Pivoting load-bearing assembly with force sensor

Patent metadata

Field	Value
Publication number	US-12024412-B2
Application number	US-202017137025-A
Country	US
Kind code	B2
Filing date	Dec 29, 2020
Priority date	Oct 30, 2014
Publication date	Jul 2, 2024
Grant date	Jul 2, 2024

Abstract

A load-bearing assembly including a clamping-force sensor in a pivoting support assembly that is adjustable to vary a radial spacing between a pivot pin and a clamp pad mounted on the support assembly. A plurality of clamping-force sensors may be included in a plurality of pivoting clamp pad support assemblies to support a clamp pad and may be arranged to sense the magnitude of a clamping force exerted by a particular adjustable pivoting clamp pad support assembly and send signals indicative of the magnitude of the force to a controller. A load sensor may be located between a pivot pin and a bearing block, or strain gauges may be mounted in the pivoting bearing block so as to measure forces carried through the bearing block. Force values sensed and transmitted to the controller may be used to evaluate and adjust the clamp arm assembly to grasp a load with a desired clamping force or distribution of clamping forces.

First claim

We claim:

1. A method of adjusting a load grasping assembly for a lift truck including a load grasping assembly including a clamp arm, a clamp pad mounted to the clamp arm through a pivoting clamp pad support assembly, at least four pairs of clamp shear strain gages for measuring clamp force, at least two pairs of vertical shear strain gages for measuring vertical force, the method comprising:
(a) providing a test load body having a predetermined configuration;
(b) grasping the test load body with the load grasping assembly;
(c) obtaining a signal from said clamp shear strain gages representative of a magnitude of a force exerted on said clamp pad in a predetermined direction by said pivoting clamp pad support assembly;
(d) obtaining a signal from said vertical shear strain gages representative of a magnitude of vertical load;
(e) determining from said signal the magnitude of a grasping force exerted in said predetermined direction and a vertical direction by said clamp pad support assembly while grasping the test load body;
(f) determining from said signal a lateral and horizontal center of gravity of the vertical load; and
(g) in response, adjusting a clamping force applied to said clamp arm.

2. A method of adjusting a load grasping assembly for a lift truck including a load grasping assembly including a clamp arm, a clamp pad mounted to the clamp arm through a pivoting clamp pad support assembly, a force sensor included in said clamp pad support assembly, and at least a pair of vertical load sensors, wherein said clamp pad is mounted on said clamp arm using a plurality of said pivoting clamp pad support assemblies each including a respective said force sensor, the method comprising:
(a) providing a test load body having a predetermined configuration;
(b) grasping the test load body with the load grasping assembly;
(c) obtaining a respective signal from each of said plurality of force sensors representative of a force exerted in a predetermined direction by a respective one of said plurality of pivoting clamp pad support assemblies and from each vertical load sensor;
(d) determining a separate respective grasping force exerted in said predetermined direction by each one of said plurality of pivoting clamp pad support assemblies while grasping the test load body;
(e) determining a distribution of said grasping forces of said plurality of clamp pad support assemblies of a clamp arm;
(f) comparing said distribution of said grasping forces of said plurality of clamp pad support assemblies with a predetermined desired distribution; and
(g) in response, adjusting a distance adjustment assembly included in one of said pivoting clamp pad support assemblies and thereby adjusting a radial distance between a pivot axis of said one of said clamp pad support assemblies and said clamp pad mounted through said one of said plurality of pivoting clamp pad support assemblies.

3. The method of claim 2 , wherein said step of determining a distribution of said grasping forces includes observing the respective electrical signal representative of the respective force exerted by each of said plurality of pivoting clamp pad support assemblies.

4. The method of claim 3 including receiving a respective signal from each of said vertical force sensors in a controller.

Assignees

• Cascade Corp

Inventors

• White Brian Sinclair
• Roncari Davide
• Walthers Christopher M

Classifications

• B66F9/183 Primary

  Coplanar side clamps · CPC title