US 3133558 A
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Description (OCR text may contain errors)
May 19, 1964 J. FAJANS ETAL REAGENT FEEDING MECHANISM Filed Oct. 29, 1962 FIG 2 INVENTORS JACK FAJANS JOHN E. NANKIVELL BY m 8 AGENT United States Patent 3,133,558 REAGENT FEEDING MECHANISM Jack Fajans, 47-42 244th St., Douglaston 62, N.Y., and John E. Nankivell, 30 Riverside Drive, Florham Park,
' Filed Oct. 29, 1962, Ser. No. 233,705
6 Claims. (11. 137--563) This invention relates to chemical processing apparatus, and more particularly to a feeding mechanism for'supplying a reagent in controlled amounts. at a predetermined rate.
Reagent feeding devices for transferring small amounts of chemicals to a process stream are widely employed. It is a common shortcoming of the known devices that they are costly when capable of controlled uniform delivery, and not capable of delivering predetermined amounts of reagent over an extended period when of simple structure.
The primary object of this invention is the provision of a simple and inexpensive chemical feeding device which feeds a reagent to a process stream at a precisely predetermined overall rate.
A concomitant object is the provision of such a feeding device which is capable of functioning over an extended period of time without requiring the attention of an operator.
Another object is the provision of such a feeding device which is composed of few and rugged elements so as to have a long useful life without repairs.
With these and other objects in view, the feeding device of our invention in one of its aspects mainly c0nsists of only a few operating parts. A container holds the material which it is intended to feed. An intake nozzle is arranged in the container. A conduit connects the intake nozzle to a source of suction. A drive mechanism is connected to the nozzle for lowering the same into the container at a predetermined rate.
The exact nature of this invention as well as other objects and advantages thereof will be readily apparent from consideration of the following detailed description of a preferred embodiment when considered in connection with the accompanying drawing wherein:
FIG. 1 is a side elevational, partly sectional view of a feeding device of the invention and of associated structure; and
FIG. 2 shows a detail of the apparatus of FIG. 1 in section on an enlarged scale.
The drawing illustrates a feeding device of our invention in its application to the chlorination of the water in a swimming pool, and it will be understood that it is not limited to such an application.
Referring initially to FIG. 1, there is seen a swimming pool 1 filled with water 2. A centrifugal pump 3 driven by a non-illustrated electric motor in a conventional manner circulates the swimming pool water by withdrawing it from the pool through an intake conduit 4 and returning it to the pool through a discharge conduit 5.
The water 2 in the pool 1 is kept free of undesired organisms by gradual addition of a strong calcium hypochlorite solution 6 from a container 7 provided with a cover 8. For this purpose, the intake conduit 4 is equipped with a nipple 9 near the suction end of the pump 3. A feed pipe 10 of an internal diameter much smaller than that of the intake conduit 4 is attached to the nipple 9. A check valve 20 is arranged in the feed pipe 10 in such a manner as to permit liquid flow through the pipe 10 toward the nipple 9 only.
The feed pipe 10 passes through the cover 8, and one end of a length of flexible or pliable plastic hose 11 is attached to the free end of the pipe 10. The other end of the hose 11 carries a heavy nozzle 12 of soapstone or other material resistant to the hypochlorite solution.
A synchronous gear motor 13 is mounted on the cover 8. Its output shaft 14 extends axially from the motor 13 a sufiicient distance so that the shaft together with two discs 15 axially spaced thereon constitutes a slowly revolving winch. A plastic string 16 is attached at one end to the nozzle 12, and its other end is wound on the shaft 14 between the discs 15 in such a manner that the free length of the string 16 gradually increases when the motor is energized.
The lower end of the hose 11 and the nozzle 12 are seen in enlarged section in FIG. 2. The bore 17 of the nozzle 12 is substantially smaller than that of the hose 11.
The afore-described apparatus operates as follows:
The pump 3 is operated at a suificient capacity so that the resistance of the intake conduit 4 to the flow of the water drawn from the pool 1 is greater than the hydrostatic head in the pool, and that the pressure in the intake conduit 4 at the nipple 9 is substantially lower than atmospheric pressure. The feed pipe 10 is thereby under suction. Hypochlorite solution 6 is drawn from the container 7 until the liquid level in the container drops below the orifice of the bore 17 in the nozzle 12. Air is then sucked into the circulation system in small amounts because of the constriction in the feed conduit at the bore 17. Because of the reduced flow section of the feed conduit the amount of air drawn into the circulating pump is not sufficient to interfere with the water circulation.
The slow rotation of the motor shaft 14 lengthens the string 16 and lowers the nozzle 12 until the orifice of the bore 17 again drops below the liquid surface, and
o'hlorinating solution is drawn into the circulating water. Addition of small batches of hypochlorite solution to the pool continues at a uniform overall rate until the further descent of the nozzle 12 is stopped by the bottom of the container 7, and the container is practically empty. The feeding device is restored to its operating condition by refilling the container 7, withdrawing the string 16 from the container to raise nozzle 12 to the surface of the liquid and winding the string on the shaft 14. In the event of pump shut-down, the check valve 11 prevents water flow from the pool 1 into the container 7.
Many other variations of the feeding device of the invention will readily suggest themselves to those skilled in the art. While a tension member such as the plastic string 16 transmitting the motion of the motor 13 to the pliable hose 11 provides particularly simple means for lowering the nozzle 12 at a controlled rate, other drive means for actuating downward movement of the nozzle can obviously be resorted to.
The invention is not limited to the specific hypochlorite reagent and the treated water selected for the purpose of the disclosure, nor to a specific type of tank such as a swimming pool.
It should be understood, therefore, that the foregoing disclosure relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.
What we claim is:
1. In an arrangement for feeding a substance to a liquid, in combination:
(a) a tank adapted to hold said liquid;
(11) circulating pump means including intake means and discharge means;
(0) a first circulation conduit interposed between said tank and the intake means of said pump means;
(d) a second circulation conduit interposed between said tank and the discharge means of said pump means;
(e) a container adapted to hold said material;
(f) intake nozzle means in said container;
(g) a feed conduit connecting said nozzle means to one of said circulation conduits; and
(h) drive means connected to said nozzle means for lowering the same in said container at a substantially uniform rate.
2. In an arrangement as set forth in claim 1, check valve means in said feed conduit.
3. In an arrangement as set forth in claim 1, said feed conduit connecting said nozzle means to said first circulation conduit. 7
4. In an arrangement as set forth in claim 3, the effective flow section of said feed conduit and of said nozzle means being substantially smaller than the effective flow section of said first circulation conduit.
5. In an arrangement as set forth in claim 1, said drive means including constant speed motor means, winch means driven by said motor means, and an elongated tension member having one end portion trained over said winch means and another end portion secured to said nozzle means for lowering the latter into said container when said motor means drives said winch means.
6. In an arrangement as set forth in claim 5, at least a portion of said feed conduit being pliable.
Purdie Oct. 27, 1936 Robinson Nov. 3, 1942