Core Selling Points
· No keyway: torque is transmitted by friction, so there is no key backlash to hammer out under reversing loads.
· Set the pinion at any angle and axial position - useful when aligning a pinion to a rack or synchronising two drives.
· Releases by loosening the screws; no pulling, no damaged shaft.
· Helical teeth for quiet rack drives; hardened and ground options.
· Servo-driven rack axes on gantries and robot tracks
· Dual-pinion drives that must be phase-matched
· Reversing indexing drives
· Retrofits where the shaft has no keyway
A keyway is cheap but always has some clearance. On a reversing servo axis, that clearance turns into a small dead zone and, over time, a worn key and keyway. A keyless locking assembly avoids the problem: tightening the screws pulls tapered rings together, which expands them radially and presses on both shaft and hub.
The transmissible torque comes from friction on the shaft contact area: T = p x pi x d x L x mu x d / 2, where p is the contact pressure, d the shaft diameter, L the contact length and mu the friction coefficient. Torque rating therefore depends on correct screw torque and a clean, dry (or as specified) contact surface. Use the locking assembly maker's rated torque and screw tightening torque.
Because the pinion can be turned on the shaft before locking, the tooth can be aligned to the rack exactly, and in dual-pinion drives one pinion can be phased against the other to remove backlash.
| Item | Value |
| Gear type | Helical (spur available) |
| Module | To drawing (rack drive range M1-M10) |
| Material | 42CrMo, 20CrMnTi, C45 |
| Heat treatment | Q&T, induction hardened, or carburised and ground - to drawing |
| Shaft connection | Keyless locking assembly in hub (shaft diameter to drawing) |

Locking assembly: screws wedge taper rings between shaft and pinion hub
· Clean and degrease shaft and bore unless the locking assembly maker specifies otherwise.
· Position and align the pinion to the rack before tightening.
· Tighten screws gradually in a cross pattern to the specified torque, in several passes.
· Re-check screw torque after the first running period.
· Pinion and locking assembly supplied as one unit.
· Backlash-free shaft connection for servo axes.
· Pinion bore and locking assembly matched before shipping.
Applicable Industries
Automation and robotics, machine tools, gantry systems, packaging machinery.
For drawings, samples or a quotation, send us your rack, pinion or gear specification and quantity.