NZ237726A

NZ237726A - Flexible stacking chair with one piece frame and pivotally connected seat and back

Info

Publication number: NZ237726A
Application number: NZ237726A
Authority: NZ
Inventors: Charles Owen Perry
Original assignee: Charles Owen Perry
Priority date: 1990-04-10
Filing date: 1991-04-08
Publication date: 1994-08-26
Also published as: AU7691691A; CA2080248C; ES2118081T3; AU651971B2; EP0539377A4; JPH0815446B2; WO1991015139A1; KR0182297B1; IL97762A; USRE36335E; JP3065274B2; CA2080248A1; DE69129628D1; JPH1033294A; EP0539377B1; DE69129628T2; EP0539377A1; JPH05507632A; ATE167369T1; IL97762A0

Abstract

A high density stacking flex chair is disclosed. A frame has a seat attached thereto, and a back pivotally attached thereto. The back is curved and can tilt backwards, but is limited by the frame which, through the back, has a lesser radius of curvature and is angled downward, thus providing stop action for back rotation.

Description

<div class="application article clearfix" id="description"> Priory D-:c('_): .IQ:WP!9 21222$ Cutup.wio I zis.ii-' :.L;o;"i Akicdofy. Ak7f.3/<**,;.... i • t • 111 * • > '.'.'.'fi'fi'AUe i99V'' I Li 1-. J V L. . _ I V«.vt • P."\ J?.::;.:!, i;o: Patents Form No. 5 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION f ,:f-8 f>W1991 ^ r- I «cE'5S-- HIGH DENSITY STACKING FLEX CHAIR oweN a£\^ 11 CHARLESPERRY, a US citizen of 20 Shorehaven Road, ■h*° - East Norwalk, Connecticut 06855, U.S.A. hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: - 1 - (followed by page la) 23 7 72 6 -la- HIGH DENSITY STACKING FLEX CHAIR BACKGROUND Field of the Invention The present invention relates to chair design, more specifically, to a design for a high density stacking chair with a tilting back. Discussion of the Prior Art The use of low-cost, stacking chairs is well-known in the art. However, such chairs are designed not with comfort or ergonomics in mind, but rather to provide a large quantity of temporary seats for occasional use which can ordinarily be stored and take up minimal storage space. Such chairs may have some limited flexibility in the seat back portion, but provide no ergonomic benefits. Considerable attention has been focused in recent years on better ergonomic designs, resulting in home and office chairs which demonstrate a wide variety of designs which include the ability to recline and provide lumbar support. See, for example, U.S. Patent No. 4,732,424. Such ergonomic designs do not, however, provide low cost seating. Thus, it: would be desirable to combine the benefits of ergonomic design into a low cost, stackable chair. ('■ -lb- 237726 SUMMARY OF THE INVENTION The invention provides a flexible chair comprising: (a) a seat adapted to engage a user's seat; (b) a back substantially perpendicular to said seat and adapted to engage a user's back and having a top and a bottom and upper and lower regions between the top and bottom; and (c) a flexible frame which holds and supports said seat and back, said frame comprising: (i) a pair of support legs one at each side of the seat with each support leg having (1) a resilient back leg portion pivotally attached to the upper region of said back below the top, (2) a bottom leg portion attached to the back leg (ii) a pivotal connection connecting the rear of the seat to the lower region of the back at a location substantially above the user's seat, wherein the flexibility of the legs and the pivotal connections permit the back to tilt toward a reclining position while the back functions as a lever against the resiliency of the back leg portion forcing the bottom of the back forwardly for lumbar support. A high density stacking chair with a tiltable back portion is presented, wherein a single continuous frame is provided, having a seat portion N.Z. PATENT OFF ICS portion extends along a floor surface, and 20 JUN1994 (3) a front leg portion attached to the bottom, leg portion extends upwardly to a front of said seat to support said seat, and receive (followed by page 2) 237726 -2- attached thereto, and a back portion pivotally attached thereto. Ergometric adjustment of the chair is accomplished by tilting of the back portion and flexure of the frame, and flexure of the frame urges 5 the back portion into a normal upright position for stacking and uniform appearance. The back portion is curved and hollow, and engages the frame at upper and lower curved sections of the frame, which sections have radii of curvatures less than that of the back 10 portion and which sections are positioned at a downward angle such that the effective horizontal radii of the sections in the upright position is shorter than the actual radii, causing the back portion to rest against the curved sections and limit. 15 forward tilting of the chair back. When the back portion is tilted, the radial movement disengages the j« * back portion from the curved sections due to the difference in radii, until the angle of tilt is such that the effective radii are again equal and the back 20 portion again rests against the curved sections' of the frame and limits tilting backward. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description of 25 the invention and accompanying drawings which set forth an illustrative embodiment in which the principles of the invention are utilized. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a chair built according to the present 30 invention. Fig. 2 is the preferred embodiment of a chair built according to the present embodiment. Figs. 3-5 are views taken across section 3-3 of Fig. 1 and showing the chair extending through its 35 range of backward tilt. 237726 -3- Fig. 6 is a view taken across Section 6-6 of Fig. 4 and represents a plan view of the chair according to the present invention. Fig. 7 is a perspective view of the chair 5 according to the present invention. DETAILED DESCRIPTION OF THE INVENTION Referring now to Fig. 1, a first embodiment of a chair according to the present invention is shown. There are three major portions of the chair: a frame 10 10, a seat portion 20, and a back portion 30. The back portion is curved to adapt to a user's back and is composed of a front section 32 and a rear section 34, each of which has a lip 33, 35 or other spacer which creates a hollow interior space between 15 sections when they are attached. The frame 10 is ideally a continuous structure, constructed of solid rod or tubular steel or the like. Alternatively, it may consist of welded or otherwise connected sections. The frame 10,has an 20 upper curved section 12 which is enclosed within the back portion 30 with cylindrical bearing sections 12a at either end and which extends through the middle of the back portion and is angled downward. The frame 10 then extends from each end of the upper curved 25 section 12 outward from the hollow interior, the back portion 30 being pivotally attached thereto at the cylindrical sections 12a. This pivotal attachment can be accomplished by bearings attached to the front section 32, but is preferably accomplished by 30 providing bearing surfaces 12b formed on plastic molded front and bach sections 32 and 34. The frame 10 has a pair of rear support legs 16 which extend downward and rearward to a floor surface and forwardly along the floor. A pair of front 35 support legs 18 then extend upward and rearward to the front of the seat portion 20, then rearward -4- 237726 supporting the seat portion 20, then slightly inward, then upward into the back portion 30, then inward, where the back portion is again pivotally attached in a manner similar to the pivot connection 12a and 12b. 5 The frame 10 continues to a lower curved section 14 which is enclosed within the back portion and which extends through the back portion having a downward angle. The distance dx between the opposing legs of the frame 10 as it sits on the floor is lesser than 10 the width d2 of the seat portion 20, so as to facilitate stacking a plurality of such chairs. In the preferred embodiment of Fig. 2, the seat supporting portion of the frame 10 is positioned inwardly from the edges of the seat portion 20 and 15 connected by welded struts 22 to improve the support of the seat portion and lateral stability of the frame. In Fig. 7, such lateral stability can be provided by a pair of stabilizers 50, 52. Additionally, clips 24 are attached to the bottom 20 surface of the seat portion 20 in order to easily attach/detach the seat portion to frame 10. The back portion 30 is a one-piece molded unit, having openings or clips 40 which are adapted to pivotally engage the rear support legs 16 at 25 cylindrical sections 12a. Openings or clips 42 are likewise adapted to pivotally engage the front support legs 18. In this way, the back portion 30 may be easily and securely fitted to frame 10. The curved sections 12 and 14 remain in a fixed position 30 relative to frame 10 to provide pivotal limits, as will be next described. Referring now to Figs. 3-5, the tilting action of the back portion 30 is illustrated. When the chair is in its upright position, as in Fig. 3, the 35 rear support legs 16 of the frame 10 are inclined at a forward angle so as to provide a natural spring- 237726 -5- type action which holds the back portion 30 forward. The curved sections 12 and 14 of frame 10 are parallel, each extending outward and downward from the back of the front section 32 at a twenty-two and 5 one-half degree angle. The radii of curvature for both curved sections 12 and 14 is lesser than that of the back portion. But, the radius of curvature of section 12 projected at a plane inclined to the plane of section 12 by an angle of 22.5 degrees equals the 10 radius of curvature of the back portion 30, such that the inside of the front section 32 is in contact with the curved sections 12 and 14 at points 36 and 37 as a result of the effective radius of the curved sections 12 and 14 being equal to the radius of the 15 back portion 30. As a user leans back on the chair, the front section 32 pivots about point 50 on the upper curved section, causing the upper half of the front section to rotate backwards, and the lower half to rotate 20 forward about point 50. Note also that the seat portion 20 will be lifted by the forward rotation of the lower curved section 14. Since the back portion 30 has a greater radius of curvature than both curved sections, the back portion lifts away from the curved 25 sections as it is tilted, reengaging the curved sections at points 38 and 39, located further down the back portion, where the effective radii of the back portion is again equal to the radii of the curved sections after the back portion has tilted 45 30 degrees. A clearer view of the relationship of the curved sections 12 and 14 to the overall frame structure 10 is illustrated in Fig. 6 where the cylindrical sections of the frame 12a are apparent providing 35 straight bearing areas. It should be understood that the invention is not intended to be limited by the specifics of the 237726 -6- above-described embodiment, but rather defined by the accompanying claims. </div>

Claims

<div class="application article clearfix printTableText" id="claims"> - 7 - 23 7 72 6 WHAT I CLAIM ISs

1. A flexible chair comprising: (a) a seat adapted to engage a user's seat; (b) a back substantially perpendicular to said seat and adapted to engage a user's back and having a top and a bottom and upper and lower regions between the top and bottom; and (c) a flexible frame which holds and supports said seat and back, said frame comprising: (i) a pair of support legs one at each side of the seat with each support leg having a resilient back leg portion pivotally attached to the upper region of said back below the top. a bottom leg portion attached to the back leg portion which extends along a floor surface, and a front leg portion attached to the bottom leg portion which extends upwardly to a front of said seat to support said seat, and (ii) a pivotal connection connecting the rear of the seat to the lower region of the back at a location substantially above the user's seat, wherein the flexibility of the legs and the pivotal connections permit the back to tilt toward a reclining position while the back functions as a lever against the resiliency of the back leg portion forcing the bottom of the back forwardly for lumbar support. (1) (2) N.2. PATENT OFFICE 20 JUN1994 (3) 23 7 726 - 8 -

2. The chair of claim 1 in which the pivotal connections at the upper and lower regions of the back comprise curved sections extending across the back limiting tilting of the back both toward and away from the reclining position.

3. The chair of claim 1 in which the back is pivotal with respect to the seat between upright and reclined positions in which at least one of the pivotal connections in the upper and lower regions of the back comprises: a section having a pair of coaxial pivot sections each coupled to opposite sides of the seat back and an intermediate section spaced apart from the axis of the pivot sections so that the intermediate section moves with respect to the back as the back and section pivot with respect to each other, stop surfaces on the back spaced apart from the axis of the pivot sections for engaging the intermediate section to provide pivotal limits in both the upright and reclined positions, and c) with the section and the resilient back leg portion of the chair resiliently urging the back into the upright position whereby the frame is resiliently biased at rest so that the back is in the upright position and whereby pressure of the user's back against the chair back causes the back to tilt with respect to the seat toward, but not beyond the reclined position. N.Z. PATENT OFFICE 20 JUN1994 (followed by page 9) 237 726 - 9 -

4. A flexible chair as claimed in claim 1, substantially as herein described with reference to any one of the Drawings. CHARLES 0 PERRY By his attorneys BALDWIN, SON & CAREY M 7. PATENT OFFICE 20 JUN1994 ~ REfflEHVP </div>