Abstract:
A pump for a liquid cosmetic product dispenser including a body defining a metering chamber provided with an admission orifice at the bottom and having an opening at the top into which is inserted a sleeve carried by an axially movable operating head which is provided with a delivery duct and an open/close element and is acted upon by a return spring mounted on the outside of the body. The body encloses a jacket that moves axially inside the chamber and at least partly inside the sleeve and supports a lower valve for closing the admission orifice.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of pending International patent application PCT/FR2006/002479 filed on Nov. 7, 2006 which designates the United States and claims priority from French patent application 0553876 filed on Dec. 14, 2005, the content of which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a pump which is intended more particularly for metering and dispensing liquid cosmetic products such as creams or gels. 
     BACKGROUND OF THE INVENTION 
     The known pumps which are used in this type of application generally comprise a body which delimits a metering chamber provided in the lower part with an intake orifice and having in the upper part an opening into which there is introduced a sleeve borne by an axially displaceable actuation head which is provided with a discharge conduit and with a closure element and which moreover cooperates with a return spring mounted on the exterior of said body. 
     This arrangement makes it possible to prevent the spring, which is made of metal, from entering into contact with the product and giving rise to physico-chemical degradation phenomena. 
     The displacement of the actuation head relative to the body has a piston effect which causes the product inside the chamber to be compressed and to exit via the discharge conduit. 
     The intake orifice is for its part able to be closed off, at least during the phase of dispensing the product, by a valve which is generally a ball valve. 
     However, this valve is independent of the other constituent elements of the pump and is made in the form of parts which are attached to the body, which creates problems with regard to sealing, coordination during operation and assembly difficulties. 
     Furthermore, such a valve is subject to the forces of gravity and may fail to operate in the case when the pump is used in the inclined or inverted position. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to solve these technical problems satisfactorily. 
     This object is achieved according to the invention by means of a pump of the aforementioned type, characterised in that the body encloses a jacket which can be displaced axially in said chamber and at least partially inside the sleeve and which bears a lower valve capable of closing the intake orifice. 
     According to one advantageous feature, said jacket comprises, in the lower part, a sealing skirt which is in contact with the inner wall of the chamber. 
     According to another feature, said jacket comprises, in the upper part, a peripheral lip which is in sealed frictional contact with the inner wall of the sleeve. 
     Advantageously, said jacket comprises a peripheral shoulder capable of coming into abutment against an annular protrusion borne by the inner wall of the body in order to limit its upward travel. 
     According to one variant, said valve comprises a central cup connected to the wall of said jacket by radial fins. 
     Preferably, said cup has a cross section complementary to that of the intake orifice. 
     According to another variant, the body comprises a vent orifice which opens, in the lower part, into the chamber and is able to communicate with an annular atmospheric compartment formed at the periphery of the jacket. 
     Advantageously, said vent orifice can be isolated in a sealed manner from the atmospheric compartment by an annular flap borne by the lower part of the jacket. 
     Preferably, said flap and said skirt delimit between them a peripheral groove which covers a circular rib borne by the bottom of the chamber. 
     According to one variant, said closure element for closing the discharge conduit is associated with a control rod which can move axially in said jacket. 
     In this case, it is provided that said jacket comprises an upper collar for guiding the control rod. 
     It is also possible to provide that the inner wall of said jacket is provided with a rim for axially retaining the control rod. 
     According to another feature, the body is made in a single piece with a ring for fixing the pump to the neck of a container. 
     The pump of the invention has a simple structure which is inexpensive to produce and ensures a high level of sealing for the product. 
     It also makes it possible to ensure a reliable way of dispensing the product with a precise and reproducible dose and offers a high degree of adaptability and cooperation with different variants of actuation heads with end closures. 
     The pump of the invention applies both to an atmospheric dispenser and to an airless dispenser. 
     In an atmospheric application, the air return takes place in an original manner which presents all the necessary guarantees with regard to sealing and regularity. 
     In an airless application, and depending on the type of container used, the pump may not comprise a vent orifice. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects and advantages of the invention will emerge in the course of the following description, which is given with reference to the appended drawings, in which: 
         FIG. 1  shows a sectional view of a first embodiment of the pump of the invention; 
         FIG. 2  shows a sectional view of a second embodiment of the pump of the invention; 
         FIGS. 3A to 3F  show schematic views of the various phases of delivering the product with a pump according to the embodiment of  FIG. 1 ; 
         FIGS. 4A and 4B  show partial perspective views, respectively from above and from below, of the embodiment of  FIGS. 1 and 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The pump of the invention comprises, as shown in  FIGS. 1 and 2 , a generally cylindrical body  1 , the wall of which delimits internally a metering chamber. 
     In the embodiment of  FIG. 1 , the body  1  is mounted in a ring B which is designed to be fixed to the neck of a product reservoir which is in the form of a bottle or more generally a cylindrical container (not shown). 
     In the variant of  FIG. 2 , the ring B is made in a single piece with the body  1 . 
     The metering chamber of the pump is provided, in the lower part, with an intake orifice  10  which is extended downwards into the reservoir by an intake tube  15 . The chamber has, in the upper part, an opening into which there is introduced a sleeve  21  borne by an actuation head  2 . 
     The head  2  forms an axially displaceable push-button, and the sleeve  21  is covered by a shrunk-fit section or cap  22 . 
     The lower perimeter of the sleeve  21  is provided with radial retaining protrusions  23  which cooperate with an upper collar  14  of the body  1  so as to prevent the separation of the pump and its head  2 . 
     A manual push by the user on the upper face of the cap  22  of the head  2  causes the latter to descend, while its return to the top position is brought about by a return spring R mounted coaxially outside the body  1  and the sleeve  21 . 
     The head  2  is moreover provided with a conduit  20  for discharging the product, said conduit being supplied at the upstream end by the metering chamber and opening to the outside at the downstream end. 
     The conduit  20  is provided with a closure element  4 , for example in the form of a valve which is arranged at the upstream end in the embodiment of  FIG. 1  and is arranged at the downstream end of said conduit in the embodiment of  FIG. 2 . 
     According to the invention, the body  1  encloses a cylindrical jacket  3  which can be displaced axially in the chamber and at least partially inside the sleeve  21  and bears a lower valve  30  capable of closing off the intake orifice  10 . 
     The jacket  3  also comprises, in the lower part, a sealing skirt  31  which is in contact with the inner wall of the chamber. 
     In  FIG. 2 , the bottom of the chamber bears a circular rib  13  which extends around the orifice  10  and against the inner face of which the lower edge of the skirt  31  bears in a sealing manner. 
     In the upper part, the jacket  3  comprises a peripheral lip  32  which is in sealed frictional contact with the inner wall of the sleeve  21  and which, as it slides, also performs scraping of the product. 
     The internal volume of the jacket  3  and that of the sleeve  21  up to the entrance of the discharge conduit  20  constitutes the volume of one dose of product. 
     The intake valve  30  comprises a central cup  30   a  connected to the wall of the jacket  3  by a set of radial fins  30   b , as shown in  FIG. 4B . The cup  30   a  preferably has a cross section complementary to that of the intake orifice  10  and has for example here a frustoconical shape or else, according to a variant which is not shown, a spherical shape. 
     In the case of atmospheric applications, such as for the embodiments of  FIGS. 1 and 2 , the body  1  of the pump comprises a vent orifice  11  which opens, in the lower part, into the chamber and is able to communicate with an annular compartment  33  formed at the periphery of the jacket  3  between its outer wall and the inner wall of the body  1 . 
     The vent orifice  11  can be isolated in a sealed manner from the compartment  33 , in particular when the pump is at rest and during the phase of delivering the product, by an annular flap  35  borne by the lower part of the jacket  3 , as shown in  FIGS. 4A and 4B . 
     In the embodiment of  FIG. 2 , the flap  35  and the sealing skirt  31  delimit between them a peripheral groove  12  which covers the circular rib  13  of the bottom of the chamber. 
     The jacket  3  comprises a peripheral shoulder  36  capable of coming into sealed abutment against an annular protrusion  16  borne by the inner wall of the body in order to limit the upward travel of said jacket (see  FIGS. 2 ,  4 A and  4 B). 
     In the embodiment of  FIG. 2 , the area between the lower end of the flap  35  and the shoulder  36  ensures the axial orientation of the jacket  3  in the chamber. 
     In the embodiment of  FIG. 1 , the flap is very short and it is therefore its upper face which delimits the shoulder  36 . 
     In the two embodiments of  FIGS. 1 and 2 , the closure element  4  is associated with a control rod  41  which can move axially in the jacket  3 . However, other types of valve would also be suitable, such as a spring valve for example. 
     In the embodiment of  FIG. 1 , the closure element  4  is a valve, the seat of which is formed by a frustoconical area formed in the upper part of the sleeve  21  and which moreover forms a shoulder forming an upper stop for the jacket  3 . 
     In the embodiment of  FIG. 2 , the closure element  4  is a retractable needle valve  42  in the conduit  20 . 
     The jacket  3  comprises an upper collar  37  for guiding the rod  41 , and the latter has a diameter smaller than the inner diameter of the central bore  34  of the jacket  3  so as to allow the passage of the product being dispensed. 
     According to one variant, the passage of the product may also be provided via longitudinal grooves formed on the rod  41 . 
     However, the inner wall of the jacket  3  is provided with a rim  34   a  for axially retaining the end of the rod  41  which has a chamfered cross section in  FIG. 2 . 
       FIGS. 3A to 3F  illustrate the successive phases of delivering the product with the pump of the invention in the atmospheric version according to the variant of  FIG. 1 . For the sake of clarity, the liquid product is not shown in these figures. 
     The position shown in  FIG. 3A  corresponds to the rest position of the pump. 
     In this position, the chamber is filled with product and, due to the abutment of the protrusion  23  against the collar  14 , the spring R remains slightly compressed so as to keep the head  2  towards the top and consequently to keep the closure element  4  bearing in a sealed manner against its seat. 
     The sealing effect is reinforced by the fact that the end of the rod  41  of the element  4  is drawn downwards due to the fact that it is hooked onto the rim  34   a.    
     The jacket  3  is in the upper position here and the intake valve  30  is open. 
     The peripheral shoulder  36  bears in a sealed manner against the lower face of the annular protrusion  16 , thus preventing any exchange between the interior of the container and the exterior. 
     The position shown in  FIG. 3B  corresponds to the start of the phase of pressing down on the head  2 , the force of which is illustrated by an axial arrow. 
     The frictional contact between the lip  32  of the jacket  3  and the inner wall of the sleeve  21  keeps together the assembly consisting of the two parts and the closure element  4  in their joint descending movement. 
     The slight hold resulting from this contact nevertheless provides a resistance greater than the hold between the skirt  31  and the wall of the body  1 . 
     Following this movement, the valve  30  closes the intake orifice  10  and thus prevents the product contained in the chamber from returning to the container. 
     In parallel, the flap  35  clears the vent orifice  11  and thus allows it to communicate with the annular compartment  33 , which is itself in communication with the exterior. 
     In  FIG. 3C , the user continues to press down and the head  2  thus continues its descent, while the jacket  3  bears against the bottom of the chamber. 
     The frictional resistance of the contact between the jacket  3  and sleeve  21  is overcome and gives way to a sliding motion which scrapes the lip  32  against the inner wall of the sleeve while the latter continues its downward travel. 
     This movement causes the compression of the product in the chamber in the manner of a piston and causes the closure element  4  to come away from its seat so as to liberate the product which thus starts to escape through the conduit  20 . 
     In  FIG. 3D , while the user continues to push down, the closure element  4  is pressed in the open position at the top against the inner wall of the conduit  20  and/or the cap  22 . 
     The sleeve  21  continues its downward travel while compressing the product in the chamber until the upper edge of the jacket  3  (lip  32  or collar  37 ) comes into abutment against a shoulder  24  of the head. 
     At this moment from the chamber, a volume corresponding to one dose of product has been delivered to the user and the dispensing phase is terminated. 
     The vent orifice  11  communicates with the compartment  33 , which allows the product reservoir (not shown) to reach atmospheric pressure and allows an equalisation of the pressures. 
     The user then releases the pressure and the spring R returns the head  2  to the top as shown in  FIG. 3E . 
     Due to the frictional contact between the lip  32  and the wall of the sleeve  21 , the jacket  3  and the head  2  initially ascend together with the valve  30  which leads to the opening of the intake orifice  10 . 
     The vacuum created in the body of the pump as a result of this displacement causes product to be sucked into the reservoir via the intake tube  15  and causes the gradual filling of the metering chamber. 
     At the same time, the vent orifice  11  is closed as a result of the flap  35  again coming into contact with the inner wall of the body until its upper face forming the shoulder  36  comes into abutment against the protrusion  16  of the body. 
     Very quickly, however, the resistance of the lip  32  is overcome and the sleeve  21  continues its upward travel independently of the jacket  3  which remains blocked in the bottom position by the stop  16  of the body. 
     The closure element  4  then returns to its sealing position and thus closes the conduit  20  as shown in  FIG. 3F , and during this phase the chamber continues to fill with product. 
     Still under the action of the spring R, the head  2  continues its upward travel and finally stops in the rest position of  FIG. 3A  to await a new dispensing phase. 
     In this latter position, the conduit  20  is kept in a sealed closed position due to the action of the spring R and the fact that the rod  41  of the element  4  is drawn downwards by the rim  34   a.    
     Of course, this pump may also be produced without a vent orifice in the case of an airless use.