Cable tensioning system, mounting plate assembly, retraction cam, damper system and method for operating a system

Abstract

Embodiments provides a cable tensioning system comprising a mounting plate assembly with a mounting plate and a retraction cam mounted to the mounting plate and configured to pivot about a primary axis, wherein the retraction cam comprises a cam body and a spur body having a cable sheave groove, wherein the mounting plate assembly is fixedly secured to a mounting fixture of a leg rest of a seat, and wherein the cable sheave groove is configured to receive a cable fixed to extension frame of the leg rest, the extension frame being movable relative to the mounting fixture.

What is claimed is: 
     
         1 . A cable tensioning system comprising:
 a mounting plate assembly comprising a mounting plate; and   a retraction cam mounted to the mounting plate and configured to pivot about a primary axis,   wherein the retraction cam comprises a cam body and a spur body having a cable sheave groove,   wherein the mounting plate assembly is fixedly secured to a mounting fixture of a leg rest of a seat, and   wherein the cable sheave groove is configured to receive a cable fixed to an extension frame of the leg rest, the extension frame being movable relative to the mounting fixture.   
     
     
         2 . The cable tensioning system of  claim 1 , further comprising:
 a torsion spring having a first leg secured to the cam body and a second leg interacting with a static catch arranged on the mounting plate; and   an extension spring coupled between the cam body and the spur body,   wherein the spur body is configured to pivot relative to the cam body to increase an effective arclength of the cable sheave groove when slack is introduced into the cable.   
     
     
         3 . The cable tensioning system of  claim 1 , wherein the spur body is configured to pivot up to 45 degrees relative to the cam body. 
     
     
         4 . The cable tensioning system of  claim 1 , further comprising a damper system comprising damper plate assembly and a damper housing assembly rotatably fixing the damper plate assembly and to the extension frame, wherein the cam body is in contact with the damper system. 
     
     
         5 . The cable tensioning system of  claim 4 , wherein the retraction cam comprises a damper groove profile attached to a main surface of the retraction cam, wherein the mounting plate assembly comprises a swing arm assembly configured to pivot relative to the mounting plate, wherein the damper plate assembly comprises a damper plate, and wherein a rotation of the retraction cam is configured to move the swing arm assembly so that the swing arm assembly moves the damper plate when the extension frame of the leg rest is manually retracted. 
     
     
         6 . The cable tensioning system of  claim 5 , further comprising a support plate rotatably fixing the swing arm assembly to the mounting plate. 
     
     
         7 . The cable tensioning system of  claim 6 , wherein the swing arm assembly comprises a swing arm shaft, a groove follower and a lever arm, wherein the swing arm assembly is arranged so that the groove follower is sandwiched between the support plate and the mounting plate, so that the lever arm is arranged at a side of the support plate opposite to a side where the groove follower is located, and so that the swing arm assembly is pivotable about the swing arm shaft. 
     
     
         8 . A leg rest system comprising:
 the cable tensioning system of  claim 1 ;   the extension frame;   the mounting fixture;   the cable coupled between the extension frame and the mounting fixture and arranged in the cable sheave groove; and   wherein the cable tensioning system is configured to maintain a tension in the cable during operation of the leg rest system.   
     
     
         9 . A retraction cam comprising:
 a cam body having a pivot axle;   a spur body arranged on the cam body and pivotably guided by the cam body; and   a tensioning spring secured to the cam body and the spur body and allowing the spur body to pivot on the cam body,   wherein the pivot axle of the retraction cam is pivotable about a mounting point of an external device.   
     
     
         10 . The retraction cam of  claim 9 , wherein the cam body comprises a rotation stabilization flange, wherein the spur body comprises a rotation stabilization flange channel formed by a post and a rotation bearing, and wherein the rotation stabilization flange is configured to interact with the rotation stabilization flange channel. 
     
     
         11 . The retraction cam of  claim 10 , wherein the rotation bearing is removably secured to and comprises a different material than the spur body. 
     
     
         12 . The retraction cam of  claim 10 , wherein the cam body comprises an intermediate bearing, wherein the spur body comprises an intermediate bearing channel, and wherein the intermediate bearing is configured to interact with the intermediate bearing channel. 
     
     
         13 . The retraction cam of  claim 12 , wherein the intermediate bearing is a plate, which is removably secured to and which comprises a different material than the cam body. 
     
     
         14 . The retraction cam of  claim 9 , wherein the spur body is embodied as a cable sheave configured to receive one end of a cable. 
     
     
         15 . The retraction cam of  claim 9 , wherein the cam body and the spur body are configured to pivot against each other, and wherein, when the spur body, under an influence of the tensioning spring, moves away from the cam body slack decreases. 
     
     
         16 . A mounting plate assembly for a leg rest system, the mounting plate assembly comprising:
 a mounting plate;   a support plate coupled to the mounting plate;   a swing arm assembly mounted between the mounting plate and the support plate, the swing arm assembly comprising:
 a swing arm shaft; 
 a groove follower mounted to the swing arm shaft; and 
 a lever arm mounted to the swing arm shaft; 
   a first bushing installed in the support plate configured for guiding the swing arm shaft; and   a second bushing installed in the mounting plate configured for guiding the swing arm shaft.   
     
     
         17 . The mounting plate assembly of  claim 16 , further comprising a static torsion spring catch arranged on a side of the mounting plate opposite to where the support plate is arranged. 
     
     
         18 . The mounting plate assembly of  claim 16 , wherein the swing arm assembly is arranged so that the groove follower is sandwiched between the support plate and the mounting plate, so that the lever arm is arranged at a side of the support plate opposite to a side where the groove follower is located, and so that the swing arm assembly is pivotable about the swing arm shaft. 
     
     
         19 . A damper system comprising:
 a damper housing assembly;   a rotational damper plate assembly comprising a damper plate having a hook feature configured to engage a lever arm of a swing arm assembly and a ramp surface configured to guide the lever arm, the hook feature and the ramp surface being formed on a connection surface between a first main surface and a second main surface of the damper plate; and   a torsion spring arranged between the damper housing assembly and the rotational damper plate assembly.   
     
     
         20 . The damper system of  claim 19 ,
 wherein the damper housing assembly comprises a shielded cavity housing the torsion spring, and   wherein the rotational damper plate assembly comprises a cylindrical flange extension on which the torsion spring is arranged.   
     
     
         21 . The damper system of  claim 19 , wherein the damper housing assembly is configured to secure the rotational damper plate assembly and the damper mounting housing assembly to an extension frame of a leg rest so that the damper plate assembly is sandwiched between the damper housing assembly and the extension frame. 
     
     
         22 . The damper system of  claim 19 , wherein the hook feature is configured to provide a force to maintain a leg rest in its deployed position, and wherein the ramp surface is configured to allow reengagement between the lever arm and the hook feature when the leg rest of an extension frame is manually retracted with a force greater than a resistance force of the damper system. 
     
     
         23 . A method for operating a system comprising a retraction cam and a mounting plate assembly, wherein the retraction cam is rotatably fixed to a mounting plate of the mounting plate assembly and comprises a cam body and a spur body, and wherein one end of a cable is fixed to the retraction cam and another end is fixed to an extension frame of a leg rest of a seat, the method comprising:
 retracting the leg rest from a deployed position to a stowed position;   while retracting, applying, by a torsion spring, a force to the retraction cam thereby pivoting the retraction cam; and   while retracting, applying, by a tensioning spring, a force to the spur body thereby pivoting the spur body against the cam body.   
     
     
         24 . The method of  claim 23 , further comprising:
 guiding, by a groove profile arranged at a second side surface of the retraction cam, a groove follower located at the mounting plate assembly, thereby pivoting a lever arm connected to the groove follower; and   clearing, by the lever arm, a hook feature of a damper plate.