Improvements in Fastenings for Door Knobs and the like.
Year: 1894

page_text: Date of Application, 11th Dec., 1894-Accepted, 13th Apr., 1895
COMPLETE SPECIFICATION.
Improvements in Fastenings for Door Knobs and the like.
1, FRANCIS HENRY RICHARDS of 112 Edwards Street in the City of Hartford,
County of Hartford, and State of Connecticut, one of the United States of
America, Mechanical Engineer, do hereby declare the nature of this invention,
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :—
This invention relates to that class of attachments or clamping-couplings adapted
for removably fixing hubs, knobs and like parts to spindles or like rods by means
of clamping-devices; the object being to provide a simple and powerful two-part
fastening-device in which the hub or stem constitutes the spindle-clamp, and in
which the clamp-sleeve has no longitudinal movement relative to the other parts
during the operation of securing the hub or stem in its proper position upon the
spindle. When my improvement is applied to the stem of a door-knob, this may
be placed with the end of its clamp-sleeve or stem closely against the escutcheon
or bearing-plate upon the door, and then rigidly fixed in place without any longi-
tudinal movement of any part thereof relatively to the spindle; at the same time
the separate spindle-clamp heretofore generally used in this class of knob-attachments
is dispensed with, and a knob-fastening is produced which is simple and durable in
construction, effective in its operation and of low cost to manufacture.
The invention consists in an improved fastening-device for knobs, and the like
consisting of a compressible tubular stem, bored or recessed to receive a spindle and
having on the compressible portion thereof inclined wedge-bearings and having a
fixed clamp-sleeve abutment, combined with a clamp-sleeve having internal inclined
bearings adapted for engaging with the bearings of the stem, and having its inner
end in engagement with said abutment, and adapted to be turned for compressing
the stem, substantially as hereinafter described.
It also consists in the special construction and organization of the several parts,
of the knob attachment, substantially as hereinafter described.
In the drawings accompanying and forming a part of this Specification,
Fig. 1 is a vertical longitudinal section of a door-knob furnished with my
improvements, the view being taken on line 1-1 of Fig. 2, and the usual squared
spindle being shown in side elevation.
Fig. 2 is an end view of the knob-attachment looking from the right-hand in
Fig. 1.
Fig. 3 is a side elevation of the knob-stem. Fig. 4 is an end view of the same
looking from the right-hand in Fig. 3, a portion of the knob being broken away.
Fig. 5 is a side elevation of the clamp-sleeve. Fig. 6 is an end view of the
same.
Fig. 7 is a longitudinal section of said sleeve, and
•
Fig. 8 an enlarged sectional detail of the spindle, knob-stem and clamp-sleeve
taken on line 8-8, Fig. 1.
Similar characters designate like parts in all of the figures.
The spindle S is, or may be, as shown in the drawing, of the usual squared
cross-sectional form and of uniform diameter throughout the length thereof. The
hub or stem of the knob K is shown having a suitable central opening and should be
itted to slide freely and closely upon the spindle S. Said stem should also be slitted
ongitudinally through one or both sides as shown at 5, to make the walls yielding ;
D

page_text: these walls, in the form of knob-stem herein shown, are preferably two in number,
being designated by 6¹, and 6". See Fig. 4.
The yielding walls of the knob-stem each have formed thereon, as herein shown,
peripherally thereof, a suitable number of inclined or wedge-like bearing-faces or
steps, 9, the planes of the bearing-faces of one wall spirally coinciding with those
of the other wall, and forming together a continuous inclined spiral path or wedge,
which preferably occupies a considerable portion of the length of the hub or stem.
Said bearing-faces of the hub or stem are adapted to be engaged by correspondingly
arranged bearing-faces, 10, formed upon the interior of the thimble or clamp-
sleeve 8. For assembling the fastening-device, said clamp-sleeve is turned upon
the knob-stem, after the manner of putting a nut on a bolt, until the sleeve rests
against the stop-shoulder, 12, this operation being performed prior to the placing
of the knob on the spindle. The bearing-faces 9 upon the stem and the bearing-
faces 10 within the sleeve are relatively so formed as to closely intermesh, and
so that the sleeve may still be readily turned for assembling and disassembling the
parts.
In assembling the parts and securing the knob-stein on the spindle, the clamp-
sleeve is first placed upon the stem in loose engagement with the abutment or
shoulder 12, the outer end of said clamp-sleeve being, when in this position,
preferably flush with the outer end of the stem as clearly shown in Fig. 1. At
this time the walls of the stem are not compressed; and said stem is in a condition
to be freely slid lengthwise of the spindle. The knob-stem being now placed upon
the spindle in the required position, the clamp-sleeve will be forcibly turned
forward (usually by means of a wrench engaging a hexagonal or squared portion, 13,
thereof,) in the proper direction, as indicated, for instance, by the arrow shown in
Fig. 2; this will force the abutting end 11 against the abutment 12 of the stem,
(said abutment preventing any forward longitudinal movement of the sleeve withi
relation to the stem,) and, by the reaction of said force, cause the wedge-like
bearing-faces 10 of said sleeve to ride upward upon the inclined bearing-faces 9 as
shown by the dotted line 21 in Fig. 3, thereby compressing or closing together the
yielding walls 61, 6" of the stem. This lateral or closing movement of the said
walls is, of course, proportionate to the rotary movement of the sleeve, having
regard to the inclination of the bearing-faces.
The hub or stem being rigidly closed upon the spindle, by so powerful a wedge-
device as described, is securely held against either lateral or longitudinal movement
on the spindle, and with the clamp-sleeve forms a simple and effective knob-
attachment, in which there is no longitudinal movement whatever of any part upon
or relatively to the spindle during the operation of fastening and unfastening the
hub or stem to and from the rod or spindle. This is an important desideratum,
since it permits the hub or stem to be first accurately adjusted to its exact position,
and then to be firmly secured in place, without any allowance being made for the
longitudinal movement of any of the parts: heretofore such an allowance has
generally been necessary for properly placing door-knobs upon their spindles when
these are in the door ready for use. This feature obviates the necessity for using
any rose, or tongue-and-groove devices, to cover the joints of the structure.
The described construction of the fastening-device results in a very rigid,
compact and powerful knob-stem and attachment, with no parts to become loose
and rattle and having all the requirements of a first-class article; at the same time,
the construction is such that the fastening-device may be easily manufactured by
simple, well-known and inexpensive means and methods, thereby producing a device
of superior character at a low cost.
When the spindle is of an angular cross-sectional form as shown in the drawings,
and is smaller than the bore of the stem, this in closing is forced into a slightly
irregular external shape, so that its peripheral lines are not truly circular. For
accommodating this deviation and to preserve a relatively perfect operation of the
parts, the sleeve is made of small thickness relatively to the diameter thereof, so
that it will, when forcibly tightened, readily conform in cross-sectional shape to

page_text: the irregularities of the closed stem, and thereby maintain the perfect co-action of
the several parts of the fastening. In practice, also, the sleeve, by reason of its
relatively small thickness, and being of elastic metal (preferably bronze), expands
somewhat, and thus overcomes the effect of any slight differences in the shape and
size of the spindle at different points in the length thereof.
The diametrical inclination, indicated by the dotted line 20, Fig. 1, of the
wedge-faces relatively to the spindle, should correspond substantially with the
normal angle of repose, or come within about the minimum and maximum limits of
five and twenty-five degrees, respectively, from said spindle, or from the axis of the
stem; in practice, I prefer said angle should be about ten degrees, substantially as
shown in the drawing, and that the wedge-faces should be one-eighth to one-sixth of
an inch wide, for use in knob-fastenings of ordinary sizes.
I do not limit myself to the use of a hub or stem having two yielding walls 61, 6",
since it is obvious that said stem may be slitted to form three or more yielding
walls, or may have only one slit, and consequently only one such wall. The
construction shown, however, is deemed preferable, the slits 5 being, preferably,
where an angular spindle is used, in alignment with the plane of the opposite angles
or corners of said spindle. Neither is my invention limited to the use of a spindle
that is square, or of any particular angular cross-section, for a round spindle may
be used if desired.
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:
1. As a fastening-device for knobs, the hereindescribed combination with a
compressible tubular-stem adapted to receive a spindle, and having on the com-
pressible portion thereof inclined wedge-bearings and having a fixed clamp-sleeve
abutment, of the clamp-sleeve having internal inclined wedge-bearings adapted
for engaging with the bearings of the stem and having its inner end in engagement
with said abutment and adapted to be turned for compressing the stem, substantially
as described.
2. The herein-described two-part fastening device, consisting of a compressible
tubular stem having a fixed clamp-sleeve abutment and having upon the com-
pressible portion thereof an external spiral wedge-bearing in the form of a screw-
thread and inclined toward the axis of the stem and toward said abutment,
combined with a clamp-sleeve having its inner end adapted to bear against said
abutment and having an internal spiral-wedge-bearing in the form of a nut-thread
and corresponding to and coacting with the screw-thread wedge-bearing of the
stem, whereby said sleeve, being in the nature of a nut, is adapted to be turned
for compressing the stem without longitudinal movement relatively to said stem,
and whereby the stem and sleeve may be assembled and disassembled by screwing
on and screwing off the sleeve, substantially as described.
Dated this 26th day of November A.D. 1894.
FRANCIS HENRY RICHARDS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.