AN APPLIANCE FOR FACILITATING RAPID AND CORRECT READING OF WEIGHTS ON DIALS OF SPRING BALANCES AND SIMILAR WEIGHING MACHINES
Year: 1885

page_text: I, WILLIAM SIMPSON, of No 14 Elvet Street, Heaton, in the City and County
of Newcastle upon Tyne; Foreman Engineer to Messrs Henry Pooley and Son do
hereby declare the nature of said invention for "AN APPLIANCE FOR FACILITATING
RAPID AND CORRECT READING OF WEIGHTS ON DIALS OF SPRING BALANCES AND
SIMILAR WEIGHING MACHINES to be as follows:-
In all weighing machines, which act by means of springs, an interval of time
must elapse before the weight can be correctly read off, owing to the vibrations, of
the pointer, due to the elasticity of the spring or springs. In some machines this
vibration continues during a considerable part of a minute and thus either time is
wasted or, by reading off before the pointer comes to rest, a wrong weight is
recorded.
The simple appliance which forms the subject of my invention checks the
elastic play of the spring or springs and the pointer is brought to rest almost
instantly recording the correct weight. It consists of attaching to the free end of
the main spring or springs a small controlling metallic or other elastic spring or
springs secured at one end to a fixed point the tension of which constantly acts to
extend the main spring.
Thus when the goods to be weighed are put on the scale, their weight suddenly
extends the main spring or springs, the pointer moving to a point very much in
excess of their weight and would (without the controlling appliance) return, by
the elasticity of the main spring or springs, to a point very much short of such
weight playing backward and forward till it came to rest. The controlling spring
or springs, by their tension on the main springs, act to prevent them contracting,
each time they are extended by the weight of the goods, and thus the pointer is
almost immediately brought to rest at the correct weight to be read off.

page_text: Machines.
I WILLIAM SIMPSON of N° 14 Elvet Street, Heaton in the City and County of
Newcastle upon Tyne, Foreman Engineer to Messrs Henry Pooley and Son 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:
In all weighing machines which act by means of springs, an interval of time
must elapse before the weight can be correctly read off, owing to the vibrations of
the pointer due to the elasticity of the spring or springs. In some machines this
vibration continues during a considerable part of a minute and thus either time is
wasted, or by reading off before the pointer comes to rest, a wrong weight is
recorded.
The simple appliance which forms the subject of my invention checks the
elastic play of the spring or springs and the pointer is brought to rest almost
instantly, recording the correct weight. It consists of attaching to the free end of
the main spring or springs a small controlling metallic or other elastic spring or
springs secured at one end to a fixed point, and the tension of which constantly
acts to extend the main springs.
Thus when the goods to be weighed are put on the scale their weight suddenly
extends the main spring or springs the pointer moving to a point very much in
excess of their weight and would (without the controlling appliance) return by
the elasticity of the main spring or springs, to a point very much short of such
weight playing backward and forward till it comes to rest. The controlling spring
or springs, by their tension on the main springs, act to prevent them contracting,
each time they are extended by the weight of the goods, and thus the pointer is
almost immediately brought to rest at the correct weight to be read off.
DESCRIPTION OF DRAWINGS..
On the accompanying sheet of drawings Figure 1 is a section and Figure 2 a face
view of an ordinary spring balance weighing machine recording the weight on a
dial-S S¹ are the main springs attached at their upper ends to top of case and at
their lower ends to a cross head xx in which is fixed the rod R passing through
bottom of case and fitted with a shackle to which the scale to receive the goods to
be weighed or the goods themselves are attached C C¹are the controlling springs
attached to lower ends of main springs S S and to bottom of case, and constantly
resisting the tendency of the coils of the main springs to close up, after being
extended by the weight applied, beyond their normal length the result being that
the pointer P is quickly brought to rest at the correct weight instead of vibrating
to each side.

page_text: The rack which works the pointer has a small roller behind it which keeps it in
gear with pinion and a small spring K on cross head acts always to keep the teeth
of the rack pressed against those in the pinion.
In experiments with the invention applied to a dial spring balance machine the
pointer was brought to rest in one fourth the time during which it vibrated without
the controlling springs and the effect was still more marked when the goods were
suddenly put into the scale.
Having now fully described and ascertained the nature of my invention and in
what manner the same is to be performed I declare that what I claim is
In weighing machines acting by means of a spring or springs the application or
use of controlling springs for the purpose of preventing reaction of the main spring
or springs and causing the correct weight to be at once indicated substantially as
described and shewn.
Dated the 6th day of February 1886.
Witness:
T. J. DAWSON, F. Inst. P. Agents,
Newcastle upon Tyne.
WILLIAM SIMPSON.