US3891148A

US3891148A - Spray device

Info

Publication number: US3891148A
Application number: US441360A
Authority: US
Inventors: Gilles Rousseau
Original assignee: Patrick Harrison and Co Ltd
Current assignee: Patrick Harrison and Co Ltd
Priority date: 1974-02-11
Filing date: 1974-02-11
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24

Abstract

This invention relates to a device for spraying water with an automatic shut off comprising a body, a nozzle, a first passage through said body terminating at said nozzle through which water can be sprayed, closure means for said first passage operable between an open position which permits flow through said first passage and a closed position which stops flow through said first passage, a pressure chamber in said body, said closure means being responsive to the build up of fluid pressure in said pressure chamber to move to said closed position, means responsive to the flow of water through said first passage to build up pressure in said pressure chamber over a predetermined period of flow time.

Description

United States Patent Rousseau June 24, 1975 SPRAY DEVICE Primary Examiner-Lloyd L. King [75] Inventor: Gilles Rousseau, North Bay, Canada Attorney Agent or Flrm petherstonhaugh &

[73] Assignee: Patrick Harrison & Company Limited, Toronto, Canada [57] ABSTRACT Filed: 11, 1974 This invention relates to a device for spraying water [21] APPL NO; 441,360 with an automatic shut off comprising a body, a nozzle, a first passage through said body terminating at said nozzle through which water can be sprayed, clo- [52] US. Cl. 239/68 Sure means for said first passage Operable between an [51] Int. Cl AOlg 27/00 Open position Which permits flow through said fi [58] Field of Search 239/67, 68, 69; 137/67; passage and a closed position which Stops fl 251/50 51; 222/57 67, 14; 251/54 through said first passage, a pressure chamber in said body, said closure means being responsive to the build References Cited up of fluid pressure in said pressure chamber to move UNITED STATES PATENTS to said closed position, means responsive to the flow 1,831,007 11/1931 Johnson 239/67 of Water through Said first P g to build p Pressure 2,878,824 3/ I959 Swanson 239/67 in said pressure chamber over a predetermined period 2,928,606 3/]960 Lee 239/67 Of flow time. 3,089,651 5/1963 Skerritt 239/68 7 Claims, 4 Drawing Figures 1 SPRAY DEVICE This invention relates to a device for spraying water and air at underground locations in a mine.

In an underground mining operation, it is necessary to lay the dust and gas that result from blasting in headings and stopes by spraying air and water for a predetermined period of time after the blasting operation.

At the present time, the procedures for dispelling dust and gas in headings and stopes are simply that air and water are turned on and sprayed on the muck pile. The air and water are turned on prior to the blasting and left running until someone comes back into the working place and shuts both air and water off. Under most mining conditions, it is not practical to have a man return to the site within a reasonable amount of time after the blast so that in most cases, the spraying operation continues for a very much longer period of time than is necessary. This procedure is both expensive and dangerous.

The use of compressed air underground for any means is expensive because energy must be used on the surface to compress the air and transport it through the headers to the working place. Water is not as expensive to transport to a working location underground, but it also becomes expensive underground because it must eventually be pumped back to the surface. Moreover, water in excess amounts can wash fill from the stopes down onto the drift floors. This must be cleared away and the cost of labour for clearing the drift floors of water can be very high.

It is, therefore, an object of the present invention to provide a device capable of spraying air and water following a blast in a mine that will spray water for a controlled and predetermined period of time and then automatically shutting off.

It is a further object of the invention to provide such a device that is simple and that can be used with reliability under conditions encountered in mining.

With these and other objects in view, a device for spraying water with air according to this invention comprises a body, a nozzle, a first passage through said body terminating at said nozzle through which water can be sprayed, closure means for said first passage operable between an open position which permits flow through said nozzle and a closed-position which stops flow through said nozzle, a pressure chamber in said body, said closure means being responsive to build up of pressure to a predetermined value in said pressure chamber to move to said closedposition, means, responsive to the flow of water through said first passage to build up pressure in said pressure chamber over a predetermined period of flow time.

The invention will be clearly understood after reference to the following detailed specification read in conjunction with the drawings.

air and water that begins at the fitting 12, extends through bore 14 in aluminum block 16 and terminates in nozzle 18. In use, as will be explained later, a mixture of water and air from

pressure supply lines

20 and 22 respectively is forced through the passage and out the nozzle to lay dust and clear the air after a blast in a mine. Water and air are mixed to form a water spray in standard mine spraying practice and detailed reference to this aspect is not made in this application.

The purpose of this invention is to provide a simple and reliable means suitable for use under conditions of mine operation for shutting off the flow of water and air through the passage after a predetermined time. This is effected by means of a closure for the passage that is responsive to the build-up of pressure in a pressure chamber to move from a normally open position to a closed position in the passage.

In the embodiment of the invention illustrated, the closure means is a piston 14, the back end of which is rigidly connected to an end of spring 26. The piston is reciprocable within block 16 and is held in the normally open position illustrated in FIG. 3 by means of a spring 26, the second end of which connects with stem 28.

Stem 28 is in turn supported by the nut 30 that threadedly engages with the enlarged back portion of the bore within which piston 24 reciprocates. Stem 28 threadedly engages in nut 30 and is locked in any desired position by the locking nut 32. The free end of the stem 28 acts as a stop to limit the rearward travel of the piston.

The piston 24 has a pair of double rubber cylinder cups 30 at its back end, the marginal portions of which seal with the enlarged diameter of the bore as illustrated to seal the piston hydraulically with respect to the sides of the bore. They are secured to the piston by bolt 31.

Thus, under normal conditions, the spring 26in its relaxed position maintains the piston 24 with the front end thereof just within the passage 14, and while the device is spraying water and air, the water and air pass the free smaller end of the piston 24 as illustrated in FIG. 3. As will be referred to later, the piston does, in operation, move from its normal position illustrated in FIG. 3 toa closed position illustrated in FIG. 4 where the front end thereof seats in the nozzle 18 to close off the passage through the aluminum block 16.

The piston 24 is triggered from its open position, illustrated in FIG. 3, to its closed position, illustrated in FIG. 4, by means of the build up of water pressure within the chamber 36. Chamber 36 is hydraulically connected with the enlarged rear portion of the bore within which cylinder 24 reciprocates and the build up of the pressure acting on the seals 30 actuates the piston forward as will be explained later.

Chamber 36 connects with the rear portion of the piston slideway through pipe 38 and passage 40 in the aluminum block 16. Chamber 36 is also hydraulically connected to the passage through the block 16 by passage 42, passage 40 and fitting 38.

A tap 44 at the bottom of chamber 36 can be opened to drain the chamber prior to commencement of use. In use, the tap 44 is opened and chamber 36 is drained. Tap 44 is then closed to seal the lower portion of the chamber. As water and air passes through the passage 14 and out the nozzle 18, a certain amount is bled off through passage 42 and passage 40 and fitting 38 to the chamber 36. The bled off portion of the water accumulates in chamber 36 and as it does so, air evacuates through the vent opening 45 in the top of the chamber. Vent opening 44 has a ball valve 46 that is normally supported on a screen 48 so that air can pass freely through opening 46 as the chamber fills. When, however, the chamber fills above the level of the screen, the ball 46 floats upwardly on the rising liquid level to close off the air vent 44 with the result that the addition of further water through the passage 42 to the chamber 36 results in a back-up of water through fitting 38 and passage 40 to the back end of the piston and an eventual build up of pressure that eventually acts on the back end of the piston 25 to move it forward. It will be noted that the back end of the piston 24 is larger than the front end and the total pressure on the back end readily overcomes the retaining or positioning effect of the spring 26 with the result that the piston 24 moves forward to seal in the nozzle and close the passage for water through the nozzle as illustrated in FIG. 4.

In this connection, there is probably a venturi effect on the forward end of the piston 24 that tends to reduce the pressure on the forward end as the closing progresses. In any event, the action of closure is a very sudden and positive one.

Once closed as a result of the build up of pressure in the chamber 36, the flow of water stops untilthe device is reset.

While spring 26 is desirable for the purpose of returning the piston to its normal position against the end of rod 28, it is not necessary. Upon draining of the tank and reactivating of the air and water supply, there is enough leakage pressure from passage 14 against the front end of the washer to return the piston to its normal position and permit spraying until the activating pressure again builds up in the chamber 36.

The flow of water through passage 22 is controllable as to flow rate by manipulation of the needle valve 50. Needle valve 50 has a stem that is threadedly mounted in the block 16 and can be advanced or withdrawn to decrease or increase the flow rate through the passage By manipulation of the needle valve 50, the time within which the pressure is built up to automatically shut off the flow of air and water through the nozzle can readily be varied between minutes and 3 hours using a tank or chamber 36 with a capacity of about 1 gallon.

In order to reset the device, one merely turns off the air and water supply at the source and opens the draining valve 44. As this occurs, the tank 36 drains and spring 26 moves the piston 24 to its open position where it floats until further actuated under conditions where it automatically shuts off the air and water supply after a predetermined period of operation. The air supply 22 would normally have a check valve therein to prevent water from entering the air supply when the unit is shut off.

In mining operations, water pressure is usually about one hundred pounds per square inch and air pressure is in the neighbourhood of 60 to pounds per square inch. In the embodiment of the invention illustrated, the diameter of the elbow 12 and the flow path 14 is one-half inch.

The invention is capable of considerable variation. It has been illustrated with a piston that is responsive to the build up of hydraulic pressure, but it is within the contemplation of the inventor that a bleed-off of air on a controlled time basis could also operate a piston or the like to close off the flow of water. It is also contemplated that other triggering mechanisms for the piston might be used. Moreover, alternative means for positioning the piston prior to its actuation by the build up of pressure might be employed. The embodiment illustrated is thought to be very simple and useful, but the invention is not thought to be restricted to the embodiment illustrated.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. A device for spraying water with an automatic shut off comprising a body,

, a nozzle,

a first passage through said body terminating at said nozzle through which water can be sprayed,

a piston free for movement in said first passage between an open position which permits flow through said first passage and a closed position which stops flow through said first passage,

said piston having a front end and a back end, said front end being adapted to enter said first passage to stop flow therethrough when it assumes a closed position as aforesaid,

a pressure chamber in said body in fluid communication with the back end of said piston,

said piston being responsive to a predetermined build up of fluid pressure in said pressure chamber to move from said open position to said closed position,

means responsive to the flow of water through said first passage to build up said predetermined pressure in said pressure chamber over a predetermined period of flow time.

2. A device for spraying water with an automatic shut off as claimed in claim 1 in which said back end of said piston is of a larger area than said front end.

3. A device for spraying water with an automatic shut off as claimed in claim 1 in which the front end of said piston is partially in said first passage when said piston is in said open position.

4. A device for spraying water with an automatic shut off as claimed in claim I in which the front end of said piston is partially in said first passage when said piston is in said open position.

5. A device for spraying water with an automatic shut off as claimed in claim 1 in which said means is responsive to flow of water through said first passage to build up pressure in said pressure chamber including a passage in said body between said first passage and said chamber.

6. A device for spraying water with an automatic shut off as claimed in claim I having yieldable means for said closure means loaded to normally urge said closure means to said open position.

7. A device for spraying water with an automatic shut off as claimed in claim 1 in which the back end of said 6 sage when said piston is in said open position, said means responsive to flow of water through said first passage to build up pressure in said pressure chamber including a passage in said body between said first paspiston is in fluid communication with said chamber, the 5 sage and said chamber.

Claims

1. A device for spraying water with an automatic shut off comprising a body, a nozzle, a first passage through said body terminating at said nozzle through which water can be sprayed, a piston free for movement in said first passage between an open position which permits flow through said first passage and a closed position which stops flow through said first passage, said piston having a front end and a back end, said front end being adapted to enter said first passage to stop flow therethrough when it assumes a closed position as aforesaid, a pressure chamber in said body in fluid communication with the back end of said piston, said piston being responsive to a predetermined build up of fluid pressure in said pressure chamber to move from said open position to said closed position, means responsive to the flow of water through said first passage to build up said predetermined pressure in said pressure chamber over a predetermined period of flow time.

4. A device for spraying water with an automatic shut off as claimed in claim 1 in which the front end of said piston is partially in said first passage when said piston is in said open position.

6. A device for spraying water with an automatic shut off as claimed in claim 1 having yieldable means for said closure means loaded to normally urge said closure means to said open position.

7. A device for spraying water with an automatic shut off as claimed in claim 1 in which the back end of said piston is in fluid communication with said chamber, the front end of said piston being partially in said first passage when said piston is in said open position, said means responsive to flow of water through said first passage to build up pressure in said pressure chamber including a passage in said body between said first passage and said chamber.