damper of the prior art. 
           [0022]      FIG. 2  is an exploded isometric view of a preferred embodiment. 
           [0023]      FIG. 3A  is a top view of a preferred embodiment attached to a hinge. 
           [0024]      FIG. 3B  is a free body diagram of the forces acting on a damper of the prior art. 
           [0025]      FIG. 3C  is a free body diagram of the forces acting on a spring damper assembly of a preferred embodiment. 
           [0026]      FIG. 4A  is a top view of a preferred embodiment attached to a pre-mounted hinge at an open position. 
           [0027]      FIG. 4B  is a top view of a preferred embodiment attached to a pre-mounted hinge at an impact position. 
           [0028]      FIG. 4C  is a top view of a preferred embodiment attached to a pre-mounted hinge at a closed position. 
           [0029]      FIG. 5  is an exploded isometric view of a preferred embodiment. 
           [0030]      FIG. 6  is a detail elevation view of a connector portion of a preferred embodiment. 
           [0031]      FIG. 7A  is a top view of a preferred embodiment attached to a pre-mounted hinge at an open position. 
           [0032]      FIG. 7B  is a top view of a preferred embodiment attached to a pre-mounted hinge at an impact position. 
           [0033]      FIG. 7C  is a top view of a preferred embodiment attached to a pre-mounted hinge at a closed position. 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    Referring to  FIG. 2 , attachment  10  comprises body  100 , receiver  500 , and spring damper assembly  400 . Body  100  has connector portion  200  and housing portion  300 . Connector portion  200  has base  201 , attached to housing portion  300 , side  202 , side  203 , end  204 , and end  205 . Connector portion  200  extends generally radially from housing portion  300 . Side  202 , end  205 , and side  203  form a generally rectangular channel at end  205 . Side  202 , end  204 , and side  203  form a generally rectangular channel at end  204 . Fastening hook  207  and support  217  are attached to base  201 . Housing portion  300  is off-set with respect to connector portion  200 . 
         [0035]    Base  201  has support abutments  209 ,  210 ,  215 , and  211 , all of which are angled to facilitate the off-set position of housing portion  300  and are adjacent to side  202  attached to base  201 . Support abutment  215  is adjacent to side  202  and fastener hook  207 . Base  201  further has support abutments  212 ,  213 ,  216 , and  214 , all of which are angled to facilitate the off-set position of housing portion  300  and are adjacent to base  201  and side  202 . Support abutment  216  is adjacent to side  203  and fastener hook  207 . Support abutment  209  is positioned adjacent to side  202 , generally opposite from support abutment  212  adjacent to side  203 . Support abutment  210  is positioned adjacent to side  202 , generally opposite support abutment  213  adjacent to side  203 . Support abutment  211  is positioned adjacent to side  202 , generally opposite support abutment  214  adjacent to side  203 . 
         [0036]    Housing portion  300  has spring damper end  302 , inside surface  303 , and outside surface  304 . 
         [0037]    In a preferred embodiment, body  100  is made of a durable plastic, but can be made of other rigid materials such as cast aluminum, metal, metal alloy, or zinc die cast. 
         [0038]    Receiver  500  has flange  501 , barrel  502 , inside surface  507 , and outside surface  506 . Flange  501  has hole  503  and slots  505 ,  508 , and  509  to slidingly receive spring damper assembly  400 . Receiver  500  is inserted into hole  306  and outside surface  506  is frictionally engaged with inside surface  303  of housing portion  300 . 
         [0039]    In a preferred embodiment, receiver  500  is made of a durable plastic, but can be made of other materials such as a durable metal or metal alloy. 
         [0040]    Spring damper assembly  400  is slidingly engaged with inside surface  507  of receiver  500  and removably supported by receiver end  510 . Spring damper assembly  400  comprises cylinder  420  having proximal end  401 , distal end  402 , and outside surface  403 . Flexible tip  404  has a generally convex shape and is removably attached to distal end  402  by frictional engagement with mounting post  413  and distal end  402 . Guide flanges  405 ,  406 , and  407  are attached to outside surface  403  at proximal end  401  and slidingly engage with slots  505 ,  508 , and  510  in flange  501  of receiver  500 . Piston rod  408  is slidingly engaged with proximal end  401  and is connected to a piston. The piston is slidingly engaged with an inside surface of cylinder  420 . The inside surface of cylinder  420  forms a fluid chamber, which contains a damper fluid. Piston rod  408  is concentrically aligned with a piston guide in proximal end  401 . The piston guide forms a seal with piston rod  408  to prevent the damper fluid from escaping cylinder  420 . The piston has at least one fluid channel through which the damper fluid can pass. A spring is positioned between the piston and distal end  402  and urges against the piston and distal end  402 . 
         [0041]    In a preferred embodiment, cylinder  420  is formed of extruded plastic or other suitable materials for lightweight durability and affordability. Piston rod  408  is made of aluminum, but can be made of other metals or metal alloys with similar lightweight and strength properties. The piston is made of aluminum or can be made of other durable, lightweight materials known in the art. Flexible tip  404  may be made of plastic, rubber, or a dense energy absorbing foam rubber. The damper fluid is a mineral oil, but other fluids known in the art may be suitably employed. The damper fluid fills approximately 80% of the volume of the inside of cylinder  420  less the volumes of piston rod  408 , the piston, and the spring. Other suitable fluid capacities known in the art may be employed as well. The spring is made of a durable metal with a spring constant in a range of approximately 10 lbs./inch to 20 lbs./inch. 
         [0042]    Referring to  FIG. 3A , attachment  10  is attached to hinge  600  with fastener hook  207  hooked onto the side of a hole in hinge  600 . Hinge  600  has door portion  650 , hinge cup  651 , and hinge plate  652 . Housing portion  300  and spring damper assembly  400  are positioned at an off-set angle with respect to connector portion  200 . Support abutments  212 ,  213 ,  216 , and  214  and fastening hook  207  are angled to facilitate the off-set position of housing portion  300  and spring damper assembly  400  by extending generally perpendicularly from the off-set position of housing portion  300  and spring damper assembly  400 . Connector portion  200  is positioned along axis  950  and housing portion  300  and spring damper assembly  400  are positioned along axis  951 . Axis  950  and axis  951  are separated by off-set angle ω. 
         [0043]    In a preferred embodiment, off-set angle ω is in a range of about 1° to about 20°. 
       EXAMPLE 1 
       [0044]    Referring to  FIG. 3B , when hinge plate  652  impacts prior art damper  5003 , the forces exerted on prior art damper  5003  are defined as follows:
       (1) F 1x =F 1  cos β; where F 1  is the force of the door exerted by hinge plate  652  and β is the angle between F 1  and the x-axis.   (2) F 1x d 1 =m 1 ; where m 1  is the moment exerted on the piston inside prior art damper  5003  to counteract F 1x  and d 1  is the distance the center of the piston is located from the x-axis at impact, and   (3) F 1x d 1 =F 2 d 2 +F 3 d 3 ; where d 2  and d 3  are the distances the edges of the piston are from the center of the piston and F 2  and F 3  are the forces exerted on the piston. F 1y  is negligible because prior art damper  5003  moves along the y-axis to absorb F 1y .       
 
         [0048]    Referring to  FIG. 3C , when hinge plate  652  impacts spring damper assembly  400  of the preferred embodiment, the forces exerted on spring damper assembly  400  and the results are as follows: 
         [0000]      F′ 1x =F 1  cos β′;
 
         [0000]    
       
         
           
             
               F 
               1 
             
             = 
             
               
                 F 
                 
                   1 
                    
                   x 
                 
                 ′ 
               
               
                 cos 
                  
                 
                     
                 
                  
                 
                   β 
                   ′ 
                 
               
             
           
         
       
     
         [0000]    and from 
         [0000]    
       
         
           
             
               
                 F 
                 1 
               
               = 
               
                 
                   F 
                   
                     1 
                      
                     x 
                   
                 
                 
                   cos 
                    
                   
                       
                   
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             , 
           
         
       
     
         [0000]    then; 
         [0000]    
       
         
           
             
               
                 
                   F 
                   
                     1 
                      
                     x 
                   
                 
                 
                   cos 
                    
                   
                       
                   
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               = 
               
                 
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                   ′ 
                 
                 
                   cos 
                    
                   
                       
                   
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                     β 
                     ′ 
                   
                 
               
             
             ; 
           
         
       
     
         [0000]    where β′=β+ω, ω is the off-set angle of the preferred embodiment, with β=45°, ω=10°; 
         [0000]    
       
         
           
             
               
                 cos 
                  
                 
                     
                 
                  
                 
                   ( 
                   
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                     ω 
                   
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                 .573 
                 .707 
               
               ≈ 
               
                 19 
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                 % 
               
             
           
         
       
     
         [0000]    reduction from F 1x  to F′ 1x ; therefore a 9.5% reduction from F 2  and F 3  to F′ 2  and F′ 3 , respectively; thereby reducing m 1  to m′ 1 . 
         [0049]    The example shows that the force resisted by the cylinder F′ 1x  is reduced, thereby reducing wear on the cylinder and increasing the useful life of the damping mechanism. 
         [0050]    Referring to  FIGS. 4A ,  4 B, and  4 C in use, attachment  10  is attached to hinge  600 , which is fastened to cabinet  700 . Attachment  10  is clipped onto hinge  600  with fastener hook  207 . To detach attachment  10 , attachment  10  is pulled from hinge  600 . Hinge  600  has door portion  650 , which is attached to door  750 . Door portion  650  and door  750  begin at open position  806  and travel through angle α with a closing speed sufficient to propel door portion  650  and door  750  to closed position  808  to ensure door  750  will close and not remain open after contact with spring damper assembly  400 . Angle α is approximately 120°. Spring damper assembly  400  is in ready position  809 . 
         [0051]    At impact position  807 , door portion  650  applies force  903  on spring damper assembly  400 . The flexibility of flexible tip  404  and the contents of cylinder  420  of spring damper assembly  400  urge to absorb force  903 . As door  750  and door portion  650  continue to swing closed through angle λ, piston rod  408  remains stationary relative to housing portion  300  and receiver  500 . Angle λ is approximately 30°. Spring damper assembly  400  slides through housing portion  300  against the bias of the spring and the piston attached to piston rod  408 , moving through the inside of cylinder  420  to closed position  808 . The damper fluid moves through the fluid channels in the piston to dampen force  903 . 
         [0052]    Referring to  FIG. 5  in another embodiment, attachment  1000  comprises body  1100 , spring damper assembly  400 , and adjustment knob  1500 . Body  1100  has connector portion  1200  and housing portion  1300 . Connector portion  1200  has base  1201 , attached to housing portion  1300 . Connector portion  1200  extends generally radially from housing portion  1300 . Base  1201  is attached to sides  1202  and  1203 . Base  1201  has ends  1204  and  1205 . Side  1202 , base  1201 , and side  1203  form a generally rectangular channel. End  1204  includes securing hook  1206 . Base  1201  has adjustment hole  1207  and cam locking mechanism  1208 . Cam locking mechanism  1208  further includes hole  1209  to receive fastener  1210 . Fastener  1210  has cam pin  1227 . Fastener  1210  is situated through hole  1209  and hole  1225  in cam lock  1211 . Cam pin  1227  is secured to cam cap  1220  by a suitable welding means known in the art. Adjustment hole  1207  has sufficient dimensions to allow a user to adjust a pre-mounted hinge to which attachment  1000  is attached. 
         [0053]    Housing portion  1300  has receiver end  1301 , spring damper end  1302 , outside surface  1303 , and inside surface  1304 . Receiver end  1301  has hole  1308 . Hole  1308  has internal threads  1309 , which are adapted to receive adjustment knob  1500 . Spring damper end  1302  has hole  1306 . Hole  1306  has slot  1305  to slidingly receive guide flange  405  on spring damper assembly  400 . Gap  1307  is positioned axially along housing portion  1300  to conserve weight and material costs. 
         [0054]    In a preferred embodiment, body  1100  is made of a zinc die cast, but can be made of a suitable plastic, a suitable metal, or a suitable metal alloy. Fastener  1210  can be a multitude of fasteners known in the art. Cam lock  1211  and cam cap  1220  are made of a durable metal, but can be made of a durable plastic or metal alloy. 
         [0055]    Adjustment knob  1500  has receiving hole  1505  to removably support piston rod  408  of spring damper assembly  400 . Adjustment knob  1500  further has a set of external threads that match internal threads  1309  in hole  1308  of housing portion  1300 . 
         [0056]    In a preferred embodiment, adjustment knob  1500  is made of a durable plastic, but can be made of a durable metal or metal alloy. 
         [0057]    Spring damper assembly  400  is slidingly engaged with inside surface  1304  of housing portion  1300  and removably supported by receiving hole  1505  of adjustment knob  1500 . Spring damper assembly  400  comprises cylinder  420  having proximal end  401 , distal end  402 , and outside surface  403 . Flexible tip  404  has a generally convex shape and is removably attached to distal end  402  by frictional engagement with mounting post  413  and distal end  402 . Guide flange  405  is attached to outside surface  403  at proximal end  401  and is slidingly engaged with slot  1305  of housing portion  1300 . Piston rod  408  is slidingly engaged with proximal end  401  and is connected to a piston. The piston is slidingly engaged with the inside surface of cylinder  420 . The inside surface of cylinder  420  forms a fluid chamber, which contains a damper fluid. Piston rod  408  is concentrically aligned with a piston guide in proximal end  401 . The piston guide forms a seal with piston rod  408  to prevent the damper fluid from escaping cylinder  420 . The piston has at least one fluid channel through which the damper fluid can pass. A spring is positioned between the piston and distal end  402  and urges against the piston and distal end  402 . 
         [0058]    In a preferred embodiment, cylinder  420  is formed of extruded plastic or other suitable materials for lightweight durability and affordability. Piston rod  408  is made of aluminum, but can be made of other metals or metal alloys with similar lightweight and strength properties. The piston is made of aluminum or can be made of other durable, lightweight materials known in the art. Flexible tip  404  may be made of plastic, rubber, or a dense energy absorbing foam rubber. The damper fluid is a mineral oil, but other fluids known in the art may be suitably employed. The damper fluid fills approximately 80% of the volume of the inside of cylinder  420  less the volumes of piston rod  408 , the piston, and the spring. Other suitable fluid capacities known in the art may be employed as well. The spring is made of a durable metal with a spring constant in a range of approximately 10 lbs./inch to 20 lbs./inch. 
         [0059]    Referring to  FIG. 6 , cam locking mechanism  1208  includes riser  1213 , which is attached to base  1201 . Channel  1214  is connected onto riser  1213  and is generally “U”-shaped to slidingly receive cam lock  1211 . Cam lock  1211  is seated into inside surface  1215  of channel  1214 . Fastener  1210  has shaft  1228  and cam pin  1227 . Cam pin  1227  is attached to the end of shaft  1228  in an off-center position. Shaft  1228  is situated through hole  1209  and cam pin  1227  is situated through hole  1225  of cam lock  1211  to attach to cam cap  1220  by insertion into hole  1230  and welded into place by a welding means known in the art. Cam cap  1220  is then slidingly secured onto surface  1226  of cam lock  1211 . 
         [0060]    Referring to  FIGS. 5 and 6 , in use, soft close hinge attachment  1000  is mounted onto a pre-mounted hinge by securing hook  1206  and cam locking mechanism  1208 . Cam locking mechanism  1208  secures soft close hinge attachment  1000  to a pre-mounted hinge by turning fastener  1210  in direction  2001 . The rotation of fastener  1210  and the off-center position of cam pin  1227  advances cam lock  1211  in direction  2002  extending partially over adjustment hole  1207 ; thereby coupling soft close hinge attachment  1000  to a pre-mounted hinge. Adjustment knob  1500  is threadingly engaged with receiver end  1301 . Spring damper assembly  400  slides into hole  1306  at spring damper end  1302 . Guide flange  405  slides into slot  1305  to allow piston rod  408  to be removably supported in receiving hole  1505 . 
         [0061]    To detach attachment  1000  from a pre-mounted hinge, fastener  1210  is rotated in direction  2000 , thereby retreating cam lock  1211  in direction  2003  to re-seat cam lock  1211  on riser  1213 . Attachment  1000  is then pulled from the pre-mounted hinge. 
         [0062]    The damping functionality is adjusted by turning adjustment knob  1500  in direction  1900  or in direction  1901 . Advancing adjustment knob  1500  further axially into housing portion  1300  in direction  1902  at receiver end  1301  results in increasing the compressive strength of spring damper assembly  400  because spring damper assembly  400  extends further axially away from housing portion  1300  at spring damper end  1302  and catches the swinging door earlier in its swing path. 
         [0063]    Retreating adjustment knob  1500  out of housing portion  1300  in direction  1903  at receiver end  1301  results in decreasing the compressive strength of spring damper assembly  400  because the swinging door will meet spring damper assembly  400  further along in its swing path. 
         [0064]    Referring to  FIGS. 7A ,  7 B, and  7 C, in use, attachment  1000  is attached to hinge  1600  with securing hook  1206  and cam locking mechanism  1208 , which is fastened to cabinet  1700 . Hinge  1600  has door portion  1650 , which is attached to door  1750 . Door portion  1650  and door  1750  begin at open position  1806  and travel through angle θ with a closing speed sufficient to propel door portion  1650  and door  1750  to closed position  1808  to ensure door  1750  will close and not remain open after contact with spring damper assembly  400 . Angle θ is approximately 120°. Spring damper assembly  400  is in ready position  1809 . 
         [0065]    At impact position  1807 , door portion  1650  applies force  1903  on spring damper assembly  400 . The flexibility of flexible tip  404  and the contents of cylinder  420  of spring damper assembly  400  urge to absorb force  1903 . As door  1750  and door portion  1650  continue to swing closed through angle γ, piston rod  408  remains stationary relative to housing portion  1300  and adjustment knob  1500 . Angle γ is approximately 30°. Spring damper assembly  400  slides through housing portion  1300  against the bias of the spring and the piston attached to piston rod  408 , moving through the fluid chamber to closed position  1808 . The damper fluid moves through the at least one fluid channel to dampen force  1903 . 
         [0066]    It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.