US1870793A - Speed regulation of engines - Google Patents

Description

Aug. 9, 1932. L. COLLINS SPEED REGULATION OF ENGINES Filed March 27, 1929 INVENTOR Lesferl Cb///I7s ATTORNEY.

Patented Aug; 9, 1932 omen STATES PATENT ornce LESTER IL. COLLINS, OF FRANKLIN, PENNSYLVANIA, ASSIGNOR TO CHICAGO PNEU- MATIC TOOL COMPANY, OF NEW YORK, N. Y., .A. CORPORATION OF NEW JERSEY.

semen REGULATION or ENGINES Application filed March 27, 1929. Serial No. 350,196.

This invention relates to the speed regulation of engines for power purposes generally.

It has special application, however, tocertain,

operations, of which the parallel operation of alternating current generators is typical.

No condition of engine regulation requires greater nicety and exactness of control than that involved in the operation of alternating current generators working in parallel, since such generators can be switched into parallel operation only when they are running in synchronism, that is, when the phase angle between them is zero, or very close to zero. If the machines are not in synchronism any attempt to interconnect them is dangerous; circuit breakers will blow, switches may burn out and even more disastrous results may follow. This is due to the fact that the incoming machine, which is generally unloaded, is usually running at a higher speed than the operating machine with a consequent higher voltage frequency.

The greater the difierence in speed between the machines, the quicker the phase angles will change and pass through the'point of synchronization. For example, if the machines are operating at 337 and 327 R. P. respectively, the period of synchronization is only a fraction of a second, namely, .545 second, while if the speeds are 328 and 327 the period is ten times as long or 5.45 seconds. Thus with machines in substantial synchronization, the periods of phase angle change are relatively slow and permit the operator to execute the switching manoeuvre without difficulty.

In order to follow the phase angle changes a synchronoscope is ordinarily used, which is generally located at the control or switchboard. This instrument may take the form of an electric lamp which brightens or darkens with the phase angle changes and shows a bright light when the phase angle is zero, or it may take the form of a dial with a pointer moving thereacross. Close speed adjustment causes slow changes in the brightness of the lamp or slow motion of the pointer over the dial. Exact speed adjustment is not desired as it causes a stop in the phase angle changes and the point of synchronization cannot be reached.- The operator must judge when he has adjusted the speed of :the incoming machine sufiiciently close to thatofthe operating machine to attain substantial synchronism and then throw the switch. Once the ma-v chines are coupled into parallel operation,

In order to illustrate the invention and the manner ofits use, one concrete embodiment thereof is shown in the accompanying drawin in which:

ig. 1 is aside elevation'al view somewhat diagrammatic in character of a single engine unit; Fig.2 is aright end unit shown in Fig. 1;

Fig. 3 is a longitudinal sectional view on a greatly enlarged scale of the regulator device. In the embodiment of the invention chosen for the purpose of illustration an internal combustion engine of any suitable or desired type is indicated at A having a crank shaft a provided with a fly wheel a, the shaft being directly or indirectly coupled, as desired, to an alternating current generator B. The engine indicated is of the internal combustion elevational view of the solid injection or Diesel type having cylin-' ders a disposed in line with a battery of fuel 7 pumps and injectors at a I A governor shaft or control member for regulating the speed of the engine is indicated at a; Since the details of the engine form no part of the present invention further description thereof is omitted.

The accurate control of the speed of the engine is conveniently accomplished by a speed regulator indicated at C and both manual and power means are provided for the adj ustment of the regulator. The power means and controlled provide for remote control so that two or more complete units of the type shown in Fig. 1 may be arran ed for operation in parallel by an operator at a switchboard (not shown) equipped with one or more synchronoscopes. Since theunits and the regulating apparatus therefor will be duplicates of one another, the disclosure and the description are confined to one unit.

' Referring now to the regul'atorC shown on an enlarged scale in- Fig. -3'-tlie same coin prises a casing 4 having a plunger 5 slidable therein and connected to governorshait a of engine A by a suitable link or arm 6. A considerable portion of plunger 5 is hollow as indicated and the endmembers have bores 5a, and5bslidably receiving a shaft 7 which is journalled ina caper closure 8 threaded into the lower end of. casing 4. A flexible connection'is; provided between shaft- 7 and plunger 5 consisting of a nut 9 within the hollow portion of plunger 5. having screw threaded engagement with threads 7a of limited extent on shaft 7 and serving as an abutment for opposed springs 10 and 11 engaging the inner opposing faces of the end members ofplunger 5. YVith this arrangement plunger 5. has a floating or balanced connection with shaft 7 and its position relative toshaft 7 and casing 4wil1 be determined by the positionof nut 9. A sleeve 12 encloses the major porti'on of plunger 5 and is rotatably mounted in' casing 4, as indicated, a thumb or Wing screw 13 being provided to Sleeve 12 has-a keyed connection with nut 9 through a projection 9a on the;latter which isslidably receivedin an axial sl'ot 12a of sleeve 12.. Plunger 5 is cut: away sufliciently to permit angular and axial movement of projection 9a through a considerable turnin'grange. The entire assembly ofplunger,.sh-aft and sleeve'is insertable through the opening in casing 4 which is normally closed by screw plug- .8. V v

From the above it will be apparent that plunger 5 may be moved axially in Fig. 3 to any desired position of adjustment within the range of the disclosed connections either by rotating shaft 7 while sleeve I2'is heldsta- .tionary or by rotating sleeve 12 while shaft 7 is stationary. Sleeve 12 is knurled or other- .wise roughened on its exterior and provides tor the manual adjustment of the regulator while the power means for adjusting the regulator acts through shaft 7. The power connectioncomprises a flexible shaft 14 having a coupling sleeve 15 in threaded engagement with closure ,8, the sleeve serving as a retainer by engaging a flange 16a on a bearing memberlG which is pinned or otherwise secured to shaft 7'. Flexible shaft, 14-extends toa reduction gear assembly 17 conveniently supported beneath. the operators platform on engine A and is arranged to be actuated by a changing the load. hold sleeve 12 against rotation when desired.

prime mover 18 of any suitable or desired type. The prime mover in the present instance is a direct current reversible motor which may be driven from the exciter circuit for generator B or from an independent source. Leads, 18a extend toa switch diagrammatically indicated at 19 which may be of the button or any other desired type arranged adjacent the synchronoscope on the switchboard so as to establish remote control of the speed of engine A.

The speed regulator C is normally set so that springs name 10 are balancing each other when the governor linkage is in the position corresponding to normal speed and full load. This position of equilibrium is indicated by a mark (not shown), such as a red line, on the regulator casing 4 and the position of regulator nut 9 is indicated by a pointer (not shown) attached to projection 9a. If the position of nut 9'is changed either by rotation of shaft 7 or by rotation of sleeve 12 from the position of equilibrium, the compressiongof one of the springs 10, 11 will decrease and that of the other will increase, the difference incompression of the two springs being transmittedthrough plunger 5 tolink 6 to eiiect a corresponding movement of control shaft 0;; The speed of an idle running engine, normally three per cent higher than the loaded engine, can therefore be brought down to the speed of the loaded engine by suitable adjustment of regulator C without dvhen the operator wishes-to-couple two engme unlts in parallel he watches the synchronoscopes at the switchboard and then pushes the Reverse-. button of switch 19 of the idle engine causing the speed of the "same to drop. Heholds his finger on the regulator C. back into its normal position of equilibrium, indicated when the pointer-0n abutmentnut 9 is at the red indicator mark on housing v4, so as to permit the engine to pick up its proper part of the load. This may be accomplished manually by loosening wing nut 13, then rotating sleeve 12' tobring nut 9 to the proper position. The wing nut '13 must then be'tighten ed inorder that regulation may be possible later through the power connection 14, 17, 18. A somewhat quicker way to'bringing the speed indicator back tothe position of equilibrium will be to hold down the Ahead button on switch 19 until in the operators estimation nut 9 has reached the approximate position of equilibrium and then to make the last exact adjustment through the .manual arrangement previously described.

By limiting the extent of the threads 7a on shaft 7 any likelihood of injury to regulator C is avoided in the event that there should be overadjustment due to holding control switch 19 down for too long a time or due to some trouble which continues motor 18 in operation. If shaft 7' is turned continuously in either direction, nut 9 will merely run off the screw threads 7a and then be held adjacent the same through the balancing action of springs 10 and 11. When the rotation of shaft 7 is then reversed the pressure of the compressed spring will cause the nut to reengage thread 7a and the adjusting function of the abutment nut will be restored.

While the invention has been herein shown in what is now considered to be a preferred form, it is to be understood that the inven-' tion is not limited to the specific details thereof, but covers allchanges, modifications and adaptations within the scope of the ed claims. 7

I claim as my invention: 7 r l. A regulator for an engine governor comprising a casing, a plunger slidablymounted therein, members rotatably mounted in said casing and disposed inwardly and outwardly of said plunger, and means for varying the position of said plunger by retation of either of said members' 2. A regulator for an engine governor comprising a casing, a shaft ournalled therein, a plunger slidably engaging both said shaft and said casing, a resilient connection between said shaft and said plunger comprising a nut in threaded engagement with said shaft and resilient means between said nut V and opposed portions of said plunger.

3. A regulator for an engine governor comprising a casing, a shaft journalled there in, a plunger slidably engaging both said shaft and said casing, a resilient connection between said shaft and said plunger comprising a nut in threaded engagement with said shaft and resilient means between said nut and opposed portions of said plunger, and a sleeve rotatably mounted in said casing and encircling said plunger, said sleeve having a keyed connection with said nut.

4. A regulator for an engine governor comprising a casing, a shaft j ournalled thereappend-' encircling said plunger, said sleeve having a keyed connectlon with sa1d nut, and means for releasably holding said sleeve against comprising a nut in-threaded engagement with said shaft and resilient means between said nut and opposed portions of said plunger, the threads on said shaft being of limited extent so that said nut will run off the same whereby continuous rotation of the shaft cannot cause damage.

6. A regulator for an engine governor comprising a casing, a shaft j ournalled therein, a plunger slidably engaging both said shaft and said casing and having a hollow portion intermediate the ends thereof, screw threads of limited extent on said shaft with in said hollow portion, an abutment nut on the threaded portion of said shaft, coil springs encircling said shaft within said hollow portion and engaging the opposite sides of said nut, an enclosing sleeve having a substantially axial slot therethrough, and a projection on said nut extending through said slot to hold said nut against turningand to indicate its displacement from the central or neutral position.

7. A regulator for an engine governor comprising a casing, a shaft j ournalled therein, a. plunger slidably engaging both said shaft-and-said casing and having a hollow portion intermediate the ends thereof, screw threads of limited extent on said shaft within said hollow portion, an abutment nut on the threaded portion ofsa'id shaft, coil springs encircling said shaft within said hollow portion and engaging the opposite sides of said nut, an enclosing sleeve having a substantially axial slot therethrough, and a projection on said nut extending through said slot to hold said nut against turning and to indicate its position, said sleeve being rotatable on said casing to provide means additional to said shaft for adjusting the position of said nut, and a set screw on said casing for holding said sleeve against turning when said shaft is utilized to adjust said nut.

Signed by me at Franklin, in the county of Venango and State of Pennsylvania.

this 22d day of March, 1929.

LESTER L. COLLINS.

in, a plunger slidably engaging both said shaft and said casing, a resilient connection between said shaft and said plunger comprising a nutin threaded engagement with said shaft and resilient means between said sleeve rotatably mounted on said casing and

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