GB2122101A - Microbial filter - Google Patents

Abstract

A microbial filter for removing contaminants and disinfecting a fluid flowing therethrough includes a cylindrical filter screen (26) disposed upstream from a disinfectant means (54) such that contaminants greater than a predetermined size are removed from the fluid as it flows through the filter in order to reduce the organic load on the disinfectant. The disinfectant (54) is preferably contained between a pair of filter screens (48, 50) to allow the device to function in vertical or non-vertical positions. <IMAGE>

Description

SPECIFICATION Microbial valve device Background and Summary of the Invention The invention relates generally to a device for removing contaminants from fluid. More specifically, the invention preferably relates to medical usage of such a device for removing and disinfecting microbial organisms from fluids associated therewith.

A A major problem experienced by hospitals and other health care providers is the relatively high incidents of nosocomial infections resulting from, or contracted during, a patient's recovery period.

One frequently-encountered example, among many of such infections, is a bladder or kidney infection caused by bacterial or viral organisms entering the body during urinary catheterization.

Other possible sources of infection include intravenous fluids, saline solutions, and various fluids used in wound irrigation.

In accordance with the present invention, a microbial valve device is provided which employs a disinfectant, such as Pentacide or Triocide, for disinfecting microbial organisms present in a fluid flowing therethrough. The disinfectant is contained in a chamber of the microbial valve device downstream of a fine-mesh screen or filter member which removes organic material greater than a predetermined size and thereby reduces the otherwise high organic load placed on the disinfectant as a result of the presence of such large particles. Such pre-filtering of the fluid increases the effectiveness of the disinfectant and prolongs its life. Triocide and Pentacide are trademarks of Water Technologies Corporation, Ann Arbor, Michigan.

In the preferred embodiment, the disinfectant is located within an in-line housing and is contained between two fine-mesh retainer screens to allow the device to function in vertical or horizontal positions. The disinfectant chamber of the housing communicates with an open end of the generally cylindrical screen member which is located in an upstream tubular filter chamber such that no fluid may reach the disinfectant without first passing through the screen member and such that no microbial organisms may enter the upstream portion of the fluid line without passing through the disinfectant material. The configuration of the elongated, generally cylindrical screen member coaxially disposed in an elongated tubular filter chamber maximizes the filter area while minimizing the fluid pressure drop across the device.At least the filter chamber portion of the housing is preferably transparent to allow the condition of the screen member to be conveniently monitored so that the device can be replaced when the screen member becomes clogged.

These and other features of the present invention are described below and illustrated in the accompanying drawings.

Brief Description of the Drawings Figure 1 is a longitudinal cross-sectional view of a preferred microbial valve device according to the present invention.

Figure 2 is a cross-sectional view taken along line 2-2 of Figure 1.

Figure 3 is a cross-sectional view taken along line 3-3 of Figure 1.

Figure 4 is an enlarged, detail view of the circled portion of Figure 1.

Detailed Description of the Preferred Embodiments Figures 1 through 4 depict a preferred embodiment of the microbial valve device of the present invention for purposes of illustration only.

One skilled in the art will readily recognize, however, that the principles of the present invention are equally applicable to devices having configurations or shapes other than those illustrated in the drawings.

The preferred microbial valve device, generally illustrated by reference numeral 10, includes a housing 12 with a fluid inlet connector 14 and a fluid outlet connector 16 at its opposite ends. The fluid inlet and outlet connectors 14 and 16 have ends adapted to be sealingly connected to an upstream fluid conduit 18 and a downstream fluid conduit 19, respectively. Although various components of the microbial valve device 10 are shown in the drawings as fabricated from plastic, other materials may also be employed.

The housing 12 is generally cylindrical in shape and includes a filter chamber 20 and a disinfectant chamber 22. A generally cylindrical screen member 26 is coaxially disposed within the filter portion 20 and is held in place by a number of support ribs 28 protruding axially from a ring member 30. The screen member 26 includes a closed end 32 oriented toward the fluid inlet connector 14 and an open end 34 formed by the ring member 30. The closed end 32 of the screen member 26 is engaged by a number of support fins 36 extending radially inward from the wall of the fluid inlet connector 14. The ring member 30 and the support fins 36 maintain the screen member in a coaxial position within the filter chamber 20 to form an annular space 40 therebetween.The ring member 30 is attached to, or integrally formed with, the outlet end of the filter chamber 20 such that any fluid entering the filter chamber 20 from the inlet connector 14 must pass through the wall of the screen member 26 before entering the disinfectant chamber 22.

One skilled in the art will readily recognize that the support ribs, screen member, ring member and filter chamber may also be integrally formed as one-piece structure.

The disinfectant chamber 22 communicates with the open end 34 of the screen member 26 and includes retaining screens 48 and 50 at its opposite ends. A disinfectant material 54 is contained within the disinfectant chamber 22 between retaining screens 48 and 50, thereby allowing the device to function in any vertical or non-vertical position. Examples of the disinfectant material 54 include Pentacide and Triocide, but one skilled in the art will readily recognize that other disinfectant materials may be employed which are suitable for the fluid passing through the microbial valve device 10.

Although the microbial valve device 10 may find many fluid disinfecting applications, its operation is described for purposes of illustration as installed in a catheter line. The microbial valve device 10 is installed in the catheter line by fitting fluid conduits 18 and 29 onto inlet and outlet connectors 14 and 16, respectively. The fluid flow enters the device and flows into the annular space 40 around the screen member 26, thus filling the filter chamber 20. Any organic material of a size greater than the openings in the fine-mesh screen member 26 are trapped and thus removed from the fluid as it flows into the screen member interior. The filtered fluid then discharges through the open end 34 of the screen member into the disinfectant chamber 22.Before coming into contact with the disinfectant material 54, the fluid is again filtered by the retaining screen 48 which further insures that the organic load on the disinfectant material has been minimized. The fluid is then disinfected by the disinfectant material 54 and passes through the retaining screen 50 into the fluid outlet connector 16 where it is finally discharged into the downstream fluid conduit 19.

The annular space 40 and the disinfectant chamber 22 are isolated by the screen member 26, and thus any fluid reaching the disinfectant material 54 must first pass through the screen member 26. Likewise, no microbial organisms may enter the upstream fluid conduit 1 8 from the downstream conduit 19 without passing through the disinfectant material 54.

Preferably, the filter portion 20 of the housing 1 2 is transparent to permit easy observation of the condition of the screen member 26. As the screen member 26 eventually becomes clogged, such condition may be readily observed and the microbial valve device may be replaced before it is rendered ineffective or totally clogged.

The construction of the microbial device 10 provides for improved effectiveness and increased life of the disinfectant material 14 by first removing organic material greater than a predetermined size and thereby reducing the otherwise high organic load on the disinfectant material. Furthermore, the generally cylindrical configuration of the screen member 26 coaxially disposed within the generally cylindrical filter chamber 20 provides for a relatively large filter area as well as minimizing the pressure drop across the device and therefore increases the effective filtration without unduly restricting the flow.

Claims (8)

1. A microbial valve device for use in a fluidcarrying conduit, said microbial valve device comprising -housing means, inlet means for receiving said fluid from said conduit, filter means in said housing means for receiving said fluid from said inlet means and removing organic materials greater than a predetermined size therefrom, disinfectant means in said housing means for receiving and disinfecting the filtered fluid from said filter means, and outlet means for discharging the filtered and disinfected fluid from said disinfectant means into said conduit, said microbial valve device thereby preventing the passage of infectious materials therethrough.

2. A microbial valve device according to claim 1, wherein said housing means includes e generally cylindrical filter chamber, and wherein said filter means includes a generally cylindrical screen member coaxially disposed within said filter chamber, said cylindrical screen member having a closed end oriented toward said inlet means and an open end communicating with said disinfectant means, whereby said fluid from said inlet means passes through the wall of said cylindrical screen member before contacting said disinfectant means.

3. A microbial valve device according to claim 2, wherein said screen member includes a ring member at its open end and a number of circumferentially-spaced support ribs extending axially between said ring member and said closed end, said support ribs maintaining said screen member in said generally cylindrical configuration.

4. A microbial valve device according to claim 3, wherein said inlet means includes a number of circumferentially-spaced support fins extending radially therefrom, said support fins engaging said closed end of said screen member to maintain a generally uniform annular space between the wall of said filter chamber and said screen member, said annular space being separated from said disinfectant means by said screen member.

5. A microbial valve device according to claim 2 or 4, wherein said housing means further includes a disinfectant chamber communicating with said open end of said cylindrical screen member and with said outlet means, said chamber including a first retaining screen disposed between said disinfectant chamber and said open end of said cylindrical screen member and a second retaining screen disposed between said disinfectant chamber and said outlet means, said disinfectant means being contained within said disinfectant chamber by said first and second retaining screens.

6. A microbial valve device according to claim 5, wherein the filter chamber of said housing is transparent.

7. A microbial valve device according to claim 6, wherein said ring member is integrally formed with said filter chamber.

8. A microbial valve device according to claim 7, wherein said filter chamber, said support ribs, said ring member and said filter chamber are integrally formed in a one-piece structure.

.9. A microbial valve device constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.