WO2008068583A1

WO2008068583A1 - Long-range pop-up sprinkler

Info

Publication number: WO2008068583A1
Application number: PCT/IB2007/003720
Authority: WO
Inventors: Arno Drechsel
Original assignee: Arno Drechsel
Priority date: 2006-12-01
Filing date: 2007-11-30
Publication date: 2008-06-12
Also published as: WO2008068583A9; ITVI20060346A1; EP2091662A1

Abstract

A pop-up sprinkler device comprises a housing (2) designed for underground installation, a sprinkler (3) designed to be inserted in the housing, fitting means for hydraulic connection of the sprinkler (3) to external pressurized fluid supply means (3) susceptible of moving it from a lower stop end inoperative position within the housing (2) to an upper stop end operative position outside the housing (2). The sprinkler (3) comprises a water gun (4) of the type having an elongate tubular body (5) and a jet -forming end nozzle (8).

Description

LONG-RANGE POP-UP SPRINKLER

Field of the invention

This invention finds application in the art of irrigation devices, and particularly relates to a long-range pop-up sprinkler.

Background of the invention

Pop-up sprinklers are known to be used for irrigating fields, gardens or the like.

Such known pop-up sprinklers generally include a hollow housing designed for underground installation and sprinkler means susceptible to move from a non- operative position within the housing to a raised operative position. The sprinkler means generally include a vertical sprinkling arm having one or more end nozzles, which is adapted to form an "umbrella" jet.

One drawback of these prior art sprinklers is their short operating range, which considerably reduces their applications. For example, in a sport field, the pop-up sprinkler will have to be placed in the middle of the field, wherefore a very long supply line will be needed, involving high breaking risks, high maintenance costs and injury hazards for the personnel.

Furthermore, prior art pop-up sprinklers are not able to evenly irrigate the surfaces to be irrigated, and often create puddles near the spray nozzles, thereby causing soil erosion and poor sprinkling at the areas farthest therefrom.

Furthermore, installation is highly invasive for the field, due to piping extending thereunder, and the large number of sprinklers that are needed to cover a given surface.

Summary of the invention The object of this invention is to overcome the above drawbacks, by providing a pop-up sprinkler that is highly efficient and relatively cost-effective.

A particular object is to provide a pop-up sprinkler having such a long range as to meet the requirements of modern sport facilities.

A further object is to provide a small size pop-up sprinkler.

Another object of the invention is to provide a pop-up sprinkler that can irrigate very large surfaces.

These and other objects as better explained hereafter are fulfilled by a pop-up sprinkler device as defined in claim 1, comprising a housing designed for underground installation, a sprinkler designed to be inserted in said housing, fitting means for connecting said sprinkler to an external pressurized fluid supply line, actuator means associated to said sprinkler to drive it from an inoperative position of lower stop end within said housing to an operative position of upper stop end projecting from said housing and vice versa, wherein said sprinkler comprises an elongate tubular body and an end nozzle which define a jet-generating water gun, said water gun being designed to project out of said housing with said sprinkler in said upper limit stop operative position.

Thanks to this particular configuration, the pop-up sprinkler device of the invention has a much longer range than prior art devices. The water gun acts as a sort of "launching pad" for water that will flow therethrough to the nozzle, which will increase its velocity and hence its range.

The use of a water gun allows irrigation of a very large area, whereas prior art pop-up sprinklers could only irrigate a relatively small area. Consequently, over a given area to be irrigated, a smaller number of sprinklers may be installed, and underground water supply piping can be further simplified, which affords savings in terms of installation and maintenance times and costs. Furthermore, thanks to its long range, the sprinkler device of the invention can be installed relatively far from the surface to be irrigated, which is a critical feature on surfaces designed to be continuously and heavily trampled, such as sport fields or the like. Thus, in a sport field, the sprinkler device of the invention can be installed outside the playing rectangular field, wherefore the integrity of the latter can be preserved, with no excavation or mud-slide occurring therein.

Due to the provision of actuator means in the sprinkler device of the invention, which are designed to drive it from a lower inoperative position within the housing to an upper operative position outside the housing, the device can be protected from any accidental failure and vandalism, and is of no danger to the users of the field in which it is installed.

Advantageous embodiments of the invention are defined in accordance with the independent claims.

For instance, the tubular body may advantageously define a longitudinal axis that is substantially inclined and not perpendicular to the plane defined by the peripheral top edge of said housing with said sprinkler in the upper operative position.

As used herein, the term "axis inclined to a plane" and derivatives thereof shall be intended to indicate an axis that forms an angle other than zero with the relevant plane, i.e. an axis that does not belong to the plane.

Thanks to this configuration, the sprinkler device of the invention will have a very long range.

Advantageously, the actuator means may be of the rotary type, and are designed to pivotally drive the sprinkler about a first axis of rotation between the lower inoperative position and the upper operative position. With this configuration, the sprinkler device of the invention will have a minimized bulk and involve minimized costs for the excavation required for burial of the housing for the water gun.

Conveniently, the sprinkler device of the invention may include pivotal connection means for connecting the fitting means to the water gun so that the latter is able to swing about an axis.

Thanks to the latter characteristics, the sprinkler device of the invention can irrigate a rather large area, and also allows further reduction of the required sprinklers as compared with prior art, considering an equal area to be irrigated.

In a preferred, non exclusive embodiment of the invention, the actuator means can be connected to a first working fluid supply line, the sprinkler can be connected to a second pressurized water line and a circuit may be provided for controlling the inflow of the working fluid to the actuator means and of the pressurized water to the sprinkler.

Advantageously, such circuit may be configured to ensure sequential succession of inflow of the working fluid to the supply means and inflow of water to the sprinkler.

Thus, the sprinkler will only initiate irrigation of the surrounding area after reaching its operative position.

Suitably, the control circuit may be configured to ensure instantaneous inflow of water to the sprinkler.

This will prevent the formation of puddles in the housing and/or around the sprinkler, and the erosion caused thereby.

Also, the control circuit may be configured to allow instantaneous stop of the inflow of pressurized water to the sprinkler as soon as the sprinkler reaches a substantially central swinging position, so that the stop of the inflow of working fluid to the actuator means is substantially simultaneous to the stop of the inflow of pressurized water to the sprinkler.

This will prevent any interference of the sprinkler with the walls of the housing, as it is driven back to the inoperative position.

In a preferred non exclusive embodiment of the invention, the sprinkler device may comprise jet breaker means which are susceptible of periodically interfere with the water gun jet to discontinue its flow and capture part of its energy to rotate and further improve its distribution.

Thus, the sprinkler device of the invention will afford even irrigation of the area to be irrigated, and prevent the formation of water puddles, typically occurring in prior art sprinklers.

Brief description of the drawings

Further features and advantages of the invention will be more apparent from the detailed description of a preferred, non-exclusive embodiment of a sprinkler device according to the invention, which is described as a non-limiting example with the help of the annexed drawings, in which:

FIG. 1 is an axonometric view of the sprinkler device of the invention in the inoperative position, with the working device is indicated by dashed lines;

FIG. 2 is an axonometric view of the sprinkler device of the invention in an intermediate position between the inoperative position and the operative position, in which part of the housing walls are outlined by dashed lines;

FIG. 3 is an axonometric view of the sprinkler device of the invention in the operative position, with part of the housing walls being indicated by dashed lines; FIG. 4 is a side view of the sprinkler device of FIG. 1, with part of the walls of the housing 2 omitted; FlG. 5 is a side view of the sprinkler device of FIG. 3, with part of the walls of the housing 2 omitted;

FIG. 6 is an axonometric view of the sprinkler device of the invention;

FIG. 7 is a further axonometric view of the sprinkler device of the invention; FIG. 8 is a top view of the sprinkler device of the invention;

FIG. 9 is a front view of the sprinkler device of the invention;

FIG. 10 is an axonometric view of the actuator cylinder for driving the sprinkler device of the invention, with the liner omitted;

FIG. 11 is a sectional view of the cylinder of FIG. 8, as taken along a plane Xl-Xl.

FIG. 12 is a schematic view of a first embodiment of the control circuit of the inventive sprinkler device;

FIG. 13 is a schematic view of the circuit of FIG. 12 in an initial step, i.e. with the sprinkler device of the invention in a inoperative position (corresponding to Figure 1) ;

FIG. 14 is a schematic view of the circuit of FIG. 12 in a first operating phase, i.e. with the sprinkler device of the invention in an intermediate position between the inoperative position and the operative position (corresponding to Figure 2); FIG. 15 is a schematic view of the circuit of FIG. 12 in a second operating phase, i.e. with the sprinkler device of the invention in the operating position (corresponding to Figure 3);

FIG. 16 is a schematic view of the circuit of FIG. 12 in a third operating phase, i.e. with the sprinkler device of the invention in an intermediate position between the operative position and the inoperative position.

FIG. 17 is an axonometric view of a second embodiment of the sprinkler device of the invention;

FIG. 18 is a further axonometric view of the second embodiment of the sprinkler device as shown in FIG. 17; FIG. 19 is a schematic view of a second embodiment of the control circuit of the inventive sprinkler device;

FIG. 20 is a schematic view of the circuit of FIG. 19 in an initial phase, i.e. with the sprinkler device of the invention in a inoperative position (corresponding to Figure 1) ;

FIG. 21 is a schematic view of the circuit of FIG. 19 in a first operating phase, i.e. with the sprinkler device of the invention in an intermediate position between the inoperative position and the operative position (corresponding to Figure 2);

FIG. 22 is a schematic view of the circuit of FIG. 19 in a second operating phase, i.e. with the sprinkler device of the invention in the operative position (corresponding to Figure 3); FIG. 23 is a schematic view of the circuit of FIG. 19 in a third operating phase, i.e. with the sprinkler device of the invention in an intermediate position between the operative position and the inoperative position.

Detailed description of a preferred embodiment

Referring to the above figures, the pop-up sprinkler device of the invention, generally designated by numeral 1 , essentially comprises a housing defined by a box-like body 2 and a sprinkler 3 inserted therein, which is able to move from a lower inoperative position within the housing 2, as shown in Figure 1 , to an upper operative position outside it, as shown in Figure 3.

In operation, the box-like body 2 will be buried in a trench dug in the ground.

The sprinkler 3 comprises a water gun 4 of the type having an elongate tubular body 5 with a pressurized water inlet portion 6 and an outlet portion 7 having a jet- forming nozzle 6. When the sprinkler is in the upper operating position, the tubular body 5 defines a longitudinal axis X which is inclined to the plane π defined by the peripheral top edge B, as particularly shown in Figure 3, thereby forming an angle α other than zero.

When underground, the peripheral edge B may be level with the ground. The sprinkler 3 is designed to be connected to a pressurized water supply line L using suitable fitting means, generally designated by numeral 9. Rotary actuator means are further provided, generally designated by numeral 10, for pivotally driving the sprinkler about the axis Z from the lower inoperative position to the upper operative position and vice versa. It shall be understood that the sprinkler can move to the operative position from the inoperative position by a motion other than the rotary motion, such as a translational or rotary and translational motion, without departure from the scope as defined in the annexed claims.

As particularly shown in Figures 1 to 3, the box-like body 2 has a cover 2' pivotally mounted thereto for rotating about a second axis of rotation Z' parallel to the axis Z. By rotating about the axis Z', the cover will move from a closed position, as shown in Figure 1, to an open position, as shown in Figure 3, along with the pivotal motion of the sprinkler 3 from the inoperative position to the operative position. When the sprinkler device 1 is in the inoperative position, the closed cover 2' will make the surface in which the body 2 is buried usable and walkable, while further protecting the sprinkler 3 from vandalism.

For the cover 2' to be automatically opened, the sprinkler 3 has a lever 3' with an elongate end portion 3" rigidly connected thereto and an opposite end 3"' with a wheel W designed to run along a track T.

As the sprinkler 3 pivots from the inoperative position to the operative position, the lever 3' connected thereto will lift the cover 2' with the wheel W running along the track T. Obviously, as the sprinkler 3 pivots from the operative position to the inoperative position, the lever will close the cover 2' in the same manner.

As particularly shown in Figures 6 and 7, the rotational actuator means 10 will include an actuator cylinder 11, whose operation will be described hereinafter, which is mounted to a wall plate 12 attached to opposite walls 13, 13' of the box- like body 2. As particularly shown in Figure 7, the fitting means 9 include a first pipe 14 connected to a rigid elbow 15, which is in turn connected to the water gun 4. Particularly, the elbow 15 has a first end 16 connected to the end portion 17 of the pipe 14 by the rotating joint 18, which is supported by the bracket 19 rigidly attached to the wall plate 12. Also, the elbow 15 has a second end 20 attached to a flange 21 that is coupled to a counterflange 21' in turn connected to the water gun 4. The pipe 14 further has a valve 57 that controls water inflow to the sprinkler 3. This will provide fluid connection between the pipe 14 and the water gun 4.

The elbow 15 is rigidly connected to the head 24 of the shaft 25 of the actuator cylinder 11, to rigidly follow its rotation about the axis Z. In a preferred, non exclusive embodiment, the rigid connection between the elbow 15 and the actuator cylinder 11 may be provided by the lever 3', to minimize the stress on the elbow 15. The lever 3' may have a square receptacle 22 at the end 3", for receiving the square head 24 of the shaft 25. Also, the elbow may have a hollow receptacle 22' for receiving the lever 3'.

Thus, as the shaft 25 rotates, the actuator cylinder will drive into rotation both the lever 3', which will lift the cover 2', and the elbow 15, which will lift the water gun 4, while causing the latter to move from the inoperative position to the operative position and vice versa. Thanks to this configuration, most of the rotational stress will be carried by the lever 3', and the stress on the elbow 15 will be minimized.

As particularly shown in Figures 9 and 10, the actuator cylinder 11 has a liner 11' that defines an inner chamber 26, in which a piston 27 slides along the axis Z while being rotationally locked.

The piston 27 has a bottom wall 28 and a substantially cylindrical side wall with two helically extending grooves 30, 30' defining cam means. As mentioned above, the shaft 25 has the head-defining end portion 24 rigidly connected to the portion 3" of the lever 3', which is in turn rigidly connected to the elbow 15. Also, the shaft 25 has the other end 31 rigidly connected to a crosspiece 32 that acts as a cam follower with both ends 33, 33' equipped with bearings 34, 34' to slide in the helically extending grooves 30, 30'.

The end wall 35 of the actuator cylinder 11 will have a faucet 36 allowing a working fluid to flow into the chamber 26 and exert pressure upon the free surface 37 of the bottom wall 28 of the piston 27, thereby causing its translation along the axis Z in the direction of arrow F-|. Such translation will cause the shaft 25 to rotate about the axis Z, i.e. in the direction of arrow F₂, with the elbow 15 and the water gun 4 attached thereto also rotating with it.

As particularly shown in Figures 6 and 7, a rotating joint 38 is provided between the elbow 15 and the water gun 4, which is designed to swing about the axis Y, as taught by EP-B1 -0544688 by the Applicant hereof.

While the swinging axis Y is shown in the Figures with a substantially vertical orientation, it can have any inclination, as long as it is not parallel to the plane π defined by the peripheral top edge B of the housing 2, without departure from the scope as defined by the annexed claims.

It shall be further understood that the water gun 4 may also be stationary and not designed to swing about the axis Y, without departure from the inventive scope as defined in the annexed claims.

The swing angle β of the water gun 4 will be thus adjustable using special means, still as taught by the above mentioned patent. The rotating joint 38 may be configured as taught by EP-B1-1152835 by the Applicant hereof.

Particularly, a pair of lugs 39, 39' will be provided, which are defined by elongate protrusions of two open rings 40, 40' fitting around a nipple 41 for connecting the joint 38 and the flange 21 , as particularly shown in Figure 9. The nipple 41 may define the substantially vertical axis Y. The water gun 4 will have a bracket 42 rigidly connected thereto, having an elongate protrusion 43 of such a length as to alternately impact the lugs 39, 39' during rotation of the gun 4. The rotation angle β of the water gun 4 can be adjusted by suitable operation of the rings 40, 40'.

The gun has jet-breaker means, generally designated by numeral 44, that can be configured as taught by EP-B1 -0758926 by the Applicant hereof.

In a per se known manner, the jet-breaker means 44 include a rocker 45, coupled to the tubular body 5, which has a deflector 46 that periodically interferes with the jet generated by the nozzle 8 to discontinue its flow. A motion reversal mechanism may be further provided, configured as taught by the above mentioned EP-B1 -0758926.

Thus, the jet will at least partly release its energy to the rocker 45, while inducing forces having both axial and radial components for causing the rocker 45 to transversely swing about the axis X. Furthermore, the rocking motion thereof about the axis X will drive the tubular body 5 into rotation about the axis Y, until the protrusion 43 of the bracket 42 impacts the lug 39, which will stop its rotation in the desired angular position. Now, the motion reversal mechanism will be operated to move the rocker 45 back to its starting position, with the deflector 46 tending to cause an oppositely directed swinging motion thereof and a homologous rotation of the tubular body 5, which will rotate until the protrusion 43 of the bracket 42 impacts the lug 39'.

The sprinkler device of the invention includes a circuit, generally designated by numeral 50, for controlling the inflow of the working fluid to the actuator means 10 and the inflow of the pressurized water to the sprinkler 3. While the actuator means 10 and the sprinkler, as shown in the annexed drawings, are connected to a common source of pressurized water, each of them shall be understood as being able to be individually connected to its own fluid source, and to have a different fluid circulating therein, without departure from the scope as defined by

Il the annexed claims.

The control circuit 50 may generally include sensor means 51 , 51' for detecting the position of the sprinkler 3 both as it rotates about the axis Z and as it rocks about the axis Y, and valve means 51" connected to the sensor means. The valve means 51" may include a first servovalve 53 having an output connected to the input of the actuator means 10 for controlling the rotation of the sprinkler 3 between the inoperative position and the operative position, and a second servovalve 56 having an output connected to a valve 57 for supplying fluid to the sprinkler 3 to control fluid flow into the tubular body 5.

Figures 12 to 16 show a first embodiment of the control circuit 50, which is of the hydraulic type.

As shown by the hydraulic diagram of Figure 12, the circuit 50 has a pressurized water supply line L having a first branch 52 connected to a servovalve 53 that controls water inflow to the actuator cylinder 3 through the faucet 36. A free reflux adjustment valve 54 is further provided on the branch 52.

The circuit 50 also has a second branch 55 incorporating the second servovalve 56 connected to a valve 57 for controlling water inflow to the sprinkler 3. The second servovalve 56 is connected, through the branch 38, to a first hydraulic limit switch 59 associated to the actuator 11, as shown in Figures 4 and 5.

The hydraulic limit switch 59 has an output connected to the input of the second servovalve 56.

Finally, the branch 60 connects the switch 59 to the first servovalve 53.

The first servovalve 53 has an output that can be selectively connected either to the input of the actuator cylinder 11 or to a drain, whereas the second servovalve

56 has an output that can be selectively connected either to the input of the supply valve 57 for controlling water inflow to the sprinkler 3 or to a drain.

The control circuit 50 further comprises a solenoid valve 61 operated by the solenoid 61'. The solenoid valve 61 has an input connected to the pressurized water supply line L and an output that can be selectively connected to the input of the first servovalve 53 or to the input of the first hydraulic limit switch 59.

Furthermore, the solenoid valve 61 is connected through the branch 62 to a second hydraulic limit switch 63 associated to the water gun 4. A timer 64 is also associated to the solenoid.

The second hydraulic limit switch 63 has an input connected to the output of the solenoid valve 61 and an output that can be selectively connected to a drain or sluice.

The control circuit 50 further comprises a timer 64 that can be connected to the solenoid 61' of the solenoid valve 61.

The operation of the circuit 50 is shown in Figures 13 to 16, in which thicker lines indicate water pressure.

Figure 13 shows the circuit 50 in the inoperative position. Here, both the servovalves 53 and 56 and the solenoid valve 61 are under pressure.

Figure 14 shows a first operating step of the circuit 50, which takes place while the cover 2' opens and the water gun 4 pivots from the inoperative position to the operative position. The timer 64 gives a first signal to the solenoid 61 which starts the circuit sequence. Thus, the solenoid 61' opens the solenoid valve 61 , thereby allowing water to flow therethrough. Therefore, water opens the servovalve 53 of the actuator 11 , for water and pressure to flow therethrough. Therefore, the cover 2' opens and the water gun 4 reaches the operative position. It can be noted that the actuator 11 receives water and pressure, while the valve 57 is still under pressure (closed). It can also be noted that the switch 59 is under pressure.

In this first embodiment of the circuit 50, the first sensor means 51 include the switch 59 and a driving screw 65 thereof, associated with the lever 3'. As it rotates about the axis Z, the driving screw 65 of the switch 59 passes from the position as shown in Figure 4 to the position as shown in Figure 5, for switch operation.

Figure 15 shows an operating step of the circuit 50, which takes place while the sprinkler device of the invention is in the operative position. Once the sprinkler has reached its upper limit stop operative position, with the switch 59 being thence operated, water flows into the latter and operates the servovalve 56 for the valve 57, thereby relieving it. Now, water is free to flow and the sprinkler 3 is thereby operated, and starts to rock about the axis Y by an angle β.

Therefore, first the servovalve 53 and then the servovalve 56 will be opened in close sequence, so that the sprinkler 3 will only start fluid delivery when it reaches the upper operative position.

In this first embodiment of the circuit 50, the second sensor means 51' include the switch 63 and a driving cam 66 thereof, rigidly associated with the sprinkler 3. It shall be noted that, during this step, the interaction of the cam 66 with the switch 63 has no consequence.

Figure 16 shows a third and last operating step of the circuit 50, which takes place while the sprinkler 3 moves from the operative position to the inoperative position, i.e. while the cover 2' closes.

A second signal of the timer 64 gives a pulse to the solenoid 61', which drives the solenoid valve 61 back to the start position. The water gun 4 with the solenoid valve 61 in this condition will continue to rock and irrigate the surrounding area until the cam 66 interacts with the switch 63. After such interaction, the valve 57 will instantaneously close, and the supply to the water gun 4 will stop. Thus, the latter will be locked in a substantially central rocking position, corresponding to a position substantially aligned with the median plane π' defined by the body 2, which does not interfere with the closing path of the cover 2'. The hydraulic circuit 50 is brought back to the start position, with the servovalve 56 under pressure and the actuator being relieved, so that the sprinkler 3 can rotate about the axis Z to the inoperative position, with the cover 2' being driven therealong.

This will prevent the tubular body from interfering with the walls 13, 13' of the box 2, as it pivots back from the operative position to the inoperative position.

Figures 17 to 23 show a second embodiment of the invention, in which the inflow of the working fluid to the actuator means 10 and of pressurized water to the sprinkler 3 are controlled by an electrohydraulic circuit 50.

In this embodiment, the sensor means 51 will include a first electric proximity sensor 70 associated with the actuator means 10 to detect the position of the sprinkler 3 as it rotates about the axis Z, whereas the second sensor means 51' will include a second electric proximity sensor 70' associated with the sprinkler 3 to detect the angular position β of the latter as it rocks.

The valve means 51" include a first solenoid valve 71 associated with the actuator means 10 and a second solenoid valve 72 associated with the valve 57 for supplying fluid to the sprinkler 3. Both solenoid valves 71 , 72 have an input connected to the pressurized water supply line L and respective outputs designed for selective connection with the actuator means 10 or with the supply valve 57 or with a drain.

The first and second electric proximity sensors 70, 70' and the first and second solenoid valves 71 , 72 are connected to a central microprocessor unit 77 with a timer 64.

The solenoid valves 71 , 72 are energized by respective solenoids 74, 75 that can be selectively actuated by the microprocessor unit 77.

The microprocessor unit 77 is programmed to process the electric signals from the sensors 70, 70' and sequentially control actuation of the solenoid valves 71 , 72.

Figure 19 shows the electrohydraulic diagram of the second embodiment of the control circuit 50. Figures 19 to 23 represent hydraulic connections on the right and electric connections on the left, for mutual interfacing in a per se known manner. It can be noted that the two valves 71 and 72 are under pressure.

Figure 20 shows a first operating step of this second embodiment of the circuit, which takes place while the sprinkler 3 is in the intermediate position as shown in Figure 2. The timer 64 provides a first signal to the unit 77, which closes the switch 73 and supplies a pulse to the first solenoid 74 while energizing the proximity sensor 70. The solenoid 74 opens in turn the servovalve 71 , thereby allowing water to flow into the actuator cylinder 11 and to pivot the sprinkler 3 about the axis Z to its upper limit operative position.

Figure 21 shows a later step of the operating cycle of the circuit 50. As the proximity sensor 70, previously energized, detects the upper operative position of the sprinkler 3, it closes, thereby energizing the second solenoid 75. Once the latter is energized, it opens the second servovalve 72, thereby allowing the valve 57 to open and the sprinkler 3 to start irrigating, while swinging about the axis Y.

Therefore, first the servovalve 71 and then the servovalve 72 will be opened in close sequence, so that the sprinkler 3 will only start fluid delivery when it reaches the upper operative position.

Figure 22 shows another operating step of the circuit 50. As the timer 64 emits a second signal, the unit 77 will open the switch 73, thereby energizing the second proximity switch 70'. Then, the sprinkler will continue to swing until the lug 76 impacts the proximity sensor 70', which will indicate the right position for closing the valve 72. Thus, the valve 57 will instantaneously close, and the supply to the water gun 4 will stop.

Thus, the latter will be locked in a substantially central rocking position, corresponding to a position substantially aligned with the median plane π defined by the body 2, which does not interfere with the closing path of the cover 2'. The hydraulic circuit 50 is brought back to the start position, with the servovalve 72 under pressure and the actuator 11 being relieved, so that the sprinkler 3 can rotate about the axis Z to the inoperative position, with the cover 2' being driven therealong.

It will be appreciated that a user can change the irrigation time for the sprinkler 3 by simply adjusting the timer 64 in a per se known manner.

It will be also appreciated that the control circuit 50 may be of any type whatever without departure from the inventive scope as defined by the contents of the annexed claims.

The above disclosure shows that the sprinkler device of the invention fulfills the intended objects and particularly meets the requirement of providing a pop-up sprinkler having a long range.

Furthermore, a pop-up sprinkler has been further provided that has a very small size and can irrigate very large surfaces.

The sprinkler device of this invention is susceptible to a number of changes and variants, within the inventive concept disclosed in the appended claims. All the details thereof may be replaced by other technically equivalent parts, and the materials may vary depending on different needs, without departure from the scope of the invention.

While the sprinkler device has been described with particular reference to the accompanying figures, the numerals referred to in the disclosure and claims are only used for the sake of a better intelligibility of the invention and shall not be intended to limit the claimed scope in any manner.

Claims

1. A pop-up sprinkler device comprising: a housing (2) designed for underground installation; - a sprinkler (3) designed for insertion into said housing; fitting means (9) for hydraulic connection of said sprinkler (3) to an external pressurized fluid supply line; actuator means (10) associated with said sprinkler (3) to move it from a stop lower end inoperative position within said housing (2) to a stop upper end operative position projecting from said housing (2) and vice versa; wherein said sprinkler (3) comprises an elongate tubular body (5) and an end nozzle (8) defining a jet-generating water gun (4), said water gun (4) being designed to project out of said housing (2) with said sprinkler (3) in said upper stop end operative position.

2. Device as claimed in claim 1, characterized in that said tubular body 5 defines a longitudinal axis (X) which is substantially inclined to the plane {π} defined by the peripheral top edge (B( of said housing (2), with said sprinkler (3) in the upper operative position.

3. Device as claimed in claim 1 or 2, characterized in that said actuator means (10) are of the rotary type, to cause said sprinkler (3) to rotate about a first axis of rotation (Z) between said stop end inoperative position and said stop end operative position and vice versa.

4. Device as claimed in claim 3, wherein said housing (2) comprises a box-like body that defines a substantially vertical longitudinal median plane (π¹), characterized in that said actuator means (10) comprise an actuator cylinder (11) mounted to the inner side of a wall plate (12) attached to the inner wall of said box- like body (2).

5. Device as claimed in claim 4, characterized in that said actuator cylinder (11) receives a slideably movable, rotationally locked piston (27) therein, said cylinder (11) having a bottom wall (28) and a substantially cylindrical side wall (29) with a helical groove (30, 30') defining first cam means, sad cylinder (11) further comprising a rotating shaft (25) coaxial with said cylinder (11) and having a proximal end (31) accommodated therein.

6. Device as claimed in claim 5, characterized in that said proximal end (31) has a first cam follower element (32) sliding in said first cam means (30, 30') of said cylinder (11) to cause said tubular body (5) to rotate in response to an axial translation of said piston (27).

7. Device as claimed in claim 5, characterized in that said fitting means (9) comprise an elbow pipe (15) having a first end (20) rigidly connected to said sprinkler (3) and a second end (16) in fluid communication with said external supply line and rotatably coupled to a bearing bracket (19) attached to said wall plate (12).

8. Device as claimed in claim 7, characterized in that said elbow pipe (15) is rigidly connected to the distal end (24) of said shaft (25) to cause said sprinkler (3) to rotate about said first axis (Z) and be moved between said lower limit inoperative position and said upper limit operative position.

9. Device as claimed in claim 6, wherein said first cam follower element (32) comprises a bearing (33, 33') mounted to a crosspiece (32) which is integral with said shaft (25) at said first proximal end (31).

10. Device as claimed on one or more of claims 1 to 9, wherein said housing (2) has a cover (2¹) susceptible of moving from a closed position to an open position and vice versa, said sprinkler (3) being connected to said cover (2¹) to open it in said operative position and close it in said inoperative position.

11. Device as claimed in one or more of claims 1 to 10, characterized in that it comprises rotary connection means (38) susceptible of connecting said fitting means (9) to said sprinkler (3) to allow to the latter to swing about a second swing axis (Y) inclined to the first (X) with a maximum predetermined swinging angle (β).

12. Device as claimed in one or more of claims 9 to 11 , comprising a deflector (46) which is susceptible of periodically interfering with the water jet of said sprinkler (3) to capture at least part of its energy and turn it into swinging motion, as well as means for adjusting said swinging angle (β) of said sprinkler (3).

13. Device as claimed in one or more of claims 1 to 12, wherein said sprinkler (3) is connected to a pressurized fluid supply line (L) through a suitable control circuit (50).

14. Device as claimed in claim 13, characterized in that said control circuit (50) includes sensor means (51 , 51') for detecting the position of said sprinkler (3) both as it rotates about said axis of rotation (Z) and as it rocks about said swing axis (Y), and valve means (51") connected to said sensor means for controlling the water flow in said circuit.

15. Device as claimed in claim 14, characterized in that said valve means (51") include a first servovalve (53) having an output connected to the input of said actuator means (10) with a controlled non return valve (54) possibly interposed therebetween, for controlling the rotation of said sprinkler (3) between said inoperative position and said operative position, and a second servovalve (56) having an output connected to a supply valve (57) for supplying fluid to said sprinkler (3) to control fluid flow into said tubular body (5).

16. Device as claimed in claim 15, characterized in that said control circuit (50) further has a first hydraulic limit switch (59) associated to said sprinkler (3) and having an output connected to the input of said second servovalve (56) so that operation of said actuator means (10) and water inflow to said sprinkler (3) take place sequentially as soon as the sprinkler (3) reaches said upper limit operative position.

17. Device as claimed in claim 16, characterized in that said first servovalve (53) has an output that can be selectively connected either to the input of said actuator means (10) or to a drain, said second servovalve (56) having an output that can be selectively connected either to the input of said supply valve (57) for controlling water inflow to said sprinkler (3) or to a drain.

18. Device as claimed in claim 17, characterized in that said control circuit (50) comprises a solenoid valve (61) operated by a solenoid (61'), said solenoid valve

(61) having an input connected to the pressurized water supply line (L) and an output that can be selectively connected to the input of said first servovalve (53) or to the input of said first hydraulic limit switch (59).

19. Device as claimed in any one of claims 16 to 18, characterized in that said control circuit (50) further comprises a second hydraulic limit switch (63) that can be actuated by said sprinkler (3) when said tubular body (5) is in a central position substantially aligned with said median plane (π¹), said second hydraulic limit switch (63) having an input connected to the output of said solenoid valve (61) and an output that can be selectively connected to a drain or sluice, so that, once said second hydraulic limit switch (63) is actuated, it stops water delivery to said sprinkler (3) and consequently stops it in said central position, and then immediately relieves said actuator means (10), whereupon the sprinkler (3) is moved back to said lower limit inoperative position, so that the water gun (49 can be moved back to its initial inoperative position without interfering with the inner walls (13, 13') of said box-like body (2).

20. Device as claimed in any one of claims 14 to 19, characterized in that said control circuit (50) further comprises a timer (64) which is designed to be connected to the solenoid (61') of said solenoid valve (61) to control the motion of said water gun (4) to said upper limit operative position and instantaneous fluid delivery from said sprinkler (3) as soon as its rocking motion is initiated, in response to a first electric signal, and stops said water delivery and moves said sprinkler (3) to said lower limit inoperative position in response to a second electric signal.

21. Device as claimed in claim 14, characterized in that said sensor means (51 , 51") include a first electric proximity sensor (70) associated with said actuator means (10) to detect the position of the sprinkler (3) as it rotates, and a second electric proximity sensor (70') associated with said sprinkler (3) to detect the angular position (β) of the latter as it rocks.

22. Device as claimed in claim 21, characterized in that said valve means (51") include a first electrovalve (71) associated with said actuator means (10) and a second electrovalve (72) associated with a supply valve (57) for supplying fluid to said sprinkler (3), both of said electrovalves (71 , 72) having an input connected to said pressurized water supply line (L) and respective outputs designed to be selectively connected with said actuator means (10) or with said supply valve (57) or with a drain.

23. Device as claimed in claim 22, characterized in that said first and second electric proximity sensors (70, 70') and said first and said second solenoid valves

(71 , 72) are connected to a central microprocessor unit (77) having a timer (64).

24. Device as claimed in claim 23, characterized in that said microprocessor unit (77) is programmed to process electric signals from said sensors (70, 70') and sequentially control actuation of said solenoid valves (71 , 72), to first move said sprinkler (3) to said upper limit operative position and start water delivery in response to a first electric signal generated by said timer (64) and the stop water delivery and move said sprinkler (3) to said lower limit inoperative position in response to a second electric signal generated by said timer (64).