Conveyor friction scale

• US 5,547,034 A
• Filed: 01/10/1994
• Issued: 08/20/1996
• Est. Priority Date: 01/10/1994
• Status: Expired due to Fees

• Current Assignee: Accu-Sort Systems Incorporated (Datalogic S.p.A.)
• Original Assignee: Accu-Sort Systems Incorporated (Datalogic S.p.A.)
• Inventors: Scott, William, Skokowski, Richard, Wurz, Albert
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Gibson, Randy W.
• Application Number:
  US08/179,422
• Time in Patent Office: 953 Days
• Field of Search: 177/16, 177/119, 177/120, 177/121, 177/25.13, 177/1, 177/50, 177/145, 73/9
• US Class Current: 177/25.13
• CPC Class Codes: G01G 11/006 Special taring or checking devices therefor devices for determining tare weight in general G01G23/14
• CPC Class Codes: G01G 11/046 involving digital counting
• CPC Class Codes: G01G 19/03 for weighing during motion G01G19/04, G01G19/07 take precedence check weighing of materials dispensed into removable containers G01G15/00; weighing a continuous stream of material during flow G01G11/00; G01G19/02, e.g. G01G19/022, G01G19/045 take precedence

Abstract

A conveyor scale assembly for use in combination with a conveyor belt for weighing an article on the moving conveyor belt. The conveyor scale assembly is comprised of a slider bed which contacts the underside of the moving conveyor belt which generates a friction force between the conveyor belt and the slider bed. Attached to the slider bed is a sensor which continuously measures the friction force and transmits data representing the measured friction force. A CPU receives and processes the representative data and provides a weight for the article on the conveyor belt.

Claims

1. An improved combination of a conveyor scale assembly and a conveyor for weighing an article on a moving conveyor belt comprising:

support means which contacts the underside of the moving conveyor belt and generates a friction force;

sensor means attached to the support means which continuously measures the friction force and transmits data representing the measured friction force to a logic means; and

logic means for receiving and processing the representative data to provide a weight for the article on the moving conveyor belt.

2. The improved combination of claim 1 further comprising calibration means which continuously transmits data representing a friction force for a known weight to the logic means, and tracking means which identifies the belt position and transmits belt position data to the logic means;

the logic means calculates a coefficient of friction for each increment of the belt and provides the weight of the article on the belt based on the increment of the belt on which the article rests.

3. The improved combination of claim 2 further comprising noise suppression means for measuring forces acting on the scale due to induced vibration and transmitting data to the logic means representing the forces due to vibration;

the logic means utilizes the vibration data to remove a noise component from the measured friction force data.

4. The improved combination of claim 1 wherein the sensor means is a load cell.

5. The improved combination of claim 1 further comprising a photoeye for sensing the presence of the leading and trailing edges of the article on the conveyor.

6. An improved combination of a conveyor scale assembly and a conveyor for weighing articles on a moving conveyor belt comprising:

multiple support means which contact the underside of the moving conveyor belt, each support means generates a friction force;

sensor means attached to each of the support means which continuously measure the friction force generated by each respective support means and transmit data representing the measured friction force to a logic means; and

logic means for receiving and processing the representative data to provide weights for the articles on the moving conveyor belt.