US1747329A - Folding chair - Google Patents

Description

Feb. 18, I930; R. B. SMITH 1,

FOLDING CHAIR Filed April 6, 1928 l/VI/E/VTOR ROBERT BIGHAM SMITH ATTORNEY Patented Feb. 18, 1930 UNITED STATES PATENT QFFICE FOLDING CHAIR Application filed April 6,

of-the-way position to permit ready access to and from the rear seat.

In such constructions now known, complicated spring actuated mechanisms are utilized for automatically folding the seat as an incident of lowering the back from its upstanding position on to the seat, but the installation of such constructions usually require mutilation of vehicle parts and are too expensive for general adoption.

The primary object of the invention is to provide a simplified form of mechanism for folding the seat into its out-of-the-way position, incidentally eliminating the known form of back actuated mechanism for folding the seat and thus provide a structure which can be formed economically, easily installed without mutilating the vehicle structure and thus provide a control for the chair which can be marketed at low cost.

Broadly, this object is obtained simply by positioning a seat folding spring beneath the seat and arranged to be controlled by the position of the back but without any physical connection between the spring and the back.

Incidentally, the invention features an extremely cheap and light type of spring which will be of insufficient strength to elevate the seat when the back is in its normal upright position, but which spring is capable of swinging the combined seat and back when the back is lowered into superposed position on the seat to reduce the leverage resistance to the spring action.

Another object of the invention is to pro Vide a latch construction controlled by the position of-the back and which will act to defeat accidental closing of the seat which might occur when the chair is-subjected to jolts as when the vehicle in which it is mounted is riding over rough grounds.

Various other objects and advantages of the invention will be in part obvious from an inspection of the accompanying drawings and in part will be more fully set forth in the following particular description of one form of 1928. Serial No. 268,070.

mechanism embodying my invention, and the invention also consists in certain new and novel features of construction and combination of parts hereinafter set forth and claimed.

In the accompanying drawing:

igure 1 is a View in side elevation of a chair constituting a preferred embodiment of the invention and with the chair in its normal usable position; and

Figure 2 is a similar view showing the chair in its folded position.

In'the showing of the chair it will be understood that the parts of the seat 10, back 11 and .connections are intended to represent conventional structures. In the drawing, the forward portion 12 of the seat 10 is pivotally mounted on the hinge connection 13 for upward and forwardly swinging movement about a forward axis 14. The seat is provided with a rear foot 15 following conventional practices in this respect. The back 11 is carried at the rear portion of the seat 10 and is supported by the hinge l6 and is designed to be swung about a rear axis 17 to and from the upstanding position shown in Fig. 1 and the collapsed position shown in Fig. 2. i 1

Positioned between the floor or other support 18 and the underside of seat 10 is a U- spring 19 but it is understood that any conventional form of spring may be utilized in this position to elevate the seat 10 from the horizontal, usable position shown in Fig. 1 into the elevated position shown in Fig. 2. An alternative suggestion is to have a coil spring forming port of the hinge connection 13, but in any case it is, of course, preferable that such form of spring be utilized as will remove or tend to remove itself from the passageway used by the person passing the elevated chair; I

It is obvious that with the back in the elevated position shown in Fig. 1, the center of mass of the chair as a whole will be adj acent the rear portion of the seat or, differently expressed, the leverage arm measured rearwardly from the axis 14% will be relatively long. Swinging the back 11 down'wardy and forwardlytowards or superposed on the seat,

will of course advance the center of mass toward the axis of rotation of the seat at 14, thus reducing the leverage arm between the new center of mass of the chair as a whole and the axis 1 1. As it is the primary intent of this disclosure to simplify and thus cheapen the parts added to the conventional chair structure, the spring 19 is designed to be weak compared to springs heretofore used for the purpose of elevating chairs. In the instant case, the spring 19 is not sufficiently powerful to elevate the chair with the back in elevated position, or differently expressed, the spring is not sufficiently strong to overcome the long leverage effect. A stop 16 limits the elevating movement of the back.

On the other hand, the spring is of sufficient strength to elevate the chair and swing it about the axis 1 1 into the position shown in Fig. 2 when the back has been lowered or, differently expressed, when the leverage efiect has been shortened. Even if the spring 19 should happen to be a little undersized and thus not sufficient to start the turning movement of the chair any slight assistance at the time the back is folded down will be sufficient to start the spring action and after the seat has once begun to turn, almost any strength of spring will be sufficient to complete the turning movement.

It is understood that the invention is complete as thus far described. It is suggested herein, however, that as an extra precaution and where additional expense is warranted, a safety latch may be employed to insure the maintenance of the seat in its operable position as shown in Fig. 1. For this purpose there is disclosed a spring latch 20, the upper end of which is formed into an angled finger guiding ledge 21, adapted to receive the finger 22 projecting'rearwardly from the back 11 and designed to engage the ledge 21 to shift the latch as a whole from the full line into the dotted line position shown in Fig. 1. Beneath the ledge 21, the latch is formed into a U-shaped crotch 23 into which the free end of the finger 22 extends.

In operation and assuming that the chair is in the position shown in Fig. 1 and that it is desired to have the seat fold automatically into an out-of-the-way position, the operator simply lowers the back 11. If it should so happen that the device is equipped with the latch illustrated, the forceful muscular effort of the operator will be sufficient to force the finger 22 out of the long engagement shown in Fig. 1. Folding the back down on top of the seat will shift the center of mass of the combined seat and back as a whole thus permitting the spring to react and fold the seat into the position shown in Fig. 2.

By means of the construction herein disclosed, it is possible to make conventional forms of folding seats in automobile structures automatic in their action, simply by installing a relatively weak spring between the seat and the floor and there is no necessity of mutilating either the seat or parts of the automobile structure in order to install this simplified chair control.

I claim:

1. A seat pivotally mounted to swing about a forward axis adjacent its forward edge, a back therefore connected adjacent its lower, rear edge to the rear portion of the seat,

mounted thereon to swing about a rear axis adjacent the rear of the seat and adapted to be folded about said rear axis forwardly and downwardly towards the top of the seat, thereby to advance the center of mass of the combined seat and back towards said forward axis and thus reduce the leverage effect thereof, and a spring acting on the seat and tending to swing the same and the superposed back forwardly about said forward axis, said spring being of a strength capable of elevating the seat and back when the back is swung forward about its axis of rotation but not of sufficient strength to elevate the seat when the back is in its normal upright position.

2. A seat pivotally mounted to swing about a forward axis adjacent its forward edge, a 1

back therefore connected adjacent its lower, rear edge to the rear portion of the seat, mounted thereon to swing about a rear axis adjacent the rear of the seat and adapted to be folded about said rear axis forwardly and downwardly towards the top of the seat, thereby to advance the center of mass of the combined seat and back towards said forward axis and thus reduce the leverage effect thereof, and a spring acting on the seat and tending to swing the same and the superposed back forwardly about said forward axis, said spring being of a strength capable of elevating the seat and back when the back is swung forward about its axis of rotation but not of sufficient strength to elevate the seat when the back is in its normal upright position, and latching means engaging the back for preventing an accidental folding of the back forwardly towards the seat.

3. A seat pivotally mounted to swing about a forward axis adjacent its forward edge, a back therefore connected adjacent its lower, rear edge to the rear portion of the seat, mounted thereon to swing about a rear axis adjacent the rear of the seat and adapted to be folded about said rear axis forwardly and downwardly towards the top of the seat, thereby to advance the center of mass of the combined seat and back towards said forward axis and thus reduce the leverage effect thereof, and a spring acting on the seat and tending to swing the same and the superposed back forwardly about said forward axis. said spring being of astrength capable of elevating the seat and back when the back is swung forward about its axis of rotation but not of sufficient strength to elevate the seat when the back is in its normal upright posit-ion, and latching means engaging the back for preventing an accidental folding of the back forwardly towards the seat, and means actuated by a forward folding movement of the back for releasing said latching means and thus permit the spring to function.

4. A chair comprising a seat pivotally mounted to swing about a forward axis a back pivoted to the seat to swing about a rear axis to and from a position superposed on top of the seat, but otherwise free of the seat and a spring acting directly on the seat to swing the combined seat and back about said forward axis, said spring controlled by the position of the back relative to the seat but physically disconnected from the back.

Signed at Macon, in the county of Bibb and State of Georgia, this 15th day of March, A. D. 1928.

ROBERT BIGHAM SMITH.

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