US2851086A - Lock for folding chairs - Google Patents

Description

Se pt.9,1958 mcwgma v 2,851,086

' LOCK-FOR FOLDING CHAIRS Filed Sept. 20, 1955 2 Sheets-Sheet 1 Meyer C. we) er Afforney P 1958 M. c. WElNER 2,851,086

LOCK FOR FOLDING CHAIRS Filed Sept. 20, 1955 2 Sheets-Sheet 2 J I L-292 v /;g. I Make! C. We/her" I: Y-

" Affomev;

United Stae This invention relates to the construction of folding chairs, and has .been developed primarily to cope with the problems present in the adaptation of a folding mechanism to childrens highchairs. The notorious tendency for children to occupy chairs in strange attitudes,- and to shift their weight continually and with violence from one part of the chair to the other makes it imperative that the folding mechanism be designed to accommodate such conditions without establishing any tendency to move the chair toward the folded condition, or to otherwise endanger the occupant. In additionto the unpredictable behavior of the occupant of the chair, outside forces are often brought to bear which must be accounted for in the design of the mechanism. It is often desirable/to drag an occupied chair across the floor from one part of'the room totheother, and such a maneuver will apply substantial forces to the legs and folding linkage which are very difficult topredict. The chair can be moved in such a fashion that the principal portion of the weight is supported in an almost endless variety of weight-distribution combinations between the several legs, and any mechanical linkage is normally quite sensitive in its behavior to the direction of applied forces with respect to the pivot points. A folding chair mechanism of conventional type which will accommodate all of these unpredictable conditions Without disturbing the stability of the chair would be most remarkable; and if available at all, would carry with it the likelihood of prohibitive cost.

In view of the difficulty of designing a mechanism which would, in and of itself, accommodate all of the infinite changes in condition to which the chair is subjected, applicant has discovered a system which can be incorporated in a relatively conventional folding chair mechanism which will adequately lock the structure in the erected condition so that no amount of mistreatment will serve to move the chair toward a folded or otherwise unstable position.

The several features of the invention will be analyzed in detail through a discussion of the particular embodiments illustrated in the accompanying drawings. In the drawings:

Figure 1 presents a perspective view in side elevation of a chair embodying this invention.

Figure 2 presents a perspective view of the same chair in the folded condition.

Figure 3 shows a fragmentary view on an enlarged scale of the locking mechanism, as seen directly from the rear.

Referring to the drawings, the illustrated chair includes a back unit composed of an upholstered section and a pair of opposite arms 11 which are each attached to the lower part of the upholstered unit and extend downwardly in a curved configuration. The lower part of each of the arms 11 is pivotally connected at 12 to the seat unit 13. Opposite arm rests 14 are pivotally connected to the upper end of the arms 11 at points as indicated at 15 in Figure 1.

The front legs 16 and 17 are each pivotally connected atent O "ice shown at 24, with the opposite ends being connected to the arms 11 at the abutments 25. The construction of the abutments is best indicatedin Figure 3, and includes a bolt 26fitted with a suitable spacingwasher 27,

and with a resilient tubular member 29 forabsorbing the shock as the rear legs comeinto engagement therewith. The nut 30 completes the assembly,.and .it should be observed that the abutment 25 is positioned-so thatit limits the rearwardswing of the rear legs about thepivot points 22 with respect to the backand seat. When the chair is in the erectcondition, the upholstered-unit 10 and .theseat unit 13 have a relativelyfixed relationship, and

cant has provided a latch in the form of a. hook-shaped member 31 pivotally connected to eachof the. rear legs at the point indicated at'32. The lower extremity 33 (see Figure 3) of the hook member 31 engages the abutment 25 when the chair is in erect position. Such engagement securely locks the folding action of the chair, since it is no longer possible for the rear legs 20 and 21 to move forwardly with respect to the seat away from the abutment 25. The upper portion of the hook member 31 may be formed in some convenient fashion to provide an effective grip for engagement of the finger to facilitate the unlocking of the chair prior to folding it. i

A tray 34 is mounted on the arms 14 with a conventional positioning adjustment mechanism generally indicated at 35. A foot rest panel 36 is mounted on brackets 37 having an adjustable clamping action determined by the tightness of the screw 38 which will permit positioning of the foot rest at adjustable vertical locations. A portion 39 of the brackets 37 surrounds the legs in the manner of a collar, and tightening of the screw 38 serves to constrict the portion 39 and establish the necessary clamping action. The foot rest 36 is preferably secured to the brackets 37 by a single fastening as shown at 40 in Figure 1, so that the vertical movement of the foot rest assembly (accompanied by angular movements of the brackets 3'7 about the fastening 40 as a result of the divergence of the legs) may be freely accommodated by the radially-extending arm portions of the brackets 37 without necessity of removing or re-locating fastenings.

Conventional cross-braces are provided as shown at 41 on the front legs and 42 on the rear legs to provide added strength and to avoid over-loading the various pivot connections. The strap 43 is conventional, and is installed to prevent the infant from sliding downward and out of the chair underneath the tray 34.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by the prior art.

I claim:

1. In a folding chair having a seat, a back pivotally prising: abutment means substantially fixed with respect" to said back when said chair is in the erected condition, said abutment means being disposed to limit the rotation of said rear legs to the rear with respect to said back; and disengageable latch means for interconnecting said rear legs respectively to said abutment means when said chair is in the erected condition.

2. In a folding chair having a seat, a back pivotally connected to said seat, arm rests pivotally connected to said back, front legs pivotally connected to said seat andto said arm rests respectively, rear legs pivotally connected at the upper end thereof to said arm rests, and a link connecting each of said rear legs respectively to a member substantially fixed with respect to said back when said chair is in the erected condition, the improvement comprising: abutment means substantially fixed with respect to said back when said chair is in the erected condition, said abutment means being disposed to limit the rotation of said rear legs to the rear with respect to said back; and disengageable latch means for interconnecting said rear legs respectively to a point substantially fixed with respect to said backwhen said chair is in the erected condition.

3. In a folding chair having a seat, a back pivotally connected to said seat, arm rests pivotally connected to said back, front legs pivotally connected to said seat and to said arm rests respectively, rear legs pivotally connected at the upper end thereof to said arm rests, and a link connecting each of said rear legs respectively to a member substantially fixed with respect to said back when said chair is in the erected condition, the improvement comprising: abutment means substantially fixed with respect to said back when said chair is in the erected condition, said abutment means being disposed to limit the rotation of said rear legs with respect to said back; and disengageable latch means for interconnecting a rear leg and said abutment means when said chair is in the erected condition.

4. In a folding chair having a seat, a back pivotally connected to said seat, arm rests pivotally connected to said back, front legs pivotally connected to said seat and to said arm rests respectively, rear legs pivotally connected at the upper end thereof to said arm rests, and a link connecting each of said rear legs respectively to a member substantially fixed with respect to said back when said chair is in the erected condition, the improvement comprising: abutment means substantially fixed with respect to said back when said chair is in the erected condition, said abutment means being disposed to limit the rotation of said rear legs with respect to said back; and disengageable latch means for interconnecting a rear leg and a point substantially fixed with respect to said back when said chair is in the erected condition.

References Cited in the file of this patent UNITED STATES PATENTS 238,708 Parker Mar. 8, 1881 388,981 La Barbe Sept. 4, 1888 390,801 Parker Oct. 9, 1888 1,683,327 Bouharoun Sept. 4, 1928 2,599,164 Cudini June 3, 1952 2,652,098 Nordmark Sept. 15, 1953 2,705,043 Hoven Mar. 29, 1955

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