Bite valve for personal hydration devices and a method for making the same

Abstract

A diaphragm (12) for use with a fluid carrying condiuit (70) or outer body (14) where the diaphragm (12) has a convex outer surface (26), a concave inner surface (28), a slit (32) extending from surface (26) to surface (28), and a notch defined by two walls (40, 42) at outer surface (26). The walls (40, 42) preferably diverge towards the outlet end (20) so that upon deflection of diaphragm (12), a greater minimum gap (46) for fluid movement is created when compared to the minimum gap (48) of a diaphragm not having the notch. The notch may have a cross section shape of a “V”, a “U”, or a three section rectilinear form, and may be formed at either surface depending upon the direction of diaphragm deflection.

Description

BACKGROUND OF THE INVENTION

[0002] Flexible liquid container systems are extensively used in recreational and sporting activities for carrying supplies of water or other nourishing fluids often referred to as sport-drinks. Such systems may be adapted to be carried by someone engaged in sporting activities such as cycling or mountain climbing, and are often used by these persons to drink liquids without pausing from the activities in which they are engaged.

[0003] An important component of a flexible liquid container system, particularly a system that is used during a sporting activity, is a valve that permits a user to rapidly ingest large volumes of liquid, while also providing a liquid tight seal for the container while not in use. To achieve these objectives, a commonly used system provides for a flexible container, a tube partially disposed in the container and extending therefrom, and a bit valve positioned on the exposed end of the tube.

[0004] A relatively simple bit valve for such a system is disclosed in U.S. Pat. No. 5,085,349. The valve has a body in the form of a tube having two flattened (opposite) sides, thus approximating a flattened ellipse, and having inlet and outlet ends. A diaphragm valve proximate the outlet end of the tube has a slit formed therein, extending generally along the minor axis of the ellipse. A user operates the valve by compressing the flattened sides of the tube together, thereby distorting the diaphragm and opening the slit to allow liquid to be expelled, typically by sucking into the user's mouth.

[0005] While clearly a simple arrangement, because it has no moving parts, this valve has certain shortcomings, particularly restricted flow rates and excessive weeping and dribbling. The flot rate of liquid through the valve is dependent upon the geometry of the slit and is restricted by two particular factors: the length of the slit and the shape of the slit mating surfaces. The size of the orifice created when the valve is actuated, and thereofre the flow rate, is directly related to the length of the slit. The shorter the slit, the lesser the flow rate. Although a longer slit will obviously increase flow rates, it also will weaken the integrity of the seal and allow more weeping and dribbling.

[0006] In addition to the length of the slit, the shape of the slit mating surfaces impacts the size of the orifice under actuation. The leading edges of the slit, typically defined as those on the outlet surface of the valve if it deflects towards the fluid source, will determine the orifice boundaries and therefore the flow rate when actuated. Thus, smooth and square mating surfaces descrease the flow rate. However, if the surfaces do not squarely mate with each other, the integrity of the seal will be weakened and more weeping and dribbling will occur.

[0007] Weeping and dribbling of liquid through the valve when not in use result at least in depletion of liquid resources for the user and also a gradual loss of valve integrity, not to mention the possibility of collateral damage to surrounding goods such as clothes. In the prior art, two particular means have been used to control weeping and dribbling: making the diaphragm concave/convex with the convex side oriented toward the inlet end of the valve, and making the diaphragm thicker so as to provide both greater contact area between the slit mating surfaces and a greater restoring force to the diaphragm to bias the slit towards the closed position following actuation of the valve.

[0008] Although increasing the thickness of the diaphragm, at least in the central area of the diaphragm surrounding the slit, serves to help reduce weeping and dribbling, this increase thickness often requires greater physical force be applied by a user to operate the valve and open the slit.

[0009] Furthermore, although the convex inner surface of the diaphragm acts as a self-energizing seal (i.e., when placed under pressure if forces the slit mating surfaces together and prevents leaking), under very low hydrostatic pressures fluid can weep past the diaphragm, particularly after a high number of cycles has caused the material of the valve to lose some of its resiliency. Moreover, the liquid container may become pressurized, or the container may be raised above the outlet to create a hydrostatie pressure head, thus generating the expelling force for the liquid through the valve. However, the contents of the liquid container are often not under any pressure at all, and therefore the sealing characteristics of this type of diaphragm are greatly reduced, if not eliminated entirely.

SUMMARY OF THE INVENTION

[0010] The present invention relates to a bite valve including a diaphragm portion and to a diaphragm for use with liquid containers using a fluid delivery conduit. As used herein, a diaphragm portion or diaphragm refers to a generally disc-shaped structure having two major opposing surfaces and a perimeter establishing a sectional thickness. A feature of the invention is the incorporation of beveled or chamfered edges in a slit extending from one major surface to the other major surface. The design maximizes flow rates, and minimizes weeping and dribbling when compared to conventional diaphragms of the prior art. Moreover, the diaphragm portion or the diaphragm may be planar or convex/concave wherein the convex surface may either be positioned towards or away from the ultimate source of fluid.

[0011] The valve preferably comprises a cylinder portion and a diaphragm portion, although as noted above only a diaphragm is needed. If a cylinder portion is used, it may be circular in cross section, or have a cross section of other geometric forms such as generally elliptical. Preferably, the cylinder portion hs an inner surface, an outer surface, a first end at a first perimeter, and a second end at a second perimeter wherein the first end is preferably adapted to fit the fluid delivery conduit.

[0012] The diaphragm portion is coextensive with the second perimeter to prevent fluid entering the first end from exiting the second end. The diaphragm portion has a first surface, a second surface, and a perimeter coincident with the second perimeter. As noted previously, the cylinder portion is intended to provide the means by which the diaphragm is located on the fluid conduit or tube. It is contemplated that the diaphragm can also be directly located in the tube. In such a situation, the diaphragm becomes an insertable disc having a geometric cross section at least approximating that of the tube in which it is to be inserted.

[0013] Formed in either the diaphragm portion or diaphragm is an elongate slit defined by a first inner wall and second inner wall of the diaphragm wherein at least a portion of the first and second inner walls diverge towards the surface of the diaphragm undergoing flexion when compressed in the slit axis. This geometry thereby creates a notch or trough when the diaphragm portion or diaphragm is in the relaxed state. The creation of a notch or trough operates to maximize the orifice through which fluid will flow when the diaphragm is compressed along the slit axis to create a gap, while retaining sufficient material to maintain an effective sealing arrangement when in the relaxed state.

[0014] Variations of the invention include multiple slits wherein at least one slit includes a notch or trough; positioning the convex side of the diaphragm or diaphragm portion towards the upstream end of the conduit where the inner wall divergence is either towards the upstream or downstream end; positioning the concave side of the diaphragm or diaphragm portion towards the upstream end of the conduit where the inner wall divergence is either towards the upstream or downstream end; and the cross sectional profile of the notch or trough is one of a “V” shape, a “U” shape or a rectilinear “” shape.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG. 1 is a cross section view of a bite valve assembly incorporating the present invention taken along the longitudinal axis and orthogonal to a slit in a diaphragm;

[0016] FIG. 1 a is a cross section view of an alternative embodiment of the invention wherein a diaphragm is directly insertable into a fluid conduit and a cap is employed to retain the diaphragm therein;

[0017] FIG. 2 is a cross section view of the inner body, showing the details of the diaphragm;

[0018] FIG. 3 is a plan view of the inner body, showing the slit located along the minor axis of an elliptical diaphragm with chamfered or beveled edges thus forming a notch or trough;

[0019] FIG. 4 is a cross section view of the outer body, showing the plug and sleeve;

[0020] FIG. 5 a is a cross section view of the of the inner body, illustrating an increased fluid orifice when beveled or chamfered edges are employed regarding the slit;

[0021] FIG. 5 b is a plan view of the inner body of FIG. 5a, showing the area of the orifice of the actuated valve;

[0022] FIG. 6 a is a cross section view of the inner body of a prior art diaphragm design, illustrating a fluid flow constriction at the downstream end of the slit; and

[0023] FIG. 6 b is a plan view of the inner body of FIG. 6a, showing area of the orifice of the actuated valve.

DETAILED DESCRIPTION OF THE INVENTION

[0024] Referring to the several Figures wherein like numerals indicate like parts, and more particularly to FIG. 1, a preferred embodiment of bite valve 10 is shown in cross section. Bite valve assembly 10 comprises resilient, elastomeric inner body 12 and resilient, elastomeric outer body 14, which are positioned co-axially with respect to each other such that inner body 12 is substantially surrounded by outer body 14, and both bodies 12 and 14 share longitudinal axis 16. Preferably, at least inner body 12 is constructed from liquid reaction injection molded silicone having a 45 to 55 A scale durometer hardness. Assembled bite valve assembly 10 thus has inlet end 18 to receive a fluid conduit or tube, and outlet end 20. The interference fits between the two bodies 12 and 14 serve to lock and retain valve assembly 10 in the correct configuration while in use, but also provides for a convenient means to replace inner body 12, which may become worn through use.

[0025] Also shown in FIG. 1 is circumferential lip 58 positioned generally radially outward from the active portion of inner body 12. Lip 58 creates an enhanced area of localized resiliency to increase the restoring force present at the active portion of inner body 12, and decreases wear on diaphragm 22.

[0026] An alternative form of the invention is shown in FIG. 1A. Instead of incorporating a cylinder portion to engage with outer body 14, only diaphragm 22′ is present. Tube 70 is modified to receive diaphragm 22′ and retention memeber or cap 80 frictionally fits over tube 70 to prevent unintentional escapement of diaphragm 22′.

[0027] The cross section view of inner body 12 in FIG. 2 and the plan view thereof in FIG. 3 show in greater detail the nature of slit 32. Inner body 12 has cylinder portion 24 and diaphragm portion 22. Cylinder portion 24 has a generally elliptical section, a smooth outer wall, and a pair of circumferential ribs 38. these ribs are formed to locate in corresponding complementary grooves 54 formed in outer body 14 as is best shown in FIG. 4. Diaphragm 22 has concave major surface 26 polypeptide [SEQ ID NO: 2]. of diaphragm 22 to receive complementary circumferential rib 52 as is best shown 3], β-secretase (1fkn) [SEQ ID NO: 4], progastricsin (1htr) [SEQ ID NO: 5] and pepsinogen (3 pgs) [SEQ ID NO: 6]. The lines indicate the residue pair involved in forming disulfide bond as observed in 1fkn. The codes representing the conserved residues at the active site for the aspartyl protease family are residues 93-95 and residues 289-291 for pbsz, residues 9193 and residues 274-276 for 3psg, and residues 91-93 and residues 276-278 for 1htr. The signal peptide segments (residues 1-21 for pbsz, residues 1-16 for 1 htr, and residues 1-15 for 3 psg) were not included for the alignment operation because they will be cleaved off by signal peptidase during the secretory process. walls 40 and 42 for reasons that will now be described.

[0028] The incorporation of diverging walls 40 and 42 to form a chamfer, bevel, notch or trough is intended to increase the volumetric flow of fluids during fluid expulsion actions. Turning to FIGS. 5A, 5B, 6A, and 6B, it can be seen that for a given upstream gap 44, the minimum gap through which fluids must pass is greater with respect to a diaphragm incorporating the invention, i.e., gap 46 as compared to a diaphragm not incorporating the invention, i.e., gap 48. Thus, by reducing the degree of gap constriction by removing diaphragm material (or equivalently failing to introduce material) present at the side of diaphragm flexion, regardless of fluid flow direction, an increased area through which fluid may flow is created. Naturally, by removing material at this point to chamfer or notch the slit, the total area of contact between the slit boundaries is necessarily reduced, thus affecting weeping and dribbling properties. Thus, a suitable sealing interface must be maintained, for example at least 30% of the sectional thickness of the diaphragm at the slit.

[0029] Methods for creating the valve or the diaphragm include injection molding the piece having the slit and notch preformed therein, or injection molding the piece and subsequently creating the slit and removing material adjacent to the slit to form the notch.

[0030] The following data describes the effect of modifying a prior art bite valve to incorporate the invention without encountering undesirable weeping and/or dribbling. To obtain the data, 15 standard slit bite valves were used; five were left unmodified for control, five were modified to remove material adjacent the downstream side of the slit by means of a sharpened blade, and five were modified to remove material adjacent the upstream side of the slit by means of a grinding tool. Chamfer or bevel angles relative to centerline ranged from about 30 to 45 degrees. Also tested, although not pertinent to the invention, was the effect of different fittings to connect the assembly to a fluid tube. In all tests, a 127 cm water column and reservoir was used to supply water under pressure to the valve assembly, and the minor axis of the assembly measured about 9.53 mm. The depth of material removal was generally limited to no more than 50% of the diaphragm thickness. Thus, for 80 mil. polyurethane material having a durometer value of 40-50, approximately 30-50 mil. remained for creating a seal at the gap after material removal.

			Flowrate	Flowrate (cc/	Flow loss
		Slit	(cc/min)	min) with-	due to
	Sample	Length	WI barbed	out barbed	barbed fit-
	No.	(mm)	fitting	fitting	ting (cc/min)
Beveled	1	6.81	1850	2150	300
edge-razor	2	6.99	1750	2000	250
cut	3	6.99	2000	2350	350
	4	6.13	1800	2100	300
	5	6.81	1800	2100	300
	Avg.	6.86	1840	2140	300
	Std. Dev.	0.127	96	129	35
Beveled	6	6.81	1900	2150	250
edge-tool	7	7.06	1950	2250	300
ground	8	6.93	1900	2200	300
	9	6.99	1950	2250	300
	10	6.81	1850	2150	300
	Avg.	6.91	1910	2200	290
	Std. Dev.	0.102	42	50	22
Prior art	11	7.06	1350	1450	100
bite valve	12	7.09	1350	1500	150
	13	6.76	1300	1450	150
	14	6.65	1250	1350	100
	15	6.99	1350	1450	100
	Avg.	6.91	1320	1440	120
	Std. Dev.	0.203	45	55	27

Claims

1. A valve for use with a fluid carrying conduit comprising: a cylinder portion having an inner surface, an outer surface, a first end at a first perimeter, and a second end at a second perimeter wherein the first end is adapted to fit the conduit; a diaphragm portion coextensive with the second perimeter to prevent fluid entering the first end from exiting the second end, the diaphragm portion having a first major surface, a second major surface, and a diaphragm perimeter generally coincident with the cylinder portion second perimeter; and an elongate slit extending from the first major surface of the diaphragm portion through to the second major surface of the diaphragm portion and defined by a first wall and second wall of the diaphragm portion wherein at least a portion of the first wall and the second wall diverge towards the second major surface of the diaphragm to define a notch in the second surface of the diaphragm at the slit when the diaphragm portion is in a relaxed state.

2. The valve of claim 1 wherein the cylinder has a circular cross section.

3. The valve of claim 1 wherein the cylinder has a generally elliptical cross section.

4. The valve of claim 1 wherein there is only one slit.

5. The valve of claim 1 wherein the slit is linear.

6. The valve of claim 1 wherein the notch has a cross section shape from the group consisting of a “V” shape, a “U” shape, and a three section rectilinear “” form shape.

7. The valve of claim 1 wherein the notch extends between 1% and 70% of the sectional thickness of the diaphragm portion.

8. The valve of claim 1 wherein the second major surface of the diaphragm portion undergoes flexion when the slit is compressed along its axis.

9. The valve of claim 1 wherein the first major surface of the diaphragm portion is convex.

10. The valve of claim 1 wherein the first major surface of the diaphragm portion is concave.

11. A diaphragm having a first major surface, a second major surface, and a perimeter bounding the first and second major surfaces, the diaphragm being for use with a fluid carrying conduit having a first end, a second end and an inner diameter sufficient to receive the diaphragm, whether compressed or not, and comprising: an elongate slit extending from the first major surface of the diaphragm portion through to the second major surface of the diaphragm portion and defined by a first wall and a second wall of the diaphragm wherein at least a portion of the first wall and the second wall diverge towards the second major surface of the diaphragm so as to create a notch in the second surface of the diaphragm at the slit when the diaphragm portion is in a relaxed state.

12. The diaphragm of claim 11 wherein the cylinder has a circular cross section.

13. The diaphragm of claim 11 wherein the cylinder has a generally elliptical cross section.

14. The diaphragm of claim 11 wherein the first major surface and the second major surface are generally parallel to one another and are planar.

15. The diaphragm of claim 11 wherein the first major surface and the second major surface are generally parallel to one another and are non-planar.

16. The diaphragm of claim 15 wherein the first major surface is convex and the second major surface is concave.

17. The diaphragm of claim 15 wherein the first major surface is concave and the second major surface is convex.

18. The diaphragm of claim 11 wherein the maximum external diameter of the perimeter is generally equal to or less than the maximum internal diameter of the conduit.

19. The diaphragm of claim 11 wherein the notch has a cross section shape selected from the group consisting of a “V” shape, a “U” shape, and a three section rectilinear “” form shape.

20. The diaphragm of claim 11 wherein the notch does not extend more than 70% of the sectional thickness of the diaphragm as determined from the first major surface to the second major surface.

21. The diaphragm of claim 11 wherein there is only one slit.

22. The diaphragm of claim 11 wherein the second major surface of the diaphragm undergoes flexion when the slit is compressed along its axis.

23. The diaphragm of claim 11 wherein the first major surface of the diaphragm undergoes flexion when the slit is compressed along its axis.