US2709482A

US2709482A - Folding arm chair

Info

Publication number: US2709482A
Application number: US308769A
Authority: US
Inventors: Schlaak Ervin
Original assignee: DURHAM Manufacturing CORP
Current assignee: DURHAM Manufacturing CORP
Priority date: 1952-09-10
Filing date: 1952-09-10
Publication date: 1955-05-31
Anticipated expiration: 1972-05-31

Description

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.Mw EL w55' la. smmm FOLDING MM CHAR Filed Sept. l0, 3.952

FOLDING ARM CHAIR Ervin Schlank, Muncie, Ind., assiguor to Durham Manufacturing Corporation, Muncie, Ind., a corporation of indiana Application September 10, 1952, Serial No. 308,769

7 claims. (ci. 15s- 142) This invention relates to an improvement in folding arm chairs and specifically to the provision of a novel arm-rest unit in such chairs embodying novel and smoothly acting automatic mechanism controlling the folding and unfolding action of such unit in synchronism with the action of the chair.

The primary object of my invention is to provide, in a folding chair structure, an extremely rigid arm-rest unit of such design that its incorporation in a conventional folding chair structure will add rigidity to the structure as a whole.

A further object is to provide appropriate linkage associated with the arm-rest unit whereby the unit will be moved to a folded position when the chair is moved from an unfolded or use condition to a folded condition.

Another object is to provide an arm-rest unit which, while possessing the aforementioned characteristics, is of such design as to lend itself readily to relatively simple and easy manufacture.

Further objects of the invention will become apparent as the description proceeds.

To the accomplishment of the above and related ob- 'ects, my invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that change may be made in the specific construction illustrated and described, so long as the scope of the appended claims is not violated.

Fig. l is a side elevation of a chair embodying my invention;

Fig. 2 is a front elevation of the chair as viewed from the right of Fig. l;

Fig. 3 is a perspective View of the chair ot' Fig. l shown in partially folded condition; and

Fig. 4 is a fragmental perspective View similar to Fig. 3 but showing the chair in its completely folded condition.

Referring more particularly to the drawings, a chair comprises a front leg unit F comprising

front legs

11 and 12 and a back-rest extension 13. In the illustrated embodiment, this front leg unit takes the form of an integral, inverted U-shaped element, the opposite sides of the element constituting the

legs

11 and 12 and the end a base 1dof the element F, in conjunction with a web 15, constituting the chair back-rest. A cross bar 19 spans the lower portions of

legs

11 and 12 to increase the rigidity of the structure.

A back-leg unit B comprises back

legs

16 and 17. A cross bar 18 spans the lower portion of said legs to lend rigidity to the structure.

A seat element A is disposed between the legs of units F and B and is pivotally connected to

front legs

11 and 12 at

points

20 and 21 respectively, and is pivotally connected to

back legs

16 and 17 at

points

22 and 23 respectively, whereby the units F and B are tied together in an operative structure.

A link 24 is pivotally connected at 25 to front leg 1i 2,709,482 liatented May 31, 1955 and at 26 to back leg i6, both points 25 and 2o being above the pivotal connections between the seat and the respective legs. A similar link 27 is similarly pivotally connected to front leg l2 and back leg 17.

As may be clearly seen from an inspection of Fig. l, in the unfolded or use position of chair 10, front-leg unit F inclines rearwardly from the vertical and backleg unit B inclines forwardly from the vertical, and the free upper ends of the

back legs

16 and 17 abut the

front legs

11 and 12 respectively.

The chair thus far described constitutes a well known structure in the art. It is with this or a chair of similar construction that my invention is most advantageously adapted substantially in the manner now to be described.

A generally U--shaped arm-rest unit l, comprising a base 38 and a substantially parallel pair of

arms

23 and 29 is arranged on chair l@ so as to straddle the backrest extension 13 of front-leg unit F and is pivotally connected thereto at points 3l) and 3l lying in a common axis substantially normal to the median plane through chair 1li. A portion 32 of arm 28 extends rearwardly from point Titi and a similar portion 36 of arm 29 extends rearwardly from point lll.

A link 33 has one end pivotally connected to portion 32 and the other end pivotally connected to link 24 at point 3S intermediate pivotal points Z5 and 26. A similar link 37 has one end pivotally connected to portion 36 and the other end pivotally connected to link 27 intermediate its ends.

Preferably, links 33 and 3'/ are of such length as to hold

arms

27 and 28 in substantial parallelism with seat A and are connected respectively to links 24 and 27 in a manner such that

arms

23 and 29 will maintain substantial parallelism with seat A in moving between the folded and unfolded positions of chair 10.

As clearly seen from an inspection of Figs. 3 and 4, as seat A is swung about

pivot points

20 and 21,

back legs

16 and 17 will, under the influence of

links

24 and 27, be swung into substantially parallel juxtaposition with front legs 11 and l2. At the same time,

links

33 and 37 will be shifted axially downwardly (as viewed in Fig. 3) thereby swinging the arm-rest unit R counterclockwise about pivot points 3ft and 3i. Because of the arrangement of

links

33 and 37 in relation to

links

24 and 27, arms 2% and 29 will maintain a substantially parallel attitude relative to seat element A throughout the swing between their use position and their folded position.

While the mechanism thus described is relatively simple in its operation and inexpensive in its manufacture, its incorporation in a chair structure of this or similar type converts the chair from one of limited utility to one of greatly increased utility and comfort; and the particular construction of the unit R and of its associated linkage is such as not only to provide rigidity in the unit itself but also to lend added rigidity to the conventional chair structure with which said unit is associated.

I claim as my invention:

l. In a folding chair of the type comprising a front leg unit including a back rest extension, a back leg unit, a seat element pivotally connected to said front leg unit and pivotally connected to said back leg unit, and link means pivotally connected to said front leg unit and to said back leg unit above said seat, said back leg unit and said front leg unit being otherwise unconnected, the iuvention which comprises a rigid arm-rest unit comprising a base portion and a pair of substantially parallel arms, said arms straddling the back rest extension of said front leg unit and being pivotally connected thereto, with said base portion located behind said back rest extension and spanning the same, and means operatively associated with said arm-rest unit to cause said unit to ascenso 2. The device of claim 1 in which said lastnamed` means comprises supplemental link means having one end pivotally connected to said first-named link means at a point intermediate the points of connection with said respective leg units, said supplemental link means being pivotally connected at its other end to said arm-rest unit between the base portion thereof and the pivotal connection thereof with said back rest extension.

3. In a folding chair of the type comprising a front leg unit including a back rest extension, a back leg unit, a seat element pivotally connectedv to said front leg unit and pivotally'connccted to said back leg unit, and link means at eachy side of said chair pivotaliy connected to said front leg unit and to said back leg unit above said seat, said front leg unit and said back leg unit being otherwise unconnected, the invention which comprises a rigid arm-rest unit comprising a' base portion and a pair of substantially parallel arms, said arms straddling the back rest extension of said front leg unit with each arm pivotally connected thereto for oscillation about a common axis substantially normal to the median plane of said chair, with said base portion located behind said back rest extension and spanning the same, and a pair of supplemental link means each having one end pivotally connected to one of said tiret-named link means at points intermediate the points of connection thereof with said respective leg units, each of said supplemental link means beingv pivotally connected, at its other end, to its respective arm between the base portion of said arm-rest unit and the pivotal connection of such arm with said back rest extension.

4. in a folding chair ot' 'the type comprising a front leg unit including a back rest extension, a back leg unit, a seat element pivotally connected to said front leg unit and pivotally connected to said back leg unit, and a pair of links, one on each side of said chair with its opposite ends pivotally connected respectively to said front leg unit and to said back leg unit above said seat, said front leg unit and said back leg unit being otherwise unconnected, the invention which comprises a rigid arm-rest unit `comprising a substantially U-shaped element, the opposite legs of said element straddling the back rest extension of said front leg unit with each pivotally connected thereto for oscillation about a common axis substantially normal to the median plane of' said chair and with the basey portion of said U-shaped element located behind said backest extension and spanning the same, and a pair of supplemental links each having one end pivotaliy connected to one of said iirst named links intermediate the points of connection thereof with said respective leg units, each of said supplemental links being pivotaily connected at its other end to the adjacent leg of said U-shaped element between the hase portion of said element and the pivotal connection thereof with said back-rest extension.

5. ln a folding chair of the type comprising a front leg unit including a back rest extension, a back leg unit, a seat element pivot-ally connected to said front leg unit and pivotally connected to said back leg unit, and link means pivotally connected to said front leg unit and to said back leg unit above said seat, said front leg unit and said back ieg unit being otherwise unconnected, the invention which comprises a foldable arm rest unit coniprising an arm pivotally connected to said back-rest extension above said seat for oscillation about an axis A substantially normal to the median plane of said chair and extending, when in use position, forwardly and rearwardly beyond said back-rest extension, and supplemental link means having one end pivotally connected to said first-named link means at a point intermediate the points of connection thereof with said respective leg units, said supplemental link means being pivotaliy connected, at its other end, to said arm between the rcarmost end of said and the pivotal connection thereof with said bz ik rest extension.

6. The device of claim 5 in which there are two such arm and supplemental link assemblies, one on each side oi said chair and including a base portion rigidly xed at each end thereof to the rearmost end of one of said arms, said base portion spanning said back-rest exten sion behind said extension.

7. The device 0E claim 6 in which said two arms and said base portion constitute an integral U-shaped element formed of a single piece of material having its opposite ends bent out of the common axis of said piece into substantial parallelism substantially normal to said common axis.

References Cited in the tile of this patent UNITED STATES PATENTS