DESCRIPTION The present invention relates to a sprayer device, in particular a pump sprayer actuated manually by means of a trigger lever.

Reference will be made in particular herein below to sprayers of liquid, without detriment to the fact that these sprayers can be used also for spraying any type of fluid, such as for example foams or the like.

A sprayer of this type generally comprises a main body provided with a base with a threaded ring nut to be attached to the mouth of a container of liquid, a delivery nozzle wherefrom the liquid is sprayed, a trigger lever which can be actuated by hand by the user and strained by a spring, and a pump which can be actuated by the trigger lever to suck the liquid from the container and spray it through the delivery nozzle.

The pump provides a piston acting in a chamber formed in the body of the sprayer. The body of the sprayer comprises moreover an inlet duct which puts the interior of the fluid container in communication with the chamber of the pump and an outlet duct which puts the chamber of the pump in communication with the nozzle of the sprayer.

A valve for fluid suction and delivery is normally provided inside the chamber of the pump, suitable for allowing, in a selective and one-way manner, the suction of the fluid from the container to the chamber of the pump and the delivery of fluid from the chamber of the pump towards the delivery nozzle.

Such a type of valve is somewhat delicate and therefore subject to jamming and blocking of the channels of suction and delivery, with the result of making the sprayer unusable.

Other systems of valves, currently less used, provide balls in the ducts of delivery of the liquid which open and close the passage opening of these ducts during actuation of the pump.

Sprayers with these systems of valves are excessively complex and are made in a large number of components, also of different materials, and not therefore recyclable.

Moreover the intervention of the ball, which acts through the force of gravity, is not instantaneous and influences the use of the trigger when used in a tilted position, to the extent of invalidating functioning of the sprayer in a horizontal position, in that the ball does not succeed in closing tightly the suction orifice,

US 2001/0030246 Al discloses a hand lever-operated spray pump with a deliveiy valve arranged at the deliveiy nozzle. The actuation of the hand lever causes the buckling of two bridge sections of the pump housing connecting two hinge sections.

The object of the present invention is that of eliminating the disadvantages of the prior art, providing a sprayer device with trigger-operated pump which is extremely reliable and suitable for ensuring perfect functioning, avoiding the problems of faults and jamming of the pump valve.

Another object of the present invention is that of providing such a sprayer which is made up of a limited number of component parts and is therefore simple and economical to manufacture.

Yet another object of the invention is that of providing such a sprayer whose component elements are made in materials compatible with the aims of industrial recycling.

These objects are achieved, in accordance with the invention, with the features listed in the annexed independent claim 1.

Advantageous applications of the invention are disclosed by the dependent claims.

The sprayer with trigger lever according to the invention substantially comprises a body which can be attached to a container of liquids by means of a screw ring nut and is provided with a spraying nozzle placed at the end of a hollow stem holding at the other end a plunger sliding in a pumping chamber formed in the body of the sprayer. The pumping chamber is in communication with the container via a hole provided to the rear of the same, wherein a one-way mushroom suction valve is placed, and in communication with the spraying nozzle via holes formed in the plunger and said hollow stem. The plunger is mounted on the hollow stem in such a way that one of its lips abuts tightly on the inner wall of the stem preventing, in certain conditions, the passage of fluid through the aforesaid holes formed in the plunger, thus acting as delivery valve, In rest conditions the pumping chamber is full of liquid and the suction and delivery valves both closed.

Actuating the trigger lever produces the backward movement of the plunger and the compression of the liquid in the pumping chamber, which on the one hand keeps the mushroom suction valve closed and on the other causes the opening of the delivery valve, allowing the outflow of the liquid towards the spraying nozzle through the holes formed in the piston.

When the trigger lever is released, the plunger moves in an opposite direction, creating a vacuum in the pumping chamber which keeps the delivery valve closed and opens the suction valve, drawing liquid into the chamber.

Conveniently all the components of the sprayer are formed in plastic material, including the return spring of the trigger lever, which conveniently is integral with the same.

The plastic material used is preferably polypropylene and/or polyethylene, so that the entire sprayer is recyclable and possibly biodegradable.

Further features of the invention will be made clearer by the following detailed description, referred to one of its embodiments purely by way of a non-limiting example, illustrated in the accompanying drawings, in which:

Fig. 1 is a median sectioned view of a sprayer according to the invention, shown during the suction phase;

Fig. 2 is a sectioned view of the sprayer in condition of non-use after the suction phase; Fig. 3 is a sectioned view of the sprayer in condition of delivery;

Fig. 4 is a sectioned view, like those of the previous drawings, of only the plunger of the pump of the sprayer;

Fig. 5 is a section taken along the plane V-V of Fig. 4. Referring to these drawings, the sprayer according to the invention has been denoted as a whole by reference numeral 10. At the base of the sprayer 10 an attachment ring nut 11 is rotatably mounted which has internal threading suitable for engaging with an external threading of the mouth of a container (not shown) suitable for containing a liquid, such as for example liquids for cleaning the home and the like,

The ring nut 11 is mounted on a lower cylindrical protuberance 12 of the sprayer body 14, formed in a single part and also including the external casing.

The sprayer 10 comprises a trigger 29 hinged in one of its ends 30 to the body 14 of the sprayer and in one of its intermediate portions 31 to a hollow stem 32 of a plunger 33 sliding horizontally and tightly inside a chamber 20 defined in the body 14 of the sprayer. At the other end of the hollow stem 32 a delivery nozzle 15 is positioned, whereon a spraying ring nut 16 is mounted, whose actuation, in a manner in itself known, enables or disables the exit of the liquid.

Between the trigger lever 29 and the body 14 of the sprayer a spring 60 is interposed which strains the trigger 29 towards an advanced forward rest position.

More particularly the spring 60 is a spring of the leaf type having a C configuration and is formed in a single part with the trigger lever 29, and its free end 61 goes to abut against a shoulder 62 formed in the body 14 of the sprayer, to the rear and above the chamber 20 for sliding of the plunger.

The chamber 20 has a rear vertical wall 21 (in actual fact in the embodiment shown in the drawings this wall is slightly forward with respect to the base wall of the chamber 20) provided with a hole 34 for entry of the liquid, communicating with a substantially vertical duct 37 formed in the body 14, in which a dipper tube 36 is housed.

In the entrance hole 34 a button or mushroom 39 is placed, acting as one-way suction valve, as will be explained herein below,

In the plunger 33, which is mounted by forcing on the end of the hollow stem 32, holes 35 are formed for exit of the liquid, substantially in line with the circular edge 40 of the hollow stem 32 (see also Fig. 5).

From the plunger 33 projects a circular lip 41 which goes to position against the inner wall 42 of the hollow stem 32, also acting as one-way valve, as will be explained herein below.

In the lower part of the chamber 20, aligned with the plunger 33, when the latter is in rest position (Fig. 2), a hole 44 for recovery of air is provided in a manner in itself known,

A brief description is now given of the functioning of the sprayer 10 according to the invention. In an initial, or rest, condition, shown in Fig. 2, the pumping chamber 20 of the plunger is full of liquid and the plunger 33 is in a distal position from the mushroom valve 39.

When the user presses the trigger lever 29, compressing the spring 60 (Fig. 3), the plunger 33 moves into the chamber 20 towards the mushroom valve 39, which is held in position of closure against the rear vertical wall 21 ₅ plugging the entiy hole 34.

The liquid in the chamber 20 is therefore forced to pass through the holes 35 of the plunger 33, and the pressure of the same tends to distance the lip 41 from the inner wall 42 of the hollow piston 32, creating an annular gap through which the liquid enters the hollow stem 32 and moves towards the deliveiy nozzle 15, through the duct 43 formed in the hollow stem as indicated by the arrows in Fig. 3.

When the trigger lever 29 is released, it returns into the starting position under the action of the spring 60, returning the plunger 33 into a distal position from the mushroom valve 39.

As shown in Fig. 1, during this movement, the lip 41 of the plunger returns tightly against the inner wall 42 of the hollow stem 32, and the plunger creates a vacuum in the chamber 20, opening the mushroom valve 39 and sucking liquid from the container through the hole 34, as shown by the arrows in Fig. 1 , filling the chamber 20 when the plunger arrives at end of travel a in distal position from the valve 39 (Fig. 2).

During this return travel by the plunger 33, before it reaches the position shown in Fig. 2, the hole 44 remains free and allows the entiy of air inside the container so as to recover the exit of the liquid. At the end of travel the plunger 33 covers the hole 44, preventing the exit of liquid through it in the event of overturning of the container. From what is disclosed the advantages of the sprayer according to the invention appear clear, which sprayer has a considerably simplified structure, being made up of very few component parts and namely: body 14, valve 39, valve-fitted plunger 33, hollow piston 32, spraying ring nut 16, trigger lever 29 with spring 60. To make the sprayer 10 ready for application to a container, the ring nut 11, a sealing gasket 15 and the dipper tube 36 are also provided.

It is likewise possible to reduce further the number of components, eliminating the bottle ring nut 11 and the gasket 15, making the pump body 14 with integrated a system of bayonet hooking according to the prior art,

All the aforesaid components are formed in compatible materials, such as polypropylene and polyethylene, therefore completely recyclable without separation of the same and possibly biodegradable.

Naturally the invention is not limited to the particular embodiment previously described and illustrated in the accompanying drawings, but numerous detail changes can be made thereto within the reach of the person skilled in the art and in any case coming within the scope of the invention defined by the annexed claims.