IMPROVEMENTS IN THE MECHANICAL MEANS OF VARYING THE HEIGHT OF SEATS, TABLES, AND OTHER ARTICLES
Year: 1877

page_text: LETTERS PATENT to William Dawes, of Kingston Grove, Leeds, in the County
of York, Engineer, for the Invention of "IMPROVEMENTS IN THE MECHANICAL
MEANS OF VARYING THE HEIGHT OF SEATS, TABLES, AND OTHER ARTICLES."
Soaled the 29th September 1877, and dated the 4th April 1877.
PROVISIONAL SPECIFICATION left by the said William Dawes at the Office
of the Commissioners of Patents on the 4th April 1877.
WILLIAM DAWES, of Kingston Grove, Leeds, in the County of York, Engineer.
"IMPROVEMENTS IN THE MECHANICAL MEANS OF VARYING THE HEIGHT OF SEATS,
TABLES, AND OTHER ARTICLES."
In carrying out this Invention I first construct a pair of frames of suitable size,
strength, and proportions for either chair, stool, or table, as required, the lower
frame for receiving or being attached to the supporting legs, and the upper frame
for receiving the stuffing or padding (seat) or the table top, as the case may require.
I then construct four or more upright guides or runners, and fix them by preferenco
to the under side of the upper frame, and in such a manner that they fit either into
the inside corners of or other recesses or holes in the lower frame, and thus con-
stitute perpendicular guides for the up-and-down movement of the upper frame.
I now construct and fit into bearings upon the lower frame a longitudinal
revolving shaft, with milled, notched, or otherwise ornamented band discs or crosses
fixed upon each end outside the before-named frames; and between this shaft and.
the before-described upright guides or runners, and by preference, but not neces-
sarily, in connection therewith I construct the lifting, lowering, and sustaining
mechanism; and I prefer generally that this should consist of a series of toothed
wheels, straight or bevelled, according to size and other circumstances, and racks
upon the before-named upright guides or runners, so arranged and proportioned as
to require from three to four revolutions of the longitudinal shaft to produce the
necessary variation or "travel" of the upper frame and the seat or table top.
In some cases I prefer to substitute chains, guts, cords, or bands as the connecting,
lifting, and supporting means, in lieu of the racks and pinions or wheels, or some of
them.

page_text: To obtain or render practicable greater rapidity of action and adjustment, and at
the same time avoid undue upward friction, I employ as the sustaining medium one
or more special or peculiar friction breaks, so constructed as to possess "grip" or
friction one way only, that is, when turned in one direction, and perfect freedom
when turned in the reverse direction; these I prefer to construct with four or any
convenient number of small rollers, working freely in the same number of pear-
shaped chambers or recesses formed in the body of the break, and with a strong
metal ring encircling these chambers and their rollers, the inner surface of which
ring constitutes one side of each of the before-named recesses, against which the
rollers "grip" or "bite" when the break is turned in one direction, but "lie back"
and give perfect freedom if reversed, as herein-before explained, the actual break or
sustaining friction being round or upon the outside of the before-described loose
metal ring.
As a means of still further increasing the convenience and rapidity of action and
adjustment, in some cases, such, for instance, as music or other stools or seats, I dis-
pense with the before-named hand discs or crosses upon the ends of the longitudinal
shaft (leaving it short within the limits of the outer edges of the frames of the seat),
and I substitute therefor a pair of flat oblong or other conveniently formed "wings"
or projections, which, by a suitable connection with the breaks and the application
of a strong spring action capable of entirely and freely lifting the upper frame,
racks, and seat, enable the occupier or user to alter or adjust the height by the
mere downward or upward pressure of the hands upon or under the before-named
wings or projections; pressing them downwards, releasing or easing one break, and
causing the seat to rise; and pulling them upwards, releasing or casing the other
break, and causing the seat to lower, as the case may require.
By the employment of a second pair of wings or projections the spring action may
be dispensed with.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Dawes in the Great Seal Patent Office on the 3rd October
1877.
WILLIAM DAWES, of Kingston Grove, Leeds, in the County of York, Engineer.
"IMPROVEMENTS IN THE MECILANICAL MEANS OF VARYING THE HEIGHT OF SEATS,
TABLES, AND OTHER ARTICLES."
In carrying out this Invention I first construct a pair of frames of suitable size,
strength, and proportions for either chair, stool, or table, as required, the lower
frame for receiving or being attached to the supporting legs, and the upper frame
for receiving the stuffing or padding (seat) or the table top, as the case may require.
I then construct four or more upright guides or runners, and fix them in most
cases to the under side of the upper frame, and in such a manner that they fit
either into the inside corners of or other recesses or holes in the lower frame, and
thus constitute perpendicular guides for the up-and-down movement of the upper
frame.
tr
I now construct and fit into bearings upon the lower frame (when the guides or
runners are fixed as above to the upper frame) a longitudinal revolving shaft, with
'milled," notched, or otherwise ornamented hand discs or crosses fixed upon each
end outside the before-named frames; and between this shaft and the before-
described upright guides or runners, and by preference, but not necessarily, in
connection with them I construct the lifting, lowering, and sustaining mechanism;
and I prefer generally that this should consist of toothed wheels or "gear," straight
or bevelled, according to size and other circumstances, and "racks and pinions," so
arranged and proportioned as to require froin two to four revolutions of the longi-
tudinal shaft to produce the necessary variation or "travel" of the upper frame and
the seat or table top.

page_text: In some cases I prefer to substitute chains, guts, cords, or bands as the connecting,
lifting, and supporting means, in lieu of the racks and pinions or wheels, or some of
them.
To obtain or render practicable greater rapidity of action and adjustment, and at
the same time stability and safety without undue or undesirable upward friction, I
employ as the sustaining medium one or more special or peculiar friction breaks, so
constructed as to possess "grip" or friction one way only, that is, when turned in
one direction, and perfect freedom when turned in the reverse direction; these I
prefer to construct with four or any convenient number of small rollers, working
freely in the same number of wedge or pear shaped chambers or recesses formed in
the body of the break, and with a strong loose metal ring encircling these chambers
and their rollers, the inner surface of which ring constitutes one side of each of the
before-named chambers or recesses, against which the rollers "bite" or "grip" when
the break is turned in one direction, but from which they "lie back" and allow
of perfect freedom if reversed, as herein-before explained, the actual break or
sustaining friction being round or upon the outside surface of the before-described
loose metal ring.
As a means of still further increasing the convenience and rapidity of action and
adjustment, in some cases, such, for instance, as music or other stools or seats, I dis-
penso with the before-named hand discs or crosses upon the ends of the longitudinal
shaft (leaving it short within the limits of the frames of the seat), and 1 substitute
therefor a pair of flat oblong or other conveniently formed "wings" or projections,
which, by a suitable connection with the breaks and the application of a strong
spring action capable of entirely and freely lifting the upper frame, racks, and seat,
enable the occupier or user to alter or adjust the height by the mere downward or
upward pressure of the hands upon or under the before-named wings or projections;
pressing them downwards, releasing or easing one break, and causing the seat to
rise; and pulling them upwards, releasing or easing the other or reverse break, and
causing the seat to lower, as the case may require.
By the employment of a second pair of wings or projections for lifting, the spring
action may be dispensed with.
In the accompaning Drawings, which are intended to illustrate my Invention,―
Figures 1, 2, and 3 are plan and sectional elevations of a stool, according to what
I have described as the most rapid and convenient arrangement, with the lifting
spring and the wings or projections in connection with the breaks.
Figures 4, 5, and 6 are plan and sectional elevations of a stool with the hand discs
upon the longitudinal shaft, and without the lifting springs.
And Figures 7 and 8 are enlarged part sectional elevations of the breaks.
The same reference letters apply to similar parts in each Figure, a being the upper
frame; b, the lower frame; c, the upright guides or runners; d, the longitudinal
revolving shaft; c, the hand discs upon the same; f, toothed wheels or gear; g, racks
and pinions; h, sustaining breaks; i, rollers in the same; j, pear-shaped chambers
or recesses; k, loose metal ring; l, spring or elastic friction clips; m, flat oblong
wings or projections; n, coiled lifting spring; o, the stuffed or padded part of the
seat; and p, the legs cut short to economize space.
Having now described and particularly ascertained the nature of the said Inven-
tion and the manner in which the same is or may be used or carried into effect, I
wish it to be understood that I do not confine or restrict myself to the precise details
or arrangements which I have described or referred to, as many modifications and
variations may be made therefrom without deviating from the principles or main
features of the said Invention; but what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,-
First. The direct vertical guides, runners, or supports, and racks or pinions, either
conjointly or separately.
Second. The plain longitudinal shaft, not being a screw, and the toothed gear in
connection with the saine

page_text: Third. The special or any similar "one-way" break, or possessing the three-fold
features of freedom one way, "grip" or friction the other way, and release or freedom
from the same when required.
And, Fourth. The oblong or other "side wings" or projections for actuating the
same, and the coiled "lifting spring" for raising the seat, for the purposes and
virtually as or after the manner herein-before explained and set forth.
In witness whereof, I, the said Wiliam Dawes, have hereunto set my hand and
scal, this Twenty-ninth day of September, in the year of our Lord One
thousand eight hundred and seventy-seven.
Witness,
GEORGE EDWIN ILES,
5, Montrose St.,
Leeds.
WILLIAM DAWES. (L.S.)