Improvements in Tilting Chairs or Seats.
Year: 1893

page_text: Date of Application, 1st Feb., 1893-Accepted, 11th Mar., 1893
COMPLETE SPECIFICATION.
Improvements in Tilting Chairs or Seats.
I, Dr. SIEGFRIED Czarski of 5" Karl Zeissplatz, Jena, Saxe-Weimar, in the
Empire of Germany, Director of Optical Instrument Works 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 the seats of chairs and benches the object attained by
my construction being that inclination is given to such seat or bench suited to the
bodily position for the time being of the person scated on same.
With the chairs now generally in use the seat is usually at (about) a right
angle with the legs of the chair and therefore parallel with the floor.
In consequence of this the body of the sitter is almost always in a disadvan-
tageous position especially when the sitting person is leaning forward for the
purposes of writing drawing etc. In this case the body is bent together and the
top parts of the thigh form an acute angle with the vertebral column or in some
cases a right angle the direct consequence hereof is that the organs of the lower.
part of the body especially the abdominal intestines are disturbed in their
functions.
Of the numerous complaints which are especially connected with a sedentary life
the greater portion are attributable mainly to the constant bent position of the
body of the sitter that is to say to the present unsuitable construction of the chairs
in this respect.
Attempts have already been made to remedy this evil for example in writing
chairs especially for stout persons the seats have been given a somewhat sloping
inclination from the back to front. While in the act of writing this position
indeed comfortable; it is uncomfortable however if the sitter wishes to recline
backwards on the chair as there is a tendency to slip down on the sloping seat.
The observation is also further to be made that many people in order to avoid
the discomfort arising from long sitting in a bent position tip the chair forward on
its front legs whilst others have the habit of sitting on the front edge of the chair
whilst writing.
A remedy is provided for the said evils if the chair is so constructed that the
seat at pleasure (and yielding automatically to the pressure of the thighs) changes
its position in relation to the chair legs and to the floor and is thus kept horizontal
or even made to incline somewhat backwards when a person sits back and leans
the shoulders against the back of the chair-and to slope in a sufficient measure
forwards as soon as such person bends forward to write.
This object can be obtained by various methods of mechanical constructions.
My present invention is as follows :-
The seat is mounted on hinges or pins or on a horizontal axis from left to right
of the seat so that the latter can swing or oscillate thereon and at the same time
the seat by a suitable arrangement of springs after the cessation of the pressure
upon it on one side is again brought back to its original or normal position. The
Oscillation or movement of the seat may be upon a transverse rod serving as an
axis or upon two pirota fixed above or underneath it on the right and left.
The seat can either move wholly inside the side bearers or these must be
arranged in such a manner as to allow the movement of the soat.
Referring to the accompanying drawings :—
Fig. 1 shows the seat on au incline, and Fig. 2 in a horizontal position.
In the said drawings a chair is represented in which the seat turns upon two
nivots the hearers of which L. L. are fixed inside the sides of the chair frame
Aa

page_text: the pivots or axes Z Z are at the same height as the seat they are almost hidden
thereby. In this case the seat moves between the side frames.
Upon the front side of the seat the wooden moulding serves as a rest for the
two strong spiral springs W whilst the other ends of the springs act against the
bottom of the seat.
Two curved iron rods are fixed underneath the seat and pass freely through the
springs as shown. The amount of variation of the incline which can be imparted
to the soat is limited by the projecting attachment A.
In order on the one hand to conceal as far as possible the spring mechanism and
on the other hand to prevent the clothes or skin of the sitter being caught between
the seat and frame in bending over-it is advantageous to give to the front part
of the seat a rounded off curved form with a slight continuation of the seat frame
underucath.
The above described construction can also be advantageously and satisfactorily
employed with stuffed chairs or benches.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :--
A tilting chair or the like consisting of the combination with an ordinary chair
frame or the like support of a seat arranged and mounted and tilting on pivots or
centres on the same level as the said seat a descending part on the front of auch
seat and a spring or springs monntod beneath the said seat (at the front) arranged
combined and acting substantially in the manner and for the purposes hereinbefore
Bet forth.
Dated this 1st day of February 1805.
TONGUE & BIRKBECK,
34, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.