Abstract:
An apparatus comprises a housing having an end with an input having an entrance and an output and a probe integral with the housing extending from the output to beyond the end of the input. The probe has a passageway connected to the output. A spring-biased seal is disposed about the probe to seal the passageway and is depressible by an exterior member to expose the passageway. The extension of the probe beyond the end of the input permits the swabbing thereof before the depression of the seal.

Description:
This is a file wrapper continuation-in-part of application Ser. No. 08/777,081 filed Dec. 30, 1996. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to flow control and, more particularly, to swabbable check valves for the needless control of injected fluids. 
     A valve is a device that regulates flow. A check valve permits flow in one direction only. Where fluids need to be introduced into the body, it is common practice to do so through a check valve connected to a catheter, which is a slender hollow tube inserted into a body passage or cavity for passing fluids. 
     For example, medication can be injected into a check valve connected to a catheter. In prior practice, medication from the syringe has been introduced using a needle, but this can be undesirable, since in modern medical practice, needle sticks are to be avoided. A number of attempts have been made to achieve the introduction of medication without the need for using syringes with needles. 
     Illustrative examples of attempted needless control of injected fluids are disclosed in Newgard et al., U.S. Pat. No. 5,064,416; Sivert, U.S. Pat. No. 4,915,687; Jackson, U.S. Pat. No. 4,429,856; Kilmarx, U.S. Pat. No. 3,352,531 and Faust et al. U.S. Pat. No. 5,116,021. All of these illustrative arrangements have the objection that pathogens can enter their inlets without being easily sterilized. While attempts have been made to maintain sterility by capping the inlets, the requirement of caps presents additional complexity and expense. In addition, caps can become dislodged during storage and handling, rending the devices unusable or requiring special sterilization procedures. 
     Newgard &#39;416 is typical in having a long inlet passage before there is access to a moveable member which is pierceable and controls flow by the extent to which a valving member can be dilated. Sivert, Johnson, Kilmarx and Faust are similarly objectionable. 
     Still another consideration is desire to operate flow control devices with low “cracking” pressures, i.e. the pressure at which a control member moves away from its seat. For such devices, it is desirable to use relatively thin diaphragms. Unfortunately, thin diaphragms pose problems of stability. The diaphragm may move slightly away from its central position and become lodged against a side wall, causing a problem of leakage. 
     The catheters used with check valves are of various types. One type includes a tubular member for the introduction of fluids into a blood channel which may be venous or arterial. Another type is a double-walled flexible tube which terminates at its outer end in two separate branches. One branch continues as an outer tube and terminates at its inner end in a inflatable portion. The other branch continues as an inner tube with a through passage that extends to the inflatable portion of the outer tube. There are various other types of catheters as well. 
     With all types of catheters, it is desirable to be able to control the through flow of fluid using a suitable valve, which can be used in non-catheter applications as well. 
     Accordingly, it is an object of the invention to provide a miniature check valve which can be used without needles and is swabbable by being easily wiped with disinfectant across its inlet to eliminate contamination and pathogens. A related object is to allow the check valve to be readily usable with devices, such as catheters, to control fluid flow while restricting operation by a patient or unauthorized personnel. 
     A further object of the invention is to provide a simple and expendable check valve, which can be mass produced, readily assembled and provide ease of operation. 
     SUMMARY OF THE INVENTION 
     In accomplishing the foregoing and related objects a miniature check valve is provided by a tubular housing having centered at its inlet bore a solid-ended and non-moveable probe surrounded by an annular sealing member so that both the probe and the sealing member can be cleansed by swabbing, i.e., wiping, the inlet end before the annular sealing member is depressed by, for example, the blunt end of a syringe in order to engage an internal passageway of the probe and permit passage of fluid from the syringe through the valve. 
     The sealing member abuts an inwardly facing shoulder or valve seat, and is held in its closed position by, for example, a spring, which can be elastomeric, until the sealing member is disengaged from the valve seat by an external member, such as the hollow blunt end of a syringe containing fluid that is to be injected through the valve, for example, into a catheter. 
     In accordance with a broad aspect of the invention, the housing has an input and output; a probe within the housing extends from the output to beyond the input; the probe has a passageway thereinto connected to the output; and a depressible member seals the input, surrounding the probe and being depressible therealong to expose the passageway. 
     Because of the extension of the probe beyond the input swabbing of the probe is permitted before the depression of the sealing member. 
     The input has an entrance and the sealing means can be substantially flush with the entrance. Where the entrance has a prescribed level, the sealing member can terminate at the prescribed level, or below it. 
     The probe is configured to facilitate contact with an external member, such as a Luer fitting for depressing the sealing member. The probe can terminate in a rounded end beyond the input or in a flattened end. 
     The sealing member seals to the housing and to the probe, and the sealing to probe can be at a plurality of positions therealong. The sealing member can include provision for applying spring force thereto. 
     In a method of the invention the steps include: sealing an input by a depressible member surrounding a probe extending beyond the input; and depressing the member to uncover, in the probe, a passageway connected to an output. As a result, the depression of the member permits flow from the input to the output. 
     The member is depressible from a position substantially flush with the entrance to the input. Where the entrance has a prescribed level, the member is depressible from the prescribed level, or from below the prescribed level. 
     The method further includes the step of contacting the probe by an outside member, such as a Luer termination, for depressing the sealing member. The step of contacting the probe takes place at a rounded end beyond the input, or astride a flattened end beyond the input. 
     The sealing to the probe can be at a plurality of different locations therealong, spring force can be applied to the sealing member. 
     In a method of manufacturing a swabbable check valve the steps include: (a) providing a housing having an input and containing a probe within the housing extending from a output to beyond the input; (b) proving, into the probe, a passageway that is connected to the output; and (c) sealing the input by a member surrounding the probe and depressible therealong to expose the passageway. The extension of the probe beyond the input permits the swabbing thereof before the depression of the sealing member. 
     A miniature check valve in accordance with the invention includes a tubular housing having an outlet and an inlet at a level surrounded by an exterior surface; a bore extending from the exterior surface into the housing; a stationary probe centered at the inlet at the level of the exterior surface, with the probe having an internal channel extending to the outlet, and a passageway at a position where there is communication outwardly from the interior channel; and there is an annular member between the probe and the interior of the housing for sealing the inlet, with the annular member being depressible to the position of the passageway in the stationary probe. Because of the location of the probe and the annular member relative to the inlet easy swabbing across the inlet and exterior surface is facilitated. Swabbing is further facilitated where the annular member is flush with the inlet. 
     The apparatus of the invention encompasses means having an exterior surface at a level containing an inlet; means centered in the inlet at the level of the exterior surface and having a passageway for communicating with the inlet and extending to an interior channel for communicating with an outlet; and means depressible at the inlet to the position of the passageway; whereby the exterior surface, the depressible member and the channel containing member can be swabbed to reduce contamination and pathogens before the depressible member is depressed. 
     The housing of the invention has an interior with a bore extending from an inlet into the housing; a stationary probe is centered in the housing and included in any hypothetical extension of the inlet surface; the probe has exterior and an interior channel extending to the outlet, with a passageway communicating between the interior channel and the exterior of the probe; and an annular member between the probe and the interior of the housing seals the inlet and is depressible to the position of the passageway in the probe. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     Other aspects of the invention will become apparent after considering several illustrative embodiments taken in conjunction with the drawings in which: 
     FIG. 1A is an enlarged section, taken along a diameter, through a swabbable check valve embodying the invention; 
     FIG. 1B is a top view of the swabbable check valve of FIG. 1A before sectioning; 
     FIG. 1C is a full-scale view of the swabbable check valve of FIG. 1A, with its top view shown in FIG. 1D; 
     FIG. 2A is a partial view of the upper portion of the swabbable check valve of FIG. 1A; 
     FIG. 2B is an alternative embodiment with a modified upper portion for the swabbable check valve of FIG. 1A; 
     FIG. 2C is another alternative embodiment with a modified upper portion swabbable check valve of FIG. 1A; 
     FIG. 3A shows the swabbable check valve of FIG. 2C being engaged by the Luer end of a syringe preparatory to needleless injection of fluid through the valve; 
     FIG. 3B is a sectional view of FIG. 3A, taken along the lines  3 B— 3 B, illustrating the sealing of the inlet; 
     FIG. 3C is a expanded sectional view of the valve and Luer actuator end of FIG. 3A showing the depression of the Luer end into the bore of the swabbable check valve; 
     FIG. 3D is a sectional view of FIG. 3C, taken along the lines  3 D— 3 D, illustrating a portion of the flow channel; 
     FIG. 3E is a sectional view of FIG. 3C, taken along the lines  3 E— 3 E, illustrating the further aspects of sealing; and 
     FIG. 4 is a sectional view of a “Y” site incorporating the swabbable check valve of the invention. 
    
    
     DETAILED DESCRIPTION 
     With reference to the drawings, the check valve  10  of FIG. 1A includes a tubular housing  11  with two parts  11 - 1  and  11 - 2 . The part  11 - 1 , which occupies an “upper” position in FIG. 1A, contains an annular sealing member  12  that surrounds the upper portion of a stationary probe  13 . The probe  13  is centered in the bore B of the housing  11  and contains an axial slot  13 - s  that extends to an outlet  11 - o  of the housing  11 . 
     The upper portion of the sealing member  12 , below the inlet  11 - i  of the housing  11 , slidably engages the upper end of the probe  13 , while the intermediate portion of the sealing member  12 , adjoining the slot  13 - s,  is spaced from the probe  13 , which returns to sealing engagement with the member  12  at its base  12 - b.    
     A closed and blunt end  13 - b  of the probe  13  is elevated above the valve inlet  11 - i  to serve as a locator for an external member by which the sealing member  12  is depressible, as explained below. The sealing member  12  is held in its operative sealing position against a bore flange  11 - f  by a helical spring  14  acting against a flange  13 - f  of the sealing member  13 . 
     The parts  11 - 1  and  11 - 2  of tubular housing  11  are joined together by a snap lock  11 - k,  with the upper part  11 - 1  in contact with a circumferential seal  15  that is supported by the lower part  11 - 2 . The bore B of the housing upper part  11 - 1  has portions  11   a,    11   b  and  11   c,  of different diameters. The bore portion  11   a  serves as a female Luer inlet and has its walls tapered accordingly. The portion  11   b  is enlarged to accommodate the main body of the sealing member  12 , which is surrounded by the spring  14  and thus supports the seal  12 - b,  while the portion  11   c  accommodates the compression of the spring  14 . 
     The exterior of the housing  11  is provided at its inlet end  11 - i,  also shown in FIG. 1B, with threads  11 - s  and has a a male Luer  11 - m  at its outlet end  11 - o.  The portion  11 - 2  has ribs  11 - r.  The functions of the threads  11 - s  and the male Luer  11 - m  will presently become apparent. The housing may be formed of any suitable material, such as an elastomer or synthetic resin capable of being formed or molded. 
     While the valve  10  of FIG. 1A has been shown enlarged for clarity, the invention contemplates miniaturization as indicated by the full-scale elevational view of FIG.  1 C and the corresponding top view of FIG.  1 D. 
     The annular sealing member  15  is an elastomeric O-ring having an outer diameter slightly larger than the inner diameter of the lower part  11 - 2 , and encircles the lower portion of the spring  14 . The probe  13  is hollow, desirably of the same material as the housing, and closed at its outer end  13 - b,  capping a hollow interior that extends outwardly to the outlet  11 - o  and communicates, in the upper part of the probe  13 , with region between the probe and the member  12  by way of the slot  13 - s.    
     While the sealing member  12 , desirably elastomeric, is shown as being of a length shorter than the axial dimension of the housing  11 , it may be elongated and incorporated functionally into the spring  14 , which surrounds the co-axially mounted probe  13 . The probe  13  is fixedly held, preferably by being integral with, and extending upwardly from the lower part  11 - 2 . Like the tubular housing  11 , the probe  13  can be formed of a moldable plastic, such as nylon. 
     Since the valve  10  is operated by an external member such as the Luer end of a syringe, the tip  13 - b  of FIG. 1A, which has been reproduced in FIG. 2A, serves as a fitment locator, of which FIG. 2A is merely representative. Although the outer end of the sealing member  12  is flush with the inlet  11 - i  in FIG. 2A, it may be depressed as shown for the member  12 ′ in FIG. 2B, and the tip  13 - b  may be squared as illustrated by the tip  13 - b′  of FIG.  2 C. 
     When the valve  10  is to be operated, an external member such as the male Luer outlet  38  of FIG. 3A is brought into contact with the sealing member  32 , after being guided in position by the locator tip  33 - b  of the probe  33 . It will be noted that the outlet  38  corresponds to the outlet  11 - m  of FIG.  1 A and can take the form of the tip of a syringe. From an inspection of the cross-section shown in FIG. 3B, it will be apparent that the sealing member  32  provides a fluid-tight fit with the shoulder  31 - f  and with the outer unslotted end portion of the probe  33 . 
     It also is evident that the sealing member  32  may be pushed or forced inwardly from its normal seating position. When forced inwardly as shown in FIG. 3C, the sealing member  32  extends below the transverse slot  33 - s  and thus establishes open communication for fluid through the housing  31  in either direction, e.g. inwardly or outwardly of the valve  30 , as indicated by the double-headed arrows A. 
     The nature of the through-passage is illustrated by FIGS. 3D and 3E. In FIG. 3D the flow is confined to the slot  33 - s  and there is no flow in the interval I between the sealing member  32  and the housing  31 . In FIG. 3E the flow is confined to the bore B, with no flow in the interval I′ between the spring  34  and the housing  31 , but with a seal being proved by the spring  34  bearing against a support ring  32 - s  of the member  32 , establishing a seal of the member  32  against the probe  33 . 
     The check valves  10  and  30  of the invention have a wide variety of uses, besides with catheters and the like. One such use is illustrated in cross-section in FIG. 4 where a valve substantially like the valve  10  of FIG. 1A has been incorporated into a “Y” site  40 , that can be used, for example, in an IV (IntraVenous) procedure where the inlet branch IB of the Y site is connected to a container of saline solution that is fed through an outlet branch OB to a patient. The side branch SB of the site  40  can be used to inject medication into the patient. In prior practice the side branch SB channel C would be accessed through a needle actuated valve, but in the interest of avoiding needle sticks, needleless valves have been substituted. However, as noted above, the typical needleless valve has a long inlet channel in which contaminants and pathogens can accumulate. 
     When the valve  10  of the invention is adapted to form the valve  41  of FIG. 4, the inlet  41 - 1  is swabbable by being wiped with a disinfectant so that when a Luer fitting is brought into contact with the sealing member  42 , after being guided by the fitment  43 - b,  the desired medicament can be infused with reduced chance of contamination and no need to used a needle mounted syringe to make the injection. Parts  41 - 1 ,  42 ,  42 - s,    43 ,  43 - s  and  44  correspond to the parts  11 - 1 ,  12 ,  12 - s,    13 ,  13 - s  and  14  of FIG.  1 A. 
     While preferred embodiments have been shown and described, it is to be understood that changes in details of construction and method from what has been illustrated may be made without departing from the spirit and scope of the invention as defined by the appended claims.