Abstract:
A chair support arrangement for permitting tilting of a chair seat and chair back assembly by a sitter thereon. The assembly comprises a chair base having a chair support arm extending therefrom, and a flexpad support arrangement secured to the chair support arm. The flexpad support arrangement comprises a compressible pad having compressible contoured portions to facilitate yielding of the flexpad and tilting of the chair seat and chair back assembly. The compressible contoured portions comprise a front edge and a rear edge of said flexpad. The contours may be comprised of an array of furrows parallel to one another and to the upper and lower surfaces of the pad.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to supports for chairs, and more particularly to flexible support arrangements for supporting a tiltable chair seat and seat back.  
         [0003]     2. Prior Art  
         [0004]     Providing a comfortable seat for a wide variety of seat occupants is always a challenge. Such a capability must be present in public seating arrangements, for example such as those found in the health care market. Such a seat must be comfortable and somewhat maneuverable for a wide range of people, be they heavy or light, wide or narrow. Such seat accommodations should also be non-adjustable in their tilting capacities. The chair and furniture industry have yet to provide such a simple, widely utilizable chair arrangement in an inexpensive format, particularly to service the healthcare market. My earlier patents U.S. Pat. Nos. 4,871,208 and 5,649,740 are cited herein as prior art, and are also incorporated herein by reference.  
         [0005]     It is an object of the present invention, to overcome the disadvantages of the prior art chair support assemblies.  
         [0006]     It is a further object of the present invention to provide a chair support arrangement which will be passive yet very accommodating in its capability to provide comfortable yet tiltable accommodative support front and back as well as side to side, thus a 360 degree range of tiltable motion, for a wide variety of users.  
         [0007]     It is still yet a further object of the present invention, to provide a chair support arrangement which has a wide range of embodiments which may be selected by the manufacturer thereof.  
       BRIEF SUMMARY OF THE INVENTION  
       [0008]     The present invention relates to a chair assembly, preferably comprising a molded chair seat back unitarily molded with a chair seat. That seating surface is supported on a wheeled base, by a height-adjustable column having an upper end with a chair support arm arranged thereon. The chair support arm has a distal end which supports a flexpad support arrangement thereon. The flexpad support arrangement is secured between the distal end of the chair support arm and the lower side of the molded chair seat.  
         [0009]     The flexpad support arrangement comprises a bottom mounting plate mounted securely to the distal end of the chair&#39;s support arm. The bottom mounting plate is preferably of rectangular configuration. A bolt-receiving lower housing is attached to the lower side of the bottom mounting plate.  
         [0010]     A flexpad comprised of compressible, resilient material is disposed on the top side of the bottom mounting plate. The flexpad is sandwiched between the bottom mounting plate and an upper mounting plate. The upper mounting plate is attached to the molded chair seat portion by an arrangement of seat securement bolts. An elongated flexible support arrangement securement bolt is disposed through the upper mounting plate, then through a bore located just forward of the geometric center of the flexpad, and through an opening in the bottom plate and through the bolt-receiving lower housing and locked therein by a bolt lock washer slid into a groove on the lowermost end of the flexible support arrangement securement bolt. The bolt lock washer is secured to the bottom side of the bolt-receiving lower housing by for example, a washer lock pin.  
         [0011]     The compressible flexpad itself, in a first preferred embodiment thereof, comprises a multi-sided block of compressible material having a rear edge, a front edge, which is shorter width-wise than the rear edge. The rear edge has angled corners leading to a side edge, the side edges having angled portions which lead to the narrower front edge of the flexpad.  
         [0012]     In a first preferred embodiment of the flexpad arrangement, the rear edge of the flexpad has a plurality of furrows arranged transversely thereacross, parallel with the upper and lower surfaces of the flexpad. The front edge of the flexpad has a plurality of furrows or channels disposed horizontally thereacross. Those furrows run parallel with respect to and between the upper and lower surfaces of the flexpad. In the preferred embodiment of the flexpad arrangement, the number of furrows across the front edge of the flexpad is greater than the number of furrows disposed across the rear edge of the flexpad. These furrows extending across the read edge of the flexpad extend into the corner portions of the rear side, those furrows tapering until they have a depth of zero before reaching the side edge of the flexpad.  
         [0013]     The furrows in the front edge of the flexpad extend into the corner portions of the front edge and taper to a depth of zero at the corner portions thereof. It is intended that the side edges of the flexpad have no furrows, channels or indentations thereon. The front and rear wall portions of the flexpad comprise the “stretched” and “squeezed” portions of the flexpad, the side wall portions having little or no stretch or compression thereat inasmuch as side tilting is somewhat minimal compared to the front and rear tilting.  
         [0014]     In a further embodiment of the present invention, it is intended that the furrows on the rear edge have a sharpened cut thereto, having edges when viewed in a cross sectional viewing thereof. It is also intended at the furrows on the front edge of the flexpad have a cross-sectional representation with sharp edges or corners thereon. Those furrows being in greater number than those formed in the rear edge thereof.  
         [0015]     An arrangement of pad bores or material removing voids may be disposed across the rear section of the flexpad extending preferably through the top and bottom surfaces thereof. These pad bores permit a certain inwardly directed flexing in inward bulging, when the flexpad is compressed, to minimize the outward bulging of the sides or end portions of the flexpad. The bore hole for the securement bolt is arranged in a geometically forward location from the center of the center of the flexpad. The bore hole for the securement bolt may be shaped to accommodate the tapered head of the bolt, therein.  
         [0016]     In a further preferred embodiment of the present invention, the flexpad may be of somewhat a “D” shape, having curved front side portions and a rather short front edge, and an elongated rear edge with curved rear side portions thereon. In yet a further embodiment of the furrows arranged therein, such adjacently arranged parallel furrows may in a transverse sectional appearance look like a curved sinusoidal pattern or curved surface with one or two or three or more furrows defining the front edge of those waves on the flexpad. A front edge of those furrows in that particular embodiment, may also be sinusoidally curved with a shorter wave height/depth to that curve and with more curves between the lower and the upper edge of the flexpad. Such furrows or sinusoidal curves would extend into the corner portions of the respective front and rear edges. Such sinusoidal furrows would preferably be tapered to a zero depth as it approached the respective side edges. Those side edges would preferably be smooth.  
         [0017]     It is intended that the non-adjustable flexpad accommodate a wide range of weights and sizes, and permitting the seat back and seat chair (a shell) to tilt forwardly a slight amount and rearwardly a greater amount by compressing their respective front or rear edges along those particular furrows disposed therein, as well as limited side to side tilting. The flexpad may also be pre-compressed at assembly of the flexpad support arrangements between the upper and lower mounting plates in a further embodiment thereof.  
         [0018]     Thus there has been shown a flexpad support arrangement with a uniquely designed flex pad between and upper and lower mounting plate, that flexpad having a unique combination of furrows or indentations along its rearward side and its frontward side and in one preferred embodiment having somewhat hard corners or side edges. The furrows being of different numbers and depths between the front and rearward sides or accommodation thereof, to seat a wide range of people sitting thereon.  
         [0019]     The invention thus comprises a chair support arrangement for permitting limited forward and rearward tilting of a chair seat and chair back assembly by a sitter thereon. The arrangement comprises a chair base having a chair support arm extending therefrom; and a flexpad support arrangement secured to the chair support arm wherein the flexpad support arrangement comprises a compressible pad having compressible contoured portions to facilitate yielding of the flexpad and tilting of the chair seat and chair back assembly. The compressible contoured portions may comprise a front edge and a rear edge of the flexpad. The front edge and the rear edge preferably have a plurality of furrows arranged thereon. The front edge of the flexpad preferably has a greater number of furrows thereon than the rear edge of the flexpad. The furrows preferably comprise channels disposed parallel to an upper surface and a lower surface of the flexpad. The furrows may be channels having sharp or “defined” edges thereon. The furrows may be channels having a sinusoidally shaped cross-section thereto. The compressible pad is preferably sandwiched between an upper support plate and a lower support plate. A securement bolt is arranged through the upper support plate and the lower support plate with the pad sandwiched therebetween. The securement bolt extends through a bolt hole in the pad, wherein the bolt hole is disposed in a location forward of the geometric center of the pad. The pad may be pre-compressed between the upper support plate and the lower support plate. The contoured portions may also include rear corner portions and front corner portions thereon. The corner portions may have furrows extending onto at least a portion thereof. The furrows in the corner portions taper in dimensionally to depth of zero thereat. The pad has a generally linear front edge and a generally linear rear edge. The pad may be of a generally “D” shape in a plan view. The pad may have side wall portions of generally smooth configuration. The pad may have a plurality of pad bores therein to permit the pad to “belly-in” during compression of the pad between the upper and lower support plates.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]     The objects and advantages of the present invention will become more apparent, when viewed in conjunction with the following drawings, in which;  
         [0021]      FIG. 1  is a side elevational view of a chair assembly constructed according to the principles of the present invention;  
         [0022]      FIG. 2  is a perspective exploded view of the flexpad support arrangement of a chair constructed according to  FIG. 1 ;  
         [0023]      FIG. 3  is a plan view of a flexpad of the present invention;  
         [0024]      FIG. 4  is a view taken along the lines  4 - 4  of  FIG. 3 ;  
         [0025]      FIG. 5  is a plan view of a further embodiment of the flexpad with rounder, softer curved edges thereon; and  
         [0026]      FIG. 6  is a sectional view taken along the lines  6 - 6  of  FIG. 5 .  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]     Referring now to the drawings in detail, and particularly to  FIG. 1 , there is shown the present invention which includes a chair assembly  10 , preferably comprising a molded chair seat back  12  unitarily molded with a chair seat surface  14 . That seating surface  14  is supported on a wheeled base  16 , by a height-adjustable column  18  having an upper end hub  20  with a chair support arm  22  arranged thereon. The chair support arm  22  has a distal end which supports a flexpad support arrangement  24  thereon. The flexpad support arrangement  24  is secured between the distal end of the chair support arm  22  and the lower side of the molded chair seat  14 .  
         [0028]     The flexpad support arrangement  24 , shown more clearly in an exploded view in  FIG. 2 , comprises a bottom mounting plate  26  mounted securely by welding or the like, to the distal end of the chair&#39;s support arm  22 . The bottom mounting plate  26  is preferably of rectangular configuration. A bolt-receiving lower housing  28  is attached to the lower side of the bottom mounting plate  26 .  
         [0029]     A flexpad  30  comprised of compressible resilient material such as for example, rubber or neoprene, is disposed on the top side of the bottom mounting plate  26 . The flexpad  30  is sandwiched between the bottom mounting plate  26  and an upper mounting plate  32 . The upper mounting plate  32  is attached to the molded chair seat portion  14  by an arrangement of seat securement bolts  34 . An elongated flexible support arrangement securement bolt  36  is disposed through an opening  38  in the upper mounting plate  32 , then through a bore  40  located just forward of the geometric center of the flexpad  30 , and through an opening  42  in the bottom plate  26 , and through the bolt-receiving lower housing  28  and locked therein by a bolt lock washer  44  slid into a groove  46  on the lowermost end of the flexible support arrangement securement bolt  36 , as represented in  FIG. 2 . The bolt lock washer  44  is secured to the bottom side of the bolt-receiving lower housing  28  by a washer lock pin  48 .  
         [0030]     The compressible flexpad  30 , in a first preferred embodiment thereof as represented in  FIGS. 3 and 4 , comprises a multi-sided block of compressible material having a linear rear edge  50 , a linear front edge  52 , which is shorter width-wise than the rear edge  50 . The rear edge  50  has generally linear angled corner portions  54  leading to a linear side edge  56 . The side edges  50  and  52  having generally linear front angled portions  58  which lead to and blend in with the narrower front edge  52  of the flexpad  30 .  
         [0031]     In a first preferred embodiment of the flexpad  30 , as represented in  FIGS. 3 and 4 , the rear edge  50  of the flexpad  30  has a plurality of furrows  60  arranged transversely thereacross, parallel with the upper and lower surfaces  62  and  64  of the flexpad  30 . The front edge  52  of the flexpad  30  has a plurality of furrows  66  or channels disposed horizontally thereacross, as represented in  FIGS. 3 and 4 . Those front furrows  66  run parallel with respect to and between the upper and lower surfaces  62  and  64  of the flexpad  30 . In one preferred embodiment, the furrows may be also curved along their longitudinal direction (not shown for clarity). In another preferred embodiment of the flexpad  30 , the number of furrows  66  across the front edge  52  of the flexpad  30  is greater than the number of furrows  60  disposed across the rear edge  50  of the flexpad  30 . These furrows  60  extending across the rear edge  50  of the flexpad  30  extend into the corner portions  54  of the rear side, those furrows  60  tapering down until they have a depth of zero before reaching the side edges  56  of the flexpad  30 , as represented in  FIG. 1  and  FIG. 3 .  
         [0032]     The furrows  66  in the front edge  52  of the flexpad  30  extend into the corner portions  58  of the front edge  52  and taper to a depth of zero at the corner portions thereof, as represented in  FIGS. 1 and 3 . It the preferred that the side edges  56  of the flexpad  30  have no furrows, channels or indentations thereon. The side to side tilting therefore, will be not as extensive as the front to rear tiltability of the chair assembly  10 .  
         [0033]     In a further embodiment of the present invention, as represented in  FIGS. 3 and 4 , it is intended that the furrows  60  on the rear edge  50 , have a sharpened cut thereto, having edges  70  when viewed in a cross sectional viewing thereof, shown in  FIG. 4 . It is also intended at the furrows  66  on the front edge  52  of the flexpad  30  may also have a cross sectional representation with the “hard” or somewhat sharp edges or corners  70  thereon, as again represented by  FIG. 4 . Those furrows  66  on the front side  52  preferably being in greater number than those formed in the rear edge  50  thereof to give greater tiltability in one direction (forward) than over the other direction.  
         [0034]     An arrangement of pad bores or material removing voids  72  may be disposed across the rear section of the flexpad  30  extending preferably through the top and bottom surfaces  62  and  64  thereof. These pad bores  72 , shown in  FIGS. 1, 3  and  5 , permit a certain inwardly directed flexing and inward bulging, when the flexpad  30  is compressed by a sitter on the chair assembly  10 , to minimize the otherwise outward bulging of the sides  56  or end portions  50  and  52  of the flexpad  30 . The bore hole  40  for the securement bolt  36  is arranged in a geometrically forward location from the center of the center of the flexpad  30 , as represented in  FIGS. 3, 4 ,  5  and  6 . The bore hole  40  for the securement bolt  36  may have an “indented” or curved shape  74 , as represented in  FIGS. 3 and 5 , so as to accommodate the tapered head  76  of the bolt  36 , therein.  
         [0035]     In a further preferred embodiment of the present invention as represented in  FIGS. 5 and 6 , the flexpad  30  may be of somewhat a “D” shape, having curved front side portions  76  and a rather short linear front edge  78 , and an elongated generally linear rear edge  80  with curved rear side portions  82  thereon, best represented in  FIG. 5 . In yet a further embodiment of furrows arranged in the flexpad  30 , such adjacently arranged rear parallel furrows  84  may in a transverse sectional appearance look like a curved sinusoidal pattern or curved surface and with one or two or three or more furrows  86  defining the front edge  78  of those waves on the flexpad  30 . A front edge of those furrows in that particular embodiment, may also be sinusoidally curved with a shorter wave height/depth to that curve and with more curves between the lower and the upper surfaces  62  and  64  of the flexpad  30 . Such furrows or sinusoidal curves  86  and  84  would extend into the corner portions  76  and  90  of the respective front and rear edges  78  and  80 . Such sinusoidal furrows  84  and  86  would preferably be tapered to a zero depth as they approach their respective side edges  92 . Those side edges  92  would preferably be smooth.  
         [0036]     It is intended that the non-adjustable flexpad  30  is calibrated by its thickness, durometer and profile to comfortably accommodate a wide range of weights and sizes, and permitting the seat back  12  and seat chair portion  14  to tilt forwardly a slight amount and rearwardly a slight amount, as represented by arrow “A” in  FIG. 1 , by compressing their respective front or rear edges  52  and  50  along those particular furrows  66  and  60  disposed therein, as well as some side to side movement. The flexpad  30  may be pre-compressed at assembly of the flexpad support arrangements between the upper and lower mounting plates  32  and  26  in a further embodiment thereof.  
         [0037]     Thus there has been shown a flexpad support arrangement with a uniquely designed flexpad between and upper and lower mounting plate, that flexpad having a unique combination of furrows or indentations along its rearward side and its frontward side and in a preferred embodiment having somewhat hard corners or side edges. The furrows being of different numbers and depths between the front and rearward sides or accommodation thereof, to seat a wide range of people sitting thereon.