Improvements in Apparatus for Measuring Temperatures and Pressures.
Year: 1891

page_text: Date of Application, 15th July, 1891
Complete Specification Left, 19th Apr., 1892-Accepted, 2nd July, 1892
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Measuring Temperatures and
Pressures.
I LOUIS DAMAZE of Rue de la Tour d'Auvergne, Paris, in the Republic of
France, Engineer, do hereby declare the nature of this invention to be as follows:-
This invention for improvements in apparatus for measuring temperatures and
pressures has for its object to construct an apparatus which shall indicate both high
and low temperatures and which can be adjusted without taking to pieces, and as
the relation between the pressures of vapours in contact with their generating
liquids and their temperatures is known, which shall also indicate pressures.
For certain dimensions the expansion of mica by heat is equal to the contraction
of earthenware up to a certain temperature, and for other dimensions the expansion
of mica is equal to the contraction of slate. Also mica is a dielectric.
One form of apparatus for measuring temperatures constructed according to this
invention consists essentially of a base column formed of superposed or aligned
cylinders of mica and earthenware, or of mica and slate, so proportioned that its
total length is constant for all temporatures. One end of this base column bears
against an adjustable stop on or is adjustably attached to the outer or free end of a
surrounding copper or other tube attached at its inner end to the framework
carrying the indicating mechanism. A rod is pressed upon the other end of the
base column, which moves away from the framework as the copper tube expands,
by means of a lever acted on by a spring; and an adjustable arm on this lever is
connected to an adjustable arm fixed on the axis of a sector gearing with a pinion
on the axis of the indicating pointer so that as the copper tube expands or contracts
it operates the pointer to indicate the temperature. There are thus three means
for adjusting the apparatus. In a modified construction of indicating mechanism
the rod bearing on the base column acts directly on an adjustable arm forced
against it by a spring and attached to the toothed sector.
In another arrangement, the base consists of a compound strip of steel and brass
joined together, with an intermediate strip of mica, by rivets or other suitable
means and formed into a helix. The coiling and uncoiling of the compound helical
strip the extension of which is prevented-is communicated by a crank pin
attached to the end of the helix to an adjustable arm of a sector gearing with
a pinion on an indicating axis; or by a helical cam to the rod mentioned in the first
described arrangement.
The apparatus may be provided with electric signals indicating when a certain
temperature is attained.
Dated this 15th day of July 1891
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, Agents.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Measuring Temperatures and
Pressures.
I, LOUIS DAMAZE of Rue de la Tour d'Auvergne Paris, in the Republic
of France, Engineer, do hereby declare the nature of this invention and in wha'.
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
This invention for improvements in apparatus for measuring temperatures and
pressures has for its object, to construct an apparatus which shall indicate both high

page_text: and low temperatures and which can be adjusted without taking to pieces, and as
the relation between the pressures of vapours in contact with their generating
liquids and their temperatures is known, which shall also indicate pressures.
For certain dimensions tlie expansion of mica by heat is equal to the contraction
of earthenware up to a certain temperature and for other dimensions the expan-
sion of mica is equal to the contraction of slate. Also mica is a dielectric. An
apparatus for measuring temperatures constructed according to this invention is
based on the above physical facts.
One form of apparatus consists essentially of a base columnformed of superposed
or aligned cylinders of mica and earthenware, or of mica and slate, so proportioned
that its total length is constant for all temperatures. One end of this base column
bears against an adjustable stop on or is adjustably attached to the outer or free
end of a surrounding copper or other tube attached at its inner end to the framework:
carrying the indicating mechanism. A rod is pressed upon the other end of the
base column, which moves away from the framework as the copper tube expands,
by means of a lever acted on by a spring; and an adjustable arm on this lever is
connected to an adjustable arm fixed on the axis of a sector gearing with a piniou
on the axis of the indicating pointer so that as the coppere are thus three means for
tube expands or contracts
it operates the pointer to indicate the temperature.
adjusting the apparatus. In a modified construction of indicating mechanism the
rod bearing on the base column acts directly on an adjustable arm forced against it
by a spring and attached to the toothed sector.
In another arrangement, the base consists of a compound strip of steel and brass
joined together, with an intermediate strip of mica, by rivets or other suitable
means and formed into a helix. The coiling and uncoiling of the compound helical
strip is communicated by a crank pin attached to the end of the helix to an
adjustable arm of a sector gearing with a pinion on an indicating axis; or by
a helical cam to the rod mentioned in the first described arrangement.
The apparatus may be provided with electric signals indicating when a certain
temperature is attained.
i
In order to more clearly explain my invention I attach hereto the following
explanatory drawings
Fig. 1. shows elevation and section of the column.
Fig. 2 shows the tubes in which the rod is placed.
Figs. 3 and 4 represent plan and side view of the mechanism for a horizontal dial.
Fig. 5 shows the helix.
Figs. 6 and 7 show the front and side views of the mechanism for a vertical dial.
Fige. 8 and 9 show two general views of a horizontal and a vertical dial.
Fig. 10 shows the arrangement of the apparatus for measuring high temperatures.
Fig. 11 shows the arrangement of the apparatus for blast furnaces.
In Fig. 1 is shown the column, which is composed of the necessary number
of cylinders in earthenware and mica 2. This column rests freely on the small
cap 3 bearing on the regulating screw 4 which fits into the nut 5 closing the tube 7
made of copper steel platinum or other material and is secured by the lock nut 6.
On the column formed of the cylinders 1 and 2 (Fig. 2) the rod 8 freely rests,
round the upper part of which, with the rounded top, 9 is twisted a helical spring 10
between two small caps 11 and 12. This rod works in an iron tube 13 at the lower
end of which is fixed the tube 7 and the whole is enclosed in a protective tube 14
which may be partly within the masonry.
Figs. 3 and 4 represent the mechanisin for a horizontal dial.
On the plate 15 is the spindle 16 hung between the points 17 and 18 and which
carries the Z lever 19 the lower part of which dips into the socket 20, through a
part cut away in the plate 15, in order to be in contact with the rod 9. On the
sockot 20 is screwed the tube 13. The spindle 16 also carries the screw 21, which
holds the pivot of the needle 22. This needle bears with its point in the conical
cup 23 which can be adjusted on the arm 24 fixed solidly to the spindle: 25 of the
seotor 26.

page_text: To the screw 21. are attached two helical springs one, 27, is fixed to the plate 15
and the other 28 to the conical cup 23. The toothed sector 26 engages in the
pinion 29 the spindle 30 of which carries the indicating needle 31. The movement
of the sector 26 is limited by the stop-sorews 32 and 33, and sudden jerky
movements are avoided by the spring 34 fixed on the plate 15 at 35 and which
bears on the small pin 36 fixed on the sector 26.
Fig. 5. The helical arrangement shown in this figure is made as follows:-A hollow
brass cylinder 37 of suitable dimensions -is enclosed in a cylinder formed of sheets
of mica 38 and finally in one of steel 39, the three cylinders being cut in one
operation into a helix. They are then rivetted together and the helix 40 is in this
way constructed. Mica being a dielectrio prevents any electrical action between
the brass and steel.
Figs. 6 & 7. The helix 40 is enclosed by the tube 7 (Fig. 2) and is fixed at its
lower end, the upper part of the helix is fixed to the rotating rod 41 which passes
freely through the nut 42 and is fitted into and fixed to the tube-43 inside the
support 44 of the mechanism. On the tube 43 is fixed by any suitable means the
small plato 45 carrying the pin 46. On the standard 44 is fixed the plate 15, on
which is the spindle 25 of the sector 26 carrying another tooth 47. A spring 27 is
fixed at one end to the sector at 48 andat the other end to the plate at 49. The
sector engages with the small pinion wheel 29, the spindle 30 of which carries the
indicating needle 31.
Should it be desired to use the columu 1-2 (Fig. 1) in connection with mechanism
for a vertical dial (Figs. 6 & 7) an arm 50 is added to the rod 9 which acts then on
a little friction wheel 51 (Fige. 6 & 7) which can be adjusted in the slot 52 of the
sector 26.
If it is desired to.make use of the helix 40 in connection with mechanism for a
horizontal dial (Figs. 3 & 4) the small plate 45 (Figs. 6 & 7) is replaced by the
helical cam 53 (Fig. 5) which then acts on a small friction wheel 54 (Fig. 4) fixed
on the lower part of the lever 19 (Figs. 3 & 4).
Fig. 8. The action of the column is as follows:-
When the temperature of the surrounding matter increases the tube 7 expands in
length towards its lower end, which is free. The column 1-2 will then descend
under the pressure of the helical spring 10. As soon as the rod 9 moves, the lever 19
will follow the movement because the helical spring 27 turns the spindle 16 on which
the lever 19 is. mounted. This movement, which is also made by the screw 21,
presses the needle 22 towards the conical cup 23, thus turning the spindle 25 of the
Bector 26, the pinion-wheel 29 and with it the indicating needle 31, travelling over a
dial divided in a suitable manner. When the temperature of the surrounding
matter decreases the tube 7 will decrease in length and raise the column 1-2 and
the rod 8-9 which will push the lever 19. By this upward movement the spindle 16
will revolve in the opposite direction and the needle 22 will be drawn back without
being able to lose contact with the conical cup 23 since the spring 28 obliges the
latter to follow the movement of the needle, thus causing the sector 26 to turn, and
with it the pinion 29 and finally the indicating needle 31, in a contrary direction to
the preceding case. It is therefore evident that this apparatus serves to mark
exactly the changes in the length of the tube 7, which are exactly proportional to
the change of temperatures, because the column 1-2 remains constant.
The regulating screw 4 the pivot screw 21 and the arm 24 on which the conical
cup 23 can be adjusted, are the three means of regulation.
Fig. 9. The action of the helix 40 is as follows:-
When the temperature of the surrounding matter increases, the tube 7 expands
in length, and since firstly the helix 40 is fixed at its lower end and secondly the
rotating rod 41 cannot drop because it is held by the tube 43, above the nut 42 it is
evident that the helix 40 will untwist. It will thus turn the rod 41 and with it the
small plate 45. The rod 46 will press upon the tooth 47 and will rotate the
sector 26 the pinion 29 and the indicating needle 31.

page_text: When the temperature decreases for the same reasons the helix 40 will twist up
and will rotate the rod 41 and with it the little plate 45 in the opposite direction.
The spring 27 will keep the rod 46 in continued contact with the tooth 47 and
this movement will be transmitted to the sector 26, the pinion 29 and the indicating
needle 31.
It is thus evident that the changes of temperature are altered into changes of
length of the tube 7 which by means of the untwisting and twisting-up of the
helix 40-are transmitted to the mechanism.
When the column 1-2 is used in connection with the mechanism of the Figs. 6 & 7
the arm 50 (Fig. 2) will press against the friction-wheel 51 or the friction wheel 51
will be kept in continued contact with the arm 50 by the spring 27.
When the helix 40 is used in connection with the mechanism of the Figs. 3 and 4
the helical cam 53, the pitch of which is calculated to suit the displacement
necessary to the lever 19, will press against the friction wheel 54, or the friction
wheel 54 will be kept in constant contact with the cam 53 by the spring 27.
In both cases the mechanism acts as above described.
Fig. 10. To use this apparatus for the measurement of high temperatures (from
1800 to 3000° C.) protection by the tube of iron 14 is insufficient. The apparatus
is.then enclosed in a plumbago shell 55 and the cavities 56 are filled with air or
powdered amianth.
The action is the same as above described. It must however be pointed out that
it is more practical to measure high temperatures by more indirect means, that is
to say a proportion is first established between the temperature at the centre of the
furnace and at any point in the masonry, at which point the apparatus is placed, so
that the apparatus when indicating for example a temperature of 2000° is only
exposed to a temperature of 1200° and so on. The indicating needle 31 is adjusted
to suit.
Fig. 11. To measure the temperature of the gases in a blast furnace the gases
are made to pass through plumbago, 57 with or without cavities, and provided
with passages 58 for the gases which,, through the plumbago 57 act upon the
-measuring apparatus.
It is evident that the apparatus must be regulated accordingly.
The apparatus described may be provided with electric signals to indicate pre-
determined temperatures.
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 :-
1st. A registering apparatus for temperatures based on the employment of mica
in combination with substances whose contractibility is equal to the expansion of
the mica, as earthenware, slate, or in combination with brass and steel in a helical
form substantially as described.
2nd. A registering apparatus for temperatures based on the employment of the
substances above mentioned; forming the superposed column 1-2 which by means
of the rod 8 and 9, operates on the mechanism consisting in principal of a lever 19
fixed to the spindle 16 which, in turning acts by means of the needle 22 on the
conical cup 23 and thereby on the sector 26 the pinion 29 and the indicating
needle 31 substantially as described.
3rd. A registoring apparatus for temperatures based on the employment of the
mica 38 between a helix of brass 37 and of steel 39 the untwisting and twisting of
which is communicated by the rod 41 to the sector 26 the pinion 29 and to the
indicating needle 31 substantially as described.
4th. A registering apparatus for temperature based on the employment of a
column 1-2 as described in combination with the arm 50 acting on the friction
wheel 51 or with a helix 40 acting by means of the spiral 53 on the friction wheel 54
substantially as described.

page_text: 5th. A registering apparatus for temperature as described above, serving to
measure the pressure of steam in boiler by the heat thereof, by causing the
indicating needle to travel over a suitable scale.
6th. A registering apparatus for high temperatures, in combination with a
plumbago shell 55, 57 substantially as described.
7th. A registering apparatus for low and high temperatures and for steam
pressure in a boiler, allowing the exact registration of the changes in length of a
copper tube, or tube of forged iron, steel or platinum by a column 1-2 or a helix 40
in combination with a rod 8 or 9 having an axial movement or of a rod 41 having a
rotating movement, acting on suitable mechanism substantially as described!
Dated this 19th day of April 1892.
WHEATLEY & MACKENZIE,
40, Chancery Lane, W.C., Agents.
WHEATLEY & MACKENZIE,
40, Chancery Lane, W.C., Agents.