IMPROVEMENTS IN CONVERTABLE SCHOOL-DESKS
Year: 1886

page_text: We HENRY ADDISON and SAMUEL ADDISON both of Gnosall, Stafford School
Furniture Manufactures do hereby declare the nature of our invention for
"IMPROVEMENTS IN CONVERTABLE SCHOOL-DESKS" and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement:-
Our invention has for its object improvements in School Desks which we call
the "Automatic Convertable School Desk" which can be converted from a writing
desk to form a back to the seat immediately before it in a simple and effective
way while the inclination of the desk for writing can readily be arranged at any
desired angle. Our invention can be applied to the Dual or Desks of any length
and is so easily manipulated that a single person could convert a number of deska
into backs or backs into desks in a few seconds. A desk made according to our
invention has an iron semi circle at the top and forming part of the iron standard
to the centre of which is fixed a spindle upon which an arm supporting the desk
or back revolves and slides along while the arm is kept against the semi circle by
a spiral spring encircling the spindle and thereby forcing a projection on the arm
into a notch in the semi circle and rigidly securing the desk in the required position
only to be moved by pressing against the end of the desk and thereby forcing the
arm back a sufficient distance for the projections on it to be clear of the notch in
the semi circle.
In order that our invention may be clearly understood and more easily carried
into practice we have appended hereunto a sheet of drawings showing a desk made
according to our invention and by the help of which we shall better ascertain the
nature thereof and in what manner it may be performed.
Figure 1 is an end elevation of a desk in position for writing the dotted lines
showing position of same when forming a back.
Figure 2 is a front elevation of the desk in the position shown by Figure 1 and
Figure 3 is a back elevation showing the desk forming a back as shown by the
dotted lines in Figure 1 and is represented with the arm pressed away from the
segment a sufficient distance to allow the desk to revolve.
Upon the cast iron standard B and forming part of it is the semi circle O to the
centre of which is fixed the spindle D and upon this spindle the arm E to which
the desk F is fixed turns and slides the arm having the projection e¹ which fits

page_text: into either of the notches c². c³ or c³ as the case may be the spiral spring G prevents
it from slipping out and thereby keeps the desk in its place. For converting the
desk F into a back rest as shown by Figure 3 or vice versa the desk would be
pressed in the direction of the arrow K in Figure 1 until far enough for the
projection e¹ to clear the notch c* when the desk would turn upon the centre d¹
until it rests against the shelf H as shown by dotted lines on Figure 1. It will
readily be seen that by providing notches all round the semi circle C the desk
could instantly be fixed at any desired angle. Upon the desk F we screw an iron
plate f¹ leaving a space between it and the wood to form a slate rack inclining the
slot so that the bottom of the slate J would rest on the shelf H at h¹. We may
cover up the spiral spring G with a case and might form a guard to prevent fingers
being pinched between the arm E and the semi circle O and if required to bolt or
lock to prevent the inclination of the desk being altered when not necessary.
Having now particularly described and ascertained the nature of our said
invention and in what the same is to be performed we declare that what we
claim is :-
The improvements in convertable School Desks which are provided with
standards having notches into which the top F takes so as to be adjustable to
any desired angle and to form a back rest the conversion being accomplished by
pressing the desk end wise against the spring G substantially as herein set forth.
D
GEORGE BARKER,
Agent for Applicants.