IMPROVEMENTS IN PIANO CHAIRS
Year: 1886

page_text: Date of Application, 27th Apr., 1886.
Complete Left, 23rd Feb., 1887.
Complete Accepted, 25th Mar., 1887.
I CARL LUCKAT of Berlin (Lausitzerstrasse 10) in the German Empire Manu-
facturer do hereby declare the nature of said invention for "IMPROVEMENTS IN PIANO
CHAIRS to be as follows:-
These improvements have reference to an application of adjustable seat to chairs or
music stools for pianoforte players or for players of similar instruments.
At the back part of the seat of the chair are fixed two bars so as to project down-
wards. These two bars are carried in guides fixed to the back framing or legs of the
chair so as to be readily moved up and therein. The guides are formed with or have
fixed to them each a toothed rack in which a pawl acted on by a spring is kept
engaged. The pawls are mounted at the two ends of a cross bar which is carried in
the two sliding bars and thus extends across the back part of the chair. It may be
turned by hand so as to force the pawls against the resistance of the springs out of
the teeth of the racks and when this is done the seat may be readily moved up or
down. When the cross bar is released the pawls again engage in the teeth of the
racks and fix the seat in position for the player.
100
CAPITAINE & VON HERTLING,
89, Chancery Lane, London, W.C.,
Agents for the Applicant.

page_text: I, CARL LUCKAT of Berlin (Lausitzerstrasse 10) in the German Empire, Manu-
facturer, do hereby declare the nature of said invention for "IMPROVEMENTS IN PIANO
CHAIRS and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
These improvements have reference to a construction of chair with adjustable seat
intended chiefly, but not solely, for pianoforte players or for players of similar
instruments.
Referring to the accompanying drawings
Figs. 1 and 2 are respectively a back and side view of a portion of a chair of this
invention. Figs. 3 and 4 and Figs. 5 and 6 are similar views shewing the invention
applied in two, other somewhat different forms. Fig. 7, shews a chair of this invention
in perspective with the seat raised. The remaining figures refer to details.
which
a is a hollow rail of cast iron which is let into each of the two back supporis of the
chair and the form of which is shown in Figs. 1 and 1. In Figs. 1, 3, and 5 the
rail a is left out on the right hand side. In the rails a are carried the bars
are firmly connected to the seat of the chair and bear against the seating formed by
the parts of the rails a. They are connected together at top by two rods c.
Between these two latter is mounted a mechanism for fixing the seat in any desired
position; it consists of two levers d, spring e and levers. The levers & may turn
on pins d', and their inner ends are jointed to a handle whilst their outer ends
which reach through slots one in each of the bars b-carry peculiarly formed
levers so as to be capable of turning thereon. The inner ends of the two levers d
are kept constantly pressed downwards by the powerful spring e the outer ends with
the levers being thereby forced upwards. At the upper end of each of the two
bars is a wedge shaped lug the oblique surface of the same being directed towards
the levers The action of the spring e tends to force these latter upwards and to
press with their long arm against the lugs whereupon they are turned on their
pivotting point in the direction shewn by the arrow in Fig. 8. By reason of this
turning movement their shorter arm is pressed against the inner surface of the rails a
with great force thereby fixing and holding in them the bars b.
The mechanism operates as follows:-
h
When it is desired to move the seat i of the chair and bring it to a higher or lower
position the handle g is pressed upwards when the pressure exercised by the spring e
on the inner end of each of the levers d is overcome and the ends carrying the levers f
descend. Upon this the shorter arm of each of the two levers ceases to bear against
the rails a and the bars & may then be freely moved up and down within the same,
and consequently with them also the seat i. When the upward pressure is withdrawn
from the handle g the spring e again comes into action and the short arms of the
levers again draw the bars 6 tight against the inner surface of the rails a. Figs. 3
and 4 shew a modification of the arresting mechanism. In this case also a are two

page_text: rails (one of which only is shewn) let into the two back supports; their inner or
hollow part is provided with teeth as shown in Figs. 2ª, 2, 2°. These are engaged
in each rail a by a pawl acted on by a spring and are in connection with the seat i.
They are mounted on the ends of a square bar passed through the sleeve m.. When
the seat is to be moved the sleeve mis turned in the direction of the arrow (Fig. 9)
then the pawl disengages from the teeth and the seat may be slid up or down. On
the sleeve m being released, the spring & presses the pawl 1 back again into the teeth
and so fixes the seat i.
Figs. 5 and 6 shew a further modification of the arresting mechanism.
The rails are provided interiorly with teeth in which the pawls or catch parts o
acted on by the springs n engage. The form of the rails a may be seen in Figs. 3,
3° and that of the pawls o in Fig. 3. is a disc (Fig. 5) mounted between two
rods e so that it may be turned. The disc p has a segment cut away from it, or is
provided with a segmental recess. To the disc are jointed two rods, which
engage or connect with two pins or hooks s one on each inner end of the catch teeth
parts o. If now the recessed disc p is turned in the direction of the arrow (Fig. 5)
the catch parts o are, through the rods r, drawn out of the engaged position in the
teeth of the rails a and the bars & may then be freely moved therein, carrying with
them the seat i. Upon the recessed disc p being turned the springs n are brought
into tension, but as soon as the handle is released they bring the two catch parts o
into engagement with the teeth and the recessed disc P back again to its previous
position. This latter is turned by pressing the handle g in the direction of the arrow,
the handle being mounted so as to turn on a joint between the two rods c.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :
In a chair with adjustable seat :-
1. The arrangement of the rails a inserted in the back legs of the chair in which
the sliding bars are carried, and of a vertical adjustable two arm lever of turning on
a joint, in combination with a wedge shaped lug 4, in such manner that the lever
when it is moved against the oblique wedge surface turns on its joint, its shorter arm
being pressed against the inner surface of a rail a thereby fixing the seat of the chair
in the desired position substantially as described and shewn.
2. For the vertical up and down movement of the lever the arrangement of the
lever turning on a pivot one end of which lever is normally kept pressed down by
the spring e whilst the other end of the same moves the lever against the oblique
surface of the lug h, substantially as described and shewn.
3. The arrangement in the hollow rails a of teeth in which pawls acted upon by
springs engage, and so fix the seat of the chair in combination with the square bar
passing through the sleeve m and on which the pawls are mounted for the purpose
specified substantially as shewn and described.
4. The arrangement of recessed disc p with draw rods and catches o which latter
are pressed by the springs so as to engage in the teeth of the hollow rails a, and
withdrawn therefrom by turning the recessed disc p through the handle e, for the
purpose of adjusting the height of the seat substantially as described and shewn.
Dated this 23rd day of February 1887.
CAPITAINE & VON HERTLING,
89, Chancery Lane, London, W.C.,
Agents for the Inventor.