NZ244338A - Flow regulator for aerosol container valve: rubber-elastic member forced against valve seat by internal pressure - Google Patents

Description

24 4 3 3 8 s t.t ' . . < .L. - • - > • 92-,, 27 APR P.O. J:• ::::;1!. l3>715^ No.: Date: COMPLETE SPECIFICATION FLOW REGULATING VALVE a* (I NEW ZEALAND - PATENTS ACT, 1953 We, DEUTSCHE PRAZISIONS-VENTIL GMBH, of SchulstraBe 33, 6234 Hattersheim 1, Federal Republic of Germany, hereby declare the invention for which pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- - 1 -(followed by page la) 244338 -la- •!' ' \ The invention relates to a flow regulating valve for a container containing a product which is capable of flow and which is exposed to a gas pressure and a delivery valve in a delivery duct so that the product issues through the delivery duct when the delivery valve is 5 opened, wherein the flow regulating valve has in the delivery duct a valve seat of hard material and a rubber-elastic regulating member which when the delivery duct is opened is urged against the valve seat by the internal pressure of the container and which constricts the through-flow cross-section of the delivery duct in the region of at 10 least one throttle duct forming a portion of the delivery duct less and less with decreasing internal pressure, in order to keep the through flow substantially constant.

In a known flow regulating valve of that kind (EP 234 797 Bl), the regulating member is in the form of a rubber disc with an axial 15 central- bore forming the throttle duct and a recess on the side which is towards the valve seat. When there is a high internal pressure in the container, the rubber disc is radially compressed so that the through-flow cross-section of the bore is narrowed down. With decreasing internal pressure, the narrowing of the bore is 20 correspondingly less and thus the through-flow cross-section is greater.. As the through flow is a function of the internal pressure and the through-flow cross-section, it remains substantially constant independently of the internal pressure. However rubber-elastic material has the property that it swells when it comes into contact 2 244338 with certain fluids, for example grease-bearing or oily fluids> as are frequently contained in such containers such as aerosol or spray cans.

In addition the nominal dimensions of rubber-elastic components cannot be maintained with close tolerances in manufacture, quite apart from the fact that they are temperature-dependent and change in the course of time due to ageing phenomena. As however the endeavour is to keep 2 the through-flow cross-section very small, for example about 0.2 mm , in order to avoid unnecessary consumption of the product contained in the container, the through flow is dependent to a considerable extent 10 on the nominal dimensions of the regulating member being accurately maintained.

The invention is based on the problem of providing a flow regulating valve of the general kind set forth, in which the through flow is maintained with a higher degree of accuracy.

In accordance with the invention that problem is solved in that the throttle duct is delimited by a groove in the valve seat and the regulating member.

In that solution, the throttle duct is delimited for the predominant part by the groove and only for a small part by the rubber- ♦ f elastic regulating member. As the groove is provided in a hard material which can be made with narrower dimensional tolerances than a rubber-elastic member and from a material which on the one hand does not swell and which on the other hand is subject to minor ageing phenomena, overall the through-flow cross-section of the throttle duct 25 can be made and maintained more accurately than that of a bore in a rubber-elastic material. In a corresponding fashion the through flow can also be very accurately set and maintained so that it is possible to consume the product contained in the container as sparingly as possible, substantially independently of fluctuations in the internal 30 pressure in the container, the rubber-elastic regulating member being 3 2 4 4 3 3 pressed into the groove to a greater or lesser extent in dependence on the internal pressure and in that way keeping the flow constant.

It is preferably provided that the valve seat is formed by a shoulder surface in a connecting portion for a dip tube, the connecting 5 portion being provided on the housing of the delivery valve. That configuration requires only minor modification to conventional delivery valves of spray cans.

Alternatively it is possible for the valve seat to be formed by a shoulder surface in a part of the delivery duct which passes through an 10 actuating fitment of the delivery valve for the container. In that arrangement the conventional "delivery valve does not have to be changed at all while in the case of the conventional actuating fitment, only a minor alteration is required.

Preferably the valve seat is formed by a substantially conical 15 shoulder surface. That automatically provides for centering of a regulating member of corresponding shape.

Thus the surface of the regulating member which co-operates with the valve seat can be formed by at least a part of a spherical or a conical surface. A spherical surface has the advantage that the 20 contact surface area between the valve seat and the regulating member is correspondingly small and accordingly the pressure required to achieve deformation of the regulating member, for determining the through-flow cross-section of the throttle duct, can also be correspondingly low. In contrast the conical surface has the advantage 25 that it is simpler to produce.

It can then be provided that the spherical surface is formed by a part of the surface of a spherical zone, the flat surfaces of which each form a respective one of the base surfaces of a cylinder, the outside diameter of which is somewhat smaller than the inside diameter 30 of a portion of the delivery duct, which is disposed around the 2 4 4 3 3 8 respective cylinder. In that way the cylinders additionally,provide for guidance of the regulating" member in the delivery duct without impeding the through flow.

The base surface of the cone can also at the same time form the 5 base surface of a cylinder, the outside diameter of which is somewhat smaller than the inside diameter of a portion of the delivery duct, which is disposed around the cylinder. In that configuration the cylinder also provides for an additional guidance effect without impeding the through flow.

It can then be provided that at least one narrow by-pass duct communicates the region, which contains the compressed gas, of the container upstream of the regulating member, through the housing of the delivery valve, to the delivery duct. That narrow by-pass duct permits mixing of the compressed gas contained in the container with the 15 issuing product when the delivery valve is opened so that on the one hand the arrangement provides that the product is consumed even more sparingly when the delivery valve is opened while on the other hand providing finer distribution of the product in the form of particles on issuing from the spray head of the container.

If the by-pass duct ends eccentrically in a swirl chamber through which the delivery duct passes, that provides for still better mixing of product and compressed gas.

The invention and developments thereof are described in greater detail hereinafter with reference to the drawings of preferred 25 embodiments in which: Figure 1 is a view in axial section through a delivery valve with a flow regulating valve according to the invention in a valve carrier of a spray container (not shown), the regulating valve being in the form of a spherical zone with axial extensions in the form of 30 cylinders, 24 4 3 Figure 2 is a view frcm below of the housing of the delivery valve shown in Figure 1, Figure 3 is a view in axial section of the housing of the delivery valve shown in Figures 1 and 2 with a regulating member in the 5 form of a ball, Figure 4 is a view in axial section of the housing of the delivery valve shown in Figures 1 and 2 with a regulating member in the form of a cone and a cylinder formed at the base surface thereof, Figure 5 shows a mcdified flow regulating valve as shown in 10 Figure 1, in accordance with the invention, having an insert with a swirl chamber, Figure 6 is a view from below of the insert shown in Figure 5, Figure 7 shows a modification of the valve housing shown in Figure 1, Figure 8 is a view frcm below of the valve housing shown in Figure 7, Figure 9 is a modification of the valve housing shown in Figure 7, Figure lO is a view from below of the valve housing shown in 20 Figure 9, Figure 11 shows a further embodiment of the invention in which the regulating valve is inserted in the actuating fitment of a delivery valve, Figure 12 is a view from below of the actuating fitment shown in 25 Figure 11, Figure 13 shows a modification of the actuating fitment shown in Figure 11, Figure 14 is a view from below of the actuating fitment shown in Figure 13, and Figure 15 is a modification of the actuating fitment shown in Figure 13. . k."-. I-.-, ^ ll < » V? W/ As shown in Figures 1 and 2, the housing 1 of a delivery valve is fixedly inserted in a valve carrier 2. The valve carrier 2 forms the upper part of a top of a container containing a product which is capable of flow and which exposed to a gas pressure. The seal between 5 the top and the valve carrier 2 is made by means of a rubber seal 3. The valve housing 1 is fixed in the valve carrier 2 by a radially inward peripheral wall 4 of the valve carrier 2 being provided at a plurality of peripheral locations with inwardly impressed bulge portions 5 which engage under a flange 6 of the valve housing 1. By 10 virtue of that arrangement, a clamping edge 7 which is provided at the top side of the valve housing 1 presses a rubber-elastic sealing disc 8 against an end wall 9 of the valve carrier 2. A hollow valve shank 10 engages through a central hole in the sealing disc 8. The edge of the hole bears against a constriction 12 in the valve shank 10, in which 15 there are transverse holes 13 which communicate with the internal cavity in the valve shank lO. A valve actuating fitment with spray nozzle or the like can be fitted onto the valve shank 10 in the usual way. The valve shank 10 is urged upwardly by a spring 14. The cavity 15 which accommodates the spring 14 is communicated with the interior 20 of the container by way of a duct 16 which extends through a connecting portion 17 for fitting a dip tube 18 thereon. When the valve shank 10 is depressed by means of the actuating fitment, the edge of the hole in the sealing disc 8 is bent downwardly £>y the constriction 12. As a result the transverse holes 13 are exposed and a delivery duct is 25 opened, which leads frcm the interior of the container outwardly through the connection 17, the cavity 15, the transverse bores 19 and the cavity in the valve shank lO.

Between the peripheral wall 4 of the valve carrier 2 and the 2q peripheral wall of' the valve housing 1, there remains an annular deflection space 19 for the material of the sealing disc 8 and filling ducts 19 which join thereto and which communicate the deflection space -t i- " D L ^ 4 3 3 with the interior of the container outside the housing 1. A central hole is provided in the end wall 9 so that there is an annular filling opening 21 around the valve shank 10.

In the filling operation, care is taken to provide that the fluid 5 to be introduced passes not only through the cavity in the shank 10 into the interior of the container but also through the filling opening 21. When that happens the filling pressure axially corrqpresses the sealing disc 8 in the clamping region and presses it into the deflection space 19. Consequently a gap is exposed between the sealing 10 disc 8 on the one hand and the end wall 9 and the peripheral wall 4 on the other hand, and the fluid to be introduced can flow through that gap into the container. In addition the fluid to be introduced can also be introduced by way of the delivery duct when the delivery valve is open.

A flow regulating valve is also provided in the duct 16 of the connection 17. It has a valve seat 22 in the form of a conical shoulder surface in the connecting portion 17. Provided in the valve seat 22 is a groove 23 which extends in the flow direction and which, together with a regulating member 24 of rubber-elastic material, delimits a throttle duct;" The surface of the regulating member 24, which co-operates with the valve seat, is formed by a part of the surface' of a spherical zone, the flat surfaces of which each form one of the base surfaces of a cylinder 25 and 26 respectively. The outside diameters of the cylinders 25 and 26 are somewhat smaller than the inside diameter of the portion of the delivery duct, which is disposed around the respective cylinder 25 or 26. When the regulating member 24 is introduced into the connection 17 it is pressed beyond radially 2-? inwardly projecting bevelled securing projections which are formed on the inside of axial bar portions 28. The bar portions 28 are separated 30 from each other by slots 29.

The regulating member 24 is emitted from the view from below in Figure 2, for the sake of simplification of the drawing. 2 4 4 3 3 8 8 I i When the delivery valve is opened by the valve shank 10 being depressed, the regulating member 24 is immediately pressed against the valve seat 22 by the product or fluid which flows out under the gas pressure obtaining in the container, as shown in Figure 1, so that the 5 flow of product through the throttle duct which is delimited by the groove 23 and the regulating member 24 is throttled. At the beginning of the emptying operation, when the container is still full, a high gas pressure still obtains in the container. That causes the rubber-elastic material of the regulating member 24 to be partially pressed 10 into the groove 23 and substantially constrict the throttle duct, at the point of contact .between the valve seat 22 and the regulating member 24, so that a correspondingly smaller amount of product issues. If on the other hand the gas pressure decreases in the course of emptying of the container, the pressure applied to the regulating 15 member 24 also decreases so that it penetrates into the groove 23 to a lesser depth and the through-flow cross-section of the throttle duct is somewhat increased. In that way the arrangement ensures that, irrespective of the internal pressure in the container, the through flow of product through the throttle duct remains substantially 20 constant and econonomical■consumption of the product is guaranteed.

The housing 1 comprises a material, for example plastics material or metal, which is comparatively hard in comparison with the rubber-elastic material of the regulating member 24. The groove 23 can therefore be produced with comparatively close dimensional tolerances. 25 Its dimensions are then less dependent on temperature or ageing. Admittedly the dimensions of the rubber-elastic regulating member 24 can only be maintained with greater tolerances and are to a higher degree dependent on temperature and subjected to changes caused by ageing. As however only a small part of the surface of the regulating 30 member 24 delimits the throttle duct, the dimensions of the throttle duct can nonetheless be maintained more accurately overall and are less 9 24 4 3 38 .»< i temperature-dependent and less subject to changes caused by'ageing, than a throttle duct which is delimited over its entire periphery by a rubber-elastic material. The conical surface of the valve seat 22, in conjunction with the spherical surface of the regulating member 24, 5 which bears thereagainst, provides for centering of the regulating member 24 in the valve seat 22 so that the regulating member 24 bears sealingly against the valve seat over the entire periphery of its spherical portion, except for the groove 23, while the cylinders 25 and 26 serve for guiding the regulating member 24 in the delivery duct and 10 the annular space surrounding them allows the product to pass through unimpededly.

As soon as the delivery valve is no longer actuated, that is to say the valve shank 10 is no longer being pressed down, the spring 14 urges the valve shank 10 back into the illustrated position in which 15 the delivery valve is closed and then the regulating member 24 drops down again under its own weight until it bears against the securing projections 27.

Figure 3 shows a modification of the flow regulating valve illustrated in Figure 1, in which there is a regulating member 24a in 20 the form of a ball, in place of the regulating member 24. All other details are identical to the embodiment shown in Figure 1, for which reason Figure 3 only shows the housing 1 with the flow regulating valve. The mode of operation of the flow regulating valve illustrated in Figure 3 also corresponds to that of the flow regulating valve shown 25 in Figure 1.

The modification illustrated in Figure 4 also differs from the embodiment shown in Figure 1 only by the regulating member 24b which has a cone 30. The base surface of the cone 30 at the same time forms the base surface of the cylinder 26, the outside diameter of which is 30 smaller than the portion of the delivery duct, which is disposed around 2 4 4 3 3 8 i ..I i the cylinder 26. The mode of operation of that flow regulating valve also corresponds to that of the flow regulating valve illustrated in Figure 1.

The modification shown in Figures 5 and 6 only differs from that 5 shown in Figure 1 in that a housing portion la which extends the housing 1 is fitted with a press fit onto the connecting portion 17 of the housing 1, and in turn has a connecting portion 17a into which the dip tube 18 is fitted with a press fit. The housing portion la then has an intermediate wall 31 with a bore 32 therethrough, and a 10 substantially cup-shaped insert 33 is inserted between the lower end of the connecting portion 17 and the intermediate wall 31. In its underside the insert 33 has a swixl chamber 34 which conmunicates by way of narrow grooves 35 opening tangentially into the swirl chamber 34, with an annular space 36 which in turn communicates by way of a 15 slot 37 in the peripheral wall of the housing portion la with the region of the interior of the container, which is filled with compressed gas. A coaxial bore 39 also extends through the bottom 38 of the insert 33 and is aligned with the swirl chamber 34 and the bore 32. The grooves 35 on the underside of the insert 33 are closed 20 downwardly by the intermediate wall 31. With the annular space 36 and the slot 37 they form a narrow by-pass passage through which the compressed gas can pass into the swirl -chamber 34, flows tangentially thereinto and is mixed with the product which issues through the bore 32 upon actuation of the delivery valve, with the product being divided 25 into fine particles. In that way there is an additional throttle action in the delivery duct, which ensures still more economical consumption of the product.

The embodiment shown in Figures 7 and 8 only differs from that shown in Figure 1 in that upstream of the flow regulating valve, in its 30 side wall, the housing 1 has fine bores 40 which extend radially through the side wall to the delivery duct and which also form a narrow 2 4 4 3 3 8 11 by-pass duct for the discharge of compressed gas and mixing>. thereof with the product upstream of the" throttle duct.

The embodiment shown in Figures 9 and 10 only differs from that shown in Figures 7 and 8 in that the shoulder of the housing 1, which 5 adjoins the connecting portion 17, has radial grooves 41 and the outside of the connecting portion 17 has narrow axial grooves 42 which are aligned with the radial grooves 41 and which are closed by the dip tube 18 except for their ends and in that way form an equally narrow (microfine) by-pass duct as the bores 40.

The embodiment shown in Figures 11 and 12 essentially only differs from that shown in Figures 5 and 6, in the following respect. The housing lb is of a one-part configuration and does not contain the flow regulating valve. On the contrary the flow regulating valve is contained in a cap-like actuating fitment 43 for actuation of the 15 delivery valve, more specifically in a connecting portion 45 which is formed on the end portion 44 of the actuating fitment 43 which is also made from hard plastics material or metal, the upper end portion of the valve shank 10 being inserted with a press fit in the connecting portion 45. Provided in the conical valve seat 22 in the connecting 20 portion 45 are a plurality of grooves 23 which, together with the regulating member 24, form the regulatable throttle duct. A plurality of axial grooves 46 are also provided in the cylinder 26 of the regulating member 24, being arranged in a distributed array over the periphery thereof. Downstream of the flow regulating valve, a radial 25 bore 47 joins the portion of the delivery duct which is delimited by the connecting portion 45. The radial bore 47 terminates in an annular groove 48. A substantially cup-shaped nozzle insert 49 is a snug fit in the annular groove 48. On the radially inward side of its end portion, the nozzle insert 49 also has a swirl chamber 50 which is leading to the annular space 51. Also provided in the bottom of the communicated with the by way of tangential ducts and bores 2 4 4 3 3 8 12 chamber 50 is a coaxial bore 52 forming the discharge nozzle. The mcde of operation is the same as that of the errbodiment illustrated in Figures 5 and 6.

The embodiment shown in Figures 13 and 14 only differs from that 5 illustrated in Figures 11 and 12 in that, instead of the regulating member 24, it has the regulating member 24b and only one groove 23. The nozzle insert 49 which is fitted in the annular groove 48 is omitted from Figure 13 for the sake of simplicity of the drawing.

The embodiment shown in Figure 15 only differs from that shown in 10 Figures 13 and 14 in that it has the regulating member 24a instead of the regulating member 24b.

Claims (10)

WHAT WE CLAIM IS:

1. A flow regulating valve for a container containing a product which is capable of flow and which is exposed to a gas pressure and a delivery valve in a delivery duct so that the product issues through the delivery duct when the delivery valve is opened, wherein the flow regulating valve has in the delivery duct a valve seat of hard material and a rubber-elastic regulating member which when the delivery duct is opened is urged against the valve seat by the internal pressure of the container and which constricts the through-flow cross-section of the delivery duct in the region of at least one throttle duct forming a portion of the delivery ductless and less with decreasing internal pressure, in order to keep the through flow substantially constant, characterised in that the throttle duct is delimited by a groove in the valve seat and the regulating member

2. A flow regulating valve according to claim 1 characterised in that the valve seat is formed by a shoulder surface in a connecting portion for a dip tube , which connecting portion is provided on a housing of the delivery valve.

3. A flow regulating valve according to claim 1 characterised in that the valve seat is formed by a shoulder surface in a part of the delivery duct which passes through an actuating fitment of the delivery valve for the container.

4. A flow regulating valve according to one of claims 1 to 3 characterised in that the valve seat is formed by a substantially conical shoulder surface. 14 0 Z T *W *■« *s i ^ w

5. A flow regulating valve according to claim 4 characterised in that the surface of the regulating member which cooperates with the valve seat is formed by at least a part of a spherical or a conical surface.

6. A flow regulating valve according to claim 5 characterised in that the spherical surface is formed by a part of the surface of a spherical zone, the flat surfaces of which each form one of the base surfaces of a respective cylinder , the outside diameter of which is somewhat smaller than the inside diameter of a portion of the delivery duct, which is disposed around the respective cylinder •

7. A flow regulating valve according to claim 5 characterised in that the base surface of the cone at the same time forms the base surface of a cylinder , the outside diameter of which is somewhat smaller than the inside diameter of a portion of the delivery duct, which is disposed around the cylinder

8. A flow regulating valve according to one of claims 1 to 7 characterised in that at least one narrow by-pass duct communicates the region, which contains the compressed gas, of the container upstream of the regulating member to the delivery duct, through a housing of the delivery valve.

9. A flow regulating valve according to claim 8 characterised in that the by-pass duct terminates eccentrically in a swixl chanter through which the delivery duct passes.

10. A f low regulating valve substantially as herein described with reference to the accompanying drawings. , i iogjjnl (4 Hy the authorised agents ■\ J PAHK & SON ' .. .