US2565968A

US2565968A - Engine controller

Info

Publication number: US2565968A
Application number: US111448A
Authority: US
Inventors: Clarence H Jorgensen; William H Taylor
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1949-08-20
Filing date: 1949-08-20
Publication date: 1951-08-28
Anticipated expiration: 1968-08-28

Description

Aug. 28, 1951 c. H. JORGENSEN ET AL ENGINE CONTROLLER Original Filed Aug. 50

Patented Aug. 28,1951

ENGINE CONTROLLER Clarence. H. J orgensen, East Rochester, N. Y., and William H; Taylor, Anderson,jInd., assignors to General Motors Corporation, Detroit, Mich., a

corporation of Delaware Continuation of application Serial; No. 500,547,

August 30, 1.943. This 1949, Serial No..1 11,448

20 Claims. 1

This invention relates to the control of supercharged internal combustion engines for usein airplanes. In the copending application of John. Dolza et al., Serial No. 449,918, filed July 6, I942, and now abandoned, there'is disclosed an engine controller having a main control lever operated by the pilots throttle lever in the cockpit of the plane. By moving the lever, the throttle is partly opened and there is effected a. selection of the engine intake pressure to be maintained by the controller. As the altitude increases, a hydraulic servo-motor operates auto-- matically to increase the throttle opening so that the selected pressure will be maintained until critical altitude for the selected pressure is reached, the throttle then being widev open. The main control lever operates the propeller pitch control lever so that the governed speed of the engine is coordinated with the pressure selection thereby controlling the power output of the engine.

The mechanical operation of the propeller pitch control lever by the main control lever of the controller presents difficulties in certain installations, particularly where there is a substantial distance between the propeller governor and the engine near which the controller is located. In such installations, the transmission of mechanical motion between the control lever and the propeller governor adjusting lever is a serious problem. Therefore, it is an object of the present invention to provide for the movement of the governor adjusting lever by an electric servo-motor which can be located near the governor if desired and which is under the control of the main control lever of the throttle controller.

The operation of the. throttle by the controller of the Dolza et al. application depends upon the maintenance of a supply of oil under pressure and in preventing the oil from becoming too cold and viscous. Since the installation and maintenance of electric circuit is much simpler" andless expensive than in the case of hydraulic pipe lines, it is an object to provide for the automatic. actuation of the throttle valve by an electric servo-motor.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

The figure is a diagram of an embodiment of the present invention.

application August 20,

In the figure, an engine drives a propeller 2| having variable pitch blades adjusted by a governor 22 controlled by a lever 23. Engine 20 drives a shaft 24 operating a supercharger 25 having an outlet 2% controlled by a throttle valve 2? and leading to a carburetor 28 connected by manifold 29 with the engine intake ports.

The throttle 21 is adjusted by a controller 30 having an aneroid bellows 3! and a bellows 32 connected by pipe 33 with intake manifold 29 of the engine 20. A bar 34 connects the free ends of the bellows 3| and 32 and carries a pivot 35 for a lever 33 providing a plate 31 insulatinglv supporting

segments

38 and 39 spaced by a gap 99'. A spring 4| urges lever 36 against a datum or pressure selecting cam 42 connected with a shaft 33 operated by a main control lever 44.. The construction of the bellows is disclosed in detail in the copending application of John Dolza et al., Serial No. 449,918, filed July 6, 1942. The bellows contain springs of such calibration that the relation of movement of pivot 35 to changes inpressure in bellows 32 is substantially a linear relation.

Main control lever 44 is manually operated by the pilots throttle lever located in the cockpit of the airplane. The setting of lever 44 determines the position of the datum cam 42 and the manual setting of the throttle valve 21. As lever 46 is moved clockwise asindicated by arrow at, valve 2? is moved clockwise by virtue of a lever 45 connected with shaft 43, and by link 46' with a lever di' connected with a shaft 48, gear train 49' and 50 connecting shafts 48 and 5| and gear train 52 and 53 connecting shafts 5| and 54, the latter being connected with valve 21. An automatic movement of throttle valve 21 is effected by providing for orbital rotation of shaft 5i about the coincidental axes of shafts 48 and 54. Shaft 51 is supported by a

cage having arms

55 and 58 loosely journaled on shafts 68 and 54, respectively, and having a yoke 51 supporting a gear segment 58 meshing with a gear 59 fixed to a shaft 60 connected by speed reducing gearing 9! with the shaft 62 of reversible electric motor 63.

Motor 63 comprises an armature 64, a shunt field 65 and a series field 66. Both field's are connected with a wire 61, connected by a switch 68 with a battery 10. Armature 64 is connected by brushes ll and '12 with relay armatures l3- and "M, respectively, of relays l5 and 16, respectively, urged downwardly by springs 13a. and 14a, respectively. Armatures l3 and 74' carry contacts 71' and 18, respectively, normally in. engagement with contacts 79' and 80, respectively.

When relay magnet coils 8I or 812 are energized, armatures I3 and I4, respectively, move toward cores 83 and 84, respectively, to separate contacts IT or I8, respectively, from contacts I9 or 30, respectively, and to move contacts 11 or I8 into engagement with contacts 85 or 86, respectively. Wires 81 and 88 connect contacts 85 and 86, respectively, with a wire 89 connected with a wire 90 leading from battery I to shunt field 65. Contacts I9 and 80 are connected by wires SI and 92. respectively, with series field 66. Wire 89 is connected with relay coils 8| and 82. Relay coil 8| is connected by wire 93 with blade 94 of normally closed limit switch 95 connected by wire 96 with segment 38. Relay coil 82 is connected by wire 91 with limit switch 98 having a blade 99 connected by wire I33 with segment 39. Contact IIII resiliently biased toward the plate 31, is connected by wire I02 with wire 61.

. Limit switches 95 and 98 are normally closed, but when the valve 21 is in idle position, for example, the insulated end of an arm I35 engages blade 39 to open switch 98 thereby pre venting an operation of motor 53 which would tend to cause valve 21 to move further toward closed position. Likewise when valve 21 is wide open, arm I05 moves blade 94 down to open switch 35. Arm I05 is pivoted at I36 and is operated by a gear segment III'I meshing with a gear seg ment I58 connected with valve shaft 54.

When it is desired to ascend from ground level, lever 44 is moved clockwise to a position for selecting the manifold pressure required for take-off. Cam 42 rotates clockwise to allow spring M to move lever 36 counterclockwise to bring contact segment 38 into engagement with contact IllI. At the same time, this movement of lever 44 has caused valve 25 to be moved to an open position such that the manifold pressure becomes slightly less than the pressure selected for take-off and arm I65 moves away from blade 99 to permit switch 98 to close. The engagement of contacts 38 and I5I causes relay coil 8i to be connected with the battery Ill.

Armature I3 moves up to connect contacts I! and 85 while armature I4 remains down to connect contacts I8, 83 then the direction of current flow through armature 64 is such as to cause gear 59 to rotate counterclockwise and gear segment 58 and shaft 54 and valve 2? to U rotate clockwise toincrease the manifold pressure. Bellows 32 expands to cause pivot 35 to move left and the contact 38 to move left away from contact IIlI. When contact IfiI engages the gap or dead-spot 43, the motor 33 stops. Equilibrium is established when valve 2! has moved into such position that the manifold pressure is that selected by the setting of datum cam 42 As the plane ascends, the tendency is toward a deficiency in manifold pressure. Hence bellows 32 tends to contract to move contact 38 into engagement with contact IIlI. Therefore, the motor 63 operates in the manner described to move the valve 21 wider open in order-that the selected intake pressure will be maintained until the valve 21 is wide open. Then the limit switch 95 opens and the motor 63 is inoperative to effect a further clockwise movement of valve 21. The altitude at which the throttle 2! arrives at wide open position is the critical altitude for the pressure selected.

During descent, the tendency is toward an excess of intake pressure. The bellows 32 tends to expand to move pilot 35 left to bring contact 39 into engagement with contact IN. The relay coil 82 is connected with the battery It: to cause armature I4 to move up while armature I3 remains down. Contacts II, I9 and I8, 85 are connected. Then the direction of current flow through the armature 64 is such as to cause the motor. 63 to rotate gear 59 clockwise and the segment 58, the shafts 5| and 54 and the valve 21 counterclockwise to reduce the intake pressure to that which had been selected.

Therefore, between ground level and the critical altitude for a selected pressure, a selected intake pressure can be maintained. If a slight droop in selected pressure between ground level and critical altitude is desired, the external area of the aneroid bellows 3| can be made less than external area of the intake pressure responsive bellows 32.

In order that the engine output to the propeller may be controlled by the lever 44, the governed engine speed is caused to vary with the pressure selection according to a predetermined schedule. The coordination of pressure selection and governed speed adjustment is effected by a cam IG'I driven by the shaft 43 which may be made as long as desired to accommodate the distance between the engine valve controller 3|] and the propeller pitch changing lever 23.

The lever 23 is moved by a reversible electric motor IIG comprising an armature III, a shunt field H2 and a series field H3. Wire H4 connects these fields with wire 61. Armature III is connected by brushes I2l and I22 with armatures I23 and I24, respectively, urged downwardly by springs I23a and I24a, respectively, and being parts of relays I25 and I26, respectively. Armatures I23 and I24 carry contacts I21 and I28, respectively, normally engaging contacts I29 and I35, respectively, but movable into engagement with contacts I35 and I35, respectively, in response to the energization, respectively, of coils I3I and I32, surrounding cores I33 and I34, respectively. Wires I3! and I38 connect contacts I35 and I36, respectively, with a wire I39 connected with wire 90 and battery I9. Wire I connects shunt field H2 with Wire I39. Wire I4I connects contacts I29 and I30 with series field H3. Wires I and I46 connect relay coils I31 and I32, respectively, with limit-switch brushes I41 and I48, respectively, engaging segment contacts I49 and I 53, respectively, carried by a non-conducting disc I5I driven by a shaft I52 connected by friction clutch discs I53 (urged into contact by a spring I53a) with a shaft I54 connected by speed reducing gearing I55 with motor shaft [56. Contacts I49 and I50 are engaged by brushes I51 and I58, respectively, connected by wires I59 and I60 respectively, with contact segments I6I and IE2 insulatingly supported by a plate I63 with a gap or dead spot between them. Plate IE3 is fixed to a shaft I64 fixed to an arm I55 carrying a roller E55 urged by spring I65a against the control cam I6! which is shaped so as to meet a predetermined schedule between pressure selections and governed engine speeds. Segments IBI and I62 are engaged selectively by a contact I'IIl carried by a disc III insulatingly supported by shaft I52 and driven thereby and engaged by a brush In connected with wire H4.

Shaft I52 is connected by arm I'I3, link I 75, bellcrank I15 (pivoted at I16) and link III with governed speed adjusting lever 23.

If cam I6! moves the plate I63 clockwise to bring contact IBI into engagement with contact I10, relay coil I SI is energizedand relay armature !23 moves up while relay armature I24 remains down. Motor I I 0 causes shaft IBZ-torotate clockwise until contact I moves to the dead-spot between the segments I6I, I62. During this movement of shaft I52, the lever 23 moves counterclockwise to a position which willproduce a governed speed corresponding to the pressure-speed schedule. If cam It! moves the plate I63 counterclockwise to bring contact I62 into engagement with contact I1I, relay coil [.32 is energized and relay armature I 24 moves up while relay'armature I23 moves down. Then-motor IIB causes shaft I52 to rotate counterclockwise until contact Ill) moves 'to the .dead-espot between the segments I6I, I62. During this movement of the shaft I52, the lever 23 moves clockwise to a position which will produce a governed speed .according to the pressure-speedschedule.

The main control lever 44 fixes the positions of the pressure-selecting cam 42 and the plate I83 according to the pressure-speed schedule. Motor 63 is under the control of cam 42 to maintain a selected pressure. Motor H0 is under the control of plate I63 to cause contact I Ill to follow to the dead spot between contacts It! and I62 in order to locate the speed adjusting lever in the required .position to give the speed which matches the pressure selection.

This application is a continuation of application Serial No. 500,547, filedAugust 30, .1943, and now forfeited.

While the embodimentof the presentfinvention as herein disclosed, constitutes apreferred form, it is to be understood that other forms 'might'be adopted, all coming within the scopeof the claims which follow.

What is claimed is as follows:

1. Apparatus for regulating the pressure in the intake conduit of a supercharged internal :combustion engine having a throttle-valve movable to different positions to'variably control the emgine intake pressure, a pressure selecting device movable to select different intake-pressures'manually operable means for actuatingsaid device to select some desired pressure and effective to open the throttle valve sufficiently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, means responsive to .the engine intake pressure, and means under control of the manually operable means and the pressure responsive means for controlling the operation of said electric motor.

2. Apparatus for regulating the pressure in the intake conduit of a supercharged .internal combustion engine having a throttle valve movable to different positions to variably control'the engine intake pressure, a pressure-selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve suiflciently to obtain a pressure approaching that selected .but always ineffective to move the valve enough to obtain the selected pressure,'a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected and for-effecting. such other movements of the throttle as are :necessar to maintain the selected pressure during operation of the aircraft at different altitudes, means responsive to the engine intake pressure, andmeans under control of the manually operable means and the pressure responsive means for controlling the operation of said electric motor.

3. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the en gine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufficiently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, said movements of the valve by the manually operable means and the motor being independent of each other, means responsive to the engine intake pressure, and means under control of the manually operable means and the pressure responsive means for controlling the operation of said electric motor.

4. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufficiently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected and for effecting such other movements of the throttle as are necessary to maintain the selected pressure during operation of the aircraft at different altitudes, said movements of the throttle valve by the manually operable means and the motor being independent of each other, means responsive t the engine intake pressure, and means under control of the manually operable means and the pressure responsive means for controlling the operation of said electric motor.

5. Apparatus for regulating the pressure in-the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said de vice to select some desired pressure and effective to open the throttle valve sufficiently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain theselected pressure, a reversible electric motor for effecting .such additional movement of the throttle valve as is ncessary to obtain whatever pressure is selected and means operable by the manually operable means for causing the motor to become operative to effect said additional movement of the throttle valve.

6. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable .to different positions to variably control the-engine intake pressure, a pressure selectingdevioe movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufiiciently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, means responsive to the engine intake pressure, means operable by the manually operable means for causing the motor to become operative to effect said additional movement of the throttle valve and means operable by the pressure responsive means to cause said motor to become inoperative when the throttle valve has been moved to the proper position to obtain the selected pressure.

7. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufliciently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, means responsive to the engine intake pressure, circuits for controlling the operation of said motor, a control switch for controlling said circuits, means operable by the manually operable means to close said switch and cause the motor to become operative to effect said additional movement of the throttle valve,

and means operable by the pressure responsive means to open said control switch and render the motor inoperative when said additional movement of the throttle has been completed.

8. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve suniciently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, and for effecting such other movements of the throttle as are necessary to maintain the selected pressure during operation of the aircraft at different altitudes, means responsive to engine intake pressure, circuits for controlling the operation of said motor, a control switch for controlling said circuits, means operable by the manually operable means to close said switch and cause the motor to become operative to effect said additional movement of the throttle valve, means operable by the pressure responsive means to open said control switch and render the motor inoperative when said additional movement of the throttle has been completed and the selected pressure obtained, said pressure responsive means being also operative to close the control switch upon operation of the aircraft at different altitudes in order to maintain the selected pressure during such operation.

9. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufficiently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, circuits operable respectively for effecting operation of the motor in opposite directions to open and close the throttle valve, and means operable by the manually operable means when a pressure is selected to close the circuit causing operation of the motor in a direction to open the throttle and effect the additional opening movement thereof necessary to obtain the selected pressure.

10. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufiiciently to obtain a pressure approaching that selected but always inefiective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, circuits operable respectively for effecting operation of the motor in opposite directions to open and close the throttle valve, means operable by the manually operable means when a pressure is selected to close the circuit causing operation of the motor in a direction to open the thIOtblB and effect the additional opening movement thereof necessary to obtain the selected pressure, means responsive to the engine intake pressure and means operable by said pressure responsive means for opening said last named circuit when the throttle has been opened sufficiently to obtain the selected pressure.

11. Apparatus for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttle valve movable to different positions to variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve sufilciently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, means responsive to the engine intake pressure, circuits operable respectively for effecting operation of said motor in opposite directions to open and close the throttle valve and means under control of the manually operable means and said pressure responsive means for controlling said circuits so as to determine the direction of operation of said motor and the extent of movement of the throttle valve by said moton 12;. Apparatus. for regulating the pressure in the intake conduit. of a. supercharged'internal combustion. engine having a. throttle valve movable to. different positions to. variably control the engine intake pressure, a pressureselecting device movable to select difierent intake pressures, manually operable means. for actuating said device to select some desired pressure and effective to .open the throttle valve sufficiently to obtain a pressure. approaching: that; selected but always ineffective to move the valve enough to obtain the selected pressure, a reversible electric motor for eifectingsuch additional movement. of the throttle.- valve as isv necessary to obtain whatever .pressure. is selected, means. responsive to the enthe other of the fixed contacts to determine the direction of operation of the motor andextent of movement of the throttle: valve.

13;..Apparat-us for regulating the pressure in the intake conduit of a supercharged internal combustion engine having a throttlevalve movable to different positions to variablycontrol the engine intake pressure, a pressure selecting device movable to select diflerentintake pressures,

manually operable means for actuating said device to. selectsome desired pressure and eifective to. open the throttle valve sufficiently to obtain a pressure approaching that selected but always ineffective to move-the valve enough to obtain the selected pressure, a reversible electric motor for efiecting such additional movement oi the throttle valve as is necessary to obtain whatever pressure is selected; means responsive to the engine intake pressure, circuits operable respectively for eifeoting operation of the motor in opposite directions to open. and close the throttle, a two-way switch controlling said circuits comprising .a member carrying spaced contacts. and a contact member engageable with either one of said spaced contacts, a current source connected with said contact member, relays connected, re,- spectively with each of thespaced contacts. and adapted to render one-or the other of the'motor circuits operative, and'means under control of the manually operable means and the pressure responsive means for moving one of the switch members relative to the other in order to energize one or the other of said relays.

14. Apparatus for regulating the pressure in the intake conduit of a supercharged. internal combustion engine having a throttle valve movable to diiferent positions to variably control the engine intake pressure, a pressure selecting device movable to select diiTerent intake pressures,

manually operable means for actuating said device to select some desired pressure and effective to open the throttle valve suuiiciently to obtain a pressure approaching that selected but always ineffective to move the valve enough to obtain the selected pressure, a reverisble electric motor for effecting such additional movement of the throttle valve as is necessary to obtain whatever pressure is selected, means responsive to the engine intake pressure, circuits operable respectively for effecting operation of the motor in opposite directionsto open and close the throttle, a two-way switch controlling said circuits comprising a member carryingspaced contacts and a contact member engageable-with eitherone of said spaced contacts, a current source connected with said contact member, relays connected respectively with each of the spaced contacts and adapted to render one or the other of the motor circuits operative, and meansunder control of the manually operable means and the pressure responsive means for moving the switch member carrying said spaced contacts relative to the other contact member So as to efiect-engagement of the latter with one or'the other of said spaced contacts in order to energize one orthe other of said relays.

15. Apparatus for regulating the pressure in the intake conduit ofa supercharged internal combustion engine having a throttle valve movable to diflerent positionsto variably control the engine intake pressure, a pressure selecting device movable to select different intake pressures, manually operable means for actuating said device to select some desired pressuregand effective to; open the throttle valve sufiiciently to obtain a pressure approaching that selected but always ineffective to move the valve enough'to obtain the selected pressure, a reverisble electric motor for effecting such'additional movement of the throttle valve as, is necessary to obtain whatever pressure is selected, means responsive to the en gine intake pressure, circuits operable respectively for effecting operation of: the motor in opposite directions to open and close the throttle, a two-way switch controlling said circuits comprising va member carrying spaced contacts and a contact member engageable with either of said spaced contacts, means operable by the manually operable means for effecting engagement of the contact member with one orthe. otherof said spaced contacts when apressure is selected, means operable by the pressure responsive means for disengageing said contacts when the motor has moved the throttle valve sufiiciently to obtain the pressure selected, said last named means being also operable by the pressure responsive means to effect engagement or the contact memher with one or the other of said spaced contacts when the intake pressure varies from that seleoted.

. 1 n engi e. throttle va ve controller for us w th. a. upercharged airplane ng ne comprising the com nat on with. the throttlev valve, of a main control lever, a reversible electric motor, a mechanism including aligned shafts connected, respectively, with the lever and valve and gearing connecting the shafts including a counter-shaft and connected gears thereon and gears attached, respectively, to the aligned shafts and meshing, respectively, with the gears on the counter-shaft whereby motion is transmitted from the lever to the valve, said mechanism including a frame supporting the counter-shaft for rotation about the aligned shafts and means operated by the motor for rotating the frame whereby motion is transmitted to the valve from the motor, an element responsive to engine intake pressure and means for controlling the operation of the motor, said means being under the control of the lever and the intake-pressure-responsive element.

17. An engine throttle valve controller for use with a supercharged airplane engine comprising the combination with the throttle valve, of a main control lever, a reversible electric motor, means for transmitting motion from the lever to the valve independently of the motor, means for transmitting motion from the motor to the valve independently of the lever, an element responsive to engine intake pressure, circuits operable respectively for efiecting operation of the motor in opposite directions, a two-way switch comprising a member and spaced contacts insulatingly supported thereon and a contact member engageable with either of the contacts of the first member or with neither, a current source connected with the second member, relays connected respectively with the contacts on the first member, and operable respectively to render operative the motor control circuits, a datum or pressure-selecting cam operated by the main control lever, and a second lever positioned by the datum cam and by the intake-pressure-responsive element for moving one of the two-way switch members relative to the other switch member.

18. An engine throttle valve controller for use with a supercharged airplane engine comprising the combination with the throttle valve, of a main control lever, a reversible electric motor, means for transmitting motion from the lever to the valve independently of the motor, means for transmitting motion from the motor to the valve independently of the lever, an element responsive to engine intake pressure, circuits operable respectively for effecting operation of the motor in opposite directions, a two-way switch comprising a member and spaced contacts insulatingly supported thereon and a contact member engageable with either of the contacts of the first member or with neither, a current source connected with the second member, relays connected respectively with the contacts on the first member and operable respectively to render operative the motor control circuits, a datum or pressureselecting cam operated by the main control lever, and a second lever having a floating fulcrum positioned by the intake-pressure-responsive element and having an arm engaging the datum cam, said second lever effecting the movement of one of the two-way switch members relative to the other switch member.

19. An engine throttle valve controller for use with a supercharged airplane engine comprising the combination with the throttle valve, of a main control lever, a reversible electric motor, means for transmitting motion from the lever to the valve, independently of the motor, means for transmitting motion from the motor to the valve independently of the lever, an element responsive to engine intake pressure, circuit operable respectively for effecting operation of the motor in opposite directions, a two-way switch comprising a member and spaced contacts insulatingly supported thereon and a contact member engageable with either of the contacts of the first member or with neither, a current source connected with the second member, relays connected respectively with the contacts on the first member and operable respectively to render operative the motor control circuits, a datum or pressure-selecting cam operated by the main control lever, and a second lever having a floating fulcrum positioned by the intake-pressure-responsive element and having an arm engaging the datum cam, said second lever providing the first mentioned member of the two-way switch.

20. An engine throttle valve controller for use with a supercharged airplane engine comprising the combination with the throttle valve, of a main control lever, a reversible electric motor, means for transmitting motion from the lever to the valve independently of the motor, means for transmitting motion from the motor to the valve independently of the lever, aligned bellows having remote ends fixed and adjacent ends connected by a bridge, one of the bellows being evacuated and the other being connected with the engine intake, circuits operable respectively for effecting operation of the motor in opposite directions, a datum or pressure-selecting cam operated by the main control lever, a second lever positioned by the cam and pivotally supported by the bellows bridge whereby the second lever is controlled by the main control lever and by engine intake-pressure, a two-way switch comprising spaced contacts insulatingly supported by the second lever and a third contact engageable with either of the contacts supported by the second lever or with neither, a current source connected with the third contact, and relays connected respectively with the contacts supported by the second lever and operable respectively to render operative the motor control circuits.

CLARENCE H. JORGENSEN. WILLIAM H. TAYLOR.

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

Mock Nov. 9, 1948