DJ-S Double Star Elastic Coupling | 20-4800 N·m, 19000 RPM

PRODUCTS

CONTACT US

DJ-S Double Star Elastic Coupling | Zero Backlash, High Misalignment Compensation

Model Number
Check below, custom

DJ19S

DJ24S

DJ28S

DJ38S
DJ42S

DJ48S

DJ55S

DJ65S

DJ75S

DJ90S

Product Description

DJ-S Double Star Elastic Coupling – Zero Backlash, High Misalignment Compensation for Demanding Drives

The Apexcoupling DJ-S series is a high-performance double star elastic coupling engineered for demanding motion control applications that require superior misalignment compensation and zero-backlash torque transmission. Featuring a dual elastomer (double star) design with two star-shaped polyurethane elements, this coupling provides exceptional compensation for angular, radial, and axial misalignment. The two-part, two-section structure can compensate for large installation deviations, damping vibration and reducing noise. With zero backlash operation, maintenance-free polyurethane elastomers, and axial plug-in installation, the DJ-S series is the ideal solution for main spindle drives, lifting platforms, machine tools, servo motors, and general industrial machinery.

✅ Zero backlash for precise positioning. Dual star elastomer design for superior misalignment compensation. Compensates angular, radial, and axial deviations. Maintenance-free – no lubrication required. Axial plug-in installation for easy assembly. High load capacity and vibration damping.

Key Technical Specifications

Parameter	Value
Brand	Apexcoupling
Model Series	DJ-S (Double Star Elastic Coupling)
Type	Flexible / Star / Spider
Structure	Two hubs + two star-shaped polyurethane elastomers (dual element)
Hub Material	45# steel (standard); High-strength aluminum alloy (optional)
Surface Treatment	Natural, black oxide
Elastomer Material	High-strength polyurethane (PU) – wear-resistant, oil-resistant
Elastomer Hardness	98 Shore A (standard)
Backlash	Zero – no rotational clearance
Bore Tolerance	H7
Bore Diameter Range	6 – 100 mm (varies by model)
Outer Diameter Range	40 – 200 mm
Length Range	92 – 330 mm
Rated Torque	20 – 4800 N·m
Maximum Speed	3750 – 19000 RPM (varies by model)
Allowable Angular Misalignment	1.2° – 3.4° (varies by model)
Allowable Radial Misalignment	0.65 – 2.5 mm (varies by model)
Operating Temperature	-35°C to +80°C
Installation	Axial plug-in – easy assembly and disassembly
Lubrication	None required – maintenance-free
Customization	OEM – custom bores, keyways, and materials
Applicable Industries	Machine tools, lifting platforms, servo motors, main spindle drives, compressors, fans, pumps, general industrial machinery
Place of Origin	Guangdong, China

🔧 Custom bores, keyways, and special materials available. Contact us with your specifications.

DJ-S Series – Model Range & Specifications

Model	Rated Torque (N·m)	Max Speed (RPM)	D (mm)	Shaft Hole d (mm)	L (mm)	L1 (mm)	L2 (mm)	L0 (mm)	Allowable Radial Deviation (mm)	Allowable Angular Deviation (°)
DJ19S	20	19000	40	6–25	92	10	42	16	0.65	1.2
DJ24S	70	14000	55	8–35	112	16	52	18	0.89	1.4
DJ28S	190	11800	65	10–40	128	18	58	20	1.0	1.5
DJ38S	380	9500	80	12–48	158	20	68	24	1.15	1.8
DJ42S	530	8000	95	14–55	174	22	74	26	1.26	2.0
DJ48S	620	7100	105	15–60	192	24	80	28	1.36	2.1
DJ55S	820	6300	120	20–70	218	28	88	30	1.52	2.1
DJ65S	1250	5600	135	22–75	252	32	102	35	1.75	2.6
DJ75S	1940	4750	160	30–60	286	36	116	40	2.0	3.0
DJ90S	4800	3750	200	40–100	330	40	130	45	2.5	3.4

📐 Additional sizes and custom dimensions available upon request. Contact our engineering team for custom sizing.

Product Structure – Dual Elastomer (Double Star) Design

Two Hubs – Precision-machined from 45# steel or high-strength aluminum alloy with H7 bores.
Two Star-Shaped Polyurethane Elastomers – Dual elastomer elements串联 for superior misalignment compensation and vibration damping.
Axial Plug-in Design – Easy installation and removal without moving connected equipment.

💡 How it works: The DJ-S series consists of two hubs with two star-shaped polyurethane elastomers between them. The dual elastomer design provides significantly higher misalignment compensation than single-element designs, making it ideal for applications with large installation deviations. Power is transmitted through the elastomers, which flex to absorb shock, dampen vibration, and compensate for angular, radial, and axial misalignment. The zero backlash design ensures precise positioning, while the maintenance-free polyurethane elastomers require no lubrication.

Product Features & Advantages

Advantage	Benefit
Zero Backlash	No rotational clearance – precise positioning for servo motors and machine tools
Dual Elastomer (Double Star) Design	Superior misalignment compensation – handles large angular, radial, and axial deviations
Large Installation Deviation Compensation	The two-part, two-section structure can compensate for significant installation deviations
Vibration Damping & Noise Reduction	Polyurethane elastomers absorb shock and dampen vibration – extends equipment life
Maintenance-Free	No lubrication required – reduces operating costs
Axial Plug-in Installation	Easy assembly and disassembly – no special tools required
High Load Capacity	Handles demanding applications – up to 4800 N·m
Compact Design	Small radial dimensions – saves installation space
Wide Temperature Range	-35°C to +80°C – suitable for diverse environments
OEM Customization	Custom bores, keyways, and materials available

Applications

Main Spindle Drives – CNC machine tools, machining centers
Lifting Platforms – Scissor lifts, aerial work platforms
Machine Tools – Lathes, milling machines, grinding machines
Servo Motors – High-precision motion control systems
Compressors – Air and gas compressors
Fans & Blowers – Industrial ventilation systems
Pumps – Centrifugal, gear, and diaphragm pumps
General Industrial Machinery – Mixers, conveyors, agitators

Why Choose Apex Coupling for DJ-S Star Couplings?

Advantage	Description
Factory Direct	Competitive B2B pricing – no middlemen
Premium Materials	45# steel or aluminum alloy hubs + polyurethane elastomers
Dual Elastomer Design	Superior misalignment compensation – handles large deviations
Zero Backlash	Precision performance for servo motors and machine tools
Maintenance-Free	No lubrication required – reduces operating costs
Wide Model Range	DJ19S to DJ90S – covers most industrial applications
OEM Customization	Custom bores, keyways, and materials available

FAQ

Q: What is the advantage of the dual elastomer (double star) design?
A: The dual elastomer design provides significantly higher misalignment compensation than single-element designs, making it ideal for applications with large installation deviations. It also provides superior vibration damping and noise reduction.

Q: Does the coupling have backlash?
A: No. The DJ-S series features zero backlash – no rotational clearance, ensuring precise positioning for servo motors and machine tools.

Q: What materials are used?
A: The hubs are made of 45# steel or high-strength aluminum alloy. The elastomers are made of high-strength polyurethane (PU) with 98 Shore A hardness.

Q: Is the coupling maintenance-free?
A: Yes. The DJ-S series is maintenance-free – no lubrication required.

Q: What is the operating temperature range?
A: The operating temperature range is -35°C to +80°C.

Q: What are the common applications?
A: Main spindle drives, lifting platforms, machine tools, servo motors, compressors, fans, and pumps.

Q: Can I get a custom coupling?
A: Yes. We offer OEM customization – custom bores, keyways, and materials available.

Request a Quote

Send us your model (e.g., DJ38S), bore size, torque, speed, and application details. Our engineers will recommend the optimal model and provide a quotation within 24 hours.