FR2674774A1 - DEVICE FOR SPRAYING A LIQUID COMPRISING A PRESSURIZED CONTAINER PROVIDED WITH AN ADDITIONAL GAS VALVE VALVE. - Google Patents

Abstract

According to the invention, the additional gas is taken through a sintered element (13) having dimensions and a porosity such that the flow rate under 10 x 105 pascals is between 10 and 50 cm3 / s.

Description

DEVICE FOR SPRAYING A LIQUID COMPRISING

  A PRESSURIZED CONTAINER WITH A TAP VALVE

ADDITIONAL GAS.

  The present invention relates to a device for spraying a liquid, comprising a container

  pressurized with an additional gas valve

  nelle. We know aerosol type spraying devices which consist of a container containing a product in liquid form to be sprayed and a propellant. The propellant is, in known manner, a liquefied gas such as chlorofluorinated hydrocarbons, propane or butane, or a compressed gas, for example compressed air The container is provided with a valve for the outlet of the pressurized liquid This valve is fixed on a valve cup, so that the fixed valve body opens in the container and that the mobile element opens outside the container, the opening of the valve being effected by translation or insertion of the mobile element in the valve body The insertion of the mobile element of the valve is usually obtained using a push button, which can

  to press on the moving element of the valve, button-

  push button that the user can move in transla-

  manually to activate the valve The button-

  pusher generally comprises an ejection channel of the

  product to be dispensed and a spray orifice.

  When the spraying of the product must be carried out "head up", that is to say the valve and the push-button being arranged above the pressurized container, a dip tube is generally fixed to the valve body, this tube plunger to supply the valve body with liquid to

  spray even when the liquid level is low

  corn. It is known to provide an additional gas intake at the valve body, which makes it possible to take a fraction of the gas under pressure contained in the container above the liquid and, consequently, to facilitate the ejection of the liquid to be sprayed. and to promote the spraying of said liquid. When the propellant is a compressed gas

  not liquefied, e.g. compressed air, press-

  The pressure in the container is generally limited to about 12 x 105 pascals The pressure in the

  container decreases as it is dispensed

  tion; it follows that at the end of dispensing and in the absence of additional gas intake, the spraying is generally not satisfactory because the pressure is insufficient to spray adequately by mechanical effect at the dispensing orifice. since the initial pressure is capped To improve the spraying, we have

  therefore tried to provide the valve with an addi-

  tional; but with the additional gas intakes used so far, which have a diameter of about 0.3 to 0.4 mm, the container is, after a few sprays, completely emptied of the compressed gas which it initially contains. tried to use additional gas intakes of smaller diameter: but it is mechanically impossible

  to make, industrially, holes or openings

  tures having a diameter of less than about 100 to 150 micrometers and, with an additional gas intake of this diameter, the pressure in the container decreases

still too quickly.

  According to the present invention, it has been found that it is possible to improve the spraying by a non-liquefied compressed gas, without emptying the pressurized container too quickly from its propellant gas, by introducing into the additional gas intake a

sintered or sintered element.

  The present invention therefore relates to a spraying device comprising a container pressurized by means of a non-liquefied compressed gas, said container being provided with a distribution valve with additional gas intake and with a dip tube fixed to the body of valve, characterized in that the additional gas intake is made through a sintered element having dimensions and a porosity such that, under a pressure difference of 10 x 105 pascals, the flow of gas passing through the element

  sintered is between 10 and 50 cm 3 / sec.

  The sintered element used has, in general, pores with an average diameter of between 0.1 and 5 micrometers. The sintered elements are, in known manner, obtained by agglomeration, by heating and / or by compression of a pulverulent material such as glass, ceramic, metal or plastic, for example polyethylene. According to the present invention, preferably used , sintered elements sold by the company "POREX" under the trade name

"POROUS PLASTICS".

  It has been found that by using a sintered element as defined above in the additional gas intake, a finer spray is obtained without the pressure decreasing too quickly. The spray is more fine the higher the flow rate. ; it is therefore possible to operate with lower flow rates while still obtaining satisfactory spraying. For example, with a

  low flow rate of 0.5 g / s, we can obtain

  telettes with an average diameter of 75 micrometers.

  The additional gas flow rate depends on the dimensions and the nature of the sintered element, that is to say on the average path traveled by the gas in the sintered element and on the contact surface between the gas and the element. sintered For example, when

  the sintered element is a cylinder, it depends on the sec-

  tion and the length of this element. According to a first embodiment of the invention, the dip tube is located in the axis of the supply duct of the valve body and the additional gas intake is perpendicular to said supply duct; the sintered element may have the form

of a cylinder.

  According to a second embodiment of the invention, the additional gas intake is located in the axis of the supply duct of the valve body and the dip tube opens perpendicular to this

  axis; the sintered element may have the shape of a cylinder

  dre. According to a third embodiment of the invention, the sintered element has the shape of a ring arranged in the valve body, so as to surround the opening of the supply duct of the valve body, the gas intake additional being made entirely through said ring by means of openings made in the wall of the valve body in

vis-à-vis said ring.

  To better understand the object of the invention, we will describe below, by way of purely illustrative and non-limiting examples, several embodiments shown in the

attached drawing.

  In this drawing, FIG. 1 schematically represents, in

  axial section, a first embodiment of the arrangement

  sitive according to the invention, in which the gas outlet

  additional is perpendicular to the axis of the con-

  feed line from the valve body; Figure 2 schematically shows in partial axial section, a second embodiment, in which the sintered element is arranged in the axis of the supply duct of the valve body; FIG. 3 schematically represents, in partial axial section, a third embodiment, in which the sintered element is a ring arranged in the valve body and surrounding the opening of the supply duct of the valve body. The device represented in FIG. 1 is designated as a whole by the reference 1 It consists of a container 2, comprising a valve 3

  actuated by a push button 5.

  The container 2 is constituted by side walls of generally cylindrical shape closed at one end by a bottom (not shown) At the end opposite the bottom, the walls form a dome and the

  container is closed by a valve cup 4 3.

  The valve 3 is fixed to the center of the valve cup 4 which is fixed to the container 2

  by a crimping bead Said valve 3 com-

  carries an emerging rod 6, which is movable in transla-

  tion and emerges outside the container 2, and a valve body 7 which is fixed and which opens in the container 2; the valve stem 6 slides in the valve body 7 to cause the valve 3 to open. According to the embodiment shown, a push button 5 is fixed by interlocking on the emerging stem 6; it includes a cylindrical side skirt 5 a, the lower edge of which stops at a distance from the cup 4 and the upper edge of which is connected to a flat upper part 5 b, on which the user presses to actuate the valve 3 In the push button 5, is formed an ejection channel 8, this channel comprising two sections arranged at right angles; a first section 8 a is arranged coaxially with respect to the emerging rod 6 and a second section 8 b disposed at

  right angle opens in the side skirt by a cham-

  brage o is forced down a spray nozzle whose orifice 9 has a diameter very

  lower than that in section 8 b.

  The valve body 7 is provided with a tube 10 of smaller diameter forming a supply conduit for the valve body. On this tube 10 is force-fitted a dip tube 11 The additional gas outlet 12 opens in the body of valve 7; it consists of two right-angled sections 12 a and 12 b Section 12 a is perpendicular to the longitudinal axis of the container 2 and opens in the valve body 7 Section 12 b opens above the level liquid L to be sprayed Section 12 b contains a sintered element

  13 which has the shape of a cylinder and which we have introduced

duces by force.

  When the user presses part b of the push button 5, he pushes the valve stem 6 and actuates the valve 3; the liquid L rises in the

  dip tube pushed by compressed gas.

  Simultaneously, a small amount of compressed gas passes through the sintered element 13 of the additional gas intake 12 and enters the valve body 7 where it facilitates the ejection of the liquid L to be sprayed At the outlet of the emerging rod 6 , the liquid passes through the channel 8 and it is sprayed at the level of the orifice 9 It can be seen that one can thus obtain a satisfactory spraying from the start to the end of

the distribution.

  In FIG. 2 is shown schematically another embodiment of the invention. In this embodiment, the push button and the container as well as the valve are identical to those represented in FIG. 1 In order to simplify, only the cup designated by the reference 104 and the valve body 107 have been shown On the tube 110 forming the supply conduit for the valve body 107 is axially fixed an additional gas intake constituted by a conduit 112 provided with a lateral tube 112 a On this lateral tube 112 a is fixed a dip tube 111 bent at a right angle; the tube 111 is fixed to the lateral tubing 112 a, perpendicular to the longitudinal axis of the container; it extends, for the rest of its length parallel to the longitudinal axis of the container The sintered element 113 is cylindrical and it is forced into the conduit 112 below the lateral tube 112 a A result is obtained

  analogous to that indicated for the first embodiment.

In Figure 3 is shown

  schematically another embodiment of the provision

  spraying sitive according to the invention In this embodiment of the invention, the push button and the container are identical to those illustrated in FIG. 1 For simplicity, only the valve cup 204 and the valve body 207 have been shown The valve body 207 is delimited by a cylindrical side wall 214 closed at its base by a partition 215 perpendicular to the longitudinal axis of the container The partition 215 is connected in its central zone to a cylindrical nozzle 210 turned towards the inside of the container forming the supply duct of the body

  valve On this endpiece is fixed the dip tube 211.

  At the lower part of the side wall 214 and at the periphery of the partition 215 are formed lights 216 The sintered element 213 rests on the partition 215; it has an annular shape and its outside diameter is equal, apart from the necessary clearance, to the inside diameter of the side wall 214 and its inside diameter equal to the inside diameter of the end piece 210 The sintered element 213 has a thickness such that the openings 216 are fully opposite

the sintered element 213.

  During spraying, the compressed gas enters through the ports 216 in the element 213 and passes through it. Similar results are obtained

  to those described for the first embodiment.

  In a comparative test, a spraying device was used as illustrated in FIG. 1; the container of this device has an internal volume of 270 cm 3; contains 150 cm 3 of liquid

  to spray with a viscosity of 15 cps; gas pro-

  blower is compressed air, initially under 10 x 105 pascals; the orifice of the spray nozzle has a diameter of 0.20 mm. The results were compared without additional gas intake and with an additional gas intake containing a cylindrical polyethylene sintered element 2.4 mm in diameter and 1 , 75 mm

  in length having a pore diameter of 2-

  micrometers; the flow rate of the frit is cm 3 / sec at a pressure difference of x 105 pascals The flow rate of the liquid distributed and the average size of the droplets were measured

  sprayed at the start, middle and end of the dis-

  tribution The following results were obtained: with PGA without PGA Flow Diameter Flow Rate Diameter of g / sec droplets g / sec droplets Start 0.8 53 1.1 63 distribution Middle 0.65 65 O, 9 70 distribution End distribution 0, 50 75 0.75 80 PGA = additional gas intake With the spraying device with additional gas intake, a finer spray is obtained with lower flow rates than those measured with the

  spraying device without additional gas intake-

nelle. : 10

Claims (5)

  1 spraying device comprising a pressurized container (2) by means of a non-liquefied compressed gas, said container being provided with a valve (3, 103, 203) for distribution with additional gas intake and a tube diver (11, 111, 211),   characterized by the fact that the gas intake addition-   It is done through a sintered element (13, 113, 213) having dimensions and porosity such that under a pressure difference of 5 x 105 pascals, the gas flow passing through the sintered element is between 10 'and 50 cm 3 sec.   2 Device according to claim 1, characterized in that the diameter of the pores of the sintered element (13, 113, 213) is between 0.1 and 5 micrometers.   3 Device according to one of the claims   1 or 2, characterized in that the tube   plunger (11, 111, 211) is located in the axis of the   supply hose (10) of the valve and the intake   additional gas (12) is perpendicular to said con- supply hose (10).   4 Device according to one of the claims   1 or 2, characterized in that the taking of   additional gas is located in the axis of the supply duct   indication (110) of the valve and the dip tube (111)   opens perpendicular to this axis.   Device according to one of Claims 3 or 4, characterized in that the element   sintered (13, 113) has the shape of a cylinder.   6 Device according to one of the claims   1 or 2, characterized in that the sintered element (213) has the shape of a ring arranged in the valve body (207), so as to surround the opening of the supply duct f 210) of the valve body (207): the additional gas flow being made completely 1 1 through said ring by lights (216) provided   in the wall of the valve body and the apertures (216) being entirely opposite said sintered element (213).