VARIABLE CONTOUR REFLECTOR WITH COOLING SYSTEM
United States Patent 3644020
A circular reflector or mirror is mounted in a housing for rotation about a hollow shaft fixed to its center. A drive mechanism is provided to drive the reflector at various speeds. The reflector is provided with channels therein from its center to its outer periphery through which a coolant can flow from said hollow shaft to cool the reflector. A manifold is located around the periphery of the reflector to receive any coolant which passes therefrom. The coolant passes from the manifold and is recirculated through a cooler by a pumping means and directed back into the hollow shaft. Weights are located on the outer periphery of the reflector, offset from the center plane of the reflector, to provide a force when the reflector is rotated to vary its contour. The outer periphery of the reflector is connected to the manifold by sealing means to minimize loss of coolant at this point. The channels of the reflector can provide some pumping action if necessary.
Application Number:
05/017103
Publication Date:
02/22/1972
Assignee:
United Aircraft Corporation (East Hartford, CT)
Other Classes:
343/915, 352/202, 362/345
International Classes:
G02B26/08; G02B5/10; F21V29/00
Field of Search:
350/295,293,296,310,62,63,3,289 343/915 240/47,9A 352/202
Primary Examiner:
Schonberg, David
Assistant Examiner:
Leonard, John W.
Claims:
I claim
1. A beam-reflecting device having in combination, a circular mirror, said mirror having a shaft extending from one side thereof and being mounted for rotation about its center on said shaft, said mirror having weight means positioned evenly around its periphery on one side thereof, and means for rotating said mirror whereby said weight means act to vary the contour of the mirror.
2. A combination as set forth in claim 1 wherein cooling means are provided for said mirror.
3. A combination as set forth in claim 1 wherein said means for rotating said mirror includes a motor, said motor being drivingly connected to said shaft.
4. A combination as set forth in claim 2 wherein said cooling means includes passages in said mirror for flowing a coolant therethrough.
5. A combination as set forth in claim 4 wherein said shaft has a passageway therein, said passageway being connected to said passages, means for delivering a coolant through said passageway to said passages.
6. A combination as set forth in claim 4 wherein said passages extend radially and act to move the coolant from the center of the mirror to its periphery.
7. A combination as set forth in claim 6 wherein said passages intersect the periphery of the mirror and form holes therearound.
8. A combination as set forth in claim 7 wherein a collector is connected to the holes around the periphery of the mirror to collect the fluid flowing therefrom.
9. A combination as set forth in claim 8 wherein conduit means connect said collector to said passages in said mirror.
10. A combination as set forth in claim 9 wherein said shaft has a passageway therethrough, said passageway forming part of the conduit means.
11. A combination as set forth in claim 9 wherein said conduit means includes a cooler for controlling the temperature of the coolant.
Description:
BACKGROUND OF THE INVENTION
This invention relates to a beam reflecting device having means for varying the contour of the reflecting surface during operation. U.S. Pat. No. 2,952,189 shows one example of a reflector having an adjustable focal length. U.S. application Ser. No. 733,221, now U.S. Pat. No. 3,514,776, shows other examples of reflectors having variable reflecting surfaces.
SUMMARY OF THE INVENTION
The primary objective of the invention is to provide an improved beam reflecting device where the focal point of the reflecting surface is varied by rotation.
In accordance with the present invention, the reflector rotation provides for even heating of the surface to minimize surface warpage from nonuniform surface heat input or hot spots. The uniform temperature in the circumferential direction will provide symmetrical thermal distortions.
The reflector can also be cooled by a heat exchanger having grooves under the reflecting surface. With the cooling grooves extending radially outwardly from the center of the mirror the passages can be arranged as a centrifugal pump impeller to pump coolant flow. An auxiliary pump can also be provided in this system for a greater range of coolant flow or reflector shape and r.p.m. requirements.
The weights are spaced sufficiently close and evenly spaced to provide smooth contouring.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view partially in section of the invention.
FIG. 2 is a view of the reflecting surface of the device with a portion thereof broken away.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 the beam reflecting device 1 is shown comprised of four main parts; (1) the reflector or mirror 3, (2) the drive means 5, (3) the cooling system 7, and (4) the mounting means 9.
The reflector or mirror 3 comprises a thin circular mirror member 11, on one side, having, a reflecting surface 12, which has its opposite side fixed to a grooved side of a circular supporting member 13. Supporting member 13 has its rearward surface flat while its forward surface is grooved by ribs 15 forming channels 17, as shown in FIG. 2. The assembled mirror is adapted to be cooled by a coolant flowing through said channels. A plurality of balance weights 18 are located around the outer periphery of the rearward flat surface of the supporting member 13 for a purpose to be hereinafter described.
A hollow shaft 19 extends rearwardly from the rearward flat surface of the supporting member 13 and a flange 21 thereon is fixed to said member by bolts or any other means desired. This shaft extends coaxially from the circular supporting member. Hollow shaft 19 is rotatably mounted in housing 23 of the mounting means 9. A ball bearing assembly 25 has its inner race fixed to the forward end of said hollow shaft and has its outer race fixed to the housing. This ball bearing assembly prevents axial movement of the shaft with respect to the housing. A roller bearing assembly 27 has its inner race fixed to the rearward end of the hollow shaft 19 and has its outer race fixed to the housing. The roller bearing permits axial movement to provide for thermal movement of the shaft with respect to the housing.
The middle of the housing 23 is enlarged to provide for a power transmission to be located therein. A bevel gear 30 is fixed to the hollow shaft 19 and it meshes with a bevel gear 32 which is fixedly mounted to a drive shaft 34. A driving device 36 including a case 38 having a motor inside with a shaft 34 extending therefrom is fixed to said housing. Mounting flanges 40 on the case 38 are fixed to brackets 42 on the housing 23. The drive shaft 34, extends through a hole in the housing. A speed control 44 controls the speed of the motor in the casing 38.
Radial arms 50 extend from the forward part of housing 23 and are connected to an annular supporting member 52 which has a purpose to be hereinafter described. Legs 54 extend from said annular member and fix this end of the device. Legs 56 extend from the rearward part of the housing 23 and fix that end.
It can be seen that as the motor is energized by the speed control it will rotate bevel gear 32 which will in turn rotate gear 30 and the hollow shaft 19. Rotation of shaft 19 rotates the mirror 3. In view of the location of the balance weights 18, as the speed of the reflector or mirror increases the supporting member 13 and mirror member 11 will begin to move forwardly at the outer edge forming a concave reflecting surface. It is to be remembered that these movements need not be very large. U.S. Pat. No. 3,229,578 refers to reflectors made of flexible material.
An annular collector 60 is mounted on the annular member 52 and has an annular inlet 62 positioned to receive any coolant flow which may pass through the channels 17 from the hollow shaft. Annular seal means 66 and 68 prevents leakage at the periphery of the mirror 3. The seal means 66 and 68 each are shown comprising a labyrinth type and are located on the front and rear side of the mirror 3. Other types of seal means desired can be used.
Annular collector 60 has an outlet 70 which directs its flow into a conduit 72 which has its other end connected to the inlet of a pump 74. The outlet of pump 74 is connected to the free end of hollow shaft 19 by conduit 76. The hollow shaft 19 is rotatably mounted in the conduit 76 and a seal means is located between said members. A cooler 78 is positioned in the line 72. While the ribs 15 on the supporting member 13 are formed to provide a pumping action for the coolant, a pump 74 is provided for a greater range in operating conditions.