Apparatus for fabricating drip irrigation tape

Patent 4722759 Issued on February 2, 1988. Estimated Expiration Date:

March 1, 2005. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Flow control devices particularly useful for drip irrigation
Patent #: 4173309
Issued on: 11/06/1979
Inventor: Drori

Apparatus for drip irrigation
Patent #: 4413787
Issued on: 11/08/1983
Inventor: Gilead , et al.

Drip irrigation system employing flow regulation Patent #: 4473191
Issued on: 09/25/1984
Inventor: Chapin

Inventors

Assignee

Roberts; James C.

Application

No. 06/707451 filed on 03/01/1985

US Classes:

156/203, And edge-joining of one piece blank to form tube156/218, Hollow cylinder article156/244.15, Specific nonuniform lamina or article; e.g., netting or rib and groove, etc.156/244.25, Article or at least one lamina of nonuniform thickness or discontinuous156/466, Tube-making type239/542, CONDUIT OR NOZZLE ATTACHED IRRIGATION-TYPE DECELERATOR239/547DISTRIBUTOR OR NOZZLE IN CIRCUMFERENTIAL WALL OF FLEXIBLE SUPPLY LINE

Examiners

Primary: Simmons, David A.

Attorney, Agent or Firm

Brown, Martin, Haller & Meador

International Classes

B29C 51/18 (20060101)
B29C 51/22 (20060101)
B29C 53/00 (20060101)
B29C 53/48 (20060101)
B29C 59/06 (20060101)
B29C 59/02 (20060101)
B29C 67/00 (20060101)
A01G 25/02 (20060101)
B29D 23/00 (20060101)

Abstract

An apparatus is disclosed for fabricating drip irrigation tape from a water impervious polyethelene film. A shaping assembly with a water-cooled vacuum drum preforms a groove along one edge, a folding device folds the strip lengthwise to form a first conduit, and a sealing assembly with an electrically-heated heat sealing wheel joins the edges along opposite sides of the groove to form a seam in which the groove defines a secondary conduit that is resistant to deformation. Flat spots on a pair of outwardly-extending annular ribs around the circumference of the heat sealing wheel produce breaks in the seam for inlet ports and outlet ports.