Appliance switching mechanism and method

• US 6,350,970 B1
• Filed: 05/07/1999
• Issued: 02/26/2002
• Est. Priority Date: 05/07/1999
• Status: Expired due to Fees

• Current Assignee: Salton Incorporated (Spectrum Brands Holdings, Inc.)
• Original Assignee: Salton Incorporated (Spectrum Brands Holdings, Inc.)
• Inventors: Huggler, Peter
• Primary Examiner(s): Jeffery, John A.
• Application Number:
  US09/307,080
• Time in Patent Office: 1,026 Days
• Field of Search: 219/514, 219/519, 219/521, 219/385, 993/27, 993/91--92, 993/93, 993/99, 993/38, 200/1.TK, 200/1.A, 200/DIG.46, 200/283, 200/245-247, 200/238
• US Class Current: 219/514
• CPC Class Codes: A47J 37/0842 with electronic timers

Abstract

A switching mechanism is utilized in a heating appliance, such as a toaster, that includes a bread support that supports a food item to insert and remove the food item from a cooking cavity of the appliance. The appliance includes an electronic circuit that controls operation during a heating cycle. The switching mechanism includes a switch having a first terminal adapted to receive a power signal and a second terminal coupled to the electronic circuit. The switch operates responsive to an applied switching force to couple the first terminal to the second terminal and thereby apply power to the electronic circuit. A switch actuator has a first end, a second end, and a retaining member near the second end. The second end is attached to the appliance to rotate about an axis. The switch actuator operates responsive to a force being applied to the bread support to rotate about the axis to a first position and apply the switching force to the switch so power is applied to the electronic circuit. A retaining force is applied to the first end of the actuator to secure the actuator in the first position responsive to power being applied to the electronic circuit and the retaining member engages the bread support to hold the bread support with the food item positioned in the cooking cavity when the actuator is in the first position. The switch actuator operates responsive to the retaining force being removed to rotate about the axis to remove the switching force and thereby remove power from the electronic circuit to terminate the heating cycle. Various other aspects of the present invention are directed, for example, to contacts formed on a printed circuit board and switch blades formed separate from the printed circuit board, heat-staking of the switch blades, and crimp details on the switch blades that eliminates the need for wire terminals.

Claims

1. A switching mechanism for a heating appliance including a bread support that is adapted to support a food item to insert and remove the food item from a cooking cavity of the appliance, and the appliance including an electronic circuit that controls operation during a heating cycle, the switching mechanism comprising:

a switch having a first terminal adapted to receive a power signal and a second terminal coupled to a component of the heating appliance, the switch operable responsive to an applied switching force to couple the first terminal to the second terminal;

a switch actuator having a first end, a second end, and a retaining member spaced apart from the first end, the second end being attached to the appliance to rotate about an axis, the switch actuator operable responsive to a force being applied to the bread support to rotate about the axis to a first position and apply the switching force to the switch so power is applied to the component of the heating appliance, the retaining member engaging the bread support to maintain the bread support in a lowered position in the cooking cavity when the actuator is in the first position; and

a retaining mechanism applying a retaining force to the first end of the switch actuator to secure the switch actuator in the first position responsive to power being applied to the component of the heating appliance, the retaining mechanism removing the retaining force at the end of the heating cycle to allow the switch actuator to rotate about the axis to remove the switching force and thereby remove power from the component of the heating appliance.

2. The switching mechanism of claim 1 wherein the component of the heating appliance to which power is applied through the switch comprises heating elements of the heating appliance.

3. The switching mechanism of claim 1 wherein the component of the heating appliance to which power is applied through the switch comprises the electronic circuit.

4. The switching mechanism of claim 1 wherein the switch actuator further comprises a metallic keeper mounted on the first end of the actuator, and the retaining mechanism comprises an electromagnet that generates an electromagnetic force applied to the metallic keeper to hold the switch actuator in the first position.

5. The switching mechanism of claim 1 wherein the switch comprises a resilient blade and a contact coupled to the component of the heating appliance, the switch actuator applying the switching force to the resilient blade so the resilient blade touches the contact when in the first position, and the resilient blade applying a return force causing the switch actuator to rotate the axis so the resilient blade is isolated from the contact when the retaining force is removed.

6. The switching mechanism of claim 1 wherein the switch actuator comprises:

an approximately U-shaped member including two radially extending members each having an end attached to rotate about the axis, and the U-shaped member including a base member formed between the radially extending members opposite the ends attached to rotate about the axis;

a retaining member connected to the base portion near one of the radially extending members, the retaining member including a surface operable to engage a portion of the bread support;

a lever member having first and second ends, the second end being connected to the base of the U-shaped member; and

a keeper connected near the first end of the lever member.

7. The switching mechanism of claim 6 wherein the members of the switch actuator are integrally formed to form the switch actuator.

8. The switching mechanism of claim 1 wherein the bread support directly engages the switch actuator responsive to the force being applied to the bread support thereby rotating the switch actuator to the first position.

9. A switching mechanism for a heating appliance including a bread support that supports a food item to insert and remove the food item from a cooking cavity of the appliance, the switching mechanism comprising:

a switch comprising;

first and second contacts mounted on a printed circuit board, each contact being electrically coupled to apply a corresponding voltage to an electronic circuit formed on the printed circuit board, and the electronic circuit controlling operation of the appliance;

first and second resilient blades adapted to receive respective power signals, each of the resilient blades having a first end attached to a mounting structure that is attached to the appliance, and each of the first and second blades having a second end extending over the first and second contacts, respectively, each of the resilient blades operable responsive to an applied force to bend and touch its second end to the corresponding contact;

a switch actuator having a first end, a second end, and a retaining member near the second end, the second end being attached to the appliance to rotate about an axis, and the switch actuator operable responsive to a force being applied to the bread support to rotate about the axis to a first position and apply the switching force to the resilient blades so power is applied to the electronic circuit, the retaining member engaging the bread support to hold the bread support in a lowered positioned in the cooking cavity when the switch actuator is in the first position; and

a retaining mechanism applying a retaining force to the first end of the switch actuator to secure the switch actuator in the first position responsive to power being applied to the electronic circuit, the retaining mechanism removing the retaining force from the first end of the switch actuator at the end of the heating cycle to allow the switch actuator to rotate about the axis to remove the switching force and thereby remove power from the electronic circuit.

10. The switching mechanism of claim 9 wherein the switch actuator further comprises a metallic keeper mounted on the first end of the actuator, and the retaining mechanism comprises an electromagnet that generates an electromagnetic force applied to the metallic keeper to hold the switch actuator in the first position.

11. The switching mechanism of claim 9 wherein the switch comprises a resilient blade and a contact coupled to the electronic circuit, the switch actuator applying the switching force to the resilient blade so the resilient blade touches the contact when in the first position, and the resilient blade applying a return force causing the switch actuator to rotate about the axis so the resilient blade is isolated from the contact when the retaining force is removed.

12. The switching mechanism of claim 9 wherein the switch actuator comprises:

an approximately U-shaped member including two radially extending members each having an end attached to rotate about the axis, the U-shaped member including a base member formed between the radially extending members opposite the ends attached to rotate about the axis;

a retaining member connected to the base portion near one of the radially extending members, the retaining member including a surface operable to engage a portion of the bread support;

a lever member having first and second ends, the second end being connected to the base of the U-shaped member; and

a keeper connected near the first end of the lever member.

13. The switching mechanism of claim 12 wherein the members of the switch actuator are integrally formed to form the switch actuator.

14. The switching mechanism of claim 9 wherein the bread support indirectly engages the switch actuator responsive to the force being applied to the bread support thereby rotating the switch actuator to the first position.

15. A heating appliance, comprising:

a housing having a plurality of sides with a cooking cavity being defined within the sides;

a bread support that supports a food item, the bread support being contained within the cooking cavity and operable responsive to a first force to insert the food item into the cooking cavity and operable responsive to a second force to remove the food item from the cooking cavity;

a switching mechanism comprising;

a switch having first and second terminals, the switch operable responsive to an applied switching force to couple the first terminal to the second terminal to apply power to an electronic circuit that controls operation of the appliance;

a switch actuator having a first end, a second end, and a retaining member near the second end, and the second end being attached to the appliance to rotate about an axis, the switch actuator operable responsive to a force being applied to the bread support to rotate about the axis to a first position and apply the switching force to the switch so power is applied to the electronic circuit, the retaining member engaging the bread support to hold the bread support in a lowered position in the cooking cavity when the switch actuator is in the first position; and

a retaining mechanism applying a retaining force to the first end of the switch actuator to secure the switch actuator in the first position responsive to power being applied to the electronic circuit, the retaining mechanism removing the retaining force from the switch actuator at the end of the heating cycle to allow the switch actuator to rotate about the axis to remove the switching force and thereby remove power from the electronic circuit.

16. The heating appliance of claim 15 wherein the switch actuator further comprises a metallic keeper mounted on the first end of the actuator, and the retaining mechanism comprises an electromagnet that generates an electromagnetic force applied to the metallic keeper to hold the switch actuator in the first position.

17. The heating appliance of claim 15 wherein the switch comprises a resilient blade and a contact coupled to the electronic circuit, the switch actuator applying the switching force to the resilient blade so the resilient blade touches the contact when in the first position, the resilient blade applying a return force causing the switch actuator to rotate about the axis so the resilient blade is isolated from the contact when the retaining force is removed.

18. The heating appliance of claim 15 wherein the switch actuator comprises:

an approximately U-shaped member including two radially extending members each having an end attached to rotate about the axis, the U-shaped member including a base member formed between the radially extending members opposite the ends attached to rotate about the axis;

a retaining member connected to the base portion near one of the radially extending members, the retaining member including a surface operable to engage a portion of the bread support;

a lever member having first and second ends, the second end being connected to the base of the U-shaped member; and

a keeper connected near the first end of the lever member.

19. The heating appliance of claim 15 wherein the retaining member of the switch actuator is integrally formed with the switch actuator.

20. The heating appliance of claim 15 wherein the bread support indirectly engages the switch actuator responsive to the force being applied to the bread support thereby rotating the switch actuator to the first position.

21. The heating appliance of claim 15 wherein the heating appliance comprises a toaster.

22. A method for securing a bread support of a heating appliance in a desired position, the method comprising:

applying a force to the bread support to place the bread support in the desired position;

applying a retaining force through a lever arm to secure the bread support in the desired position when the lever arm is in a bread support retaining position;

using the lever arm to close a switch when the lever arm is in the bread support retaining position;

initiating a heating cycle responsive to the switch being closed;

removing the retaining force an end of the heating cycle to release the bread support at the end of a heating cycle.

23. The method of claim 22 wherein applying a retaining force comprises applying an electromagnetic force to secure the lever arm in the bread support retaining position and thereby secure the bread support in the desired position.

24. The method of claim 23, wherein the act of applying an electromagnetic force to secure the lever arm in the bread support retaining position comprises applying the electromagnetic force responsive to the switch being closed.

25. The method of claim 22 further comprising retaining the lever arm in its bread support retaining position responsive to the switch being closed.

26. A method for securing a bread support of heating appliance in a desired position, the heating appliance including a lever having first and second ends, the second end being attached to the appliance to rotate about an axis and the lever including a retaining portion formed near the second end and being adapted to hold the bread support in the desired position, the method comprising:

applying a force to the bread support to place the bread support in the desired position;

applying a force to the first end of the lever responsive to the bread support being placed in the desired position, the lever securing the bread support in the desired position when the force is applied;

initiating a heating cycle responsive to the lever being placed in a bread support retaining position in which it secures the bread support in the desired position, the lever being maintained in the bread support retaining position during the heating cycle; and

removing the force applied to the first end of the lever at the conclusion of the heating cycle so the lever releases the bread support.

27. The method of claim 26 wherein applying the force to the first end of the lever comprises generating an electromagnetic force that is applied to the first end of the bread support.

28. The method of claim 27, wherein the act of applying an electromagnetic force to secure the lever in the bread support retaining position comprises applying the electromagnetic force responsive to the initiation of the heating cycle.

29. The method of claim 26 further comprising retaining the lever arm in its bread support retaining position responsive to the heating cycle being initiated.