Abstract:
A fluid product dispenser includes: a fluid product tank, a dispenser part comprising a pierced membrane connected directly to the tank, a mechanism to vibrate the pierced membrane, and an actuator button to activate the vibration mechanism. The tank is located above the pierced membrane such that the fluid product is supplied to the membrane from the tank using the force of gravity under normal operating conditions. The membrane is connected to the tank by a passage provided with an inlet valve capable of opening and cutting off the passage selectively.

Description:
This application claims the benefit under 35 U.S.C. §119(e) of U.S. provisional application Serial No. 60/273,043, filed Mar. 2, 2001, and priority under 35 U.S.C. §119(a)-(d) of French patent application No. FR-01.01620, filed Feb. 7, 2001. 
    
    
     TECHNICAL FIELD 
     The present invention relates to fluid product dispenser comprising a tank of fluid product and vibrating membrane that serves as a dispenser part. In general, the vibrating membrane is pierced with one or more dispenser holes through which the fluid product is dispensed under the effect of the vibration of the membrane. Means of vibration are generally provided in order to vibrate this pierced membrane: a piezoelectric part can constitute good vibration means to vibrate the membrane. 
     BACKGROUND OF THE INVENTION 
     The present invention relates more particularly to the cosmetics, perfume or pharmaceuticals sectors. The dispenser is therefore small enough to enable the user to take hold of it with a single hand. The user should also be able to actuate the dispenser with a single hand by pressing an actuator button intended to actuate the vibration means of the membrane. 
     In a standard pump that operates using suction and back-flow techniques, the pressure inside the tank does not act directly on the pump operation. A standard pump can operate with a tank that is pressurized or under vacuum, provided that excessive values are not reached. This is not the case with a pierced vibrating membrane that has neither an inlet nor an outlet valve. Consequently, the fluid product must be supplied to the vibrating membrane under pressure that is more or less equal to that of the atmosphere. A very slight vacuum or overpressure is, however, acceptable. If the tank is under pressure fluid product may leak through the holes in the pierced membrane, which would result in unacceptable seepage. On the other hand, a vacuum inside the tank would cause air to penetrate the dispenser through the holes of the pierced membrane. The spray would also be very poor quality. 
     In European Patents 0 615 470 and 0 696 234 fluid product dispensers are described that comprise a tank and a pierced membrane that vibrates by means of a piezoelectric part. Fluid supply means are provided that connect the tank to the membrane in order to supply the pierced membrane from the tank. As the pierced membrane is located above the tank under normal operating conditions it is necessary for the fluid to ascend against the force of gravity. In order for this to be possible, the supply means are capillary conduits in which the fluid products ascend naturally until they reach the pierced membrane. 
     However, it is not always easy to control the supply due to the fact that it uses capillarity. 
     BRIEF SUMMARY OF THE INVENTION 
     Consequently, the aim of the present invention is to overcome the above-mentioned drawbacks of the prior art due to capillarity by using another type of fluid-product supply from the tank to the vibrating membrane. 
     In order to achieve this, under normal operating conditions the tank is located above the pierced membrane such that the fluid product is supplied to the membrane from the tank using the force of gravity. The supply to the membrane therefore no longer depends on specific physical characteristics, i.e. capillarity, that cause the product to be dispensed at random. Gravity ensures that the membrane is directly and reliably supplied with fluid product under pressure that is more or less equal to that of the atmosphere. The term “under normal operating conditions” implies the period during which the button is actuated to activate the means of vibration. In other words, in the invention the tank is located above the membrane when the actuator button is depressed. 
     Advantageously, the dispenser includes a bottom that is intended to come into contact in the rest position with a surface that is more or less horizontal, the tank then being located above the vibrating membrane. 
     According to another advantageous characteristic, the membrane is connected to the tank by a passage provided with an inlet valve capable of opening and cutting off the passage selectively. 
     The vibration means and inlet valve are preferably electrically controlled. The inlet valve enables the membrane to be isolated from the tank such that said membrane is not subjected to any pressure. Any risk of the fluid product leaking or seeping through the holes of the pierced membrane is therefore avoided. Advantageously, the inlet valve only opens in periods during which the dispenser is actuated, i.e. when the actuator button is depressed. For example, the actuator button can activate the vibration means and open the inlet valve simultaneously. The pierced membrane is only therefore supplied with fluid product in the periods during which the dispenser is actuated. 
     According to another characteristic of the invention, the tank includes an upper section provided with an venting passage. Advantageously, the venting passage comprises a part made of porous material. The venting passage ensures that the pressure of the fluid product inside the tank is always more or less the same as atmospheric pressure. Furthermore, the passage is positioned at the top of the dispenser to prevent the fluid product from leaking through said passage. 
     According to another characteristic, the actuator button is located in the upper section of the tank and the venting passage is formed around said actuator button. The venting passage is also formed between the actuator button and the upper section of the tank. Advantageously, the actuator button masks the part made of a porous material. The actuator button is therefore used to both create and mask the venting passage. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood from the following detailed description. The description is of an embodiment of the invention given as a non-limitative example and refers to the attached single figure showing a vertical transversal section through a fluid product dispenser of the invention. 
    
    
     DETAILED DESCRIPTION 
     The dispenser comprises a base  1  onto which a tank  2  is mounted. 
     Base  1  constitutes a shell in two sections,  10  and  12 , the peripheries of which are connected together by a clip system  13 . The horizontal, transversal cross section of base  1  may be any shape, for example circular, elliptical or polygonal. The vertical cross section of the base is relatively flat and the lower shell section  10  comprises a bottom  11  on which the dispenser can stand such that it is stable. Base  1  comprises an aperture  14  in which a vibrating membrane  3  is housed. Aperture  14  can be located on the junction line between lower shell section  10  and upper shell section  12 . Upper shell section  12  also constitutes a large aperture in which tank  2  is contained. In order to hold tank  2  in the aperture upper shell section  12  includes a retaining edge  15  capable of holding tank  2  onto base  1 . 
     Base  1  also contains an inlet valve  4 , an electromagnet  5 , one or more batteries  6  and an electronic control system  7 . 
     Tank  2  comprises a bottom  22  and a dome  20  the peripheries of which,  24  and  25  respectively, are connected together with a seal  26  which may be inserted between them to ensure leaktightness. Tank  2  thus created is held in the upper shell section  12  at peripheries  24 ,  25 . Dome  20  comprises an upper section  21  that constitutes the top of the dome. According to the invention upper section  21  is provided with an aperture  210  formed by a small sleeve  211 . A part made of porous material  91  is inserted into small sleeve  211  and blocks the passage while still letting air through. A venting passage is thus created through which the outside air may penetrate the inside of the tank as the fluid product is dispensed through pierced membrane  3 . According to another characteristic of the invention an actuator button  9  is also provided on aperture  210  of upper section  21  of dome  20 . The actuator button  9  may be a tactile contactor. Button  9  is located immediately above porous part  91  and, with small sleeve  211 , defines a venting passage  92  that enables the outside air to come into contact with porous part  91 . The venting passage is thus formed around button  9  and also masks porous part  91 . It should also be noted that button  9  is ideally positioned facing bottom  11  on which the dispenser may stand on a more or less horizontal surface. 
     Button  9 , which may be an electric switch, is connected to electronic control system  7  by a flat-track feed line  8  which may run around dome  20  and pass through base  1  through retaining edge  15 . Therefore, depressing button  9  closes the electrical circuit and supplies the electronic control system. 
     Bottom  22  of tank  2  forms an outlet aperture  23  extended by a fluid product supply passage  27  that defines a first section of passage  271  directed downwards, slightly downstream of outlet aperture  23 . This first section of passage  271  is defined by tubing  230  that is constituted by bottom  22  of the tank. Tubing  230  is also connected to a body of valve  40  that defines a connector sleeve  46  on tubing  230 . Beyond first section of passage  271  the body of valve  40  defines a second section of passage  272  where an inlet valve  4  is constituted. Said inlet valve  4  is an electromagnetic valve comprising a ferromagnetic core  41  located in second section of passage  272 , one end of which is blocked by a plug  45 . Electromagnet  5  is located immediately behind plug  45  such that it can induce an electromagnetic field as far as ferromagnetic core  41 . A valve ball  43 , made of steel for example, is also held on a seat  44  constituted by body  4  by spring  42 . Consequently, in the rest position, i.e. when there is no power supply to the electromagnet  5 , ball  43  ensures the leaktightness of seat  44  and therefore isolates vibrating membrane  3  from tank  2 . On the other hand, as soon as there is power supply to electromagnet  5  ferromagnetic core  41  becomes magnetic and draws valve ball  43  which then moves against the effect of spring  42  to be released from its seat  44  and creates a connection between second section of passage  272  and a subsequent section of passage  273  which is in direct contact with a gap  274  located in contact with the holes of passage  30  of pierced membrane  3 . 
     According to the invention, pierced membrane  3  is supplied directly with fluid product from tank  2  due uniquely to the force of gravity when inlet valve  4  opens. The membrane may then be seen as being in direct contact with the fluid product from the tank because passage  27  can be considered a section or extension of the tank and therefore constitutes a part of the surface of the tank. Embodiments may be designed in which the membrane is located directly in the zone around the tank. In other words, the membrane is directly, continually and permanently connected to the tank when the valve is open. This is possible due to the fact that tank  2  is located above pierced membrane  3  when the dispenser is held in the position shown in the single figure, i.e. with the bottom directed downwards and the actuator button directed upwards. It is possible to supply fluid product using the force of gravity due to the direction of the supply passage  27 , first section  271  of which extends downwards and sections  272  and  273  of which extend horizontally towards pierced membrane  3 . To ensure that the device operates correctly, i.e. that there is a high quality of spray from pierced membrane  3 , inlet valve  4  must be open in the periods during which the dispenser is actuated. On the other hand, it is advantageous for pierced membrane  3  to be isolated from tank  2  when the dispenser is in the rest position in order to avoid any leakage or seepage through holes  30  of pierced membrane  3 . In a practical embodiment, button  9  can be used to switch on both the electronic control system of piezoelectric part  34  and electromagnet  5  simultaneously such that the valve opens at the same time as the product is sprayed through the membrane. When the valve is opened the passage creates direct, continuous contact from the tank to the pierced membrane that thus constitutes a part of the tank surface with its inner surface. 
     The invention enables a vibrating, pierced membrane to be supplied with fluid product from a tank under pressure approximately equal to that of the atmosphere and without the risk of the membrane leaking when the dispenser is in the rest position.