U.S. patent application number 11/747609 was filed with the patent office on 2008-11-13 for latch for oven door.
Invention is credited to Brock Francis, Kevin L. Griswold, Jiri Rabas.
Application Number | 20080276925 11/747609 |
Document ID | / |
Family ID | 39968404 |
Filed Date | 2008-11-13 |
United States Patent
Application |
20080276925 |
Kind Code |
A1 |
Griswold; Kevin L. ; et
al. |
November 13, 2008 |
LATCH FOR OVEN DOOR
Abstract
A latch for an oven door is provided. The latch includes a bar
defined within a frame of the oven and a door rotatably mounted to
the frame. A latch arm is pivotably mounted to the door and a
handle is pivotably mounted to the door by an operator. The latch
arm engages the bar in a first position of the handle with respect
to the door.
Inventors: |
Griswold; Kevin L.;
(Williston, VT) ; Rabas; Jiri; (Lynnwood, WA)
; Francis; Brock; (Hinesburg, VT) |
Correspondence
Address: |
BRINKS HOFER GILSON & LIONE
P.O. BOX 10395
CHICAGO
IL
60610
US
|
Family ID: |
39968404 |
Appl. No.: |
11/747609 |
Filed: |
May 11, 2007 |
Current U.S.
Class: |
126/19R ;
126/197 |
Current CPC
Class: |
F24C 15/022 20130101;
F24C 15/024 20130101 |
Class at
Publication: |
126/19.R ;
126/197 |
International
Class: |
F24C 15/00 20060101
F24C015/00; F24C 15/02 20060101 F24C015/02; F23M 7/00 20060101
F23M007/00 |
Claims
1. An oven, comprising: a cooking compartment partially defined by
a frame with an inlet opening, wherein a periphery of the cooking
compartment comprises a bar; a pivotable door engageable with the
frame to fully enclose the cooking compartment, comprising a
pivotable latch arm and a handle; a first pin pivotably connected
to the latch arm and the handle; and a second pin that extends
parallel to the first pin and through a slot in the latch arm;
wherein the latch arm and the handle are pivotably connected by the
first pin and the latch arm is pivotable by pivoting the handle
with respect to the door.
2. The oven of claim 1, wherein the connection between the slot and
the second pin defines a range of relative motion between the
handle and the latch arm.
3. The oven of claim 2, wherein the latch arm further comprises a
finger extending therefrom to provide pivotable contact with the
bar.
4. The oven of claim 1, wherein the first pin extends from an
operator fixed to the handle.
5. The oven of claim 1, further comprising a biasing member
arranged to bias the latch arm against the frame to prevent the
door from rotating with respect to the cooking compartment.
6. The oven of claim 3, wherein the finger comprises a chamfered
edge and a locking edge.
7. The oven of claim 6, wherein the locking edge contacts the bar
in a latching position.
8. The oven of claim 6, wherein the latch arm is mounted on the
door such that the chamfered edge contacts the bar as the door is
rotated from an open position to a latching position.
9. The oven of claim 8, wherein the latch arm is operative to pivot
when the chamfered edge contacts the bar and allow the interior
surface of the door to engage the frame of the oven.
10. The oven of claim 1, comprising a first latch arm pivotably
mounted proximate a top surface of the door and a second latch arm
pivotably mounted proximate a bottom surface of the door.
11. The oven of claim 10, wherein the handle is pivotable with
respect to the first and second latch arms.
12. The oven of claim 1, wherein the handle is operatively
connected to the first pin with one of a spline, a keyed
connection, or a weld.
13. The oven of claim 1, wherein the latch arm, the first and
second pins, and an operator connecting the first pin to the handle
comprises a modular assembly removeably attachable to the door with
a fastener.
14. A latch for an oven door, comprising: a bar defined within a
frame of the oven; a door rotatably mounted to the frame; a latch
arm pivotably mounted to the door; a handle pivotably mounted to
the door; and a pin constrained with the handle and extending
through the slot in the latch arm, wherein the latch arm is
configured to engage the bar in a first position of the handle and
to rotate free of the bar in a second position of the handle, and
wherein contact between the pin and the slot defines a range of
travel of the latch arm with respect to the handle.
15. The latch of claim 14, wherein the latch arm, the pin, and an
operator for connecting the pin to the handle comprises a modular
assembly configured to be attached to and removed from the door
with a fastener.
16. The latch of claim 14, further comprising a second latch arm
rotatable about the door, wherein rotation of the handle causes
similar rotation of the first and second latch arms.
17. The latch of claim 14, wherein the latch arm comprises a finger
with a chamfered edge and a locking edge, wherein the chamfered
edge contacts the bar as the door rotates from an open position to
a closed position, causing the latch arm to rotate and clear the
bar and allow the door to reach the closed position.
18. The latch of claim 17, wherein the locking edge contacts the
bar when the door reaches the closed position.
Description
BACKGROUND
[0001] Baking ovens are generally known in the art and provide an
enclosed volume for placement of a food product to be baked therein
and a heat source to bake the food product in the presence of
heated air. The enclosed volume of a baking oven normally includes
a frame with a plurality of walls that enclose a substantial
portion of the enclosed cooking volume. The frame is usually formed
from insulated materials that provide a relatively low thermal
conductivity, or a high resistance path for heat to leave the
enclosed volume of the oven to the atmosphere.
[0002] One or more doors are normally provided on an oven to allow
the enclosed volume to be selectively opened for placement or
removal of a food product within the enclosed volume. Doors are
typically closed as much as possible to limit the heat that escapes
the oven through the opening in the enclosed volume formed when the
doors are opened. Further, because the enclosed volume of the oven
is maintained at an elevated temperature to bake the food product,
an oven door that is susceptible to be spuriously or inadvertently
opened would provide a safety hazard for restaurant employees that
work in close proximity to a heated oven.
[0003] Because it is desired to reliably maintain the doors closed
(i.e. the internal surface of the door contacting the frame and
substantially sealing the enclosed volume of the oven), a number of
methods of maintaining the oven doors closed are known in the
art.
[0004] Other designs that hold oven doors closed are known in the
art such as complex locks or latches that provide mechanical
contact between the door and the frame. These complex mechanisms
are useful at retaining a door in a closing position with respect
to the oven frame, but are often undesirable because they often
include a complex opening and/or shutting procedure that reduces
the efficiency of a restaurant employee that must use the oven.
Accordingly, it is desired to provide an oven with an openable door
that can be reliably maintained in a closed position to enclose the
cooking volume, while including a convenient and simple opening and
closing mechanism.
BRIEF SUMMARY
[0005] A first representative embodiment of the disclosure provides
a latch mechanism for an oven door. The latch mechanism includes a
bar defined within a frame of the oven, a door rotatably mounted to
the frame, and a latch arm pivotably mounted to the door. A handle
is pivotably mounted to the door a pin is constrained with the
handle and extends through the slot in the latch arm. The latch arm
engages the bar in a first position of the handle and the latch arm
rotates free of the bar in a second position of the handle, and the
contact between the pin and the slot defines a range of travel of
the latch arm with respect to the handle.
[0006] A second representative embodiment of the disclosure
provides an oven. The oven includes a partially enclosed cooking
compartment defined by a frame with an inlet opening, the periphery
of the cooking compartment includes a bar. A pivotable door is
engaged with the housing to fully enclose the cooking compartment.
The door includes a pivotable latch arm. A first pin is pivotably
connected to the latch arm and a handle and a second pin extends in
parallel to the first pin and through a slot in the latch arm. The
latch arm and the handle are pivotably connected by the first pin
and the latch arm is pivotable by pivoting the handle with respect
to the door.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[0007] FIG. 1 is a perspective view of an oven with a releasable
door latch mechanism.
[0008] FIG. 2 is the oven of FIG. 1 with the doors removed.
[0009] FIG. 3 is a front perspective view of the door of FIG.
1.
[0010] FIG. 4 is a rear perspective view of the door of FIG. 1.
[0011] FIG. 5 is a front perspective view of the latch mechanism of
the oven of FIG. 1.
[0012] FIG. 6 is an exploded view of the components of the latch
mechanism of FIG. 5.
[0013] FIG. 7 is a top view of the latch mechanism of FIG. 5.
[0014] FIG. 7a is the view of FIG. 7, showing the latch arm in an
opening position.
[0015] FIG. 8 is a perspective view of the latch arm of the latch
mechanism of FIG. 5.
[0016] FIG. 9 is a perspective view of the cavity and bar of the
oven of FIG. 1.
DETAILED DESCRIPTION
[0017] Turning now to the figures, a baking oven 10 is provided.
The baking oven 10 includes a frame 20 that encloses a substantial
portion of a cooking volume 13 of the oven 10. The frame 20
additionally encloses a heat source 24 that is disposed within the
cooking volume 13. The heat source 24 may be provided from burners
that combust natural gas or other types of fuel to produce heat, or
from electric heaters that produce heat with current flow
therethrough due to their high internal resistance. The frame 20
may further enclose and support a fan 25 that provides air
circulation within the cooking volume 13 to evenly bake a food
product disposed within the cooking volume 13.
[0018] The cooking volume 13 is normally fully enclosed by at least
one door 30 that is pivotably mounted to the frame 20. In some
embodiments, two or more doors 30 may be pivotably mounted to the
frame 20 to enclose the cooking volume 13. The two or more doors 30
may each be independently openable, or in some embodiments, the two
or more doors 30 may be only operated in a specific sequence due to
the physical geometry of the doors 30 and their location with
respect to each other on the oven frame 20.
[0019] The door 30 is pivotably mounted to the frame 20 and movable
between an open position where the user can access the cooking
volume 13 of the oven 10 and a closed position (FIG. 1) where
access to the cooking volume 13 is prevented. The door 30 makes a
substantially hermetic seal with the frame 20 when in the closed
position, to limit the amount of heat and heated air that escapes
from the cooking volume 13 during operation when the door 30 is in
the closed position. A gasket, o-ring, or another similar type of
connection member 39 may be provided on one or both of the internal
surface 32 of the door 30 and the frame 20 to provide for a
suitable seal between the door 30 and the frame 20.
[0020] The door 30 is removeably retained in the closed position
with respect to the frame 20 with a latch mechanism 40. The latch
mechanism 40 is mounted to the door 30 to selectively provide and
remove a connection between a pivotable latch arm 50 and a bar 28
on the frame 20. In some embodiments, the latch mechanism 40 is a
single assembly that can be readily mounted or removed from the
door 30 using only one or two screws or other fasteners (not
shown). The latch arm 50 is mounted to an operator 44 that extends
outwardly (i.e. from the outer surface 31 of the door 30) from one
of the top or bottom surface 33, 34 of the door 30. The operator 44
is connected to a handle 90 that may be disposed parallel to the
door 30. The operator 44 (and the handle 90 connected thereto) is
pivotably connected to the door 30 and constrained by two shoulders
86a, 86b provided on a plate 86 that is disposed on the specific
top or bottom 33, 34 surface of the door 30. In some embodiments,
contact between the first and second shoulders 86a, 86b and the
operator 44 defines the range of motion of the operator 44 and the
handle 90 with respect to the door 30. For example, the first side
45a of the operator 44 normally contacts the first shoulder 86a to
limit the pivoting of the operator 44 due to the biasing force of
the spring 76 (discussed below). The operator 44 and the handle may
be pivoted until the second side 45b contacts the second shoulder
86, which limits the potential rotation of the latch arm 50 in the
direction Y (as shown on FIG. 7 and discussed below).
[0021] The operator 44 receives a first pin 60 that extends through
an aperture in the plate 86 and the latch arm 50 and is pivotably
mounted to a bracket 80 that is rigidly mounted to the door 30. In
some embodiments, the first pin 60 is rigidly mounted to the
operator 44 with a spline, a keyed connection, a weld joint, or
another suitable connection between the two members to prevent
relative pivoting. The bracket 80 is shaped and disposed within the
door to define and partially enclose an internal volume 80a that
receives and provides space for pivotal movement of the latch arm
50, a constraining bracket 70, a second pin 64, and a spring 76,
each of which are discussed below.
[0022] The first pin 60 extends through a first aperture 71 in the
constraining bracket 70, which is disposed below the plate 86. Each
of the first pin 60 and the constraining bracket 70 include holes
62, 73, respectively, that receive a dowel 74 when the two holes
62, 73 are coaxially aligned. The dowel 74 provides a removable
connection between the first pin 60 and the constraining bracket 70
to rigidly connect the two members together. The first pin 60
further extends through an aperture 52 in the latch arm 50 and
finally through an aperture (not shown) in the bracket 80.
[0023] In some embodiments, each of the apertures 52 of the latch
arm 50 and the bracket 80 may be formed with a larger diameter than
the first pin 60. Ball bearing assemblies 75a and 76a may be
received within the latch arm 50 and the bracket 80, respectively,
to provide pivotable and relatively friction free contact between
the first pin 60 and each of the latch arm 50 and bracket 80.
[0024] As best shown in FIG. 6, the first pin 60 may include two
grooves 62 spaced a slightly greater distance than the thickness of
the latch arm 50. The grooves 62 receive lock washers 76 to
constrain the placement of the latch arm 50 with respect to the
first pin 60.
[0025] The constraining bracket 70 includes a second aperture 72
spaced from and parallel to the first aperture 71. The second
aperture 72 receives a second pin 64 that is aligned parallel to
the first pin 60 and extends from the bottom surface 70b (i.e. the
surface pointing toward the latch arm 50) of the constraining
bracket 70. The second pin 64 is rigidly mounted to the
constraining bracket 70 with a spline, a keyed connection, a weld
joint, or another suitable connection method to prevent relative
movement between the two components. The second pin 64 extends
through an arcuate slot 54 defined in the latch arm 50, which
defines the potential range of relative pivoting between the latch
arm 50 and the constraining bracket 70 and operator 44.
[0026] A spring 76 (or another suitable biasing member) is disposed
within the internal volume 80a of the bracket 80 with a first end
connected to the latch arm 50 and a second opposite end connected
to the bracket 80 or another fixed portion of the door 30. The
spring 76 is aligned with respect to the latch arm 50 to bias the
latch arm 50 into the normal position (FIG. 7) position, and may be
stretched to allow the latch arm 50 pivot to the opening position
as shown on FIG. 7a.
[0027] The latch arm 50 includes a leg 55 that extends outwardly
from the body of the latch arm 50 and out of the internal volume
80a of the bracket 80. The leg 55 normally extends generally
perpendicularly from the internal surface 32 of the door 30 in the
closed position. The leg 55 includes a foot 56 that extends from
the leg 55 in a generally perpendicular manner. The foot 56
includes a chamfered edge 57 and a locking edge 58 that faces the
body of the latch arm 50. The chamfered edge 57 faces generally
away from the body of the latch arm 50 and forms an acute angle
.beta. with the locking edge 58 (as best shown in FIG. 8). The
chamfered edge 57 is positioned such that the chamfered edge 57
initially contacts the bar 28 on the oven frame 20 (discussed
below) as the door 30 pivots from the open position to the closed
position, and as discussed in detail below, as the chamfered edge
57 contacts the bar 28, the latch arm 50 pivots in a direction Z
toward the open position to allow the foot 56 to clear the bar 28
and the internal surface 32 of the door 30 to contact the frame
20.
[0028] As discussed above, the frame 20 includes an outer forward
surface 22 that receives the hinged connection with the door 30 and
provides a relatively hermetic and relatively low thermal
conductive connection between the door 30 and the frame 20. The
forward surface 22 of the frame 20 includes at least one cavity 26
which supports a vertically extending bar 28. The cavity 26
provides room for the foot 56 to enter therein and the locking edge
58 of the foot 56 to engage the back side of the bar 28 to prevent
the door 30 from pivoting from the closed to the open position.
[0029] In some embodiments, the door 30 may include two latch
mechanisms 40, with a first latch mechanism 40 positioned proximate
the top edge 33 of the door 30 and the second latch mechanism 40
positioned proximate the bottom edge 34 of the door 30. In
embodiments with two latch mechanisms 40 on a single door 30, the
handle 90 is connected to the operator 44 of each latch mechanism
40, such that pivoting of the handle 90 with respect to the door 30
causes both latch mechanisms 40 to move consistently. The frame 20
includes a similar number of cavities 26 and bars 28 that are
positioned to receive the foot 56 from each latch mechanism 40. In
some embodiments, two or more doors 30 are pivotably mounted to the
frame 20, wherein the frame 20 includes a suitable number of
cavities 26 and bars 28 to engage the number of latch mechanisms 40
provided on the two or more doors 30.
[0030] In operation, the door 30 may operated in the following
manner. When the operator desires to close the door 30 and
substantially enclose the cooking volume 13, the operator pushes or
pulls the handle 90 as necessary to pivot the door 30 toward
contact with the frame 20. As the door 30 reaches the closed
position, the chamfered edge 57 of the foot 56 of the latch arm 50
contacts the front surface of the bar 28. The contact between the
chamfered edge 57 and the bar 28 causes the latch arm 50 to pivot
in the direction Y due to the sliding contact established between
the chamfered edge 57 (FIG. 7) and the bar 28. As the latch arm 50
pivots in the direction Y, the spring 76 expands, allowing the
latch arm 50 to pivot but increasing the biasing force urging the
latch arm 50 to pivot in the opposite direction W.
[0031] As the latch arm 50 pivots with contact between the
chamfered edge 57 and the bar 28, the slot 54 of the latch arm 50
translates with respect to the second pin 64 that is maintained
stationary. Specifically, when the latch mechanism 40 is in its
normal position, the second pin 64 contacts the forward end 54a of
the slot 54 as urged by the spring 76. Because the latch arm 50
pivots in the direction Y independently of the handle 90, operator
44, and constraining bracket 70 (upon which the second pin 64 is
fixed), the slot 54 moves with respect to the second pin 64 until
the second pin 64 contacts the rear end 54b of the slot 54. At this
position, the latch arm 50 is prevented from further pivoting in
the direction Y unless the handle 90 is pivoted as well. The length
of the slot 54 is sized to allow the latch arm 50 and the foot 56
to pivot sufficiently to clear the bar 28 upon contact between the
chamfered edge 57 and the bar 28.
[0032] With sufficient sliding contact between the chamfered edge
57 and the bar 28 (which causes similar pivoting of the latch arm
50 in the direction Y) the foot 56 of the latch arm 50 moves free
of the bar 28, allowing the inner surface 32 of the door 30 to
contact the frame 20. After the foot 56 clears the bar 28, the
biasing spring 76 urges the latch arm 50 to pivot in the opposite
direction W until the foot 56 is positioned behind the bar 28.
Specifically, the locking edge 58 of the foot 56 contacts the inner
surface of the bar 28 (i.e. the surface facing the interior of the
cavity 26) and prevents the door 30 from opening or pivoting away
from the frame 20 by simply pulling outward on the door 30 or the
handle 90.
[0033] When the user desires to pivot the door 30 to the open
position, the user holds and pivots the handle 90 with respect to
the door 30 in the direction W while pulling the handle 90 in the
direction away from the door 30 (FIG. 3). As the handle 90 pivots,
the operator 44, the first pin 60, and the constraining bracket 70
similarly pivot due to the fixed connection between the operator 44
and the first pin 60, and the fixed connection between the first
pin 60 and the constraining bracket 70.
[0034] With rotation of the constraining bracket 70, the second pin
64 pivots through a similar arc and urges the latch arm 50 to
similarly pivot in the direction Y due to the contact between the
second pin 64 and the forward end 54a of the slot 54. As the latch
arm 50 pivots in the direction Y, the locking edge 58 of the foot
56 slides past the bar 28 until the foot 56 no longer contacts the
bar 28. When the foot 56 clears the bar 28, the door 30 becomes
free to be pulled from the frame 20 by the handle 90. After the
door 30 is pivoted away from the frame 20, the handle 90 may be
released, which allows the latch bar 50 to pivot in the direction W
under the biasing force of the spring 76. The leg 55 of the latch
arm 50 is retained substantially perpendicular to and extending
from the door 30 due to the contact between the first surface 45a
of the operator 44 and the first shoulder 86a.
[0035] While the preferred embodiments have been described, it
should be understood that the disclosure is not so limited and
modifications may be made without departing from the scope of the
disclosure. The scope of the invention is defined by the appended
claims, and all devices that come within the meaning of the claims,
either literally or by equivalence, are intended to be embraced
therein.
* * * * *