Liquid Spraying Device

Abstract

A refillable hand-operated liquid sprayer of the type which requires no container pressurizing gas nor other foreign propellant. It operates to pump a small quantity of liquid to be sprayed from a container to a small cylindrical chamber wherein the liquid is pressurized by the force of a coiled spring which is stressed during "cocking" stroke preparatory to spraying the liquid from the device. A cover unit is removably mounted on the open end of the container, and a spray head is rotatably mounted on the cover unit, the rotation of the head relative to the unit causing the spring to be compressed and simultaneously sucking liquid up from the container into the chamber. A valve mechanism is provided for cutting off the spray by letting the pressure out of the cylindrical chamber or by blocking the communication between the chamber and a discharge valve immediately before the pressurized quantity of liquid is exhausted. With this arrangement, a high quality, very fine mist is maintained during spraying as well as a sharp cut-off of the spray is effected.

Description

This invention relates to liquid spraying devices and more particularly to an improved spraying device of the type which produces spray mist similar to that produced by the common aerosol bomb and which requires no container pressuring gas nor other foreign propellant.

Heretofore, various liquid spraying devices have been devised which are hand operated, and which can spray in mist form the many liquds commonly used today such as hair sprays, perfumes, toilet waters, deodorants and insecticides. Typical of such devices is one which operates to pump a small quantity of liquid to be sprayed from a container to a cylindrical chamber wherein the liquid is pressurized by the force of a spring which is stressed during "cocking" stroke preparatory to spraying the liquid from the device.

In devices of this type, a spray head rotatably mounted on the container functions to set the device in "cocked" position, and on being manually rotated relative to the container, causes a liquid pressurizing piston to move within the cylindrical chamber in a direction to increase the volume of the chamber thereby sucking liquid up thereinto. During this piston movement, the spring is progressively compressed so that, in the "cocked" position, it acts to urge the piston in the opposite direction to pressurize the liquid drawn into the chamber. To operate the spray device, it is necessary to actuate a push button discharge valve by a finger. Upon actuation, the piston starts its downward movement under the action of the compressed spring, producing a high quality spray mist. However, after the piston reaches its lowermost position, the pressure in the chamber decreases as a result of spraying, and accordingly, the quality, i.e., fineness of the spray mist is deteriorated. And, finally, the liquid emitting from the nozzle is changed into non-mist form. Thus, no sharp cut-off of the spray is obtained, resulting in liquid flowing out of the nozzle even after the termination of the spraying. The liquid thus flowing out tends to spread over the periphery of the push button and, in case of viscous liquid, clog the nozzle.

According to one embodiment of the present invention, there is provided an improved liquid spraying device including a valve mechanism which operates to let the pressure out of the liquid pressurizing chamber so as to cause a rapid decrease of the pressure before the pressure in the chamber drops below the minimum value producing spray mist, just prior to the piston reaching its lowermost position, thereby preventing liquid from flowing out of the nozzle in non-mist form.

According to another embodiment of the present invention there is provided an improved liquid spraying device including a valve mechanism which operates to block the communication between the liquid pressurizing chamber and the discharge valve before the pressure in the chamber decreases below the minimum value producing spray mist, just prior to the piston reaching its lowermost position, thereby preventing liquid from flowing out of the nozzle in non-sprayed form.

Therefore, it is an object of the present invention to provide a new and improved liquid spraying device capable of maintaining a high quality spray mist during spraying.

It is another object of the present invention to provide a liquid spraying device including a valve mechanism that operates to effect a sharp cut off of the spray.

It is a further object of the present invention to provide a valve mechanism for cutting off the spray in a manner to let the pressure out of a liquid pressurizing chamber.

It is still further object of the present invention to provide a valve mechanism for cutting off the spray in a manner to block communication between a liquid pressurizing chamber and a discharge valve.

These and other objects will be apparent from the following discription of the invention when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a vertical section of a first embodiment of a liquid spraying device constructed in accordance with the present invention;

FIG. 2 is a horizontal section taken on the line II--II of FIG. 1;

FIG. 3 is a perspective view of a cover unit and a cap ring to be mounted over the unit;

FIG. 4 is a perspective view of a slide member and a rotary cylindrical member to be received in the slide member;

FIG. 5 is a fragmentary, enlarged vertical section of FIG. 1, with a valve mechanism being closed;

FIG. 6 is a vertical section of a second embodiment of the present invention;

FIG. 7 is a perspective view of a valve member employed in the FIG. 6 embodiment;

FIG. 8 is a view similar to FIG. 7 illustrating a modified valve member;

FIG. 9 is a view similar to FIG. 5 but illustrating a third embodiment of the present invention;

FIG. 10 is an illustration of a fourth embodiment of the present invention;

FIG. 11 is a prespective view of a modified valve member;

FIG. 12 is an illustration of a fifth embodiment of the present invention;

FIG. 13 is an illustration of a sixth embodiment of the present invention;

FIG. 14 is a fragmentary, enlarged view of FIG. 13, with a valve mechanism being opened;

FIG. 15 is an illustration of a seventh embodiment of the present invention;

FIG. 16 is an illustration of an eighth embodiment of the present invention;

FIG. 17 is an illustration of a ninth embodiment of the present invention; and

FIG. 18 is an illustration of a tenth embodiment of the present invention.

Referring in more detail to the accompanying drawings, FIGS. 1 to 5 illustrate a first emobidment of the liquid spraying device 10 of the present invention which is dimensioned to be conveniently held in a hand.

Briefly, the spray device 10 comprises a cylindrical container 11 for storing a quantity of liquid to be sprayed, a cover unit 12 removably mounted on the container, and a spray head 13 rotatably mounted on the cover unit 12. When the head 13 is rotated relative to the container so as to "cock" the device, it operates to pump a small quantity of the liquid from the container to a small chamber 14 wherein the liquid is pressurized by the force of a spring which is stressed during the cocking stroke. The head 13 also includes a discharge nozzle communicating with the chamber 14 via a discharge valve which is operated by pushing a button at the top of the head to release the spray as required. A valve mechanism of special construction is provided for cutting off the spray in a manner to let the liquid pressure out of the chamber 14 immediately before the pressurized quantity of liquid is exhausted. The device may be "cocked" again to ready the same for further spraying.

As best seen in FIG. 1, the container 11 comprises a cylindrical receptacle 20 having an open upper end with internal threads 24 formed therein. The cover unit 12 includes an upwardly extending cylindrical guide 28 which is externally threaded around its lower periphery (see also FIG. 3) to screw into the threads 24 of the receptacle 20 to thereby close the upper end of the container against escape of liquid therefrom. The guide 28 is grooved below the threaded portion to provide a seat for an O-ring seal 29. The cover unit 12 also includes a cylinder 30 which is closed at its lower end by a wall 32. An inlet tube 36 extends downwardly from the wall 32 to a position closely adjacent the bottom of the recetacle 20.

A check valve 40 of conventional construction is mounted in the cylinder 30 and, in the illustrated embodiment, comprises a valve member 42 formed with an incomplete annular opening 43 and a pressure ring 44 for holding the valve member in place on the bottom surface of the cylinder. The liquid pressurizing chamber 14 is formed in the cylinder 30 axially between the check valve 40 and a piston ring 52.

The piston ring 52 is usually formed of suitable elastic material such as rubber, plastic material or leather and is slidably mounted in the cylinder 30 for reciprocating movement therein. The piston ring is fixedly mounted at the lower end of a piston 57 which extends downwardly from a slide member 58. It should be noted that the piston ring may be formed integral with the piston. An O-ring seal 59 is provided between the cylinder 30 and the piston 57 to prevent the liquid from flowing into a space defined between the cover unit 12 and the spray head 13.

The piston ring 52 also includes a central opening 60 which is adapted to slidably receive the lower portion of a hollow stem 62 in liquid-tight manner when the piston 57 moves upwardly from the position of FIG. 1 towards the cocked position. The hollow stem 62 is fixed with respect to the spray head 13 and is formed of a material that is sufficiently rigid not to cause the stem to bend when subjected to a considerable force acting axially thereon. The function of the hollow stem 62 is not only to serve as a guide for the vertically moving piston ring 52, but also to communicate the liquid pressurizing chamber 14 with a discharge valve 63. Another O-ring seal 64 is provided between the piston 57 and the hollow stem 62 for the same purpose as the O-ring seal 59.

The spray head 13 is adapted to telescope onto the cylindrical guide 28 exteriorly thereof to insure that its rotational movement relative to the guide is free sliding and non-binding. The lower end of the spray head 28 is grooved as at 72 to receive a flange 74 provided around the cylindrical guide 28. Thus, the spray head is prevented from vertical movement relative to the cylindrical guide once they are assembled to the position of FIG. 1.

The spray head 13 includes a top wall 78 having an integral coupling member 80 which is splined to the upper end of a rotary cylindrical member 84. Preferably, the spray head 13 and the rotary cylindrical member 84 may be moulded integrally.

The rotary cylindrical member 84 is provided with a flange 88 which is adapted to abut the underside of the top wall of a cap ring 85, when the rotary cylindrical member is mounted within the cylindrical guide, so as not to cause a compression coil spring 87 to move the cylindrical member 84 upwardly. The cap ring 85 is threadly mounted on the upper end of the cylindrical guide 28. As best seen in FIG. 4, the rotary cylindrical member 84 is in turn splined to the slide member 58.

As seen in FIGS. 1 to 4, the cylindrical guide 28 has formed internally thereof a pair of diametrically opposite, axial grooves 100, each of which is adapted to receive a ball 102 to cooperate with a substantially sinuous groove 104 formed in the outer periphery of the slide member 58, whereby the rotational motion of the spray head is converted into the vertical upward movement of the slide member. The sinuous groove 104 comprises a pair of diametrically opposite, axial sections 106 which are connected by two sections 108 each intersecting one axial section at its upper end and the other at its lower end. When the spray head 13 is rotated relative to the container 11 in a clockwise direction as viewed from above in FIG. 1, the rotational motion of the head is transmitted through the rotary cylindrical member 84 to the slide member 58, causing it to move upward against the action of the compression spring 87.

The spray head 13 is shaped at its top to fixedly receive a commercial discharge valve of the type commonly used in aerosol spray bombs. As seen in FIG. 1, the valve assembly 63 is a known type of push button discharge valve and comprises a casing 122 having a bore 124 and a cover member 126 for holding the casing 122 in place on the top wall of the spray head 13 with a gasket 136 interposed between the casing and the cover member. The gasket 136 is centrally apertured to receive a hollow valve stem 140 with a liquid-tight fit therein. The hollow valve stem 140 is closed at its lower end by an enlargement 142 which is adapted to receive the upper end of a spring 144. The hollow valve stem 140 also has a side port 146 extending through its side wall, the port being normally closed by the inner face of the hole 138 in the gasket 136. The valve casing 122 also includes a female coupling 147 depending therefrom which is adapted to fixedly receive the upper end of the hollow stem 62.

A trigger push button 150 is secured to the upper end of the valve stem 140. The button 150 has a conventional discharge nozzle 156 communicating with the interior of the hollow valve stem 140.

An air inlet valve 158 is provided on the horizontal portion of the cover unit 12, which extends downwardly into the receptacle 20 and is adapted to introduce air thereinto to thereby prevent occurrence of a negative pressure within the receptacle.

Preferably the above described structure of the spray device 10 is made substantially entirely of suitable plastic material, but the hollow stem 60 is formed of rigid material such as metal or hard plastic.

To operate the spray device 10, the container 11 may be grasped in one hand and simultaneously the spray head 13 is rotated relative to the container by the other hand in a clockwise direction as viewed from above in FIG 1. This will rotate the rotary cylindrical member 84 and accordingly the slide member 58 in the same direction, causing an upward movement of the slide member within the cylindrical guide 28. As a result, the lower end of the hollow stem 62 is received in the opening 60 of the upwardly moving piston ring 52, as seen in FIG. 5. During this upward movement of the slide member 58, the coil spring is progressively compressed and simultaneously the chamber 14 increases its volume, creating a negative pressure in the chamber. This pressure acts to open the check valve 40 so that the liquid under atmospheric pressure in the receptacle 20 is forced upwardly through the inlet tube 36 and check valve 40 into the chamber 14. When the slide member 58 is moved to its uppermost position, the axial grooves 106 of the slide member are brought into registry with the axial grooves 100 of the cylindrical guide 28, so that the force of the fully compressed spring 87 acts downwardly on the slide member 58, thereby tending to move the same downwardly. The spring force thus presurizes the liquid which is trapped in the chamber 14 between the closed check valve 40 and the piston ring 52. When, in this condition, the push button 150 is depressed, the discharge valve 63 is opened to release pressurized liquid from the liquid pressurizing chamber 14 through the hollow stem 62, bore 124 of the valve casing 122, a passage 170 of the valve stem 140 and nozzle 156. The pressure exerted on the liquid in the chamber 14 by the spring 87 is sufficient to generate a high quality, very fine mist spray comparable to that produced by conventional aerosol bombs. During spraying, the slide member 58 is progressively moved downwardly by the action of the spring 87.

According to one feature of the present invention, there is provided a valve mechanism for cutting off the spray by letting the pressure out of the chamber 14 immediately before the pressurized quantity of liquid is exhausted.

As best seen in FIG. 1, the hollow stem 62 is of such length as to terminate at a position immediately above the piston ring 52 when it is held in its lowermost position as shown. Thus, the piston ring 52 leaves the lower end of the hollow stem 62 immediately before the piston ring reaches the lowermost position. The piston 57 has a side opening 162 (see FIG. 4 also) for communicating the interior thereof with the space defined between the piston and the cylinder 30. The cylinder 30 also has a side opening 164 which opens to the interior of the receptacle 20. Thus, it will be understood that the valve mechanism is provided by the piston ring 52, the lower portion of the hollow stem 62 and the two openings 162 and 164.

While the valve mechanism remains closed, i.e., the piston ring 52 is received on the hollow stem 62 as shown in FIG. 5, the chamber 14 is communicated with only the discharge valve 63 through the hollow stem, so that the pressure in the chamber is transmitted to the discharge valve. However, when the valve mechanism is opened, i.e., the piston ring leaves the hollow stem, the chamber 14 is communicated with the interior of the receptacle 20 through the opening 60 and the two side openings 162 and 164. Thus, the pressure in the chamber 14 decreases rapidly to atmospheric pressure and accordingly to spray device 10 ceases to discharge the pressurized liquid from the nozzle 156.

With this arrangement, a high quality very fine mist is maintained during spraying. Further, it is possible to effect a sharp cut off of the spray without causing the liquid to emit from the nozzle in non-mist form.

In FIGS. 6 and 7, there is illustrated a second embodiment of the present invention in which a flexible tube 170 is employed to communicate the liquid pressurizing chamber 14 with the discharge valve 63. As shown, the upper end of the flexible tube is fixedly received in a coupling member 172 of the discharge valve 63 and the lower end thereof is fixedly received in a bore 174 formed in the piston 57. The piston 57 also has an axial bore 176 communicating with the bore 174, which opens to an enlarged end bore 178. The piston ring 52 mounted around the lower periphery of the piston 57 is of a conventional O-ring type.

Provided on the bottom of the cylinder 30 is a valve 180 which serves as the check valve 40 as well as the valve mechanism of the FIG. 1 embodiment. The valve 180 includes a body 182 which is held in place on the bottom surface of the cylinder 30 by suitable means (not shown). The body 182 has a central bore 186 extending therethrough and a side port 188 communicating with the bore 186. An inlet tube 36 is fixedly received in the lower portion of the bore 186, the lower end of the tube being disposed closely adjacent the bottom surface of the receptacle 20.

A generally cylindrical valve member 190 is mounted on the valve body 182 in the manner as shown in FIG. 6. As best seen in FIG. 7, the valve member 190 has an annular opening 192 formed in the upper end wall thereof, which is not quite complete with a break being provided so that the inner circular portion 194 is elastically connected to the remaining portion of the valve member to serve as a check valve. The valve member 190 also includes a projection 196 which extends radially outwardly from its upper peripheral portion and adapted to be engaged by the lower end of the piston 57. When the piston 57 moves downwardly, it engages the projection 196 and "peels" or forces the cylindrical wall 198 outwardly, bringing the side port 188 into communication with the interior of the cylinder 30. Thus, it will be appreciated that immediately before the pressurized quantity of liquid is exhausted, the liquid pressurizing chamber 14 is communicated with the receptacle 20 through the side port 188, bore 186 and inlet tube 36, causing a rapid reduction of the pressure in the chamber 14. Accordingly, the spray device ceases to produce spray mist.

FIG. 8 shows a modification of the valve member 190 employed in the FIG. 6 embodiment. As seen, the valve member 190' is different from that shown in FIG. 7 in that there is no inner circular portion corresponding to that indicated at 194 in FIG. 7. In this embodiment, however, the central bore 186 of the valve body 182 is closed at its top. During the cocking stroke, the cylindrical wall 198 is forced outwardly due to the pressure difference between the chamber 14 and the receptacle 20, so that the liquid is sucked up through the side port 188. When, on the other hand, the piston 57 moves downwardly, it engages the projection 196' and forces the cylindrical wall 198' outwardly, so that the pressurized liquid escapes from the chamber 14 into the receptacle 20 through the inlet tube 36.

In FIG. 9, there is illustrated a third embodiment of the present invention in which a cup-shaped valve member 204 is held in place on the bottom of the cylinder 30. As seen, the valve member 204 includes a bottom wall 206 which is formed with an incomplete annular opening 208 to provide a check valve. The cylinder 30 has a plurality of side openings 210 which are normally closed by the peripheral surface of the valve member 204. The valve member 204 is also tapered at its upper outer periphery 212 for the purpose to be described below.

The piston 57 has an end bore 214 which is tapered upwardly to slidably receive the tapered peripheral end 212 of the valve member 204. A plurality of grooves 216 are formed in the wall of the end bore 214 to communicate the interior of the valve member 204 with the exterior thereof when the tapered peripheral end 212 is brought into surface contact with the wall of the end bore 214.

When the piston 57 moves downwardly, it engages the tapered peripheral end 212 of the valve member 204 and then forces the peripheral wall thereof inwardly, opening the side openings 210. Thus, the interior of the valve member 204 is communicated with the receptacle 20 through the grooves 216 and side openings 210, so that the pressurized liquid is discharged into the receptacle.

In FIG. 10, there is shown a fourth embodiment of the present invention which is identical to that of FIG. 1 in that the pressurized liquid in the chamber 14 is discharged into the receptacle 20 through two side openings 152 and 164 formed in the piston 57 and the cylinder 30, respectively.

As seen, the piston 57 has an end bore 214 of considerable axial length in which a valve member 220 is slidably mounted. The valve member is biased downwardly by a compression spring 222. The piston 57 also includes an inwqrdly extedning flange 224 serving as a seat for the valve member 222. The valve member 222 has a central opening 226 which communicates with a plurality of radially extending grooves 228 formed in the lower surface thereof. The side opening 162 of the piston 57 is so positioned as to be closed by the side wall of the valve member 222 when the valve member is held in the position shown. The piston 57 is also grooved at its lower and upper periphery to provide seats for two O-ring seals 230 and 232, respectively.

A check valve 40 is provided on the bottom of the cylinder 30 and includes an upwardly extending projection 234 which is formed integral with the innew circular valve portion 194 of the valve 40.

During the cocking stroke, the check valve 40 remains open so that the liquid is sucked up into the liquid pressurizing chamber 14 through the inlet tube 36. When, during spraying, the piston 57 moves downwardly under the action of the spring 87, the valve member 220 engages the top surface of the projection 234 and then is moved upwardly relative to the piston 57 against the action of the spring 222. This will open the side opening 162, so that the cylinder 30 is communicated with the receptacle 20 through the side openings 162 and 164. A passage 130 of the flexible tube 170 is also communicated with the receptacle 20 through the central opening 226 and the radial grooves 228. Thus, it will be appreciated that with the arrangement of FIG. 10 it is possible to cut off the spray by letting the pressure out of the chamber 14 immediately before the pressurized quantity of liquid is exhausted.

FIG. 11 shows a modification of the valve member 220 of FIG. 10. The valve member 220' includes a greater-diameter portion 220a' which is adapted to be slidably received in the end bore 214. The valve member 220' also includes a small-diameter portion 220b' and is formed with a central bore 226' which communicates with a plurality of radially extending grooves 228' formed at the lower end of the valve member. In this embodiment, it is not necessary to provide the check valve 40 with the upwardly extending projection 234, as is the case with the FIG. 10 embodiment.

In FIG. 12, there is shown a fifth embodiment of the present invention which is identical to that of FIG. 9 in that the spray is cut off by letting the pressure out of the chamber 14 into the receptacle 20 through side openings 210 of the cylinder 30.

Provided on the bottom of the cylinder 30 is a check valve 40 of the same construction as that of FIG. 1, on which is mounted a cylindrical spring guide 240 having a lower peripheral flange 240a and an upper peripheral flange 240b. The lower peripheral flange 240a is of a diameter slightly larger than the inner diameter of the cylinder 30, so that the guide 240 may be received in the cylinder with a friction fit therein. On the other hand, the upper peripheral flange 240b is of a diameter somewhat smaller than the inner diameter of the cylinder, so that a valve member 242 is free to move axially between the cylinder wall and the peripheral surface of the upper flange 240b. As seen, the valve member 242 includes a radially inwardly extending flange 242a which is normally urged against the undersurface of the upper flange 240b by the action of a spring 244 received on the cylindrical guide 240. In the position shown, the valve member 242 closes the side openings 210 of the cylinder, blocking the communication between the cylinder and receptacle 20.

The piston 57 has a piston ring 52 attached thereto, which is adapted to be slidably received in the cylinder 30 in liquid-tight manner. The piston ring 52 includes a plurality of legs 52a extending downwardly therefrom, between which are formed passages 246 for communicating the inner cylindrical space of the piston ring 52 with an annular space 248 defined between the legs 52a and the inner wall of the cylinder.

As will be understood, when the piston 57 moves downwardly under the action of the spring 87, the legs 52a engage the valve member 242, causing it to move downwardly against the action of the spring 244. This downward movement of the valve member 242 opens the side openings 210 and accordingly communicates the interior of the cylinder 30 with the receptacle 20 through the passages 246 and the side openings 210. It should be noted that the side openings 210 are so positioned as to be opened by the valve member 242 immediately before the pressurized quantity of liquid is exhausted.

In FIGS. 13 and 14, there is illustrated a sixth embodiment of the present invention which is characterized in that the spray is cut off by blocking the communication between the liquid pressurizing chamber 14 and the discharged valve 63 immediately before the pressurized quantity of liquid is exhausted.

As seen, the hollow stem 62, which is formed of suitable rigid material such as metal and hard plastic, is fixed with respect to the spray head 13, as in the embodiment of FIG. 1. However, the lower end of the hollow stem 62 is closed and is provided with one or more side ports 250 instead.

During the cocking stroke, the piston ring 52 moves upwardly from the position of FIG. 13, so that the interior of the hollow stem 62 is communicated with the liqud pressurizing chamber 14 through the side ports 250, as is seen in FIG. 14. This upward movement of the piston ring 52 acts to open the check valve 40 and suck liquid up into the chamber 14 through the inlet tube 36 and the opened check valve.

With the spraying device 10 "cocked," if the push button 150 is actuated, the device emits the pressurized fluid in mist form from the nozzle 156, and the piston ring 52 is progressively moved downwardly under the action of the spring 87. However, immediately before the pressurized quantity of liquid is exhausted, the piston ring 52 reaches the position in which it closes the side ports 250, thereby blocking the communication between the liquid pressurizing chamber 14 and the discharge valve. Thus, the spraying device 10 ceases to emit liquid from the nozzle 156.

In FIG. 15, there is illustrated a seventh embodiment of the present invention which operates on the same principle as the FIG. 13 embodiment to cut off the spray immediately before the pressurized quantity of liquid is exhausted.

In this embodiment, however, a flexible tube 170 is employed to communicate the liquid pressurizing chamber 14 with the discharge valve 63. The piston 57 has an end before 178 converging upwardly to provide a valve seat 179.

A valve member 154 stands on the check valve 140 in upright manner, and comprises a base 254a, a stem 254b and a valve head 254c. The valve head is formed in the shape of an umbrella. The valve member 254 is formed of suitable elastic material such as rubber and soft plastic so that the valve head 254c is received on the valve seat 179 in liquid-tight manner. The valve member 254 is free to move upwardly from the position shown in FIG. 15 until the base 254a is restricted by a cup-shaped member 256. The cup-shaped member has an opening 258 formed in the bottom thereof that is greater in diameter than the stem 254b of the valve member 254.

During the cocking stroke, the piston 57 moves upwardly to open the check valve 40. It should be noted, in this connection, that since the valve member 254 is free to move upwardly, it does not hinder the check valve 40 from moving to its open position.

During the spraying, when the piston 57 moves downwardly and approaches its lowermost position, the valve head 254c is attracted to the valve seat 179 of the piston due to the action of the liquid flowing at high speeds through an upwardly converging space defined between the valve head 254c and the valve seat 179. This will move the valve member 254 upwardly so that the valve head 254c is received on the valve seat 179 in liquid-tight manner. Thus, the spraying device ceases to produce spray mist.

In FIG. 16, there is illustrated an eighth embodiment of the present invention which is imilar to those of FIGS. 13 and 15 in that the spray is cut off by blocking the communication between the liquid pressurizing chamber 14 and the discharge valve 63 immediately before the pressurized quantity of liquid is exhausted.

In this embodiment, the piston 57 has a piston ring 52 mounted thereon and is formed with an end bore 178 which converges upwardly to provide a valve seat 179.

A support member 260 is fixedly mounted on the check valve 40 at the bottom of the cylinder 30 and has a central opening 262 formed therein. The support member includes a downwardly extending leg portion 260a which is of such length that the opening movement of the check valve 40 is not prevented by the support member 260. The support member also includes an upwardly extending cylindrical portion 260b in which the lower end of a coil spring 264 is received. The upper end of the spring 264 is connected to a generally conical valve member 254.

As will be understood, when the piston 57 moves downwardly and approaches its lowermost position, the pressurized liquid flowing at high speeds through an annular space defined between the conical surface 254a of the valve member 254 and the valve seat 179 acts to cause the valve member to be attracted to the valve seat, thereby blocking the communication between the liquid pressurizing chamber 14 and the discharge valve 63.

In FIG. 17, there is illustrated a ninth embodiment of the present invention in which a ball valve 270 is provided in the piston 57 for blocking the communication between the liquid pressurizing chamber 14 and the discharge valve (not shown).

As seen, the piston 57 has an end bore 178 in which a coil spring 272 is received to urge a ball 274 against a valve seat 276 provided by a ring-like member 278. The strength of the coil spring 272 is so adjusted that the ball valve 270 remains open while the pressure in the chamber 14 is above a certain predetermined level which is slightly higher than the minimum pressure producing spray mist. Thus, when the piston 57 approaches its lowermost position and then the pressure in the chamber 14 drops below the predetermined level, the ball valve 270 is closed, blocking the communication between the chamber 14 and the discharge valve.

In FIG. 18, there is illustrated a tenth embodiment of the present invention which is smilar to those of FIGS. 13, 15, 16 and 17 in the provision of a valve mechanism for blocking the communication between the liquid pressurizing chamber 14 and the discharge valve (not shown).

In this embodiment, the valve mechanism is provided by the lower end of the piston 57 and the upper surface of the check valve 40. As seen, the piston 57 is tapered at its lower end to provide small annular room for the pressurized liquid between the piston, cylinder and check valve, when the piston is moved to its lowermost position where the lower end thereof is in fluid-tight contact with the upper surface of the check valve. Thus, it will be appreciated that the discharge valve is isolated from the liquid pressurizing chamber 14 to cut off the spray immediately before the pressurized quantity of liquid is exhausted.

From the foregoing description, it will now be apparent that the present invention provides an improved liquid spraying device which offers many advantages over the prior art devices. For example, the sprayer is completely safe whether or not in the cocked position, and requires no external power source to produce the spray mist. Since the container is not pressurized but rather serves as a convenient reservoir for the liquid to be sprayed, it is not subject to the explosion hazards of the common aerosol spray bombs.

In addition, it should be noted that with the provision of a novel valve mechanism that operates to let the pressure out of the liquid pressurizing chamber before the pressure within the same drops below the minimum valve producing spray mist just prior to the piston reaching its lowermost position, it is possible to effect a sharp cut-off of the spray at the termination of the spraying as well as to maintain an extremely high quality spray mist during the spraying, thereby enabling a desired liquid to be sprayed evenly over a surface of an object.

In another embodiment of the present invention also, it is understood that since the valve mechanism provided therein operates to block the communication between the liquid pressurizing chamber and the discharge valve immediately before the piston reaches its lowermost position, so as to produce a spray discharge only while the pressure in the chamber remains above the minimum value producing spray mist, an extremely high quality, very fine mist is maintained during the spraying as well as a sharp cut-off of the spray is accomplished thereby offering many other attendant advantages as described above.

Claims

What is claimed is:

1. A liquid spraying device comprising container means including a receptacle for holding a quantity of liquid and having an opening for filling the receptacle with the liquid, cover means removably mounted on the receptacle to close the opening and including an upwardly extending cylindrical guide, spray head means rotatably mounted on the cover means, slide means movably mounted within the cylindrical guide and operably connected to the spray head means whereby rotation of the spray head means relative to the cover means in a fixed direction moves the slide means upwardly, liquid pressurizing pump means including a cylinder and a piston defining a liquid pressurizing chamber, the cylinder being operably connected in fixed relation to the cover means and the piston being operably connected in fixed relation to the slide means, a spring mounted in the spray head means for biasing the slide means in a direction to decrease the volume of the liquid pressurizing chamber to thereby pressurize liquid therein, an inlet conduit for conducting the liquid in the receptacle to the chamber, an inlet check valve in the conduit, a discharge valve in the spray head means for controlling discharge of pressurized liquid from the chamber in the form of a spray, passage means for communicating the liquid pressurizing chamber with the discharge valve, and a valve mechanism for cutting off the spray immediately before the pressurized quantity of liquid is exhausted.

2. A liquid spraying device according to claim 1, in which the valve mechanism operates to cut off the spray by letting the pressure out of the liquid pressurizing chamber immediately before the pressurized quantity of liquid is exhausted.

3. A liquid spraying device according to claim 1, in which the valve mechanism operates to cut off the spray by blocking the communication between the liquid pressurizing chamber and the discharge valve immediately before the pressurized quantity of liquid is exhausted.

4. A liquid spraying device comprising a container having a reservoir for holding a quantity of liquid and an opening for filling the same with liquid, a cover unit adapted to close the opening and including a cylinder extending downwardly into the container, the cover unit also including a cylindrical guide extending upwardly therefrom and having a pair of diametrically opposite axial grooves formed internally thereof, a spray head rotatably mounted on the cylindrical guide, a slide member mounted in the cylindrical guide for vertical movement therein and including a piston slidably received in the cylinder, the piston and cylinder defining a liquid pressurizing chamber therebetween, the slide member having a sinuous groove formed externally thereof which comprises a pair of diametrically opposite axial sections and a pair of intersecting sections each intersecting at one end the upper end of one axial section and at the other end the lower end of the other axial section, a cylindrical member mounted in the spray head for transmitting the rotational movement of the head to the slide member, two balls each rotatably received in one of the axial grooves of the cylindrical guide and the sinuous groove of the slide member for causing vertical upward movement of the slide member in response to rotation of the spray head, a spring for biasing the slide member in a direction tending to decrease the volume of the liquid pressurizing chamber, an inlet conduit for conducting the liquid in the receptacle to the chamber, an inlet check valve in the conduit, the spray head including a spray nozzle and a discharge valve operable for controlling discharge of liquid under spring pressure from the chamber through the nozzle in the form of a spray, a passage means for communicating the liquid pressurizing chamber with the discharge valve, and a valve mechanism for cutting off the spray immediately before the pressurized quantity of liquid is exhausted.

5. A liquid spraying device according claim 4, in which the passage means comprises a hollow stem formed of rigid material and fixed with respect to the spray head, the piston having a piston ring mounted thereon which is formed with an opening adapted to slidably receive the lower portion of the hollow stem in liquid-tight manner, the hollow stem being of such length that the piston ring leaves the lower end of the hollow stem immediately before the pistron reaches its lowermost position, the piston and cylinder having side openings formed therein, the valve mechanism being provided by the piston ring, the lower portion of the hollow stem and the two side openings.

6. A liquid spraying device according to claim 4, in which the passage means comprises a flexible tube connected at its upper end to the discharge valve and at its lower end to the piston.

7. A liquid spraying device according to claim 6, in which the valve mechanism comprises a body having a bore communicating with the receptacle through the inlet conduit, the body being held in place on the bottom of the cylinder and having a side port communicating with the bore, and a valve member mounted on the body and having a wall which is normally held against the body to close the side port, the valve member being provided with a projection which is adapted to be engaged by the lower end of the piston to force the wall away from the body to thereby open the side port immediately before the piston reaches its lowermost position.

8. A liquid spraying device according to claim 6, in which the valve mechanism comprises a valve member held in place on the bottom of the cylinder, the cylinder having at least one side openings which are normally closed by the outer surface of the valve member, the valve member being tapered at its upper periphery, the piston having an end bore converging upwardly and a plurality of grooves formed in the wall of the end bore, the end bore being adapted to slidably receive the tapered periphery of the valve member to force it inwardly to thereby open the side openings of the cylinder immediately before the piston reaches its lowermost position.

9. A liquid spraying device according to claim 6, in which the valve mechanism comprises a valve member slidably received in an end bore of the piston, the valve member being normally urged against a valve seat provided at the lower end of the piston by the action of a spring, the piston having a side opening which is normally closed by the outer periphery of the valve member, the cylinder having a side opening for communicating the liquid pressurizing chamber with the receptacle when the valve member moves away from the valve seat, the check valve including an upwardly extending projection which is adapted to engage the valve member and move it upwardly relative to the piston immediately before the piston reaches its lowermost position.

10. A liquid spraying device according to claim 6, in which the valve mechanism comprises a valve member slidably received in an end bore of the piston, the valve member being normally urged against a valve seat provided at the lower end of the piston by the action of a spring, the piston having a side opening which is normally closed by the outer periphery of the valve member, the cylinder having a side opening for communicating the liquid pressurizing chamber with the receptacle when the valve member moves away from the valve seat, the valve member having a downwardly extending projection which is adapted to engage the check valve immediately before the piston reaches its lowermost position, the valve member having an axial bore extending therethrough and at least one radially extending grooves formed at the lower end of the projection and communicating with the bore.

11. A liquid spraying device according to claim 6, in which the valve mechanism comprises a spring guide held in place on the bottom of the cylinder and having a peripheral flange, a valve member slidably received in the cylinder and biased against the undersurface of the peripheral flange by a spring received on the spring guide, the valve member normally closing at least one side openings formed in the cylinder, and a piston ring mounted to the lower end of the piston and having a plurality of legs, between which are formed a plurality of passages for communicating the liquid pressurizing chamber with the side openings immediately before the piston reaches its lowermost position.

12. A liquid spraying device according to claim 4, in which the passage means comprises a hollow stem formed of rigid material and fixed with respect to the spray head, the piston having a piston ring mounted thereon which is formed with an opening adapted to slidably receive the lower portion of the hollow stem in liquid-tight manner, the hollow stem being closed at its lower end and provided with at least one side ports adjacent the lower end, the side ports being adapted to be closed by the piston ring immediately before the piston reaches its lowermost position.

13. A liquid spraying device according to claim 6, in which the valve mechanism comprises a valve member standing in upright manner on the check valve and including a head in the shape of an umbrella, a cut-shaped member held in place on the check valve and having an opening through which the valve member extends, and a valve seat provided in an end bore of the piston.

14. A liquid spraying device according to claim 6, in which the valve mechanism comprises a support member held in place on the check valve so as not to hinder the opening movement of the check valve, a spring having its lower end secured to the support member, a conical valve member connected to the upper end of the spring, and a valve seat provided in end bore of the piston.

15. A liquid spraying device according to claim 6, in which the valve mechanism comprises a spring received in an end bore of the piston, a valve seat provided at the lower end of the end bore, and a ball normally urged against the valve seat by the action of the spring, the spring being so adjusted that the ball moves away from the valve seat when the pressure in the liquid pressurizing chamber increases above a predetermined level which is slightly higher the minimum pressure producing spray mist.

16. A liquid spraying device according to claim 6, in which the valve mechanism is provided by the lower end of the piston and the upper surface of the check valve, the lower end of the piston being tapered to form an annular space between the piston, the cylinder and the check valve when the lower end of the piston comes into liquid-tight contact with the upper surface of the check valve.