EP0974401A1 - Pump with venting means - Google Patents

Abstract

The air filling pump for a container has a casing (18) with a vent selectively opened and closed by a vertically moving pusher. The latter has an internal skirt (12) which slidingly engages the pump interior to seal it when in its upper and lower positions.

Description

The present invention relates to a pump intended to be mounted on a container for taking and dispensing a dose of product therein, and more in particular a pump of the return air type, that is to say which allows an air return in the container to compensate for the amount of product taken up by the pump.

We know from US Patent 3,759,426 a pump intended to be mounted on a container, comprising a movable pusher between a high position and a low position relative to a pump body and defining therewith a pumping chamber of variable volume, the pump body comprising a vent capable of communicating by a passage with the outside of the container when the pusher is in an intermediate position between its high and low positions, so as to allow air to enter the container during the aspiration of the product in the pumping chamber.

The pusher has an outer skirt suitable for isolating the vent when the pusher is in its high and low positions. The pusher has an inner skirt which defines with the outer skirt a groove for accommodating a return spring.

The outer skirt is exposed to possible dirt which is likely to come into contact with the product contained in the pump body.

In addition, the return spring plunges into the product, which can cause compatibility issues.

The subject of the invention is a new return air pump which, while being inexpensive construction and reliable operation guarantee good conditions of conservation of the product in the container.

The pump according to the invention is of the type comprising a movable plunger between a high position and a low position relative to a pump body, defining with the latter a pumping chamber of variable volume, the pump body comprising a vent capable of communicating by a passage with the outside of the container when the pusher is in an intermediate position between its high and low positions, so that allow air to enter the container when the product is drawn into the chamber pumping and is characterized in that the pusher has an inner skirt made in one piece and able to slide tightly inside the body of pump, this inner skirt being shaped to isolate said vent from the outside when the pusher is in its high and low positions.

Thus, in the invention, the interior of the container does not communicate with outside except when the pusher is in an intermediate position between its positions high or low, i.e. at the time of use.

The product contained in the container therefore remains isolated from the outside when the pusher is in the low transport position or in the high position awaiting use.

This avoids for example that solvents or perfumes contained in the product inside the container does not leave it in case of long period of non-use of the pump through the passage used for air intake.

The inner skirt of the pusher, by its positioning inside the pusher, is not subject to any dirt which could interfere with the pump operation or contaminate the product inside the container.

In a particular embodiment, the aforementioned inner skirt is applied so sealed by its lower part on the pump body and the distance separating the vent from said lower part when the pusher is in its lower position is less than or equal, preferably substantially equal to the displacement stroke of the pusher from its position low to its high position, so that said lower part isolates the vent from the outside when the pusher is in its high position.

Advantageously, the inner skirt is applied in a sealed manner by its part upper on the upper end of the pump body when the plunger is in position low.

In a preferred embodiment, the inner skirt has, between its parts lower and upper, a constriction providing an annular space inside the body of pump, space into which the aforementioned vent opens when the pusher is in its position low or in an intermediate position between its high and low positions.

In a particular embodiment, the pump body is connected to its upper end by an annular bearing to a mounting skirt subject to a neck of the container.

This mounting skirt is advantageously extended upward by a cylindrical wall defining a guide for a helical spring working in compression to recall the pusher in the high position.

Preferably, the pusher comprises a discharge valve comprising a ball forming a shutter.

This ball is retained in a housing of the pusher by means of retained advantageously made integrally with it by molding in material plastic.

Preferably, the aforementioned housing is located in a conduit and said means retainers are formed by the lower end of this duct, which is shaped to allow the introduction of the ball by elastic deformation.

The pump body advantageously includes a suction valve comprising a ball forming a shutter and the lower end of the aforementioned conduit is arranged to hold the ball of the suction valve in the closed position when the pusher is in its low position.

• la figure 1 est une vue schématique en coupe axiale d'une pompe conforme à un exemple de réalisation de l'invention,
• la figure 2 représente isolément le poussoir de la pompe représentée sur la figure 1,
• la figure 3 représente isolément la partie fixe de la pompe représentée sur la figure 1,
• la figure 4 représente un détail de réalisation du poussoir, et
• les figures 5 et 6 représentent le poussoir dans une position intermédiaire et dans sa position haute respectivement.

Other characteristics and advantages of the present invention will emerge on reading the detailed description which follows, of an example of non-limiting implementation, and on examining the appended drawing in which:

• FIG. 1 is a schematic view in axial section of a pump according to an exemplary embodiment of the invention,
• FIG. 2 represents the pusher of the pump shown in FIG. 1 in isolation,
• FIG. 3 represents in isolation the fixed part of the pump shown in FIG. 1,
• FIG. 4 shows a detail of the embodiment of the pusher, and
• Figures 5 and 6 show the pusher in an intermediate position and in its upper position respectively.

The pump 1 shown in Figure 1 includes a movable pusher 2 which can move vertically along an axis X relative to a fixed part 3, which comprises a mounting skirt 4 secured to the neck 5 of a conventional container 6 and partially represented.

In the example of embodiment described, the mounting skirt 4 is screwed onto the neck 5 but alternatively it could be fixed otherwise on the latter, by snap-fastening example.

The mounting skirt 4 is extended upwards by a cylindrical wall defining a guide 7 for a helical spring 8 of axis X working in compression and also serving as a guide for pusher 2.

The guide 7 has at its upper end an annular flange 47 which limits the travel in movement upwards of push-button 2.

The spring 8 rests at its lower end against an annular bearing 9 of the fixed part 3.

This scope 9 extends radially inwards from the region in which the mounting skirt 4 and the guide 7 meet.

The spring 8 comes to bear at its upper end in the bottom 10 of a annular groove 11 of pusher 2.

Spring 8 is not exposed to the product, unlike the spring used in the pump described in the aforementioned US patent 3,759,426. So there is no problem of accounting between the material used to make the spring and the product contained in the container.

This groove 11 is formed between an inner skirt 12 symmetrical with revolution around the X axis and a coaxial outer skirt 13.

Locking means are provided on the facing faces of the skirt 13 and the mounting skirt 4 to allow the pusher 2 to be blocked in its low position shown in Figure 1.

This blocking is useful during the transport of the container 6 for example, in order avoid accidental product leakage.

The abovementioned locking means comprise, in the exemplary embodiment described, lugs 14 formed on the radially outer surface of the mounting skirt 4 and reliefs 15 located on the radially inner surface of the outer skirt 13.

These pins 14 and reliefs 15 can cooperate in the manner of a type of attachment. bayonet.

To block push-button 2 in the low position, the user presses it while the reliefs 15 are angularly offset relative to the pins 14, to bring the first at a level lower than the second, then rotate the pusher 2 around the X axis so as to position the reliefs 15 under the lugs 14.

When the user releases the pusher 2, the lugs 14 prevent the latter to go back under the action of spring 8.

To unlock pusher 2, the user presses it lightly then rotates it so as to release the reliefs 15.

When the pusher 2 is in the high position, the outer skirt 13 comes in support, by reliefs 48 produced above the abovementioned reliefs 15, on the annular rim 47 of guide 7, as can be seen in FIG. 6.

A central duct 16 is made in one piece by molding of material plastic with inner skirt 12.

This conduit 16 is centered on the X axis and is connected at its upper end to a lateral duct 17, also made in one piece by plastic molding with the rest of pusher 2.

The lateral conduit 17 opens to the outside of the pusher 2 through an orifice outlet 40, which is oriented in a direction Y perpendicular to the axis X.

The aforementioned annular bearing 9 is connected to the upper end of a body of tubular pump 18, closed at its lower end by a bottom 19.

The bottom 19 serves as a seat for a ball 20 and includes a nozzle 42 intended for the connection of a dip tube 21 extending to the bottom of the container 6 where it opens.

The ball 20 constitutes with its seat made on the bottom 19 a valve suction as will be explained below.

The lower end of the central duct 16 defines, as can be seen in FIG. 4, a housing 35 in which a ball 22 is retained.

The ball 22 constitutes with its seat produced inside the housing 35 a discharge valve, as will be specified below.

The lower part 23 of the inner skirt 12 is arranged to slide from sealingly in contact with a cylindrical portion of revolution of the interior surface of the pump body 18.

The upper part 24 of the inner skirt 12 is arranged to be applied from sealingly on the upper end of the pump body 18 when the pusher 2 is in the low position, as shown in Figure 1.

More specifically, the upper part 24 is shaped to be inserted with friction in the pump body 18 when the pusher 2 is in the low position.

The inner skirt 12 has a constriction 46 between its lower parts 23 and upper 24.

This constriction 46 defines with the pump body 18 an annular space 25 of which the function will be specified below.

A vent 26 opening at the base of the neck 5 is produced in the pump body 18 for communicating the abovementioned annular space 25 with the interior of the container.

The pump body 18 is applied sealingly at its end on the inside surface of the neck 5.

We will now describe more precisely with reference to Figure 4 the lower end of the central duct 16, which houses the ball 22.

This duct 16 is internally shouldered at 30 and its internal diameter passes, while this shoulder is crossed by moving downward in the housing 35, from a value d ₁ less than the diameter of the ball 22 to a value d ₂ slightly greater than the diameter thereof.

The internal diameter of the duct 16 is then progressively reduced downwards along a conical surface 31 until a value d _{3 is} slightly lower than the diameter of the ball 22.

The conical surface 31 serves as a seat for the ball 22 and the cylindrical surface of diameter d ₂ extends above this surface 31 along the axis X over a height sufficient to allow the ball 22 to move away from its seat during product distribution in order to obtain the desired flow rate.

The central duct 16 ends at its lower end with lugs 32 directed radially inwards and shaped so as to be able to deform elastically radially outward when the ball 22 is introduced from below in housing 35 according to arrow F.

Recesses 33 are made on the outside of the tabs 32 at the level of their junction with the rest of the conduit 16 so as to give them the flexibility required for mounting the ball 22.

Reliefs 36 are made in the upper part of the housing 35 to prevent that the ball 22 does not close the central duct 16 during the distribution of the product.

FIG. 3 shows the fixed part 3 of the pump in isolation.

As can be seen in this figure, the bottom 19 has a recess conical 37 centered on the X axis and converging downwards, intended to serve as a seat for the ball 20.

Legs 38 extend upward this recess 37 so as to constitute a cage 45 in which the ball 20 is retained, with a possibility of deviating from its seat 37 when the product is taken from the container.

These legs 38 are four in number in the example described and have each a tooth 39 projecting radially inward.

These teeth 39 are bevelled so as to facilitate the introduction of the ball 20 from above in the cage 45.

The legs 38 deform elastically radially outward to allow the teeth 39 to be crossed by the ball 20 when it is placed in the cage 45.

The bottom of the recess 37 communicates by a bore 41 with the inside of the end piece 42, in which the plunger tube 21 is force fitted, as shown in Figure 1.

Note that when the pusher 2 is in its low position shown on Figure 1, the legs 32 of the central duct 16 come to bear while undergoing a slight elastic deformation against the ball 20, so as to keep the latter pressed against its seat 37.

The end piece 42 is thus closed and a product rise in the product is avoided. pump, which reduces the risk of accidental product leakage during transport of the container.

The annular space delimited by the pump body 18 and the internal skirt 12, around the central duct 16, constitutes a pumping chamber 43 whose volume varies when the pusher 2 moves axially on the axis X.

The operation of pump 1 is as follows.

Once the push-button 2 is unlocked as explained above, the latter goes back under the return action of the spring 8 until it takes the high position shown in FIG. 6, passing through the intermediate position shown in FIG. 5.

During the upward movement of pusher 2, the volume of the pumping 43 increases, causing a depression therein, raising the ball 20 of the suction valve and the product suction in the bottom of the container 6 by the dip tube 21.

The ball 22 of the discharge valve is then pressed against its seat 31 and isolates the central duct 16.

The removal of product from container 6 causes a vacuum in this latest.

In the example of embodiment described, an air intake is allowed in the container 6 during the movement of raising the pusher 2 thanks to the fact that the vent 26 communicates with the outside of the container via the annular space 25.

The path traveled by the air has been illustrated in FIG. 5 by an arrow A entering the container 6 when raising the pusher 2.

The air first passes between the mounting skirt 4 and the outer skirt 13 of the pusher 2, then gains vent 26 along the annular space 25.

It will be noted that the entry of air into the container 6 is made possible by the the upper part 24 of the inner skirt 12 has ceased to apply so waterproof on the pump body 18.

When the pusher 2 reaches its high position shown in FIG. 6, the lower part 23 of the inner skirt 12 is positioned opposite the vent 26 for shut it off.

To this end, the upward stroke of the pusher is substantially equal to the distance 1 separating the vent 26 from the lower part 23 of the inner skirt 12 when the pusher is in the low position.

Thus, the interior of the container 6 again ceases to communicate the exterior for a good conservation of the product contained in the container 6.

In other words, we can leave the pusher 2 in the high position without fear of degradation of the product by the outside air thanks to the fact that the passage through which the vent 26 communicates with the outside is closed by the lower part 23 of the inner skirt 12.

When the user presses push-button 2, the volume of the pumping 43 decreases, which causes compression of the product therein.

The ball 20 of the suction valve is then pressed against its seat 37, preventing a return of the product in the container 6, while the ball 22 of the valve distribution lifts under the effect of the pressure of the product and allows it to flow by the central duct 16 then by the lateral duct 17 to reach the dispensing orifice 40.

Thanks to the invention, there is a pump having few constituent elements, namely in the example described a pusher 2 and a fixed part 3 each made at with the exception of the two balls and the spring, in one piece by molding respectively in polyethylene and polypropylene in particular, inexpensive to manufacture and reliable operation.

The risk of product leakage during container transport is reduced by by blocking the ball of the suction valve.

Finally, the pump allows the product to be stored away from outside air even when the pusher is left in the high position for a long time.

Of course, the invention is not limited to the embodiment which comes to be described.

One can in particular make various modifications to the pump, for example as to how to fix the fixed part 3 to the container 6.

Claims (10)

Pump intended to be mounted on a container (6), comprising a movable pusher between a high position and a low position relative to a body of pump and defining with it a pumping chamber of variable volume, the pump body (18) comprising a vent (26) capable of communicating through a passage (25) with the outside of the container (6) when the pusher (2) is in an intermediate position between its high and low positions, so as to allow air to enter the container (6) during the aspiration of the product into the pumping chamber (43), characterized by the fact that the pusher has an inner skirt (12) made in one piece and capable of slide tightly inside the pump body (18), this inner skirt being shaped to isolate said vent from the outside when the pusher is in its positions high and low. Pump according to claim 1, characterized in that said inner skirt (12) is applied in leaktight manner to the pump body (18) through its lower part (23) and by the fact that the distance (1) separating the vent (26) from said lower part (23) when the pusher is in its lower position is less than or equal, preferably substantially equal to the displacement stroke of the pusher (2) from its low position to its position high, so that said lower part isolates said vent from the outside when the pusher is in the high position. Pump according to claims 1 and 2, characterized in that said skirt inner (12) is applied in a sealed manner by its upper part (24) to the end upper part of the pump body (18) when the plunger (2) is in the lower position. Pump according to one of claims 2 and 3, characterized in that the skirt inner (12) has, between its lower (23) and upper (24) parts, a constriction (46) providing an annular space (25) inside the pump body (18), space in which opens said vent (26) when the pusher (2) is in its low position or in an intermediate position between its high and low positions. Pump according to any one of the preceding claims, characterized by the fact that the pump body (18) is connected at its upper end by a bearing annular (9) to a mounting skirt (4) secured to a neck (5) of the container (6). Pump according to the preceding claim, characterized in that the skirt of mounting (4) is extended upwards by a cylindrical wall defining a guide (7) for a helical spring (8) working in compression to recall the pusher (2) in high position. Pump according to any one of the preceding claims, characterized by the fact that the pumping chamber (43) communicates with a dispensing orifice (40) by means of a discharge valve comprising a ball (22) forming a shutter retained in a housing (35) of the pusher, this discharge valve opening during the distribution of the product contained in the pumping chamber and closing during the filling the latter, the pusher further comprising means for retaining the ball made in one piece with said housing (35) by plastic molding. Pump according to claim 7, characterized in that said housing (35) is located in a conduit (16) and by the fact that said retaining means are constituted by the lower end of this conduit, which is shaped to allow the implementation place of the ball (22) in said housing (35) by elastic deformation. Pump according to claim 8, characterized in that it comprises a suction valve comprising a ball (20) forming a shutter, this valve opening during the suction of the product in the pumping chamber (43) and closing during the distribution of the product contained in the latter, the lower end of said conduit (16) being arranged so as to keep the ball of the suction valve in the position of closing when the pusher (2) is in its low position. Pump according to any one of the preceding claims, characterized by the fact that the pusher comprises a helical spring bearing at its end upper in the bottom of the groove formed between the inner skirt (12) and a skirt outer (13) coaxial.

Images