BRIEF DESCRIPTION OF THE DRAWINGS
1 2
ATOMIZERS communicating with the first cylinder, a second piston
„ r„ „, , slidable in the second Cylinder, valve means connected
BACKGROUND OF THE INVENTION tQ the second piston Jd tQ ... commu.
1. Field of the Invention. nication between the first cylinder and the nozzle, a This invention relates to liquid atomizers, particu- 5 first spring acting on the second piston and biasing the
larly of perfume. valve means to a position in which the said communica
2. Description of the Prior Art. tion is interrupted, a non-return valve, a plunger tube A liquid atomizer has been proposed comprising a communicating with a space defined by the two cylin
first cylinder in which a hollow piston is slidably ders through the non-return valve, the second cylinder
mounted connected to an atomization tube, a second 10 being disposed within the first piston and being mov
cylinder of smaller section than the first, which com- able with respect to the first cylinder, and a second
municates with the first cylinder and in which is slid- spring acting to bias the two cylinders apart,
ably mounted a piston connected to a valve suitable for This construction overcomes at least partially the dif
interrupting communication between the first cylinder ficulties of previously proposed atomizers, the spring
and the atomization tube, and resilient means acting on 15 interposed between the two cylinders ensuring release
the second piston and biasing the valve into the posi- of fluid with a pressure of a constant predetermined
tion in which the said communication is interrupted, value. Furthermore, the advantage arises of increasing
the assembly of the two cylinders defining a space the volume ejected by a given stroke of the larger pis
which communicates with a plunger tube through a ton.
non-return valve. 20 In one preferred embodiment of the invention in In this prior proposal, when the first piston is moved, which the atomization tube is connected by an axial it carries with it the second piston through the interme- tube to the first piston, this axial tube comprises a part diary of the valve, but the available space for liquid de- of reduced internal diameter which defines a seat and creases, since the second piston has a section which is the second piston is connected to a rod which is slidsmaller than that of the first. The pressure of the liquid 25 ably mounted in the tube and of which the end forms in the two cylinders increases so that the second piston the delivery valve, tends to move with respect to the first against the action of resilient means which act on it. When this pressure reaches a sufficient value to balance this action, FIG. 1 is a longitudinal, part-sectional view of an atthe second piston moves whilst carrying with it the 30 omizer in accordance with the invention; valve connected with it so that the cylinders are put in FIG. 2 is a longitudinal section, to an enlarged scale, communication with the atomization tube. The liquid of a part of the atomizer of FIG. 1; contained in the cylinders is thus only atomized when FIG. 3 is a section on the line HI—III of FIG. 2; and its pressure reaches a predetermined value, which FIG. 4 is a view in section of a part of the atomizer avoids the production of non-atomized drops, which 35 Gf p\Q \ a^ the end of the stroke of a push-button phenomena would occur if the cylinders were placed in thereof, communication with the tube from the start of the movement of the first piston. Similarly on the termination of the movement of the first piston, the valve interrupting communication between the cylinders and the 40 As is illustrated in the drawings, the atomizer in actube when the liquid pressure exerts on the second pis- cordance with the invention comprises a cylinder 1 ton a force lower than the return force of the resilient which has in a lower part thereof a flange la and is semeans. cured to an internally-tapped bush 2 intended to closeThe atomizers of the type hereinbefore outlined, off a receiver containing the liquid to be atomized. This have the disadvantage of difficult priming since the de- 4^ cylinder 1 communicates, at its lower part, with a livery pressure increases progressively as the hollow plunger tube 3 through a non-return valve 4. piston is plunged downwardly. Moreover, the atomizer In the cylinder 1 there is slidably mounted a hollow must include a valve preventing return to the liquid res- piston 5 secured to one of the ends of a tube 6; the ervoir which is provided in the first cylinder; this inlet other end of this tube is secured to a push-button 7 valve is generally carried by the small piston and is thus which comprises an atomization tube or nozzle 8 in movable with respect to the casing of the pump. It has communication with the said tube 6. The portion of the been established that when the delivery valve leaves its piston 5 slidably mounted in the cylinder 1 is frustoblocking position, the inlet valve has a tendency to conical and is connected through a shoulder 5a to the leave its seat, which causes return to the reservoir of a g5 portion of the said piston which is fixed to the tube 6. certain amount of liquid contained in the first cylinder; This latter portion is cylindrical and is itself slidably the loss of pressure which follows this spoils atomiza- mounted with a predetermined clearance, in a casing 9 tion. fitted in the cylinder against the edge of which the The object of the present invention in an improve- shoulder 5a can just come into abutment. In the hollow ment in atomizers of the hereinbefore described type, 6Q piston 5 a blind bushing 10 is slidably mounted which which enables ready priming of the atomizer. is closed at its end directed towards the non-return
valve 4. A spring 11 is interposed between this bushing and the bottom of the cylinder 1; it biases the bushing
According to the present invention, there is provided 10 against the end of the tube 6 and also the piston 5
in a liquid atomizer, a first cylinder, a hollow, first, pis- 65 against the cover 9. Lateral passages 12 are formed in
ton slidable in the first cylinder, an atomizing nozzle the internal face of the hollow piston 5 or, as shown, in
communicating with the hollow piston, a second cylin- the external face of the bushing 10 and openings 10 a
der of smaller cross-section than the first cylinder and formed in the internal end of this bushing, put the cylin
DESCRIPTION OF THE PREFERRED
EMBODIMENT
