Capacitive sensor system

• US 8,049,518 B2
• Filed: 09/13/2005
• Issued: 11/01/2011
• Est. Priority Date: 09/17/2004
• Status: Active Grant

• Current Assignee: Electrolux Home Products Corporation NV (AB Electrolux)
• Original Assignee: Electrolux Home Products Corporation NV (AB Electrolux)
• Inventors: Johansson, Jan, Wern, Lars-Ake
• Primary Examiner(s): Koval; Melissa
• Assistant Examiner(s): Hoque; Farhana
• Application Number:
  US11/575,327
• Publication Number:
  US 20080204047A1
• Time in Patent Office: 2,240 Days
• Field of Search: 324/600, 324658-690, 327/517, 621/25
• US Class Current: 324/661
• CPC Class Codes: E05F 15/46 responsive to changes in electrical capacitance
• CPC Class Codes: E05Y 2900/31 for refrigerators
• CPC Class Codes: F25D 23/028 Details
• CPC Class Codes: F25D 2700/02 Sensors detecting door opening
• CPC Class Codes: F25D 2700/04 Sensors detecting the presence of a person
• CPC Class Codes: F25D 29/00 Arrangement or mounting of control or safety devices
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/975 using a capacitive movable element

Abstract

The present invention relates to a capacitive sensor system provided for a moving object 21.The system comprises an antenna device with a first 26 and a second portion 39 which are movable in relation to each other, the two portions 26,39 being connected in parallel for capacitive influence from the surroundings. The first portion 26 constitutes in an electrical conductive part of said moving object 21 and the second section 39 constitutes in an electrical conductive device arranged at a rest position for the moving object 21.

Claims

1. Capacitive sensor system provided for a door (21) of a refrigeration appliance, the capacitive sensor system being arranged for detecting properties of a capacitance (42) between an antenna device and an earth plane (23), wherein the antenna device comprises a first (26) and a second portion (39) which are movable in relation to each other, the second portion (39) being connected to and electrically parallel with the first portion (26), and the two portions being arranged in parallel in relation to said capacitance (42) for capacitive influence from a small portion of a human body, wherein the first portion (26) being an electrical conductive door part of said door (21), the electrical conductive door part being a liner forming said door, and the second portion (39) being an electrical conductive device arranged at a rest position for the door (21), wherein said door is arranged to close at least one compartment opening of the appliance.

2. Capacitive sensor system according to claim 1 wherein the door (21) is provided with an electrically operable unit (25), whereby the sensor system is provided with a operating device (46) arranged to operate the operable unit (25) and said electrical conductive device (39) being positioned at the periphery of the compartment opening.

3. Capacitive sensor system according to claim 2 wherein said electrically operable unit (25) being arranged to move the door (21), the operable unit (25) being operated depending on the influence of the small portion of a human body through a capacitance formed between the antenna device and said earth plane (23) for said antenna device, the antenna device being electrically insulated from the earth plane.

4. Capacitive sensor system according to claim 3 wherein said capacitive sensor system is integrated into the door (21) and has a signal input (59) connected to said earth plane (23) and a signal ground (36) connected to the electrically conductive door part (26), whereby all components connected to the sensor system will be a part of said antenna device.

5. Capacitive sensor system provided for a door (21), the capacitive sensor system being arranged for detecting properties of a capacitance (42) between an antenna device and an earth plane (23), wherein the antenna device comprises a first (26) and a second portion (39) which are movable in relation to each other, the second portion (39) being connected to and electrically parallel with the first portion (26), and the two portions being arranged in parallel in relation to said capacitance (42) for capacitive influence from a small portion of a human body, wherein the first portion (26) being an electrical conductive door part of said door (21) and the second portion (39) being an electrical conductive device arranged at a rest position for the door (21),

wherein the door (21) is provided with an electrically operable unit (25) and in said rest position is arranged to close a passage, whereby the sensor system is provided with a operating device (46) arranged to operate the operable unit (25) and said electrical conductive device (39) being positioned at the periphery of the passage,

wherein said electrically operable unit (25) being arranged to move the door (21), the operable unit (25) being operated depending on the influence of the small portion of a human body through a capacitance formed between the antenna device and said earth plane (23) for said antenna device, the antenna device being electrically insulated from the earth plane,

wherein said capacitive sensor system is integrated into the door (21) and has a signal input (59) connected to said earth plane (23) and a signal ground (36) connected to the electrically conductive door part (26), whereby all components connected to the sensor system will be a part of said antenna device, and wherein said electrically operable unit (25) is integrated into the door (21) and is arranged to be a part of the electrical conductive door part (26), whereby the operable unit (25) will be an operational part of said first antenna.