WEIGHING DEVICES

• US 3,780,817 A
• Filed: 02/28/1969
• Issued: 12/25/1973
• Est. Priority Date: 02/28/1969
• Status: Expired due to Term

• Current Assignee: John A. Videon
• Original Assignee: John A. Videon
• Inventors: Videon, John A.
• Primary Examiner(s): Miller, Jr., George H.
• Application Number:
  US04/803,285
• Time in Patent Office: 1,761 Days
• Field of Search: 177/136,137,138,211,234 73/88.5,141A
• US Class Current: 177/136
• CPC Class Codes: G01B 7/18 using change in resistance
• CPC Class Codes: G01G 19/12 having electrical weight-sensitive devices
• CPC Class Codes: G01G 3/1406 combined with special measuring circuits
• CPC Class Codes: G01G 3/142 Circuits specially adapted therefor

Abstract

This invention is directed to a load-indicating apparatus for measuring the deflection of a relatively stiff non-spring member. The apparatus includes a non-spring member such as the stationary axle of a truck which is capable of flexing in a predetermined direction under load. Mounted on the axle are two spaced-apart, rigid supports which upstand therefrom in a direction whereby the upper ends of the supports will move toward and away from each other as the axle flexes. A transducer is connected to the upper ends of the supports for measuring the distance therebetween as they move and to provide an indication of the load on the axle.

Claims

1. A load-measuring apparatus for measuring the deflection of a relatively stiff non-spring member comprising a non-spring member capable of flexing in a predetermined direction in proportion to a load thereon, two spaced apart rigid supports fixedly secured to said member and upstanding thereon, the upper ends of said supports being relatively movable toward and away from each other in proportion to the flexure of said member, means connected to the upper ends of said supports for measuring the distance therebetween as they move, said means including a device having spaced apart mounting portions secured to said upper ends, respectively, at least one transducer fitted to said device at a location between said mounting portions, said transducer being responsive to movement of said device, said device further including a beam element having opposite ends secured to said upper ends, respectively, said beam element being bendable in correspondence with bending of said non-spring member, said transducer being mounted on said beam element, said transducer being a strain gauge, said beam element being a spring metal bar, said strain gauge being mounted on one surface of said bar between the ends thereof.

2. The apparatus of claim 1 in which a second strain gauge is mounted on a surface of said bar opposite from the first strain gauge, and said bar is stressed to curve toward said non-spring member.

3. The apparatus of claim 2 in which said non-spring member is a vehicle axle, said supports are metal blocks welded to said axle, said blocks having flat upper surfaces which incline downwardly toward each other, said bar being flat and lying flat against said inclined surfaces and thereby being curved as aforesaid, members removably securing said bar to said inclined surfaces, four strain gauges on said bar, two on each surface thereof, and a bridge circuit containing said gauges in the legs thereof, respectively, one pair of said legs having therein the gauges on the top surface of said bar, the other pair of said legs having therein the gauges which are secured to the bottom surface of said bar, said circuit having two terminals at opposite corners, each terminal being connected between the two gauges of each gauge pair, and meter means connected to said terminals for indicating the change in resistance of said gauges.

4. The apparatus of claim 1 in which said beam element is a flat spring metal bar secured with the surfaces thereof normal to the plane of bending of said non-spring member, said non-spring member including a hollow axle, said bar being mounted internally of said axle on a pair of upstanding blocks fixedly secured to the bottom portion of said axle, said blocks having a clearance with the upper portion of said axle such that the upper ends thereof can move relative to said upper portion.

5. The apparatus of claim 4 including means for stressing the bar into a downward curvature, there being four strain gauges, two being mounted on the top surface and two on the bottom surface of said bar.