Patent Publication Number: US-7585018-B2

Title: Wall proximity reclining chair with in-line linkage mechanism

Description:
FIELD 
     The present disclosure relates to furniture member operating mechanisms and to a device and method for operating a reclining furniture member assembly. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
     Conventionally, reclining articles of furniture (i.e., chairs, sofas, loveseats, and the like) require a mechanism to bias a leg rest assembly in the extended and stowed positions. Known mechanisms commonly include a large number of moving parts that tends to increase the manufacturing time and costs associated with the furniture. 
     Most reclining rocking chairs include an upholstered chair frame supported from a stationary base assembly in a manner permitting the chair frame to “rock” freely with respect to the base assembly. In order to provide enhanced comfort and convenience, many rocking chairs also include a “reclinable” seat assembly and/or an “extensible” leg rest assembly. For example, combination platform rocking/reclining chairs, as disclosed in Applicant&#39;s U.S. Pat. Nos. 3,096,121 and 4,179,157, permit reclining movement of the seat assembly and actuation of the leg rest assembly independently of the conventional “rocking” action. The leg rest assembly is operably coupled to a drive mechanism to permit the seat occupant to selectively move the leg rest assembly between its normally retracted (i.e., “stowed”) and elevated (i.e., “extended”) positions. The drive mechanism is manually-operated and includes a handle which, when rotated by the seat occupant, causes concurrent rotation of a drive rod for extending or retracting the leg rest assembly. Disadvantages of known mechanisms for providing these functions include a large quantity of parts and their requirement of one or several spring biasing elements to permit retraction of the various chair components from their extended positions. 
     As an additional comfort feature, a latching mechanism may also be provided for releasably retaining the chair frame in one or more rearwardly rocked or “tilted” positions on the base assembly following extension of the leg rest assembly towards its extended position. In this manner, normal “rocking” action of the rocking chair is inhibited until the leg rest assembly is returned to its normally “stowed” position. Known leg rest mechanisms also provide multiple functional positions, which can be reached using a detente mechanism, which temporarily holds the leg rest at each successive position. A disadvantage of this mechanism design results as the furniture member rocks backward when the leg rest is moved between the successive positions. An improved mechanism is therefore desirable to eliminate the above disadvantages. 
     SUMMARY 
     According to several embodiments of the present disclosure, a furniture member actuation mechanism includes opposed first and second side plates, having first and second polymeric motion inserts, the first motion insert connected to the first side plate and the second motion insert connected to the second side plate. Each motion insert has an elongated slot. A first pin is inserted through the elongated slot of the first motion insert. A second pin is inserted through the elongated slot of the second motion insert. First and second seat back support elements are included, the first element rotatably coupled to the first side plate and rotatably linked to the first pin and the second element rotatably coupled to the second side plate and rotatably linked to the second pin. A rearward force applied by an occupant to both the first and second seat back support elements is operable to create a rearward rotation of the seat back support elements with the first and second pins slidable within the elongated slots, and a weight of the occupant when the rearward force is removed is operable to return the seat back support elements to a pre-rotation position. 
     According to other embodiments, a drive rod is rotatably disposed through both the first and second side plates. The first and second leg rest support arms are each connected by a pantograph linkage set to the drive rod. A cam is connected to the second side plate. Rotation of the drive rod is operable to rotate the first and second leg rest support arms between a stowed and an extended position. The cam is rotatable to adjust an occupant load applied to the leg rest support arms to return the leg rest support arms from the extended position to the stowed position. 
     According to still further embodiments, a substantially rectangular shaped frame includes first and second lateral members and first and second transverse members coupled to the first and second lateral members. A first forward oriented link member and a first rearward oriented link member both connect the first side plate to the first lateral element. Second forward and rearward oriented link members both connect the second side plate to the second lateral element. A first cross brace connects the first and second forward oriented link members. A second cross brace connects the first and second rearward oriented link members. 
     According to yet still further embodiments, a furniture member actuation mechanism includes a plate connected by first and second links to a frame. First and second polymeric motion inserts are connected to the plate, each of the motion inserts having an elongated slot. A seat back support element is rotatably connected to the plate. A first pin is slidably received in the elongated slot of the first motion insert and rotatably linked to both the seat back support element and the first link. A leg rest support arm is connected by a pantograph linkage set to the plate. A second pin is connected by a cross link to the first pin and rotatably coupled to the second link, the second pin being slidable within the elongated slot of the second motion insert when the pantograph linkage set operates between each of a retracted and an extended position. 
     According to still further embodiments, a drive rod is rotatably connected between the first and second side plates. A lock link is coupled to the drive rod proximate the first side plate. An over-center toggle is rotatably connected to the lock link. A plurality of pantograph linkage sets are connected between each of the first and second side plates and the leg rest. The drive rod is induced to rotate by release of the over-center toggle and rotation of the lock link separately controls a leg rest position. 
     According to yet still further embodiments, a stop drive link controls the leverage of the linkage mechanism and provides adjustment for the support of an extended footrest. Adjustment is controlled by varying the stop position of the linkage mechanism. The stop drive link also provides a mechanism that transfers an occupant&#39;s weight into rotational torque of the drive rod by force transmittal from the furniture member base to the drive rod and a close-to-center three pivot configuration of the mechanism. 
     Further areas of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating several embodiments of the present disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
         FIG. 1  is a front perspective view of a furniture member having an in-line linkage mechanism of the present disclosure; 
         FIG. 2  is a front perspective view of the furniture member of  FIG. 1  having a leg rest assembly shown in an extended position; 
         FIG. 3  is a rear perspective view of the actuation mechanism of the present disclosure; 
         FIG. 4  is a side elevational view of the actuation mechanism of  FIG. 3 ; 
         FIG. 5  is a side elevational view of the actuation mechanism of  FIG. 3  and opposite to the view of  FIG. 4 ; 
         FIG. 6  is a rear perspective view of the actuation mechanism of the present disclosure shown in an extended position; 
         FIG. 7  is a side elevational view of the actuation mechanism of  FIG. 6 ; 
         FIG. 8  is a top plan view of the actuation mechanism of  FIG. 3 ; 
         FIG. 9  is a perspective view of a leg rest lock link of the present disclosure; 
         FIG. 10  is a top plan view of the lock link of  FIG. 9 ; 
         FIG. 11  is a front elevational view of the lock link of  FIG. 10 ; 
         FIG. 12  is a front elevational view of an over-center toggle of the present disclosure; 
         FIG. 13  is a top plan view of the over-center toggle of  FIG. 12 ; 
         FIG. 14  is a perspective view of a trip lever of the present disclosure; 
         FIG. 15  is a front elevational view of the trip lever of  FIG. 14 ; 
         FIG. 16  is a side elevational view of the trip lever of  FIG. 15 ; 
         FIG. 17  is a top plan view of the trip lever of  FIG. 15 ; 
         FIG. 18  is a rear elevational view of the trip lever of  FIG. 14 ; 
         FIG. 19  is a perspective view of a stop drive element of the present disclosure; 
         FIG. 20  is a side elevational view of the stop drive element of  FIG. 19 ; 
         FIG. 21  is a cross sectional view taken at section  21 - 21  of  FIG. 20 ; 
         FIG. 22  is a cross sectional view taken at section  22 - 22  of  FIG. 20 ; 
         FIG. 23  is a perspective view of a cam of the present disclosure; 
         FIG. 24  is a front elevational view of the cam of  FIG. 23 ; 
         FIG. 25  is a top plan view of the cam of  FIG. 24 ; 
         FIG. 26  is a front elevational view of further embodiments of a cam of the present disclosure; 
         FIG. 27  is a cross sectional view taken at section  27 - 27  of  FIG. 26 ; 
         FIG. 28  is a perspective partial assembly view of a cross brace and support arm of the present disclosure; 
         FIG. 29  is a top plan view of an assembled cross brace and support arm of  FIG. 28 ; 
         FIG. 30  is a front perspective view of a furniture member similar to  FIG. 1  showing a lever arm for actuating the furniture member; and 
         FIG. 31  is a front perspective view of the furniture member of  FIG. 31  showing a leg rest assembly in an extended position. 
     
    
    
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
     With particular reference now to the drawings, in accordance with the present disclosure and referring generally to  FIG. 1 , a furniture member  10  depicted as a reclining chair includes first and second sides  12 ,  14  and an occupant seat back  16  covered with a seat back cushion assembly  18 . An occupant support member  20  is suspended between the first and second sides  12 ,  14  and a padded leg support  22  is also provided. A padded, extendable leg rest  24  is also provided. First and second arm rest pads  26 ,  28  can be used to cover the upper surfaces of the first and second sides  12 ,  14  respectively. An occupant&#39;s weight generally centered on support member  20  is normally operable to maintain seat back  16  in an upright position. When leg rest  24  is in the stowed position shown, seat back  16  can “pre-recline” or rotate about a seat back arc of rotation  29  independent of the first and second sides  12 ,  14 , support member  20  or leg rest  24  when the occupant leans backward against seat back  16 . Seat back  16  can also be returned to the upright position shown and opposite to seat back arc of rotation  29  by the weight of the occupant when the occupant leans forward. In several embodiments, furniture member  10  can further rotate about a furniture member arc of rotation  30 . In the embodiment shown, furniture member  10  is a chair however the present teachings are not limited to chairs. Furniture member  10  can be any of a plurality of furniture members, including, but not limited to single or multiple person furniture members, non-rocking recliners, sofas, sectional members and/or loveseats. In several embodiments, furniture member  10  includes a release latch  31  to manually release the leg rest  24  from the stowed position shown. 
     Referring generally now to  FIG. 2 , release latch  31  is connected to an actuation mechanism  32  and when release latch  31  is manually actuated, actuation mechanism  32 , directs the repositioning of leg rest  24  from the stowed position (shown in  FIG. 1 ) to an extended position by motion of the leg rest  24  about an extension arc  33 . It will be apparent that manual rotation of leg rest  24  in an opposite direction from extension arc  33  will return the leg rest  24  to the stowed position. Actuation mechanism  32  supports leg rest  24 . More specifically, actuation mechanism  32  includes first and second pantograph linkage sets  34 ,  35  (second pantograph linkage sets  35  are not visible in this view) which are linked to leg rest  24  using first and second leg rest support arms  36 ,  37  (only first leg rest support arm  36  is visible in this view). 
     Referring generally now to  FIG. 3 , the functional and structural aspects of actuation mechanism  32  for use in single or multi-person furniture members  10  is shown. For purposes of clarity,  FIG. 3  shows the various pre-assembled frame components with their upholstery, padding, etc. removed to better illustrate the interdependency of the frame components&#39; construction which can be rapidly and rigidly assembled in a relative easy and efficient manner. Therefore, all of the frame components can be individually fabricated or sub-assembled to include the requisite brackets, springs, padding and upholstery on an “off-line” batch-type basis. Thereafter, the various pre-assembled and upholstered furniture components are assembled for totally integrating actuation mechanism  32  therein. 
     Actuation mechanism  32  provides multiple features which will each be separately described, including: 1) a simplified, rigid frame structure; 2) an occupant induced, gravity or weight return “pre-reclining” function partially described above which does not rely on a spring biasing device, which uses slotted motion inserts and pins that replace common spring/link devices to provide for the “pre-reclining” function; 3) an “over-center” locking link feature which biases the leg rest  24  in the stowed or extended positions without the biasing force of spring elements; 4) a stop drive link which rotates independent of the locking link to provide an additional range of leg rest motion and 5) a cam system that permits manual pre-adjustment of the load that leg rest  24  can support in the extended position. 
     As generally used herein, the terms front or forward and right hand or left hand refer to the direction an occupant of the furniture member  10  faces when seated or with respect to the occupant&#39;s sides when the occupant is seated. The terms rear or rearward refer to a direction opposite to the front or forward direction. The rigid frame structure supporting actuation mechanism  32  includes front and rear cross frame members  38 ,  40  which in some embodiments can be created from bent or extruded angle elements, of metal such as steel material or composite materials. First and second lateral frame members  42 ,  44  which in some embodiments are also created from angle elements are connected at opposed ends to each of the front and rear cross frame members  38 ,  40  by welding or by using connectors such as threaded fasteners or rivets. Occupant loads at the front portion of furniture member  10  are transferred to first and second lateral frame members  42 ,  44  by first and second front support arms  46 ,  48  rotatably pinned or riveted to first or second lateral frame members  42 ,  44 . A front cross brace  50  is connected between each of the first and second front support arms  46 ,  48  by a single fastener at each end of the brace. Similarly, occupant loads at the rear portion of the furniture member  10  are transferred to first and second lateral frame members  42 ,  44  by first and second rear support arms  52 ,  54  pinned or riveted to first or second lateral frame members  42 ,  44 . A rear cross brace  56  is connected between each of first and second rear support arms  52 ,  54  also by a single fastener at each end of the rear cross brace  56 . The frame structure can be of made in general of metal such as steel or aluminum, or of one or more polymeric or composite materials. The present disclosure is not limited by the material used for the frame components. 
     The occupant induced, gravity return “pre-reclining”function is provided by a combination of links and support members and the use of pins slidably retained in motion inserts. The term “motion insert”as used herein refers to a member such as an insert fixedly connected to structure which permits sliding motion of the pin or pins within elongated slots thereof and the further description of “forward or “rear”with respect to these components identifies their installed position with respect to each other and not to a limiting direction of motion permitted. Each of the first and second seat back support elements  62 ,  64  are rotatably coupled to the first and second side plates  58 ,  60 , respectively, and further rotatably coupled to one end of each of a first or second crescent-shaped actuation link  66 ,  67 . Opposed ends of the first and second actuation links  66 ,  67  are in turn rotatably coupled to either a first or second flanged link  68 ,  69 , respectively. Opposed ends of the first and second flanged links  68 ,  69  are rotatably coupled to first and second connecting links  70 ,  71 . Polymeric first and second rear motion inserts  72 ,  73  are connected to the first and second side plates  58 ,  60 . Opposite ends of the first and second connecting links  70 ,  71  are pinned using first and second rear motion pins  74 ,  74 ′ which are further inserted through elongated slots  75 ,  75 ′ of first and second rear motion inserts  72 ,  73 . First and second rear motion pins  74 ,  74 ′ are concomitantly inserted through receiving apertures of first and second cross links  76 ,  77  which connect upper ends of respective pairs of first front support arm  46  and first rear support arm  52 , or second front support arm  48  and second rear support arm  54 . 
     Full extension motion of furniture member  10  and leg rest  24  is controlled by a drive rod  78  which is rotatably supported by first and second side plates  58 ,  60  and connected at opposite ends to leg rest lock links  80 ,  81  and stop drive elements or links  82  which are themselves located proximate each of the first or second side plates  58 ,  60 . In some embodiments, drive rod  78  is square or rectangular in shape, and is received in a correspondingly shaped aperture of leg rest lock links  80 ,  81  (lock link  81  is not clearly visible in this view) and opposed stop drive links  82 . At an opposite end of leg rest lock link  80  from the connection of drive rod  78 , an over-center toggle  84  is rotatably connected. A drive link  85  is also co-rotatably connected with over-center toggle  84  to leg rest lock link  80 . An opposite end of drive link  85  is rotatably connected to one of the links of first pantograph linkage set  34 . A biasing element  86  which in some embodiments can be a coiled spring is connected between over-center toggle  84  and an aperture and a notch  88  formed in a bracket  90  integrally joined to first side plate  58  proximate a forward facing end of first side plate  58 . In several embodiments having release latch  31 , a trip lever  92  rotatably connected to first side plate  58  is released when release latch  31  is actuated. Rotation of trip lever  92  rotates leg rest lock link  80  to permit extension of leg rest  24  and first and second pantograph linkage sets  34 ,  35 . Trip lever  92  can be continuously biased in each of a retention position (retaining the stowed position of leg rest  24 ) and a release position (allowing the extension of leg rest  24 ) by a trip lever biasing element  94  such as a coiled spring, which is connected between trip lever  92  and a trip lever bracket  96 . Trip lever bracket  96 , similar to bracket  90 , can be an integral extension of first side plate  58 . When leg rest  24  is released from the stowed position, a manually adjustable 3-position detente cam  98  is provided to permit pre-determining a weight or load that leg rest  24  will support before leg rest  24  is induced to return from the extended position to the stowed position. 
     The stop drive links  82  rotate relative to the lock links  80 ,  81 . The additional rotation of stop drive links  82  allow for improved positioning of the first and second pantograph linkage sets  34 ,  35  to provide a linkage layout allowing a close-to-center three (3) pivot point function of the stop drive links  82  and actuation mechanism  32 . In several embodiments, the lock links  80 ,  81  rotate approximately 90 degrees and the stop drive links  82  rotate approximately 120 degrees. The additional 30 degrees of rotation of the stop drive links  82  provide for the 3 pivot point function of the first and second pantograph linkage sets  34 ,  35 , and permit the use of the 3-position detente cam  98  to temporarily “adjust” or fix the location of first and second pantograph linkage sets  34 ,  35  to the centered position. The lock links  80 ,  81  provide a journal bearing surface for the stop drive links  82  to rotate on. The external journal bearing of the lock links  80 ,  81  interact with the first and second side plates  58 ,  60  and also interact with the stop drive links  82 . The external journal of the lock links  80 ,  81  also provide a surface for a spring clip (not shown) that locates the stop drive links  82  relative to the first and second side plates  58 ,  60  and the drive rod  78 . An internal journal bearing of the stop drive links  82  provide a large bearing contact with the lock links  80 ,  81  to prevents distortion of the stop drive links  82  during force application. The interaction of the stop drive links  82  and the lock links  80 ,  81  permits an in-line layout of actuation mechanism  32  and reduces the amount of offset required for travel of the first and second pantograph linkage sets  34 ,  35  of actuation mechanism  32 . 
     Referring now to  FIG. 4 , the “pre-reclining” function operates as follows. First seat back support element  62  is rotatably coupled to first side plate  58  by a pin  100  and to one end of first actuation link  66  by a pin  102 . First actuation link  66  is rotatably coupled at a second end to first flanged link  68  by a pin  104 . First flanged link  68  is rotatably coupled to first side plate  58  with a pin  106  and at a second end to first connecting link  70  by a pin  108 . Pins  100 ,  102 ,  104 ,  106 , and  108  are fasteners such as, but not limited to spin rivets, bolts, or the like. Part numbers described above refer to the right hand side of actuation mechanism  32 , however it is noted similar parts on the left hand side (associated with second side plate  60 ) are connected and will move in a corresponding manner. 
     When an occupant seated on furniture member  10  leans backward (to the left as viewed in  FIG. 4 ), their weight or force is transferred through first seat back support element  62  and first actuation link  66  to first flanged link  68  and from first flanged link  68  to connecting link  70 . First flanged link  68  can rotate with respect to pin  106  about an arc of rotation  110 . As first flanged link  68  rotates about pin  106 , first rear motion pin  74 , which is connected to first connecting link  70 , slides within the elongated slot  75  of first rear motion insert  72 . Because first rear motion pin  74  is directly linked by first cross link  76  to a first forward motion pin  116 , as first rear motion pin  74  slides in elongated slot  75 , first forward motion pin  116  slides within an elongated slot  118  of a first forward motion insert  120  connected to first side plate  58 . The total travel distance of first flanged link  68  when first flanged link  68  contacts an extended portion of stop drive link  82  limits the total angular displacement of seat back  16  during pre-reclining motion. This angular displacement is approximately one third (33%) of the total rotation or angular displacement which seat back  16  can undergo. When the occupant leans forward from the pre-recline position of seat back  16 , the weight of the occupant is re-centered substantially forward (to the right as viewed in  FIG. 4 ) of pin  106  which reverses the rotation described above and returns first seat back support element  62  to the upright or non-reclined position. No biasing device or element is provided or required to assist the pre-recline function. First side plate  58  therefore can globally move forward and rearward with respect to first and second lateral frame members  42 ,  44 , first rear support arm  52  and first cross link  76 . 
     With further reference to  FIG. 4 , in the leg rest stowed position, a plane of action or centerline  112  of biasing element  86  is maintained above a centerline  114  of drive rod  78 . This over-center position of the biasing element  86  is maintained by over-center toggle  84  which can freely rotate at its connection point with leg rest lock link  80 . The biasing force of biasing element  86  is therefore functional to lock or maintain the stowed position of leg rest  24 . When trip lever  92  is rotated clockwise as viewed in  FIG. 4  by actuation of release latch  31 , trip lever  92  forces leg rest lock link  80  downward. When leg rest lock link  80  rotates far enough to reposition the centerline  112  of biasing element  86  below the centerline  114  of drive rod  78 , the biasing force of biasing element  86  acting through over-center toggle  84  rotates leg rest lock link  80  counterclockwise as viewed in  FIG. 4  with respect to drive rod  78 , allowing extension of leg rest  24 . As first and second pantograph linkage sets  34 ,  35  extend (to the right as viewed in  FIG. 4 ), first rear motion pin  74  and first forward motion pin  116  rotate within their corresponding elongated slots  75 ,  118 . 
     First rear motion insert  72  and first forward motion insert  120  can be provided of an elastomeric material such as a polyamide material. In some embodiments, a nylon  6 - 6  or an ultra high molecular weight material can be used. The polymeric material reduces sliding friction of first rear motion pin  74  or first forward motion pin  116 , which also eliminates the need to lubricate these sliding connections. 
     Referring generally to  FIG. 5 , components on a left hand or second side of actuation mechanism  32  include a second forward motion insert  122 , similar to first forward motion insert  120 . A second forward motion pin  124  is slidably received in an elongated slot  126  of second forward motion insert  122 , similar to first forward motion pin  116 . Second leg rest lock link  81  is not retained by a comparable trip lever to trip lever  92  on this side, and therefore no over-center toggle or biasing element is provided on this side. Second leg rest lock link  81  is connected at one end to drive rod  78  and at a second end is rotatably pinned to an extension link  128 . As drive rod  78  rotates, second leg rest lock link  81  operatively extends extension link  128  toward the left as viewed in  FIG. 5 . 
     As best seen in reference to  FIG. 6 , a fully extended leg rest and fully upright back support condition for actuation mechanism  32  is provided. In this position, first and second seat back support elements  62 ,  64  are positioned corresponding to a fully upright seat back  16 . First leg rest lock link  80  is rotated substantially 120° from its “locked” position when the actuation mechanism  32  is in the stowed position. Biasing element  86  provides an assisting biasing force to enable first and second pantograph linkages  34 ,  35  to fully extend. The stop drive links  82  in combination with biasing element  86  and cam  98  control the leverage support of the extended footrest by varying the fully extended position of the mechanism. The stop drive links  82  also transfer occupant weight into rotational torque of the drive rod  78  through force transmittal from the lateral frame member  44  providing a three pivot point layout whereby the pivot points are substantially in-line creating maximum support leverage for support of the occupant&#39;s legs and feet. Biasing element  94  provides a preload, or assist force to trip lever  92  such that when release latch  31  is actuated, biasing element  94  biases trip lever  92  in a generally counterclockwise direction as viewed in reference to  FIG. 6 . This biasing force returns trip lever  92  toward its normal position after rotating to release first leg rest lock link  80  to rotate away from the stowed position and into the extended position shown. 
     In several embodiments of the present disclosure, cam  98  can also include an extension element  132 . Extension element  132  is provided to manually grasp and rotate cam  98  between any of three detente positions which will be discussed in greater detail in reference to  FIGS. 23 through 25 . A leg support bar assembly  134  can also be provided with actuation mechanism  32 . Leg support bar assembly  134  is only supported to individual right hand and left hand members of first and second pantograph linkage sets  34 ,  35 . Because leg support bar assembly  134  is fastened to leg support  22 , as first and second pantograph linkage sets  34 ,  35  extend outwardly, leg support bar assembly  134  passively extends with leg rest  24 . No additional support or linkages are required for leg support bar assembly  134  because of the passive extension capability provided. 
     Referring now to  FIG. 7  and again to  FIG. 5 , a left hand or second side view of actuation mechanism  32  identifies the relationship between the rear and forward motion pins in their respective elongated slots. Second rear motion pin  74 ′ in the fully extended position of actuation mechanism  32  abuts a stop end  135  shown in  FIG. 5  of elongated slot  75 ′ .At the same time, second forward motion pin  124  also abuts a rearward facing stop end of elongated slot  126 . Second leg rest lock link  81  has rotated from the stowed position to the rotated extended position as drive rod  78  rotates. Extension link  128  is rotatably coupled to second leg rest lock link  81  using a pin  138 . In the fully extended position, a pin horizontal axis plane  136  defined through pin  138  is positioned below centerline  114  of drive rod  78 . To leave the leg rest fully extended position, seat back  16  must first be rotated back to its upright position reversing the pre-recline motion. Second rear motion pin  74 ′ and forward motion pin  124  slide in their respective elongated slots  75 ′ and  126  during this motion. When seat back  16  has returned completely to the upright position, first and second rear motion pins  74 ,  74 ′ and each of first forward motion pin  116  and second forward motion pin  124  are positioned within their respective elongated slots  75 ,  75 ′ ,  118  or  126  at opposite ends  137  from the pre-recline position. Once seat back  16  is returned to the upright position, the retention force of cam  98  is overcome by downwardly directing the leg weight of the occupant on leg rest  24 . This force initiates rotation of second leg rest lock link  81  back toward the stowed position. As first and second pantograph linkage sets  34 ,  35  return to the stowed position, first and second rear motion pins  74 ,  74 ′ and each of first forward motion pin  116  and second forward motion pin  124  translate within their respective elongated slots. 
     As best seen in reference to  FIG. 8 , each of the first and second rear motion pins  74 ,  74 ′, the first forward motion pin  116 , and the second forward motion pin  124  can be fastened using a retaining element  140  such as a wing nut. A biasing element  142  is positioned between the retaining element  140  and various link members joined by the motion pins. The purpose of biasing elements  142  is to provide adjustability to either increase or decrease the friction between the various members of actuation mechanism  32  as they extend or retract, which therefore also controls the mechanism speed and any assist effort required by the occupant. Each of the retaining elements  140  provides a retention force in either a first or second load directional path  144 ,  146 . A further benefit of retaining elements  140  occurs when the furniture members are shipped. It is common for furniture members  10  to be shipped having either a first or second side plate  58 ,  60  oriented in a downward facing direction. If retaining elements  140  are not used, and a hard connection or hard fastened joint is created, loads imparted on actuation mechanism  32  and furniture member  10  during shipment can damage the various members of actuation mechanism  32 . When biasing elements  142  are used, however, these elements act as shock absorbers to diminish the load applied in either of the first or second load directional paths  144  or  146 . 
     Referring now generally to  FIGS. 9 through 11 , each of first and second leg rest lock links  80 ,  81  include a lock link body  148  created from a polymeric material such as a polyamid material which provides low friction resistance and good wear resistance. Drive rod  78  is received in a receiving aperture  150  at a first end of lock link body  148 . At a second end of lock link body  148 , a toggle alignment aperture  152  is provided. A fastener such as a spin rivet (not shown) can be inserted through toggle alignment aperture  152  to join over-center toggle  84  to either first or second leg rest lock link  80 ,  81 . Also located at the first end of lock link body  148  is a reinforced portion  154  from which a cylinder end  156  extends substantially transverse to the lock link body  148 . Cylinder end  156  is sized to slidably fit and rotate within an aperture (not shown) provided in either first or second side plate  58 ,  60 . One or more retention device apertures  158  can be provided in cylinder end  156 . The purpose for retention device apertures  158  is to provide a locking device such as a lock wire or set screw to physically retain drive rod  78  within cylinder end  156  and reinforced portion  154 . Receiving aperture  150  is configured to suit the outer geometry of drive rod  78 . In the example shown in  FIG. 11 , drive rod  78  is substantially square in shape, therefore receiving aperture  150  is provided with four substantially equidistant length sides to engage the sides of drive rod  78 . One of the receiving walls or sides of receiving aperture  150  is oriented at an angle a with respect to a longitudinal axis of lock link body  148 . In several embodiments for the drive rod  78  having a substantially square shape, angle α is substantially equal to 45°. 
     Referring now generally to  FIGS. 12 and 13 , over-center toggle  84  includes a toggle body  160  having a through aperture  162  substantially centrally positioned within toggle body  160 . Toggle body  160  is substantially circular having a diameter “A”. Through aperture  162  has a diameter “B”. Diameter “B” is substantially equal to a diameter of the pin or fastener inserted in through aperture  162  and toggle alignment aperture  152  of first or second leg rest lock links  80 ,  81 . Over-center toggle  84  is also created from a polymeric material similar to the material used for first and second leg rest lock links  80 ,  81 . An arm  164  extends from toggle body  160  such that a total length “C” of over-center toggle  84  is provided. A biasing element receiving aperture  166  is positioned at a dimension “D” with respect to a centerline of through aperture  162 . Dimension “D” is predetermined to maintain sufficient wall thickness in arm  164  surrounding biasing element receiving aperture  166  to accommodate the biasing force provided by biasing element  86 . Toggle body  160  also has a total height “E”, and arm  164  has a total depth “F”. In several embodiments of the present disclosure, total length “C” is approximately 1.25 inches (3.17 cm), dimension “D” is approximately 0.56 inches (1.42 cm), height “E” is approximately 0.42 inches (1.07 cm), and depth “F” is approximately 0.21 inches (0.53 cm). 
     Referring now to  FIGS. 14 through 18  and with further reference to  FIGS. 4 and 6 , trip lever  92  can be constructed of a polymeric material similar to first and second leg rest lock links  80 ,  81  to reduce friction between operating parts and eliminate the need for lubrication. Trip lever  92  includes a trip lever body  170  having a head  172 . An engagement element  174  extends from a rear face of trip lever body  170  which engages first side plate  58 . Head  172  further includes a first rod  176  and a second rod  178  disposed at opposite sides of head  172 . A hook member  180  is also provided substantially centrally positioned between each of the first and second rods  176 ,  178 . First and second rods  176 ,  178  define a “cross-shape” which permits compounding the amount of travel of trip lever  92  about engagement element  174 , to activate the lock link  80  with limited stroke of a cable (not shown) connected between the release latch  31  and hook member  180 . First rod  176  is biased by biasing element  94  for rapid release of trip lever  92 . 
     Trip lever body  170  further includes a perimeter wall having a wall thickness “F”. Hook member  180  provides a cable engagement surface  182 . First rod  176  also includes a recessed portion  184  and second rod  178  includes a recessed portion  186 . Recessed portion  184  is provided to retain an end of biasing element  94  which is engaged with first rod  176 . Recessed portion  186  is provided to retain an end of biasing element (not shown) which is engaged with second rod  178  to normally bias trip lever  92  in contact with lock link  80 . Engagement element  174  extends from a rear side of trip lever  92 . A neck portion  188  provides an extension for engagement element  174  from the rear side which includes a length “G” which is dimensioned substantially equal to a thickness of first side plate  58 . First side plate  58  is therefore engaged between engagement element  174  and a combined plate engagement surface  190  allowing trip lever  92  to rotate with respect to first side plate  58 . 
     On the rearward facing side of trip lever  92  shown in  FIG. 18 , each of the first and second rods  176 ,  178  include an end face  192  and a raised surface  194 . Raised surface  194  is oriented at an angle P with respect to a longitudinal axis  196  of trip lever body  170 . Engagement element  174  is further configured as shown to include a center spherical portion  198  and each of a first and a second side spherical portion  200 ,  202 . A “compound engagement” is created as follows. Engagement element  174  is inserted into a correspondingly shaped aperture (not shown) in first side plate  58  which in several embodiments is oriented substantially 90° to the desired orientation of trip lever  92 . Trip lever  92  is then rotated approximately 90° about center spherical portion  198  until the extending portions of first and second side spherical portions  200 ,  202  engage first side plate  58 . First and second side spherical portions  200 ,  202  therefore provide a retention capability for trip lever  92 . A total width “H” is provided for engagement element  174  which is sized to be slidably received in the corresponding aperture of first side plate  58 . Because of the geometry of engagement element  174 , additional fasteners are not required to mount trip lever  92  to first side plate  58 . 
     Referring now to  FIGS. 19 through 22 , stop drive links  82  are also created from a polymeric material similar to first and second leg rest lock links  80 ,  81 . Stop drive links  82  include a body  204  having a perimeter raised rib  206  and a cylinder portion  208 . A through aperture  210  is centrally disposed through cylinder portion  208 . Through aperture  210  is sized to receive a cylindrical sleeve positioned at an end of drive rod  78 . First and second pin apertures  212 ,  214  are also provided with stop drive links  82 . First and second pin apertures  212 ,  214  provide for pinned connections to individual ones of the linkages associated with actuation mechanism  32 . As best seen in reference to  FIGS. 20 through 22 , a countersink  216  is provided coaxially aligned with each of first and second pin apertures  212 ,  214 . Countersinks  216  allow for a flush fit of a fastener head such as a spin rivet head when the fasteners are inserted through the pin apertures. An extending portion or stop boss  218  having an extension dimension “J” is positioned proximate to pin aperture  214 . As previously identified, stop boss  218  acts as a travel limiter for first flanged link  68  during pre-recline motion. Cylinder portion  208  has a total height “K” and through aperture  210  has a through aperture diameter “L”. In several embodiments of the present disclosure, height “K” is approximately 0.75 inches (1.90 cm), and diameter “L” is approximately 0.85 inches (2.16 cm). 
     Referring now generally to  FIGS. 23 through 25 , cam  98  includes a recessed body face  220  and a main body face  222 . A first, second and third detente aperture  224 ,  226 ,  228  are created in main body face  222 . Each of the first, second and third detente apertures  224 ,  226 ,  228  provide for engagement with a detente member (not shown) extending from second side plate  60 . A pin aperture  230  is provided to rotatably connect cam  98  to second side plate  60  using a fastener element such as a bolt or rivet. A raised inner ring  232  is located proximate to pin aperture  230  and a raised outer ring  234  is spaced outwardly from raised inner ring  232 , creating a biasing element retention slot  236 . A biasing element (not shown) such as a coiled spring can be positioned and retained within biasing element retention slot  236  providing a tensioning force to bias cam  98  against second side plate  60 . The biasing force can be adjusted making rotation of cam  98  easier or more difficult when changing between the various detente positions provided by first, second and third detente apertures  224 ,  226 ,  228 . Cam  98  is therefore rotatable about an aperture centerline  238  of pin aperture  230  by manually grasping extension element  132  and applying enough rotational force to overcome any biasing force of the biasing element positioned within biasing element retention slot  236 . 
     As further shown in reference to  FIG. 24 , cam  98  also includes each of a first, second, and third cam face  240 ,  242 ,  244 . Each of the first, second and third cam faces  240 ,  242 ,  244  are positioned sequentially closer to aperture centerline  238 . As cam  98  is rotated to the various detente positions, one of the first, second and third cam faces  240 ,  242 ,  244  contacts a cam link  245  providing an increasing extension length of first and second pantograph linkage sets  34 ,  35  . A weight bearing load of leg rest  24  increases as cam  98  is repositioned from contact with first cam face  240  up to contact with third cam face  244 . A dimension “K” is provided between aperture centerline  238  and first cam face  240 . A dimension “L” is provided between aperture centerline  28  and second cam face  242 . A dimension “M” is provided between aperture centerline  238  and third cam face  244 . Dimension “M” is greater than dimension “L” which is greater than dimension “K”, therefore allowing a greater extension of leg rest  24  when third cam face  244  is in contact with cam link  245  compared to either second or first cam faces  242 ,  240  respectively. As also shown in reference to  FIG. 25 , a cam mounting face  246  provides an alignment tab  247  extending substantially transverse to recessed body face  220 . Alignment tab  247  provides for improved alignment of cam  98  when cam  98  is originally installed on second side plate  60 . 
     Referring now to  FIGS. 26 and 27 , in other embodiments of the present disclosure, a non-adjustable cam  248  can be used in place of cam  98 . Non-adjustable cam  248  provides only a single face to engage cam link  245 . Non-adjustable cam  248  further includes a cam body  250  having a pin aperture  252  and a raised area  254  coaxially aligned with pin aperture  252  providing a bearing surface for a fastener to engage. A detente engagement aperture  256  is also provided which serves a similar function to any one of the first, second or third detente apertures  224 ,  226 ,  228 , allowing engagement with the detente element extending from second side plate  60 . Similar to cam  98 , non-adjustable cam  248  provides an alignment tab  258 . 
     Referring now to  FIGS. 28 and 29 , the installation of rear cross brace  56  to second rear support arm  54  is shown. Front cross brace  50  is installed in like manner and will therefore not be further discussed herein. Rear cross brace  56  includes a brace web  260  having each of a first and a second flange  262 ,  263  extending transversely therefrom at opposite ends of brace web  260 , thereby forming a substantially U-shaped channel. A portion of each of first and second flanges  262 ,  263  is removed and an end wall  264  is created by bending a portion of brace web  260  substantially transverse to its normal configuration. A partial cavity  266  is created between first flange  262  and end wall  264 . Partial cavity  266  has a cavity spacing “N”. Cavity spacing “N” substantially equals to a thickness of second rear support arm  54 . Second rear support arm  54  can therefore be slidably engaged within partial cavity  266  such that both an end face  269  of each of first and second flanges  262  and  263  and end wall  264  oppositely abut against second rear support arm  54 . A single fastener  268  is then inserted through end wall  264  and second rear support arm  54  to fastenably engage the assembly. By using partial cavity  266  created at both ends of rear cross brace  56  as well as front cross brace  50 , only a single fastener is required at the ends of the cross braces and significant stiffness is provided to resist side to side deflection of actuation mechanism  32 . Redundant or second fasteners are therefore eliminated for the front and rear cross braces  50 ,  56  of the present disclosure. 
     Referring now generally to both  FIGS. 30 and 31 , in several embodiments of the present disclosure, furniture member  10  can include a lever  270  in place of release latch  31 . Lever  270  is rotated in the direction of arc of rotation “L” to extend leg rest  24  about an arc of rotation “M”. In those embodiments where lever  270  is used, lever  270  is directly connected to drive rod  78 , thereby eliminating the need for trip lever  92  and trip lever biasing element  94 . Rotation of lever  270  overcomes the over-center bias provided by over-center toggle  84  to allow extension of leg rest  24 . 
     An in-line linkage mechanism or actuation mechanism of the present disclosure provides several advantages. By providing motion inserts having elongated slots, the linkage of actuation mechanism  32  provides a pre-reclining function for the seat back which requires no biasing element and returns by weight of the occupant to an upright position. The frame structure of the actuation mechanism of the present disclosure also provides a rigid structural cross brace design requiring only a single fastener for installation at opposite ends of the cross braces thereby eliminating weight while providing side to side rigidity for the actuation mechanism. The release mechanism using the trip lever and over-center toggle of the present disclosure provides for smooth operation of the actuation mechanism due to the polymeric material selected for these applications, which eliminates the need for lubrication of the sliding or rotating elements. The cam design of the present disclosure also permits an adjustment to be made for heavier or lighter weight occupants of the furniture member to balance the amount of load required to return the leg rest to the stowed position for occupants of varying weights and sizes. 
     The present disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.