US3827609A

US3827609A - Valve for liquid sprayer

Info

Publication number: US3827609A
Application number: US00371113A
Authority: US
Inventors: A Arnaldo
Original assignee: Individual
Current assignee: Individual
Priority date: 1973-06-18
Filing date: 1973-06-18
Publication date: 1974-08-06
Anticipated expiration: 1991-08-06

Abstract

The present invention relates to a valve for a pressurized fluid spraying container wherein the spraying container includes at the top thereof a small circular opening having a rim about the opening and a seal disposed inside the container against the rim. The valve comprises a housing open at the top and disposed inside the container with the upper edge pressing against the seal to make sure that the seal is tight between the rim and the housing. In addition, the valve comprises a plunger which is mounted to slide through the opening and the seal, with the lower part inside the housing. The plunger is formed at the lower part thereof with a resilient member of any shape which is unitary with the plunger and is adapted to enable the plunger to be just slightly depressed and to spring back to its original position when the plunger has ceased to be slightly depressed. The valve should of course be arranged for permitting the fluid spray to escape from the container as the plunger is being depressed.

Description

United States Patent [191 Arnaldo Aug. 6, 1974 1 VALVE FOR LIQUID SPRAYER [76] Inventor: Amabili Arnaldo, 2101 Champlain, Suite 416, Montreal 133, Province de Quebec, Canada 221 Filed: June 18, 1973 21 App1.No.:371,113

[52] US. Cl ZZZ/402.24, 251/321, 222/518, 222/512 [51] int. C1 365d 83/14 [58] Field of Search 222/402.24, 402.1402.13, 222/402.14402,19, 402.21, 512, 518; 251/337, 322; 267/182 Lehmann 222/402.13 X

Primary ExaminerRobert B. Reeves Assistant ExaminerH. Grant Skaggs Attorney, Agent, or Firm--Bacon & Thomas 1 1 ABSTRACT The present invention relates to a valve for a pressurized fluid spraying container wherein the spraying container includes at the top thereof a small circular opening having a rim about the opening and a seal disposed inside the container against the rim. The valve comprises a housing open at the top and disposed inside the container with the upper edge pressing against the seal to make sure that the seal is tight between the rim and the housing. In addition, the valve comprises a plunger which is mounted to slide through the opening and the seal, with the lower part inside the housing. The plunger is formed at the lower part thereof with a resilient member of any shape which is unitary with the plunger and is adapted to enable the plunger to be just slightly depressed and to spring back to its original position when the plunger has ceased to be slightly depressed. The valve should of course be arranged for permitting the fluid spray to escape from the container as the plunger is being depressed.

12 Claims, 11 Drawing Figures PAIENTEnAus sum SHEET 1 0F 2 VALVE FOR LIQUID SPRAYER This invention relates to a valve for liquid sprayer. More particularly, the present invention relates to a valve which is adapted to be mounted on a pressurized fluid spraying container.

Everyone is aware of the fact that the valve which is usually provided on the fluid spraying devices which are usually found on the market consists of four parts, namely a lower part which is connected to a plastic tube, the later extending to the bottom of the container, an upper part which is slidably received in the lower part, but which is retractable therefrom by means of a coil spring, and a rubber ring surmounting the upper part. The upper part is terminated by a short tubular portion over which the rubber ring is mounted. When pressing the push button of the fluid spraying container, this will depress the small tubular portion of the upper part and will unseal a small opening provided in the short tubular portion with the result that the fluid will flow from the lower part into the small opening through the short tubular portion after which it will exit in the form of a spray. The spring will thereafter cause the upper portion to be urged upwardly with the result that the small opening in the short tubular portion will again be sealed by the rubber ring.

The main disadvantage of this valve resides in the fact that it must be assembled from a plurality of parts including a small coil spring, thus requiring first the production of this coil spring and then the assembly of this coil spring with the various parts of the valve. This will appear to be a time consuming operation and in view of the fact that millions of pressurized fluid spraying containers are sold every day throughout the world, it will be realized that a substantial economy could be made by dispensing with the above mentioned coil spring and assembly of parts. In other words, it is felt that a breakthrough could be achieved by replacing the lower part, the upper part and the coil spring of the device actually found on the market by a single unitary article. Furthermore, it is obvious that a unit formed of many parts can more easily be damaged than a unit constructed with lesser parts.

The present invention relates to a valve for a pressurized fluid spraying container wherein the spraying container includes at the top thereof a small circular opening having a rim about the opening and a seal disposed inside the container against the rim. The valve comprises a housing opened at the top and disposed inside the container with the upper edge pressing against the seal to make sure that the seal is tight between the rim of the housing. In addition, the valve comprises a plunger which is mounted to slide through the opening and the seal with the lower part inside the housing. The plunger is formed at the lower part thereof with a resilient member of any shape which is unitary with the plunger and is adapted to enable the plunger to be just slightly depressed and to spring back to its original position when the plunger has ceased to be slightly depressed. The valve should of course be arranged for permitting the fluid spray to escape from the container as the plunger is being depressed.

In the drawings which illustrate the invention,

FIG. 1 is a perspective view illustrating the action of depressing the plunger to produce a fluid spray;

FIG. 2 is a cross-section view througha valve according to the invention;

FIG. 3 is an exploded perspective view of the valve illustrated in FIG. 2;

FIG. 4 is a cross-section view of the valve illustrated in FIG. 2, the valve being shown in position for producing a fluid spray;

FIG. 5 is a side view of the resilient ring shown in FIGS. 2, 3 and 4;

FIG. 6 is a cross-section view of an alternative form of resilient member;

FIGS. 7 and 8 are views of other forms of resilient member;

FIG. 9 is a cross-section view of a modified valve according to the invention;

FIG. 10 is a cross section view of still another embodiment according to the invention which illustrates a stopper for the valve;

FIG. 11 is a cross-section view of another embodiment.

Referring to the drawings, more particularly to FIGS. 1 to 5, the valve which is illustrated is intended to be mounted on a pressurized fluid spraying container 1 which is of standard construction and includes at its top a smaller circular opening having a rim 3 about the opening. Another item which is well known and which is standard in this kind of container is a ring type seal 5 which is disposed inside of the container against the rim 3 in the particular manner illustrated in the drawings. The valve itself is made of two parts: a housing 7 and a plunger 9. Referring to the drawings, it will be seen that the housing 7 has a circular cylindrical shape, or in other words 7 is a tubular housing of circular cross-section. Reference is particularly made to FIG. 3 of the drawings. The housing 7 is opened at its top and is disposed inside the container 1 with the upper edge 11 pressing against the rubber seal 5 so as to make sure that the seal is really tight between the rim 3 and the housing 7. Referring now to FIGS. 2, 3 and 4 it will be seen that the tubular housing 7 which has a circular cross-section has'its upper portion formed with four longitudinal channels 13 which are distributed around the inner surface in the upper portion of the housing 7. The purpose of these longitudinal channels will be explained in detail hereinafter.

The tubular housing 7 has an outward flange 14 along its upper edge 11. On the other hand, the rim 3 has an enlarged portion 15 inside of which the rubber seal 5 and the flange portion 14 of the tubular housing 7 will be received. In this manner, the tubular housing 7 will be inside the container 1 with its upper edge 11 pressing against the seal 5.

At the bottom 17 of the housing 7, there is a central opening 19 and a tube 21 which projects downwardly from the bottom 17 inside the container 1. Finally, the bottom 17 of the tubular housing 7 is provided with four channels 23 which extend radially from the opening 19 towards the periphery of the bottom 17.

It has been said above that the second main component of the valve illustrated is the plunger 9. The plunger 9 has the appearance of a rod which is shaped to be able to slide through the rim 3 and the ring type rubber seal 5. The portion of the plunger 9 which is inside the housing 7 is formed with a piston 25 which is circular and has a diameter which is substantially identical to the inner diameter of the tubular housing 7. As aforesaid, the piston is also circular and has a thickness which slightly, regularly and radially increases outwardly from the body of the plunger to the outer periphery of the piston thus defining a pointed upper edge 27 at the outer upper periphery which will be seen to be sealingly resting against the rubber seal 5 when the valve is in the position illustrated in FIG. 2 of the drawings, i.e. the rest position of the valve. Referring again to FIGS. 2 and 4 of the drawings, it will be seen that the portion of the plunger which is above the piston 25 has a bore 29 and a longitudinal slit 31 which extends from the piston 25 to a point 33 of the plunger where the plunger is in contact with the rubber seal 5.

The lower portion of the plunger 9 comprises a resilient ring 35 which is unitary with the plunger and wherein its plane is in the prolongation of the axis of the plunger 9. The resilient ring 35 will obviously have to be shaped to be insertable with play in the tubular housing, for example its diameter will be small enough to leave a space a between the walls of the tubular housing 7 and the resilient ring 35 when the valve is in the rest position illustrated in FIG. 2 of the drawings. In this manner, it will be possible to permit that the resilient ring 35 be flexed with depressing the plunger thus reducing space a to space a (FIG. 4). Bcause the resilient ring 35 is made of a resilient material such as plastics, the ring will cause the plunger to spring back to the rest position of the valve at the end of the period of depressing the plunger 9.

The operation of this valve will be quite simple. The outside appearance of the pressurized fluid spray container 1 provided with the valve according to this invention is exactly the same as the one which is commonly found on the market. For example, container 1 itself is exactly the same and the push button 37 is also the same. The net result will appear to be exactly the same to the general public. For example, when pressing down the push button 37, a spray 39 will be produced and it will last as long as the push button 37 is being pressed down. When the operator of the fluid spray container removes his finger 41 from the push button 37, the valve will revert back to its rest position and the spray 39 will stop. In other words, when pressing down the push button 37 in the direction of the arrows 43, the plunger 9 over which the push button 41 is mounted will descend a minute distance and will be moved from the position indicated in FIG. 2 to the one illustrate in FIG. 4 in the direction of the arrows 43. This will cause the portion of the ring type rubber seal 5 which immediately surrounds the plunger 5 to be slightly depressed while however remaining in contact with the plunger at the upper inner edge 49 thereof. This will appear to be essential in order to prevent any escape of fluid spray through the rim 3 of the container 1. As the plunger 9 is being depressed and the rubber seal 5 occupies the position which has just been described, the piston 25 will move down a certain distance b as illustrated in FIG. 4 with the result that the edge 27 of the piston 25 looses its contact with the rubber seal 25. The depressing action originally caused by the finger 41 and transmitted to the plunger 9 through the push button 37 will also cause the resilient ring 35 to be slightly deformed exactly in the manner illustrated in FIG. 4 of the drawings. It will be realized that the original shape of the ring 35 in the rest position of the valve will be the one illustrated in FIG. 2 and more particularly the shape indicated in dotted lines in FIG. 4. After the plunger has been depressed, the ring will be slightly crushed or deformed to adopt the shape indicated in full line in FIG. 4. Particularly, the ring 35 will have its upper arc deformed in the direction indicated byarrow c and its lateral arcs deformed along the lines indicated by each of the arrows d and 2. One will realize that once the resilient ring 35 has been deformed in the exact manner shown in FIG. 4 there will be established a continuous circuit for the escape of a fluid spray.

We will now describe this circuit. The fluid which is inside the container 1 under a pre-established pressure, which can for example be made possible by the presence of a pressurized gas such as Freon, the later being a trade mark for a group of halogenated hydrocarbons such as chlorodifluoromethane, can therefore exit from the container 1 by following the path established by the aforementioned circuit.

This path will be as follows. The fluid which is under pressure inside of the container will first exit through the bore 29 of the tube 21 in the direction indicated by the arrow 51. The fluid spray will thereafter hit the underface 53 of ring 35 (reference is particularly made to FIG. 5 of the drawings) but will be allowed to escape therefrom by circulating through the opening 19 and the various channels 23 which are formed at the bottom 17 of the housing 7 to thereafter ascend in the tubular housing 7 by following the paths defined by the various arrows f, g, h, and i. It will be realized that because the ring has the shape illustrated in FIG. 5 of the drawings, once the fluid under pressure has escaped from underneath the ring 35 by having by-passed the underface 53 it will be allowed to circulate upwardly and freely inside the tubular housing 7. Because the gas is under pressure in the housing 7, it will naturally has a tendency to escape by the next openings. These will be found in the various longitudinal channels 13 which are formed in the upper portion of the tubular housing 7, with the result that the fluid spray will further advance along its preestablished path following the arrows j and k again illustrated in FIG. 4 of the drawings.

The piston 25 having lost contact with the ring type rubber seal 5 at 27 the fluid spray will bypass the piston 5 in the exact direction indicated by arrow 1 where it will occupy the space 55 between the upper portion of the piston 25 and the ring type rubber seal 5. The fluid' spray which is still under pressure will then advanced through the slit 31, along arrow m, inside the bore 39 via nozzle 57 after which it will form the spray 39.

We have described the valve according to the invention in connection with a plunger 9 which is unitary with a resilient ring 35. It is obvious that any modification of the shape of the ring or any other resilient member which is unitary with the ring can serve the same purpose and are obviously within the scope and spirit of the present invention. For example, instead of providing the plunger 9 with a resilient ring 35 having the shape illustrated in FIG. 5 of the drawings, one can adopt any one of the devices illustrated in FIGS. 6, 7 and 8 of the drawings. In FIG. 6, the resilient action which is exerted on the plunger forcing it to revert back to a rest position at the end of the depressing action by finger 41 consists of a resilient band 59 which has the shape of a double V lying side ways in which the upper portion is connected to the piston 25 at 61 in the man-. ner illustrated in FIG. 6 of the drawings. The lower portion of the band 59 rests at the bottom 17 of the tubular housing 7 and circulation is again assured by the presence of the opening 19 and channels 23 in the bottom 17.

tary by being connected at the upper portion thereof at 67 and 69 to the piston 5 and by being joined to the bottom 17 by means of a connecting band 71. Again in this case, the circulation of the fluid spray will be assured by the presence of the opening 19 and channels 23 in the bottom 17 of the tubular housing 7.

Finally, the other possibility which is illustrated in the drawings, is the one which is shown in FIG. 8 of the drawings. The resilient member illustrated therein comprises a pair of resilient facing convex arms 73 and 75 wherein the convex portions of each arms are allowed to face one another in spaced relationship and wherein these arms are connected to the piston 5 respectively at 77 and 79. The lower tip of these arms 73 and 75 are just allowed to rest at the bottom 17 of the tubular housing. Again in this case, the circulation will be assured by the same path as defined above for the embodiment illustrated in FIGS. 2 to 4 of the drawings.

In another construction of pressurized fluid spraying container the valve is completely located inside the container and in this case, the plunger is in two sections, one consisting of a rod 9a which is solid with the piston and projects above the piston 25 a certain distance thereabove but remains inside the tubular housing without projecting through the ring 5 and rim 3 as in the case illustrated in FIGS. 2 to 4 of the drawings. The second portion of the plunger consists of a separate bored member 9b which is engaged at its lower end over the rod 9a. It will be seen that in this case, it is the bored member 9b which will be slidable through the rim 3 and the ring type seal 5. The slit 31 will be formed on the bored member 9b and will extend from the upper face of the piston 25 to a point 81 which is located between the underface of the ring type rubber seal 5 and the upper end of the rod 9a. In this case, the tubular housing 7 will not need the longitudinal channels 13 for permitting the circulation of the fluid spray around the piston 25 into the bore 29. The piston 25 however must be slightly modified and instead of having the shape illustrated in FIGS. 2 and 5, it will consists of the piston itself and a cylindrical portion 83 in which the upper edges 85 will abut the seal 5 in sealing engagement therewith in the exact manner illustrated in FIG. 9 of the drawings, it being obvious that this position of the valve is the one wherein the valve is in the rest position, that is when no spray 39 is being formed. It should also be noted that in this case the crosssection of the piston is smaller than the cross-section of the tubular housing. The operation is similar to the one of the valve illustrated in FIGS. 2 to 4 but the path is slightly modified by the fact that instead of going through the channels 13, the fluid merely escapes around the cylindrical portion 85 which is at all time spaced from the inner walls of the tubular housing 7. Once the plunger has been depressed, the upper edges 85 will be disengaged from the rubber seal 5 and the circulation will be the same as in the other valve.

Finally, it has been found quite desirable to stop the downward motion of the valve in order to preserve the resiliency in the resilient member such as the resilient ring 35. For this purpose, in accordance with an embodiment of the invention, there is provided a stopper. In this case, the tubular housing 7 has an upper portion 87 of larger cross-section than the lower portion 89 thereof. This will be seen to define a shoulder 91 between the upper portion 87 and the lower portion 89 of the tubular housing 7. All around the inner surface of the upper portion 87 of the tubular housing 7, there are formed a plurality of longitudinal ribs 93, preferably six in number such as illustrated in FIG. 10 of the drawings. In addition, the shoulder 91 is provided with projections 95 which are aligned with the longitudinal ribs 93. In this manner, when the plunger is depressed, the piston 25 will be spaced from the inner walls of the upper portion 87, the underface of the piston 25 will come the rest against the projections 95 and the liquid spray will be able to escape from the tubular housing in the spaces between the projections 95 and the ribs 93. Otherwise the operation of the valve is the same as in the case of the valve illustrated in FIGS. 2 to 4 of the drawings.

The material with which the valve and especially the resilient member such as the ring 35 is constructed causes no serious problem to the man of the art. It is merely necessary to make a selection of a material which will be slightly deformed and will spring back to its original position without substantial permanent deformation even after a large number of operations. Such material is easily available and the choice will depend on circumstances. Plastic will of course be preferred.

In the embodiment illustrated in FIG. 11, the tubular housing 7 has an upper portion 87 and a lower portion 89 of smaller cross-section than the upper portion to define a shoulder 91. The plunger consists of two parts, namely 9a and 9b, it being understood that the part 9b is bored at 29 to fit over part 9a all in the manner illustrated in FIG. 11 of the drawings. The piston 25 has an upper cylindrical portion 83 which is thick enough to be spaced from the part 9a of the plunger, just enough to tightly engage part 9b over part 9a. The upper edge of the cylindrical portion 83 will be formed towards the inner side thereof with an abutting ring designed to rest against the underside of the ring 5 in sealing engagement therewith when the valve is in the rest position. The outer peripheral surface of the cylindrical portion 83 including the piston 25 has a pair of oppositely situated

longitudinal channels

97, 99 to enable the fluid to escape from underneath the piston 25 when the valve is opened. To further enable said escape of fluid, the piston 25 and the cylindrical portion are just slightly spaced from the inner walls of the upper portion 87. The plunger is prevented from being too much depressed by the shoulder 91 which serves as a stopper when the valve is in operation.

The path of fluid in this valve will be as follows when the plunger 9a, 9b is depressed.

The fluid will escape through opening 19, channels 23, chamber 101 inside the tubular housing,

channels

97, 99 slit 31 and bore 29.

I claim:

1. A valve for a pressurized fluid spraying container, wherein said spraying container includes at the top thereof a small circular opening having a rim about the opening and a seal disposed inside said container against said rim, said valve comprising:

a housing open at the top and disposed inside said container with the upper edge pressing against the seal to enable said seal to be tight between said rim and said housing;

a plunger mounted to slide substantially vertically downwardly through the rim opening and said seal, with the lower part inside said housing and the upper part being of tubular form;

said plunger being formed at the lower part thereof with resilient means, which are integral with said plunger, in the form of a continuous loop of material engaging the bottom of said housing and adapted to flex downwardly to permit the plunger to be slightly resiliently depressed and to spring back to its original position after said plunger has been depressed and released; and

means integral with said plunger and engageable with said seal but movable away from said seal to permit an escape of fluid spray from said container through said tubular upper part when the plunger is depressed.

2. A valve according to claim 1, wherein said lastnamed means is a piston between said resilient means and said seal, said piston being movable inside said housing, and having a sealing edge in contact with said seal when said valve is in rest position to prevent any escape of fluid from said container when said valve is in said rest position.

3. A valve according to claim 2, wherein said-housing is tubular and has a substantially circular cross-section, said piston being also circular and having a thickness which slightly, regularly and radially increases outwardly from said plunger to the outer periphery of said piston, to define a pointed upper edge at said outer periphery, said pointed upper edge sealingly resting against said seal when said valve is in said rest position, said piston being downwardly and upwardly movable inside said tubular housing between said rest position and a depressed position.

4. A valve according to claim 3, wherein said piston has a diameter substantially equal to the inner diameter of said tubular housing, said tubular housing being formed with longitudinal channels in the upper portion of said housing around the inner surface thereof, said longitudinal channels enabling said fluid to escape from said tubular housing when said pointed upper edge of said piston is disengaged from said seal.

5. A valve according to claim 4, wherein said tubular housing has an outward flange along the upper edge thereof, said rim being formed with an enlarged portion to receive said flange and retain said tubular housing fixed inside said container with the upper edge pressed against the seal.

6. A valve according to claim 5, wherein said plunger has a slit above said piston communicating with the bore of said tubular portion and extending from said piston to a point of said plunger where said plunger is in contact with said seal, said slit permitting a fluid spray to enter said bore to exit from said valve.

7. A valve according to claim 1 including a tube at the bottom of said housing to define a central opening in said bottom, said tube projecting in said container, and radially formed channels extending from said central opening towards the periphery of said bottom, thus enabling said fluid to circulate successively through said tube, said central opening and said radially formed channels into said tubular housing.

8. A valve according to claim 7, wherein said resilient loop is a ring which has a widened area in the arc portion thereof which rests on said bottom so as to enable said ring to be centered inside said tubular housing.

9. A valve according to claim 6,.wherein said resilient loop includes a pair of V shaped resilient side bands lying side ways with the apex bottom of said VS spaced from and facing one another.

10. A valve according to claim 2, wherein said housing is tubular and has a substantially circular crosssection, said piston being also circular and having an area which is smaller than the cross-section of said tubular housing to be able to move downwardly and upwardly with play inside said housing, said piston being provided with a cylindrical portion at the upper edges thereof abutting said seal in sealing engagement therewith when said valve is in said rest position, said plunger being formed of a rod which is integral with the piston and projects thereabove and a separate bored member which is engaged at the lower end over said rod, said bored member being said tubular portion and slidable through said rim and said seal, a slit being longitudinally formed at the lower end of said bored member between said piston and said seal to permit an escape of said fluid from said housing.

11. A valve as defined in claim 3, wherein said tubular housing has an upper portion of larger internal cross-section than the lower portion thereof, to define a shoulder between said upper portion and said lower portion, longitudinal ribs formed around the peripheral surface of said upper portion, projections on said shoulder aligned with said longitudinal ribs, so constructed and arranged that when said plunger is depressed, the underface of said piston, comes to rest against said projections, and said liquid spray escapes from said tubular housing in the spaces between said projections and said ribs. 12. A valve according to claim 2, wherein said housing is tubular and has a substantially circular crosssection, said tubular housing having an upper portion of larger internal cross-section than the lower portion thereof to define a shoulder between said upper portion and said lower portion, said piston being also circular and having an area which is smaller than the crosssection of the upper portion of said tubular housing so as to clear the inner surface of said upper portion and to permit an escape of fluid between the outer edges of said piston and the inner surface of said upper portion, said plunger being a rod which is integral with the piston and projects thereabove, and a separate bored member which is engaged at the lower end over said rod, said bored member being said tubular portion and slidable through said rim and said seal, the upper edge of said piston defining a ring adapted to rest against the underside of said seal in sealing engagement therewith when the valve is in rest position, a slit being longitudinally formed at the lower end of said bored member said slit extending to a point of said bored member where said bored member is in contact with said seal, the outer peripheral surface of said piston being formed with a plurality of longitudinal channels to permit fluid under pressure to by-pass said piston and said cylindrical portion.

Claims

1. A valve for a pressurized fluid spraying container, wherein said spraying container includes at the top thereof a small circular opening having a rim about the opening and a seal disposed inside said container against said rim, said valve comprising: a housing open at the top and disposed inside said container with the upper edge pressing against the seal to enable said seal to be tight between said rim and said housing; a plunger mounted to slide substantially vertically downwardly through the rim opening and said seal, with the lower part inside said housing and the upper part being of tubular form; said plunger being formed at the lower part thereof with resilient means, which are integral with said plunger, in the form of a continuous loop of material engaging the bottom of said housing and adapted to flex downwardly to permit the plunger to be slightly resiliently depressed and to spring back to its original position after said plunger has been depressed and released; and means integral with said plunger and engageable with said seal but movable away from said seal to permit an escape of fluid spray from said contaiNer through said tubular upper part when the plunger is depressed.

2. A valve according to claim 1, wherein said last-named means is a piston between said resilient means and said seal, said piston being movable inside said housing, and having a sealing edge in contact with said seal when said valve is in rest position to prevent any escape of fluid from said container when said valve is in said rest position.

3. A valve according to claim 2, wherein said housing is tubular and has a substantially circular cross-section, said piston being also circular and having a thickness which slightly, regularly and radially increases outwardly from said plunger to the outer periphery of said piston, to define a pointed upper edge at said outer periphery, said pointed upper edge sealingly resting against said seal when said valve is in said rest position, said piston being downwardly and upwardly movable inside said tubular housing between said rest position and a depressed position.

9. A valve according to claim 6, wherein said resilient loop includes a pair of V shaped resilient side bands lying side ways with the apex bottom of said VS spaced from and facing one another.

10. A valve according to claim 2, wherein said housing is tubular and has a substantially circular cross-section, said piston being also circular and having an area which is smaller than the cross-section of said tubular housing to be able to move downwardly and upwardly with play inside said housing, said piston being provided with a cylindrical portion at the upper edges thereof abutting said seal in sealing engagement therewith when said valve is in said rest position, said plunger being formed of a rod which is integral with the piston and projects thereabove and a separate bored member which is engaged at the lower end over said rod, said bored member being said tubular portion and slidable through said rim and said seal, a slit being longitudinally formed at the lower end of said bored member between said piston and said seal to permit an escape of said fluid from said housing.

11. A valve as defined in claim 3, wherein said tubular housing has an upper portion of larger internal cross-section than the lower portion thereof, to define a shoulder between said upper portion and said lower portion, longitudinal ribs formed around the peripHeral surface of said upper portion, projections on said shoulder aligned with said longitudinal ribs, so constructed and arranged that when said plunger is depressed, the underface of said piston, comes to rest against said projections, and said liquid spray escapes from said tubular housing in the spaces between said projections and said ribs.

12. A valve according to claim 2, wherein said housing is tubular and has a substantially circular cross-section, said tubular housing having an upper portion of larger internal cross-section than the lower portion thereof to define a shoulder between said upper portion and said lower portion, said piston being also circular and having an area which is smaller than the cross-section of the upper portion of said tubular housing so as to clear the inner surface of said upper portion and to permit an escape of fluid between the outer edges of said piston and the inner surface of said upper portion, said plunger being a rod which is integral with the piston and projects thereabove, and a separate bored member which is engaged at the lower end over said rod, said bored member being said tubular portion and slidable through said rim and said seal, the upper edge of said piston defining a ring adapted to rest against the underside of said seal in sealing engagement therewith when the valve is in rest position, a slit being longitudinally formed at the lower end of said bored member said slit extending to a point of said bored member where said bored member is in contact with said seal, the outer peripheral surface of said piston being formed with a plurality of longitudinal channels to permit fluid under pressure to by-pass said piston and said cylindrical portion.