Washing machine lid lock with magnetic lid sensor

• US 20060288742A1
• Filed: 08/31/2006
• Published: 12/28/2006
• Est. Priority Date: 01/14/2003
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: ARK-LES Corporation (Illinois Tool Works Inc.)
• Inventors: Hapke, Kenyon A., Osvatic, Michael
• Granted Patent: US 7,493,783 B2
• Time in Patent Office: Days
• US Class Current: 68/12.260
• CPC Class Codes: D06F 34/20 Parameters relating to constructional components, e.g. door sensors
• CPC Class Codes: D06F 37/42 Safety arrangements, e.g. for stopping rotation of the receptacle upon opening of the casing door
• CPC Class Codes: D06F 39/14 Doors or covers; Securing means therefor

Abstract

A magnetic lid closure sensor uses a magnet sensor element mounted within the washing machine housing below the closed lid. Flux directors conduct flux from a magnet in the lid to the magnet sensor. A lock mechanism employs a hook engaging an aperture in the lid so that opening of the lid does not impart a torque to the hook such as would disengage it, allowing the hook to be activated and deactivated with a simple bi-directional solenoid.

Claims

1. A magnetic lid sensor for a washing machine lid supporting a magnet, the sensor comprising:

a sensor housing mountable on the washing machine;

a magnet sensor held within the sensor housing adapted to be displaced from a point of rest of the magnet when the washing machine lid is closed and the sensor housing is mounted on the washing machine; and

at least one ferromagnetic flux director held by the sensor housing and having a first end positionable near the point of rest of the magnet and a second end held near the magnetic sensor to conduct flux between the magnet and magnet sensor when the sensor housing is mounted on the washing machine.

2. The magnetic lid sensor of claim 1 wherein the sensor housing is a non-magnetic material.

3. The magnetic lid sensor of claim 1 wherein the magnet sensor is a reed switch.

4. The magnetic lid sensor of claim 1 including two ferromagnetic flux directors each having first and second ends positioned with their first ends flanking the magnet and their second ends flanking the magnet sensor to conduct magnetic flux in a loop between the magnet sensor and the magnet.

5. The magnetic lid sensor of claim 1 further including:

a cap sized to cover a hole in the housing of a washing machine near a point of rest of the washing machine lid when the washing machine lid is closed, the cap including at least one downwardly extending bore;

wherein the sensor housing has at least one mounting hole conducting a shaft of an upwardly extending screw receivable within the downwardly extending hole of the cap to compress the washing machine housing between an upper surface of the sensor housing and a lower surface of the cap when the screw is tightened

6. The magnetic lid sensor of claim 5 wherein the sensor housing further supports a hook pivotable about an axis at a pivot point proximate to the mounting hole, the hook pivoting between a first position in which opening of the closed washing machine lid is prevented by interference between the hook and an engagement surface on the washing machine lid, and a second position in which the closed washing machine lid is free to open.

7. The lid lock assembly of claim 5 wherein the downwardly extending bore is blind to present a continuous upper cap surface.

8. The lid lock assembly of claim 5 wherein the cap includes only a single downwardly extending bore and the sensor housing includes only a single mounting hole for attaching the lock housing to the washing machine.

9. The lid lock assembly of claim 5 wherein the cap is an elastomeric plastic over a non-elastomeric plastic base, the latter supporting the bore.