Note: Descriptions are shown in the official language in which they were submitted.
BACKGRO~ND OF T~IE: INVEN*ION
This invention relates t.o a baker's oven.
A commonly used type of baker's oven is Or
travelling oi.'l or gas ei red type, having an endless conveyor
for support racks on which tins for breaci or other bakery
products are carried, the baking process beinK completed
between the loading oi' the products, and their unloading
after completion O-e a circui.t within the oven. An oven oi'
this type is large and expensive to manufacture, and it has
the disadvantages that the vibration of the conveying system,
and also the use of :eans to promote even heat distributi.on
within the oven, has adverse ef-eects on certain bakery
products. Moreover, such an oven is not, of collrse, suited
to the simultaneous baking Oe products which have dief'erent
baking requirements. Dev:ices eo:r ].idding bread tins for the
baking of sandwich 10aVeS have been complicated and expensive
in such ovens.
The general. object of -the present invention is to
provide a baker's oven in which a variety of kinds of
products with diF-eerent baking requirements may be very
satis~actori1y baked sirnu]taneously. Other ob,jects achiev-
able in pref'erred embodiments o~' the invention are to provide
such an oven which incorporates very simple a.nd e-eeective
liddin~ means for bread tins, is Oe particula.rly compact,
simpl.e and econom:ical construc-tion, which has low (~perating
.~b
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and maintenance costs, and which is very easy and convenient
to load and unload.
In accordance with the broad concept of one aspect
of the invention, there is provided and claimed herein a
baker's oven comprising: a casing div:ided into a plurali-ty of
superimposed compartments, a loading door leading into each of
the compartments; a substantially horizontal support for
articles to be baked in each compartment rotatable about a
subs-tantially vertical axis; heating means in each compar-tment;
and means for simultaneously ro-tating the supports, the
improvement comprising substantially horizontal heat insulating
decks separa-ting the compartments and a substantially
cylindrical heat insulating core in each compartment disposed
coaxially about the vertical axis and extending upwardly from
the support to a position close -to the -top of the compartment.
In a preferred embodiment, the interior of -the casing
is of subs-tantially vertical cylindrical form, a substantially
vertical shaft passing substantially coaxially through the
compartments, and the supports are mounted on the shaf-t -to
rotate simultaneously with the shaft.
Preferably, the heat insulating decks are peri-
pherally connected to the casing and are centrally closely
engaged about the shaft, and said core is disposed coaxially
about the shaft and rotating with the support.
Other features and objects o the invention will
be gathered from the following description of a preferred
embodimen-t having reEerence to the accompanying drawings,
wherein:
Fig. 1 is a perspective view of a baker's oven
83L~
according to the invention,
FIG. 2 is a cross-sectional view of the oven along
line 2-2 in FIG. 2,
FIG. 3 is a sectional vi.ew ol the botto~ part
o~ the oven along line 3-3 in FIG. 2,
FIG. 4 is a sicle view o:~ the oven with an access
door opened, and
FIG. 5 is a s.ectional view along line 5-5 in
FIG. 4.
DETAILED DESCRIPTION OF l'HE PRE~ERRED EMBODIMENT
.
The oven illustrated includes a casing 10 with a
substantially cylindrical :inner wall 11, an outer wall 12,
and interposed insulating material 13, the top 14 and bottom
15 of -the casing also being Or insul.ated double-wall
construct~on, as al?~o are horizontal decks lfi mounted within
-the casing and dividtng it i.n-to superimposed similar cc~mpart-
ments 17.
The outer wall 12 has a ~lat -~ront through which
doorways lead individually into the compar-tments 17, each .
doorway being provided with a door 18 wi1;h a transparent
~ t s~n
window 19. Individual control panelsJ~3 are provided for
-the oven compartments 17.
A main drive sha.ft 21 passes axially -througtl -the
oven top 14, declcs 16 and bo-ttom 15, and is rotatable by
any suitable power uni-t in a bearing 22a in the oven -top and
.,
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-in a thrust bearing 22b in the oven l)ottom In each
compartment 17 a support -tray assembly 23 is fixed on the
drive shaft, each assembly including a central. cylindrical
core 24 of shee-t metal internally reinforced and packed
with heat insula-ting ma-te~ial, a series of arrns 25 radiating
:Erom the core bottom to a rim 26 supporting an annular
mesh -tray 27. Each oven compartment 17 is individually
heated by thermostatically controlled lower heating elements
28 and upper heating elements 29, each being doubled and
shaped to spiral section form.
Any one or more of the oven compartments 17 may
be provided with lidding means according to the invention,
the oven illustrated being p:rovided with such means in each
Or its four compartments. In each compar-tment an annular
lid 30 is ~itted about the core 2~, being made ne a nurnber
of siml:lar flanged sectors bolted -together. To facilitate
the raising and lowering of the lid in parallelism, a number
of rollers 31 are mounted under -the inside periphery of the
annular lid, When the lid is lowered, these rollers engage
a sleeve 32 about the lower part of the core 24, and when the
lid is raised there is some clearance between the rollers and
the core. The outside periphery of the lid closely approaches
the inner wall 11 o e -the oven.
Each of the lids 30 of -the oven may be individually
raised and lowered by a lidding lever 33, the four levers
,(.
being mounted in pairs, one pair a-t each side of the oven.
In each pair, one lever is secured to an end of a shaft 34
rotatable in bearings 35 on the oven casing top 14, and the
other lever Oe the pair is fixed, by an I,-shaped bracket 36,
to a tubular sleeve 37 rotatable on the sbaf-t 34 between
its bearings 35, -the two lidding levers 33 being arranged
so that each may be moved withont fouling -the other.
At opposite si.des of the oven, upwardly extending
lever arms 38 fixed to the shaft 34 are pivotally connected
to the upper ends o~ corresponding connecting rods 39. Also,
at opposite sides of the oven, the bracket 36, and a lever
arm 40 which is a:lso secured to the tubular sleeve 37, are
pivotally connected -to the upper ends O e corresponding
connecting rods 41. All o~ the connecting rods are ad~ustable
by ~eans o.f turnbuckles 42.
At opposite sides of the oven, corresponding
connecting rods 39 and 42 are connec-ted to the middle parts
o~ a pair of horizon-tal li~ting arms 43 which are shaped to
conform to the curvature o~ the oven wall; each li~ting arm
being centrally fixed to a sleeve 44 slidable on a vertical
rod 45. From the ends o~ each li~ting arm 43, two li~ting
~ingers 46 pass through ver-tical slot-like open.ings in the
oven wall and, within -the oven compartment 17, are back-swept
or angled towards the direction of rota-tion o:t the s~lpport
tray assemblies.
In use, the hea-ting elements 28 and 29 are operated
to bring each of the oven compartments -to its predetermined
thermostatically control:led temperature, and the main drive
shaf-t 21 is driven to cause -the support tray assemblies 23
to be rotated at a predeter-mined speed. Each o~ the
compartments 17 may be loaded with conventional baking -tins
for loaves, cakes or other bakery products and/or with sheet
metal trays on which articles to be baked are placed. The
dimensions of the core 24 and of the mesh tray 27 are such
that a considerable number of rectangular bread baking tins
~not shown) may be supported radially on the tray, their
inner ends near to the core, their outer ends near to the
rim 26. The tins, then, wlll be well spaced apart except
at their inner ends, and therefore there w:ill be good circul-
ation o~ heated air between the tins and even baking of theircontents, Moreover, the removal of the tins at the conclu~ion
: of baking will be ~acilitated by this spacing, and no tins
need to be loaded in front of others.
When it is required that the bread tins o~ any oven
compartment should be lidded for the production of sandwich
loaves, the appropriate lidding lever 33 is swung down so that
its two connecting rods 39 and 41 descend and with them the two
li.f-ting arms 43 and the lid 30, previously held stationary
with:in the upper part o~ the compartment. When the lid is
2~ lowered onto the baking tins, its rollers 31 are brought down
onto the sleeve 32 abou~ t.h(' cole 24, so the licl is caused
to -turn with the rotating core. To raise the l:id 30, the
appropriate lidding lever 33 is swung up, -to bring the
lever arms 38, or the bracket 36 ancl lever arm 40, beyoncl
"dead centre" posi.tions, so the lid 30 is l.i:fted to, ancl
retained in, raised pos-ition.
It will be found t;hat t.lle spiral arrangemen-t Or
the heating elements ensures even heatin~ of the produc-ts
being baked and, most o~ the unused space o:f each oven
compartment being occupied by tne i.nslll.ated core 2~, li-ttle
pre-heating oi any compartment will be requi.red before
commencing baking. The oven, althou~h very economical of
space, may be used to bake a varie-ty Or products a-t the same
time, at different temperat:ures i~ required.
An oven according -to the invention may have two or
three compartments instead Or t:he four ill.ustrated, and may
: be readily enlarged by superimposing it on a supplementary
one-compartment or two-compartmen-t unit. For this purpose,
-the main drive shaft 21 may includl? a bottom end-piece 46
rotatable in the thrust bea.ring 22b and rernovably engaged in
the tubular main part of the drive shaft, a pln and slot
device ihdicated at 47 prevent.ing relative rotati.on of the
two parts. To a.dd an e~tra compa.r-tment at the bottom ol! the
oven, it is then necessary only to remove the thrust bearing
22b and replace i.t on -t.he bottom of the .supplemellta2y unit,
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and to lengthen the d:rive slla:it by interpos-ing an appropria-te
leng-thening piece between the main part o:~ the drive shaft
and its end-piece 46.
