Sewing Machine Gripper System Three-Dimensional Control Curve
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sewing machine gripper systems require significant design effort and complex arrangements to achieve accurate stitch formation, often resulting in high impact forces and noise, especially at high speeds.
Innovation Solution
The gripper system is designed with a three-dimensional control curve that adapts to axial movements during radial pivoting of the capsule fan, allowing the button to contact the control cam over a larger area, optimizing the bearing selection for both button and fan lever movements, thus reducing design complexity and noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a conventional control cam with a two-dimensional control curve is used, then the design is simpler, but the button contacts the control cam only at certain points resulting in high impact forces and noise
Solution Approach 1:
The control curve is extended from a two-dimensional curve to a three-dimensional surface by adding axial dimension. The control cam now has a control surface that extends in the axial direction, allowing the button to contact over a larger area rather than at discrete points, thereby reducing impact forces and noise during operation
2Manufacturing precision
If accurate stitch formation is ensured through complex cam and transmission arrangements, then stitching precision is improved, but the design effort and device complexity increase significantly
Solution Approach 1:
By extending the control curve into the third dimension (axial direction), the patent achieves accurate control of the capsule fan movement with a simpler overall design. The three-dimensional control surface provides continuous contact guidance that ensures precise stitch formation without requiring complex transmission mechanisms
Solution Approach 2:
The control cam with three-dimensional control surface serves multiple functions simultaneously: it guides the radial pivoting of the capsule fan, controls the axial movements of the button, and ensures accurate timing for stitch formation, thereby reducing the need for separate control mechanisms
3Ease of operation
If the fan shaft is arranged parallel to the gripper drive shaft, then the transmission of movements is simpler, but the bearing selection cannot optimize both button and fan lever pivoting movements simultaneously
Solution Approach 1:
The patent employs an asymmetric arrangement where the fan shaft is positioned perpendicular to the gripper drive shaft rather than parallel. This asymmetric configuration allows different bearing types to be selected for optimal performance in each direction: one bearing handles the button pivoting movements while another bearing optimizes the fan lever pivoting movements, achieving superior operational ease
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The machine has a push button (37) fastened to a rotationally driving radial cam (39). The radial cam is rotationally driven around an axis (13) of a gripper drive shaft (14). The radial cam is formed at an outer periphery of a control disk (38). A capsule lifter (33) is rotatably mounted around an axis (35) perpendicular to the axis (13) of the gripper drive shaft. The radial cam exhibits different radial distances from the axis (13) for adapting to the axial movements of the push button in the direction of the gripper drive shaft. The cam is connected with a gripper in a torque proof manner.