USRE22455E

USRE22455E - Valve

Info

Publication number: USRE22455E
Authority: US
Publication date: 1944-03-14

Description

2 Sheets-Sheet 1 l Z l, zo"

l! E I INVENTOR n 0 .w W e. .w W

n I vill!" I han:

... hl; f/

lilllllllllIIII-Illll-l n nllllr i March 14, 1944. w. G. wlLsoN Re 22,455

VALVE l Original Filed Jan. 31. 1941 2 Sheets-Sheet 2 A IHIHY H L: ZZ E Z5] 76' .31' fa' 24 M Jf WWIMMERNEI Ressued Mar. 14, i944 VALVE Wylie G. Wilson, Elisabeth, N. J., assignor to Everlasting valve Company, Jersey City, N. J.. a corporation of New Jersey K Original No. 2,330,020,v dated September 2l, 1943.

Serial No. 376,719, January 31, 1941. Application for reissue January 17, 1944, Serial No.

Claims.

This invention -relates to improvements in valves and more particularly to improvements in valves of the type known to the art as plug cock valves.

An object of .the present invention is to provide a valve structure and operating mechanism of such character that continuous movement of an operating member in a selected direction causes axial movement of the plug, rotation thereof and then reverse axial movement.

Another object of the invention is to provide mechanism for a valve of the character before described. which operating mechanism is so constructed that initial axial movement of the plug is accomplished without rotary movement thereof, rotary movement of the plug is accompanied by slight axial movement thereof in both directions andthen following the rotary movement, accelerated reverse axial movement of the plug is accomplished without rotary movement thereon Another object of the invention is to provide operating mechanism of such character that initial axial movement of the plug is accomplished at an accelerated rate without rotary movement of the plus, rotary movement is accomplished yin accompaniment with a slight increment of axial movement in the same direction and then with a slight reverse axial movement of the plug and finally the plug is moved in reverse axial direction at an accelerated rate.

A further object of the invention is to provide valve operating mechanism of such character that rotation of a crank like member in a single direction causes axial movement of the plug in one direction and then reverse axial movement thereof.

A further object of the invention is to provide operating mechanism as just described in which means are provided for rotatingthe plug during a part of the time the plug is/inoving axially in each direction.

A still further object of the invention is to provide in combination with operating mechanism as Just described, a pinion and gear arrangement intermittently operated for causing rotation of In carrying out the foregoing and other objects of the invention, use is made of a plug cock valve l made up of a casing and a plug member therein.

which plug member has a' through opening adapted to be aligned with the openings in the valve casing. In the drawings the plug is illustrated as being a tapered plug whichl would be the customary form. The plug has a stem passing through a sleeve in such fashion that the stem is free to rotate relative to the sleeve but is so held therein that relative axial movement be tween the stem and the sleeve is prevented. The sleeve is threaded into a second sleeve member, which in turn is threaded into a part of the supporting vstructure of the valve framework but which second sleeve is normally held 4 against movement of any character. Consequently, rotation of the first sleeve in one direction will cause axial movement o f the stem in one direction while ya rotation of' this same sleeve in the opposite direction will cause reverse axial movement of the stem. The second sleeve is providedfor adjusting the relative position of the first sleeve and consequently of the stem and plug so that the plug can be properly seated in the valve body with its opening in proper relation to the openings in such body, in the case of a valve with a parallel-walled bore, and the proper seating of the plug in the body in the case of a tapered plug and bore.

Rotary movement of the first sleeve is accomplished through the agency of a connecting rod secured at one end to an extension of the sleeve and at the other end to a crank member. This crank member in turn is secured to an operating shaft whereby rotation of the operating shaft will cause such movement of the \crank as to rotate `the sleeve, first in one direction and thenv in the opposite direction. In conjunction with the connecting rod arrangement-just described, the valve stem has a mutilated gear or gear sector at the upper end thereof which is adapted to be engaged by a pinion also in the form of a mutilated gear or gear sector, the engagement being carried out intermediate the ends of the cycle of movement of the operating shaft so that meshing of the pinion and the gear on the stem and consequent movement of these parts will cause rotation of the stem and of the plug. I'he various parts are so related that initial movement of the operating shaft causes a relatively rapid axial movement of the stem through a part of the cycle of movement of the operating shaft; then causes the rotation of the plug accompanied first by an increment of axial movement of the stem in the same direction and then by a slight reverseaxial movement of the same; and finally the reverse axial movement l of the stem is at an accelerated rate corresponding to the rate of initial axial movement and uriaccompanied by any rotation or the stem.

Other features, objects and advantages of the invention will become apparent by reference to the following detailed description of the accompanying drawings wherein Fig. 1 is a vertical section of avalve structure embodying the invention:

Fig. 2 is a side elevation of the same structure viewed at right angles to the sectional showing of Fig. l:

Fig. 2a is a view of fa wrench utilized for aljusting the position of the plug in the body of the valve:

Fig. 3 is a plan view oi the structure shown in Figs. 1 and 2;

Fig. 4 is a section taken substantially on the line l--I of Fig. 3;

Fig. 5 is a section taken substantially on the line 5-8 of I'lg. 3;..

Flg. 6 is a diagram showing the relative positions of parts of the valve operating mechanism during the cycle oi' operation thereof, and

Figs. 'l to 11 inclusive are diagrammatic illustrations of some of the operating parts oi' the mechanism during a complete cycle of operation thereof, the parts being shown in progressively changed positions.

ferring now to the drawings and particularly to Figs. l and 2, Il indicates generally a body of a valve of the usual plug cock type. This body has openings Il and I2 therein to which conductors can be secured for the passage of matter to be controlled by the valve. The body of the valve is so shaped interiorly as to provide a seat for the usual plug member Il which has a port iii therein ot size and shape to match the ports lia in the valve body. In addition the lower end of the plug may be provided with a stub stem member II seated in the proper recess i1 in the valve body for the Purpose-0f aiding in centering the plug, but such construction may be omitted if desired. A cover i8 o! conventional character is secured to the valve body with an interposed gasket il in customary fashion and this cover is centrally apertured for the passage oi' a valve stem 2li. A stuiiing box for the reception of packing Il is provided in the cover and a packing compressor 22 is threaded into the box in the usual manner.

Secured to the cover Il by means of shoulder studs Il is a plate 2l utilised in supporting the operating mechanism comprised in this invention. Above the packing compressor 2! the stem Il is provided with a portion il of slightly reduced diameter around which portion nts a sleeve member 2t. The lower end of this sleeve member contacts the shoulder on the stem formed by the two parts oi' different diameters. The sleeve Iris retained on the stem against andai movement relative thereto by amutilated 4gearorgearsectorIllreyedontheupperendof the stem and resting on a step provided thereon. The gear 21 will be described in detail later. It issecuredtothe stemandisiurtherheldonthe stemby anut 2l screw threaded ontotheupper end of the stem. Since the sleeve Il is coniined between shoulder formations, i. e., the lower step onthestemandthe memberILitisx-estrained against axial movement relative to the stem but is free to rotate relative thereto.

'nieu portion or the sleeve n is externany threaded as at 2l to engage similar threads provided in the inner wall of a second sleeve 3U,

part of the plate 2l.

.which second sleeve in turn is externally threaded to nt the threads in the wall oi an aperture in the plate Il.

The upper end of the second or adjusting sleeve 3l is provided with a ilange in which teeth 3l (Fig. 3) are cut. Cooperating with the teeth 3| is a dog member l2 mounted ona fulcrum pin 3| secured to the plate 25. The dog 32 has a tongue 38 so shaped as to ilt in a recess between any of the respective teeth Il on the adjusting sleeve. This dog 32 can be moved from the full line position o! Fig. 3 in which the tongue 38 is in engagement with the adjusting sleeve Il to the dotted line position of the same figure in `which this sleeve is released. Matched through openings are provided in the dog I2 and the plate 2l in such position that a cotter pin 31 (which can be split as shown) can be passed through these openings and, if the pin is split, the lower end can be spread, either forcibly or naturally, when the dog is in the locking or full line position of Fig. 3.

The purpose of this adjusting sleeve 30 is to l obviate the necessity for extreme accuracy of machining of the various parts of the valve so that these parts can be properly oriented and seated by manipulation ot this adjusting sleeve. For example, fthe plug il can be turned to the open position permitting passage of iluid through the valve and when in such position it can be firmly seated by rotating the adjusting sleeve lil in the suitable direction to cause a downward movement oi' the sleeve 2l and consequentlyy of the stem 2U. Rotation of the adjusting sleeve can be carried out by any operator by engaging a spannerwrench S with the teeth oi' the adjusting sleeve and by manipulating this wrench, which rotates the sleeve in the desired fashion. When the plug has been ilrmly seated in the tapered recess Vin the valve body, the adjusting sleeve 'can be locked by moving the dog 32 into its locking position, in which position it is secured against movement by use oi a split cotter pin in the manner shownl or in any other desirable fashion.

The sleeve 26 is provided with two outwardly extending lugs 4I through which extends a pin l2 utilized for securing one end of a connecting rod M inposition between bosses Il. I'he lugs are spaced apart a distance greater than the thickness of the connecting rod so that, as the lugs along with the sleeve 26 rotate with combined axial movement, relative sliding movement between the connecting rod (which does not move axially) and the pin l2 is permitted. The other end ofthe connecting rod M has a crank pin I5 extending therethrough and the connecting rod ll on the lower end oi' an operating shaft," which is Journalled in a bearing Il formed as The upper end of the operating shait Il has a mutilated gear or gear sector il keyed thereon and retained by means of a handle Il fast on shaft 4I and retained in place against axial movement by a nut l2 threaded on to the upper end ot the shaft 43. Boththehandleandthegearsector Ill areso secured to the operating shaft Il that these parts must rotate as a unit.

Thegearsectororpinionlllhasteeth Il formedthereonasshowninl'ig.2andsuchteeth extend through relatively small sector o! the gear. Likewise the gear sector 21 on the stem 2l has teeth l5 thereon extending through a sector of approximately 90 thereof. The mem-- ber 21 also has locking

formations

56 and 51 adjacent the ends of the teeth I5, which locking formations can engage with the lower periphery Il of the pinion 5l. The part is spaced axially from the teeth 55 to prevent contact between these parts when the gear 21 moves axially.

The operation and use of this device is substantially as follows: for purposes oi' illustration reference may be made to Fig. 6 wherein the arc A represents the path of movement oi the center of the pin l2 to which one end of the connecting rod 44 is pivotally secured. The point B represents the axis oi the valve stem; the point C represents the position of pin 42 when the plug is in its seated condition and the points D and E represent points in the travel of this pin. The polnt'F represents the axis of the operating shaft 8 while the points G, H, I, J, and K represent points in the travel of the axis of the crank pin 45. The lines connecting the various points C, D, E, G, H, I, J and K represent the connection between the

pins

42 and 45, i. e., the connecting rod 4I.

Assuming that the valve is closed, in which condition the plug is ilrmly seated, a cycle of operation to open the valve requires a movement of the operating handle 5i through approximately 270. Such movement of the handle causes a movement of the crank pin 45 from the point G to the point K. During the rst 90 of movement of the operating handle andA consequently of the crank pin l5, the sleeve pin I2 is moved through an arc from the position C to the position D, which movement causes a rotation to that extent of the sleeve 26. Such rotation of the sleeve 26 in the stationary sleeve 30 imparts axial movement to the valve stem 20 and such axial movement is at a relatively rapid rate and causes the the teeth 5l of the gear 21 and this latter gear is locked in, place by contact betweenthe iormation l and the periphery Il of the pinion I0. y

When the operating handle or lever Il has moved through the initial 90 o! movement of the crank pin 4l, the operating parts assume the Fig. 8 position in which the teeth Il of the pinion are just coming into mesh with the teeth l of the gear 21. 'This Fis. 8 position shows the connecting rod in position extending from point D to p point H. During such 90 o1' movement the sleeve plug to be lifted appreciably. At the beginning of the second 90`of movement, or in other words movement of the crank pin from the position H, the movement of the sleeve pin from the position D toward the position E is greatly retarded and causes only a slight increment of axial movement up to the point E of the sleeve pin at which time the connecting rod is in what may be called dead center position. Continued movement through this second arc of 90 caus'es a reverse movement of the sleeve pin from the position E toward the position D at the same rate of movement as is accomplished in the movement from i position D to position E. During the last 90 Yci movement of the crank pin from position J to position K, the reverse axial movement of the valve stem is Iaccomplished at an accelerated rat-e as indicated by the diagrammatic showing of movement of the ysleeve pin from position D to position C. During the second 90 of movement of the crank pin rotation of the valve stem is also carried out inY a manner to be immediately described.

Bearing in mind then the schematic showing of the operation of the mechanism, reference is now made to Figs. 7 to l1 inclusive, which figures illustrate five positions of the operating mechanism during the movement of the 'valve from closed position to open position. In Fig. 7 the connecting rod 44 is shown in the same angular relation .as in Fig.y 6, that is with this rod extending from the point C to the point G. In this position the teeth 54 of the pinion 50 are out of mesh with 2l has been rotated through the major part of its arc of movement causing a relatively rapid upward movement of the valve stem and consequently of the plug to unseat the plug. During the next 45? of movement of the crank pin, that is from the Fig. 8 to the Fig. 9 position, the sleeve pin l2 completes its arc of movement which is a relatively small arc as compared to the initial arc of movement consequently causing an increment of further axial movement of the plug in the same direction. At the same time the engagement of the teeth on thei pinion with the teeth on the gear 21 causes rotation of the stem 20 and consequently oi' the plug Il. The Fig. 9 position shows the relation of the parts when the connecting rod is at dead center and at such position which is of a momentary character in the cycle oi' operation, the plug is stationary so far as' axial movement is concerned so that any continued movement of the crank pin in the same direction starts the connecting rod to move in the reverse direction so far as the sleeve pin to which the connecting rod is secured is concerned. Consequently, atlurther 45 of movement shifts the connecting rod and the remaining parts from the Fig. 9 to the Fig. 10 position, in which latter iigure the connecting rod assumes the position from the point D to the point J. At this time the teeth 5I move out of engagement with the teeth 55 and the gear 21 is locked by contact between the formation 51 and the periphery 58 of the pinion.

Thus in this second 45 movement the valve stem and plug are moved downwardly in unison at a relatively slow rate yat substantially the same rate of movement in reverse order as that causing the before-mentioned increment of movement. The plug now being in open position the mechanism continues to operate to reseat the same, or in other words the mechanism is moved from the Fig. 10 to the Fig. ll position, a position in which the connecting rod extends from the point C to the point K. Rotation during this movement is prevented by the lock between the pinion and gear 21 before described so that the only movement of the plug is an initially accelerated and then slightly retarded downward scribed for opening the valve.

While the operating mechanism has been described as including the adjusting sleeve 30, it is to be understood that such sleeve can be omitted, in which event the sleeve 26 will be threaded directly into an aperture in the plate 25. However, as beforepointed oui-...use of the sleeve 2li with the cooperating locking mechanism therefor presents advantages since such sleeve eliminates the necessity for microscopic accuracy in machining the parte to permit proper orientation Y thereof for eiilcient operation. The plug can be positioned in a desired relation to the body of the valve and then adjusting sleeve 3l can be ad- Justed in the manner previously described while the plug is held against rotation by holding the operating handle or lever Il. Thus, in selected positions oi the plug. proper seating thereof can be obtained by preliminary adiustment of the sleeve 3l, which adjustment can be accomplished without` disturbing the function of any oi the remaining parts oi the mechanism. The lockin arrangement hereinbefore described special merit in that the cooperation ci the dog with the teeth 3l is oi' such nature that the sleeve Ill can be positively locked against rotation in either direction once it has been adjusted to the desired position. The tongue Il of the dog can be moved into the space between two teeth and due to the shape o! the teeth and of the tongue, when in this position, the sleeve Il cannot be turned in either direction. Also since simplied retaining means are used for holding the dog in tooth-engaging position, it follows that the diiiicuities which might be attendant upon the use of springs or other mechanism for holding the dog in engagement with the teeth are obviated. With the arrangement shown it is possible to move the dog out of tooth-engaging position and then adjust the sleeve as desired while the dog remains outof the way, in which position it is not to hold the same against the action of a spring or any other mechanism.

Furthermore. the teeth serve two purposes. Due to the fact that they are oi' such shape as to be held against movement in either direction by a simple member such as the tongue oi the dog, it is possible to make use o! a spanner wrench to move the sleeve in either direction ior the purpose of obtaining exact adjustment o! the sleeve. Also in actual practice, the number of teeth are so related to the pitch of the exterior thread on the sleeve It that the axial movement due to a circumferential movement in an are oi' one tooth is less than the minimum ammt of adjustment ever desirable between body and plug. Consequently, extremely iine adjushnent can be readily obtained.

The operating lever or handle li has been illustrated as being in the nature of a handle which conveniently is so locked to the operating shaft' as to be lined up with the line oi' travel of fluid through the valve in the open position thereof. 'I'his lever, as shown, moves in one horirontal plane, or in other words. in a single plane at right angles to the axis o! the valve stem. However, as will be apparent to thou skilled in the art, such handle or lever could have substituted therefor a hand wheel. a chain wheel for overhead operation, an electric motor or a power cylinder, all o! conventional character.

While the adjusting mechanism previously described is of advantage in connection with properly orienting a plug relative to the body'o! the valve and for assuring proper seating of the plug, still the operating mechanism is capable of compensating for ordinary slight wear without requiring adjustment of the adjusting mechanism. For ordinary purposes such slight wear can be compensated for by merely moving the operating mechanism further in either the opening or closing direction-which movemenhin the case oi' a tapered plug, will cause the plug to'seat itsans seliinataperedborewithoutchangingthe proper' relation oi the portsin the plug with the ports in the body when these ports are in open position. y

Though the operating mechanism has been described herein principally in connection with valves utilizing a tapered plug, it will be evident that this operating mechanism can be used with valves ot other construction and accordingly the invention is to be so considered.

From the foregoing itnwill be seen that the present invention provides new, simple and eiiicient mechanism for operating a plug cock valve in such fashion that the valve can be moved from open to closed position. or vice versa, without the damaging friction and the like which is normally attendant upon such operation in a valve in which axial movement is not imparted to the plug prior to rotary movement thereof. The mechanism herein described is of the utmost simplicity and permits sequential operation of the character desired through the agency o! a single operating member moving continuously in a selected direction. It willv be apparent that modification can be made in the disclosed mechanism, in view o! which any limitations imposed thereupon are to be only those set forth in following claims.

What is claimed is:

1. A valve of the type described comprising a casing, a stern for said valve extending from said casing, an operating member, a sleeve member surrounding said stem and movable to impart axial movement only to said stem, a crank rotated by said operating member, a connecting rod between said crank and said sleeve, and a pair oi' gear sectors connecting said operating members and said stem, said crank and said gear sectors being so coordinated that selected unidirectional movement ot the' operating member causes axial movement ot the stem. nrst in one direction and then in reverse direction and rotation of the stem-during the nnal stage of axial movement in one direction and the initial stage of axial movement in the reverse direction.

2. A valve of the type described comprising a casing, a stem for said valve extending from said casing, a supporting member above said casing, and a pair of sleeves. one threaded into the other, the innermost sleeve surrounding said stem and limiting said stem to rotation only relative to the sleeve, the puter. of said sleeves being in threadedengagement with said supporting member whereby rotation of the outer sleeve causes axial movement of said stem for adjustment of said stem relative to said casing.

3. A valve of the type described comprising a casing. a stem for said valve extending from said casing. a supporting member above said casing, a pair of sleeves, one threaded into the other, the

innermost sleeve surroimding said stem and limiting said stem to rotation only relative to the sleeve, the outer of said sleeves being in threaded locking said outer sleeve in any adjusted position thereof.

4. A valve ofthe type described comprising a Sil-lg, a stem for said valve extending from said casing, a supporting member above said casing. a pair of sleeves, one ed into the other, the innermost sleeve ding said stem and limaaess iting said. stem to rotation only relative to the sleeve, the outer of said sleeves being in threaded engagement with said supporting member whereby rotation ot the outer sleeve causes axial movement or said stern for adjustment of said stem relative to said casing, a toothed liange on said l outer sleeve and means supported by said supporting member and engageable with the teeth ot said ilange tor locking the outer sleeve in any adjusted position thereof.

5. A valve of thetype described comprising a casing. a stem for said valve extending from said casing, a supporting member above said casing, a pair o! sleeves. one threaded into the other, the innermost sleeve surrounding said stem and limiting said stem to rotation only relative to the sleeve, the outer of said sleeves being in threaded engagement with said supporting member whereby rotation oi' the outer sleeve causes axial movement of said stem for adjustment ot said stem relative to said casing, a toothed ilange on said outer sleeve, and a dog pivoted to said supporting member and movable to engage said toothed ange to lock said outer sleeve in any adjusted position thereof.

6. A valve or the type described comprising a casing, a stem i'or said valve extending from said casing, a supporting member above said casing, a pair of sleeves, one threaded into the other, the innermost sleeve surrounding said stem and limiting said stem to rotation only relative tothe sleeve, the outer ot said sleeves being in threaded engagement with said supporting member whereby rotation of the outer sleeve causes axial movement of said stem.for adjustment of said stem relative to said.casing, a toothed flange on said outer sleeve, and a dog pivoted to said supporting member and movable to engage said toothed ilange to lock said outer sleeve in any adjusted position thereof, said dog and said supporting member being provided with apertures aligned when the dog is in toothed iiange engaging position for the passage oi a locking member through the apertures.

7. A valve oi the type described comprising a casing, a stem for saidA valve extending from said casing, a supporting member above said casing, a pair of sleeves, one threaded into the other, the innermost sleeve surrounding said stem and limiting said stem to rotation only relative to the sleeve, the outer of said sleeves being in threaded engagement with said supporting member where- 'by rotation oi the outer sleeve causes axial movement. of said stem for adjustment of said stem relative to'said casing, a toothed flange on said outer sleeve, and a dog pivoted to said supporting member for engagement with said toothed ilange to lock mid outer sleeve in adjusted positions, the teeth of said flange and the pitch of the external thread of the outer sleeve being so lrelated that rotation of the flange and sleeve through an arc of one tooth causes a predetermined axial movement of the sleeve.

8. A valve of the type described comprising a casing, a stem for said Valve extending from said casing, a supporting member above said casing, a pair of sleeves, one threaded into the other, the innermost sleeve surrounding said stem and limiting said stem to rotation only relative to the sleeve, the outer of said sleeves being in threaded engagement with said supporting member whereby rotation of the outer sleeve causes axial movement of said stem for adjustment oi said stem relative to said casing, a toothed flange on said outer sleeve, and a dog pivoted to said supporting member i'or engagement with said toothed flange to lock said outer sleeve in adiusted positions, the teeth oi said flange and the pitch oi' the external threadottheoutersleevebein'gsorelstedthat rotation to the nange and sleeve through an arc or one tooth causes a predetermined axial movement of the sleeve, and means ior locking said dog in tooth engaging position.

9. A valve of the type described comprising a casing, a stem for said valve extending from said casing, a supporting member above said casing, a pair of sleeves. one threaded into the other, the innermost sleeve surrounding said stem and limiting said stem to rotation only relative to the sleeve, the outer of said sleeves being in threaded engagement with said supporting member whereby rotation ot the outer sleeve causes axial movement of said stem for adjustment of said stem relative to said casing, a toothed :lange on said outer sleeve, and a dog pivoted to said supporting member for engagement with said toothed flange to lock said outer sleeve in adjusted positions, the teeth oi said ange and the pitch of the external thread of the outer sleeve being so related that rotation o! the flange and sleeve through an arc oi' one tooth causes a predetermined axial movement of the sleeve, said dog and said supporting member being provided with through openings, said openings being aligned when the dog is in tooth engaging position for the passage of a dog locking member through the openings.

10. A valve ot the type described comprising a casing, a stem for said valve extending from said casing, an operating member, a sleeve member surrounding said stem and movable to impart axial movment onlyito said stem, a crank rotated by said operating member, a connecting rod between said crank and said sleeve, and a pair of gear sectors conneotingsaid operating member 'and said stem, said crank and said gear sectors being so coordinated that selected unidirectional movement of the operating member causes axial movement oi the stem, iirst in one direction and then in reverse direction, and rotation of the stem during the iinal stage of axial movement in one direction and the initial stage of axial movement in the reverse direction, and means for varying the operating range of said crank and connecting rod.

11. A valve of the type'described comprising a casing, a stem for said valve extending from said casing, an op'erating member, a sleeve member surrounding said stem and movable to impart axial movement only to said stem, a crank rotated by said operating member, a connecting rod between said crank and said sleeve, and a pair of gear sectors connecting said operating member and said stm, said crank and said gear sectors being so coordinated that selected unidirectional movement oi the operating member causes axial movement of the stem, rst in one direction and then in reverse direction, and

.rotation of the stem during the mm1 stage of axial movement in one direction and the initial stage of axial movement in the reverse direction, and means for limiting the travel of axial movement of the stem in one direction to a lesser degree than could be accomplished by the full part axial movement only to said stem. a crank rotated by said operating member, a connecting rod between said crank and said sleeve. and a pair of gear sectors connecting said operating member and said stem, said crank and said gear sectors being so coordinated that selected unidirectional movement of the operating member causes axial movement of the stem, first in one direction and then in reverse direction. and rotation of the stem during the final stage of axial movement in one direction and the initial stage of axial movement in the reverse direction. said crank and connecting rod having an operating range to move said sleeve through a predetermined are. andmeans for shortening the path of movement of said sleeve through said arc in one direction.

i3. Operating means for a shaft adapted to be moved in a straight line a predetermined distance in forward and reverse directions and rotated through a predetermined arc intermediate the initiation and completion of axial movement. said means comprising a rotatable member spaced from said shaft and having a crank thereon, a collar member surrounding said shaft in such fashion that rotation of the collar member causes axial movement of the shaft; a connecting rod between saidl collar member and said crank. and a driving connection between said shaft and said rotatable member. said crank and connecting rod connections and said driving connection being so related to said shaft that rotation of said driving member at a uniform rate causes axial movement of said shaft at constantly varying speed and rotation of said shaft at a uniform rate intermediate initiation and' completion of the axial movement.

14. A mechanism for imparting movement to a shaft comprising a support apertured for the passage of a shaft. a rotary member mounted in said aperture to axially move said shaft. a rotatable driving member having a crank, a connecting rod between the crank and the rotary member. and gear sectors on said shaft and said driving member, rotation of said driving member causing axial movement of the shaft in successive opposite directions, said gear sectors being so coordinated as to mesh intermediate the initiation and cessation of axial movement of the shaft to rotate the shaft.

15. A mechanism for imparting movement to a shaft comprising a support apertured for the pasage of a shaft. a rotary member mounted in said aperture to axially move said shaft, a rotatable driving member having a crank, -a connecting rod between the crank and the rotary member, and gear sectors on said shaft and said driving member, rotation of said driving member rotating said rotary member through an arc causing axial movement of the shaft ln successive opposite directions, said gear sectors being so coordinated as to mesh intermediate the initiation and cessation of axial movement of the shaft to rotate the shaft, and means for varying the length of the are of rotation of said rotary member.

. WYLIE G. WILSON.