Unfolding joint for satellite solar generators

• US 6,682,020 B2
• Filed: 10/09/2002
• Issued: 01/27/2004
• Est. Priority Date: 06/17/1999
• Status: Expired due to Fees

• Current Assignee: Astrium GmbH (Airbus SE)
• Original Assignee: Astrium GmbH (Airbus SE)
• Inventors: Janson, Jürgen
• Primary Examiner(s): Poon, Peter M.
• Assistant Examiner(s): HOLZEN, STEPHEN A
• Application Number:
  US10/266,579
• Publication Number:
  US 20030031505A1
• Time in Patent Office: 475 Days
• Field of Search: 244/131, 244/173, 244/1.R, 403/71, 403/102
• US Class Current: 244/172.6
• CPC Class Codes: B64G 1/222 for deploying structures between a stowed and deployed state
• CPC Class Codes: B64G 1/443 Photovoltaic cell arrays
• CPC Class Codes: Y10T 403/32155 Bearing component clamped to plate or side, e.g., bolted, etc.
• CPC Class Codes: Y10T 403/32409 Members locked in axial alignment

Abstract

A joint is provided for unfolding systems, e.g. for satellite solar generators that permits sufficiently large unfolding torque, low weight and small dimensions. A drive on one joint half acts on a small pulley to wind a cord on it. The other end of the cord is tautly connected to a large pulley that rotates on the hinge pin and is fixed to the second joint half. The large pulley rotates in the opposite direction of the small pulley when the cord is wound so that the second joint half folds away from the first joint half on the hinge pin into an unfolded state and is held In this state by a stop against the tension of the cord. The joint is used, for example, for unfolding joints for satellite solar generators that consist of two joint halves, a hinge pin and a drive.

Claims

1. A satellite solar generator assembly comprising:

first and second joint parts connected with respective solar generator extension arms,

a hinge pin pivotally connecting the first and second joint parts,

a large pulley rotatably mounted at the hinge pin and fixed to the first joint part,

a small pulley disposed on the second joint part at a spacing from the larger pulley,

a cord partially wound on both the large and small pulleys, and a drive which in use operates to rotate the small pulley to wind the cord thereon, said cord being operable to rotate the large pulley and unfold the solar generator extension arms, wherein a ratio of a torque on the large pulley over a torque on the small pulley is equal to a ratio of the diameter of the large pulley over the diameter of the small pulley.

2. An assembly according to claim 1,

wherein the drive includes a spring member which can be triggered by telecontrol.

3. An assembly according to claim 1,

wherein the ratio of the sizes of the pulleys provides that less than one half of the torque required to unfold the joint part needs to be applied by the drive to the small pulley.

4. An assembly according to claim 1, wherein the ratio of the sizes of the pulleys provides that less than one half of the torque required to unfold the joint parts needs to be applied by the drive to the small pulley.

5. An assembly according to claim 2, wherein the spring member is configured to apply a substantially constant torque over the predetermined folding range of the joint part.

6. An assembly according to claim 4, wherein the predetermined folding range is 180°

.

7. An assembly according to claim 5, wherein the ratio of the sizes of the pulleys provides that less than one half of the torque required to unfold the joint halves needs to be applied by the drive to the small pulley.

8. An assembly according to claim 1, wherein the drive is a motor driven chain drive.

9. An assembly according to claim 1, wherein the drive is a motor driven toothed-belt drive.

10. An assembly according to claim 1, wherein the drive is a motor driven gear drive.