EP0983123B1 - Articulated piston pump - Google Patents

Abstract

The invention concerns a pump comprising a substantially cylindrical body (1) defining internally a metering chamber (11) whereof the lower end (1a) is provided with an intake orifice (10) equipped with a valve (12) and the upper end is provided with an outlet (20a) and closed by a piston (2) capable of moving in said chamber (11) by cooperating with elastic return means (4) outside the chamber (11), between a support up stop and a limit down stop. Said piston (2) comprises a central core (21) integral with the bottom end (23a) of a hollow axial rod (23) whereof the top end (23b) projects outside the metering chamber (11) and a coaxial sleeve (22), connected to said rod (23) by an elastic articulation (24) ensuring a sealed contact with the chamber (11) internal wall and defining with said core (21) a ring-shaped evacuating conduit (20) capable of being opened by displacement of said sleeve (22) with respect to the core (21), and the pump body (1) upper part being closed by a flange (3) whereof the internal surface forms the piston (2) up stop and the external surface serves as bottom support for the elastic return means (4). Said flange (3) is provided with an axial bore (30) wherein moves the hollow rod (23) integral with the piston. The invention is characterized in that said sleeve comprises a top ring (22b) designed to be urged into sealed engagement in a peripheral groove (31) arranged in said flange (3) internal surface.

Description

The present invention relates to a pump and more specifically a pump for delivering sprayed perfumes or cosmetics or low doses of pharmaceuticals.

A pump according to the preamble of claim 1 is known from document EP-A-691161.

There are pumps comprising a body substantially cylindrical intended to be fixed on a container and delimiting internally a dosing chamber for the product to be dispensed. The lower end of the body has an intake port equipped with a valve and its upper end is, on the one hand, provided an exhaust port and, on the other hand, closed by a piston. This piston is likely to move in the metering chamber, cooperating with elastic return means, between a high stop of rest and a low limit stop.

Upon priming, the first descent of the piston causes a flushing and then rising causes the filling of the chamber dosage by product.

The following displacements of the piston are accompanied, at the lowering, of a spray of product outside, via the orifice exhaust, under the effect of hydraulic pressure, and, on ascent, aspiration of product into the chamber via the intake port.

However, the pumps known so far have a large number of parts and their assembly requires operations complex and delicate, in particular, for small pumps dimensions that are difficult to implement automatically and carry on.

This results in productivity problems as well as returns and packaging costs too high.

In addition, either these pumps include seals in elastomeric material which cause odor nuisance for the product, in particular, when the latter is scented, or they not understand, and the seal is not sufficient, in particular, to very volatile products.

In addition, when these pumps are used in position inverted, i.e. upside down, the seal is no longer ensured and product leaks appear.

The object of the present invention is to resolve so satisfactory the technical problems posed by the prior art.

This object is achieved, in accordance with the invention, by means of a pump of the type comprising a substantially cylindrical body internally delimiting a metering chamber whose end bottom is provided with an inlet port fitted with a valve and the upper end of which is provided, on the one hand, with an orifice exhaust and is, on the other hand, closed by a piston capable of move in said room, cooperating with means of elastic return outside the chamber, between a high rest stop and a bottom limit stop, said piston comprising a core central integral with the lower end of an axial hollow rod whose the upper end projects outside the metering chamber and a coaxial sleeve, connected to said rod by an elastic joint ensuring, on the one hand, a tight contact with the internal wall of the chamber and delimiting, on the other hand, with said core, a conduit annular evacuation likely to be opened by displacement of said socket relative to the core and the upper part of the body pump being closed by a flange, the internal face, on the one hand, forms the upper stop of the piston and the external face, on the other hand, serves lower support for the return means; said collar being provided with an axial bore in which the hollow hollow rod moves of the piston, characterized in that said sleeve comprises a crown upper intended to come sealingly engage in a groove peripheral formed on the internal face of said collar.

According to an advantageous characteristic, said socket comprises a flared lower skirt whose inner face facing the core is provided with a peripheral ring intended to be, in the closed position of the discharge conduit, in sealed contact with said core.

According to a particular embodiment, said articulation has a central collar mounted by radial tightening on the periphery of said axial hollow rod and connected to the bushing by a spacer elastically deformable.

According to another variant, the collar consists of a central sleeve provided with a latching member in the part upper body and a peripheral flange for fixing to the rim superior of said body.

According to a specific embodiment, said hollow rod and said core are made in one piece.

According to a first variant, said hollow rod is separated from the core by transverse channels supplied by the conduit discharge.

According to a second variant, said axial hollow rod is connected, externally to the dosing chamber, to a spray tube.

Preferably, the spacer of the socket joint is arranged substantially opposite the outlet of the transverse channels and includes bodies.

Preferably, the spray tube carries a peripheral shoulder delimiting an upper bearing face for the return means of the piston.

According to another variant, said shoulder extends towards the bottom by a cylindrical wall moving in a guided manner in said central sleeve of the collar which defines with said wall a housing for said return means.

According to other characteristics, the body has an orifice forming a vent located, in the high position of the piston, above the edge bottom of the socket.

Furthermore, provision can be made for said socket to have a bevelled end ensuring a tight and scraping surface contact with the internal wall of the dosing chamber.

According to yet another variant, the lateral face of the core and the internal face opposite the socket are parallel and inclined by relative to the axis of the pump.

Preferably, said core has a lower part frustoconical likely to be housed in a profile cavity complementary formed in the lower part of the body, under the level of the lower stop of the piston, to allow forced opening from the discharge pipe to the priming.

The pump of the invention has a very tight degree of tightness raised without the use of a joint, which makes it compatible on the olfactory level with perfumes and perfumed cosmetics.

The tightness obtained is such that the pump of the invention can be used inside out without causing any product leakage.

The assembly of the various components of the pump can be carried out in a simple and unique operation, which allows a complete automation of the manufacturing and conditioning and results in productivity gains.

In addition, the piston return means are placed at the outside of the dosing chamber, which reduces the size of the part of the pump body internal to the container and pack more product in a container of the same volume.

• la figure 1 représente une vue en coupe d'un mode de réalisation de la pompe de l'invention au repos, en position de fermeture ;
• les figures 2a et 2b représentent des vues en coupe respectivement intégrale et de détail de la pompe de la figure 1 en position d'ouverture, pendant une phase de pulvérisation ;
• la figure 3 représente une vue en coupe de la pompe de la figure 1 en fin de pulvérisation ;
• les figures 4a et 4b représentent des vues en coupe respectivement intégrale et de détail de la pompe de la figure 1 en phase d'amorçage.

The invention will be better understood on reading the description which follows, accompanied by the drawings in which:

• Figure 1 shows a sectional view of an embodiment of the pump of the invention at rest, in the closed position;
• Figures 2a and 2b show respectively integral and detailed sectional views of the pump of Figure 1 in the open position, during a spraying phase;
• Figure 3 shows a sectional view of the pump of Figure 1 at the end of spraying;
• Figures 4a and 4b show respectively integral and detailed sectional views of the pump of Figure 1 in the priming phase.

The pump shown in Figure 1 is intended for the distribution of perfumes or cosmetic and pharmaceutical products from a container.

This pump comprises a substantially cylindrical body 1 internally delimiting a metering chamber 11.

The pump body 1 is intended to be sealed on the neck C of the container.

The lower end 1a of the body 1 is provided with an orifice inlet 10 fitted with a valve 12, here in the form of a ball.

The upper end 1 of the body 1 is made open for allow the introduction of a piston 2 and is provided with an orifice exhaust 20a.

The orifice 20a opens into a closable conduit 20 for the evacuation of the product from chamber 11.

The piston 2 is capable of moving in the chamber 11 between a high rest stop and a low end stop, in being returned to the rest position by a helical spring 4 disposed at outside of room 11.

The piston 2 comprises a central core 21 integral with the lower end 23a of an axial hollow rod 23 whose end upper 23b protrudes outside the chamber 11.

In the embodiment shown, the rod 23 and the core 21 are made in one piece.

The core 21 is surrounded coaxially by a socket 22 made in the form of an insert and connected to the rod 23 via a elastic joint 24.

According to a variant not shown, the core 21, the rod 23 and the socket 22 are made in one piece. The socket 22 provides; a apart, a tight contact with the internal wall of the chamber 11 and delimits, on the other hand, with the core 21 the annular conduit 20

The socket 22 has a flared lower skirt 22a, the internal face, facing the core 21, is provided with a peripheral ring 220. The rod 220 is intended to be in the closed position of the conduit 20 (Figures 1 and 3), in sealed contact with the core 21.

The hollow rod 23 is separated from the core 21 by channels transverse 230 supplied by the exhaust duct 20.

The lateral face of the core 21 and the internal face opposite the bush 22 are parallel and inclined relative to the axis of the pump.

The articulation 24 comprises a central collar 24b mounted by radial tightening around the periphery of the hollow rod 23 above the core 21.

The collar 24b is connected to the sleeve 22 by a spacer 24a elastically deformable allowing the relative displacement of the socket 22 with respect to the core 21.

The socket 22 also includes an upper crown 22b which extends in the extension of the lower skirt 22a; the spacer 24a ensuring the separation between the skirt 22a and the crown 22b.

The upper part of the pump body 1 is closed by snap-fastening of a flange 3, the internal face of which forms the upper stop of the piston 2 and the external face serves as a lower support for the spring 4.

The collar 3 consists of a central sleeve 33 provided an axial bore 30 in which the axial hollow rod 23 moves, integral with the piston 2. The collar 24b has a height substantially equal to that of bore 30, and the respective profiles of the upper edges of the bore and the collar are complementary.

The crown 22b of the sleeve 2 is, in the rest position of the pump shown in FIG. 1, engaged in sealed abutment in a peripheral groove 31 formed on the internal face of the collar 3.

The crown 22b has an internal face slightly inclined towards the axis of the pump while its external lateral face is substantially parallel to this axis.

Likewise, the internal flank 31a of the groove 31, opposite the inner face of the crown 22b, has a slight curvature towards the axis of the pump to ensure sliding contact of the faces in vis-à-vis, one on the other and a guide of the crown 22b in the groove 31 towards the upper stop position.

In this last position, the upper edge of the crown 22b is not in contact with the bottom of the groove 31 so as to avoid any deformation of the sleeve 22. But, the internal face of the crown 22b is in sealed contact with the internal flank 31 of the groove.

Furthermore, the end of the internal flank 31a of the groove 31 is in abutment, with tight contact, against the upper face of the spacer 24. The upper stop of piston 2 therefore corresponds to a double level seal against possible product infiltration which may occur through the vent hole 13, located above the bottom edge of the skirt 22a, in the high stop position of the piston 2.

In the inverted position of the pump, the groove 31 forms a zone of retention allowing to collect the possible flows of product which penetrate inside the chamber 11 via the orifice 13. The central sleeve 33 of the collar 3 is provided with a member 33a watertight latching in the upper part 1 of the body 1 and of a peripheral flange 33b for fixing on the upper edge of the body 1.

The transverse channels 230 open laterally on the rod 23 and opposite the elbow 24c connecting the collar 24b and the spacer 24a of the joint 24.

However, these channels are never blocked by the 24c elbow. due to the presence of remains 240.

The axial hollow rod 23 is connected, outside the metering chamber 11, to a nozzle tube 5, for example, by fitting and locking. Tube 5 carries a shoulder peripheral 51 which delimits an upper bearing face for the spring 4. The shoulder 51 extends downward towards the flange 3, by a cylindrical wall 52 moving in a guided manner with a slight play in the central sleeve 33 which delimits with the wall 52, a housing 54 for the spring 4.

The skirt 22a of the socket 22 has a beveled end with an external face 220a which ensures a tight surface contact of the piston 2 with the internal wall of the metering chamber 11 during its trips.

In FIGS. 2a and 2b, the piston is being lowered in chamber 11 under the effect of a manual push exerted on the tube nozzle 5 via the spray head T.

If the pump is already primed, chamber 11 is filled with product and the thrust is transmitted by the incompressible liquid product to the walls of the chamber 11 and in particular to the skirt 22a of the socket 22 articulated.

However, the socket 22 is the only movable element in the chamber 11.

The thrust exerted on the socket 22 then causes its upward movement along the inner wall of the chamber 11 by elastic deformation of the joint 24 (see FIG. 2b).

This displacement has the result of spreading the peripheral rod 220 from the lateral face of the core 21 and thus open the annular duct evacuation 20.

Continued descent of piston 2 is accompanied by a scraping of the wall of the chamber 11 by the face 220a of the end of the skirt 22a and causes the product to escape through the conduit 20 then successively through the transverse channels 230, the hollow rod 23 and the nozzle tube 5 to the spray nozzle B of the head T.

When the lower edge of the skirt 22a comes into contact with the lower stop delimited by a shoulder 14 in the lower part of the body 1, the entire volume, initially occupied by the product in the chamber 11, has been evacuated, except for the residual volume located in the cavity 15 formed in the lower part of the body 1.

At this stage, the spring 4 is compressed and the wall 52 is pressed in the housing 54 as shown in FIG. 3.

No pushing force is exerted on the bush 22 which then pivots down while being resiliently recalled by the joint 24 which returns to its original shape and position.

The peripheral ring 220 finds its support on the core 21 and thus closes the conduit 20.

The relaxation of the head T and of the nozzle tube 5 is accompanied by the relaxation of the spring 4, of the guided outlet of the wall 52 from the top of the sleeve 33 and the rise of piston 2 in chamber 11 in sucking product into the container through the orifice 10 via the valve 12 in open position.

This phase continues until the piston regains its rest position in high stop where the crown 22b of the sleeve 2 is tightly engaged in the groove 31 of the collar 3 (see figure 1).

Figures 4a and 4b relate to the priming phase of the pump.

Indeed, after the manufacturing, assembly and packaging, the container R contains product but the dosage 11 contains only air.

The first descent of the piston 2 therefore has the effect of compress the air in room 11. From a determined value of overpressure, the sleeve 22 moves in translation upwards and the rod 220 moves away from the core 21 by opening the conduit 20.

The compressed air then escapes to the outside through the conduit 20, the channels 230, the rod 23, the tube 5 and the nozzle B.

All the air present in the chamber 11 is evacuated by opening forced from conduit 20 because the core 21 has a portion tapered lower 21a capable of being housed in the cavity 15 to additional profile located below the level of the bottom stop 14 of the piston 2.

The bottom stop of the piston 2 leaves the duct 20 open for a short time which corresponds to the time necessary for the degassing of the cavity 15.

Then, the relaxation of the head T, the relaxation of the spring 4, the closing the conduit 20 and raising the piston 2 create a vacuum in chamber 11 and ensure its first filling by aspiration of product in the container.

Claims (14)

1. Pump of the type comprising a substantially cylindrical body (1) internally defining a metering chamber (11) of which the lower end (1a) is provided with an intake orifice (10) equipped with a valve (12) and whose upper end is provided, on the one hand, with an outlet orifice and is, on the other hand, closed by a piston (2) capable of moving in said chamber (11), by cooperating with elastic return means (4) outside the chamber (11), between a support up stop and an end-of-stroke down stop, said piston (2) comprising a central core (21) fast with the lower end (23a) of an axial hollow rod (23) whose upper end (23b) projects outside the metering chamber (11) and a coaxial sleeve (22), connected to said rod (23) by an elastic articulation (24) ensuring, on the one hand, a sealed contact with the inner wall of the chamber (11) and defining, on the other hand, with said core (21), an annular evacuating conduit (20) capable of being opened by displacement of said sleeve (22) relatively to the core (21), and the upper part of the pump body (1) being closed by a flange (3) of which the inner face, on the one hand, forms the up stop of the piston (2) and the outer face, on the other hand, serves as bottom support for the return means (4); said flange (3) being provided with an axial bore (30) in which the hollow rod (23) fast with the piston moves, characterized in that said sleeve (22) comprises an upper ring (22b) intended to come into sealed engagement in a peripheral groove (31) made on the inner face of said flange (3).
2. Pump according to Claim 1, characterized in that said sleeve (22) comprises a flared lower skirt (22a) whose inner face opposite the core (21) is provided with a peripheral snap ring (220) intended, when the evacuating conduit (20) is in position of closure, to be in sealed contact with said core (21).
3. Pump according to one of Claims 1 or 2, characterized in that said articulation (24) comprises a central collar (24b) mounted by radial clamping on the periphery of said axial hollow rod (23) and connected to the sleeve (22) by an elastically deformable distance piece (24a).
4. Pump according to one of the preceding Claims, characterized in that the flange (3) is constituted by a central bush (33) provided with a snapping member (33a) in the upper part of the body (1) and a peripheral flange (33b) for fixation on the upper raised edge of said body (1).
5. Pump according to one of the preceding Claims, characterized in that said hollow rod (23) and said core (21) are made in one piece.
6. Pump according to one of the preceding Claims, characterized in that said hollow rod (23) is separated from the core (21) by transverse channels (230) supplied via the evacuating conduit (20).
7. Pump according to one of the preceding Claims, characterized in that said axial hollow rod (23) is connected, outside the metering chamber (11), to a spray nozzle tube (5).
8. Pump according to Claim 7, characterized in that the spray nozzle tube (5) bears a peripheral shoulder (51) defining an upper support face for the return means (4) of the piston (2).
9. Pump according to Claims 4 and 8, characterized in that said shoulder (51) extends downwardly by a cylindrical wall (52) moving in guided manner in said central bush (33) of the flange (3) which defines with said wall (52) a housing (54) for said return means (4).
10. Pump according to one of the preceding Claims, characterized in that the body (1) comprises an orifice (13) forming vent located, when the piston (2) is in up position, above the lower edge of the sleeve (22).
11. Pump according to one of the preceding Claims, characterized in that said sleeve (22) presents a bevelled end (220a) ensuring a sealed scraping surface contact with the inner wall of the metering chamber (11).
12. Pump according to one of the preceding Claims, characterized in that the lateral face of the core (21) and the opposite inner face of the sleeve (22) are parallel and inclined with respect to the axis of the pump.
13. Pump according to one of the preceding Claims, characterized in that said core (21) presents a truncated lower part (21a) capable of being housed in a cavity (15) of complementary profile made in the lower part (1a) of the body (1) under the level of the down stop of the piston (2) to allow a forced opening of the evacuating conduit (20) at priming.
14. Pump according to Claims 3 and 6, characterized in that the distance piece (24a) of the articulation of the sleeve (22) is disposed substantially opposite the opening of the transverse channels (230) and comprises drafts (240).

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