Skew Axes Helical Gear Set For Auto Thread-Trimming Lockstitch

Skew Axes Helical Gear Set For Auto Thread-Trimming Lockstitch

I. Design Orientation —— “Transmission Hub” of Automatic Thread-Trimming Lockstitch Sewing Machine
This is a helical gear transmission assembly for non-parallel shafts, specially designed for automatic thread-trimming lockstitch sewing machines. It focuses on solving the problems of “compact spatial transmission + precise coordination of thread - trimming actions”:
1.Spatial Adaptability
Adopting a 90° non-parallel shaft layout, it replaces the traditional bevel gear/spur gear set, reducing the volume of the transmission mechanism in the sewing machine head by 35%. It meets the compact design requirement of automatic thread-trimming lockstitch sewing machines for “multi - mechanism integration (sewing, thread-trimming, feeding)” and supports the miniaturization of equipment (such as desktop lockstitch sewing machines).
2.Functional Modularity
The gear pair integrates the functions of power transmission, thread-trimming triggering, and sequence control. Through standardized tooth profile parameters, it is compatible with the transmission systems of mainstream lockstitch sewing machine brands at home and abroad, reducing the R&D and maintenance costs of the equipment.

II. Transmission Logic——Dual-Track Coordination of “Power Chain + Thread-Trimming Chain”
The gear pair constructs the “motor - actuator” transmission network of the lockstitch sewing machine and simultaneously drives two core actions: sewing and thread-trimming:
1.Sewing Power Chain
▶Transmission: The high-speed rotation output by the motor is decelerated and torque-increased by the driving gear, and the power is distributed to the hook mechanism and the feeding mechanism, ensuring the uniform density of sewing stitches.
▶Synchronization Control: Utilizing the high contact ratio of helical gear meshing, the transmission vibration is reduced, making the needle penetration and hook thread-catching accurately synchronized, with a thread-skipping rate ≤ 0.1%.
2.Thread-Trimming Action Chain
▶Trigger Mechanism: When sewing is completed, the electronic control system triggers the thread-trimming electromagnet, the thread-trimming cam linked with the gear pair rotates, and pushes the moving knife assembly to complete the “thread - separating - cutting” action, with a thread-trimming response time ≤0.2s.
▶Precision Guarantee: The self-lubricating property of the driven gear ensures the uniform rotation of the thread-trimming cam, and the shearing gap between the moving knife and the fixed knife is stably maintained at 0.05-0.1mm, realizing the “one-cut-for-both” of the upper thread and the bobbin thread, with a thread-trimming success rate ≥99.5%.

III. Adaptation Scenarios —— “Full - Working - Condition Coverage” of Automatic Thread-Trimming Lockstitch Sewing Machine
The gear pair is customized in terms of materials and parameters to adapt to the diversified application scenarios of lockstitch sewing machines:
1.Fabric Compatibility
▶For light and thin fabrics: Small-module gears (m=1-1.5mm) are adopted to reduce the transmission torque, and the feeding precision of the feeding mechanism is ≤± 0.1mm, avoiding fabric wrinkling.
▶For heavy-duty fabrics: Large-module gears (m=2-3mm) are selected, the tooth surface load-bearing capacity is increased by 40%, and the thread-trimming shearing force reaches 5-10N, ensuring the integrity of thread-trimming for heavy-duty fabrics.
2.Process Adaptability
▶Ordinary Lockstitch Sewing: The transmission ratio of the gear pair i=10-15, and the sewing speed is 2000-3000 stitches per minute, meeting the demand for mass production.
▶Decorative Sewing: Through the design of multi-start worms/helical gears, the stepless adjustment of the transmission ratio is realized, supporting the needle swing amplitude of 2-10mm and adapting to the demand for complex stitch patterns.

This set of helical gear pairs for non-parallel shafts, with its compact spatial transmission design, dual-track action coordination logic, and full-scenario adaptation capability, becomes the “transmission hub” of the automatic thread-trimming lockstitch sewing machine. It not only meets the core demands of the lockstitch sewing machine for “efficient sewing + precise thread-trimming” but also promotes the equipment upgrade of the garment-making industry through the balance of standardization and customization —— Small gears drive high efficiency and support the transformation of the garment industry from “labor-intensive” to “technology-intensive”.

DINGSCO Precision Gear Solutions — Pioneering Force in Equipment Transmission

Core Advantages: Cutting-Edge Equipment × Digitalized Processes × Full-Cycle Services

As a leading precision gear manufacturer, DINGSCO specializes in customized production of micro high-precision spiral bevel gears and hypoid gears through our multiple CNC seven-axis five-linkage spiral bevel gear grinding/milling machines and Gleason spiral bevel cutter technology. With DIN 6 precision class (tooth profile error ≤ ±5μm), 95%+ transmission efficiency, and ultra-high reduction ratios, we deliver reliable transmission solutions for robotics, motor drives, new energy vehicles, and more.

Why Choose DINGSCO?
✅ High Precision: Achieving DIN 6 grade accuracy, leading the industry in controlling tooth profile errors.

✅ High Efficiency: With a single - stage reduction ratio of up to 300:1, and a transmission efficiency of over 95%.

✅ Durability: 40% lower lifecycle cost, <0.5% failure rate.
✅ Fast response: The digital process can shorten the delivery cycle to 20 working days.

Contact Us Soon for gear optimization proposals and 3D meshing simulations!

Our company was formerly known as Changsha Double Star Gear Industrial Co., Ltd, which was established in 1994. It is a directly affiliated university-run enterprise founded by Central South University Professor Zeng Tao, the leading expert on spiral bevel gears in China. It was later renamed as Changsha Senjie Gear Co., Ltd (abbreviated as "CSG") in 2016. CSG is a production R&D base specializing in professional design, reserch, manufacture and sales of high-quality small module spiral bevel gears and high reduction hypoid gears and cylindrical gears. In 2023, Hunan Dinghan New Material Technology Co., Ltd. was established as a specialized international export business department. CSG has strong scientific research and development capabilities and is also equipped a full set of advanced equipment including seven-axis five-linkage CNC spiral bevel gear grinding machines and gear milling machines. By making the best use of the scientific and technological achievements and equipment of the Gear Research Institute of Central South University, machanical processing, heat treatment and testing. We have developed high-quality products featuring high reduction, high speed, heavy load, low noise and less teeth for users.

With the quality policy of "scientific and technological innovation, quality first, being first-class firm and customer‘s satisfaction", we have won the trust of well-known domestic and abroad enterprises with stable and excellent quality. It is committed to be a pioneer of the industry of China's small-module spiral bevel gears, and is dedicated to providing service for any related industry requiring industrial robots, CNC turning and milling compound power tool turrets, industrial sewing machines, reducers, bicycles, power tools and aeromodelling. We sincerely look forward to your cooperation!