Improvements in Clock Pendulums.
Year: 1891

page_text: Date of Application, 30th Jan., 1891
Complete Specification Left, 1st May, 1891-Accepted, 6th June, 1891
PROVISIONAL SPECIFICATION.
Improvements in Clock Pendulums.
I, HENRY SMITH PRENTISS, of 1264 Waverly Place, North Elizabeth, in the
County of Union and State of New Jersey, one of the United States of
America, Mechanical Engineer, do hereby declare the nature of my invention to
be as follows:-
The rod of the pendulum is provided with a main bob as usual and with an
adjusting nut which engages with the screw shank at the lower end of the
pendulum and supports the main bob. Engaging with the same screw shank
below the adjusting nut is a metallic rating bob which is formed of a milled head
or weight proper and a cylindrical portion, or sleeve, split through a major
portion of its length. The upper end of the sleeve is reduced in diameter .and
provided with an internal screw thread constructed to engage with the aforesaid
screw shank of the pendulum, the whole acting in the manner of internally
threaded spring jaws, the upper threaded portions of which engage with..said
screw shank.
The upper end of the rating bob is reduced in diameter sufficiently to fit
snugly about the screw shank, the split sleeve thus exerting sufficient pressure at
all times to prevent the said rating bob from turning with the oscillations of the
pendulum, while at the same time the pressure is not such as to cause the pendulum
to be twisted when the bob is adjusted by hand. Furthermore as the screw threads
wear the elasticity of the sleeve will take up for wear.
Dated this 30th day of January 1891
HENRY S. PRENTISS.
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.
HENRY S. PRENTISS.
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Clock Pendulums.
I, HENRY SMITH PRENTISS of 1264 Waverly Place, North Elizabeth, in the
County of Union and State of New Jersey, 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 :-
My invention has reference to improvements in clock pendulums and especially
to the supplemental or rating bobs usually provided in connection with the main
bob for facilitating the adjustment of the pendulum for time.
Heretofore ordinary nuts in engagement with the screw shank of the pendulum
have been used for this purpose, but such nuts necessarily being fitted loosely to
the screw shank, so as to turn without twisting the pendulum, and not having the
weight of the main bob to support, are influenced by the oscillation of the
pendulum and caused to work downward, thereby throwing the pendulum out of
adjustment.
My invention has therefore for its object to provide a supplementary or rating
bob which can be easily turned for adjustment and will not be influenced by the
motion of the pendulum, even after the thread has become worn.
To this end my invention consists essentially in combining with a pendulum, a
supplementary or rating bob composed of a split sleeve having its upper portion

page_text: reduced and provided with an internal screw thread, all of which is more fully
pointed out in the following Specification and claim and illustrated in the accom
panying drawings in which :-
Figure 1 represents a face view of a pendulum embodying my invention, part
being broken away.
Figure 2. is a sectional side elevation of the same.
Figure 3. is a sectional elevation of the supplementary or rating bob, detached.
Similar letters indicate corresponding parts.
In these drawings the letter A designates the rod of the pendulum, B is the
main bob and C the adjusting nut supporting the former and engaging with the
screw shank D secured to the lower end of the rod A, all as usual.
The supplementary or rating bob E is made of metal and formed with the milled
head or weight proper a, and a cylindrical portion or sleeve b, split through a
major portion of its length. The upper end of the sleeve is reduced in diameter
and provided with an internal screw thread c constructed to engage with the screw
shank D of the pendulum, the whole acting in the manner of internally threaded
spring jaws, the upper threaded portions of which engage with said screw shank.
The upper end of the rating bob is reduced sufficiently in diameter to fit snugly
about the screw shank D, the split sleeve then exerting sufficient pressure at all
times to prevent the bob from turning with the oscillations of the pendulum, while
at the same time the pressure is not such as to cause the pendulum to be twisted
when the bob is adjusted by hand. Furthermore as the screw threads wear the
elasticity of the sleeve will take up for wear.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In combination with a pendulum, a supplemental or rating bob provided
with a split sleeve and internal screw threads, substantially as described.
2. A pendulum bob having a split sleeve reduced in diameter at its upper end
and provided with an internal screw thread, substantially as described.
DaleⱭ UHIS 1st QRY 01 May IONI.
DateⱭ tHIS ISU QRULY O1 May 1831.
H. S. PRENTISS.
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.