Overview
The R+W EK7/20/B/19.05PFN/26 is a compact elastomer spider coupling engineered for precision power transmission in industrial automation and mechanical drive systems. This coupling combines two precision-machined aluminum hubs with a precision-molded elastomer insert to deliver backlash-free torque transmission while accommodating shaft misalignment and vibration isolation.
Key Features
- Expanding Shaft Design: One side features a clamping hub with screw (ISO 4762) and the other side has an expanding shaft with internally tapered clamping element, enabling rapid axial installation without lateral access holes.
- Precision Elastomer Insert: Precision-molded, wear-resistant, thermally stable polymer delivers vibration damping and electrical isolation between shaft components.
- Compact Axial Mounting: Short, compact design for easily mounted axial installation where space is restricted.
- Backlash-Free Performance: Long-term, backlash-free, vibration damping, electrically isolating solution for precision servo and motor-drive applications.
- Easy Assembly: Lateral access holes for screw tightening are not necessary. The unique assembly screw design allows for easy axial mounting and dismounting of the coupling hub.
Technical Specifications
- Model: EK7/20/B
- Part Number: EK7/20/B/19.05PFN/26
- Bore Size: 19.05 mm (0.75″)
- Coupling Type: Elastomer spider coupling with expanding shaft hub
- Hub Material: Aluminum (series up to 450)
- Elastomer Material: High-strength polyamide
- Connection Type: Expanding shaft clamping screw (ISO 4762)
- Electrical Property: Electrically isolating
- Balance Grade: G2.5 standard (G6.3 available on request)
Typical Applications
The EK7 has two coupling hubs that are concentrically machined with curved jaws, making it ideal for:
- Servo motor to lead screw assemblies
- Stepper motor drive shafts
- Precision pump and fan coupling
- Robotics and automation equipment
- Medical device drive systems
- Compact machinery with space constraints
Compatibility & Replacements
Compatible With
- ISO 4762 standard socket head cap screws
- 19.05 mm (0.75″) shaft diameters
- Expanding shaft clamping cone systems
- Direct motor-to-load drive configurations
Replaces / Drop-In Replacement For
This unit is a standard R+W EK7 series coupling configuration. Verify coupling compatibility with your system integrator before ordering, as bore diameters and shaft configurations vary by application.
Works With
- NEMA and IEC servo motors
- Stepper motors with metric shafts
- Precision gear reducers and gearheads
- Belt and chain drive systems
- Lead screw and ball screw assemblies
