Precision Anti-backlash Shaft Differentials

Product Announcement from Stock Drive Products & Sterling Instrument - SDP/SI

Hicksville, NY -- Precision shaft differentials manufactured by SDP/SI, feature built-in anti-backlash characteristics for eliminating play in shaft rotations. Identified as part number S9540A-TS9, the differential provides a high level of precision in instrument drives and is particularly effective at adding and subtracting shaft rotations in servo systems.

The patented unit (No. 3,137,181) consists of three stainless steel bevel gears mounted to a central spider block. Sterling Instrument will assemble any end gears ordered with the differential for no extra charge.

Specifications of the S9540A-TS9 anti-backlash differential are:

• Nominal shaft diameter: .125 in.
• Maximum load rating: 50 oz. in.
• Maximum operating speed: 1000 rpm
• Breakaway torque (one-tooth load): .15 oz. in.
• Breakaway torque (three-tooth load): .30 oz. in.
• Weight: 1.8 oz.

Compared to a maximum backlash of 10 minutes between end gears when using a standard differential, the S9540A-TS9 unit ensures zero backlash within the rated torque and speed.

SDP/SI is a leading manufacturer of small mechanical components, servicing a wide variety of aerospace, medical and commercial industries for over 50 years. Quotes, online orders, and 3D CAD Models are available on our updated estore at SDP/SI offers over 120,000 small mechanical components, including gears, belt and chain drives, shafts, shaft accessories, bearings, couplings, universal joints, vibration mounts, miscellaneous components, hardware, gearheads and speed reducers, right angle drives, brakes and clutches, motors and gearmotors. For additional information about SDP/SI, please visit

Stock Drive Products / Sterling Instrument (SDP/SI), 250 Duffy Avenue, Hicksville, NY 11801. Phone: 1-800-819-8900 | 516-328-3300 • Fax: 516-326-8827.