Latch device for a door of an electric household appliance in particular a dishwashing machine

• US 7,347,460 B2
• Filed: 07/28/2005
• Issued: 03/25/2008
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: ITW Industrial Components s.r.l. (Illinois Tool Works Inc.)
• Original Assignee: ITW Industrial Components s.r.l. (Illinois Tool Works Inc.)
• Inventors: Ala, Gian Battista
• Primary Examiner(s): ESTREMSKY, GARY WAYNE
• Application Number:
  US11/190,891
• Publication Number:
  US 20060033346A1
• Time in Patent Office: 971 Days
• Field of Search: 292/216, 292/DIG.56, 292/111, 292/312, 292/31.A, 292/DIG.37
• US Class Current: 292/216
• CPC Class Codes: A47L 15/4259 Arrangements of locking or security/safety devices for doors, e.g. door latches, switch to stop operation when door is open
• CPC Class Codes: E05B 1/0038 Sliding handles, e.g. push buttons E05B13/105 takes precedence
• CPC Class Codes: E05C 3/24 in the form of a bifurcated member automatic catches with a bifurcated latch E05C19/024; locks with a bifurcated bolt E05B65/0046, E05B85/243
• CPC Class Codes: Y10S 292/37 Push button operators
• CPC Class Codes: Y10T 292/1047 Closure

Abstract

A latch device for a swing door of an electric household appliance, includes a support fixable to the door; a fork-shaped latch member fitted in rotary manner to the support to cooperate, in use, with a fixed striker of the appliance; and a control button fitted to the support to slide in opposition to a first elastic element. The latch member is movable, in opposition to a second elastic element on the support, between a first operating position, in which it does not engage the striker, and a second operating position, in which it does engage the striker. A contact member is fitted to the support to slide parallel to the control button in opposition to a third elastic element, and operatively interposed between the control button and the latch member to selectively lock the latch member in the second operating position, and to be selectively locked by the latch member when the latch member is in the first operating position.

Claims

1. A latch device for a door of an appliance, said latch device comprising:

a support fixable to the door;

a latch member rotatably attached to the support and adapted to cooperate, in use, with a fixed striker fitted to a casing of the appliance; and

a control button moveably supported by the support and adapted to be positioned, in use, at a front surface of the door;

the latch member being rotatable between a unlatched position, in which the latch member is not latchable with the striker, and a latched position, in which the latch member is latchable with the striker;

the device further comprising

a contact member attached to the support to be moveable between first and second positions, and operatively interposed between the control button and the latch member to selectively lock the latch member when the latch member is in the latched position and the contact member is in the first position, and to be selectively locked by the latch member when the latch member is in the unlatched position and the contact member is in the second position;

wherein

when said latch member is in the latched position and said contact member is in the first position, said contact member engages said latch member, prevents said latch member from moving to the unlatched position, and is moveable by a movement of said control button to the second position in which said contact member disengages said latch member and allows said latch member to be moveable to the unlatched position; and

when said latch member is in the unlatched position and said contact member is in the second position, said latch member engages said contact member, prevents said contact member from moving to the first position, and is moveable to the latched position in which said latch member disengages said contact member and allows said contact member to be moveable to the first position;

said device further comprising an electric control element for controlling the appliance, said electric control element being attached to the support and adapted to be activated by the contact member;

wherein the contact member, in the first position, rests against a rear end of said control button and does not activate the electric control element, and, in the second position, activates the electric control element; and

wherein said latch member and said contact member have first and second pairs of corresponding contact elements, which are respectively engageable to lock said latch member selectively in said latched position when said contact member is in said first position, and lock said contact member selectively in said second position when said latch member is in said unlatched position.

2. A device as claimed in claim 1, wherein said electric control element comprises a normally-closed microswitch.

3. A device as claimed in claim 1, wherein said first pair of corresponding contact elements comprise

a first contact surface located on the latch member and projecting substantially radially with respect to a fulcrum of the latch member;

and

a second contact surface located on the contact member, extending substantially parallel to a path along which the contact member is moveable between the first and second positions, and lying substantially in a plane through said fulcrum of the latch member.

4. A device as claimed in claim 3, wherein said second pair of corresponding contact elements comprise

a third contact surface located on the outer circumference of the latch member, on the opposite side to the control button;

and

a fourth contact surface located on the contact member, adjacent to said second contact surface, and extending crosswise to the path of the contact member.

5. A device as claimed in claim 4, wherein said first contact surface and said third contact surface are formed on a radial projection of said latch member.

6. A latch device for a door of an electric household appliance, said device comprising:

a support fixable to the door;

a fork-shaped latch member fitted in rotary manner to the support in such a position as to cooperate, in use, with a fixed striker fitted to a casing of the appliance; and

a control button fitted to the support to be slidable in opposition to a first elastic element, so as to be positioned, in use, at a front surface of the door;

the latch member being movable, in opposition to a second elastic element on the support, between a first operating position, in which said latch member does not engage the striker, and a second operating position, in which said latch member does engage the striker;

wherein

the device further comprises;

a contact member fitted to the support to be slidable parallel to the control button, and operatively interposed between the control button and the latch member to selectively lock the latch member in the second operating position, and to be selectively locked by the latch member when the latch member is in the first operating position; and

an electric control element for controlling the appliance, said electric control element being fitted to the support and adapted to be activated by the contact member;

the contact member is movable, in opposition to a third elastic element, between a first position, in which said contact member rests against a rear end of said control button and does not activate the electric control element, and a second position, in which said contact member does activate the electric control element; and

said contact member is housed in a seat inside the support, between said control button and said electric control element, slidable on a bottom wall of the seat, and positioned facing an opening of the seat, where a fulcrum of said latch member is located.

7. A device as claimed in claim 6, wherein on the opposite side to the control button and at said opening, said support has a protection member for protecting the latch member and having an opening through which said striker is received in use.

8. A latch device for a door of an appliance, said latch device comprising:

a support fixable to the door;

a latch member rotatably attached to the support and adapted to cooperate, in use, with a fixed striker fitted to a casing of the appliance; and

a control button moveably supported by the support and adapted to be positioned, in use, at a front surface of the door;

the latch member being rotatable between a unlatched position, in which the latch member is not latchable with the striker, and a latched position, in which the latch member is latchable with the striker;

the device further comprising

a contact member attached to the support to be moveable between first and second positions, and operatively interposed between the control button and the latch member to selectively lock the latch member when the latch member is in the latched position and the contact member is in the first position, and to be selectively locked by the latch member when the latch member is in the unlatched position and the contact member is in the second position;

wherein

when said latch member is in the latched position and said contact member is in the first position, said contact member engages said latch member, prevents said latch member from moving to the unlatched position, and is moveable by a movement of said control button to the second position in which said contact member disengages said latch member and allows said latch member to be moveable to the unlatched position; and

when said latch member is in the unlatched position and said contact member is in the second position, said latch member engages said contact member, prevents said contact member from moving to the first position, and is moveable to the latched position in which said latch member disengages said contact member and allows said contact member to be moveable to the first position;

said device further comprising;

a first elastic element biasing said latch member towards the unlatched position;

a second elastic element biasing said contact member towards the first position; and

a third elastic element biasing said control button away from said contact member.

9. A device as claimed in claim 8, further comprising an electric control element for controlling the appliance, said electric control element being attached to the support and adapted to be activated by the contact member;

in the first position, the contact member rests under biasing forces of said second elastic element against a rear end of said control button and does not activate the electric control element, and,

in the second position, the contact member activates the electric control element.

10. A device as claimed in claim 9, wherein said electric control element comprises a normally-closed microswitch.

11. A device as claimed in claim 9, wherein said latch member and said contact member have first and second pairs of corresponding contact elements, which are respectively engageable to lock said latch member selectively in said latched position when said contact member is in said first position, and lock said contact member selectively in said second position when said latch member is in said unlatched position.

12. A device as claimed in claim 11, wherein said first pair of corresponding contact elements comprise

a first contact surface located on the latch member and projecting substantially radially with respect to a fulcrum of the latch member;

and

a second contact surface located on the contact member, extending substantially parallel to a path along which the contact member is moveable between the first and second positions, and lying substantially in a plane through said fulcrum of the latch member.

13. A device as claimed in claim 12, wherein said second pair of corresponding contact elements comprise

a third contact surface located on the outer circumference of the latch member, on the opposite side to the control button;

and

a fourth contact surface located on the contact member, adjacent to said second contact surface, and extending crosswise to the path of the contact member.

14. A device as claimed in claim 13, wherein said first contact surface and said third contact surface are formed on a radial projection of said latch member.

15. A latch device for a door of an appliance, said latch device comprising:

a support fixable to the door;

a latch member rotatably attached to the support and adapted to cooperate, in use, with a fixed striker fitted to a casing of the appliance; and

a control button moveably supported by the support and adapted to be positioned, in use, at a front surface of the door;

the latch member being rotatable between a unlatched position, in which the latch member is not latchable with the striker, and a latched position, in which the latch member is latchable with the striker;

the device further comprising

a contact member attached to the support to be moveable between first and second positions, and operatively interposed between the control button and the latch member to selectively lock the latch member when the latch member is in the latched position and the contact member is in the first position, and to be selectively locked by the latch member when the latch member is in the unlatched position and the contact member is in the second position;

wherein

when said latch member is in the latched position and said contact member is in the first position, said contact member engages said latch member, prevents said latch member from moving to the unlatched position, and is moveable by a movement of said control button to the second position in which said contact member disengages said latch member and allows said latch member to be moveable to the unlatched position; and

when said latch member is in the unlatched position and said contact member is in the second position, said latch member engages said contact member, prevents said contact member from moving to the first position, and is moveable to the latched position in which said latch member disengages said contact member and allows said contact member to be moveable to the first position;

said contact member is housed in a seat inside the support, between said control button and said electric control element, slidable on a bottom wall of the seat, and positioned facing an opening of the seat, where a fulcrum of said latch member is located.

16. A device as claimed in claim 15, wherein on the opposite side to the control button and at said opening, said support has a protection member for protecting the latch member and having an opening though which said striker is received in use.