Vertical Spiral Conveyor

Overview

A vertical spiral conveyor moves product up or down between floor levels on a single continuous belt wound around a central column. Unlike a stack of inclined belts joined by transfers, the spiral carries each case, tote, or tray on one unbroken path, so nothing is dropped, tipped, or jammed at a transfer point. The machine fits a large change in height into a small floor area, which is why it shows up in distribution centres, bakeries, and bottling lines where a flat conveyor would need a long ramp.

The conveyor is built around a welded Helical Tower that sets the lift height and pitch, a Spiral Belt System that follows the helix, a Drive Station that pulls the belt, the Infeed and Outfeed Sections sections that hand product on and off, a Tension and Take-Up that keeps the long belt taut, and a Control Panel panel that runs the line.

The helical tower

The Helical Tower is the backbone. A heavy Center Column stands plumb on the Base Frame and carries a continuous Helical Guide Rail that defines the spiral path. Cantilevered Track Support Arm arms bolt to the column at fixed intervals and hold a ring of curved Curved Deck Section plates, one under each turn of belt. The pitch, the vertical rise per turn, is set by where these supports sit, and it is chosen so the incline never exceeds what the product will hold without sliding, usually below 15 degrees for loose cases. The base frame anchors the whole assembly to the slab with Anchor Plate plates and trims any floor slope out with Leveling Foot feet so each turn keeps even spacing.

How the belt curves

The hard problem in a spiral is making a belt go around a tight curve while staying flat enough to carry product. The Spiral Belt System solves it with a Sideflex Belt, a plastic modular belt assembled from hundreds of Belt Module links joined by Hinge Pin pins. The links are shaped so that on the inside of a curve they collapse and overlap, and on the outside they open out, which lets the belt fan around the helix while its top surface stays level. Each module carries a Edge Tab on its outer edge, and the drive grips these tabs to pull the belt up the spiral, a method that loads the strong outer edge rather than dragging the whole belt. The belt slides on a row of low-friction Wear Strip strips along each deck, and Inner Edge Guide and Outer Edge Guide rails keep both edges captured so product cannot drift off.

Drive and tension

The Drive Station usually sits at the top of the tower so it pulls the loaded belt rather than pushing it. An inverter-duty Helical Gearmotor turns a Drive Shaft carrying a Drive Sprocket Set set that meshes the belt edge tabs. A Torque Reaction Arm holds the gearbox steady against reaction torque. Because the belt is long and warms during a shift, it stretches, so the Tension and Take-Up keeps it taut: a spring-loaded Take-Up Roller on a Take-Up Slide adds or removes belt length automatically, and a Tension Sensor trips the drive if tension drifts out of range, which protects the belt from snapping or jumping the sprocket.

Infeed, outfeed, and materials

Product reaches the spiral on the Infeed Conveyor and leaves on the Outfeed Conveyor, both short flat belts that align the load and match its speed to the spiral. Fixed Dead Plate dead plates bridge the small gap at each handoff so a case never falls into it, and Side Guide rails center the load. Belt modules are moulded in POM acetal for dry goods or in FDA food grades for bakery and packaging lines, wear strips are UHMW polyethylene for low friction and long life, and the column and supports are painted structural steel, or stainless where washdown is required.

Control and accumulation

The Control Panel panel runs a Variable-Frequency Drive that ramps the Helical Gearmotor gently so product is not jolted on the curves, and a PLC that handles the line logic. A set of Photoeye sensors watches the infeed, the outfeed, and key points on the helix to detect jams and to signal when the downstream line is full, at which point the spiral can slow or stop so cases queue without crushing. The drive electronics share a Power Supply and report status to an LCD Panel operator screen.

Safety and use

Because the belt and sprockets present pinch and nip points, the Guarding and Safety wraps the tower in mesh Sheet Metal Panel panels, covers each Nip-Point Guard nip with a fixed shield, and fits Emergency Stop buttons within reach. An interlocked Access Gate stops the belt the moment it is opened for cleaning. Spiral conveyors come in two duties: a single-track unit that simply lifts or lowers a line between floors, and a wider accumulation spiral that uses the helix as a buffer to hold product during a downstream stoppage. Both run continuously and quietly, and because the helix has no transfers along its length they handle fragile and unstable loads, from bread trays to filled bottles, that would topple on a stepped incline.