IMPROVEMENTS IN OVENS FOR BAKING BREAD OR OTHER SUBSTANCES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE FOR DRYING, ANNEALING, AND OTHER ANALOGOUS PURPOSES
Year: 1859

page_text: LETTERS PATENT to William Sellers, of Philadelphia, in the State of
Pennsylvania, one of the United States of America, Engineer and
Machinist, for the luvention of "IMPROVEMENTS IN OVENS FOR BAKING
BREAD OR OTHER SUBSTANCES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE FOR
DRYING, ANNEALING, AND OTHER ANALOGOUS PURPOSES."
Sealed the 7th October 1859, and dated the 10th June 1859.
PROVISIONAL SPECIFICATION left by the said William Sellers at
the Office of the Commissioners of Patents, with his Petition, on the
10th June 1859.
I, WILLIAM SELLERS, of Philadelphia, in the State of Pennsylvania, one of
the United States of America, Engineer and Machinist, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN OVENS FOR BAKING BREAD
OR OTHER SUBSTANCES, WHICH IMPROVEMENTS ARE ALSO APPLICABLE FOR DRYING
ANNEALING. AND OTHER ANALOGOUS PURPOSES," to be as follows:-
The object of my Invention in the construction of baking or annealing
ovens is, first, to make the oven of such form, that with a given number of
cubic feet inside it will contain the largest amount of material to be operated
upon.
Second, to so arrange the moving parts that they shall nearly balance
each other, thus requiring but little more power to operate them than is
necessary to overcome the friction and inertia of the machinery.
TD 077

page_text: Third, to arrange the machinery for entering and discharging the
materials, so that its operations may be continuous, fresh material being
put in as that which is finished is discharged.
Fourth, to make the reception and discharge of the materials automatic;
the periods when such operations are to take place being determined by
machinery, which can be adjusted to longer intervals of time, but when
adjusted, all the movements of the oven shall be in accordance therewith.
Fifth, to so arrange the machinery of the oven that the movements which
are necessarily intermittent may be performed in the shortest possible time
without any shock or jar, and so that the speed of any one movement may
be increased or.diminished without thereby affecting any of the others.
Sixth, to place the fire inside the baking chamber with a suitable
arrangement of flues and charging and discharging doors whereby all the
deleterious products of combustion will be prevented from coming in con-
tact with the materials to be baked or annealed, whilst in this process I
make use of radient, reflected and transmitted heat.
Seventh, to use the waste heat as it passes from the oven to generate
power for the purpose of operating the moving parts of the oven or other
machinery required in the manufacture of the raw materials, whilst by a
suitable arrangement of flues more or less of this heat may be used without
sensibly affecting the draught of the fire or otherwise altering the heat of
the baking or annealing chamber.
Eighth, to provide a means of cooling off the oven, so that in this process
none of the products of combustion in the furnace shall pass into the baking
chamber.
The principal features of novelty in my present improvements consist,
first, in arranging the cars or pans in which the articles or materials to be
heated, baked, or annealed, are placed, in the ovens, one above another in
such a manner that the cars or pans of the pile or series shall rest and
depend upon each other for their support or motion
In combination with this arrangement of the cars or pans there is a
suitable mechanical arrangement whereby a car or pan can be withdrawn
from either end of the pile or series without disturbing the remainder,
which are supported while the car or pan intended to be removed is with-
drawn from the pile and another one brought forward in its place.
Another important feature consists in arranging the cars or pansin ovens in
two piles or series, so that one pile may counterbalance the other, and all the
cars may be conducted in succession through the oven. In combination with
this double pile or series of moveable cars or pans, the mechanical contrivance

page_text: for moving the cars in or out is arranged in such a manner that a single car
may be transferred from either end of one of the piles or series to the same
end of the other pile or series, thereby causing the car to make the circuit of
the oven during the baking or annealing process, and to allow it to enter and
be discharged at one and the same door, so that only one door to the oven
is required.
The mechanical contrivances whereby the working parts are actuated
consist of a vibrating beam or beams with suitable connecting rods attached at
their opposite ends to levers or other equivalent contrivances, whereby an
intermittent motion is communicated to the pile or piles of cars or pans, and
to such single cars or pans as may require to be transferred from the exterior
to the interior of the oven, or vice versâ, or from one pile to the other in their
circuit through the oven. These mechanical parts may be actuated by hand
or by the opening or closing of the open door, but I prefer the action of the
parts should be automatic, and for this purpose motion is communicated to
them from the pistons of hydraulic cylinders conveniently disposed or
arranged as regards the other parts of the apparatus.
An important feature of this part of the Invention is, therefore, the use of
water, oil, or other non-elastic fluid under pressure, and made to operate upon
plungers or pistons to produce the motions required.
The valves whereby the passage of the water or oil into and out of the
hydraulic cylinders is controlled, and the requisite motions of the several parts
is regulated, are connected with some parts of the mechanism which has a
continuous motion, so as to be operated at regular and proper intervals of time
for the purpose specified. The action of the water, oil, or other non-elastic
fluid under pressure and operating upon plungers or pistons in the hydraulic
cylinders is so arranged as to produce the motions required in consecutive
order, so that at or after the starting of the first motion of the series, the
valves controlling the various subsequent motions shall be operated at the
proper time by some motion of the series until the whole are completed.
Another improvement consists in adapting to the automatic apparatus,
whereby the cars or pans are passed through the oven, a clock, alarum, or
other instrument for measuring time, this instrument is connected with a
trigger, click, or catch, that forms part of the machinery which operates the
oven, and by relieving or setting free at stated intervals the said click, catch,
or trigger, the other machinery will be set in motion at the proper period for
the purpose of eutering or discharging the materials to be baked or annealed.
This clockwork or alarum may, if required, be so arranged as to admit of the
intervals or periods at which the automatic machinery is to be set in motion,

page_text: being regulated as desired, so as to render the oven capable of heating,
baking, annealing, or operating upon articles or materials of different kinds.
Another feature of novelty consists in connecting a steam boiler, or air, or
gas engine with the oven in such a manner that the heated gases from the
oven may be discharged in contact with the same, so that the heat may be
economized by being applied to some useful purpose, such as heating the
water in a steam boiler, or the air or gas in a motive power engine. By this
means motive power to drive the working parts of the apparatus may be
economically obtained, and the waste heat from the oven usefully employed.
The oven is heated by a furnace below, and the heat and gases therefrom are
conducted through a series of flues, conveniently arranged inside the oven, so
that a portion of the heat as it passes along the flues will be radiated there-
from and made to heat the oven, while the remaining portion of heat will be
conducted away and usefully employed as above mentioned.
In order to cool down the oven, other flues provided with dampers are
adapted to the oven; and by driving cold air into the oven by means of a fan
or blower actuated from any suitable part of the driving machinery, the warin
air will be driven from the oven into the open flues and the oven quickly
cooled down.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Sellers in the Great Seal Patent Office on the
10th December 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
SELLERS, of Philadelphia, in 'the State of Pennsylvania, one of the United
States of America, Engineer and Machinist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of June, in the year of our 'Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Sellers Her special license that I, the said William
Sellers, my executors, administrators, and assigns, or such others as I, 'the
said William Sellers, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times
thereafter during the term thereinexpressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and

page_text: Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN OVENS FOR BAKING BREAD OR OTHER SUBSTANCES, WHICH IMPROVEMENTS
ARE ALSO APPLICABLE FOR DRYING, ANNEALING, AND OTHER ANALOGOUS PURPOSES,"
upon the condition (amongst others) that I, the said William Sellers, by
an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Sellers, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawings hereunto annexed, and to
the letters and figures marked thereon (that is to say):-
-
The object of this Invention of improvements in ovens for baking bread
and other substances, relates to a novel mode of constructing baking or
annealing ovens, whereby ovens are made of such form that with a given
number of cubic feet inside, they will contain the largest amount of
material to be operated upon.
The Invention consist, secondly, in so arranging the moving parts that
they shall nearly balance each other, thus requiring but little more power
to operate them than is necessary to overcome the friction and inertiæ of
the machinery.
The Invention consists, thirdly, in so arranging the machinery for entering
and discharging the materials that its operations may be continuous, fresh
materials being put in as that which is finished is discharged.
Another improvement relates to a means of making the reception and
discharge of the materials automatic, the periods when such operations are
to take place being determined by machinery, which can be adjusted to
longer or shorter intervals of time, but when adjusted all the movements
of the oveu shall be in accordance therewith.
The next improvement consists in so arranging the machinery of the oven
that the movements which are necessarily intermittent, may be performed
in the shortest possible time without any shock or jar, and so that the
speed of any, one movement may be increased or diminished without
thereby affecting any of the others.
.117.:.
The sixth improvement consis's in placing the fire inside the baking
chamber, with a suitable arrangement of flues and charging and discharging
doors, whereby all the deleterious products of combustion will be prevented

page_text: from coming in contact with the materials to be baked or annealed, whilst
in this process I make use of radient, reflected and transmitted heat.
By the seventh improvement the waste heat as it passes from the oven is
used to generate power for the purpose of operating the moving parts of the
oven or other machinery required in the manufacture of the raw materials,
whilst by a suitable arrangement of flues, more or less of this heat may be
used without sensibly affecting the draught of the fire, or otherwise altering
the heat of the baking or annealing chamber.
The eighth improvement relates to a means of cooling off the oven so
that in this process none of the products of combustion in the furnace
shall pass into the baking chamber.
The plan which the Inventor of the present improvement has adopted to
accomplish the aforesaid objects is shewn in the accompanying Drawings,
in which Fig. 1 is a plan view, and Fig. 2 a horizontal transverse section of
an improved oven; Fig. 3 is a vertical longitudinal section of the same as far
down as the fire doors, when it becomes a side elevation, shewing also the end
of the boilers for generating steam to drive the machinery; Fig. 4 is a vertical
transverse section, and Fig. 5 is a front elevation.
A, A, Figs. 2, 3, and 4, is the baking chamber, which is made in the form
of a parallelogram, so as to correspond in shape with the two tiers of cars or
pans B, B, B, B. These cars are provided with wheels for the purpose of
entering and discharging them; the upper side of each car is flanched to form
à rail on which the wheels of the car next above can run. They are placed
in the oven to any height that may be found desirable, each car resting on the
one below it except the bottom one, which rests alternately on the pawls and
rails as herein-after described. To maintain the cars in a vertical position and
to sustain the rails, pawls and other machinery for entering and discharging
the cars, six iron beams C, C, C, C, are provided, and are joined together
longitudinally by the bars a, a, a, a, and transversely by the beams C', C, C¹,
'the whole forming a frame which is sustained and attached to the outer
framework A¹; A', by the bolts b, b, b. The lower end of this frame C, C, C,
carries the rails 6, 6, which supports the cars B, B, B, as they enter and leave
the baking chamber as far as the centre beam C. Resting on the outer frame-
work A', A', are two supports or journals B1, B', carrying the vibrating beam
D, D, to arce, on which by means of link chains and bolts, are attached eight
iron beams D', D1, D2, D2. These beams are jointed together at top and
bottom so as to form two separate frames D', D¹, and D2, D3, capable of
playing freely up and down inside the frame C, C, C, C, a distance of half an
inch more than the car B, and at the lower end of the frame D2, De, are rails

page_text: de, d, on which the cars B, B, are supported as they enter and leave the
baking chamber after passing from the rails 6, 61, in the frame C, C, C, C.
At the lower end of the frame D', D', are rails d', ', which support the cars
B, B. upon their axle bearings, and lower them upon the rails 6, 1, for the
purpose of being discharged from the baking chamber. To the frame C,C,C,C,
are attached the rail pawls e, e, e, e, which support the cars B, B, when not
resting upon the rails d', d, d², 2, 2, or 1, b. Motion is communicated to the
frames D', D, and D2, D2, through the vibrating beam D, by means of water,
oil, or other non-elastic fluid operating upon the piston in the cylinder E, causing
the piston to ascend or descend as this fluid is admitted to one or the other end
of the cylinder, and moving the bean D, by means of the cross head E¹ and
connecting rods f,f. The cross head serves also to operate the rail pawls e, e,
el, el, having on each end a projection which strikes the tail of the levers f,f",
and causing them to raise the weighted levers g, gl, which are attached to the
rail pawls, as shewn in Fig. 4. The shafts connecting the weighted levers y, g',
Fig. 4, with the rail pawls are supported by the frame C, C, C, C. The rods
connecting the leversf, f, with the weighted levers g, gl, are provided with
an opening at the levers g, g, equal to the amount of movement which this
rod can have, and in this opening pins in the levers g, g', work; this is for the
purpose of allowing the levers g, g', to remain-up, whilst the rods which raised
them makeanother downward stroke, and enabling one rod to work both levers,
one being at rest whilst the other moves. The levers f. f, are each provided.
with one tail piece, which serves to raise them by means of the cross head E¹,
and with another at the same end which serves to hold it up by means of the
spring catch h, h, as shewn in Figs. 3 and 5. The cars are entered and
discharged from the oven by means of the sliding stop or pin ', Fig. 4, which
slides in a guide supported by the frame C, C, C, C. The pin his operated by
means of a wire rope or chain to which it is attached, one end of which is
fastened to the wheel F, and the other passes over the carrying wheels F. E,.
at the back of the oven, and is attached to a weight shewn in Fig. 3, which
serves to take up any wear or expansion from heat.
The wheel F carrying with it the chain and pin his operated by means.
of the rack G and pinion H, and motion is communicated to the rack G by
fluid under pressure in the cylinder I operating upon the plunger j. The car
at the top of the back pile or series is transferred to the top of the front pile.
or series, by means of the hook on the end of the rack K, which rack is
operated by the wheel K' on the shaft %, the other end of which carries the
pinion H gearing into the rack G; which operates the sliding pin ', as before
described; so that the operation of transferring the top car of the back pile or

page_text: series to the top of the front pile or series, is performed simultaneously with
that of entering a car into the oven. L is the door of the oven which is opened
and closed by fluid under pressure being admitted to or discharged from the
cylinder L and M. is a frame outside the door to receive the cars as they are
discharged from the oven, and on which the rest while being reloaded.
i
As
the cars are discharged with their load of baked materials, it is necessary to
provide a means of unloading them quickly, and this is done by attaching the
frame M to the shaft 1,, which is supported in journals m, m, fastened upon
the outer frame A1,A¹. To the outer end of the shaft 1,,is fastened an arm 1, 1,
which is operated from the cylinder N through the cross head, and connecting
rods shewn in Fig. 5.
As fluid is admitted or discharged from this cylinder,
the frame M is turned up so as to discharge the contents of the car, or it is
left horizontal, as shewn in the Drawing, ready to receive a fresh load. The
operating fluid is admitted to the cylinders, in which it acts by means of valves,
which may be of various forms; they should be of the character known as
slide valves, and any of them in common use that can be nearly balanced will
answer the purpose. The pressure required may be obtained from a column
of water, but I prefer to use oil taken from an accumulator, weighted to the
proper degrec, and supplied by force pumps, as it is used by the oven,the same
oil being worked over and over with very little loss. A clock of the character
called alarm, is placed in the position shewn in Fig. 5, and must be so arranged
as to set off at longer or shorter intervals as may be desired, and in place of
starting a bell, as is customary, the setting off must liberate the hair trigger t,
with which it is shewn in connection.
Havingthus described the various parts of the machinery of the oven, I will
now proceed to explain the mode of operation. Supposing the machinery to
be in a state of rest, and the car on the outside of the door ready to be loaded,
as shewn in Figs. 1, 2, and 3, the position of the several parts will be as
follows The rack cylinder I, Fig. 5, is full of oil, and the rack is up. The
cylinder L', which works the door 1 is empty, and the door L is down, as
shewn by dots in Fig. 5. The vibrating beam cylinder E is supplied with oil
below the piston, and the cross head E' is up. The tipping cylinder N is
empty. The back pile of cars is resting on the pawls e, e, and the rail is down
ready to receive the car from the outside. The front pile of cars is up and
resting on the rail d', d', and the pawls e, e¹, have fallen out of the way.
The clock liberates the hair trigger t,Fig. 5 of the door cylinder L',when the
valve opens by pressure of oil on the stem; the door L in going up strikes
a bell crank, the front end of which is shewn at.u in Fig. 5, and is attached to
the valve of the rack cylinder I, This bell crank as it works, pushes over the

page_text: valve for exhausting the cylinder I, and allowing the rack to descend. When
this takes place, it pulls the car into the oven over to the back side, and also
pulls the top car of the back pile on to the top of the front pile. As the rack
descends (when nearly at the bottom of its stroke) a stop 1, Fig. 5, on its side
strikes and passes the bell crank of the valve of the cylinder E, thereby moving.
the valve over, and exhausting the bottom end of the cylinder, and giving
water on the top of the piston, thus depressing the cross head, and lifting the
car just entered until it strikes and lifts the whole of the back pile. As soon
as the weight of the back pile is taken off, the rail pawls e, e, they fall away,
being moved by weight of levers g, g, and the bottom car passes above them.
The front pile of cars descends at the same time that the cross head descends,
and as the cross head nears the bottom of its stroke, it strikes the levers f¹, f¹³,
attached to pawls, thereby drawing the pawls into place under the bottom of
the lower back car, and under the bottom of the top flanch of next to lower
car of the front pile, and by thus arresting the front pile it allows the bottom.
car to descend half an inch free. The cross head when near to the bottom of
its stroke also pushes down a long rod o, Fig. 5, which is attached to a
balanced lever pgoverning its own valve, thus gradually stopping its descent
as the valve closes; it also brings the bell crank into proper position to be
struck by the stop 2 on the rack, the stop which had moved it in the first
place having passed again without moving, these stops being hinged to the rack
in such a manner as to give motion only in one direction. This long rod o
also pushes down the lever of the valve of the rack cylinder, thereby opening
the valve and giving oil to this cylinder and sending the rack up, thus forcing
the bottom car of the front pile out on to the tipping frame M and running
the top horizontal rack over into gear with the top back car. The rack when
nearly up, strikes by the stop 3 and passes the bell crank of the door
cylinder L', thereby moving the valve over shutting door, and resetting the
hair triggert, it strikes also with the stop 4, the bell crank of tipping cylinder N,
thereby moving the valve open and tipping the car. The ascending rack also
causes the stop 2 to strike the bell crank of the valve of the cylinder E,
thereby giving water in the lower end of the cylinder by moving the valve over.
The cross head now ascends, and passing up a short distance, say six inches,
strikes the springs h,h,and liberates the levers which held the pawls under the
cars; these levers fall back, but the pawls remain in position under the cars
as there has been motion enough to bring the weight of the back pile on to the
pawls, and the front one is already resting on its pawls. As the cross head
continues to ascend, it will, when near the top of its stroke, lift up the front
pile, thereby freeing it from the pawls, which will fall away; and, lastly,

page_text: the cross head, by striking a stop on the long rod o, will lift it up, moving
its own valve slack off, and stop as before, and at the same time will move
the valve of the cylinder N, causing it to be exhausted and bring up the
car, thus leaving everything as when the first movement commenced.
By altering the size of the opening in the valves that admit the fluid to the
cylinders, the speed of each part may be varied without thereby affecting any
of the others, and great speed may be attained in each part without shock
or jar.
In order to apply the heat to the oven, the fire is placed immediately below
the baking chamber, as shewn in Figs. 3 and 4, the flues R, R, for carrying off
the gases having their openings below the door of the baking chamber, so that
none of the deleterious products of combustion can enter this chamber, and it
becomes unnecessary to have a tight partition between the fire and the baking
chamber. I prefer making the flues of cast iron joining the vertical ones to a
large horizontal one S on each side by means of sand joints, the lower end of
the vertical flues resting on the side of the oven, the joint allowing sufficient
for expansion and contraction. The two horizontal flues are carried down at
the back of the oven, as in Fig. 2, and are jointed together at the bottom
when they can either pass under the boiler, through the flue P, or into the
main chimney by the flue Q, Fig. 3, its passage either way being controlled
by dampers. In order to cool down the oven rapidly, there are two pipes T, T,
Fig. 1, having dampers in them which are placed over the top of each series or
piles of cars; these pipes are converted with a fan operated by the machinery
of the manufactory which will force a current of cold air into the oven, aud
drive the warm air into the flues until the requisite temperature is obtained.
Having thus fully described this Invention of improvements in baking
bread or other substances, I would observe that it will be evident that the
Invention may also be employed for drying, annealing, and other analogous
purposes, I therefore reserve to myself the right of applying the Invention to
such purposes, and I claim as new and desire to secure by Letters Patent,-
First, arranging the cars or pans in ovens one above another in such a
manner that the cars or pans of the pile or series shall depend upon each
other for their support or motion when this is combined with any mechanical
arrangement whereby a car or pan can be withdrawn from any end of the pile,
or series without disturbing the remainder.
Second, arranging the cars or pans in ovens in two piles or series, one pile
or series having an ascending, and the other a descending motion; when this
is combined with any mechanical arrangement, whereby a car may be trans-
ferred from either end of one pile or series to the same end of the other pile or

page_text: series, thereby causing the car to make the circuit of the oven during the
baking or annealing process, and to allow it to enter and be discharged at the
same door.
Third, the use of water, oil, or other non-elastic fluid under pressure, opera
ting upou plungers or pistons, to produce the motions required, the valves
controlling these motions being so connected with some continuous motion as
to be operated at regular and proper intervals of time.
Fourth, the use of water, oil, or other non-elastic fluid under pressure,
operating upon plungers or pistons to produce the motions required, these
motions being so arranged in series that at or after the starting of the first
motion of the series, the valves controlling the various subsequent motions
shall be operated at the proper time by some motion of the series until the
whole are completed.
Fifth, the adaptation of a clock or other instrument for measuring tiine to
the machinery which operates the oven, so as to set the same in motion at the
proper period for the purpose of entering or discharging the materials to be
baked or annealed.
Sixth, connecting a steam boiler or air or gas engine with the oven in
such a manner that the heated gases from the oven may be discharged in
contact with the same.
In witness whereof, I, the said William Sellers, have hereunto set my
hand and seal, this Eighth day of October, in the year of our Lord
One thousand eight hundred and fifty-nine.
W. SELLERS. L.S.)