Collapsing paraboloid dish and method

Information

  • Patent Grant
  • 6625288
  • Patent Number
    6,625,288
  • Date Filed
    Friday, March 31, 2000
    24 years ago
  • Date Issued
    Tuesday, September 23, 2003
    21 years ago
Abstract
A paraboloid receiving dish having a base, a receiver coupled to the base, and a plurality of petals pivotably connected to the base. The petals are moveable between an open position and a closed position with each of the positions forming a reflector having a parabolic shape.
Description




BACKGROUND OF THE INVENTION




The present invention concerns receiving dishes, particularly paraboloid dishes used to receive sound and radio signals, such as microphones and RF antennae.




Receiving dishes are generally single piece paraboloid shaped dishes. They are generally shallow in depth to allow for easier manufacture and shipping. However, shallow dishes are susceptible to stray signals from sources positioned to the sides of the receiving dish. Alternatively, deeper one piece dishes reduce the stray signal problem but the cost to manufacture, package, and ship a one piece deep parabolic dish is unwieldy and expensive.




Present dishes also include folding umbrella type receiving dishes. These are generally used in low-gravity space applications. These dishes consist of a skeleton with a flexible cloth-like covering. These dishes are functional only when fully open, requiring set up before the dish is operational.




There are at least two problems with these receiving dishes. First, a deep dish with good selectivity with low stray signal interference has a high cost of manufacture and shipping. Second, umbrella-type folding dishes only operate when in the fully open position. Third, these present dishes are not adjustable in diameter or depth, nor is the gain of the receiver adjustable by adjusting the diameter and depth of the receiver. Thus, there is a need for a collapsible parabolic dish that is deeper in depth that allows easier manufacture and shipping. There is also a need for a collapsible parabolic dish that is operable in both the open and closed position and has an adjustable diameter and depth and an adjustable gain.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of one embodiment of a collapsible paraboloid dish in an open position.





FIG. 2

is a cross sectional side view of one embodiment of a collapsible paraboloid dish in an open position.





FIG. 3

is a perspective view of one embodiment of a collapsible paraboloid dish in a closed position.





FIG. 4

is a cross sectional side view of one embodiment of a collapsible paraboloid dish in a closed position.





FIG. 5

is a side front view of one embodiment of a collapsible paraboloid dish in a fully open position.





FIG. 6

is a side front view of one embodiment of a collapsible paraboloid dish in a an first intermediate partially open position.





FIG. 7

is a side front view of one embodiment of a collapsible paraboloid dish in a second intermediate partially open position.





FIG. 8

is a side front view of one embodiment of a collapsible paraboloid dish in a fully closed position.





FIG. 9

is a partial front view of one embodiment of a collapsible paraboloid dish showing a single petal in an open position.





FIG. 10

is a partial front view of one embodiment of a collapsible paraboloid dish showing a single petal in a closed position.





FIG. 11

is a cross sectional view of one embodiment of a collapsible paraboloid dish showing a single petal in a open position.





FIG. 12

is a cross sectional view of one embodiment of a collapsible paraboloid dish showing a single petal in a closed position.











DETAILED DESCRIPTION




In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.




To address these needs, one exemplary embodiment of a receiving dish includes a base, a receiver coupled to the base, and a plurality of petals pivotably connected to the base. The petals are moveable between an open position and a closed position, each of the positions forming a reflector having a parabolic shape.




Advantageously, the receiving dish is a collapsible deep paraboloid dish that allows for easier manufacture and shipping. The collapsible parabolic dish is operable in both the open and closed position and has an adjustable diameter and depth and adjustment of the gain of the receiver.





FIG. 1

shows an exemplary receiving dish


10


, such as an acoustical receiving dish. Receiving dish


10


has a base


12


, a receiver


14


coupled to base


12


, and a plurality of petals


16


. Each petal


16


pivotably connects to base


12


and moves between an open position


18


and a closed position


20


(See FIG.


3


and FIG.


4


). Base


12


and plurality of petals


16


form a first reflector


22


in open position


18


. The receiver


14


is shown as a microphone, but alternatively receiver


14


is any receiver of energy focused by receiving dish


10


, such as sound or electrical energy. Receiver


14


is a boundary layer reflector microphone that concentrates the acoustic waves against a surface forming a high pressure boundary layer yielding a 3 dB increase in sensitivity. Receiver


10


connects to a cable


24


and a jack


26


for connection to another device (not shown). Cable


24


passes through handle


28


.





FIG. 2

shows a cut away side view of an exemplary receiving dish


10


. First reflector has an open focal depth


30


, a open depth


32


, and an open diameter


34


. Receiving dish


10


preferably has a high selectivity. High selectivity is obtained by placing receiver


14


at focal depth


30


deep within first reflector


22


. Open depth


32


is preferably equal to or greater than open focal depth


30


so that receiving dish


10


provides better selectivity. The shape of a parabolic receiving dish is commonly described using the ratio of focal depth to diameter. The ratio of focal depth to diameter is 0.25 for a parabola having a focal depth equal to the depth. Receiving dish


10


preferably has a ratio of open focal depth


30


to open diameter


34


equal to or greater than 0.25.





FIG. 3

shows an exemplary receiving dish


10


in a closed position


20


. Plurality of petals


16


are pivoted approximately 180 degrees from open position


18


to closed position


20


forming a second reflector


36


. In open position


18


each petal


16


extends outwardly from base


12


. In closed position


20


each of the petals


16


are positioned across base


12


. Each of the petals


16


are semi-rigid or slightly flexible so that they bend to fit the curve of base


12


as they are rotated from open position


18


to closed position


20


. The petals


16


are resilient so that as the petals


16


move from the closed position


20


to the open position


18


they return to their original shape.





FIG. 4

shows a side view of exemplary receiving dish


10


in the closed position forming second reflector


36


. Second reflector


36


has a closed focal depth


38


, a closed depth


40


and a closed diameter


42


. Second reflector


36


has a ratio of closed focal depth to closed diameter equal to or less than 0.25. Alternatively, the ratio may be greater than 0.25, depending on the needed selectivity in the closed position.




FIG.


5


through

FIG. 8

show an exemplary receiving dish in a range of positions from open position


18


in

FIG. 5

to closed position


20


in

FIG. 8

with

FIG. 6

showing a first intermediate position


42


and

FIG. 7

showing a second intermediate position


44


. The receiving dish


10


maintains a substantially parabolic shape and remains operational throughout the range of positions.




Each of

FIGS. 5-8

show an exemplary embodiment of receiving dish


10


having a base


12


, a receiver


14


, and a plurality of petals


16


. Each of the petals


16


are pivotably connected to the base


12


with a fastener


46


. (Base


12


and fastener


46


not shown in FIG.


8


). Fastener


46


is shown as a plastic pin with a flat head on the inside of receiving dish


10


. However, fastener


46


is alternatively any fastener allowing the petal


16


to pivot from open position


18


to the closed position


20


. Fastener


46


also provides a position stop


48


for an adjacent petal


50


. In open position


18


, adjacent petal


50


is stopped from pivoting past the open position


18


by the fastener


46


. Each of the petals


16


has a notch


52


that is positioned so that the petal


16


may pivot about 180 degrees from open position


18


to the closed position


20


. Notch


52


provides clearance for the receiver


14


to allow the petal


16


to rotate to closed position


20


. Each of the petals


16


overlap an adjacent petal


50


to provide a continuous reflector


54


through out the range of positions. Receiving dish


10


is shown with fifteen petals. More petals may be used with increased cost or as few petals as fourteen may be used before gaps begin to appear between the petals at intermediate positions


42


,


44


of receiving dish


10


.




FIG.


9


and

FIG. 10

show an exemplary petal


16


connected to base


12


.

FIG. 9

shows petal


16


in open position


18


and

FIG. 10

shows petal


16


in closed position


20


. Each petal


16


is comprised of plastic, such as polyethylene or polypropylene and is about 0.0030 to about 0.0040 inches thick, which is an approximate lower limit for thinness using injection molding. Alternatively, petal


16


is comprised of other higher cost materials such as stainless steel or film plastics which are thinner and have less memory allowing a deeper receiving dish with a lower focus depth to diameter ratio. Petal


16


has a short dimension


56


and a long dimension


58


. Long dimension


58


is from fastener


46


to the outside edge


60


of petal


16


and short dimension


56


transverses long dimension


58


running from a first side edge


62


to the a second side edge


64


. First side edge


62


rests against fastener


46


and position stop


48


when petal


16


is in open position


18


. Each petal


16


has notch


52


located along second side edge


64


of petal


16


about midway between the fastener


56


and outside edge


60


of petal


16


. Notch


52


is sized to receive receiver


14


when petal


16


is closed position


20


.





FIG. 11

shows a partial cross sectional view of an exemplary receiving dish


10


in open position


18


. The vertex


66


of receiving dish


10


is placed on the origin of the x-y axis so that a parabolic curve


68


is defined by the equation x


2


=4cy, where c is equal to the focal depth of parabolic curve


68


. Receiving dish


10


has a substantially parabolic shape with base


12


and petal


16


substantially following the parabolic curve


68


. The outside edge


60


of the petal is at a point substantially on the parabolic curve


68


where y=open depth


32


, x=open diameter


32


divided by 2, and c=open focal depth


30


.




The curvature


70


of base


12


uses a profile of a parabola that is about 20% narrower in diameter based upon the same depth. This achieves tensioning of the individual petals


16


with each other throughout their travel.




The first curvature


72


of petal


16


in the long dimension


58


approximates a sphere curvature of a diameter corresponding to open diameter


34


. This helps provide tension between the petals in the open position


18


.





FIG. 12

shows a partial cross section of an exemplary receiving dish


10


in closed position


20


. The vertex


66


of receiving dish


10


is placed on the origin of the x-y axis so that parabolic curve


68


is defined by the equation x


2


=4cy, where c is equal to focal depth of parabolic curve


68


. Receiving dish


10


has a substantially parabolic shape with base


12


and petal


16


substantially following the parabolic curve


68


. The outside edge


60


of the petal is at a point substantially on the parabolic curve


68


where y=closed depth


40


, x=closed diameter


42


divided by 2, and c=closed focal depth


38


.




Petal


16


flexes to a deflected curvature


74


to accommodate the different curvatures between open position


18


and closed position


20


.




Petal


16


also has a second curvature


76


in short dimension


56


that is a degenerate parabolic section. The second curvature


76


is degenerate in that second curvature


76


is reduced or flatter than a parabolic curve. The second curvature


76


achieves better tension of receiving dish


10


in open position


18


, and allows petals


16


to more easily lie on top of each other in closed position


20


.




In one embodiment, open diameter


34


is about 8 inches and closed diameter


42


is about 4.5 inches. Open diameter is about two times as large as closed diameter. Open depth


32


is about 3 inches and closed depth is about 1 inch. Open depth is about three times as large as closed depth


40


. Open focal depth


30


is about 1.25 inches, about the same as closed focal depth


38


. The ratio of focal distance to diameter in open position


18


is about 0.16 and the ratio of focal distance to diameter in closed position


20


is about 0.28.




Alternatively, the closed position


20


is adjusted to a larger closed diameter


42


resulting in a ratio of focal distance to diameter of 0.25 or greater.




The maximum change in depth and diameter occurs if in the closed position, the outside edge of the petal is at the outer perimeter


78


of the base


12


resulting in the open diameter about 2.5 times larger than the closed diameter and the open depth about 6 times larger than the closed depth.




The diameter and depth of the receiving dish


10


are adjustable throughout the range of positions between open position


18


and closed position


20


. Adjusting the diameter and depth of receiving dish


10


also adjusts the gain of receiving dish


10


so that the gain may be adjusted during operation by adjusting the depth and diameter.




An exemplary method of adjusting a receiving antennae includes providing a parabolic shaped antennae comprising a plurality of petals and adjusting the depth and diameter of the antennae by repositioning the plurality of the petals. One exemplary method further includes adjusting the gain of the antennae by repositioning the plurality of petals.




Another exemplary method further provides that each of the plurality of petals are pivotably connected to a base and moveable between an open position and a closed position. In the open position, the base and plurality of petals form a first reflector having a substantially parabolic shape. In the closed position the base and the plurality of petals form a second reflector having a substantially parabolic shape. Another exemplary method further provides operating the antennae in the open position, the closed position and throughout the range of positions between the open position and the closed position.




Advantageously, the collapsible deep paraboloid receiving dish allows for easier manufacture and shipping. The collapsible dish is operable in both the open and closed position and has an adjustable diameter and depth and an adjustable gain of the receiver.




It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.



Claims
  • 1. A receiving dish comprising:a base; a receiver coupled to the base; a plurality of petals, each of the plurality of petals pivotably connected to the base and moveable between an open position and a fully closed position; wherein in the open position the base and plurality of petals form a first reflector having a substantially parabolic shape; and wherein in the fully closed position the base and the plurality of petals form an operational second reflector having a substantially parabolic shape.
  • 2. The dish of claim 1 wherein the base and the plurality of petals form a substantially parabolic shape throughout a range of positions between the open position and the fully closed position.
  • 3. The dish of claim 1 wherein the base, receiver, and plurality of petals are operable in the open position, the fully closed position and throughout the range of positions between the open position and the fully closed position.
  • 4. The dish of claim 1 wherein the first reflector has a focal depth, a diameter, and a ratio of the focal depth to the diameter, wherein the ratio is less than about 0.25.
  • 5. The dish of claim 4 wherein the second reflector has a focal depth, a diameter, and a ratio of the focal depth to the diameter, wherein the ratio is less than about 0.25.
  • 6. The dish of claim 1 wherein the base has a curvature, a depth, and a diameter, wherein the curvature of the base is narrower than a curvature of each petal.
  • 7. The dish of claim 1 wherein the first reflector has a first diameter and the second reflector has a second diameter, wherein the first diameter is up to about 2.5 times larger than the second diameter.
  • 8. The dish of claim 1 wherein the first reflector has a depth and the second reflector has a depth, wherein the first depth is up to about 6 times the second depth.
  • 9. The dish of claim 1 wherein the first reflector has a first diameter and a first depth and the second reflector has a second diameter and a second depth, wherein the first diameter is up to about 2 times larger than the second diameter and the first depth is up to about 3 times larger than the second depth.
  • 10. The dish of claim 1 wherein the plurality of petals comprise at least 14 petals.
  • 11. The dish of claim 1 further comprising a plurality of fasteners, each of the fasteners pivotably connecting one of the plurality of petals to the base.
  • 12. The dish of claim 11 wherein each of the fasteners is positioned such that each fastener provides a stop for an adjacent petal.
  • 13. A receiving dish comprising:a base; a receiver coupled to the base for receiving signals; a plurality of petals, each of the plurality of petals being pivotably connected to the base and moveable between an open position and a fully closed position; wherein in the open position the base and plurality of petals form a first reflector having a substantially parabolic shape; wherein each of the petals overlaps an adjacent petal in the open position and wherein each of the petals overlaps the base in the fully closed position such that the base provides tension to the plurality of petals in the fully closed position and the receiving dish remains operational between the open position and the fully closed position.
  • 14. The dish of claim 13 wherein in the fully closed position the base and the plurality of petals form a second reflector having a substantially parabolic shape.
  • 15. The dish of claim 13 wherein each of the plurality of petals is comprised of plastic.
  • 16. The dish of claim 13 wherein each of the plurality of petals is comprised of a plastic from the group of polyethylene and polypropylene.
  • 17. The dish of claim 13 wherein the each of the plurality of petals have a thickness of about 0.0030 to about 0.0040 inch.
  • 18. The dish of claim 13 wherein each of the plurality of petals has a first curvature along a long dimension of each of the plurality of petals.
  • 19. The dish of claim 18 wherein the first curvature approximates a sphere curvature.
  • 20. The dish of claim 13 wherein each of the plurality of petals has a second curvature along a short dimension of each of the plurality of petals.
  • 21. The dish of claim 20 wherein the second curvature is less than the first curvature.
  • 22. The dish of claim 21 wherein the second curvature provides tension between each of the plurality of petals.
  • 23. The dish of claim 22 wherein the second curvature allows the petals to overlap each other in the fully closed position.
  • 24. The dish of claim 13 wherein each of the plurality petals overlaps two adjacent petals.
  • 25. The dish of claim 13 wherein each of the plurality of petals comprise a notch, the notch positioned along an edge of each of the plurality of petals to receive the receiver in the fully closed position.
  • 26. The method of adjusting a receiving antennae comprising:providing a parabolic shaped antennae comprising a plurality of petals; and adjusting the depth and diameter of the antennae by repositioning the plurality of petals while maintaining a substantially parabolic shape of the parabolic shaped antennae; wherein each of the plurality of petals are pivotably connected to a base and moveable between an open position and a fully closed position, wherein in the open position the base and plurality of petals form a first reflector having a substantially parabolic shape, and wherein in the fully closed position the base and the plurality of petals form a second reflector having a substantially parabolic shape; and operating the antennae in the open position, the fully closed position and throughout the range of positions between the open position and the fully closed position.
  • 27. The method of claim 26 further comprising adjusting the gain of the antennae by repositioning the plurality of petals.
  • 28. The method of claim 26 whereinoperating the antennae in the fully closed position includes engaging a notch positioned along an edge of each of the plurality of petals with a receiver.
  • 29. A receiving dish comprising:a base; a receiver coupled to the base; a plurality of petals, each of the plurality of petals pivotably connected to the base and moveable between an open position and a closed position; wherein in the open position the base and plurality of petals form a first reflector having a substantially parabolic shape; and wherein each of the plurality of petals comprise a notch, the notch positioned along an edge of each of the plurality of petals to receive the receiver in the closed position.
  • 30. The dish of claim 29 wherein the base and the plurality of petals form a substantially parabolic shape throughout a range of positions between the open position and the closed position.
  • 31. The dish of claim 29 wherein the base, receiver, and plurality of petals are operable in the open position, the closed position and throughout the range of positions between the open position and the closed position.
US Referenced Citations (6)
Number Name Date Kind
3176303 Holland Mar 1965 A
3699576 Hoyer Oct 1972 A
3715760 Palmer Feb 1973 A
3895188 Ingraham Jul 1975 A
4899167 Westphal Feb 1990 A
5198832 Higgins et al. Mar 1993 A