A helical conveyor for conveying piece goods comprises a frame and an endless conveyor belt which is drivable with respect to the frame along a helical track which extends about a centerline. The conveyor belt comprises discrete supporting members each comprising a substantially rigid slat and a roller. The slats follow a first helical path including a first inclination angle along the first helical path with respect to a base plane extending perpendicularly to the centerline and a second helical path including a second inclination angle along the second helical path with respect to the base plane. Each of the rollers is mounted to the corresponding slat such that the difference of an angle between the rolling direction and the base plane and the second inclination angle is smaller than the difference between the first and second inclination angles.

A conveyor comprises a helical conveying path having an upright central axis, a frame and an endless conveying member for transporting a product through the conveying path which conveying member is displaceable with respect to the frame. In a central portion of the conveying path, as seen in radial direction from the central axis, the conveying member is provided with an upwardly directed supporting surface for supporting a product. The width of the supporting surface in radial direction from the central axis is smaller than 10% of the distance between the central axis and the supporting surface. At opposite sides of the supporting surface the conveying path is free from obstacles at the height level of the supporting surface. The conveyor is provided with a helical guide for guiding the conveying member along the guide.

A conveyor comprises a helical conveying path having an upright central axis, a frame and an endless conveying member for transporting a product through the conveying path which conveying member is displaceable with respect to the frame. In a central portion of the conveying path, as seen in radial direction from the central axis, the conveying member is provided with an upwardly directed supporting surface for supporting a product. The width of the supporting surface in radial direction from the central axis is smaller than 10% of the distance between the central axis and the supporting surface. At opposite sides of the supporting surface the conveying path is free from obstacles at the height level of the supporting surface. The conveyor is provided with a helical guide for guiding the conveying member along the guide.

A helical conveyor comprises a belt having a transport section for transporting products where the belt follows at least partly a helical path between a lower end and an upper end of the transport section and a return section where the belt follows a path. The conveyor comprises a lower end reverse guide for turning the belt upside down and reversing its direction of movement between the transport section and the return section at the lower end of the transport section and an upper end reverse guide for turning the belt upside down and reverting its direction of movement between the transport section and the return section at the upper end of the transport section. The return section leaves the upper end through a horizontally oriented upper return section portion and the return section leaves the lower end through a horizontally oriented lower return section portion.

A helical conveyor comprises a belt having a transport section for transporting products where the belt follows at least partly a helical path between a lower end and an upper end of the transport section and a return section where the belt follows a path. The conveyor comprises a lower end reverse guide for turning the belt upside down and reversing its direction of movement between the transport section and the return section at the lower end of the transport section and an upper end reverse guide for turning the belt upside down and reverting its direction of movement between the transport section and the return section at the upper end of the transport section. The return section leaves the upper end through a horizontally oriented upper return section portion and the return section leaves the lower end through a horizontally oriented lower return section portion.

A freezing spiral net chain structure includes a plurality of chain links successively arranged in a travelling direction of a rail. Transmission teeth are arranged at inner ends of the chain links. Engagement teeth are arranged at two sides of the chain links. The engagement teeth of the adjacent chain links are engaged with each other. Axial holes are disposed between the mutually engaged engagement teeth. Rotary shafts are inserted into the axial holes. A metal piece is connected between outer ends of every two adjacent rotary shafts. The metal piece may bear a load from an outer-end spiral net, and since a coefficient of expansion of metal is smaller than that of plastic, deformation between the adjacent rotary shafts as a result of cold shrinking is reduced. The metal piece is different from the rotary shafts of the plastic spiral conveying net chain in terms of pitch.

A spiral conveyor system may include a cage associated with a motor; a conveyor belt traveling helically about the cage; the cage including a plurality of drive elements formed of vertically oriented cage bars; a cage bar cap mounted on at least one of the cage bars; the cage bar cap including a vertically oriented rib extending radially from a surface of the cage bar cap; wherein the rib includes at least one drive face; wherein the conveyor belt includes at least one belt surface configured to engage the at least one drive face; wherein the cage includes a ring that extends between the terminus of the rib and the entrance end of the cage; wherein the surface of the cage bar cap from which the rib extends defines a first diameter; and wherein the ring has a ring diameter that is larger than the first diameter.

A spiral conveyor system may include a cage associated with a motor; a conveyor belt traveling helically about the cage; the cage including a plurality of drive elements formed of vertically oriented cage bars; a cage bar cap mounted on at least one of the cage bars; the cage bar cap including a vertically oriented rib extending radially from a surface of the cage bar cap; wherein the rib includes at least one drive face; wherein the conveyor belt includes at least one belt surface configured to engage the at least one drive face; wherein the cage includes a ring that extends between the terminus of the rib and the entrance end of the cage; wherein the surface of the cage bar cap from which the rib extends defines a first diameter; and wherein the ring has a ring diameter that is larger than the first diameter.

A direct-drive spiral conveyor and a method for operating a spiral conveyor in which a sideflexing conveyor belt is positively driven in a helical path about the periphery of a rotating cylindrical drive drum. Parallel drive members extend in length along the periphery from the top to the bottom of the drive drum. The drive members engage drive faces on the inside edge of the conveyor belt and positively drive the inside edges along the helical path. The helical path is steeper at the entrance end—the bottom in an upgoing spiral, the top in a downgoing spiral—than at the opposite exit end and along a majority of the path.

A direct-drive spiral conveyor and a method for operating a spiral conveyor in which a sideflexing conveyor belt is positively driven in a helical path about the periphery of a rotating cylindrical drive drum. Parallel drive members extend in length along the periphery from the top to the bottom of the drive drum. The drive members engage drive faces on the inside edge of the conveyor belt and positively drive the inside edges along the helical path. The helical path is steeper at the entrance end—the bottom in an upgoing spiral, the top in a downgoing spiral—than at the opposite exit end and along a majority of the path.