US2579172A - Propeller pitch reversing control switch - Google Patents

Description

DeC- 18, 1951 L. J. BoRDELoN PROPELLER FITCH REVERSING CONTROL SWITCH 2 SHEETS-SHEET l Filed March 3l 1949 INVENTOR. fans/rencel J. orde/o/l BY Y v nmwzy I .JQ BORDELON 2,579,172 PROPELLER FITCH REVERSING CONTROL SWITCH Filed March 3l, l49

D ec. 18, 1951' 2 SHEETS- SHEET 2 GOV EEN OR /7/- l @lL/'37- T l /74 [53 a I /aa- DI! 52 PROPELLER? f Y fw Powelz Sw: my Y f5; ifi g 44 Y 523164/ 2 ,06 H3 M0 JNVENTOR.

I pRoPeLLEn j 43 awry/7C@ c/. OfO/e/O/Y Revexzsme com l Tlzox. swrrcH 3- Bxf PRESSURE FTE- 1u SW'TC ATTORNEY position.

Patented Dec. 18, 1951 PROPELLER PITCH REVERS-ING vCONTROL SWITCH Lawrence J. Bordelon, San Diego, Calif., assignor to Consolidated Vultee Aircraft Corporation, San Diego, alii., a corporation ofDelaware Application March 31, 1949,'Serial No. 84,565

11 Claims. (Cl. 20d-153) This invention relates to hydraulically actuable controllable pitch propellers and more particularly to improved control means for eiecting the operation of a propeller of the character ndicated.

An object of the present invention resides in the provision of a propeller pitch controlsystem having control devices for attaining pitch reversal of the propeller blades.

Another object of this invention is to provide an electrical control instrumentality of improved construction operative to control the movements of the blades of a hydraulically actuated propeller into and out of reverse pitch positions.

Another object of the invention resides in providing a control instrumentality of the character indicated having the operation .thereof under the control of the usual engine throttle lever.v

Another object of the invention lies in providing an electrical control instrumentality embodying a plurality of electric switch units and electromagnetic switch means electrically associated and all being operative by a common actuating means.

A further object of the invention is the provision of an electrical control instrumentality for controlling the operation of a reversing type hydraulically actuable propellerwhich is of simple, compact and eiiicient construction.

Other objects and features of the present invention will be readily apparent to those skilled in the art from the following specication and appended drawings wherein is illustrated a preferred form of the invention, and in which:

Figure l is a perspective view of an electric control instrumentality in accordance with the'invention.

Figure 2 is a vertical sectional view through the instrumentality.

Figure 3 is a detail view in perspective illustrating the actuator arrangement for the electric switch units of the instrumentality.

Figure 4 is a detail view in perspective showing an armature and associated movable contact assembly for use in the electric control instrumentality of Figure 1.

Figure 5 is a diagrammatic view showing a hydraulically actuated controllable pitch "propeller and a pitch reversing control system associated therewith.

Figure 6 is a diagrammaticillustration of the electrical control instrumentality showing the relative positions of the Various operatingelements for moving the propeller into reverse pitch Figure 7 is a View .sirnilf-Iv t0 iere. d but with the operating elements illustrated inthe relative positions assumed when the propeller is being maintained in reverse pitch position.

Figure 8 is another diagrammatic View of the electrical control instrumentality showing the positions of the operating elements when the propeller isbeing moved from reverse pitch to normal position.

Figure 9 is a diagrammatic View showing the static positions of the operating elements of th electrical control instrumentality; vand Figure 10 is a wiring diagram of the reverse pitch'control circuit .-shown in association with thefeathering control wiring circuit for the propeller. l A

Particular reference is now directed `first to Figure', wherein is shown an aircraft power plant comprising an internal combustion engine, generally indicated at II); which engine I0 is equipped with a hydraulically actuable controllable pitch propeller II. Propeller II has a propeller hub I2 to which is movablysecured a plurality of propeller blades I3 adapted to rotate about their .longitudinal axes to change their pitch angle or angle of attack. Suitable hydraulic pitch chang.- ing mechanism, indicated generally at I4, is containedfwithin a dome YI5 and includes a'piston I6 reciprocablein a cylinder I'I. Piston ISiSmade to move within its containing cylinder Il by the force exerted by hydraulic iiuid supplied under pressure to the opposite ends of the cylinder I'l. Piston I6 is suitably operatively connected tothe propeller blades` I3 through a rotatable member I8 carrying gear means I9 which are adapted to mesh with usual beveled gear means. (not shown) provided on the inner orvbase ends of the propeller blades I3." The piston I6 is joined'to the rotatable member I 8 through a cam follower-cam track arrangement 20 for effecting rotation of member I8 upon reciprocating movement of the piston I6. .This organization of elements acts to convert reciprocable` movement o'f piston I6 into rotative, pitch changing' movement ofv the propeller blades. I3. For a more detailed description of the arrangement of the propeller blades and the .operative Vconnection thereto of the actuating vmechanism reference maybe had to UnitedStates Patent No'. 2,'361,954,'issued November '7, 1944 for Propeller Control Means.

A suitable governor 2| conveniently mounted on the engine I0 acts to supply iiuid to pitch changing mechanism I4 to automatically'effect adjustments `in propeller blade pitch necessary to maintain .constant engine speed under varying Hightv .'conditionsThe' fluid provided by the the governor 2| is adapted to operate to pass oil through conduit 22 to the inboard side of piston I6 to provide pressure tooause` the propellerv blades I3 to move to a lower pitch whereupon engine speed increases.

With an 'overspeed con'- dition the governor 2| will respond to directvoil through conduit 23 to the outboard side of piston I6 to cause propeller blades I3 to move to a higherv pitch, thereby decreasing the engine speed. The particular construction ofthe governor 2|, it is understood, forms no part of the present invention as it is contemplated that such usual governors may be employed as are adapted, in response vto external conditionato cause fluid to be .passed to lone or the other of the two conduits 22 and 23 connected to the pitch changing mechanism |4. The governor 2| may convenientlyassume the form and construction' as fully described in a manual entitled Propeller Hydromatic Governors No. 123, published by .Hamilton Standard Propellers of East Hartford, Connecticut. Associated with governor 2| 'and vthe controllable pitch propeller lI is a control system, indicated generally by the numeral 25, which is adapted to accomplish movement of thepiopeller-blades I3 Afrom their .normal range 'to their reverse pitch positions. Positioning' of the propeller blades. I3 in reverse pitch serves a primary desirable .function in reducing airplane landing -speeds and runs. The attainment of this condition must Vbe rapid, efficient and certain and the control system 25 provided by this linventionis all this.

The control system `25, ras shown, includes ka suitable gear type pump 26. drivenbyan electric motor 21. It is here noted tlriat: this pump 26 used in 'the reversing operation is the same pump which is used for the feathe'rmg operation, so the reversing operation does not require a separate pump. A fluid line 28 connects the inlet of pump 26 with the sump of fthe oil tanky 3| which may be the source of supply for 'the engine lubrication system. The pumpl is connected through a conduit 32 to the governor 2| wherebyauxiliary oil is supplied Vto the governor V2"I "to supplement the normal cil output of the governor, which supplemented oil output is directed by the governor to the pitch control mechanism I4 for use thereby during feathering, unfeathering., reversing'and unreversing operations of the propeller blades. I3.

Associated with the governor 2| cand adapted to aiect the oil supplying voperations 'thereof are a solenoid valve member 33 and a pressure switch 34. The solenoid valve33 lis of 'a suitable constructionv adapting it to direct the Aow of high pressure auxiliary oil from conduit 32 so that it, in a manner well known in the art, `supplements the pressure of the normal oil provided by the governor 2| on either the inboardor the outboard side of the piston I6 as-required to change the angle of the propeller blades` I3. The. pressure switch 34 is provided to stop the loperation of the pump 26 when the oil pressure in propeller cylinder I-| builds up to a predetermined value.. '.The pressure switch 34 lisoperatively connected to L actuation of the switch 38 the propeller governor 2| so that the oil pressure diierential across the propeller piston I6 is duplicated in the pressure switch 34, thus when the oil pressure in cylinder II builds up to the cut-out value of switch 34 after the completion of either a propeller feathering or a propeller reversing operation the switch breaks the electrical circuit to the motor 2'| of pump 26, in a manner and through the use of various mechanisms to be hereinafter described in detail, to close ci the auxiliary pressure being provided to the piston Iii and return the pitch changing mechanism to the normal control of governor 2|.

A usual relay 35, 'electrically connected to the electric motor r2`| through a conductor 35, directly controls the now of current to the motor 2i for energization and deenergization thereof.

Carried by a propeller blade I3 is a slip ring 31 `oi usual construction, which slip ring is connected to an electrical instrumentality or propeller reversing'control switch 33. The slip ring 31 serves `to disrupt the current supply to the feather relay' to deenergize the feather pump motorV 2 to shut off the Aflow of auxiliary oil from pump 26 when the propeller blades I3 have returned to positive pitch after an unreversing operation has occurred. This operation Ywill be described in complete detail hereinafter.

A battery 4|, or any other primary current supply source, is provided to supply the power for use in the operation of the control system 25.

The Vpropeller reversing control switch 33 constitutes the primary control member in the control system 25 in that it controls the now of current from the battery M into the system. The solenoid valve 33, pressure switch 3A, relay slip ring 31 vand battery 5| are all electrically connected to the propeller .reversing control switch te respectively through conductors 32, $3, ed, i5 and 46. The exact construction of switch 38 will be described in complete detail later.

In order to eiect reversing of propeller i i there 4must be an 'actuation of the propeller reversing control switch 38, vand 'in the present invention, is accomplished through a suitable manually operated throttle control lever dl'which is provided with an arcuate cam surface 63 adapted to engage with and oper'- ate the switch 38. The throttle lever di is Vutilized 'for operation of the switch 38 since it is a control member conveniently located for easy reach by the operator. It is'to be understood that the particular construction of throttle control lever il forms lno 'part of this invention, as the invention contemplates the use of any usual engine throttle which can be associated with the propeller reversing `control switch 38 in a manner to permit the manual force applied to the throttle to be trans-- mitted to the .switch 38 to actuate the latter.

Referring now to Figures 1v to 4 inclusive, the construction of the electrical instrumentality or propeller reversing control switch 38 is therein illustratedand as shown comprises a metallic cas ing or housing 5I, formed with its ends and bottom open and having side walls 52 and 53 and a top wall 54. To effect a closed structure the ends are closed by suitable cover plates 55, only one of which is shown, and a base 56 of molded insulating material is tted across the bottom opening. Suitable studs 51 threaded into the side walls 52 and 53 secure the cover plates 55 and base 56 in place.v

Extending downwardly from the top wall 54 and inwardly, substantially centrally, from side wall 52 is a wall enlargement 58' having'v surfaces formed thereon against which generally L-shaped insulating members 6| can be disposed. Mounted `within housing 5|, one on each side of the wall projection 58, is a pair of similar unitary switch units 62 and 63. The switch units 62 and 63 are of` the snap-acting type and include a pair of 'contacts 64 and 65 in spaced relationship and a movable contact member 66 operable between these contacts but normally being biased into en- .gagement with one of the contacts such as 64. The particular construction of the switch units is not a part of this invention. For convenience these switch units 62 and 63 may be of the type described and claimed in Patent 2,237,705 to E. F. Kohl. For actuation in each switch unit of the snap-acting movable contact member 66 out of engagement with contact 64 and into circuit making engagement with opposed Acontact 65 thereisl provided an outwardly biased operating pin 61, which pin projects from the switch enclosing casingl and is 'adapted to be depressed to provide the operating force for member 66.

`To individually actuate the operating pins 61 of the switch units 82 and 63 there is located within the housing 5| and mounted between the units 62 and 63 an actuator arrangement 68, the construction of which is best shown in Figure 3. As there illustrated the actuator arrangement 68 comprises a pair of pivotal lever means 1| and 12. Lever means 1i comprises a pair of generally L-shaped arms 13 and 14, which arms are pivotally mounted at their upper ends by a pin 15 upon a depending portion or projection 16 provided by the top wall 54 of casing 5|. At their free ends the arms 13 and 14 rotatably support -a roller element 11. Projecting from arm 14 and integral therewith is an extension 18 which is bent to one side at substantially a right angle to arm 14. It is this projection 18 which is adapted to engage and depress pin 61 of switch unit 63 upon pivotal movement, in a clockwise direction, of lever means 1|.

Lever means 12 also comprises a pair of generally L-shaped arms 8| and 82 which are mounted at one end for pivotal movement on wall portion 16 by the pin 15 and are disposed so that arm 8| lies outside of arm 13 and arm 82 lies outside of arm 14 of the lever means 1|. The free ends of the'arms 8| and 82 also rotatably support a roller element 83. Formed on arm 8| is a projection 84 which is bent over to extend to the outside of arm 8|. Projection 84 is adapted to contact and move pin 61 of switch unit 62 for operation of this switch unit.

Disposed within housing 5| opposite from switch units 62 and 63 and adjacent side wall 53 is an electromagnet 85 comprising a core 86 with an energizing coil 81 disposed thereabout. A stud 88 passed through top wall 54 is adapted to be threaded into core 86 to secure the electromagnet 35 against the interior surface of top wall 54. A lock washer and nut assembly 9| carried onstud 88 positions and maintains the stud in a ldesired positionas will be discussed in further detail hereinafter.

Associated with electromagnet 85 is a movable contact carriage assembly 92 having an armature `member 83 extending beneath the electromagnet 85 for cooperation therewith. Movable contact carriage assembly 92 comprises a bracket member 94 having a plate-like portion 95 to the upper surface of which the armature 93 is secured by studs, or in any other well known manner. The bracket member 94 includes a pair of upstand- Zing arms `96"and '91' through whichthebracket member 94 is pivotally mounted by a pivot pin 98 upon a wall portion |0| depending from the top wall 54. Upwardly bent from the portion 25 are a pair of lugs or ears |02 which are provided to support rotatably a roller element |03. To the under face of bracket member 94 is suitably fastened a pair of rectangular insulating blocks |04 and |05, with insulating block |04 disposed intermediate bracket 94 and block |05. Supported in horizontal alignment by the insulating blocks |04 and |05 are a plurality of generally L-shaped conducting pieces |06, |01 and |08, each having one leg |09 disposed and tightly pressed between the insulating blocks |04 and 05, and having a free leg extending downwardly from the support aiorded by the blocks |04 and |05, with appropriate contact. faces ||2 being carried by these free legs As shown in the drawings the ends of legs |09of conducting pieces |06, |01 and |08 extend beyond their engagement by blocks |04 and |05 to provide attachment points for electrical leads. The depending legs of the conducting pieces |06, |01 and |08 are adapted to engage and disengage a plurality of contact members mounted on and extending from insulating base 56 for making and breaking electric circuits therethrough. As indicated on the Wiring diagram of Figure 10 conducting piece |06 cooperates with a stationary contact member 3, central conducting piece |01 is engageable with a pair of stationary contacts ||4 and ||5. and conducting piece |08 makes and breaks a circuit through stationary contact member 6. The various stationary contacts ||3, I4. 5, and ||6 comprise flexible upstanding portions ||1 to perm-ita slight sliding engagement with contact faces ||2 for the purpose, as is well known in the art, of lessening any tendency to burn or pit of the contacts.

A resistor member ||8 is mounted through a bracket |2| on side wall 53 of housing 5| and lserves to limit the amount of current passed to the energizing coil 81 of the electromagnet 85.

Located adjacent and above resistork ||8 is a stop member |22 formed by an integral portion bent outwardly from bracket |2|. Stop member |22A is adapted to be engaged by the armature member 82 to determine the extent of movement of this member away from the eleotromagnet 85. A usual wire spring means |23 having a portion thereof wound around pivot pin 98 and with one end bearing upon bracket member 94 and the other end positioned against the inner surface of top wall 54 biases the contact carriage assembly 92 for movement in a clock-wise direction, as viewed in Figures 1 and 2, to move the armature member 93 against stop |2| and normally to maintain the depending legs of pieces |06, |01 and |08 disengaged from their respective cooperating stationary contacts.

, There isincluded in control switch 38 a mechanism for moving pivotally the contact carriage assembly 93 and the two lever means 1| and 12 of actuator arrangement 68. This mechanism includes a reciprocal elongated plunger |24 extending through the top wall 54 of housing 5| and into the housing 5| to lie disposed between .the actuator arrangement 68 and the contact 'aflixed a generally cup-shaped washer member .|26.4 Aspring|21 encircling theoutwardly disposed portion of plunger |24 and having one end .seated against washer |26 and the other against Vthe housing '5| exerts its bias-to urge the plunger |24 outwardly from casing 5|.

The portion of plunger |24 disposed within casing and extendingV below the lower end of bushing member |25 is provided with a generally V-shaped circumferential camming ridge |28. va large diameter portion |3| which is connected through a slope to a small diameter portion |32,

which latter portion in turn is connected by a sloping portion to a projecting portion |33, extending directly downwardly .from small diameter portion |32. Camming ridge |28 being of larger diameter than theiower end of bushing |25 prevents the removal of the plunger |24 through the top wall 54.

For reciprocal operation of the plunger |24 an actuating arm |34 is provided which is pivotally mounted at one end |35 to a generally U-shaped mounting bracket member |35 suitably secured as by stud. means |31 tothe top wall 54. The free end |38 of arm |34 carries a generally U-shaped bracket |4| which rotatably supports a rollerv |42. Rollei' |42 isvadapted to be engaged bycam surface 430i throttle control lever 41 to ellect pivotal movement, in a counter-clockwise direction, of the arm |34 toward the housing 5|. To the undersurface of arm |34 is secured one end of. a leaf .spring .element |43. The iree end of spring element |43 bears against a projection '|45 provided at the outer end of plunger |24. Spring element |43 functions as an over-travel device 'in the transmittal of motion from arm |34 to plunger |24. .To adjust the position of the free end of arm |34 use is made of the stud 88 Ywhich. mounts the electromagnet 85 within casing .5 yStud 85 is adapted to project through a keyhole slot |45 inarm |34 so that its head |46 may engage the upper surface arm |34 and apply a holding force .thereagainst Stud 88 will permit the roller ,|42 .to .be adjusted to the best position for cooperation with cam. surface 48 onthrottle control lever 41.'V

, Reference will now had rto the wiring diagramof Figure 10. `This iigure illustrates the .incorporation of tlie reversing control system 25 with-the feathering control system for. the propeller li. Combining the two systems permits the utilizationby both control systems cicertain of the sameY devices, such as the solenoid valve 33, pressure switch 34, relay 35, the electric motor driven pump 25, and the propeller blade slip ring 31.

. Further provided to complete-the feathering control system are a push-pull electric switch |46 .contact |52 in either direction from its normallycontacts disengaged position into circuit-making engagement with the 4various contact sets of switch |46. The hold-in coil |54 functions to maintain actuator |53 `in its depressed or in position. Hold-in` coil v|54 is electrically connectedat one end to contact |5611l and isV con- .n'ectedv at .its other end byV electrical lead |55 to ground throughimessureswitch 34.

The double-pole relay |41 embodies a pair of switch arms |56 and |51 and an energizing coil |58 operatively connected to the switch arms |56 and |51 for movement thereof from their nornially open positions into circuit making positions. The double pole relay |41 and the pushpull switch are electrically interconnected with switch arm being connected through leads |53 to contacts |49a and |491), switch arm l|51 being connected by lead |6| to contact |56a, and coil |58 being connected at one end to contact |5|a through lead |52. The other end of coil |58 is joined by lead |63 to blade brush |64. Blade brush |64 is adapted to cooperate with contact segments |55 and |55 when propeller blade i3 rotates to complete a circuit to ground for purposes to be described.

Switch arm |55 on energization of coil |58 engages contact |61 of relay |41 which is connected by appropriate electrical leads |68 to pump relay 35. It is noted that one of these leads |53 extends between contact |5|b of `pushpull switch |45 and pump relay 35, connecting to energizing coil |53 of the relay.

Switch arm |51 on energization of coil |56 moves into engagement with stationary contact |1| which. connects through lead |12 to solenoid valve 33.

Direct current power to the push-pull switch V|45 is provided through lead |13 which connects to both contacts Idea and |481). This power may be taken from any primary current supply source, and, conveniently could be led from battery 4|.

The electric connections from propeller reversing control switch 38 to the various devices re.- quired to effect reversing of the propeller will nowy be discussed.

Lead 42 interconnects the solenoid valve 33 with movable contact arm 65 of switch unit 53. Contact 55 of switch unit 53 is connected by conductor |14 to contact Yiwhich cooperates with conducting piece $68 of Vmovable contact carriage 92. Stationary Contact 55 of `switchunit 53 is connected by lead 45 to battery 4| which in turn is connected through an appropriate lead |15 to contact |15 of relay 35. Contact |16 is adapted to be engaged by movable contact |11 on energization of coil |53y to complete a circuit through lead 35 to pump motor 21. Stationary contact 55 or switch 63 is adapted to be connected also to normally engaged stationary contact 54 of switch unit 62 by a lead |18. Oppositely disposed contact 55 connects through .lead |81 to switch unit 53 and thence through lead 42 to solenoid valve 33.

Pressure switch 34 is connected to one. end of energizing coil 31 of electromagnet 85 by lead 43. This same end of coil 81 is then connected by flexible lead |82 to conducting piece' Hi8.V The opposite end of coil 81 is connected by flexible lead |83 to conducting piece |01. A nexible lead `|54 connects conducting piece |56 to switch unit 62. Stationary contact ||3 which is engageable by movable conducting piece |65 is connected by lead .44 to energizing coil |69 of4 relay 35. Stationary contact i4 engageable by lconducting piece |61 connects through lead |66 to resistor IIB which latter is connected to power supply lead 45 by a lead |35. Stationary contact ||5 is also engageable by conducting piece |61 to complete a circuit through appropriate leads |63 and |85 to blade `brush |64 of the slip ring. as-

sembly 31. It is' understood that push-pull switch |46 and double-pole relay |41 do not enter into the control of the reversing and unreversing movements of the propeller l They are included merely to complete the feathering control system to illustrate that feathering control of propeller I and reversing control of propeller I involves common use of a substantial number of control elements to avoid duplication of parts.

Since the feathering of propeller is incidental to the present invention this operation will be described only briefly. To effect feathering of propeller the actuator button|53 is depressed. This will energize coil |59 of relay 35 to close the circuit to motor 21 to start operation of pump 26. Hold in coil |54 is also energized by current iiowing therethrough to ground through pressure switch 34. Pump 26 continues to supply iiuid to governor 2| to cause it to provide preslsure to the outboard side of piston I6 to rotate propellerblade segments 3 toward high pitch and feather position. As soon as the position is reached mechanical stops, not shown, in well known manner halt the blades and cause the pressure in the governor to build up to a predetermined value, at which the pressure switch 34 is adapted to cut out and break the circuit therethrough. This results in de-energization of holdin coil |54 and actuator |53 returns to its neutral position whereby the pump 26 stops and the feathering operation is completed.

To unfeather propeller the actuator |53 is manually moved in the reverse direction to cause movable contact I52 to bridge contacts |48a, |49a, l|5|la and |5|a. With the bridging of these contacts coil |58 of relay |41 is energized by completion of a ground through brush |64 resting on contact segment |66. Arms |56 and |51 move to circuit making position to energize solenoid valve 33 and relay 35. Fluid will then iiow from pump '26 through governor 2| to the inboard side of piston I6 to rotate propeller blade segments |3 to assume a low pitch angle. When a predetermined blade angle is attained an insulated portion on slip ring 31 is presented to brush |64 to break the circuit to relay |41, deenergizing it and inactivating pump 26.

Propeller reversing and unreversing-operations will now be described. Assuming the propeller I I to be functioning in normal, or low pitch, condition the propeller reversing control switch 38 will have its operating parts disposed in the positions illustrated in Figures 1, 2 and 9. As seen pivoted arm I 34 will be in its upper position, as will plunger |24. Roller |03 carried by contact carriage assembly 92 will lie adjacent large diameter portion |3| of plunger |24 and beneath cam.- ming ridge |28. Roller 11 of lever 1| will be disposed contiguous small diameter plunger portion |32, while roller 83 of associated lever 12 abuts plunger projection |33.

When it is desired to reverse propeller the throttle control lever 41 is operated to move cam surface 48 upon roller |42 carried by pivoted arm |34 to rotate arm |34 toward the top of casing 5| of reversing control switch 38. This movement of arm |34 applies a force to the upper end of plunger |24 to move it longitudinally, against the bias of spring |21, into casing 5|. As plunger |24 moves rectilinearly toward base 56 the lowermost roller 83 will ride from projection |33 onto small diameter portion |32 to actuate switch unit 62, camming ridge I 28 will engage uppermost roller |03 to position armature 93 adjacent coil 81 and intermediate roller l11 will ride upon large diameter portion |3| 10 before camming ridge |28 passes beneath upper roller |03.

Reference should now be had to Figure 10 to describe the results of the actuation of plunger |24. Riding up of lowermost roller 83 onto small diameter plunger portion |32 will pivot lever 12 to cause projection 84 thereon to depress actuating pin 61 of switch unit 62. This will cause movable contact 66 to move from contact 64 into engagement with opposed stationary contact 65. Engagement of uppermost roller |03 by plunger camming ridge |28 rotates contact carriage assembly 92 to position, as stated, armature 93 adjacent coil 81 and, further, to bring conducting piece |06 into engagement with stationary contact ||3, conducting piece |61 into engagement with stationary contacts and ||5 and conducting piece |08 into engagement with stationary contact ||6. With contact ||4 engaged by conducting piece |01 current can be supplied through resistor ||8to energize coil 81 of electromagnet 85 to hold armature 93 in closed position and thereby maintain contact carriage assembly 92 in actuated position. Intermediate roller 11 riding onto large diameter plunger portion 3| pivots lever 1| to cause projection 18 thereof to depress actuating pin 61 of switch unit 63. This causes movable contact arm 66 to engage stationary contact 65 of switch unit 63 to complete the circuit to solenoid valve 33. Furthermore current can now flow from movable contact arm 66 of switch 4unit 63 through lead |6| to movable contact arm 66 of switch unit 62, from which it passes by way of lead |84 through engaged contacts |66-||3 to lead 44 and then to coil |69 of relay 35. Relay 35 now functions to energize motor 21 to run pump 26 to begin the operation of reversing propeller At this point the relative positions of the elements of reversing control switch 38 are as illustrated in Figure 6. Pump 26 directs a ow of oil through the governor 2|,and through line 22 to the cylinder I1 at the rear of piston I6 to effect rotation of the propeller blade segments |3 into reverse angle position. At the end of the reversing operation pressure builds up to a predetermined value to actuate pressure switch 34 to break the circuit through electromagnet coil 61 to release armature 93 thereby permitting contact carriage'assembly 92 to rotate under the bias of spring |23 into its neutral position. This causes conducting piece |06` to separate from stationary Contact 3 to break the circuit to relay 35 to inactivate pump 26, Solenoid valve 33 remains energized Vthrough switch 63 and serves to hold the propeller in its reversed position. Figure 7 is illustrative of the relative positions of the elements of reversing control switch 38 when propeller is reversed.

To unrev'erse propeller `and return it to normal-position the throttle control lever is operated to disengage camming surface 48 from roller 48 on arm |34. This permits plunger 24 to move upwardly under the bias of its spring |21. In this movement ofplunger |24 intermediate roller 11 will ride off of large diameter plunger portion 3| permitting lever 1| to be rotated away from switch unit 63 under pressure of the outwardly biased pin 61 of switch unit 63. Contact arm 66 thereupon disengages contact 65 and returns 4to its 'normally engaged position on stationary contact 64. This results in the breaking of the circuit to solenoid valve 33. Cam |28 engages uppermost roller |03 to Il rotate contact carriage assembly 62 to effect engagement betweenv the conductinglpieces" |06, |01 and |08 and their cooperating contacts H3, ||4, I5 and I I6. Power will'then be supplied to energizing electromagnetic coil 81 through resistor ||8 and contacts ||4 and |01 to cause coil 81 to hold armature 93 adjacent thereto and thereby maintain contact carriage assembly 92 in rotated position. Normally ground for the coil 81 is provided through lead 44 and pressure switch 34. However in the event that pressure switch 34 fails to .bev in closed position either because of a pressure surge in the flow lines or because the throttle was moved so fast that it did not have suicient time to close a secondary groundis provided.v This secondary ground is had through lead |02, engaged contact elements |06 and ||6, lead |14, movable contact arm 66 of switch unit 63p lead 4,2 and then through solenoid valve 33. This insures that acircuit is provided for the coil 81 for maintaining the contact carriage assembly in operated position.v

Further upward movement of plunger |24 now permits lowermost roller 83 to travel from small diameter plunger portion |32. This relieves the pressure on pin 81 of switch unit 62 permitting the pin 61 to move outwardly and rotate lever 12. Movable contact arm 66` now disengages contact 55 and re-engages stationary contact 64 to complete a'circuit from battery 4| through engaged conducting piece |06 and contact ||3 to lead 44 and to coil |69 of relay 35. Relay 35 now energizes motor 21 and starts pump 25. This stage the positions of the elements oi reversing switch 38 are as illustrated in Figure 8. Oil pressure will now be routed by the governor 2| through line 23 to cylinder |1 to the outboard side of piston I6, Piston |6 moves to rotate propeller blade segments |3 into positive normal thrust angle. When the propeller segments I3 reach positive pitch contact |65 of the slip ring assembly 31r engages brush |64. This results in shorting out of electromagnetic coil 81 through contact ||5, conducting piece |01, lead |86 and lead |63. armature 9,3 and permits contact carriage 92 to return under spring biasA to its normal position. as shown in Figure 9, to` disengage conducting piece |06 and contact I3 to interrupt the circuit to relay 35 and stop pump 26 and thus return the system to its normal condition.

While certain preferred embodiments of; the invention have been specifically disclosed, itis understood that the invention is notlimited thereto as many variations will be` readily apparent to those skilledy in the art. and the invention is to be given its broadest possible interpretation within the terms oi'v the following claims:

I claim:

. 1. An electricV circuit controllinginstrumentality comprising a pair of` electric switches, a nrst movable means for operating one of said electric switches,y a second movablemeans for operating De-energization of coil B1 releases the other of said electric switches, an electromagnet, an armature normally spaced from said electro-magnet and movable toward and away from said electro-magnet, a movable contact, a stationary contact, a switching member mounting said movable contact normally spaced from said stationary contact, said switching member being operatively connected to, said armature. and movable therewith` to, perform aswitching operation, and actuatingmeans movable to actuate said iirst and second movable means t9 operate said pair of emetrie switches, said actuating means, in the same movement,v moving-said switching member to engage said movable coritact with said stationarycontact, and moving said amature into position to beheld magnetically by the electro-magnet.

2. In an electric circuit controlling instrumentality comprising a housing, a pair of electric switch means supported in said housing, a first pivoted lever means for operating one of said electric switch means, a second pivoted lever means for `operating the other of said electric switch means, an electro-magnet mounted in said housing, a movable armature normally spaced from said electro-magnet, a movable contact, a stationary contact, a switching member mounting said movable contact normally spaced from said stationary contact, a movable supporting member mounting said armature and said switching member for common movement, and a Vreciprocable actuating plunger `movable. to actuate said first and'second lever means to operate said pair of electric switches, said plunger, in this same movement, actuating said supporting member to move said switching member to engage said movable contact with said stationary contact and simultaneously move said armature into position to be held magnetically by the electro-magnet.

3. In an electric circuit controlling instrumentality comprising a housing, a pair of electric switch means supported in said housing, a first pivotally `mounted lever meansV for operating one of said electric switch means, a second pivotally mounted lever means for operating the other of said electric switch means, an electro-magnet mounted in said housing spaced from said pair of electric switch means, a movable armature normally spaced from saidl electro-magnet, a movable contact, a stationary contact, a switching member mounting said movable contact spaced `from said stationary contact, a pivoted supporting member mounting said armature and said switching member for common movement, and an axially movable actuating plunger, slidably supported by said housing, movable to actuate said iirst and second pivotally mounted lever means to operate said pair of electric switches, said actuating means, in this same movement, actuating said pivoted member to move said switching member to engage said movable contact with said stationary contact 'and at the same time to move said armature into position to be held magnetically bythe electro-magnet.

4. In an electric circuit controlling instrumentality comprising a housing, an actuating plunger slidably supported by said housing for endwise movement, a pair of electric switch means supported in said housing, pivotally mounted means for operating said pair of electric switch means, with the pivot axis of said means being disposed at one side of the plunger, anA electro-magnet mounted in, said housing spaced from said pair of electric switch means, a movable armature normally spaced from said electro-magnet, a switching member, a pivoted supporting means mounting said armature and said switching member for common movement, with the pivot axis of said pivoted supporting means being disposed on the opposite side of saidy plunger from said first mentioned pivot axis, means for moving said actuator plunger to actuate said first and second pivotally mounted lever means to operate said pair of electric switches, said actuating plunger, in vthis same movement, actuating said pivoted supporting means to move said switching mem- 13 ber to perform a switching operation and at the same time to move said armature into position to be held magnetically by the electro-magnet.

5. In an electric circuit controlling instrumentality comprising a housing, a pair of electric switch means supported in said housing, a rst pivotally mounted lever means for operating one of said electric switch means, a second pivotally mounted lever means for operating the other of said electric switch means, an electro-magnet mounted in said housing spaced from said pair of electric switch means, a pivotally mounted armature normally spaced from said electromagnet, a switching member operatively connected to said armature for movement therewith between circuit-making and circuit-breaking positions, an actuating plunger movably supported on said housing for endwise movement, a rst portion on said actuating plunger for engaging said pivotally mounted armature, on movement of said plunger, to move said armature into ,position closely adjacent said electro-magnet to be held magnetically thereby on energization of the electro-magnet, a second portion on said actuating plunger for engaging the rst pivotally mounted lever for movement thereof to operate its associated electric switch, and a third portion on said actuating plunger for engaging the second pivotally mounted lever means for moving it to operate its associated electric switch, said switching member moving, on movement of said armature, into circuit-making position. i

6. In an electric Acircuit controlling instrumentality comprising a housing, a reciprocable actuating plunger, a pair of electric switch means supported in said housing, a rst pivotally mounted lever means for operatingone of said electric switch means, with the pivot axis of said lever means disposed on one side of said plunger, a second pivotally mounted lever means for operating the other of said electric switch means, with the pivot axis of this latter lever means mounted on the same side of said plunger as is the pivot axis of the first lever means, an electromagnet mounted in said housing spaced from said pair of electric switch means, a movable armature normally spaced from said electromagnet, pivoted supporting means carrying said armature, the pivot axis of said supporting means being disposed on the opposite side of said plunger from said rst mentioned pivot axis, a switching member operatively connected to said armature for common movement therewith between circuit-making and circuit-breaking positions, a camming portion on said actuating plunger for engaging said pivoted armature supporting means, on movement of said plunger, to move said armature into position adjacent said electro-magnet to be held magnetically thereby on energization of the electro-magnet, a large diameter'portion on said actuating plunger for engaging the rst pivotally mounted lever means for movement thereof to operate its associated electric switch, and a small diameter portion on said actuating plunger for engaging said second pivotally mounted lever means for moving it to operate its associated electric switch, said switching member moving, on movement of said armature, into circuit-making position.

7. In an electric circuit controlling instrumentality comprising a housing, a longitudinally movable actuating plunger slidably mounted on said housing having an end movable within the interior of said housing, a pair of electric switch means supported in said housing, a first pivotally mounted lever means for operatingoneofsaid electric switch means, a roller rotatably supported by said lever means, a second pivotally mounted lever means for operating the other of said electric switch means, a roller rotatably supported by this second lever-means, an electromagnet mounted in said housing spaced from said pair of electric switch means, a movable armature normally spaced from said electromagnet, a switching member, a pivoted supporting means mounting saidV armature and said switching member for common movement, a roller mounted for rotation on said pivoted supporting means, a camming portion on said actuating plunger coacting with the roller on said pivoted armature supporting means to move said switching member into circuit-making position and to move said armature into position immediately adjacent said electro-magnet to be held magnetically thereby on energization of the electro-magnet, a large diameter portion coacting with the roller on the rst pivotally mounted lever means for movement thereof to operate its associated electric switch, and a small diameter portion on said actuating plunger for engaging said second pivotally mounted lever means for moving it to operate its associated electric switch.

8. In an electric circuit controlling instrumentality comprising a housing, an actuating plunger slidably supported by said housing for endwise movement therein and comprising a cam portion. a large diameter portion, a small diameter portion and a projecting portion extending from theend of the small diameter portion, a pair of electric switch -means supported in said housing, a rst pivotally mounted lever means for operating one of said electric switch means, with the pivot axis of said lever means disposed on one side of said plunger, a roller rotatably supported by said lever means and abutting said small diameter portion, a second pivotally mounted lever means for operating the other of said electric switch means, with the pivot axis of said second lever means mounted on the same side of said plunger as is the pivot axis of the rst lever means, a roller rotatably supported by said second lever means contiguous to said projecting portion on said plunger, an electromagnet mounted in said housing spaced from said pair of electric switch means, a movable armature normally spaced from said electromagnet, a switching member, a pivoted supporting member mounting said armature and said switching member for common movement, the pivot axis of said supporting means being disposed on the opposite side of said plunger from said rst mentioned pivot axes, a roller mounted for rotation on said pivoted supporting member and abutting said large diameter portion, and means for moving said actuating plunger in a rst direction to move said roller carried by said second lever means, into engagement with said small diameter portion thereby to move said second lever means to operate its associated electric switch, said movement of said actuating plunger causing said camming portion to coact with the roller on the pivoted armature supporting member to move the switching means to perform a switching operation and to move the armature into position immediately adjacent said electro-magnet to be held magnetically thereby on energization of the electro-magnet, this movement of actuating plunger in a rst direction also causing the large diameter portion of the plunger to coact with the roller on the rst pivotally mounted lever. means izomove -saidiirst lever means to operate its associated electric switch.

9; In an electric circuit controlling instrumentality comprising a housing, a longitudinally movable actuating plunger slidably mounted on Said housing having an end movable within the interior of said hcusing,a pair of electric switch means supported in said housing, a rst pivotally mounted lever means mounted adjacent said plunger, for operating one of said electric switch means, a roller rotatably supported by said lever means to be positioned abutting said plunger spaced from the interior end thereof, a second pivotally mounted lever means mounted adjacent said plunger and on the vsame side thereof as the rst lever means for operating the other of said electric switch means, a roller rotatably supported by this second lever means and abutting on said plunger closer to the end thereof than said roller on said first lever means, an electromagnet mounted in said housing spaced from said pair of electric switch means, a movable armature normally f spaced from said electromagnet, a switching member, a pivoted supporting means, positioned adjacent said plunger on the opposite side thereof than. said rst and second lever means, mounting said armature and said switching member for common movement, a roller mounted Vfor rotation on said pivoted supporting means and in abutment on said plunger farther from the end thereof than the other two rollers, a camu-ring portion on said actuating plunger coacting with the roller on said pivoted armature supporting means to move said switch-v ing member into circuit-making position and to move said armature into position immediately adjacent said electro-magnet to. be held magnetically thereby on energizatgion of the. electromagnet, alarge diameter portion coacting with the roller on the first pivotally mounted lever means for movement thereof to operate its associated electric switch, and a small diameter portion on said actuating plungerl for engaging said second pivotally mounted lever means for moving it to operate its associated electric switch.

l0. In an electricr circuit controlling instrumentality comprising a: housing, a pair of electric switch means supported in said housing, a first pivotally mounted lever means for operating one ating plunger for urging said plunger in a rst direction,` and movable means mounted upon the exterior of said housing for engagingand moving said actuating plunger in the opposite, direction and against the action of saidspring means to actuate said rst and second pivotally, mounted lever means to operate said pair of electric switches, said actuating plunger in this same movement, actuating said pivoted supporting member to move said switching member to perform a switching operation and simultaneously moving said armature closely7 adjacent said electro-.magnet in position to be held magnetically by the electro-magnet.

11.111 an electric circuit controlling instrumentality comprising a housing, a pair of electric switch means supported in saidl housing, a first lever means for operating one of said electric switch means, a second lever means for operating the other of said electric switch means, anelectro-magnet mounted in said housing, a movable armature normally spaced from said electromagnet, a switching member, a movable supporting member mounting said armature and said switching member for common movement, and a reciprocable elongated actuating plungerslidably supported by said housing and extending from the exterior thereof into operative position within said housing, spring means operatively connected to said plunger for urging it for movement outwardly of said housing, and a pivotal member mounted upon the exterior of said housing for engaging the exteriorly disposed end of the plunger to move said plunger inwardly and against the action of said spring means to actuate said first and second lever means to operate said pair 0fy electric switches, said plunger in this same movement, actuating said supporting member to move said switching member to perform a switching operation and simultaneously move said armature closely adjacent said electroof said electric switch means, `a second pivotally magnet inV position to be. held magnetically by the electro-magnet.

LAWRENCE J. BORDELON.

REFERENCES CITED The following references are of record in the iile of this patent:

lUNITED STATES PATENTS Number Name Date 800,098 McCarty June 10, 1884 1,731,39l Mottlau Oct. 15,1929 2,155,586. Ebert o Apr. 25, 1939 2,181,829 Jeffrey Nov. 28, 1939 2,266,784 Matteucci p Dec. 23, 1941 2,298,068 Pierce v Oct. 6, 1942 2,306,355 Gensburg g Dec. 22, 1942 2,372,102 Mahnke Mar. 20, 1945 2,468,974 Hammer May 3, 1949 2,503,632 Prather -i Apr,' 1,1, 1950

Images