US 2577337 A
Description (OCR text may contain errors)
Dec. 4, 1951 K. P. LANCASTER SPRINKLER CONTROL Filed July 24, 194'? KERMIT P. LANCASTER A TTORNEYS Patented Dec. 4, 1951 UNITED STATES PATENT OFFICE SPRINKLER CONTROL Kermit Lancaster, Arcadia, Calif.
Application July 24, 1947, Serial No. 763,366
I 1 This invention relates to sprinkling systems and more particularly to a device for auto matically controlling sprinkling systems responsive' to atmospheric conditions.
Most sprinkling systems used in lawns, or orchards, gardens, etc., must be manually operated and therefore possess the inherent disad vantage of being dependent upon human judg ment and inclination for their operation. To eliminate this element of uncertainty sprinkler systems may be operated by control mechanisms adapted to operate the sprinklers responsive to the passage of time. Although possessed of the advantage of certainty of operation, such time responsive control means suffer the disadvantage of being insensitive to the atmospheric conditions which are, in effect, the criteria for determining when watering in required. Thus if the time interval between operating periods is set so as to insure sufiicient water under all'humidity conditions, such a system will be wasteful of water when the humidity is high. Y 7
It is an object of the presentinvention to provide a simple and economical sprinkler controller operable responsive to the same atmospheric con-- ditions which are in the last analysis determinative of the moisture needs of the'plants to be watered. 1 v
The aforegoing and other objects are accomplished according to theinvention bythe provision of a flow control'valve andiapilot valve; the pilot valve being adapted to open and close the flow control valve responsive to atmospheric conditions. In order to accomplish this feature the pilot valve is actuated bvawater-reservoir preferably in the form of a body of absorbent material which is suspended so as to permit movement thereof and is so balanced that the absorption and and desorp-tionof water therein and therefrom will "induce-such movement. The vertical motion of this body of absorbent material is used to actuate the pilot valve through a connecting plunger. I
In one embodiment of the invention the body of absorbent material-is mounted on one end of a lever which is counter-weighted at its opposite end to provide theaforementioned balance. The plunger is depended from the lever 'arm and is raised and lowered thereby soas to open and close the pilot valve. Any means of providing this balanced suspension of the absorbent body may be employed. Thus the absorbent body may be mounted directly; on the plungerand a proper balance may be obtained,by spring;loading the plunger. In shortthepilotvalve.isaptuatBdiby '4 Claims. (01. 299-25) movement of a suspended body of absorbent which is so balanced that variations in weight thereof due to the absorption and desorption of Water will induce this movement. Any means of suspending and balancing the absorbent body is therefore within the contemplation of the in- .vention.
The invention may be more clearly understood by reference to the following detailed description of a specific embodiment thereof which description is taken in reference to the accompanying drawing in which;
Fig. 1 isa diagram of the apparatus showing the control valve in sectional elevation;
Fig. 2 is a sectional elevation taken on the line 2-2 of Fig. 1; and,
Fig. 3 is a sectional elevation taken on the line 3-3 of Fig. 1.
The device is adapted to be mounted in a pit or box on a lawn within range of one of the sprinklers of the lawn sprinking system. For example, it may be mounted in a box I0 having a perforated cover II more or less flush with the surface of the ground The box It is provided with a drain I2 and moisture entering the box either through the perforated cover or the pilot valve, as hereinafter described, passes off through the drain. The control valve l4 although removed from the box I 0 in the diagrammatic view of Fig. 1 may likewise be mounted therein if desired. However, the control valve 14 communicates with the pilot valve 16 through a pipe or tube I! and may therefore be either remote from or close to the pilot valve. The operation of the device is independent of the distance separating the pilot and control valve.
The control valve Iii has an inlet 28 joinable to a water main and an outlet 2| which is connected to the sprinklers of the sprinkling system. Separating the inlet 26 and the outlet 2! is an orifice plate 22 chamfered as shown to provide a seat 22A for the similarly chamfered plug 23. The plug 23 is mounted on the piston shaft 24 which is connected to the piston 26 riding in the chamber 28 in the upper part of the valve M. It will be seen that the cross-section of the chamber 28 and of the piston 28 riding therein is greater than the cross-section of the inlet 2|. Water flowing into the valve body from the inlet 20 is prevented from flowing into the chamber 28 by the sealing ring 35 mounted on the piston shaft 24. A breather hole 3| is provided in the Wall of the valve I4. A by-pass 32 provided with the valve 33 connects the inlet 23, i. e. the pressure sideof thewater main with the chamber 28 through the T nipple 34 mounted in the top 35 of the chamber 28. The line ll communicates between the nipple 34 and the pilot valve l8 providing fluid flow means between the water main and the pilot valve It.
When the pilot valve is closed and the valve 33 is open water pressure developed in the chamber 28 will exert a force on the piston 26 in excess of that exerted on the bottom of the plug 23 by the water pressure in -;the inlet 2!]. This differential in force exerted on the piston '25 and the plug 23 is due to the greater cross-sectional area of the piston 25 and will cause the piston 26 to move downwardly seating the plug 23 in itheseat' 22A. In this condition the sprinklers will be shut oil.
When the pilot valve is open in "the manner hereinafter described the pressure in the chamber 28 will be relieved through the line H and the water passing through the line I? and the pilot valve 16 will flow out of the 'box is through the drain 12. The valve 33 in line .312 is used 'to' hol'cl the water ilow through the bypass and pilot ya'lve to a maximum when the pilot valve is open.
When the pressure is thus relieved in'thechamber 28 the force of the water against the bottom of the plug 23 will unseat the plug to permit water flow from the main through the outlet '2! to the sprinkler. In this manner the operation of the control valve 14 is determined by the pilot valve 16.
The pilot valve 16 is a conventional plunger type valve having the plunger 38 pivotally mounted at its upper end to the lever All. The lever to is suspended on the fulcrum M which is pivotally mounted to the brackets S42 and 43. The brackets 2 and 53 are mounted to a base plate 44 which also supports the .pilot valve IS.
A screen box 46 containing an absorbent material 50 "is mounted on one end of the lever ll] and a counter-weights? is mountedon the opposite end to balance the screen'box it. Asecond adjustment of the balance between the counterweight 41 and the box 45. The adjustment weight 4! may be threaded on the opposite end of the lever or anywhere throughout the length of the lever if desired. In the preferred form of the invention the lever is mounied to the pivot by means of the riser sea in order to impart an eccentric action thereto. This eccentric action serves to induce a sudden and exaggerated :displacement when :the balance is destroyed. This feature is desirable in order to cause rapid actuation of the pilot valve it rather than a gradual opening or closing.
The screen box 1s filled with a water absorbent material 50; peat moss constituting the preferred absorbent material. Although in Figs. 1 and 3 the box is shown to be made of screen such is not a necessary feature of the invention inasmuch as the absorbent material '55] maybe enclosed within any type of container whichpermits the ingress and egress of moisture. 'Thus a perforatedmetal container would .be equally'sa'tisfactory. Further if the absorbent material possesses sufficient structural strength itinay be mounted directly on the lever eliminating the container A6.
As above described the plunger 38 of "the pilot valve 16 :is depended from the lever d0 so that rotation of the lever about the fulcrum 4| will raise and :lower the plunger 38 opening and closing the pilot valve 15. The pilot valve 1-6 has outlet 53 which may open into the bottom of the box 10, as shown, or may be directly connected to the drain.
Although the plunger 38 is shown to be dependent from the lever 40 intermediate the fulcrum 4| and the box 46, such is not a necessary feature of the invention as the pilot valve will work with equal satisfaction if the plunger 38 is dependent from the lever on the opposite side of the fulcrum '41. If this latter type of assembly is employed it is necessary to use a reverse acting pilot valve to compensate for the opposite stroke of the plunger.
' T'Ihecaction of the device is as follows: When the sprinklers .of the'sprinkling system are on, water drops through the perforated cover H and wets :the absorbent material 50 in the box 46. When .a predetermined quantity of water is absorbed "by the material 50 to destroy the lever balance, the lever will rotate clockwise, with reference to Fig. 1-1, depressin the plunger 38 and closing the pilot valve IE. When this happens pressure builds :up in the chamber 28 forcing' the plug 23 against the seat 22A so aslto shut off the water to thesprinklers. When water in sufiicient quantity has evaporated from the absorbent ma-- terial in the box :46 me counter-weight A l causes the rotation of the lever M in :a counter-clockwisedi-rection, raising the plunger -38 and opening the pilot valve Hi. When the :pilot valve 15 is opened-in this manner the pressure in the cylinder-28 is relieved through the line F! and the pilot valve 16 and the water pressure developed in the inlet 20 raises the plug 23 thereby opening the valve and turning the sprinklers back on.
The water needs of a lawn or other types of vegetation are of course dependent upon the evaporation rate therefrom. By the provision of a sprinkler controlling system which is likewise dependent upon evaporation rate the sprinkling system maybe controlled responsive to the water requirements a of the vegetation. Further the controlling system of the invention is provided with means of adjustment, -i. -e. the balance 4% so that the particular point at which the sprinklers are turned on, with reference 'to the moisture content of the ground, may be *variedin conformity with the moisture requirements of particular types of vegetation.
Many modifications in the controller of the invention may occur to those "skilled in the art without departure from the scope of the invention. Thus although the "control valve M has been shown outside of the box it may, if desired,
be placed within the box I10. Similarly, theapparatus may be mounted on the .surface of the ground as well as counter-sunk therein without changing its operation. .These and other modifications of similar nature are included within the contemplation of the invention as set forth in the :foregoing description and the :following ate the pressure control valve,;means for oper- :the inlet .52 to which line I1 is attached and the andpilot valve to actuate said pilot valve responsi-ve 'to vertical displacement of the body.
12. An apparatus according to claim 1 wherein the structure of water absorbent material comprises peet moss.
3. In a sprinkler system including a pressure control valve and a pilot valve operable to actuate the pressure control valve, means for operating the pilot valve comprising a lever pivotally mounted about the pilot valve, a structure of water absorbent material mounted on one end of the lever and disposed to receive water directly from the sprinklers, a plunger pivotally depending from the lever and adapted to open and close the pilot valve responsive to motionof the lever, and means balancing the lever so that motion thereof will be dependent upon the quantity of water in the material.
4. An apparatus according to claim 3 wherein the lever is so pivoted as to include a sudden and exaggerated displacement when the balance is destroyed.
KERMIT P. LANCASTER. REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS m Number Name Date 453,997 Folger June 9, 1891 476,376 Fleming June 'I, 1892 1,898,248 Gaines Feb. 21, 1933 1,992,877 Monthan Feb. 26, 1935 15 2,004,194 Mulhall June 11, 1935 2,445,717 Richards July 20, 1948