Improvement in Collapsable Chairs.
Year: 1899

page_text: I, FRITZ VOGEL, Merchant, of Herderstrasse 22, Düsseldorf, in the German
Empire, do hereby declare the nature of this invention to be as follows:-
This invention relates to collapsable or folding chairs provided with two pairs
of hinged legs crossing each other.
Each pair of oross legs is connected at the top by the seat and at the bottom
by a tie of any suitable material, but at the crossing the legs are not connected.
In consequence of this arrangement the seat may be placed at any desired
angle, like that of a rocking chair.
In the normal position the weight of the chair and that of the human body
are preferably concentrated over the centre of the legs. To prevent the accidental
collapse of the chair, when the person is leaning backward, two of the legs are
provided with an elastic stop-piece fixed to the same a short distance below the
crossing, so as to form a support for the other legs after the point of crossing
has been shifted a given distance.
At the bottom the legs are connected by a single tie bar or a pair of tie bars
attached to one leg by a hinge joint and secured to the other leg by a hook.
After the tie bars have been unhooked or detached, the chair will collapse and
can be easily transported.
Dated this 15th dow of Mach 1900
Improvement in Collapsable Chairs.
I, FRITZ VOGEL, Merchant, of Herderstrasse 22, Düsseldorf, in the German
Empire, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This invention relates to collapsable or folding chairs provided with two pairs
of hinged legs crossing each other.
In the accompanying drawings, Fig. 1 is a front view of a chair embodying
my invention; Fig. 2 is a side view of the same in its normal position, the seat
being horizontal; Fig. 3 is a side view showing the seat inclined backward;
and Fig. 4 shows the chair collapsed.
Each pair of cross legs m and n is pivoted at the top to a side rail o serving
to support the seat, and connected at the bottom by a tie bars of any suitable
material, but at the crossing the legs are not connected.
At the bottom the legs are connected by a pair of cross bars 9, one in front
031

page_text: and one at the back, so as to serve as pivots or hinge joints between the legs m, n,
and the tie bars s, each of which is provided at one end with an eye, and at the
opposite end with a hook, as shown by the drawing. Instead of the hooked tie
bars, one or more elastic bands or chains may be used.
In the normal position of the chair (Fig. 2), the centre of gravity of the chair
and that of the human body combined is situated approximately over the centre
of the legs.
It will be seen that a geometrical figure composed of the four sides m, n, o, »;
hinged together at the ends as described, may assume various shapes, which are
only limited by the requirement, that the upper extremity or pivot of the leg_m
must always remain on a circle having its centre in the lower pivot, that the
upper extremity of the leg must remain on another circle having its centre
in the lower pivot, and that the side o connecting the two circles must have a
constant length.
In order to perform a rocking motion with such a-chair, the person sitting on
it need only rest the feet on the floor and then lean backward and forward alter-
nately. As shown by Figs. 2 and 3, the pivot connecting the upper end of the
leg n with the side o and also with the back p (on each side of the chair) passes
through a longitudinal slot o, formed in the side rail o, and the front end of each
side rail o is connected with a point near the middle of the back p by a hinged
bar or link r.
To prevent the accidental collapse of the chair, when the person is leaning
backward, two of the legs are provided with elastic stop-pieces a (one for each
leg) fixed to the same a short distance below the crossing, so as to rest on studs
or projections of the other legs, after the point of crossing has been shifted a
given distance.
For folding such a chair, the front ends of the tie bars s are hooked out of the
cross bars the upper end of the leg n, together with the lower end of the back p,
is pressed forward in the slot o₁, until the link can be folded down upon the
side rail o.
For replacing the folded chair in its position of use, the legs m and n are first
erected and then the front ends of the tie bars 7 hooked in.
In the chair represented by the drawings, the ann rests are provided with
hinge joints b and c, which facilitates the erection and folding up of the chair.
I am aware, that it has been proposed to construct rocking chairs by means
of side frames composed of two horizontal bars and two diagonal bars pivoted to
the horizontal bars, but not connected with each other, and I do not claim this
principle broadly.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. A collapsable chair having two pairs of cross legs which are hinged at the
top and connected at the bottom by tie bars, chains, or flexible bands, and pro-
vided near the middle with elastic supports or stops a, substantially as described.
2. A collapsable chair having two pairs of cross legs m, n, hinged at the top,
but not connected in the centre, a slotted side rail o, hinged back p, and con-
necting links r, substantially as described.
3. A collapsible chair constructed and adapted to operate substantially as
described and shown by the drawings.