IMPROVED MEANS FOR ENABLING PORTABLE SPEED INDICATORS OR COUNTERS TO BE APPLIED TO ROTATING SHAFTS
Year: 1884

page_text: COMPLETE SPECIFICATION,
JOHN YOUNG, of 13 Mowbray Road, Brondesbury, in the County of Middlesex,
Ship and Insurance Broker, and JOHN RICHARDSON, of 64 Torriano Avenue,
Camden Road, in the County of Middlesex, Scientific Instrument Maker, do hereby
declare the nature of our Invention for "IMPROVED MEANS FOR ENABLING
PORTABLE SPEED INDICATORS OR COUNTERS TO BE APPLIED TO ROTATING
SHAFTS" and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
Our Invention relates to an improved carrier, centre or adapter for fitting upon,
or connecting to the spindle, or one of the spindles, of a portable speed indicator or
counter, to enable the same to be applied to a rotating shaft, the speed of which it
is desired to ascertain.
Our improved carrier, centre or adapter is usually made with a pointed or front
portion to fit into the centre hole of a shaft, and with a rear portion to fit the
spindle, or either of the spindles, of the indicator or counter. These two portions
are connected in such a manner that they have freedom of motion relatively to
each other in any direction within certain limits.
If desired, we permanently connect the said front portion to the spindle of the
indicator or counter, instead of to the rear portion of the carrier, centre or adapter,
and, in this case, we dispense with the said rear portion.
It is obvious that the front portion of the said carrier, centre or adapter can,
when required, be made in the form of a socket to fit upon a pointed piece
projecting from the centre of the shaft, the speed of which is to be ascertained.
In carrying our said Invention into practice, we connect the said front portion.
to the rear portion of the carrier, centre or adapter, or to the spindle of the
indicator or counter, either by a spring, or by a suitable universal joint, or by
means of some flexible material.
By constructing the carrier, centre or adapter in this manner, the speed indicator
or counter, to which it is fitted, can be applied to a shaft with its spindle at a
considerable angle to the axis thereof without affecting the indications of speed.
Moreover, if the said shaft vibrates, by reason of its high speed or other cause,
the effect of the vibrations upon the indicator or counter will be considerably
diminished.

page_text: In the accompanying Drawing we have shewn the manner in which we prefer
to construct our improved carrier, centre or adapter.
Figure 1 is a side elevation.
Figure 2 an elevation of one end, and
Figure 3 an elevation of the other end of this device.
The carrier, centre or adapter shewn in these figures is made with a pointed or
front portion A and a rear portion or socket B, which are connected by a spiral
spring C. The socket B is made to fit the spindle, or either of the spindles, of a
speed indicator or counter, and is slotted, as shewn at D, to fit upon each end of
a pin inserted transversely in the said spindle so that the said carrier or centre
will impart rotary motion to the latter. When the pointed portion A is applied
to a rotating shaft, if the spindle of the indicator or counter is not exactly in
line with the said shaft, or if the latter vibrates laterally, by reason of its high
speed or other cause, the spring C will yield or bend and thus allow the said
portion at all times to fit exactly into the centre hole of the shaft, so that the
motion of the said shaft will be accurately transmitted to the spindle of the
indicator or counter and its speed will be correctly indicated thereby. Moreover,
if the shaft has any axial vibration, it will be taken up by the said spring and will
not affect the indicator or counter.
We might employ some flexible or elastic material, or some other means of
obtaining the universal motion, in place of the aforesaid spring, but we prefer the
latter because it combines strength and durability with sufficient flexibility for
the purpose of our Invention.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed, we declare that what
we claim is: The improved carrier, centre or adapter constructed substantially as,
and for the purpose, abqve set forth.