Dispensing – With discharge assistant – With movable nozzle interconnected therewith
Reexamination Certificate
2001-01-24
2001-12-25
Bomberg, Kenneth (Department: 3754)
Dispensing
With discharge assistant
With movable nozzle interconnected therewith
C222S321700, C222S321900
Reexamination Certificate
active
06332561
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an airless dispenser device such as an airless pump, i.e. a pump without any air intake, so that the substance to be dispensed never comes into contact with air until it is dispensed. Such an airless pump is used, in particular, for dispensing substances that are liable to deteriorate on coming into contact with air. Such substances can be pharmaceuticals or cosmetics.
Conventionally, that type of dispenser comprises a dispensing chamber of variable volume, which chamber is provided with an inlet equipped with an inlet valve, and is provided with an outlet equipped with an outlet valve. In order to vary the volume of the dispensing chamber, a piston is provided that is generally actuated by means of an actuator rod through which the substance is delivered from the chamber. That is a quite conventional design for an airless pump.
In order to avoid any possibility of the substance to be dispensed being deteriorated by coming into contact with air, it is preferable to fill the container under a vacuum, and to mount the dispenser device on the container while it is still under a vacuum. During the operation of mounting the dispenser on the container under vacuum conditions, the inside of the dispenser, and in particular the dispensing chamber, is also subjected to the vacuum. The air is evacuated from the dispensing chamber via the inlet valve whose valve member can be in the form of a ball, of a washer, or of a conical flange member, which valve member does not provide good airtightness during this operation of fixing the dispenser under a vacuum. The valve seat does not have a surface state that is good enough to guarantee good airtightness. Therefore, air is also evacuated from the dispensing chamber and a partial vacuum then prevails therein. It should be noted that, during this step of mounting the dispenser on the container, the dispenser head is not yet mounted on the actuator rod of the dispenser. When the vacuum is interrupted, once the dispenser has been fixed to the container, the container and the pump are once again subjected to atmospheric pressure, so that all of the empty spaces inside the container and also inside the dispensing chamber are suddenly filled with the substance contained in the container. The dispensing chamber is thus at least partially filled. A major drawback then occurs when the dispenser head is mounted on the actuator rod, since mounting the head causes the rod to be displaced, which in turn causes the piston to be displaced, thereby reducing the volume of the dispensing chamber which is at least partially filled with the substance. As a result, substance contained in the dispensing chamber is dispensed. Therefore, prior to the device being sold and being used for the first time, the actuator rod and the expulsion channel in the dispenser head are filled with substance. That substance is then naturally in contact with the outside air, and can thus deteriorate.
Attempts have been made to solve that problem of substance being dispensed while the dispenser head is being mounted. Some such attempts consist in inserting a gas into the chamber before the dispenser is returned to atmospheric pressure. However, such a method is very difficult to implement because of the small diameter of the internal channel in the actuator rod, since it is necessary simultaneously to push back the outlet valve member and to inject the gas into the chamber. Such a gas injection method is therefore very difficult to implement.
Document EP-0 753 353 discloses a dispenser whose inlet tube is formed with a stopper that closes it off. When it is used for the first time, the stopper is punched out by an extension to the actuator rod, which extension penetrates into the inlet tube. The stopper is integrally molded with the inlet tube, which complicates molding. In addition, once it has been punched out, the stopper is free to move inside the inlet tube, and there is therefore a risk that said stopper might hinder dispenser operation.
SUMMARY OF THE INVENTION
An object of the present invention is to mitigate that drawback of the prior art by defining a dispenser whose inlet is initially closed off by a stopper that is easy to put in place, without complicating the molding, and that cannot hinder dispenser operation once it has been dislodged from its closure position.
To this end, the present invention provides a dispenser device without any air intake, such as an airless pump, for dispensing a fluid substance, said device comprising a dispensing chamber of variable volume, which chamber is provided with an inlet equipped with an inlet valve member, and is provided with an outlet equipped with an outlet valve member, said dispenser further comprising a piston for causing the volume of the dispensing chamber to vary, closure means being provided to close off the dispensing chamber in airtight manner, substantially at its inlet, prior to it being used for the first time, the closure means being formed by the inlet valve member.
Since the outlet valve has good airtightness, the inlet closure means make it possible to isolate the dispensing chamber from the outside air with good airtightness. It is thus impossible for an air vacuum to establish itself inside said chamber.
Using the inlet valve member itself as closure means offers the advantage of not adding any additional parts to the dispenser.
In order for the dispensing chamber to be put back into communication with the container, the piston is mounted on an actuator rod having an end that projects into the dispensing chamber, said end forming a pusher member suitable, at the end of its stroke, for pushing the inlet valve member from its airtight position into its normal working position.
In a first practical embodiment, the inlet valve member is a ball wedged in airtight manner in a sleeve.
In a variant, the inlet valve member is a member having a conical flange and provided with a projecting peripheral sealing bead wedged in the inlet of the dispensing chamber.
Thus, the dispensing chamber is well isolated from the outside, and thus it is not subjected to the vacuum that prevails at the time of fixing the dispenser to the container. The closure means are released only on mounting the dispenser head onto the actuator rod, which causes the rod to be displaced inside the chamber until its end displaces the closure means in order to establish communication between the chamber and the container.
By using the inlet valve member to close off the inlet, it is not necessary to mold a stopper, as it is in the prior art, and, once the valve member has been dislodged, there is no danger of it hindering dispenser operation.
REFERENCES:
patent: 4457455 (1984-07-01), Meshberg
patent: 4458832 (1984-07-01), Corsette
patent: 4496082 (1985-01-01), Corsette
patent: 4524888 (1985-06-01), Tada
patent: 4538745 (1985-09-01), Dunning et al.
patent: 4696415 (1987-09-01), Meshberg
patent: 5123571 (1992-06-01), Rebeyrolle et al.
patent: 5335858 (1994-08-01), Dunning et al.
patent: 5449094 (1995-09-01), Behar et al.
patent: 5549223 (1996-08-01), Hori
patent: 5590815 (1997-01-01), Montaner et al.
patent: 498 275 (1992-08-01), None
patent: 499 520 (1992-08-01), None
patent: 696 478 (1996-02-01), None
patent: 753 353 (1997-01-01), None
Garcia Firmin
LaFosse Alain
Pennaneac′h Hervé
Bomberg Kenneth
Sughrue & Mion, PLLC
Valois S.A.
LandOfFree
Airless dispensing device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Airless dispensing device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Airless dispensing device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2589581