Abstract:
A gliding mechanism for a gliding recliner seating assembly comprises a floor-standing base having a longitudinal cross member parallel to a width of the seating assembly. Two front connecting links and two back connecting links respectively connect, pivotally, front and back portions of the seating assembly to the floor-standing base. The longitudinal cross member supports a weight transferred by the seating assembly to the floor-standing base and is positioned closer to the back portion of the seating assembly than to the front portion of the seating assembly. The gliding mechanism can be made part of a gliding recliner chair, for example an armchair, having vertical side frames pivotally connected to the floor-standing base. A footrest can be added to the seating assembly and be operated in extended position without preventing gliding movement of the chair. The floor-standing base may comprise a pivoting portion allowing rotation of the chair.

Description:
TECHNICAL FIELD 
     The present disclosure relates to glider chairs, and more particularly contemplates a gliding mechanism for a gliding recliner seating assembly. 
     BACKGROUND 
     Gliding chairs, including armchairs, have been in use for several years. For example, some armchairs are provided with a system that enables synchronized backrest reclining and footrest extension. There are also a few known pieces of furniture integrating a gliding motion and a backrest reclining/footrest extension system. Special devices such as pantographic actuators manufactured by LEGGETT &amp; PLATT®, Incorporated (Carthage, Mo.) are specifically engineered to enable the synchronized motions of backrest reclining and footrest extension. However, mounting pantographic actuators on a glider armchair is challenging if one wishes to preserve safe and user friendly operation. Therefore, no currently available chair allows the gliding action to take place while the backrest is operated in the reclined position and/or when a footrest is operated in the extended (usable) position. When installed on gliding chair, a locking device usually locks the seat in a predetermined position and prevents gliding when the backrest/footrest system is in the extended position so as to avoid accidents. 
     However, it would represent a significant advance in the art if a glider armchair user could pursue the gliding action with a reclined backrest and/or an extended footrest. There is thus a need for a novel gliding mechanism for a gliding recliner seating assembly offering gliding capability and concurrent backrest reclining and/or footrest deployment (extension) functions. 
     SUMMARY 
     According to a first aspect, the present disclosure provides a gliding mechanism for a gliding recliner seating assembly. The gliding mechanism comprises a floor-standing base having a longitudinal cross member parallel to a width of the seating assembly, and two front connecting links and two back connecting links for, respectively, pivotally connecting front and back portions of the seating assembly to the floor-standing base. The longitudinal cross member supports a weight transferred by the seating assembly to the floor-standing base and is positioned closer to the back portion of the seating assembly than to the front portion of the seating assembly. 
     According to a second aspect, the present disclosure provides a gliding recliner chair. The gliding recliner chair comprises a seating assembly and the aforementioned gliding mechanism. The seating assembly includes a backrest, left and right vertical side frames, and a seat extending between the left and right vertical side frames. The left and right vertical side frames are pivotally connected to the floor-standing base through the front and back connecting links. 
     According to a third aspect, the gliding recliner chair comprises a footrest operable between a retracted position and an extended position. Gliding movement of the seating assembly with respect to the floor-standing base is enabled when the backrest and the footrest adopt any of the retracted position or extended position. 
     According to a fourth aspect, the floor-standing base comprises a floor-engaging portion defining a floor-engaging planar perimeter having a longitudinal dimension in the direction of a gliding movement of the seating assembly. A normal projection of a center of gravity of a weight supported by the longitudinal cross member lies within the planar perimeter, generally spaced from the perimeter by a distance of at least about 15% of the longitudinal dimension, at any position of the gliding movement and at any position of the backrest and footrest. 
     According to a fifth aspect, the weight transferred by the seating assembly to the floor-standing base comprises a weight of the seating assembly alone or a combined weight of the seating assembly and of a user sitting on the seating assembly. 
     According to a sixth aspect, a center of a path followed by the center of gravity during a gliding movement with the backrest and footrest in the extended position is substantially in alignment with a vertical axis of the floor-standing base, the vertical axis being aligned with a center of the planar perimeter. 
     According to a seventh aspect, the floor-standing base further comprises a pivoting portion connected to the floor-engaging portion by a pivot, allowing a circular rotation about a vertical axis of the pivoting portion with respect to the floor-engaging portion. The vertical axis is aligned with a center of the floor-engaging planar perimeter. The connecting links are supported by the pivoting portion. 
     The foregoing and other features will become more apparent upon reading of the following non-restrictive description of illustrative embodiments thereof, given by way of example only with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the disclosure will be described by way of example only with reference to the accompanying drawings, in which: 
         FIGS. 1   a  and  1   b  are left side elevation views of a gliding recliner armchair with backrest and footrest in a fully extended position with a gliding system (a) at a foremost position and (b) at a backmost position, a user sitting on the gliding recliner armchair; 
         FIGS. 2   a  and  2   b  are partial views of  FIGS. 1   a  and  1   b  detailing a path of the center of gravity (chair and user) upon gliding movement between (a) the foremost position and (b) the backmost position; 
         FIGS. 3   a  and  3   b  are left side elevation views of the gliding recliner armchair of  FIGS. 1   a  and  1   b  with backrest and footrest in a fully extended position and the gliding system (a) at the foremost position and (b) at the backmost position, with no user sitting; 
         FIGS. 4   a  and  4   b  are left side elevation views of the gliding recliner armchair of  FIGS. 1   a  and  1   b  with backrest and footrest in a fully retracted position and the gliding system (a) at the foremost position and (b) at the backmost position, with a user sitting; 
         FIGS. 5   a  and  5   b  are left side elevation views of the gliding recliner armchair of  FIGS. 1   a  and  1   b  with backrest and footrest in a fully retracted position and the gliding system (a) at the foremost position and (b) at the backmost position, with no user sitting; 
         FIGS. 6   a  and  6   b  are left side elevation views of the gliding recliner armchair of  FIGS. 1   a  and  1   b  alone in a normal rest position, with backrest and footrest in (a) a fully retracted position and (b) a fully extended position; 
         FIGS. 7   a  to  7   e  show different views of the gliding recliner armchair of  FIGS. 1   a  and  1   b  with backrest and footrest in a fully retracted position: (a) left side view, (b) front elevation view, (c) detail of front view, (d) partial isometric view and (e) detail from partial isometric view; 
         FIGS. 8   a  and  8   b  respectively show a top view and a cross-sectional elevation view of a floor-engaging portion of the gliding recliner armchair of  FIGS. 1   a  and  1   b ; and 
         FIGS. 9   a  to  9   d  show various views of a pivoting portion according to the gliding recliner armchair of  FIGS. 1   a  and  1   b : (a) top side isometric view, (b) top view, (c) front elevation view and (d) cross-sectional view of the left side as viewed from line A-A of  FIG. 9   c.    
     
    
    
     DETAILED DESCRIPTION 
     Like numerals represent like features on the various drawings. 
     Various aspects of the present disclosure generally address one or more of the problems related to the operation of a glider chair. More particularly, aspects of the present disclosure address problems related to the operation of a glider armchair providing backrest reclining and footrest deployment (extension) functions. Operation of the backrest/footrest functionalities of the glider armchair, without preventing gliding motion, is further addressed. 
     An embodiment of a gliding mechanism for a gliding recliner chair and of a gliding recliner armchair with footrest comprising the gliding mechanism, will now be described in details referring to the appended drawings. However, at least some of the teachings of the present disclosure are applicable to glider chairs without armrest and/or without footrest. The following description of a gliding recliner armchair with footrest is illustrative only and is not intended to limit the applicability of the gliding mechanism to other types of glider chairs. 
     Referring to  FIGS. 7   a - 7   e , there is illustrated a gliding recliner armchair  100  comprising a seat  10  and backrest  12  assembly mounted on a pair of parallel spaced apart pantographic backrest/footrest actuators  40   a - 40   b  assembled on a cross member  22  extending between and connecting first  20   a  and second  20   b  vertical side frames together to form a seating assembly. The actuators  40   a - 40   b  enable reclining movement of the backrest synchronized with seat displacement with respect to frames  20   a - 20   b  and extension of a footrest plate  41  (see  FIGS. 1 to 6 ). Upper portions  21   a - 21   b  of the frames  20   a - 20   b  can be used as armrests. Alternatively, separate padded armrest members (not shown) can be mounted to the upper portions  21   a - 21   b , using screws for example. Of course, a glider chair using the present gliding mechanism may be provided without armrests. 
     Each of side frames  20   a - 20   b  is operatively connected to a floor-standing base  50 . Connection of the floor-standing base  50  to the side frames  20   a - 20   b  is made through connecting links  30   a - 30   d . Bolts or studs  33   a - 33   d  attach the connecting links  30   a - 30   d  to the side frames  20   a - 20   b  and bolts or studs  34   a - 34   b  attach the connecting links  30   a - 30   d  to the floor standing base  50 . More specifically, the connecting links  30   b  and  30   d  connect a front portion of the floor-standing base  50  to front portions of the side frames  20   a - 20   b  using bolts or studs  33   b ,  33   d ,  34   b  and  34   d . Likewise, the connecting links  30   a  and  30   c  connect a back portion of the floor-standing base  50  to back portions of the side frames  20   a - 20   b  using bolts or studs  33   a ,  33   c ,  34   a  and  34   c . The bolts or studs  33   a - 33   d  and  34   a - 34   d  are configured to allow pivoting of the connecting links  30   a - 30   d , in order to enable gliding movement of the seating assembly with respect to the floor-standing base  50 , as it is known in existing glider armchairs. For example a front pivoting point P 1  is formed by bolt or stud  33   b  and a back pivoting point P 2  is formed by bolt or stud  34   a . Front links  30   b  and  30   d  are transversely connected together by a rod  31  and links  30   a  and  30   c  are transversely connected together by a rod  32  to ensure coordinated movement. The floor-standing base  50  comprises a pivoting portion  51  ( FIGS. 9   a - 9   d ) assembled on a circular floor-engaging portion  58  for pivotal movement about a vertical axis  56 . 
     Referring more specifically to  FIGS. 9   a - 9   d , the pivoting portion  51  comprises a longitudinal cross member  53  connected at each end to braces  55   a - 55   b  so that the cross member  53  is parallel to a width of the pivoting portion  51  and with a width of the seating assembly. A center post, or pivot  52 , is mounted on the cross member  53  for pivotally engaging a bore  57  and bushing (not shown) provided at the center of the floor-engaging portion  58  at the axis  56 , which is perpendicular to the plane of a perimeter  59  of the floor-engaging portion  58 . The symmetry of the perimeter  59  allows the armchair  100  to recline and glide in any radial orientation of the seating assembly in relation to the floor-engaging portion  58 . 
     In an alternative embodiment of the gliding recliner armchair  100 , a circular rotation of the seating assembly about the axis  56  may not be provided. In this alternative embodiment, the pivoting portion  51  is fixedly connected to the floor-engaging portion  58 . 
     Unlike known gliding armchairs, links  30   a - 30   d  are mounted on the inside of the pivoting portion  51  but outside of the pantographic actuators (between the actuators  40   a - 40   b  and the pivoting portion  51 ). This special feature enables the use of a relatively wider and more comfortable footrest plate  41  extending between the side frames  20   a - 20   b  without interfering with the floor-standing base  50  during gliding when the footrest actuators  40   a - 40   b  are retracted. 
     At least one stop pin  54  (here, one is provided on each side) is provided to define a backmost position of gliding when links  30   b  and  30   d  abut thereon. Contact of links  30   a - 30   b  with cross member  53  acting as a stop member defines the foremost allowed position of gliding. 
     Referring to  FIGS. 1   a  and  1   b , the armchair  100  is shown with a user in a sitting position and with the actuators  40   a - 40   b  extended to provide reclined backrest  12  and deployed footrest  41 . A representative user selected for stability studies was 6 foot tall and weighed about 180 pounds. In  FIG. 1   a , the armchair is shown in a foremost position of the gliding movement and in  FIG. 1   b  the armchair in shown in a rearmost position of the gliding movement. Vertical phantom lines are provided: Line C showing the center axis of the pivot  52  and bore  57  supporting the pivoting portion  51 , line Pb being a normal projection of the backmost end of the perimeter  59  of the floor-engaging portion  58 , and line Pf being a normal projection of the foremost end of the perimeter  59 . 
       FIGS. 2   a  and  2   b  represent the same respective armchair positions but with a partial view to better show a path  90  followed by the center of gravity during gliding. Gf indicates the instant position of the center of gravity in the position of  FIG. 1   a  (foremost) and Gb indicates the instant position of the center of gravity in the position of  FIG. 1   b  (backmost). 
     As can be appreciated, the present design limits displacement of the center of gravity of the present gliding recliner armchair in the most extreme conditions, i.e. reclined backrest  12  and deployed footrest  41 . A center  91  of the path  90  followed by the center of gravity is substantially normal to the vertical axis  56  of the floor-standing base  50 . By reducing the displacement of the center of gravity along the path  90  in proximity with the vertical axis  56  of the floor-standing base  50 , it is possible to provide a gliding recliner armchair with a reclinable backrest, and deployed footrest, which can be safely glided in its fully open position.  FIGS. 2   a  and  2   b  further show that at any particular gliding position, the projection of the combined center of gravity along an axis normal to the plane of the perimeter  59  always falls within the perimeter delimited by lines Pf and Pb. Moreover, one may observe that the projections of Gf and Gb in these critical positions are still away from Pf or Pb by a ratio of about ⅓ of a dimension L corresponding to the base perimeter (substantially equal to the diameter of floor-engaging portion  58 ). Given the symmetry of the floor-engaging portion  58 , this holds true for any angular position of the armchair about the central axis C. A ratio higher than about 20% has been found by experience to provide sufficient stability. 
     Therefore, it can be seen that the cross member  53  supporting the upper portion of the armchair  100  on the floor-engaging portion  58  is not centered between the front and back pivoting points (for example P 1  and P 2  on  FIG. 9   d ) of links  30  on the pivoting portion  51  but is rather strategically positioned rearward to enable a stable and safe behavior of gliding movement in reclined and footrest extended position with respect to the center of gravity. 
     On  FIG. 9   d , a horizontal distance d 1  between the front pivoting point P 1  and the vertical axis  56  is about 1.85 times a horizontal distance d 2  between the vertical axis  56  and the back pivoting point P 2 . This relation between values of d 1  and d 2  is illustrative and non-limiting. Some variations of a ratio of d 1  over d 2  are contemplated. For example d 1  can be greater than d 2  by a factor in a range between about 1.6 and 2. 
     In one practical and non-limiting realization, the floor-engaging portion  58  has a base perimeter L equal to 26 inches while the seat  10  has a depth of 20 inches. On  FIG. 7   a , which shows the gliding recliner armchair unloaded (without user) with the backrest and footrest in fully retracted position, a front edge of the seat  10  extends beyond the diameter of the floor-engaging portion  58  by about one (1) inch and a rear edge of the seat  10  lies within the diameter of the floor-engaging portion  58  by about seven (7) inches. Consequently, the seat  10  is centered longitudinally about four (4) inches forward in relation to the vertical axis  56 . 
     Workable values of the ratio of d 1  over d 2 , the sizes of the floor-engaging portion  58  and of the seat  10 , and relative positions of the seat  10  and of the floor-engaging portion  58  are expected to vary according to selected dimensions of various components of the gliding mechanism and of the gliding recliner seating assembly, and according to the intended use of the gliding mechanism and of the gliding recliner seating assembly. 
       FIGS. 3   a  and  3   b  show the gliding recliner armchair with only the footrest extended in respectively the most frontward and rearward positions. As depicted, at the most frontward and rearward gliding positions, the center of gravity of the armchair with the footrest extended remains within slightly less extremes and safer limits than the displacement represented in  FIGS. 2   a - 2   b  previously discussed. The reduced movement of the gravity center indicates that the presence of a user has minimal influence on the stability in this situation, and that geometric properties and material selection of the armchair  100  would hold safe operation for a very wide range of anthropometric characteristics. Steel or any material with similar solidity characteristics is selected for adequate rigidity of the armchair structure and for proper balancing. Of course, this does not apply to cushioning, to seat and backrest suspension or to cosmetic make up. 
       FIGS. 4   a - 4   b  and  5   a - 5   b  show that stability is also kept within a similar safety range when the footrest  41  and backrest  12  are set in the retracted position, with or without a user sitting. Actually, the most critical position a user may experience is with the footrest  41  retracted when reaching the foremost gliding position. Still, in the stability studies for the 6 foot tall, 180 pounds representative user, the projection of Gf in  FIG. 4   a  remained inside the perimeter  59  and away from line Pf by about 17% of L, as illustrated on  FIG. 4   a . This situation is considered acceptable by experience considering that forward tilting of the armchair doesn&#39;t occur without excessive forward projection of the user&#39;s body and the user may easily put his feet on the floor and stand up from the sitting position. It is envisioned that any projection of Gf at least 15% away from line Pf provides safe operation of the gliding recliner. Therefore, the built-in safety factor is higher for the extended position and backmost gliding attitude since backward tilting theoretically presents a higher risk of injury. 
     The difference between the resting position of the armchair  100 , with backrest  12  and footrest  41  in (a) a fully retracted position and (b) a fully extended position is shown at  FIGS. 6   a  and  6   b . It can be seen that the reclining actuators  40   a - 40   b  do not change the relative angle between the seat  10  and the backrest  12 , but cause this seat  10  and backrest  12  assembly to slide and tilt in the backward direction. A user may perform the displacement from retracted position to reclined position, simply by urging his back against the backrest while pushing forward on the frames  20   a - 20   b  and unfolding his legs. At rest, in either position, the center of gravity is very close to the center axis C of the pivot  52  and naturally slightly forward in the reclined position. 
     One may therefore appreciate that the afore described embodiment of the gliding recliner armchair with footrest provides a safe, reliable and cost effective way of enabling gliding and backrest reclining/footrest deployment operable simultaneously in a same piece of furniture. Therefore, it can be seen that the armchair according to the present disclosure overcomes the limitations, drawbacks and shortcomings of existing gliding recliners. 
     Although the present gliding mechanism has been described hereinabove by way of non-restrictive, illustrative embodiments thereof, these embodiments may be modified at will within the scope of the appended claims without departing from the spirit and nature of the present disclosure.