Abstract:
A one-way valve assembly including an axially extending valve body having an inlet end and an outlet end and with an expandable elastomeric sleeve tightly fitted about the valve body. A cover member encloses the elastomeric sleeve and valve body and presses the sleeve into fluid-tight contact with the valve body at two axially spaced locations. Further, the cover member is fitted tightly onto the valve body adjacent its inlet end. A flowable substance flows from a source through the valve body passing to the outlet and cannot flow back to the source.

Description:
BACKGROUND OF THE INVENTION 
     The present invention is directed to a one-way valve assembly including a valve body with an elastomeric member tightly enclosing and sealed to the valve body so that fluid entering between the elastomeric member and the outside surface of the valve body is prevented from bypassing the normal fluid flow path through the valve. 
     The present invention is an improvement on the one-way valve disclosed in the Gerber patent 4,846,810. In Gerber the elastomeric member is secured to the valve body by O-rings. As indicated in Gerber, it is also possible to secure the elastomeric member to the valve body by various other means such as adhesive material, chemical bonding and the like. 
     In the patent to Pardes, 5,092,855, an improvement on the Gerber patent, an enclosing sleeve is disclosed with inwardly directed protuberances for sealing the elastomeric member to the valve body. In this patent the protuberances exert a radially inwardly directed force for achieving the sealing effect. 
     These known one-way valves, while effective for providing one-way flow and preventing contamination from entering into the fluid being dispensed, have a problem in assembling the parts of the valve in a simple and costeffective manner. 
     SUMMARY OF THE INVENTION 
     Therefore, the primary object of the present invention is to provide a one-way valve which can be assembled in a cost-effective manner. 
     Another primary object is to seal the elastomeric member to the valve body in a simple and effective manner to assure that no fluid can leak past the seal. 
     In accordance with the present invention, the valve assembly consists of three parts, all of which can be formed of recyclable plastic material. 
     The valve assembly is made up of an inner valve body enclosed within a tightly fitting elastomeric member with a cover member enclosing the elastomeric member and pressing it at two different locations into sealed engagement with the outer surface of the valve body. 
     In addition to its sealed engagement with the valve body, the elastomeric member can be provided with a duckbill outlet opening. As a result, any contamination such as air, gases, dusts, dirt and the like are prevented from flowing back into the source of the fluid being dispensed by the duckbill closure at the outlet and by the sealed contact between the elastomeric member and the valve body. 
     The valve body has an inlet end and an outlet end. At one of its inlet end and outlet end the valve body has a radially outwardly directed flange. The valve body extends axially from the flange in a cylindrical form until it approaches the other end where its outside surface tapers inwardly. The elastomeric member has a first end with a radially outwardly extending flange arranged to bear against the flange on the valve body. From the flange the elastomeric member extends axially along and tightly encloses the valve body and terminates at its opposite end. In a preferred embodiment the flange is located at the inlet end and has a duckbill closure at the outlet end. 
     To complete the valve, a cover member is fitted over the valve body and the elastomeric member and fits tightly against a radially outer surface of the flange at the inlet or outlet end of the valve body. Adjacent the valve body flange, the inner surface of the cover member has an annular shoulder extending transversely of the axial direction of the valve which presses the flange on the elastomeric member into fluid tight sealed contact with the flange on the valve body. Near the opposite end of the valve body, the interior surface of the cover member has an inwardly directed section, such as an outwardly tapering section, which presses the elastomeric member in fluid tight sealed contact with the correspondingly shaped surface of the valve body. 
     Between the two axially spaced locations where the cover member presses the elastomeric member into sealed contact with the valve body, the inside surface of the cover member is spaced radially outwardly from the elastomeric member. As a result, the annular space within the cover member encircling the elastomeric member provides for radial expansion of the elastomeric member between its two sealed locations with the valve body. 
     Preferably, the valve assembly is mounted on or in an outlet opening from a fluid source, such as a collapsible container. The valve is secured to the source so that there is no possibility of fluid leaking around the valve or contamination entering into the source at the connection between the valve and the source. 
     The valve body has an inlet passageway extending from its inlet end to a location opening from the valve body to the inside surface of the elastomeric member. At a location spaced from the inlet passageway there is an outlet passageway opening through the valve body to the inside surface of the elastomeric member. The outlet passageway extends to the outlet end of the valve body. In a preferred embodiment, the outlet end of the valve body can have a duckbill closure aligned with the outlet. Accordingly, when fluid within the source is pressed into the inlet passageway it causes the elastomeric member to expand outwardly into the annular space between the cover member and the inside surface of the elastomeric member. The fluid then flows within the elastomeric member around the outside surface of the valve body into the outlet passageway and finally through the duckbill closure if one is used. When the force causing the elastomeric member to expand radially is discontinued, the elastomeric member returns to its tightly fitting condition about the valve body preventing flow out of the source and preventing any backflow of the fluid through the outlet passage. As a result, no contamination from the ambient atmosphere can enter through the one-way valve into the source. 
     Initially, at the location where it is sealed to the valve body, the elastomeric member has an increased thickness, that is, at the flange adjacent the inlet or outlet end of the valve body and in the tapered section adjacent the opposite end of the valve body. The increased thickness along with the pressure exerted by the cover member when it is press-fit, snap-fit or welded to the valve body assures that a complete seal is provided. 
     The elastomeric member can be easily produced by molding and it is possible to use multi-cavity molds even in injection molding of thermoplastic elastomeric materials. A slight draft angle in the range of 2°-10° on the side of the elastomeric sleeve allows for a very fast cycle time in molding the member, however, the elastomeric member can be formed without a draft angle. Due to the flange arrangement on both the valve body and the elastomeric member and the complementary annular shoulder on the cover member, it is possible to automate, at very high speed, the assembly of the elastomeric member and the cover member on the valve body. 
     As distinguished from the sealing effect achieved in the Gerber and the Pardes patents, in the present invention the pressing direction is uni-directional in the axial direction and not in the radial direction or bi-directional in the axial direction and, as a result, has been found to afford a much more effective and long-lasting seal. 
     By varying the number, size and configuration of the inlet and outlet passageways through the valve body it is possible to dispense all kinds of fluid media from a low viscous fluid such as water to a very thick or high viscous fluid such as pasta sauces, salsa and the like. 
     Moreover, different flow rates can be achieved from a single drop to one fluid ounce per second. 
     In addition, the inlet and outlet passageways can be formed in a simple manner so that the cost of producing the valve body is kept low while the flow of the fluid through the valve body is enhanced. 
     The elastomeric member can be formed of a thermoplastic or thermosetting plastics material with a durometer of 70(A) maximum. Preferably, the durometer is in the range of 25-55(A). 
     The thickness dimensions of the different sections of the elastomeric member are selected, in combination with the dimensions of the valve body and the cover member, so that the completely assembled valve assures that adequate sealing action is achieved. 
     To assure the retention of the cover member in position for maintaining the sealed contact between the elastomeric member and the valve body, the cover member, in its final assembled position, is secured to the valve body by a press fit, snap fit, ultrasonic welding or some similar connection. 
     Depending on the fluid substance to be dispensed, the flow path of the substance between the valve body and the inside surface of the elastomeric member can be facilitated by shaping the surface of the valve body, such as by a helical groove or the like. 
     The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     In the drawing: 
     FIG. 1 is an axially extending sectional view of a one-way valve assembly embodying the present invention; 
     FIG. 1A is a partial axially extending cross-sectional view of the elastomeric member; 
     FIG. 1B is a partial axially extending cross-sectional view of the valve body; 
     FIG. 2 is a bottom view of the valve body illustrated in FIG. 1; 
     FIG. 3 is an elevational view of the elastomeric member shown in FIG. 1 and turned through 90 relative to FIG. 1; 
     FIG. 4 is an axially extending sectional view of another valve body embodying the present invention illustrating different flow paths for the fluid through the valve body; 
     FIGS. 5A and 5B are an axially extending sectional view and an elevational view, respectively, of another embodiment of the valve body; 
     FIGS. 6A and 6B are views similar to FIGS. 5A and 5B showing still another embodiment of the valve body incorporating the present invention; 
     FIG. 7 is an elevational view of a further embodiment of the valve body; 
     FIGS. 7A, 7B and 7C are inlet end views of the valve body displayed in FIG. 7 illustrating different cross-sectional shapes of the flow passageway; 
     FIG. 8 is an axially extending sectional view of a valve body embodying the present invention having a reduced axial length as compared to the other valve bodies; 
     FIG. 9A is an elevational view of still another embodiment of the valve body; 
     FIG. 9B is an inlet end view of the valve body shown in FIG. 9A; 
     FIG. 10A is a schematic view of a further embodiment of the one-way valve assembly of the present invention; and 
     FIG. 10B is an inlet end view of a part of the one-way valve displayed in FIG. 10A. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In FIG. 1 a one-way valve assembly 10 is illustrated made up of three separate parts, a valve body 12, an elastomeric member 14 and a cover member 16. Both the valve body 12 and the cover member 16 are rigid plastic material parts. The elastomeric member 14, however, is an expandable and compressible part. The three parts can be formed of recyclable plastics materials. 
     The valve body has an inlet end 18 and an outlet end 20. An axis A extends through the valve assembly from the inlet end 18 to the outlet end 20. Starting at the inlet end 18, the valve body has a radially outwardly extending flange 22 followed in the axial direction by a cylindrically-shaped section 24. At the end of the cylindrical section 24 closer to the outlet end 20 the outside surface of the valve body has an inwardly tapered section 26 ending at the outlet end 20. In place of the tapered section 26 the end of the valve body can be perpendicular to or at least transversely of the axis A. 
     An inlet passageway 28 extends axially from the inlet end 18 to a point spaced closely axially from the flange 22 with the inlet passageway opening through the surface of the cylindrical section 24. Spaced axially toward the outlet end 20 is an outlet passageway 30 extending from the outside surface of the cylindrical section 24 to the outlet end 20 of the valve body. The inlet passageway 28 and the outlet passageway 30 are spaced angularly apart about the valve assembly axis A. 
     The elastomeric member 14 is fitted tightly about the cylindrical section 24 of the valve body. As shown in FIG. 3, the elastomeric member 14 has a radially outwardly extending flange section 32. From the flange section 32 the elastomeric member extends axially and has a cylindrical section 34 similar to the cylindrical section 24 of the valve body. At its upper end as viewed in FIG. 3, the elastomeric member has an inwardly tapering section 36 terminating in an end section 38 extending transversely of the valve axis. Extending upwardly from the end section is a duckbill closure 40. Initially at least, the flange section 32 and the tapering section 36 each have an increased thickness T, t, respectively, relative to the thickness S of the cylindrical section 24 for assuring an adequate sealing action in the completely assembled valve. 
     In FIG. 1A the elastomeric member 14 is shown in cross-section. The arrows indicate the direction of the pressing force of the cover member 16 against the flange 22 and the tapered section 26. The pressing force acts unidirectionally and not in two opposite directions. The original inside diameter φ d of the elastomeric member 14 is less than the outside diameter φ D of valve body 12, note FIG. 1B, so that the elastomeric member is stretched tightly on the valve body during the assembly operation. 
     Enclosing the valve body 12 and the elastomeric member 14 is the cover member 16. Cover member 16 has an inlet end 42 and an outlet end 44. From its inlet end 42, the cover member has an increased inside diameter section 46 encircling the flange section 22 of the valve body. At the upper end of the increased diameter section 46 the cover member has a radially inwardly extending shoulder 48. Above the shoulder 48, the cover member has a cylindrical section 50 with a larger inside diameter than the outside diameter of the elastomeric member 14. At the upper end of section 50 the inside surface of the cover member has an inwardly tapering section 52 terminating in an outlet opening 54 encircling the duckbill closure 40. The outlet end 44 of the cover member 16 extends transversely of the axial direction of the valve. The outside surface 56 of the cover member 16 is cylindrical between the inlet end 42 and the outlet end 44. 
     In the assembly of the one-way valve 10, the elastomeric member 14 is fitted downwardly over the valve body 12 so that its flange section 32 rests against the upper surface of the flange section 22 of the valve body. Because the inside diameter of the elastomeric member 14 has a smaller diameter d than the diameter D of the valve body in its cylindrical section 24, the elastomeric member is stretched and fits tightly over the valve body. As a result of this tight fit, the elastomeric member forms a closure of the downstream end of the inlet passageway 28 and the upstream end of the outlet passageway 30. 
     The elastomeric member 14 can be formed in an injection molding operation. The cylindrical section 34 of the elastomeric member can be provided with a slight draft angle in the range of 2°-10° to expedite the molding cycle time. 
     When the cover member 16 is placed downwardly, as viewed in FIG. 1, over the elastomeric member 14 and the valve body 12 it is pressed downwardly until its inlet end 42 and the inlet end 18 of the valve body are in a common plane. In this position the cover member can be tightly fitted to the flange section 22 of the valve body 14 by a press fit, snap fit by ultrasonic welding or some similar connecting operation. This operation provides an effective, reliable mechanical joint. 
     As the cover member is pressed downwardly its shoulder 48 compresses the flange section 32 of the elastomeric member 14 and provides a fluid-tight seal between the flange of the elastomeric member and the flange of the valve body. At the same time, the tapered section 38 of the elastomeric member 14 at the upper end of the valve assembly 10 is pressed against the surface of the inwardly tapered section 26 of the valve body by the correspondingly inwardly tapering surface of the tapered section 52 of the cover member 16. As a result, a fluid-tight seal is provided between the section 38 of the elastomeric member and the tapered section 26 of the valve body 12. Accordingly, at the opposite ends of the cylindrical section 24 of the valve body the elastomeric member 14 is in fluid tight sealed contact with the valve body. 
     Since the inside surface of the cylindrical section 56 of the cover member 16 is spaced outwardly from the outside surface of the elastomeric member 14, an axially extending annular space 58 is provided around he cylindrical section 34 of the elastomeric member 14. A vent opening 60 extends from the annular space 58 to the exterior of the cover member 16. 
     When the one-way valve assembly 10 is secured to a source such as a collapsible container or flexible container, and fluid is pressed out of the container it flows through the inlet passageway 28 and causes the expandable elastomeric member 14 to move radially outwardly within the space defined outwardly by the inner surface of the cover member 16. The fluid passes from the inlet passageway 28 between the outside surface of the valve body and the inside surface of the elastomeric member until it reaches the outlet passageway 30 and flows out of the valve assembly through the duckbill closure 40 within the outlet opening 54. When the fluid is no longer pressed out of the container, the elastomeric member 14 again moves into tightly fitting contact with the cylindrical section 24 of the valve body and closes off the downstream end of the inlet passageway 28 and the upstream end of the outlet passageway 30. Accordingly, the combination of the duckbill closure 40 and the elastomeric member 14 blocks any backflow into the container and also assure that contaminants cannot flow through the one-way valve back into the container. 
     The one-way valve assembly 10 can be used with a great variety of fluid substances ranging from low viscosity fluids, such as water, to high viscosity fluids, such as condiments and pastes. The dimensions of the various parts of the one-way valve and particularly of the elastomeric member 14 are established based on the type of fluid substance to be dispensed through the valve. Generally, the durometer of the elastomeric material forming the member 14 is in the range of 25-55(A). 
     The duckbill closure 40 is dimensioned to open when fluid is pressed out of the one-way valve 10 and to rebound into a closed condition when the fluid is no longer being pressed out of the valve. 
     In FIG. 4 a valve body 112 is illustrated, similar to that in FIGS. 1-3, however, the arrangement of the inlet passageway 128 and the outlet passageway 130 is different. In FIG. 1 the inlet passageway 28 extends axially and the outlet passageway is generally right angled. In FIG. 4, however, the inlet passageway 128 and the outlet passageway 130 extend at an angle to the axis, generally at about a 45. angle, though other angles could be used. This arrangement simplifies the formation of the passageways, particularly the outlet passageway 130. 
     In FIGS. 5A and 5B another arrangement of the passageways through the valve body 212 is shown. The inlet passageway 228 is set at an angle to the axis and the outlet passageway 230 is set at approximately the same angle as the tapered surface so that the elastomeric member, not shown, where it is sealed by the cover member to the valve body. The elastomeric member forms a cover for the passageway 230. In FIG. 5B the location of the outlet passageway 230 is shown in full lines and the location of the inlet passageway 228 is shown in dashed lines. While one inlet passageway 228 and one outlet passageway is shown, a number of each could be used. 
     The ratio of the diameter of the valve body M to the axial length L of the valve body between the flange 222 and the outlet end 220 can be in a the ratio of 0.25 to 3.0. Again, these dimensions depend on the material to be dispensed and the characteristics or durometer of the elastomeric member. 
     In FIGS. 6A and 6B still another valve body 312 is shown where the inlet passageway extends axially for little more than the axial length of the flange 322 and continues as a crossbore extending approximately perpendicularly to the axis. At the opposite end of the valve body 312 four outlet passageways 330 are arranged each about 90° apart and formed similar to that in FIG. 5A where the elastomeric member, not shown, forms a cover for the outlet passageway. This arrangement increases the flow of the fluid out of the valve. 
     In FIG. 7 yet another embodiment of the valve body 412 is displayed with the inlet passageway shown in dashed lines, offset from the axis of the valve assembly. Unlike the other valve bodies shown, valve body 412 has an inwardly tapering section 460 between the flange section 422 and the cylindrical section. As a result, the downstream end of the inlet passageway 428 is located in the inwardly tapering section 460. The outlet passageway 430 is similar to the outlet passageway 230 in FIG. 5A. This valve body 412 shows an alternate arrangement for the inlet and outlet passageways. 
     In FIGS. 7A, 7B and 7C different cross-sectional shapes of the inlet passageway 428 are shown. In FIG. 7A the cross-section 428a of the inlet passageway 428 is circular while in FIG. 7B the cross-section 428b is kidney-shaped and in FIG. 7C the cross-section 428c is oval-shaped. These shapes are based upon the type of fluid being dispensed through the one-way valve assembly. In one embodiment a combination of the different shapes could be used. 
     In FIG. 8, the valve body 512 is shorter in the axial direction than the other valve bodies, though it has the same general surface features. The inlet passageways 528 are located at the radially outer part of the main body of the valve body, that is, immediately inward of the flange section 522. The outlet passageways are similar to those shown in FIG. 5A. With the multiple inlet passageways 528 and outlet passageways 530, the amount of fluid passed through the one-way valve assembly can be increased. 
     In FIGS. 9A and 9B another valve body 612 is displayed with the cover member 616 forming a recess to receive the elastomeric member 614 to provide a passageway 670 extending angularly upwardly and around half of the valve body, note FIG. 9B. When the fluid is pressed out of the container, not shown, it enters the passageway 670 and flows to the outlet end of the valve body. 
     In FIGS. 10A and 10B another embodiment of the valve assembly shown in FIG. 1 is illustrated. The cover member 716 is shown schematically and forms a recess to receive the elastomeric member 714. The inlet passageway 728 extends axially from the inlet end 718 of the valve body just inwardly from the flange section 722. As the fluid expands the elastomeric member 714 with the recess in the cover member 716, it flows into a passageway extending in a helical fashion around the surface of the valve body 712. Opposite the inlet the recess extends along the axial length of the valve body 712 to the outlet passageway 730. The flow out of the valve body through the outlet passageway 730 is similar to that as shown in FIG. 5A. This embodiment affords ease of manipulation and assures that the fluid being dispensed is forced along the valve body 712. 
     The individual parts of the one-way valve assembly can be easily produced and then assembled in a simple and cost-effective manner. The sealing action afforded by pressing the cover member onto the flange end of the valve body and securing the two parts together in a sealed manner assures that during the useful lifetime the valve operates effectively and without any possibility of contamination entering from the outlet back through the valve body into the source of the fluid being dispensed. 
     While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.