US3758038A

US3758038A - Hydraulically actuated rotary pop-up sprinkler

Info

Publication number: US3758038A
Application number: US00244836A
Authority: US
Inventors: H Ridgway
Original assignee: Telsco Ind
Current assignee: Telsco Ind
Priority date: 1972-04-17
Filing date: 1972-04-17
Publication date: 1973-09-11
Anticipated expiration: 1990-09-11

Abstract

Pop-up sprinklers are widely used in irrigation systems to provide watering over large areas. Pop-up sprinklers in such systems are power actuated into an extended position for a sprinkling cycle and are then power actuated into a retracted position upon completion of the sprinkling cycle. The power actuator includes a two chambered cylinder with the upper chamber separated into first and second regions by a piston movable with an axial tube that supplies water to the sprinkling head from a supply source. To power the sprinkler into an extended position, water at the supply pressure is directed into the second region of the upper chamber thereby lifting the piston and the attached supply tube. Upon completion of a sprinkling cycle, the second region of the upper chamber is vented to atmosphere and water at the supply pressure directed into the first region drives the piston down to retract the sprinkling head and close off the supply tube from the source of water supply.

Description

United States Patent [191 Ridgway 1 Sept. 11, 1973 HYDRAULICALLY ACTUATED ROTARY POP-UP SPRINKLER [75] Inventor:

[52] US. Cl; 239/206 [51] Int. Cl B05b 3/04 [58] Field of Search 239/201, 203,204,

[56] References Cited UNITED STATES PATENTS 1,484,888 2/1924 Johnson; 239/204 3,637,139 1/1972 Felix 239/206 Primary Examiner-Allen N. Knowles Attorney-J). Carl Richards et al.

[57] ABSTRACT Pop-up sprinklers are widely used in irrigation systems to provide watering over large areas. Pop-up sprinklers in'such systems are power actuated into an extended position fora sprinkling cycle and are then power actuated into a retracted position upon completion of the sprinkling cycle. The power actuator includes a two chambered cylinder with the upper chamber separated into-first and second regions by a. piston movable with an axial tube that supplies water to the sprinkling head from a supply source. To power the sprinkler into an extended position, water at the supply pressure is directed into the second region of. the upper chamber thereby lifting the piston and the attached supply tube. Upon completion of a sprinkling cycle, the second region of the upper chamber is vented to atmosphere and water at the supply pressure directed into the first region drives the piston down to retract the sprinkling head and close off the supply tube from the source of water supply.

20 Claims, 8 Drawing Figures Pmmansn'm 3,758,038

SHEET 1 BF 3 fllllllmi mammal: 1 ms I-IYDRAULICALLY ACTUATED ROTARY POP-UP. SPRINKLER This invention relates to an irrigation device, and

I more particularly to a pop-up sprinkler powered into up sprinkler heads, which retractout of sight when not in use, the chance of vandalism is markedly reduced. A further advantage of the pop-up sprinkler head is that it eliminates elevated obstructions which create hazardous conditions, particularly when concealed in high grass.

Heretofore, most pop-up sprinklers have been power driven into an extended position for the sprinkling cycle, but rely on the forces of gravity to retract the sprinkler into the concealed position. This arrangement has not proven satisfactory because the sprinkling head often failsto retract due to inadequate available force to overcome worn parts, friction, or obstruction by debris. One attempt to overcome the problem of pop-up sprinkler heads remaining in an extended position after a sprinkling cycle is to provide a retraction spring for lowering the sprinkling head. The retracting spring models also failed to properly retract again primarily due to inadequate available force.

To overcome the problem of pop-up sprinklers remaining in an extended position, it has been proposed to provide power actuation into the extended position and into the retracted position. To provide this, complicated water distribution systems have been proposed. While they perform the functions for which they were designed, namely power extension and power retraction of a sprinkling head, the complexity of the distribution system creates its own problems. Other suggested solutions to the problem of power drivingsprinklers into an extended and retracted position requires the venting of the power mechanism into the lawn area in such a manner that during certain portions of the extend/retract cycle debris and other foreign matter is inhaled into the operating mechanism. This not only tends to clog the exhaust tube, but also causes a buildup of debris within the operating mechanism thereby rapidly degrading required seals.

A feature of the present invention is to provide a power actuated pop-up sprinkler that eliminates inhaling to either extend or retract the sprinkling head. In completing the extend/retract operation, the power mechanism is exhausted to the atmosphere under a positive pressure thereby eliminating the inhaling of debris and other foreign matter into the mechanism.

In accordance with the present invention, an irrigation device comprises a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe. The cylindrical bore of the housing has an open upper end disposed near ground level with a first sealing gland in the upper end and a second sealing gland located below the top of said bore. A supply tube axially slides through the first and second glands thereby forming an upper and lower chamber in the cy' lindrical bore. In the upper chamber, a pistonmounted on the supply tube divides the chamber into a first region and a second region. A flow channel leading to the first region of the upper chamber provides water under pressure to the region to drive the supply tube and the sprinkler head downward. When the supply tube is driven downward, a seal closes the tube from flow of water from the supply pipe. A valve connected in a passage between the second region of the upper chamber and to water under pressure selectively connects the second region to the water pressure and atmosphere. With the valve means positioned to direct water under pressure into the second region of the upper chamber, a drive means is provided to initially extend the supply tube upward and unseal the same for flow through the sprinkler heads.

A more complete understanding of the invention and its advantages will be apparent from the specification and claims and from the accompanying drawings illustrative of the invention.

Referring to the drawings:

FIG. 1 is a side elevational view partially in section of a preferred configuration of an irrigation device in accordance with the present invention in a retracted or off position; y

FIG. 2 is a side elevational view of theembodiment of FIG. 1 showing the device in ain extended or on" position; i i i FIG. 3-is a side elevational view partially'in section showing an alternate embodiment of an irrigation device in the retracted or off position;

FIG. 4 is a side elevational view partially in section showing a modification of the irrigation device of FIG. 3 employing a closed end supply tube;

FIG. 5 is a side elevational view partially in section showing another modification of the irrigation device of FIG. 3 wherein an open tube is sealed by a slidable' seal in the retracted of position;

FIG. 6 is a side elevational view partially in section of the irrigation device of FIG. 5 showing the sprinkler supply pipe in an extended position;

FIG. 7 is a side view partially in section of an irrigation device with a control valving mechanism schematically shown connected thereto; and

FIG. 8 is a side view partially in section of still an-. other embodiment of an irrigation device in accordance with the present invention.

Referring to FIGS. 1 and 2, a pop-up sprinkler head has been illustrated in a preferred configuration. In this system, a buried water supply pipe 10 connects at its upper end to a threaded opening 11in a vertical housing 12. The housing 12 has a cylindrical bore 13 which may be continuous or, in the form shown, is provided with a larger portion chamber 13a. Near the upper end of the cylindrical bore 13, the housing assumes a conical shape with the flared portion 14 extending upward to acup-shaped section 15. The topof thesection 15 will normally be positioned at ground level or slightly below ground level.

A closure ring (gland) 16 is mounted in a further enlarged section 13b near the upper end of the cylindrical bore 13 and is provided with an outer O-ring 16a and an inner O-ring 16b. The outer ring 16a effects a liquid seal between the outer surface of the closure ring 16 and the inner surface of the enlarged section 13b. A central opening of the closure ring 16 provides a passage for an axially movable supply tube 20. The inner O-ring 16b effects a fluid seal between the outer surface of the supply tube 20 and the closure ring 16.

In the present form, the supply tube has a lower open end 21 bearing against a sealing washer 22. The sealing washer 22 is mounted on a central disc 23 which is supported at the lower end of the cylindrical bore 13 by a cylinder end 24 having a spoke-like configuration and thus providing a plurality of flow channels 25 for water from the supply pipe 10 to enter the cylindrical bore 13.

Mounted in the cylindrical bore 13, approximately midway its length, is a baffle gland 26 that divides the housing into an upper chamber and a lower chamber. An O-ring seal 27 effects a fluid seal between the baffle 26 and the outer surface of the supply tube 20. A cylindrical sleeve insert 28 having notches 32 is mounted in the upper end of the cylindrical bore, 13, specifically in the area of the larger diameter upper chamber 130. A flange on the baffle 26 serves as a seat for the lower end of the sleeve insert 28. An O-ring seal 29 effects a fluid seal between the baffle 26 and the sleeve insert 28. The baffle 26 rests upon a shoulder between the upper chamber 28a and a lower chamber 30. This shoulder is relieved at a plurality of points so that the water may flow from the lower chamber 30 through the passageways 31 to the annular chamber 28a outside the sleeve 28 and inside the upper chamber 13a through the notches 32.

Within the upper chamber 13a there is mounted to the supply tube 20 an annular member 33 (a piston). A seal between the outer wall of the annular member 33 and the inner wall of the insert 28 is provided by an O-ring seal 34. In this configuration, the annular member 33 divides the upper chamber 13a into a first region above the member 33 and a second region below the member 33. Within the lower region of the upper chamber 130 is a spring 35 between the lower surface of the annular member 33 and the upper surface of the baffle 26. This spring provides an upward directing force to the supply tube 20 when the sprinkler is in an off" position.

A three-way valve is coupled by way of a pipe 41 to the second region of the upper chamber 13a between baffle 26 and the annular member 33 and by a pipe 42 to the lower chamber 30. The three-way valve 40 is also coupled by a pipe 43 to the region inside the cone 14 which is at atmospheric pressure.

Above the closure ring 16, the supply tube 20 terminates in an open end 44 onto which is assembled a freely rotating sprinkler head 46. The sprinkling head 46 may be any one of many well-known types having a nozzle 47 for discharging a water spray 48 (see FIG. 2) and which causes the head to rotate by impingement of a secondary water stream 49 from a nozzle 50 against a reaction member 51. According to the usual construction of such sprinkling heads, the reaction member 51 is biased by means of a spring 52.

When in a retractedposition as shown in FIG. 1, the sprinkling head 46 is stowed within the cup-shaped section 15 and carries an enclosure disc 53 that males with the section 15 to form a protective enclosure for the sprinkling head 46.

In operation, in the position illustrated in FIG. 1, the lower end of the supply tube 20 is sealed against the sealing washer 22 by a force produced by the water pressure on the inside of the insert 28 exerted against the annular member 33 and overcoming the force of the spring 35. In this position, the three-way valve 40 exhausts the second region of the upper chamber 13a i to the atmosphere through the pipe 43. When the irrigation device is to be placed in operation for a sprinkling cycle, the rotary valve core of the three-way valve 40 is rotated to the position shown in FIG. 2 to apply the water pressure in the supply pipe 10 to the region between baffle 26 and annular member 33. This equalizes the pressure above and below the annular member 33 and the force produced by the spring 35 lifts the supply tube 20 upward enough to unseat the lower end from the sealing washer '22. This permits water to flow up through the supply tube 20 and out of the

nozzles

47 and 50 of the sprinkling head 46. Water' pressure on the lower end of the supply tube 20 and the additional pressure exerted within the tube 20 by means of water back pressure at the head 46 will drive the tube 20 up into an extended position until the upper surface of the annular member 33 seats against the lower surface of the closure ring 16.

When the sprinkler is to be turned off and retracted, the valve core of the three-way valve 40 is rotated to the position shown in FIG. 1 venting the region below the annular member 33 to atmosphere through the pipe 43. With the valve 40 thus positioned, water pressure exerting a downward force on the upper surface of the annular member 33 forces water out of the second region, through the exhaust pipe 43 and drives the supply tube 20 downward overcoming the spring 35 until the lower end 21 rests on the sealing washer 22. The sprinkler head 46 is now stowed within the enclosure formed by the section 15 and the disc 53. V

It is important to note that water at the supply pressure is maintained above the annular member 33 at all times. The region below the annular member 33 and above the baffle 26 is selectively maintained at thesupply pressure and at atmospheric pressure to effect oper' ation without permitting suction into the system of any debris or foreign matter byway of pipe 43. The flow through pipe 43 is always required to be in one direction, away from the control system.

Referring now to FIG. 3, there is shown an alternate embodiment of an irrigation device in accordance with the present invention wherein like reference numerals designate like parts. A water supply pipe 10 having an externally threaded section connects to an internally threaded section of a housing 12 having a cylindrical bore 13 divided into an upper chamber 13a and a lower chamber 30 by means of a divider 60. Near the upper end of the cylindrical bore 13, the housing assumes a conical shape with the flared portion 14 extending upward to a cup-shaped section 15. A closure ring 16 is mounted in an enlarged section 13b near the upper end of the cylindrical bore 13 and is'provided with an outer O-ring 16a and an inner O-ring 16b. A central opening of the closure ring 16 provides a passage for an axially movable supply tube 20- with the inner O-ring 16b providing a fluid seal.

As in the embodiment of FIGS. 1 and 2, the supply tube 20 has a lower open end 21 bearing against a sealing washer 22 with the washer mounted on a central disc 23 supported at the lower end of the cylindrical bore 13 by a cylinder end 24 having a spoke-like configuration and providing a plurality of flow channels 25 for water from the pipe 10.

Within the upper chamber 13a there is mounted to the supply tube 20 an annular member 33 (a piston). The annular member 33 divides the upper chamber 13a into a first region above the member 33 and a second region below the member 33. Within the lower region of the upper chamber 13a is a spring 35 for biasing the member 33 man upward direction. 7

Above the closure ring 16, the supply tube 20 terminates in an open end 44 onto which is assembled a freely rotating sprinkler head 46. When in a retracted position, as shown in FIG. 3, the sprinkling head 46 is stowed within the cup-shaped section and carries an enclosure disc that mates with the section to form a protective enclosure therefor.

Opening within the lower chamber 30 is a flow channel 62 having a first section 6211 extending to an opening'within the first region of the upper chamber 13a. A second flow channel 63 opens into the channel 62 and terminates at a three-way control valve 40 coupled by way of a pipe 41 to the second region of the upper chamber 13a. The three-way valve 40 is also coupled by a pipe 43 to the region inside the cone 14 which is at atmospheric pressure.-

Operation of the embodiment of FIG. 3 is similar to that described in connection with the preferred embodiment of FIGS. 1 and 2. Water at the pressure within the supply pipe 10 enters the lower chamber 30 through the passages 25 and enters the first region of the upper chamber 13a through the

flow channels

62 and 62a. With the three-way valve 40 in the position illustrated in FIG. 3, the second region of the chamber 13a is open to atmosphere with pressure within the second region being at' the atmospheric level. A force developed by water pressure within the first region of the chamber 13a as exerted on the annular member 33 forces the supply tube 20 into a sealing engagement against the sealing washer 22. Forces generated within the first region of the chamber 13a are sufficient to overcome a force produced by the spring 35. As illustrated, the sprinkler head 46 is in a stowed position at, or slightly below, ground level.

During a sprinkling cycle, the core of the three-way valve 40 is rotated into its second position (as shown in FIG. 2) thereby allowing water at the pressure within the lower chamber to enter the second region of the upper chamber 13a. Forces developed by water pressure within both the first region and the second region of the chamber 13a are now equal and oppositely ap plied. Since the spring 35 adds an additional force upward against the annular member 33, the supply tube 20 is lifted upward thereby exposing the opening to water within the lower chamber 30. Water within the lower chamber 30 enters the supply pipe 20 and is dis charged through the sprinkler head 46 in the manner as illustrated in FIG. 2. Water pressure exerted on the lower section of the tube 20 and a backpressure developedat the sprinkler head 46 within the supply tube 20 provides the extending force to lift the sprinkler into an on:' and extended position. A

At the completion of a sprinkling cycle, the core of the three-wayvalve 40 is again rotated to exhaust the second region of the chamber 13a to atmosphere through the pipe 43. Again the fluid in the region below the annular member 33 is selectively maintained at the supply pressure or at atmospheric pressure to effect operation without inhaling into the system debris or foreign matter through the pipe 43. By exposing the second region of the chamber 13a to atmospheric pressure, the pressure within the first region drives the annular member 33 and the supply tube 20 downward forcing water out of the second region through the exhaust pipe 43 and overcoming the spring 35 until the supply tube is seated and sealed by the washer 22.

Referring to FIG. 4, there is shown a modification of the irrigation device of FIG. 3 wherein like reference numerals designate like parts. The modification of FIG. 4 lies in the area of the supply tube 20 and the connection of the flow channel 62 to water pressure within the supply pipe 10. The water supply pipe 10 has an externally threaded section that connects with an internally threaded section of a housing 12 having a cylindrical bore 13 divided into an upper chamber 13a and a lower chamber 30 by'means of a divider 60. Above the end of the supply pipe 10,-within the housing 12, there is a riser area having an outlet connected to the flow channel 62.

Through the center of the lower end of the housing 12 there is a passage 72 for permitting water to flow from the supply pipe 10 into the lower chamber 30. With the sprinkler head 46 in a retracted position, the supply tube 20 is in its lowest position thereby causing the riser area 70 to be sealed by means of a washer 74 riveted or otherwise attached to the closed .end 76 of the supply tube. V

To actuate the sprinkler head 46 into its extended and retracted positions, the flow channel 62' connects to a three-way valve 40 and also by means of a flow channel 62a tothe first region of the chamber 13a. Also connected to the three-way valve 40 is a pipe 41 from the second region of the chamber 13a. An exhaust pipe 43 connects to.the three-way valve 40 and has one end opened to atmosphere through the flared portion 14.

Operation of the embodiment of FIG. 4 is similar to that described with reference to FIG. 3. Water at the pressure within the supply pipe 10 enters the flow channel 62 and through the flow channel 62a into the first region of the upper chamber 13a. With the three-way valve 40 in the position illustrated in FIG. 4, the second region of the upper chamber 13a is open to atmosphere and pressure within the second region is at atmospheric. Forces developed by water pressure within the first region of the upper chamber 13a are exerted on the annular member 33 to drive the supply tube 20 downward and forcing the sealing washer 74 into engagement with the lower end of the housing 12 to seal off the chamber 30 from water pressure within the supply pipe 10.

During a sprinkling cycle, the core of the three-way valve 40 is rotated into its second position (as shown in FIG. 2) thereby allowing water at. the pressure within the riser area 70 to enter the second region of the upper chamber 13a through the flow channel 62. Forces developed by water pressure within both the first region and the second region of the chamber 13a are now equal andoppositely applied. However, water pressure within the passage 72 exerts an upward-force on the sealing washer 74to provide a net positive or extending force, and the supply tube 20 is driven upward thereby opening the passage 72 to allow water to flow. into the lower chamber 30. Water within the lower chamber 30 enters the supply tube 20 through passages 78 and is discharged through the sprinkler head 46 in the manner as illustrated in FIG. 2. Waterpressure exerted on the sealing washer 74 and a back pressure developed at the sprinkler head 46 within the supply tube 20 now provides the extending force to lift the sprinkler into a fully on and extended position.

At the completion of a sprinkling cycle, the core of the three-way valve 40 is again rotated to exhaust the second region of the chamber 13a to atmosphere through the exhaust pipe 43. Again the fluid in the region below the annular member 33 is selectively maintained at the supply pressure or at atmospheric pressure to effect operation without inhaling into the system debris or other foreign matter through the exhaust pipe 43. By exposing the second region of the chamber 13a to atmospheric pressure, pressure within the first region drives the annular member 33 and the supply tube 20 downward forcing water out of the second region through the exhaust pipe 43, overcoming the force exerted on the sealing washer 74 until the chamber 30 is sealed from the supply pipe 10.

Referring to FIG. 5, there is shown another modification of the irrigation device of FIG. 3 wherein like reference numerals are used for like parts. Within the lower chamber 30 of the housing 12, water is received from the supply pipe 10 through flow channels 25 around the central disc 23 of the cylinder end 24.

Threadedly secured to the central disc 23 within the chamber 30 is a guide rod 80 having a retaining ring 82 affixed to the upper end thereof. Slidably mounted on the guide rod 80 is a slidable seal 84 having a through passage 86. Also mounted on the guide rod 80 is a spring 81.

As in the embodiment of FIG. 3, the supply tube 20 has a lower open end 2] bearing against the slidable seal 84. With the supply tube 20 in the position shown in FIG. 5, water within the chamber 30 is sealed from entering the supply tube.

Referring to FIGS. 5 and 6, operation of the embodiment shown is similar to that described with reference to the irrigation device of FIG. 3. Water at the pressure within the supply pipe enters the lower chamber 30 through the passages 25 and enters the first region of the upper chamber 13a through the

flow channels

62 and 62a. With the three-way valve 40 in the position illustrated in FIG. 5, the second region of the chamber 13a is open to atmosphere and pressure within the second region is at atmospheric. Forces developed by water pressure within the first region of the chamber 13a are exerted on the annular member 33 to drive the supply tube into a sealing engagement with the seal 84 and the central disc 23 seals the passage 86.

To extend the sprinkler 46 into the position illustrated in FIG. 6, the core of the three-way valve 40 is rotated into its second position thereby allowing water at the pressure within the lower chamber 30 to enter the second region of the upper chamber 13a, as explained previously. Forces developed by'water pressure within'both the first and second regions of the chamber 13a are now equal and oppositely applied. Water pressure'exerting a force on the slidable seal 84 will provide a net upward effect thereby applying a lifting force to the lower end of the supply tube 20 and lifting the tube upward. As the ball seal 84 reaches its upward travel limit as determined by the spring 81 and the retaining ring 82, water pressure exerted on the lower cross section of the supply tube 20 continues to extend the sprinkler 46. As the tube starts to move away from the seal 84, pressure within the chamber 30 is reduced by the leakage. The upward force on the seal 84, exerted by the fluid pressure, is thereby reduced causing the spring 81 to force the seal 84 down. The friction forces and pressure on the end of the tube end 21 will not allow the tube 20 to come down, so the tube 20 and the seal 84 are separated causing a lower pressure in the chamber 30 and higher flow and back pressure in the tube 20 causing it to move up to the fully extended on" position.

At the completion of a sprinkling cycle, the core of the three-way valve 40 is again rotated to exhaust the second region of the chamber 13a to atmosphere through the exhaust pipe 43. Fluid in the region below the annular member 33 is selectively maintained at supply pressure or at atmospheric pressure to effect operation without inhaling into the system debris or foreign matter through the exhaust pipe 43. By exposing the second region of the chamber 13a to atmospheric pressure, the pressure within the first region drives the annular member 33 and the supply tube 20 downward forcing water out of the second region through the exhaust pipe until the supply tube again makes contact with the ball seal 84. Forces exerted by pressure within the first region of the upper chamber 13a are sufficient to overcome the upward exerted forces on the ball seal 84 to drive the supply tube into the fully retracted position and the passage 86 is sealed against the central disc 23.

Referring to FIG. 7, there is shown a further modification of an irrigation device in accordance with the present invention. This device is similar to that illustrated in FIG. 3 with a modification of the control valving. A two-position four-way valve provides the reversal of atmospheric and supply pressure across the annular member 33 by selectively connecting one region to the supply pressure through pipe 71 and the other region to atmosphere through the exhaust pipe 43. In the position illustrated, a pipe 71 terminates within the lower chamber 30 and a pipe 72, terminating in the first region of the upper chamber 13a, provides a flow channel for water delivered from the supply pipe 10 through the passages 25. A pipe 73 terminates within the second region of the chamber 13a to provide an exhaust channel through the valve 70 and the pipe 43.

With conditions as illustrated in FIG. 7, a pressure within the first region of the chamber 13a provides a downward exerted force against annular member 33 to overcome any upward exerted forces to close off the supply tube 20 from water within the chamber 30 by sealing against the sealing washer 22. To extend the sprinkler head 46 into an on position, the core of the four-way valve 70 rotated to apply pressure to the second region and to allow the first region to exhaust through the exhaust pipe 43. The annular member 33 and the supply tube 20 are moved upward to extend the sprinkling head 46 into a sprinkling position. As the annular member 33 moves upward, it forces water from the first region of the upper chamber 13a through the valve 70. and the pipe 43. Note, that there is a positive discharge through the pipe 43 and not an inhaling action.

To retract the sprinkling head 46 into a stowed position, the core of the four-way valve 70 is rotated 90 to the position shown in FIG. 7. Water from the lower chamber 30 is now allowed to flow into the first region of the upper chamber 13a through the

pipes

71 and 72.

Water within the second region of the upper chamber 13a is exhausted to atmosphere through the

pipes

43 and 73. Again, a positive discharge takes place thereby preventing the inhaling of foreign matter and other debris into the working mechanism of the irrigation device while the supply tube 20 moves downward to cut off the flow through the sprinkler head 46.

Referring to FIG. 8, there is shown another embodiment of the irrigation device illustrated in FIG. 3. Water within the lower chamber 30 of the housing 12 enters the first region of the upper chamber 13a through a flow channel consisting of a pipe 62. In this embodiment, the first region of the upper chamber 13a is formed by an annular member 33 attached to a supply tube 75. The supply tube 75 has a first external diameter for a lower section thereof smaller than a second external diameter at the upper section. This change in diameter provides the smaller surface area of the annular member 33 exposed to water pressure in the first region of the upper chamber 13a than in the second region of this chamber. As a result, if water at the same pressure is supplied to both the first region and the second region of the upper chamber 13a a greater force is exerted ,in an upward direction against the annular member 33 thereby raising the supply tube 75 from a sealing engagement with the sealing washer 22, and the sprinkler head 46 is extendedinto a sprinkling position.

To extend the sprinkler head 46 into a sprinkling condition with the irrigation device of FIG. 8, the core of the three-way valve 40 is moved into the position illustrated in FIG. 2. Water at the pressure of the supply pipe flows through the pipe 62 into the first region of the upper chamber 13a and also flows through the pipe 63 into the second region of the upper chamber. Because of the difference in effective surface area on opposite sides of the annular member 33, a greater force is exerted upward thereby extending the sprinkler head 46. Water flows through the lower chamber 30 into the supply tube 75 and out through the sprinkler head 46. An additional extending force is produced by the pressure exerted on the lower end of the supply tube 75 and by the back pressure within the sprinkler head 46.

At the completion of a sprinkling cycle, the core of the three-way valve 40 is turned into the position illustrated in FIG. 8 thereby opening the second region of the upper chamber 13a to atmospheric pressure through the pipe 43. Water within the first region of the chamber 13a is still at the supply pressure and exerts a downward moving force against the annular member 33. With the second region exhausted to the atmosphere a net downward force is exerted on the supply tube 75 driving the sprinkler head 46 into the off and retracted position. Again, during the retraction motion of the powered actuator, a positive discharge-takes place through the pipe 43 thereby eliminating the inhaling of foreign matter of other debris into the second region of the chamber 13a. i

While several embodiments of the invention, together with modifications thereof, have been described in detail herein and shown in the accompanying drawings, it will be evident that various further modifications are possible without departing from the scope of the invention.

What is claimed is:

1. An irrigation device comprising:

a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe, having an open upper end disposed near ground level with a first sealing gland in the upper end thereof and a second sealing gland located below the top of said bore, a supply tube axially slidable through said glands in a sealing engagement therewith, a sprinkler head mounted on the top of said tube above said glands, an annular member mounted on said tube in said bore above said second gland and below said first gland having a seal cooperating with said bore to control flow of water around said annular member, a flow channel leading to a first region of said bore between said first gland and said annular member for flow of water to said first region at a pressure to drive said tube downward, sealing means to close said supply tube from flow of water from the supply pipe when said tube is driven downward in said housing, valve means for selectively connecting a second region of said bore located between said second gland and said annular member to water under pressure and to atmosphere, and means operable when water pressure is applied to said second region to drive said supply tube upward and unseal the same for flow through said tube. 2. An irrigation device as set forth in claim 1 wherein said cylindrical bore has a first chamber between the second gland and the bottom end of said housing and a second chamber between the first and second sealing glands and passages between said first and second chambers around said second glands, and

said flow channel includes a sleeve between the first and second glands in the upper chamber and having bypass notches for directing water into the first region. 7 3. An irrigation device as set forth in claim 1 wherein said cylindrical bore includes at least one passage at the bottom end for opening a lower chamber between the.

bottom end and the second gland to water in the supply pipe.

4. An irrigation device as set forth in claim 3 wherein said flow channel includes a pipe with one end opening to receive water from the water supply pipe and having a second end opening into the first region, and

said valve means selectively connects the second region to water in said pipe and to the atmosphere.

5. An irrigation device as set forth in claim 1 wherein said means operable when water at said pressure is applied to said second region to drive said supply tube upward includes a spring positioned between the second sealing gland and said annular member in the second region.

6. An irrigation device as set forth in claim 1 wherein said sealing means includes a slidable seal on a guide attached to said housing for movement along said guide to close the supply tube from flow of water through the supply tube. a a

7. An irrigation device as set forth in claim 1 wherein said supply tube includes passages for admitting water from a chamber in said housing below the second sealing gland and the bottom end to said sprinkler head.

8. An irrigation device comprising:

a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe, having an open upper end disposed near ground level with a first sealing gland in the upper end thereof and a second sealing gland located below the top of said bore,

a supply tube axially slidable through said gland in a sealing engagement therewith,

a sprinkler head mounted on the top of said tube above said glands,

an annular member mounted on said tube in said bore above said second gland'and below said first gland and having a seal cooperating with said bore to control flow of water around said annular memher,

a first flow channel leading to a first region of said bore between said first gland and v said annular member for flow of water to said first region at a pressure to drive said tube downward,

sealing means to close said supply tube from flow of water from the supply pipe when said tube is driven downward in said housing,

a second flow channel leading to a second region of said bore located between the second gland and said annular member and to water under pressure from the supply pipe,

valve means located in said second channel to selectively connect the second region to the water from the supply pipe and to atmosphere, and

means operable when water pressure is applied to said second region to drive said supply tube upward and unseal the same for flow through said supply tube.

9. An irrigation device as set forth in claim 8 including second valve means located in said first flow channel to selectively connect the first region to water pressure and to the atmosphere.

10. An irrigation device as set forth in claim 9 wherein said first and second valve means comprises a two-position valve wherein in one position water is supplied to the first region and the second region is exhausted to the atmosphere and in a second position water pressure is supplied to the second region and the first region is exhausted to the atmosphere.

1]. An irrigation device as set forth in claim 10 wherein said cylindrical bore includes at least one passage at the bottom end for opening a lower chamber between the bottom and the second gland to water in the supply pipe.

12. An irrigation device as set forth in claim 11 wherein said flow channels include a first pipe with one end opening to water in the supply pipe and having a second end connected to said two-position valve, a second pipe having one end connected to the two-position valve and a second end opening into the second region, and a third pipe having one end connected to the twoposition valve and a second end opening into the first region of said housing.

13. An irrigation device as set forth in claim 8 wherein said sealing means includes a slidable seal on a guide attached to said housing for movement along said guide to close the supply tube from flow of water through the supply tube.

14. An irrigation device as set forth in claim 8 wherein said supply tube includes passages for admitting water from a chamber in said housing below the second sealing gland and the bottom end to said sprinkler head.

15. An irrigation device comprising:

a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe,

having an open upper end disposed near ground level with a first sealing gland in the upper end thereof and a second sealing gland located below the top of said bore,

a supply tube axially slidable through said glands in a sealing engagement therewith and having a first section of one external diameter terminating in said bore above said second gland and a second section of a larger external diameter extending'from said first section up through said first sealing gland,

a sprinkler head mounted on the top of said tube above said glands,

an annular member mounted on said tube in said bore above said second sealing gland and below said first sealing gland and having a seal cooperating with said bore to control flow of water around said annular member,

a flow channel leading to a first region of said bore between said first gland and said annular member for flow of water to said first region at a pressure to drive said tube downward,

sealing means to close said supply tube from flow 0 water from the supply tube when said tube is driven downward in said housing, and

valve means for selectively connecting a second region of said bore located between said second gland and said annular member to water under pressure from said supply pipe and to atmosphere.

16. An irrigation device as set forth in claim 15 wherein said cylindrical bore has a first chamber between the second gland and the bottom end of the cylinder and a second chamber below the first gland and above the second gland and passages between said first and second chambers around said second gland, and

said flow channel includes a sleeve between the first and second glands in the second chamber and having bypass notches for directing water into the first region. 7

17. An irrigation device as set forth in claim 15 wherein said cylindrical bore includes at least one passage at the bottom end for opening a lower chamber between the bottom end and the second gland to water in the supply pipe.

18. An irrigation device as set forth in claim 17 wherein said flow channel includes a pipe with one end opening to receive water from the supply pipe and having a second end opening to the first region, and

19. An irrigation device as set forth in claim 15 wherein said sealing means includes a slidable seal on a guide rod attached to said housing for movement along said guide to close the supply tube from flow of water through the supply tube.

20. An irrigation device as set forth in claim 15 wherein said supply tube includes passages for admitting water from a chamber in said housing below the second sealing gland and the bottom end to said sprinkler head.

i -e rs:

Claims

1. An irrigation device comprising: a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe, having an open upper end disposed near ground level with a first sealing gland in the upper end thereof and a second sealing gland located below the top of said bore, a supply tube axially slidable through said glands in a sealing engagement therewith, a sprinkler head mounted on the top of said tube above said glands, an annular member mounted on said tube in said bore above said second gland and below said first gland having a seal cooperating with said bore to control flow of water around said annular member, a flow channel leading to a first region of said bore between said first gland and said annular member for flow of water to said first region at a pressure to drive said tube downward, sealing means to close said supply tube from flow of water from the supply pipe when said tube is driven downward in said housing, valve means for selectively connecting a second region of said bore located between said second gland and said annular member to water under pressure and to atmosphere, and means operable when water pressure is applied to said second region to drive said supply tube upward and unseal the same for flow through said tube.

2. An irrigation device as set forth in claim 1 wherein said cylindrical bore has a first chamber between the second gland and the bottom end of said housing and a second chamber between the first and second sealing glands and passages between said first and second chambers around said second glands, and said flow channel includes a sleeve between the first and second glands in the upper chamber and having bypass notches for directing water into the first region.

3. An irrigation device as set forth in claim 1 wherein said cylindrical bore includes at least one passage at the bottom end for opening a lower chamber between the bottom end and the second gland to water in the supply pipe.

4. An irrigation device as set forth in claim 3 wherein said flow channel includes a pipe with one end opening to receive water from the water supply pipe and having a second end opening into the first region, and said valve means selectively connects the second region to water in said pipe and to the atmosphere.

6. An irrigation device as set forth in claim 1 wherein said sealing means includes a slidable seal on a guide attached to said housing for movement along said guide to close the supply tube from flow of water through the supply tube.

8. An irrigation device comprising: a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe, having an open upper end disposed near grouNd level with a first sealing gland in the upper end thereof and a second sealing gland located below the top of said bore, a supply tube axially slidable through said gland in a sealing engagement therewith, a sprinkler head mounted on the top of said tube above said glands, an annular member mounted on said tube in said bore above said second gland and below said first gland and having a seal cooperating with said bore to control flow of water around said annular member, a first flow channel leading to a first region of said bore between said first gland and said annular member for flow of water to said first region at a pressure to drive said tube downward, sealing means to close said supply tube from flow of water from the supply pipe when said tube is driven downward in said housing, a second flow channel leading to a second region of said bore located between the second gland and said annular member and to water under pressure from the supply pipe, valve means located in said second channel to selectively connect the second region to the water from the supply pipe and to atmosphere, and means operable when water pressure is applied to said second region to drive said supply tube upward and unseal the same for flow through said supply tube.

11. An irrigation device as set forth in claim 10 wherein said cylindrical bore includes at least one passage at the bottom end for opening a lower chamber between the bottom and the second gland to water in the supply pipe.

12. An irrigation device as set forth in claim 11 wherein said flow channels include a first pipe with one end opening to water in the supply pipe and having a second end connected to said two-position valve, a second pipe having one end connected to the two-position valve and a second end opening into the second region, and a third pipe having one end connected to the two-position valve and a second end opening into the first region of said housing.

15. An irrigation device comprising: a housing having a cylindrical bore closable at the bottom end by attachment to a water supply pipe, having an open upper end disposed near ground level with a first sealing gland in the upper end thereof and a second sealing gland located below the top of said bore, a supply tube axially slidable through said glands in a sealing engagement therewith and having a first section of one external diameter terminating in said bore above said second gland and a second section of a larger external diameter extending from said first section up through said first sealing gland, a sprinkler head mounted on the top of said tube above said glands, an annular member mounted on said tube in said bore above said second sealing gland and below said first sealing gland and having a seal cooperating with said bore to control flow of water around said annular member, a flow channel leading to a first region of said bore between said first gland and said annular member for floW of water to said first region at a pressure to drive said tube downward, sealing means to close said supply tube from flow of water from the supply tube when said tube is driven downward in said housing, and valve means for selectively connecting a second region of said bore located between said second gland and said annular member to water under pressure from said supply pipe and to atmosphere.

16. An irrigation device as set forth in claim 15 wherein said cylindrical bore has a first chamber between the second gland and the bottom end of the cylinder and a second chamber below the first gland and above the second gland and passages between said first and second chambers around said second gland, and said flow channel includes a sleeve between the first and second glands in the second chamber and having bypass notches for directing water into the first region.

18. An irrigation device as set forth in claim 17 wherein said flow channel includes a pipe with one end opening to receive water from the supply pipe and having a second end opening to the first region, and said valve means selectively connects the second region to water in said pipe and to the atmosphere.