US2154303A - Power system - Google Patents

Description

April 11, 1939. LA MAR-s COPER 2,154,303

POWER SYSTEM Filed 0G12. 30, 1937 2 Sheets-Sheet l His Att cbr-neg.

April 11, 1939. LA MAR s. COOPER 2,154,303

POWER SYSTEM Filed oct. so, 1957 2 sheets-sheet 2 I lha Inventof: La Mar' .5. C ooper-,

His Attorney.

UNITED STATES PATENT OFFICE POWER SYSTEM La Mar S. Cooper, Erie, Pa., assignor to General Electric Company, a corporation of New York Application October 30, 1937, Serial No. 171,981

12 Claims.

My invention relates to power systems, and arrangements for controlling the operation thereof.

An object of my invention is to provide a power system having a prime mover with an arrangement for governing the speed thereof including a device responsive to predetermined loads on the system for varying the governed speed controlled by the governing arrangement.

Another object of my invention is to provide a power system having a prime mover with an improved arrangement dependent upon the load on the system for controlling the speed of response of a prime mover speed governing device.

Further objects and advantages of my invention will become apparent and my invention will be better understood from the following description referring to the accompanying drawings, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

For a better understanding of my invention, reference is made to the accompanying drawings, wherein Fig. l is a side elevation of a power unit embodying my invention and illustrating the arrangement of the prime mover and an electric generator driven thereby, the details being omitted; Fig. 2 is an enlarged side elevation of the prime mover shown in Fig. 1 illustrating the arrangement of my improved speed governing device the fan being omitted; Fig. 3 is an end view of the power unit shown in Fig. 2; Fig. 4 is a perspective view showing the lost-motion connection between the pivoted governor loading levers; Fig. 5 is a sectional view taken along 5 5 of Fig. 3 of the governor loading control valve; Fig. 6 is a partial sectional view taken along line 6 6 of Fig. 2 of the electromagnetic governor loading control valve; Fig. 7 is a partial sectional view taken valong line 'I-1 of Fig. 3 of the centrifugal governor; and Fig. 8 is a schematic diagram of the electrical power system.

Referring to the drawings, I have shown a power system including an internal combustion engine I0 or other suitable prime mover arranged to drive a generator or dyn-amo-electric machine I I having a stationary member I2 rigidly secured to an engine block I3. The engine is provided with a cooling arrangement including a water circulating system provided with any suitable radiator which may be connected to an engine water jacket connection I4 and through this connection to a water pump I5, which is driven by a pulley I6 through a fan belt I'I driven by a pulley I8 connected to the engine crank shaft. A

fan I9 is driven by and mounted on the pulley I6 to assist in cooling the circulating water.

In order to control the power developed by the engine and the speed of the power unit at various loads, a governing arrangement is provided for controlling the fuel supplied to the engine by a carburetor through an intake manifold 2| according to predetermined load and speed conditions of the power unit. The fuel supply is controlled by any suitable throttle valve arranged within a valve chamber 22 Vand the valve is operated by a throttle control link 23 connected to the throttle valve lever through a ball and socket joint 24. 'I'he throttle link 23 is operated by a long arm 25 of a throttle operating lever to which it is pivotally connected in an opening 26 formed in the end of the lever. The throttle operating lever arm 25 is pivotally supported by a pivot pin 21 secured to a boss 28 formed on the intake manifold 2 I. In order to provide for the manual throttling of the engine, a throttle wire 29 extends to a suitable panel board and is guided through ar sheath 30 secured by a clamp 3| to the intake manifold. The end of the throttle Wire 29 is secured by a clamp 32 to a manual throttle control lever 33, which also is pivotally secured by the pivot pin 21 to the intake manifold. A dog or projection 34 is formed on the manual throttle lever 33 and is arrangedl so that when the throttle wire 29 is moved to close the throttle, which is toward the right as seen in Fig. 2, the manual throttle lever 33 turns in a clockwise direction and the dog 34 engages the upper edge of the long arm 25 of the throttle operating lever and turns it in a clockwise direction. This movement tends to close the engine throttle against the tension of a throttle lever spring 35 secured at one end to an ear 36 formed on the upper edge of the long arm 25 of the throttle operating lever and arranged to bias the throttle operating lever to an open throttle position. The throttle wire 29 is made sufliciently stili to enable it to pivot the manual throttle lever 33 against the tension of this throttle lever spring 35, and there is no provision for pulling open the throttle manually by the manual throttle lever 33, as there is no connection between the throttle' operating lever and the manual throttle lever for transmitting counterclockwise motion, as viewed in Fig. 2, from the manual lever to the throttle operating lever. Thus, the throttle may be manually closed by positive action and permitted to open under the action of the spring 35 by varying the position of the manual throttle lever 33, which is retained in adjusted position by friction of the operating connections.

In certain power systems, the loads often vary within relatively narrow predetermined ranges, and it is desirable that the prime mover should be governed in accordance with these predetermined load conditions in order to provide the most satisfactory and eflicient operation thereof. In the power system illustrated in the drawings, the engine l0 is arranged to drive the electric generator Il, which is adapted to supply electrical power to anti-aircraft apparatus. This apparatus includes a searchlight 31, which may be connected in circuit with the generator by closing a switch 38, and position locating a phonic apparatus 39, also connected to the generator by leads 40. These loads may be connected either singly or together to the generator and it is desirable that the engine should be governed to provide predetermined operating speeds for the different load conditions. In order to provide this governed operation, I provide a governing device for the engine I8, which includes a governor throttle lever 4| pivotally secured to the intake manifold 2| by the pivot pin 21 and to an upwardly extending arm 42 of a governor lever by a throttle connecting rod 43. The governor throttle lever 4| is provided with an outwardly extending dog or projection 44, which is arranged to engage the under edge of a short arm 45 of the throttle operating lever to govern the opening of the throttle when the manual throttle lever 33 is moved in a counterclockwise direction, as viewed in Fig. 2, out of engagement with the long arm 25 of the throttle operating lever. Thus, the position of the governor throttle lever 4| determines the maximum opening of the throttle under any conditions when the manual throttle lever 33 is not used to limit the opening thereof. In order to provide for the opening of the throttle in response to movement of the governor throttle lever 4|, the throttle biasing spring 35 extends from the ear 36 on the throttle operating lever arm 25 to a finger 46 secured to the upper end of the governor throttle lever 4| adjacent its connection to the throttle connecting rod 43. The throttle is adapted to be governed by a centrifugal governor through the governor lever arm 42 during normal operation, and Fig. '7 is an enlarged sectional view of the centrifugal governor mechanism. The centrifugal governor is driven by the fan belt |1 through a governor pulley 41 which is keyed to a governor shaft 48 and is secured thereto by a nut 49 threadedly engaging the end of the governor shaft. The governor shaft is supported at one end by a sleeve bearing 50 mounted in a hub 5| in the end of a governor casing 52, attached to the engine, and at the other end by ball bearings 53 mounted in an end shield 54 secured by screws 55 to the casing 52. Centrifugal governor weights 56 are pivotally secured by pivot pins 51 to ears 58 formed on a collar 59, which is secured to the governor shaft 48 by a rivet 60. The governor weights 56 are provided with inwardly extending fingers 6| arranged in engagement with the outer face of an annular flange 62 formed on an end of an axially movable sleeve 63. A bearing ring 64 is arranged over the other end of the sleeve 63 and is carried in a relatively rotatable relation thereto in engagement with ball bearings 65, which are supported on a shoulder 66 and against a flange 61 formed on the sleeve 63. This rotatable ring 64 is movable axially with the sleeve 63 and is arranged to engage a pair of fingers 68 arranged one on each side of the governor shaft. The fingers 68 are part of a yoke 63 extending from a hub 1|) thereon, which is secured by a pin 1| to a governor lever shaft 12 rotatably supported on the governor casing by sleeve bearings. The governor lever 42 is rigidly secured by a pin 42a to the governor lever shaft 12 and is arranged to pivot therewith, when the lingers 68 are moved axially by the axial movement of the sleeve 63 in response to the pivoting of the centrifugal governor weights 56 about the pins 51 under the action of centrifugal force. The entire mechanism within the governor casing 52 is lubricated by lubricating oil fed thereto under pressure from the forced feed engine lubricating system through a pipe 13 connected to a boss 14 formed in the top of the governor casing 52 and returned to a crank case 15 of the engine Hl by a tube 16 connected to a boss 11 formed on the bottom of the governor casing 52. In order to insure the return of the centrifugal weights 56 toward the governor shaft 41 as the speed of rotation diminishes, and to obtain a uniform governing action, these weights 58 are biased inwardly by a pair of loading springs 18 and 19 connected to pins and 8| in openings formed in the end of a lower arm 84 of the governor lever 42 and secured by nu.s 82 and 83, respectively. The tension of these loading springs 18 and 18 may be adjusted by varying the position of the nuts 82 and 83 on the pins 80 and 8|, respectively, and the other end of each of these loading springs is connected to a pivoted loading lever 85 and biases the lower governor lever arm 84 toward the pivoted loading lever 85. This loading lever is pivotally secured by a pivot pin 86 to the governor l casing 52 at one end, and the loading spring 18 is secured to an ear 81 formed thereon adjacent the pivot pin 86, so that movement of the loading lever has substantially no effect upon the tension of the spring, while the other loading spring 19 is secured to the lower end thereof adjacent a stop 88, which also is pivotally secured thereto by a pivot pin 89. The other end of this stop is formed with a cylindrical portion 9U of reduced section, which extends through an opening 9| in the lower end of the lower governor lever arm 84, so as to guide the stop and maintain it in correct relation with respect to the governor lever. A shoulder 92 is formed at the inner end of this cylindrical portion 90, and provides initial tension in the spring 19.

The power system illustrated in the drawings has two principal operating speed ranges corresponding to two general load conditions. 'I'he searchlight 31 forms the main electrical load on the system and requires a higher operating range of speed of the generator and engine than is required by the auxiliary load provided by the phonic apparatus 39, and these speed ranges may be termed the main load and the listening load speeds of the power unit. It is desirable that the governor should be able to govern the speed of the engine for different speed ranges in accordance with the load on the system, and this may be obtained by applying different loadings to the centrifugal governor weights under the diierent load conditions. In order to vary the governor loading, I provide a diaphragm cylinder arranged to control the loading of the governor by the loading springs 18 and 19, and adapted to be operated in response to the load on the engine by the fuel intake pressure in the engine intake manifold 2|, and controlled by an electromagnetic valve responsive to the electrical load on the system. This diaphragm cylinder is illustratif i) ed in detail in Fig. 5 and comprises a pair of complementary cup-shaped cylindrical elements 93 and 94 within which is arranged a flexible diaphragm 95 secured in position by bolts 96 which also secure together the two cylindrical elements 33 and 94. A resilient coil spring 91 is arranged Within the cylinder on one side of the diaphragm 95 and biases it toward the other side of the cylinder. The center of the diaphragm 95 is secured to a diaphragm connecting rod 98, which extends loosely through an opening 99 in a bushing secured to the diaphragm cylinder element 93 by threaded engagement with a nut |0| arranged on the interior of the cylinder. A flexible gland |02 is secured to the outer end of the diaphragm connecting rod 98, and to the bushing |00 between annular iianges |03 and |04 formed on the bushing in order to exclude foreign matter from the interior of the diaphragm cylinder. The loose fit of the connecting rod in the opening 99 in the bushing permits the passage of air from the space within the sealing gland |02 to the space between the diaphragm 95 and the cylinder element 93 when the diaphragm 95 is moved away from the cylinder element 93 toward the cylinder element 94, air being permitted to flow into and out of the gland |02 through an opening |02a. 'I'he bushing |00 also is arranged to extend through an opening in a supporting bracket and secures the diaphragm cylinder in position thereon by clamping the bracket |05 between the bushing flange. |04 and nut |0|. The outer end of the diaphragm connecting rod 98 is secured by threaded engagement with a yoke |06, and is pivotally secured by a pivot pin |01 extending through openings |08 in the yoke |06 to the lower end of a second pivoted loading lever |09, which is pivotally secured to the governor casing 52 by the pivot pin 86. The pivoted end of the loading lever |09 is provided with a pair of axially projecting and diametrically extending dogs ||0 arranged within slots and ||2 formed in a hub 3 on the other pivoted loading lever 85. As shown in Fig. 4, the slots and ||2 are formed wider than the dogs ||0 to provide a predetermined limited amount of relative free pivotal lost-motion in the connection formed by the engagement of the dogs and the sides of the slots.

When the system is operating with only the listening load, the electromagnetic valve is operated by an exciting coil ||4 energized by an electric battery ||5 through a manually operable noload switch ||6 and a pair of contacts ||1 and contacter ||8 of a main load relay ||9. Under f. this condition, the electromagnetic valve, shown in detail in Fig. 6, is energized and an armature |20 is magnetically pulled downwardly against a valve stem |2| against the pressure of a resilient coil spring |22. This establishes a pneumatic connection from the spring side 94 of the diaphragm cylinder through a tube |23 connected between an opening |24 in the diaphragm cylinder to a valve manifold |25, and through a manifold opening |26, a valve casing opening |21, to a valve chamber |28, through an opening between a lower valve seat |29 and a lower valve face |30, through a valve casing opening |3|, a manifold opening |32, to a tube |33, a spring pressed check valve |34, a tube |35, and to the engineintake manifold 2|. The spring pressed-check valve |34 opens as indicated by the arrow |34a, toward the connection to the intake manifold 2|, and closes toward the connection to the magnet valve casing |25. Thus, under listening load conditions, the diaphragm 95 is subjected to the differential pressure between the engine intake manifold pressure and atmospheric pressure, as the spring side of the diaphragm is affected by engine intake manifold pressure, and varies with the minimum manifold intake pressure, because the check valve |34 prevents rapid fluctuation of the intake manifold pressure producing corresponding rapid fluctuations of the diaphragm 95. The atmospheric pressure on the connecting rod side of the diaphragm tends to move the diaphragm 95 toward the diaphragm cylinder element 94 against the pressure of the spring 91. This tends to pivot the pivoted loading lever |09 in a clockwise direction, as viewed in Fig. 2 and moves the dogs ||0 out of engagement with sides |36 and |31 of the slots and ||2 respectively, ofthe other loading lever 85, which limits the maximum throttle opening position, and permits the pivoted loading lever 85 to move with the lower governor 1ever arm 84 in response to actuation thereof by the centrifugal governor weights 56. In this manner, only the loading spring 18 is effective in loading the governor, as the loading spring 19 merely retains the pivoted loading lever 85 biased towards the lower governor lever arm 84, and does not resist the motion thereof within the limits of the lost motion in the connection between the dogs ||0 and the slots and ||2. Thus, the loading of the centrifugal governor weights 56 is dependent only on the loading spring 18 for controlling the throttle operation at listening load speeds, and the centrifugal governor weights will tend to operate the governor lever 42 to maintain the governor throttle lever 4| at a throttle opening position corresponding to a lower engine speed range than if both the loading springs 18 and 19 were effective for resisting the action of the governor weights.

When operating under main load conditions, it is desirable that the governor lever 42 should be permitted to open fully the throttle if the load on the system requires full throttle; that is, the shoulder 92 of the stop 88 on the pivoted loading lever 85 should be moved to a full throttle position, so as to be disengaged from the lower governor lever arm 84 except in the extremev open throttle position thereof. Furthermore, the lower governor lever arm 84 should be loaded by both loading springs 18 and 19 and biased thereby toward the pivoted loading lever 85 to provide a predetermined main load resistance to the actuation of the governor weights 56 greater than the loading resistance for the listening load position. This is obtained when the pivoted loading lever 85 is held in its extreme counterclockwise position, as viewed in Fig. 2, by the dogs ||0 of the loading lever |09 when the diaphragm 95 is in is spring extended position, as shown in Figs. 2 and 5. Under these conditions, the main searchlight load circuit is closed through the switch 38 and energizes a relay exciting coil |38 of the relay I9. This causes the contacter ||8 of the relay ||9 to open the circuit between the contacts ||1, thereby opening the circuit of the exciting coil ||4 of the electromagnetic valve. When the electromagnetic valve exciting coil ||4 is thus deenergized, the biasing spring |22 raises the lower valve face |30 into contact with the lower valve seat |29 and closes the connection between the engine intake manifold 2| and the spring side of the diaphragm 95 and opens the upper opening between an upper valve seat |39 and an upper valve face |40, thereby providing a connection between the spring side of the diaphragm 95 through the tube |23, the upper valve manifold opening |26, the

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upper valve chamber I4I, and through a tube |42 to an air lter |43, which communicates with the atmosphere. This provides an atmospheric vent from the spring side of the pressure differential diaphragm 95 under main load conditions, and permits the biasing spring 91 to extend the diaphragm 95 toward the diaphragm connecting rod side 93 of the diaphragm cylinder. This position of the diaphragm 95 and the diaphragm connecting rod S8 pivots the loading lever |09 in a counterclockwise direction and the dogs H into engagement With the sides |36 and |37 of the slots and ||2, respectively, of the loading lever 85 and carries the shoulder 92 of the stop 8B out of engagement with the lower governor lever arm 84, except in the extreme open throttle position. The leading spring 19 biases the pivoted loading lever 85 in a clockwise direction, as viewed in Fig. 2, and prevents lost motion between the two loading levers S and |09, so that any movement of the centrifugal governor Weights 56 is resisted by both the loading springs '18 and 19, and the lower governor lever arm opening 9| engages the cylindrical portion 80 of the stop 88 without producing any resistance to relative motion therebetween. In this manner, the speed of response of the engine governor is varied by the loading arrangement in response to the engine load and depends upon the electrical load on the power system for controlling the operation of the loading arrangement.

While I have illustrated and described a particular embodiment of my invention, modifications thereoi will occur to those skilled in the art. I desire it to be understood, therefore, that my invention is not to be limited to the particular arrangement disclosed, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States, is:

l. An electrical power system including a prime mover, speed responsive means for governing the speed of said prime mover, means dependent upon the load on said prime mover for varying the response of said governing means by varying the loading thereof, and electroresponsive means dependent upon the electrical load on said power system for controlling said response varying means.

2. A power system including a prime mover, an electric generator driven by said prime mover, means for governing the speed of said prime mover, an electrical load, means for connecting said electrical load in circuit with said generator, means for varying the response of said governing means by varying the loading thereof, and means dependent upon the load on said generator for controlling said response varying means.

3. A power system including a prime mover, an electric generator driven by said prime mover, means for governing the speed of said prime mover, an electrical load, means for connecting said electrical load in circuit with said generator, and means responsive to the load upon said generator and dependent upon the load of said prime mover for varying the response of said governing means by varying the loading thereof.

4. A power system including an internal cornbustion engine prime mover, a generator driven by said engine, means for governing the speed of said engine, an electrical load, means for connecting said electrical load in circuit with said generator, and means dependent upon the fuel intake pressure of said engine for varying the response of said governing means by varying the loading thereof.

5. A power system including an electric generator, a main electrical load, means for connecting said main electrical load in circuit with said generator, an auxiliary electrical load, means for connecting said auxiliary electrical load in circuit with said generator, means for governing the speed of said generator, and means dependent upon the connection of said main electrical load to said generator for controlling the response of said speed governing means by varying the loading thereof.

6. A power system including an internal combustion engine, a generator driven by said engine, means for governing the speed of said engine, an electrical load, means for connecting said electrical load in circuit with said generator, means dependent upon the fuel intake pressure of said engine for varying the response of said governing means by varying the loading thereof, and means dependent upon the load on said generator for controlling said response varying means.

7. A power system including a prime mover, a generator driven by said prime mover, means for governing the speed of said prime mover, a main electrical load, means for connecting said main electrical load in circuit with said generator, an auxiliar;- electrical load, means for connecting said auxiliary electrical load in circuit with Said generator, and means dependent upon the load on Said generator for varying the governed speed of said governing means by varying the loading thereof.

8. A power system including an internal combustion engine, a generator driven by said engine, means for governing the speed of said engine, a main electrical load, means for connecting said main electrical load in circuit with said generator, an auxiliary electrical load, means for connecting said auxiliary electrical load in circuit with said generator, means dependent upon the fuel intake pressure of said engine for varying the response of said governing means by varying the loading thereof, and means responsive to the connection of said main electrical load for controlling said response varying means.

9. A power system including an internal combustion engine, means for governing the speed of said engine, means including a pressure diiferential diaphragm device dependent upon the fuel intake pressure of said engine for varying the response of said governing means by varying the loading thereof, and means including a valve responsive to the load on said power system for controlling said response varying means, said valve being arranged to vent said pressure difierential diaphragm device to atmosphere at a predetermined load on said power system and to subject said pressure differential diaphragm device to the differential pressure of the atmosphere and engine fuel intake pressure under other predetermined load conditions on said power system.

l0. A power system including an internal combustion engine, a generator driven by said engine, means for governing the speed of said engine, an electrical load, means for connecting said electrical load in circuit with said generator, means including a pressure differential diaphragm device dependent upon the fuel intake pressure of said engine for varying the response of said governing means by varying the loading thereof, and means including a valve responsive to the load on said generator for controlling said response varying means, said valve being arranged to vent said pressure differential diaphragm device to atmosphere at a predetermined load on said generator and to subject said pressure diierential diaphragm device to the differential pressure of the atmosphere and engine fuel intake pressure under other predetermined load conditions on said generator.

11. A power system including an internal combustion engine, a generator driven by said engine, means for governing the speed of said engine, a main electrical load, means for connecting said main electrical load in circuit with said generator, an auxiliary electrical load, means for connecting said auxiliary electrical load in circuit with said generator, means including a pressure dilerential diaphragm device dependent upon the fuel intake pressure of said engine for varying the response of said governing' means by varying the loading thereof, and means including an electromagnetic valve responsive to the connection of said main electrical load for controlling said response varying means, said electromagnetic valve being arranged to vent said pressure differential diaphragm device to atmosphere on connection of said main electrical load to said generator and to subject said pressure differential diaphragm device to the differential pressure of the atmosphere and engine fuel intake pressure when said main electrical load is disconnected from said generator.

12. A power system including a prime mover, means including a governor device having a governor` lever for governing the speed of said prime mover, loading means for resisting the action of said governor, said loading means including a pivoted lever, a pair of resilient elements arranged to bias said pivoted lever toward said governorlever, a stop secured to said pivoted lever and arranged to engage said governor lever under predetermined load conditions to maintain an initial tension in one of said` resilient elements, and means responsive to predetermined load conditions of said prime mover for operating said pivoted lever to disengage said stop from said governor lever except in. the extreme position thereof and to bias said governor lever toward said pivoted lever by both of said resilient biasing elements to provide a predetermined resistance to the action of said governor, said last-mentioned means being arranged to provide a` limited free pivotal movement of said pivoted lever under other predetermined load conditions of said prime mover to maintain engagement between said stop and said governor lever, one of said resilient biasing elements being arranged to maintain said stop in engagement with said governor lever under said last-mentioned load conditions and the other of said resilient biasing elements being arranged to provide another predetermined resistance to the action of said governor.

LA MAR S. COOPER.

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