US2396432A - Control apparatus - Google Patents

Description

Mamh 12, :1946. I G. T. MccLURE 2,396,432

CONTROL APPARATUS Filed 1:58.30, 194s INVENToR Glenn IAlc'Cluz'e MHM ` ATTORNEY Patented Mar. 12, 1946 CONTROL APPARATUS Glenn T. McClure, McKeesport, Pa., assigner to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of 'Pennsylvania Application December 30, 1943, Serial No. 516,204

2 Claims.

This invention relateS to control valve device-s for use in fluid pressure control systems and has particular reference to a relay valve device of the self-lapping type for controlling vthe fluid pressure in such systems.

@ne object yof the invention is to provide an improved relay valve device of theA above type.

yAnother object of the invention is to provide a relay Valve device having means for varying the ratio between the governing force developed by the control pressure and the balancing force developed in the relay valve mechanism.

Another object of the invention is to provide a relay Valve device arranged to be controlled lndividually by uid under pressure or vjointly by fluid under pressure and by manually operative means.

Another object of the invention is to provide a relay valve device arranged to be controlled by iluid under pressure from a remote control station and including means manually operativeifrom a local stationior modifying or varying vthe pressure of fluid supplied bythe device.

A still further object o f the invention is topro` vide a fluid pressure responsive relay valve device embodying a controller, which is adjustable manually to vary the ratio between the control pressure and the controlled'pressure. f

Other objects and advantages will be applrvent from the following more detailed description of the invention.

In lthe accompanying drawing Fig. l is a vertical sectional view of Aa relay valve device embodying the invention; and Fig. 2 isa sectional view of the relay Valve device taken on the line 2--2 of Fig. l.

The adjustable relay valve device yl may cornprise an upper casing section 2 and a lower casing section 3 which are secured together in any suitable manner. The section 3 has an opening at its right hand end -as viewed in Fig. l, Is )vhich opening is closed by an end plateor cap 3a which is rigidly secured in any desired manner to the casing section 3.

Clampedbetween the casing sections 2 and 3 is a pair of laterally spaced exible diaphragme 4 and 5 which are preferably of equal area.

At one side of the diaphragms 4 and 5 there 1s a kchamber 5 which is in constant open communication with the atmosphere 'by way of a passage 8 provided in the end plate 3a. Contained in this chamber is a longitudinally extending control beam or lever 9 which, as will hereinafter more fully appear, is operative tocontrol the operation 0f a self-lapping application and release valve mechanism contained in the upper casing section 2.

One end of the control beam or lever 9 is pivotally connected, by means of a pin l2, to two laterally spaced arms of a link member l3 which link member is rookably mounted by moans of a pin .I4 betweensoaoed :lues t5 and L6, projecties from the end lplate 3o of the casing- Tho lower surface of the control lever or beam 9 is provided intermediate its ends with .a bearing Surfaoo .I8 which ,bears on the central portion I S .of ,a transversely Y,@Xtorlding bor 20 of ,round Cross- Section Iwhich serves as a fulcrum fOr said lever.

The .bar V211 is mountedin .a movable rectangular frame member 2.1 which .is ,contained .in chamber 5 and which may comprise a pair of spaced side pieces 23 and 24 which are joined together at opposite ends by inner .and outer end pieces ,25 and 26, respectively, the bar having its opposite ends mounted in suitable openings provided inthe members ,2:3 and 24y resoootivoly- .The side pieces 2 3 and 24 `of the frame member slidably engage with guide membors'or bosses .Hand 28, rospoo tively, lwhich project inwardly from the opposite side walls of the casing, the yboss 21 in the .present embodiment of the invention being carried by 4a removable casing section or cap 3b and the boss 28 being carried ,by the easing section 3. bosses 2] and 28 besideSguiding the frame member 2l also extend across the Vends of the bar 210 and thus prevent endwise movementl of the b ar relative to the frame member. From the foregoing'description it will -be seen that the -frarne member and bar 12p will be maintained against lateral movement relative to the casing section 3 by the lugs 2l and V28.

Rotatably mounted on the bar 20 are `rollers 29 and 3,0 which are disposed one at each side of the lever 9. These rollers are maintained in place on the bar `by collars 29a and 39a, respectively, which are secured in place on the bay by set screws, `as shown. vThe rollers 2 9 and 3 9 engage and vroll on-a wear plate or track 3l rcarried by the bottom lwall of the casing section 3.

The inner end piece v25 ofthecarriage v 2| ispro.. vided intermediate its length witha stem,3 2 which projects to the exteriorlof the casing through a suitable bore 34 in Van adjusting nut 35 which has screw-threaded connection Ywith the casing section ,3. The -nut 3,5, exteriorly of the casing, is

provided with an enlarged portion 36 having a central bore 31 of greater diameter than the bore 34.

VDisposed in bore y3.1 and slidably mounted on the stem 32 is a spring seat 4 0. This springseat Tho engages a shoulder 4| located at the junction of the bore 34 and counter bore 31, and is maintained against rotary movement relative to the stem 32 by means of a key 44 carried by the spring seat and engaging le side walls of a key way 45 provided in the stem.

Surrounding the stem 32 and interposed between and operatively engaging the spring seat 4D and a collar` 41, carried by the stem is a spring- 49, which collar is held on the stem by means of a lock member 41a which engages the stem. It will here be noted that the spring 49, at all times, urges a collar 59, provided on the inner end piece 25 of the lever 9, into engagement with the outer end 52 of the adjusting nut 35, so 'that rotary movement of the nut will eff ect longitudinal movement of the frame member 2| relative to the control lever or beam 9. Since the bar 20 is carried by the frame member 2| and engages the'bearing surface I8 of the control beam or lever 9, thereby serving as a fulcrum for said lever, it will be obvious that any variation in the position of the frame member relative to the lever will result in variations in the leverage of the control beam or lever 9.

For rotating the nut 35 a handle 55 is provided which handle is rigidly clamped on the enlarged portion 36 of the nut 35, by means of a headed bolt 56 and a nut 51.

Contained in chamber 6 and engaging the lower side of diaphragm 5 is a diaphragm follower 60. This diaphragm follower is provided with a downwardly extending annular boss 6| which is provided with a socket 62 arranged to receive one end of a stem 63. The opposite end of the stem 63 has a convex surface and operatively engages the control beam or lever 9 within a notch 64, having a concave surface, provided adjacent one end of the lever 9.

It will here be noted that the lower end of the stem 63 and the notch 64 are so shaped and arranged as to permit rocking of the lever 9 relative to the stem without danger of causing any binding action between the stem and lever, thus eliminating anyv possibility of unwanted distortion of the diaphragm 5.

At the opposite side of the diaphragm 5 there is a chamber 65 which is in constant open communication with a passage and pipe 66 which may lead to a controlling means (not shown) located at any desired control station, and which may be of any desiredrtype arranged to supply fluid under pressure to and release fluid under pressure from chamber 65 to provide any desired degree of controlling pressure therein.

At the upper face of the diaphragm 4 there is a chamber 68. Contained in this chamber and engaging the upper face of the diaphragm is a diaphragm follower 69. This follower has a stem 10 which is screw-threaded for a portion of its length and which projects through a central opening in the diaphragm and through a central opening in a diaphragm follower 1| contained in chamber 6 and engaging the opposite side Of the diaphragm. A nut 12 provided on the end of the stern 1|J within chamber 6 is tightened against the follower 1| thereby securing the followers 69 and 1| and diaphragm 4 together.

The' upper casing section 2 is provided with an axial bore 13 which is lined with a fixed sleeve like member 14 which is open at its lower end to the pressure chamber 68 located above the diaphragm 4 and which is closed at its upper end by a wall 14a. The upper end of the member is provided with an exterior annular lug 14D which engages a stop shoulder 15 provided in the casing, such engagements insuring the. proper positioning of the sleeve member. Above the chamber 68 and surrounding the sleeve like member 14 is a chamber 16 which is in constant open communication with a fluid pressure control pipe 11 leading to a device (not shown) to be controlled. The chamber 16 is also connected to chamber 68 through a stabilizing choke 18 provided in a Wall 19 of the casing section 2.

The upper face of the diaphragm follower 69 is provided with a central, upwardly projecting hollow stem 80 which extends through a short wear bushing 8| interposed between the stem and a portion of the lower inner wall of the sleeve like member 14. Pressed into the upper and outer end of the stem 80 is a guide member 82 having an enlarged portion 83 which is mounted to slide in the upper and adjacent end of the inner wall of the sleeve like member 14. The guide member 82 is provided with an axial bore 84 which is open at its lower end through a release port in a release valve seat 85 to a chamber 86 in the diaphragm stem 80.

.Above the guide member 82 and within the sleeve like member 14 there is a chamber 88 which is in constant open communication with the chamber 16 by way of passages 89 provided in the sleeve like member 14.

The chamber 88 is connected to a passage 90 leading to a chamber 9| which is in constant open communication with a passage and pipe 92 leading to a source of fluid under pressure (not shown). The chamber 9| is defined by the upper wall 14a of the sleeve like member 14, the casing section 2 and a c'ap or cover member 93 having screw-threaded engagement with the casing section'2. Contained in chamber 9| is a supply valve 94 which is adapted to be operated to control communication through passage 90, which valve is normally held seated, closing communication through passage 90, by means of a spring 95 also contained in chamber 9 I.

'I'he valve 94 is provided with a fluted stem 96 which extends through the passage 90 into chamber 88 where it is provided with a release valve 91 which is so formed and arranged as to cooperate with the release valve seat 85, in a manner hereinafter described, to control communication between chambers B6 and 88.

A stem 99 is provided for operatively connecting the free end of the control lever or beam 9 to the diaphragm 4. This stem, at its lower end engages the free end of the control lever or beam 9 within a notch |00. The stem extends upwardi ly through an axial bore |0| in the diaphragm Assuming the vnut 35 and thereby the frame member 2| of the relay valve device are positoned as shown in the drawing and that the pipe 66 and thereby the chamber 65 above the diaphragm A5 are devoid of fluid under pressure. Under these conditions the several other operating parts of the relay valve device will be in the position in which they are illustrated in the drawing. With the diaphragm stem 8D thus positioned, the release valve seat 85 of the guide member 82 will be out of engagement with the release valve 91, and the spring 95 will maintain the supply valve 94 seated. With the supply valve 94 thus maintained seated, communication between chambers 9! and 88 is closed, and with release valve 91 unseated pipe l'I and connected chambers 16 and 68 are open to the atmosphere past said valve and through chamber 86 in the diaphragm follower stem 80, ports 86a in web I 92, bore IUI in diaphragm follower `b9, chamber 6 and passage 8.

If it is now desired to supply .fluid under pressure .to pipe l?, fluid under pressure is admitted to chamber 95 from a remote control station through pipe and passage 55. Fluid under pressure thus supplied to chamber 65 and acting on diaphragm causes the diaphragm to move or deflect downwardly. The diaphragm 5 as it is thus deflected acts through the medium of diaphragm follower 89 and stem 93, to cause the lever 9 to rock in a clockwise direction about the fulcrum bar E9. The lever 9 as it is .thus rocked shifts the stem 99 upwardly.

Upward movement of the stem 99 causes the diaphragm assemblage including diaphragm 4, diaphragm followers 59 and ll and diaphragm .follower stem 8d to move inthe same direction. Upward movement or the stem 8i) will be relative to the release valve Sil until the release valve Seat 85 provided on the guide member 82 .carried 4by the stem engages the release valve. Movement of the valve seat 85 into engagement with the release valve 91 cuts olf communication between chambers 88 and 89, thus cutting off com- .rnunication between chamber 89 and the atmosphere. Continued clockwise rotation of the lever 9 acting through the medium of the stem 99 and the diaphragm assemblage including diaphragm follower stem 89 will then move the .release valve =9l with thestem 90 and the release valve will act to move the supply valve upwardly against the light biasing force of spring 95. As the supply valve 94 is thus moved upwardly it is moved out Vof engagement with its seat.

When the supply valve 94 is-thus opened, -fluid under pressure will flow from chamber 97| past said valve to chamber 88, and thence through yports 89 to chamber .l5 from whence .it flows to the control pipe .'l'i. Fluid under pressure thus supplied to chamber 'l5 also flows through the stabilizing choke 'E3 to chamber 68 above the diaphragm 4. The stabilizing choke is provided to prevent the .pressure in diaphragm chamber 63 increasing .at a faster rate than the Iincrease in the pressure of .fluid in the control pipe 'l'l.

Thepressure of fluid thus suppliedto chamber G8 acts on the vupper face of diaphragm 4 and when the pressure of fluid in chamber 69 and consequently inthe control pipe 'H becomes suf- -cientto overcome thepressure of fluid in chamber 85 `acting on the beam orrlever-9 through the medium of nexible diaphragm 9,'follower-69, and stem 62, the diaphragm 4 will be caused to ex downwardly. As the diaphragm 4 flexesvdownwardly, the diaphragm .follower stem 89 moves in the same direction7 thereby permitting the spring 95 to seat the supply valve 94, without at the same time unseating the release valveSl. With the supply valve 9d seated, communication between chambers 9! and 88 will be cut off and there will beno .further build up of pressure in chamber and connected chamber 68 consequently the .diaphragm 4, followers 99 and 1I, diaphragm follower stem 89 and lever 9 will come to a stop.

` It will be noted that due to the position of the adjusting screw 35 and thereby the frame member 2l the central portion i9 of the fulcrum bar '29 engages the bearing surface or" the lever.9 substantially intermediate its ends. With the fulcrum bar thus positioned, the lengths of the arms of the lever 9 at opposite sides of the fulcrum bar will be equal and since the diaphragms 4 and 5 are of substantial equal areas it will be obvious that the pressure developed in the chamber 68 abo-ve diaphragm 4 and consequently in the control pipe ll will be substantially equal to the pressure supplied to the diaphragm chamber 6'5 above diaphragm 5.

If it is desired to increase the pressure of iluid in pipe l1, fluid under pressure may again be supplied through pipe and passage 9E to chamber 65 to increase the pressure of fluid therein acting on diaphragm 5. The device will then operate in the same manner as above described to cause a corresponding increase in pressure of fluid in chamber 16 and pipe 'll and also in chamber .68 labove diaphragm 4. It will thus be seen that the pressure of fluid in pipe 'Il can be increased in such increments as desired by the provision of corresponding increments of control pressure in chamber 55, and the maximum degree of pressure may be provided in said pipe by providing a certain maximum pressure of fluid in chamber .65.

If it is now desired to reduce `the pressure of fluid in pipe l?. fluid under pressure is released from chamber 95. When the pressure in chamber Vfili acting on the right hand end of the lever 9 through the medium of .diaphragm 5 .and stem 93 is thus sufficiently reduced with respect to the opposing force of fluid under pressure in chamber ,68 acting on the lopposite end of the lever ,9 through the medium of diaphragm .4, diaphragm vfollowers 69 and H and stem 99, said opposing forces denects diaphragm 4 downwardly causing the lever 9 to rock in a counterclockwise direction about the fulcrum bar 29, As the lever .9 is thus caused to rock counterclockwise abo-ut the bar 29, the diaphragm follower 69 and thereby the stem 89 is moved downwardly. This downward movement of the stem S0 will be relative lto the release valve 9i, since the supply valve 94 carried at the opposite end of the stem 9B .is maintained in engagement with its seat by the pressure of spring 95. As a result, the release valve seat 85 provided on the guide member 82 carried at the end of the stem will move out of sealing engagement with the release valve 9.1

to thereby open communication between chambers S8 and ,86. With communication between chambers 89 and 89 established, viiuid under pressure ows from chamber 98 and connected control pipe 'll and chamber S9 above diaphragm 4 to the atmosphere through the circuit hereinbefore traced. When the pressure of iluid in chamber B8 is thus reduced suihciently with respect to the control iiuid pressure in chamber 65, the latter pressuredeflects.diaphragm downwardly. This downward deflection of the diaphragm 5 causes the lever 9 to rock clockwise about the bar 20 and thus through the medium of the stem 99, moves the diaphragm follower and attached stem 89 upwardly until the release valve sea-t engages the release valve 97. This seating of the release valve 9'! will prevent further flow of fluid under pressure from chambers -88.and.68 and pipe `ll, thereby ,limitingthe reduction in pressure therein to a degree corresponding to the reduction in pressure in the control iluid pressure acting in chamber 65.

If it is desired to effect a further reduction in pressure in pipe 1l', a further reduction in pressure is effected in chamber 65, andthe device will then operate to eiect a corresponding reduction in pressure in said pipe in the same manner as above described. Upon a complete release of fluid under pressure from chamber 65, the diaphragm and the lever 9 will move to and remain in the position in which they are shown in the drawing to allow a complete release of iluid under pressure from pipe It will now be seen that with the frame member 2| disposed as shown in the drawing, i. e., with the fulcrum bar 2|) engaging the lever 9 at a point midway between its ends, the relay valve device is operative in accordance with any desired degree of increase or decrease in the pressure of control uid in chamber 65 to cause corresponding variations in the pressure of uid in pipe 1.1.

It will be understood that the pressure of uid in chamber 63 required to produce the lap action of the supply and release valves may vary with relation to the pressure of iiuid established in chamber 65, as determined by the relative lengths of the lever arms of lever 9.

It will be obvious that if the frame member 2| and thereby the fulcrum bar 20 is moved longitudinally of the lever in a direction away from the stem 63 the arm of the lever to which the diaphragm 5 is connected, will be correspondingly lengthened, so that it will require a greater fluid pressure in chamber 68 to overcome the pressure of fluid in chamber 65- than if the frame member were positioned as shown in the drawing. If, on the other hand, the frame member 2| and thereby the fulcrum bar is moved in the direction toward the stem 63 the effective length of the arm is reduced and as a consequence a lesser pressure in chamber 68 will overcome the pressure of uid in chamber 65 than is required if the frame member is positioned as shown.

In certain control systems it is desirable to control a relay valve device or the like jointly from two different control stations. For instance, on certain airplanes powered by two or more engines it is desirable when the speed of the engines are simultaneously controlled by the pilot, that the engineer be capable of adjusting the speed of one or more of the engines in order to synchronize all of the engines. The relay valve device embodying the invention is particularly adapted for this type of control For example, one of these relay valve devices may be provided at the engineers control station for controlling each en` gine 0n the plane. The pipe 66 may lead to the pilots control station where suitable means may be provided for operation by the pilot to supply uid under pressure -to several pipes 66 simultaneously for thereby effecting operation of the devices to simultaneously adjust the speed of the several engines. If the engineer then nds it necessary to either increase or decrease the speed of any one or more of the engines to bring them into synchronism with the other engine or engines, he rotates the handle either clockwise or counterclockwise, as the case may be, to adjust the position of the frame member 2| and thereby the fulcrum bar 20 relative to the lever 9.

It will be noted that when. the handle 55 is rotated in a clockwise direction the frame member 2| and thereby the fulcrum bar 2|] is moved, through the medium of the screw 35 relative to the lever 9 in a direction toward the right-hand and that rotation of the handle in a counterclockwise direction causes the frame member 2| and thereby the fulcrum bar to move relative to lever 9 in a direction toward the left-hand.

`Movement of the fulcrum bar 20 either to the right or to the left from the position in which it is shown at a time when iiuid under pressure from pipe 66 is effective in chamber 65 and substantially the same pressure of fluid is also effective in pipe 11 -and chambers 68 and 88, causes the device to operate in the same manner as above described to provide in said pipe and chambers 68 and 88 fluid at a pressure determined by the position of the fulcrum bar relative to the end of the lever 9 operative connected to the diaphragm 5. It willbe noted that in this case the pressure of fluid obtained in pipe 11 is regulated by fluid under pressure supplied to chamber and by manual control of the screw 35. The proper adjustment of screw 35 and thereby the fulcrum bar 20 will therefore provide any desired increase or decrease in pressure of fluid in pipe 'l1 relative to that obtained in response to pressure of iiuid supplied to chamber 65.

From the foregoing it will be seen that I have provided an improved relay valve device which is arrangedv to be controlled by fluid under pressure from a remote station and which includes adjustable means manually operative for varying or modifying the pressure supplied by the device.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A control valve device comprising a casing, in combination, valve means in said casing operative for at one time supplying fluid under pressure to a chamber in the casing and operative at another time for venting fluid under pressure from said chamber, a flexible diaphragm mounted in said casing subject to the pressure of uid in said chamber for operating said valve means to vent uid under pressure from said chamber, a rockable lever operatively associated at one end with said ilexible diaphragm and at the opposite end with another flexible diaphragm, a control chamber, said other flexible diaphragm being responsive to an increase in pressure of fluid in said control chamber to rock said lever to effect oper ation of said valve means to provide a corresponding increase in pressure of iluid inthe rst mentioned chamber, the iirst mentioned diaphragm being responsive to the pressure of fluid supplied to the rst mentioned chamber for opposing the rocking movement of said lever, a fulcrum about which said lever rocks, a frame member provided with a stem and arranged to carry said fulcrum, said frame member being shiftable longitudinally of said lever` for varying the leverage ratio of said lever, a member having screwthreaded engagement with said casing and at one end engaging said frame member, means associated with said stem and said member for at all times maintaining said one end of said member in engagement with said frame member, and a handle carried by said member operative to rotate said member for shifting said frame.

2. A control valve device comprising a casing, inV combination, valve means in said casing operative for at one time supplying fluid under pressure to a chamber in the casing and operative at another time for venting uid under pressure from said chamber, a, flexible diaphragm mounted in said casing subject to the pressure of fluid in said chamber for operating said valve means to vent fluid under pressure from said chamber, a rockable lever operatively associated at one end with said flexible diaphragm and at the opposite end with another exible diaphragm, a control chamber, said other flexible diaphragm being responsive to an increase in pressure of fluid in said control chamber to rock said lever to effect operation of said valve means to provide a corresponding increase in pressure of uid in the rst mentioned chamber, the rst mentioned diaphragm being responsive to the pressure of uid supplied to the first mentioned chamber for opposing the rocking movement of said lever, a fulcrum about which said lever rocks, a frame memextension projecting to the exterior of said casing through said member, spring means cooperating with said extension and said member for maintaining said member in engagement with said frame member, and a handle carried by said member operative to rotate said member for shifting said frame member.

GLENN T. MCCLURE.

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