Recent Blogs
Modified Two-Pawl Lever: Ideal Indexing
Explore a modified two-pawl lever that advances a ratchet one tooth on each half-stroke. Calculate ideal indexing rate and wheel speed from lever cycles and...
Lever to Slotted Rack via Two Hooked Pawls: How This Indexing Mechanism Works, Parts & Uses
See a driving pawl advance a slotted rack while a holding pawl retains each step. Calculate ideal cumulative travel from slot pitch and successful index...
Drop-and-Pawl Intermittent Rotation: Indexing Calculator | FIRGELLI
Compare star-wheel step angle, events per revolution and average event frequency. Brown movement 63 supplies the historical sequence; the current illustration does not solve contact...
Internal Geneva Drive: Index Angle and Dwell Calculator | FIRGELLI
Calculate index angle, accumulated output travel and motion/dwell intervals for an ideal internal Geneva. Explore the radial-slot and drive-pin motion.
Geneva Drive (external) Mechanism Explained: How It Works, Diagram, Parts, Formula & Uses
Geneva Drive explained — how the external Geneva mechanism converts continuous rotation into precise indexed motion for film projectors, turrets, and packaging lines.
Maltese Cross Mechanism: Exact External-Geneva Timing
Explore an external Geneva mechanism. Calculate output step, driver indexing angle and dwell time from slot count and constant driver speed.
Driving Wheel with Internal Rim Guard: How It Works, Parts, Formula & Diagram Explained
Explore a tappet and studded disk with an inner retaining rim. Adjust spacing, stud count and speed to calculate contact timing and output steps.
Driving Disk with Rim and Stops Mechanism Explained: How It Works, Parts, Formula & Uses
Explore a tappet and studded disk with an outer retaining rim. Adjust spacing, stud count and speed to calculate contact timing and output steps.
Crown-ratchet (rag-wheel) Mechanism Explained: How It Works, Parts, Diagram and Uses
Explore an axial crown ratchet and sliding pawl. Calculate nominal angle per click, total index, ramp slope and stop-face deviation, with a developed tooth profile.
Continuous Rotary to Intermittent via Cam and Disk: How It Works, Parts, Formula and Uses
Explore a stepped cam and two-stop disk. Adjust shaft offset, scale and input speed to calculate half-turn indexing and stationary intervals.
Cam to Double-rack Frame with Governor: Mechanism, How It Works, Parts, Uses & Formula
Explore a governor-selected double-ratchet frame driven by a rotating pin. Compare feed direction, advance per revolution and mean selected feed rate.
Bent-spring Driver with Strong-spring Catch: How the Mechanism Works, Parts, Formula, and Uses
Explore a bent spring on a rotating carrier engaging an intermittent ratchet through a fixed catch. Compare spring rates, preload and catch seating force.
Spur-gear Stops Mechanism: How It Works, Diagram, Formula, and Uses Explained
Spur-gear Stops limit rotation to a fixed number of turns in safes, winches, and counters. See how they work, the math, and real industrial examples.
Lantern-wheel Stops: Roller Clearance and Motion Calculator
See a roller arm release and arrest a lantern wheel. Compare arc pitch, straight trundle clearance and a circular stop’s geometric fit.
Intermittent Motion: Geneva Index and Dwell Calculator | FIRGELLI
Compare ideal Geneva step and index/dwell fractions, including an overlap warning for equally spaced pins. Physical multi-pin compatibility is not established.
Silent Ratchet (friction) Mechanism Explained: How It Works, Diagram, Parts, Formula and Uses
Silent Ratchet (friction) explained — how friction-grip pawls index loads without clicking, with worked examples from elevator hoists and rod-feed lathes.
Geneva Drive: External Indexing Geometry and Dwell Formula | FIRGELLI
Understand a standard external Geneva drive, calculate step angle and dwell time, and compare four-, six- and eight-slot timing with worked examples.