US1719952A

US1719952A - Electric governor

Info

Publication number: US1719952A
Application number: US732134A
Authority: US
Inventors: Waterous Charles Alexander
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-10-15
Filing date: 1924-08-14
Publication date: 1929-07-09
Anticipated expiration: 1946-07-09

Description

July 9, 1929. c. A. wATERoUs ELECTRIC GOVERNOR 5 sheets-sheet 1 Filed Aug. 1d, 1924 FIG 2 Jvuf/vran MRLE-hrfnaua l A7l 9,952

July 9, 1929. c.-A. wATERoUs ELECTRIC GOVERNOR Filed Aug. 14, 1924 5 Sheets-Shea*l 2 FIG 5 July 9, 1929. c. A. wA'rERous ELECTRIC GOVERNOR Filed Aug. 14, 1924 5 Sheets-Sheet 5 FIG. 6

July 9, 1929- c. A. wATERous 1.719.952

ELECTRIC GOVERNOR Filed Aug. 14, 1924 5 Sheets-Sheet 4 July 9, 1929- c. A. wA'rERous 1.719.952

ELECTRIC GOVERNOR Filed Aug. 14, 1924 5 Sheets-Sheet 5 FG 1i.

FIGJZ Fla. 13.

, Z/ vvfA/TUR Patented July 9, 1929.

UNITED stares CHARLES ALEXANDER WATEROUS, OF BRANTFORD, ONTARIO, CANADA.

ELECTRIC GOVERNOR.

Application led August 14, 1924, Serial No. 732,134, and in Canada October 15, 1923.

suici'entlyleiible .si e applied to a variety1 "of ditl'erentqiu4r ','if desired.

Further objects of the invention are to cnable the device to be applied asa load controller on a motor-driven magazine or other pulp wood grinder, whereby anV exact and constant regulation of the load may be effected.

Other specific objects of the invention will be apparent as thcspecitication proceeds.'

' More general objects of the invention are to provide a device of thisE character in which the various eo-operating parts will each etiiciently perform the functions re quired of them.

In the construction, the invention includes au indicating electrical instrument, an electrical balance such as a Kelvin balance operaliin suitable contacts, two relays operativel y connected with the contacts, two magnetically controlling valves suitably connected electrically. and a controlling member npr-rated by thc valves, all as hereinafter more fully set forth and described in the. accompanying specifications and drawings.

ln the drawings:

Figure 1 is a front elevation of an embodiment of the invention.

Figure 2 is a side view.

Figure 3 is a sectional side elevation.

Figure 3^ is a section detail of the dashpot device shown in Figure 3.

Figure 3B is a detail partly in section of the piston rod and valve stem.

Figure 4; is a rear elevation, partially diagrammatic, showing the terminal boards and electrical connections.

Figure 5 is a front elevation of the electrical balance.

Figure 5^ is a sectional detail of the lower supporting means for the movable element` Figure 6 is a side view of the balance.

Figure 7 is a plan view of the balance, :(3

Figure 7^ is a detail view of the vertical `shaft used in connection with the electrical trating the electrical conneotionsfor the balance.

Figure llis a back view of the lower electrical terminal board.

Figure 12 is a side view of the lower terminal board.

Figure 13 is a. front view of the lowerterminal board. l

In the drawings, like characters of reference indicate corresponding parts in all the views.

Referring to the drawings:

A indicates an indicating electrical instrument which may be of any standard ty-pe of wattmeter, voltmeter, ammeter, power factor meter, etc., according to the character of regulation desired. B indicates an electrical balance, shown as a Kelvin balance, especially wound to give maximum torque in proportion tol Weight, whereby, great relative rapidity of motion may be attained.. -The coils are designed according to the electrical quantity to be regulated, which may be potential, current, voltamperes, watts, power factor, frequency, ete. l

C and D indicate relays controlled by the balance, and E and F are magnetically controlled valves controlled by thc relays, and which in turn regulate the coutrolling device G, the character of which will be described in detail hereinafter.`

H indicates a suitable pedestal or frame, conveniently of cast iron,- upon which the working parts are operatively connected, and which includes a box base l0, a' central section 11, an upper compartment or box 12, and a ease 13 for the electrical instruments, the

sections

10, 11, 12 and 1 3 being convenien tly formed separately and bolted or otherwise secured together as indicated, the lower section 10 being formed around the edge with an annular outwardly and upwardly extending flange 14 which extends to the supporting base and also serves to catch any oil drip.

The box base 10 carries a panel 15 usually of non-conducting material, on which the terminals and such fusesand resistances as may be necessaryare mounted. The Kelvin balance, showiigindetail inFgurfes 5-9 (inclusive) will be -wound for the `'service required, and is mounted upon a suitable panel 16 contained-within the-box 12. The balance comprises movable coils 17 and lstationary coils 18. The number of turns and size 'ot wire usedv .will depend upon thenature of the elect'rical'quantity to be regulated. The stationary coils are fmountedA on .posts 19, from the ends fof .which 4vconducting leads are connected to the relays C andrf-D. mounted on the side ofthe pedestal.

The movable coils 17 arelattached to a lightbut rigid frame 20,- u'sually made of .sheet brass, but which may beimadezof'any other suitable light= and 'rigidmaterial of a nonniagnetienature -To .the top fof this frame 20`is attached a threaded sleeve 21 of Monel lo1; ,other `isui'table'nonj-pclorrodibleA metal. Around the lupper end fofgzthe ,thread ont the sleeve 21 is;wound ja suitable spring. 22 of non-corrodible metal or suitably .protected steel, .which i springsnpports and .controls the moving coils 17 in opposition to the magnetie. force acting `:between the Amovable coils 17l and ithe stationarycoils 18. :This spring thus forms a practically frictionless support for the movingcoilsasdonly molecularv friction .is encountered' in coilin'gior uncoiling a spring. f, z

. The upper end,.ofrthe spring-22 is attached'to thev threaded portion-of an upper sleeve 23, passing -thro, Uhja support 24 mountedon a panel 16. thenpper end of the sleeve 23 vis mounteda-worrn-wheel 25 actuated bya. worin 2.6.,which-can be turned by a. handle or thumbnfut27 from-the outside of the box 12. Thiswormian'd wheel is used to vary the tension of the spring 22 and thereby 4determine or vary, if desired the amount of magnetic Xiforce necessary to maintain the moving coils 17 in equilibrium between the stationary coils 18. =This magnetic force is obtained by drawing from the machine to be'regulated a suitable amount of current by means of transformers or other suitable devices. r

Generally speakingg-current.coils if required are made to carry 5 amperves, 'and potential coils to A.eariyllO volts without overheating, but the balance described can be adapted to any reasonable conditions, the essential: points being that the suspension be nearly frictionless and the magnetic pull or push of the coils be large in .proportion to the inertia of the moving-parts.

To prevent backlash between the worm 26 and the worm wheel 25, a metallic block 28 is provided and pressed by a spring 29 against the worm 26. To further'assist in ,holding the adjusting mechanism in position,a collar 30 is provided on the handle 27, a. spring 31 extending-between the 'collar and the wall of the box 12. This will prevent the handleturning too easily or jarring out of the value it is set at. In order to indicate the direction in which to turn the thumb nut 27 in order to vary the controlled quantity, such as watts,r.volts, amperes, etc., an indicating plate 33 is provided suitably graduated or marked to indicate the direction in which .tovturn Athe knob or thumb nut 27 in order to vary the controlled quantity. The variation obtained is VVobserved -by watching the indicating instrument A.

' vReturning to the frame 20, to the bottom of this ag small bushing 34 is attached. Through this bushing andthe upperbushing 21 passes freely the shaft 35 which is threaded atvboth'ends into sleeves`36 and 37 carrying smallsprings 38 and39 which pass freelyl through vholes in the worm wheel sleeve 23 and in lower support 40 being held in tension by pinsl38^ and 39A. Thesupport 40 supportsal icompensator'rod or lever 50 which-is; fittewvith aboss fitting ina recess in support 4`thus being held centrally. This system of springsl38 and 39 together with the shaft 35fa'nd the :supports referred to, acts asa guide'tothe rame20, maintaining it in central .position, thus- :forming a flexible and almost frictionless positioning l.

means Whidh-is not .likely to be injuredduring shipment or handling. y

. To regulate the speed or movement of the frame 20 and to prevent needless vibrations thereof, a dashpot device is provided including an arm 41 projectinU from thevframe 2O and carrying a fan or blade 42 moving in a dashpot 43 filledv with air or a .suitable liquid designed to regulate the speed of movement as stated. i

The Kelvin balance is designed to be regulated mechanically through the movement of the controlling member G which is communicated to it through the means presently .to vbe described, .and which'include a bell crank lever 44 pivot-ally mounted on the panel 16 and having an operating link or rod 45 extending downwardly and connected to the controlling member by mechanism hereinafter described. The rod maybe conveniently and adj ustably connected to the bell crank by means of a series of holes 46 in the arm of the bell crank to which the rod 45 `is attached. The other arm of the bell crankis adj ustably connected to an adjustable rod 47, as, for example by an eye or sleeve'48 with which the rod 47 has screw-threaded engagement, the said eye or sleeve being connected to one of a series of perforations 49 in the bell crank.

The opposite end of the adjustable rod 47 is connected to the lever 50 which rests on the lower support 40. The lever 50 is provided with a threaded hub 51 to which is attached the compensating spring 52 which extends upwardly and is attached to a th-readedbushing 52A. This bushing 52A is provided with two pinson its upper face so arranged as to engage in holes in the lower member of frame 9.0,with the object of transx'nitting the torque of the spring without causing any lateral displacement of frame 20. The end ofthe lever is connected to a spring 53,-the other end of which is adjustablyl attached to a bracket 54 as, for instance,.by means of athreaded -pin 55 connected to the springand having screw-tlnea-ded engagement with the bracket. TheE frame .20 carries suitable controlling making and breaking means, which means, as illustrated, include an arm 56 (see;Fig. 8) carrying a suitable insulated stud 57 .onwhich is mounted .a wiper spring 58 carrying a suitable wiping contact. point 59 swinging bef tween,.adjustable. stationary 'contact oints fastened to4 rods .60 and 61 which can e adusted toregulatethe free swing of the contact 59. The Aconta-ets areusually made of .platinof-iridium. Thesmall spring 58v gives a wiping laction, which keeps the contacts cleana-nd makes sure contact- -1t is advisable, ito avoid annoying repairs, that the current passing betweenthese-contacts .be small, and

lthe Ismall5 s parle can .be further subdued by -suitablehigh 4resistances'62 and 63 connecte in paralleliwith the contact points.

From the stud .57 a .flexible wire'64 runs to a terminal 65. From the adjustable ,sta-

tionar-y contactrods `60v and 61 conducting .postsl9 lead toterminals 8 and 9 and from these bysuitable .wiring to the-coils of the relays-G and D.. A current from an independent source o supply suitable for operatingrelays -C and .D is ledby suitable wiring -to terminalfand to the relay coils, and this 'current can thus be passed through orvbroken by the moving contact 59 as it-swings between .the-adjustable

stationary contacts

60 and 61. The movable coils 17 are connected through flexible leads to terminals 59^, 60^ and 61? as shown in Figures Sand 9 and thence lo the controlled machine or system. 'lhe stationary coilsv18 are also suitably connected to thesame controlled machine or system.'

The relays C and D are conveniently mounted on the sides of the pedestal H as illustrated orthey may be placed in any suitable location at any reasonable distance from the apparatus.4 These relays .are similarly constructed. v v

When it is desired to control an electrical quantity through the 'intervention of a hydraulic piston rather. than by electrical means exclusively, the current made. and broken by the-relays C and D is conducted by suitable wire-s to the magneticvalves E and F whichmay be placed in anysuitable location not necessarily near the relays but to which .they are connected by suitable conducting wires.

These valves each comprise a fluid-tightv bodyor casing of magnetic material provided with a cover `81 and vareoJerativcly connected to the controlmember by suitable conducting conduits through which the working fluid, usually oil, may pass, control valves 106 of any convenient design being provided for these conduits.

The control member G includes an operating piston 107 in a cylinder 108 the position of which is controlled by the magnetic valves E and F. One valve admitsfluid under pres.- surc to the underside of the piston and the other valve when open permits this fluid to escape. The working fluid under pressure is supplied by a pump equipped with suitable pressure regulating means and with a tank to receive the fluid returned from the governor, all being-of well known construction.

When the Huid is 'admitted to the under side of the piston 107 in thecylinder 10.8,'the piston rises-against'the compression 'of a spring 109.- This spring is made of considerable length lto avoid great diterenceginfpres'- sure on the piston107 in -upper and lower 'positions.- f The spring is held by asuitable casingv or sleeve 110 having threaded engagement with'a' supporti'ng'cover 111 which vis .bolted or otherwise.secu1ed.to the -to of the cylinder 108, the -contactsgbeing-su eiently tight to prevent any dust, etc.,'reaching the piston 107. -z j The piston 107 -is preferably a ground tit in the cylinder 108 to. thereby ensure prompt and positive aetion-witl1out undue. friction. The piston is preferably grooved circumferentially, toreducef' leakage. The fluid used is preferably incompressible, andthe 'pressure available should be sufticient-to, promptly overcome frictional resist-ance so that. the piston 107 will followV withoutlexcessive-time lag, the indications of the `measuring elcinent as transmitted through the relays and lnagentic valves.

To ensure .smooth action without cutting or leakage, the piston 107 is made of ample length in lproportion to diameter, and the spring force is applied. at the centre of the bottom of the 'piston through a ball contact including a ball 112 held in the central seat 113 in the piston 107, and engaged at its opposite side by a pressure plate 114 against which a spring 109 bears.

The upward movement of the piston is limited in any suitable well known manner so that the upward limit of travel of the piston may be set and adjustedtosuit the requirements of the controlling element that is to be moved by the-piston' To the piston 107 a piston rod 117 is connecte-d by a flexible joint 118 which passes through a gland 119. The pist-on rod ispreferably aground [it in the'gland, to reduce friction and which latter is grooved to prevent excessive leakage. The end of the piston rod is designed to be flexibly connected to the controlling element which may be a valve, a l

'poiver required todri-ve the same.

The valve J comprises a sui-table bo'dy or casing 121fin which Works a valve 122, the stem 120 of which is groovedcircumferentially and is aground fit in body so as towork freely with asmall amount of leakage. Re-

duction of friction is'more' important inthis case-than reduction o f leakage. lThe 'valve 122 itself is so shaped as' to give aiflow proportional to thelift,thus' avoiding sudden changes'f flow which would increase 'the hunting tendency of the governor. This valve 'and stemshouldl'b'e made of durable material such asfMon'el metal,;haird bronze'or stainless'steel, or such'other metal as is* suit.- able for use withrthe fluid controlled.

The valve seat 123 isremovable so that'it can be replaced in casevofwear and consequent excessive leakage; A set or stop screw 124 is provided in a removably threaded plug 125 beneath the valve'seat designed=to limit the downward travel ofthe-valve to prevent it sticking on its seat, and to maintain a minimuln rate of flow, as described. A suitable cap 126 may be provided around the lug to prevent leakage or unauthorized adjustment ofthe stop screw.

The cylinder 108 and the valve casing are conveniently joined by asuitable junction piece or member 127 which maintains proper alignment and dista-nce'between them. The cnd of the piston rod 117 and the valve stem 120 are rounded and touching so as to prevent incorrect alignment causing jamming of any parts. Around the end lof the iston rod 117 and the valve stem 120 is place a loose sleeve 128 through which passes a pin 129 which is operatively connected to the Kelvin balance by the connecting means to be presently 'described.

These connecting means include a lever 130 connected by a free-working pin joint to the sleeve 128, said connection including the pin 129. The fulcrum of the lever 130 is made adj ustable. which is accomplished in the elnbodiment illustrated by forming the fulcrum on a sliding block 131 which can be adjusted in position by the screw 132 and knob 133, the latter projecting beyond the side of the pedestal H.

The end of the lever 130 opposite to that which is connected to the sleeve 128 is connected to a link 134, the opposite end of which is pivoted to a sliding dashpot 135 Which slides in a guide 136. Within thc dashpot 135 is a piston 137 with a holeuthrough its centre, this `piston is connected to the hollow pistonl rod 140.' A spring 138 extends between the fixed bracket 139 through a clearance hole in the cover of the dashpot to the piston 137 to which it is fastened to regulate the position and speed of movement of the piston. A'rod is located inside the hollow piston rod 140. This rod 45A is enlarged and tapered atthe lower end so that when operated' it gradually opens or closesholes 139a through the side ofthe hollo'wpiston rod 140 by means of which th'e rate of flow offliquid from side to sideof the piston 137 throu'gh'thehole in the piston137 and the holes in the hollow piston rod-140 may be varied. There is attached to the top ofthe hollow' piston rod'1'40' a cap 163threaded to :'itthe upper end of rod 45A. To the upper end of rod 45A is attacheda knob 142 by means of which the 'rod 45A can be rotated and thereby raised oril'owered in the hollow `piston rod'140.f'"To the cap 163 is attached a I oopor btlier l'suitable"connec'tion engaging with rodV 'orlink45 'leading to bell crank as 'previ1:islyjdescribed.l ',Ih'e dashpot is lfilled with"afsu'itabl'e liquid to regulate the speed 'of movement of thepiston 137 and the other 'moving parts connected thereto. It ivill-be seen `'that the 4dash po't device just described and the system of levers, referrredlto, transfer a portion of the'movement of the pistonrod 117 and the valve stem 1,20 b a'ck to 'the movingframex 20, the-amount transmitted varying'according to the extent and speed of movement of said pistonirods, and thereby' preventing the swinging or'- overrunningA action of the regulator commonly 'known as hunting. The system of levers thus functions as a compensator and permits rapid governor action Without over-running.

Figures 11 and 13 and 12 showthe arrangement of the terminal board 15 vwhich is mounted in the base box 10 and used to carry the terminals connected to the leads from the control machine. The arrangement and size of these parts will vary with the quantity to bc controlled and the specific manner in which the governor is applied. The arrangement illustra'ted is'that required With the Wattmeter type of governor which is applied to control a pulp mill grinder or similar machine.

- 143,144 and 145 are terminals-connected to the potential supply of the grinder motor by means of suitable potential transformers. 146, 147 and 148 are fuses to protect governor parts. 149, 150 and 151 are connections to

resistances

152 and 153 and balancing resistances 154 which are used to supply proper and equal currents tov the moving coils 17. 155 and 156 are resistances to control the potential supply to the indicating wattmeter A.

157, 158 and 159 are terminals to which are connected the current leads from current transformers in the main circuit of the controlled mot/0r. Suitable Wires run from ter` llU minals 157 and 159 to short circuiting switches 160 and 161 which are used to short circuit the current transformers when starting motor or adjusting or repairing governor. From these switches wires are run to the stationary wattmeter coils 18 of the Kelvin balance and also to the coils of the indicating wattmeter A.

The board shown is for three phase service, land a similar but differently arranged board would be required for other service, such as two phase or direct current.

A sight glass 162 may be conveniently provided consisting in part of a lass tube whereby the rate of flow of the woiring fluid canv be inspected while the governor is in action.

It will be seen that, in operation, the moving coils are suspended by a spring which balances the torque when a desired quantity is being maintained. The resistance of the spring can be varied by the fine adjustment, already described. Furthermore, the complete spring suspension and guide is of such a character as to be almost frictionless and not likely to be injured by variation or by shock in shipping, and is designed to maintain its frictionless properties indefinitely.

Any unnecessary variation or fluttering is restrained by the vane l2 which enables practically dead beat regulation to be maintained. The size and flexibility of the vane or paddle and the viscosity of the fluid may be varied to suit conditions.

The connection of the main controlling element to the Kelvin balance, as described, has a compensating action which reduces overrimning or hunting.

It will be seen that in operation, the fluctuation in electrical quantity indicated by the balance B will cause energization of one or other of the controlling relays C and D which, in turn, will operate one or other of the magnetically controlled valves E and F. which will operate the controlling element G as already described, the operation of which will etici-t the desired regulation. In turn, the operation ot the controlling element G, through the compensating levers already described, will mechanically aect the Kelvin balance to prevent overrunning.

As many changes could be made in the above construction and many widely different embodiments of my invention within the scope of the claims, constructed without departing from the spirit or scope thereof, it is intended that all matter contained in t-he accompanying specification and drawings shall be interpreted as illustrative and not in a limiting sense.

lhat I claim as my invention is 1. An apparatus of the character described comprising, in combination, an electrical balance, relays controlled thereby, magnetically controlled valves controlled by the relays, a controlling device operated by the valves, mechanical connecting means between the controlling device and the balance, including a lever with adjustable fulcrum.

2. An'apparatus of the character described comprising, in combination, an electrical balance, relays controlled thereby, magnetically controlled valvescontrolled by the relays, a controlling device operated by the valves, and mechanical connecting means between the controlling device and the balance including a lever, an adjustable ulcrum block for thc Icontrolled valves controlled by the relays, a

controlling device operated by the valves, and mechanical connecting means between the controlling device and the balance including a bell crank having one arm operatively connected to the controlling device and one operatively connected to the electrical balance, and an adjustable spring connected to the bell crank.

5. In an apparatus of 'the character dcscribed and in combination, an electrical balance having a suspending spring, a worm wheel connected thereto, an adjusting worm for the worm wheel, relays controlled by the balance, magnetically controlled valves controlled by the relays, and a controlling device operated by the valves.

6. An apparatus of the character dcscribed comprising, in combination, an electrical balance, relays controlled thereby, magnetically controlled valves controlled by the relays, a controlling device operated by the valves, a fluid Valve operatively connectcd to the controlling device, connecting means between the controlling device and the 'Fluid valve, and operating means extending from the said connecting means to the electrical balance.

7. An apparatus of the character described, comprising, in combination, an electrical balance, having a suspending spring, a worm wheel connected thereto, a spring held rod, a worm on the rod for the worm wheel, an operating knob on the rod, relays controlled by the balance magnetically-controlled valves controlled by the relays, and a controlling device operated by the Valves.

8. An apparatus of the character described comprising, in combination, an elcctrical balance having a supporting and susllO pending spring, a worm wheel connected to the suspending spring,.:an adjusting Worm for the worm wheel, a compensator rod connected to the supporting spring, relays controlled by. the balance, Amagnetically controlled valves controlledby the relays, acontrolling device operated by the valves, and a connection between the compensator rod and the controlling device.

9. .An apparatus of the character described comprising in combination, an electrical balance lhaving a supporting and suspending spring, a worm wheel connected to. the .suspending spring, an adjusting worm forrthe Worm wheel,a compensator rod connected to the supporting spring, a springheld rod extending inside the two springs, relays controlled by .the balance, magnetically controlled valves, controlled by the relays, a vcontrolling device operated by the valves, and a connection between the compensator rod and the controlling device.

. 10. An apparatus .of thel character described comprising, in combination, Van electrical balance vhaving a supporting and suspending spring, a Worm `wheel connected to the suspending spring, an adjusting worm for the worm wheel` a compensator rod connected to the supporting spring, a horizontally eX- tending resilient member connected to the compensator rod, relays controlled by the balance, magnetically controlled valves controlled by the relays, a controlling device operated by the valves, and a connection between thc compensator rod and the controlling device. j

l1. An apparatus of vthe character described, comprising-in combination, an electrical balance, including a hollow. sleeve and a hollow hub, a worm wheel at the end of the'sleeve, an adjusting Worm for the Worm Wheel, a Spring in the hollow sleeve and a spring in the hollow hub, means to retain the springs in theirfrespective bores, a small sleeve carried by each of the springs, a rod joining the small sleeves, a suspending spring secured'to the hollow sleeve, a supporting spring secured to .the hollow hub, acompensator rod carrying theliollow hub, relays controlled by th'e balance,:magnetically controlled-valves cont-rolled by the relays, a controllingdevice .operated by the valves, anda connectionbetween the compensator rod and `the Controlling device.

12. A n apparatus of A4the character doscribed comprising in combination, an electrical balance, relays controlledthereby, magnetically controlled valves controlled by the relays, a' controlling device operated by the valves, and'adjustable,compensating connectA ingmeans between thecontrolling device and the valves including a dash pot device.

13. An`.electric governor comprising an electric balance, contacts operable by said balance, relays operatively associated with the contacts, magnetically controlled valves suitably ,connected electrically, a springpressed controlling member ,operable by the valves, and an indicating electrical instrument operatively associated with the balance.

In witness whereof I have hereunto set my hand.

CHARLES ALEXANDER WATEROUS.