FR2641337A2 - Pump with precompression for spraying a liquid - Google Patents

Abstract

Improvement to the arrangements such as defined in any one of the claims of the main patent. According to the addition, the precompression pipe 6 is connected to at least two separate compression chambers 5a, 5b, respectively connected to two separate reservoirs of liquids 42a, 42b, each compression chamber including a closure valve 14a, 14b blocking or freeing an orifice 13a, 13b for drawing off a liquid 45a, 45b from a reservoir and a driving piston 11a, 11b for transferring this liquid to the precompression pipe through an intermediate transfer chamber 8a, 8b, the liquids coming from the two reservoirs under the effect of the simultaneous control of the two driving pistons being mixed in the precompression pipe before leaving through the discharge orifice 25 towards the spray head 26.

Description

First certificate of addition to main application No. 88.10047 of July 26, 1988
PRE-PRESSURE PUMP FOR DIFFUSION OF A LIQUID
LIQUID
The main patent relates to a precompression pump for the diffusion of a liquid, comprising an orifice for withdrawing this liquid from a reservoir bottle, closable by a closure valve, an orifice for expelling the liquid towards a head. diffusion and a support shell in which a first internal compression chamber is produced, a driving piston cooperating with the first chamber for the transfer of the liquid between the withdrawal orifice and the expulsion orifice, characterized in that it further comprises a second intermediate transfer chamber between the first chamber and the expulsion orifice and a precompression duct formed in the support shell in a cooperating situation with precompression means mounted in this shell, the first chamber being parallel and not coaxial with the precompression duct.

 Such a pump structure is more particularly intended to be mounted on a case or canister for spraying a liquid product in the form of an aerosol, by eliminating the use of a propellant gas previously enclosed under pressure inside this case, in order to project the liquid through a nozzle or the like mounted in the diffusion head, this by means which carry out a prior compression of the liquid doses to be delivered, taken from the reservoir bottle by the effect of the engine piston.

 It defines in particular a precompression pump arranged so that the diffusion head is fixed relative to the case and in particular independent of the movement of the driving piston withdrawing the liquid from the tank, which improves the conditions under which the projection of the liquid aerosol, in particular by making it possible to target more precisely the zone to be reached by it. It also allows the distribution of predetermined unit doses, of constant volume, this regardless of the position of the pump, even when the case is turned over to be used upside down, which is not possible when the cabinet is provided to provide a pressurized propellant aerosol.

 The advantages of the precompression pump thus arranged are in particular obtained thanks to the provision in the pump, between the first chamber where the compression of the withdrawn liquid takes place, coming from the reservoir bottle through the sampling orifice, of an intermediate chamber transfer, arranged transversely in the case through the support shell, so that the liquid dose taken by the driving piston and brought into the compression chamber is discharged into a separate precompression assembly, the pump thus ensuring total separation withdrawal and precompression functions of the liquid before expulsion thereof by the nozzle of the diffusion head.

 The present addition relates to improvements made to a pump of the kind recalled above, as claimed with the main patent, making it possible in particular to carry out with the same assembly the in situ mixing of two or more liquid products. generally different, or of a liquid and an appropriate amount of air to produce an emulsion thereof, again without having to use a pressurized gas for the propulsion of these products at the time of their projection common by the nozzle of the diffusion head.

 The improvements envisaged in particular make it possible, in addition to the advantages specific to the structure of the pump according to the main patent, to avoid the drawbacks of known systems where the mixing of the products is carried out by placing in an external case containing a first liquid, a second internal container or container containing the other liquid, each container being provided with a valve, the valve of the internal container being joined to that of the external container by a shell delimiting an enclosed space where the mixing takes place before leaving the emulsion of these two products by the valve of the outside boot maker, under the effect of a propellant gas enclosed in the two boot makers with the corresponding liquids.

 In particular, with this type of known system, the shell necessarily contains, after each spraying, a residual volume of the mixture of the two liquids which can freeze or solidify more or less completely, limiting, or even preventing, subsequent spraying, and in any case by modifying the texture of the mixture at the start of each new use.

 In addition, these conventional systems are necessarily designed to operate in continuous diffusion, as long as the user exerts pressure on the valve releasing the outlet of the mixture under the effect of the propellant gas and therefore does not make it possible to provide precise doses but limited, exactly determined. Finally, they are complex to produce and consequently represent a non-negligible cost, independently of that of the liquid products themselves.

 According to the present addition, the precompression pump considered is characterized in that the precompression duct is joined to at least two separate compression chambers, connected respectively to two separate liquid tanks, each compression chamber comprising a shut-off valve or releasing a liquid withdrawal port from a reservoir and a working piston for the transfer of this liquid to the precompression conduit through an intermediate transfer chamber, the liquids coming from the two reservoirs by effect of the simultaneous control of the two engine pistons mixing in the precompression duct before leaving through the expulsion orifice towards the diffusion head.

 Preferably, the precompression pump is associated with two reservoirs each comprising a different liquid to be mixed in the precompression chamber where these liquids are introduced by independent inlets from the compression chambers, themselves combined respectively with each of the reservoirs.

 Of course, it goes without saying that the term liquid thus used, in itself covers a wide range of products, whatever their densities or their relative fluidities, these products possibly being pasty, appearing in the form of foam or in any other form suitable for each use.

 Thus and in an alternative embodiment, one of the two tanks can be omitted, the mixing of the liquid coming from the other tank being carried out with air pressurized in the first compression chamber.

 The provisions envisaged in accordance with this addition lead to the same advantages as those listed in the main patent, in particular by avoiding the use of any propellant gas, in particular based on chlorofluorinated products or even more containing a hydrocarbon whose regulations in force or to come already prohibit or are likely to prohibit use soon, especially for household applications with wide circulation, because of the risks for the environment and the dangers of flammability or explosion.

 The precompression pump also proposes to deliver precise doses of the mixture produced, the ratio corresponding to this mixture being able to vary on demand either according to the stroke of the engine pistons in the compression chambers or according to the respective diameter of these chambers.

 According to an advantageous characteristic of the present addition, the liquid reservoirs are constituted by deformable pockets, produced in any shape or with any suitable material.

 These pockets can thus be made of plastic, or a composite product, combining a metal with plastic, or even metal only, of the type of deformable tubes used to contain toothpaste or other product of the same consistency. These pockets are preferably screwed or snapped onto the end of the precompression chambers in line with the sampling orifices of these chambers, prior to their filling with liquid products, which makes it possible to envisage, after complete use of the liquids contained in these pockets, replace them with others, keeping the pump proper. Alternatively however, the pockets may be welded or otherwise immobilized on the compression chambers.

 The bags are filled with the liquids to be mixed easily, the boxes being placed upside down and having a removable bottom previously removed. The pockets are mounted on the compression chambers, their opposite ends being open for the placement of liquids poured into these pockets. Once the filling is completed, these ends are closed, by crimping or the like, the flexibility of the material of the pockets allowing this operation without particular difficulties. As the liquid doses are taken from the bags, they gradually deform by pushing the products they contain towards the compression chambers, until their complete exhaustion.

 Other characteristics of a precompression pump provided with improvements according to the present addition will become apparent from the following description of several exemplary embodiments, given by way of non-limiting example, with reference to the appended drawings in which - Figure l is an axial sectional view of a precompression pump as provided in the main patent, but adapted to the homogeneous mixture of two separate liquid products; - Figure 2 is a cross-sectional view along line II-II of Figure 1; - Figures 3 and 4 are detailed perspective views of components used in the production of the precompression pump considered; - Figure 5 is a top view of the pump according to Figure 1; - Figure 6 is a partial side view of the upper end of the pump of Figure 1 ;; - Figure 7 is a view of the lower end of the pump casing, containing the reservoirs of the two liquids, the housing being shown upside down, before these reservoirs are filled; - Figure 8 is an axial sectional view of an alternative embodiment of Figure 1, more particularly suitable for mixing a liquid and air for the emulsion of this liquid.

 We have used in these figures - reference numbers identical to those used in the main patent, to identify the same elements of the pump, also designated under the same terms.

 In Figure 1, the reference 1 thus designates the bottle or external casing 1 provided at its upper end in accordance with the invention, with a precompression pump whose operating principles are identical to those envisaged in the main patent, the pump being however provided here with improvements according to the present addition.

 The shell 1 internally comprises a support shell 2, comprising in its central part a tubular extension 4 inside which a precompression duct 6 is arranged.

This comprises at its upper part an expulsion orifice 25, closed by a needle piston 23, normally applied against the orifice 25 under the effect of a spring 24. Channels 31 are arranged on either side of the conduit 6 in a piece forming a nozzle 22, mounted in the extension 4.

A groove 34 connects the channels 31 with spaces 35a, 35b formed between vertical grooves of the part 22. A nozzle 27 is provided on the diffusion head 26, connected to the expulsion orifice 25. The upper part of the case 1 is covered by a protective cap 30, which is advantageously snapped onto the case and has a lateral opening 29, so as to leave room for a movable pusher 10. Preferably, this comprises a central part 40 slightly in hollow and a hollowed-out central part 41, allowing the passage of the head 26 when the pusher is pushed in (see also
Figure 6).

 In accordance with the provisions of this addition, the envisaged assembly is designed to ensure the sampling, compression and mixing of two different liquid products, brought simultaneously into the precompression duct, before expulsion by the nozzle of the diffusion head, thanks mounting two separate sub-assemblies inside the same housing, separately removing these liquids and then transferring them simultaneously to the conduit and the head.

 In the drawing, the parts of the pump which allow the withdrawal and transfer of the two liquids are designated under the same references, each of them being assigned indices respectively a and k depending on whether it is one or the other of these liquids and the organs that concern them.

 As can be seen in Figures 1 and 2 in particular, the shell 2 thus supports two compression chambers 5a, 5b, each of them comprising a driving piston 11a, 11b actuated simultaneously by the pusher 10 against a spring 28a, 28b.

 In each chamber 5a, 5b, there is provided opposite the piston, a sampling orifice 13a, 13b, normally closed by a ball 14a, 14b, forming a valve. Each compression chamber is also joined by a lateral passage 16a, 16b, to a transfer chamber 8a, 8b, communicating with the precompression duct 6 through the groove 34 and the spaces 35a, 35b. The chambers 8a, 8b, each have a ball valve 18a, 18b, and a spring 19a, 19b, suitable for applying the ball against the passage 16a, 16b, to close '-normally celuici.

The sampling orifices 13a and 13b are joined in parallel to two reservoirs 42a and 42b, housed one next to the other in the housing 1,
Each reservoir has an end flange 43a, 43b, here screwed against an end piece 44a, 44b, provided in a holding part 7, fixed under the shell 2 (see Figure 3). Of course, each reservoir 42 could be mounted under the part 7 in line with the orifices 13 and the associated valve 14 by other means, removable or not, for example by snap-fastening or by welding or crimping.

 Each reservoir 42 contains a liquid product 45a, 45b respectively, and is normally closed at its lower end 46a, 46b, by crimping, knurling or other similar means.

 Figure 7 shows the housing 1 and the tanks 42a and 42b which it contains, prior to their filling with liquids 45a, 45b, the case being shown upside down. Once this filling has been carried out, the ends 46a and 46b are folded back and crimped to ensure the watertight closing of these tanks, the casing then being able to be closed by fitting an end cover 47, comprising a lateral flange 48, coming from force to engage in a laminator 49 at the end of the shoemaker. A vent 50 is usually provided in the center of the cover 47.

 Advantageously, the reservoirs 42a and 42b are constituted by pockets of plastic material, metal-plastic composite, or of metal, of the toothpaste or other tube type, of substantially conical shape, allowing progressive crushing of the pockets as and when from the evacuation of the liquids which they contain towards the compression chambers 5a and 5b, until complete emptying of these bags which can then be replaced by others suitably filled according to the process indicated.

 The operation of the precompression pump thus produced is easily deduced from the indications given above, with reference to the details provided in the main patent.

 The tanks 42a and 42b being previously fixed on the ends of the compression chambers 5a and 5b and filled with their respective liquids 45a and 45b according to the process indicated, the device is ready to be used, each actuation of the movable piston 10, ensuring the taking of a dose of these liquids in each of the compression chambers, causes the liquid already present in these chambers to be sent beforehand to the precompression duct, in a manner exactly specified in the main patent. The two liquids received in the conduit 6 are intimately mixed with the passage of the expulsion orifice 25 and expelled together by the nozzle 27 of the head 26.

 At each stroke of the pistons 11a, 11b, the chambers 5a, 5b, take a new dose, exactly determined, at the same time as the precompression duct 6 receives equivalent doses, closely mixed and delivered in a precise manner and always identical to it. even at each push-button 10 command.

 FIG. 8 illustrates another alternative embodiment where one of the compression chambers, for example the chamber 5a, is not here associated with a flexible tank 42, but opens directly into the internal atmosphere of the shoemaker 1, the open air through the vent 50 formed in the cover 47.

In this variant, the liquid 45b taken from the bag 42b is compressed in the chamber 5b and discharged into the precompression duct 6. In the latter, it is mixed with air coming from the chamber 5a, the emulsion thus produced then being delivered by the expulsion orifice 25 in the diffusion head 26. Preferably, this comprises a mixing screw 51, provided with a helical thread 52, this screw being mounted for rotation in a bore 5.3 of the head 26, to effect the desired mixing of the liquid and the air before leaving through the nozzle 27.

 Whatever the variant adopted, a precompression pump is thus produced capable of providing a homogeneous and constant mixture of two liquid or pasty products, possibly of an emulsion of a liquid in the form of an aerated foam which is intimately brewed, but always without the addition of gas previously enclosed under pressure in the housing.

This is usually made of aluminum or other light metal; depending on the case, however, due to the absence of propellant under pressure and as a result of dielectric couples with the liquids of the reservoirs possibly creating damaging corrosion points, it is possible to envisage making the bootmakers in different materials, in particular with materials suitable plastics.

 The device is simple, inexpensive and very easy to use, with increased possibilities of reuse by simple change of pockets containing the liquids without having to replace the pump itself. The doses supplied can be exactly determined with a ratio which depends only on the stroke of the driving piston or on the diameter of the compression chambers, defined by construction.

 Finally, the application of the device to all kinds of products according to the desired conditions of use is easy and does not require any adaptation capable of modifying the overall structure of the device.

Claims (6)

 1. Improvement to the provisions as defined in any one of the claims of the main patent, characterized in that the precompression duct (6) is joined to at least two separate compression chambers (5a, 5b), connected respectively to two separate liquid tanks (42a, 42b), each compression chamber comprising a closing valve (14a, 14b) closing or releasing a withdrawal orifice (13a, 13b) of a liquid (45a, 45b) from a reservoir and a working piston (lia, llb) for the transfer of this liquid to the precompression duct through an intermediate transfer chamber (8a, 8b), the liquids coming from the two tanks by effect of the simultaneous control of the two working pistons mixing in the precompression pipe before exit through the expulsion orifice (25) towards the diffusion head (26).  2. Improvement according to claim 1, characterized in that the precompression pump is associated with two reservoirs (42a, 42b) each comprising a different liquid (45a, 45b).  3. Improvement according to claim 1, characterized in that one of the tanks is deleted, the corresponding compression chamber (5a) communicating directly with the outside air to form with the liquid (45b) of the second tank (42b) a emulsion in the precompression pipe (6).  4. Improvement according to claim 3, characterized in that the precompression duct (6) comprises beyond the expulsion orifice (25) a screw (51) with helical thread (52), mounted for rotation in a bore (53) of the diffusion head (26) in order to produce the emulsion of air and liquid.  5. Improvement according to any one of claims 1 to 4, characterized in that the liquid tanks (42a, 42b) are constituted by flexible bags, of plastic material, metal-plastic composite, or of metal, suitable for deform as the liquids (45a, 45b) are taken from these pockets.  6. Improvement according to claim 5, characterized in that the flexible pockets (42a, 42b) are screwed or snapped, or welded or otherwise fixed, at the end of the compression chambers (5a, 5b), in line with the orifices sampling (13a, 13b).