Improvements in Automatically Regulating the Temperature of Malt and Hop Kilns and Indicating the same.
Year: 1885

page_text: Improvements in Automatically Regulating the Temperature of
Malt and Hop Kilns and Indicating the same.
I, HENRY JAMES HOGG KING of Newmarket near Stroud, Gloucestershire
Engineer do hereby declare the nature of my invention for IMPROVEMENTS IN
AUTOMATICALLY REGULATING THE TEMPERATURE OF MALT & HOP KILNS &C, to
be as follows:
This Invention relates to Improvements in the Method of regulating the Tem-
perature of Malt & Hop Kilns for which letters patent were granted to the present
applicant-Patent No 5274 1879. In cases where considerable power
is required
to move the ventilator either through distance from the source of power or other-
wise, the plans there described I still consider best, but where the ventilator can be
made to move easily or where great accuracy is not required, the following modifi-
cations from their greater simplicity possess advantages in many cases.
In order to make the ventilators move as lightly as possible I mount them on
knife edges or V centres, and where they are liable to be influnced by gusts of
wind or strong draughts or to rough useage of any kind, I put on a double locking
arrangement which prevents the ventilator being moved except through the
medium of the power working it. It consists of 2 pawls, connected with the
ventilator and pointing in opposite directions, both these pawls fall at the same
time, into a ratchet bar which is fixed to the frame carrying the ventilator. When
the power from the variation of temperature in the Kiln, is applied in either
direction to move the ventilator, it lifts one or other of these locking pawls out of
gear and allows the ventilator to move in the direction the power is acting.
Having thus made the ventilator to move with great ease, I couple it by a gab
ended rod to a lever, one end of which has a long slot in it (usually @ right angles
to the lever) in which slides the pin which carries one end of the gab rod and on
the side of this slot the degrees of temperature are marked.
The lever is centred on knife edges and the other end is coupled to the rod which
passes under the Kiln floor. As the expansion and contraction of this rod is very
small for slight changes of temperature to obtain more power one of my improve-
ments consists in useing 2 or more rods coupled together by levers which augments
the motive power in proportion to the number and length of the rods used. In this

page_text: way I obtain sufficient power to work the ventilators from the expansion and con-
traction of the rods alone. In cases where there is a supply of water a simple
modification may be made by allowing it to run slowly into a vessel which has an
opening in the bottom through which a small quantity of water always runs away.
If it runs in faster than it runs away the vessel becomes heavier & the ventilator
opens or vice versa, the vessel being attached to the ventilator As the water falls
it is guided to or diverted from the vessel by a small tube or divider which is
moved by the brass rod or regulator inside the Kiln.
The ventilator may also be worked by a segmental thermal ring composed of
2 or more materials securely fastened together this will alter in shape with
variations of temperature or a Bourdon tube or case like an Aneroid Barometer of
large dimensions if filled with a liquid sensitive to heat may be used if fitted up
under the Kiln floor, or the simple expansion of mercury or other liquid confined
in a close vessel under the Kiln floor may be used for working the ventilator or an
elastic fluid like air may be used, but in this case it is neccessary to eliminate the
error produced by variations in atmospheric pressure. This I do by placing the
bellous diaphram or inverted holder on which the elastic fluid acts in a vessel
which is sealed by a liquid or otherwise and in which a partial vacuum is formed
which is below that of any atmospheric disturbence The temperature may be
indicated outside the Kiln, by means of a pointer (such as in a pressure gauge)
indicating on a dial the temperature. The pointer being moved like the ventilator
in either of the above described ways. A continuous record of the temperature
may also be given by means of a pencil, tracing a line on a paper moved by clock
work and an electric bell can be rung when any given temperature is reached, by
the completion of an electric circuit in any well known way.

page_text: Improvements in Automatically Regulating the Temperature of
Malt and Hop Kilns and Indicating the same.
I HENRY JAMES HOGG KING of Newmarket near Stroud, Glostershire Engineer
do hereby declare the nature of my invention for IMPROVEMENTS. IN AUTOMATICALLY
REGULATING THE TEMPERATURE &C &c 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 Improvements in the Methods of Regulating the tem-
perature of Malt & Hop Kilns, for which letters patent were granted to the
present applicant No 5274-1879-and in order that my said Invention may be
properly understood I have annexed hereunto 2 sheets of Explanatory Drawings-
Figs. 1-2 & 3 sheet 1. show a plan, elevation and side view of a Malt Kiln, with
an automatic ventilator attached, and worked directly by the expansion & contrac-
tion of metalic rods stretched across the Kiln, close under the wire or tile floor.
1 in Fig. 1 is a metalic rod (which I prefer to make of brass) one end of which is
fixed to the front wall of the Kiln the other end is connected by V centres to the
wrought iron lever 2 which is centred in the joint 3. This is fixed to the back wall
of the Kiln 4 is a similar rod to 1 and is connected to the lever 2 in a similar
way. It however passes out through the front wall of the Kiln and is connected
with knife edges to the bell crank lever 5. On the end of this lever a heavy
weight 6 is fastened which takes up all slack and keeps the brass rods strained
up. It will now readily be understood that as the rods 1 & 4 expand or contract
by the variations of temperature under the floor of the Kiln, the lever 5 will rise
and fall, and it is this motion which is utilized to open & shut the ventilator 7.
This ventilator may be placed in almost any part of the Kiln, but I prefer to place
it over the fire as it is then subject to the same conditions of draughts of air as the
fire and further the cold air admitted to the Kiln through the ventilator falls by
virtue of its superior density and mixes well with the warm air as it rises from
the fire.
If preferred the air admitted through the ventilator, may pass directly over the
fire or the ventilator may be used as a damper to control the admission of air to
the fire and thus regulate the temperature of the Kiln.
The ventilator 7 turns on a steel rod 8 shown full size in Fig. 4 the ends 9 & 10
being vd and turning in the steel thimbles 11 & 12 which can be exactly adjusted
by the set pins 13 & 14. By these means the power required to work the venti-
lator is reduced to a minimum.
On the shaft 8 a lever 15 is fastened which carries a weight 16, which always
tends to close the ventilator.
The scale 17 on which the temperature is marked is connected to the short end
of the lever 15, on the opposite side of the centre to the weight and it is essential
in practice that the slide 18 which marks the temperature should be able to be set
at once to any point on the scale irrespective of the 'position of the lever 5.-It is
also hecessary that no undue strain shall be put upon the lever 5, which might
strain the brass rods. To effect these objects I use 2 or 3 arrangements to suit
15

page_text: varying conditions. One of these is shown in Figs 1-2 & 3 and some of the
details enlarged in Fig. 5.
The connecting rod 19 is made sufficiently heavy to overcome the balance
weight 16 so that when the end 191 comes on the pin 20, the ventilator opens &
when lifted off it closes. The top end of 19-193 is carried by the pin 21 on the
end of the lever 5 and as the lever rises & falls by variations of temperature in
the Kiln, it will thus open & close the ventilator Through the slot in the con-
necting rod at both ends the slide 18 can be moved about anywhere, without
straining the lever 5.
Fig. 6 shows another plan in which the connecting rod 24 is made gab ended it
being made sufficiently heavy to work the ventilator, but the pin slips up the side
of the gab if any undue strain is put upon it. Fig. 7 shows an arrangement for
working the ventilator, when it is obliged to be placed in a recess.
The connecting
rod 19 is coupled to the lever 26 and the outside end is weighted with a weight
27 which swings in the frame 28. If the ventilator end of 26 is pulled down the
weight 27 is lifted up and no undue strain is put on the lever 5.
Fig. 8 shows an arrangement in which a motive power other, than that of the
heat in the Kiln is used to work the ventilator.
30 is a tap through which a small quantity of water is set to run, this falls into
the funnel 31, to the lower portion of which the pipe 32 is attached, the whole
arrangement being centred @ 33.
35 is a projection on the slide 18 which catches the arm 33-As shown it is
pressing on the arm 33 and the water runs down the funnel 36 and into the tin 38.
The tap 39 at the bottom of the tin is set to run out say as fast as the tap 30-
The tin 38 will consequently get heavier and will overcome the weight 16 and the
ventilator 7 will open, but as the Kiln cools 35 will lift and the water will be
wholly or partially diverted into 37 with the result that the tin 38 becomes lighter
and the ventilator will begin to close again.
In the illustration given water is the motive power, but it will be readily under-
stood that any other liquid would do equally well or the heat from a gas jet or
flame of any kind, might be diverted in the same way the whole arrangement in
this case being inverted, so that the hot air would pass up through the tube 31 and
acting on the contents of a sealed vessel, like a gas holder or diaphram containing
say æther a great power would be @ once obtained to work the ventilator, with
most minute changes of temperature in the Kiln.
In fig. 9 an arrangement is shown for locking the ventilator in any position
which is advantageous to use, when the ventilator is very large or is subject to
strong draughts of air. 40 is one side of the ventilator frame, on which the rack 42
is a fixture. The pawls 43 & 44 which are attached to the ventilator, hold it in
a fixed position, till one of the pawls is lifted out by the arm 45, which then allows
the ventilator to move in the direction, in which the arm 45 moves.
Fig. 10 sheet 2 shows a plan of working the ventilator, by means of a thermal
ring 48 which consists of 2 metals (rivetted or soldered together or both) having
different rates of expansion such as iron & brass.-Any variation in temperature
causes the ring to alter in shape and work the ventilator through the bell
crank 49.
Instead of the ring 48 a Bourdon tube may be substituted, containing a liquid such
as æther fusil oil or alchoal, which boils at a low temperature and this produces
a pressure which alters the shape of the tube and will act on the ventilator the
same way as the thermal ring 48, or any other vessel which is sealed in any way
may be used. And which by the expansion or evaporation of a liquid or gas
contained therein may open the ventilator.—2 illustrations of this are shown in
Fig 11 & 12.
In fig. 11, air is the motor in Fig. 12 a liquid such as boiled oil-In both cases
the air vessel 50, and tube 70 are sealed by mercury. The vessel 50 being filled
with air expands,, as the Kiln becomes hotter and lifts the inverted holder 51
which dips into the mercury 5%.

page_text: The holder 51 is also sealed against any changes of atmospheric pressure by
means of the inverted tube 53 which also dips into the mercury 54, the rod 55
being connected to the ventilator.
Fig. 12 shows a tube under the Kiln floor filled with a liquid such as lindseed
oil which only boils at a high temperature-the tube 71 is also filled with the
same liquid to the level 72, below which the syphon portion of the pipe is filled
with mercury--as the liquid in the tube 70 expands it drives the mercury up
into 73 and lifts the plunger 74 which is connected by the rod 75 to the ventilator.
Fig. 13 shows a' method of indicating the temperature of the Kiln―It simply
consists of a dial 80 worked by the rod 81 which is in connection with the lever 5
and as the brass rod 82 expands or contracts motion is given to the dial pointer.
If a continuous diagram is desired, a pencil can be attached to the pointer or its
equivilent and a paper moved by clockwork will give a continous diagram in a
way so well known that it is not essential to describe it.
Having now particulary described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declair that what
I claim is
1st The use in Malt & Hop Kilns, of a metalic rod or rods, which by their
expansion & contraction by changes of temperature in the Kiln-work a ventilator
for automatically regulating the temperature of the Kiln, without the aid of any
other mechanical power.
2nd The use of more than one metalic rod placed under or in the Malt & Hops
of Kilns which by being worked in combinations of 2 or more, enable sufficient
mechanical power to be obtained to open and close the ventilator, with but slight
changes of temperature in the Kiln.
3rd The mechanical details shown in Fig. 4 for making the ventilator more
easily.
4th The locking arrangement shown in Fig. 9.
5th The mechanical arrangements shown in Figs 1, 2, 3 & 5, for connecting the
ventilator with the brass rods 1 & 4.
6th The mechanical arrangement shown in Fig. 6, for connecting the rod 4 with
the ventilator.
7th The mechanical arrangement shown in Fig. 7 for working the ventilator, the
special feature being the weighted rod 26.
8th The use of the arrangement shown in Fig. 8, in Malt & Hop Kilns in which
a liquid or gas may be diverted in the manner shown-& described-for working
the ventilator.
9th The use in Malt & Hop Kilns of the thermal ring illustrated in Fig. 10 for
opening & closing the ventilator.
10th The use in Malt & Hop Kilns of a vessel hermetically sealed either by
mercury or any other way, such vessel being filled with a liquid or gas, & which
by expansion and contraction or evaporation and condensation produced by
changes of temperature in the Kiln produce motive power to open & close a
ventilator for regulating the temperature and of which the Bourdon tube & the
arrangements described in Figs. 11 and 12 are illustrations.
11th Indicating the temperature of a Kiln by means of a pointer & dial as
shown in Fig. 13.