LIGHTWEIGHT COLLAPSIBLE DISH STRUCTURE AND PARABOLIC REFLECTOR EMBODYING SAME

• US 3,599,218 A
• Filed: 09/11/1968
• Issued: 08/10/1971
• Est. Priority Date: 09/11/1968
• Status: Expired due to Term

• Current Assignee: Clyde E. Williamson, Michael E. Bochory
• Original Assignee: Clyde E. Williamson, Michael E. Bochory
• Inventors: Williamson, Clyde E., Bochory, Michael E.
• Application Number:
  US04/759,136
• Time in Patent Office: 1,063 Days
• US Class Current: 343/840
• CPC Class Codes: H01Q 15/163 inflatable

Abstract

A collapsible lightweight, dish-shaped structure is provided for use as a parabolic reflector and other uses. The structure has a dish constructed of a lightweight, thin film membrane, such as an aluminized polymeric plastic film selected from the class including Mylar and Kapton. Lightweight elastic ribs or beams, which are preferably slender tubes constructed of the same thin film material as the dish, are bonded to the rear surface of the dish and are preformed to cause the dish to normally assume a predetermined geometric configuration, such as a parabolic shape. The structure may be folded for stowage in a container, or the like, in such a way that the structure, when released from the container, is deployed to its predetermined configuration by the elastic strain energy stored in the folded beams of the structure. Deployment of the dish structure from its folded configuration may be aided by auxiliary deployment means, such as leaf springs secured to the inner ends of the beams, an inflatable ring secured about the rim of the dish, guy wires extending between the rim and a telescopic actuator at the center of the dish, and/or a separable thin film cover defining with the dish an inflatable chamber.

Claims

1. A lightweight collapsible dish structure adapted to be folded for storage and deployed for use, comprising:

a generally dish-shaped member constructed of a plastic film such as Mylar or Kapton which is preformed to said normal dish shape;

a number of individual elastic beams of tubular cross section extending radially of and secured to said dish member and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said beams being preformed to normally assume a configuration wherein said dish member conforms to its normal dish shape;

said dish structure being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said dish structure when reLeased;

an inflatable ring extending about and secured to the rim of said dish structure; and

said ring being adapted to be deflated when said dish structure is folded to its stowage configuration and to be inflated during deployment of said dish structure for aiding such deployment, stretching said dish structure radially and reinforcing said dish structure against beam bending.

2. A lightweight collapsible dish structure adapted to be folded for storage and deployed for use, comprising:

a generally dish-shaped member constructed of a plastic film such as Mylar or Kapton which is preformed to said normal dish shape;

a number of individual elastic beams of tubular cross section extending radially of and secured to said dish member and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said beams being preformed to normally assume a configuration wherein said dish member conforms to its normal dish shape;

said dish structure being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said dish structure when released;

a rigid hub secured to the center of said dish structure; and

leaf springs secured to said hub and the inner ends of said beams for aiding deployment of said dish structure.

3. A dish structure according to claim 2 wherein:

said leaf springs extend radially out from said hub into the inner ends of said beams.

4. A lightweight collapsible dish structure adapted to be folded for storage and deployed for use, comprising:

a generally dish-shaped member constructed of a plastic film such as Mylar or Kapton which is preformed to said normal dish shape;

a number of individual elastic beams of tubular cross section extending radially of and secured to said dish member and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said beams being preformed to normally assume a configuration wherein said dish member conforms to its normal dish shape;

said dish structure being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said dish structure when released;

a front plastic film extending across the front side of and secured to the rim of said dish structure; and

said front film and dish structure defining therebetween an intervening hermetic chamber adapted to be pressurized for aiding deployment of said dish structure.

5. A dish structure according to claim 4 including:

means for separating said front film said dish structure.

6. A dish structure according to claim 5 wherein:

said separating means comprises a hot wire secured to and extending parametrically about said front film adjacent the rim of said dish structure and adapted to be heated by an electrical current for severing said front film said dish structure.

7. A lightweight collapsible dish structure adapted to be folded for storage and deployed for use, comprising:

a generally dish-shaped member constructed of a plastic film such as Mylar or Kapton which is preformed to said normal dish shape;

a number of individual elastic beams of tubular cross section extending radially of and secured to said dish member and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said beams being preformed to normally assume a configuration wherein said dish member conforms to its normal dish shape;

said dish structure being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said dish structure when released;

a rigid hub secured to the center of said dish structure;

a bag secured to said hub for containing said dish structure in its folded configuration, said bag having a mouth remote from said hub through which said dish structure Is adapted to deploy; and

means for releasably closing said mouth.

8. A lightweight collapsible parabolic reflector for a radiofrequency antenna adapted to be folded for stowage and deployed for use comprising:

a parabolic reflector dish constructed of a lightweight sheet-thin film having a front reflecting surface;

a number of individual elastic beams of tubular cross section extending radially of and secured to the back side of said parabolic dish and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said dish and beams being preformed to normally assume an unstressed configuration wherein said reflector conforms to its normal parabolic configuration;

said reflector being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said reflector to its normal parabolic configuration when released;

a rigid mounting hub secured to the center of said dish;

a telescoping actuator mounted on the front end of said actuator; and

said actuator being adapted to be retracted to a position wherein said element is situated adjacent said hub to facilitate folding of said dish to its stowage configuration, and said actuator being adapted to be extended to a position wherein said element is situated adjacent the focal point of said dish when said dish conforms to its normal parabolic configuration.

9. A parabolic reflector according to claim 8 including:

guy wires extending between the rim of said parabolic dish and the front end of said telescoping actuator.

10. A lightweight collapsible parabolic reflector adapted to be folded for stowage and deployed for use comprising:

a parabolic dish constructed of a lightweight sheet-thin film having a front reflecting surface;

a number of individual elastic beams of tubular cross section extending radially of and secured to the back side of said parabolic dish and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said dish and beams being preformed to normally assume an unstressed configuration wherein said reflector conforms to its normal parabolic configuration;

said reflector being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said reflector to its normal parabolic configuration when released; and

an inflatable ring extending about and secured to the rim of said parabolic dish.

11. A lightweight collapsible parabolic reflector adapted to be folded for stowage and deployed for use, comprising:

a parabolic dish constructed of a lightweight sheet-thin film having a front reflecting surface;

a number of individual elastic beams of tubular cross section extending radially of and secured to the back side of said parabolic dish and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said dish and beams being preformed to normally assume an unstressed configuration wherein said reflector conforms to its normal parabolic configuration;

said reflector being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said reflector to its normal parabolic configuration when released;

a rigid hub secured to the center of said dish; and

leaf springs secured to said hub and extending outwardly from said hub into the inner ends of said beams.

12. A lightweight collapsible parabolic reflector adapted to be folded for stowage and deployed for use, comprising:

a parabolic dish constructed of a lightweight sheet-thin film having a front reflecting surface;

a number of individual elastic beams of tubular cross section extending radially of and secured to the back side of said parabolic dish and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said dish and beams beIng preformed to normally assume an unstressed configuration wherein said reflector conforms to its normal parabolic configuration;

said reflector being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said reflector to its normal parabolic configuration when released;

a front film extending across the front side of and secured to the rim of said parabolic dish; and

said front film and parabolic dish defining an intervening hermetic chamber adapted to be pressurized during deployment of said dish.

13. A lightweight collapsible parabolic reflector adapted to be folded for stowage and deployed for use, comprising:

a parabolic dish constructed of a lightweight sheet-thin film having a front reflecting surface;

a number of individual elastic beams of tubular cross section extending radially of and secured to the back side of said parabolic dish and constructed of a sheet-thin plastic film such as Mylar or Kapton;

said dish and beams being preformed to normally assume an unstressed configuration wherein said reflector conforms to its normal parabolic configuration;

said reflector being adapted to be gathered and folded to a compact stowage configuration wherein elastic strain energy is stored within said beams for effecting deployment of said reflector to its normal parabolic configuration when released;

a rigid hub secured to the center of said dish;

a bag secured to said hub at the rear side of said dish for containing said parabolic reflector in its folded configuration, said bag having a mouth remote from said hub through which said parabolic reflector is adapted to deploy; and

means for closing said mouth.