US 2448778 A
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Description (OCR text may contain errors)
Sept 7, 1948 G. w. CRISE 2,448,778
AUTOMATIC BOAT- STEERING MECHANISM Filed NOV. 23, 1944 Patented Sept. 7, 1948 UNITED- S TAT ES iAT ENIT O FF'IY'CE AUTGMATIC BGALT-STEERIN G MECHANISMv George W; Crise, Columbus, Ohio Application November 23, 1944; Serial No. 564,828
(Cl. S18- 489) 9 Claims. l
This invention relates to automatic steering means for boats, and its principal object is to provide an automatic means; responsive Vto variations of a magnetic compass needle for maintaining aboat on a given course;`
Automatic steering mechanism for this purpose of prior designs is structurally complicated and costly to install, inasmuch as'such prior apparatus is usually'controlledby gyroscopic means or in another form utilizes electronic tube apparatus and-light-se-nsitive devices.v In brief, such prior apparatus is used primarily on large ships or vessels and is ordinarily incapable of being structurally' simplified to permit of proper usage thereof on' small privately owned motor boats, sailing craft, etc.
Accordingly, it is the aim of the present invention to provide simplified automatic steering mechanism'adapted for popular usage on small water craft and wherein the power required to actuate the apparatus may be obtained from standardV storage batteries, such as those commonly used in connection with the enginestarting and lightingI systems of popularly priced, privately owned motor boats.
For a further understanding of the invention, reference is to be had to the following description andthe accompanying drawing, wherein:
' Fig'. 1 is a` diagrammatic View, partly'in side elevation and vertical section, of my improved automatic 'boat steering mechanism; v Fig. 2 is a plan View of the compass casing;
Fig. 3 is'adetail perspective view of the upper end "ofthe compass needle elevating stem;
Fig. 4 is a` fragmentary vertical sectional view taken onnthe plane'indicated on the line 4 4 of Fig. 1.
Fig. 5'is'a fragmentary sectional View taken on the plane of the line'5-5 of Fig. l.
Referring more particularly to the drawings, the numeral 5 designates the steering Wheel or helm of a boat, thefsame being employed to operatethe boat rudder, not shown, through the usual interrelated controls. To the radiating spokes of this wheel, there is secured as at 6'a belt ring 1, and over thisring there is passed an endless belt, or other equivalent power transmitter y8.' Also, the belt yis trained over a sheave 9 rotatably mounted on the armature shaft I0 of a reversible electrical motor' I I. tachably connected with the helm so that the latter may be either manually or automatically rotated.
The split field I2 of the motor has twoopposing coils-I3 and I4which,th'rough selectiveexcita- The ring 'I is de- 2. tion, cause the armature shaft of the motor torotate in opposed directions. In connection' with this motor, the present invention utilizes compass governedv circuit-controlling apparatus which functions to produce, rst, Irotation of the motor shaft in one direction so that the steering wheel-5 of the boat and its associated rudder will be turned to produce a desired change in the course the'boat is following. However, the rotation of the motor in-this iirst direction is necessarily greater than tha-t which is desired. To alter the` `course or heading of the'boat, as is common in the steering ofsmaller boats, a correction is made, as is usually done when manually steered by immediately thereafterreversingthe direction of rotation of the helm', in thislcase by reversing the direction ofjthe rotation ,of'the-v motor II, in order to bring the steering' wheel back to its original heading, or only'- partially `so,` as may' be desired,`
Therefore, in accordance with thepresent invention, my improved apparatus'functions to rotate the steering 'wheel first in one direction and immediately thereafter in the opposite direction whereby due'f compensation is lmade in the .course which the' boat is to pursue.
In attaining-this end,'use is made of a compass casing comprising a base section I5 having an annularupstanding side wall I6, and on the upper'edges of which wall there is seated a rotatably adjustable cover section Il, the outer margins of said cover section being provided with degree graduations of a full circle. The base section is formed axially withan opening in which is slidably mounted a sleeve I8 fixed to the upper end of a'stem I9, the-lower end of said stem being formed with the core 2il=situated for travel within the field 'coil- 2| of a-solenoid 8. The sleeve I8 is vertically slotted as at 22 to receive a bridge member 23A which forms a stationary part of the base section I5." Centrally, thisbridge member is-provided' with an upstanding bearing point 24, and on the" bearing point there is mounted for turning movement aliftable magnetic needle 25.
At one end, the needle 25'c'arries a conical con- 'tact 26` and, at its other end, on theopposite side of the point 24, is a transversely disposed contact bar 21. The cover section" I'I, which is usually formed from a transparent dielectric material, is provided with'a 'pair of xed arcuate contacts 28, the latter being seatedy in a socket 29 formed in the cover section, sothat the Vlower surfaces of the'contacts A28 will lie in a horizontal plane iiush with that of the lower or inner surface of said *cover section. A'thin strip of Bakelite, 0r other linsulating materia1'30; is' placed between the contacts 28 to electrically separate the same and yet maintain close spacing thereof. On the opposite si-de .of the cover section Il, there is provided a single arcuate contact element 3| which is adapted to be brought into engagement with the bar 21 when the needle 25 is elevated by the eX- citation of the solenoid coil 2| simultaneously with the engagement of the conical contact 26 of the needle with one or the other of the arcuate contacts 28.
The contacts 28 are provided with terminal screws 32, while the contact element 3| is provided with a single terminal screw 33, the headed ends of said screws being accessible from the top of the compass casing- As a source of electrical energy, I employ a standard storage battery B of from 6 to l0 volt capacity. Leading from the positive terminal of this battery is a conductor 34 which extends to one terminal of a small direct current motor 35. A second conductor 36 extends from the other terminal of this motor-back to the negative side of the battery B, thus completing the circuit of the motor to maintainthe same in constant operation as long as the hand switch 31 remains closed. -The armature shaft 38 of the motor 35 is provided with a yworm 39 which meshes with a worm gear 40 xed on the rotating operating shaft 4 I of a timer mechanism T.
Rotatable with the shaft 4I is a cam 42 and, also, mounted on the shaft 4| is a second cam 43. rThe lifting face 44 of the cam 42 is disposed, during rotation of the shaft 4I, for engagement with a roller 45 carried on one end of an arm 46. The intermediateportion of this arm is pivoted as at 41 to thel frame 48 vof a reversing switch R. The end ofthe arm 46 opposite to that carrying the roller ,45 is provided with a suitably insulated resilient strip 49 which carries at its outer end acontact 50, the latter being united by an extensible conductor 5I with the conductor 36.
It will ybe seen thatwhen the face 44 of the cam 42 contactsv the roller 45, the arm 46 will be oscillated about its pivot 41 to elevate-the strip 49, thus bringing the contact 50 vof said strip into engagement with an adjustable contact screw 52 carried by the frame 48.of the reversing switch.
The screw 5'2 is joined by a conductor 53 with one side of the coil 2I of the solenoid S, While the other side of the vcoil 2| is. joined by a conductor 54 with the battery conductor 34, thus energizing the solenoid circuit and creating a magnetic field lwhich draws the core 20 of the solenoid upwardly, carrying with it the stem I9 and the sleeve I8, so that the magnetic needle is lifted and brought into engagement with one or theother of the arcuate contacts 28v and the stationary contact element 3|. l
A conductor 34a extends from the conductor 34 to the terminal screw 33 of the contact element 3l, while leading from the terminal screws 32 of the arcuate contacts 28 are conductors 55 and 5,6. These conductors lead to Contact elements 51 and 58, respectively, which are carried by a suitably insulated rocker arm 59, the latter being intermediately pivoted as at on the frame 43 of the reversing switch. The outer end of the arm 59 carries a roller 6I which rides on the peripheral edge of the cam 43. When the roller 6| is in engagement with the lift region 62 of the cam 43, the contacts 51 .and 58 are maintained in engagement with the upper endsl of a pair of contact screws E3 and B4 of the insulated frame 48.
When the roller 6I is in engagement with the depressed or dwell portion 65 of the cam 43, the
contacts 51 and 58, by gravitational or spring action on the part of the arm 59,'are maintained in engagement with the lower ends of a second pair of contact screws 66 and 61 on the frame 48. The screws 64 and 66 are joined with conductors 58 which lead to the field coil I3 of the motor II, while the screws 63 and 61 are connected with conductors 69 which lead to the eld coil I4 of the motor |I.
In the operation of the apparatus, the switch 31 is closed to energize the motor 35, thereby causing timed rotation of the shaft 4 I. When the face 44 of the cam 42 contacts the roller 45 on the outer end of the arm 46, the latter is lifted to bring the contact 50 into engagement with the frame-carried screw 52, thus completing the circuit of the solenoid coil 2| and elevating the core 28 and the associated stem I9 so that the magnetic needle 25 is raised, bringing .the conical contact 25 thereon into engagement with one or the other of lthe arcuate contacts 2B, and the bar 21 of said needle into engagement with'the contact element 3|. This permits current to travel by way of the conductor 34a to the contact element 3|, thence through the needle 25 to, for eX- ampley the contact 28 with which is connected the conductor 55.
Fur-ther assuming that the parts arein the position disclosed in Fig. 1, current will travel from the conductor 55 through the contact 51, terminal screw 53, conductor 69 to the coil I4, passing from said coil by way of a conductor 1I] through the commutator 1I of the motor II and thence by way of the conductor 36a and conductor 35 to the return side of the storage battery. This excitation of the motor Il causes its rotation in one direction, revolving Withit the steering wheel 5 of the boat.
The rotation of the motor l in the iirstv direction is continued until the roller 6 on the rocker arm 59 drops into the dwell portion 65 of the cam 43, wherebythe rocker arm, by gravity or spring action, is oscillated so that the contacts 51 and 58 arezmoved out of engagement with the ends of the terminal screws 63 and (i4` and broughtinto engagement with the ends of the terminal screws AE36 and'. If current is passing through the con- .the roller 45 of the arm 46. When so freed, the
arm 46 by gravity or by ,spring action, drops and breaks the circuit to the `solenoid S so that the compass needle is lowered and the circuit to the motor .Il interrupted. The cams 4'2 and 43 may be relatively adjusted, through the actuation of the threaded thumb nut 12 on the shaft 4I, so that the cam 43 will reverse thedirection of ro#- tation of .the steering motor II at any predetermined time' relation with respect to the cam 42, thereby causing the steering motor to turn the wheel 5 and then returnthe wheel to its original dead-ahead position, or lto return it only part way, as may be desired.
The rotatable cover section of the compass vneedle casing is provided with spaced depending studs 13. These `studscarryqresilient strips.
5 ofivlinylite or the like which serve to. yieldably arrest deilection of theenergized needle.
l, Automatic boat-steering mechanism comprising al reversible steering control-operating motor having` a pair of polarity-changing eld coils, a compass switch forgoverning selectively theexcitaticncf said field coils, saidswitch embodying acasing having mounted vtherein a pivotally movable north-seeking magnetic needle, a stationary Contact on said `casing engageable with one end ofsaid needle, a pair of electrically spaced stationary'conta-cts,carried by said casing and engageablewiththe o-ther end of said needle, a supportfor said needle normally maintaining the lattergout oi engagement with said contacts, conductors leading from said pair of contacts to said fieldmoils, areturn conductor leading from said motor to a source of electrical energy, a conductor extending from said energy source to said single stationary contact, electrical means operable when energized Ato actuate said needle support to bringsaid needle into circuit-completing engagement with a pair of said contacts with which the needle registers immediately prior to such engagement,l a circuit for the electrical means actuating theneedle support, and a timing switch for intermittently opening.Y and closing said last-named circuit.
2., Automatic boat-steering mechanism cornprising a reversible steering control-operating motor` having a pair of polarity-changing iield coils, a compassV switch for governing selectively the excitation of said eld coils, said switch `embodying a casing` havingmounted therein a pivotally movable north-seeking magnetic needle, a stationary Contacty on said casing engageable with one end of said needle, a pair of electrically spaced stationary contacts carried by said casing and engageable with the other end of said needle, a support for said needle normally maintaining the latter out of engagement with said contacts, conductorsleading from said pair of contacts to said field coils, a return conductor leading from said motor to a source of electrical energy, a conductor I extending from said energy source to said single stationary contact, electrical means operable when energized to actuate said needle support to bring said needle into circuit-completing engagement with a pair of said ycontacts with which the needle registers immediately prior to such engagement, a circuit for the electrical means actuating the needle support, a timing switch for intermittently opening and closing said last-named circuit, and a reversing switch actuated by said timing mechanism for alternately energizing the field coils of said motor while the compass switch needle maintains a given position of circuit closure.
3. Automatic steering mechanism for marine craft comprising a reversible steering controloperating electric motor, the latter being provided with a pair of polarity-changing field coils, a compass switch for governing the controlled excitation of said coils, said switch embodying a casing comprising a base and a contact-carrying member adjustably mounted on said base, a magnetic north-seeking needle pivotally mounted for turning movement in said casing, a stationary contact on said casing memiber engageable with one end of said needle, a pair of electrically spaced stationary contacts carried by said casing and engageable with the other end of said needle, a movable support for said needle normally maintaining the latter out of engagement with said sentada @conductor leading.V from @schuf Said pairofcontacts to one oi-said field coils,y a return conductor.` leading from said motor to a, sou-ree ctelectricalenergy, a conductor extending from said energy source to thesingle stationary contact, a solenoid ,operative Awhen energizedfto yactuatesaid needle supportl to advance said needle into. circuit-completing engagement with apair of said contacts withwhich theneedle registered immediately prior toy the energizing of the, solenoid,` an operating circuit for `said solenoid irl-.- cluding. saidenergy source, and a periodically opcratinqswitcli in said solenoid circuit for intermittently energizing and deenergzing the solenoid.l
4. Automatic steering mechanism for marine craft comprising a reversible steering controloperating electric motor, the latter being provided with a pair of polarity-changingA eld coils, a compass 'switchlfor governing the controlledexcitation of saidcoils, said switch embodying a casing comprising a base and a contact-.carrying member adjustably, mounted on said base, a magnetic north-seeking needle pivotally mounted for turning movement in said casing, a stationary Contact on saidcasing member engageable. with one end of said needle, a pair of electricallyl spaced stationary contacts carried by said casing and engageable with the other. end of said needle, a movable support for said needle normally maintaining the latter out of engagement with said contacts, a conductor leading Yfrom ea-ch of'said pair of contacts to one of said -leld coils, a return conductor leading from said motor to a source of electrical energy, a conductor extending from said energy source t'c the single stationary conta-ct, aI solenoid voperative when energized to actuate said needle support to advancev said needle into circuit-completing engagement `with a pair of said contacts with which the needle registered immedi ately priorto theenergizingof the solenoid, an operating circuit for vsaid `solenoid including 4said energy source, azperiodically operating switch 4in said solenoid'fcircuit for intermittently energizing and'deenergi'zing the solenoid, and an intermittently operating reversing switch cooperative with the conductors leading from said compass switch to the field coils of said motor for alternating the excitation of said field coils when said motor circuit is closed by the operation of said magnetic switch.
5. A compass switch comprising a casing formed to include a base, a contact-carrying member rotatably mounted on said base, a needle support including a stem movably carried by said base, a north-seeking magnetic needle pivotally mounted for free turning movement on said needle support, a relatively stationary contact on said adjustable casing member adapted for engagement with one end of said needle, a pair of electrically spaced contacts carried by said adjustable member engageable with the other end of said needle, a solenoid cooperative with the stern of said needle support and operable when energized to advance said needle into circuitcompleting engagement `with a pair of said contacts with which the needle registered immediately prior to the energizing of the solenoid, an operating circuit for said solenoid including a source of electrical energy, and a periodically operating switch mechanism for intermittently opening and closing said solenoid circuit.
6. In boat-steering mechanism, a reversible control-operating electric motor having a pai-r of polarity-changing eld coils, an operating circuit for said motor including a source of electrical energy, a compass switch positioned in said circuit, said switch including a movably mounted north-seeking magnetic needle, a timing mechanism embodying an electric motor, a circuit for the timing motor leading to said energy source, rotatable primary and secondary cam elements driven by said timing motor, a movable switch arm carrying a pair of spaced contacts cooperative with said primary cam element to alternately energize the iield coils of said reversible motor at timed intervals, a second movable switch arm engageable with said secondary cam element for bringing the same into and out of engagement with a stationary contact, solenoid means operable when energized to advance the needle of said compass into a position of circuit closure, and a circuit for said solenoid means opened and closed by the movement of said second switch arm.
7. In an automatic course-maintaining apparatus for rudder equipped craft, a reversible electric motor for governing the operating positions of the rudder` of such a craft, said motor having a pair of polarity-changing field coils, an operating circuit for said motor including a source of electrical energy, a compass switch positioned in said circuit, said switch including a movably mounted north-seeking magnetic needle, a timing mechanism embodying an electric motor, a circuit for the timing motor leading to said energy source, primary and secondary cam elements rotatable unitarily about a common axis and driven by said timing motor, means providing for the adjustment of said cam elements axially with respect to each other and for maintaining their positions of relative adjustment, a movable switch arm carrying a pair of spaced contacts cooperative with said primary cam element to alternately energize the field coils of said reversible rudder motor at timed intervals, a second movable switch arm engageable with said secondary cam element for bringing the same into and out of engagement with a stationary contact, solenoid means operable when energized to advance the needle of said compass into a position of circuit closure, and a lcircuit for said solenoid means opened and closed by the movement of said second switch arm, the adjustment capacity of said cams being such as to cause the operation of said reversible motor to swing an associated rudder through a greater arc of movement in its course-corrective movement than in its return movement.
8. In an automatic steering system for dirigible craft, a reversible electric motor for actuating a swinging rudder of such a craft, an operating circuit for said motor, a north-seeking compassactuated switching means positioned in said motor circuit, a motor reversing switch in said circuit, and motor driven means for actuating said reversing switch, said latter means including a pair of switch-actuating elements adapted for rotation in unison and adjustable with respect to each other to produce a longer period of rotation of said reversible motor in one rudder-actuating direction than in the other.
9. In an automatic course-maintaining apparatus for rudder equipped craft, a rudder control, a reversible electric motor for actuating said contro1, an operating circuit for said motor, a compass switch positioned in said circuit, said switch including a rotatably mounted and vertically movable north-seeking magnetic needle, spaced contacts carried by said switch and forming a, part of said circuit, intermittently operated electro-responsive means for lifting said needle at predetermined intervals into positions of engagement with said contacts, and spaced yieldable means for limiting the oscillatory movement of said needle.
GEORGE W, CRISE.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,993,549 Holmes Mar. 5, 1935 1,993,550 Holmes Mar. 5, 1935