AU2019256071A1

AU2019256071A1 - Latch module, method for controlling latch module, and cooking apparatus to which same is applied

Info

Publication number: AU2019256071A1
Application number: AU2019256071A
Authority: AU
Inventors: Seongho Jeong; Jeongkil Kim; Sangki Lee; Jangmo SHIN; Myeong Jun Shin
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2018-04-16
Filing date: 2019-03-13
Publication date: 2020-11-12
Anticipated expiration: 2039-03-13
Also published as: WO2019203444A1; AU2019256071B2; CN112041524A; CN112041524B

Abstract

The present invention relates to a latch module in which an automatic opening function and a locking function are integrated, a method for controlling same, and a cooking apparatus to which same is applied. The positions to which a latch (50) of the latch module is movable may comprise a first basic position, a second basic position, and a third basic position. The first basic position and the third basic position may be positions where the latch (50) is engaged with a catch structure (22), so that a door (20) is maintained in a closed state. The second basic position may be a position where the latch (50) is not engaged with the catch structure (22). The latch may be moved to any one of the three positions by a controller. In a position where the door (20) is closed, a hinge module may apply force to the door (20) in an opening direction. Accordingly, when the latch (50) is in the second basic position, the door (20) may be opened by the force of the hinge module.

Description

LATCH MODULE, METHOD FOR CONTROLLING LATCH MODULE, AND COOKING APPARATUS TO WHICH SAME IS APPLIED FIELD OF THE DISCLOSURE

[001] The present disclosure relates to a latch module having an automatic

opening function and a secure lock function incorporated therewith, a

method of controlling such latch module, and a cooking device applying

such latch module.

BACKGROUND

[002] A cooking device such as an oven or a microwave oven includes a

rectangular parallelepiped appearance. The cooking device includes an

inner cooking chamber having an open front thereof, and a door in front of

the cooking chamber.

[003] The door may be opened in various ways. For example, a hinge-connected

door connected by a hinge method rotates about a rotational shaft. The

hinge type door may have a handle or groove that the user may grip.

[004] A cooking device may have an automatic opening function of a door

thereof to improve the quality of use. Of course, even if the automatic

opening function of the door is applied, for convenience of the user, the

door may be designed to be manually opened or closed.

[005] Further, a self-cleaning function is added to the cooking device so that the

89932573.1 cooking chamber is easily cleaned. The self-cleaning function enables heating the inside of the cooking chamber to a high temperature so that food attached to an inner wall of the cooking chamber is burned, or treating the food attached to the inner wall of the cooking chamber with high temperature steam, so that the food is softened and conveniently removed during cleaning. In order to prevent a safety accident, the door of the cooking device may be securely closed during a self-cleaning operation.

[006] US Patent No. 7,726,294 and US Patent Publication No. 2007/0296224

disclose an operating structure of a hook for maintaining a door in a

securely closed state during the self-cleaning operation. By rotating a drive

such as a motor and the like, and applying a link structure, when the door

needs to be maintained in a securely closed state, the hook is operated by

the drive so that the hook is engaged with the door, and when the door no

longer needs to be maintained in the securely closed state, the hook is

operated again by the drive so that the hook is released from the door.

[007] With the operating structure of a hook described above, after the hook is

released from the door, a door lock device enables closing the door and

does not enable automatically opening the door. That is, the door lock

device has no means for automatically opening the door.

[008] A secure (secure lock, self-cleaning lock) device that serves to securely

lock the door during the self-cleaning operation and an automatic opening

(auto door open) device that serves to automatically open the door may be

89932573.1 applied individually. That is, US Patent No. 7,726,294 and US Patent

Publication No. 2007/0296224 provide a drive (a motor) that provides

power and a power transmission structure to securely lock the door, and

another drive (another motor) that provides power and another power

transmission structure to automatically open the door.

[009] It is not easy to incorporate a secure lock function of a door for self

cleaning with a separate automatic opening function of the door when a

manual opening and closing function of the door needs to be implemented

as well.

[010] However, when new functions are added, the modules for implementing

the functions are added individually, thereby increasing the number of

components and production costs, as well as increasing the occupied

volume in the cooking device, thereby decreasing the volume of the

cooking chamber.

[011] It is desirable to have a module incorporated with various functions.

However, in situations described above, when the module is incorporated

with a safety function for preventing accidents, the function for preventing

the accidents needs to be robust and reliable.

[012] Accordingly, a door control module capable of incorporating all functions

as well as minimizing the number of parts, and having a safety function for

preventing an accident is highly desirable.

[013] On the other hand, when the door control module is incorporated with

89932573.1 various functions, the drive control also becomes complicated, and more switches for controlling the parts that drive the door control module may need to be installed. However, an increase in the number of installed switches not only increases an occupied volume in the door control module, but also raises production costs.

[014] Further, when the functions are incorporated, initializing the door control

module is required when the cooking device is initially supplied with power.

However, if the door control module does not have a proper initialization

structure and operated, for example, the door may accidentally open

automatically during initialization of the door control module, and the user

may think that the cooking device is operating incorrectly or the cooking

device has failed. Therefore, the door control module should not

automatically open the door when the door control module is initialized.

[015] There are prior art documents such as US Patent No. 7,726,294 (patent

document 1) and US Patent Publication No. 2007/0296224 (patent

document 2).

SUMMARY

Technical Subject

[016] The present disclosure solves the above-mentioned problems. The present

disclosure provides a latch module that implements a manual lock function

of a door and a secure lock function of a door for self-cleaning operation

of a cooking chamber with one latch and a cooking device applying such

89932573.1 latch module.

[017] The present disclosure further provides a latch module that implements a

manually opening and closing function of a door and an automatic opening

function of a door and a secure lock function of a door by operating with

one latch and a cooking device applying such latch module.

[018] The present disclosure also provides a latch module that implements a

manually opening and closing function of a door and an automatic opening

function of a door and a secure lock function of the door by operating with

one latch with one drive source and one power transmission structure, and

a cooking device applying such latch module.

[019] The present disclosure also provides a latch module that implements a

secure lock and unlock function of a door by means of a kinematic

interference between the two components while one latch implements the

two functions and a cooking device applying such latch module.

[020] The present disclosure also provides a structure capable of accurately

controlling a latch module while minimizing the number of switches to be

installed, a method of controlling such latch module, and a cooking device

applying such latch module.

[021] The present disclosure also provides a structure of a latch module in which

a user may not mistakenly consider the operation of the cooking device as

malfunctioning or failure at the beginning of the driving of the cooking

device and a method of controlling such latch module.

89932573.1

Technical Solution

[022] The present disclosure may be applied to an appliance such as a cooking

device including a main body 10 having a cooking chamber (a cavity), a

door 20 that opens and closes an open front of the cooking chamber, and

an opening or closing rotational shaft 314 as a center of rotation of opening

and closing a movement of the door.

[023] The opening and closing rotational shaft 314 rotatably connects the door

20 with respect to the main body about a horizontal rotational shaft

extending in a left-right direction and disposed at a front lower portion of

the main body 10. Accordingly, the door may have a pull-down structure

in which the door is rotated forward about the rotational shaft and descends

and is opened.

[024] The door may be connected to the main body via a hinge module 300

including the opening and closing rotational shaft 314. The hinge module

300 may apply an elastic force so as to move the door in an opening

direction od (see FIGS. 1 and 10) in a range of initial opening angle (0 to

al) and may apply an elastic force the door in a closing direction thereof

cd (see FIGS. 1 and 12) in a range (al to a3) in which an opening angle of

the door exceeds the initial opening angle al.

[025] The door may be opened by its own weight at the initial opening angle al.

A damper 350 starts to damp an opening speed of the door at a damping

beginning angle a2 greater than the initial opening angle al. The opening

89932573.1 speed is controlled until the door is opened to a completely opened angle a3 so that the door is opened slowly.

[026] The cooking device may have a self-cleaning function of raising a

temperature inside of the cooking chamber to a high temperature.

Accordingly, the door is prevented from being opened in advance when the

door is securely locked to perform the self-cleaning function.

[027] The cooking device may further apply a structure that automatically opens

the door by means of command input by a user. Generally, the door also

may be manually opened and closed.

[028] According to the present disclosure, all of these functions are implemented

by one latch module 4. The latch module 4 may be installed on the main

body 10 and a rear upper portion of the door 20 may have a pin 22 which

is an engaged structure that is engaged with or released from a latch 50 of

the latch module 4.

[029] The position at which the latch 50 may move may include a first basic

position, a second basic position, and a third basic position.

[030] Each of the first basic position and the third basic position may be a

position in which the latch 50 is engaged with the engaging structure 22 so

as to maintain a state in which the door 20 is closed.

[031] The second basic position may be a position in which the latch 50 is not

engaged with the engaging structure 22.

89932573.1

[032] The first basic position may be a position in which, when an external force

is applied to the door 20 in a direction of opening the door 20, the latch 50

is released from the engaging structure 22 so that the door is opened, while

the third basic position may be a position in which, even if the external

force is applied to the door 20 in a direction of opening the door 20, a state

in which the latch 50 is engaged with the engaging structure 22 is

maintained.

[033] The latch may be moved to at least one position of the three positions by

the controller. In other words, the controller may control the position of the

latch.

[034] The hinge module may apply a force in a direction of opening the door 20

at a position in which the door 20 is closed. Thus, when the latch 50 is in

the second basic position, the door 20 may be opened by the force of the

hinge module.

[035] In order to solve the above-described problems, according to the present

disclosure, the latch module 4 may include a bracket 40 as a base of the

latch module; a latch 50 installed in the bracket 40 rotatably (a rotational

movement) about a pivot shaft 54 and having a hook 51 engaged with the

pin 22, an elastic body 90 that moves the latch 50 to rotate in a first

direction; a drive 60 that provides a power for rotating the latch 50 in a

second direction which is an opposite to the first direction using a force

greater than an elastic force of the elastic body; and a power transmission

89932573.1

70 that transmits the power of the drive 60 to the latch 50.

[036] The hook is opened toward the first direction, and an engaging surface 52

that is engaged with the pin is provided inside of the hook. An inclined

insertion surface 53 may be provided on a surface opposed to the engaging

surface 52 of the hook.

[037] The engaging surface 52 includes a disengaged inclined surface 521

arranged closer to the first direction and a secure lock surface 522 arranged

closer to the second direction. The two surfaces 521 and 522 are connected

to each other via a soft curved surface so that a sliding of a pin about the

two surfaces is smooth.

[038] Depending on a rotation position of the latch 50, the portions of the

engaging surface 52 in contact with the pin are varied. The pin 22 contacts

the disengaged inclined surface 521 or contacts the secure lock surface 522

depending on the rotation position of the latch 50.

[039] In a general state, that is, in a manual lock state where the user may

manually open and close the door, a rear surface of the pin of the door

contacts the disengaged inclined surface 521 when the door is closed. In

order to allow the user to manually open the door, when the latch is rotated

so as to be in a state in which the disengaged inclined surface 521 contacts

the pin 22, the disengaged inclined surface 521 has a surface inclined in the

opening direction of the door toward the first direction. When the user pulls

the door in an opening direction thereof, the latch 50 may rotate in the

89932573.1 second direction by using a force in which the pin pushes the disengaged inclined surface, which is greater than the elastic force, and thereby the door may be manually opened.

[040] When the user closes the door in a state where the door is opened, the

surface of the pin of the door contacts the inclined insertion surface 53. In

order for the user to manually close the door, when the latch rotates so as

to be in the state in which the inclined insertion surface 53 contacts the pin

22, the inclined insertion surface 53 has a surface inclined in the closing

direction of the door toward the first direction.

[041] The inclined insertion surface 53 may be provided not only in a position

range opposed to the disengaged inclined surface 521 but also in a position

range opposed to the secure lock surface 522. It is possible to close the

opened door regardless of whether the latch is in any position (the manual

lock position and the secure lock position).

[042] In a general state, the elastic body is involved in the operation of the latch

for a manual opening and closing operation.

[043] In a completely locked state where the user does not manually open the

door for self-cleaning and the like, that is, in the secure lock state, the pin

of the door contacts the secure lock surface 522. The latch 50 is further

rotated in the first direction than in the manual lock state and the pin of the

door is relatively positioned deeply inward the hook (actually, the pin

remains its position and the hook is further rotated).

89932573.1

[044] In order for the hook to completely securely lock the door, the secure lock

surface 522 may have a surface inclined in the closing direction of the door

toward the first direction. Then, when the user pulls the door, a force

applied by the pin of the door to the hook further rotates the hook in the

first direction. That is, the more the user opens the door, the deeper the pin

is positioned deeply inward the hook. In other words, the more the user

opens the door, the more the hook securely locks the pin.

[045] Similar result is obtained if the secure look surface 522 has a surface

perpendicular to the opening direction of the door. That is, even if the user

opens the door, such force does not lead to the rotation of the latch.

[046] An elasticity of the elastic body contributes to rotate the latch from a

manual lock position to a secure lock position.

[047] As described above, according to the present disclosure, the engaging

surface 52 of the hook of the latch for opening and closing the door has a

portion capable of manually opening and closing the door and a complete

secure lock portion. It is possible to determine which one of the two

portions contacts the pin of the door depending on a rotation displacement

of the latch so that both the manual lock state and the secure lock state of

the door may be implemented by one latch.

[048] The automatic opening operation of the door and the secure lock operation

of the door may be implemented with one latch, one drive and power

transmission that drive the latch.

89932573.1

[049] The power transmission is a cam 70 in contact with a contact surface 55

provided on the side of the latch 50. A center of rotation 711 of the cam 70

may be disposed in adjacent to a first direction, than a side of the latch 50

to which the cam contacts. It is possible to determine a position of the latch

by changing the radius of the cam that contacts the latch 50 depending on

the rotational displacement of the cam.

[050] As the elastic body elastically supports the latch so as to rotate in the first

direction and the center of rotation 711 of the cam 70 is disposed in adjacent

to the first direction than the latch, a degree in which the latch may move

in the first direction may be determined depending on the radius of the cam

that contacts the latch. Of course, even in this state, the latch may move in

the second direction by a force greater than the elastic force of the elastic

body. When the force greater than the elastic force of the elastic body

disappears, the latch is rotated and returned again by the elastic body to the

position in contact with the cam in the first direction.

[051] A combination of the elastic body 90 that elastically forces the latch in the

first direction and the cam 70 disposed in adjacent to the first direction than

the latch may simply enable a basic position of the latch to be adjusted by

adjusting a radius of the cam in contact with the latch. Adjusting the basic

positions of the latch may be a method of determining which one of the

disengaged inclined surface 521 and the secure lock surface 522 in the

engaged surface 52 of the hook 51 of the latch contacts the pin 22 of the

89932573.1 door.

[052] The cam 70 may include the radiuses 731, 732, and 733 having at least

three different radiuses in a circumferential direction thereof at the outer

circumference thereof. The first radius 731 enables the latch to be in the

first basic position and the second radius 732 enables the latch to be in the

second basic position, and the third radius 733 enables the latch to be in the

third basic position.

[053] When the latch is moved in a second direction w2 in the first basic position,

the latch may reach the second basic position. When the latch is moved in

a first direction w Iin thefirst basic position, the latch may reach the third

basic position.

[054] The first radius 731 as a reference enables a latch 50 to be in a general basic

position, that is, a position where the user may manually open and close

the door (a manual lock position). The pin of the door contacts the

disengaged inclined surface 521 of the hook 51 of the latch 50 at a position

where the first radius 731 contacts the contact surface of the latch 50.

[055] The second radius 732 has a radius greater than the first radius 731. The

second radius is connected to the first radius via a connecting surface 734

having a smooth curved surface. Therefore, when the cam rotates in a first

rotational direction c Isuch that a contact portion of the cam and the latch

is moved from the first radius to the second radius, a basic position of the

latch 50 further moves in the second direction w2. When the second radius

89932573.1 contacts the latch, the hook of the latch moves to the open position and may no longer be engaged with the pin 22 of the door. That is, the pin is relatively away from the hook.

[056] Accordingly, when the latch in contact with the first radius contacts the

second radius as the cam rotates, the door is moved by the elastic force by

the hinge module 300 so that the door is opened to the initial opening angle

al and the door is completely opened by the weight of the door itself.

[057] The third radius 733 has a radius less than the first radius 731. The third

radius is connected to the first radius via a connection surface 734 having

the smooth curved surface. Therefore, when the cam rotates in a second

rotational direction (c2; a direction opposite to the first rotational direction)

so that the contact portion of the cam the latch is moved from the first radius

to the third radius, the basic position of the latch is further moved in the

first direction w Ito move to the secure lock position. When the third radius

contacts the latch, the hook is engaged with the pin of the door deeply

inward. That is, the pin of the door contacts the secure lock surface 522 of

the hook 51 of the latch 50.

[058] According to the present disclosure, the operation of moving the latch 50

from the first basic position to the third basic position may be made by the

elastic body 90. However, if the latch 50 is engaged with the first basic

position due to an unexpected state, the elastic force applied by the elastic

body 90 in the first direction wl may not enable the latch 50 to move from

89932573.1 the first basic position to the third basic position.

[059] According to the present disclosure, while the cam rotates from the first

mode to the third mode, the surface of the cam and the latch are

kinematically interfered with each other, and power of the drive is

transmitted to the latch so as be applied in a direction of moving from the

first basic position to the third basic position.

[060] Further, due to the kinematic interference of the cam and the latch when

the cam is in a third mode and the latch is also in the third basic position,

the present disclosure provides a structure in which the latch is prevented

from deviating from the third basic position toward thefirst basic position.

[061] To this end, according to the present disclosure, the latch 50 further

provides an extension 58 that may be kinematically interfered with the cam.

The extension 58 has an sub-contact surface 59 that approaches the surface

of the cam 70 as the latch 50 moves in thefirst direction and is away from

the surface of the cam 70 as the latch 50 moves in the second direction.

[062] In the first mode where the first radius 731 of the cam contacts the contact

surface 55 of the latch 50 so that the latch is in thefirst basic position (the

manual lock state), the extension 58 may not disturb the manual opening

and closing rotation of the latch 50.

[063] To this end, the cam surface that faces the sub-contact surface 59 when the

cam is in the first mode may have a radius rM1 so that a movement for the

sub-contact surface 59 to approach the cam surface is allowed even if the

89932573.1 latch 50 is moved from the first basic position to the second basic position.

[064] In other words, a distance dmp between a position mp of the sub-contact

surface 59 and a center of rotation 711 of the cam 70 while the cam is in

the first mode and the latch 50 is in the first basic position may be greater

than a radius rM1 of the cam surface in contact with the sub-contact surface

59 when the first radius 731 of the cam contacts the contact surface 55 of

the latch 50. A distance dop between a position op of the sub-contact

surface 59 and the center of rotation 711 of the cam 70 while the cam is in

the first mode and the latch 50 is in the second basic position may be equal

to or greater than a radius rM1 of the cam surface that faces the sub-contact

surface 59 while the first radius 731 of the cam contacts the contact surface

55 of the latch 55.

[065] In the first mode where the first radius 731 of the cam contacts the contact

surface 55 of the latch 50, the cam surface that faces the sub-contact surface

59 may be the first radius 731, the third radius 733 or the connecting surface

734 that connects the first radius 731 and the third radius 733.

[066] In order for the latch to be moved by the cam from the first basic position

to the second basic position (the automatic opening position), when the cam

rotates in the first rotational direction c I from the position when the cam is

in the first mode to the position when the cam is in the second mode, the

extension 58 moves in the direction of approaching the cam. In this step,

the extension 58 may not contact the cam or may not be interfered with the

89932573.1 cam.

[067] While a contact point of the cam and the contact surface 55 of the latch 50

is moved from the first radius to the second radius 732 as the cam rotates,

the sub-contact surface 59 is not interfered with the surface of the cam 70.

[068] In a second state where the second radius 732 of the cam contacts the

contact surface 55 of the latch 50, the sub-contact surface 59 may face the

first radius 731 of the cam 70 and the sub-contact surface 59 may not

contact the surface of the cam 70.

[069] A distance dop between a position op of the sub-contact surface 59 and the

center of rotation 711 of the cam 70 while the latch 50 is in the second basic

position may be equal to or greater than a radius rM2 of the cam surface

that faces the sub-contact surface 59 while the second radius 732 of the

cam contacts the contact surface 55 of the latch 50.

[070] In order for the latch to be moved from the first basic position to the third

basic position (the secure lock position), while the cam rotates in the

second rotational direction c2 from the position when the cam is in the first

mode to the position when the cam is in the third mode, when the latch is

not smoothly moved in the first direction wl in spite of a force of applying

the elasticity of the elastic body 90, the cam may force the latch to move to

the first direction wl by interfering the cam with the extension 58 of the

latch.

[071] To this end, while the contact point of the cam and the contact surface 55

89932573.1 of the latch 50 is moved from the first radius 731 to the third radius 733 as the cam rotates, the radius of the surface of the cam 70 that faces the sub contact surface 59 may be set to exceed the distance dmp between the position mp of the sub-contact surface 59 and the center of rotation 711 of the cam 70 when the latch 50 is in the first basic position.

[072] The radius rM3 of the cam surface that faces the sub-contact surface 59

when the third radius 733 of the cam contacts the contact surface 55 of the

latch 50 may be greater than the distance dmp between the position mp of

the sub-contact surface 59 and the center of rotation 711 of the cam 70

when the latch 50 is in the first basic position.

[073] Even if the latch 50 is stopped, the cam may forcedly push the latch 50 to

move the latch.

[074] The cam surface that faces the sub-contact surface 59 may be the second

radius 732 when the third radius 733 of the cam contacts the contact surface

55 of the latch 50.

[075] The radius rM3 of the cam surface that faces the sub-contact surface 59

when the third radius 703 of the cam contacts the contact surface 55 of the

latch 50 may be substantially equal to the distance dlp between the position

lp of the sub-contact surface 59 and the center of rotation 711 of the cam

70 when the latch 50 is in the third basic position, then the latch is

fundamentally prevented from being rotated in the second direction w2 by

an unexpected external force when the latch is in the secure lock position

89932573.1 due to the interference between the sub-contact surface 59 and the cam.

[076] If the latch position adjusting profile 73 of the cam may be designed so that

the second radius is disposed at one side of the first radius 731 (a contact

surface for manual lock) and the third radius is disposed at the other side

of the first radius and the cam may be rotated in one direction or rotated in

the other direction, the position of the latch may be simply adjusted. In

order to implement the adjustment of the position of the latch more simply,

the drive may be a motor 60 rotatable in both directions. More simply, the

cam may be directly connected to a rotational shaft 61 of the motor.

[077] According to the present disclosure, both the operations of the automatic

opening and the complete secure lock of the door are implemented with

one latch, which is determined by the basic position of the latch. The basic

position of the latch may be determined by the cam and the cam may be

controlled by a controller.

[078] If the cam is only rotatable in one direction, the latch may contact the cam

in an order of the first radius -- the second radius -- the third radius -- the

first radius, or in an order of the first radius -- the third radius-- the second

radius -- the first radius.

[079] If the latch contacts the cam in the order of the first radius-- the second

radius -- the third radius -- the first radius, the door may be automatically

opened before the secure lock of the door, it would be difficult to

implement the secure lock function of the door. On the other hand, if the

89932573.1 latch contacts the cam in the order of the first radius -- the third radius- the second radius -- the first radius, the door may be opened by automatic opening after carrying out the secure lock function of the door. Therefore, if the motor rotatable in one direction only is used, the latch is installed such that the motor rotates in a direction in which the latch may contact the cam in the order of the first radius -- the third radius -- the second radius

-- the first radius.

[080] The rotational displacement of the cam may be controlled by pressing or

releasing the switches 81 and 82 installed around the cam as the cam rotates.

When the button of the switch is pressed, the switch may be turned on.

When the button of the switch is released, the switch may be turned off.

[081] Basically, in order to determine a rotational displacement of the cam based

on the three basic positions of the latch (the manual lock position as the

position of the latch in a state in which the first radius of the cam contacts

the contact surface of the latch, the opening position as the position of the

latch in a state in which the second radius of the cam contacts the contact

surface of the latch, and the secure lock position as the position of the latch

in a state in which the third radius of the cam contacts the contact surface

of the latch), three switches may be installed in the positions, respectively,

and a pressing boss that presses the switch may be provided in the cam.

The first radius contacts the latch when the first switch is pressed and the

second radius contacts the latch when the second switch is pressed and the

89932573.1 third radius contacts the latch when the third switch is pressed. Then, the basic position of the latch may be adjusted through a control that the motor continues to rotate while no switch is pressed, and the rotation is stopped when the switch is pressed.

[082] It is also possible to control the three basic positions of the latch by using

the two switches. The latch module may further include a first switch 81

and a second switch 82 installed at the bracket 40.

[083] The cam 70 may implement a first mode in which both the first switch 81

and the second switch 82 are pressed, a second mode in which the first

switch 81 is pressed and the second switch 82 is not pressed, the third mode

in which the second switch 82 is pressed and the first switch is not pressed,

and the fourth mode in which both the first switch 81 and the second switch

82 are not pressed depending on a rotation position of the cam.

[084] The cam 70 may further include a switch pressing profile 72 capable of

implementing the four modes, separate from the latch position adjusting

profile 73. In other words, the cam 70 may include the latch position

adjusting profile 73 and the switch pressing profile 72 and the latch position

adjusting profile 73 and the switch pressing profile 72 may be provided

separately.

[085] When the cam 70 is rotated so that any one mode (first selected mode) of

the first to fourth modes is implemented by the switch pressing profile 72,

the first radius 731 may contact the latch 50. When the cam 70 is rotated

89932573.1 so that the switch pressing profile 72 is in another mode (second selected mode) of the first to fourth modes, the second raids 732 may contact the latch 50. When the cam 70 is rotated so that the switch press profile 72 is in yet another mode (third selected mode) of the first to fourth modes, the third radius 733 may contact the latch 50. The other mode of the first to fourth modes may be the fourth selected mode. The first selected mode may be the first mode, the second selected mode may be the second mode, the third selected mode may be the third mode, and the fourth selected mode may be the fourth mode.

[086] The first switch 81 and the second switch 82 may be disposed at

substantially the same distance from the center of rotation 711 of the cam

70. The switch pressing profile 72 may include a first pressing boss 711

that presses the first switch 81 or the second switch 92 or does not press

both the first switch 81 and the second switch 82 depending on the rotation

position of the cam, and a second pressing boss 722 that presses the first

switch 81 or the second switch 82 or does not press both the first switch 81

and the second switch 82 depending on the rotation position of the cam.

[087] The cam may be in a range in the first mode in which the first pressing boss

721 and the second pressing boss 722 press the first switch 81 and the

second switch 82 at the same time, respectively, or a range in the second

mode in which the second pressing boss 722 presses the first switch 81 and

the first pressing boss 721 does not press the second switch 82, and a range

89932573.1 in the third mode in which the first pressing boss 721 presses the second switch 82 and the second pressing boss 722 does not press the first switch

721, and a range in the fourth mode in which the first pressing boss 721

and the second pressing boss 722 do not both the first switch 81 and the

second switch 82 depending on the rotation angle thereof.

[088] The button 811 of the first switch 81 and the button 821 of the second

switch 82 have a predetermined angle b with respect to the center of

rotation 711 of the cam. The first pressing boss 721 and the second pressing

boss 722 may also have a predetermined angle b with respect to the center

of rotation 711 of the cam. The angle b may be less than 1800 such that the

two switches 81 and 82 are not arranged on the same straight line passing

through the center of rotation 711 of the cam and the two pressing bosses

721 and 722 are not arranged on the same straight line passing through the

center of rotation 711 of the cam. Preferably, the angle may be 90 or more

or less than 1800 or may have an obtuse angle. More preferably, the angle

may be about 120°.

[089] In the rotation range (the range in the first mode) of the cam where both

the first switch and the second switch are pressed, the first radius 731 may

contact the latch 50. In the rotation range (the range in the second mode)

of the cam in which the first switch is pressed and the second switch is not

89932573.1 pressed, the second radius 732 may contact the latch 50. In the rotation range (the range in the third mode) of the cam in which the first switch is not pressed and the second switch is pressed, the third radius 733 may contact the latch.

[090] The latch module may be controlled by a controller controlling the

operation of automatically opening the door, controlling the operation of

securely locking the door, and controlling the operation of securely

unlocking the door.

[091] Controlling the operation of automatically opening the door is performed

by rotating the cam 70 in the first rotational direction c I in the first selected

mode of the above modes to change the cam 70 to the second selected mode

so as to stop the rotation of the cam 70, and by rotating the cam 70 in the

second rotational direction c2 which is an opposite direction of the first

rotational direction c Iin the second selected mode to return the cam 70 to

the first selected mode so as to stop the rotation of the cam 70.

[092] Controlling the operation of securely locking the door is performed by

rotating the cam 70 in the second rotational direction c2 in the first selected

mode to change the cam 70 in the third selected mode to stop the rotation

of the cam 70, so that the door is securely locked, thereby preventing the

door being manually opened by the user.

[093] Controlling the operation of releasing the door from the securely locked

state is performed by rotating the cam 70 in the first rotational direction cl

89932573.1 in the third selected mode to change the cam 70 in thefirst selected mode so as to stop the rotation of the cam 70, so that the door is returned to the state where the secure lock of the door is released and the door is manually opened and closed.

[094] According to the present disclosure, a method of controlling the latch

module further includes a position search and a sequence of an

initialization control of the cam of the latch module. The search and

initialization control may be executed when the cam is in the fourth

selected mode in the initial drive of the latch module.

[095] First, the cam 70 is rotated in the second rotational direction c2. According

to the present disclosure, when the initial search drive step of rotating the

cam 70 in the second direction is performed in the fourth mode, an error

that the door is opened may not occur. Specifically, after the initial search

drive step, the cam is changed from the fourth selected mode (the fourth

mode) to the first selected mode (the first mode) or to the third selected

mode (the third mode).

[096] When the cam is changed from the fourth selected mode (the fourth mode)

to the first selected mode (the first mode), the drive of the cam is terminated.

[097] When the cam is changed from the fourth selected mode (the fourth mode)

to the third selected mode (the third mode), the cam is rotated in the first

rotational direction cl. Then, the cam 70 is changed to the first selected

mode (the first mode) via the fourth selected mode (the fourth mode). When

89932573.1 the first mode is thus set, the drive of the cam is terminated.

[098] While the user uses the cooking device, the cam may not be in the second

selected mode (the second mode) during the initial search drive step.

However, just after manufacturing the product, the cam may be in the

second mode during the initial search drive step, forjust one chance. In this

case, during the initial search drive step, after the cam is changed to the

second selected mode, the cam 70 is further rotated in the second rotational

direction c2, and the cam 70 is changed to the first selected mode (the first

mode), the drive of the cam 70 may be terminated.

[099] The present disclosure further provides a cooking device to which the latch

module and the method of controlling such latch module are applied.

Further, the present disclosure may be applied not only to the cooking

device, but also to an appliance including a main body having a cavity and

a door that opens and closes such main body.

Effect of the Disclosure

[100] According to the present disclosure, a structure of the latch module applied

to a cooking device may implement a manual lock function of the door and

a secure lock function of a door for an operation of self-cleaning by one

latch.

[101] Further, according to the present disclosure, the structure of the latch

module may implement an automatic opening function of a door and a

secure lock function of a door while one latch, one drive, and one power

89932573.1 transmission are applied.

[102] Further, according to the present disclosure, in the structure of the latch

module, it is possible to manually open and close the door by an elastic

body, and also to perform a secure lock of the door by the elastic body. In

addition, an interference structure of the latch and the cam complements a

secure lock function of the elastic body. Therefore, even if abnormality

occurs during operation of the elastic body, an operation of securely

locking the door may be made by the cam.

[103] Further, according to the present disclosure, the structure of the latch

module may prevent the latch in the secure lock state from being released

by an unexpected external force due to the interference between the cam

and the latch. Therefore, all operations may be implemented by one latch

and one cam.

[104] Further, according to the present disclosure, in the structure of the latch

module, the automatic opening of the door and secure lock of the door may

be controlled through the two switches and a simple control.

[105] Further, according to the present disclosure, a method of controlling the

latch module may only perform the initial position search of the cam and

the latch with a simple control algorithm and the door may not be opened

unintentionally in the initial search step.

[106] Specific effects of the present disclosure, with the above-described effect

will be described in conjunction with the described specific details for

89932573.1 carrying out the disclosure below.

BRIEF DESCRIPTION OF THE DRAWINGS

[107] FIG. 1 is a side view of a cooking device including a latch module

according to an embodiment of the invention.

[108] FIG. 2 is a transparent perspective view of a hinge module that connects a

door and a main body of a cooking device according to an embodiment of

the invention.

[109] FIG. 3 is a side view of FIG. 2.

[110] FIG. 4 is a perspective view of a latch module according to an embodiment

of the invention.

[111] FIG. 5 is an exploded perspective view of the latch module of FIG. 4.

[112] FIG. 6 is a top view of a latch of the latch module of FIG. 4.

[113] FIG. 7 is a plan view of a cam of the latch module of FIG. 4.

[114] FIG. 8 is a graph of a radius of the cam depending on an angular position

of the cam of FIG. 7.

[115] FIG. 9(a) is a bottom view of a cooking device having the latch module of

FIG. 4, and FIG. 9(b) is a plan view of the cam and a part of the latch in

contact with the cam, both representing a state where the latch is engaged

with a pin of a door while the latch is in a manual lock position.

[116] FIG. 10(a) is the bottom view of the cooking device, and FIG. 10(b) is the

89932573.1 plan view of the cam and the part of the latch in contact with the cam, both representing a state where the latch module is operated and the latch moves to the open position.

[117] FIG. 11(a) is the bottom view of the cooking device, and FIG. 11(b) is the

plan view of the cam and the part of the latch in contact with the cam, both

representing a state where the latch is disengaged from the pin of the door

and the door is opened to an initial open angle.

[118] FIG. 12(a) is the bottom view of the cooking device, and FIG. 12(b) is the

plan view of the cam and the part of the latch in contact with the cam, both

representing a state where the latch module operates and the latch is in the

manual lock position while the latch is disengaged from the pin of the door.

[119] FIG. 13(a) is the bottom view of the cooking device, and FIG. 13(b) is the

plan view of the cam, both representing a state where the latch module

operates and the latch is moved to the secure lock position.

[120] FIG. 14 is a graph showing a range of the cam in contact with a contact

surface of the latch, a contact position of the cam in contact with the contact

surface of the latch, a movement of the contact position of the cam in

contact with the contact surface of the latch, and a position in which the

cam presses a switch together, in addition to FIG. 8.

[121] FIG. 15 shows a first case in which the cam is in a fourth mode.

[122] FIG. 16 shows a second case in which the cam is in the fourth mode.

89932573.1

[123] FIG. 17 shows a third case in which the cam is in the fourth mode.

[124] FIG. 18 is a schematic view of an algorithm for searching and setting an

initial position of the cam.

[125] FIG. 19 shows a control system including a controller.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[126] Hereinafter, the present disclosure will describe in detail embodiments of

the invention with reference to the accompanying drawings.

[127] The present disclosure may be implemented in many different manners and

is not limited to the embodiments set forth herein. Certain features of the

embodiments may be omitted and features of one embodiment may be

combined with features of another embodiment. The embodiments are

provided so that this disclosure will be thorough and complete, and will

enable those skilled in the art to make and use of the invention.

[128] [Overall structure of cooking device]

[129] Hereinafter, according to an embodiment, an overall structure of a cooking

device to which a method of automatically opening a door is applied will

be described. However, it should be noted that the embodiments are not

limited to a cooking device. The embodiments may be applied to all

appliances having a pull-down door. An appliance may be that used in a

home or commercially.

[130] Referring to FIG. 1, according to an embodiment of the invention, an oven

89932573.1 as a cooking device will be described as an example of an appliance.

According to the present disclosure, the appliance is not limited to a

cooking device and a cooking device is not limited to an oven.

[131] The cooking device includes a main body 10 having a substantially

rectangular parallelepiped shape, an open front, and a cavity, and a door 20

installed at a front of the main body 10 that can cover the cavity.

[132] The main body 10 includes an outer housing (not shown in FIG. 1 to show

an inner structure of the main body) that defines an outer appearance of the

cooking device and an inner housing 11 installed in the outer housing. The

inner housing may be provided with the cavity opened forward. The cavity

forms a cooking chamber. In an upper portion, a lower portion, a rear

portion, and side portion of the main body 10, various components needed

for operation of the cooking appliance may be provided.

[133] The door 20 has a pull-down opening and closing structure about a

horizontal hinge shaft 314 disposed at a lower end of the door. In other

words, the door 20 is rotated forward and downward with respect to the

main body to be opened and is rotated rearward and upward with respect

to the main body to be closed.

[134] As shown in FIG. 1, the door 20 may open or close the front of the cooking

chamber, and may cover not only the cooking chamber but also a front of

an upper space of the cooking chamber. A display and a touch panel, and

the like may be installed on a front surface of the door 20 with respect to

89932573.1 the upper space of the cooking chamber. As shown in FIG. 19, the display

90 and the touch panel 100 are connected to the controller 80. The

controller 80 may be installed on an upper space of the cooking chamber

or in the door 20 corresponding to the upper space of the cooking chamber.

[135] A latch module 4 is provided at an upper side of the main body 10. The

latch module 4 maintains a state where the door 20 is closed, or allows for

manually opening or closing of the door 20, or automatically opens the

door 20, or securely locks the door 20 so that the door cannot to be

manually opened. A pin 22 that is engaged with or released from a hook 51

of a latch 50 of the latch module 4 and an accommodation 21 that has the

pin 22 are provided on a rear surface of the door 20 (see, for example, FIG.

9(a)). The accommodation 21 provides a space capable of accommodating

the hook 51.

[136] The latch module 4 may be installed on the main body 10 and a distal end

of the latch 50 of the latch module 4, i.e., the hook 51 may protrude forward

from the front surface of the main body 10.

[137] The latch module 4 may be installed at one side on the door or on both

sides of the door, and the pin 22 and the accommodation 21 of the door

may be provided corresponding to the latch module.

[138] FIGS. 2 and 3 illustrate a hinge module 300 that connects a door and a main

body of a cooking device according to an embodiment of the invention.

The hinge module 300 includes a spring 323, a damper 350, and a sub

89932573.1 spring 370, and is connected to a front lower portion of the main body and a lower portion of the door. The spring 323 applies a force of moving the door in a direction of rotating a door 20 rearward and upward, i.e., the direction of closing the door. Accordingly, the spring 323 opposes a force opening the door while the door is being opened and descending.

[139] Further, while the door is being opened, the damper 350 damps a rotational

force of the door to cause the door to be opened slowly. As necessary, the

damper 350 may only provide a damping force while the door is being

opened, or may provide the damping force while the door is being opened

and while the door is being closed. The damping force may be provided in

all rotation angles in which the door is opened and/or closed, or the

damping force may be provided in a range among the rotation angles.

[140] The damper 350 may damp a force of opening the door at a predetermined

opening angle section of the door and may not provide the damping force

in a section beyond the opening angle section in which the damping force

is provided. FIG. 1 shows a structure in which the damper is damping in an

opening angle section of an opening door corresponding to a2 to a3. A

damping beginning in angle a2 in which the damping starts when the door

is being opened may be 35± 5.

[141] The sub-spring 370 applies a force in a direction of opening the door 20.

An opening angle range in which the sub-spring 370 applies the force in

89932573.1 the direction of opening the door may be 0° to al.

[142] [Operation of automatically opening door]

[143] Hereinafter, an operation of automatically opening a door will be described

with reference to FIGS. 1 to 3. In this embodiment, when a user touches a

touch panel and the like to input a command of opening the door, a latch

module 4, which will be described later, releases an engaged state of the

closed door. The door is opened by an elastic force of the sub-spring 370

of the hinge module 300 to an initial opening angle al. The predetermined

angle al may be set to such an extent that the door may be subsequently

further opened by the weight of the door itself. The angle al may be, for

example, about 10.

[144] The hinge module 300 connecting the main body 10 and the door 20

includes a door bar 340 fixed to the door 20 and a housing 310 fixed to the

main body 10 that rotate about an opening and closing rotational shaft 314.

In another embodiment, the bar may be fixed to the main body and the

housing may be fixed to the door.

[145] In the housing 310, an inner link housing 330 is provided which is movable

along a longitudinal direction of the housing. A distal end of the inner link

housing 330 is connected to the door bar 340 by a door bar connecting

hinge 331. As the door bar connecting hinge 331 is disposed eccentric from

the opening and closing rotational shaft 314 by a distance of r, when the

89932573.1 door 20 (the door bar 340) opens, the door bar connecting hinge 331 rotates about the opening and closing rotational shaft 314 and moves forward.

Accordingly, the inner link housing 330 also moves forward in the housing

310.

[146] As the door 20 or the door bar 340 is opened from a closed state (vertical

state) to an opened state (horizontal state) while being rotated forward of

the main body, a maximum opening angle a3 is 90. Accordingly, the

connecting hinge 331 also rotates by 90° about the opening and closing

rotational shaft 314. The inner link housing 330 also moves forward by a

horizontal distance d3 in which the opening and closing rotational shaft

314 rotates by 90°.

[147] An insert pin 361 is installed in front of the inner link housing 330. A slot

pin 362 provided in front of the insert pin 361 and is fitted into a guide slot

333 formed longitudually at both sides of the inner link housing 330.

Accordingly, the insert pin 361 is slidably installed forwardly and

rearwardly in the inner link housing 330 within a range allowed by the

guide slot 333. The insert pin 361 is inserted into the sub-spring 370. A

front portion of the sub-spring 370 is supported by the slot pin 362 and the

rear portion thereof is supported by the inner link housing 330. Accordingly,

the sub-spring 370 applies the force of moving the slot pin 362 forward

through the guide slot 333.

89932573.1

[148] A contact surface 363 of the slot pin 362 pushes an inclined surface

provided at a lower rear end of the door bar 340 forward. As shown in FIGS.

2 and 3, as a height at which the slot pin 362 pushes the inclined surface

forward is higher than a position of the opening and closing rotational shaft

314, at the beginning of opening the door, in the state where the door bar

340 stands vertically (closed state), the sub-spring 370 applies the force of

moving the door bar 340 in a direction of rotating the door bar 340 forward

and downward. Accordingly, at the beginning of opening the door, the sub

spring 370 opens the door by the initial opening angle al. After the slot pin

362 moves to the foremost position of the guide slot 333, the slot pin 362

does not move further and the sub-spring 370 does not apply force on the

door bar 340.

[149] Of course, in the section corresponding to the state where the door is closed

to the state where the opening angle of the door is the initial opening angle

al, a pressing force of the spring 323 in the direction of closing the door is

less than a pressing force of the sub-spring 370 in the direction of opening

the door. Thus, in this section, the net force is a force applied to the door in

the opening direction thereof.

[150] Note that in a closed state of the door, a force which is transferred from the

pin 22 to the hook 51 of the latch 50 to move the latch in a second direction

w2 (see FIG. 6) by an opening force of the sub-spring 370 is weaker than

a force which is applied to the latch 50 to move the latch in a first direction

89932573.1 wl by a spring in the latch module 4 (for example, see FIG. 4), when the latch 50 is in a manual lock state, and thus the door maintains the closed state in spite of the force of the sub-spring 370 of a hinge module 300 to open the door.

[151] After the door reaches the initial opening angle al from the closed state,

the door starts to open by the weight of the door itself. As the door bar 340

rotates about the housing 310 to further open the door, a damping force

along with an opposing force against the door being opened are exerted on

the door bar 340 by a damper 350 and a spring 323 to be described later.

[152] A second insert pin 320 inserted inside of the spring 323 is installed at a

rear of the inner link housing 330. The second insert pin 320 is connected

to the rear of the inner link housing 330 through ajoint pin 322 at the inner

housing. Both ends of the joint pin 322 at the inner housing are fitted to a

guide slot 315 provided at the housing 310. The guide slot 315 for the joint

pin 322 has an elongated shape extending along the longitudinal direction

of the housing 310.

[153] The second insert pin 320 is inserted into the compressed coil spring 323

having greater elasticity in a compressed state. The second insert pin 320

may slidably move along the longitudinal direction of the housing 310

through a spring-engaged plate 311 fixed to the housing 310. However; the

distal end of the compressed coil spring 323 is engaged with the spring

engaged plate 311 of the housing 310 and a supporting pin 312 that

89932573.1 supports the spring-engaged plate 311 maybe installed in the housing 310 so as to maintain the force of the compressed coil spring 323.

[154] A spring supporting pin 321 that fixes a rear end of the spring 323 is

installed at a rear end of the second insert pin 320. The spring supporting

pin 321 does not interfere with the housing 310.

[155] Accordingly, when the door bar 340 opens from the main body 20, the joint

pin 322 of the inner link housing 330 is guided by the guide slot 315 of the

housing 310, and the inner link housing 330 and the second insert pin 320

are moved forward. Accordingly, the spring 323 starts to compress between

the spring-engaged plate 311 and the spring supporting pin 321, and the

elastic force is gradually increased. The compression length d3 of the

spring 323 corresponds to the horizontal movement distance d3 of the inner

link housing 330 in which the opening and closing rotational shaft 314

rotates by 90. When the opening angle of the door is less, the elastic force

of the spring 323 is less. However, as the opening angle of the door is

increased, the elastic force of the spring 323 is increased. The elastic force

is applied in a direction of opposing the door being opened.

[156] A force in which the spring 323 pushes the door in the closing direction

thereof when the door is opening is gradually increased from the opening

angle al to the opening angle a3 of the door. As the force of the spring 323

at the opening angle al of the door is less than the force (the opening force)

in which the door is opened by the weight of the door itself at the opening

89932573.1 angle al, the door pushed to the opening angle al by the sub-spring 370 starts to open by itself.

[157] The damper 350 is installed in the inner link housing 330. A piston 351 of

the damper 350 is supported by a damper pushing surface 332 integrally

fixed to the inner link housing 330. The piston 531 is inserted into a

cylinder 352. A slot 353, in which a damper supporting pin 313 fixed to the

housing 310 is fitted into is provided at the cylinder 352. That is, the

cylinder 352 may move forward or backward by the length of the slot 353.

FIG. 3 shows a position between the slot 353 of the damper 350 and the

damper supporting pin 313 of the housing 310 while the door is closed.

[158] As the door opens and is rotated by a predetermined angle a2, the inner link

housing 330 moves forward in the horizontal direction by distance d2.

Accordingly, the damper 350 is moved forward by the damper pushing

surface 332 of the inner link housing 330 and moves together. As the

damper is pushed forward, the damper pushing surface 332 pushes the

piston 351 forward; however, the slot 353 of the cylinder 352 has not

engaged with the damper supporting pin 313. Thus, the piston 351 and the

cylinder 352 move forward together with the inner link housing 330, and

does not generate any damping force.

[159] As soon as the opening angle of the door exceeds a2, the slot 353 of the

damper 350, which has been moving forward, is engaged with the damper

supporting pin 313, so that the cylinder 352 stops moving and the piston

89932573.1

351 engages with the cylinder 352 such that the damper 350 starts to

compress. The damping force generated when the damper 350 compresses

enables opening the door at a controlled speed in the section corresponding

to the opening angle a2 to a3.

[160] For reference, a maximum damping distance (Lmax) of the damper 350

itself, that is, a maximum stroke capable of generating the damping force

by compressing in the damper, is set to be equal to or greater than the

distance d3-d2 in which the inner link housing 330 moves while the

damping force is applied to the door.

[161] When the closed door is opening to opening angle a2, the door bar

connecting hinge 331 also rotates by angle a2, so that the inner link housing

330 and the second insert pin 320 move forward by distance d2. While the

inner link housing 330 and the second insert pin 320 inserted inside of the

spring 323 move by the distance d2, the slot 353 of the damper 350 moves

without interference from the damper supporting pin 313 of the housing

330, and thus the piston 351 and the cylinder 352 of the damper do not

engage. That is, in the section corresponding to the opening angle of 0 to

a2 of the door, the elastic force of the spring 323 is applied in a direction

opposite to the opening force of the door to control the opening speed of

the door, but the damping force is not applied.

[162] When the closed door is opening to opening angle a3, the door bar

connecting hinge 331 also rotates by angle a3, so that the inner link housing

89932573.1

330 and the second insert pin 320 move forward by distance d3. That is,

the spring 323 is compressed by distance d3. That is, the elastic force of

the spring 323 is applied in a direction opposite to the opening force of the

door in the section from 0 to a3 of the opening angle, and an opening

speed of the door is controlled by the elastic force.

[163] The maximum opening angle a3 may be regulated by the guide slot 315 of

the housing 310 by regulating a slidable movement distance of thejoint pin

322 of the inner link housing 330 within the guide slot 315.

[164] The angle range in which the damper 350 damps the opening force of the

door may start when the door is rotated about 30 to 400, for example, and

may be continued until the door is rotated by 90. To summarize, the door

is opened in a closed state by the sub-spring 370 to the initial opening angle

al, and then opened by its own weight while being opposed by the elastic

force of the spring 323. When the door is rotated by opening angle a2

(about 300 to 40), the damping force of the damper 350 is applied to the

door so that the opening speed of the door is slowed down. The manner of

opening the door as described above makes the user feel comfortable.

[165] Note that if the damping starts too early as the door is opening, time for

waiting for the door to be completely opened may take too long, resulting

in an inconvenience to the user. On the other hand, if the damping of the

89932573.1 door starts too late, the door may be opening too quickly to an extent that the opening speed of the door is too fast, and thereby the user may be surprised or feel uncomfortable, or the user may get injured by the quickly opening door.

[166] Thus, according to the embodiment, the damping beginning angle a2 at

which the damper 350 starts to damp the opening force of the door is 35

50.

[167] The damping force may be continuously applied up to 900 at which the

door is completely opened or up to 850 which is about 50 less. It is also

conceivable that the damping force is not applied for an opening angle

greater than 85 0to prevent the door from being opened less than 1 0to 20

of the 9 0 °required to completely open the door.

[168] As described above, the damping beginning angle a2 is set to be greater

than the forcedly opened angle al. A section between the forcedly opened

angle al and the damping beginning angle a2, for example, a range of 100

or more and 300 to 400 or less is configured so that the door is opened by

the weight of the door itself without being damped by any damper 350. Of

course, even in this section, the above-described elastic force of the spring

323 is applied in a direction that opposes the opening of the door, so that

89932573.1 the opening of the door is sufficiently prevented from opening too quickly in the section in which the door is opening by the weight of the door itself.

[169] When such a structure of automatically opening the door is applied, it is

possible to reduce user anxiety, and increase a quality of the door being

opened automatically, and there may be no need to install a handle

protruding forward from the door, thereby providing excellent appearance

to the user in the built-in installation.

[170] [Latch Module]

[171] Hereinafter, according to an embodiment, a latch module 4 capable of

automatically opening a door or completely locking a door of a cooking

device will be described with reference to FIGS. 4 to 13(b).

[172] According to the embodiment, the latch module 4 includes a bracket 40 as

an overall base. The bracket 40 may be made of sheet metal. An edge of a

rectangular metal plate is bent downward or upward. Accordingly, a

structure in which the latch module 4 may be fixed to another body and a

structure in which various parts, such as a drive 60, an elastic body 90, and

the like may be installed in the bracket 40 are provided.

[173] The bracket 40 includes a cam accommodating hole 42 that provides a

space that accommodates a cam 70 which is a power transmitting portion

and an through-hole 41 capable of regulating a section in which a latch 50

pivotally installed in the bracket 40 pivots.

[174] The latch 50 is pivotally installed on the bracket 40. The latch 50 has a

89932573.1 structure having a bent long metal plate, and a rear end of the latch 50 is provided with a pivot shaft 54 as a center of pivot of the latch 50 about the bracket 40. As the pivot shaft 54 is installed in a pivot hole (not shown), the latch 50 is pivotally installed on the bracket 40.

[175] A rear portion of the latch 50 including the pivot shaft 54 is arranged over

the bracket 40. On one side of the latch 50 arranged over the bracket 40, a

contact surface 55 is provided to be in contact with a latch position

adjusting profile 73 of the cam 70 and an extension 58 is provided that

interacts with the cam 70 to mechanically complement an operation error

of the latch 50. The extension 58 extends vertically from the contact surface

55 and a substantially 'L'-shape is formed between the contact surface 55

and the extension 58.

[176] An insertion portion 56 is formed at an intermediate portion of the latch 50

that is bent downward and forward so as to decline from a front end of the

rear portion and is inserted through the through-hole 41 of the bracket 40.

The through-hole 41 has an arc shape and has a size that accommodates a

locus of the swivel of the latch 50 when the insertion portion 56 is inserted

into the through-hole 41.

[177] An arc-shaped sliding bead surface 43 that supports the pivoting of the

latch 50 is provided at a position closer to the pivot shaft 54 than the

through-hole 41 at the bracket 40. The sliding bead surface 43 protrudes

from the surface of the bracket 40 to contact a bottom surface of the latch

89932573.1

50, thereby preventing friction from occurring via a direct contact of a top

surface of the bracket 40 and the bottom surface of the latch 50.

[178] A front end of the insertion portion 56 is bent forward again to extend

forward in the horizontal direction, i.e., parallel with the rear portion. A

hook 51 is provided at a distal end of the latch 50. The hook 51 engages

with or releases from a pin 22 of the door.

[179] The latch 50 includes a hole 57 capable of engaging with an end of a spring

90 that acts as an elastic force. The spring 90 has one end fixed to the hole

57 and an other end fixed to the bracket 40. Accordingly, the spring 90 pulls

the latch 50 towards the spring. The spring 90 is arranged to be adjacent to

a first direction wl of the pivoting direction of the latch 50 and applies a

force so as to pivot the latch 50 in the first direction wI.

[180] The cam 70 is rotatably installed to be adjacent to the first direction wl of

the latch 50. A hole 711 as the center of rotation of the cam 70 is disposed

vertically on the cam so that the cam 70 has a vertical rotational axis. The

cam 70 is installed into the cam accommodating hole 42 of the bracket 40

so that an upper portion of the cam 70 is exposed over the bracket 40 and

a lower portion of the cam 70 is exposed below the bracket 40.

[181] The cam 70 includes the latch position adjusting profile 73 that contacts

the contact surface 55 of the latch 50 described above and adjusts the

position of the latch 50 based on a rotational position of the latch position

adjusting profile 73, and a switch pressing profile 72 that presses the

89932573.1 switches 81 and 82 to be described later or press-releases the switches 81 and 82.

[182] The latch position adjusting profile 73 is provided at the upper portion of

the cam, and the switch pressing profile 72 is provided at the lower portion

of the cam. The latch position adjusting profile 73 is exposed above the

bracket 40 and contacts the contact surface 55 of the latch 50 when the cam

70 is installed on the bracket 40. The switch pressing profile 72 is exposed

below the bracket 40 and presses or press-releases the switches 81 and 82

to be described later provided at the lower portion of the bracket 40.

[183] For reference, a material of the cam 70 may be a synthetic resin having

good strength and heat resistance, such as poly phenylene sulfide (PPS),

and thereby abrasion generated when the cam rotates is minimized and

stability in an environment of the home appliance having high temperature

may be provided.

[184] The cam 70 is rotationally driven by a motor 60 as a driver. According to

the embodiment, the cam 70 may be directly connected to the rotational

shaft 61 of the motor 60. The motor 60 may be a bi-directional rotational

motor capable of both clockwise rotation and counter-clockwise rotation.

The motor 60 is fixed to the upper portion of the bracket 40 such that the

rotational shaft 61 extends downward and the rotational shaft 61 is inserted

into the axis hole 711 of the cam 70.

[185] The first switch 81 and the second switch 82 are installed at the bottom

89932573.1 surface of the bracket 40. The first switch 81 and the second switch 82 may be a micro switch having buttons 811 and 812, respectively. The buttons

811 and 812 of the switches provided on the bracket protrude to

substantially face a center of the cam. The buttons 811 and 812 are arranged

with an angle b of 90 or more and less than 1800 with respect to the

center of rotation 711 of the cam and may be arranged at the same distance

from the center of rotation of the cam. Preferably, the angle b may be in the

range of 1100 to 1600, and more preferably in the range of 120.

[186] <Latch>

[187] Referring to FIG. 6, a latch according to an embodiment will be described.

The hook 51 is provided at the distal end of the latch 50, that is, a front end

thereof, is opened laterally, specifically, in a first direction w Iin which the

latch 50 pivots. Inward of the hook 51, an engaging surface 52 that engages

with the pin 22 of the door is provided. The engaging surface 52 includes

a disengaging inclined surface 521 and a secure lock surface 522. The

disengaging inclined surface 521 is arranged closer to the first direction wI

on the engaging surface 52 and the secure lock surface 522 is arranged

closer to a second direction w Iin which the latch 50 pivots in the engaging

surface 52. That is, the disengaging inclined surface 521 is arranged closer

to the opening end of the hook 51 than the secure lock surface 522 which

is arranged deeper into the hook 51.

89932573.1

[188] The disengaging inclined surface 521 has a surface inclined with respect to

a horizontal axis in an opening direction of the door toward the first

direction wl. When the latch 50 pivots about a pivot shaft 54 in the first

direction wl, the pin 22 of the door contacts the disengaging inclined

surface 521 and the latch 50 is disposed in the manual lock position.

[189] The secure lock surface 522 has a surface inclined with respect to the

horizontal axis in the closing direction of the door toward the second

direction w2. When the latch 50 pivots further in the first direction wl, the

pin 22 contacts the secure lock surface 522 and the latch 50 is disposed in

a secure lock position.

[190] The disengaging inclined surface 521 and the secure lock surface 522 are

connected with a smooth curved surface. Thus, as the latch 50 pivots, when

the pin 22 of the door in contact with the disengaging inclined surface 521

slides adjacent to the secure lock surface 522, the sliding may be smoothly

made over to the secure lock surface 522. In particular, as the movement

of the latch 50 is made by an elastic force of the spring 90, the movement

of the latch 50 may be more reliably made if the sliding between the

disengaging inclined surface 521 and the secure lock surface 522 is made

smooth.

[191] An inclined insertion surface 53 is provided on an outer surface of the hook

51 opposite to the disengaging inclined surface 521. The inclined insertion

surface 53 is inclined with respect to the horizontal axis in the closing

89932573.1 direction of the door toward the second direction w2 when the latch 50 is in the manual lock position. The inclined insertion surface 53 contacts the surface of the pin 22 of the door when the latch is in the manual lock position. That is, the hook 51 has a shape that gradually becomes thinner, that is, sharper, toward the end by the disengaging inclined surface 521 and the inclined insertion surface 53. The inclined insertion surface 53 may extend to the outer surface of the hook 51 that is opposite to the secure lock surface 522.

[192] The contact surface 55 of the latch 50 in contact with the cam 70 is provided

at the side of the latch 50. The contact surface 55 is arranged in adjacent to

a second direction w2 about the center of rotation of the cam. An extension

58 extending outward from the contact surface 55 is further provided at one

end of the contact surface 55. The extension 58 and the contact surface 55

have a substantially 'L'-shape and the contact surface 55 and the extension

58 are arranged to surround the cam 70.

[193] An sub-contact surface 59 is provided laterally with respect to an extending

direction of the extension 58, which faces the cam, and in some cases

contacts and interacts with the surface of the cam. The sub-contact surface

59 protrudes from the extension 58 so that other than the sub-contact

surface 59, other portions of the extension 58 does not interact with the

cam 70.

[194] The sub-contact surface 59 approaches the surface of the cam 70 when the

89932573.1 latch 50 pivots in the first direction wl. The sub-contact surface 59 moves in a direction away from the cam as the latch 50 pivots in the second direction w2.

[195] The extension 58 is not necessarily integrally formed with a body of the

latch 50, but may be manufactured as a separate component and then

assembled. The extension 58 does not have to behave like a rigid body with

the body of the latch 50. It is enough for the extension 58 to transmit such

a force to the body of the latch 50 that the cam 70 moves the extension 58

in the first direction wl and the latch 50 moves from a first basic position

(see FIG. 9(b)) to a third basic position (see FIG. 13(b)) or the latch is in

the third basic position.

[196] When the force is applied to the contact surface 55 of the latch 50 by the

cam 70 in the second direction w2, that is, the latch 50 is pivoted from the

first basic position to the second basic position (see FIG. 10(b)) by the cam

70, the extension 58 does not interact with the cam 70.

[197] A feature of the sub-contact surface 59 will now be described. The cam

may include an oblong shape. When the cam 70 rotates and the radius of

the cam 70 in contact with the contact surface 55 of the latch 50 is reduced,

the latch 50 pivots in the first direction wl, and the radius of the cam 70

that faces the sub-contact surface 59 of the latch 50 increases. When the

latch 50 does not pivot in the first direction wl although the radius of the

cam 70 contacting the contact surface 55 of the latch is reduced so that the

89932573.1 latch 50 can pivot in the first direction wl, the radius of the cam 70 that faces the sub-contact surface 59 increases sufficiently as to interact with the sub-contact surface 59, and the sub-contact surface 59 is pushed in a direction away from the cam 70 so that the latch 50 may be forcedly pivoted in the first direction wl.

[198] A distance dmp between the center of rotation of the cam 70 and the sub

contact surface 59 when the latch 50 is in the first basic position (see FIG.

9(b)) and a distance dop between a center of rotation of the cam 70 and the

sub-contact surface 59 when the latch 50 is in the second basic position

(see FIG. 10(b)), and a distance dlp between the center of rotation of the

cam and the sub-contact surface when the latch is in the third basic position

(see FIG. 13(b)) has a relationship of dop < dmp < dlp.

[199] <Cam>

[200] Referring to FIGS. 5, 7, and 8, a cam according to an embodiment will be

described. A latch position adjusting profile 73 of the cam 70 includes three

surfaces having different radiuses from one another, that is, a contact

surface for manual lock 731, a contact surface for automatic opening 732

and a contact surface for secure lock 733. The three surfaces have different

radiuses from one another and are connected to each other by a connecting

surface 734 that has a gradually increasing or reducing radius, respectively.

[201] The contact surface for manual lock 731 includes a first radius. The first

radius may be configured such that the latch 50 is disposed at a position

89932573.1 where the door may be manually opened and closed in a state in which the first radius contacts the latch 50. In this state, the pin 22 of the door contacts the disengaging inclined surface 521 or the inclined insertion surface 53 of the hook 51. Accordingly, the spring 90 pulls the latch 50 in the first direction wl and the contact surface for manual lock 731 of the cam 70 contacts the latch 50 (see FIGS. 9(a), 9(b) or 12(a), 12(b)). In this state, when the user pulls the door in the opening direction thereof, the door may be opened. When the user closes the door, the door may be closed.

[202] The contact surface for automatic opening 732 includes a second radius.

The second radius is configured so that the latch 50 may be rotated in the

second direction w2 to the position in which the latch 50 is released from

the pin 22 of the door in a state in which the second radius contacts the

latch 50. The second radius has a radius greater than the first radius. That

is, when the spring 90 pulls the latch 50 in the first direction wl and the

contact surface for automatic opening 732 of the cam contacts the latch 50

(see FIGS. 10(a), 10(b) or 11(a), 11(b)), the latch 50 is released from the

pin 22 of the door.

[203] The contact surface for secure lock 733 includes a third radius. The third

radius is configured such that the latch 50 completely securely locks the

door while being in contact with the latch 50 so that the door cannot be

opened even when the door is pulled to open by the user. In this state, the

pin 22 of the door contacts the secure lock surface 522 of the hook 51. Thus,

89932573.1 when the spring 90 pulls the latch 50 in the first direction wl and the contact surface for secure lock 733 of the cam 70 contacts the latch 50 (see

FIGS. 13(a), 13(b)), even if the user pulls the door in the opening direction,

the door may not open. That is, the state may be referred to as a completely

locked state, for example, for self-cleaning.

[204] A diameter rM1 of a cam surface in contact with the sub-contact surface 59

when the cam is in the first mode and the first radius of the cam contacts

the contact surface of the latch (see FIG. 9(b)), a diameter rM2 of a cam

surface that faces the sub-contact surface 59 when the cam is in the second

mode and the second radius of the cam contacts the contact surface of the

latch (see FIG. 10(b)), and a diameter rM3 of a cam surface that faces the

sub-contact surface 59 when the cam is in the third mode and the third

radius of the cam contacts the contact surface of the latch (see FIG. 13(b))

have a relation of rM2 rM1 rM3.

[205] When the cam is in the first mode state, and the first radius 731 contacts

the contact surface 55 of the latch 50, a portion of the cam surface that faces

the sub-contact surface 59 may be the first radius 731, the third radius 733

or a connecting surface 734 connecting the first radius 731 and the third

radius 733. According to the present disclosure, FIGS. 9(b) and 12(b) show

that the cam surface that faces the sub-contact surface 59 is the first radius

731.

[206] When the cam is in the second mode, and the second radius 732 is in a

89932573.1 position in contact with the contact surface 55 of the latch 50, the cam surface that faces the sub-contact surface 59 may be the first radius 731

(see FIGS. 10(b) and 1(b)).

[207] When the cam is in the third mode, and the third radius 733 is in the position

in contact with the contact surface 55 of the latch 50, the cam surface in

contact with the sub-contact surface 59 may be the second radius 732 (see

FIG. 13(b)).

[208] As shown in FIG. 9(b), when the cam 70 is in the first mode state, and the

first radius 731 contacts the contact surface 55 of the latch 50, the radius

rM1 of the cam surface that faces the sub-contact surface 59 is less than a

distance dmp between a position mp of the sub-contact surface 59 and the

center of rotation 711 of the cam 70 when the latch 50 is in the first basic

position, and is equal to or less than the distance dop between the position

op of the sub-contact surface 59 and the center of rotation 711 of the cam

70 when the latch 50 is in the second basic position (see FIG. 10(b)). That

is, the relation of rM1 dop < dmp is satisfied.

[209] As shown in FIG. 10(b), when the cam 70 is in the second mode state, and

the second radius 732 contacts the contact surface 55 of the latch 50, the

radius rM2 of the cam surface that faces the sub-contact surface 59 is equal

to or less than the distance dop between the position op of the sub-contact

surface 59 and the center of rotation 711 of the cam 70 when the latch 50

89932573.1 is in the second basic position. That is, rM2 dop.

[210] As shown in FIGS. 9(b) and 10(b), the relation of rM1 rM2 dop <

dmp may be expressed based on the conditions.

[211] As shown in FIG. 13(b), when the cam is in the third mode state, and the

third radius 733 of the cam 70 contacts the contact surface 55 of the latch

50, a radius rM3 of the cam surface that faces the sub-contact surface 59 is

greater than a distance dmp between the position mp of the sub-contact

surface 59 and the center or rotation 711 of the cam 70 with the latch 50

being in the first basic position and is equal to or less than a distance dlp

between a position lp of the sub-contact surface 59 and the center of

rotation 711 of the cam 70 with the latch 50 is in the third basic position.

That is, the relation of dmp < rM3 dlp is satisfied.

[212] All of the above conditions are expressed as follows:

[213] rM1I rM2 dop < dmp < rM3 dlp.

[214] On the other hand, a switch pressing profile 72 of the cam 70 has two

pressing bosses having substantially the same radius. A first pressing boss

721 and a second pressing boss 722 are not arranged in a straight line, that

is 1800 opposite from each other, but are disposed at an obtuse angle. The

angle of the two pressing bosses may correspond to an angle between the

89932573.1 buttons 811 and 812 of the first switch and the second switch, and the radius of the two pressing bosses may be configured such that the pressing boss presses or press-releases the button as the cam rotates.

[215] The first pressing boss may press the first switch or the second switch or

not press the two switches depending on the rotational position of the cam.

The second pressing boss may press the first switch or the second switch

or not press both switches depending on the rotational direction of the cam.

[216] Since the angle of the two pressing bosses corresponds to the angle of the

buttons of the two switches, the state where the first pressing boss presses

the first switch and the second pressing boss presses the second switch, that

is, a first mode state where the two pressing bosses press the two switches,

a second mode state where the second pressing boss presses the first switch

and the first pressing boss does not press a switch, a third mode state where

the first pressing boss presses the second switch and the second pressing

boss does not press a switch, and a fourth mode state where the two

pressing bosses do not press any switches may be implemented.

[217] Each mode of the switch pressing profile 72 and the latch position adjusting

profile 73 may be related to each other. That is, in the first mode, the contact

surface for manual lock 731 may contact the latch to dispose the latch in

the manual lock state. In the second mode, the contact surface for automatic

opening 732 may contact the latch so that the latch is in the open position.

In the third mode, the contact surface for secure lock 733 may contact the

89932573.1 latch so that the latch is disposed in the secure lock position.

[218] [Operation of Latch Module]

[219] Hereinafter, an operation of a latch module according to an embodiment

will be described with reference to FIGS. 9 to 13(b).

[220] < Manual Lock State>

[221] FIGS. 9(a) and 9(b) illustrate a manual lock state. A latch module is

provided. That is, when the two pressing bosses 721 and 722 press the

buttons 811 and 812 of the two switches, respectively, a contact surface for

manual lock 731 which is a first radius of the latch position adjusting

profile 73 contacts a contact surface 55 of a latch 50. The spring 90 pulls

the latch 50 in the first direction w I(a direction in which the hook 51 pivots

leftward in FIG. 9(a)).

[222] When the user pulls the door 20 in such a manual lock state, a rear surface

of the pin 22 presses on the disengaging inclined surface 521 of the hook

51. The disengaging inclined surface 521 is inclined outward toward the

first direction wl so that the force is applied to the hook 50 in the second

direction w2 by a force in which the pin 22 presses on the disengaging

inclined surface 521, and accordingly, the latch 50 pivots in the second

direction w2 with a force greater than the elastic force of the spring 90 (i.e.,

as the latch 50 pivots in the second direction w2, the contact surface 55 of

the latch moves away from the contact surface for manual lock 731). As a

result, the hook 51 that is engaged with the pin 22 is released so that the

89932573.1 door is opened.

[223] As described above, as the relation of rM1 dop < dmp is satisfied, the

extension 58 does not interact with the cam during the pivot of the latch 50

in the second direction w2 for the manual opening of the door and the latch

50 may freely rotate in the second direction w2.

[224] When the door is opened and the pin 22 is released from the hook 51, as a

force in which the pin 22 pushes the hook 51 in the second direction

disappears, the latch 50 pivots in the first direction wl by means of the

spring 90 until the contact surface 55 of the latch 50 contacts the contact

surface for manual lock 731, so that the latch is returned to a manual lock

position as shown in FIGS .12(a) and 12(b).

[225] In this state, when the user closes the door as shown in FIG. 12(a), the

surface of the pin 22 pushes the inclined insertion surface 53 of the hook

51. As the inclined insertion surface 53 has a form inclined to a closing

direction of the door toward the first direction wl, a force of pivoting in

the second direction w2 is applied to the hook 51 in which the surface of

the pin 22 presses against the inclined insertion surface 53 in the closing

direction. Then, the latch 50 pivots in the second direction w2 with a force

greater than the elastic force of the spring 90. As the door is closed, the

force on the hook 51 is released from a locus of the moving pin 22. As

shown in FIG. 9(a), when the door is closed, via the elastic force of the

spring 90, the latch pivots again and returns in the first direction w2 by the

89932573.1 elastic force of the spring until the contact surface 55 of the latch 50 contacts the contact surface for manual lock 731.

[226] Similarly, as the relation of rMl 5 dop < dmp is satisfied, during the pivot

of the latch 50 in the second direction w2 for manual closing the door, the

extension 58 is not interfered with the cam 70 and the latch 50 may freely

move in the second direction w2.

[227] As described above, according to the embodiment, with the latch module

4, it is possible to open the door by manually pulling the door by the user,

or close the door by pushing the door toward the main body.

[228] <Automatic opening operation>

[229] An Automatic opening operation of the latch module according to an

embodiment will now be described. As shown in FIG. 9(a), when the user

inputs an automatic opening command of a door through an input device,

a bidirectional rotational motor 60 rotates in any one direction, that is, a

first rotational direction by a controller 80, and the cam 70 is rotated in a

first rotational direction cI. Then, a pressed state of the two switches is

released, and the cam 70 continues to rotate. As shown in FIG. 10(a), the

rotation of the cam 70 continues until a second pressing boss 722 presses a

first switch 81. When the second pressing boss 722 presses the first switch

81, the bidirectional rotational motor 60 is stopped by the controller 80 that

senses the pressed state, and the rotation of the cam in the first rotational

89932573.1 direction cl is also stopped. That is, the cam 70 is rotated in the first rotational direction c I by an angle b of the two pressing bosses and stopped

(see FIG. 7).

[230] As shown in FIG. 10(a), as the first pressing boss 721 and the second

pressing boss 722 are not on a straight line passing through a center of

rotation 711 of the cam 70 and have an obtuse angle, the second pressing

boss 722 presses the first switch 81 while the first pressing boss 721 does

not press the second switch 82.

[231] As the latch 50 is elastically supported by the spring in a direction in

contact with the cam 70, the latch pivots while being in contact with the

latch position adjusting profile 73 of the cam 70 depending on the radius

of the latch position adjusting profile 73 during the rotation of the cam 70.

As the cam 70 is rotated by the angle b in the first rotational direction cI,

a position of the latch position adjusting profile 73 contacting the contact

surface 55 of a latch 50 is moved from the contact surface for manual lock

731 to the contact surface for automatic opening 732 (as shown in FIG. 8,

the position of the latch position adjusting profile 73 contacting the contact

surface 55 of the latch 50 is moved from a vicinity of 250 (a contact

surface for manual lock 731) to a vicinity of 20° (a contact surface for

automatic opening 732) in a direction of increasing angle). As shown in

FIGS. 10(a) and 10(b), as the radius of the cam 70 in contact with the latch

89932573.1

50 is increased from the first radius to the second radius, the cam 70 pushes

the contact surface 55 of the latch 50 in a second direction w2 with a force

greater than an elastic force of the spring 90. Accordingly, the hook that is

locked with the pin 22 of the door is released.

[232] As described above, the relation of rMl < rM2 < dop <dmp is satisfied.

Further, while the cam 70 is moved from a first mode to a second mode, a

condition in which the radiuses rMl and rM2 of a cam surface that faces

the sub-contact surface 59 is less than distances dmp and dop between the

sub-contact surface 59 and the center of rotation of the cam is continuously

satisfied. Therefore, when the cam is rotated in the first rotational direction

c I for automatically opening the door and the latch is pivoted in the second

direction w2, the cam 70 does not interact with the extension 58 and the

latch 50 may freely rotate in the second direction w2.

[233] When the door is closed, that is, when an opening angle thereof is 0,

according to an embodiment, the sub-spring 370 of the hinge module 300

applies the elastic force in the direction of opening the door. Therefore, as

shown in FIG. 10(a), the door is moved in an opening direction od when

the hook 51 is no longer locked with the pin 22 as the latch 50 is moved in

the second direction w2 by the cam. As the sub-spring 370 of the hinge

module 300 applies the elastic force in a direction of opening the door when

the opening angle is 0°, an operation of opening the door instantly occurs

89932573.1 when the lock of the hook 51 with respect to the pin is released.

[234] For reference, the door would be opened at the position at which sum of

the force transmitted from the sub-spring 370 of the hinge module to the

hook 51 to move the latch 50 in the second direction w2 and the force of

the drive 60 is greater than the applied force of moving the latch 50 in a

first direction w Iby the elastic force of the spring 90, as the force of the

drive 60 is transmitted to the latch 50 and the latch 50 moves in the second

direction w2.

[235] Accordingly, when the door is opened by an initial opening angle al, the

door may automatically opened by its own weight.

[236] As shown in FIG. 11(a), as the bi-directional rotational motor 60 rotates in

the other direction, that is, a second rotational direction c2, the cam rotates

in a second rotational direction c2. Then, the pressing of the second

pressing boss 722 with respect to the first switch 81 is released. As shown

in FIG. 12(a), the rotation of the cam 70 in the second rotational direction

c2 continues until the two pressing bosses 721 and 722 push the two

switches 81 and 82, respectively. That is, the cam 70 is rotated in the second

rotational direction c2 by the angle b of the two pressing bosses and then

stopped (see FIG. 7).

[237] As described above, the automatic opening operation may be performed

continuously. That is, as shown in FIG. 9(a), when the command of

automatically opening the door is inputted, as the cam 70 is rotated in the

89932573.1 first rotational direction c l, the cam is moved to the position shown in FIGS.

10(a) and 11(b) by the angle b. Accordingly, the second pressing boss 722

presses the first switch 81, the cam 70 inversely rotates again in the second

rotational direction c2 so that the cam 70 is returned to the state as shown

in FIG. 9(a). As described above, the command of automatically opening

the door enables rotating the cam 70 in the first mode by the angle bl in

the first rotational direction c I and moving the cam 70 in the second mode,

and immediately returning the cam to the first mode again. That is, in

accordance with the command of automatically opening the door, the cam

operates in the order of the first mode -- the rotation in the first rotational

direction (the fourth mode) -- the second mode -- the rotation in the

second rotational direction (the fourth mode) -- the first mode.

[238] <Secure lock operation>

[239] A secure lock operation according to an embodiment will now be described.

As shown in FIG. 9(a) in a general state, when a user inputs a self-cleaning

command through the input device, the controller 80 determines whether

the door is closed through a door sensor 88. If the door is closed, the

controller 80 controls the bidirectional rotational motor 60 to rotate in a

second rotational direction so that a cam 70 rotates in a second rotational

direction c2. The pressed state of the two switches are released and the cam

70 continues to rotate. As shown in FIG. 13(a), the rotation of the cam 70

continues until a first pressing boss 721 presses a second switch 82. When

89932573.1 the first pressing boss 721 presses the second switch 82, the bidirectional rotational motor 60 is stopped by the controller 80, and accordingly, the rotation of the cam in the second rotational direction c2 is stopped. That is, the cam 70 is stopped after being rotated in the second rotational direction c2 by the angle b of the two pressing bosses.

[240] As the first pressing boss and the second pressing boss are not on a straight

line passing through the center of rotation of the cam 70 and have an obtuse

angle, as shown in FIG. 13(a), the first pressing boss 721 presses the second

switch 82 while the second pressing boss 722 does not press the first switch

81.

[241] As the latch 50 has elastic force in the direction in contact with the cam 70

by the spring 90, while the cam 70 rotates, the latch 50 pivots depending

on the contact of radius of the latch position adjusting profile 73 of the cam

70. As the cam rotates in the second rotational direction c2 by the angle b,

the position of the latch position adjusting profile 73 contacting the contact

surface 55 of the latch 50 is moved from the contact surface for manual

lock 731 to the contact surface for secure lock 733 (as shown in FIG. 8, the

radius of the cam is decreased from about 250 (contact surface for manual

lock 731) to 110° (contact surface for secured lock 733)). Accordingly, the

radius of the cam 70 that contacts the latch 50 is reduced from the first

radius to the third radius, so that the spring 90 further pulls the latch 50 in

89932573.1 the first direction w Iinto the hook 51 as shown in FIG. 13(a). Accordingly, as the pin 22 of the door moves deeply into the hook 51, the rear surface of the pin 22 contacts the secure lock surface 522 of the hook 51. As the pin

22 of the door moves from the disengaging inclined surface 521 to the

secure lock surface 522, the disengaging inclined surface 521 and the

secure lock surface 522 may be connected via a smooth curved surface.

When the spring 90 pulls the latch 50, the pin may be naturally moved

smoothly from the disengaging inclined surface 521 to the secure lock

surface 522.

[242] The movement of the latch 50 in the first direction wl is made by the

elasticity of the spring 90. Therefore, if the pin 22 of the door is not

completely moved inside the hook 51 and is stuck in a transitory position

in the hook, or if the pivoting of the latch becomes stiff or is stuck due to

foreign substances and the like, even if the cam 70 rotates in the second

rotational direction c2 and moves from the first mode to the third mode, the

latch 50 may not pivot correspondingly to reach the third basic position

from the first basic position.

[243] However, as described above, the relation of dop < dmp < rM3 dlp is

satisfied. That is, a point at which the cam 70 contacts the contact surface

55 of the latch 50 is moved from the first radius 731 to the third radius 733

as the cam 70 rotates, the radius of the surface of the cam 70 that faces the

sub-contact surface 59 may exceed the distance dmp between the position

89932573.1 mp of the sub-contact surface 59 and the center of rotation 711 of the cam

70 when the latch 50 is in thefirst basic position.

[244] Therefore, even if the latch is engaged in the first basic position or between

the first basic position and the second basic position, which is further away

from the first basic position, while the cam 70 is rotated from the first mode

to the third mode, the cam surface contacts the sub-contact surface 59 of

the latch 50 and pushes the sub-contact surface 59 in the direction away

from the cam, causing a kinematic interference such that the latch 50 is

forcedly rotated in the first direction wI. Thus, the latch is surely moved to

the third basic position.

[245] As shown in FIG. 13(a), as the secure lock surface 522 is inclined in a

closing direction toward the first direction w, when the user pulls on the

door, the hook receives more force to pivot in the first direction wl.

Therefore, even if the user pulls on the door, the door may not be opened.

[246] In particular, if the relation of rM3= dlp is satisfied, the latch 50 may surely

reach the third basic position. When an external force is applied to the latch

50 disposed in the third basic position and the latch is pivoted in the second

direction w2, as the cam 70 already contacts the sub-contact surface 59 of

the latch 50, the pivoting of the latch 50 in the second direction w2 may be

surely prevented via the kinematic interference.

[247] In this state, a self-cleaning operation may proceed. The cavity is heated to

400°C and maintained for a few minutes. An inner temperature of the

89932573.1 cavity is measured by a temperature sensor 85. Even if the self-cleaning operation is completed, an internal temperature of the cavity is continuously monitored by the controller until the internal temperature falls.

[248] When the internal temperature is lowered to a safe level, the controller 80

rotates the bidirectional rotational motor 60 in the first rotational direction

cl and rotates the cam 70 in the first rotational direction cl. Then, the

pressing of the first pressing boss 721 with respect to the second switch 82

is released. As shown in FIG. 9(a), the rotation of the cam 70 in the first

rotational direction c I continues until the two pressing bosses 721 and 722

press the two switches 81 and 82, respectively. That is, the cam 70 is rotated

in the first rotational direction c Iby the angle b of the two pressing and

then stopped.

[249] From the position shown in FIG. 9(a), when the self-cleaning command is

inputted, the cam 70 is rotated by the angle b in the second rotational

direction c2 to the position shown in FIG. 13(a), and the first pressing boss

721 presses the second switch 82, the rotation of the bidirectional rotational

motor 60 and the cam 70 is stopped. Then, self-cleaning operation proceeds.

After the self-cleaning operation is completed, the cam 70 rotates in the

first rotational direction c Iand return to the state as shown in FIG. 9(a).

[250] As described above, the self-cleaning command enables rotating the cam

70 in the first mode by the angle b in the second rotational direction c2.

After the self-cleaning operation, the cam returns to the first mode again.

89932573.1

That is, according to the self-cleaning command of the door, the cam is

operated in the order of the first mode -- the rotation in the second

rotational direction (the fourth mode) -- the third mode -- the rotation in

the first rotational direction (fourth mode) -- the first mode.

[251] As described above, according to the embodiment, both the manual lock

state of the door, the automatic opening operation of the door, and the

secure lock operation of the door may be implemented by one latch, one

drive and one power transmitting portion.

[252] <Initial Position Search Control of Latch Module>

[253] Referring to Fig. 14, an initial position search control of latch module will

be described. The latch is in three basic positions such as the manual lock

position, the automatic opening position, and the secure lock position,

depending on whether the contact surface 55 of a latch 50 contacts any of

the radiuses 731, 732, 733 of the latch position adjusting profile 73.

[254] As described above, the rotational displacement of the cam 70 is controlled

by the two switches 81 and 82 and the switch pressing profile 72 of the cam

70. The controller 80 determines a rotational direction and a rotation or

non-rotation of a bidirectional rotational motor based on four modes of the

two switches 81 and 82 (the first mode in which the two switches are

pressed, the second mode in which the first switch is only pressed, the third

mode in which the second switch is only pressed, and the fourth mode in

which the two switches are not pressed) to control a rotational angle or a

89932573.1 rotation or non-rotation of the cam.

[255] As shown in FIG. 14, in a first mode M1 in which the switch pressing

profile 72 presses the two switches, the manual lock state (the state of FIGS.

10(a) and 12(a)) in which the first radius 731 of the latch position adjusting

profile 73 contacts the latch 10.

[256] In this state, when the cam 70 rotates in the first rotational direction C1, the

position of the latch position adjusting profile 73 in contact with the latch

50 is moved to the right side of the graph in FIG. 14. In this process, a first

pressing boss 721 of the cam 70 is moved in an angle between the two

switches shown in FIG. 15.

[257] When the switch pressing profile 72 of the cam 70 is moved to a position

corresponding to the second mode M2 in which the first switch is only

pressed and then stopped, it can be confirmed that the cam 70 and the latch

50 are in the automatic opening state (the state of FIGS. 10(a) and 11(a),

that is, the state in which the second radius 732 of the latch position

adjusting profile 73 of the cam 70 contacts the latch 50. The cam 70 that

has reached the second mode rotates again in the second rotational

direction c2 and moves from the second mode M2 to the first mode Ml.

[258] When the cam rotates in the second rotational direction C2 in the first mode

Ml, the latch position adjusting profile 73 in contact with the latch 50 is

moved to the left of the graph in FIG. 14. In this process, the a second

pressing boss 722 of the cam 70 is moved between the angles of the two

89932573.1 switches shown in FIG. 16.

[259] When the switch pressing profile 72 of the cam 70 is moved to a position

corresponding to a third mode M3 in which the second switch is only

pressed and then stopped, it can be confirmed that the cam 70 and the latch

50 are in the secure lock state (the state of FIG. 13(a), that is, the state in

which the third radius 733 of the latch position adjusting profile 73 of the

cam 70 contacts the latch 50. After the self-cleaning operation, the cam 70

that has reached the third mode rotates again in the first rotational direction

c I and moves from the third mode M3 to the first mode M1.

[260] As described above, the controller 80 determines the position of the cam

70 and controls the rotation of the cam 70 based on the state where at least

one of the switches is pressed, that is, the first mode, the second mode and

the third mode.

[261] However, in situations such as where the cooking device is turned off due

to a power failure, and the like and the cooking device is turned on again,

the controller needs to determine whether the current position of the cam

is in any one mode from the first mode to the fourth mode.

[262] As a result of determination, if the cam is currently in any one mode of the

first mode, the second mode and the third mode depending on the pressed

state of the switch, the current position of the cam may be clearly

determined. Therefore, it is possible to precisely control the state of the

latch module (the manual lock, the automatic opening, and the secure lock)

89932573.1 by controlling the drive and the cam.

[263] However, as a result of the determination, if the cam is in the fourth mode

state where none of the switches are pressed, it is not possible to clearly

determine the current position of the cam. For example, referring to FIG.

14, all the remaining ranges except for the first mode M1, the second mode

M2 and the third mode M3 shown are the fourth mode M4.

[264] According to the embodiment, when a current state of the cam and the latch

cannot be determined in the initial operation of the cooking device, the

position is initialized, which may be a position search and an initial position

setting operations.

[265] When the cam is in the fourth mode, with respect to searching the position

and setting the initial position, the initial position may be searched by

rotating the cam in any one direction and determining an initially pressed

switch. For example, when the cam and the latch are positioned where the

cam in the fourth mode, the cam is rotated in any direction to reach any one

of the first mode M1, the second mode M2 and the third mode M3.

[266] However, according to the embodiment, as the latch module 4 is

incorporated with an automatic opening function of the door, there is a

problem that the door may be automatically opened when the controller 80

reaches the second mode M2 while searching for the initial position of the

cam 70. That is, the cam should not reach the second mode M2 during the

rotation of the cam while determining the initial position of the cam.

89932573.1

[267] Thus, according to the embodiment, the switches 81 and 82 are arranged

so that the buttons 811 and 812 have a predetermined angle b so that the

buttons 811 and 812 are not arranged on a straight line on the center of

rotation of the cam, and the cam has a switch pressing profile 72 having

two pressing bosses 721 and 722 having an angle corresponding thereto,

and the bidirectional rotational motor 60 is used as the drive 60.

[268] The motor 60 is driven in the first rotational direction c I to switch the cam

70 to the second mode M2 when the automatic opening function is

performed based on the first mode M1 in the manual lock state, and the

motor 60 is driven again in the second rotational direction c I to be returned

to the first mode M1.

[269] Further, the motor 60 is driven in the second rotational direction cl to

switch the cam to the third mode M3 when the secure lock function is

performed based on the first mode M1 in the manual locked state, and the

motor 60 is driven again in the first rotational direction c2 to be returned to

the first mode M1.

[270] According to the above-described control method, the position of the latch

position adjusting profile 73 in contact with the contact surface of the latch

50 is only within a contact range R of FIG. 14. Based on this principle,

According to the embodiment, in an initial operation of the cooking device,

assuming the position of the cam 70 is in the fourth mode in which the two

switches are not pressed, the cam 70 is rotated in the second rotational

89932573.1 direction c2 in order to determine the initial positions of the cam 70 and the latch 50.

[271] When the cam 70 is in the fourth mode in the normal operation range R,

the position of the cam 70 in contact with the latch 50 is between the third

mode and the first mode of FIG. 14 (between about 1200 and 240), and

between the first mode and the second mode (about 260° to 370 (100)).

Therefore, when the cam 70 is rotated in the second rotational direction c2,

the cam 70 reaches the third mode or reaches the first mode, but does not

reach the second mode. Therefore, when the cam 70 is rotated in the second

rotational direction c2, the door does not in the initial position search step.

[272] Geometrically, a position range in which the cam 70 does not press both

the switches are three cases, for example, a first case in which the second

pressing boss 722 is within the angle of the two switches as shown in FIG.

15, a second case in which the first pressing boss 721 is within the angle of

the two switches as shown in FIG. 16, and a third case in which the two

pressing bosses 721 and 722 deviate from the angle of the two switches as

shown in FIG. 17.

[273] Among these cases, the state as shown in FIG. 15 may be between the third

mode and the first mode (between about 1200 to 2400) of FIG. 14. the state

as shown in FIG. 16 may be the case where the cam is in the first mode and

89932573.1 the second mode {about 2600 to 370 (10°)}.

[274] Specifically, if the cam was initially in the position shown in FIG. 15, the

cam reaches the first mode M1 after the cam is rotated in the second

rotational direction c2 for searching the initial position of the cam. The

controller 80 stops driving the motor 60 when the two switches 81, 82 are

pressed. The cam 70 and the latch 50 are disposed in the manual locked

state.

[275] If the cam 70 is initially in the position shown in FIG. 16, the cam 70

reaches the third mode M3 after the cam is rotated in the second rotational

direction c2 for searching the initial position of the cam. As the third mode

is the secure lock position, the door is not automatically opened. When the

second switch 82 is pressed and the first switch 81 is not pressed, the

controller drives the motor 60 again in the opposite direction to rotate the

cam in the first rotational direction cl. The cam reaches the first mode M1.

The controller stops driving the motor 60 when both switches 81, 82 are

pressed. The cam and latch may be in the manually locked position.

[276] That is, within a normal operating range R, case 1 and case 2 as shown in

FIG. 18 are provided as an example of searching an initial position of the

cam 70. Therefore, the door may not be automatically opened during search

of the cam 70 with respect to the initial position.

[277] However, it may not exclude that the position of the cam 70 is in the state

89932573.1 shown in FIG. 17. For example, the initial position of the cam during manufacturing of the latch module 4 may be in the state as shown in FIG.

17. According to the embodiment, the controller 80 causes the cam 70 to

rotate in the second rotational direction c2 when the cam is in the fourth

mode during the initial driving of the cooking device. If the cam rotates in

the second rotational direction c2 and reaches the second mode M2, that is,

if the first switch 81 is only pressed and the second switch 82 is not pressed,

the cam is further rotated in the second rotational direction c2 as shown in

case 3 in FIG. 18. As a result, the cam enters the first mode M1. The

controller stops the driving the motor 60 when both switches 81, 82 are

pressed. The cam and latch may be in the manually locked position.

[278] In such a state, the door may be opened. However, when the power is

supplied to the latch module 4 before the latch module 4 is installed in the

cooking device during the manufacturing of the product, the cam 70 and

the latch 50 become the first mode M1 through the initial search step as

described above. Further, during the manufacturing of the product, when

the latch module 4 is installed in the cooking device and the power is

supplied to the cooking device for inspection of the cooking device, the

above-described initial search step is performed and the cam and the latch

are in the first mode M1. Therefore, when the consumer purchases the

cooking device and first uses the cooking device, the cam may not be in

the state as shown in FIG. 17.

89932573.1

[279] As described above, the controller 80 may control the position of the latch

50 by controlling the rotational displacement of the cam 70 through the

switches 81 and 82 and the motor 60. In other words, the controller 80 may

control such that the position of the latch 50 is at least one of the first basic

position, the second basic position (the automatic opening position) and the

third basic position (the secure lock position). Further, as described above,

the control as shown in FIG. 18 may also be possible through the controller

80.

[280] While the present disclosure has been described with reference to

exemplary embodiments thereof, it is to be understood that the disclosure

is not limited to the disclosed embodiments and drawings, and it will be

apparent that various modifications may be made by those skilled in the art

within the range of the technical idea of the present disclosure. For example,

in the embodiment of the present disclosure, a structure in which a cam is

applied as a power transmitting portion is exemplified, but a power

transmission structure that adjusts a basic position of the latch is

implemented through a combination of various other kinematic structures

such as a long hole, a hinge, and a link, and the like.

[281] While the present disclosure does not explicitly describe the working

effects based on the configuration of the present disclosure in the

description of the embodiments of the present disclosure, it is to be noted

that the expectable effects are acknowledged based on the configuration.

89932573.1

Claims

WHAT IS CLAIMED IS:

1. A cooking appliance comprising:

a main body (10) having a cavity, wherein the main body is provided with a

latch (50), and positions to which the latch can move include a first basic position, a

second basic position moved in a second direction (w2) from the first basic position,

and a third basic position moved in the first direction (wl) from the first basic position;

a door (20) for opening and closing an open front of the cavity, wherein the

door (20) is provided with an engaging structure (22), the engaging structure (22)

engages the latch (50) when the latch (50) is in the first basic position and third basic

positions, and the engaging structure (22) does not engage the latch (50) when the latch

(50) is in the second basic position; and

a controller (80) for controlling the opening and closing of the door (20),

wherein the controller (80) controls the movement of the latch 50 to the first basic

position, the second basic position, and the third basic position.

2. The cooking appliance of claim 1, further comprising a hinge module

(300) that rotatably connects the door (20) about the main body (10),

wherein the hinge module (300) applies a force to the door (20) in an opening

direction of the door (20) when the door is closed and opens the door (20) when the

latch (50) is in the second basic position.

3. The cooking appliance of claim 1, wherein the first basic position is a

position in which the latch (50) is released from the engaging structure (22) and the

89932573.1 door (20) can be opened when an external force is applied to the door (20) in a direction in which the door (20) is opened, and the third basic position is a position in which the latch (50) maintains a locked state with the engaging structure (22) even when an external force is applied to the door (20) in the direction in which the door (20) is opened.

4. The cooking appliance of claim 1, wherein the latch (50) includes a hook

(51) for engaging with the engaging structure (22),

wherein the hook is opened toward the first direction,

wherein an engaging surface (52) is provided in the hook, the engaging surface

(52) is engaged with a rear surface of the engaging structure (22),

wherein the engaging surface (52) includes a disengaging inclined surface

(521) disposed closer to a distal end of the hook, and a secure lock surface (522)

disposed farther from the distal end of the hook than the disengaging inclined surface

(521),

wherein the disengaging inclined surface (521) has a first inclined surface,

wherein secure lock surface (522) has a second inclined surface, and the

inclination angles of the first and second inclined surface are different from each other,

wherein the engaging structure (22) contacts the disengaged inclined surface

(521) when the latch (50) is in the first basic position, and

wherein the engaging structure (22) contacts the secure lock surface (522)

when the latch (50) is in the third basic position.

89932573.1

5. The cooking appliance of claim 1, further comprising:

an elastic body (90) configured to apply the force to move the latch (50) in the

first direction (wl);

a drive (60) configured to provide power to move the latch (50) in the second

direction (w2) and controlled by the controller (80); and

a cam (70) configured to transmit the power of the drive (60) to the latch (50),

wherein the cam comprises a latch position adjusting profile (73) that contacts

the latch, the latch position adjusting profile (73) includes in a circumferential

direction at the outer circumference thereof:

a first radius (731) that has a radius such that the latch (50) is disposed in

the first basic position when the first radius of the cam contacts the contact surface of

the latch (50),

a second radius (732) that has a radius such that the latch (50) is disposed

in the second basic position when the second radius of the cam contacts the contact

surface of the latch (50), and

a third radius (733) that has a radius such that the latch (50) is disposed

in the third basic position when the third radius of the cam contacts the contact surface

of the latch (50).

6. The cooking appliance of claim 1, wherein the cam (70) further comprises

a switch pressing profile (72),

89932573.1 wherein the cooking appliance further comprises a switch that is pressed or depressed by the switch pressing profile (72), the switch is connected to the controller

(80),

wherein the switch comprises a first switch (81) and a second switch (82),

wherein, by the switch pressing profile (72), the cam (70) becomes one of a first

mode in which the first switch (81) and the second switch (82) are pressed, a second

mode in which the first switch (81) is pressed and the second switch (82) is not pressed,

a third mode in which the second switch (82) is pressed and the first switch (81) is not

pressed, and a fourth mode in which the first switch (81) and the second switch (82)

are not pressed,

wherein the latch (50) is in the first basic position while the cam (70) contacts the

latch (50) when the switch pressing profile (72) is in a first selection mode of the first

to fourth modes as the cam (70) rotates,

wherein the latch (50) is in the second basic position while the cam contacts the

latch (50) when the switch pressing profile (72) is in a second selection mode of the

first to fourth modes as the cam (70) rotates, and

wherein the latch (50) is in the third basic position while the cam contacts the latch

(50) when the switch pressing profile (72) is in a third selection mode of the first to

fourth modes as the cam (70) rotates.

7. A latch module for controlling an opening and a closing of a door (20) of a

cooking appliance including a main body (10) having a cavity and the door (20) that

opens and closes an open front of the cavity, comprising:

89932573.1 a latch (50); an elastic body (90) that applies an elastic force to the latch (50); a drive (60) that provides power for the latch (50) to move; and a cam (70) that contacts a contact surface (55) of the latch (50) and transmits the power of the drive (60) to the latch (50), wherein the latch (50) further comprises an extension (58) having a sub-contact surface (59) that approaches a surface of the cam (70) or is away from a surface of the cam (70) as the latch (50) moves.

8. The latch module of claim 7, wherein the elastic force of the elastic body

(90) is applied so that the latch (50) moves in a first direction (wl),

the power of the drive (60) is applied through the contact surface (55) of the latch

(50) so that the latch (50) moves in a second direction (w2),

the second direction (w2) is opposite to the first direction (wl),

and the power of the drive (60) is applied through the sub-contact surface (59) of

the latch (50) so that the latch (50) moves in the first direction (wl).

9. The latch module of claim 7, wherein the cam (70) has a first radius (731),

a second radius (732), and a third radius (733) in a circumferential direction at the

outer circumference thereof,

wherein the first radius (731) has such a radius that the latch (50) is disposed in a

first basic position, when the first radius (731) contacts the side of the latch (50),

89932573.1 wherein the second radius (732) has a radius greater than the first radius (731) to further move the latch (50) in the second direction than the first basic position when the second radius (732) contacts the side of the latch (50) so that the latch (50) is disposed in a second basic position in which the latch (50) is released from the door

(20),

wherein the third radius (733) has a radius less than the radius of the first radius

(731) to allow the latch (50) to further move in the first direction than the first basic

position when the third radius (733) contacts the side of the latch (50) so that the latch

(50) is disposed in a third basic position in which the latch (50) securely locks the door

(20).

Wherein, when the first radius (731) of the cam is in contact with the contact

surface (55) of the latch (50), a cam surface facing the sub-contact surface (59) has a

radius (rM1) that allows the sub-contact surface (59) to approach the cam surface even

when the latch (50) is moved from the first basic position to the second basic position.

10. The latch module of claim 9, wherein a radius (rM3) of the cam surface

facing the sub-contact surface (59) when the third radius (733) of the cam (70) is in

contact with the contact surface (55) of the latch (50) is greater than a distance (dmp)

between a position (mp) of the sub-contact surface (59) and the center of rotation (711)

of the cam (70) when the latch (50) is in thefirst basic position.

89932573.1