Pivoting Load-Bearing Assembly for Directional Clamp Force Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing load-bearing assemblies in lift trucks struggle to accurately measure and distribute clamping forces in a specific direction, particularly for uneven loads like cartons or paper rolls, and existing strain gauge arrangements are impractical and costly for smaller pivot pins.
Innovation Solution
A pivoting load-bearing assembly with a force sensor that isolates and measures clamping forces in a particular direction using a pivoting support assembly, comprising a bearing block, pivot pin, and a force sensor to provide a signal representative of the clamping force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a strain gauge arrangement is incorporated in large shackle pins or pivot pins to measure load forces, then force measurement capability is provided, but the arrangement becomes impractical and costly for smaller pivot pins, and may require greater manufacturing precision and compromise the strength of the pivot pin
Solution Approach 1:
The patent introduces a separate force sensing element (load cell or force sensor) as an intermediary component that is distinct from the pivot pin itself. This sensor is positioned to measure forces acting on the pivot pin without being integrated into the pin structure, thereby avoiding the need to incorporate strain gauges directly into the pivot pin. This resolves the contradiction by providing accurate force measurement while maintaining the structural integrity and manufacturing simplicity of the pivot pin.
2Adaptability or versatility
If clamp pads are allowed to pivot freely to accommodate clamp arm deflection and conform to load shape, then adaptability to various load shapes is improved, but the ability to accurately measure and control clamping force in a specific direction is reduced
Solution Approach 1:
The patent segments the clamp pad assembly into distinct functional components: the pivotable clamp pad support assembly that provides adaptability to load shapes, and the separate force sensor that accurately measures clamping force. This segmentation allows the clamp pad to pivot freely for conformability while the force sensor independently and accurately measures the clamping force in the specific direction, resolving the contradiction between adaptability and measurement precision.
Solution Approach 2:
The force sensor acts as an intermediary element that measures the clamping force without interfering with the pivotable connection between the clamp pad support assembly and the clamp arm. This intermediary sensing mechanism enables accurate force measurement while maintaining the freedom of movement necessary for the clamp pad to conform to various load shapes.
3Ease of operation
If hydraulic pressure is controlled to regulate clamping force, then force control is achieved, but actual clamping force measurement during operation is not available
Solution Approach 1:
The patent implements a feedback mechanism by incorporating a force sensor that provides real-time measurement of the actual clamping force during operation. This measured force information can be fed back to the control system, allowing for verification and adjustment of the hydraulic pressure control. This resolves the contradiction by maintaining the ease of operation through hydraulic control while eliminating the loss of information by providing actual force measurement data during operation.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
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.