Drawback Sleeve Slide Valve

Abstract

A drawback slide valve for liquid charging apparatus which delivers a measured quantity of liquid into a container. The drawback slide valve has a hollow spindle with two sections of different external diameters. The spindle has two lateral openings in the spindle which communicate with the bore or hollow interior of the spindle. The bore is closed by a plug between the lateral openings. The spindle is partially enclosed by a sleeve which is slidable on the spindle. The sleeve has different diameters at different portions thereof which mate with the different diameters of the two spindle sections. The sleeve also forms an annular chamber having a diameter exceeding that of the larger spindle section and extending between the lateral openings of the spindle. In a first position of the sleeve relative to the spindle, the annular chamber forms a passageway between the two lateral openings of the spindle to permit a flow of liquid through the spindle, and in a second position of the sleeve, the sleeve blocks the upper lateral opening to block the flow of liquid through the spindle. The upper or upstream lateral opening is located on the larger diameter section of the spindle so that when the sleeve is shifted toward the second position to block the upstream opening, the available volume of the chamber between the sleeve and the spindle expands to create a negative pressure therein. The volume of the chamber is increased because the sleeve chamber is moved more along the smaller diameter section of the spindle. With the diameter smaller, the chamber between the sleeve and the spindle increases in volume. The negative pressure due to the increasing volume and blocked entrance opening to the chamber functions to draw back liquid from the downstream lateral opening into the chamber and thereby prevent any drip from the valve after cut-off of the flow of liquid at the upstream lateral opening of the spindle.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

A drawback slide valve which, when moved to cut-off position, pulls back liquid into the valve so as to prevent dripping of any liquid from the discharge orifice of the valve.

2. Description of the Prior Art

This invention relates to valves and relates, more particularly, to a drawback slide sleeve valve for delivering a liquid in a fashion such that when it halts flow of a liquid from the valve, there is no subsequent drip from a discharge orifice. The valve may be used with liquid charging apparatus designed to discharge any one of a variety of liquids, whether into a container or not. When used in conjunction with an apparatus for charging containers, it is ideally suited to filling bottles, ampules, jars or the like. The containers may be filled accurately with liquids such as water, flowable chemicals, honey, creams, syrups, pastes or flowable powders. It will be understood from the foregoing that the term "liquid" as used herein embraces any non-gaseous flowable material.

One of the many difficulties existing heretofore with respect to valves used in conjunction with filling or charging apparatus was the excess liquid which dripped from the orifice of the filling nozzle subsequent to completion of the filling operation. This occurred notwithstanding the prompt cut-off of the liquid to the nozzle by means of a suitable measuring unit. Despite the prompt cut-off, a drop or two, or more, of accumulated liquid tended to fall from the nozzle. The reason for this past cut-off drip was that at least some of the liquid tended to accumulate at the nozzle orifice and coalesce into an overheavy mass from which portions detached themselves under the influence of gravity. Horizontal and vertical movement of the nozzle, as part of the operating cycle in the liquid charging apparatus, encouraged this difficulty because of the inertial forces caused by starting or stopping movement of the nozzle. Moreover, since as often was the case the nozzle was connected by a flexible feed tube to a metering device, there occurred an unwanted discharge of liquid from the nozzle when the tube was bent and its internal volume accordingly reduced. Such discharge of liquid was undesirable from the point of accuracy of fill and of economy where the liquid to be charged into the container was costly. Such liquid discharge was also undesirable from the standpoint of precision where the liquid dosage was potent or for medical purposes. This post terminal discharge is a further nuisance in that it also dirties the apparatus and containers to be filled, and, if allowed to accumulate and harden, interferes with proper operation of the apparatus. More troublesome is the viscous liquid which will not cut off evenly and thus strings out from the discharge orifice thereby necessitating cleaning the filling machine, the nozzle orifice or exposed portions of the container. The cleaning procedures cause additional expense and production slowdown.

Various suggestions have been made to overcome the aforementioned drawbacks. For instance, anti-drip devices have been proposed that included metering cut-offs, sub-atmospheric liquid pullbacks and foot valves. None of these proposed devices have, however, been very successful. The metering cut-offs still allowed liquid drops to accumulate at and around the discharge orifice of the nozzle. Sub-atmospheric liquid pressure applicators, by reducing the pressure in the feed tube, tended to pull remnant liquid back into the discharge nozzle and even into the feed tube. However, these applicators were costly and bulky, required additional equipment (e.g., suction pump, additional tubing and valves) and added considerable overhead to the production costs as well as upkeep of the filling apparatus. Foot valves (valves at the outflow terminals of filling nozzles) in general, have thus far, except for the structure shown, described, and claimed in U.S. Pat. No. 3,205,920 issued Sept. 14, 1965, been ineffectual because they permitted liquid to flow over a surface which was exposed after the valve was closed and this liquid accumulated on the exterior of the valve from where it would drip or shake off when the nozzle started and stopped during the operating cycle of the liquid charging apparatus.

SUMMARY OF THE INVENTION

One of the principal objects of the present invention is to avoid the aforedescribed drawbacks of the prior art.

It is another object of the invention to provide an apparatus of the character described having an anti-drip device in the form of drawback sleeve valve, which minimizes accumulation of liquid on the exterior surface of the discharge nozzle.

It is still another object of the invention to provide a drawback sleeve valve which is simple and positive in operation and yet requires very little maintenance.

It is yet a further object of the invention to provide a drawback sleeve valve which consists of relatively few parts and is inexpensive to make and use.

It is another object of the invention to provide an anti-drip device which requires no auxiliary pump or additional tubing.

It is another object of the invention to provide a drawback sleeve valve that will cut off cleanly and sharply the final portion of the discharge and which is particularly useful in connection with viscous fluids since it is thereby able to prevent the formation of hanging strings.

Further objects and advantages of the invention will be set forth in part in the following specification and in part will be obvious therefrom without being specifically referred to. With the above and other objects of the invention in view, the invention consists in the novel construction, arrangement, and combination of various devices, elements and parts, as set forth in the claims hereof one embodiment of the same being illustrated in the accompanying drawings and described in the specification.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description, taken in connection with the accompanying drawings, in which:

FIG. 1 is a fragmentary elevational view of a multiple line filler which includes a group of filling nozzles that have anti-drip devices constructed in accordance with the present invention;

FIG. 2 is an enlarged vertical partially sectional view through one of the anti-drip drawback valves, shown in FIG. 1, taken substantially along the line 2--2 of FIG. 1 and illustrating the nozzle in closed (shut off) position above a container;

FIG. 3 is a vertical view partially in section of the anti-drip drawback sleeve slide valve constructed in accordance with the present invention and showing the valve in open position;

FIG. 4 is a sectional view taken substantially along the line 4--4 of FIG. 3 illustrating the chamber formed between the sleeve and the spindle of the anti-drip drawback valve;

FIG. 5 is a partial sectional view taken substantially along the line 5--5 of FIG. 3 illustrating the upstream and downstream openings or parts of the spindle and illustrating the sleeve in half section; and

FIG. 6 is a sectional view taken substantially along the line 6--6 of FIG. 2 illustrating part of the mechanism for moving the sleeve of the anti-drip valve.

PREFERRED EMBODIMENT OF THE INVENTION

Referring now in detail to the drawings, the reference numeral 10 denotes a multiple line filler. Except for the special anti-drip device which is the subject of the instant invention, the multiple line filler may be of any conventional construction. Typical fillers of this type are illustrated, for example, in U. S. Pat. No. 1,700,494 for a Filling Machine issued Jan. 29, 1929, and U. S. Pat. No. 1,992,464 for Straight Line Multiple Filling Machine, issued Feb. 26, 1935. Another typical machine of the same nature and which is essentially similar to the multiple line filler 10 depicted in the accompanying drawings, is shown, described and claimed in U. S. Pat. No. 3,100,513, issued Aug. 13, 1963, for Multiple Line Fillers by Joseph M. Cozzoli and Harold F. Scribner. The particular details of the multiple line filler 10 are not a part of the present invention; nevertheless the following simple description of the basic elements of such a filler will assist in understanding the operation of the within unique anti-drip device.

The multiple line filler 10 includes a frame (not shown) from which the various moving parts are supported. One of the moving parts constitutes an endless conveyor such, for instance, as a belt 12 trained about guide and drive pulleys of which only one pulley 14 is shown. Said pulleys lead and move the endless conveyor 12 through a path which includes a horizontal reach that is supported on a horizontal plate 15. The plate 15 constitutes a part of the stationary frame of the machine. Containers, such, for instance, as bottles 16, are located on the conveyor 12 supported by the horizontal reach 15 and are moved without stopping at a constant speed of travel through the illustrated filling station of said machine. The placement of the bottles 16 on the conveyor 12 and their removal therefrom may be performed either automatically or manually. Said bottles 16 are located on the conveyor 12 in uniformly spaced and predetermined positions, and move in the direction indicated by the arrow A. The only containers 16 that have been shown in FIG. 1 are those directly below filling nozzles 22. The remainder of the containers 16 have been omitted for simplicity of illustration.

The containers 16 are adapted to be filled (charged) by a flying filling head 20. The head 20 includes a group of filling nozzles 22; four being shown in FIG. 1 of the drawings. The actual number of the nozzles 22 will depend upon the design of the machine. Suitable means is included to reciprocate the flying filling head 20 in two different directions. One direction is vertical for insertion of the group of filling nozzles 22 into a corresponding group of bottles 16 and subsequent withdrawal from the bottles 16. The other direction of the flying filling head 20 is horizontal to match the speed of movement of the filling head 20 to the speed of movement of the bottles 16 with the conveyor 12 during the discharge cycle of metering pumps 23 and then to return the filling heads 20 to a position above the next succeeding group of bottles 16.

More particularly, the flying filling head 20 includes a platform 24 to which the filling nozzles 22 are secured. The platform 24 is provided with wheels 26 that slidably mount said platform on a horizontal elongated bar 28 for reciprocating movement restricted to a direction parallel to the length of the bar 28. The bar 28 is attached at its opposite ends to vertical posts 30 slidable in vertical journals 32 (only one of which is shown) that are fast to the frame of the machine. The lower end of each post 30 is provided with a follower 34 that rides on a cam 36 fixed on a horizontal cam shaft 38. The cam 36 is eccentric with respect to the shaft 38 and is so configured that for each revolution of the cam shaft posts 30, the bar 28 will be raised once and lowered once. In the uppermost position of the bar 28, the tips of the filling nozzles 22 are higher than the bottles 16 and, in the lowermost position, the tips of the filling nozzles 22 are inside the bottles 16. Since the platform 24 rides on the bar 28, it likewise is raised once and lowered once for each revolution of the cam shaft 38. Each such revolution of the cam shaft 38 constitutes one cycle of operation of the multiple line filler.

The apparatus also includes a cam shaft 40 which is kinematically connected, e.g., by gearing, to the cam shaft 38 so as to turn synchronously therewith. The two shafts 38 and 40 are connected in a one-to-one turns relationship. The shaft 40 has mounted thereon a closed cam track 42 in which there rides a cam follower 44. The cam follower 44 is mounted on one end of a connecting link 46. The other end of the link 46 is pivoted by a pin 48 to an actuating link 50 which is pivoted to the frame. A guide link 52 pivoted to the connecting link 46 and to the frame holds the link 46 in proper position during its operation. The upper end of the actuating link 50 has mounted thereon a roller 54 that rides in a vertically elongated slot 56 formed in a depending arm 58 functionally integral with the platform 24.

By virtue of the foregoing construction, as the two shafts 38 and 40 rotate in synchronism, the platform 24 will be raised and lowered and will be horizontally shifted to and fro. The two cam tracks are so relatively and independently configured and synchronized to movement of the conveyor 12 that the filling head 20 will experience the following movement for each cycle of the machine.

After filling a group of bottles 16, the head 20, while still moving with and at the same speed as the bottles 16, is raised to lift the filling nozzles 22 from the bottles 16. As soon as the nozzles 22 have been withdrawn, the flying filling head 20 is moved in a direction opposite to the arrow A until the filling nozzles 22 reach a fresh group of bottles 16 just behind the group of bottles 16 that last has been filled. Then the filling head 20 is lowered to insert the filling nozzles 22 into the necks of the fresh group of bottles 16. The filling head 20, as this occurs, has its direction of travel reversed and is moved forward with and at the same speed as the bottles 16 while the metering pumps 23 are actuated to force liquid through the filling nozzles 22 primarily into the bottles 16. Since the present invention is concerned with the anti-drip valves or filling nozzles 22, reference is made to the aforesaid patents and application to more fully explain the mechanism for moving the filling head 20 and synchronizing it to the conveyor 12.

Each of the filling nozzles 22 is connected to a separate metering means schematically illustrated as a group at 23 by a different flexible tube 62. The metering means 23 may be of any standard construction as, for example, they may constitute a series of metering pumps which are adjustable so that during the discharge portion of each cycle a predetermined, i.e., measured, amount of liquid will be forced through the flexible tubes 62 to each discharge nozzle 22 and thence into the bottle 16 in which the nozzle 22 then is located. The tubes 62, for example, may constitute a flexible synthetic plastic such, for instance, as a polyvinyl plastic or rubber. The flexibility is desired in order to permit the flying filling head 20 to reciprocate vertically and horizontally as it performs its previously indicated functions. However, because the tubes 62 experience changes in curvature upon the movement of the filling head 20, said tubes 62 tend to constrict and expand creating a pumping action which might cause undesired post-terminal discharge of liquid from the nozzles 22 after the metering means 23 are cut off and during a non-filling portion of the cycle. The post-terminal discharge is prevented as is hereinafter described by the anti-drip valve 22 which is the principal subject of the present invention.

All of the valves or filling nozzles 22 are alike. Accordingly, only one such nozzle 22 is shown and described in detail. Referring now to FIG. 2, each nozzle 22 includes at its upper end a thimble 64 which is tightly fitted in an opening, not shown, in the platform 24 described above. A thin-walled vertical pipe 68 is tightly fitted into the thimble 64 and extends upwardly from the thimble 64 where it is coupled to the associated one of the flexible hoses 62 shown in FIG. 1. The lower end of the thimble 64 is fitted against and in communication with the bore 66 of a vertical discharge tube or spindle 70.

The spindle 70 may be constructed of any suitable material, such as stainless steel, depending on the exigencies of the filling operation and the liquid to be used in conjunction therewith. The spindle 70, which may have a unitary construction or be of a plurality of joined pieces, has a straight, central, or concentric bore 66 therethrough. The upper end of the spindle 70 is connected to the source of liquid supply from which the liquid under a suitable supra-atmospheric pressure enters the spindle 70. Telescopically ensheathed around part of the outside of the spindle 70 is an outer valve sleeve 72. As is hereinafter described in detail, features of this invention relate to the configuration of the spindle 70 and of the sleeve 72 and to the spacing between them for the different positions of the sleeve 72 on the spindle 70.

The filling apparatus includes operating means to cause the valve sleeve 72 to move or slide relative to the spindle 70. Such operating means is actuated in synchronism with the movement of the filling nozzle 22. The timing is such that the valve sleeve 72 will be in raised position as shown in FIG. 3 when the metering pumps 23 in FIG. 1 are operative and when the filling nozzle 22 is located within the bottles 16. The sleeve 72 will be in a lowered position, shown in FIG. 2, when the metering pumps 23 are cut off. The operating means for each valve sleeve 72 comprises a pneumatic actuator 75 that includes a cylinder 74 in which there is slidable a piston, not shown. Air under pressure is selectively admitted to either the upper or lower end of the cylinder 74 through one of a number of tubes 78 to drive the piston in either vertical direction.

The piston is connected to a piston rod 80, the lower end of which carries a fork 82, shown particularly in FIG. 6. The twin arms of the fork 82 ride in an annular horizontal groove 84 formed in the periphery of the sleeve 72. The stroke of the pneumatic actuator 75 is such that in its lower position, the valve sleeve 72 liquid can pass through the spindle 70 to a bottle 16, and in its upper or raised position, the liquid is blocked or cut off. Fixed to the bottom end of the spindle 70 is a coupling 92 which, in a preferred embodiment, is provided with a female thread 88 so as to engage a male thread 86 formed at the lower end of the spindle 70.

Liquid exits from the spindle 70 through a filling spout 90 which is provided with a male thread 93 operable to engage a female thread 94 formed at the lower end of said coupling 92. Both the spindle 70 and the coupling 92 are stationary during the filling operation but are jointly vertically movable respectively toward and away from the container 16 before and after filling.

The spindle 70 is further provided with at least two axially spaced lateral openings 96 and 98 which communicate with the bore 66 in the spindle 70. Between the lateral openings 96 and 98 is a plug or stopper 100 which is secured in the bore 66 to block the flow of fluid therethrough. The first lateral opening 96 is upstream of the plug 100 and the second lateral opening 98 is downstream of the plug 100. As described above, the sleeve or operator 72 is telescopically disposed around the spindle 70 and is slidable axially over at least a portion of the spindle 70. This is accomplished by disposing the spindle 70 in a slide fit through a central bore in the sleeve 72. Two O-rings 95 and 97 form air-tight seals preventing any liquid from the bore 66 to leak out through the top of the sleeve 72. Preferably, both ends of the spindle 70 protrude from the sleeve 72 in all positions of the sleeve 72.

The interior of the sleeve 72 defines, in cooperation with the spindle 70, an annular chamber 102 of an outer diameter larger than the spindle 70. In a preferred embodiment of the invention, the sleeve 72 has a non-uniform internal diameter. The annular chamber 102 may be formed in a unitary or one-piece cast sleeve 72, or may be formed utilizing a plug or stopper 114, shown in FIGS. 2, 3, and 5 adapted to engage the external diameter of the spindle 70. The proper placement of the plug 114 effectively seals one end of the annular chamber 102.

The spindle 70 has a non-uniform external diameter: the diameter below the upstream lateral opening 96 is less than the diameter of that part of the spindle 70 disposed at and above the lateral opening 96. In like fashion, the internal diameter of the sleeve 72 is non-uniform and is increased near the area of communication with the lateral openings 96 and 98. The open position of the valve sleeve 72 is such that the annular chamber 102 is disposed so as to connect the first lateral opening 96 with the second lateral opening 98. The annular chamber 102 is such that its axial length is at least equal to and preferably greater than the distance between the two lateral openings 96 and 98. There is thus formed a conduit for the uninterrupted flow of fluid therethrough. This arrangement causes deflection of the flow back into the bore 66 of the spindle 70 via the second lateral opening 98 and to ultimately discharge the liquid from the filling spout.

When the sleeve 72 is moved down with respect to the spindle 70 from its position shown in FIG. 2 to a position shown in FIG. 3 so as to close the valve 22, the top or opened end of the annular chamber 102 is brought into alignment with that portion of the spindle 70 which lies below the first lateral opening 96. This cuts off or closes the passageway through the chamber 102 to interrupt the flow from the bore 66 to the annular chamber 102 to effectively close the valve 22. The movement of the sleeve 72 from the open position (FIG. 3) to the closed position (FIG. 2) interrupts the flow into the annular chamber 102 by shifting the position of the chamber 102 below the area of communication with the first lateral opening 96. When the chamber 102 is shifted downward to its position shown in FIG. 2, it defines a space having a larger volumetric capacity than the space defined by the annular chamber 102 when same communicates with the first lateral opening 96 in the open position of said valve 22 (FIG. 3). The reason for the difference in volumetric capacity is caused by the fact that when the valve 22 is in the opened position (FIG. 3), a relatively long length of the greater external diameter section of the spindle 70 is exposed to the annular chamber 102, whereas in the closed position (FIG. 2), a relatively long length of the small external diameter section of the spindle 70 is exposed to the annular chamber 102.

As described above, when the sleeve 72 is moved down with respect to the spindle 70 from its position shown in FIG. 3 to its position shown in FIG. 2, the chamber 102 is moved away from the opening 96 causing the sleeve 72 to block the opening 96. With the opening 96 blocked by the sleeve 72, the flow of the liquid through the bore 66 is cut off or interrupted. The sleeve 72 blocks the opening 96 after a very small downward movement of the sleeve 72 during the initial part of movement of the sleeve to its position shown in FIG. 2. As illustrated in FIG. 2, the sleeve 72 moves down a considerable distance beyond that necessary to block the opening 96. The movement of the sleeve 72 through this larger distance accomplishes a number of functions which are supplimentary to the cut-off function of the sleeve 72. One additional function of the sleeve is to move the O-ring 97 to a position below the opening 96 such that the O-rings 95 and 97 effectively seal both the upper and lower directions of possible leakage from the opening 96. A second additional function provided by the sleeve 72 is the anti-drip function provided by the valve or nozzle 22.

As indicated above, the anti-drip feature is accomplished by increasing the volume of the chamber 102 as it moves down from its open position of FIG. 3 to its closed position of FIG. 2. The increase in volume is accomplished because of the reduced diameter of the lower portion of the spindle 72. The chamber 102 which is formed between the sleeve 72 and the spindle 70 has a changing volume as the sleeve 72 changes its position relative to the spindle 70. The plug 114 of the sleeve 72 has a smaller internal diameter than the upper portion of the sleeve 72 and mates with the smaller outer diameter of the lower portion of the spindle 70. With the chamber 102 in its upper or open position, it is formed mainly by the larger diameter portion of the spindle 70 and accordingly has a relatively smaller volume. As the chamber 102 is moved down, an increasingly larger inner surface for the chamber 102 is formed by the smaller diameter portion of the spindle 70. The smaller diameter portion of the spindle 70 provides for a greater volume in the chamber 102.

The upper stream or inlet to the chamber 102 from the opening 96 is blocked, as indicated above, but a passageway remains provided through the downstream opening 98 to the bore 66 of the spindle 70. Some liquid will be present in the bore 66 below the opening 98 as the cut off of the liquid flow is accomplished during the initial downward movement of the sleeve 72. As the volume within the chamber 102 is increased, it creates an effective partial vacuum to pull back any liquid in the bore 66 below the opening 98. The partial vacuum or negative pressure created in the chamber 102, in this manner, functions to retract any excess fluid drops at the filling spout 90.

The sleeve 72 remains in its closed or downward position until the next bottle 16 is to be filled. With the spout 90 inserted in the bottle 16, the sleeve 72 is moved to its position illustrated in FIG. 3 to permit the liquid flow through the bore 66. As the sleeve 72 is moved to the position of FIG. 3, it develops initially a small pumping function as the volume in the chamber 102 decreases before the opening 96 is cleared. The decreasing volume of the chamber 102, as the diameter of more of its inner surface is increased, starts the movement of the liquid in the bore 66. Accordingly, as the opening 96 is cleared, the liquid flow is immediately and fully commenced. In this manner, the head 20 in FIG. 1 raises and lowers the valves or nozzles 22 with respect to the moving bottles 16. In its lowered position, the nozzles 22 are operated so that the respective sleeves 72 are moved to their open or raised position. The sleeves 72 are returned to their closed position before the valves 22 are raised from the bottles 16. Each bottle is accordingly filled with the predetermined metered amount of liquid, and as each filling operation terminates, any drops at the filling spouts 90 are retracted.

It thus will be seen that there is provided apparatus which achieves the objects of this invention and which is well adapted to meet the conditions of practical use. As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein described or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Claims

Having thus described the invention, what I claim as new and desire to be secured by Letters Patent is as follows:

1. A valve comprising a spindle having a bore extending therethrough, a first lateral opening in communication with said bore, a second lateral opening in communication with said bore, blocking means located in said bore for preventing communication between said first lateral opening and said second lateral opening through said bore, said spindle having a constant external diameter section extending from a location between said first and second lateral openings past said second lateral opening and a reduced external diameter section extending from said location between said first and second lateral openings past said first lateral opening, a sleeve disposed over said spindle and movable in an axial direction relative to said spindle and having a first position and a second position relative to said spindle, said sleeve having a portion with an increased internal diameter defining an annular chamber with said spindle, said chamber having an axial length greater than the axial length between said first and second lateral openings, said sleeve preventing communication between said second lateral opening and said chamber in the first position of said sleeve relative to said spindle and establishing communication between said first and second lateral openings through said chamber in the second position of said sleeve relative to said spindle, said first lateral opening communicating with said chamber when said sleeve is in its first position relative to said spindle, said chamber having a first volume when said sleeve is in its second position relative to said spindle, said chamber having a volume greater than the first volume with said sleeve in its first position relative to said spindle with the pressure in said chamber being lower than when said sleeve is in the second position relative to said spindle whereby excess fluid is drawn back from the tip of said spindle into said bore.

2. A valve according to claim 1 wherein said blocking means includes a plug positioned in said bore of said spindle to interrupt the flow of fluid through said bore, said plug being disposed between said lateral openings of said spindle.

3. A valve according to claim 1 further including means for selectively moving said sleeve to the first and second positions relative to said spindle.