Recording Temperatures.
Year: 1885

page_text: Recording Temperatures.
I JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this invention for "IMPROVEMENTS IN
"
INSTRUMENTS OR APPARATUS FOR REGISTERING OR RECORDING TEMPERATURES
which Invention has been communicated to me from abroad by Mess Richard
Brors of Paris in the Republic of France Mathematical Instrument Makers, and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:—
This Invention relates to instruments or apparatus for registering or recording
the temperature at any place during a certain period of time. The instrument or
apparatus constructed according to this Invention consists of a metallic thermo-
meter working with a Bourdon tube and may be employed with advantage in the
arts generally being however especially useful in brewing and similar operations.
I will describe with reference to the accompanying Drawings the manner in which
the Invention may be carried out in practice.
Figure 1 is an elevation of the mechanism with the case in section and Figure 2
is a corresponding partial plan.
In the generality of instruments of the description employed in the arts all the
parts of the mechanism and especially the part directly affected by the variations
of temperature are enclosed in a case provided with apertures to enable this part
to be brought to the same temperature as that of the surrounding atmosphere.
This arrangement is attended with obvious disadvantages; if the apertures be
made too large the case becomes filled with dust which sticks to the wheels and
obstructs the working of the apparatus; if on the contrary they be too small the
external variations of temperature are not properly. transmitted to the interior of
the case and the instrument is not sufficiently sensitive to changes of temperature
and does not register accurately. In order to remedy this disadvantage the
sensitive part proper namely a thermometer Bourdon tube t is arranged according
to this Invention externally to a case B containing the registering or recording
mechanism consisting of a cylinder A actuated by clock work a style or tracing
point s and the connecting links and levers hereinafter described. The case B can
thus be entirely closed with the sole exception of a small aperture for the passage
and slight movement of the connecting rod f which transmits motion to the tracer

page_text: The
in accordance with the variations in the curve of the Bourdon tube.
cylinder A has a slow rotary motion imparted to it by a suitable motor such
as clock work. A sheet is wrapped round this cylinder and is divided to indicate
periods of time and degrees of temperature.
A tracer 8 pressing against this cylinder is provided with a marking point
or instrument such as a pencil or a pen charged with ink and is capable of
oscillating on a fixed point o so that the marking point describes an arc of a circle
upon the sheet on the periphery of the cylinder as indicated in the drawing
supposing the cylinder to be stationary. At a constant temperature the marking
point is stationary but a change of temperature produces an alteration in the curve
of the Bourdon tube t whereby the arm fand link d are moved and the spring arm
or lever carrying the marking point is deflected or caused to oscillate on the
centre o to an extent corresponding -to the change of temperature. The cylinder
being caused to continuously rotate upon its axis with a regular motion it will be
readily understood that the marking point will trace upon the sheet on the
cylinder a curve which records all variations in the temperature of the surrounding
atmosphere so long as the apparatus is in action.
The marking point can be moved out of contact with the cylinder by turning a
rod q on a stud c by means of a knob or button b so as to press the said rod against
the spring arm r and move it away from the cylinder.
An arm rigidly connected to the extremity of the Bourdon tube is held up by a
counterspring coiled round a screw v. It is simply necessary to turn a nut e on
the said screw in order to adjust the instrument by setting the Bourdon tube and
consequently the marking points in the proper position corresponding to a given
temperature ascertained by means of an ordinary thermometer. The adjusting.
apparatus and the Bourdon tube arranged externally to the case may be protected
from injury by an open work covering as indicated at g in figure 1.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is
First. The general construction and arrangement of parts constituting an
improved instrument or apparatus for registering or recording temperature and
consisting essentially in the employment of a metal theremometric Bourdon tube
in combination with a marking instrument and a registering cylinder substantially
as hereiubefore described.
Second. In an instrument or apparatus for registering or recording temperature
dividing the registering or recording mechanism proper from the sensitive part
acted on directly by the variations in the temperature the said sensitive part being
arranged externally to the case containing the said mechanisin substantially as
hereinbefore described and illustrated in the accompanying drawings.
Third In an instrument or apparatus for registering and recording temperature
the employment of the adjusting mechanism composed of an arm 7, spring r screw v
and nut e arranged and operating in the manner and for the purpose substantially
as hereinbefore described with reference to the accompanying drawings.
Fourth. The arrangement and combination of parts constituting the temperature
registering or recording instrument hereinbefore described and illustrated by the
accompanying Drawings.