close

Вход

Забыли?

вход по аккаунту

?

код для вставки
Sept. 24, 1946.
H. 1.. H_ULL ET AL
I
AUTOMATiC POSITIONAL CONTROL OF OBJECTS
Filed Dec. 31, 1941
2,408,068
'
3 Sheets-Sheet 1_
I“ g.
l'lI
lNVENTORS,
DIRECTO
HARVARD L. HULL
gnlauhmw
Sept. 24, 1946.
2,408,068
H. L. HULL ET AL
AUTOMATIC POSITIONAL CONTROL OF OBJECTS
Filed Dec. 51, 1941
3 Sheets-Sheet 2
_
INVENTORS,
H.HUL_L, W.GORRILL, qnd
Y
.
Sept. 24, ‘1946.
' H. L. HULL ETAL
2,408,068
AUTOMATIC POSITIONAL CONTROL OF OBJECTS
Filed Dec. 31, 1941
I08
'
’
SSheets-Sheet 3 7
MANUAL
'
'AUTOMATiC
INVENTORS,
H. HULdL,
W. GORRILL,
on
W. FROST;
Patented Sept. 24,1946
orso STATES
2,408,068
AUTOMATIC POSITIONAL CONTRGL
OF OBJECTS
Harvard L. Hull, East Williston, William S.
Gorrill, Hempstead, and William F. Frost,
Williston Park, N. Y., assignors to Sperry Gyro
scope Company, Inc., Brooklyn, N. Y., a corpo
ration of New York
Application December 31, 1941, Serial No. 425,146
10 Claims.
(Cl. 60—53)
1
2
This invention relates to systems for control
ling the movement of bodies possessing substan
tial inertia, such as rotatably mounted guns and
the like, and it refers more particularly to a sys
tem for automatically positioning a gun in ac
cordance with angular data supplied from a re
the above character protection against overload
ing of the driving means, including means for
causing delayed or only partial response to sud
mote source such as a ?re-control director.
prevent overrunning without putting undue
A further object is to provide in a system of
denly changing data.
'
.
A further object is to provide limit stops which
In the past, guns and particularly anti-air
strain on the driving means.
craft guns, have been aimed manually in eleva
Still another object is to provide in an auto
tion and in train (azimuth) according to data 10 matic system of the above character suitable
exhibited by indicators at the gun, such as dials
switching means for conversion to manual oper
rotated by the receivers of self-synchronous
ation.
transmission systems over which the data arrived
In the drawings,
from a remote director. The men aiming the
Fig. 1 is a schematic diagram of a gun-posi»
gun in accordance with received data, in such 15 tioning system embodying one form of the in
systems, are situated alongside of the gun and
vention.
hence are subjected to the shock of gun ?re while
Fig. 2 is a diagrammatic perspective View of
trying to perform the di?icult feat of continu
a power limiter adapted for use with the system
ously reproducing the received data as closely as
of Fig. 1.
possible in aiming angles. Our present system 20
of control overcomes this and other disadvantages
of earlier methods of control by rendering the
aiming of the gun entirely automatic under the
control of the received data without any need for
Fig. 3 is a simpli?ed perspective view of a
gun mounted for rotation in train (azimuth) and
in elevation, showing certain of the elements of
the control system of Fig. 1.
Fig. ll is a diagrammatic showing of certain
manually setting angles or performing other 25
details of Fig. 1.
quick change to manual operation under abnor
mal conditions.
shown at the upper left-hand corner are associ
ated with a gun ?re director which may be, for
manual operations at the gun but it permits a
}
Referring now to Fig. l, the apparatus units
In providing a remote control system for an
example, of the type described in United States
object such as a gun, which has high moments 30 Patent No. 2,065,303‘, issued to E. W. Chafee et al.,
of inertia about its rotational axes, we have
December 22, 1936, or which may incorporate
invented features which are particularly adapted
certain features disclosed in the co-pending ap~
to prevent the hunting or oscillation about a
plication of one of the present inventors, H.
position of rest to which such objects are subject.
Hull, joint with W. Hartman and R. Goertz,
One object of the invention is, therefore, to 35 Serial No. 403,618, ?led July 23, 1941. The units
provide automatic control of the aiming of a
shown are those concerned with the transmission
gun from a source such as a ?re-control director.
of the angle 01‘ elevation only, it being understood
.Another object of the invention is to provide,
that similar apparatus may be employed for the
for an object possessing substantial inertia, a
transmission of angle of train (azimuth) data.
remote control system which is free from hunt~ 40 Likewise, at the gun, only elevation control ele
ing tendencies.
ments are illustrated in the ?gure, a similar ar
Another object is to employ, as anti-hunting
rangement for azimuth positioning being im
control terms, functions of the data (represent
plicit in the disclosure.
ing the position of a controlling object) and gun
Gun elevation is represented in the director by
position and particularly time derivatives of the 45 the angular position of shaft 10,5 connected by
variation of these quantities.
gearing to drive the rotors l3 and Ill of Selsyn
A further object is to provide an indication of
transmitters H and I2, respectively, each of said
the functioning of a system of the above char
rotors being excited from a suitable A. C. source.
acter which is in?uenced by the degree of posi
The two rotors l3 and M are driven at relatively
tional disagreement of the controller and gun and 50 di?erent speeds, corresponding to the'ratio of
the rate of change ofrelative position of these
bodies.
gears l5 and [6, to provide coarse and ?ne data
transmission channels, as is common practice in
Another object is to provide a system of the
?re control data transmission systems, a ratio
above character which is fully self-synchronous
of 16:1 between the data amplitude of the two
and free from ambiguity.
55 channels being often employed. The position of
2,408,068
4
3
rotor l3 determines the voltages induced in the
three windings of associated stator H, which
zero Voltage exists simultaneously in windings 24
and 25 is one of unstable equilibrium for both the
voltages are transmitted over three-wire line H’
?ne and coarse channels.
to three-winding rotor it of Selsyn receiver i9,
tion is more fully described in the pending U. S.
This mode of opera
applications of Eric J. Isbister and Francis L.
located at the gun. Similarly, the position of
rotor M determines the voltages induced in the
windings of stator 20, which are transmitted over
three-wire line 29' to rotor 2| of Selsyn receiver
22, likewise located at the gun. Receivers I9 and
22 are operated as locked rotor devices, sometimes
called signal generators since a signal voltage is
Moseley, Serial No. 304,895, ?led November 17,
1939, and of Francis L. Moseley, Eric J. Isbister
and H. B. Steinhauser, Ser, No, 382,020, ?led
March 6, 1941, both assigned to the assignee of
the present inventors.
Voltage limiter 26 comprises saturable reactor
21, across which the output of the ?ne transmis
sion channel is applied, and attenuator 28, the
latter being shown for illustration in the form of
a T resistance network. The voltage induced by
stator 25 across reactor 21 may be adjusted by
suitable choice of the characteristics of attenu
ator 28.
The constants of attenuator 28 and the sat
uration characteristics of reactor 2'! are pref~
generated proportional to the displacement of
each rotor from the datum position. Rotor it,
for example, is connected to generate a gun posi
tion signal by being driven through gearing in
correspondence with gun 23, while rotor 21 is
similarly driven but at a different rate. The term
“synchro transformers” is also applied to devices
such as 19 and 22. It is immaterial in the trans‘
mitter whether the single-winding element, as
erably so chosen that the maximum voltage ap
shown, or the three-winding element be made the
pearing across reactor 2'? is limited to a value
rotor, since only the relative position of the two
which will allow the voltage of stator 24 (of the
elements determines the transmitted voltages.
The voltages in the windings of rotor I8 induce
coarse transmission channel) to take control
an A. C. voltage in stator winding 24, while the 25 when the disagreement between gun and data
voltages in the windings of rotor 2| induce an ' is greater than the‘ range in which the ?ne trans
A. C. voltage in stator winding 25. These two
mission gives correct electrical indication. When
stator voltages, which are both proportional to
a ratio of 16:1 between ?ne and coarse trans
the positional disagreement of gun 23 and shaft
mission channels is used the shifting of control
l0, but in a different ratio, are combined in a cir- I from one to the other should occur before the
diasgreement reaches approximately 121/4 de
cuit which supplies an input to ampli?er-modu
lator 5G, to be later described, and a voltage lim
grees.
iter 26 is connected across the output circuit of
Since the ratio of the ?ne transmission chan
stator 25 for the purpose of shifting control from
nel is 16 to 1, the amplitude of the ?ne alternat
the ?ne to the coarse transmission channel when " ing potential signal would go through sixteen
the disagreement of the transmitter and receiver
' complete cycles for every 360 degree change in
the angle of disagreement between the gun 23
exceeds the range of ?ne transmission.
When the gun and director are in synchronism,
and the director shaft iii.
the voltage in stator winding 25 of the ?ne trans
Were the ?ne trans
mission channel to solely control the position
mission channel is zero. ~Displacement of the di
rector elevation shaft (data) by a small angle in
one direction results in an A. C. voltage being
of the gun, the direction of control exerted there
induced in winding 25 proportional to the dis
placement and having a phase dependent upon
by would only be correct for one-half cycle to
either side of the zero disagreement position.
Accordingly, it is necessary to render ineffective
the control exerted by the line transmission sir,
the sense of the displacement. A displacement
in the opposite direction results in a reversal of
nal beyond such limits.
This limitation of the range of control of the
phase of this voltage. A position of stable equi
?ne transmission signal is accomplished in the
voltage limiter 26 which operates to prevent the
librium is thus de?ned. Considering the coarse
channel, when the gun and director (data) are
?ne alternating potential signal from ever ex
This am
in synchronism the voltage across winding Ed is _ i ceeding a predetermined amplitude.
not zero due to an initial or biasing displacement
plitude is so chosen that the sum of both the
coarse and ?ne alternating potential signals is
which is given the stator mounting this winding
but this initial voltage is balanced out by the volt
age from transformer 30, supplied from the com
potential signal.
mon A. C. source and having a resistance-capacity ; ."
only slight disagreement between the positions of
always of the same sign as that of the coarse
phase. adjustment 3| in its input circuit, which
voltage is made equal in magnitude but opposite
in phase thereto.
the gun and the director shaft, the ?ne trans
mission potential signal exerts the preponderant
control, since the coarse transmission potential
The coarse as well as the ?ne
channel is therefore in stable equilibrium at this
point.
When the gun is positioned 180° away from the
In this manner when there is
signal has not as yet built up to a substantial.
60
magnitude.
High accuracy of following is thus
obtained under these conditions. However, when
the disagreement between the gun position and
the director shaft position is substantial, the
coarse potential signal has built up to a value
which is greater than the limited value of the
synchronous position, i. e., from the angular value
of the data, the voltage in winding 25 is zero, but
the voltage in winding 24 is reversed in phase and
so is of the same phase as the voltage supplied
by transformer 30. These two voltages therefore
?ne potential signal. Thus, correct direction of
do not annul one another and no equilibrium of
the coarse transmission channel results at this
ment, while highly accurate control is obtained
control is obtained for all ranges of disagree
point. The purpose of the voltage supplied from
when the gun and director shaft are in substan~
transformer 36 is thus seen to be to prevent the 70 tial agreement, which latter condition is the nor-i
occurrence of two positions of stable equilibrium
mal operating condition.
in which the controlled object could otherwise
move in synchronism with the controlling object.
It will be found upon analysis that any position,
other than the synchronous position, at which
The circuits so far described provide means I
for obtaining a signal voltage indicating dis
agreement of the gun position and the transmit
75/ ted
data and closely proportional to such dis
2,408,068
5
of the gun position and datum have been dc~
scribed. In addition to this primary signal, as
noted, auxiliary signals are employed. One of
these ‘auxiliary signals is proportional to the rate
of change of the transmitted elevation data, that
is, to the rate of change of position or speed of
turning ‘of shaft l0 and rotors l3 and M. This
signal is supplied as a D. C. voltage by generator
agreement, at least over a limited range, the
phase of the voltage indicating the sense of ‘the
error. This voltage is applied across resistances
32 and 33, which form a voltage divider.
Means for obtaining auxiliary signals propor
tional to other quantities, which we combine with
the disagreement or error signal, will be de~
scribed later.
‘
The voltage drop across resistance 33 is ap
plied to imput resistances I32 and 43 of balanced
10, shown as having a ?eld excited by a suitable
It may be preferable in some in
1.0 D. C. source.
stances to employ permanent. magnet excited
modulator 5B in a vmixer circuit which may be
traced from one terminal of resistance 33 by way
generators for those described herein as D. C.
excited. Generator ‘It is driven by a “chaser”
of lead SE to the outer terminal of resistance 53
and from the other terminal of resistance .33 by
way of resistances 35, 36, 31, 38, 46 and lead 4! .15
to the outer terminal of resistance 42.
Modulator 50 is A. C. operated and comprises.
two triode or other multi-electrode vacuum tube
motor controlled by the elevation data shaft Hi,
here illustrated as reversible two-phase induction
motor ‘H having stator windings 12a and lib, the
units in a push-pull circuit, in which a bias is
a follow-up device 13, comprising roller contact
former winding being constantly excited from a
suitable A. C. source. Motor ‘H is constrained to
follow the motion of shaft I0 through gearing and
supplied to both units by the drop, due to plate
current, across resistance 5|. The input to this
14 and cooperative contact segments l5 and ‘H5
separated by insulating “dead spot” ‘ll. The
phase of the current in winding 12b, which is
shifted relative to that in windings 120, by con»
denser 18, has opposite values depending on which
contact segment roller 14 rests on, thereby pro
viding reversible operation of the motor.' The
output voltage of generator 'lll, which is propor
modulator is a combination of A. C. and D. C.
signal voltages from the mixer circuit and the
output is an A. C. voltage, having components
which, in phase, and magnitude, represent the po
larity or phase and magnitude of the input sig
nals.
The preferred form of modulator shown in Fig.
tional to the speed at which the armature is ro
3. uses A. C. on the plates for converting the D.
tated, is applied across resistor 31 and is filtered
30'
C. signal voltages to an A. C. voltage, the mag
by the resistance-capacitynetwork comprising
nitude of which is proportional to the magnitude
resistance 36 and condenser 19 to smooth out or
of the D. C. input, and the phase of which is
eliminate peaks due to sudden changes of the
determined by the polarity of the D. C.
'
rate of change of the data, corresponding to ac
A modulator may alternatively be used which
celeration of shaft H).
35
is supplied with D. C. on the plates and obtains
The next signal, means for obtaining which
the conversion to A. C. by the use of ?xed A. C.
will be described, is one proportional to the speed
bias between cathodes and grids, it being im
of rotation of the gun in elevation. This is ob"
material whether the constant A. C. is supplied
tained as a D. C. voltage from generator 830 hav‘‘
in the grid or plate circuit of the tubes. The
ing a permanent magnet ?eld or one excited from
output of modulator 50 is passed by transformer . a suitable D. C. source. Generator 8G is driven by
52 to balanced ampli?er 53 which supplies an
gearing, including gears 8|, from gun 33 and
ampli?ed A. C. signal through transformer 54 to
applies a voltage proportional to the speed of
one stator winding 56 of two-phase motor 55,
rotation of the gun across a potential divider
the other winding E1 of which is supplied from
comprising resistances 39 and 39’ connected in
the common A. C. supply of the system. Con 45 series. Resistance 39 has a variable contact 165
denser 58 is for phase adjustment or phase split
by means of which the magnitude of the gun
ting.
velocity signal to be utilized can be adjusted.
Motor 55, through bevel gears 59, crank 60,
Two other signals are employed, one, a D. C.
push-rod BI and power limiter 62, positions stroke
signal proportional to the position of stroke rod
50
rod 63 of a Vickers hydraulic variable speed gear
63 of the variable speed gear and the other, a
34 comprising a pump or “A” end 65, a hydraulic
motor or “B” end 66, and. an electric driving
motor 61. The Vickers gear is well known to per
sons skilled in the art and is described in detail
in United States Patent No. 2,189,823, issued Feb
ruary 13, 1940, in the names of H. F. Vickers and
N. B. Frost and entitled Apparatus for control
ling the movement of heavy masses, The speed
D. C. signal proportional to the rate of change
of position of this rod. If there were no leakage
in the hydraulic transmission and no lost motion
in the gun drive, the position of the stroke rod
55
of the motor or “B” end of this gear, neglecting
would be strictly proportional to the speed of r0~
tation of the gun. In practice, however, there is
a slight lag in the response of the gun to a change
of position of the stroke rod, and while at constant
velocity either the stroke rod position or the gun
leakage, is proportional to the setting of the 60 velocity signal obtained from generator 3i! would
stroke rod 653 which determines the angle of tilt
be suf?cient, in order to care for all transient
of the pump cylinder block and hence the stroke
of the pistons. Since the motor or “B” end 66
directly actuates the gun 23, the setting of the
conditions which might encourage instability, we
prefer to use both signals and, in addition, a
signal derived from the stroke red signal which
stroke rod 63 is proportional to the angular rate 65 is substantially proportional to the angular ac
of rotation of gun 23. A sump for the operating
celeration of the gun.
fluid used in this gear, which is generally oil, is
A variable coupling transformer 90 having a
shown at 68 and a replenishing pump driven by
rotatable winding 9| excited from a suitable A, C.
motor 61 is shown at 69. In operation, fluid cir-v
source through multi-winding transformer 92
culated by pump 65 causes rotation .of motor 36 70 and rotated by motor 55, through gearing 59, in
and of gun 23 driven therefrom through gears 8|.
positional correspondence with stroke rod 63, is
Returning now to the means for generating the
provided with a pair of stator windings 93 and 94
different voltages which control the setting of
in each of which an A. C. voltage is induced cor
the stroke rod of the Vickers ‘gear, the means for
responding to the position of rotor 9 l , the voltages
generating a signal proportionallto ‘disagreement 75
2,408,068
8
7
in windings 93 and 94 being of opposite phase.
In series with each of these two windings there
is connected one of secondary windings 95 and
96 of transformer 92 to supply voltages of con
stant phase.
Windings 93 and 94 feed phase sensitive recti
?er circuits including bridge type recti?ers 91 and
98 respectively. The D. C. output voltage of each
recti?er is proportional to the A. C. input, and
the polarity of the output is determined by the
phase relation of the input A- C. voltage from
93 and 94 to that of the voltage supplied by wind
bined with a voltage of constant phase derived
from the Selsyn exciting source through trans
former IE3’ to obtain a phase-sensitive device as
described in connection with the circuit includ
ing transformers 90 and 92. Recti?cation of
these voltages is accomplished in bridge type rec
ti?ers Hill and H14’ which may be of the dry disc
variety connected in a push-pull circuit. A D. C.
voltage is thus obtained across center-tapped re
10 sistance I05 which is combined in series with a
selected portion of the voltage across resistances
31 and 38 and applied to meter H16, preferably of
ing 95 or 96 as the case may be. The outputs of
the high resistance or voltmeter‘ type. The ad
justment of the voltage derived from the drop
recti?ers 9'! and 98 are serially combined and ap
plied to low pass ?lter H10 across center-tapped 15 across resistance 31, which drop, as has been
pointed out, is proportional to the rate of change
. input resistor 99. V The D. C. output of ?lter I00,
from which A. C. ripple has been substantially
of transmitted data, is made by means of variable
contact 31' while the adjustment of the voltage
removed, is applied across tapped resistance 40
serving as a potential divider.
proportional to rate of change of gun position is
Also driven from motor 55 through gearing 59 20 made .by sliding contact 38', these resistance ad
and I6! is stroke rate generator I02 having a
justments determining the degree to which the
?eld excited from a suitable D. C. source. The
lag error indication is modi?ed by the relative
armature of generator Hi2 being moved in posi
rate of change of gun position and data.
tional correspondence with stroke rod 63, the
The purpose of this arrangement is to cause
generated D. C. voltage is proportional to the rate 25 the meter to give an indication which is a combi
of change of stroke and therefore is substan
nation of the error and the rate of change of
tially proportional to the acceleration of the gun,
the error. In addition to showing the ?delity of
since the stroke position is proportional to the
automatic operation it enables an operator to an
velocity of the gun, as previously brought out.
ticipate the approach of the gun to the correct
This voltage is applied to resistances 35 and 35' 30 position during manual operation and to govern
connected in series as .a potential divider.
his control accordingly.
To summarize, there are applied to the input
of modulator 5i} to contro1 the operation of gun
'
It will be apparent from the above description
that a combination of three signals are applied
to the meter: a voltage proportional to the error
driving means, an A. C. error signal, and D. C.
signals representing director shaft velocity or 35 in following, a voltage proportional to gun speed;
rate of change of data, gun .velocity, stroke rod
and a voltage proportional to rate of change of
position and stroke rod velocity, the two last
the angle transmitted from the director. The
named signals representing substantially gun ve
resistances across which the signal voltage drops
locity and gun acceleration respectively. The
are taken are so adjusted that when the gun 23
purpose of the auxiliary D. C. signals is to over 40 and director shaft ID are rotating at the same
come the eifect of the inertia and other charac
speed the two speed voltages generated by gen
teristics of the controlling and controlled objects,
erators ‘If! and 80 are equal and opposite and
and of the means connecting these objects, in
therefore annul one another.
tending to promote overshooting and hunting of
the controlled object (gun) relative to the angu
lar positions, this object should assume in re
sponse to the data. For a further discussion of
the use of time derivatives of the error signal to
provide anti-hunt characteristics in a remote
control system, reference may be had to U. S.
Patent No. 2,233,415, dated March 4, 1941, to H. L.
Hull, one of the present inventors.
We have described arrangements for causing
'
the gun driving means to be actuated in a pre
ferred manner.
The gun, however, being pos
sessed of high inertia, cannot respond instantly
55
When the gun or
the director shaft changes speed, however, a dif
ference in voltage is produced which represents
the speed of approach or separation of the gun
and datum angle. This resultant signal, when
added to the error signal in the proper relation
ship, causes the meter to "anticipate” future
The degree of “anticipation” provided is
adjustable by means of contacts 31' and 38' and
by moving these contacts to adjacent ends of the
resistances with which they cooperate, meter I06
error.
may be caused to indicate lagonly.
We have found that it is highly desirable to‘
provide certain safety devices in connection with
to change of transmitted data and there will con
the Vickers gear as used in our control system to
sequently be periods when the data will not be
accurately reproduced in aiming angles. The se
prevent excessive hydraulic pressures being built
up and to prevent excessive power demands on
riousness of any such discrepancy depends to a 60 the pump driving means 67. The location of
certain‘ extent upon whether the gun position is
approaching or moving away from they datum po
sition, that is, upon the relative rate of change
of gun position and datum. Accordingly, we sup
these devices in the driving system is shown in
Fig.41 by the block I08, details being shown in
Fig.
.
One safety device is a pair of spring loaded
ply an indication, somewhat in the nature of a 65 pressure relief valves. Normally, outlet pipes
Ill‘! of pump 65 are in connection with corre
?gure of merit of .the system, which combines the
sponding pipes I07’ leading to hydraulic motor
error of gun following with the difference of the
88, and the pressure built up by pump 65 must‘
rates of change of gun position and of datum, the
therefore be su?icient to overcome the entire load
latter term representing the relative rate of
change of the two angles.
70 on motor 58. Under certain conditions, excessive
pressures might thus be built up. To prevent
Transformer I83 (Fig. 1) is connected to re
this, relief valves HI’ and III are provided. As
ceive the voltage across resistances 32 and 33
seen in Fig. 4, valve l i I’, for example, comprises
which is proportional to the error in following.
a ball H2 normally pressed against a spherical
This transformer has two secondary or output
windings and the voltage induced in each is com 75 or frusto-rconical seat by spring H3 thus closing
2,408,068
91
10
pipe H4 leading to one of pipes IIl‘I. When the
mitting motion from arm L24 to cruciform mem
ber I20 (or in the opposite direction) when the
resistance to such motion is insufficient to over
come the pressure 'of spring I28 and open jaws
I25 and I21, which is the case during normal ac~
tuation of rod 63.
pressure of spring I I3 is overcome by pressure in
pipe IM, ball I12 lifts and provides a lay-pass
to the other of pipes Iill. Ball I I5 of valve III is
actuated by oil pressure in the reverse direction
and would similarly provide a passage between
pipes It‘! should the direction of ?uid ?ow be
reversed from that indicated in Fig. 4 and the
pressure built up in the reverse direction between
pipes Ill‘! exceed the maximum allowable pres
sure. Actuation of the valves interconnects pipes
IIl'I and allows circulation of oil at maximum al
lowable pressure by pump 65 without correspond~
ing rotation of motor 5'5.
Several conditions may occur under which the 15
by-passing of pipes lol by valves III’ and III is
essential to the operation of the system as, for
example, when a shift to manual operation is
made by operating transfer valve I80, and when
limit stop valves I40 and I40’ are actuated, as
will be later referred to.
Another safety feature is provided in power
limiter 62, shown in detail'more particularly in
Fig. 2. This device operates to prevent excessive
power demands on the gun driving means, in
cluding the hydraulic transmission, under ab
normal conditions as, for example, when stroke
rod 63 is suddenly given a large displacement.
For modifying the setting of rod 63 (shown in
Fig. 2 in the position for zero stroke) to care for
abnormal conditions, we provide two like cylin
ders I39 and I30’ connected by pipes III] and
H0’, respectively, to pump outlet pipes I 01. A
piston I3! is movable‘ in cylinder I30 under the
in?uence of ?uid pressure transmitted by way
of pipe IIll against the resistance of a compound
spring comp-rising a stiff spring I32 and a con
centric weak spring I32’. Small displacements
of piston ISI are controlled by spring I32.’ where
as both springs I22 and I32’ act in controlling
larger displacements. Piston rod I33‘ extends
from piston I M through the cylinder head and is
normally positioned with clearance between its
outer end and one of the two opposite lateral
extensions of member I29. Cylinder I39’ contains
a piston and spring similar to those described in
25 connection with cylinder Hill. From the piston in
cylinder I39’ extends piston rod I33’ ending a
slightdistance from the other lateral extension
of member I28. Member I28 is not engaged by
either of piston rods I33 or I33’ until a relative
Such a sudden and large stroke rod displacement
calls for a correspondingly sudden and large 30 displacement occurs which is greater than the
displacement of member I28 during normal op
change‘ of speed of motor 66 and, where a high
eration.
inertia load such as gun 23 must be suddenly ac
celerated, tends to cause a severe strain on the
Should, however, excessive pressure be built up
driving means. To prevent this, we provide means
in cylinder I39, for example, piston I3I and rod
for limiting the maximum stroke of the pistons of
I23 will be moved, at ?rst against the relatively
pump 65 responsive to output pressure of the
slight opposition of spring I32’ and later against
the greater opposition of springs I32 and I32’ in
pump, and. since the power delivered by the pump
is proportional to the product of stroke and pres
combination. If this occurs at a time of large
stroke rod. displacement (calling for high ac
sure, we are thus enabled to limit the maximum
celeration and velocity of the B-end) contact is
power which can be delivered at any stroke set
ting and can select a preferred law of variation
made with member I20, stopping further stroke
of this maximum pressure with stroke setting sig
rod movement. Further motion of rod I 33 will
Such a law may be, of example, constant
also cause rotation of this member in a clockwise
power pump output regardless of the input to
motor 67.
If motor 6'!‘ driving pump 65 should be loaded
direction resulting in movement of stroke rod 63
nal.
so as to develop pressures equal to the relief valve
settings, as, for example, if pipes Ill'I should be
completely blocked, the stroke of the pump may,
by our power limiter, be reduced to a value such
that the power dissipated‘ by the pump is well be:
low the normally available maximum power. It is
thus possible even to block rotation of the gun,
as is desirable under conditions to be described,
and maintain maximum pressures in pipes IS‘!
without excessive power consumption or exces
in a direction to shorten the stroke of pump 65
and thus limit the developed power. In moving
rod 63, piston I3I does not have to move rod BI
and thereby operate against the high resistance
of all the elements connected to that rod, since
the resistance of spring I28 is made relatively
low and therefore allows stud I29 to move jaws
I26 and I 21 apart as member I28 is rotated
against the sole resistance of the spring with
out displacing arm I 24 and rod 6 I.
In a manner similar to that described, increas—
ing pressure in pipe HQ’ causes piston rod I33’
eventually to engage‘ member I20 and rotate said
member in a counter-clockwise direction, thereby
to limit the stroke of pump 55 when operating
sive heating of the equipment.
Stroke rod 63‘ (Fig. 2) is shown as operated by
rotation of a cruciform member I29 pivotally
mounted on shaft I22‘, pivoted to datum at I2I. 60 in the reverse direction. . By adjustment of clear
ances and suitably proportioning the relative
The angular position of member I20 in normal
strength of springs I32 and I32’ and of the cor
operation is determined‘ by the setting of push
responding springs in cylinder I36’, a preferred
rod GI, the motion of which is communicated to
law of variation of maximum power may be at
shaft I22 through crank arm I 23‘. A second crank
arm I 2!! is also rigidly mounted on shaft I22. ' tained. Furthermore, a change from one law to
another may be had corresponding to the effec
Arm I24 mounts a pin or stud I25‘which is nor-\
tive change of spring strength brought into play.
mally oppositely engaged by jaws I26 and‘ I 21
mounted for independent free rotation about‘
shaft I22, the two jaws being oppositely pressed
against stud I25 by spring I28. Also oppositely
engaged by jaws I26 and I21 is upwardly extend‘
ing stud I29 mounted on the arm of member I20
opposite to that with which rod 63' connects.
This arrangement of a pair of studs engaged‘ by
spring pressed jaws forms a coupling for trans
Control automatically reverts to stroke motor 55
when abnormal conditions are abated.
A further safety feature is provided in the form
of limit stops preventing overrunning of the gun
in elevation, only, no azimuth stops for gun op~
eration being'normally necessary or desirable.
.These stops cooperate with power limiter 62 and
75 relief valves II I’ and I II to bring the gun to
2,408,068
11
12
stand still without imposing undue strain on the
ported from the gun mount, and. is connected to
driving means or mount.
A pin I35 (Fig. 3) on gun elevation gear sec
tor I64 engages a lever I35, pivoted on the gun
drive a worm or pinion (not seen in Fig. 3) mesh
with pipe I42 leading to transfer valve I80, thus
ings of signal generator rotor I8.
ing with elevation gear sector I64. Elevation
indicator I63 is mounted at the top of column
mount, when the gun reaches the lower limit of U! I59 and comprises a Selsyn receiver I8I' (Fig.
its travel about horizontal trunnion I50. Lever
1) operated as a free rotor device having a stator
I36 operates rod I31 which in turn operates valve
winding I68 excited from the common A. C. sup
rod ‘I38 (Fig. ll) through a crank or other suit
ply and a rotor I 59 on the shaft of which is
able connection. Rod I38 mounts valve piston
mounted indicator dial I18.
I39, slidable in valve cylinder I44, of the valve 10
The windings of rotor IE3 are connected across
I 40, which cooperates with a port I4I connecting
transmission line II’ in parallel with the wind
The position
normally providing a free. connection between
of dial I10 therefore indicates the transmitted
corresponding pipes I 01 and I01’ by way of valves
data and provides a check on the operation of
I40 and I80. When stop pin I35 engages lever 15 the automatic positioning equipment. The indi
I35, piston I39 is moved to the left and gradually
cation of this dial also is used in connection with
obstructs port I 4|, it being seen that piston I38
operating means such as handwheels I64’ pro
is provided with a chamfered edge for obtaining
vided for manual aiming of the gun. Similar
a gradual throttling action. Gradual obstruc
handwheels I52 are provided for manual aiming
tion of port I M causes an increasing pressure to 20 of the gun in azimuth
accordance with data
be built up in one of pipes I01 which eventually
shown by indicator I51.
brings power limiter 62 into play to prevent ex
The shift from automatic to manual operation
cessive demands on pump 65 and motor 51. With
in elevation is made by means of transfer valve
port I III completely blocked, flow of ?uid from the
I80 (Fig. 1.1) having operating knob I8I on valve
hydraulic motor 65, through the lower of pipes 25 stem I82 for displacing pistons I03, I84 and I85
I01’, through pipe I42 and port MI and the
in cylinder I86. Normally, for automatic opera
lower one of pipes I01 back to the pump 65 is pre
tion, pipe I 42 communicates with the lower of
vented and motion of the gun in elevation ceases.
pipes I81’ by way of the space between pistons
The setting of relief valve III’ is normally such
I84 and I85 and similarly, pipe I42’ communi
that when port ' MI is completely closed, this
cates with upper pipe I01’ by way of the space
valve operates to by-pass ?uid between pipes I 81.
between pistons I83 and I34. This is the con
When the elevation data is such as to require
dition shown in the ?gure. For manual opera
the gun to reverse its direction, that is, to increase
tion, knob I8! is pulled out to a position (deter
its elevation, the direction of ?uid ?ow will tend
mined by a stop, not shown) such that piston I85
also to reverse and it is then necessary to provide
completely blocks the opening of pipe I42 and
a. path for a reversed circulation of oil, otherwise
such that the space between pistons I84 and I85
clocked by piston I39. Spring loaded check valve
I45, which is actuated in response to such re
Ierse ?ow, under this condition by-passes valve
I40 until such time as lever I 35 is no longer en
raged with pin I35 and piston I39 returns to its
normal position in response to the pressure of
permits unimpeded flow between the two pipes
I01’. Thus, ?uid displaced by motor 36 during
operation of handwheels I 54’ can circulate freely
40 without passing through pump 65.
The blocking of pipe I42 brings into play power
limiter 82 as in the case of the operation of the
:pring I43.
limit stops which limits the load imposed on
A second pin (not shown) or gear sector I64
pump 85 and motor 31 but allows these units to
Lctuates valve I48’ to prevent overrunning of the 45 continue to operate so that a switch back to auto
run beyond the highest desired elevation angle.
matic operation can be quickly made at any time.
E‘he operation of valve I48’ is in all respects simi~
The pressure developed may be su?icient to cause
ar to that of valve I40 except that the lever op~
the operation of one of relief valves II!’ or III
rated by rod I31’ is reversed, and as primed ref
but the power delivered by the pump will still
rence numerals in Fig. 4 relate members of this 50 be kept by limiter 6?. well below the permissible
*alve to like members of valve I40, its operation
maximum. It is to be understood that in order
rill be readily understood without further de
to maintain the hydraulic transmission in opera
cription or explanation.
tive condition at all times, accessory devices may
In Fig. 3 the manner of mounting certain of the
be necessary such as drainage pipes, etc., as is
ontrol and indicating units at the gun is illus 55 understood by those skilled in the art.
rated, as well as the rotatable mounting of the
Brie?y reviewing the functions of the appa
un itself. Gun 23 is pivoted about horizontal
ratus shown in Fig. 4, a pressure is built up be
runnion I50 for rotation in elevation while plat
tween pipes I01 by pump 55 in one direction or
Jrm I5I on which the assembly of gun and as
the other, depending upon the phase of the com
Jciated units is supported is pivoted about a 60 posite potential output signal of balanced ampli
ertical pin (not shown) for rotation in azimuth.
?er 53. rI‘he direction of pressure and resulting
The azimuth drive is mounted on a hollow col
?uid ?ow indicated in Fig. 4 is that which would
mn I52 supported from platform I5I. The hy
be caused by a signal voltage requiring a de
raulic motor or “B” end of the azimuth variable
crease in the elevational position of the gun.
)eed gear is connected to drive a vertical shaft 65 Under theseassumed conditions the direction
ithin this column mounting a pinion I54 mesh
of ?ow will normally be from pump 65 through
lg with a stationary azimuth gear I55. The
the upper of pipes I81, through limit stop valve
amps or “A” ends of both azimuth and eleva
I40’, through pipe I42’, through transfer valve
on drives are enclosed in a housing I56 which
I 80, and through the upper of pipes I01’ to the
.ay also enclose the stroke setting motors, aux- " hydraulic motor 58. In its return path from the
‘.ary signal generators and associated equip
hydraulic motor the fluid will traverse the lower
ent. Mounted at the top of column I52 is an
of pipes I01’, transfer valve I80, pipe I42, limit
:imuth indicator I51, seen in rear aspect.
stop valve I40, and the lower of pipes I 81 back
The elevation driving motor 66 (Fig. 1) is
to pump 65.
ounted in a housing I 58 on column I59, sup
The transfer valve I80 is provided in order to
2,408,068
13'
.14
completely out off the hydraulic motor 66 from
the ?uid pressure supplied by pump 65, in case
tial signals are introduced into a balanced modu
lator 5!! which combines them into one corre
manual control of the gun is desired. The trans
sponding composite alternating potential signal
fer valve I88 accomplishes this simply by block
ing the path of oil from pipes I62 and M2’ to
pipes lill', respectively, and simultaneously pro
viding an inter-connecting channel between
pipes Hi7’.
which appears across output transformer 52.
This output signal is then ampli?ed in the bal
anced ampli?er 53 and the output applied vto one
phase of a two-phase motor 55, the other phase
of which is constantly energized from a suitable
alternating current source. In this manner the
motor 55 is caused to rotate at a speed and in a
Limit stops M5 and MD’ are provided to also
interrupt the supply of ?uid to motor 66 in case
the gun 23 should reach predetermined limits of
operation. Thus, when the gun has reached its
- lower limit of operation, piston I39 of limit stop
valve M9 is automatically displaced by the mo
tion of the gun to such a position that it blocks
port ilil, thus interrupting the supply of ?uid
direction corresponding to the magnitude and
phase of the. composite alternating potential
signal.
‘
.
I
.
A Vickers hydraulic variable speed unit is pro
vided consisting essentially of electric motor 81’
driving a hydraulic pump 65, the fluid pressure
generated by said pump driving the hydraulic
motor 66 which directly actuates gun
The
speed and direction of rotation of the hydraulic
20 motor 66 and of the gun 23 may be controlled by
to the motor. While the elevation data remains
such as to require that the gun be lowered in
elevation, the direction of ?uid pressure will re
main the same and will tend to cause current flow
the setting of a stroke rod E3 which in turn is
as indicated in Fig. 4. However, fluid flow from
the hydraulic motor will be‘ prevented by valve
directly connected to motor 55 and controlled
thereby. In this manner the composite alternat
Hill and hence valve I I2 will open to by-pass the
ing potential signal controls the direction and
fluid from the pump. Under such conditions it
is apparent that check valve I45 will remain 25 the speed of rotation of gun 23.
closed.
Since the gun is rotated by the Vickers unit
at an angular rate proportional to the setting
However, should the elevation data reverse,
causing a reversal of pressure, check valve M5
of stroke rod t3, the rate of displacement of the
will open, allowing fluid. flow in the opposite
stroke rod may be taken as a measure of the
angular acceleration of the gun. Accordingly,
direction corresponding to increase in the eleva
tional position of the gun. As the gun is thus
direct current generator N32 is actuated in ac
cordance with stroke rod 63, as by being directly
elevated, piston I39 is automatically removed
from port MI by the action of spring :53, and
connected to the same motor 55 as is the stroke
rod. Thus, the voltage generated by generator
the normal conditions of operation of the system
are restored. Limit stop M0’ operates in exactly
"52 is proportional to the angular acceleration
of the gun, and this generated voltage is applied
the same manner as limit stop I49 but becomes
effective upon the gun reaching its upper limit
across resistor 35 to supply that previously re
ferred to component of the composite signal
in elevation.
which is proportional to the angular acceleration
Should the gun become jammed for any reason
or should the transfer switch i811 be set to its 40 of the gun.
As many changes could be made in the above
manual position, it is apparent that the ?uid
pressure between pipes it)? will increase, since
?uid flow will be prevented. In order to prevent
construction and many apparently widely diiler~
responds to the angular disagreement between
relationship between said two objects for pro~
ent embodiments of this invention could be made
this pressure from exceeding a predetermined
without departing from the scope thereof, it is
safe limit under such conditions, the relief valves 45 intended that all matter contained in the above
Ill and iii’ are provided. These valves are set
‘description or shown in the accompanying draw~
so that when the pressure between pipes it‘!
ings shall be interpreted as illustrative and not
in a limiting sense.
exceeds a desired limit, one or the other of these
valves, depending on the direction of the pres
Having described our invention, what we claim
sure, opens, thus providing a direct channel
and desire to secure by Letters Patent is:
between pipes It'l, by-passing the rest of the
1. In a positional control system, a controlling
system, and thus preventing the pressure from
object, a controlled object, means having a one
exceeding a predetermined limit.
to-one relationship between s9‘ . two objects pro
Brie?y reviewing the operation of the entire
ducing an A. C. signal proportional to the posi
system, a synchronous transmission system is 55 tional displacement of saidl two objects and re
provided whereby an alternating potential signal
versible in phase with the direction of said dis
is obtained across resistors 32 and 33 which cor
placement, a second means having a multiple
the gun 23 and the director shaft l9. Two direct
ducing a similar signal responsive to a smaller
current generators ill and 8!! are provided, one 60 displacement in position between said two objects,
being driven in correspondence with the director
said signals normally exercising joint control of
shaft ii! and the other being driven in corre
said controlled object with said second signal
spondence with the gun 23, whereby a direct
preponderant, and means including a saturable
current voltage signal proportional to the angu
reactor connected across said second signal for
lar rate of rotation of director shaft ill is ob 65 limiting the same to a predetermined amount,
tained across resistor 3'1, and a ‘direct current
whereby, When the relative positions or“ the con
voltage signal proportional to the angular rate
trolling and controlled objects exceed a predeter
of rotation of gun 23 is obtained across resistor
mined angle, the ?rst signal prevails and pro“
38. A similar direct current generator 162 is
provided in order to obtain a voltage across re 70 vents loss of synchronism.
2. A positional control system as claimed in
sistor 35 which is proportional to the angular
claim 1, having means for preventing 180° am
acceleration of the gun 23, as will be explained
biguity of the ?rst-named signal control, where
hereinafter.
All of the above signals, comprising one alter
nating potential signal, and three direct poten 75
by complete self-synchronism is obtained.
3. In a system for positioning a heavy object
2,408,068
15
in correspondence with the position of a con-.
troller, means producing an alternating current
signal proportional to positional displacement of
the object and controller, servo means controlled
by said signal for driving the object including a
variable speed hydraulic gear having a variable
binatio-n thereof, and means actuated by said
derived potential for positioning said member.
7. In a system for (positioning an object in cor
respondence with the position of a remote con
troller, means producing a signal proportional
to the positional disagreement of the object and
displacement pim'ip and a hydraulic motor driven
therefrom, said gear having a control memberv
moved in response to the sense and amplitude of
controller, servo means controlled by said signal
for driving the object including a variable speed
hydraulic gear having a variable displacement
said signal and governing, by its position, the 10 pump and a hydraulic motor driven therefrom,
speed of said servo means, and a generator con
said gear having a control member moved in re
nected to said member producing a variable direct
current signal proportional to the acceleration of
said gear for opposing said ?rst signal and a
sponse to the magnitude of said signal and gov
erning, by its position, the speed of said motor, ‘
modulator for combining said signals, the output
driving fluid for limiting or reversing the motion
of said member at high speed positions to limit
and means responsive to the pressure of the
of which controls said servo means.
4. In a positional control system, a controlling
object, a controlled object to be kept in positional
agreement with said controlling object, means for
obtaining an alternating electric potential pro
portional to positional disagreement of said two
objects and reversing in phase in correspondence
with change of sign of said disagreement, means
for obtaining unidirectional electric potentials
respectively proportional to the velocities of said 25
two objects, thermionic tube means jointly re—
ceiving said several potentials as an input and
supplying a reversible phase alternating output
proportional to the combination thereof, an alter
nating current source, and reversible driving
means for said controlled object including a two
the power consumption.
'
'
‘
'
8. In a system for positioning a gun in corre
spondence with the position of a remote con
troller, means producing a signal proportional to
the positional disagreement of the gun and con
troller, servo means controlled by said signal for
driving the gun including a variable speed hy
draulic gear having a variable displacement pump
and a hydraulic motor driven therefrom and op
eratively connected to the gun, and means for
further controlling said driving means in accord
ance with the output pressure of said pump, said
last means including means inversely responsive
30 to the speed of rotation of the gun for adjusting
the displacement of said pump to the power de
phase motor having one phase-constantly excited
from said source and a second phase receiving
the reversible phase output of said thermionic
veloped thereby.
rotatably mounted gun in positional correspond
tuating a hydraulic motor operatively connected
to the gun, displacement adjusting means limit
9. In a system for positioning a rotatably
mounted gun, a hydraulic variable speed gear
means.
35 driving said gun including a variable displace
5. In an automatic system for positioning a
ment pump with operating means therefor ac
ance with a remote controller, means for obtain
ing the increase of power delivered by said pump
ing an electric potential measuring the positional
disagreement of said gun and controller, means 40 with increasegof output pressure, said adjusting
for rotating said gun including a variable speed
hydraulic transmission having a positionable
means having a plurality of degrees of response ,
;o a combination of said ?rst two potentials, and
sequentially effective with increase of pressure,
and a limit stop comprising means actuated by
the gun at a predetermined position in the travel
thereof for effectively blocking the circulation of
operating ?uid between said pump and motor,
the output pressure of said pump being then
neans actuated by said derived potential for po~
modi?ed by said limiting means.
member determining the output speed thereof,
neans for obtaining an electrical potential pro~
portional to the position of said member, means
:‘or deriving an electrical potential proportional
;itioning said member.
6. In a system for automatically positioning a
rotatably mounted gun in positional agreement
avith the position of a remote controller, means
.’or obtaining an electrical potential proportional
‘,o the positional disagreement of the gun and
:ontroller, means for rotating the gun including
it variable speed hydraulic transmission having
2. positionable member determining the speed
hereof, means for obtaining an electrical poten
'
10. In a gun positioning mechanism, a variable
displacement hydraulic pump, driving means for
said pump, a hydraulic motor connected for driv
ing a gun and actuated in accordance with the
displacement of said pump, means controlling
the output .power of said pump with increase of
pressure according to a desired law of variation
over a selected range, said controlling means be
ing di?erently responsive to increase of pressure
over selected portions within said selected range,
and pressure relief means limiting increase of
neans driven from the gun for obtaining an 60 power beyond said range.
HARVARD L. HULL.
:lectrical potential proportional to the velocity
WILLIAM S. GORRILL.
.hereof, means for deriving from said three po
WILLIAM F. FROST.
\entials a further potential proportional to a com
;ial proportional to the position of said member,
Документ
Категория
Без категории
Просмотров
0
Размер файла
1 621 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа