NO123602B - - Google Patents

Description

Device for non-return valve and/or pump.

The present invention relates to a device for a non-return valve and/or pump comprising an elastomer element, preferably formed in one piece, comprising resp. is adapted to cooperate with a bottom element with a surface and through which two openings open out, which elastomer element comprises a retracted part with a peripheral edge, which is adapted to seal the retracted part against said surface for together with this to form* a closed chamber communicating with the two apertures, the retracted part having at least one partition having an edge adapted to rest resiliently across and against said surface between the apertures, such that the partition or walls divide the chamber in respectively • two.or more departments, two of which communicate with each other - opening,.which, dividing wall resp. -walls form an acute angle with any line in one of the compartments (the second compartment at one partition or the third at two partitions) which is (a) tangent to the said surface where it extends the edge, and (b) normal to the edge.-Such devices are used e.g. in containers for window sprays where they form a pump device to deliver the spray in small quantities in the form of a shower or jet, and where the partition wall resp. -the walls serve as non-return valve means in the pump device to prevent the fluid from flowing back in the opposite direction to the direction of supply. In the case of a known device (U.S. patent no. 2,715, 236) which in certain respects is similar to the initially stated device, the inclined dividing wall does not reach down to said bottom surface when the device is in a resting position and the dividing wall will thus not function as a non-return valve in this position. This inclined partition is arranged in a "cantilever"-like manner, i.e. it is only connected to the inner surface of the container opposite the bottom surface, so that its resistance to bending in the direction of the feed direction is relatively small.

In another known device (U.S. patent no. 3,013-502) of the nature indicated at the outset, a number of inclined partitions are likewise arranged in the aforementioned "cantilever"-like manner hanging from a membrane, which is clamped along its entire circumference between adjacent edges of two container halves, so that the membrane divides the container into an upper chamber, into which gas can be introduced under pressure, and a lower chamber, in which the inclined partitions are located and at the opposite ends of which an inlet and an outlet are respectively arranged. When said membrane is affected by pressure from above, it will bulge downwards in the chamber in which the partitions are arranged. A downward pressure at the center of the membrane will cause the partitions to bend up and lie flat against the inside of the membrane, so that the intended pumping effect from the inlet to the outlet is not achieved. The "cantilever"-like way in which these partitions are arranged gives them little resistance to withstand pressure in the opposite direction to the feed direction, as pressure in the direction from the outlet will cause the partitions to bend backwards in the direction of the inlet.

The purpose of the invention is to remedy these disadvantages, which has been achieved by the dividing wall resp. -the walls over their entire circumference, with the exception of said edge, are connected to the elastomer element, as the inherent resistance to stretching in the material of the partition resp. -walls will result in said edge resisting movement in the direction of the compartment in which the dividing wall or the walls form an acute angle with said surface. This fixing method for the partition or - the walls according to the invention will mean that they will resist a significant back pressure (i.e. from the outlet) without the edges cooperating with the bottom surface being lifted up from this and the partition walls bending in the direction of the outlet.

Four embodiments of the invention are shown in the drawings, there

the same reference number is used for corresponding parts in all drawings, and where: -

Fig. 1 is a perspective view of a non-return valve according to a first embodiment of the invention; Fig. 2 is an axial section through the check valve according to fig. 1; Fig. 3 is a perspective view of a pump according to another embodiment of the invention; Fig. h is a section through the pump according to fig. 3; Fig. 5 and 6 are sections corresponding to fig. ^, and illustrating two phases in the pump's working process; Fig. 7 is a perspective view, seen from below, of a pump according to a third embodiment of the invention; Fig. 8 shows a fourth embodiment of the invention, seen from below; Fig. 9 is a vertical longitudinal section through the fourth embodiment; and Fig. 10 is a vertical section through a container cap or lid construction according to the fourth embodiment of the invention. -

Reference is first made to fig. 1 and 2, where a non-return valve designated in its entirety by the reference number 10 consists of a cylindrical base piece 11 with an inlet channel 12 and an outlet channel 13, which channels 12, 13 are both parallel to the axis of the cylindrical base piece 11. The upper surface lh of the cylindrical foot piece 11 thus has two openings, namely a first opening 16 which communicates with the inlet channel 12 and a second opening 18 which communicates with the outlet channel 13. As shown, rudders or hoses 19 can be arranged for the channels 12 and 13. -

An undivided elastomer element 20 includes a recessed or retracted portion 22 with a peripheral rim 23 which seals the recessed portion 22 against the surface lh to form together with this a closed chamber 2h which communicates with the two openings 16 and 18. The retracted portion 22 has a dividing wall 26 whose edge 28 is arranged to lie springily against the surface lh between the two openings 16 and 18, thereby dividing the chamber 2h into two compartments, namely a first compartment 30 which communicates with the opening 16 and a second compartment 32 which communicates with the opening 18. It will be seen that the partition wall 26 is mainly planar (flat), and that it extends obliquely in relation to the surface lk. -

In this connection, it should be pointed out that it is immaterial whether the surface 1<*>+ is flat or not. Firstly, the shape of the surface lh is only of importance in the central area where it touches the edge 28

of the partition 26. The shape (profile) of the surface lh within the two compartments 30 and 32 has no effect on the function of the non-return valve 10. However, should the surface lk- near the edge 28 be other than plane, correct operation of the non-return valve will require that the partition runs obliquely to any line which (a) is tangent to the surface 1*+ where it touches the edge 28, and (b) is perpendicular to the edge 28. To define this criterion in another way, all solid angles (two-plane angles) between the partition wall 26 and the imaginary plane tangent to the surface lh along the line of contact between the partition wall 26 and the surface lh must be acute on one side of the partition wall. -

Although the one in fig. 1 and 2 shown partition wall 26 is mainly flat (plane), this is an unimportant feature when it comes to correct function of the non-return valve. Deviations from a plane or flat shape are permissible without damage to the function, and it will later be shown in connection with a pump construction that a special curvature of the partition wall can bring special advantages. -

It will be seen that an outwardly directed flange 33 in one with the peripheral rim 23 extends from the latter, the diameter of the flange 33 being equal to the diameter of the cylindrical foot piece 11. The flange 33 is, although it is rather immaterial to the invention, useful to attach the elastomeric element 20 to the surface lM-, e.g. using glue. - The term "elastomer" as used herein is intended to include polymeric substances exhibiting appropriate elastic springing (resilience; deformation energy); and thus covers within its limits natural and synthetic types of rubber, and a large number of plastic materials with elastic properties. Of the enormous number of suitable elastomers, the following materials have been tested and found to be satisfactory as materials for the formation of the undivided elastomeric element according to all four embodiments: -

plasticized (softened) PVC ethyl vinyl acetate

styrene-butadiene rubber

butyl rubber

natural rubber

silicone rubber

The choice of material for the application in question is of course dependent on economic considerations, as well as the performance criteria for the particular application and the discharging properties of the fluid that is pumped or operated at the valve. -

As can best be seen from fig. 2, the elastomeric element 20 cooperates with the surface lh to form a check valve between the openings 16 and 18. Fluid can flow in the direction from the opening 16 to the opening 18, but not in the opposite direction. The reason for this is the inclined position of the partition wall 26. If fluid pressure in the compartment 30 rises above the pressure in the compartment 32, there will be a fluid pressure which acts perpendicularly on the partition wall 26, and this pressure is thus directed so that it lifts the lower edge of the partition wall 26 upwards and away from the surface 1^-, thereby allowing fluid to pass from the compartment 30 to the compartment 32 below the edge 28. If, however, the fluid pressure in the compartment 32 exceeds the fluid pressure in the compartment 30, the resulting pressure acting perpendicularly on the partition wall 26 will push the latter down, and the result is that the edge 28 is pressed more firmly against the surface 1<*>+, thereby preventing the transfer of fluid from the chamber compartment 32 to the chamber compartment 30. -

Although the retracted part 22 in the embodiment in fig. 1 and 2 are substantially hemispherical, it will be understood that correct operation of the check valve is not dependent on the hemispherical shape, provided that the outer wall is sufficiently thick to resist "inflation" deformation caused by high fluid pressure in the chamber 32. With this caveat, the recessed portion may 22 have elliptical or rectangular horizontal section, rectangular vertical section, etc. However, if the hemispherical wall is sufficiently thin to be deformed by fluid pressure, any shape other than the hemispherical one may deform in the direction of a hemisphere under high fluid pressure as a result of "inflating" - the effect. This deformation can result in the partition wall 26 lbft being raised from the surface lh, whereby the counter pressure sealing effect is cancelled. -

Reference is now made to fig. 3, which shows a pump attachment 36 for use in connection with a container 37' This attachable pump device 36 includes a foot piece 38 which has an internally threaded coupling h0 for cooperation with the neck h2 of the container 37. The foot piece 38 extends obliquely upwards to form of an angle with the coupling hO, and this upwardly extending part will be referred to hereafter as the disk-shaped element V3. In the embodiment shown, this disk-shaped element ^3 has an upper, planar inclined surface kk from which a hole k5 extends through the disk-shaped element ^3. The foot piece also comprises a channel Mo which puts the surface Mf in connection with the interior of the coupling MO. A rudder M3 communicates with the channel Mo and extends downwards from this into the container 37' -

An undivided electric elastomer element 50 is arranged with a retracted part 51 in sealing contact with the surface M+ to form together with this a closed chamber which communicates with the hole M5 and the channel MS. -

As can best be seen from fig. h the recessed part 51 contains two partitions 53 and 5^ which divide the chamber into a first compartment 56, which communicates with the hole Mp, a second compartment 58, which communicates with the channel Mo, and a third compartment 60 between the partitions 53 and 5<* >+ and thus located between the first and second ward 56 resp. 58. Each partition 53 and 5*+ has an edge 6l resp. 62, arranged to lie spring-loaded against the surface M+. Both partition walls 53 and 5M slope in the same direction with respect to the surface M+, the slope being such that the surface M+ within the first compartment 56 forms an obtuse angle 6h with the partition wall 53 which limits the first compartment 56. Those in fig. 3, ^» 5 and 6 shown partitions 53 and 5<*>+ are mainly flat (plane). -

The third compartment 60 has an upward bulge 66, the purpose of which will be explained with reference to fig. 5 and 6. -

Fig. 5 and 6 illustrate two phases in the pumping when the pump 36 is used to pump liquid. It will be understood from the following that the in fig. The pump shown in 3-6 can also be used for pumping gases. In fig. 5, it is assumed that liquid has already been drawn up into the second compartment 58, but that the liquid has not yet entered the third compartment 60. In fig. 5, there is also an inward pressure on the bulge 66 as indicated by the arrow. As a result, the bulge 66 is "turned" into the third compartment 60, and has presumably reduced the volume of the latter and thus increased the pressure of the air in the compartment. The increased air pressure in the compartment 60 presses the edge 62 of the partition wall ^\ firmly against the surface M+, and causes the edge 61 of the partition wall 53 to lift up from the surface M+, so that air is allowed to pass from the compartment 60 to the compartment 56 and then escape release via the hole M?. When the inwardly directed pressure on the bulge 66 is lifted, it returns to its outwardly directed position as shown by the arrow in fig. 6. The outward movement of the bulge 66 causes the volume of the compartment 60 to increase, thereby reducing the pressure in the compartment 60 relative to the compartments 56 and 58, and this causes the edge 62 of the partition wall 5h to lift up from the surface M+ to provide liquid opportunity to pass from the compartment 58 to the compartment 60, and further causes the edge 61 of the partition wall 53 to be pressed firmly and sealingly against the surface M+.

It should now be obvious that the next inward pressure or stbt on the bulge 66 will close the partition wall 5<*>+ and open the partition wall 535 whereby essentially the same amount of liquid remains in the compartment 60 as shown in fig. 6. Cessation of the inward pressure on the bulge 66 will then cause the partition wall 53 to close and the partition wall 5<*>+ to open and allow more liquid to pass from the second compartment 58 to the third compartment 60. This operation is continued until the third compartment 60 is full, after which liquid will be pumped into the first compartment 56 and then out through the hole V?. -

Reference is now made to fig. 7, where a third embodiment of the invention is illustrated, - with a different shape of the partitions 53 and 5<*>+. The partitions 53 and 5^ in fig. 7 slopes to the same extent as those in fig. 3, but instead of being flat, the former are curved, preferably mainly cylindrical. More specifically, the intersection lines between the partitions in fig. 7 and imaginary planes normal to the surface kh and parallel to the longitudinal axis of the elastomeric element 50, the said intersection lines being furthermore mainly straight, while the intersection lines between the partitions and imaginary planes parallel to the surface hh are curved, the centers of curvature of the latter intersection lines being on the same side of each partition as the section in which the angle between the relevant partition and the surface is obtuse. -

The reason for choosing curved partitions in fig. 7 is as follows: When the partitions are flat, passage of fluid is required under them

that the partitions are stretched as well as bent as the partitions are extended in one piece with the sides of the part 51, and the lower edges of the part 51 are attached to the surface M+. By bending the partitions on it in fig. 7 shown way, however, fluid passage from one compartment to the other under a partition only requires a bending of the partition. The proposed form of a curved partition is in fig. 7 shown in connection with the partition wall 53. It will be seen that the central part of the partition wall near the edge is in some way reversed, which makes it possible for the edge to be moved a considerable distance up from the surface hh without the restraining effect that occurs in connection with the stretching of the planar partition in fig. 3. -

It will be understood that a curved partition wall could also be used in the non-return valve according to fig. 1 and 2, with the same advantage. -

It should be noted that the bulge 66 in connection with the second and third embodiments of the invention is not vital for the function of the pump. The one in fig. 3 - 6 shown pump would also work satisfactorily even if the undivided elastomeric element 51 had a constant cross-sectional profile without bulge 66, provided that inward pressure across the compartment 60 would cause the volume of the latter to decrease. The arrangement of the bulge 66, however, allows a greater volume change in the compartment 60, and therefore enables greater pumping capacity and pumping speed.

Although in connection with the second and third embodiments of the invention as shown in fig. 3-7 it is preferred that the surface kk is mainly flat, this is not an unconditional prerequisite for the invention. Firstly, the shape of the surface kk is only of importance in the central area where it touches the edges 61 and 62 of the partitions

53 and 5*+. Secondly, the shape of the surface kk can also in this intermediate part deviate from flat to some extent without disturbing the pump's function. For example, the surface kk can be spherical or cylindrical, concave or convex, in the intermediate areas where it touches the edges 61 and 62. The shape of the surface kk within the compartments 56, 58 and 60 has no effect on the function of the partitions 53 and 5k. Regardless of whether the surface kk in the areas immediately close to the edges 61 and 62 is flat or curved, it is assumed that correct function of the 1 fig. 3 - 7 shown pump requires that the first partition wall 53 forms an acute angle with any line in the third compartment 60 which is (a) tangent to the surface kk where it touches the edges of the first partition wall 53, and (b) normal to the edge 6l of the first partition 53, and that it is also required that the second partition 5k forms an acute angle with any line in the second compartment 58 which is (a) tangent to the surface kk where this touches the edge 62 of the second partition 5^, and (b) normal to the edge 62 of the second partition 5k. This criterion can be expressed in another way, namely as indicated in connection with the non-return valve 10 in fig. 1 and 2: all solid angles (two-plane angles) between each partition and the imaginary plane that is tangent to the surface kk along the contact line between a relevant partition and the surface kk must be acute on one side of the partition. -

Fig. 8, 9 and 10 show a fourth embodiment of the invention, which embodiment differs only to a minor extent from the second embodiment according to fig. 3-6. Fig. 9 is a section, while Fig. 8 is a view from below, of an elastomer element 70 which is largely elliptical in plan, and hump-, bladder- or dome-shaped in profile and in vertical section. As in the other embodiments, a retracted part 71 has a circumferential edge 72 which is adapted to seal the retracted part 71 against a surface 7k of a cloud-shaped element 75 (fig.

10). In order to improve the seal between the edge 72 and the surface 7k, a protruding bead 77 is formed on the underside of the edge 72, see fig. 9. A first partition wall 78 and a second partition wall 80 are designed to fulfill the same functions as their corresponding parts 53 and 5<*>+ in the second embodiment in fig. 3-6. In fig. 10 is the closed chamber 82, which is limited by the surface 7<1>* and. the recessed part 70, divided by the partitions 78 and 80 into a first compartment 8h, a second compartment 85 and a third compartment 86. The disc-shaped element 75 has a first opening 88 which opens out

in the first compartment 8<*>+, and another opening 90 which is arranged to open u-t in the second compartment 85. The disk-shaped element 75 has a projecting part 92, on which is fitted a nozzle cap 93 with a nozzle 9k. The nozzle 9<*>+ cooperates with the opening 88 as shown in fig. 10. The opening 90 communicates with a vertical rudder 96 arranged to extend downwardly into a container with a threaded neck, onto which a screw cap 98 can be screwed. The screw cap 98 is integral with the disk-shaped element 75- -

A conical cap 110 is formed to fit snugly over the entire construction and has abutment surfaces 102 adapted to press the edge 72 of the elastomeric element 70 against the surface 7*+' The cap 110 also has an opening 10h to allow passage of the advancing part 92 of the disk-shaped element 75, as well as a largely circular opening 106, through which part of the elastomeric element 70 protrudes, as shown in fig. 10. Around the bottom of the cap 110 there is a rim 107 which is designed to fit over the circumference of a disc-like, horizontal plate part 108 which forms a part formed in one with the disc-shaped element by a snap or snap action. -

The main difference between the second embodiment and the fourth embodiment according to the invention is as follows: Firstly, the partition walls 78 and 80 form a steeper acute angle with the surface Jh. Forsbk has shown that the real value of the angle between a particular partition and the surface can vary within wide limits, provided that the angle remains acute. Secondly, the lower edges 110 and 111 of the partitions 78 resp. 80 approx. 30° in the same direction as the slope of each partition wall 78 and 80 (fig. 9). The thereby achieved knife-edge seal between each partition wall and the surface 7<*>+ is believed to improve the efficiency and resistance to leakage in the fourth embodiment.

It will be seen in fig. 9 that the sloping bottom edges 110 and 111 of the partitions extend down a distance corresponding to the depth of the bead 77' When the elastomeric element 70 is clamped in place as shown in fig. 10, the bead 70 is flattened to some extent and pressed together upwards and into the material by the edge 72, which is the reason why the bead 77 is not visible in fig. 10. -

Due to the upward compression of the bead 77, the lower edges 110 and 111 of the partitions 78 and 80 are pressed positively against. the surface 7^5 which results in a slight curvature at the edges which is visible in fig. 10. The first and second difference mentioned above can also be used with the non-return valve according to the invention. The non-return valve can also be fitted with a bead corresponding to the bead 77 in fig- 9} for the same purpose as there. Finally, an alternative variation is suggested in fig. 10, where the surface of the disk-shaped element is designed in such a way that it extends up into the third compartment 86, as shown by the dashed outline 11-3 in fig. 10. The profile 113 has a concave or curved middle part 115 which corresponds approximately to the inverted wall of the elastomeric element 70 when thumb or finger pressure is applied from the outside. The reason for the arrangement of the raised profile 113 is to avoid the necessity of repeated pumping movements of the elastomeric element 70 to fill the third compartment 86 and start the ejection of liquid. By arranging the concave part 115, the pumping function is not disturbed, and a volume reduction can be achieved in the third compartment 86. - It has been shown that satisfactory pumping action can be achieved with a dome-shaped elastomer element designed as shown. in f ig...8, 9 Pg 10, and made from ethyl vinyl acetate. The dimensions of the tested elastomeric element were as follows: - !

The advantages of a construction where the partition forms a large as opposed to a small acute angle with the surface are (a) the preservation of the longitudinal clearances required for the partition and for the entire elastomeric element, and (b) the obvious ease of shaping (the stuffing ). When the acute angle is small, the partition wall is more difficult to shape, although the aforementioned alternative requires a smaller pressure difference to open the partition wall to allow fluid to flow. In the same way, a small tip angle provides a better seal against back pressure, and allows a larger opening cross-section for a given material configuration compared to a large tip angle. -

Kaci regard to the thickness 'of the 3i:i] living wall, it will be obvious that

the smaller the thickness, the less rigid the partition, whereby a smaller pressure differential is required to open the partition. By reducing the thickness of the partitions, material improvements are also achieved. If the partitions are made thicker, a large pressure difference is required

to influence or open them. Thicker partitions may be beneficial in applications where complete elimination of trickling or seepage (droplet-like flow) in each direction is desired when the partition is closed. The arrangement of thicker, stiffer partitions enables the manufacture of structures where a "threshold" opening pressure differential is required. In other words, the pressure differential in the "opening" direction must rise above a certain minimum or "threshold" value for the partition wall to be raised from the surface and allow fluid strbm-

ning. -

It should be pointed out that it is advantageous to place the partition walls as far away as possible from the place where the pressure is to be applied to the outer wall of the third or middle compartment. If the partition wall is flush with the outer wall at a location too close to the point of pressure action,

there is a risk that the partition will be twisted (crooked) and possibly move away from the surface when it is not supposed to. -

It will be understood by professionals in the field to which the invention relates

so that the two dividing walls in the pump do not need to be either identical or parallel. Firstly, the acute angles formed between each partition and the surface need not be identical for both partitions. Secondly, it is possible to design the two partitions with different shapes: for example, one can be curved in fig. 7, while the other can be flat as in fig. 3. Thirdly, the lines along which the bottom edges of the partitions touch the surface do not need to be parallel or congruent. For example, the bearing lines for the edges of two flat partitions can form an angle with each other, e.g. a right angle. -

Claims (9)

1. Device for non-return valve and/or pump comprising a preferably one-piece elastomer element (20; 50; 7°) comprising resp. is arranged to cooperate with a bottom element (11; 38; 75) with a surface (1>+; M+; ?k) and through which two openings (12, 13; M>, Mo; 88, 90) out, which elastomer element (20; 50; 70) comprises a retracted part (22; 51; 7D) with a peripheral edge (23; 77) adapted to seal the retracted part (22; 51; 7D) against said flat (1^-; M+; ?h) to together with this form a closed chamber (2<*>+) which communicates with the two openings (12, 13.} V5, ^+6; 88, 90), which retracted portion (22; 51; 71) has at least one partition wall (26; 53, 5^; "78, 80) having an edge (28; 6l, 62; 110, 111) adapted to rest springing across and towards said surface (1^; M+; ?k) between the openings 3 so that the partition wall (26) or walls (53, 5^; 78, 8°) divide the chamber into two or more compartments (30 , 32), two of which communicate with each opening (12, 13; ^5, Vo; 88, 90), which partition (26) or -walls (53, 5^j 78, 80) form an acute angle with any line in one of the departments (the other department 30 by one partition or the third at two partitions) which is (a) tangent to said surface where it touches the edge, and (b) normal to the edge, characterized in that the partition (26) resp. -the walls (53, 5<*>+j 78, 80) over their entire circumference with the exception of said edge (28; 61, 62; 110, 111) are connected to the elastomer element (20; 50, 70), as the inherent resistance to stretching in the material of the partition resp. -walls will result in said edge (28; 61, 62; 110, 111) resisting movement in the direction of the compartment in which the dividing wall or -the walls form an acute angle with said surface (1M-; ¥f; 7M-). 2. Device according to claim 1, characterized in that said peripheral edge (23; 77) has an integrally formed outwardly directed flange (33; 72), by means of which the elastomeric element (20; 50; 70) can is attached to said bottom element (11; 38; 75). 3. Device according to claim 1 or 2, characterized in that the retracted part (22; 51; 7D) is largely hemispherical. Device according to one of the preceding claims, characterized in that the dividing wall or - the walls are curved away from the section in which said slope angle is acute. 5. Device according to one of the preceding claims, characterized in that imaginary lines of intersection between the partition and imaginary planes parallel to said surface (l^-j hh; Jh) are curved, the centers of curvature for the lines of intersection being on the same side of the partition as the compartment in which angle between the partition and the surface is obtuse. 6. Device according to one of the preceding claims, characterized in that the edge (e.g. 110, 111) of the partition (e.g. 78, 80) slopes in the same direction as the partition itself, thereby forming a knife-edge seal between the two departments. 7. Device according to one of the preceding claims, characterized in that said outwardly directed flange (72) on the circumferential edge of the elastomeric element has a bead (77) formed in one piece and projecting downwards from the underside of the flange. 8.. Device according to one of the preceding claims, where two partitions are arranged, characterized in that one partition curves away from the third compartment and the other partition curves away from the second compartment. 9. Device according to one of the preceding claims, where two dividing walls are arranged, characterized in that imaginary lines of intersection between each dividing wall and imaginary planes parallel to said surface ^h), which is a mainly flat surface, are curved, the centers of curvature for the lines of intersection for the first partition is on the same side of the first partition as the first compartment, and the centers of curvature of the intersection lines for the second partition are on the same side of the second partition as the third compartment.