Title:
ADJUSTABLE SPRINKLER
United States Patent 3575347
Abstract:
An adjustable pattern water sprinkler having improved adjusting means and an improved nozzle to effect substantially equal water distribution over a selectively variable pattern area.
US Patent References:
Sprinkler with variably controlled pattern
Hurley - September 1957 - 2805098
Rotary lawn sprinkler
Woods - November 1960 - 2962220
Adjustable pattern irrigation sprinkling device
Kennedy - September 1961 - 2999643
Turbine-driven irrigation device
Salminen - June 1963 - 3093313
Rotary pop-up sprinkler employing a fixed cam
Coson - September 1966 - 3272437
Sprinkler with variably controlled pattern
Hurley - September 1957 - 2805098
Rotary lawn sprinkler
Woods - November 1960 - 2962220
Adjustable pattern irrigation sprinkling device
Kennedy - September 1961 - 2999643
Turbine-driven irrigation device
Salminen - June 1963 - 3093313
Rotary pop-up sprinkler employing a fixed cam
Coson - September 1966 - 3272437
Application Number:
04/806072
Publication Date:
04/20/1971
Filing Date:
03/11/1969
View Patent Images:
Export Citation:
Assignee:
The Gates Rubber Company (Denver, CO)
Primary Class:
Other Classes:
239/1, 239/206, 239/DIG.001
International Classes:
B05B3/04; B05B15/10; B05B3/02; B05B15/00; B05B3/00; B05B15/10
Field of Search:
239/97,205,206,232,236,(Pattern Sprinkler/ Digest)/
Primary Examiner:
Wood Jr., Henson M.
Assistant Examiner:
Grant, Edwin D.
Claims:
1. A pattern sprinkler comprising:
2. A selectively variable pattern sprinkler comprising:
3. A selectively variable pattern sprinkler comprising:
4. The device as claimed in claim 3 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
5. A selectively variable pattern sprinkler, comprising:
6. A selectively variable pattern sprinkler comprising:
7. The device as claimed in claim 6 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
8. A popup pattern sprinkler comprising:
9. A selectively variable popup pattern sprinkler comprising:
10. A selectively variable popup pattern sprinkler comprising:
11. The device as claimed in claim 10 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
12. A selectively variably popup pattern sprinkler, comprising:
13. A selectively variably popup pattern sprinkler comprising:
14. The device as claimed in claim 12 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
2. A selectively variable pattern sprinkler comprising:
3. A selectively variable pattern sprinkler comprising:
4. The device as claimed in claim 3 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
5. A selectively variable pattern sprinkler, comprising:
6. A selectively variable pattern sprinkler comprising:
7. The device as claimed in claim 6 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
8. A popup pattern sprinkler comprising:
9. A selectively variable popup pattern sprinkler comprising:
10. A selectively variable popup pattern sprinkler comprising:
11. The device as claimed in claim 10 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
12. A selectively variably popup pattern sprinkler, comprising:
13. A selectively variably popup pattern sprinkler comprising:
14. The device as claimed in claim 12 and further including a deflector mounted to said housing near the fixed area opening of said nozzle in such a manner as to deflect and distribute the jet stream emitted from said nozzle.
Description:
BACKGROUND OF THE INVENTION
This invention relates to water sprinklers, but more particularly, this invention relates to sprinklers having adjustably variable nozzles to effect regulation of water flow rate.
One of the major problems with present day sprinklers of the adjustable pattern type is that of equal water distribution radially away from the sprinkler. Unlike common sprinklers, the adjustable pattern sprinkler is repeatedly used from one location and because of this, the contiguous irrigation area served by an adjustable pattern sprinkler may be repeatedly underirrigated or overirrigated as established by the effective effluent distribution from the nozzle. Typically, contour sprinklers have a nozzle system pivoted around an axis by means of a water motor. The effluent from the sprinkler nozzle may be regulated by throttling water flow to the nozzle or by a channeling water to separate and distinct nozzles, or a combination of both. Throttling a sprinkler nozzle proportionally reduces emitted water flow and disrupts equal water distribution over varying sector areas from the nozzle because the water stream trajectory as emitted from the nozzle is exponentially dependent upon water flow. To attempt equal water distribution for different area sectors of different radii, some of system pivoted the more sophisticated present day sprinklers may vary the rotational speed of the nozzle system in conjunction with throttling nozzle effluent. Nozzle system rotational speed variations may be achieved through bifurcating water flow between the nozzle system and the water motor to effect speed variations from the water motor. Other types of adjustable pattern sprinklers bifurcate water flow through separate and distinct nozzles in an attempt to achieve equal water distribution. Even where multiple nozzles are used, some throttling of the water flow usually takes place before being emitted from the nozzle.
The problems heretofore mentioned have been directed toward equal water distribution. Another problem associated with adjustable pattern sprinklers is that of the adjusting means necessary to achieve a selectively variable sprinkling pattern. Some sprinklers use fixed shape cams which require replacement or special shaping to achieve a desired pattern. One problem with a sprinkler having a fixed cam is at each pattern area requires its own special cam which may be commercially unfeasible. A problem with sprinklers having adjustable cams may be that of adjustment caused by nonlinearity between the adjusting means and the jet stream emitted from the nozzle.
It is the purpose of my invention to overcome the aforementioned problems with a novel nozzle design, and a linear adjusting means.
SUMMARY
One object of my invention is to provide an adjustable pattern sprinkler having improved water distribution characteristics.
Another object of my invention is to provide an adjustable pattern sprinkler where there is substantially no regulated throttling of water flow prior to emittance through the nozzle.
Another object of my invention is to supply an adjustable area sprinkler where water flow to a water motor is substantially constant for all selectively variable patterns.
Still another object of my invention is to provide a single nozzle having water distribution characteristics of a plurality of unthrottled nozzles.
Yet another object of my invention is to provide an improved sprinkler that is easily adjustable to a plurality of selectively variable patterns.
It is another object of my invention to provide an economical adjustable pattern sprinkler of either the portable or popup type.
These and other objects of my invention will become apparent to those skilled in the art upon review of the appended drawings and description thereof.
My invention may be used in conjunction with either portable or popup-type sprinklers. The improved sprinkler has a housing mounted to a base member. The housing contains a typical water motor. A portion of the water flow entering the housing is bled off to drive the water motor. The water bled away for the motor exits the housing through a constant diameter orifice. The water motor rotates the housing at relatively constant speed in fixed relation to the base member. The base member mounts a plurality of eccentrically moveable pins arranged circumjacently. A cam, which engages the pins, is mounted to the housing. As the housing pivots around the base, the cam reciprocates with respect to the housing as induced by alternate engagement of the cam with each successive pin. The amount of cam reciprocation is easily varied by changing the eccentricity of a pin. The cam is directly connected by means of a rod and bellcrank to a gate of a gate-valve. Reciprocating movements of the cam will result in reciprocating movements of the gate. The nozzle comprises an orifice plate and the gate, which has a special shape. The nozzle orifice area is changed by movements of the gate relative to the orifice plate. Accordingly, various jet stream spray patterns from the nozzle are effected by the position of the gate relative to the nozzle plate.
The operation and advantages of my invention may best be understood with reference to the drawings.
FIG. 1 is a sectional view of a side elevation of the device as a popup sprinkler.
FIG. 2 is a disconnected isometric view showing the nozzle, the cam and eccentric pins, and the associated articulated linkage.
FIG. 3 is a view similar to that of FIG. 2 but showing a variation of the nozzle.
FIG. 4 is a view similar to that of FIG. 2 but showing a variation in the nozzle, and cam and follower means.
FIG. 5 is a sectional view of FIG. 4 taken along the line 5-5 showing the attitude of a nozzle orifice.
FIG. 6 is a sectional view of FIG. 4 taken along the line 6-6 showing the attitude of a second nozzle orifice.
FIG. 7 is a side elevation of the device as a portable sprinkler.
TECHNICAL DISCLOSURE
Referring to FIGS. 1 and 2, a preferred embodiment of my invention is depicted as a popup sprinkler 10 contained within a shell 11. A baffle 12 separates the shell 11 into two chambers, a base-receiving chamber 13 and a housing-receiving chamber 14. Major components of the sprinkler include a housing 15 and a base 16. The base-receiving chamber has a fluid entry 17 for connection to a fluid supply source, and a fluid exit 18 that receives the base which has an internal bore 19 defining a fluid inlet 20 and outlet 21. The lower lower of the base 16 is reciprocally mounted to be extensible from the base-receiving chamber. When the base is extended, a collar 22 presses a seal 23 against the baffle 12 to effect a fluidtight base-receiving chamber. The base is captivated from rotating by a tab 24 projecting from the baffle to a slot 25 formed in the base. Although the tab and slot arrangement is preferred, any convenient geometrical shape of base with respect to the fluid exit may be used to prevent rotation of the base in the shell. Gravitational forces are ordinarily sufficient to bias the lower portion of the base into the base-receiving chamber when the sprinkler is not in use. However, a preferred embodiment of this invention utilizes a spring 26 between the baffle 12 and a collar 27 to provide an extra margin of bias force. An optional check valve 28 located in the lower portion of the base-receiving chamber drains said chamber of fluid after the sprinkler has been used.
The upper portion 29 of the base flares radially outward into the housing-receiving chamber 14. A plurality of individually moveable eccentric pins 30 circumjacently arranged, extend through the base. The function of the eccentric pins will be later explained. The housing 15 encases a reduction-geared water motor and said housing mounts a nozzle 35, a cam 36 and an articulated linkage 37 between the nozzle an cam. The housing 15 is pivotally mounted to the base by (1) a nipple 38 formed as an extended portion of the housing 15 and (2) a rod 39 extending through the nipple and the internal bore of the base. The nipple protrudes into the base forming a bearing for rotational stability when the housing is pivoted about the base. A seal 40 minimizes fluid leakage between the housing and base. The reduction-geared water motor is encased within a separate motor chamber 41 formed within the housing. The water motor comprises a water turbine 42 and a gear train. The gear train includes a series of intermeshing reduction worms 43 and gears 44 which finally drive a pinion gear 46 on the outside of the housing. The pinion meshes with a gear 47 formed on the base 16. A small passageway 48 between the housing fluid entry 49 and the motor chamber defines a fluid entry into the water turbine. Water exits the water turbine 42, enters the motor chamber 41, and is emitted through a water motor exit 50. The cam, which has a first 51 and a second 52 motion imparting surface, is reciprocally guided along the lower surface 53 of the housing 15. Either of the motion imparting surfaces may successively engage each of the circumjacent pins 30 as the housing is pivoted about the base. By varying the eccentricity of each successive pin 30, the cam 36 may be selectively reciprocated inwardly A or outwardly B with respect to the housing 15 as said housing is pivoted about the base 16.
One of the novel features of my invention is the adjustable orifice area nozzle 35. The nozzle is mounted at the housing fluid exit 54. It should be noted that in my sprinkler design, the fluid does not travel a tortuous path before being emitted from the nozzle. The main fluid passageway from the base-receiving chamber to the nozzle is relatively free of obstruction. Consequently, little or no throttling occurs as fluid flows from the base to the nozzle. A preferred embodiment of my invention includes a nozzle as depicted by FIGS. 1 and 2. The nozzle comprises a nozzle plate 55 having individually sized orifices 56, an a "stair-stepped" gate 57 which may be urged to partially or completely block each successive orifice. Fluid flow rate from the nozzle is varied by blocking or partially blocking each successive orifice. As shown in FIG. 1, the effective orifice area is reduced when the gate partially blocks an orifice. It is of particular importance to note the orifice area is actually reduced in size; there is no throttling of fluid flow prior to being emitted from any of the fixed area orifices 56. The velocity of the jet stream emitted from the nozzle 35 remains substantially constant through each orifice when one or more other orifices are blocked by the gate. Selective or partial blocking of each individual orifice by the nozzle gate 57 is accomplished by means of the pins 30, the cam 36 and the articulated linkage 37. The articulated linkage comprises a bellcrank 58 extending through the housing 15 at its pivotal axis 59, and a rod 60 connected by a pin 61 to the bellcrank 58. An extended end 61 of the bellcrank meshes into a slot 62 formed in the back of the gate 55. Reciprocatory movements A--B of the cam 36 are translated first to rotational movements C--D of the bellcrank 58 and finally to reciprocatory movements R--S of gate 57 against the nozzle plate 55. The foregoing nozzle characteristics permit the nozzle to be designed for equal water distribution for irrigation sectors of varying radii around the sprinkler.
For the purpose of nozzle design, the area to be irrigated by the sprinkler may be theoretically divided into a plurality of annular rings having equal radial widths. Then, differential area between each successive annular ring is directly proportional to the ratio of the square of the distance of the annular rings away from the sprinkler. The relationship for sizing each successive nozzle orifice is directly proportional to each successive annular area. Accordingly, a nozzle orifice for an annular ring at a 20foot radius would have a size equal to four-ninths that of a nozzle orifice for an annular ring at a 30-foot radius. The cumulative area of the plurality of nozzle orifices may then be chosen for any desired maximum fluid flow rate.
As previously explained, the velocity of the jet stream emitted through any unblocked orifice remains generally unchanged even though one or more of the other orifices are blocked. Thus, an annular ring irrigated by any unblocked orifice receives substantially the same quantity of fluid whether or not another orifice of the nozzle is blocked. In other words, as orifices are blocked, a progressive portion of the total jet stream is deleted but the remaining portion of the jet stream remains unchanged. For the purpose of this disclosure, when a "progressive portion" of the jet stream is deleted or added as by blocking or uncovering an individual orifice, the remaining portion of the jet stream remains generally unchanged in that each unblocked individual orifice supplies essentially a constant quantity of effluent to its assigned annular ring; the term "progressive flow rate" as used herein and in the claims refers to essentially unchanged flow of fluid to each annular ring of an unblocked orifice when one or more orifices are blocked or uncovered. Once the orifices have been sized, the trajectory of the jet stream emitted by the nozzle may be considered. A deflector 33 having a compound surface 34 is preferably used to deflect the jet stream from each successive orifice to its corresponding annular area. The shape of the compound surface may then be calculated using typical trajectory relationships keeping in mind that the jet stream velocity is substantially constant.
When the sprinkler is in use, water under pressure is directed to the base-receiving chamber through the fluid entry 17. Rising water pressure in the base-receiving chamber closes the check valve 28 and reacts against the base cross-sectional area forcing the base and the parts attached thereto in an upwardly manner. The spring 26 is compressed and the seal 23 is pressed against the baffle 12 effecting a substantially fluidtight base-receiving chamber. The housing extends from the shell to a position as indicated by the dotted lines of FIG. 1. The jet stream from the nozzle is now free to clear the upper lip 65 of the shell 11. Water travels up the internal bore 19 of the base and into the housing. The majority of the fluid proceeds to be emitted from the nozzle 35 as a controlled jet stream. A small portion of the water is bled through passageway 48 to drive the water turbine. The water turbine fluid is emitted from the water motor chamber through the exit 50. Water turbine effluent is preferably directed to irrigate a predetermined circular area immediately surrounding the sprinkler. As the water turbine 42 powers the pinion 46 through the series of intermeshing worms 43, and gears 44, the pinion, meshing with the stationary gear 47, pivots the housing 15 around the base 16 at a substantially constant speed. The cam 36 upon successive engagement with the endless row of eccentric pins 30, effects reciprocation of the gate 57 against the nozzle plate 55. It should be noted at this point that one of the salient features of the nozzle is that the gate 57 is hydraulically balanced with respect to the nozzle plate 55. Consequently, no feedback forces are generated to affect the position of the cam; the cam does not have to be in constant engagement with a pin to prevent motion of the gate. Preferably, the shape of the cam surfaces 51 and 52 are such that motion of the gate 57 is directly proportional to the rotational motion of the housing 15 about the base 16. Selectively adjusting the eccentricity of a pin 30 results in selective blockage of a nozzle orifice to effect precise control over the jet stream. The use of a plurality of pins permits selectively variable control over the jet stream at a number of housing azimuth positions. By adjusting the pins 30 to desired positions, the sprinkler will repeatedly irrigate an irregular area. When water flow to the base-receiving chamber 13 is terminated, the housing will return to its original position within the shell as aided by the spring 26 and gravitational forces. Check valve 28 returns to its normally open position and residual water drains from the base-receiving chamber. One reason for draining the sprinkler of residual water is to prevent damage due to freezing in cold climate areas.
ADDITIONAL SPECIES
FIG. 3 depicts a variation in the adjustable orifice area nozzle. Both the nozzle plate 70 and gate 71 have been modified. The plurality of orifices as previously described has been replaced with a wedge-shaped orifice 72 and the stair-stepped gate has been replaced with a ramp gate 71. The shape of the wedge-shaped slot 72 may be established in a manner similar to that described for determining the size of orifices. For example, the wedge-shaped orifice 72 may be thought of as a plurality of orifices arranged closely together. The gate 71 is reciprocated against the nozzle plate 70 by the extended end 61 of the bellcrank in a manner as previously described. Movement of the gate 71 against the nozzle plate 70 effectively adjusts the size of the wedge-shaped orifice 72.
Still another variation in the sprinkler is shown in FIGS. 4, 5 and 6. The eccentric pins have been replaced with a fixed shape cam 75. The cam 75 may be of any desired shape to control the sprinkler irrigation pattern. For example, the cam 75 may have a shape for controlling irrigation of a square, circular, rectangular, et cetera, areas. The cam of the sprinkler of FIGS. 1 and 2 has been replaced with a follower 76. The follower 76 engages the cam 75 as the housing 15 is pivoted. The follower 76 activates the articulated linkage in a manner as previously described. The linkage 37 reciprocates the stair-stepped gate 57 against the nozzle plate 77 to effectively block the successive orifices 78. The sprinkler of FIG. 4 does not require a deflector because of the specially shaped nozzle plate 77. As shown in FIGS. 5 and 6, the nozzle plate 77 has an externally curved surface 79. The orifices 78 have varying attitudes to effect various trajectories of the emitted jet stream. For example, the orifice attitude 80 is greatest for the larger orifice since the orifice emits a jet stream having the longest trajectory. The orifice attitude 81 is the least for the smaller orifice since the orifice emits a jet stream having the shortest trajectory. The orifices between those depicted by FIGS. 5 and 6 have successively decreasing attitudes.
Referring to FIG. 7, a portable sprinkler 85 is depicted incorporating my invention. A stand 86 is attached to the base 87 for portability. Fluid enters the base through the fluid entry 88 and proceeds to a cavity 89. The upper portion of the base 87 mounts an endless row of circumjacent pins 30, as described for the sprinkler of FIGS. 1 and 2. The housing 15 is pivotally mounted to the base at the fluid exit 90 by means of the nipple 91 which is an extension of the housing 15. The housing 15 is pivoted about the base 87 in the same manner as previously described for the popup sprinkler 10. Operational and other physical details for the sprinkler 85 are the same as previously described.
This invention relates to water sprinklers, but more particularly, this invention relates to sprinklers having adjustably variable nozzles to effect regulation of water flow rate.
One of the major problems with present day sprinklers of the adjustable pattern type is that of equal water distribution radially away from the sprinkler. Unlike common sprinklers, the adjustable pattern sprinkler is repeatedly used from one location and because of this, the contiguous irrigation area served by an adjustable pattern sprinkler may be repeatedly underirrigated or overirrigated as established by the effective effluent distribution from the nozzle. Typically, contour sprinklers have a nozzle system pivoted around an axis by means of a water motor. The effluent from the sprinkler nozzle may be regulated by throttling water flow to the nozzle or by a channeling water to separate and distinct nozzles, or a combination of both. Throttling a sprinkler nozzle proportionally reduces emitted water flow and disrupts equal water distribution over varying sector areas from the nozzle because the water stream trajectory as emitted from the nozzle is exponentially dependent upon water flow. To attempt equal water distribution for different area sectors of different radii, some of system pivoted the more sophisticated present day sprinklers may vary the rotational speed of the nozzle system in conjunction with throttling nozzle effluent. Nozzle system rotational speed variations may be achieved through bifurcating water flow between the nozzle system and the water motor to effect speed variations from the water motor. Other types of adjustable pattern sprinklers bifurcate water flow through separate and distinct nozzles in an attempt to achieve equal water distribution. Even where multiple nozzles are used, some throttling of the water flow usually takes place before being emitted from the nozzle.
The problems heretofore mentioned have been directed toward equal water distribution. Another problem associated with adjustable pattern sprinklers is that of the adjusting means necessary to achieve a selectively variable sprinkling pattern. Some sprinklers use fixed shape cams which require replacement or special shaping to achieve a desired pattern. One problem with a sprinkler having a fixed cam is at each pattern area requires its own special cam which may be commercially unfeasible. A problem with sprinklers having adjustable cams may be that of adjustment caused by nonlinearity between the adjusting means and the jet stream emitted from the nozzle.
It is the purpose of my invention to overcome the aforementioned problems with a novel nozzle design, and a linear adjusting means.
SUMMARY
One object of my invention is to provide an adjustable pattern sprinkler having improved water distribution characteristics.
Another object of my invention is to provide an adjustable pattern sprinkler where there is substantially no regulated throttling of water flow prior to emittance through the nozzle.
Another object of my invention is to supply an adjustable area sprinkler where water flow to a water motor is substantially constant for all selectively variable patterns.
Still another object of my invention is to provide a single nozzle having water distribution characteristics of a plurality of unthrottled nozzles.
Yet another object of my invention is to provide an improved sprinkler that is easily adjustable to a plurality of selectively variable patterns.
It is another object of my invention to provide an economical adjustable pattern sprinkler of either the portable or popup type.
These and other objects of my invention will become apparent to those skilled in the art upon review of the appended drawings and description thereof.
My invention may be used in conjunction with either portable or popup-type sprinklers. The improved sprinkler has a housing mounted to a base member. The housing contains a typical water motor. A portion of the water flow entering the housing is bled off to drive the water motor. The water bled away for the motor exits the housing through a constant diameter orifice. The water motor rotates the housing at relatively constant speed in fixed relation to the base member. The base member mounts a plurality of eccentrically moveable pins arranged circumjacently. A cam, which engages the pins, is mounted to the housing. As the housing pivots around the base, the cam reciprocates with respect to the housing as induced by alternate engagement of the cam with each successive pin. The amount of cam reciprocation is easily varied by changing the eccentricity of a pin. The cam is directly connected by means of a rod and bellcrank to a gate of a gate-valve. Reciprocating movements of the cam will result in reciprocating movements of the gate. The nozzle comprises an orifice plate and the gate, which has a special shape. The nozzle orifice area is changed by movements of the gate relative to the orifice plate. Accordingly, various jet stream spray patterns from the nozzle are effected by the position of the gate relative to the nozzle plate.
The operation and advantages of my invention may best be understood with reference to the drawings.
FIG. 1 is a sectional view of a side elevation of the device as a popup sprinkler.
FIG. 2 is a disconnected isometric view showing the nozzle, the cam and eccentric pins, and the associated articulated linkage.
FIG. 3 is a view similar to that of FIG. 2 but showing a variation of the nozzle.
FIG. 4 is a view similar to that of FIG. 2 but showing a variation in the nozzle, and cam and follower means.
FIG. 5 is a sectional view of FIG. 4 taken along the line 5-5 showing the attitude of a nozzle orifice.
FIG. 6 is a sectional view of FIG. 4 taken along the line 6-6 showing the attitude of a second nozzle orifice.
FIG. 7 is a side elevation of the device as a portable sprinkler.
TECHNICAL DISCLOSURE
Referring to FIGS. 1 and 2, a preferred embodiment of my invention is depicted as a popup sprinkler 10 contained within a shell 11. A baffle 12 separates the shell 11 into two chambers, a base-receiving chamber 13 and a housing-receiving chamber 14. Major components of the sprinkler include a housing 15 and a base 16. The base-receiving chamber has a fluid entry 17 for connection to a fluid supply source, and a fluid exit 18 that receives the base which has an internal bore 19 defining a fluid inlet 20 and outlet 21. The lower lower of the base 16 is reciprocally mounted to be extensible from the base-receiving chamber. When the base is extended, a collar 22 presses a seal 23 against the baffle 12 to effect a fluidtight base-receiving chamber. The base is captivated from rotating by a tab 24 projecting from the baffle to a slot 25 formed in the base. Although the tab and slot arrangement is preferred, any convenient geometrical shape of base with respect to the fluid exit may be used to prevent rotation of the base in the shell. Gravitational forces are ordinarily sufficient to bias the lower portion of the base into the base-receiving chamber when the sprinkler is not in use. However, a preferred embodiment of this invention utilizes a spring 26 between the baffle 12 and a collar 27 to provide an extra margin of bias force. An optional check valve 28 located in the lower portion of the base-receiving chamber drains said chamber of fluid after the sprinkler has been used.
The upper portion 29 of the base flares radially outward into the housing-receiving chamber 14. A plurality of individually moveable eccentric pins 30 circumjacently arranged, extend through the base. The function of the eccentric pins will be later explained. The housing 15 encases a reduction-geared water motor and said housing mounts a nozzle 35, a cam 36 and an articulated linkage 37 between the nozzle an cam. The housing 15 is pivotally mounted to the base by (1) a nipple 38 formed as an extended portion of the housing 15 and (2) a rod 39 extending through the nipple and the internal bore of the base. The nipple protrudes into the base forming a bearing for rotational stability when the housing is pivoted about the base. A seal 40 minimizes fluid leakage between the housing and base. The reduction-geared water motor is encased within a separate motor chamber 41 formed within the housing. The water motor comprises a water turbine 42 and a gear train. The gear train includes a series of intermeshing reduction worms 43 and gears 44 which finally drive a pinion gear 46 on the outside of the housing. The pinion meshes with a gear 47 formed on the base 16. A small passageway 48 between the housing fluid entry 49 and the motor chamber defines a fluid entry into the water turbine. Water exits the water turbine 42, enters the motor chamber 41, and is emitted through a water motor exit 50. The cam, which has a first 51 and a second 52 motion imparting surface, is reciprocally guided along the lower surface 53 of the housing 15. Either of the motion imparting surfaces may successively engage each of the circumjacent pins 30 as the housing is pivoted about the base. By varying the eccentricity of each successive pin 30, the cam 36 may be selectively reciprocated inwardly A or outwardly B with respect to the housing 15 as said housing is pivoted about the base 16.
One of the novel features of my invention is the adjustable orifice area nozzle 35. The nozzle is mounted at the housing fluid exit 54. It should be noted that in my sprinkler design, the fluid does not travel a tortuous path before being emitted from the nozzle. The main fluid passageway from the base-receiving chamber to the nozzle is relatively free of obstruction. Consequently, little or no throttling occurs as fluid flows from the base to the nozzle. A preferred embodiment of my invention includes a nozzle as depicted by FIGS. 1 and 2. The nozzle comprises a nozzle plate 55 having individually sized orifices 56, an a "stair-stepped" gate 57 which may be urged to partially or completely block each successive orifice. Fluid flow rate from the nozzle is varied by blocking or partially blocking each successive orifice. As shown in FIG. 1, the effective orifice area is reduced when the gate partially blocks an orifice. It is of particular importance to note the orifice area is actually reduced in size; there is no throttling of fluid flow prior to being emitted from any of the fixed area orifices 56. The velocity of the jet stream emitted from the nozzle 35 remains substantially constant through each orifice when one or more other orifices are blocked by the gate. Selective or partial blocking of each individual orifice by the nozzle gate 57 is accomplished by means of the pins 30, the cam 36 and the articulated linkage 37. The articulated linkage comprises a bellcrank 58 extending through the housing 15 at its pivotal axis 59, and a rod 60 connected by a pin 61 to the bellcrank 58. An extended end 61 of the bellcrank meshes into a slot 62 formed in the back of the gate 55. Reciprocatory movements A--B of the cam 36 are translated first to rotational movements C--D of the bellcrank 58 and finally to reciprocatory movements R--S of gate 57 against the nozzle plate 55. The foregoing nozzle characteristics permit the nozzle to be designed for equal water distribution for irrigation sectors of varying radii around the sprinkler.
For the purpose of nozzle design, the area to be irrigated by the sprinkler may be theoretically divided into a plurality of annular rings having equal radial widths. Then, differential area between each successive annular ring is directly proportional to the ratio of the square of the distance of the annular rings away from the sprinkler. The relationship for sizing each successive nozzle orifice is directly proportional to each successive annular area. Accordingly, a nozzle orifice for an annular ring at a 20foot radius would have a size equal to four-ninths that of a nozzle orifice for an annular ring at a 30-foot radius. The cumulative area of the plurality of nozzle orifices may then be chosen for any desired maximum fluid flow rate.
As previously explained, the velocity of the jet stream emitted through any unblocked orifice remains generally unchanged even though one or more of the other orifices are blocked. Thus, an annular ring irrigated by any unblocked orifice receives substantially the same quantity of fluid whether or not another orifice of the nozzle is blocked. In other words, as orifices are blocked, a progressive portion of the total jet stream is deleted but the remaining portion of the jet stream remains unchanged. For the purpose of this disclosure, when a "progressive portion" of the jet stream is deleted or added as by blocking or uncovering an individual orifice, the remaining portion of the jet stream remains generally unchanged in that each unblocked individual orifice supplies essentially a constant quantity of effluent to its assigned annular ring; the term "progressive flow rate" as used herein and in the claims refers to essentially unchanged flow of fluid to each annular ring of an unblocked orifice when one or more orifices are blocked or uncovered. Once the orifices have been sized, the trajectory of the jet stream emitted by the nozzle may be considered. A deflector 33 having a compound surface 34 is preferably used to deflect the jet stream from each successive orifice to its corresponding annular area. The shape of the compound surface may then be calculated using typical trajectory relationships keeping in mind that the jet stream velocity is substantially constant.
When the sprinkler is in use, water under pressure is directed to the base-receiving chamber through the fluid entry 17. Rising water pressure in the base-receiving chamber closes the check valve 28 and reacts against the base cross-sectional area forcing the base and the parts attached thereto in an upwardly manner. The spring 26 is compressed and the seal 23 is pressed against the baffle 12 effecting a substantially fluidtight base-receiving chamber. The housing extends from the shell to a position as indicated by the dotted lines of FIG. 1. The jet stream from the nozzle is now free to clear the upper lip 65 of the shell 11. Water travels up the internal bore 19 of the base and into the housing. The majority of the fluid proceeds to be emitted from the nozzle 35 as a controlled jet stream. A small portion of the water is bled through passageway 48 to drive the water turbine. The water turbine fluid is emitted from the water motor chamber through the exit 50. Water turbine effluent is preferably directed to irrigate a predetermined circular area immediately surrounding the sprinkler. As the water turbine 42 powers the pinion 46 through the series of intermeshing worms 43, and gears 44, the pinion, meshing with the stationary gear 47, pivots the housing 15 around the base 16 at a substantially constant speed. The cam 36 upon successive engagement with the endless row of eccentric pins 30, effects reciprocation of the gate 57 against the nozzle plate 55. It should be noted at this point that one of the salient features of the nozzle is that the gate 57 is hydraulically balanced with respect to the nozzle plate 55. Consequently, no feedback forces are generated to affect the position of the cam; the cam does not have to be in constant engagement with a pin to prevent motion of the gate. Preferably, the shape of the cam surfaces 51 and 52 are such that motion of the gate 57 is directly proportional to the rotational motion of the housing 15 about the base 16. Selectively adjusting the eccentricity of a pin 30 results in selective blockage of a nozzle orifice to effect precise control over the jet stream. The use of a plurality of pins permits selectively variable control over the jet stream at a number of housing azimuth positions. By adjusting the pins 30 to desired positions, the sprinkler will repeatedly irrigate an irregular area. When water flow to the base-receiving chamber 13 is terminated, the housing will return to its original position within the shell as aided by the spring 26 and gravitational forces. Check valve 28 returns to its normally open position and residual water drains from the base-receiving chamber. One reason for draining the sprinkler of residual water is to prevent damage due to freezing in cold climate areas.
ADDITIONAL SPECIES
FIG. 3 depicts a variation in the adjustable orifice area nozzle. Both the nozzle plate 70 and gate 71 have been modified. The plurality of orifices as previously described has been replaced with a wedge-shaped orifice 72 and the stair-stepped gate has been replaced with a ramp gate 71. The shape of the wedge-shaped slot 72 may be established in a manner similar to that described for determining the size of orifices. For example, the wedge-shaped orifice 72 may be thought of as a plurality of orifices arranged closely together. The gate 71 is reciprocated against the nozzle plate 70 by the extended end 61 of the bellcrank in a manner as previously described. Movement of the gate 71 against the nozzle plate 70 effectively adjusts the size of the wedge-shaped orifice 72.
Still another variation in the sprinkler is shown in FIGS. 4, 5 and 6. The eccentric pins have been replaced with a fixed shape cam 75. The cam 75 may be of any desired shape to control the sprinkler irrigation pattern. For example, the cam 75 may have a shape for controlling irrigation of a square, circular, rectangular, et cetera, areas. The cam of the sprinkler of FIGS. 1 and 2 has been replaced with a follower 76. The follower 76 engages the cam 75 as the housing 15 is pivoted. The follower 76 activates the articulated linkage in a manner as previously described. The linkage 37 reciprocates the stair-stepped gate 57 against the nozzle plate 77 to effectively block the successive orifices 78. The sprinkler of FIG. 4 does not require a deflector because of the specially shaped nozzle plate 77. As shown in FIGS. 5 and 6, the nozzle plate 77 has an externally curved surface 79. The orifices 78 have varying attitudes to effect various trajectories of the emitted jet stream. For example, the orifice attitude 80 is greatest for the larger orifice since the orifice emits a jet stream having the longest trajectory. The orifice attitude 81 is the least for the smaller orifice since the orifice emits a jet stream having the shortest trajectory. The orifices between those depicted by FIGS. 5 and 6 have successively decreasing attitudes.
Referring to FIG. 7, a portable sprinkler 85 is depicted incorporating my invention. A stand 86 is attached to the base 87 for portability. Fluid enters the base through the fluid entry 88 and proceeds to a cavity 89. The upper portion of the base 87 mounts an endless row of circumjacent pins 30, as described for the sprinkler of FIGS. 1 and 2. The housing 15 is pivotally mounted to the base at the fluid exit 90 by means of the nipple 91 which is an extension of the housing 15. The housing 15 is pivoted about the base 87 in the same manner as previously described for the popup sprinkler 10. Operational and other physical details for the sprinkler 85 are the same as previously described.