IMPROVE- MENTS IN CHAIRS AND OTHER SEATS, TABLES, OR OTHER SURFACES OR ARTICLES THE HEIGHTS OF WHICH MAY BE VARIED
Year: 1876

page_text: LETTERS PATENT to Charles Wadman, of No. 5, James Street, in the City of
Bath and County of Somerset,. Manufacturer, for, the Invention of "IMPROVE-
MENTS IN CHAIRS AND OTHER SEATS, TABLES, OR OTHER SURFACES OR ARTICLES
THE HEIGHTS OF WHICH MAY BE VARIED."
· Sealed the 27th June 1876, and dated the 25th April 1876.
PROVISIONAL SPECIFICATION left by the said Charles Wadman at the Office
of the Commissioners of Patents on the 25th April 1876.
CHARLES WADMAN, of No. 5, James Street, in the City of Bath and County of
Somerset, Manufacturer. IMPROVEMENTS IN CHAIRS AND OTHER SEATS, TABLES,
OR OTHER SURFACES OR ARTICLES THE HEIGHTS OF WHICH MAY BE VARIED."
The object of the Invention is to afford facility for readily raising or lowering the
surface of the seat, the table, or other object the height of which it may be
desirable to have capability of variation.
For this purpose I form the leg or legs or other upright supports each in two
parts, one with a toothed rack to be taken into by a pinion carried by the other
part and held from back motion by a stop kept in position by a spring. On raising
the seat or surface or other object the rack or racks will simply cause the pinion or
pinions to rotate in one direction, and the stops will prevent their return until those
stops are released by overcoming the spring pressure thereon. Several such legs or
uprights may be operated simultaneously by the respective pinions being applied to
connected gearing and shafts, and the stops may be similarly connected. In some
cases spring stops may act directly in the teeth of ratchets, so as to come into action
by the force of the springs employed, and be released as required.
The improvements apply to chairs and other seats, music stools or seats, tables,
shelves, music stands, bedsteads, cornice poles, screens, and other objects or surfaces.
•
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Wadman in the Great Seal Patent Office on the 20th October
1876.
CHARLES WADMAN, of No. 5, James Street, in the City of Bath and County of
Somerset, Manufacturer. "IMPROVEMENTS IN CHAIRS AND OTHER SEATS, TABLES;
OR OTHER SURFACES OR ARTICLES THE HEIGHTS OF WHICH MAY BE VARIED.” „
The object of the Invention is to afford facility for readily raising or lowering the
[Price 6d.]

page_text: surface of the seat, the table, or other object the height of which it may be desirable
to have capability of variation.
For this purpose I form the leg or legs or other upright supports each in two
parts, one with a toothed rack to be taken into by a pinion carried by the other
part and held from back motion by a stop kept in position by a spring. On raising
the seat or surface or other object the rack or racks will simply cause the pinion or
pinions to rotate in one direction, and the stops will prevent their return until those
stops are released by overcoming the spring pressure thereon. Several such legs or
uprights may be operated simultaneously by the respective pinions being applied
to connected gearing and shafts, and the stops may be similarly connected. In
some cases spring stops may act directly in the teeth of ratchets so as to come into
action by the force of the springs employed, and be released as required.
In order that the Invention may be more fully understood, I have annexed here-
unto Drawings in illustration of the same, which I will now proceed to explain.
Figure 1 shews by a sectional side view one arrangement of my improvements
applied to a music stool; Figures 2 and 3 shew by side view and plan view parts
thereof separately to a full size scale. In each of these views the same letters
apply to corresponding parts.
a, a, represent the ordinary legs of the stool attached to the upper frame b, and
c is the seat, which is separate from the parts a and b to admit of variation of the
height thereof, as is well understood; d is the central stem by which the seat c is
supported; this central stem d is formed at its upper end with a flange d¹ by
which it is screwed to the seat c, and on one side surface thereof it is formed with
teeth d². e is a socket formed to receive the stem d so that the stem may slide
therein in a vertical direction, and this socket e is enclosed by any suitable and it
may be ornamental part of the stool f, and this part f may be held steadily by
connecting pieces g therefrom to the legs. The socket e is also formed with a
groove in one of its side surfaces to admit of the free vertical sliding therein of the
rack or series of teeth d. A part formed on this socket also carries the axis of the
pinion h, the teeth of which on one side take into the teeth of the rack d² to hold
the stem d and consequently the seat c in any desired position, whilst the teeth
for the time on the opposite or outer side of the pinion are borne upon by the
hinged stop piece i. This stop piece i is hinged at ¹, so that whilst by bearing
on one of the teeth of the pinion it enables the pinion to resist downward
pressure applied on the seat c, it yet admits of the pinion turning freely in the
opposite direction in the upward motion of the stem when lifting the seat c. In
order to release the teeth of the pinion h from the holding by the stop i for the
descent of the seat c, there is attached to that stop i the sliding rod j, one end of
which passes through a slotted opening formed for it in the stop i, and is there
formed into a T head, so that when the outer end j¹ of that rod is drawn upon it
may draw the stop i from the teeth of the pinion h, when that pinion will freely
revolve in either direction and the scat c may be lowered as required. The rod j
is guided by passing through guides, k, and it is acted upon by a spring / with a
tendency to bear it inwards, and so keep the stop acting on the pinion . m is a
spring applied in the socket e to bear against the end of the stem d to prevent
the sudden descent of that stem with the seat on the release of the pinion h. If
desired, in place of one, a central stem d and parts acting therewith, there may be
two or more such stems and parts, and the pinions of each pair may be applied to
one axle capable of being operated by a fixed handle or a loose key, or, as in the
case of four of such stems being employed, the two axles thereof may be connected
together by a cross or other shaft and bevilled gear.
Figure 4 shews by sectional side view, and Figure 5 by plan view, a slight
modification of the above in which the form of the tecth d is somewhat altered,

page_text: and in place of employing a pinion h the inner end of the rod j is borne against
those teeth to act as the required stop. Figures 6 and 7 shew parts of this arrange-
ment on a larger scale. Figures 8 and 9 shew this arrangement applied to a stool
having two supporting stems d, with the stop rod j formed so that its opposite
ends act in the teeth of the respective stems, and it is acted upon to keep those
ends in position by a spring 1 whilst those ends may be withdrawn by the stem ².
It will readily be understood that the improvements are applicable to the legs
of chairs and other seats and of tables, the stems of music stands, of screens, the
shelves of dinner waggons and other shelves, the pillars of bedsteads, supports for
cornice poles, and to other objects or surfaces.
Having thus described my Invention and means which I adopt in carrying the.
same into effect, I would have it understood that what I claim is the arranging
or combining parts by which facility is afforded for adjustment of the height of
chairs and other seats, tables, and other surfaces or articles as described.
In witness whereof, I, the said Charles Wadman, have hereunto set my hand
and seal, this Nineteenth day of October, in the year of our Lord One thou-
sand eight hundred and seventy-six.
CHARLES WADMAN.
(L.S.)