Improved Dynamometer or Weighing Machine.
Year: 1898

page_text: Date of Application, 8th Dec., 1908
Complete Specification Left, 8th Sept., 1899-Accepted, 14th Oct., 1899
Complete Specification Left, 8th Sept., 1899-Accepted, 14th Oct.,
1899
[Communicated from abroad by HERBERT SAMUEL ELWORTHY, of Hotel d'Angle-
terre, St. Petersburg, Russia, and 2, Peel Terrace, St. Heliers, Jersey,
Chemist.]
Improved Dynamometer or Weighing Machine.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 322, High Holborn, in the County of Middlesex, 6, Lord Street,
Liverpool, and 6, Bank Street, Manchester, both in the County of Lancaster, and
Lower Temple Street, Birmingham, in the County of Warwick, Civil Engineer,
do hereby declare the nature of this invention to be as follows:-
The invention consists in an improvement in dynamometers or weight or
strain indicating apparatus, which invention is also applicable for use as a weigh-
ing machine, especially to replace the ordinary spring balance. Its advantages
consist principally in the simplicity of the construction, and the avoidance of
the use of springs of any kind whereby the apparatus is made more certain
uniform and lasting in its operation.
A
The improved apparatus consists of an outer case and a cover to which is
attached a lifting hook or ring, and which has a small air hole or holes.
metallic piston which fits closely in the outer case, and is attached to a piston
rod which passes through an aperture in the lower part of the outer case, is
prolonged to form a hook or ring for attaching the load. A small screw prevents
the rod from being drawn out too far. Between the piston and the bottom of
the outer case a rubber bag is placed, having a hole or passage through the
centre, through which the piston rod passes, fitting tightly. This bag is filled
with water, glycerine, or other suitable liquid, which forms the medium through
which the pressure is communicated to a gauge or other registering instrument.
The rubber bag has a hole or outlet which corresponds to a hole in the lower
part of the outer case, and a thimble and nut make a tight joint with the case.
Through this outlet the liquid communicates by means of a suitable channel with
the gauge or indicator which is preferably attached by means of a taper screw
and nut. There is also a screw cap which may be used for filling the apparatus
with the liquid. The apparatus is primarily devised as a dynamometer, as for
instrance for measuring and recording the tractive force of a locomotive, or the
lifting power of a balloon, by being interposed in the line of force between the
source of energy and the resistance.
Instead of the gauge being attached direct to the apparatus, one or more gauges
may be attached to it by means of .connecting pipes, and these gauges or indi-
cators may be placed at any reasonable distance from the apparatus itself, and
thus simultaneously record the pressure in different places. One or all of the
indicators may be made self registering if desired.
When used as a weighing machine, the device may be attached directly to
the hook of the crane or other lifting device, and in this way a simple and inex-

page_text: pensive form of weighing machine capable of indicating great weights is obtained.
By means of properly arranged flexible tubes, the weight can be indicated in
the engine house or other place as desired,
a8
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, of 322, High Holborn, in the County of Middlesex, 6, Lord Street,
Liverpool, and 6, Bank Street, Manchester, both in the County of Lancaster, and
Lower Temple Street, Birmingham, in the County of Warwick, Civil 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:
The invention consists in an improvement in dynamometers or weight indi-
cating apparatus, which invention is also applicable for use as a weighing
machine especially for replacing the ordinary spring balance. The advantages
consist in the simplicity of the construction and the avoidance of the use of
metal springs whereby the apparatus is made more certain, uniform and lasting
in its operation.
The invention will be best understood by aid of the accompanying drawings
in which:
Figure 1 is a front elevation and
Figure 2 is a side elevation partly sectional of an apparatus constructed accord-
ing to this invention.
A is an upper case provided with a cover B to which is attached a lifting
hook or ring C and which is provided with a small hole D. A piston E fits
closely in the case A and is secured to a piston rod F which passes through an
aperture in the lower part of said case being prolonged to form a hook or ring G
for attaching the load; a small screw H prevents the rod from being drawn out
too far.
Within the case A between the piston E and the lower part thereof is located
a bag I of rubber or other suitable material through which the piston rod F
passes, this bag is filled with water, glycerine, or other suitable liquid through
which the pressure exerted by the piston E is communicated to a gauge or other
registering instrument. The bag is provided with an orifice K corresponding to
a hole in the lower part of the outer case A, a thimble L and nut M being pro-
.vided by means of which the orifice of the bag makes a tight joint with the case.
The outlet K communicates through a suitable channel N with the gauge or
indicator O which may be of any ordinary pattern and is secured by a taper
screw P and nut Q or in any other suitable manner; a screw cap R is provided
through which the apparatus may be filled with liquid.
The operation of the device is very simple.
If the upper part of the case be held fixed by means of the eye-bolt C and
a weight is hung on to the ring G the device will be subjected to tensile stress
and the piston E will be pulled downwards compressing the liquid in the bag I
and this pressure will be registered on the gauge O which may be graduated to
indicate directly the suspended weight.

page_text: Instead of the gauge being attached directly to the apparatus as shewn, one
or more gauges may be connected with it by means of suitable connecting pipes
and these gauges or indicators may be placed at any reasonable distance from
the apparatus, thereby giving a simultaneous indication of the pressure; one or
more of the indicators may be made self-registering or recording, if desired.
The apparatus is primarily devised as a dynamometer, for measuring and
recording the tractive force of a locomotive or the lifting power of a balloon
for example, one end of the apparatus being fixed and the other being attached
to the source of energy.
The apparatus has also been found extremely useful as a weighing machine.
being attached by one end of the hook to a crane or other lifting device, and
the weights to be lifted and weighed being hung on the other end of the
apparatus, in this way a simple and inexpensive form of weighing machine
capable of indicating great weights is obtained.
The indicator or gauge can be located in the engine house or other place if
desired being connected by a suitable tube with the weighing apparatus.
The invention is not confined to the specific form of apparatus illustrated and
described as it is susceptible of considerable variation in detail all of which varia-
tions are included within the scope of the invention.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, as communicated
to me by my foreign correspondent, I declare that what I claim is:-
_
1. A dynamometer or weight indicating apparatus comprising a casing pro-
vided with a piston which is caused to move relatively to the casing when the
apparatus is subjected to tensile stress, the movement of the piston under stress
being opposed by a bag filled with liquid the pressure of which is transmitted
to and measured by a suitable gauge for the purpose of indicating the stress.
2. In a dynamometer or weighing apparatus an annular bag filled with liquid
which is subjected to pressure upon the application of the stress to be measured.
3. The improved dynamometer or weight indicating apparatus constructed
and operating substantially as described with reference to the accompanying
drawings.
Τ
11
011 1
1000
W. P. THOMPSON & Co.,
Of London, Liverpool, Manchester and Birmingham.