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T Series Cordless Spring Mechanism for Bamboo Roman Shade

Gianna — Thu, 15 Jan 2026 07:48:13 +0000

Quick Summary

The Cordless Spring Mechanism is the core architecture that enables bamboo Roman shades to deliver
pull-and-stop operation without external cords.
The T series system integrates a T1 Spring Box (with a constant force spring),
Cord Reel, Cord Bundle, and Fiber Glass Hexagonal Rod to provide
balanced lift assistance, stable holding at any height, and reduced entanglement risk for children and pets.

What Is the T Series Cordless Spring Mechanism?

The Cordless Spring Mechanism for bamboo Roman shades is a fully mechanical lift system designed for
direct bottom-rail operation. The shade moves by winding and unwinding internal lift cords—without external pull cords.
This improves safety, maintains clean aesthetics, and delivers intuitive manual control.

System Composition

T1 Spring Box (housing a constant force spring)
Cord Reel (for controlled cord winding)
Cord Bundle (for cord fixing and tension adjustment)
Fiber Glass Hexagonal Rod (for torque transmission and synchronized rotation)

Top Mounting & Shaft Path

The T1 Spring Box and Cord Reel are fixed at the top of the bamboo Roman shade
and locked onto the wooden headrail using screws. A Fiber Glass Hexagonal Rod passes through both
modules, acting as the rotating shaft that transfers torque and ensures consistent winding behavior.

Internal Cord Routing

Lift cords wrap around the Cord Reel, then route through the bamboo slats and terminate at the bottom rail.
The Cord Bundle secures the cords and allows fine tension tuning to match shade size, weight, and travel.
In a true Cordless Spring Mechanism, cords remain internal—no external hanging loops are required.

How the Cordless Spring Mechanism Works

1) Fully Extended (Shade Down)

When the shade is fully lowered, most of the cord length is distributed through the bamboo slats, leaving fewer wraps
on the Cord Reel. The constant force spring inside the T1 Spring Box remains active,
continuously providing counterbalancing force to stabilize the system.

2) Lifting (Shade Up)

As the user pulls the bottom rail upward, the Fiber Glass Hexagonal Rod rotates. This rotation drives
the Cord Reel to take up cord length, increasing the number of wraps. Throughout travel, the
Cordless Spring Mechanism maintains a consistent feel because the constant force spring delivers
near-uniform output across the motion range.

3) Pull-and-Stop Control

A key experience advantage of the Cordless Spring Mechanism is its pull-and-stop behavior.
Users can stop at any height simply by releasing the bottom rail. The system’s force balance helps prevent drift,
rebound, or “creeping” when properly matched to the shade load.

Practical cue: As the shade moves, cord wraps on the Cord Reel decrease when lowering
and increase when lifting—while the Fiber Glass Hexagonal Rod synchronizes the rotation of the top modules.

Why a Constant Force Spring Improves the Cordless Spring Mechanism

The performance center of the T series Cordless Spring Mechanism is the constant force spring in the
T1 Spring Box. Compared with traditional spiral or torsion springs, constant force springs are preferred in position-holding lift architectures because they output a flatter force curve over travel.

Consistent Hand Feel Across Full Travel

With constant force behavior, lifting resistance stays more uniform from top to bottom. Users avoid the typical
“gets heavier at the end” sensation found in variable-torque spring designs.

Better Load Balance for Natural Bamboo Materials

Bamboo Roman shades can exhibit natural weight variation. A constant force spring helps compensate for uneven mass
distribution and reduces common issues such as tilt, skew, or uneven lifting.

Durability & Predictable Aging

A well-designed constant force spring can provide more predictable force retention over repeated cycles, improving
long-term stability and reducing service complaints—an important advantage for any premium Cordless Spring Mechanism.

Cordless Safety Advantages in Real Homes

One of the clearest benefits of a Cordless Spring Mechanism is the removal of external hanging cords.
By keeping cords internal—routed through the bamboo slats—this architecture helps reduce the entanglement risks
associated with traditional corded systems for children and pets.

No external pull cords for a cleaner, safer appearance
Internal cord routing through bamboo slats only
Safer user interaction via direct bottom-rail operation

System Components: Built to Work as One Cordless Spring Mechanism

T1 Spring Box

Houses the constant force spring
Provides stable lift assistance through travel
Key driver of long-term feel consistency

Cord Reel

Controls winding/unwinding of internal lift cords
Maintains orderly wraps to reduce localized wear
Wrap count increases when lifting and decreases when lowering

Fiber Glass Hexagonal Rod

Acts as the torque transmission shaft between top modules
Hexagonal profile improves anti-slip torque coupling
High strength-to-weight ratio supports stable rotation

Cord Bundle

Fixes cords at the bottom rail
Enables tension adjustment to refine balance and alignment
Improves installation repeatability for production builds

User Experience: Smooth, Quiet, and Intuitive

T series loading capacity test（For reference：Maxium）
Test base on 96″ 2.4M
2 cord reel without resistance			2 cord reel with full resistance		adjustable incremental bearing capacity range
Spring Spec.	Initiative Capacity/g	End Capacity/g	Initiative Capacity/g	End Capacity/g	Initially adjustable bearing capacity/g	End adjustable bearing capacity/g
0.09-16-3000	720	320	1220	150	720~1200	320~150
0.10-16-3000	870	480	1550	200	870~1550	480~200
0.11-16-3000	1070	580	1820	270	1070~1820	580~270
0.12-16-3000	1270	780	2270	370	1270~2270	780~370

A properly tuned Cordless Spring Mechanism delivers a refined tactile experience:
smooth lifting, quiet operation, and predictable stopping behavior. Users simply pull the bottom rail to move the shade
and release to stop—no dangling cords, no extra steps.

Pull-and-stop control at any height
Consistent lifting resistance enabled by constant force behavior
Cleaner aesthetics with no external cords
Lower perceived noise due to controlled winding and balanced load

Applications & Customization

The T series Cordless Spring Mechanism is designed specifically for bamboo Roman shades and similar natural-fiber Roman shade constructions.

System matching can be optimized based on shade width, height, fabric/bamboo mass, and bottom-rail weight.

Typical Use Cases

Bamboo Roman shades
Natural-fiber Roman shades
Premium residential projects requiring cordless safety architecture
OEM/ODM production programs needing consistent assembly and tuning

FAQ: T1 Cordless Spring Mechanism

Does the T1 Cordless Spring Mechanism have any external pull cords?

No. In this Cordless Spring Mechanism, cords are routed through the bamboo slats. Users operate the shade by pulling the bottom rail.

What component enables pull-and-stop behavior?

The constant force spring inside the T1 Spring Box provides balanced lift assistance, enabling stable stopping at different heights when the system is properly matched to the shade load.

What is the purpose of the Cord Bundle?

The Cord Bundle secures cords at the bottom rail and allows fine adjustment of cord tension for alignment and consistent operation.

Why use a Fiber Glass Hexagonal Rod?

The Fiber Glass Hexagonal Rod provides stable torque transmission and anti-slip coupling between the top modules, helping maintain synchronized rotation during lifting and lowering.

Field Insight

The real value of a Cordless Spring Mechanism is not only removing cords—it is achieving
system-level force balance that feels stable in daily use.

Constant force spring output defines whether the hand feel stays consistent across travel.
Cord winding geometry influences smoothness, noise perception, and wear behavior.
Tension calibration via Cord Bundle improves alignment, reduces skew, and increases build repeatability.
Shaft coupling through a Fiber Glass Hexagonal Rod supports stable torque transfer and synchronized motion.

In short: the T series solution is a complete Cordless Spring Mechanism platform for bamboo Roman shades—engineered
to deliver safer operation, cleaner design, and more predictable long-term behavior.

32mm Cordless Lift Control For Roller Blinds

vc-admin — Thu, 16 Oct 2025 10:11:23 +0000

Quick Summary

The Cordless Lift Control is a 32mm internal spring-driven lift mechanism
for roller blinds, replacing traditional cords and bead chains with a fully enclosed
constant force spring system.
Designed for OEM manufacturers, it delivers smooth push-pull operation,
stable positioning, and long-term mechanical reliability.

Key Features

True Cordless Lift Control – No exposed cords or chains
301 Stainless Steel Constant Force Spring
Integrated Brake System to prevent sudden drop
32mm Tube Compatibility for standard roller blinds
POM Spring Box Housing for low friction and quiet operation
Multiple Spring Force Options for different blind weights
OEM-Friendly Assembly with pre-tension pin locking

Product Overview

The Cordless Lift Control is engineered as an internal mechanical platform
that provides both lifting force and positional stability for roller blinds.
Instead of relying on external cords, the entire load-balancing function
is handled inside the aluminum tube.

Users operate the blind by gently pushing or pulling the bottom rail.
The internal spring stores and releases energy smoothly,
while the brake controls motion and holding position.

System Components

Spring Box – Core energy storage using a constant force spring
Brake – Controls speed and prevents free fall
Shaft – Transfers torque inside the tube
Circlip – Fixes axial position between components
Pin – Locks pre-tension during installation

Constant Force Spring Technology

At the heart of the Cordless Lift Control is a constant force spring
manufactured from 301 stainless steel.
The spring strip is wound into a compact spiral,
delivering near-uniform output force throughout the blind’s travel.

Compared with conventional torsion springs,
constant force springs reduce pull-force variation,
improve mid-position stability,
and enhance overall user experience.

Spring Options & Load Matching

The Spring Box is available in five force variants.
The main difference lies in the thickness of the spring strip.

Example: 0.09 × 16 × 2000

Thickness: 0.09 mm
Width: 16 mm
Length: 2000 mm

Thicker springs provide higher lifting force
but allow fewer wraps within the Spring Box,
resulting in a shorter maximum blind drop.

Thinner springs support longer blind heights
with lower lifting force,
making proper selection essential for optimal performance.

Cordless Lift Control Selection Guide

Proper spring selection is critical for achieving balanced operation,
stable holding, and long service life.
The table below provides a general reference for matching spring specifications
to blind weight and drop length.

Fabric length/inch Spring Spec./mm	26″	36″	48″	54″	60″	64″	72″	84″	96″	104″	Top rebound force	Unit
0.07161999	136	150	167	175	183	189	200	217	233	244	50	g
0.08161999	189	205	223	232	241	247	259	277	295		75	g
0.09162000	263	288	317	332	346	356	376				100	g
0.10162000	333	365	404	423	442	455	481				125	g
0.11162000	444	480	524	546	567	582					175	g

Note: Spring selection should always consider fabric weight,
bottom rail weight, tube diameter, and target user pull force.
Final validation through prototype testing is recommended.

Integrated Brake System

The Brake is responsible for controlling movement and holding position.
It prevents sudden downward acceleration
and ensures the blind remains stable when released.

The brake does not generate lifting force;
instead, it governs motion within the force range defined by the spring.

Installation & Pre-Tensioning

Before insertion into the aluminum tube,the Cordless Lift Control must be pre-wound to store initial spring energy.

The Pin locks the spring after pre-tensioning,allowing safe handling during assembly.
Once installed, the Pin is removed,and the system becomes fully operational.

Applications

Residential roller blinds
Commercial window shading systems
Child-safe window coverings
Manual cordless roller blind platforms

Why Choose This Cordless Lift Control

Designed specifically for OEM roller blind manufacturers
Reduces safety compliance risk
Minimizes wear-prone external components
Supports scalable production with consistent performance

Frequently Asked Questions

1. What type of blinds is this Cordless Lift Control designed for?

This Cordless Lift Control is specifically designed for roller blinds
using a 32mm aluminum tube.
It is not intended for Roman shades, zebra blinds, or venetian blinds.

2. Is this a complete roller blind system?

No. This product is an internal lift mechanism and belongs to the
roller blind accessory category.
Fabric, tube, bottom rail, and brackets are supplied separately by the manufacturer.

3. How does the blind stay in position without cords?

Position holding is achieved through the balance between
the constant force spring inside the Spring Box
and the integrated Brake.
The spring provides lifting force,
while the Brake controls motion and prevents sudden movement.

4. Can one spring model fit all blind sizes?

No. Different blind weights and drop lengths require different spring forces.
Selecting the correct spring thickness is essential
to avoid excessive pull force or insufficient lift.

5. What happens if the spring force is too strong?

An oversized spring may cause the blind to rise too quickly,
increase pull resistance,
or reduce usable drop length due to limited wrap capacity.

6. What happens if the spring force is too weak?

An undersized spring may result in poor lifting performance,
difficulty holding position,
or increased load on the Brake.

7. Why is pre-tensioning required before installation?

Pre-tensioning stores initial energy in the spring,
ensuring balanced operation from the first use.
The Pin temporarily locks the spring during assembly for safety and accuracy.

8. Is this system child-safe?

Yes. The Cordless Lift Control eliminates external cords and chains,
significantly reducing entanglement risks
and supporting modern child-safety requirements.

9. Can this system be used for very wide roller blinds?

Performance on wide blinds depends on proper spring selection,
fabric weight distribution,
and overall system design.
Wide applications may require careful testing and validation.

10. Do you support OEM customization?

Yes. Spring force configuration, component matching,
and packaging can be adjusted to support OEM manufacturing requirements.

Field Insight

The Cordless Lift Control is not simply a spring.
It is a balanced mechanical system where
spring force, brake resistance, and pre-tensioning
must work together.

Spring thickness determines both force and usable height
Brake stability is critical for safety and holding
Accurate pre-tensioning directly affects user experience
Proper load matching reduces long-term drift and noise