US3548848A

US3548848A - Explosive actuated valves

Info

Publication number: US3548848A
Authority: US
Inventors: Gerhardt C Stichling
Original assignee: Cartridge Actuated Devices Inc
Current assignee: STURDOBE Corp A CORP OF DE; Sensus Spectrum LLC
Priority date: 1968-06-03
Filing date: 1968-06-03
Publication date: 1970-12-22
Anticipated expiration: 1987-12-22

Description

United States Patent inventor Appl. No.

Filed v Patented Assignee Gerhardt c. Stichling ltoselnnd, NJ.

June 3, 1968 Dec. 22, 1970 Cartridge Actuated Devices, inc. Fair-field, NJ.

a corporation EXPLOSIVE ACTUATED VALVES 3,111,133 11/1963 Fulton etal 3,122,154 2/1964 Siebel et a1. 3,332,432 7/1967 Marsh Primary Examiner-William F. ODea Assistant Examiner-Richard Gerard Attorney-Noite and Noite ABSTRACT: An explosive actuated valve having a valve housing provided with an inlet and an outlet situated along a common axis and defining a straight flow-through path for a fluid through the housing. The valve housing has an elongated hollow interior extending across this common axis of the inlet and outlet, and slidable within the elongated hollow interior of the housing is a piston means which has a starting position situated between the inlet and the outlet, an end position displaced from the starting position and providing for free unobstructed flow of fluid along the common axis of the inlet and outlet through the housing, and the piston means has a third, return position where the piston means cuts off the flow of fluid from the inlet to the housing, the valve being normally closed, being open when the piston means is in its end position, and being again closed when the piston means is in its return position. The housing carries at one end of its elongated hollow interior an opening explosive means for displacing the piston means from its starting to its end position upon actuation of said opening explosive means, and the housing carries, at its end which is opposed to that end where the opening explosive means is situated, a return explosive means for returning the piston means from its end position to its return position upon actuation of the return explosive means. Thus, the explosive actuated valve provides a closedopen-closed operation.

PATENIEDuEcwam I 3,548,848

SHEET 1 n; 2

q- INVENTOR WWW ATTORNEYS EXPLOSIVE ACTUATED VALVES BACKBROUNDOF THE INVENTION The present invention relates to explosive actuated valves.

At the present time valves of this type are either normally closed or normally open. The normally closed type of conventional explosive actuated valve will open a flow path when it is actuated, while the normally open type will close a flow path when it is actuated. Thus, at the present time in order to achieve a closed-open-closed operation it is necessary to use at least two valves connected in series with the first being a normally closed valve which upon actuation will open the flow path and with the second being a normally open valve which upon actuation will close the flow path so as to terminate the flow of fluid.

Explosive actuated valves have been found to be extremely useful for such purposes as fuel control valves in jet propelled or rocket propelled projectiles, for discharge control valves for fire extinguishers, for controlled fluid release valves in tire lighting systems, and for many other purposes where high fluid pressures are encountered where remote control, minimum size and minimum weight 2 are essential, because valves of this type have a small size, a low power requirement, a fast action, a high-pressure capacity,and light weight.

Thus, the conventional valves of this type have several advantages over solenoid, motor, or hand-operated valves, but at the same time they have several disadvantages and faults which-render them unsuitable for certain applications. Thus, with many known explosive actuated normally closed valves, the member which seals the inlet port from the outlet port is an integral part of the valve housing, and when the valve is actuated this sealing member is fractured so that the valve cannot be used a second time. An additional disadvantage of the known'valves of this general type is that they do not provide a positive support for the sealing member both before and after actuation of the valve. This lack of support makes the sealing member susceptible to damage, deformation and sometimes accidental rupture due to pressure surges in the inlet fuel line. Thus, preactuation damage to the sealing member results in deformation thereof which could prevent actuation of the valve when the squibthereof isfired and/or whichcould allow the fractured member to become prematurely released from its sealing position after actuation, thereby partially blocking the fluid flow path. Thus, where high-pressure surges are encountered in a fluid line and where the utmost reliability is essentiaLfthe known explosive actuated normally closed valves are notcompletely satisfactory.

In addition, although a normally closed or a normally open valve of the above general type os of a small size and lightweight, the necessity of using two of these valves to provide a closed-open-closed function defeats the small size of the components and renders the structure undesirably complex.

Thus, it is a primary object of the invention to provide a single valvev which has a stop -start-stop. capability in a structure such asa liquid rocket engine, for example, so that it becomes unnecessary to use more'than one valve in series for this purpose.

Furthermore, it is. an object of the invention to provide an explosive actuated valve which will assure minimum weight, minimum size and maximum reliability, so that all of the criteria which are so important to missile and rocket design functions are met by the valve structure of the invention.

Thus, it is a morespecific object of the invention to provide an explosive actuated valve which will avoid all of the above drawbacks of conventional structures, while providing a single valve which performs with the utmost reliability the functions of (a) sealing fluid from passage through the valve (b) allowing fluid passage through the valve with no obstruction in the path of, flow upon initial actuation, and (c) complete resealing of the valve and obstruction of the fluid passage therethrough upon secondary actuation of the valve.

In addition, it is an object of the invention to provide an explosiveactuatedvalve which has a closed-open-closed function and which at the same time is reusable, less expensive to a manufacture than conventional valves, and more reliable in operation as well as capable of operating at higher inlet fluid pressures than conventional valves.

Another object of the invention is to provide an explosive actuated valve which for the job which it does is smaller in size, lighter in weight, and concomitantly has an absolute minimum of pressure loss for a given fluid flow rate after initial actuation, with the added capability of completely sealing or stopping the flow upon secondary actuation.

Furthermore, it is an object of thepresent invention to provide a universal explosive actuated valve that is capable of being easily adapted to inlet fluid lines and inlet fluid pressures of various different sizes.

SUMMARY OF THE INVENTION The foregoing and other objects of the invention are achieved by providing an explosive actuated valve which has a valve housing provided with an inlet and an outlet arranged along a common axis extending through the housing, so that the inlet and the outlet provide a straight path of fluid flow through the housing of the valve of the invention. This valve housing of the invention has an elongated hollow interior extending transversely across the common axis of the inlet and outlet, and slidable within this elongated hollow interior of the valve housing of the invention is a piston means which initially hasfa predetermined starting position when the valve is closed. This piston means has, in addition, an end position opening the valve to provide for unobstructed flow of fluid from the inlet across the hollow interior of the housing to the outlet along a straight flow. path coinciding with the common axis of theinlet and outlet. This piston means of the valve of the in vention has a third, return position where it cuts off the flow of fluid from the inlet tothe outlet, thus stopping the flow.

An opening explosive means is carried by the valve housing of the invention at onev end, of its hollow interior for displacing the piston means from its starting to its end position upon actuation of the opening explosive means, so that in this way thevalve is displaced from its closed to its open position, and at its endopposed to that endwhere the opening explosive means is situated, the valve housing has at its hollow interior a return; explosive means which upon actuation returns the piston@ means to its return position cuttingoff the flow of fluid from the inlet to the outlet.

In this way, with the single valve structure of the invention the initial actuation by the opening explosive means will bring about opening of thevalve, while the secondary actuation by way of the return explosive means will return the valve to a; closed position.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated by way of example in theaccompanying drawings which form part of this application and in which:

FIG. 1 is a longitudinal sectional elevation of one possible embodiment of an explosive actuated valve according to the invention, the structure being shown in FIG. 1 in its normal starting position where the valve is closed so that fluid cannotflow therethrough;

FIG. 2 shows the structure of FIG. 1 after the opening explosive means has been actuated so that the piston means been displaced from its starting position of FIG. 1 to its end; position which is shown in FIG. 2;

FIG. 3 shows the structure of FIGS. 1 and 2 after the return, explosive means has been actuated so that the piston has now been displaced from its end position of FIG. 2 into its return. position of FIG. 3; and

FIG. '4 is a longitudinal elevation of the piston means, of the valve of the invention.

DESCRIPTION OF A PREFERREDEMBODIMENT Referring now-to FIG. 1, there is shown therein, a valve a common axis 16 which extends through the hollow interior 18 of the housing 10. It will be noted that this hollow interior 18 is of an elongated configuration and extends transversely across the common axis 16 of the inlet 12 and the outlet 14.

The inlet 12 is formed with inner threads for receiving an inlet fitting 20 adapted to be connected to any source of fluid, and at its inner end, in the interior 18 of the housing 10, the inlet fitting 20 carries an integral frangible sealing member 22. Instead of a threaded connection of the inlet fitting 20 to the housing 10, a bayonet connection or high pressure fitting may be provided. The fluid-tight seal of the inlet fitting 20 in the inlet 12 of the housing 18 is achieved, for example, by way of an O-ring 24. The frangible sealing member 22 is an integral part of the fitting 20 which has the sealing member 22 machined thereon and attached thereto through a shear section 26, so that the assembly of fitting 20 with the frangible member 22 is initially completely homogeneous and provides a very reliable obstruction to the flow of fluid.

Situated within the elongated hollow interior 18 of the housing is a piston means 30 which is formed with a cavity 32 in whose interior the frangible sealing member 22 is situated when the piston means 30 is in the starting position thereof shown in FIG. 1. The situation of the sealing member 22 in the cavity 32 of the piston means 30 provides a positive support for the frangible member 22 so that surges in inlet pressure will not undesirably influence the structure. The support of the sealing member 22 in the cavity 32 of the piston means 30 is enhanced by way of an O-ring 34 which is situated in a groove of and surrounds the sealing member 22 and which has a frictional engagement with the inner cylindrical surface of the cavity 32 of the piston means 30.

To the right of cavity 32, as viewed in FIG. 1, the piston means 30 is formed with a through-bore 36 which is of the same diameter as the interior diameter of the inlet fitting and which is adapted to be coaxially aligned with the fitting 20 when the piston means is displaced to its end position. To the left of its cavity 32, as viewed in FIG. 1, the piston means is formed with a recess 38 of frustoconical configuration having its larger end at the left extremity of the piston means, as viewed in FIG. 1, this recess 38 tapering toward the right, as viewed in FIG. 1, for a purpose described below.

The elongated hollow interior 18 of the housing 10 is of a generally cylindrical configuration, and in order to provide for fluid-tight slidable engagement between the piston means 30 and the housing 10 the piston means is provided at the region of is its ends with circular cylindrical portions carrying O-

rings

40 and 42, respectively. It will be noted that the end of the piston means provided with the ring 42 is smaller than the end thereof provided with the ring 40, and in fact the portion of the hollow interior 18 to the right of the axis 16, as viewed in FIG. 1, is of a smaller diameter than the portion of the hollow interior 18 of the housing 10 to the left of the axis 16.

These different diameters of the elongated hollow interior 18 of the housing enable the larger diameter portion thereof to be joined to the smaller diameter portion by a tapered hollow interior portion extending across the axis 16 and defined in part by a hollow interior surface which almost makes a right angle with the axis 16, as is indicated at the region of the inner surface of the housing 10 which is situated at the outlet 14. The exterior surface of the piston means 30 is provided with matching or mating taper, for a purpose described below, and it will be noted that in the starting position of the piston means which is shown in FIG. 1 the tapered surface of the piston means is slightly spaced from the tapered surface of the housing 10.

Situated at the right end of the elongated hollow interior 18 of the housing 10, as viewed in FIG. 1, is an opening explosive means 50 threaded into a threaded bore at one end of the housing 10 and having a fluid-tight connection therewith, as by way of an O-ring 52. This explosive means 50 is of a known construction and has in its interior an explosive squib 54 as well as a booster charge so that upon ignition of the squib 54 explosive gases at very high pressure will be released to act upon the piston means 30. For the purpose of igniting the squib 54 electrical leads 56 are connected thereto and connected into any suitable known circuit which will close the circuit to the squib 54 so as to ignite the latter at a selected instant.

At its end which is opposed to that where the opening explosive means 50 is situated, the housing 10 carries in communication with its hollow interior 18 a return explosive means 60 also having a threaded fluid-tight connection with the housing and being of a construction, known per se, which includes an explosive squib 62 and a booster charge so that upon ignition through closing of a circuit through the leads 64 explosive gasses at very high pressure will be released to act on the piston means. The fluid-tight connection between the explosive means 60 and the housing 18 is achieved by way of an O- ring 66 situated in a groove of the explosive means 60 and pressing against the inner surface of the housing 10.

In accordance with a further feature of the invention, the explosive means 60 carries in the hollow interior of the housing 18 a tubular friction member 68 of cylindrical configuration having an open right end, as viewed in FIG. 1, where the tubular member 68 is tapered, as indicated in FIG. I. This tubular member 68 is also open at its left end, so that the explosive gases derived by ignition of squib 62 can discharge through the tubular friction member 68. This tubular friction member is in the form of a thin-walled cylinder and is made of a metal which will be deformed when received in the recess 38 of the piston means 30. It will be noted that while the left end of the frustoconical recess 38, as viewed in FIG. 1, is large enough to receive the friction member 68, the right, smaller end of the recess 38 is smaller than the diameter of the friction member 68 so that the latter will become deformed, in a manner described below, during displacement of the piston means from the starting position of FIG. 1 into the end position of FIG. 2.

The fitting 20 can be made of any desired size so as to coact with a fluid source through a conduit of any desired diameter, and the outlet 14 is also capable of being adapted to any size conduit through which the fluid flows after passing through the valve of the invention. I

FIG. 4 illustrates the piston means 30 by itself, and it will be noted that FIG. 4 not only clearly illustrates the grooves which receive the O-

rings

40 and 42, but in addition FIG. 4 shows the configuration of the tapered surface 39 which coacts with the mating tapered surface of the hollow interior 18 of the housing 10.

The above-described structure operates in the following manner:

When the parts are in the starting position shown in FIG. 1, flow of fluid along the axis 16 in a straight path through the housing 10 is prevented primarily by way of the frangible sealing member 22. Thus, the valve of the invention has a normally closed position.

When it is desired to open the valve, then, for example in an automatic, programmed manner, the circuit through the leads 56 is closed thus igniting the squib 54 and the booster charge so that the explosive gases will engage the piston means 30 and drive the latter from the starting position of FIG. 1 into the end position of FIG. 2. During this movement the recess 38 will receive in its interior the tubular friction member 68 compressing and deforming the latter so that it has substantially the configuration indicated in FIG. 2. In this way the shock of impact is absorbed by the friction member, and in addition the piston means is prevented from rebounding and will reliably move into engagement with the inner end surface of the explosive means 60 which surrounds and extends radially beyond the tubular friction member 68 and which acts as a stop to determine the position of the piston means 30 when it is in its end position shown in FIG. 2. In this way an extremely reliable placement of the piston means precisely at its end position shown in FIG. 2 is achieved.

In this latter end position the through-bore 36 of the piston has its axis precisely in coincidence with the axis 16, so that an unobstructed flow of fluid from the inlet 20 through the through-bore 36 and through the outlet 14 is reliably achieved with the structure of the invention.

It will be noted that during the displacement of the piston means 30 from the starting position of FIG. 1 to the end position of FIG. 2, the sealing member 22 is sheared from the inlet 20 at the shear section 26. In addition it will'be seen that the O-ring 34 acts at this time to frictionally retain the member 22 in the cavity 32, so that with the structure of the invention it is not possible for the frangible member 22 to have any undesirable influence on the operation of the valve.

At the instant when return of the piston means 30 is desired, the circuit through the leads 64 is closed, thus igniting the squib 62 and providing for theexplosive gases which drive the piston means 30 from its end position of FIG; 2 into its return position of FIG. 3. The recess 38 thus becomes displaced beyond the deformed friction member 68, and the tapered surface 39 of the piston means 30 is tightly wedged against the mating tapered surface at the hollow interior 18 of the housing at the region of its outlet 14. In this way the valve is sealed from flow of fluid therethrough and the tapers of the housing 10 and piston means 30 provide at the engagement therebetween a sufficient force with a line fit of the housing and piston means which will effect a reliable leak-proof seal.

Although not always necessary, either one or both of the tapered surfaces may be coated with a thin film of any elastic or plastic material which will allow itself to become compressed since it is softer than the base material, thereby flowing to form a leak-proof seal.

Thus, the valve of the invention is placed in this way in the position of FIG. 3 where the piston means 30 has reached its return position cutting off the flow of fluid from the inlet 12 to the outlet 14. It will be noted thatwhen the piston means is in the return position of FIG. 3, it is situated closer to the explosive means 50 than when the piston means is in its starting position of FIG. 1. In this latter position the tapered surfaces do not engage each other so that they do not provide any frictional resistance to displacement of the piston means from its starting position of FIG. 1 to its end position of FIG. 2. g

The valve of the invention can be reused. In order to prepare it for reuse, the valve is disconnected and disassembled in its entirety. All of the O-rings are removed and the sheared sealing member 22 is displaced from the cavity of the piston means 30. Now the entire unit is cleaned thoroughly and hydrotested, if required. The parts are now reassembled with new O-rings replacing those which were removed. Finally, two new cartridges are installed and a new inlet fitting 20 is installed with its frangible member 22 again situated in the cavity 32. The valve is now ready for use again.

Thus, it is apparent that with the structure of the invention it is possible to achieve with a single compact valve structure, of utter reliability in its operation, a closed-open-closed function eliminating the necessity of a multiplicity of valves to achieve a similar function while at the same time retaining such advantages as the capability of reusing the valve.

.I claim:

or thereof for displacing said piston' from said intermediate starting position to said first end position thereof upon actuation of said 0 ening explosive means, and return explosive means carried y said housing, at an end of said hollow interior thereof opposed to that end of said hollow interior where said opening explosive means is situated, for displacing said piston from said first end position past said intermediate starting position to said return end position thereof upon actuation of said return explosive means. I

2. The combination of claim 1 which includes an inlet fitting carried by said housing in said inlet thereof and wherein said flow closing means is a frangible closure member which prevents fluid from flowing through said inlet fitting, and is carried by said inlet fitting, and said piston being adapted to shear said frangible closure member from said inlet fitting upon movement of said piston from said starting to said first end position thereof.

3. The combination of claim 2 and wherein said piston is formed with a cavity in which said frangible member is situated when said piston is in said starting position thereof, and said frangible member remaining in said cavity after it is sheared from said inlet fitting by said piston.

4. The combination of claim I and wherein said piston is formed with a through-bore aligned with said inlet and outlet of said housing when said piston is in said first end position thereof for guiding the fluid from saidinlet to said outlet through the interior of said housing,

5. The combination of claim 1 and wherein said return explosive means carries a friction member directed toward said piston and said piston being formed at its end which is directed toward said return explosive means with a recess aligned with said friction member and adapted to receive the latter in the interior of said recess while providing frictional engagement between said friction member and said piston upon movement of the latter from said starting to said first end position thereof.

6. The combination of claim 5 and wherein said friction member is deformable and has initially a substantially cylindrical configuration, said recess of said piston having a 1. An explosive actuated valve comprising a valve housing I having an inlet and an outlet situated along a common axis and providing a straight flow-through path for a fluid, said housing having an elongated hollow interior extending transversely across said common axis of said inlet and outlet, flow closing means fixed to said housing, a piston slidable in said hollow interior of said housing from an intermediate starting position in engagement with said flow closing means to a first end position wherein said closing means is displaced to provide unobstructed flow of fluid from said inlet along said axis through said housing and out of the latter through said outlet thereof, and said piston also having a return end position cutting off flow of fluid from said inlet to said outlet, opening explosive means carried by said housing at one end' of said hollow interi- 7. The combination of claim 1 and wherein said valve housing has in its interior a portion of a tapered configuration tapering from said return explosive means toward said opening explosive means and extending across said axis, said piston having an exterior portion of mating tapered configuration adapted for wedged engagement with said tapered interior portion of said housing when said piston is in said return end position thereof.

8. The combination of claim 7 andwherein said piston is closer to said opening explosive means when said piston is in said return end position thereof than when said piston is in said starting position thereof, and said piston, when in said starting position thereof, being free from and out of wedging engagement with said tapered portion of said hollow interior of said valve housing.

9. The combination of claim 8 and wherein said elongated hollow interior of said housing has an axis perpendicular to said common axis of said inlet and said outlet, said tapered hollow interior portion of said housing being defined in part by a tapered inner surface which extends across said common axis of said inlet and outlet almost at right angles thereto at the region of said outlet of said housing.