US3854695A

US3854695A - Electromagnet control apparatus

Info

Publication number: US3854695A
Application number: US00293007A
Authority: US
Inventors: B Baugh
Original assignee: Vetco Offshore Industries Inc
Current assignee: FSSL Inc
Priority date: 1972-09-28
Filing date: 1972-09-28
Publication date: 1974-12-17
Anticipated expiration: 1991-12-17
Also published as: FR2201419A1; JPS5815722Y2; JPS5456232U; NL7313437A; GB1403945A; NL157976B; FR2201419B1; JPS4971516A

Abstract

A control for operating a fluid actuated device includes an electrically actuated pilot valve for controlling flow of pressurized fluid to the device. The pilot valve has an electromagnet for actuating the valve against a high resistance to being initially opened and a much lower resistance to being maintained in the open state. An electrical control circuit initially introduces a high potential to the electromagnet to open the valve and subsequently introduces a low potential to the electromagnet to maintain the valve in the open state, whereby the fluid activated device is maintained in the actuated state with significantly less power than that used to initially actuate the device.

Description

[75] Inventor:

[73] Assignee: vetco Offshore Industries, Inc.,

Baugh 1 41 ELEcTRoMAGNET CONTROL 9 APPARATUS Benton F. Baugh, Houston, Tex.

7 Ventura, Calif..

[221 Filed: Sept, 28, 1972' I 21 Appl. No.2 293,007

.52 u.s.'c1' 251/129, 317/154, 317/010. 4

f 1451 Dec. 17, 1974 Primary Examiner-Arnold Rosenthal Attorney, Agent,- or Firm-Bernard Kriegel [57] v v I 7 ABSTRACT A control for operating a fluid actuated device includes an"electricallyactuated pilot'valve for controlling flow of pressurized fluidto the' device. The pilot valve has an electromagn'et for actuating" the valve against a high resistance to being initially opened and- 3 a much lower resistance tobeing maintained in the open-state. An electrical control circuit initially introduces a high potential -to the electromagnet'to' open the valve and subsequentlyintroduces a low potential to the electromagnet to maintain the valve in the open that used to initially actuate the device.

7 Claims, 7 Drawing" Figures 51 1111.01 H0lh 47/04,*1=161 31/06 {58], Field of Search 251/129, 141, 68; 317/154,

' '3l7/DIG.4

I [56] References Cited UNITED STATES. PATENTS 3,371,252 2/1968 James ..3l-7/DlG.4. 3,469,818 9/1969 Cowan 251 129 FOREIGN PATENTS QR APPLICATIONS 1,028,845 4/1958 Germany 251/129 PAIENIED m1 H914 3.854.695 SHEET 10F 4 sum 2 or 4 mum-10mm 1 m4 I I w w Em mm w QM ,m KM s Mm v m wa QM NR. /A\ k v, MN wmw m \m\ R MM R Q MW Mu, WW. RM. WWW

PAIENIEU mac: 7 am saw u or 4 ELECTR'OMAGNET Omani-mus The-present invention relates generallyto controls.

for reducing the'power consumption of-an electromagnetand more specifically to electrically operated-de- I vices for determining-theflow of fluid to-a fluidactuated device. I Whena well isdrilled in relatively deep water,.as.

from an ocean floor, it is often desirableto .drill and v complete the well at the-ocean floor with-devices which can'be remotely controlled from a location above the' surface of thewater. A plurality of these devices, which may include blowout preventers, hydraulic connectors,

and valves,'may be employed in controlling different functions on a single -well. Usually'these devices are re motely operated by a pressurized fluid which is con-- pilot valves. When 'asolenoid is energized,'thefpilot valve is openedja'nd thepressurized fluid is directed to the device. t v

In the past, apparatus for controlling the energizing ofthe solenoid or electromagnet in each of the pilot valves has included a source of relatively high operating potential and a switch for' selectively introducing the high potentialto the electromagnet. Thus, by oper-- ation of the switc'h,'the electromagnet has been-ener g'iz'ed to'open or' otherwise' activate-the valve and acti vate the deviceltis often necessary to activate the devices for an extended period of time. Under such circumstances, the

high potential introduced to each 'solenoid is' continued 'in maintaining the pilot-valve in its-actuated or open state. However, at the" relatively high energizing potential,.each pilot valve previously used has consumed as trolled byappropria'te actuation of 'solenoid'actuated' much as 360 watts' of power. The generation of electric power at the offshore location of a subsea well is expensive, the high power consumption of eachvalve being v correspondingly costly. This problem has been compounded bythe' multiplicity of pilot valves which may be provided ateach well. For example, a typical instal lation including seven pilot valves has previouslyconsumed about 2,500 watts of power. In order to carry.

this amount of electricity to the remote locations, such as the ocean floor, large expensive transmission lines arerequired.

The high power consumption has also been critical energized over an extended period of time, the solenoids or electromagnets have overheated, resulting in with respect to the reliability of the pilot valves.' When their unreliability and failure. Failure of a pilot valve obviously requires its replacement at great cost.

In the present invention, a pilot valve includes an electromagnet having a coil and a plunger or armature initially biased to an extended or one position when the coil is deenergized, and drawn to another or proximate position when the mills energized. This movement of n the plunger opens or otherwise operates a valve connected to the plunger, controlling the flow of a pressurized fluid that actuatesa device.

A relatively large-force must-be used to intially' overcome the bias on the plunger, However, once the plunger is in its proximate position, a force of signifi cantly less magnitude can be relied upon to maintain this disposition. For example, when the plunger is in the extended position, about 360 watts may be required to move the plunger to the proximate position; however,

the plunger can be maintained "in the: proximate, positioniwith only about two-watts of power.

Inone example of the? invention, acontrol apparatus is-providedwith a first source ofrel ativelyi low operating potential'and a second source (if-relatively high o'pera't-ing potential. A .flrst relay-,- havingfirstand second sets of vcontacts,.and.a second-relay, having third and fourth sets of contacts,'are alsoprovided. The. second source of operating potential is'introduced through the fourth set of contacts to'th'e coilof-the electromagnet.

' The first potential is introduced through the second and third-sets of contacts to the coil .in the electromag net. A-coil in each of the first and second relays is connected through a first switch to the first source of operating potential. 'Additionally,'the coil in' the first relay is connected through the'first contacts and'a' second v switch'to the first-source. of operating potential. Except forlthe second switch'and-"the third-ContactsQeach of the contacts and switches is normally open. v When the first switehis closed, thefirst'and second relays are activated "so that the high potential; is

will be-deactivatedso thatth'e low-potential is introduced to'theelectromag'net. This low potential can 3O v shifted by the plunger in moivingtoitsproximate position, until-the second switch isopened andthe plunger maintain the pilot valve the state to which it has been is returned orbia'sed to. its extended position;

These features of the control apparatusv are of signifi- I cantadvantage, especially where electromagnets and solenoids .must be actuated at remote locationsifrom the control apparatus. Whereas seven of the devices of theprior art, for example, mightconsumeasmuch as about 2,500 watts, the device of the present invention would consume only. about as much power as a 15 watt light bulb. Not only. is the cost of the electricity consumed lower, but the size of-the transmission lines can I be substantially decreased. Furthermore, ;the. pilot valves will not overheat making them considerably more reliable over extended periods than the devices of the prior art." v v This invention possesses manyother advantages, and

has other purposes'which may be made more clearly apparent from a consideration of a form in which it, may be embodied. This form is shown in the drawings accompanying and forming part of the present specifi-.

cation. It will'now be described in detail, for the-pun pose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limited sense.

Referring to the drawings:

? FIG, 1 is a side elevation 'view'of a completioncon trol pod-including a control valve and a determining its operation; v

FIG. 2 is a longitudinal cross-section of the pilot valve illustrated in FIG. 1;

pilot valvefor FIG. 3 is a longitudinal cross-section of the control valve illustrated in FIGII; I t

FIG. 415a schematic view of a control circuit for electrically actuatingthe pilot valve, wherein the controlcircuit is disposed in a first mode of operation;

'tion; and

FIG. 5 is a schematic view of the control circuit illustrated in FIG. 4 and disposed in a second mode of operation;

FIG. 6 is a schematic view of the control circuit illustrated in FIG. 4 and disposed in a third mode of opera- FIG. 7 is a schematic view of the control circuit illustrated in FIG. 4 and disposed in a fourth mode of operation.

To satisfactorily complete a well on the floor of the ocean, numerous fluid actuated devices, such as flowout preventers, hydraulic connectors, and valves are employed. Onesuch fluid actuated device 11 is illustrated schematically in FIG. 1. A completion control I pod 13 is adapted to have a high pressure fluid line as- A pilot valve 21 is connected to the signal wires 17 I and communicates with the supply hose 19, providing ameans for controlling fluid flow to the fluid actuated device 11. This pilot valve controls the flow of fluid to a controlvalve 31, that, in turn, controls the flow of the fluid passing through the

lines

15, 19 to the device 11.

Actually, a plurality of sets of apilot valve 21, control valve 31 and fluid actuated device 11 are disposed at the ocean floor to control differentfunctions relating to the well extending downwardly from the ocean floor. However, for simplicity of illustration, only a single set of pilot valve, control valve and fluid actuated device is illustrated in the drawings. I

The control pod l3includes a mainbody 12 having a passage 14 therethrough connected to the supply hose 19 for conducting fluid under pressure to an inlet or supply of the pilot valve 21. This port communicates with. an inlet passage 25a in an outer body 25b that communicates with a passage 67 in a pusher 67a disposed within a radial opening 67b in an inner valve body 25c, this pusher member bearing against a radial shear seal 25d extending inwardly of the body 250 and adapted to bear against the upstream side of 59a of a gate valve 59 movable longitudinally in the inner body. The pusher member is adapted to be acted upon by the fluid'pressure in the inlet passage 25a to be urged inwardly and to be retained in sealed relation against the seal element 25d, in turn holding such seal element 59a of the gate valve bearing against the upstream face member.

As disclosed in FIG. 2, the pilot valve 21 is in a closed position, in that a lateral passage 61 extending through the gate 59 is out of alignment with the shear seal 25d. The gate valve is located in the closed upper position, illustrated inFIG. 2, by engagement of an upwardly extending shoulder 59b thereon against a companion to the outer body member 25b, as by means of screws 201. The 'gate'valve member 59 is shiftableto an open condition, as described hereinbelow', to bring a lower stop shoulder 202 thereon against a companion lower shoulder 203 on the inner valve body 25c, which effects alignment ofthe transverse passage 61 through the gate valve member with the inlet shear seal 25d and also with an outlet shear seal element 204 bearing "against the downstream side 205 of the gate valve member, the element 204 engaging aradially disposed 'pusher mem-- ber 206 mounted within the valve body 25c, the fluid flowing through the shear seal 204 and the pusher member 206 into an outlet passage 29a communicating with an outlet port 29 that, in turn, communicates with an outlet passage 29b extending to an inlet port 39 of the control valve 31. i

When the gate valve member 59. is in its upper or closed position (FIG. 2), the fluid in the outlet passage 29a can exhaust through the downstream pusher member 206 and shear seal 204 into an exhaust passage 63 provided in the gate valve member, this exhaust pas-- sage opening into an outlet passage 27a in the valve body 25c extending to an exhaust port member27 that communicates with a suitable exhaust line (not shown) that may extend to any suitable location, as to the vessel or drilling platform at the surface of the water.

To facilitate shifting of the gate valve member 59, which is a flat, plate-like member, between its closed and opened positions, its downstream face 205 bears v against spaced rollers 65 suitably rotatably mounted in the valve body 250, as through the aid of needle bearbeing slidable within a companion bore 221 in the inner valve body 25c. Similarly, the upper portion 222 of the valve member is cylindrical, being slidable through a companion axial bore 223 in the adapter 200, this upper cylindrical portion being suitably secured to a I I valve operating stem69, as by means of transverse pins 229. The outer stem is disposed within an'electrornagnetic or solenoid assembly 41 suitablysecured to the adapter 200. I

The solenoid assemblyincludes-anouter magnetic core 51 secured to an inner magnetic core 52 by radial "screws 53 bearingv against a tapered face 54fon the .lower flange 55 of the inner core, which bears against a downwardly facing shoulder 55a in the outer core 51.

I Between the inner and outer cores is disposed the coil 47 of the electromagnetic or solenoid, the windings of which are connected to the signal wires 17, that may extend through the hose assembly 15 to the operating shoulder 590 on an adapter plate 200 suitably secured location on the drilling vessel or platform at the top-of the water. The pilot valve 21 is initially urged tothe closed position, illustrated in FIG. 2, by a helical compression spring 57, the lower end of which bears against a shoulder 56 on the inner core 52 and the upper end of which bears against a magnetic plunger 53a threadedly or otherwise suitably attached to the upper end of thestem 69 and locked thereto by. a suitable lock nut 240 threaded on the stem. When the circuit to the solenoid'4l is open, the spring 57 pushes the valve stem 69 and 'the plunger 53a to an extendedposition, the inner tapered end 241 of the plunger being spaced from the companion tapered end 242 of the inner core 52 by a predetermined distance, providing a gap 55a therebetween. A sleeve 243 is clamped between the upper end of the outer core 51 and an upwardly facing shoulder r 244 on the inner core 52, the periphery 245 of the. *plunger 'or'armature 5311 having a suitable clearance with respect to su'ch"sleeve.' v

'When the circuit'to' the solenoid coil 47 is completed, the plunger-53a is'attracted iriwa'rdly'to shift the gate valve member 59 to the open position in which its lat-- eralpassage 61 is in alignment with the shear plugs d,

1 204; This position is determined bythe engagement of thelower stop shoulder 202 with'the companion sho'ul der 203 in the inner valve body 250. At this time, the

gap 55a between the plunger 53a and the inner core 52 has been reduced considerably. By way of example, the

, spring 57 to shift the pilot valve to its initialposition in gap 55a, priorto the energizing of theelectromagnet,

may be about 0.200 inches; whereas, the gap 55a, with the electromagnet energized, may be about 0.030

inchesL-Thus, in thespecific pilot valve'21 disclosed, it is initially disposed in a closed position when the electromagnet isdeenergized, and'is shifted to the open position and retained in such open position when the electromagnet is energized. I i

, The control valve 31 includes a ing an actuating port member 301 communicating with the outleto'r discharge passage 29a, 29b of the pilot valve, anoutletport member 302 communicating with the passage'37a in the pod body 12 that leads to the fluid activated device 11,, a supply port member 303 va ve body 300 hav} communicating withthe source of fluid pressure flow- 1 ing through the passage, 14in the body from the'high pressure hose '19, and an exhaust port member 304 communicating with an exhaust passage (not shown) that may extend to a suitable exhaust line (not shown).

A shiftable valve member 305 is. movable within the f valve body 300, this valve member extending across the exhaust, outlet and

inlet port members

304, 302, 303.

As disclosed, the inlet 303 is' closed, but-the; passage cates througha passage'310, 310a, 3l0b in the shiftable valve member with the exhaust port member 304,- as illustrated inFlG. 3. The valve member 305 is'shifted and'retained in this position by a helical compression spring 311 disposed within-the valve body housing ex- .te'nsion300a, the outer portion of the spring bearing against an end wall 312 of the housing, and the inner portion'of the spring bearing against a head 313 threadedly or otherwise suitablysecured to the movable valve member 305, shiftingv a shoulder 314 on this valve 37a leading tothe fluid activated device 11 communimember into engagement with a companion stop shoulder 3l5.in the valve body 300. At this-time, the passage 37a leading to and from the fluid activated device 11 is in an exhaust condition, in which no fluid pressure is suppliedto'the device 11. When the electromagnet coil 47 is energized to pill the plunger 53a inwardly, which acts through the valve stem 69 to shift the gage-member 59 to the valve opening position, at which its transverse passage '61 is aligned with the shear seals 25d, 204, fluid under pressure. flows through the line 29a, 29b and through the seal sub 301 that communicates with the head end 320 I of a cylinder 321 containing thepiston portion 322 of theshiftable valve member 305. The fluid under pressure shifts the valve member305, as to the right illustrated in FIG. 3, to place the port 31011 in communication with the inlet po'rt303 and the other port '310b in. communication with the outlet port 302 of the control valve 31. This position is determined by engagement of a shoulde'r325 on the valve member 305 with a com- .l0wer operating potentials.

panion shoulder 326 on the closure portion 327 of the A control'valve'body. Fluid under pressure Jc'an then flow from'the supply hose 19 to the inletport 303, and then through the valve memberpassages 310a, 310,310b,to the-outletport302, and then through the body passage 37a-to the fluid activated device 11. The deenergizing A of the solenoid or electromagnet 41 will cause the which the fluid passage 2%, 29a communicates through the exhaust path 63 in thegatev'alve '59 to the 1 exhaust line 27a,there by.relieving the fluid1.pressure in the cylinder .321," which willthen permit the control valve spring 3ll.to shift the valvemember 305'back toits initial position,.in which the fluid line37d leading-to the fluid activated device 1 1 communicates through the

path

302, 310a, 310, 31017 to the exhaust port member 304 and the exhaust line.

In both the pilot valve and the control valve,suitable seal rings are provided to prevent fluid'leakage between the several parts, as shown.-

' The -present invention involves plunger 53a can be maintained in itsproxirnate position with'less power than that used told'rawthe plunger-53a from its extended position to its proximate position.

This can be'generally explained with reference to the dimensions of the gap a; When the gap 55a is relaremain activated for an extended period of time. This not only will reduce the consumption of power, but also the'heatbuildup-within the pilot valve 21, A

An electrical circuit71 providing these advantages is illustrated schematically in FlGS. 4 through'7. Generally, the electrical circuit 71 includes first and second' sources of operating potential73 and 75, respectively. The ,first'source 73v provides'a relatively low p otential,

such as 24 volts, while the second source 75 preferably provides a'relatively high potential, such as volts.

Switching means, shown generally at 77, is connected "to the sources of potential 73 and 75 to selectively energize the pilot valve 21 with one'of the higher and The switching means 77 can include a first relay 79 having a coil 81 and first and second sets of contacts 83; and 85, respectively. A second relay 87 can be similarly provided with a coil- 89"and third and fourth sets of

contacts

91 and 93, respectively. The first, second and fourth contacts, 83, 85 and v93, respectively, normally provide an open circuit while thethird set of contacts 91 normally provides a closed circuit.

' A normally open switch-95 is connected between the first source 73 and the coils 81'and 89 to selectivelyenergize the first and second relays 79' and 87, respectively, with the lower potential. The coil 81isalso connectedto one of the first contacts 83. The other of the first contacts 83 is connected through a normally closed switch 97 to the first source of operating potential 73. I

the fact that the A conductor 99 provides continuity between the first source 73 and one of the second contacts 85. Similarly, a conductor 101 provides continuity between the other of the second contacts 85 and one of the third contacts 91. The other of the third contacts 91 is connected through the signal wire 17 to the connector 45. A third conductor 103 is connected between the source of operating potential 75 and one of the fourth contacts while the other of the fourth contacts 93 is connected through the signal wire 17 to the connector 45. The normally open switch 95 and the normally closed switch 97 are preferably push button switches which are biased to provide their normal characteristics.

The structural features set forth above provide the switching means 77 with at least four modes of operation. A first mode of operation, wherein the coil 47 of the pilot valve 21 is deenergized, is illustrated in FIG.

4. With each of the

contacts

83, 85, 9 1 and 93, and

each of the

switches

95 and 97 disposed-in their normal states, as previously described and illustrated-in FIG. 4,

the coil 47- is deenergized so that the pilot valve 21 and control valve 31 are in their exhaust conditions, the device 11 being deactivated. g I

When the push-button switch 95 is closed, the first and second relays, 79 and 87 are energized. In this second mode of operation, illustrated in FIG. 5, the first, second and

fourth contacts

83, 85, 93 provide closed circuits, whilethe' third contacts 91 provide an open circuit. This-enables the source of higher operating po- I pressure to flowinto the control valve member 305 to its open condition in which fluid under pressure can flow from'the pressure line 19 through the inlet and

outlet passages

14, 37a to the device 1 1, to actuate the latter.

It will also be noted that theenergizing of the relay 8 button switch 97' is released; it returns to its normally closed state, and the circuit 71 returns to its first mode of operation (FIG. 4).

The

switches

95 and 97 can be disposed on an operating panel (not shown) to provide the simplest of operating procedures whereinthe push button switch 95 I tion and thereby causethe device 11 to be actuated, the higher operating potential 75 is'introduced to the coil 47. Continued energizing of the coil 47 with the- -high operating potential 75 would retain the plunger I 53a in the proximate position, but it might also result in overheating of the pilot valve 21. I-Iowever,-as soon as the plunger 53 moves to the proximate position and the push button switch 95is released; the electrical circuit 71 automatically switches the lowe'r. potential 73 to the coil 47 to maintain the plunger 53a'in itslproximate position. The lower potential decreases the amount of current drawn by the electromagnet assembly 41 and significantly reduces the'power-'consumption of the pilot valve 21. Inv the examplegive'n above, the power consumption is reducedseveral-times, as from 320' watts in a singlepilot valve to'about -2 watts. With arevduced current in thecoil 47,,there' isno danger of failure due to overheating. The effective life of the pilot 'valve .21 is substantially increased along with its reli-' ability.

The reduced current is it is realized that-the signal wires 17 which carry the current can be reduced insize. This is of' paramount 79 completes a-circuit through the firstz contact 83 so that the coil 81 is also energized by the lower operating potential 73;through the second'switch 97. This alternate path for energizing the coil81 gives rise'to'the third mode of operation illustrated in FIG. 6. As'soon as pressure is relieved from the push button switch 95 and i-t returns to its normally open position, the second relay 87 is deenergized. and the third and

fourth contacts

91 and 93 return to their normally closed and normally open states, respectively. However, the first relay v79 remains energized through the switch 97 and the first contacts 83 so that the second contacts 85 continue to provide a closed circuit. The lower potential from the source 73 is then introduced through the conthird and

fourth contacts

91, 93 remaining in their closed and open states, respectively. When the push significance when the electricity is transmitted to a re mote location such as the floor of the ocean.

Iclaim: v 1. In apparatus for effecting operation of a fluid actuated device: valve means operatively; connectableto a source of fluid pressure and to the device, said valve means including a valve 'member'shiftable between a first position preventing flow of fluid from the source to the device and a' second position permitting flow of fluid from thesource to the device;'an electrically actutrically actuated means to effect shifting of said valve member from said one position to said other position;

and means for supplying electric power to said electrically actuated means of a second particular value substantially less than said first value toretain saidvalve means in said other position; said electric power of a first value comprising a first source providing a relatively high potential; said electric power of a second value comprising a second source providing a relatively lower potential than said high potential; switching meansfor selectively connecting said first source of a: high potential to said electrically actuated means to.

' means comprises a first relay selectively 'energ izable by especially appreciated when i the lower potential to introduce the higher potential to a the electrically actuated-means, asecond relay connected to thefirst relayand energizable to introduce the lower potential to the electrically actuated means,

' a first normally open switch connect'edto the source of lower potential'and operable to simultaneously energize the first and'second relays so that the lower potential is introduced to the second relay and the high po ated device: valve means operatively connectable to a source of fluid pressure and to the device said valve means including a valve member shiftable between a first position preventing flow of fluid from the source to the deviceand'a second position'permitting flow of fluid from the source to the device; an electrically actuated meansoperatively connected to said valve member for shifting said valve member from on'eof said positions to the other of said positions; means for supplying electric power of afirst particular value to said electrically actuated means to effectshifting of said valve memberfrom said one position to said other position; and means for supplying electric power to said electrically actuated means of a second particular value substantiallyless than said first value to retain said valve means in said other position; wherein said one of said positions is said first position and said'other of said pocloser to said electromagnet; means for supplying elecshifting of said plunger from extended position to proxv sitions issaid second position; said electric power of a first'valu'e comprising a first source providing a relatively high potential; said electric power of a second value comprising a second source providing a relatively lower potential 'than said high potential; switching means for selectively connecting said firstsource of higher potential to said electrically actuated means-to shift said valvemember to said second position or for connecting said second source of lower potential to said electrically actuatedmeans to retain said valve member in said second position; wherein said switching v means comprises'a first'relay selectively energizable by the lower potential to introduce the higher potential to the electrically actuated means, a second'relay connected to the first relay and energizable'to introduce the lower potential to the electrically actuated means,

a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so'that the lower potensitions to the other of said positions,said plunger being shiftable from an extended position spaced from said electromagnet to a proximate position substantially tric power of a first particular value to said coil to effect imate position; and means for supplying electric power to said coil of a secondparticular value substantially less than said first value to retain said plunger in said proximate position; said electric power of a first value comprising a first sourcepro'viding a relatively high potential; saidvelectric power of a second .value comprising a second source providing a relatively lower 'potential than said high potentiah'switching means for selectively connecting said first source of highpotential to said coil to shift said plunger from said extended position to said proximat'eposition or for connecting said second source of lower potential to said 'coilto retain saidvplunger in said proximate position; wherein said switching means comprisesa first relay selectively'energizable by the lower potential to introduce the higher potential to the coil, a second .relay connected to the first relay and energizable to introduce the lower potentialto thecoil, a first normally open switch .connected to the source of lower potential and operable to simultaneously energize the-first and second relaysso that the. lower potential is introduced to the-second relayand the high potential is introduced tothe coil,

and means for continuing current flow from the lower potential through the second and 'first'relays to the coil after the first switch is opened toreduce the power consumed and maintaining the plunger in said proximate position. 3 I I 4. In apparatus for effecting operation of a fluid actuated devicervalve jmeans operatively connected to a source of fluid pressure and to the device, said'valve means including a valve member shiftable between .a first position preventing flow of fluid from thejsource to-the device and a second position permittingflow of fluid from the source to the device; anielectromagn'et .having a coil; a plunger connected to said valve member for shifting said'valve-member, from one of said positions to the other of said positions, said'plunger being shiftable from an extended position spaced'from'said electromagnet'to a proximate position substantially tial is introduced to the second relay and the high potential is introduced to the electrically actuated means, and means for continuing current flow from the lower potential through the second and first'relays to the electrically actuated means after the first switch is opened to reduce the power consumed and maintaining the valvemember in said second position.

3. ln apparatus for effecting-operation of a fluid actuated device: 'valve means operativelyconnected to a source of fluid pressure and to the device, said valve means'including a valve member shiftable between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from the source to thedevice; an electromagnet having a coil; a plunger connected to said valve member for shifting said valve member'from one of said poshifting of said plunger from extendedposition' to proximate position; and means for supplying electric power to said coil of a second particular value substantially less thansaid first value tovretain said plunger in said proximate position; wherein said'one of said positions is said first position and said other of said positions is said second position; said electric power of a first value comprisinga first source providing a relatively high potential; said-electric power of a second value compris-, ing a second source providing a relatively lower potentialthan said high potential; switching means for selectively connecting said first source of high potential to said coil to shift said plunger tosaid proximate position or for connecting said second source of low potential to said coil to retainvsaid plungerin said proximate p0- sition'; said switching means comprising'a first relay selectively energizable by the lower potential tointroduce the higher potential to the coil, a second relay connected to said first relay and energizable to introduce the lower potential to the coil, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the firstand second relays so that the lower potential is introduce to the second relay'and the higher potential is introduced a source of fluid pressure and to the device, said valve means including a valve member shiftable between a first-position preventing'flow of fluid from the source cally actuated means after the first switch is opened -to reduce the power consumedandimaintain the valve member in said other position.

6. In apparatus as defined in claim 5; wherein said one of said positions is said first position and said other I of said positions is said second position.

7. ln apparatus for effecting operatio'n of a fluid actuated device: valve means operatively connected to a source of fluid pressure'and to the device, said valve to the device and a second position permitting flow of 15 fluid from the source to the device; an electrically actuated means operatively connected to said valve member for shifting said valve member from one of said positions to the other of said positions;

a first source providing a relatively high electric potential; asecond source providing a relatively low electric potential;

a first relay selectively energizable by the lower potential to introduce the higher potential to the electrically actuated means, a second relay connected to the first relay and energizable to introduce the lower potential to the electrically actuated means, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduced to the second relay and the high potential is introduced to the electrically actuated means, and means for continuing current flow from the lower potential through the second and first relays to the electrimeans includinga valve member shiftab le between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from; the source-to the device; an electromagnet having a coil; a plunger connected to said valve member for shifting said valve member from one of said positions to the other of said positions, said. plunger being shiftable from and extended position spaced from said electromagnet to a proximate position substantially closer to said electromagnet; a first source providing a relatively high electric potential; a second source pro.- viding a relatively low electric potential; a first relay selectively energizable by the low potential to introduce the higher potential to the coil, a second relay connected to the first relay and energizable to introducethe lower potential to the coil, a firstnormally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduced to the second relay and the high potential is introduced to the coil, and means for continuing current flow from the lower potential through the secondand' first relays to the coil after the first switch is opened to reduce the power consumed and maintaining the plunger in said 7 proximate position. Y

Claims

1. In apparatus for effecting operation of a fluid actuated device: valve means operatively connectable to a source of fluid pressure and to the device, said valve means including a valve member shiftable between a first position preventing flow of fluid from tHe source to the device and a second position permitting flow of fluid from the source to the device; an electrically actuated means operatively connected to said valve member for shifting said valve member from one of said positions to the other of said positions; means for supplying electric power of a first particular value to said electrically actuated means to effect shifting of said valve member from said one position to said other position; and means for supplying electric power to said electrically actuated means of a second particular value substantially less than said first value to retain said valve means in said other position; said electric power of a first value comprising a first source providing a relatively high potential; said electric power of a second value comprising a second source providing a relatively lower potential than said high potential; switching means for selectively connecting said first source of high potential to said electrically actuated means to shift said valve member to said other position or for connecting said second source of lower potential to said electrically actuated means to retain said valve member in said other position; wherein said switching means comprises a first relay selectively energizable by the lower potential to introduce the higher potential to the electrically actuated means, a second relay connected to the first relay and energizable to introduce the lower potential to the electrically actuated means, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduced to the second relay and the high potential is introduced to the electrically actuated means, and means for continuing current flow from the lower potential through the second and first relays to the electrically actuated means after the first switch is opened to reduce the power consumed and maintain the valve member in said other position.

2. In apparatus for effecting operation of a fluid actuated device: valve means operatively connectable to a source of fluid pressure and to the device said valve means including a valve member shiftable between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from the source to the device; an electrically actuated means operatively connected to said valve member for shifting said valve member from one of said positions to the other of said positions; means for supplying electric power of a first particular value to said electrically actuated means to effect shifting of said valve member from said one position to said other position; and means for supplying electric power to said electrically actuated means of a second particular value substantially less than said first value to retain said valve means in said other position; wherein said one of said positions is said first position and said other of said positions is said second position; said electric power of a first value comprising a first source providing a relatively high potential; said electric power of a second value comprising a second source providing a relatively lower potential than said high potential; switching means for selectively connecting said first source of higher potential to said electrically actuated means to shift said valve member to said second position or for connecting said second source of lower potential to said electrically actuated means to retain said valve member in said second position; wherein said switching means comprises a first relay selectively energizable by the lower potential to introduce the higher potential to the electrically actuated means, a second relay connected to the first relay and energizable to introduce the lower potential to the electrically actuated means, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potentiAl is introduced to the second relay and the high potential is introduced to the electrically actuated means, and means for continuing current flow from the lower potential through the second and first relays to the electrically actuated means after the first switch is opened to reduce the power consumed and maintaining the valve member in said second position.

3. In apparatus for effecting operation of a fluid actuated device: valve means operatively connected to a source of fluid pressure and to the device, said valve means including a valve member shiftable between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from the source to the device; an electromagnet having a coil; a plunger connected to said valve member for shifting said valve member from one of said positions to the other of said positions, said plunger being shiftable from an extended position spaced from said electromagnet to a proximate position substantially closer to said electromagnet; means for supplying electric power of a first particular value to said coil to effect shifting of said plunger from extended position to proximate position; and means for supplying electric power to said coil of a second particular value substantially less than said first value to retain said plunger in said proximate position; said electric power of a first value comprising a first source providing a relatively high potential; said electric power of a second value comprising a second source providing a relatively lower potential than said high potential; switching means for selectively connecting said first source of high potential to said coil to shift said plunger from said extended position to said proximate position or for connecting said second source of lower potential to said coil to retain said plunger in said proximate position; wherein said switching means comprises a first relay selectively energizable by the lower potential to introduce the higher potential to the coil, a second relay connected to the first relay and energizable to introduce the lower potential to the coil, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduced to the second relay and the high potential is introduced to the coil, and means for continuing current flow from the lower potential through the second and first relays to the coil after the first switch is opened to reduce the power consumed and maintaining the plunger in said proximate position.

4. In apparatus for effecting operation of a fluid actuated device: valve means operatively connected to a source of fluid pressure and to the device, said valve means including a valve member shiftable between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from the source to the device; an electromagnet having a coil; a plunger connected to said valve member for shifting said valve member from one of said positions to the other of said positions, said plunger being shiftable from an extended position spaced from said electromagnet to a proximate position substantially closer to said electromagnet; means for supplying electric power of a first particular value to said coil to effect shifting of said plunger from extended position to proximate position; and means for supplying electric power to said coil of a second particular value substantially less than said first value to retain said plunger in said proximate position; wherein said one of said positions is said first position and said other of said positions is said second position; said electric power of a first value comprising a first source providing a relatively high potential; said electric power of a second value comprising a second source providing a relatively lower potential than said high potential; switching means for selectively connecting said first source of high potential to said coil to shift said plunger to said proximate position or for connecting said second source of low potential to said coil to retain said plunger in said proximate position; said switching means comprising a first relay selectively energizable by the lower potential to introduce the higher potential to the coil, a second relay connected to said first relay and energizable to introduce the lower potential to the coil, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduce to the second relay and the higher potential is introduced to the coil, and means for continuing current flow from the lower potential through the second and first relays to the coil after the first switch is opened to reduce the power consumed and maintaining the plunger in said proximate position.

5. In an apparatus for controlling operation of a fluid actuated device: Valve means operable connectable to a source of fluid pressure and to the device, said valve means including a valve member shiftable between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from the source to the device; an electrically actuated means operatively connected to said valve member for shifting said valve member from one of said positions to the other of said positions; a first source providing a relatively high electric potential; a second source providing a relatively low electric potential; a first relay selectively energizable by the lower potential to introduce the higher potential to the electrically actuated means, a second relay connected to the first relay and energizable to introduce the lower potential to the electrically actuated means, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduced to the second relay and the high potential is introduced to the electrically actuated means, and means for continuing current flow from the lower potential through the second and first relays to the electrically actuated means after the first switch is opened to reduce the power consumed and maintain the valve member in said other position.

6. In apparatus as defined in claim 5; wherein said one of said positions is said first position and said other of said positions is said second position.

7. In apparatus for effecting operation of a fluid actuated device: valve means operatively connected to a source of fluid pressure and to the device, said valve means including a valve member shiftable between a first position preventing flow of fluid from the source to the device and a second position permitting flow of fluid from the source to the device; an electromagnet having a coil; a plunger connected to said valve member for shifting said valve member from one of said positions to the other of said positions, said plunger being shiftable from and extended position spaced from said electromagnet to a proximate position substantially closer to said electromagnet; a first source providing a relatively high electric potential; a second source providing a relatively low electric potential; a first relay selectively energizable by the low potential to introduce the higher potential to the coil, a second relay connected to the first relay and energizable to introduce the lower potential to the coil, a first normally open switch connected to the source of lower potential and operable to simultaneously energize the first and second relays so that the lower potential is introduced to the second relay and the high potential is introduced to the coil, and means for continuing current flow from the lower potential through the second and first relays to the coil after the first switch is opened to reduce the power consumed and maintaining the plunger in said proximate position.