MXPA99011651A - Duckbill valve - Google Patents

Abstract

A duckbill valve is provided which includes a hollow cylindrical elastomeric body (2) with first (4) and second (6) ends. The first end (4) has walls (8) parabolically tapering to an elongate slit (10), the slit being surrounded by an upper and lower lip (12). The second end (6) has a non-uniformly round (e.g. oval) outer wall terminating in an open mouth. When inserted into a perfectly round apertured fitting, the non-uniformly round outer walled elastomeric body is bowed to form-fit the round configuration thereby forcing shut the lips and slit. Upon increased air pressure within the elastomeric body, the slit is forced open. In a further embodiment, the inner wall of the second end may be non-uniformly (e.g. oval) round. Insertion of a round tubular fitting within the non-round inner wall of the elastomeric body also achieves a bowed form-fit configuration which forces shut the lips and slit.

Description

CURVED MOUTH VALVE DESCRIPTION OF THE INVENTION The invention is related to a new curved mouth valve with improved performance, and lower manufacturing cost compared to traditional ones. Curved-mouth valves are used to regulate pressure in a host of devices found in many industries. Applications for this device are found in automotive brakes, small appliances, kidney dialysis, hypodermic syringes, sports equipment, toys, non-aerosol pumps and a variety of industrial equipment. Its popularity is based on its simple construction. There are no moving parts present, other than the rubber housing my sms. Despite its simplicity, outdated manufacturing processes have caused the traditional curved valve to be relatively expensive. Standard manufacturing employs the compression molding of a rubber, followed by a second, separate step of cutting a groove inside the molded rubber valve. This two-step procedure decreases the speed of production and adds cost. U.S. Patent 5,010,925 (Atkinson et al.), Assigned to Vernay Laboratories, Inc., describes a more sophisticated version of a curved-mouth valve assembly. In one embodiment (Figure 6), an outer wall of the valve body is dimensioned in an oval shape. The insertion of the oval body to form a circular depression of a valve fitting tilts the flanges 38, 40 flared together to close the valve assembly. Unfortunately, the V-shaped flared walls intersect only at a relatively narrow point of contact. This results in a less than robust seal. German Patent 1,130,232 is related to the curved mouth valve having an opening defined by an oval internal and external wall. It is an object of the present invention to provide a curved mouth valve having a stronger seal. Another object of the present invention is to provide an improved curved mouth valve that can be manufactured in a single process step.

Still another object of the present invention is to provide a curved mouth valve with a less expensive construction. Still another object of the present invention is to provide a curved mouth valve having improved performance and longevity. In a first aspect a curved mouth valve is provided which includes a hollow cylindrical elastomeric body with first and second ends, the first end has parabolic outer walls that are flared to an elongated slot, the second end has an internal and external wall that they end in an open mouth, with at least one of the inner and outer walls of the second end not uniformly rounded. Preferably the internal and / or external non-uniformly rounded walls have a f or rma or al. The elastomeric body preferably includes a cylindrical intermediate section between the first and second ends. Preferably, a collar surrounds the mouth, and exits radially outward from the outer walls of the second end.

In another aspect of the invention, the elongated slot in the open position (as originally molded) has an ovoid shape, somewhat resembling a football. Conveniently, an upper and lower flange surrounds the ovoid groove, with each flange having an octagonal surface to a longitudinal axis running through the curved mouth from the first to the second end. Preferably, the upper and lower flanges in the open position converge towards the pointed, elongated ends of the left and right flanges. Advantageously, the flanges extend substantially through the entire diameter of the first end. By the term "substantially" is meant at least 70%, preferably at least 85%, but optimally at least 95% through the diameter of the first end. Preferably, the parabolic curvature of the flange and groove arrangement allows q-u e when the flanges are tilted together they can couple a relatively large mutual contact surface. With this you can achieve a more hermetic seal. The building materials for the elastomeric cut can comprise, or even consist of an elastomer prepared from the polymerization of a monomer selected from the group consisting essentially of ethylene, propylene, styrene, butadiene, acrylonitrile and mixtures thereof (providing copolymers) . Silicones can also be used as construction material. More preferred is the use of Kraton® rubber. The elastomeric body can be conveniently transparent. The curved mouth valves of the present invention are conveniently formed with a method which includes injecting an elastomer in its liquid state into a mold. The mold must contain surface structures that allow the formation of an open slot within the elastomeric body. After injection, the molded body is ejected from the mold of the injection molding machine. A key advantage of the present invention is that through injection molding, curved-mouth valve bodies can be manufactured with a slot concurrently constructed with other parts of the device. It is no longer necessary to have a second step of cutting the slot. It is also an advantage that typically less material is needed to form the valve body. The new valve allows for thinner walls, and in fact still requires less wall material to operate. In comparison, curved mouth valves of the prior art should have relatively thick or poorly flexible rubber walls to obtain rigidity. Without the rigidity, the old curved mouth valves can not maintain a closed slot. Rigid rubber can not be molded by injection; it is dimensioned by means of compression molding. The curved mouth valves of the present invention according to a first embodiment, in which the outer wall is non-uniformly rounded (eg oval), are intended to be inserted into an accessory having a rounded inner wall against which the outer walls of the intermediate section of the elastomeric body are placed. The interaction between the rounded fixture and the unrounded wall forces the last to obtain a rounded shape, thereby compressing the groove flanges. Under this arrangement, the slot remains closed as long as the atmospheric pressure inside the valve and outside the slot is essentially identical. Any significant increase in pressure within the hollow cylindrical elastomeric body will cause the groove to separate the flanges and open, allowing equalization of pressure between the inner and outer parts of the valve. A further embodiment of this invention is a curved mouth valve having a rounded outer wall, but an inner wall not uniformly rounded (eg, oval). Accordingly, a curved-mouth valve assembly is achieved by inserting an accessory with a rounded outer wall into the hollow cylindrical elastomeric body with internal walls not uniformly rounded (eg, oval). The interaction between the rounded fitting and the non-uniformly rounded inner wall of the curved-mouth valve forces the latter to provide a rounded shape, thereby compressing the groove flanges. As with the previous mode, the slot remains closed while the atmospheric pressure inside the valve and outside the slot is essentially identical. Any significant increase in pressure within the hollow elastomeric body will cause the groove to separate the flanges and open, allowing equalization of pressure between the internal and external parts of the valve. The various objects, features and advantages of the present invention will be explained more fully by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a valve with a curved mouth in the open position according to a first embodiment of the present invention; Figure 2 is a front elevation view of the curved mouth valve according to Figure 1; Figure 3 is a cross-sectional view taken along line 3-3 of Figure 1; Figure 4 is a front elevation view of the curved-mouth valve shown in Figure 1 inserted into an accessory (seen in partial view), wherein the groove is in a closed position; Figure 5 is a cross-sectional view of a shortened version of Figure 1 with the slot in an open position; Figure 6 is a cross-sectional view of the shortened version according to Figure 5 wherein the curved mouth valve has been inserted into an accessory, the groove being in its closed position; Figure 7 is a side elevational view of a second embodiment of the curved-mouth valve according to the present invention; Figure 8 is a cross-sectional view taken along line 8-8 of Figure 7; Figure 9 is a cross-sectional view of Figure 7 in the longitudinal direction where an accessory is inserted into the curved-mouth valve, the slot being in its closed position; and Figure 10 is a cross-sectional view taken along line 10-10 of Figure 9. Figure 1 illustrates a modality of the curved-mouth valve of the present invention. The valve includes a hollow cylindrical elastomer body 2 with a first end 4 and a second end 6. The parabolically flared walls 8 are located near the first end converging towards an elongated slot 10 defined by the flanges 12. The second end of the elastomeric body has an external wall 16 in an oval shape ending in an open mouth 14, defined by a non-circular internal wall 15. A cylindrical intermediate section 18 connects the ends -first and second. A collar 22 is positioned near the second end, and exits radially outward from the outer walls 20 of the intermediate section. Figure 2 better illustrates the flanges 12, which are formed with an upper flange 13 and a lower flange 17. The upper and lower flanges in the open (originally molded) position have an ovoid shape. At the ends 211, 21r of the left and right slot. Figure 3 best illustrates the outer walls of the intermediate region as being a noncircular circumference. In cross section, the walls of the intermediate section have a pair of wider segments 24, separated by the thinner segments 26. The inner and outer wall of the intermediate section therefore defines an oval shape. The major axis 0, I of the respective internal and external walls defines oval shapes that are orthogonal to each other. In other words, the oval shapes on their long axis are perpendicular. For purposes of this invention, it is optional that both the inner and outer wall are not uniformly rounded. Figure 4 illustrates the curved valve having the slot 10 compressed in a closed position which results from the elastomeric body being compressed within a tubular fitting 28 to form a valve assembly. The oval geometry of the elastomeric body is forced into a configuration by the rounded internal walls 30 of the tubular fitting 28. Figure 5 illustrates a shortened version of the embodiment of Figure 1. In this embodiment, the flared walls 8 at a distal end of the slot include a lock projection 32. The intermediate section 18 separates the projection 32 from the collar 22, and provides a depression for receiving the tubular fitting 28. Figure 6 illustrates the elastomeric body of the curved-mouth valve inserted into a perfectly rounded opening of the tubular fitting, the latter buckling the oval walls of the elastomeric body to obtain a seal. As a result, the slot 10 is forced into the closed position. The groove opening only occurs when the pressure inside the curved mouth valve becomes greater than the air pressure outside the groove. Figure 7 illustrates a second embodiment of the present invention. In this embodiment, as best illustrated in Figure 8, the outer walls of the intermediate section have a rounded circumference, while the inner walls are non-circular. In cross section, the walls of the intermediate section have a pair of thicker segments 124 separated by the thinner segments 126. In this way, the intermediate wall of the intermediate section defines an oval shape. Similar to the first embodiment, the curved-mouth valve of Figures 7 and 8 includes an elongated slot 110 surrounded by flanges 112, the latter being formed with an upper flange 113 and a lower flange 117. Figure 9 illustrates the hollow cylindrical elastomeric body 102 of the curved-mouth valve, with a non-circular internal wall 115 sitting on a perfectly rounded tubular fitting 128, the latter bulging the oval internal walls of the elastomeric body 102. As a consequence, the slot 110 is forced into the closed position. Figure 10 illustrates the closed position resulting from the combination of the valve valve assembly of the curved valve and the tubular accessory. The slot opening only happens when the pressure inside the curved valve is greater than the air pressure outside the slot. The tubular fitting 128 can be a rigid plastic tube such as a dip tube inside a liquid dispensing container. Although only two embodiments have been described, those skilled in the art will be able to provide original modifications and adaptations all of which are considered within the spirit and scope of the present invention.

Claims (10)

1. Curved mouth valve comprising a hollow cylindrical elastomer body with first and second ends, the first end has parabolic external walls that are flared towards an elongated slot, the second end has an external and internal wall ending in an open mouth, with at least one of the outer and inner walls of the second end being not uniformly rounded s.

2. Curved mouth valve according to claim 1, wherein the outer wall of the second end is not uniformly rounded and has an oval shape.

3. Curved mouth valve according to the rei indication 1 or claim 2, wherein the inner wall of the second end is not uniformly rounded and has an oval shape.

4. Curved mouth valve according to any of the preceding claims, further comprising a collar that surrounds the mouth, the body further comprises a cylindrical intermediate section between the first and second end, the collar exits radially outwardly from the external walls of the intermediate section.

5. Curved mouth valve according to any of the preceding claims, wherein the elongated slot is bounded by an upper flange and a lower flange dimensioning an oval shape in an open position of the valve.

6. Curved-mouth valve according to claim 5, wherein the upper and lower flanges intersect at the opposite flange ends, the groove extends at least 70% through the diameter of the first end.

7. Curved mouth valve according to any of the preceding claims, wherein the elastomeric body is constructed of an elastomer prepared from the polymerization of a monomer selected from a group consisting essentially of ethylene, propylene, styrene, butadiene, "acrylonitrile and mixtures thereof.

8. Curved mouth valve according to any of the preceding claims, wherein the elastomer body is constructed of silicone.

9. Curved mouth valve according to any of the preceding claims, wherein the elastomer body is transparent.

10. Method for producing the body of the curved valve mouth according to any of the preceding claims comprising: i) injecting an elastomer in its liquid state into a mold, the mold includes surfaces that allow the formation of an elongated slot within the body at one end thereof; and ii) expelling the mold body.