IMPROVEMENTS IN SECURING DOOR KNOBS TO THEIR SPINDLES, AND IN ROSE PLATES USED THEREWITH
Year: 1878

page_text: LETTERS PATENT to Alexander Melville Clark, of Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS
IN SECURING DOOR KNOBS TO THEIR SPINDLES, AND IN ROSE PLATES USED
THEREWITH." A communication from abroad by Job Frances Peacock and John
J.. Zook, both of Reno, in the County of Washoe, State of Nevada, United
States of America
Sealed the 21st February 1879, and dated the 17th September 1878.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 17th September 1878.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN SECURING DOOR KNOBS TO THEIR SPINDLES,
AND IN ROSE PLATES USED THEREWITH." [A communication from abroad by Job
Frances Peacock and John J. Zook, both of Reno, in the County of Washoe, State of
Nevada, United States of America.]
The first part of this Invention relates to a mode of securing the knob to the
spindle, and it consists in the combination of a cam surface on the spindle and a
correspondingly shaped socket in the shank of the knob, whereby the knob is
secured by turning in a direction to bind or lock the two cam surfaces tightly
together, and may be detached by turning it in the opposite direction.
The second part of the Invention relates to a mode of securing the "rose" or
annular escutcheon which surrounds the spindle and forms a bearing for the end of
the knob shank, and it consists in providing said rose with a screw-threaded
extension or hollow shank for engagement with an enlargement in the opening
through which the spindle passes.
The knob may be made entirely of brass or other metal, or either wholly or
partially of porcelain or composition. The spindle has its central portion squared
as usual for engagement with the follower, and the end portions are rounded

page_text: and formed into cam surfaces of the form known as a "snail cam" or "scroll cam,"
said cam having an abrupt shoulder. The socket in the shank of the knob corre-
sponds in form with the cam surface of the spindle, being in fact an internal cam
surface, and is provided with a shoulder corresponding with the shoulder on the
spindle. To secure the parts together the spindle is inserted in the socket of the
knob with the shoulders bearing against each other, and said spindle is pushed in
said socket to the exact required distance. The knob is then turned so as to
separate the two shoulders, which has the same effect as a wedge, and binds or locks
the two cam surfaces tightly together, causing them to adhere so closely as to
prevent them from being separated except by turning the knob forcibly in the
opposite direction. It is not absolutely necessary that the shoulders should be
abrupt, as it is evident that any two cam surfaces of suitable form will operate in a
similar manner, but it is preferable to have the two cam surfaces terminate with
some degree of abruptness, in order to provide for the accurate insertion of the
spindle and also for the disengagement thereof when required. The rose which
surrounds the spindle and forms a bearing surface for the end of the shank of the
knob is provided with a screw-threaded central annular extension or short shank.
When a knob is to be placed in position on a door the opening through which the
spindle passes is enlarged, and the threaded extension of the rose is screwed into
said enlarged portion until the inner surface of the rose lies flat against the surface
of the door. The rose may then be secured by screws passed through it into
the door in the usual way, and will thus be held securely and permanently in
place.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Office on
the 15th March 1879.
,
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Middlesex,
Patent Agent. "IMPROVEMENTS IN SECURING DOOR KNOBS TO THEIR SPINDLES,
AND IN ROSE PLATES USED THEREWITH." A communication from abroad by Job
Frances Peacock and John J. Zook, both of Reno, in the County of Washoe, State of
Nevada, United States of America.
The first part of this Invention relates to a mode of securing the knob to the
spindle, and it consists. in the combination of a cam surface on the spindle and a
correspondingly shaped socket in the shank of the knob, whereby the knob is
secured by turning it in a direction to bind or lock the two cam surfaces tightly
together, and can only be detached by turning it forcibly in the opposite direction.
The second part of the Invention' relates to a mode of securing the "rose or
annular escutcheon which surrounds the spindle and forms a bearing for the end of
the knob shank, and it consists in providing said rose with a screw-threaded
extension or hollow shank for engagement with an enlargement in the opening
through which the spindle passes.
"
In the accompanying Drawing Figure 1 represents a side view, partly in section,
of a knob, spindle, and rose embodying the improvements; Figure 2 is a side view
of the spindle; Figure 3 is a transverse section taken on the line x-x, of Figure 1.
Similar letters of reference indicate corresponding parts in the several Figures.
The knob A may be made entirely of brass or other metal, or either wholly or
partially of porcelain or composition. The spindle B has its central portion squared
as usual for engagement with the latch, and the end portions are rounded and formed
into cam surfaces of the form known as a
"snail cam "
or "scroll cam," said cam
having an abrupt shoulder b shown more clearly in Figure 3. The socket in the
shank of the knob A corresponds in form with the cam surface of the spindle, being
in fact an internal cam surface and is provided with a shoulder a corresponding
with the shoulder b on the spindle. To secure the parts together the spindle B is
inserted in the socket of the knob with the shoulders a and b close together, and
said spindle is pushed in said socket to the exact required distance. The knob is
then turned in the direction indicated by the arrow in Figure 3, which has the same
effect as a wedge, and locks the two cam surfaces tightly together, causing them to
adhere so closely as to prevent them from being separated except by turning the
knob forcibly in the opposite direction. It is not absolutely necessary that the
shoulders a and b should be as abrupt as represented in the Drawing, as it is
evident that any two cam surfaces of suitable form will operate in a similar
manner, but it is preferable to have the two cam surfaces terminate with some
degree of abruptness in order to provide for the accurate insertion of the spindle
and also for the disengagement thereof when required. The rose D which surrounds
the spindle B and forms a bearing surface for the. end of the shank of the knob is
provided with a screw-threaded central annular extension or short shank d. When
a knob is to be placed in position on a door the opening through which the spindle B
passes is enlarged, and the threaded extension d is screwed into said enlarged
portion until the inner surface of the rose lies flat against the surface of the door.
The rose may then be secured by screws passed through it into the door in the usual
way, and will thus be held securely and permanently in place.
I do not confine myself to the precise construction shown herein, but claim the
right to vary the form to any extent which will not materially change the character
of the Invention.
Having described the nature of the Invention, and the manner of performing the

page_text: same, I declare that what I claim as the Invention to be protected by the herein-
before in part recited Letters Patent is,―
1st. As a means for attaching knobs to spindles, the combination of a spindle
provided with an external cam surface, and a knob having its socket provided with
an internal surface of a corresponding form with said cam surface, substantially as
and for the purpose herein described.
2nd. A. rose or annular escutcheon provided with a screw-threaded central annular
'extension or shank in combination with a door knob and spindle, substantially as
and for the purpose herein described.
In witness whereof; I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Fourteenth day of March, in the year of our Lord
One thousand eight hundred and seventy-nine.