Apparatus for manufacturing tubes

In an apparatus for producing a tube from a continuous strip travelling at a first velocity by helically coiling said strip into a continuous plurality of convolutions comprising,

• a. an apparatus body,
• b. connecting means adapted to receive said continuous strip and join an edge portion thereof with an adjacent edge portion of a just formed convolution into a joint, said means including an inner and outer connecting roller rotatively carried by said body to intersect tangentially with an inner and outer peripheral surface of said tube, and
• c. driving means connected to said connecting rollers to drive said rollers at peripheral velocities differing from said first velocity of said strip and a rotational velocity of said convolutions.
• wherein characteristics of said joint are controlled in relation to a magnitude of said velocity differences.

An apparatus for forming a tube by continuously coiling into a helical convolution a metal strip having longitudinal corrugations comprising:

• an apparatus structure,
• guide means to direct said strip into said apparatus,
• a vertical support plate carried by said structure and obliquely aligned with the longitudinal axis of said strip, coiling means carried by said plate and including,
• an inner connecting roller and an outer connecting roller rotatively carried by and positioned transversely to a vertical axis of said plate and spaced to provide an opening for said strip and said convolution and join said strip to said convolution in a fixed relationship,
• a plurality of rotatable guide rollers on said plate to guide said convolution, said guide rollers having axes forming a circle with said inner and outer connecting rollers positioned on said plate tangentially to said circle, and
• a source of rotary power operatively connected to said connecting rollers and driving said rollers to have peripheral surface velocities differing from a velocity of said strip and said convolution in contact therewith.

An apparatus for producing a tube from a strip by the continuous helical coiling of said strip in a plurality of joined convolutions comprising,

• a. an apparatus body,
• b. means carried by said body for joining an inner surface portion of said strip to an outer surface portion of a just formed convolution, said means including inner and outer connecting rollers having parts in contact with said strip and said just formed convolution, and
• c. driving means connected to said connecting rollers to drive said rollers at peripheral velocities differing from a longitudinal velocity of said strip and a rotational velocity of said convolutions,
• wherein said tube is formed having a tight joint between adjacent convolutions and said convolutions are constant in diameter.

An apparatus for producing a tube from a continuous corrugated strip by coiling said strip into convolutions and joining adjacent edges of said incoming strip and said convolutions comprising,

• a. an apparatus body,
• b. an inner connecting roller including a first and second roller part, said first roller part rotatively carried on an inner drive shaft of said apparatus body and said second roller part fixedly carried on said shaft, said first and second roller parts having a series of circumferent grooves formed with an apex and a groove bottom,
• c. a circular hooking disk having a series of outwardly projecting camming projections and being rotatively carried in an annular space in said second roller part of said inner connecting roller,
• d. an outer connecting roller including a first and second roller part being fixedly carried by an outer drive shaft of said apparatus body, said first and second roller parts having a series of circumferent grooves formed with an apex and a groove bottom and said grooves positioned to have said apex align with said groove bottom of said inner connecting roller grooves,
• e. a flattened groove formed in said second roller part of said outer connecting roller and positioned to align with said disk and provide a support surface for said camming projections of said disk, and
• f. driving means operatively connected to said inner and outer drive shafts to rotate said shafts at varying rotational velocities,
• wherein a diameter of said formed tube is regulated as a function of said rotational velocity of said inner and outer drive shafts and said camming projections form a hooking joint between said edges of said incoming strip and said adjacent convolution.