US2676645A - Folding chair with tablet arm - Google Patents

Description

April 27, 1954 A; F. suPn'A FOLDING CHAIR WITH TABLET ARM 2 Sheets- Sheet 1 Filed May 16, 1952 INVENTOR. 90 map/4 EJz/Pmq v ArrOE/VEYS April 27, 1954 suPrr 2,676,645

FOLDING CHAIR WITH TABLET ARM Filed May 16, 1952 '2 Sheets-Sheet 2 INVENTOR. Ham/ H F fu m Arraewe' Y5 Patented 'Apr. 2?, i954 UNITED STATES PATENT OFFICE FOLDING CHAIR WITH TABLET ARM .Adolph F- Supita, Green Bay, Wis., assignorto Norcor Manufacturing Company, Inc., Green Bay, Wis., a corporation of Wisconsin Application May 16, 1952, Serial No. 288,130- 3Claims. (o 155 125) This invention relates to a folding chair with tablet arm. 6

A primary feature of the invention consists in the arrangement whereby the chair legs and seat and tablet arm are all interconnected in such a way that the folding of the seat will mechanically affect the folding of the legs and tablet arm without requiring separate manipulation of the latter. In conventional folding chairs having tablet arms, it has been necessary to manipulate separately the support for the tablet arm in order to permit the arm to be folded. In the present arrangement, the fulcrum and linkage are so connected from the seat to the rear legs and from the seat to the tablet arm that when the seat is positioned for use, the rear legs are rigidly maintained in bracing position and the tablet arm is rigidly supported. Yet, when the seat is folded upon its pivotal connection with the main frame, its final movement automatically draws inwardly the rear or bracing legs and draws the tablet arm downwardly to folded position.

In the drawings:

Fig. 1 is a view showing my improved chair in plan.

Fig. 2 shows my chair in front elevation.

Fig. 3 is a view in side elevation of the chair shown in Figs. 1 and 2.

Fig. 4 is a view in side elevation showing the parts in process of being folded.

Fig. 5 is a View in side elevation of the completely folded chair.

The chair is of the type in which the main frame 6 comprises laterally spaced members 1 and 8 which provide the forward legs for the chair and also extend upwardly above the seat to support the back rest 9. The side members of the'main frame are cross-connected by the transverse members lil and II The rear legs are provided by a sub-frame at If comprising uprights l3 connected by cross members l4, I5. The uprights I 3 are pivoted at it to clamps I1 mounted on the main frame members i and 8. As thus far described, the structure is quite conventional. It is also conventional for the seat 20 to be pivoted between the members 1 and 3 of the main frame on pintles 2| for movement between the folded position in which the seat 29 is shown in dotted lines in Fig. 5 and the position of use in which the seat is shown in Figs. 1 to 3.

Beneath the seat there are re-enforcing flanges 22 extending forwardly and rearwardly along the side margins of the seat. Pivotally connected to these flanges near the rear of the seat are the links 23 which are desirably curved as best shown inFigs. 3 and 4. Rivets 24 may be used as pintles to provide the pivotal connection between the links and the seat. The links 23 are also pivoted by means of rivets or the like at 25 to the side members l3 of the sub-frame I2. With the seat in a generally horizontal position for use as shown in Fig. 3, the flanges 22 may rest on the transverse member ID of the main frame *6, the links 23 holding the sub-frame in a position to brace the main frame and, at the same time, tending to hold the seat securely against displacement under the weight of a user. 1

The tablet arm 39, which may have the usual shape in plan, as best shown in Fig. 1, has a fitting 3l pivotally connected by a rivet or the like at 32 with the side members I of the main frame 6 to support the tablet arm at a level convenient for use. Near its forward end the tablet arm is connected with one leaf of a hinge 33, the other leaf of which is connected with a rigid supporting post 34 which may be formed in one piece with rock shaft 35. Ears at 36 connected with the reenforcing flanges 22 of the. seat, are provided with bearing collars at 31 in which the rock shaft 35 is mounted to oscillate.

It will be observed that the supporting arm orpost 34 extends forwardly as well as upwardly from the rock shaft when the chair is openedi for use; as shown in Fig. 3. The geometry of the. chair is important to the result, the distances between the very centers of pivotal movement being such that the parts can move freely from the position of use shown in Fig. 3 through the intermediate position of Fig. 4 to the fully folded position ofFig. 5. When it is desired to fold the chair, the operator has only to lift the seat 29 with respect to the main frame 6. The initial upward movement of the seat will necessarily raise the tablet arm 30; The tablet arm will continue to move upwardly with the seat until the supporting arm or post 34 is in line with the seat. Beyond this point, the continued upward folding movement of the seat will cause a lowering, instead of a raising, of the tablet arm, as shown in Fig. 4.

Mea'ntima'the rear end of the seat has moved fromits initial position above th connecting links 23 to a position below the links as shown in Fig. 4. The continued folding movement of the seat beyond this point effects an inward movement of the sub-frame l2 toward the main frame 6. In the final position of the parts, as shown in Fig. 5, the sub-frame I2 is completely collapsed upon the main frame, in immediate proximity thereto, and the tablet arm 30 is also collapsed upon the main frame into approximate parallelism therewith.

It will be observed that there is a double toggle link action between the seat and the tablet arm support 34 and between the seat and its own sub-frame connecting linkage 23. In both cases, the Opening and folding movement of the seat requires the seat to move across dead center with respect to the associated tablet arm support 34 and the links 23. When th seat is positioned for use, its rear end is engaged in the cross brace i l of sub-frame l2 which provides the rear legs, the cross brace havin the form of a shallow channel as shown in Fig. 3. As the seat is moved pivotally toward closed position, the toggle lever relationship between the seat and the links 23 requires a slight increase ofspacing between the seat pivot 2| and the link pivots 25. As a result, the sub-frame l2 must move slightly to the rear, thereby removing cross brace M from the path of movement of the seat. In an intermediate position of the parts the several pivots 25, 24, and 2| will be aligned and thereafter the continued folding movement of the seat will draw the sub-frame inwardly.

Similarly, with respect to the tablet arm, it will be necessary for the arm to move upwardly until the pintle of hinge 33 and the axis of oscillation of the rock shaft 35 and the seat pintle 2| are all aligned in the same plane. Thereafter, continued folding movement of the seat will bring the tablet arm downwardly instead of forcing it upwardly.

The fitting 3| at the rear of the tablet arm supports the tablet arm in a position offset from the pintle rivet 32, the offset corresponding to the space required by the tablet arm support post 34 in the folded position of the parts shown in Fig. 5.

As a result of this structure, the chair folds and opens with the greatest ease and smoothness and is extremely stable in use and extremely compact when folded. The seat itself is the only part which needs be manipulated either in the opening or the folding of the chair, since it transmits motion to the sub-frame and the tablet arm and, in the open position of use, it holds these parts securely fixed in their proper relative positions.

I claim:

1. In a folding chair of the type comprising a foldable frame provided with legs, the combination with such frame, of a seat having a pivotal connection with the frame and movable on such pivotal connection from a position of use upwardly to a position of storage substantially parallel .to said frame, said frame havin seat engageable stop means defining said position of use, a tablet arm having a pivotal connection with the frame and movable on such connection from a generally horizontal position of use to a depending storage position substantially parallel to said frame, and a support having a pivotal connection with a forward portion of the seat and laterally offset to clear the side thereof and extending upwardly and. pivotally connected with the tablet arm at a point remote from the pivotal connection of such arm with the frame, said arm being displaced upwardly in the initial folding movement of the seat and downwardly in the final seat movement, the pivotal connection of the seat and support crossing a line drawn from the frame-connection of the seat to the tablet arm-connection of the support as the seat is moved between storage and use positions.

2. A folding chair comprising a main frame providing forward legs and extending thence upwardly and rearwardly, a sub-frame providing rear legs and extending upwardly therefrom in bracing relationship to the main frame and having adjacent its upper end. a pivotal connection with the main frame, a seat pivoted intermedite its ends to the'main frame and movable upon its pivot between a position of use and a position of substantial parallelism with the main frame, stop means engaged in the opening of the seat to define said position of use, a tablet arm havin a pivotal connection with an upper portion of the main frame and movable between a storage position in which it is nearly parallel to the main frame and a position of use in which it extends forwardly from the main frame above the level of the seat, and a support pivotally connected with a forward portion of the seat and extending beside the seat upwardly and forwardly and having a pivotal connection at its upper end with a forward portion of the tablet arm, whereby the tablet arm is rigidly supported from the seat when the latter is in its position of use, the initial movement of the seat from its said position of use toward its storage position bein adapted to move the tablet arm upwardly until the pivotal connection between the tablet arm support and the seat crosses a line drawn from the pivotal connection of the seat with the main frame to the pivotal connection of the support with the tablet arm, continued movement of the seat toward its storage position thereupon transmitting through said support a downward swinging movement to the tablet arm until the seat and the tablet arm are nearly parallel in their respective storage positions, the pivotal connection of the support with the tablet arm being then below the pivotal connection of the seat with said main frame by the distance by which the length of said support exceeds the distance between the point of connection of the support with the seat and the pivotal connection of the seat with said main frame.

3. The device of claim 2 in which the tablet arm is provided with a fitting providing the pivotal connection between the arm and main frame and offsetting the tablet arm from said pivotal connection by a distance sufficient to accommodate the tablet arm support in the aforesaid storage position of the seat, whereby the support lies between the main frame and the tablet arm and in approximate parallelism with both in said storage position.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,864,? 50 Moore June 23, 1932 2,452,182 Clawson Oct. 26, 1948

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