All-composite torque tube with metal eyelets

Patent metadata

Field	Value
Publication number	US-9937671-B2
Application number	US-201614996922-A
Country	US
Kind code	B2
Filing date	Jan 15, 2016
Priority date	Jan 15, 2016
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A low-cost method of manufacturing an all-composite composite torque tube includes winding fiber tow around a cylindrical mandrel and a plurality of eyelet forms held by an end fixture on the mandrel, whereby a flanged end coupling is formed. The method may include the use of a pre-woven composite fiber end sleeve configured to define the flanged end coupling. The wound fiber, and the end sleeve, are cured together in a single step. Metal eyelets may be installed in the bolt holes.

First claim

What is claimed is:

1. A method of manufacturing a composite torque tube, the method comprising the steps of:
providing a cylindrical mandrel;
positioning an end fixture on the mandrel, the end fixture including a backing surface radially enlarged relative to an outer surface of the mandrel and a plurality of openings through the backing surface;
inserting a plurality of eyelet forms respectively into the plurality of openings of the end fixture, wherein the eyelet forms extend parallel to an axial direction of the cylindrical mandrel;
winding a fiber tow around the mandrel and the plurality of eyelet forms;
infusing the wound fiber tow with a resin matrix, or using fiber tow pre-impregnated with a resin matrix in a B cure stage as the fiber tow for the winding step;
curing the wound fiber tow to a C cure stage, thereby yielding a composite tube including an integral end flange having a plurality of axially extending bolt holes; and
removing the eyelet forms, the end fixture, and the mandrel from the composite tube after the steps of winding, infusing, and curing have been completed.

2. The method according to claim 1 , further comprising the steps of:
providing a woven end sleeve including an axially extending stem, a radially enlarged flange layer at a distal end of the stem, a passage through the flange layer and the stem for receiving an end portion of the mandrel, and a plurality of bolt holes through the flange layer;
placing the end sleeve on the mandrel such that the flange layer of the end sleeve is in abutment against the backing surface of the end fixture, wherein the plurality of eyelet forms are inserted respectively through the plurality of bolt holes of the end sleeve and into the plurality of openings of the end fixture; and
infusing the end sleeve with a resin matrix, or using fiber tow pre-impregnated with a resin matrix in a B cure stage to weave the end sleeve;
wherein the winding step includes winding the fiber tow around the stem of the end sleeve;
wherein the curing step includes curing the end sleeve to a C cure stage along with the wound fiber tow.

3. The method according to claim 1 , further comprising the step of installing a plurality of metal eyelets respectively in the plurality of bolt holes of the integral end flange.

4. The method according to claim 2 , further comprising the step of installing a plurality of metal eyelets respectively in the plurality of bolt holes of the integral end flange.

5. A composite torque tube manufactured by the method of claim 1 .

6. A method of manufacturing a composite torque tube, the method comprising the steps of:
providing a cylindrical mandrel;
positioning an end fixture on the mandrel, the end fixture including a backing surface radially enlarged relative to an outer surface of the mandrel and a plurality of openings through the backing surface;
inserting a plurality of eyelet forms respectively into the plurality of openings of the end fixture;
winding a fiber tow around the mandrel and the plurality of eyelet forms, wherein the step of winding the fiber tow includes, in ordered sequence:
helically winding the fiber tow around the mandrel and the stem of the sleeve in an axial direction toward the flange layer;
winding the fiber tow partially around a first one of the eyelet forms;
winding the fiber tow partially around a second one of the eyelet forms and back to the stem of the sleeve such that the fiber tow leaving the second eyelet form crosses the fiber tow approaching the second eyelet form when viewed in the axial direction toward the flange layer; and
helically winding the fiber tow around the stem and the mandrel in an axial direction away from the flange layer;

infusing the wound fiber tow with a resin matrix, or using fiber tow pre-impregnated with a resin matrix in a B cure stage as the fiber tow for the winding step;
curing the wound fiber tow to a C cure stage, thereby yielding a composite tube including an integral end flange having a plurality of bolt holes; and
removing the eyelet forms, the end fixture, and the mandrel from the composite tube.

7. The method according to claim 6 , wherein the fiber tow has an outer tangential approach to the first one of the eyelet forms and an inner tangential approach to the second one of the eyelet forms.

8. A method of manufacturing a composite torque tube, the method comprising the steps of:
providing a cylindrical mandrel;
providing a woven end sleeve including an axially extending stem, a radially enlarged flange at a distal end of the stem, a passage through the flange and the stem for receiving an end portion of the mandrel, and a plurality of bolt holes extending axially through the flange;
placing the end sleeve on a mandrel;
winding a fiber tow around the mandrel and the stem of the end sleeve;
infusing the wound fiber tow and the end sleeve with a resin matrix, or using fiber tow pre-impregnated with a resin matrix in a B cure stage as the fiber tow for the winding step and to weave the end sleeve;
curing the fiber tow and the end sleeve to a C cure stage, thereby yielding a composite tube including an integral end flange having a plurality of axially extending bolt holes; and
removing the mandrel.

9. The method according to claim 8 , further comprising the step of positioning a plurality of metal eyelets respectively in the plurality of bolt holes of the end sleeve prior to the step of curing.

10. The method according to claim 8 , wherein the step of winding the fiber tow includes, in ordered sequence:
helically winding the fiber tow around the mandrel and the stem of the end sleeve in an axial direction toward the flange of the end sleeve; and
helically winding the fiber tow around the stem of the end sleeve and the mandrel in an axial direction away from the flange of the end sleeve.

11. A composite torque tube manufactured by the method of claim 8 .

Assignees

• Moog Inc

Inventors

• Larson Lowell Van Lund

Classifications

• B29C70/222

  the structure being shaped to form a three dimensional configuration · CPC title

• F16C3/026

  Shafts made of fibre reinforced resin · CPC title

• B29K2105/0872

  Prepregs · CPC title

• B29L2031/75

  Shafts · CPC title

• B29L2031/3076

  Aircrafts (blades, propellers B29L2031/08) · CPC title