US3887108A

US3887108A - Pressure release method

Info

Publication number: US3887108A
Application number: US253510A
Authority: US
Inventors: Marvin L Mcdaniel; Michael Ivashuk
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-05-15
Filing date: 1972-05-15
Publication date: 1975-06-03
Anticipated expiration: 1992-06-03

Abstract

A method for quickly releasing fluid from a container adapted to contain high pressure fluid which includes a frangible diaphragm. The method utilizes a pressure release mechanism which includes a guide removably attached to the outside of the container adjacent the diaphragm for guiding a sharpened member into piercing engagement with an edge portion of the diaphragm under the urging of a spring whence the diaphragm bends about its remaining edge portion to allow egress of fluid from the container. The spring can be held in cocked position by means of a movable tapered pin in which position it applied no force to the sharpened member and this pin may be released manually or by other means to allow rupture of said diaphragm. The spring may also be housed in a separate housing along with a metal slug while the cutter may be mounted within a cap adjacent to the diaphragm with its piercing edge engaging the diaphragm. The spring may then be released to drive the slug into the cutter which, in turn, pierces the diaphragm.

Description

United States Patent 1 1 McDaniel et al.

[ 1 June 3, 1975 1 PRESSURE RELEASE METHOD [22] Filed: May 15, 1972 [21] Appl. No.2 253,510

FOREIGN PATENTS OR APPLICATIONS 898,994 12/1953 Germany 220/89 A Primary E.ruminerMartin P. Schwadron Assistant Examiner-Richard Gerard Attorney, Agent, or FirmCushman, Darby & Cushman [57] ABSTRACT A method for quickly releasing fluid from a container adapted to contain high pressure fluid which includes a frangible diaphragm. The method utilizes a pressure release mechanism which includes a guide removably attached to the outside of the container adjacent the diaphragm for guiding a sharpened member into piercing engagement with an edge portion of the diaphragm under the urging of a spring whence the diaphragm bends about its remaining edge portion to allow egress of fluid from the container. The spring can be held in cocked position by means of a movable tapered pin in which position it applied no force to the sharpened member and this pin may be released manually or by other means to allow rupture of said diaphragm. The spring may also be housed in a separate housing along with a metal slug while the cutter may be mounted within a cap adjacent to the diaphragm with its piercing edge engaging the diaphragm. The spring may then be released to drive the slug into the cutter which, in turn, pierces the diaphragm.

2 Claims, 8 Drawing Figures k 1 IIIIIIIIIIIIIIIIII ll '1 BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method for quickly releasing fluids from containers in which they are held at high pressure.

2. Description of the Prior Art Many devices are known for releasing fluids from containers; but most such devices operate too slowly for many purposes such as, for example, the release of gases into auto safety crash bags.

One type of quick release mechanism which might be appropriate for the above-stated purposes is shown in the patent to Bach, et al., US. Pat. No. 3,4l6,548 issued Dec. 17, I968. In Bach, et al., a weakened cap closes the end of a tube which communicates with a high pressure container. When this cap is jarred by an explosively activated squib, a shearing action is started at the weakened portion ofthe cap. The cap then pivots about the portion opposite the squib under the influence of escaping fluid to open a suitably sized aperture through which fluid can escape. The Bach et a] device, of course, requires a relatively great energy input since it uses an explosive charge and thus it would be desirable to find a device which operates as quickly as the Bach, et aI., device but which requires a lower energy input.

One approach is to use a frangible diaphragm which is pierced in the center by a spring loaded cutter, but such devices have heretofore been restricted to fairly low pressure environments since either the diaphragm material must be of low strength or else a very high activating energy was required to pierce the diaphragm.

SUMMARY OF THE INVENTION It is one object of the applicants invention to provide a method for quickly releasing fluid from containers designed to hold high pressure fluids and having diaphragms which are also capable of containing high pressure fluids which requires a minimum of energy input for piercing the diaphragm.

The above and other objects are accomplished in the applicants device by providing a piercing means which pierces a portion of the edge of the diaphragm under the urging ofa spring or other biasing means but allows the fluid escaping from the container to bend the diaphragm about its unpierced edge portion outward from the container. This action, in turn, severs the diaphragm along this edge portion until the diaphragm is completely removed from the orifice to provide a proper aperture for rapid egress of the fluids. By use of this method even a spring may provide the force necessary to pierce a metallic diaphragm which is capable of containing a pressure of thousands of pounds per square inch since only a small aperture need be pierced through the edge of the diaphragm to start the ripping action described above. By way of non-limiting example, a force of 40.5 inch-pounds applied to a piercing means designed in accordance with the invention could pierce a diaphragm capable of withstanding pressures up to l0,000 psi.

Furthermore, the piercing means and biasing means such as a spring lever, low powered powder charge, etc. may be arranged in a guide means for the piercing means which can be removably attached to the high pressure container and so may be used with a plurality of such containers. In addition, since the piercing means is preferably an annular member which conforms to the shape of the diaphragm and thus supplies maximum rigidity and a maximum seating surface for the biasing means with a minimum weight, the fluid may escape through said piercing means and said biasing means to the area of use.

BRIEF DESCRIPTION OF THE DRAWINGS The preferred embodiment of the invention will now be described with reference to the drawings in which:

FIG. 1 is a cross-sectional view along the centerline ofa pressure release device, in accordance with the invention, shown in the cocked position;

FIG. 2 is a cross-sectional view similar to FIG. 1 but in which the piercing means has just pierced the diaphragm;

FIG. 3 is a view along the line A-A in FIG. 2;

FIG. 4 is a cross-sectional view similar to FIG. I but in which the piercing means has pierced the diaphragm and fluid is exiting from the container;

FIG. 5 is a front view of the diaphragm piercer shown in FIGS. 1, 2 and 4;

FIG. 6 is a cross-sectional view along the centerline of a second embodiment of the applicants invention;

FIG. 7 is a cross-sectional view similar to FIG. 6 in which the piercing means has just pierced the dia phragm; and

FIG. Sis a cross-sectional view of the second em bodiment in which the piercing means has pierced the diaphragm and fluid is exiting from the container.

The same elements are designated by the same reference numerals throughout the Figures.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. I, reference numeral 10 designates the wall of a container which is adapted to contain high pressure fluids. A portion of wall 10 is extended in a nipple 12 which is threaded on its exterior at I4. A cap 16 which is threaded on its interior at 18 to mate with threads 14 is screwed thereupon.

To the front part of cap 16 a diaphragm 20 is rigidly fastened by any suitable means. This diaphragm completely seals the aperture 22 through the front part of cap 16 and is fabricated of sufficiently strong material to enclose a pressure of thousands of pounds per square inch. Thus, for example, diaphragm 20 may be fabricated from brass 0.015 inches thick or steel 0.0l2 inches thick.

The front part of cap 16 also includes a plurality of threaded apertures 24 which accept a plurality of threaded fasteners 26. The fasteners 26 removably attach a guide tube 28 which is in axial alignment with aperture 22 to cap 16.

Within and guided by tube 28 are the piercer 30 and the spring 32. Spring 32 may be fastened to or may merely be in contact with piercer 30, in either event, the spring 32, which is stopped at its outer end by annu- Iar stop member 34, exerts a force to right as shown in the Figures upon piercer 30. In FIG. 1, the piercer 30 is restrained from moving to the right under the influence of spring 32 by means of tapered pin 36 which engages a notch 35 in piercer 30. In FIG. 2, the tapered pin 36 has been removed from notch 35 and thus the piercer 30 is urged to the right until the point 31 which is formed by a beveled and angled forward extension of piercer 30 pierces diaphragm 20 along an edge thereof to form a flap.

As can best be seen in FIG. 3, this small initial puncture of diaphragm 20 allows the high pressure fluid within the container to create a moment of force on the flap, acting from the edge area 17 which is left unsupported by the puncture about an axis of rotation defined by the surface of the diaphragm and the two points of

attachment

19A and 198 next to the point 31 which have not been cut. This moment causes the flap of the diaphragm 20 to rip outwardly which allows a greater area of egress for the fluids with the container and pushes the piercer 30 to the left until the position shown in FIG. 4 has been reached. Since both the spring 32 and piercer 30 are hollow, the fluid may exit through these members and the end of guide tube 28 into, for example, an automobile safety crash bag. The annular structure of piercer 30 also ensures the rigidity thereof without requiring a great weight.

The pin 36 may be manually disengaged as shown in the above described embodiment. it may also be activated by a mechanical or electrical instrument such as the decelerometer 38. Thus, the above described pressure release mechanism readily lends itself to fill automobile safety crash bags in response to a sudden deceleration of an automobile.

Whether the tapered pin 36 is removed mechanically or otherwise, only about 5 pounds of force is needed and even this amount can be varied by slightly withdrawing the tapered pin from notch 35. Only this small activating force is required because spring 32 only needs to have a stored energy on the order of about 40.5 inch-pounds to properly urge the point 31 of the piercer 30 into the edge of diaphragm 20.

FIGS. 6 through 8 disclose a second embodiment of the applicants invention. In this embodiment, as in the vessel 10, nipple l2, cap 16 and diaphragm 20 and piercer 30 are identical to those described above, however, the piercer 30, in the second embodiment, is merely seated within cap 16.

A separate tube 28' is provided which is similar to tube 28 and contains a spring 32' similar to spring 32 but. tube 28' is not secured to cap 16 as was tube 28 and tube 28 includes the separate slug 40 of a heavy metallic material which may be locked into position by pin 36'. Thus. when the tube 28' is positioned adjacent cap 16 as shown in FIG. 7 and pin 36' is removed. the slug 40 is urged into piercer 30 which forces the point 31 of piercer 30 into diaphragm 20 to create an aperture therein.

The gases exiting from the aperture in diaphragm 20 then remove the diaphragm in the manner described above and the slug 40 may also be pushed out of the way by the escaping gases as shown in FIG. 8.

While the above description fully covers the preferred embodiments of the applicants invention, many modifications may be made thereto within the scope of the invention. Thus, for example. the shape and thick-- ness of the diaphragm and the piercer may vary as may the pressure of the fluid in the container.

Therefore, the scope of the invention must be ascertained from the following claims.

What is claimed is:

l. A method for quickly releasing fluid under high pressure from a container thereof through an aperture having a diaphragm covering the aperture and sealed around its periphery to the container, said method comprising urging a pointed piercing means through the diaphragm at a location immediately adjacent the periphery of the aperture to form a flap having a free edge portion and an opposite supported portion which is integral with the remainder of the flap; and ripping out the flap from the sealed circumferential edge supported portion of the diaphragm by means of the pressure of the fluid in the container acting against the flap and creating a moment of force which bends the flap about its remaining supported portion.

2. A method as in claim 1 wherein the fluid pressure acting on the diaphragm flap is at least 950 p.s.i.

Claims

1. A method for quickly releasing fluid under high pressure from a container thereof through an aperture having a diaphragm covering the aperture and sealed around its periphery to the container, said method comprising urging a pointed piercing means through the diaphragm at a location immediately adjacent the periphery of the aperture to form a flap having a free edge portion and an opposite supported portion which is integral with the remainder of the flap; and ripping out the flap from the sealed circumferential edge supported portion of the diaphragm by means of the pressure of the fluid in the container acting againsT the flap and creating a moment of force which bends the flap about its remaining supported portion.