US1165121A

US1165121A - Controlling apparatus.

Info

Publication number: US1165121A
Application number: US85925814A
Authority: US
Inventors: Charles R Pratt
Original assignee: Individual
Current assignee: Individual
Priority date: 1914-08-29
Filing date: 1914-08-29
Publication date: 1915-12-21
Anticipated expiration: 1932-12-21

Description

. C. R. PRATT.

CONTROLLING APPARATUS. APPLICATION r1151) AUG-29. 1914.

1,165,121 Patented Dec. 21, 1915.

4 SHEETSSHEET I.

/M% "6 v z-$07 71. I Md-Wk c. 11. PRATT.

00111110111111; APPARATUS.

APPLICATION FILED AUG-29, 1914.

1,165,121. Patented Dec. 21, 1915.

4 SHEETS-SHEET 2- C. R.,PRATT.

CONTROLLING APPARATUS.

APPLICATION FILED AUG.29. 1914.

1,165,121. Patented Dec.21,1915.

4 SHEET$SHEET 3.

C. R. PRATT.

CONTROLLING APPARATUS.

APPLICATION FILED AUG-29, m4.

Pmimd Dec. 21, 1915.

m orrro.

" R. PRATT, or MoN'r'cLAm, NEW JERSEY.

CONTROLLING APPARATUS.

Specification of Letters Patent.

Patented Dec, 21; 1915.

Application filed August 29, 1914. Serial No. 859,258.

To all whom it may concern:

Be it known that I, CHARLES R. PRA'I'I, a citizen of .the United States, residing in Montclair, New Jersey, have invented certain Improvements in Controlling Apparatus, ofwhich the following is aspecifica tion. 1

One object of my invention is to provide a relatively simple, compact and reliable combination of parts which while being particularly designed for the control and operation of the rudderof vessels 'ofla'rge size, shall be available for use for govern ing the operation of power actuated machines or apparatus such as lntensifiers, elevators or the like.

A further object. of the invention is to provide a novel control ling mechanism for either by a suitable motor or. by'hand;in

the case of a rudder its speed decreasing as it approaches an hard over position. v

Another object of the invention is to provide a novel form of rudderoperating mechanism whose parts shall be so designed and associated that the rudder may be operated at a relatively high speed without increas ing ,the "size of its operating plant, thinvention also contemplating a novel, forrnof follow-up or escapement mechanism with such an assembly of rudder control apparatus that there is no possibility of the va: rious parts getting, out of .synchronism even after prolonged operation. I "I also desire to provlde a novel form'of steering gear in which the parts are so coordinated that the speed of the rudder will vary with'the sea pressure upon it and 1n which when arranged for handsteering the torque on the, steering wheel is kept constant regardless of thesea pressure.

It is also'desire'd to provide means whereby the operating torque on the steering wheel may be readily adjusted to suit the number of men available for its operation.

The invention also contemplates a novel means for maintaining the rudder in any adjusted position, without causing or tend- ,had

- ing to cause leakage of liquid from the hydraulic operatin mechanism, the arrangement of parts belng such that it is possible for said rudder to yield under abnormal conditions without breakage or unduly straining the mechanism associated therewith, after which it is automatically brought back to its original adjusted position.

These and other advantageous ends I secure as hereinafter set forth, reference being to the accompanying drawings in wh1ch;- 1 e v Figure 1 is a plan partly in section illus- -t rating a controlling system designed and constructed according to my invention; Fig.

- 2 is a side elevation also partly in section, of

certain of the apparatus shown in Fig. 1; Fig. 3 is a front elevation. of the hydraulic rams and certain of their associated parts; Figs.'4 and 5 are elevations partly insection oftwoof the automatic controlling devices forming part of, my invention; FigsTG and 7 are respectively aside elevation partly in section and an end elevation showing the detall arrangement of the mechanismfor controlling the" operation of the pumpemployed when the rudder is actuated by'hand power; Flg. 8 is an elevation illustrating the connections between the pilot'motor and its associated mechanism; Figs. 9 to 11 inclusive are elevations partly in section, illusl trating modifications of certain features of my invention, and Fig. 12is a fragmentary elevation showing a slight modification of one of the features of myinvention.

In the above drawings, 1 represents the post of the rudder or other rotary or oscillatory structure which is tobe moved and controlled, and this in'addition to having other supporting structures (not shown) has a bearing .2 in a frame 3 made in the form of one'or more suitably connected castings. To the head of the rudder post is confiected a tiller which inthe present instance c onsists of two parallel arms 4 properly keyed 109 to said post and extending respectively above andbelow a plunger forging 5 whose ends in the form of rams are operative in two cylinders 6 and 7 rigidly clamped to the base or frame casting 3 so as to be in line with each other.

The two arms 4 are formed with radial guideways for blocks or crom-heads 8 mounted on trunnions 9 fiked to orforming it enters the cylinders 6 and 7-, is properly -packed to prevent leakage of liquid. The

'lower trunnion is provided with a down- ,Wardly projecting extension 9 operating in sired or suitable form, I have shown themember 17 as a fiat.disklikestructure co-' operating with a series of spring pressed plugs 18 of suitable dimensions and number operative in cavities of the member 16.

. These plugs are at all times pressed toward the disk 17 by springs 19 so that under ordinary conditions the gear 11 is operatively I connected to .the shaft 13, although under abnormal conditions, it is-free to move in? dependently thereon -by reason of the turning of the disk relatively to the member 16. Also keyed tothe shaft 13 is a worm wheel 20 engaged by a worm-V21 fixed to a shaft 22 on which is also fixed a beveled gear A Worm wheel 23 is loosely mounted ona ,shaft 22in line with the shaft 22 and has fixed to it a beveled gear 24, there being a series of planetary gears 26 mounted on a structure 26 keyed to. the shaft 22 and meshing with both

beveled gears

21 and 25. For actuating or controlling the worm wheel 23 and the parts associated therewith, I provide a pilot motor- 27 to whose armature shaft 28 is fixed a worm 28" operatively engaging the worm wheel 23. The shaft 22 is made in two parts connected through a magnetic clutch 161' and while one part has fixed to it'the gear carrying structure 26 the other part carries a gear 29 meshing with the teeth of a suitably guided rack 30. This is suitably connected at itsgupper end to one end of a lever 31, keyed or otherwise rigidly fixed t the stroke controlling shaft 32 of a variab etstroke pump 33. Theopposite end of the lever 31- is pivoted to a suitable form of centering. device which in the. present case I have shown as including a rod '33 passing through a pair of

plates

34 and 25 beyond the former of which it is provided with a head or stop nut 37, and

between the two plates, concentric with said rod, is confined a spring 38. Also passing through both of the plates are two other rods 39, each of which has a head or nut 40 above the plates 34, and a second nut 41 below the plate 25. Each of said latter rods is connected to a supporting member 42 pivotally carried on any suitable fixed bracket such as the structure indicated at 43, so as to permit. of a slight rocking on the rods 39 and the parts connected thereto A under the action of the lever-.31.

In order to insure springs shall always return the shaft 32 to its'no stroke position when the pilot motor stops, 1 mount the magnetic clutch 161 to separably connect thetwo' parts ofthe shaft 22, and provide it with two independent windings. Of these the one indicated at 1.62 -(l* 1g. 1) is in series \\li,l1 the armature of the motor 27, and current flows to it through that the centering suitable brushes 'r Fig. 4, and suitable slip rings or contacts .(not shown) The winding 163 is connected across theline-conduetors by brushes -;--r, Fig. 4, and suitable slip rings or contacts, though it is in series with a switch whose. movable member 164: is

attached to the lever 31 in such manner as to at all times engage a contact strip 165. .Two other contact strips 166 and 167 are so placed that one or the other of them is connected to the strip 165 whenever the pump lever 31 moves a short distance to either side ,of its zero stroke position.

The driving shaft -56 of the pump 33 is operatively connected to a continuously operative motor 57'through differential gearing 58 which may be constructed as illustrated diagrammatically in Fig. Said gearing is shown as' consisting oftwo beveled gears 59 and 60 respectively keyed to the shaft .56 of the pump and the 'arma ture shaft 61 of the motor 57. This latter shaft has loosely; mounted on it a sleeve 62 having arms on which are rotatably mounted beveled pinions 63 each meshing with the two gear wheels 59 and G0. The arms or.

spindles 64 are journaled in bearings formed ina rotary casing (35 forming part of or attached to a frame'GG constituting a lever one of whose arms has pivoted to it a rod 67 operative-on a centering spring (58. Said rod passes through a pair'of plates 69. and 70 between which the spring 68 is ci'mfinedby a pair. of nuts 71 and 72 and there are also two supporting .rod s 73 passing through the two plates and rigidly connected to a cross bar 74:, which. is pivotally mounted-on any suitable supporting structure (not shown). Each of these rods 73 has a nut 7 5' above the plate 69 and a second nut 7 6 below the plate 70. The opposite end of the'lever 66 carries a suitably insulated contact arm 77 one portionof which is' in constant. engagement with a circularly curved contact strip 73, while a second portion is so formedto be capable of engaging any of a number of contacts 79 between which is connected armature resistance 80 of suitable material. As shown in Fi g. 5 the motor 27 has its. field winding 31 permanently connected between two current supply mains in and 1/ and has its armature normally connected directly to the latter of said current mains and to the mally held in engagement by the centering the contact arm 77 of the lever 66 is norspring 68. Since this arm 77 is at all times in engagement withthe contact strip 78, it will be noted that said armature is ordinarily connected directly across the current supply mains, since the main conductor a: is permanently connected to the strip 78.

As shown in Fig. 1 the

conductors

82 and 83 leading from the brushes of the motor 27 are respectively connected to a hand operated follow-up controller 81 placed on the bridge ofa vessel or at any other desired point. This controller consists of an operat} ing handle 85 carrying two contact plates or brushes 86 and 87 of which the first is designed to be capable of electrically connecting a contact ring 88 with any of the number of contact strips 89,90, 91 and 92 concentrically mounted upon a rotatably mounted plate 93 of insulating material.

Between the segmental strip 91 and the rela tively small contact plates 89 is connected a body of armature resistance 94 and a second body of resistance 95 is likewise connected between the plates 90 and the segmental strip 92. Also mounted on the rotatable insulating plate 93 is a contact ring 96 capable of being connected with either of two segmental contact strips 97 and 98 by the contact 87 on the operating handle 85, it

i being noted thatwhen this latter is in its middle or 011' position corresponding to the amidships position of the rudder, these contacts 86 and 87 do not engage any of the contacts on the rotatable plate 93. This latter is operatively connected by a wire, chain,-

or' equivalent device*-99 with the pulley 12 which is rigidly fixed to and therefore necessarily rotatable with the gear 1.1 on the shaft 13, and the arrangenumt of parts 1s such as render impossible any slipping or relative rotation of this pulley and the.

plate 98.

As shown in Fig. 1 the contact ring 96 is connected through a conductor 101 with,,,the contacts 7 9, while the'contact 97 is connected through a limit switch 102 and the conductor 82 with one of'the armature terminals of the motor 27, this latter conductor being also connected to the segmentalcontact 92. Similarly the,second armature terminal of. the motor 27 is connected' by the conductor 83 to the segmental contact 91 and through a second limit switch 103 with the contact segment 98. The contact ring 88 is connected to the supply main y and .as

before noted the contact strip 7 8 is connectv ed to the supply main w. The two cylinders 6 and 7 are connected through

pipes

104 and 105 to the pump 33 which obviously is intended to be at all times rotated in the same direction by the motor 57, although the direction of the fluid flow delivered bygit will pump 106.

depend upon the direction of movement of the stroke varying shaft 32- and hence of the lever 31. u

. As so far described the steering gear has' included only those parts required for oper-' ating the rudder by power, but if it should {and hence the amountof fluid delivered per revolution maybe varied-at'will. As before,

the stroke varying shaft 109 has connected to it a lever 110 as shown in Fig. 6, and is normally held by means of a spring 111 operating on said lever in a position in which its plungers are adjusted for *full stroke operation. In this case the spring is connected to said'lever through a cap plate 112 which engages one end and its other end is connected to or supported by a second cap plate 113 which may be adjusted toward or from the first cap plate by means of a hand wheel 11-1 having a nut operative to move a short rod 115 attached to the plate 118 either toward or from said spring. The outer extremity of the lever 110 is connected to a three armed or bell crank lever 116 fulcrumed on any suitable support and havingone of its arms connected through alink 117 to one end ofa rotatable frame 118 Whose opposite end is connected to a second arm of said lever through a link 119, a bell crank lever 120 and a link 121. Thisframeis carried by a sleeve 122 .rotatably mounted on the'wheel shaft 123 to which is fixed'the hand steering'. Wheel 12 1. Said shaft has loosely mounted on it a beveled gear 126 to which is fixed a spur gear 127, and, has fixed to it a beveled gear 125. Beveled pinions 128 are rotatably carried on spindles connected to or formed as part of, the sleeve 122, and their teeth mesh with both of the beveled gears 125 and 126. The spur gear-127 .in

turn meshes withthe teeth of a'gear 129 fixed to the driving shaft 130 of the Under conditions of .op'erationand assuming that the rudder is to be operated by power, the electric motor 576s run continuously, but obviously without causing the pump 33 to discharge any liquid, since the centering spring 38 normally holds the lever 31 in such position that the stroke adjusting shaft 32 maintains the pump plum-- gers in ,their no stroke positions. 1 Since there is practically no'resista-nce to the 10- 5 tation of the shaft 56, the difierential casing 58 has practically no tendency to rotate. If now it be desired that the rudder shall be so actuated as to cause the vessel to turn to starboard, the operating handle 1 85 is moved to bring its contact 86 into en gagement with one of the contacts 90 and the contact ring 88,,and also to cause its contact 87 to electrically connect the-contact ring,96 and the segment 98. As a consequence current will flow from the supply main w to the contact strip 7 8. through the contact arm 77 to one ofthe contacts 7 9, and

.thence through contacts 96, 87, .98, limit switch 103, through thearmature of the pilot motor 27, clutch winding 162, conductor 82, contact 92, resistance 95, contacts 90, 86 and 88, and thence to the current supply main y. The motor 2'7 isthus started with all of the resistance 95 in circuit, and its revolution causes turning of the Worm .wheel shaft- 22 and" beveled gear 24:.

Since the power necessary to move the rpdder from its amidships position is necessar11y far in excess of that of the relatively I small motor 27, the worm wheel21 isaprac .tically held stationary and as a result the rotation of the gear-"29 through the; worm 28, WOIIII wheel 23, planetary gears 26 and clutch 161, causes longitudinal movement of the rack 30.and a turning of the lever. 31 through a certain definite angle against the action of the spring 38. This movement of the lever likewise turns the shaft 32 and ad' justs the plungers in the pump 33 so that I liquid is delivered thereby through the pipe 104 to the cylinder 6 and is drawn in through the pipe 105 from the cylinder 7. The plun gen is thus moved-longitudinally in the cylinders and through the trunnions 9 and blocks 8, the tiller arm-3:4; and with them the rudder post 1 are swung to starboard.

, Since the above turning of the stroke varying shaft 32 causes a transmission of power between the motor 57 and the pump 33, there is a relative turning of the difierential casing 58 against the action of the centering spring 68, which results in more or less of the resistance '80 being cut into.

the operation of the worm wheel 20 serves to drive the worm 21 as an escapement device. The torque of the pilot motor on its .7 worm gear is applied to control Iever 31, using the bevel gear attached to worm 21 as a fulcrum. e

The various parts of the device are so designed that thefmaximum torque of the pilot motor (with no armature; resistance in circuit) is just enough 'to fully compress the centering spring'38 and put the pump at full stroke, which drives the'segment 10 and the pinion 11 at maximum speed; the gear ratio being such that it synchronizes with the maximum speed of the pilot motor. Introducing enough resistance into the. armature circuit of the pilot motor to give it torque enough to half compress the centering spring 38, puts-the pump at half stroke and causes "the gear 11 to be driven at half speed, thereby holding back the pilot motor to half speed, which is then its normal speed due to, the amount of resistance introduced into its armature circuit. The pilotmotors normal speed 1S always enough greater than its gear ratio to the Worm wheel20, to cause the worm 21 to drive the worm wheel 20 with all the power delivered by the pilot motor and c' thereby relieve main motor 57 by a come-- sponding amount. This turning of the rudderand hence of the gear 11 turns the plate 93 of the"controller 84c through the chain or wire 99 in such a direction that by the time the rudder has moved through the same angular distance as the angular displacement of the operating han'dle85 from its amid position, said plate has been turned sufliciently to cause the various, contact'strips 98, 88 and 90 todisengag'e the contacts 87 y and 86, thus open circuiting and stopping the motor 27 The rudder is now locked in this adjusted positionindependently of any holdin action which may be exerted by the liquid in the cylinders 6. and 7, for the reason that any normal stress which may be exerted through the rudder post, rack 10 and worm wheel 20 on the worm 21', can not ca use revolution of the same. There is there fore no leak age from the cylinders 6 and 7,

although in the event of any abnormal strain brought to bearupon the rudder and its connecting mechanism,'slipping would occur between the two members'1'6 and 17 of the friction clutch interposed between the gear'll and the worm Wheel 20.'- -It is noted that whenthe above described movement of the lever 31 -c'au'ses its contact 164 to complete the circuit of-the shunt coil 163 of the magnetic clutch, the latter holds said lever in any position to which it may have been brought by the pilot motor, while this is op-- erating. When'said motor stops sald lever is retained under the control of the rudder gears until the rams have nearly stopped moving, at which time the circuit of the shunt coil is opened by' the lever contact 164, thus allowing the centering spring 38: to-return the stroke controlling shaft 32 exactly to its zero stroke position.- The load is thus taken off the motor 57 so that under the action of its centering spring 68, the gear casing orframe 66 is at oncereturned to its normal'position, and the resistance? 80 is again cut out of circuit with the motor 27. It will be noted that the centering spring 38 acting on lever 31, rack 30, pinion 29, shaft I 22, and planetary gear 26, returns pump to zero stroke in the number of revolutions taken by worm 21, which always revolves in a directionopposite to that of the worm wheel driven by the pilot motor, the torque given tothe worm 21 by the spring 38 being such as to cause it to drive the 1 worm wheel 20. Therefore whether increas- 'sition, when by means well known ing or decreasing the stroke of the pump, the worm 21 always drlves the worm wheel-20,

otherwise, and should worm wheel 20 attempt to drive the worm 21, this worm gear wouldjam and stop on account of the angle of the thread of the worm 21, which has friction thrust washers instead of ball or roller thrust bearings. A further movement of the operating handle .85 to the left will agai start the motor 27 and by the same sequen e of operations as above described will causethe rudder to be moved still farther to starboard, it being possible to continue such movement until'it reaches-its hard-over poiii the art, the limit switch 103 would be autgimatically opened, thus stopping the motor 27 and leavingthe rudder locked in said posftion. A

movement of the operating handle in the opposite direction to that above noted will,

likewise cause the same, series of operations as above described, except that in this case the direction of rotation of the motor .27 will be reversed, While the controlling shaft 32 of the pump 33 will be so turned that the plungers of the" pump are caused to dischargeliquid through the pipe 105 to the cylinder 7 and draw it from the cylinder 6 through the pipe 106i. In such case the motor 27. rotates the worm 21 in such a direction as to permit rotation of the gear 11 in a counter-clockwise direction and a movement of the rudder to port, under action of the fluid under pressurein the cylin= der 7. As before, the movement of the rudder will'cause the plate 93 of the controller.

81 to follow up' the operating handle 85-,so

as to open circuit the pilot motor 27' and lock the rudder from further movement,

when the latter has moved into the angular position occupied by the said handle 85.

If it be desired to operate the rudder by hand power, the centering spring 111 is ad justed by means of its hand wheel 114 to apredetermined tension dependent upon the number of men available for operating the steering wheel 124, and if two men are to operate said wheel, power is at first transmitted through the

gears

127 and 129 to the driving shaft 130 of, thepump 106. Since the controlling shaft 109 of this pump is normally maintained by the spring 111 with the pump plungers in their full stroke positions, said pump delivers liquid at its maximum rate of flow through the pipe 108 to the cylinders 7. for example, and draws liquid from the cylinder 6 through the pipe 107, thus causing longitudinal movement of the rams 5 toward the right. The rudder is thus turned to port; for the first part of this movement it swings at a relatively high mains the same, its speed of movement is correspondingly cut down. In spite of the W fact therefore, that as the rudder approaches its-hard'overposition, the work necessary to move it is not increased, it-is still possible for the men operating the wheelr'to perform this work, since the speed of movement of the rudder continues to decrease by the gradual reduction of the length of stroke of the pump plungers. operation corresponds with that occurring It will be noted that this when the rudder is actuated by power. Ob-

viously as soon as movement of the hand wheel ceases the stroke controlling shaft 109 of the pump 106 is automatically returned to its full stroke position by thespring 111 and when the wheel is turned in the opposite direction the sea pressure on the rudder assists in its return tothe amidships position in a minimum of time, since the pump plungers operate at full stroke 1n vi ew of the -relative ease of movement of the driving shaft 130 while the liquid is being permitted to flow from the cylinder 6 through the pump to the cylinder'=7. Obviously when the hand steering gear is employed, the nut on the shaft 13 may be slacked off, thus permitting movement of the gear 11 and its connected parts independently of the pilot motor and the. pump 33. The valves 14:1 and 142 in the pipes-104 and 105 would likewise be closed and valves 143 and 144: in the pipes 107 and 108 opened.

' In the case of the power driving mechanism it will be understoodthat the adjustment of the stroke of the pump 33 is dependent not only upon the operation of the pilot motor 27 but also upon the pressure of the sea upon the rudder, for the movement of this shaft is dependent upon'the resultant of the forces originating from these sources.

If the rudder is in the amidships position,

for. example, the sea pressure is zero and 1f the :pilot motor 27 is started by operation of the lever 85, the constantlyoperating pump 533 as previously described, is at once adjusted so that'its .plungers will operate at the full stroke. If,,on the other hand, the

rudder be in some-position other than amidships', the operation of the pilot motor which would permit said rudder to approach the amidships position has little or no effect upon the stroke varying shaft 32 of the pump 33, since the sea pressure on the rudder permits easy revolution of the worm 21 by the'pilot motor, and the bringing of the rudder to the amidships position largely by the sea pressure. When the rudder has passed beyond the amidships position, the

sea pressure again acts as" a retarding force and since said rudder and hence the worm the rudder is primarily operated, it will be noted from the foregoing description that I have provided means whereby the sea pressure on'the rudder is caused to determine the amount of power delivered from said source. \Vhile the. work done is substantially constant, the speed of movement of the'rudder gradually decreases as it is moved from theainidships to the hard over positions. When the rudder is moving toward the amidships position the work required is a minimum while its speed of movement is a maximum.

' If desired I- may replace the differential mechanism, shown in Fig. 1 as connected between the' motor 57. and the pump 33, by a hydraulically actuated device such as is illustrated in Fig. 9. This consists of a pair of

cylinders

170 and 171, connected by pipes 172'and 173 respectively to the cylinders 6 and 7. Two

plungers

174 and 175 respectively operate in said

cylinders

170 and 171 and are both connected by a link 146 toa lever 147, fulcrumed to a suitable supporting structure and carrying a contact mem ber 77*, which like member 77 (Fig. coacts with the

contacts

79 and 78 as heretofore described. A spring 148 normally holds the lever 147 in such position that all o-fthe resistance 80 is cut out of the armature circuit of the motor 27, but whenever there is fluid under pressure in either of the cylinders 6 or 7, it acts through the pipes 172 and 17 3'to move either one or the other of the plungers thus causing the lever and its contact member 7 7 a to take up a corresponding position against the action ofthe spring 148. As the pressure in the cylinders 6 or 7 rises there is thus introduced'into the circuit of the armature of the motor 27, more or less of the resistance 80, so that the speed of said motor is cut down and its torque is decreased as the rudder is moved from its amidships position,

as previously described. Similarly, the differential mechanism shown in Fig.' 1 as connected between the-hand wheel 124 and the pump 106 may be. replaced by either of the devices shown in Figs. 10 or 11, which inelude a lever 150 connectedto the stroke regulating and reversing shaft 109 of the pump, together with a centering spring 111 which tends to maintain said shaft in its full stroke position. This spring is operative on one arm of the lever whose other arm" is connected through a link 151 to a pair of plungers respectively operative in two

cylinders

152 and 153 which, like the

cylinders

140 and 141 are connected

throughpipes

154 and 155 to the two cylinders (i and 7 respectively. As before any rise of pressure in theram cylinders causes movement of the plungers out of their

cylinders

152 or 153 and the resulting movement of the lever 150 with the partial rotation of the shaft 109 will shorten the stroke of the pump plungers to, a degree eorrespmulmg to the presslu'e, which pressure in any case is dependent on the sea presder 159 containing a cylindrical valve 160.;

In this case the two

pipes

154 and 155 are connected .respectively to the opposite ends of the valve cylinder, so that fluid under pressure delivered from one of; them moves the valve 160 into 'such a position that-free communication 13 established between sald pipe and the cylinder liifi with the results .100

noted in connection with Fig. 10, and similarly, 'fluid delivered from. the other pipe likewise moves the valve topermit flow of said fluid to the said cylinder. The pilot motor requires no break to stop or hold it, as

the centering spring 38 always applies a measured torque load to stop and hold the worm on the armature shaft of the pilot motor. With the pilot motor stopped and the' pump at zero stroke, the worm wheel 20 is locked by its worm 21 whielrwould either have to drive the worm of the pilot m'otou through its worm wheel or would compress the centering spring 38. The worm wheel 20 is therefore locked to resist any torque applied to it by sea. presslu-e on-the rudder through the segment. 10, pinion I11 and the friction clutch. By the use of the centering spring 38; the magnetic clutch 161 and, its associated apparatus, I insure that the lever 31 shall he certainly returned to its exact zero position when the pilot motor stops, and while the stroke of the pump 33' is always under control of said motor the lever is automatically released from the control of the rudder gears when the pump stroke has'been reduced to any predetermined small amount. Ifdes'ired the clutch 161 may have ei-ably less time than would be re ui red toincrease such stroke by the same amount, the

centering spring 38 being free to return the lever 31 to its zero stroke position as soon as the pilot motor circuit is'opened without waiting for said motor -to stop. There is thus a perfect response tothe steering Wheel (or lever) and the follow up Wheel will stop the instant it reaches its off position. Vhile the acceleration of the rudder will not be affected by this clutch releasingapparatus, the stopping time can be reduced to a frac tion of a second Without causing unduestrain to any part. This is'advantagons in case my invention should be employed for training a gun turret lnstead ofactuatlng a rudder and would be available regardlessof whether the control system-was of the follow up orof non follow up type. In some cases spur

gearing

170 and 171 Fig. 12 may be substituted for the Worm gearing in connecting the pilot motor 27 to the gear-24, in Which case the centering spring 38 is free to rotate the armature of sald motor as soon as its circuit is opened, and thusbringthepump 33'to -"exact zerostroke. This action, however, is slower than that of the magnetic clutch by the amount of time required for the pressure of the centering spring to stop and reverse the direction of movement of i the pilot motor.

g 1. lhe combmation of a rudder; a source of power for operating said rudder; and means controlled by the sea pressure on the rudder for varying the force impressed thereon in proportion to its resistance to turning. f 2. The combinatlon of a rudder; a source of'power for operating said rudder; means controlled by the sea pressure on the rudder. forvarying the force impressed thereon 1n,

' proportion to its resistance to turning;

ing means therefor including a variable and meansfor adjusting said force at will.

3. The combination of a rudder; operatstroke pump; and means controlled by the sea pressure on the rudder for varying the stroke of the pump.

4. The combination of a rudder; operatingmeans therefor including a variable stroke pump and amotor for continuously operating the same; and means controlled 1 ing means. therefor including a variable by theseapressure on the rudderfor varying the stroke of the pump. I I

' 5. The combination of a rudder; operating means therefor including a variable stroke pump; a pilot motor; and means controlled jointly by said pilot motor and by the sea pressure on the rudder for automatically varying the stroke of said pump.

' 6. The combination of a rudder; operatstroke pump; with means for/automatically adjusting the stroke of the pump in accordance with the position and. direction of movement of the rudder.

' 7. The combination of a rudder; operating means therefor including a continuously operating variable stroke pump; a pilot motor; means for manuallycontrolling said pilot motor; and means controlled by the sea pressure on the rudder and cooperating with the pilot motor for automatically varying the stroke of the pump.

8. The combination of a rudder; operating means therefor; a pilot motor for controlling said operating means; and a device for. governing" the pilot motor;

9. The combination of a rudder; operating means therefor; a pilot motor for controlling said operating means; a controller for said motor; and floating gear connecting the rudder and said controller.

- 10. The "combination of a rudder; operating means therefor; a pilot motor for controlling said operating means; a follow-up controllerfor governing the pilot motor; and

floating gear connecting the rudder with a movable element on said controller.

1.1. The combination of a rudder; operat-' ing means therefor; and a device independ- .ent of said means for automatically locking means.

14. The combination of a rudder; operating mean's therefor; "and locking means for said operating means constructed to operate as an escapement device for following-upthe operating m'eansf 15. The combination of a rudder; operating means therefor including cylinders. and I p-lungers; a continuously operating variable stroke pump connected to the cylinders; and a pilot motor for adjusting the stroke of said pump at will.

.16. The combination of a rudder; operating means therefor; an'escapement device for said me a'ns; and a pilot motor connected to actuate the escapement device and'control the operating means.

17. The combination of-a' member to be operated; operating means therefor an escapement device for said means; and a pilot motor connected to actuate the escapement device and control the operating'means.

18. The combination of a' rudder; means device for following-up said operating.

including cylinders and plungers for operating said rudder; With adevice independent of said parts for automatically locking the rudder in any given position, and controlling apparatus for the operating means connec'ted to automatically release the locking means.-

19. The combination of a rudder; operating means therefor; means for locking the rudder in any given position; and a device connected between the rudder and said means and capable of yielding under abnormal stress.

20. The combination of a rudder; operating means therefor; means for automatically locking the rudder in any given position; and a friction clutch adjusted to slip under abnormal stress upon the rudder, connected between said rudder and said locking means.

21. The combination of a rudder; operating means therefor; worm gearing operatively connected to the rudder; andv a pilot motor operatively connected tosaid gearin 22. The combination of a rudder; operating means therefor including a variable stroke pump; Worm gearing operatively connected to the rudder; a pilot motor operatively connected to said gearing; and means for causing the operation of the pilot motor to vary the stroke of the pump.

23. The combination of a member to be operated; operating means therefor includmg a variablestroke pump; Wormgearing operatively connected to the member to be =op'erated; a pilot motor operatively con-- -nected to said gearing; and means for causing operating of the pilot motor to vary the stroke of the pump.

24. The combination of a rudder; operating means therefor lncludmg a variable stroke pump; worm gearing operatively connected to the rudder; a member for varying the stroke of the pump; and a differential gear connecting said member, the pilot motor .and the worm gearing.

25. The combination of a member to be operated; operating means therefor including a variable stroke pump; vcormgearing operatively connected to the inember to be operated; a member for varying the stroke of-thepu'mp and a differential gear connecting said member, the pilot motor-andthe worm gearing.

26 The combination of a rudder; operat ing means therefor including a variable stroke pump: a member for varying the stroke of said pump; a pilot motor; and means including a differential gear connect- -ing the pilot motor. said stroke varying member and the rudderf 27. The combination of a rudder; operating means for the rudder including cylinders and plungers; a continuously operative variable stroke pump connected to the cylinders; a toothed segment connected to the rudder; worm gearing; means including'a friction clutchv connecting said gearing wlth said segment; a member for varying the,

motor for driving said pump; a pilot motor for controlling the pump; and a device de: pendent upon the load on the pump for controlling the operation of said pilot motor.

29. The combination of a rudder; operating means therefor including a pump; a member for driving said pump; a pilot motor for controlling the pump; and means connected between the pump and its driving motor for automaticallygoverning the operation of the pilot motorp 30. The combinationof a rudder; operating means therefor including a pump a motor for driving said pump; a pilot motor for controlling the pump; and a device dependent upon the load on the pump for varying the torque of the pilot motor.

31. The combination of a member to be operated; operating means therefor including a pump; a motor for driving said pump; a pilot motor for controlling the pump; and a device dependent upon the load on the pump for varying the torque of the pilot ing a differential gear for connecting said pump and its motorg'a pilot motor for controlling the pump; and a device actuated by said differential. gear for varying the currentfloiv in the pilot motor.

34. The combination of a rudder; means for operating the same. including a. variable stroke pump; a motor for varying thestroke of the pump; and means including a differential gear for governing said motor.

The combination a member to be operated; actuating means therefpr; a pilot motor controlling said means; and means dependent on the torque of the pilot motor for governing the actuating means. F

36.- The combination of a member to be operated: actuating means therefor; a pilot motor controlling said meanls; means dependent on' the torque of the pilot motor for governing the Y actuating means; and means for varying the torque of the pilot motor.

37. The combination of a. member to be ing means; a

operated;-.actuat ing means t'herefor; a pilot motor for controlling sai means; .and apparatus including dillerential gearing for controlling? the actuating means and said-f f rlnging the pump to'exact zero stroke when the pilot motor ceases operation.

\ .39; The combination of ,a pump; means for varying the stroke thereof, a device tending to. bringthe stroke varying means to'its zerotposition; meansincluding a pilot motor for actuating the: stroke varying means to increase the stroke of the with a'device for insuring the return'of the stroke varying means to an .exact'zeroposition' after it -has been moved therefrom,

403The. combination of a vari,able .stroke pump a motor actuated. by fiuid from 'the pump a' pi'lot motor;- stroke varying means or the pump; connections between the fluid motor, the'pilot motor and the stroke varymatically, disconnectingthe 'flu id' motor from the stroke varylng means under. pre-' determined conditions. Th

for t device tending to center the strokevarying means;- and means for auto- I.

I 0f tWOfSllbSCrlblIlE witnesses.

e-combinationof a yar'i'able stroke- ;pump a motor actuated fluid' from the a pilot motor; stroke varying means e pump connections between the fluid motor,,the ,pilot motor and the stroke .vary

mg means; a spring for centering'the stroke varying means; and means for permitting action of the spring when the p lot motor ceases operation. v-

p 42. The combination of a variable stroke pump; a motor actuated by fiuid from the pump; a pilot motor; stroke'varymg means for the pump connections between the fluid motor,'- the pilot motor;-and the stroke varg;

.ing means; means for centeringthestro e 1 tch included in'the yarying means; and a clu connections between the pilot motor andthe J stroke varying means.

43. The combination of a variable stroke pump; a motor actuated by fluid from the --p u1np; a pilot motor; a. stroke varying de- 7 vice for the pump;-connections'between the fluid motor, the pilot motor and the stroke varying means; stroke yarymg clutoh miclrcmt means for centering the means; with a magnetic stroke varying means.

In testimony whereof, I have name to this specification,

with the pilot motor and connected between'thefluid' motor and the