Improvements in Bakers or Confectioners ovens.
Year: 1899

page_text: Improvements in Bakers or Confectioners ovens.
I, CHARLES HAWKINS, of Post Office, Barnard's Green, Malvern, in the County
of Worcester, Baker, do hereby declare the nature of this invention to be as
follows:-
This invention relates to bakers' and confectioners' ovens which are heated by
a system of hot water pipes laid within their bottoms and crowns, and which are
arranged to be acted upon by the combustion products from the fire or from a
fire flue, and has for its object certain improvements by which the heat of an oven,
or of ovens, can be better regulated and controlled than hitherto.
According to this invention the system of hot water pipes (non-circulating)
extend longitudinally both top and bottom of the oven for the greater part of its
surface, and are arranged parallel as ordinarily, but their one or back ends, which
extend through the back wall of the oven into the fire flue, are gathered in closely
or packed so as to converge either to the centre in a cluster, so as to leave upwardly-
directed passages each side of them, or are collected to one side so as leave an
upwardly-directed flue clear of them in the other corner of the fire chamber, or
half of them are gathered in or packed at the one end and half at the other so as
to form an upwardly directed flue in the centre of the fire chamber between them,
and dampers are fitted through the fire flue's walls which are adapted to be pushed
in or drawn out so as to either cover up the gathered in end of the tubes and pro-
tect them from the heated gases and products from the fire, or expose them to the
fire as may be desired, and also to shut off or open communication between the
fire flue and the next tier of ovens or the chimney through the upwardly-directed
passages as aforesaid. These upwardly-directed passages or flues are in the case of
a three or four tier or deck oven the means of communication between the one set
of water tubes and the other. The products from the fire may either pass to to the
tubes of the second and third ovens through the first system of tubes or through
the vertically directed passages, as may be desired, by the arrangement of the
dampers. As an example, if the ends of the hot water tubes in a three tier or deck
oven are centrally gathered in and packed in the fire chamber and passages left
each side of them, a damper can close over and cover the tubes of the first oven
from the fire and the passages each side of them can be left open for the passage
of the heat and gases to the gathered in tube ends of the second oven or to those
of the third oven direct, or the said heat and gases may pass upwardly between the
tube ends of the first oven (the passages each side being closed by the dampers)
to the tubes of the second oven, and so on, which will allow of any one of the three
ovens being cooled off and the others being kept hot, or all of them being heated
to the full.
The dampers fit over the tubes like a case, and are preferably independent of
each other, and those which close the upwardly directed passages can be either
coupled or independent, but these last named need not be of the same construc-
tion as those which cover the ends of the tubes. Dampers made of refractory

page_text: material or sand dampers may be used, especially having regard to the ones which
cover the tubes, as they are of a box section and are preferably made to slide, in
view of being operated from the back of the oven.
In cases where the fire is fed with fuel from the side of the oven, the dampers
may be made to hinge up and down into and out of position. The chimney at the
top of the block of ovens is in most cases central, in view of the even passage of
the heat through the system, but where the ends of the tubes are collected or
gathered in close to one side only, the position of the chimney would be on the
side.
The water tubes in this system of heating ovens are, in the ordinary way,
hermetically sealed, and each is independent, and above and below each oven they
are arranged in parallel rows some distance apart, but according to this invention
where they project into the fire chamber they are gathered close together so as
to form flues each side them, or between them, for the passage of the products
from the fire if desired.
The ends of the hot water tubes which project into the fire chamber may be of
an elliptical or elongated cross section, in order to more closely pack the said ends.
D
W. P. THOMPSON & Co.,
11, Burlington Chambers, New Street, Birmingham.
Patent Agents for the Applicant.
I, CHARLES HAWKINS, of Post Office, Barnard's Green, Malvern, in the County
of Worcester, Baker, do hereby declare the nature of this invention 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 bakers' and confectioners' ovens of the type heated by
a series or system of independent hermetically sealed water-containing pipes in
which steam is generated, and which are laid or arranged within the bottoms and
crowns of the said ovens so that one of their ends project into a combustion chamber
or a fire flue to be acted upon by the fire or other heat products; such types of
ovens being generally known in the trade as steam ovens.
This invention consists of certain improvements in the construction of the
combustion or fire flue and passages for the products, the provision within the said
flue and passages of dampers or shutters controlling the said passages and cover-
ing the ends of tubes, and an arrangement of the ends of the hermetically sealed
tubes within the combustion or fire flue, the said improvements having for their
object, firstly, the better regulation and control of the heat of the oven or ovens
than hitherto and, secondly, a reduction in the amount of fuel required for pro-
perly heating the tubes. The invention is applicable to either one, two, three,
or more deck ovens, but is of particular importance in ovens of more than one
deck.
In the accompanying sheets of drawings a three deck oven provided with improve-
ments according to this invention is shown in one form in Figs. 1 and 2, the repre-
sentations being respectively a horizontal and a vertical section through the
important parts of the structure. In these figs. the water pipes c, each hermetic-
ally sealed at their ends, extend longitudinally both top and bottom of each oven a²,
in the block a, for the greater part of its surface, and are arranged therein under
the beds or floors at in parallel systems as shown, but their one and back ends c

page_text: as they pass or extend through the back wall a³ of each oven into the vertical com-
bustion or fire flue d, are gathered in or closely packed towards the centre of the
system, so that the fire flue d is much less in dimensions in a cross direction than
the breadth of the ovens c, although, as will be hereinafter described, the gather-
ing in of the tube ends in the fire chamber need not be in every class of oven.
The fire flue d is a vertical passage running straight up from the fire bars ² and
terminating in an outlet at the top of the structure, and is of sufficient breadth
in the longitudinal direction of the ovens to cause the tube ends c² to project only
half the distance across the fire flue,, the other portion of the said flue acting as
a by-passage for the heat products when the ends of any of the series of tubes
are protected by dampers 9, of a breadth half the size of the fire flue, and which are
fitted horizontally in the extreme back wall of the structure so as to work back
and forth across the fire flue d. These dampers form an important feature of this
invention and are part of the means by which the heat of the whole or any one
or more of the ovens in the block can be regulated. One of such dampers is
shown in face view in Fig. 1 as covering the by-passage before mentioned in the
fire flue around one of the series of tubes, so that the products from the fire must
pass over the tube ends and play on them, and it will be obvious from Figs. 1
and 2 that the products from the fire must pass upwardly between and over the
whole of the ends of the four series of tubes when the dampers g are in the
positions shown, viz., cutting off the by-passages at the back of the said tube ends.
When it is desired to lessen the heat of any of the ovens of the block the particular
damper or dampers opposite the particular tube ends are pushed inwardly, by their
handles g³, to cover the ends of the tubes and protect them from the fire products,
at the same time opening the by-passage at that particular point to enable the
products to pass freely at the back of the covered tubes. It will be clear from
this that any one of the ovens can be shut off without interfering with the heating
of the others, and this to almost any required degree. The dampers as shown are
simple plates sliding in the brickwork of the structure underneath the tube ends,
but they may be sand dampers of a U-section if desired, so as to cover the said
tube ends under and over.
In the arrangement of ovens according to this invention as shown in Fig. 3 the
ends of the tubes are gathered in and project right across the fire flue d, but
the said flue is of the same breadth as the oven so as to leave by-passages at
its ends, through which the products pass when the ends of the tubes are pro-
tected. In this arrangement three independent dampers g, g², g³, are fitted to each
series of tubes; the position in the drawing showing the by-passages & closed
and the direct passage around the tube ends open.
A similar arrangement as Fig. 3 is shown in Fig. 4 other than half the tubes are
gathered or packed into one end of the fire flue and half into the other end of the
fire flue, leaving the by-passage for the products in the centre.
In this arrange-
ment three dampers g, g, g³, are used.
A further modification of the invention as shown in Figs. 1 to 4 is shown in
Fig. 5. In this oven the ends of the tubes are gathered in or closely packed in
one end of the fire flue d, and the by-passage is left at the other end; two
dampers g, g, being necessary.
The important difference between the arrangement in Figs. 1 and 2 and those
of Figs. 3, 4, and 5, is that, in one case, the breadth of the damper is half that
of the fire flue and the tube ends extend only half way, and, in the other case,
the dampers are the full breadth of the fire flue and the tube ends extend right
across.
A still further form of oven according to this invention is shown in Fig. 6.
In this arrangement the by-passages d³ are formed at the ends of the fire flue
independent of the said flue, and the ends of the tubes are not gathered in, but
extend right across the said fire flue. The by-passages are fitted with
dampers g², g, for each series of tubes, as also is the fire flue, and the said passages
communicate with the fire flue through holes or openings in the side wall just

page_text: .
underneath each series of tubes; the said passages being common to each set of
tubes.
In cases where the fire in the fire flue is fed from the side of the oven the
dampers could and, preferably, would, be made to hinge up and down into and out
of position. The outlet d³ of the flue d is in most cases central in the block of
ovens, in view of the even passage of the heat through the system, but in cases
where the ends of the tubes are gathered in to the one side, as in Fig. 5, the
outlet would preferably be on the side.
The projecting ends of the tubes may be of an elliptical or elongated cross
section, in order to more closely pack them when gathered in.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I-claim is:-
First. In ovens of the type herein described and set forth, forming the com-
bustion or fire flue whereinto the ends of the tubes project with by-passages
independent thereof, or forming part therewith, and fitting to the said Blue and
passages one or more dampers which cover up the tube ends and passages and
open or expose them for the purposes substantially as described.
Second. In ovens of the type herein described and set forth, gathering. in or
packing the ends of the tubes in the combustion or fire flue, forming the said
Hue wherein the said tubes project with by-passages independent thereof or form-
ing part therewith, and fitting to the said flues and passages dampers which open
and close the passages and cover up or expose the tube ends, for the purposes sub-
stantially as described.
Third. In ovens of the type herein described and set forth the method of form-
ing a by-passage in the combustion or fire flue whereinto the ends of the tubes
project and of opening and closing the said passages and covering up the tube
ends, substantially as described and set forth in Figs. 1 and 2.
Fourth. In ovens of the type set forth forming by-passages from the com-
bustion or fire flue into which the ends of the tubes project and opening and
closing them and protecting and exposing the said tube ends against and to the
products in the manner substantially as described and set forth in Fig. 6.
Fifth. In ovens of the type herein set forth the arrangement of the tube ends
within the combustion or fire flue and the method of forming the by-passages and
opening and closing them and covering and exposing the tube ends as set forth
in Figs. 3, 4, and 5.
T
17th day of May 1899.
W. P. THOMPSON & Co.,
11, Burlington Chambers, New Street, Birmingham,
Also of Liverpool, London, and Manchester.
Patent Agents for the Applicant.