Device and method for electronically measuring the fullness of a trash receptacle

• US 5,558,013 A
• Filed: 12/30/1992
• Issued: 09/24/1996
• Est. Priority Date: 05/07/1992
• Status: Expired due to Term

• Current Assignee: James O. Blackstone Jr
• Original Assignee: James O. Blackstone Jr
• Inventors: Blackstone, James O. Jr.
• Primary Examiner(s): GERRITY, STEPHEN FRANCIS
• Application Number:
  US07/998,525
• Time in Patent Office: 1,364 Days
• Field of Search: 100/35, 100/43, 100/48, 100/50, 100/52, 100/99, 100/229 A
• US Class Current: 100/35
• CPC Class Codes: B30B 9/3007 Control arrangements
• CPC Class Codes: B30B 9/3042 Containers provided with, or connectable to, compactor means

Abstract

An electronic device for monitoring the fullness of a trash receptacle is disclosed. The trash receptacle is associated with a compactor that has a compression member for compacting trash within the receptacle. The compression member is powered by an electric motor. The current drawn by the electric motor is monitored by a current sensor. As more trash is deposited and compacted, the sensor detects an increased current flow in the electric motor. A microprocessor operates on the current sensor readings to determine the relative fullness of the receptacle. The current sensor readings are evaluated by an algorithm which distinguishes the current readings due to foward compactor ram motion of the compression member from current readings due to reverse compactor ram motion. The algorithm compares modified derivatives of the current sensor readings to threshold values of the derivatives in order to determine the relative fullness of the receptacle.

Claims

1. An apparatus to monitor the amount of trash in a trash receptacle and compactor unit, said compactor unit having an electric motor for compacting trash within said trash receptacle, said electric motor drawing a first current when compacting said trash and a second current when repositioning after compacting said trash, said apparatus comprising:

means for measuring the current drawn by said electric motor during operation of said comparator unit; and

means responsive to said current drawn by said electric motor during operation of said compactor unit for determining the amount of trash within said trash receptacle, wherein said responsive means determines a derivative of said current drawn and compares said derivative to a derivative threshold to determine said amount of trash.

2. The apparatus of claim 1 wherein said responsive means determines said derivative from the absolute value of two consecutive modified derivatives of said current drawn.

3. The apparatus of claim 2 wherein said responsive means determines each said modified derivative by averaging the absolute values of two consecutive first derivatives of said current drawn.

4. A trash compactor, comprising:

a trash receptacle;

a compactor unit having an electric motor for compacting trash within said trash receptacle, said electric motor drawing a first current when compacting said trash and a second current when repositioning after compacting said trash;

means for measuring the current drawn by said electric motor during operation of said compactor unit; and

means responsive to said current during operation of said compactor unit for determining the amount of trash within said trash receptacle, wherein said responsive means determines a derivative of said current drawn and compares said derivative to a derivative threshold to determine said amount of trash.

5. The apparatus of claim 4 wherein said responsive means determines said derivative from the absolute value of two consecutive modified derivatives of said current signal.

6. The apparatus of claim 5 wherein said responsive means determines each said modified derivative by averaging the absolute values of two consecutive first derivatives of said current signal.

7. A method of monitoring the amount of trash in a trash receptacle and comparator unit, said comparator unit having an electrical motor, comprising the steps of:

measuring a first current drawn by said electric motor when compacting said trash and a second current when repositioning after compacting said trash; and

determining said amount of trash in said trash receptacle by comparing a derivative of said current drawn to a derivative threshold.

8. The method of claim 7 wherein said derivative is determined from the absolute value of two consecutive modified derivatives of said current drawn.

9. The method of claim 8 wherein each modified derivative is determined by averaging the absolute values of two consecutive first derivatives of said current drawn.