Improvements in Drawplate Continuous Baking Ovens.
Year: 1890

page_text: Date of Application, 29th Nov., 1890
Complete Specification Left, 22nd Aug., 1891-Accepted, 17th Oct.. 1891
PROVISIONAL SPECIFICATION.
Improvements in Drawplate Continuous Baking Ovens.
A communication from Messrs. WERNER & PFLeiderer, in Cannstatt,
Germany, Engineers.
I PAUL PFLEIDERER of 86 Upper Ground Street Blackfriars Road London E.C.,
Engineer do hereby declare the nature of my said invention to be as follows:-
In the continuous baking ovens with drawplates (travelling baking plates) those
drawplates hitherto in use are of a size to cover the entire area of the oven bottom,
that is to say, of the bottom of the baking chamber when they are pushed into their
baking chambers, consequently they occupy when drawn out an equally large area
in the bakehouse in front of the oven.
This circumstance coupled with the necessity of having to fill the whole plate
with great rapidity with the dough loaves (setting the bread on the plate) in order
to obtain good results, prevent many bakers from adopting drawplate ovens however
great their other advantages may be.
These objections I remove in the first place by sub-dividing the total area into
sections that is to say by constructing a number of small drawplates to draw out
one at a time and telescoping them as it were one over the other and one by the
side of the other. This I bring about by arranging and mounting the wheels on
which the drawplates run in and out of the oven in such a manner that the draw-
plates farthest in the oven are the widest and allow the next ones to pass in under.
thin plates and between their wheels and so on, always the hindmost in the oven to
be large enough to allow it to pass out over the plates in front of it, so that, when
all the small sectional drawplates are pulled out of the oven they occupy only the
area corresponding with that of the hindmost or largest one, so that, supposing⚫
the oven plate were divided into three sectional plates each of one third the total
length they would when drawn out occupy at most one third of the space which the
whole plate would occupy were it not so divided.
One further sub-division lengthways which would for instance divide the above.
three sectional plates into six-but it would not result in any greater economy of
room in front of the oven, because space will always have to be provided for the
entire aggregate width of the whole baking plate. Such sub-division lengthways
is therefore only useful if the smallest possible area of baking plate is desired at
any one time to be out of the oven, but for this purpose such sub-division may be
carried on to a considerable extent as for instance two longitudinal sections may be
made dividing the whole baking surface into nine sections and so on.
In the second place I remove these objections by constructing the drawplate (or
baking plate proper) so as to cover or constitute about one half of a system of
endless chains which pass over pulleys or chain wheels or drums attached to both
ends of a frame which takes the place of the old solid drawplate.
In the ordinary drawplate or travelling baking plate ovens, the plates themselves
are mounted on wheels on which they run in and out of the baking chamber. My
improved drawplate takes the shape of a web or endless belt and chains which pass
over polygonal or cylindrical drums or chain wheels of horizontal axis of revolution;
these wheels or drums are mounted to the ends of the frame waggon or carriage
on the top of which the web like baking plate rests. By means of a handle put
on the axle of the drum or chain wheels in front, the baking web may be moved
to occupy any desired position relative to the frame round which it revolves.
This compound waggon or baking plate need not be drawn out of the baking
chamber any further than is required to expose sufficient baking surface for placing
two or three rows of loaves on; because by turning the handle and revolving the

page_text: web on the frame, fresh surfaces are exposed and can be filled with succeeding rows
of dough loaves, the rows previously put on having travelled into the oven chamber.
When the entire plate is filled the waggon is pushed right into the chamber and the
door is closed for baking the whole batch.
The baking web is moved like an endless belt, part of which being covered by
strips of iron or other suitable material, when occupying the top of the frame, forms
the regular baking plate.
By revolving the axle of the drum in the opposite direction that part which forms
the baking plate travels out of the oven to allow the loaves to be removed row by
row. When all the bread is drawn almost the entire baking plate appears under-
neath the frame and a further batch of bread is now set the chain wheels being
turned in the reverse direction and the dough loaves being put row by row on that
part which next travels into the oven. When the last rows of dough loaves are set
on the plate, the whole frame is pushed into the oven again; the space through
which the entire frame travels being only that corresponding to the width of a few
rows of loaves instead of the entire batch.
The oven is now shut up again and the bread is baked as before.
.
improvements in Drawplate Continuous Baking Ovens.
A. communication from Messrs. WERNER & PFLEIDERER, in Cannstatt,
Germany, Engineers.
I, PAUL PFLEIDERER, 86 Upper Ground Street, Blackfriars Road, London S.E.,
Engineer, 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:-
Some of the usual objections made by many bakers to the introduction of
drawplate" or travelling baking plate ovens as hitherto constructed and in which
the total length of baking plate draws out into the bakehouse are those of want of
room, of the goods suffering by having to rest on a hot bottom without corre-
sponding top heat for some time previous to being run into the oven and of being
difficult to handle when built in decks or storeys one above the other. These
objections are entirely met by this invention according to which the total baking
surface is either sub-divided into a number of sectional drawplates which can be
quickly filled or emptied one after the other or it is constructed as an endless web
mounted on a carriage on which it can be revolved or reeled in and out of the oven
in endless conveyor-belt-fashion requiring rails in the oven only, it being sufficient
to draw it out only as far as to expose enough baking surface for two or three rows
of loaves or by a combination of the two principles the former of which is illustrated
on Sheet 1 the latter on Sheet 2 of accompanying drawings Fig. 1. Fig. 5 and
Fig. 6 are elevations Figs. 2, 3 and 7 are plans of drawplates A, B, a, b and Z as
they appear in the baking chamber which is shown in section with only one oven
mouth and which may have two but is shown at one end.
Figs. 4 and 8 are perspective views showing some of the plates drawn, are rails
on which the drawplates travels are strips or laths of which the endless web-baking-
surface is composed and t are chains which are employed to make up the continuity
of the endless web from where the laths s commence to where they cease or the
strips or laths s go all round making by themselves one continuous baking surface.
w are reels drums or pulleys with their axles mounted in bearings fixed on the
wagon drawplate Z; h is a handle or wheel by which we can be revolved thereby
winding or reeling the web baking surface into and out of the oven.

page_text: In Fig. 1 and Fig. 2 dotted lines show the sectional drawplates a and b as they
appear when drawn out of the baking chamber being telescoped over a which
position is also shown very clearly in Fig. 4 while Fig. 5 shows the web drawplate
projecting from the baking chamber as if it were just got ready for setting or as if
the batch had just commenced to be "drawn" a few rows of loaves only having
been removed.
By further winding or reeling the web out row after row of the baked loaves are
taken off or allowed to drop on a receiver in front of the oven and when all out
the motion is reversed and row after row of dough loaves are put on, when full the
entire carriage or drawplate is pushed into the oven which is closed and the bread
baked as in ordinary drawplate ovens.
Instead of six Figs. 2 and 4 or two Fig. 3, nine or four or any other divisible
number of sections or divisions may be used and instead of running B or b over the
top of A or a this may be reversed if sufficient vertical distance is left to run B
or 6 under A or a with loaves on the top of B or and instead of baking at such
different levels between a and b these levels may be brought to one and the same
level by lowering the higher or raising the lower drawplate or by adjusting both
when they are in the oven by any known mechanical means as for instance mounting
the rails in weighing machine balance fashion and either of these arrangements
will work without any other change in the principal structure of the oven as
furnace or oven mouth but the door for closing the oven mouth hermetically as in
our ordinary Wieghorst ovens may also be constructed in corresponding independent
sections.
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
a) In "Wieghorst " ovens i.e. in steampipe ovens with drawplates and separate
furnace bars.
b) In other steam or hot water pipe ("Perkins") or in gas heated baking
ovens.
c) In otherwise heated so called "flue" or "patent" baking ovens the
arrangement.
1) Of a number of sectional drawplates travelling (or telescoping) one over the
other in place of one single drawplate running the whole length of the entire
baking surface out into the bakehouse.
2) Of a drawplate the baking surface of which is formed of a series of strips or
links into an endless band working over drums or reels for reeling or winding
the whole of the goods gradually but quickly into and out of the oven and
3) Of a combination of these two devices which is of special value with ovens of
several decks or storeys.
1551
1901