Note: Descriptions are shown in the official language in which they were submitted.
- ~o~
The present invention relates to shutter means for
closing or obstructing the window which is normally found in
tne oven doors of domestic cooXing appliances.
For many years, the cook stove manufacturing industry
h~s provided its oven doors with windows through which the
housewife may observe t~e cooXing process which is being
carried on within the oven without the necessity of opening
~he oven door as was previously required.
More recently~ the cook stove manufacturing industry ~ -~
has developed various forms of an oven which may be heated to ~;
a ~elatively high temperature or the purpose of cleaning food
soil from the interior oven walls by pyrolysis. The tempera-
tures which are involved in the pyrolitic cleaning action
are substantially higher than those which are encountered in
normal cooking operations. ~ormal cooking temperatures do ;~
not, as a rule, exceed 500F to S50F w~ereas the pyrolitic
cleaning action takes place somewhere between 800F and
aoooF. l :
Initially, it was believed that it would be necessary
to sacrifice the presence of a window in the oven door in
1~ order to achieve the obvious advantages o~ the "self-cleaning"
i~ ~eature and the attendant high temperatures. The reason for
this is that the conventional double-pane window design of
the prior art is not capable of confining the increased
amount of heat energy to the oven cavity and, accordingly,
the heat los~ through the window was excessive and radiation
through the window presented a hazard to the housewie.
. , ~
- 2 - ~
i, - . ~
02~
The presen~ invention, however, makes it possible to
retain the advantages of a window in the oven door while, at
the same time, providing simple and automatic means whereby,
during the high temperature self-cleaning cycle, the window
may be obstructed so as to retain the high temperature within
the oven and to prevent both exces.sive heat loss and radiation
through the window. -
According to the present invention, in one embodiment,
an oven door window is provided with a peripheral frame within
which are mounted a plurality of spaced, parallel~ substan-
tially flat blades, rotatable about their longitudinal axes
from a first position in which the flat blades are parallel
to one another and normal to the plane containing the window
,.j , ~
I so that the interior of the oven may be viewed between the
blades, to a second position wherein the blades are rotated
~ through substantially 90 so as to lie in substantially a
"'' ;:~
single plane parallel to the plane of the window whereby the
window is completely obstructed and closed by the blades,
, ~ . .
operating means being provided to simultaneously move all of
the blades as a result of a door locking function which is a
preced~nt to the initiation to the self-cleaning cycle.
A preferred embodiment of the invention will now be
disclosed in detail with reference to the accompanying
; drawings in which like parts are denoted by like reference
numerals in the various views and in which:
Figure 1 is a perspective view, partly cut away and
exploded in order to sho~ an oven door embodying a shuttered
, ~ ,
,: - 3 ~
,
, ^ .. . . . . .. .
window constructed and arranged in accoxdance wi~h the present
invention;
Figure 2 is a section view taken along line 2-2 of an
assembled door as illustrated in Figure l;
Figure 3 is a fragmentary detailed view of a portion o~
; the shutter actuating mechanism illustrated in Figure l;
~ igure 4 is a fragmentary detailed view showing the
components o~ Figure 3 assembled and in a different position
and
Figure 5 is a fragmentary view showing a portion of the
shutter actuating element.
Turning now to Figures 1 and 2, an oven door embodying
the shuttered window of the present invention is illustrated.
In Figure 1, the door may be seen to comprise an inner shell
10 having flanged edges which will engage with an outer shell
11. Convenien~ly, the outer shell 11 is provided with flanged
edges, the lower such edge being provided with tabs 12 which
may be inserted in slots 13 in the corresponding edge of the
~:
, ~, . .
inner shell 10 to secure the two shells together along the
lower edge. The upper edges may then be secured together by
means of screws such as 14 received in corner brackets 15
carried by the upper corners o~ the outer shell 11 o~ the
door. `
As seen in Figure 2, the inner shell 19 is also pro-
vided with a rearwardly extending sheet metal plug or box-
like portion 16 w~ich is of a size such that it will fit
relatively snugly within the opaning to the oven. The oven ~ ; `
, '
1~)7~
opening is indicated in dotted lines in Figure 2 by the oven
upper wall 17 and the oven bottom wall 18.
The plug or box-like member 16 is secured to the rear-
ward face o~ the inner shell 10 by brackets 16a and is pro-
; viaed with a heat resistant, compressible se~l member 19 so
that the oven door, when in its closed position, will tightly
close the oven opening with the box-like section 16 extending
slightly into the oven cavity.
The rear ~ace of the plug 16 i5 provided with an
aperture defined by a peripheral flange 20~ the flange 20
receiving a sheet of heat resistant glass 21 such as that
sold under the trade mark "PYREX".
The outer shell 11 o~ the door is also provided with
an opening defined by an inwardly extending peripheral flange
22, this ~lange engaging the rim 23 o~ a frame 24 which mounts
a pair of spaced, parallel panes of glass in a self-contained
unit which is of conventional construction.
~, . . .
The plug or box~like section, interiorly of the glass
pane 21 presents a recess aligned with the three panes of
glass constitutiny the window in the door within which the
shutter mechanism is mounted.
In Figure 1, the shutter mechanism will be seen to
comprise a channel-section frame 25 which defines a rectangu-
lar opening substantial~ly co-extensive with the size of the
panes of glass constituting the window. The ~rame 25 com-
prises side members 26 and 27 and a bottom me~ber 28 and a
top member 29. The frame-is secured in,position by means of -
brackets 30 which may be spot welded to tha inner surface of
the plug or box-like member 16. Angular brackets 31 are then
secured to the brackets 30 by means of screws so that one
free end may bear upon one flange of the channel-section : ~
frame member and retain it in position. As seen in Figure 2, . .-
.. the frame members (only 28 and 29 o~ which are shown) serve ~:
also to retain the pane of glass 21 within the flange 20.
Bottom and top frame members 28 and 29 are provided with
.~ a plurality of spaced and aligned apertures 32 and 45 by means
10 of which the spaced, parallel, substantially flat blades 33 .
may be mounted as shown in Figure 1. The blades are capable .
of rotating through 90 from a irst position as sh~wn in
Figure 1, in which they are parallel to one another and normal
.~ to the panes of glass so that a housewife may see through the . :
window to a position in which the flat blades 33 are substan~
: tially co-planar and parallel to the panes of glass as shown,
in a fragmentary view, in Figure 3. ~.
Turning now to Figures 3 and 4, each of the blades is
formed from a length of extrusion, conveniently of aluminum,
defined by a central rib portion 34 from which extends, on
both sides, the blade portion 35 and 36. One of the blade
portions 36 is provided with an off-set segment 37 along its
edge 50 that, as seen in Figure 3, the end of blade portion
35 may lie within the off-set portion 3~ of an adjacent -
blade, thereby enabling the blade portions of adjacent blades
to be co-planar when they are in the position shown in
Figure 3.
, ~ :
.-; - 6 -
-- : :. :
' ; '~,
- , , , ~ -
.: .
~o~o~
At the lower end o~ the blades (not shown in detail),
each blade is provided with a pin inserted in a central bore
38 in the central rib 34 and such pin is then inserted through
the aperture 32 in the bottom frame member ~8. A pin 39 of
the kind just described may be seen in Figure 2.
Each o~ the blades 33 is provided, at its upper end,
with a cranked pin 40 having a lower portion 41 adapted to be
inserted in the bore 38. Small tabs 4~ may be struck from
the material of the pin 40 and these tabs may be received in -`
. ~ .
slots 43 in the bore 38 so as to ~ix the cranked pin 40 rela-
tive to the blade 33 to resist rotation relative thereto.
The upper portion of the cranked pin 40 is of~-set as at 44.
: The blades 33 are pivotally mounted in the upper ~rame
.
member 29 by passing through apertures 45 provided tharein
. aligned with apertures 32 in bottom frame member 28.
. The of~-set portions 44 of the cran~e~ pin 40 are then
: ~ ,
~ .received in a plurality of apertures 46 in a slidable plate 47
.. ~ lying above frame membPr 29 and linking the o~-set portions
44 of all o~ the cranked pins 40 associated with each of the
.. ,~ . ~
blades 33.
. ~: . , .
. From the construction so far described, it will be
.,. ~ .
apparenk that the sliding plate 47 may be reciprocated to
move the blades, in unison, ~rom the position shown in Figure
. 3 to the position shown in Figure 4 and vice-versa.
The movement of the sliding plate 47 is achieved by a
mechanism disclosed in Figure 1.
' First, the sliding plate 47 is supported in slotted
.. ,' -
. ....................... .
.' - 7
~',
-. . . ~ . .
~,
o~
tab~ ~ carried by the upper frame me~ber 29 and, cen-trally
of i~s length, is provided with an operating arm or extension
49. ~:
Secured to the inner door shell 10 is a mounting bracket
: 50 upon which is pivotally carried a downwardly extending
lever 51 to which is welded~ at 52, a spring steel element 53
which extends upw~rdly to position a hori70ntally disposed
portion 54~ immediately inside and below an elongated horizon-
~al slot 55 formed in the inner door shell 10
The oven construction with which the door is associated
is provided with a door locking element comprising a rod 56
having a formation of a hooked end 57 which projects through
the portion 58 of the stove construction and which is posi- .
tioned so that it will enter the elongated horizontal slot 55
~ , . ..
~ when the door is in the closed position. As long as the hooked
':~ portion 57 is in the horizontal position shown in Figure 1,
the door may be freely opened and closed without interference. ~ ~
~ However, when the high temperature, self-cleaning, ~:
:~ . pyrolitic cycle is initiated, the shaft 56 is rotated through .
- i .
substantially 90 in the direction of the arrow 59 with the.
door in the closed pOS.Ltion. The hooked portion 57, during
this rotation, will encounter the horizontal portion 54 Q~ t~e .;
element 53 which will be pressed downwardly, thereby causing ~ :
:
~ the lever 51 to pivot to the right about pin 60 as seen in
.: Figure 1.
Turning now to~Figure 5, lever 51 may be seen to be
provided with a forwardly projecting tab 61 at ~its l~wer end, ~`~
.'. ~ . - ' ~
: - 8 - :
:
'02(~
provid~d ~ith an ap~rture 62 within whieh is rec~i~ed the
hooked end 63 of a stif~ wire 64. The stif wire 64 engages :
,
operating arm 49 of the sliding plate 47. The arm 49 is
.~ provided with an upwardly bent portion 65 at its ~ree end and
t~is portion 65 is slotted at 66, the slot passing entirely
through the element 65 and a short distance into the horizon-
tal extent of the arm 49. The stiff wire 64 is provided wi-th
a suitably located croo~ at 67 which engages the slot 66 and,
thereby, is firmly secured to the arm 49. The end 68 of the
.10 wire 64 is either formed into or secured to a tension spring :
69, the :Eree end of which is mounted to a bracket 70 carried
.. by the inner door shell 10.
,............. The spring 69 will constantly urge the arm 49 and,
s
r`:"' therefore, the sliding plate 47 to the left, as seen in
Figure 1 and will urge, therefore, the shutters or blades 33 ~:
to the "open" position as shown in Figure 1. This position
is determined by a stop constituted by a tab 71 struck up
from the material of the sliding plate 47 which engages the
- :;
. ~ slotted bracket 48 within which the sliding plate 47 is
."i
~ 20 received.
.
When the door is closed and sha~t 56 is rotated
.: through substantially 90 to lock the door, the hooked end
57 of the door locking element will, in addition to engaging
, ,1 . ~ .
the interior sur~ace o~ the inner door shell 10 to thereby
lock it in the closed position, also depress the horizontaI
element 54, swing the lever 51 to the right as seen in Figure ~
. .; ~j 1, slide the sliding plate 47 to the right as seen in Figure
-,; .
: . 9 : ~.
: ~ :
- . , . ~ .
. . . - . :
" ` ~LO~OZ~
1 and move the blades 33 from the position shown in Figure 4
to the position shown in Figure 3, thereby effeckively
shuttering the oven door window in a manner whi~h will make it
possible for the windowed door to re~ain the high temperatures
within the oven for the self-cleaning cycle and to reduce the
heat loss and radiation through the window to an acceptable ~:
level.
~.
, .
.' . ' ' ' ' ` ` ': ~'
'' ' ' ', ,,'' ~
.
-: . ,: :
, :
., ~ .
.j ~
. , .
,:' ,~ . '
: :.
. '
' ' ' ' ~;
,~ ~O
- .
.
, .. ,.. . - - -
