WEIGHING DEVICE FOR LOGGING TRUCKS OR THE LIKE

• US 3,661,220 A
• Filed: 11/01/1971
• Issued: 05/09/1972
• Est. Priority Date: 11/01/1971
• Status: Expired due to Term

• Current Assignee: Lodec Incorporated
• Original Assignee: Carl R. Harris
• Inventors: Harris, Carl R.
• Primary Examiner(s): Tomsky, Stephen J.
• Assistant Examiner(s): Miller, Jr., George H.
• Application Number:
  US05/194,273
• Time in Patent Office: 190 Days
• Field of Search: 177/136,211,229,255 73/141A
• US Class Current: 177/136
• CPC Class Codes: G01G 19/12 having electrical weight-sensitive devices
• CPC Class Codes: G01G 3/1406 combined with special measuring circuits

Abstract

A load cell system including a strain gage mounting assembly to be located between the bolster and frame of a truck such as used in the logging industry. A heavy steel block having longitudinal slots cut therein is secured to the bolster to transmit forces to the frame in a manner such that a sensing beam is created. Sensing devices secured to the assembly respond to stresses of the beam to provide force indications to an indicator which shows the weight of the load on the truck.

Claims

1. A strain gage assembly for a truck weighing system adapted to be located between the load carrying portion of the vehicle and the vehicle frame, comprising in combination:

an elongated steel block having slots cut in the opposite ends thereof substantially parallel to the vehicle frame, and including edge support surfaces at the opposite ends thereof for maintaining the central portion of the block elevated above the truck frame and defining beam means responsive to loads imposed on the upper surface of the assembly; and

strain sensing means located along a longitudinal surface of said block and responsive to strain induced in said assembly by the loads imposed thereon.

2. An assembly as recited in claim 1, further comprising means for securing said block to the vehicle frame, said means including means defining apertures at both ends of said block, said apertures passing through the portions thereof below said slots, fastening means affixed to said vehicle frame which extend through said apertures, said fastening means including a layer of resilient material for permitting free movement of said block in response to applied loads.

3. An assembly as recited in claim 1, further comprising bearing support plates inserted between said edge support surfaces and the vehicle frame.

4. An assembly as recited in claim 1, wherein said strain sensing means comprises a pair of strain gages located on the bottom surface of said block below each of said slots.

5. An assembly as recited in claim 4, further comprising means connecting the strain gages in each of said pairs in opposition to provide signals proportional to the load on each end of said block, and means adding said signals to provide an output signal.

6. An assembly as recited in claim 5, further comprising a trimming resistance means connected in circuit with each of said strain gage pairs, said trimming resistance means being adjustable to equalize said signals with equal applied loads on the ends of said block.

7. A truck weighing system comprising:

a. a plurality of load sensors, each load sensor located between a load carrying portion of the truck and a corresponding portion of the vehicle frame, and each load sensor including a straIn gage assembly comprising an elongated steel block having slots cut in the opposite ends thereof substantially parallel to the vehicle frame, and including edge support surfaces at the opposite ends thereof for maintaining the central portion of the block elevated above the truck frame and defining beam means responsive to loads imposed on the upper surface of the assembly; and

strain sensing means located along the lower surface of said block and responsive to strain induced in said assembly by the loads imposed thereon;

b. means coupled to said strain sensitive means including means for providing an output signal proportional to the load supported by said load carrying portions; and

c. indicator means responsive to said output signal for displaying the value of said load.