Circular Guide Conveyors are Precise and Practical

Recent years have seen an uptick in factory automation that combines conveying with assembly, testing, filling, and general material-handling tasks. These efficient arrangements require compact conveyance equipment to fit between workcell locations. Such installations also require accurate workpiece advancement. Two solutions here are belt-driven circular guide conveyors and linear-motor-driven linear-transfer systems. The latter is useful where the application needs the workpiece-bearing carriages (called pucks or pallets in some contexts) to independently advance on the conveyor line for variable distance between the carriages. However, most applications combining conveying with assembly can operate at top efficiency with fixed spacing between carriages. Here, circular guide conveyors excel as high-precision cost-efficient equipment.

Recent years have seen a proliferation of high-precision conveyor technologies that combine material handling and assembly of workpieces — especially workpieces that are relatively heavy or in need of precise transport. Rollon Nadella AXNR-series circular guide conveyors satisfy these requirements.

Circular guide conveyors join straight and curved track-roller linear guide sections in arrangements customized to end-user requirements. The conveyors satisfy an array of applications in the packaging and medical-device industries as well as other markets that must snake workpieces through multi-station assembly lines. Rollon Nadella AXNR-series conveyors are built around high-capacity FSR track-roller linear and curvilinear guides joined in a closed circuit. Drive and idler pulleys lead a synchronous belt along the path traced by the linear and curvilinear guides. Attached to the toothed belt (via fixed or flexible linkages) is a series of evenly spaced workpiece-bearing carriages. Curvilinear and track-roller linear guides: Rollon Nadella AXNR-series circular guide conveyors feature track-roller linear guide rails upon which the workpiece-bearing carriages ride. The carriage features an anodized aluminum body that can be machined and drilled to application-specific specifications; engineers can also specify carriages in corrosion-resistant and fully stainless-steel variations where needed. Both the linear guide tracks and the carriage track-roller wheels are constructed of stainless steel as standard.

Rollon Nadella AXNRO and ANXRQ circular guide conveyors can be customized to a vast array of dimensions.

In fact, the carriages feature track-roller wheels to bear loading in all directions. Two fixed and preloaded track-roller wheels ensure precise advancement of carriage-borne payloads around the circuit; that’s in contrast with traditional belt conveyors and even circular guide conveyors incorporating profile-rail ball linear guides. Then two eccentric track-roller wheels that ride the circuit’s inner guide rail allow for travel around turns and preloaded adjustment as needed. As they traverse the circuit, the carriage wheels pass through a Nadella LUBR station that uses oil-impregnated foam to wipe lubrication on the track-roller linear guide wheels and thus minimize the need for manual lubrication.

A Nadella LUBR station keeps the conveyor’s track-roller linear guide assembly lubricated. 

Belt assembly features: As mentioned, Rollon Nadella AXNR-series circular guide conveyors feature toothed belt drives to provide synchronous movement of the linear-guide-borne carriages. The quiet and maintenance-free synchronous belt drives are oriented with the flat backing vertical and facing outward to accept attachment of the system carriages; the belt teeth face inward to engage the system pulleys. Minimal distance from belt to carriages minimizes loading on fixed or floating linkages that affix the carriages to the belt through fixed or floating means — paramount where the carriage assemblies traverse transitions between curvilinear to straight circuit sections. In fact, floating linkages use rod ends to reliably advance carriages with the belt while also compensating for the way in which the distance between belt and carriages varies around curves.

Pulley assembly features: Rollon Nadella AXNR-series circular guide conveyors are pre- integrated with high-precision gearboxes (to which the drive pulley directly mounts) and an interface to simplify the attachment of the motor in the field. That said, design engineers can request that Rollon pre-integrate a gearbox of their choosing where needed.

Motor power is delivered to the conveyor drive pulley via a planetary right-angle or axial gearbox featuring reinforced bearings. The latter withstands the forces associated with belt tension to ensure precise conveyance.

Fully leveraging circular guide conveyor accuracy

A key strength of circular guide conveyors is the way in which they support discrete workpieces on rugged track-roller linear guides. Where design engineers aim to use these conveyors for demanding applications that need to hold workpieces extremely still at locations with repeatability to within hundredths of a millimeter — for delicate testing or assembly processes, for example — the circular guide conveyors can be fitted with position-locking indexing stations. Located on straight circuit sections, these use pneumatics to rotate a shaft studded with cams into and out of engagement with C-shaped receptacles (locating cam cutout) on the carriage bodies. This arrangement can be complemented by inductive proximity sensors if needed to verify carriage location and position-locked status if needed.

Connect with Rollon to identify design options

For more information on how to tailor Nadella AXNR conveyors to a specific application, visit this deep link on rollon.com. Or get help with identifying viable design solutions by gathering application objectives — including preferred drive type, necessary dimensions, carriage count and spacing, load and pace requirements — by contacting Rollon’s applications engineers.