Capacitive toner level detection

• US 20020186027A1
• Filed: 06/07/2001
• Published: 12/12/2002
• Est. Priority Date: 06/07/2001
• Status: Active Grant

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Beehler, Todd C., Anthony, James D., Fournier, John C.
• Granted Patent: US 6,670,817 B2
• Time in Patent Office: Days
• US Class Current: 324/662
• CPC Class Codes: G03G 15/0856 Detection or control means for the developer level
• CPC Class Codes: G03G 15/086 the level being measured by electro-magnetic means
• CPC Class Codes: G03G 15/0881 Sealing of developer cartridges

Abstract

A container having an electrically conductive container body. The container body defines a container cavity. A sensor assembly is disposed within said container cavity. The sensor assembly is electrically isolated from the container body, and is configured for sensing a level of material within the container cavity.

Claims

1. A container, comprising:

an electrically conductive container body, said container body defining a container cavity; and

a sensor assembly disposed within said container cavity, said sensor assembly being electrically isolated from said container body, said sensor assembly configured for sensing a level of material within said container cavity.

2. The container of claim 1, wherein said sensor assembly comprises a capacitive sensor.

3. The container of claim 2, wherein said capacitive sensor comprises at least one first electrode plate and at least one second electrode plate spaced apart from a corresponding first electrode plate, each of said at least one first electrode plate configured for being electrically connected to a virtual ground, each of said at least one second electrode plate configured for being connected to a voltage signal source.

4. The container of claim 3, wherein each of said at least one first electrode plate and said at least one second electrode plate are coated with a non-stick coating.

5. The container of claim 4, wherein said non-stick coating comprises polytetrafluoroethylene.

6. The container of claim 3, wherein each of said at least one first electrode plate and each of said at least one second electrode plate are disposed at a predetermined depth from a bottom of said container.

7. The container of claim 1, further comprising:

an electrical cable having a plurality of conductors, each of said plurality of conductors electrically connected at a first end thereof to a respective one of said first electrode and said second electrode, an electrical connector electrically connected to a second end of each of said plurality of conductors.

8. The container of claim 7, wherein said container body defines an orifice, said electrical cable extending through said orifice.

9. The container of claim 8, further comprising a sealing member sealingly engaging each of said orifice and said electrical cable.

10. The container of claim 1, further comprising a ground wire attachment means, said ground wire attachment means configured for receiving and retaining a grounding wire to thereby electrically connect said container body to a ground potential.

11. The container of claim 10, wherein said ground wire attachment means is one of affixed to and integral with said conductive container body.

12. The container of claim 1, wherein said sensor assembly is mechanically secured to said container body by electrically nonconductive fastening means.

14. The capacitive sensing assembly of claim 13, further comprising a non-stick coating disposed on each of said at least one first electrode and said at least one second electrode.

15. The capacitive sensing assembly of claim 14, wherein said non-stick coating comprises polytetrafluoroethylene.

17. The electrophotographic printing machine of claim 16, wherein said sensor assembly comprises a capacitive sensor.

18. The electrophotographic printing machine of claim 17, wherein said capacitive sensor comprises at least one first electrode plate and at least one second electrode plate spaced apart from a corresponding first electrode plate, each of said at least one first electrode plate configured for being electrically connected to a virtual ground, each of said at least one second electrode plate configured for being connected to a voltage signal source.

19. The electrophotographic printing machine of claim 17, wherein each of said at least one first electrode plate and said at least one second electrode plate are coated with a non-stick coating.

20. The electrophotographic printing machine of claim 19, wherein said non-stick coating comprises polytetrafluoroethylene.

21. The electrophotographic printing machine of claim 18, further comprising:

an electrical cable having a plurality of conductors, each of said plurality of conductors electrically connected at a first end thereof to a respective one of said first electrode and said second electrode, an electrical connector electrically connected to a second end of each of said plurality of conductors.

22. The electrophotographic printing machine of claim 18, further comprising a ground wire attachment means, a ground wire attached at a first end thereof to said ground wire attachment means and at a second end thereof to a chassis of said electrophotographic printing machine to thereby electrically connect said container body to ground potential.

13. A capacitive sensing assembly for use with a container, said container having a body, said body constructed of an electrically conductive material and defining a container cavity, said capacitive sensing assembly comprising:

at least one first electrode configured for being disposed within said container cavity and being electrically isolated therefrom; and

at least one second electrode configured for being disposed within said container cavity and being electrically isolated therefrom.

16. An electrophotographic printing machine, comprising:

at least one waste container having an electrically conductive container body, said container body defining a container cavity; and

a sensor assembly disposed within said container cavity, said sensor assembly being electrically isolated from said container body, said sensor assembly configured for sensing a level of material within said container cavity.