Improvements in the Construction of Base Castings and Seat Supports of Revoluble Chairs.
Year: 1898

page_text: Date of Application,
Mar., 1908
Complete Specification Left, 28th Nov., 1898-Accepted, 22nd Mar., 1899
Complete Specification Left, 28th Nov., 1898-Accepted, 22nd Mar., 1899
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Base Castings and Seat Supports
of Revoluble Chairs.
I, PETER JENSEN, of 77, Chancery Lane, in the County of Middlesex, Chartered
Patent Agent, do hereby declare the nature of this invention, which has been
communicated to me from abroad by the Gilson Manufacturing Company, located
in the City of Port Washington, in the County of Ozaukee, and State of Wisconsin,
United States of America, to be as follows:-
:―
This invention consists in forming the chair-base casting which receives the legs
of the chair with a vertical longitudinal smooth circular-bore, and with a nut
in bearing contact with the casting, a longitudinally grooved screw-spindle engag-
ing the nut and a slip-collar above the nut-thread having a spline engaging the
spindle-groove, together with suitable means whereby the slip-collar is normally
held to rotate with said nut, whereby, when the slip-collar is in spline-engage-
ment with the spindle and held to rotate with the nut in bearing contact with
the stationary base-casting, all three of the former parts may turn together without
disturbing vertical adjustment of said spindle to which the seat-frame spider of a
chair is rigidly connected, but if said collar be adjusted so as to bring its spline out
of the spindle-groove or to prevent its rotation with said nut, the latter may be
operated to serve its function as a means for raising or lowering the aforesaid
spindle, while to prevent the nut from being lifted away from the base-casting,
any suitable or desirable retaining means may be employed.
Dated this 22nd day of March 1898.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.
Improvements in the Construction of Base Castings and Seat Supports
of Revoluble Chairs.
I, PETER JENSEN, of 77, Chancery Lane, in the County of Middlesex, Chartered
Patent Agent, do hereby declare the nature of this invention, which has been
communicated to me from abroad by the Gilson Manufacturing Company, located
in the City of Port Washington, in the County of Ozaukee, and State of Wisconsin,
United States of America, and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement: --
This invention has for its object to simplify and cheapen the manufacture of
that class of chairs in which vertically-adjustable revoluble seat-supports are
embodied and to that end the said invention consists essentially in forming the
chair-base casting which receives the legs of the chair with a vertical longitudinal

page_text: smooth circular bore, and with a nut in bearing contact with the casting, a longi-
tudinally grooved screw-spindle engaging the nut and a slip-collar above the nut-
thread having a spline engaging the spindle-groove together with suitable
means whereby the slip-collar is normally held to rotate with said nut, whereby,
when the slip collar is in spline-engagement with the spindle and held to rotate
with the nut in bearing contact with the stationary base-casting, all three of
the former parts may turn together without disturbing vertical adjustment of said
spindle to which the seat-frame spider of a chair is rigidly connected, but if said
collar be adjusted so as to bring its spline out of the spindle-groove or to prevent
its rotation with said nut, the latter may be operated to serve its function as a
means for raising or lowering the aforesaid spindle, while to prevent the nut from
being lifted away from the base-casting, any suitable or desirable retaining means
may be employed, all as hereinafter more particularly set forth with reference to
the accompanying drawings, and subsequently claimed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 of the drawings represents a view of an improved construction and
arrangement of parts according to one form of the invention, certain of these parts
being in vertical transverse section, as indicated by line 1-1 in the succeeding
figure; Figure 2, a plan view, partly in horizontal section, on the plane indicated
by line 22 in the preceding figure; Figure 33, a partly vertical transverse
sectional view of a construction and arrangement of arts constituting another
form of this invention, and Figure 4, a similar view of still another form of said
invention.
Referring by letter to the drawings, A represents a smooth-bore chair-base
casting, and B a nut, that has bearing contact with the casting, preferably within
the same, so as to economize space. Engaging the nut is a screw-spindle C,
having a longitudinal groove b, engaged by a spline e, extending inward from a
slip-collar D, that surrounds the spindle above the nut-thread. The slip-collar
is normally held to rotate with the nut, and various means for accomplishing
this result may be utilized.
The slip-collar being in spline-engagement with the spindle and held to rotate
with the nut in bearing contact with a stationary base-casting, all three of the
former parts may turn together without disturbing vertical adjustment of said spindle
to which the seat-frame spider of a chair is rigidly connected; but if said
collar be adjusted so as to bring its spline out of the spindle-groove or to prevent
its rotation with said nut the latter may be operated to serve its function as a means
for raising or lowering the aforesaid spindle.
To prevent the nut from being litted away from the base-casting, any suitable
retaining means may be employed, and this feature of the construction and
arrangement of parts is hereinter mode particularly set forth.
The
is shown a having on upper annular flange d, from which the
Stoke
of a hand-whed Erodiste, and a. Shown in Figure 1 the flange may be
the only port of said nut in hearing contact with the base-casting. In Figure 4
the lower end on the ant is shown brating contact with the base-casting, and the
latter figure also shows the nut-flange in like contact with said base-casting.
Hence it is to he understood that it is practical to have either or both of these
nut-surfaces bar upon the aforesaid base-casting. In Figures 1 and 4 the vertical
portion of the nut is shown out of fictional contact with the chair-base casting.
The slip-collar shown in Figures 1, 2 and 3 is of elliptical shape and has such
area of aperture as will permit its longitudinal adjustment to bring the spline c
out of engagement with the spindle-groove and back of the vertical face of a bevel-
top lug f, extended upward from the nut, the latter and the lug being preferably
cast in one piece. The elliptical slip-collar is provided with a beveled notch
for the engagement of the nut-lug f, and said collar is also shown as having a
handle 9, by which it may be conveniently adjusted. A sliding movement of the
elliptical slip-collar from the position shown in full lines, Figures 1 and 2, will

page_text: cause its notched portion to ride upon the nut-lug f until the spline c, thus dis-
engaged from the spindle-groove, drops back of said lug, as shown by dotted lines
in said Figure 2. The slip-collar being in the position last described, it may
rotate with the nut when the latter operated to vertically adjust the spindle,
it only requiring one hand of the operator to effect this adjustment after said collar
has been positioned so as to lock its spline out of engagement with the spindle-
groove. However, one hand may be employed to lift and hold the slip-collar
clear of the lug on the nut while the latter is being operated by the other hand
to vary vertical adjustment of the spindle, and in this case it is not necessary to
disengage the collar-spline from the spindle-groove.
In Figure 4, the slip-collar 1) is shown as having the form of a washer provided
with a depending lug h, that normally comes between spokes of the hand wheel
portion E of nut B, whereby said collar, having its spline engaged with the longi-
tudinal groove of the spindle, is held to rotate with the latter and said nut. By
lifting and holding the latter form of slip-collar so as to have its lug free of the
nut, rotation of the latter will effect vertical adjustment of the spindle.
In Figures 1 and 4 a short nut B is shown engaging a counterbore at the
upper end of the chair-base casting and this form of nut is also shown as being
provided with an exterior annular groove engaged by a screw G. adjustable in
said chair-base casting. By having the screw engaged with the groove of the
nut the latter cannot be lifted away from the chair-base casting.
In Figure 3 the nut is shown long enough to extend down through the bore
of the chair-base casting, and a screw G¹ run into the lower projecting portion of
this latter form of nut serves to prevent lift of the same from said casting.
In any form of this invention the construction and arrangement of parts are
very economical owing to the simplicity of the structure.
It is also to be observed that the seat and base portions of a chair embodying
this invention may be readily separated for a knockdown shipment, and there are
no parts liable to be lost at any time from said chair.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. A chair-base casting, a nut in bearing contact with the casting, a longitu-
dinally-grooved screw-spindle engaging the nut, a slip-collar above the nut-thread
having a spline engaging the spindle-groove, and suitable means whereby the
slip-collar is normally held to rotate with said nut.
2. A chair-base casting, a rotative nut having bearing contact with the casting
inside the same, a longitudinally-grooved screw-spindle engaging the nut, a slip-
collar above the nut-thread having a spline engaging the spindle-groove, and
suitable means whereby the slip-collar is normally held to rotate with said nut.
3. A chair-base casting, a nut in bearing contact with the casting, suitable
means for preventing lift of the nut from said casting, a longitudinally-grooved
screw-spindle engaging said nut, a slip-collar above the nut-thread having a
spline engaging the spindle-groove, and suitable means whereby the slip-collar
is normally held to rotate with the aforesaid nut.
Dated this 28th day of Vavomber 1808
JENSEN & SON,
77. Chancery Lane, London, W.C., Patent Agents.