Conveyors, Pneumatics & Equipment Handshakes

Cell equipment must agree on who owns the part, who may move, and what completion means. A handshake is a small protocol, not a handful of unlabeled bits.

A robust transfer sequence

Downstream asserts Ready when space, mode, and health permit. Upstream asserts TransferRequest with a part available. After Ready and Request, motion begins. A sensor confirms the part left upstream; another confirms it arrived downstream. Both sides update ownership and clear signals in a defined order.

Specify response timeout, part-travel timeout, cancellation, duplicate request, sensor disagreement, blocked zone, restart after power loss, and manual disposition. Sequence numbers or explicit part IDs can prevent a stale completion from being attached to the next part.

Conveyor fundamentals

Check product stability, accumulation pressure, friction variation, incline, acceleration, side guides, transfers, pinch points, guarding, and jam access. Motor sizing includes belt/chain tension, rolling/sliding resistance, product mass, acceleration, efficiency, and starting or jam cases. Throughput is limited by spacing and downstream service, not only belt speed.

Pneumatic functions

Use flow controls to manage speed, pressure regulation for appropriate force, and end-of-stroke cushioning where needed. Put sensors where they prove the intended state. Define exhaust, trapped energy, gravity, and restart behavior. A closed valve can trap hazardous pressure; OSHA lockout/tagout addresses electrical, mechanical, hydraulic, pneumatic, chemical, thermal, and other stored energy during service ¹.

Recovery is physical work

Design access, visibility, removable covers, purge or reject paths, and controls for bounded recovery. Do not create a cell that requires reaching through a sensor field every tenth cycle.

Interface control document

Produce a table for two pieces of equipment: signal, direction, meaning, assertion rule, clearing rule, timeout, failure response, restart state, and test case. Draw the physical part zones beside the signal sequence so data ownership matches material ownership.