US 2204798 A
Description (OCR text may contain errors)
J1me 1940- v G. E. FERGUSON FIRE EXTINGUISHER Filed May 10, 1939 INVENTOR.
ATTORNEYS aaw Patented June 18, 1940 UNITED STATES FIRE EXTINGUISHER- I George Ennis Ferguson, Spring Valley, N; Y., as-
signor to Pyrene Manufacturing Company,
Newark, N. J., a corporation of Delaware Application May 10, 1939, Serial No. 272,823,
This application is a. continuation in party of applicants earlier and once co-pending application Serial No. 132,483, filed March 23, 1937, and subsequently abandoned, the present application being directed to an invention relating to improvements in combined double-acting liquid pumps and pick-up devices used in fire extinguishers of the type containing, as the fire eX- I tinguishing liquid, carbon tetrachloride which must be forcibly expelled from the liquid chamber regardless of the position in which the extinguisher is held when operated.
The general object of the invention is to increase the reliability and prolong the life of such double-acting pumps and pick-up devices when the fire extinguisher containing them is subjected to long continued and severe vibrations (for example, on a policemans motorcycle). tending to injure and ultimately destroy the valve mechanism upon which the reliability of the fire extinguisher depends.
To the above end, the present invention comprises, in a combined double-acting pump and pick-up device for use in a fire extinguisher of the carbon tetrachloride type, the improved means hereinafter described for controlling the delivery of the fire extinguishing liquid to opposite ends of the double-acting pump.
In the drawing, Fig. l is a. central, longitudinal,
sectional view of a fire extinguisher embodying the present invention, certain parts being broken away and other parts being. shown in elevation; Fig. 2 is a view in elevation of the upper pump head; Fig. 3 is a sectional View taken on line 33 of Fig. 2; Fig. 4 is a sectional view taken. on line 4-4 of Fig. 2;. Fig. 5 is a view in elevation. of the lower pump head; Fig. 6 is a sectional view taken on line 5-6 of Fig. 3; Fig. '7 is a sectional View taken on line l-! of Fig. 3. Like, parts are referred to by similar reference characters.
Referring to the drawing, the numeral II] indicates a double-acting pump, arranged within a liquid receptacle ll, having ahead [2,. provided with a retaining plate 13 to which a pump- 5 operating handle (not shown) is adapted to be locked what the extinguisher is not. in use.
The pump H] comprises a metallic pump tube 54, to opposite ends of which are secured: metallic pump heads l5, I5 formed respectively with. ofiset portions l6, l6 and provided with inlet ports IT, IT, respectively. Within the pump heads l6, l6 are inlet valve chambers I8, l8 containing valve balls 20, 20', with which is adapted to cooperate a longitudinally movable ball-spacing and actuating rod 2| carried within ametallic tube 22 of considerably larger diameter suitably connected with the offset portions l6, l6" of the pump heads and communicating with pump. head passages 24, 24.. These passages 24, 24' communicate with the inlet valve chambers l8, l8 and ,5 also communicate through ports 25, 25' with check-valve chambers 26, 26 which communicate respectively with opposite ends of the pump tube l4. through openings 21, 27' provided in the pump heads. That is, the valve balls 28, 28, are arranged within the check-valve chambers 26, 25, and cooperate with their respective seats to close communication between the pump tube l4 and the passages 24, 24; whereas the valve. balls 20, 20' cooperate with their seats to close the inlet ports; l1, l1.
Within the pump tube I4 is arranged a metallic piston-operating member, herein shown as a piston tube 30, which projects through the fire extinguisher head t2, and carries at its inner end a piston 3!. The piston 3| has, a limited move-. ment on the piston tube 3.0 and. is adapted toso move, when the piston tube is being moved outwardly (that. is, upwardly as shown in Fig, 1) as to close inlet ports 32 and open inlet ports 34 formed in the piston tube. Upon reverse (downward) movement of the piston tube 30, the piston 3 I. moves on the piston tube 3i! and closes the ports 34 and opens the. ports 32;. the piston being limited in its, movement in one direction by a collar 35 carried by the piston tube, and being limited in its movement in an opposite direction by a gland nut 36 which is carried at the end of the piston tube 30. A nozzle tube 38 is arranged centrally of the piston tube 39, and is held stationary by reason of its connection with a nozzle 40 which is secured to thev outlet end of the receptacle H. I
The pump I0 is journalled for rotation within the receptacle I 4, at one end on the piston tube 30, and. at its other end on the nozzle tube '38; and the offset portions l6, Hi of the pump heads l5, 15' are of sufiicient. weight to insure pendulum-like turningv of the pump about the piston tube and the nozzle tube when the. extinguisher receptacle II is rotated while held in other than a vertical or substantially vertical. position. Thus the picking up of the fire-extinguishing liquid from the lowest spotin. the receptacle H is assured. a
When it is desired to operate the extinguisher, the operating handle, not shown, is unlocked from the retaining, plate l3 by imparting .to the handle a part turn as is customary. If the piston tube 30. is, then drawn outwardly (upwardly), such tube at first moves with respect to the piston 3|, thereby closing the ports 32 and opening the ports 34. If the extinguisher is being operated with its nozzle 4U pointing generally downwardly, the fire extinguishing liquid will enter the port pass over the unseated valve ball 20' and into the passage 24, thence around the valve ball 28' and into the lower part of the pump through the port 21'. Upon reverse (downward) movement of the piston tube 30, such tube will move with respect to the piston 3|, thereby closing the ports 34 and opening the ports 32, whereupon liquid previously drawn into the pump tube l4 passes through the ports 32 and into the piston tube 30 from which it enters the inlet end (not shown) of the nozzle tube 38 from which it is ejected by way of the nozzle 40. As the piston tube 30 moves inwardly, the valve ball 28 becomes seated and closes the communication previously afforded, through the port 25', between the receptacle H and the lower part of the pump. While the piston 3| is being moved inwardly (downwardly), liquid is drawn through the port I1 and passes up through the passage 24 and the tube 22, from which it enters the passage 24 and passes around the then-unseated valve ball 28 into the pump through the port 21. On the next outward (upward) stroke of the piston tube 30, liquid enters the lower end of the pump tube M, as previously explained; and the liquid which has been drawn into the pump through the port 21 passes from the pump tube through the ports 34 and into the piston tube from which it passes into the nozzle tube 31 and is expelled.
With the nozzle end of the extinguisher pointed generally upwardly, liquid, on the inward (downward) stroke of the piston tube, enters the head |5 through the port ll thereof and passes through the port 2! into the pump tube M, as previously described, the liquid in front of the piston tube 3| being then expelled from the pump through the ports 32, the piston tube 30 and the nozzle tube 38, as also previously described. On the outward (upward) stroke of the piston tube 3!], liquid enters the head l5 through the port l1 and passes into the tube 22 and on into the pump tube l4 through the port 21, the liquid at the rear of the piston 3| being then forced through the ports 34 into the piston tube 30 from which it is directed into and through the nozzle tube 31, as previously described.
While the extinguisher is held in a horizontal position and operated, liquid may be admitted to the pump tube It on the inward and outward strokes of the piston, through either of the ports H and IT, or both of these ports, depending upon the position of the valve balls 20 and 20'. On the inward (downward) stroke of the piston tube 30, liquid will pass around the valve ball 28 and enter the pump tube I 4 through the port 21. During the outward (upward) stroke of the piston tube 30, liquid passes around the valve ball 28' and enters the pump tube I4 through the port 21'. The liquid thus entering the pump tube 14 at opposite ends thereof is expelled, as previously described.
From the foregoing it will become apparent that the pick-up device, which is adapted to rotate with the pump l0 about the longitudinal axis of the pump tube M, includes the pump heads |5, IS, the valve balls 20, 20', 28, 28, the ball-spacing and actuating rod 2| and the tube 22 within which the ball-spacing and actuating rod is carried.
The object sought to be attained by the present invention is realized by so constructing the valve balls 20, 20', 28, 28' that they have a specific gravity slightly less than the specific gravity of the fire extinguishing liquid and by so constructing the ball-spacing and actuating rod 2| that it has a specific gravity substantially equal to that of the fire-extinguishing liquid. Satisfactory relations between the specific gravity of the valve balls, the fire-extinguishing liquid and the ballspacing and actuating rod have been found to exist, for example, when using valve balls made of Bakelite and having a specific gravity of 1.35 and when using carbon tetrachloride (having a specific gravity of 1.591) as the fire extinguishing liquid and when using a ball-spacing and actuating rod made of a composition of paper and Bakelite and having a specific gravity of 1.588, the respective specific gravities just mentioned having been observed at a temperature of 60 F. Even though the difference between the specific gravity of the fire extinguishing. liquid and the specific gravity of the valve balls 20, 20', 28, 28' is such that the valve balls would normally fioat in the fire extinguishing liquid, the function of the valve balls is not impaired in the present embodiment of the invention, because the valve balls 28, 28 are forcibly moved by the internal pump pressure into sealing engagement with their respective seats and because neither of the valve balls 20, 25] need be in sealing engagement with its seat so long as the quantity of fire extinguishing liquid within the receptacle is sufficient to cover the valve seat of whichever valve ball 20, 2|) that may be uppermost during operation of the extinguisher. It is to be observed that as the fire extinguishing liquid recedes from its uppermost level during operation of the extinguisher, the uppermost valve ball moves into sealing engagement with its companion valve seat well before the fire extinguishing liquid assumes such a level as would otherwise permit air to pass into the tube 22 by Way of the uppermost valve seat. As the uppermost valve ball approaches its seated position incident to recession of the level of the fire extinguishing liquid, the weight of such ball becomes sufficient to overcome the slight buoyant effort exerted by the fire extinguishing liquid on the spacing rod 2| and the relatively greater buoyant effort which is exerted by that liquid on the lowermost of the valve balls, so as to insure unseating of the lowermost valve ball and establishing communication between the liquid receptacle and the tube 22 by way of the lower end thereof well before the uppermost valve ball assumes its seated position.
Ordinarily, under such severe conditions of vibrations as are encountered when an extinguisher of the general type to which the present invention relates is used as an accessory to or as part of the equipment of a policemans motorcycle, pronounced vibration of the valve balls on their cooperative seats and against their surrounding chamber walls has resulted in such deformation of the valve seats as to render the valves incapable of sealing the various ports or passages with which they are associated, and in some cases the pounding has taken place as between the valve balls and their surrounding chamber walls to such an extent as to break through the walls with deleterious results. It has been found that the life of an extinguisher constructed according to the present invention is greatly prolonged in cases where the extinguisher is subjected to severe vibrations, the extended life of the extinguisher being due to the above-mentioned specific-gravity relationship which obviates the detrimental pounding of the valve balls on the valve seats and the valve chamber walls and at the same time obviates any undue pounding of the ball-spacing and actuating rod on whichever of its associated valve balls that may be in contact therewith at any given instant.
It will be understood that various structural changes may be made in the fire extinguisher herein shown and described and that allowable tolerances in the particular specific-gravity relationships herein set forth may be resorted to without departing from the spirit of the invention.
What is claimed is:
In a portable hand operated type fire extinguisher, a closed container for a liquid fire extinguishing medium, a combined pick-up device and double-acting liquid pump in said container, inter-communicating valve means at opposite ends of the container controlling the delivery of liquid to said pump, each said valve means including a valve hall adapted to operate in said liquid and having a specific gravity slightly less than the specific gravity of said liquid, and a spacing rod extending between said balls and adapted to operate in said liquid and having a specific gravity approximately the same as that of said liquid.
GEORGE ENNIS FERGUSON.