Tensioning apparatus for a web threading endless rope

• US 5,379,932 A
• Filed: 11/22/1993
• Issued: 01/10/1995
• Est. Priority Date: 10/28/1991
• Status: Expired due to Term

• Current Assignee: Paperchine Incorporated (Andritz AG)
• Original Assignee: Wespatt, Inc.
• Inventors: Bracken, Kenneth L.
• Primary Examiner(s): Crowder, Clifford D.
• Assistant Examiner(s): CALVERT, JOHN JAMES
• Application Number:
  US08/155,211
• Time in Patent Office: 414 Days
• Field of Search: 226/91, 226/92, 226/44, 226/195, 226/118, 226/119, 226/25, 474/104, 474/110, 474/136, 474/137
• US Class Current: 226/92
• CPC Class Codes: D21G 9/0072 using at least one rope

Abstract

A compact rope stretcher maintains the tension in an endless rope used for threading a web in a papermaking machine and includes an elongated H-beam having a flange engaged by guide wheels supporting a pair of separate carriages. The carriages support corresponding rope sheaves for free rotation, and a pair of fluid cylinders are mounted on opposite sides of the beam web and have piston rods connected directly to the corresponding carriages by laterally floating links. Proximity sensors are mounted on opposite end portions of the H-beam for indicating when the rope stretch is reaching a limit, and the beam supports a full length cover which encloses and protects the carriages and cylinders.

Claims

1. Apparatus for tensioning an endless rope used for threading a web in a papermaking machine and for taking up stretch which develops in the rope over a period of use, comprising a frame including an elongated beam having longitudinally extending and outwardly projecting opposite flange portions, said beam also including means projecting laterally from said flange portions for reinforcing said flange portions and to provide said flange portions with substantial rigidity, at least one carriage including a base member disposed adjacent and substantially parallel to said flange portions, a set of guide members mounted on said base member and engaging said opposite flange portions with said flange portions extending between said guide members to support said carriage for longitudinal movement along said beam, power operated means extending longitudinally of said beam and connected to said carriage for moving said carriage along said flange portions, and a guide sheave supported by said base member for free rotation and positioned to engage the rope.

2. Apparatus as defined in claim 1 wherein said beam comprises a pair of parallel spaced flanges integrally connected by a web, and at least one of said flanges includes said opposite flange portions.

3. Apparatus as defined in claim 1 wherein said base member comprises a generally flat carriage plate, and said guide members are mounted on said carriage plate adjacent said flange portions.

4. Apparatus as defined in claim 1 wherein said means connecting said piston rod to said carriage comprise a laterally projecting link member secured to said carriage, and means providing for laterally floating movement of said link member relative to said piston rod.

5. Apparatus as defined in claim 1 and including sensor means supported by said beam for sensing the longitudinal position of said carriage on said beam for indicating the extent of stretch in the rope.

6. Apparatus as defined in claim 1 wherein a second said carriage is supported by another set of said guide members engaging said flange portions, said second carriage supporting a second sheave for free rotation, and second power operated means extending longitudinally of said beam and connected to said second carriage for moving said second carriage.

7. Apparatus adapted for tensioning an endless rope used for threading a web in a papermaking machine and for taking up stretch which develops in the rope over a period of use, comprising a frame including an elongated beam having longitudinally extending and outwardly projecting opposite flange portions, said beam also including a longitudinally extending portion projecting laterally from said flange portions for reinforcing said flange portions, at least one carriage including a base member disposed adjacent and substantially parallel to said flange portions, a set of guide members mounted on said base member and engaging said opposite flange portions with said flange portions extending between said guide members to support said carriage for longitudinal movement along said beam, at least one elongated fluid cylinder extending longitudinally of said beam and having a piston rod movable longitudinally of said beam, means for securing said cylinder to said beam, means for connecting said piston rod to said carriage and providing for movement of said carriage along said flange portions in response to actuation of said cylinder, and a guide sheave supported by said base member for free rotation and positioned to engage the rope.

8. Apparatus as defined in claim 7 wherein said beam comprises a pair of parallel spaced flanges integrally connected by a web, and at least one of said flanges includes said opposite flange portions.

9. Apparatus as defined in claim 7 wherein said base member comprises a generally flat carriage plate, and said guide members are mounted on said carriage plate adjacent said flange portions.

10. Apparatus as defined in claim 7 wherein said means connecting said piston rod to said carriage comprise a laterally projecting link member secured to said carriage, and means providing for laterally floating movement of said link member relative to said piston rod.

11. Apparatus as defined in claim 7 and including sensor means supported by said beam for sensing the longitudinal position of said carriage on said beam for indicating the extent of stretch in the rope.

12. Apparatus as defined in claim 7 wherein a second said carriage is supported by another set of said guide members engaging said flange portions, said second carriage supporting a second sheave for free rotation, a second said fluid cylinder extending longitudinally of said beam and having a corresponding said piston rod, and second said means connecting said piston rod of said second fluid cylinder directly to said second carriage.