Door latch mechanism and associated components for a self-cleaning oven

Information

  • Patent Grant
  • 6601882
  • Patent Number
    6,601,882
  • Date Filed
    Friday, December 21, 2001
    23 years ago
  • Date Issued
    Tuesday, August 5, 2003
    21 years ago
Abstract
A door latching or locking mechanism or module for a self-cleaning oven includes latching linkage of the door latch module that enables use of lighter duty, less expensive motor. The mechanical advantage and vector optimization of the latching linkage avoids stalling especially from a locked position. The latching mechanism includes a plurality of switches having a corresponding plurality of terminals. The terminals are grouped or ganged to allow connection with a single connector interface. The switches are selectively actuable/de-actuable by a cam and cam plate that utilizes linear motion translated from rotational motion of a driven (motor) to selectively actuate and/or de-actuate the switches.
Description




FIELD OF THE INVENTION




The present invention relates generally to self-cleaning ovens, and more particularly, to a door latch mechanism and associated aspects thereof for self-cleaning ovens.




BACKGROUND




Ovens that are self-cleaning are well known. Such self-cleaning ovens include a cleaning mode or cycle that is initiated by a user. The self-cleaning cycle generates intense heat inside the oven. The intense heat reduces food particles, grease, spills and splatter (collectively, build-up) inside the oven to ash. Once the cleaning cycle is complete, the resulting ash may then be easily wiped away.




Because of the intense heat necessary to reduce such build-up to ash, self-cleaning ovens lock the oven door during the cleaning cycle to prevent access thereto. Self-cleaning ovens thus include a locking mechanism that keeps the oven door shut and locked during the cleaning cycle. While the locking mechanism may be manually actuated, most locking mechanisms in current self-cleaning ovens are automatically actuated when the self-cleaning mode is selected.




Such locking mechanisms include a latch that is controlled by the motor. The latch cooperates with a lock jamb in the door of the oven to lock the door when the door is in a closed position. The latch, via the motor, creates a compressive force between the door and the oven. This seals the oven door against the oven. Tolerance stack-up on doors, frames and hinges of the oven uses up the compressibility of the seal of the door and can cause current locking mechanisms to undesirably stall.




Current oven designs thus cause oven manufacturers to want a locking mechanism that has high strength and low cost. Strength or force has also begun to be associated with the position of the latch with respect to the door lock jamb. Higher strength or force for the locking mechanism translates into a higher cost. In order to lower the price for such locking mechanisms, force requirements have been eroded. Since over half the cost of such locking mechanisms is in the gear motor, reducing force requirements reduces the size of the motor necessary to achieve the required force by the latch. As an example, the following table (Table 1) illustrates how such force requirements have been eroded.















TABLE 1









Date




Stroke




Dimension Tolerance




Force











7/98




0.8″ 




0.075″




12 lbs






2/00




0.65″




0.100″




4 to 6 lbs






4/00




0.54″




0.090″




3 to 4 lb














It is known art to drive or actuate the latch of the locking mechanism directly from the motor of the locking mechanism via lock levers. However, even with the reduction of force requirements and such direct drive mechanisms, the problem of stalling of the latch is still present.




In addition to providing a latching function, current locking mechanisms provide switches that control various aspects of the oven associated with or because of the self-cleaning mode. The switches in such current locking mechanisms are actuated via a radial (drum) cam that is driven by the motor. A radial or drum cam has a thickness or stack in proportion to the number of switches associated with the locking mechanism. A problem with such radial cams is that the thickness (height) of the drum stack would become too large to package the many switches that are now part of the locking mechanism in a convenient ganged array if the drum stack is too large, the locking mechanism becomes too thick for useful or practical packaging for ovens.




Therefore, each one of the many switches located on the locking mechanism requires two terminals (a set of terminals). Each set of terminals needs to be coupled to a controller or other component of the oven. Currently, each terminal of each set of terminals is connected to the controller or other component via an individual spade connector. During assembly, each spade connector must therefore be connected individually. This can present a problem of correctly connecting the various spade connectors.




What is therefore needed is a door locking mechanism for a self-cleaning oven that overcomes the disadvantages of the prior art. What is further needed is a door locking mechanism for a self-cleaning oven that is low cost, provides enough strength (force) for door closure retention, provides little or no stall, accommodates a plurality of switches, and is low-profile. What is therefore further needed is a door locking mechanism for a self-cleaning oven that can be retrofitted into existing self-cleaning oven models.




SUMMARY




The present invention is a door latch mechanism and/or module for a self-cleaning oven. The door latch module is operative in one mode to securely latch or catch the oven door and in another mode to allow free movement of the oven door. The door latch module is adapted to be automatically driven. The door latch module includes and/or performs various features and/or functions.




According to an aspect of the subject invention, the door latch module includes reciprocating mechanical latching linkage that drives a latching hook. The latching hook cooperates with a latch catch in the oven door to retain the oven door in the one mode of operation. The mechanical latching linkage is configured as common pivot arms that provide a scissors action that reciprocates through a drive arm. The drive arm is coupled to a rotating member. Rotational movement of the rotating member is translated into near-linear, planar movement (latching movement) of the latching hook through the drive arm and the pivot arms.




In this manner, a class N (or other) motor may be used as a driver. Additionally, the latching linkage is configured to decrease latch speed at clamping or latching point. This increases the mechanical advantage at a clamping. As well, the likelihood of stalling is reduced. Further, the present latching linkage requires less torque to operate.




According to another aspect of the subject invention a door latch module includes a plurality of switches. The plurality of switches, in turn, have a corresponding plurality of terminals. The plurality of terminals for the door latch module are ganged or grouped to permit coupling with a single terminal interface. The single terminal interface may be configured to accept a modular plug. The modular plug may include releasable catches or the like.




According yet to another aspect of the subject invention, a door latch module includes a cam plate that is operative to selectively actuate and/or de-actuate select switches of the plurality of switches. The cam plate is driven by a driver (such as a motor) during the cleaning cycle or mode. The cam plate translates rotational motion of the motor to linear motion to actuate and/or de-actuate the switches.




In one form, the subject invention is a latch mechanism for a self-cleaning oven. The latch mechanism includes a support, a rotational member maintained by the support, and latch linkage maintained by the support. The latch linkage is coupled to the rotational member and has a hook operative to move into a first position and into a second position during rotation of the rotational member. The latch linkage includes a scissors mechanism coupling the rotational member with the hook.




In another form, the subject invention is a latch mechanism. The latch mechanism includes a rotating member and a drive arm having a first end connected to the rotating member and a second end. The latch mechanism further includes first and second coupling arms each having a first end connected to the second end of the drive arm at an interconnection, and an L-bracket having a first end rotatably mounted to a first fixed pivot point and having a second end for engaging a latch member. A second end of the first coupling arm is connected to the L-bracket and a second end of the second coupling arm is rotatably mounted to a second fixed pivot point. The interconnection is rotatable around a connecting member that floats in association with movement of the rotating member.











BRIEF DESCRIPTION OF THE DRAWINGS




The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following descriptions of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:





FIG. 1

is a perspective view of an oven embodying various inventions according to the principles presented herein;





FIG. 2

is a perspective view of the oven of

FIG. 1

with a partial cutaway section showing an exemplary door latch mechanism and/or module in communication with an oven controller;





FIG. 3

is a top perspective view of an exemplary door latch module;





FIG. 4

is a bottom perspective view of an exemplary door latch module;





FIG. 5

is a side view of an exemplary door latch module;





FIG. 6

is an enlarged partial cutaway view of a plurality of terminals associated with an exemplary door latch module;





FIG. 7

is a bottom plan view of an exemplary door latch module showing positioning of latching linkage thereof when in a fully open or unlatched position;





FIG. 8

is a bottom plan view of an exemplary door latch module showing positioning of the latching linkage thereof when in a fully closed or latched position;





FIG. 9

is a schematic representation of the reciprocating motion of the latching linkage during a full cycle thereof;





FIG. 10

is a graph of the representation of the reciprocating motion of the latching linkage depicted in

FIG. 9

particularly illustrating the various positions of a hook associated with the latching linkage with respect to latching and unlatching an oven door and with respect to a typical oven door latch;





FIG. 11

is a top perspective view of an exemplary door latch module with the motor removed;





FIG. 12

is a top perspective view of an exemplary door latch module with the latching linkage in a fully open position and with the cover and motor removed particularly showing positioning of the cam and cam plate;





FIG. 13

is a top perspective view of an exemplary door latch module with the latching linkage in a fully closed position and with the cover and motor removed particularly showing positioning of the cam and cam plate;





FIG. 14

is an enlarged side perspective view of an exemplary door latch module particularly showing the cam and cam plate relative to the switches when the cam and cam plate are in an open or unlatched position;





FIG. 15

is an enlarged side perspective view of an exemplary door latch module particularly showing the cam and cam plate relative to the switches when the cam and cam plate trace are in a closed or latched position;





FIG. 16

is a schematic representation of an exemplary embodiment of the various switches of the door latch module particularly depicting the switches in a door closed position;





FIG. 17

is a schematic representation of an exemplary embodiment of the various switches of the door latch module coupled in relation to the oven controller and motor;





FIG. 18

is a schematic representation of another exemplary embodiment of the various switches of the door latch module coupled in relation to the oven controller and motor;





FIG. 19

is a schematic representation of an exemplary embodiment of the various switches of the door latch module particularly depicting the exemplary positioning of the switches and coupled in relation to the oven controller and the motor;





FIG. 20

is a schematic representation of an exemplary manner of coupling and the function and/or operation of a switch of the door latch module;





FIG. 21

is a schematic representation of an exemplary manner of coupling and the function and/or operation of a switch of the door latch module;





FIG. 22

is a schematic representation of an exemplary manner of coupling and the function and/or operation of a switch of the door latch module;





FIG. 23A

is a schematic representation of an exemplary manner of coupling and the function and/or operation of a switch configuration of the door latching module; and





FIG. 23B

is a schematic representation of the exemplary manner of coupling and the function and/or operation of the switch configuration of FIG.


23


A.




Corresponding reference characters indicate corresponding parts throughout the several views.











DETAILED DESCRIPTION




Referring to

FIG. 1

, there is depicted an oven, range, or stove (and as used hereinafter, collectively oven) generally designated


10


, representing all forms of ovens, ranges, and stoves in which the subject inventions may be embodied. The oven


10


has a frame or body


12


that defines an oven portion or cooking chamber


14


. The cooking chamber includes cooking elements (not shown) such as resistive heating elements, or the like such as is known. A door


16


is attached to the frame


12


by at least two hinges


18




a


and


18




b


that extend into the frame


12


. The door


16


is adapted to open and close relative to the cooking chamber


14


. Particularly, the door


16


is adapted to pivot into open and closed positions relative to the cooking chamber


14


. The hinges


18




a


and


18




b


extend into the frame


12


and are configured to allow the door


16


to open and close. The hinges


18




a


and


18




b


also stop movement of the door


16


at the position shown in

FIG. 1

(a fully open position). While not shown, the door


16


may include a longitudinal hinge along a bottom edge of the door


16


between the hinges


18




a


and


18




b


that is attached to the frame


12


.




The door


16


has an inset portion


20


that is sized to fit the opening of the cooking chamber


14


. The door


16


also includes a raised rim


22


that is disposed about the inset portion


20


. The raised rim


22


is configured to abut a ledge


24


that is inset from and surrounds the perimeter of the opening of the cooking chamber


14


. The raised rim


22


and/or the ledge


24


preferably have a compressive seal (not shown) thereabout that abuts the other when the door


16


is in a closed position. When the door


16


is in the closed position, the raised rim


22


abuts the ledge


24


while the inset portion


20


extends into the cooking chamber


14


. In this manner, heat produced within the cooking chamber


14


tends to stay therein with minimal to no heat loss or leakage from or about the door


16


.




The door


16


may also include hook mechanisms


28




a


and


28




b


disposed on upper corners of the door


16


that correspond to hook receiving mechanisms


30




a


and


30




b


in the frame


12


. The hook receiving mechanisms


30




a


and


30




b


are positioned in the frame


12


proximate the cooking chamber


14


to receive the respective hook mechanism


28




a


and


28




b


of the door


16


, when the door


16


is closed. The hook mechanism


28




a


and


28




b


may be coupled to or associated with the handle


26


so as to operate in conjunction therewith. One form, movement of the handle


26


moves the hook mechanisms


28




a


and


28




b


which cooperate with the hook receiving mechanisms


30




a


and


30




b


when the door


16


is in the closed position to releasably maintain the door


16


to the frame


12


. In this example, movement of the handle


26


during opening of the door


16


releases the hook mechanisms


28




a


and


28




b


from the hook receiving mechanism


30




a


and


30




b


respectively to allow opening of the door


16


relative to the frame


12


and cooking chamber


14


.




The oven


10


also includes a top surface


42


that supports four (4) burners or heating elements


44


of any type (i.e. resistance, induction, or the like). It should be appreciated that there may more or less burners or elements as desired by the manufacturer but four are typical. Adjacent the top surface


42


is a console


52


that supports four controllers


46


, one for each burner. Each controller


46


is operative to turn on and off a burner as well as set the temperature thereof. The console


52


also supports a clock


48


and a control/selector panel


50


. The control/selector panel


50


is operative to allow the user to select various modes of the oven


10


and display various information regarding those modes and/or cycles of the range in general. More particularly, the control selector panel


50


is operative to allow the user to set, without being exhaustive, such modes as the cleaning cycle, baking, broiling, temperature setting/control for baking broiling, and the like.




With additional reference to FIG.


2


and in accordance with an aspect of the subject invention, the oven


10


also includes a door latch mechanism or module


32


(hereinafter collectively, module). The door latch module


32


is typically, and as shown herein, mostly disposed within the frame


12


. As particularly shown herein, the door latch module


32


is behind the front panel


40


and under the top surface


42


. It should be appreciated that while the door latch module


32


is shown disposed at a front side of the oven


10


, the door latch module


32


may be situated at a rear side of the oven


10


. The door latch module


32


may be thought of as modular. This allows the present door latch module


32


to retrofit existing door latch mechanisms.




The door latch module


32


is operative to secure and/or securely latch the door


16


against the frame


12


when the oven


10


is in the cleaning mode/cycle in order to keep the door


16


about the cooking chamber


14


. When the oven


10


is not in the cleaning mode/cycle, the door latch module


32


is operative to allow the door


16


to freely open and close relative to the cooking chamber


14


. The door latch module


32


is under control of the oven


10


as described in greater detail below.




The door latch module


32


is in communication with a main controller, control logic/circuitry, processor, processing unit, processing circuitry/logic and/or control board


54


(hereinafter collectively, main controller) of the oven


10


via a communication line or conductor such as cable


56


. The cable


56


has a plurality of wires, electrical conductors, and/or optic conductors (hereinafter collectively, conductors) that terminate at one end in a single housing interface


58


(e.g. and hereinafter, a modular plug) and at another end in another preferably single housing interface


60


(e.g. and hereinafter, a modular plug). The modular plug


58


and or the modular plug


60


may be a quick connect/disconnect type plug. This aids in reducing and/or eliminating wiring mix-ups as compared to single spade type connectors.




The modular plug


58


is coupled to the door latch module


32


while the modular plug


60


is coupled to the main controller


54


. More particularly, and as described in greater detail below, the modular plug


58


has a plurality of connecting conductors that releasably couple to a plurality of terminals of the door latch module


32


. As described in greater detail below, the plurality of terminals (see e.g.

FIG. 3

) of the door latch module


32


are coupled to switches and/or other components thereof. The modular plug


60


likewise has a plurality of connecting conductors that releasably couple to a plurality of terminals (not shown) of the main controller


54


. The plurality of connectors of the main controller


54


are coupled to the various components and/or circuitry/logic of the main controller


54


. The main controller


54


is in communication with the control/selector panel


50


, the controllers


46


, and other various components as are typical of ovens and/or similar appliances.




The door latch module


32


has a door position pin


34


that is part of a door position switch


35


. The door position pin


34


extends from the door position switch


35


through a hole


72


in the front panel


40


(see FIG.


3


). The door position pin


34


is operative to detect position of the door


16


. Particularly, the door position pin


34


is operative to detect whether the door


16


is closed (i.e. the door


16


rests against the frame


12


and covers the cooking chamber


14


) and/or whether the door


16


is open (i.e. the door


16


ranges from being ajar a small distance from and relative to the frame


12


to being fully open and down). While the opposite may be applied to the present case, the door position pin


34


is shown and assumed herein to be biased outward toward the door


16


. The door position switch


35


via the door position pin


34


is thus operative to indicate whether the door


16


is open or closed.




In the present case, contact of the door


16


against the door pin


34


actuates the door position switch (either opens or closes the door switch


35


depending on the electrical configuration of the switch, i.e. a normally-open or normally-closed type switch). The opening or closing of the door position switch


35


by actuation of the door


16


against the door position pin


34


, provides a door open/close signal to the main controller


54


. It should be appreciated that the door position switch


35


/door position pin


34


may take other forms that indicate whether the door is open.




The door latch module


32


includes a latch, latching, or hook mechanism


62


(hereinafter and collectively, latch mechanism


62


) that is in communication with a motor


64


(see, e.g. FIG.


3


). The latch mechanism


62


is driven by the motor


64


(i.e. the latch mechanism


62


moves through movement of the motor


64


). The latch mechanism


62


includes a hook or hook portion


36


. The hook


36


normally extends from a slot


38


in the front panel


40


of the oven


10


. The door


16


includes an opening


37


in which is disposed a bar or the like


39


that is positioned so as to be adjacent the slot


38


when the door


16


is closed. When the door


16


is closed and the oven


10


is in a normal operating mode (i.e. not in the cleaning mode/cycle), the hook


36


extends slightly into the opening


37


but does not engage the bar


39


. The motor


64


causes the hook


36


, via the latching mechanism


62


to engage the bar


39


when the oven


10


is put into the cleaning mode. When the cleaning mode is complete, the hook


36


is caused to disengage the bar


39


via the motor


64


acting on the latching mechanism


62


. Thereafter, the hook


36


returns to its normal position.




Power for the oven


10


is provided via a power cord (not shown) that is configured to be plugged into an appropriate source of electricity (i.e. a line voltage), typically a 120 volt AC source or a 240 volt AC source (not shown). The various components of the oven


10


are thus configured, adapted, and/or operative to operate on the line voltage or an appropriately transformed power (voltage and/or current) by appropriate transformers and/or transformer circuitry/logic.




Referring to

FIGS. 3-6

, there is shown the door latch module


32


from various angles. In particular,

FIG. 3

depicts a perspective view of one side of the door latch module


32


,

FIG. 4

depicts a perspective view of another side of the door latch module


32


,

FIG. 5

depicts a side view of the door latch module


32


, and

FIG. 6

depicts an enlarged perspective view of a terminal bank of the door latch module


32


in accordance with an aspect of the present principles.




The door latch module


32


has a housing


65


that is shown in an exemplary manner as a plate


66


. The plate


66


defines a support or frame for at least some of the various components of the door latch module


32


. The door latch module


32


may thus be considered as a module or component of the oven


10


. As shown in

FIG. 2

, the plate


66


is adapted and/or configured to be mounted to the frame


12


of the oven


10


. The plate


66


has a front flange or side


68


that defines an essentially flat face or surface. The front flange


68


is essentially perpendicular to a plane defined by the plate


66


. A slot


70


is formed in the flange


68


that is sized, configured, and/or adapted to allow the hook


36


to extend therethrough. The slot


70


is of a height and longitudinal length that allows the movement of the hook


36


within the slot


70


. Particularly, the slot


70


is configured to allow the hook


36


to move in a side-to-side direction (longitudinal direction) therein as well as in and out relative to the face of the flange


68


(essentially perpendicular to the longitudinal length of the slot


70


). As discussed in detail below, movement of the hook


36


is accomplished during the cleaning mode or cycle of the oven


10


.




The flange


68


also has an opening


72


through which extends the door pin


34


of the door switch


35


. The opening


72


is sized and/or configured to allow the reciprocal movement of the door pin


34


therethrough. The door pin


34


is biased into either an open-switch or closed-switch position depending on the type of switch and its wiring and/or application. As best seen in

FIGS. 1 and 2

, the pin


34


in the present example is biased into an open-switch position. In this manner, the pin


34


is normally out (extended) when the door


16


is open, and in (depressed) when the door


16


is closed.




The flange


68


further includes mounting holes or bores


74


that are adapted and/or configured to allow screws, bolts, or other fasteners (not shown) to extend therethrough and be held by the flange


68


. The mounting holes


74


and the fasteners cooperate to allow the door latch module


32


to be mounted to the oven


10


. Particularly, the flange


68


abuts the inside surface (not shown) of the panel


40


when the locking mechanism


32


is mounted to the oven


10


.




The plate


66


also has a first side extension


76


and a second side extension


82


that is opposite the first side extension


76


. The first and second side extensions


76


and


82


are essentially perpendicular to the plane defined by the plate


66


. The first side extension


76


has a first outward flaring flange


78


that includes mounting holes


80


that are adapted and/or configured to allow screws, bolts, or other fasteners (not shown) to extend therethrough and be held by the flange


78


. The mounting holes


80


and the fasteners cooperate to allow the door latch module


32


to be mounted to the oven


10


. The second side extension


82


has a second outward flaring flange


84


that includes mounting holes


86


that are adapted and/or configured to allow screws, bolts, or other fasteners (not shown) to extend therethrough and be held by the flange


84


. The mounting holes


86


and the fasteners cooperate to allow the door latch module


32


to be mounted to the oven


10


. As shown in

FIG. 2

, the plate


66


(and thus the door latch module


32


) is adapted to be mounted to the oven


10


adjacent the front panel


40


via the mounting holes


74


,


80


, and


86


of the flanges


68


,


78


, and


84


respectively. It should be appreciated that the mounting configuration is only exemplary of a manner in which the door locking mechanism


32


is mountable to the oven


10


. Other mounting configurations are thus contemplated.




As best seen in

FIG. 3

, the door latch module


32


also has a motor


64


that is situated over a cover


88


. The motor


64


is electrically coupled to various and appropriate terminals


98


of the terminal bank


100


(see

FIG. 6

) in order to receive electricity and/or control signals. As described further below, the motor


64


provides a driving mechanism or driver for various features and/or mechanisms of the door latch module


32


. With reference to

FIG. 6

, the terminals


98


are held via a retainer


96


within or flush with an opening


90


of the cover


88


. The opening


90


and/or the retainer


96


define a single terminal interface for the door latch module


32


. The single terminal interface may be embodied in a modular plug, connector, or the like. The modular plug is preferably a quick connect/disconnect type, however, any suitable type of plug or connector may be used.




In

FIG. 4

, the latch mechanism


62


is more particularly shown. The latch mechanism


62


may also be thought of as latch or latching linkage. The latching linkage


62


is formed of various members or links that are pivotally and/or fixedly coupled in the manner shown in the figures and/or described herein. The latching linkage


62


is coupled to the motor (driver)


64


via a motor shaft


108


that defines an axis of rotation. Particularly, the latching linkage


62


is coupled to the motor


64


via a rotational or rotating member


104


. The rotating member


104


may be a disk or a cam. A drive arm link


102


is pivotally fixed at


106


to the rotating member


104


. The drive arm link


102


reciprocates substantially back and forth as the rotating member


104


rotates.




The drive arm link


102


is pivotally coupled at


116


to a scissors mechanism or linkage


110


. The scissors mechanism


110


is in turn pivotally coupled to a hook arm


122


and swing arm


124


, with the hook arm


122


terminating in the hook


36


. The scissors mechanism


110


includes a first link arm


112


that is pivotally attached at one end to a fixed point


114


so as to pivot or swing therefrom, and at a second end to the pivot


116


. The scissors mechanism


110


also includes a second link arm


118


that is preferably fixed at but may be pivotally attached at one end to a pivot


120


, and at another end at the point (pivot)


116


. The swing arm


124


is pivotally (but may be fixedly or as a piece integral with the hook arm


122


) coupled at one end thereof to the hook arm


122


distal the hook


36


and pivotally coupled to one another and the second arm


118


. The swing arm


124


is further pivotally coupled at another end to a fixed point


126


. The swing arm


124


further includes a stop


125


that prevents travel of the hook arm


122


too far thereagainst.




As the rotating member


104


rotates in response to being driven by the motor


64


, the drive arm


102


pulls and pushes the scissors mechanism


110


via the pivot


116


. The second arm


118


thus pulls and pushes the hook arm


122


against the bias of the spring


130


and the swing arm


124


. Movement of the hook arm


122


provides movement of the hook


36


as detailed further below. The motion is reciprocating since the rotating member


104


rotates.




With additional reference to

FIGS. 7 and 8

, it should be appreciated that the rotating member


104


rotates or is driven by the motor


64


in response to the oven


10


beginning, completing, or ending the cleaning cycle/mode. The rotating member


104


thus completes a full 360° rotation upon completion of the cleaning cycle/mode. Particularly, the position of the pivot


106


defines, in this example, a start position or 0°. This corresponds to the hook


36


being in a stowed or unlatched position as depicted in

FIGS. 4 and 7

. When the rotating member


104


has rotated 180° as depicted in

FIG. 8

, the hook


36


is in the latched position. The various angular positions of the rotating member


104


between 0° and 180°, and between 180° and 360° thus move the hook


36


into the next position.




The hook arm


122


includes a spring retainer


132


while the swing arm


124


includes a spring retainer


134


. A biasing spring


130


(here a compression spring) is used to maintain the hook


36


in an unlatched position or pulled against the swing arm


124


. In this manner, the hook arm


122


and thus the hook


36


are normally biased into an unlatched position.




The latching linkage


62


in accordance with an aspect of the subject invention thus moves the hook


36


from an unlatched position or mode to a latched position or mode and vice versa. The latching linkage


62


is thus operative, configured, and/or adapted to latch and unlatch the oven door


16


particularly during and after the cleaning cycle of the oven


10


.




Referring to

FIGS. 9 and 10

there is shown a representation of the movement of the latch mechanism


62


. Particularly, the movement of the hook


36


relative to the rotational member


104


and the linkage components is shown and graphed for a full cleaning cycle or mode. In

FIG. 9

it can be seen that the as the pivot point


106


rotates with the rotational member


104


(as driven by the motor


64


) the hook


36


undergoes displacement in accordance with the hook movement/displacement curve


140


wherein position “A” corresponds to a full unlatched position, and position “B” corresponds to a full latched position. The latching linkage, including the scissors mechanism, floats when operating. The latching linkage is coupled to or part of the hook


36


. The two arms of the embodiment of the scissors mechanism shown and described herein are pivotally coupled to one another at ends thereof in a free or floating manner (i.e. the pivot is not fixed relative to the arms). One arm of the scissors mechanism of the latching linkage is pivotally fixed at another end thereof to the support, while the other end of the other arm of the scissors mechanism is pivotally coupled to the hook member.




The curve


140


is graphed in FIG.


10


and reference is now made thereto. The curve


140


is graphed as displacement (the Y-axis) versus time (the X-axis). A second curve


142


for a prior art direct driven latch mechanism is also shown for comparison. The hook


36


starts in an unlatched or unlocked position, position “A”. The scissors mechanism


110


causes the curve to begin tightening around 60°. At 0° (position “B”, corresponding to the latched or locked position) the present hook


36


provides compressive latching with little displacement at or below the displacement reference (the X-axis). In contrast, the curve


142


indicates that stalling may start to occur at about 15° through 0° (during the locking position). Thereafter, the present hook


36


travels to an unlatched position, position “A”. Again, in contrast, the curve


142


indicates that stalling may still occur during movement out of the locked position from 0° to about 15°.




Referring to

FIGS. 11-15

other aspects of the door latch module


32


will now be described. The door latch module


32


includes a cam plate


150


that is driven by a cam


154


. The cam


154


is, in turn, driven by the motor


64


. The cam plate


150


is linearly movable on the plate


66


in accordance with the position of the cam within a cam opening


152


in the cam plate


154


. As the motor


64


rotates, the cam


154


is likewise rotated. Rotation of the cam


154


linearly translates the cam plate


150


in a reciprocal movement.




The cam plate


150


includes a plurality of tracks, channels, or grooves


158


in which is disposed an actuator


156


. Preferably, the actuators


156


are movably settable along their respective track


158


. The number of tracks corresponds to the number of switches or terminal pairs of the bank of terminals


100


. One set of terminals (here shown as the lower pair) includes actuators or prongs


160


, while the other set of terminals (here the upper pair) includes contacts


162


. The terminal pairs are spaced apart such appropriate movement of the lower terminal makes contact with the upper terminal to complete the switch. The lower terminal is caused to move upward when an actuator


156


is caused to move under a prong


160


through sliding movement of the cam plate


150


.




The cam plate


150


moves as the latch linkage


62


moves. During this time various switches are preferably actuated by the actuators


156


to cause various signals to be generated to control various features and/or components. Since each actuator


156


is movable along its respective track


158


, each switch, through its respective terminal pairs, may be controlled as to when it is actuated within the 360° rotation of the rotational member


104


.




In

FIGS. 12-15

, there is depicted the cam


154


and the cam plate


150


when the latch mechanism


62


is in the unlatched position (

FIGS. 12 and 14

) and the latched position (FIGS.


13


and


15


). It can be seen that the cam plate


150


moves in a linear motion in response to the cam


154


between the unlatched position and the latched position. The cam plate


150


moves or reciprocates from one extreme position (unlatched) to another extreme position (latched), in response to a clean cycle mode or command. This can be equated with 0° through 180° (from the unlatched to the latched position) and from 180° to 360° (from the latched to the unlatched position). As well, it can be seen that the cam operated switches open and close in response to the cam actuators


156


associated with each switch. Rotational movement of the cam


154


from the motor


64


is translated into linear movement (translation) through the cam plate


150


.




Referring to

FIG. 16

, there is depicted an exemplary schematic embodiment of various switches of the present door latching mechanism


32


. In the exemplary embodiment of the door latching mechanism


32


, there are six (6) switches generally labeled S


1


, S


2


, S


3


, S


4


, S


5


, and S


6


. Four (4) of the switches S


1


, S


2


, S


3


, and S


4


are actuated by the cam


154


and cam plate


150


(collectively “cam actuated”), while two (2) of the switches S


5


and S


6


are actuated by the door position pin/switch


34


/


35


. In

FIG. 16

, the switches are shown in a door closed position. The various switches S


1


-S


4


are coupled to the controller


54


and/or motor


64


to provide selective actuation of the features/functions as described herein.




When the door


16


is closed, the door position pin (plunger)


34


actuates the door position switch


35


such that the switches S


5


and S


6


are closed. The cam operated switches S


1


, S


2


, S


3


, and S


4


have been positioned as closed, open, open, and closed respectively, via the respective actuators


156


of the cam plate


150


.




In

FIG. 17

, there is depicted a specific exemplary connection of the switches shown in FIG.


16


. Particularly, the switch S


5


provides a signal (via being in communication with a voltage source of +5 volts) to the controller


54


(control circuitry


54




a


) that the door


16


is closed. As well a cam operated switch S


1


is closed to provide a signal from the control circuitry


54




a


to the motor


64


to move the latch linkage into the closed position. The switch S


3


is not yet closed by an actuator


156


of the cam plate


150


which, when it does, provides a signal to the control circuitry


54




a


that the latch is locked. The switch S


2


will close and the switch S


1


will open when the latching linkage is to unlock the door


16


. In this manner the motor


64


will then continue to drive the latching linkage and cam plate.




In

FIG. 18

, the particulars of the controller


54


for the schematic of

FIG. 17

are shown in greater detail. Additionally, the switches are laid out differently for additional ease in understanding. The switch S


4


provides a signal to lights and fans logic/circuitry


166


that is operative to disable the lights and/or fans of the oven


10


during the clean cycle. The switch S


5


provides a door position indication signal to circuitry/logic


170


that is operative to open and close a contact K


1


(such as a solenoid or the like) to respectively start and stop the motor


64


and lock and unlock the door


16


. The switch S


3


provides a latched locked position indication signal to circuitry/logic


168


that is operative to start the cleaning cycle, cool down during the cleaning cycle, and unlock the door


16


. The circuitry/logic


168


actuates a contact K


2


(such as a solenoid or the like) to allow the motor


64


to operate and not operate.




In

FIG. 19

, there is depicted another layout of the cam operated switches S


1


, S


2


, S


3


, and S


4


, and the door position operated switches S


5


and S


6


in relation to the controller


54


and the motor


64


. The switches are shown in the clean mode with the legend in

FIG. 19

indicating switch control/signal generation for the door latch module


32


.





FIG. 20

illustrates another exemplary manner in which one of the switches, here switch S


2


(SW


2


) provides a signal to the control logic


54


. The switch S


2


is a cam operated switch that indicates (via a signal) to the control logic


54


when it is time to clean, cool down, and generate and send a signal to unlock the door


16


. It should be appreciated that the cam operated switches S


1


-S


4


may open and close depending on the positioning of the respective actuator


156


and the movement of the cam plate


150


.




In

FIG. 21

, exemplary particulars are provided with regard to switch S


5


. Switch S


5


is from the door position switch


35


and provides a door position signal to the controller


54


. In

FIG. 21

, the switch S


5


is closed indicating a door closed condition. This causes the controller


54


to close contacts to start the motor


64


and lock/latch the door


16


via the latching linkage. When switch S


1


(a cam operated switch) closes while the switch S


5


is closed, the motor


64


can thereafter start.




In

FIG. 22

exemplary particulars are provided with regard to switch S


3


. Switch S


3


is a cam operated switch and is opened when the door


16


unlocks or unlatches. The switch S


3


provide a signal to the controller


54


regarding whether to enable or disable the light(s) and/or fan(s) and/or circuitry/logic thereof.




Referring now to

FIGS. 23A and 23B

, there is provided another exemplary particular regarding the door actuated switches, here switches S


1


and S


2


, and a cam operate switch S


3


. Particularly, the switches S


1


, S


2


, and S


3


are shown in the clean mode or cycle. Switch S


2


provides a signal to start and operate/run the motor


54


when the door


16


is closed. Switch S


1


provides a door closed signal to the fan/light circuitry/logic


166


. The fan/light circuitry/logic


166


provides a signal via switch S


3


, when closed as shown, to oven light(s) circuitry/logic


172


to disable the oven lights.




It should be appreciated that the schematics of

FIGS. 16-23

are exemplary of a manner in which the switches of the present door latch module


32


may be wired and function/operate. Other wiring may be used and is contemplated to carry out the various functions, features, and or operations described herein.




In sum, the door latch module


32


is operative to move the hook


36


from a stowed or unlatched position to a locked or latched position through actuation of the motor


64


via latch linkage in communication with the motor


64


and part of the hook


36


. Various switches associated with the door latch module


32


are actuated by the motor


64


via a cam and cam plate.




While this invention has been described as having a preferred design, the subject invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the subject invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and that fall within the limits of the appended claims.



Claims
  • 1. A latch mechanism comprising:a rotating member; a drive arm having a first end connected to the rotating member and a second end; first and second coupling arms each having a first end connected to the second end of the drive arm at an interconnection; and an L-bracket having a first end rotatably mounted to a first fixed pivot point and having a second end for engaging a latch member; wherein a second end of the first coupling arm is connected to the L-bracket, a second end of the second coupling arm is rotatably mounted to a second fixed pivot point, and the interconnection is rotatable around a connecting member that floats in association with movement of the rotating member.
  • 2. The latch mechanism of claim 1, further comprising a frame comprising the first and second fixed pivot points.
  • 3. The latch mechanism of claim 1, wherein the interconnection is located outside the L-bracket.
  • 4. The latch mechanism of claim 1, wherein the L-bracket comprises a first curved arm that includes the first end of the L-bracket.
  • 5. The latch mechanism of claim 4, wherein the curved arm comprises a swing arm and a hook arm.
  • 6. The latch mechanism of claim 4, wherein the curved arm has a curved shape that curves in a direction toward the rotation member.
  • 7. The latch mechanism of claim 4, wherein the curved arm has a curved shape that approximates a curved shape of the rotating member.
  • 8. The latch mechanism of claim 6, wherein the curved arm comprises a portion with a radius centered at a center of the rotating member.
  • 9. The latch mechanism of claim 1, wherein the L-bracket comprises a curved portion that includes the first end of the L-bracket and a non-curved portion.
  • 10. The latch mechanism of claim 8, wherein the curved portion and non-curved portion are separate pieces joined together.
  • 11. The latch mechanism of claim 1, further comprising a switch assembly activated by movement of the rotating member.
  • 12. The latch mechanism of claim 1, further comprising a motor for driving the rotating member.
  • 13. The latch mechanism of claim 11, further comprising a frame comprising the first and second fixed pivot points.
  • 14. The latch mechanism of claim 13, further comprising an electrical connector assembly connected to the switch assembly for passing electricity through the switch assembly.
  • 15. The latch mechanism of claim 14, further comprising a motor for driving the rotating member, and a motor mounting frame.
  • 16. The latch mechanism of claim 1, wherein the second end of the L-bracket comprises a latch lever.
  • 17. A latch mechanism for a self-cleaning oven comprising:a support; a rotational member maintained by said support; latch linkage maintained by said support and coupled to said rotational member, said latch linkage having a hook on a hook member operative to move into a first position and into a second position during rotation of said rotational member, the latch linkage including a scissors mechanism coupling the rotational member with said hook member, wherein said scissors mechanism comprises (i) a first arm having a first end, (ii) a second arm having a first end, (iii) said first and second arms pivotally connected at said first ends, and (iv) said first arm further having a second end pivotally fixed to said support; and a drive arm coupled to said rotational member and said pivotal connection of said first ends of said first and second arms.
  • 18. A latching mechanism for a self-cleaning oven comprising:a support; a motor maintained on said support; a hook member maintained on said support and operative to be in a latched position and an unlatched position; and latch linkage operatively coupling said motor with said hook member and adapted to actuate said hook member into said latched and unlatched positions, said latch linkage including a scissors mechanism coupling said motor with said hook member, wherein said scissors mechanism comprises (i) a first arm having a first end, (ii) a second arm having a first end, (iii) said first and second arms pivotally connected at said first ends, and (iv) said first arm further having a second end pivotally fixed to said support; and a drive arm coupled to said rotational member and said pivotal connection of said first ends of said first and second arms.
  • 19. A self-cleaning oven, comprising:a motor operable to rotate a drive member in response to said oven being placed in a self-cleaning mode of operation; a latch mechanism movable from an unlatched position to a latched position in response to rotation of said drive member, said latch mechanism including: a latch housing; a drive link having (i) a first end portion movably coupled to said drive member, and (ii) a second end portion; a first link arm having (i) a first end portion pivotally coupled to said latch housing, and (ii) a second end portion pivotally coupled to said second end portion of said drive link; a second link arm having (i) a first end portion, and (ii) a second end portion pivotally coupled to said second end portion of said drive link; a latch arm having (i) a first end portion having a locking contact portion, and (ii) a second end portion pivotally coupled to said first end portion of said second link arm; and a swing arm having (i) a first end portion pivotally coupled to said latch housing, and (ii) a second end portion pivotally coupled to said first end portion of said second link arm.
  • 20. The self-cleaning oven of claim 19, wherein said locking contact portion of said latch arm includes a hook.
  • 21. The self-cleaning oven of claim 19, further comprising an oven door having a lock bar, wherein:said locking contact portion of said latch arm is spaced apart from said lock bar of said door when said latch mechanism is located in said unlatched position, and said locking contact portion of said latch arm is positioned in contact with said lock bar of said door when said latch mechanism is located in said latched position.
  • 22. The self-cleaning oven of claim 19, wherein 180° of rotation of said drive member causes said latch mechanism to be moved from said unlatched position to said latched position.
  • 23. The self-cleaning oven of claim 19, wherein:said latch arm includes a first spring retainer, said swing arm possesses a second spring retainer, a first end of a spring is coupled to said first spring retainer, and a second end of said spring is coupled to said second spring retainer.
  • 24. A self-cleaning oven, comprising:a motor operable to rotate a drive shaft in response to said oven being placed in a self-cleaning mode of operation; a latch mechanism movable between an unlatched position and a latched position in response to rotation of said drive shaft, said latch mechanism including: a latch housing; a drive link having (i) a first end portion mechanically coupled to said drive shaft whereby rotation of said drive shaft causes movement of said drive link, and (ii) a second end portion; a first link arm having (i) a first end portion pivotally coupled to said latch housing, and (ii) a second end portion pivotally coupled to said second end portion of said drive link; a second link arm having (i) a first end portion, and (ii) a second end portion pivotally coupled to said second end portion of said drive link; and a latch arm having (i) a first end portion having a locking contact portion, and (ii) a second end portion pivotally coupled to said first end portion of said second link arm.
  • 25. The self-cleaning oven of claim 24, wherein said locking contact portion of said latch arm includes a hook.
  • 26. The self-cleaning oven of claim 24, further comprising an oven door having a lock bar, wherein:said locking contact portion of said latch arm is spaced apart from said lock bar of said door when said latch mechanism is located in said unlatched position, and said locking contact portion of said latch arm is positioned in contact with said lock bar of said door when said latch mechanism is located in said latched position.
  • 27. The self-cleaning oven of claim 24, wherein 180° of rotation of said drive shaft causes said latch mechanism to be moved from said unlatched position to said latched position.
  • 28. The self-cleaning oven of claim 24, wherein said latch mechanism further includes a swing arm having (i) a first end portion pivotally coupled to said latch housing, and (ii) a second end portion pivotally coupled to said first end portion of said second link arm.
  • 29. The self-cleaning oven of claim 28, further comprising a spring coupled to bias an intermediate portion of said latch arm toward an intermediate portion of said swing arm.
US Referenced Citations (23)
Number Name Date Kind
1573866 Rogers Feb 1926 A
3438666 Erickson Apr 1969 A
3476424 Erickson Nov 1969 A
3610883 Holtkamp et al. Oct 1971 A
3831580 McLean Aug 1974 A
3912904 Phifer Oct 1975 A
3958822 Germer May 1976 A
4013312 DeWeese Mar 1977 A
4082078 Thuleen et al. Apr 1978 A
4133337 Shea Jan 1979 A
4163443 Peterson Aug 1979 A
4364589 Watson Dec 1982 A
4554907 Overley et al. Nov 1985 A
4838586 Henne Jun 1989 A
4862870 Fox Sep 1989 A
4927996 Genbauffe May 1990 A
5029910 Genbauffe et al. Jul 1991 A
5220153 Malone et al. Jun 1993 A
5413390 Filippi May 1995 A
5419305 Hanley May 1995 A
5440103 Martin Aug 1995 A
5477030 Buckshaw et al. Dec 1995 A
5493099 McWilliams, III Feb 1996 A