Improvements in Drawplate Ovens.
Year: 1893

page_text: Date of Application, 16th Dec., 1893
Complete Specification Left, 16th Oct., 1894-Accepted, 16th Mar., 1895
Improvements in Drawplate Ovens.
A communication from abroad by WERNER & PFLEIDERER, of Cannstatt,
Germany, Baking Engineers.
1, PAUL PFLEIDERER, of the Firm of Werner & Pfleiderer, 117, Queen Victoria
Street, London E.C., Baking and Chemical Engineers and Patentees, do hereby
declare the nature of my said invention to be as follows :-
The object of my invention is to effect improvements in the details of construction
and arrangement of attachments or appurtenances to the baking chambers and
drawplates and of the movable supports or rails on which the drawplates run in
and out of the oven or baking chamber, such as are described in the Specifications
of my several former Letters Patent No. 19506, 10019º¹, 12655", 11841"¹, 1462**
referring to ovens.
My invention consists in the first place :-
In the adaptation of caps or steam covers to the drawplates in such a way as to
cover in a more or less steamtight manner a large portion or the whole of the
baking surface (similarly to the mode in which in restaurants the dishes of meat &c.
are often covered) by suspending such steamcovers or caps inside the oven or
baking chamber or by binging or sliding them over the goods on the drawplates or
by lifting them on and off the drawplates outside when the latter are drawn from
the oven in order to produce a similar steaming effect to that obtained in ordinary
oyens by baking in or under closed tins or baking pans.
Secondly-In providing the baking plate or the rails or the oven door with a
suitable form of guide, or cam, or other attachment or device whereby the same
movement or motion which places either the plate, or the oven door or the rails in
position can be made to also automatically or simultaneously place the rails, the
oven door, the plate or steam cover in position; vertically or horizontally as may be
required.
Thirdly-In providing rails or plates with suitable legs or arms, having rollers
or castors, upon which they are conveniently supported, or from which they are
suspended without obstructing the space in front of the oven.
Fourthly-In fixing or uniting together such legged or armed rails supported
on their wheels or castors so that they inay form together a complete frame or
carriage by themselves, or, (where there is room in the bakehouse,) in fixing such
carriage to and making it part of the drawplate itself. And,
Fifthly: In the case of "deck" or "decker" ovens, in so curving or shaping
the legs or arms of such combined drawplates or carriages or of the folded, hingel
or telescopic rails as to pass by and clear each other and their plates without
diminishing the convenience of access by the attendants, to the several drawplates ;
by which means the drawplates of one deck may be moved in and out independently
from and simultaneously with their fellow drawplates and those of the other
decks; thereby greatly facilitating the necessary operations of "setting" and
'drawing" the batch.
Dated 16th December 1893.
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.

page_text: A communication from abroad by WERNER & PFLEIDERER, of Cannstatt,
Germany, Baking Engineers.
I, PAUL PFLEIDERER, of the Firm of Werner & Pfleiderer, 117 Queen Victoria
Street, London E.C., Baking and Chemical Engineers and Patentees, do hereby
declare the nature of my said invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:—
The object of my invention is to effect improvements in the details of
construction, and arrangement of attachments or appurtenances, to the baking
chambers and drawplates, and of the movable supports or rails on which the
drawplates run in and out of the oven or baking chamber, such as are described
in the Specifications of my several former Letters Patent No. 19,506, 10,019",
11,841, 12,655, and 1,462 referring to ovens.
And in order that my said invention may be particularly described and ascertained,
reference is hereby made to the accompanying drawings, in which similar letters of
reference indicate corresponding parts.
The manner in which I perform the first part of my invention is as follows:-
I provide the baking plate P with a groove all round, into which I fit a more or
less steam-tight cap Y, which entirely covers the baking surface. This cap Y is
provided with eyes, in which hooks can be inserted, and the whole can be lifted off
and on to the drawplate, when the same is outside the baking chamber, by a
suitable pulley arrangement for large sized ovens, as shown in Figs. 1 and 2 ; and
I prefer to provide the entire cap Y with suitable spyholes, to enable the man to
see the goods, without lifting off the cover itself. Or I construct the steam caps or
covers in sections, which can be slid away or removed by hand; or I hinge them to the
drawplate in the manner of hinged flap or flaps Yf which can be opened and shut
either by hand or by lifting tackle, as shown in Figs. 3, 4, 5 and 6.
For many purposes it is preferable to arrange the steam caps Y inside the baking
chamber, so that they either can be removed from the baking plate, by lifting them
off bodily, by means of a lever arrangement or lifting tackle, or only partially
lifted or hinged up, so as to allow the baking plate to be withdrawn from under the
cap as shown in Figs. 7, 8 and 9. Or I make the steamcap Y a fixture in the
baking chainber, and provide it only with a flap Yin front, by which I cover
the opening through which the baking plate P passes in and out under it, as shown
in Figs. 10 and 11. I sometimes construct the steam covers Y or N of wire gauze,
similarly to the screens or heat-buffer plates or diaphragms N described in my
Patent No. 146293.
I perform the second part of my invention, by so constructing the parts, links,
and gearing, and movably connecting them together, by any known device of levers,
cams, chains, and pulleys, racks and pinions, or other gear, in such a manner that,
when the attendant moves one part, the other or others is or are caused to
simultaneously perform their respective movement or movements; thus when the
attendant turns the hand-wheel H, or otherwise lifts or removes the oven door D,
the steamcap Y, or the flap Y upon it, moves open at the same time, so that he
may at once withdraw the baking plate P, unless the same is also connected with
the moving mechanism of the oven door, in such a manner that it is already set in
motion; or the oven may be constructed on my telescopic rail system, described
in 19,506 and 12,655, when the movement may first be communicated to the
rails, R' Fig. 7 or R" Fig. 12.
I perform the third part of my invention by providing the rails or plates R

page_text: and R which form the subject of my first claim in Patent No. 12,655" with
suitable legs or arms J, which I fit with rollers, casters, or wheels W1, Figs. 7 and 13,
so as to reduce friction and make them more easily movable, which is particularly
desirable when the device under the second head of my invention is employed.
"
In performing the fourth part of my invention, I sometimes unite the rails R
together in pairs, so that each pair forms a regular carriage frame R' R', which is
more or less independently movable. These telescopic carriages, or movable
railframes, R', R', when drawn out, take the place of the fixed railframes R, with
their fixed supporting posts C, (Figs. 7 and 8 of my Patent No. 12,655") which
fixed appliances obstruct the bakehouse, although the drawplates themselves are out
of the way in the oven. This drawback most particularly applies to the old
Wieghorst ovens built in decks, in which the rails R are supported upon posts C₁,
which are fixed in the bakehouse floor, even beyond the extreme line to which the
draw lates P are ever drawn out. In my new ovens, constructed on the "deck'
or "decker" system, I construct the above movable railfames or carriages, in
such a manner that they pass each other, and allow sufficient clearance between
themselves, as also for the baking plates of the different decks, Figs. 15 and 16, to
be drawn out and pushed in, each independently from all others, by building the
carriages of different gauge, i.e. their wheels are set at different distances, so as to
run on rails of different gauge; or I may suspend the upper rails from the ceiling,
so that the carriage, as it were, hangs by its wheels, which run on these additional
tram-rails, suspended from the coiling, while the lower rails or carriage may be
constructed to telescope in and out as in "single deck" ovens. In single deck
ovens the carriage wheels may be allowed to run on a good bakehouse floor without
rails, but in ovens with two or more decks I prefer, as almost indispensable, to
employ tramrails to guide at least one of the wheels, or to employ guide-rails
which will prevent the carriages of the various decks from colliding at any point of
their travel, and to secure the required passage or clearance between themselves
and their respective drawplates. The drawplates or baking plates P, I either
construct so as to move on the above described rail carriages R' R', in any of the
methods described in my former Patents (Figs. 13 and 14, No. 12,655º¹) as
employed in connection with the older forms of fixed or telescopic rails; or as
illustrated in Figs. 13, 14, and 15, of the accompanying drawings. But, in some
cases, where low cost and the utmost simplicity are essential, and where room is
available, I combine the baking plates P. with the carriages R' R', so as to form
each one a simple rigid carriage; but in this case, which makes an extremely simple
construction, I have the disadvantage that the front wheels W¹ W₁ of this
carriage R', R', P, come out in the bakehouse, when the plate is drawn out, even
farther than the extreme ends of the bakingplate itself, when constructed in any of
the old methods; but the remaining advantages are still considerable, because,
when the baking plate P is in the oven, the space in front is almost free. The
difficulty may be overcome by running the whole plate and carriage R¹, R', P,
entirely into the oven or baking chamber; but this plan is very objectionable and
is not of my invention.
In order to further facilitate the understanding of the drawings, the following is
a separate description of the several figures: =-
Figs. 1 and 14 show a drawplate with cap Y. In Fig. 1 the hooks of the lifting
tackle are hooked into the eyes of the cap ready for lifting the same bodily off the
drawplate. Fig. 2 shows a cap Y, hinged to the drawplate, and, in dotted lines,
the two halves of the cap are shown as hinged up by overhead tackle. Figs. 1^
and 24 may be regarded as front views of Figs. 1 and 2 respectively, but they also
serve as illustrating, by a sectional view, how the chain of the lifting tackle may be
passed through the roof of the oven, and the cap lifted off and put on its drawplate
inside the oven chamber. Figs. 3, 4, 5, and 6, illustrate the construction of
sectional caps or covers Y', which can be flapped on or off by hand. Figs. 7, 8
and 9 show the construction of pivoted caps Y inside the oven, which are lifted or
hinged up from outside, so as to allow the baking plate to be withdrawn from under

page_text: the cap. à' is a hinge or fulcrum axle carrying the end of cap Y loosely, and
so that the cap can be removed from the oven with comparative ease, by dragging
it out with the drawplate.
The carriage frame R', R', being composed of the rails R¹, supported in front on
legs J, running on wheels W1, is supported in the oven on an axle a, which runs
with its wheels W on fixed rails R inside the oven. The baking plate P travels
as a fixture with, or movable upon the carriage R' R'. The ends of the rails
are formed into tooth racks, and pinions z¹ are mounted in front of the oven
mouth, in such a manner that they gear into these racks, when the carriage is in
either of its extreme positions, out of which therefore it can be easily moved by
turning a handle applied to the axles of the pinions . An arm fixed to the
oven door lifts up the cap by the same movement hy which the attendant lifts the
oven door. In Fig. 8 the lifting of the cap Y, is effected by a lever arrangement
mounted on an axle a³, and counterbalanced by weights c¹.
The position of the cap Y and the lever arrangement, as it appears when the cap
is lifted off, is shown in dotted lines, a small flap y' is shown to be fixed on an axle
passing through rails R'; this flap closes the drawplate in front, and the cap Y,
when lowered down, holds the same in position. Fig. 9 shows the cap Y, balanced
and suspended from chains & passing over pulleys fixed to the ceiling, and
carrying counterweights in front of the oven by means of which the device can be
actuated. Fig. 10 shows a longitudinal section through an oven with a cap Y¹ Y'
fixed in the oven-chamber. The drawplate P in this case is provided with a
hinged flap Y, which closes the cap when it is hinged up, after the drawplate is
pushed right into the oven. The drawplate runs over the carriage-frame R', R',
on a pair of rollers constructed on the principle described and illustrated by
Figs. 13 and 13 of my Patent No. 12,655. R are the fixed rails in the oven,
and S are the Perkins pipes by which it is heated; fare flues affording means of
circulation of the heated air, the steam-cap being in this case built in the wall as
shown in the cross-section Fig. 11. qy are angle irons fixed to the wall underneath
the drawplate, so as to trap to some extent the steam-cap or steam-chamber.
Fig. 12 shows one of my combined multiple-deck draw-plate steam-ovens, partly
in section and partly in elevation, showing the furnace wall as seen from the stoke-
hole. In the lower two decks, two kinds of drawplate arrangements are shown;
on the left-hand side my improved lath-plates are shown in dotted-lines protruding
from the oven-mouths in position to deliver the baked goods on platforms or tables
standing in front; on the right-hand side an arrangement of rails is shown, in
which the bottom represents ny ordinary telescope rails K, fixed, and R" tele-
scoping in and out between the fixed rails R. The upper-deck rails are constructed
so as to fold out of the way entirely, R" R" leaning up against the oven-front;
R their legs folded or hanging down. The dotted lines show this arrangement
hinged down in position, and the drawplate drawn out upon it. lu the two upper
decks in which the drawplates run parallel with the heating-pipes, the lower ones are
shown fitted with steam-caps Y, and the upper ones with screens N. An arrange-
ment is shown by which these screens N are suspended and made adjustable so as
to be approachable to or withdrawable from the top of the goods in the oven.
Fig. 124 shows, on a larger scale, a drawplate which is suitable to work without
any rails or railframes in the bakehouse; being a modification or combination of
the two features of divided plate A and B, and lath plates Z, forming the subject-
inatter of my Patent No. 19,506. The waggon drawplate Z is so balanced that
it can be drawn out of the baking chamber about one-half of its depth, the front
part, PA, of the baking-surface I generally make immovable, the back part, PB,
I construct so as to slide forward over PA, by means of the chain attachments shown.
The chains t, in this case, are attached to the end of PB, and by means of a
handle put on the square end of the axle A, the chain wheels are caused to drag
the back half PB, forward or backward, by means of the endless chains t. The
Fig. 124 shows the baking surface extended; if it is now pulled out of the baking
chamber, the handle applied, and PB dragged forward, after having first cleared P*,

page_text: When
it can be filled with dough-loaves, h is now turned the reverse way and PB dragged
i its hindmost position. Now PA is set with bread or other goods to be baked,
and the entire plate, with its frame or carriage Z, is pushed into the oven.
the goods are baked Z is withdrawn (about of the depth of baking surface only)
PA is emptied of its baked goods, 1B dragged forward, also emptied and filled or
covered again with fresh goods; the space required in front of the oven being
reduced to about one half of the usual depth, and no encumbrance left outside
during baking.
Fig. 13 is a perspective view showing the carriage-frame R' R', and the movable
drawplate P, as far in the oven-chamber as they will go. The rails R¹ R' are
connected in front by a cross-piece, and the legs J, are firmly connected by the axle
on which the front wheels W' revolve.
Fig. 14 shows in detail how the frame-carriage R' R' is supported in the oven
behind upon the rolling friction axle X, with wheels W, which run on the fixed
rails R in the oven. The baking-plate or draw-plate proper, P, runs on anti-
friction rollers r, which roll on the rails R', and support the drawplate on their
extreme ends or pins p. The supporting rails or irons b, which run on or roll over
these pins p, have stops, so as to push the rollers r in parallel line at every end-
position of the drawplate, should they have got out of parallel.
With this
arrangement the carriage R', R', need not run out into the bakehouse more than
about of the whole depth of the drawplate, while the latter can nevertheless be
withdrawn for its whole depth, and the oven-door closed behind it.
Fig. 15 shows a two-deck oven with the lower rails fixed and projecting a little
over one half from the oven-mouth. The lower drawplate runs out ou them,
bearing with its antifriction roller wheels against the inner edges of the rails, while
the upper drawplate is constructed similarly to that of Fig. 13, and its carriage
runs with its wheels W₁ bearing against the outer edges of the same rails R, and
keeping a clear space for the lower drawplate to pass freely between its legs J;
also the door of the lower oven flaps opens and clears between the legs J, J, and
wheels W, W, of the carriage-frame R¹, R', of the upper drawplate. The oven-
doors in this case are constructed as flaps suitably counterbalanced by weights,
which keep them in their extreme positions. In order to illustrate the principle
clearly, the side of the oven-chamber and furnace is supposed to be cut away.
Fig. 16 shows a perspective view of a two-deck-oven, constructed according to
the last part of my invention. The lower draw plate P, which is a fixture on its
carriage R', R', with its legs J, J, and wheels W, W', is drawn out of the oven
entirely, and the door is closed; at the same time the upper drawplate with its
carriage is partly drawn out, to show how the same clears both the lower drawplate
and its carriage. The figure shows clearly how the carriages run independently on
rails of different gauge.
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 :-
1. The application as described of steamcaps or covers to fit over the goods on
the drawplates.
2. The making interdependent two or more movements of various parts of draw-
plate ovens as described.
3. Providing the arms or legs of movable rails with auti-friction wheels or casters
which remain always either outside or inside the baking chamber and which when
such rails are drawn out or swung into position safely support the baking plates
drawn out upon them.
4. Combining or fixing together in pairs R' R' the telescopic rails for supporting
the drawplates which run over them and providing them with wheels or rollers or
casters W&W which run on the floor of the bakehouse directly or on rails and
which, with that part of the frame or carriage to which they are attached, remain
always either outside or inside the baking chamber.

page_text: 3. In deck or decker drawplate ovens the telescopic rail carriages the upper ones
with curved legs as described clearing and passing by each other as well as by each
others' baking plates either with baking plates movable on them or with the baking
plate or plates fixed on them.
6. The general construction and the several and respective arrangements and
combinations of parts together constituting my invention of improvements in
drawplate ovens more particularly of the systems forming the subject-matter of my
previous Patents.
D1 L
1004
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.