Note: Descriptions are shown in the official language in which they were submitted.
SLY
This invention chelates to the at of microwave wave guide
switches, and more particularly concerns an improved motor driven
microwave switch having reduced size and weight, but providing
supecio~ performance and reliability than error microwave
wave guide switches.
Typical wave guide switches have solid circular rotors with
semi-circular internal passages for microwave transmission in 90
increments. This type of rotor construction contains the
following disadvantages:
1) The size of the rotor it inherently of larger
diameter, with a higher inertia which
requires a larger housing and a larger motor
to drive the rotor between positions. Move
electrical energy will be needed and the
speed of switching will be impacted. Weight
and size are obviously effected by this
larger rotor.
2) Typically, microwave energy is transmitted in
hollow, rectangular metal conductors known as
wave guides. Discontinuities in the walls
such as air gaps or seams interrupt the flow
of energy causing losses in energy and
undesirable leakage. In the conventional
solid circular rotor, microwave energy it
transmitted from the stationary housing
through a rectangular air gap into the rotor.
The energy exits the rotor through a second
rectangular air gap into the housing. Energy
losses and leakages occur within the air gaps.
According to the invention, a microwave wave guide switch is
provided with a greatly simplified rotor which permits a much
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PAT 9861-1
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smaller and lighter switch housing, having corner an side cutouts
to further reduce the weight of the switch. Furthermore, in the
invention a vertical wall within the rotor has been eliminated.
The energy is transmitted through the rotor which consists of
three sides only, and the fourth wide is provided by the
stationary housing chamber wall thereby eliminating the two
vertical gaps typical of eke conventional rotor. Losses and
leakages associated with these air gaps have been eliminated
improving the performance of the switch. The small rotor provides
a reduced path length also resulting in lets insertion losses.
Some prior art wave guide switches have had a rotor con6istinq
of only the rectangular plate, but since the plate must rotate
within the chamber, the air gaps at the top and bottom produce
discontinuities in the vertical wall, resulting in losses and
leakages of energy between passages.
This invention describes a wave guide switch which it suitable
for all miccowave6 bands and whose design will provide superior
transmisfiion properties over a limited band or the pull band ox
microwave fcequencie6 at a substantial savings in weight, size,
inherent heating, cost, drive-motor prime power. All of these
improved properties ace vital for such applications as satellites
where requirements or 50 or more motor driven wave guide switches
per satellite are common. When the switch operates to transmit
microwaves at right angles; microwave propagation within the
switch is between the rotor and the walls of a chamber in the
switch housing wherein the rotor rotates. In this version of the
microwave switch, the rotor assumes either of two positions, OWE
apart to act like a
PAT 9861-1
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: Doyle pole, double throw switch, or a single pole, dollble
. throw switch. In another version the rotor as~emke~ either
- . ox three potion to act as a triple throw
. It is therefore a principal object of the present
5 : invention to optimize the switching and transmission porks
mange of a microwave wavegui~ switch by means of a witch
construction having reduced ire and weight and thereby rev
squiring a smaller and lighter motor than prior art microwave
. wave guide switches.
It is still another object of the present invention
to provide a microwave switch of the type described wherein
microwave propagation within the switch it between the switch
rotor and the chamber walls in which the rotor rotates.
It is another object of the prevent invention to
provide a microwave wived switch of the type dockyard
having a lightweight small diameter rotor housed in a small
lightweight housing requiring a small drive motor.
It it yet another object of the pronto invention
to provide a microwave wave guide witch of the type described
which ha a lightweight rotor which will witch fatter, it
canter to fabricate and is more reliable.
These and other oh~ects and many of the attendant
, advantages of this invention wow be readily appreciated as
_ Jo Iota tame becomes better understood by reference Jo the follow-
in detailed description when considered in connection with the
accompanying drawings in which:
Fig 1 it a I de elevation Al view of a microwave
with motor assembly embodying the invention,
Fig 2 it an end elevation Al view taken along line
I ox Pig 1,
I
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-ire-; I I I it an end elevation Al view taken along line
3 3 ox Fig. 1,
¦ Fig 4 it a cross ~ctional view taken along line
¦ 4-4 of Fig. 1:
I Fix. 5 it longitudinal, central sectional view taken
: I along line 5-5 of ~ig7 3:
Fig 6 it a reduced perspective view of the rotor of
the assembly of Fig. 1-5:
¦ Fig 7 it a side ~levational view of the rotor,
¦ Fig 8 is a plan view of the rotorjt~ken lung line
: I ¦ ~8-8 ox Fig. 7:
. I Fig 9 it a wide elevation Al view similar to Fig. 1
l ox another microwave switch-motor amiably embodying anywhere
¦ version ox Thea invention:
1 ¦ Fig. 10 and 11 are cross sectional vow taken along
¦ lye 10-L0 and ~1-11 of Fig. 9:
Fig 12 it an end elevation Al view taken along line
12 I of Fig 9.
Fig 13 is a reduced perspective view of the switch
. 20 7.. ¦ -I lion of the rotor employed in the amiably of Fig. 9-12:
¦ Fig. 14 is a side elevation Al view of the rotor of
Fog 13: and
¦ Fig. 15 it a plan view of the rotor taken along the
¦ line 15 15 of Fig. 14
I ¦ Referring now to the drawings wherein like reverence
¦ characters designate like or corresponding pats throughout
¦ there it illustrated in Fugue 1-5 a microwave switch-mot~r
amiably generally de~ignatQd as reference numeral I and have
¦ it a housing 22 made of lightweight metal Suckle a aluminum
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.. ., ."~ f,: Swahili
. wish Howe amok or 25 of ho switch assembly 20. The
Hugo 22 has a generally rectangular end portion I which
. Continue a witch portion 27 of a rotor 28 of the witch as-
: symbol 20, as best shown it Figs. 6-8.
.; End portion 26 of the housing 22 has rectangular and
' ~oxn~r cutouts 30D and central corner cutouts it which reduce
the wright of the assembly. The housing portion 26 ha four
flat tides 34 each provided with a rectangular opening 38 aft
. fording a direct passage fox microwave energy betweeJI the
hollow interior of the housing 22 and one of your waveg~ides 40
.. .. . Sheehan in dotted liner in Fig. 1) attachable by Casey 42
engaged in strew holes 44 at corners of thy slat sides I ox
the housing portion 26. The hollow housing portion I it formed
, with a cylindrical inside chamber avowing a wall I at which
. two rectangular openings 38 terminate. A flat end wall 48 of
the housing portion 26 has a recessed circular portion I
which it formed with an arcuate 180 opening 50 communicating
with the chamber 46. Threaded hole 52 in the wall 48 see
Fog. 2) receive screws for mounting the assembly 20 on a suit-
.- 20 able support 54 indicated by dotted lines in Fig. I A eon-
trial opening 56 in the recessed wall portion 49 receives a
cylindrical beaning 58 which journals a tub shaft 60 at the
outer end of the rotor 28.
The witch portion 27 of the rotor I has a pair of
US axially spaced cylindrical end plats 62, 64 fig. 7 & 8).
Between the end plates 62, 64 and integral therewith is a flat
central bloc 66, wow ha opposite flat parallel sides or
wall 680 The thlckn~s~ of the block 66 it equal to the circus-
. I frontal spacing of the openings 38 at the chamk~r 46 to insure
1 that wall ox passages for microwaves between selected pair of
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the openings 38 via the chamber 46 register with the sides of the
openings 38. All the openings 38 are of equal length and width.
The length of each wall 68 equals the length of each of the
openings 38. The width of each wall 68 is equal to the diameter
of each end plate 62, 64 which is precisely fitted to rotate
inside the chamber walls 47. The diameter of the chamber 46 is
thus substantially equal to that of the circular end plates 62,
64, and of the width of the walls 68 of the block 66. The
cylindrical end plates 61, 64 and the block 66 provide continuity
by eliminating gaps to reduce louses and prevent leakage of
microwave energy beyond the end plates in the chamber 46 axially
of the rotor 28 and the housing 22. The integral joining of the
ends of the block 66 with the plates 62, 64, reduces losses and
prevents leakage of microwave energy between passages in the
chamber 46 separated by the block 66. Outer wall 74 of the block
66 as shown in Fig. 4 are convex to fit flush with the concave
side walls of the chamber 46. Grooves 76 in opiate side of the
block 66 serve for fine tuning ox the micro switch assembly 58 to
past a prescribed broad band of microwave frequencies. The
reduction of gap losses and prevention of microwave leakage by the
plates 62, 64, and the block 66 insures that faithful propagation
of microwave frequencies through the rotor will be maintained.
End plate 64 it formed with an axial projection 80 extending 90
circumferential and rotatable disposed in the semi-circular
opening 50. Ends 82 of opening 50 in the recessed end wall
portion 49 of the housing 22 serve a abutments or stop for the
projection I to limit rotation of the rotor 28 to 90 in both
clockwise and counterclockwise directions as viewed in Fig. 2.
PAT 9861-1
So
A sector motor Z5 may be employed to turn the rotor 28. This
motor may be of conventional type such as described in US. Patent
No. 3,970,980 attached by screws 101 to the cylindrical end
portion 24 of the housing 22 is a circular plate 102 provided with
an opening 104 in which is fitted an insulated plug 106. Circuit
terminals 108 are fitted in the plug 106 wires 110 indicated by
dotted lines in Fig. 5 are connectable to the terminals 108 from
an external circuit which applies power to operate the motor 25.
Wire 112 inside the housing portion 24 are connected between the
terminals 108 and a stationary armature 114 of the motor 25. The
armature 11~ has inside and outside axial stationary shafts 116,
117. The inside shaft 116 extends through an opening in end wall
121 of a cup shaped motor housing 122 and contacts a belaboring
124 engaged in a souses in axial extension aye ox the plate 62.
The motor housing 122 it attached to the switch portion of the
rotor 28 by screw 126 engaged in holes in the plate or wall
extension aye. A ball bearing assembly 130 is disposed between
the motor housing wall 122 and the plate 62. The outer bearing
race 132 is held stationary at the inside wall of the chamber
46. The inner race is force fitted to the plate extension aye
and rotate with the rotor 28. The outer mounting shaft 117 of
the armature 114 is secured in a bore 134 by set screw 137. The
bore 134 is formed in axial projection 136 of the stationary end
plate 102 which is secured by screw 101 to an annular flange lg2
at the outer end of the cylindrical portion 24 of the housing 22.
Secured inside the cylindrical, cue shaped motor housing 122 are
arcuate permanent magnets I which rotate with the rotor 28
around the stationary armature 114.
The assembly 20 operates as a double pole switch in the
following manner. When the motor 25 it energized by current
PAT 9861~1
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of one polarity the rotor 28 Wright in one direction, for
example, clockwise, to the position shown in Fig. 4. Here the
arcuate rotor projection 80 will abut and rotation will be stopped
by the right end 82 of the 180 arcuate opening 50 in the wall 48;
see Fig. 2. There will now be two passages P and P' through the
microwave switch, between the switch portion 27 of the rotor 28
and the chamber wall 47 as indicated in Fig. 4. Passage P extends
between the upper opening aye, the chamber wall 47 and the side
opening 38b. Passage P' extends between the bottom opening 38C
and the side opening 38d. If the direction of current flow is
reversed in the armature 114, the rotor 28 will turn
counterclockwise as indicated by arrow in Fig. 4. This will
reverse the passages so that microwave energy passes through one
passage between the upper opening aye and the side opening 38d via
the chamber wall 47, and through another passage between the
bottom opening 38c and the side opening 38b via the chamber wall
47.
A triple position microwave switch motor assembly AYE is shown
in Figs. 9-12. The assembly AYE is similar to the assembly 20 of
Figs. 1-8 and corresponding parts are identically numbered.
A rotor aye shown in Figs. 10, 13, 14 and 15 has a pair of
thin, narrow, flat, parallel plate portions aye. Inner adjacent
sides 158 are spaced apart a distance equal to the width of each
rectangular opening in the chamber 46. Outer tides of the plate
portions aye are spaced apart a distance equal to the
circumferential spacing of the opening 38~ in the chamber I
By this arrangement, it is insured that walls of all passages
through the chamber I register with sides ox the openings 38 in
the chamber 46 in the two extreme and central positions of the
color in the housing. 90 axial, arcuats projection aye of a
circular end wall aye moves in an arcuate 180 opening aye in an
end wall aye of a housing aye.
PAT 9861-1
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When the rotor Zoo is turned clockwise OWE to the right from
the central the position shown in Figs. 10 and 12, the color aye
will have a position similar to that shown in Fig. 4. Then the
microwaves may flow in one passage between the openings aye' and
38b', and may flow in another passage between the openings 38c'
and 38d~. When the rotor aye is turned counterclockwise 45 to
the left from the central position shown in Fig. 10, the Roy aye
will have a position rotated 90 from that shown in Fig. 4. Then
microwaves may pass in one passage between the openings aye' and
dunned may pass in another passage between the openings 38c' and
38b'. The sector motor in housing 12Z will reverse the position
of the rotor in response to the polarity of current applied to the
motor armature 114 as described above in connection with the
assembly 20.
The structure of the housing aye is slightly modified from
that of the housing 22 in the assembly 20. Here an end wall aye
of a housing portion aye it seduced in mass by removing material
between corners leaving four corner ear 166 which register with
ears 168 provided on an end plate aye that carries the motor
armature 114 as shown in Fig. 5. Screws 180 engages a shaft aye
of the armature 114, see Fig. 9.
The switch potion aye of the housing aye is modified by
removal of material at the corners of the housing aye to define
four ears 170 which have holes aye to receive screws 172 for
mounting the assembly on a support.
It will be clear from the above that assembly aye serves as a
three position switch. There is a straight passage between the
openings aye' and 38c' when the rotor is in the central position,
shown in Fig. 10. When the rotor is turned ~5 in either
direction the passages P and Pi in Fig. 4. The rotor turns a
maximum of 90.
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PAT 9861-1
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Longitudinal slots aye are also formed at ends of the wall
edges and ace used for tuning the switch, and match-in impedances
to connecting wave guides. They also reduce coupling between paths
or passages through the switch.
My aforedescribed new and novel cotoc design is smaller in
diameter, lighter in weight and a consequently enclosed in a
smaller housing and is driven by a smaller drive motor which
Lucas less power then prior art wave guide switches. Moreover,
my new rotor is easier to fabricate (straight lines) and is more
reliable and can handle microwave power energy more efficiently
since self heating effects due to insertion loss are reduced.
That is the thermal expansion of my rotor, being smaller in
diameter is less than one of a larger diameter: and therefore less
prone to expand to where it seizes in the housing chamber. The
rotor construction insures that these will be no gap losses ox
undesired leakage of microwave energy out of the housing chamber
axially beyond the cylindrical end plates, and no leakage of
microwave enecqy between passages in the chamber separated by the
block integral with the end plates.
It should be understood that the foregoing relates to only a
limited number of pcefecred embodiments of the invention which
have been by way of example only, and that it is intended to cover
all changes and modifications of the examples of the invention
herein chosen for the purpose of the disclosure which do not
constitute departures from the spirit and score of the invention.
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PAT 9~61-1
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