Temporary clamp up system for sealant squeeze out in lock bolt installations

Patent metadata

Field	Value
Publication number	US-9644659-B2
Application number	US-201414215572-A
Country	US
Kind code	B2
Filing date	Mar 17, 2014
Priority date	Mar 17, 2014
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A joint fastening system employs a lock bolt having a pull stem and locking threads inserted through a bore in a joint having fay sealant between layers. A collar is received over the pull stem to engage the threads, the collar producing tension on the threads to generate clamp force sufficient for fay sealant squeeze out.

First claim

What is claimed is:

1. A joint fastening system comprising:
a lock bolt having a pull stem and locking threads inserted through a bore in a joint having fay sealant between layers;
a collar receivable over the pull stem without contact to engage the threads, said collar producing tension on said threads to generate clamp force sufficient for fay sealant squeeze out; and,
a sleeve insertable into said bore, said sleeve receiving said lock bolt with an expanding interference fit induced by rotational engagement of the collar on the threads drawing the lock bolt to 100% insertion depth.

2. The joint fastening system as defined in claim 1 wherein the collar comprises a removable nut internally threaded having a root of a predetermined thread form truncated such that the nut is received over the pull stem without contact and engages the locking threads.

3. The joint fastening system as defined in claim 2 further comprising a swage collar internally threaded having a root of a predetermined thread form truncated such that the swage collar is received over the pull stem and replaceably engaged on the locking threads.

4. A joint fastening system comprising:
a lock bolt having a pull stem and locking threads inserted through a bore in a joint having fay sealant between layers;
a collet clamp receivable over the pull stem without contact to engage the threads which is collapsible to engage the locking threads; and,
a retention ring received over a split sleeve to collapse the collet clamp, said collet clamp producing tension on said threads to generate clamp force sufficient for fay sealant squeeze out.

5. The joint fastening system as defined in claim 4 wherein the collet clamp further incorporates a drive element for rotating the split sleeve on the threads.

6. A joint fastening system comprising:
a lock bolt having a pull stem and locking threads inserted through a bore in a joint having fay sealant between layers;
an inner split sleeve receivable over the pull stem without contact to engage the threads and collapsible to engage the pull stem;
an intermediate sleeve tapered to collapse said inner sleeve upon translation;
a first drive element for translating the intermediate sleeve;
an outer sleeve engaging a surface of the joint upon axial translation; and,
a second drive element for translating the outer sleeve, said inner split sleeve producing tension on said threads to generate clamp force sufficient for fay sealant squeeze out.

7. The joint fastening system as defined in claim 6 wherein the first drive element is threaded to induce translation of the intermediate sleeve upon rotation.

8. The joint fastening system as defined in claim 6 wherein the second drive element is threaded to induce translation of the outer sleeve upon rotation.

9. A joint fastening system comprising:
a lock bolt having a pull stem and locking threads inserted through a bore in a joint having fay sealant between layers; and
a swage collar having a hex drive head frangible at a neck to receive a lock bolt collar swage die for swaging, said swage collar incorporating truncated threads received over the pull stem and engaging the locking threads, said swage collar producing tension on said threads to generate clamp force sufficient for fay sealant squeeze out.

10. The joint fastening system as defined in claim 9 wherein the drive element comprises a twelve point drive integral to a surface of the collar at a tip and recessed therefrom.

11. The joint fastening system as defined in claim 9 wherein the drive element comprises a twelve point drive integral to a surface of the collar adjacent an engagement flange of the collar.

12. A fastener comprising:
a lock bolt having a pull stem and locking threads inserted through a bore in a joint; and,
a collar having threads truncated radially at a root of the thread with a predetermined depth for a minor diameter to be received over the pull stem but engage the threads and having a drive element frangible at a predetermined torque configured to provide a temporary clamp-up tension force.

13. The fastener as defined in claim 12 wherein the collar threaded onto the lock bolt produces sufficient clamp-up tension to provide squeeze out of sealant between layers of a laminate.

14. The fastener as defined in claim 12 wherein the collar is swagable upon fracture of the drive element.

15. The fastener as defined in claim 12 wherein the pull stem of the lock bolt includes an anti-rotation feature.

16. The fastener as defined in claim 15 wherein the anti-rotation feature is selected from the group consisting of a machined flat, a hex head and a slot.

17. A method of installing a fastener system comprising:
inserting a lock bolt having a pull stem and locking threads through a bore in a joint having fay sealant between layers;
receiving a collar over the pull stem to engage the locking threads, said collar having threads truncated radially at a root of the thread with a predetermined depth for a minor diameter to be received over the pull stem but engage the threads and having a drive element frangible at a predetermined torque configured to provide a temporary clamp-up tension force,
producing tension with the collar on said locking threads to generate clamp force sufficient for fay sealant squeeze out.

18. The method of claim 17 wherein the step of receiving a collar over the pull stem comprises:
collapsing a split sleeve onto the locking threads;

and said step of producing tension comprises:
rotating the split sleeve with a drive element.

19. The method of claim 18 further comprising:
removing the split sleeve from the locking threads;
inserting a swage collar onto the lock bolt; and,
swaging the swage collar to secure the lock bolt.

20. The method of claim 17 wherein the step of receiving a collar over the pull stem comprises:
collapsing a split sleeve onto the locking threads;
and said step of producing tension comprises:
translating an intermediate sleeve tapered to collapse said split sleeve with a first drive element; and
axially translating an outer sleeve with a second drive element to engage a surface of a laminate.

21. The method of claim 20 further comprising:
translating the intermediate sleeve to remove the split sleeve from the locking threads;
inserting a swage collar onto the lock bolt; and,
swaging the swage collar to secure the lock bolt.

22. The method of claim 17 wherein the collar is a removable nut and the step of receiving a collar over the pull stem comprises:
engaging the locking threads with a predetermined thread form truncated such that the nut is received over the pull stem and engages the locking threads.

23. The method of claim 22 further comprising
removing the collar from the locking threads;
inserting a swage collar onto the lock bolt; and,
swaging the swage collar to secure the lock bolt.

24. The method of claim 17 wherein the step of receiving a collar over the pull stem comprises:
engaging the locking threads with a predetermined thread form truncated such that the collar is received over the pull stem and engages the locking threads; and,
torqueing a frangible drive element on the collar to a predetermined torque severing the drive element from the collar.

25. The method of claim 17 further comprising swaging the collar to secure the lock bolt.

Assignees

• Boeing Co

Inventors

• Woods Mark A
• Davies John A
• Shish Gregory J
• Chan Kwok Tung
• Avakian Eric M
• Day Dan
• Pacheo Agosto Omar J

Classifications

• F16B19/109

  Temporary rivets, e.g. with a spring-loaded pin (special clamping devices for workpieces to be riveted together, e.g. operating through the rivet holes B21J15/42; hand tools for temporarily connecting sheets before or during assembly operations B25B31/005) · CPC title

• F16B19/008

  with sealing means · CPC title

• Y10T29/49966

  with supplemental joining · CPC title

• F16B19/05 Primary

  Bolts fastening by swaged-on collars (F16B19/08 takes precedence) · CPC title

• Y10T29/49908

  Joining by deforming · CPC title