Weighing system for vehicles

• US 4,917,197 A
• Filed: 02/10/1989
• Issued: 04/17/1990
• Est. Priority Date: 02/10/1989
• Status: Expired due to Term

• Current Assignee: Waste Management Incorporated
• Original Assignee: Blodgett & Blodgett PC
• Inventors: Waite, Robert K. Jr.
• Primary Examiner(s): MILLER JR, GEORGE
• Application Number:
  US07/309,341
• Time in Patent Office: 431 Days
• Field of Search: 177/136-140, 177/210 R
• US Class Current: 177/137
• CPC Class Codes: B60G 2204/11 Mounting of sensors thereon
• CPC Class Codes: B60G 2400/61 Load distribution
• CPC Class Codes: G01G 19/12 having electrical weight-sensitive devices

Abstract

A weighing system for a vehicle having a spring supportive frame which moves relative to the axles of the vehicle in response to changes in load weight on the vehicle. The weighing system includes at least one position indicator for each axle to be monitored which provides electrical signals which vary in accordance with the built position of the frame relative to the axle which is being monitored. The weighing system also includes a programmed central processing unit for receiving the electrical signals from the position indicator and for calculating the load weight on the frame, based on the value of the electrical signals.

Claims

1. A weighing system for a vehicle having a frame, a plurality of axles, a plurality of wheels rotatably mounted on the axles and a plurality of springs operatively connecting the axles and the frame for yieldingly supporting the frame above the axles so that the frame moves vertically toward and away from said axles in response to weight which is added to and subtracted from the frame, said weighing system comprising:

(a) a position indicator for sensing the relative vertical movement between the frame of the vehicle and one of said axles and for providing electrical signals which vary in accordance with the relative vertical position of said frame with respect to said one axle and which are indicative of the load weight on said frame, said position indicator comprising a linear motion position transducer which produces analog electrical signals, and an electrical digitizer for converting said analog signals to digital signals, said linear motion transducer comprising a housing which is fixed against vertical motion relative to said frame, a rod which is slidably mounted within said housing, said rod having a free end which extends from said housing and which operatively engages said one axle, and means for biasing said rod toward said axle and away from said housing so that said rod moves vertically with said one axle and relative to said housing, and

(b) a programmed central processing unit which is operatively connected to said position indicator for receiving said electrical signals and for calculating the weight on said frame based on the value of said electrical signal.

2. A weighing system for a vehicle as recited in claim 1, wherein said linear motion transducer further comprises a compressible resilient sleeve;

one end of said sleeve being attached to the free end of said rod and the opposite end of said sleeve being attached to said housing so that said sleeve encloses said rod.

3. A weighing system for a vehicle as recited in claim 2, wherein said sleeve is pleated and is made of an elastomeric material.

4. A weighing system for a vehicle as recited in claim 1, further comprising a cap which is fixed to the free end of said rod, said end cap being made of a tough polymer which has high impact strength.

5. A weighing system for a vehicle as recited in claim 4, wherein said polymer is acetyl.

6. A weighing system for a vehicle having a frame, a plurality of axles, a plurality of wheels rotatably mounted on the axles and a plurality of springs operatively connecting the axles and the frame for yieldingly supporting the frame above the axles so that the frame moves vertically toward and away from said axles in response to weight is added to and subtracted from the frame, said vehicle having at least one front axle and at least two rear axles, said weighing system comprising:

(a) a position indicator on each side of the vehicle for the two rear axles for sensing the relative vertical movement between the frame of the vehicle and said axles and for providing electrical signals which vary in accordance with the relative vertical position of said frame with respect to said axles and which are indicative of the load weight on said frame, each of said position indicators comprising;

(1) a block which is located between the two rear axles,

(2) a linear motion position transducer which is operatively connected at one end of the frame of the vehicle and at its opposite end of said block,

(3) a first connector which comprises a resilient flexible bar which is fixed at one end to said block and which is operatively connected at its opposite end to one of said rear axles, and

(4) a second connector which comprises a resilient flexible bar which is fixed at one end to said block and which is operatively connected at its opposite end to the other of said rear axles so that the vertical position of said block is an average of the vertical positions of said rear axles relative to said frame, and

(b) a programmed central processing unit which is operatively connected to said position indicator for receiving said electrical signals and for calculating the weight on said frame based on the value of said electrical signal.

7. A weighing system as recited in claim 6, wherein said bar curves upwardly from said block and the corresponding one of said rear axles.