United States Patent Purcell, Jr.
[54] RESERVE LIQUID STORAGE AND [4 1 June 13, 1972 3,405,845 10/1968 Cook etal ..222/389X Primary Examiner-Samuel F. Coleman Att0mey-'l'homas A. Lennox, Robert H. Robinson, Raymond L. Balfour and Anthony J. Rossi [57] ABSTRACT A reserve liquid storage and dispensing device is described in which liquid stored in a container is dispensed by the motion of a piston. The piston is a tank containing high pressure gas, the gas supplying the energy required to cause the piston to move.
4 China, 4 Drawlng Figures PATENTEDJUH13 1972 3. 669.320
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INVENTOR.
Thomas H. Purcell, Jr.
1 RESERVE LIQUID STORAGE AND DISPENSING DEVICE BACKGROUND OF THE INVENTION 1 Field of the Invention This device relates to reserve type primary batteries and in particular to remotely operated reserve type primary batteries. In a broader concept, it relates to any device where a remotely operated reserve type liquid dispensing means is used. An example of this would be a dispenser for liquid fuel for a rocket device.
2. Description of the Prior Art Remotely activated liquid dispensers for reserve type primary batteries have taken two principal forms. In one, a gas generator such as an explosive match or squib has been used to force liquid battery electrolyte out of a container. In some instances, the container is a flexible bag located in a containing vessel, and in some cases, it is a cylinder with or without a piston working within. In the second, the energy of a compressed spring is used to release the liquid from the container to the point of use. Both these systems have faults. In the first system, because the gas generator is self-destroying, the user is never sure that the gas generator will perform as described. In the second system, the amount of power that can be stored per unit weight is low and the spring operated devices tend to be large and clumsy.
SUMMARY OF THE INVENTION According to this invention, the liquid to be dispensed is contained in a closed container, the container having a piston located therein. The piston itself is a hollow tank containing the activating gas under pressure. Means are provided for directing gas from the gas storage tank to an area confined by the piston and the liquid storage device, forcing the piston to move and dispensing the stored liquid from an outlet on one end of the tank. A pressure sensing device reading the gas pressure within the gas storage tank provides a means for monitoring the energy available in the gas storage tank at any particular moment.
The particular benefits of this constructionare: a high volumetric efficiency in terms of total liquid delivered divided by the system volume; high weight efficiency or ratio of liquid weight divided by total weight; and provision for monitoring the available actuating energy at any time.
In a modified embodiment of the invention, the device can be used to dispense fractional parts of the contained liquid at several instants of time.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a cross section of a simplified liquid storage and dispensing device in accordance with the invention.
FIG. 2 shows a cross section of a second embodiment of the invention making use of a valve to release compressed gas from the gas storage tank.
FIG. 3 shows a cross section of a third embodiment of the invention having the gas control valve external to the liquid storage reservoir.
FIG. 4 shows a cross section of the same embodiment as FIG. 3 after operation of the device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Item 10, FIG. 1, represents a reserve primary battery. This battery, completely inactive when dry, will provide a desired quantity of electric power when filled with electrolyte 12 contained in liquid storage reservoir 14. Reservoir 14 has a central section 16 of uniform cross section, a first end wall 18 and a second end wall 20. An outlet opening 22 connects the inside of reservoir 14 with the dispensing system 24. In order to prevent liquid from running out of outlet 22 prior to the desired time of use, a pressure operated shut-off device is mounted across outlet 22 or in the dispensing system 24. This shutoff device can be a spring loaded valve, a plug or other such device. In FIG. 1, a pressure frangible diaphragm 26 is shown located in an enlargement of system 24.
A tank 28 is located within the liquid storage reservoir 14 normally at the end of the reservoir away from outlet 22. This tank contains compressed gas at a high pressure. Sealing rings such as 30 are provided to seal the opening between reservoir 14 and tank 28, tank 28 thereby, becoming a piston within reservoir 14. The seals 30 effectively separate the liquid storage reservoir into two sections, a liquid containing section 32 and a void section 34. A shaft 36 passes through the first end wall 18 of the liquid storage reservoir. It is fitted with a sealing gland38 where it passes through wall 18 and it has a sharpened end 40.
, The battery 10 may be activated by giving the end of shaft 36 a sharp blow. This will force the sharp end 40 into tank 28. Gas will then escape under pressure into the void portion 34 of reservoir 14 forcing tank 28 toward the second end wall 20.
When the pressure in section 34 becomes high enough, diaphragm 26 will rupture and electrolyte will be fed rapidly to battery 10.
In a second embodiment, the gas storage tank 42 shown in FIG. 2 is in the fonn of a sphere. In this case, the fit of the gas storage tank is sufliciently close that no sealing material is needed between tank 42 and reservoir 14. Tank 42 is closed by a screw valve 44 having valve stem 46. A rotatable shaft 48 passing through end wall 18 engages stem 46 by means of a slip coupling shown at 50in the disengaged condition for clarity, enabling valve 44 to be opened but not hindering motion of tank 42.
A third embodiment is shown in FIGS. 3 and 4. In FIG. 3, hollow spherical piston 52 containing gas under pressure has a coating of low friction material such as teflon around its mid portion to act as sealant. A coil of tubing shown in cross section at 56 connects the interior of piston 52 to valve 58 located outside of reservoir 14. Return pipe-66 connects the outlet of valve 58 to the void portion 34 of reservoir 14. A pressure measuring device 62, such as a bourdon guage, provides a means of monitoring the gas pressure in tank 52 during storage and prior to use. In the case of FIG. 3, the dispenser is shown feeding a reaction motor 64.
FIG. 4 depicts the device of FIG. 3 after the piston has discharged its contents into motor 64. Pipe 56 is now pulled out approximately to its full length and sphere 54 has nested into the second end wall 20, which in this case is of hemispherical shape to accept sphere 54 thereby eliminating unnecessary retention of electrolyte.
The embodiment of the invention depicted in FIGS. 3 and 4 has the further feature of dispensing the contained liquid in several fractional amounts. The amount of liquid dispensed from the reservoir 14 is dependent upon the movement of the spherical piston 52. The movement of piston 52 is dependent upon the quantity of gas delivered from the gas supply within piston 52. The quantity of gas delivered can be controlled by controlled opening and closing of valve 58. Further control can be provided by the use of stop valve 70, FIG. 3.
The materials of construction for this. device must be chosen to be compatible with the liquids to be stored. The speed of transfer of liquid will be determined by its viscosity, the gas pressure available and the geometry of the system. By proper choice of these variables it is possible to get complete discharge of liquid in a matter of a second or less as would be desirable for reserve battery priming. For fuel handling, the period of discharge might well take several minutes or even more.
Having thus fully described my invention and described its I shut-off valve when open providing access for the gas connecting the interior of the gas storage tank to a first within the gas storage tank to the portion of the liquid opening formed in a first end wall of the liquid storage storage reservoir bounded by the first end wall of the reservoir;
reservoir and an end portion of the gas storage tank; d. an operating valve external to the liquid storage reservoir d. a valve operating means extending through the first end 5 tubularly connected between the first opening in the first wall of the liquid storage reservoir and engaging the openend wall of the liquid storage reservoir and a econd ing means of the shut-off valve; and, opening formed through the first end wall of the liquid e. a liquid outlet formed in the second end wall of the liquid storage reserv and storage reservoir. e. an outlet formed in the second end wall of the cylindrical 2. A reserve liquid storage and dispensing device which liquid Storage reservoir- 3. A device as defined in claim 2 in which the gas storage tank is spherical in shape, and the second end wall of the liquid reservoir is a hemisphere.
4. A device as defined in claim 2 in which a gas pressure sensing device is located on the tubular connection between the first end wall of the liquid reservoir and the operating valve.
comprises:
a. a cylindrical liquid storage reservoir having a first and second end wall;
b. a gas storage tank located within the liquid storage reservoir having an external diameter equal to the internal diameter of the liquid storage reservoir and slideably mounted therein;
c. a flexible tube located within the liquid storage reservoir k i I