close

Вход

Забыли?

вход по аккаунту

?

код для вставки
Nov. 5, 1946.
2,410,424
c. H. ‘ BROWN
OBSTACLE DETECTION - SYSTEM
Filed Aug. 18, 1942
2 Sheets-Sheet 1
13m
mukZDOU
NW
‘N
g..
A
Mango
CY .1
mmum.
.n
BROWN
R0.NR
W
w. .
Nov. 5, 1946.
c. H. BROWN
2,410,424
_
OBSTACLE DETECTION’ SYSTEM
Filed Aug. 18, 1942
'
-
2 Sheets-Sheet 2
POWER SUPLY
k
.9
MOT—-R\
I-CL-U—TCH-l
2
.
2.
Fig.
"g
V
s
.
+
|||--|||n'
s
'INVENTOR
,CHARL 3
BY ) "4%
. .
.BROWN
M'V'W
ATTORNEY
Patented Nov. 5, 1946
2,410,424
UNITED STATES PATENT ‘OFFICE
2,410,424
I OBSTACLE DETECTION SYSTEM
Charles H. Brown, Baldwin, N. Y., assignor to
Radio Corporation of America, a corporation of
Delaware
Application August 18, 1942, Serial N3. 455,207
25 Claims. , (Cl. 250—11)
1
This invention relates to improvements in 0b
stacle detection systems.
In obstacle detection systems, sometimes known
as radio locators, it has been proposed to detect
and observe distant and nearby objects by trans
mitting radio wave pulses as a result of which the
2
for the object to be detected, and when the ob
ject is detected to stop the hunting of the an
tenna approximately near the point at which the
object is detected and to cause an alarm.
A further object is to provide a circuit arrange
ment for a radio locating system by means of
which a pattern of signals corresponding to wave
objects are detected and observed by re?ected
pulses returning to the receiver at the same lo
pulses re?ected by known stationary objects in
cation as, or close to the transmitter. Often, the
,a field being scannedcan be compared with pat~
object detecting system employs directive an 10 terns obtained during succeeding cycles of scan
tennas utilizing parabolic re?ectors and other ex
ning, as a result of which only new signals which
pedients, for both transmitter and receiver by
were not present in a preceding pattern are caused
means of which the indications are con?ned to
objects lying within a narrow range of angles.
to operate an alarm.
A still further object is to enable the quick and
The antennas are sometimes given a continuous 15 e?icient detection of a moving object amid a plu
motion to scan a certain ?eld or range of solid
rality of stationary objects in a search area.
angles somewhat after the fashion of scanning a
Other objects will appear in the following de
television image, and ‘these antennas are linked
scription, which is accompanied by drawings
to a potentiometer which controls the voltage on
wherein Figs. 1 and 2 illustrate schematically two
the horizontal deflection plates of a cathode ray 20 embodiments of the present invention. Fig. 1 is
oscilloscope. Instead of wobbling the antenna
primarily designed for use in ?elds to be scanned
system as a whole, including the re?ector, it has
where there are known stationary objects, such
been proposed to change the radiation pattern
as buildings from which pulses are reflected. Fig.
of the antennas, such as by locating the radiating
2 is for use in ?elds to be scanned where there are
element off-center or eccentrically, so to speak, 25 no known stationary objects or targets.
and spinning the radiating element in a circle
Referring to Fig. 1 in more detail, the inven
relative to the re?ector, or by spinning a deflect
tion is shown applied to any suitable known type
ing element oiT the focus of the re?ector.
of radio locating apparatus I00 equipped with a
In such systems, the pulses re?ected by distant
scanning directional antenna I. The radio 10
objects are observed on an oscilloscope. Where
cating apparatus forms no part of the invention
known stationary objects are located in a particu
per se, except in combination with the features
lar ?eld being scanned, the attendant must fa
described hereinafter._ As an illustration of one
miliarize himself with the pattern of the waves
form of radio locating apparatus known in the
re?ected by the known objects in order that he
art, such a locator may include a pulse type trans
may become instantly aware of any new indica 35
mitter
for radiating over directional antenna I
tions or markings on the oscilloscope.
extremely short pulses of ultra short Waves.
From experiences had in the television ?eld,
These pulses should be very short; compared to
it is known that constant attentionto images ap
the time intervals between them. The receiver of
pearing on an oscilloscope produces eye fatigue
and a loss of alertness on the part of the attend 40 the locator is arranged to be inoperative to re
ceive during the time the pulses are being trans
ant after a period of time. Hence, it will be ap
mitted, but responsive to‘ signals or re?ected
preciated that in the use of radio locators it is
pulses only when these are due to arrive. Thus,
possible for the operator to overlook the mark
ing on an oscilloscope representative of an ob
by suitably adjusting the time of response of the
ject to be detected, such as an enemy plane or 45 receiver between the times of radiation of the
ship.
One of the objects of the present invention is
to produce an alarm in using a radio locating sys
tem, in order to attract the attention of the op
erator, whenever a newly found object is detected 50
by the apparatus.
-
Another object of the invention is to provide a
circuit arrangement for radio locators by means
of which the receiving antenna continuously
outgoing pulses, it is possible to determine the
distance of the object being detected from the 10
cating apparatus. Directional antenna I may
comprise any suitable re?ector, such as a para
bolic or cylindrical re?ector having one or more
dipoles or radiating elements at or near its focus,
preferably a stationary re?ector and a rotatable
oiT-center radiating element. In one form of 10
(Eating apparatus, the same radiating element is
hunts or scans through a wide angle or pattern 55 used. bQth for transmitting and receiving, there
2,410,424
3
connected to an armature 35 of relay 3| having
oppositely disposed contacts 36 and 31 by means
of which the coil 8 can be connected either to the
grid of vacuum tube pentode ampli?er 40 or to
invention, that antenna I have a wide angle of
the B+ plate supply through resistor 33. Pen
radiation, or directivity pattern, and that the
todejll has the usual resistors and condensers for
directivity pattern be rotated or changed by ro~
class “A” operation. Its plate is coupled via con
tating the radiating element located off the focus
denser 28 to the grid of vacuum tube triode 2I.
of the re?ector in order to achieve scanning.
This triode 2! has its plate connected through
With such a preferred arrangement, the antenna
can be rotated at a speed of about sixty times a 10 connection 46 to the cathode of gas triode I2,
and the cathode of tube 2i is coupled through a
second. Movement of the antenna I, in order
suitable counter circuit 53 to the control grid of
to scan the ?eld, is effected by means of shaft
gas triode or “Thyratron” 26. Resistors 23 and
2 linked at one end to the radiating element and
22 are also used for the grid and cathode, respec
at the other end to a magnetic clutch fl. Means
are provided, not shown, whereby the attendant 15 tively, of vacuum tube 2|. Resistors 24 and 21
form a potential divider between the B+ lead and
can disengage the antenna from the automatic
groundto maintain a high negative grid bias on
driving means and thus control the movement of
gas triode 26 by elevating the cathode potential
the antenna as a whole, by hand.
,
above ground. The plate circuit of this tube con
Where it is desired to rotate the entire antenna
tains in series the actuating coil of relay 3| and
system by moving the re?ector, which is not a
a switch 30. In the absence of energizing cur
preferred method due to the inertia of the sys
rent through the winding of relay 3I, contact
tem, the scanning or sweep of the antenna over
pairs 32-43, 36-45, and 34—44 will be normally
a desired angle may follow a standard saw-tooth '
open, while contacts 35-31 will be closed. Con
variation in which the forward sweep is very
slow compared to the return sweep. This can be 25 tact 3.2 is connected to the magnetizing coil of
clutch 4 and serves to complete the circuit of this
done by suitable cam mechanism connected in
coil with a 3+ lead through a resistor 29. The
known manner~ to the antenna I and shaft 2.
closure of contacts 34, 44 causes the operation of
In this case, the speed of scanning may be once .
relay 20 which in turn closes its contacts to oper
a second. Magnetic clutch 4 is so arranged that
the motion of the antenna I may be suddenly 30 ate a lamp ‘l0 and a bell 59 to attract the atten
tion of the operator. If desired, only one of
stopped at any position in response to energizing
these alarm indicators may be employed.
current in the coil of the actuating magnet of the
being circuits for rendering the receiver inopera
tive during periods of radiation.
It is preferred, for the purposes of the present
clutch.
This clutch is driven from a motor 5
Counter circuit 50 includes a suitable charge
storing condenser and leak resistor element,
which also drives loop 6 of magnetic tape. The
relative speeds of rotation or scanning cycle of 35 whereby a positive pulse is passed on to the grid
of gas tube 26 to operate this gas tube only when
the antenna I and the tape 6 must be such that
the charge on the condenser has reached a crit
the loop of tape 6 makes one complete circuit
' while the antenna I scans through a complete cy
ical value which will be the case when a pin
recorder coil ‘I in a manner described later. Tri
magnitude, a reshaper or trigger circuit consist
rality of pulses flow through tube 2i from succes
cle of movement twice. The detected output
from the receiver of apparatus I00 is fed through 40 sive cycles of scanning in a de?nite time period.
The counter serves to prevent operation of the
leads ill and audio transformer 9 into any suit
alarm due to random noise signals.
able pulse shaper. For the purpose of the inven
The operation of the system of Fig. 1 will now
tion. and by way of example only, there has been
be described in greater detail: Switch 30, whose
shown a pulse reshaper consisting of gaseous
function is described later, is normally open (as
grid controlled triodes I2 and I5, sometimes
shown), and switch 5! closed. The radio receiver
known as “Thyratrons.” This pulse reshaper I2,
of the locator I will receive the pulses re?ected
I5 may be referred to as a trigger circuit which
from the objects to be detected as the directional
requires an initiating pulse to change the con
antenna I scans or sweeps the ?eld, Each pulse
dition of equilibrium for a duration depending
received will appear as a pulse of voltage in the
in part upon the constants of the circuit ele
output leads 41. These pulses are recorded on a
ments and upon the electrode voltages. The term
loop of magnetic tape 6 which is exactly two
“reshaper” has been employed here because the
sweep cycles in length, for example. Due to the
circuit I2, I5 converts the shape of an initiating
fact that the pulses from the receiver of the ap
pulse applied to the grid of the tube I2 into a
paratus I00 may vary somewhat in shape and
substantially rectangular pulse for use by the
ing of gas triodes I2 and I5 with associated ele
odes I2, I5 have plate resistors II and I4 and
ments is provided. Normally, tube I2 is non-con
cathode resistors I6 and I9. A magnetic record
ducting and tube I -5 is conducting. When a pulse
ing coil 1 is connected in series with the oath
from the receiver appears in leads 41, it passes
ode resistor I6 of triode I2. A switch 5| is pro
through transformer 9 and is applied to the grid
vided in the lead between the recorder coil 1 and
of tube I2, thus ?ring or initiating conduction in
resistor I6. Normally, tube I2 is non-conducting
and tube I5 is conducting. The ?ring of tube I2
tube I2, as a result of which current is set up for
operating the recorder coil ‘I. When tube l2
will change the foregoing conditions of current
conduction in these two tubes. The grid of gas 65 starts conducting, it changes the condition of
charge on the condenser I3. thus reducing the
triode I 2 receives the incoming pulses from trans
voltage on the plate of tube I 2 below the arc sus
former 9 through resistor ID. The grid of triode
I5 is connected to a source of negative bias 0
taining value, as a result of which tube I5 ceases
through a large resistor I8 which is shunted by
conduction momentarily.
The tubes I2 and I5
70 regain their original status after a time interval
depending upon the value of the condensers I3
nected between the anodes of the two gas triodes
and II. In this manner a comparatively square
and its value determines the duration of the re
pulse of current is obtained from the cathode of
shaped pulse.
tube I2 for energizing the recorder coil 1 for each
A magnetic pick-up coil 8 is located half way
a small condenser IT.
A condenser I3 is con
around the tape from the recording coil 1 and is 75 received pulse, irrespective of its character.
2,410,424
5
6
Thus, all pulses received on the receiver 2, irreg
successive charging pulses to pass on a pulse to
?re gas tube 26, This pulse of. .current in tube
2| which occurs only for a newly received pulse
(that is, a pulse re?ected from an unknown ob
spective of their shape and magnitude, are re
_ corded on the tape alike.
Since the magnetic tape 6 is synchronized with
the scanning sweep of the antenna |, a panorama Cl ject not previously identi?ed) will be passed on,
of the radio signals in the angle being swept is
under the conditions mentioned above, as a volt
set up or registered on the tape as soon as the
age sui?cient to trip or ?re gas triode 26. ' The
tape has made a few revolutions. Because each
?ring of gas triode 26 energizes the coil of relay
known stationary object has a given position in
3| which quickly closes contacts 32-43 and
the ?eld being swept, the re?ected pulses from 10 34-44. The closure of the former contacts
each stationary object will always appear in the
causes magnetic clutch 4 to arrest the motion of
same position on the panorama. As the receiver
the antenna I, thus leaving the antenna approxi
continues to hunt or scan the ?eld, each known
mately at the position at which ‘the new object
object will have a' representative magnetic pulse
has been found. The operation of relay 3| by.
virtue of the closure ofv contacts 34---“ also
causes the relay 20 to operate and produce a‘
visual alarm by virtue of the lighting of the lamp
on the tape and no new pulses from the known
objects will be recorded, since each incoming
pulse will be applied at a point where it was pre
viously registered. At this time, switch 30 should
be closed and switch 5| opened.
‘l0 and an audible alarm by virtue, of the opera
tion of the bell 59.
'
In order to compare the panoramic radio 20
The operation of relay 3| also opens contact.
record on the tape 6 with the constantly incom
3‘|-—35 and closes contacts 36-35 to apply di
ing wave pulses, a pick-up coil 8 and a compara
rect current to pick-up coil 8 for magnetic eras
tor device are used. Since the tape is two sweep
ing. While the registered signals on tape 6 are
cycles in length and recorder coil 7 and pick-up
being erased, the attendant can manually move
coil 8 are spaced one cycle apart, the pulses 25 directive antenna | to follow the newly found
picked up by coil 8 will be at the same phase as
object which may be a plane or a ship. The re
those coming from the receiver through reshaper
lay 3| remains energized until switch 30 is opened
or trigger circuit l2, l5. Triode 2| compares
manually at the will of the operator. The pan
these incoming pulses with those already record
orama of signals may then be set up again on
ed on the magnetic tape 6, ‘since the incoming
the magnetic tape by closing switch 5|, after
reshaped pulses from the cathode of gas triode
which switch 3|] can be reclosed to put the sys
|2 are applied to the plate of this triode 2|, while
tem in readiness for hunting another new object.
the recorded pulses (as picked-up by coil 8 and
Fig. 2 shows the'invention applied to a radio
ampli?ed by pentode 40) are applied to the grid
of triode 2|. The pulse from the receiver applied
to the plate of tube 2| must be of opposite polarity
to the pulse simultaneously applied to the grid
of tube 2| by the pick-up coil 8 through pentode
40. This condition can be'assured by properly
poling the terminal connections of the pick-up
coil 8. Since the pulse applied to the plate of
tube 2| is always positive, the pulse applied to
the grid of tube 2| should always be nega
locator for scanning a ?eld where there are no
known objects or targets from which re?ected
pulses may be expected to be received. Such an
arrangement, for example, can be used in sweep
ing the open sky or the wide open spaces of the
ocean. The elements of Fig. 2 which are sim
40
tive and of a value sumcient to prevent space
ilar to those of Fig. 1 have been given the same
reference numerals. Essentially, Fig. 2 differs
from Fig. 1 by omitting the comparator device
and the recording scheme for registering the pan
orama of echo signals re?ected from known ob
jects.
‘
_,
current flow through tube 2|. When a new signal
The system of Fig. 2 includes, in addition to
or pulse suddenly appears in the observed ?eld,
the locating apparatus, the clutch 4 and the
due, let us say, to a moving craft appearing in
motor 5, a grid-controlled Thyratron trigger cir
the area or ?eld being scanned, the plate of tri
cuit 52. Coupled to the anode of tube 52, there
ode 2| will receive a reshaped pulse for this new
signal but since it has not been registered previ 60 is provided a relay 53 which operates upon the
?ring of the trigger circuit. The operation of
ously on the magnetic tape, the grid of this com
parator tube 2| will receive no matching o'r coun
relay 53 will cause the actuation of an alarm
‘ B|J___which may be a lamp Or a hell or both. The
ter-balancing negative pulse on its grid. Since
' operation of relay 53 will also close an obvious
the plate and grid pulses of objects already rec
ognized are of opposite polarity and cancel each 55 circuit over lead 51 for actuating the energizing
magnet of the clutch 4 in order to stop the move
other, the application of a pulse to the plate only
ment of the antenna ‘|. Relay 53 will remain
of tube 2| caused by the appearance of a new re
operated once it has been energized, until such
_ ceived pulse re?ected from a newly found obiect,
will produce a pulse of plate current which ?ows
through the cathode resistor 22.
If the newly
time as an attendant opens the switch 58. The
output of the receiver is connected by way of
become charged to a critical value and pass on
leads 4‘! to a relay 54 forming part of a mechan
ically resonant system in the form of a movable
reed 55. This reed is capable of engaging con
a voltage pulse to ignite tube 26, If, however, the
newly received pulse is caused by static, the
tact 56 upon maximum vibration. The resonant
reed system is accurately tuned to the timing of
charge on the condenser in counter 50 will leak
01f and no voltage will be passed to change the
antenna rotation, so that a multiplicity of small
impulses in the output of the receiver will cause
relays 54 to build up the amplitude of motion of
the reed to a maximum at which time the reed
55 will engage contact 56 and ?re the Thyratron.
The number of impulses required to cause reed
55 to engage contact 56 will depend upon the
received pulse recurs over a de?nite period of
time, a condenser in the counter circuit 50 will
condition of gas tube 26. Thus, if the radiating
element of antenna | is spinning at the rate of“
sixty times per second, the counter may be ad
justed to require ?fteen or thirty charging suc
cessive pulses before passing on a pulse to tube
26. However, if the entire antenna system is be
ing rotated at a speed of once or twice a second,
then the counter may be adjusted to requiretwo
Q of the mechanically resonant system which is
preferably large. The purpose of the mechan
ically resonant system is to prevent a single static
2,410,424
7
crash or two from causing actuation of the alarm.
In the operation of Fig. 2, let us assume that
the antenna I has a speed of rotation of'sixty
times per second, which is a simple matter‘when
a spinning antenna element is employed to vary
,
8-
'
I
,
from the wave pulses re?ected by known objects
in the ?eld being scanned, and utilizing new wave
pulses received from newly found objects in the I
?eld being scanned for automatically stopping
the scanning.
.
6. The method of operating an obstacle detec
the directivity pattern. Pulses received by the
tion system which includes the steps ofscanning
radio locator will produce voltage pulses'in leads
a predetermined ?eld at a constant and relatively
4'! and relay 54, which if repeated a predeter—
slow rate, returning the system to its original
mined number oi‘ times insynchronous relation
will cause the application to the grid of tube 52 10 point of scanning at a fast rate immediately after
the scanning operation to commence re-scanning
of a positive potential from the reed 55 of a' value
of .the same ?eld, receiving signals from objects
' suf?cient to ?re the trigger. The operation of
in the ?eld being scanned, detecting signals in
the trigger circuit 52 will operate the relay 53. I
‘the ?eld which were not present during a pre-'
The operation of relay 53 will achieve two re
sults: (1) Cause an alarm either visual or audible, 15 determined number of previous scanning opera
or both, and (2) actuate the clutch 4 to stop
tions, and utilizing the detected new signals to
movement of the antenna l approximately _ at
the position at which the object to be detected
automatically stop the scanning of the system
approximately at the scanning position at which
has been found. The trigger circuit 52 will sus
the new signals were received.
tain ‘its arc and relay 53 will remain operated 20
7. In an obstacle detection system utilizing the
until switch 58 in the anode circuit of thetrigger
transmission of wave pulses, a receiver, a‘ direc
is opened.
'
tive antenna coupled to said receiver, means for
It should be understood thatthe reed and trig
' continually and repeatedly changing the direc
ger circuit of Fig. 2 is merely illustrative of any
tivity pattern of said antenna over an area to
suitable scheme which can be employed to achieve 25 be scanned, means responsive to the detected out
the results of the invention.v
put of said receiver for producing indications rep- '
'What is claimed is:
resenting the positions of the signal wave pulses
1. The method of detecting an obstacle by
received from objects within the area being
ultra short radio waves which comprises direc
scanned, and means responsive to other wave
tively radiating ultra short radio wave pulses 30 pulses received within said area which do not reg
which are short compared to the time intervals
ister with said indications for stopping the scan
between them, automatically scanning a ?eld
ning of the antenna and for creating an alarm.
uniformly at a very low audio frequency rate
8. In an obstacle detection system utilizing the
while radiating said pulses, receiving wave pulses
transmission of radio wave pulses, a receiver, a
re?ected from an obstacle in the scanning ?eld _
directive antenna for said receiver, means includ
at time intervals lying between the periods of
ing a motor and a magnetic clutch linked there
pulse radiation, utilizing the received pulses to
to for continually and repeatedly changing the
stop the scanning, and audibly indicating the re
directivity pattern of said antenna over an area
ception of said wave pulses.
to be scanned, said magnetic clutch controlling
2. The method of operating a radio receiving 40 the mechanical coupling between said motor and
system which includes the steps of repeatedly
said antenna, an electric tube circuit coupled to
scanning an area for signals to be received, uti
the output of said receiver, an electromagnetic
lizing the signals from an object in the ?eld be
relay in the output of said electric tube circuit,
ing scanned to automatically stop the scanning
normally open contacts on said relay, a connec
at approximately the point at which the signals‘ 45 tion from one of said contacts to the exciting coil
are ?rst received, and simultaneously creating an
of said clutch, whereby the reception of pulses
alarm to attract the attention of the operator.
by said receiver causes the operation of said elec
3. The method of detecting an obstacle by
tric tube and said relay, as a result of which said '
radio waves which comprises directively radiat
clutch is disengaged from said antenna and the
ing radio wave pulses, repeatedly scanning a ?eld 60 scanning of said system is stopped.
while radiating said pulses, receiving wave pulses
9. In an obstacle detection system, a receiver,
re?ected from objects in the ?eld being scanned
a directive antenna therefor, means including a
at time intervals lying between the periods of
motor for continually and repeatedly changing
pulse radiation, and utilizing only those new wave
the directivity pattern of said antenna over a pre
pulses received in the ?eld being scanned which 65 determined ?eld to be scanned, a magnetic clutch
were not present during a predetermined number
between said motor and said antenna and
of previous scanning operations to automatically
adapted to open the link between said motor and
stop the scanning.
said receiver, means responsive “to the detected
4. The method of detecting an obstacle by
output of said receiver including a trigger circuit
radio waves which comprises directively radiating 60 and a magnetic tape recorder coupled to said
radio wave pulses, repeatedly scanning a ?eld
trigger circuit for producing recordings repre
while radiating said pulses, receiving wave pulses
sentative of the signals received within said area,
re?ected from objects in the ?eld being scanned
an electron discharge device circuit so arranged
at time intervals lying between the periods of
as to be operative solely by a received signal
pulse radiation, recording said received pulses, 65 which does not register with the recordings on
and creating an alarm upon receiving new Wave
said tape, a relay coupled to said electron dis
pulses which were not present during a predeter
charge device circuit and operative solely upon
mined number of previous scanning operations.
the flow of space current through said device, a
5. The method of detecting an obstacle by
pair of contacts for said relay one of which is
radio waves which comprises directively radiat 70 connected to the energizing coil of said magnetic
ing radio wave pulses, repeatedly scanning a ?eld
clutch and the other of which is connected to a
while radiating said pulses, receiving wave pulses
source of potential, whereby operation of said
reflected from objects in the ?eld being scanned
electron discharge device circuit operates said re- ,
at time intervals lying between the periods of
lay and causes the energization of said clutch
pulse radiation, producing temporary indications 75 with a resultant ?xationlof the antenna.
2,410,424
o
10-
.
the transmission of radio wave pulses, a receiver,
a directive antenna for, said receiver, means in
cluding a motor and a magnetic clutch linked
10. In an obstacle detection system, a receiver,
a directive antenna therefor, means for con
tinually and repeatedly changing the directivity
pattern of said antenna over a predetermined
?eld to be scanned, means responsive to the de
tected output of said receiver for producing indi
thereto for continually and repeatedly changing
cations representing the positions of the signals
received within said ?eld, and means operative
solely in response to new signals received within
said' same ?eld which do not registerwith said 10
ling the mechanical coupling between said motor
indications for producing an indication of an
other kind.
,
11. In a radio receiving system having a direc
tive antenna, means for continually and repeat
edly changing the directivity pattern of said an
tenna over a predetermined area, means respon
the directivity pattern of said antenna over an
area to be scanned, said magnetic clutch control
and said antenna, an electric tube circuit, an
electromagnetic relay'in. the output of said re
ceiver including a coil and a resonant vibratory
element responsive to the excitation of said coil,
said vibratory element in its position of maximum
vibration being adapted to operate said electric
tube circuit, and means‘responsive to the opera
15 tion of said electric tube circuit for operating said
clutch.
I
'
I
sive to signals received within said area being
scanned for- producing indications representing
-18. In a radio locator system, an indicator cir
cuit, means for transmitting a radio wave to both
the positions of said signals, and means operative
stationary and moving wave reflecting objects,
solely in response to new signals received ‘within 20 means for receiving the waves re?ected from said
objects, the waves re?ected from the stationary
said same area which do not register with said
objects recurring at said receiving means in an
indications for producing an indication of an
unchanging phase relation, and means for sub
other kind and for stopping movement of the di
stantially cancelling out the received waves from
rective antenna.
12. In a radio receiving system, a rotatable
antenna, a motor having a drive shaft linked to
said antenna for continually and repeatedly
said stationary objects and for supplying only
the waves received from said moving objects to
said indicator circuit.
19. In a radio locator system, an indicator cir
cuit, means for transmitting a radio wave to both
changing the antenna directivity pattern over a
predetermined ?eld to be scanned, a magnetic
clutch between said shaft and said antenna, an 30 stationary and moving wave reflecting objects,‘
means for receiving the waves reflected from said
output circuit for said receiver, a trigger circuit
coupled to said output circuit for converting the
shape of a voltage pulse appearing therein to sub
stantially rectangular wave form, a magnetic
tape having a recorder coil in circuit with said
trigger circuit for operation from said rectan
gular wave form pulse, said magnetic tape having
such length and driven at such speed that it
travels one complete revolution for an integral
number of cycles of scanning of the antenna, a
pick-up coil for said magnetic tape positioned
at a predetermined location on said tape, a nor
objects, the waves reflected from the stationary
objects recurring at said receiving means in an
unchanging phase relation, and means including
a moving endless magnetic conductor for sub
stantially cancelling out the received waves from
said stationary objects and for supplying only
the waves received from said moving objects to
said indicator circuit.
20. In a system for receiving recurring pulses
40
of energy, a signal collector, a resonant vibrating
reed relay, means for changing the reception pat
tern of said collector at an audio frequency rate,
means for impressing the energy collected by said
signal collector upon said reed relay, and an in
dicator system coupled to a contact of said reed
relay and responsive to closure of the contacts of
mally inoperative alarm, and a comparator device
in circuit both with said trigger circuit and said
pick-up and responsive to a signal received by
said receiver which does not register with pre
vious recordings on said tape for rendering said
alarm operative and for energizing said magnetic
said relay.
clutch to disengage said motor drive shaft from
21. In a radio object detection system for re
said antenna.
50 ceiving recurring pulses of'radio frequency energy
13. A system in accordance with claim 10, in
which are short in time duration compared to the
cluding a counter circuit for said last means,
time intervals between them, a radio signal col
whereby only a predetermined number of new
lector, means for changing the reception pattern
signals within a de?nite time limit renders said
of said collector at a low audio frequency rate,
last means operative.
55 a resonant vibrating reed relay coupled to said
14. A system in accordance with claim 8, in
signal collector, said relay having contacts which
cluding a resonant reed for preventing random
are normally open in the absence of energization
noise signals from operating said relay.
of said relay, and an alarm circuit coupled to a
15. The method of detecting an obstacle by
contact
of said reed relay and responsive to the
radio waves which comprises directively radiat
ing radio wave pulses, scanning a ?eld while O; O closure of the contacts of said relay.
22. In a radio system for receiving recurring
radiating said pulses, receiving pulses re?ected
pulses
of radio frequency energy, a directive an
from an obstacle in the ?eld being scanned, and
tenna, means for changing the directivity pat
utilizing the received reflected pulses to produce
tern of said antenna at a low audio frequency
an alarm and automatically stop the scanning.
rate, a resonant relay coupled to said antenna,
16. In a radio receiving system having a scan
said relay having contacts and requiring a plu
ning device, means for controlling said device,
rality of pulses to be applied to its winding in
and an alarm, the method of operating said re
order to become fully operative to close said con
ceiving system which includes the steps of re
peatedly scanning an area for signals to be re 70 tacts, and an indicator circuit coupled to a con
tact of said relay and responsive to the closure
ceived, and abstracting energy from the received
of the contacts of said relay.
signals to actuate said means to stop the scanning
23. In a radio system for receiving recurring
and to simultaneously operate an alarm to at
pulses of radio frequency energy, a directive sig
tract the attention of the operator.
17. In an obstacle detection system utilizing 75 nal collector, means for changing the directivity
11
2,410,424
pattern of said collector at a low audio frequency
tact of said relay and responsive to the closure
' rate, a resonant reed relay coupled to said signal
'of the contacts of said relay.
collector, said relay having contacts and requir
25. In a radio system for receiving recurring
ing a plurality of pulses to be applied to its wind
pulses of radio frequency energy, which pulses
ing in order to become fully operative, said relay ea are short compared to the time intervals between
being responsive-.to a frequency related ,to the
them, a directive signal collector, means includ
frequency of the recurring pulses, and having
ing a motor for continually changing the direc
contacts which are‘ normally open in the ab
tivity pattern of said collector, a resonant relay
sence of energization of said relay, and an in
coupled to said signal collector, said relay hav
dicator circuit including an electron discharge 10 ing contacts and requiring a plurality-of pulses
device coupled to a contact of said device, said
to be applied to itswinding in order'to become
electron discharge device being responsive to the
fully operative, said relay being responsive to a
closure of the contacts of said relay.
frequency related to the frequency of the recur-'
24. In a radio communication system, an an
ring pulses and having contacts which are nor- .
tenna, means for changing the reception pat
mally open in the absence of 'energization of said
tern of said antenna at a low audio frequency
relay, and an indicator circuit including an elec
rate, a resonant relay coupled to said antenna,
said relay having contacts and requiring a plu
rality of pulses to be applied to its winding in
order to become fully operative to close said con 20
)tron discharge device coupled to a contact of
said device, said electron discharge device being
responsive to the closure of the contacts of said
relay.
tacts, and an. indicator circuit coupled to a con
‘ CHARLES H. BROWN.
Disclaimer
'2,4l0,424.—-Oharles H.’ Brown, Baldwin, N. Y. OBSTACL E
DETECTION SYSTEM.
Patent dated Nov. 5, 1946. Disclaimer ?led Jan.
6,
1950,
by the assignee, '
I Radio Corporation of America.
Hereb enters this disclaimer to claim 18 of said
?ic'ial Gazette February 7', 1950.]
patent,
Документ
Категория
Без категории
Просмотров
0
Размер файла
1 010 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа