Trap guard device

Information

  • Patent Grant
  • 6795987
  • Patent Number
    6,795,987
  • Date Filed
    Tuesday, September 17, 2002
    22 years ago
  • Date Issued
    Tuesday, September 28, 2004
    20 years ago
  • Inventors
  • Examiners
    • Huson; Gregory L.
    • Huynh; Khoa
    Agents
    • Moyne; Mary M.
    • McLeod; Ian C.
Abstract
A valve for use in a floor drain to prevent the backflow of fluids from the drain system. The valve includes a valve member and a collar. The first end of the valve member is mounted to the outer surface of the second portion of the collar. In the normal position, the sidewall of the valve member at the second end of the valve member is curled and the valve is in the closed position. When a preset amount of fluid pressure is provided through the collar to the first end of the valve member, the sidewall of the valve member flexes to an open position forming an inner passageway between the ends of the valve member.
Description




CROSS-REFERENCE TO RELATED APPLICATIONS




Not Applicable




STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT




Not Applicable




BACKGROUND OF THE INVENTION




(1) Field of the Invention




The present invention relates to a valve for use in a floor drain connected to a drain system to prevent gases from escaping from the drain system. In particular, the present invention relates to a valve for use in a floor drain which has a flexible valve member.




(2) Description of the Related Art




The related art has shown various trap valves which have a flexible sidewall which is normally in the closed position to prevent the backflow of fluids. Illustrative are U.S. Pat. No. 803,979 to Bonnell; U.S. Pat. No. 3,707,986 to Breen and U.S. Pat. No. 4,870,992 to Irwin et al.




Bonnell describes a seal trap for the drain pipe of sinks which prevents the backflow of noxious odors, gases, and water from such pipes. The seal device is inserted into a hollow tubular casing which is mounted in the drain pipe of the sink. The seal device is constructed of flexible material which possesses elastic qualities and is impervious to water and other liquids.




Breen describes a diaphragm valve for mounting in the drain line of a sink. The device is constructed of a tubular resilient member having a transverse seat at the upper end for securing the device in the drain. Below the seat is a cylindrical section and a conical section from which depends three (3) axially extending and radially orientated flanges. The valve prevents the back up of water and gases through the drain of a sink.




Irwin et al describes a backflow prevention device adapted to be installed in the drain opening of fluid conduits. The device includes a drain insert member connected to the fluid conduit adjacent the inlet opening. A valve member is positioned in the insert member adjacent the inlet opening of the fluid conduit. The valve member includes a substantially rigid, annular shaped portion and a deformable wall connected thereto and extending outwardly therefrom. The annular portion is clamped between the edge of the insert member and the inlet of the waste line. The deformable wall has a first portion in close engagement with the fluid conduit and a second portion. The second portion is normally disposed in engagement with the first portion. The second portion deforms in response to fluid pressure, from a closed position to an open position. In the open position, the valve member provides a wide open passageway to accommodate the free flow of fluids through the valve and into the conduit. When the valve member is in the closed position, the flow of fluids in the opposite direction is prevented. This invention is limited with regard to the size of the conduit due to the fact that the valve member rests adjacent a side of the fluid conduit.




Also of interest are U.S. Pat. Nos. 2,328,382; 2,352,642; 2,371,449; 2,382,427; 2,594,318 and 2,598,002 all to Langdon which show various types of flexible check valves, some of which also are for use in vacuums or siphon breaking devices.




Only of minimal interest are U.S. Pat. No. 194,329 to Buhrer and U.S. Pat. No. 220,559 to Wilson.




Buhrer describes a stench trap for sinks. The trap includes a flexible valve. In this invention, the casing for the valve provides an inclined seat for the valve upon which the valve rests.




Wilson shows a gas check valve having a pliable section which is mounted in a chamber filled with water. The pressure of the water in the chamber causes the pliable section to close tightly and make a gas-tight joint.




Of some interest are U.S. Pat. No. 4,524,805 to Hoffman; U.S. Pat. No. 5,551,483 to Hochstrasser; U.S. Pat. No. 5,881,772 to Bennett; U.S. Pat. No. 6,092,551 Bennett and U.S. Pat. No. 4,289,166 to Haines which show elastomeric valves and U.S. Pat. No. 3,118,468 to Bochan which describes a resilient member check valve.




There remains the need for a valve for inserting into the floor drain of a drain system which has a flexible sidewall which curls at one end to prevent backflow of fluids through the valve into the floor drain.




SUMMARY OF THE INVENTION




A valve for use in a floor drain to prevent the backflow of fluids such as sewer gases from the drain system and sewer system. The valve includes a valve member and a collar. The first portion of the collar has an outer diameter slightly less than the diameter of the center bore of the drain insert of the floor drain. A seal can be provided around the outer surface of the collar to form a seal between the outer surface of the collar and the center bore of the drain insert. The valve member has a first end and a second end with a flexible sidewall extending therebetween. The first end of the valve member is mounted to the outer surface of the second portion of the collar. In the normal position, the second end of the valve member is curled away from the longitudinal axis of the valve and the valve is in the closed position. The curled second end of the valve member helps to prevent fluids from entering the valve through the second end of the valve member. When a preset amount of fluid pressure is provided through the collar to the first end of the valve member, the sidewall flexes to an open position forming a complete inner passageway between the ends of the valve member. The first end of the collar can be provided with tabs in the inner passageway which allow for easy removal of the valve from the floor drain. The valve can be positioned in a floor drain having a drain insert and a strainer top. The valve could also be positioned in a hub drain having a pipe which extends above the floor and which has an open top end.




The present invention relates to a valve for use in a floor drain connected to a drain system to prevent gases from escaping from the drain system through the floor drain which comprises: a collar having a first end and a second end with an inner passageway extending between the ends; and a valve member having a first end and a second end with a flexible sidewall extending between the ends and forming an inner passageway, wherein the first end of the valve member is connected to the second end of the collar wherein in a normal position, the inner passageway of the valve member tapers in cross-section from the first end toward the second end of the valve member and the flexible sidewall adjacent the second end of the valve member is curled and wherein when fluid is introduced into the inner passageway of the valve member at the first end of the valve member, the flexible sidewall uncurls and the inner passageway of the valve member expands adjacent the second end such as to allow fluid to exit the valve member through the second end of the valve member.




Further, the present invention relates to a floor drain for use in a drain system and having a drain insert with a center bore and a strainer top for mounting on one end of the drain insert, the improvement which comprises: a valve mounted in the center bore of the floor drain to prevent fluids in the drain system from escaping the drain system through the floor drain, the valve including: a collar having a first end and a second end with an inner passageway extending between the ends; and a valve member having a first end and a second end with a flexible sidewall extending between the ends and forming an inner passageway, wherein the first end of the valve member is connected to the second end of the collar, wherein in a normal position, the inner passageway of the valve member tapers in cross-section from the first end toward the second end of the valve member and the flexible sidewall adjacent the second end of the valve member is curled and wherein when fluid is introduced into the inner passageway of the valve member at the first end, the flexible sidewall uncurls and the inner passageway of the valve member expands adjacent the second end such as to allow fluid to exit the valve member through the second end of the valve member.




Still further, the present invention relates to a valve for use in a floor drain connected to a drain system to prevent gases from escaping from the drain system through the floor drain which comprises: a collar having a first end and a second end with an inner passageway extending between the ends and forming a longitudinal axis of the collar; and a valve member having a first end and a second end with a flexible sidewall extending between the ends and forming an inner passageway, wherein the first end of the valve member is connected to the second end of the collar, wherein in a normal position, the inner passageway of the valve member tapers in cross-section from the first end of the valve member to the second end of the valve member and the flexible sidewall adjacent the second end is curled away from the longitudinal axis of the collar and wherein when fluid is introduced into the inner passageway of the valve member at the first end, the flexible sidewall uncurls and the inner passageway of the valve member expands adjacent the second end such that the valve is in the open position and allows the fluid to exit through the second end of the valve member.




Further still, the present invention relates to a method for preventing gases in a drain system from escaping through an entrance of the drain system while allowing fluids to enter the drain system through the entrance, which comprises the steps of: providing a floor drain having a drain insert with a center bore and having a strainer top; providing a valve including a collar having a first end and a second end with an inner passageway extending between the ends; and a valve member having a first end and a second end with a flexible sidewall extending between the ends of the valve member and forming an inner passageway of the valve member, wherein the first end of the valve member is connected to the second end of the collar wherein in a normal position, the inner passageway of the valve member tapers in cross-section from the first end to the second end of the valve member and the flexible sidewall adjacent the second end is curled; connecting the floor drain to the drain system; positioning the valve in the center bore of the drain insert of the floor drain such that the valve member extends through the center bore of the floor drain and into the drain system wherein the collar of the valve forms a seal with the center bore of the drain insert; and positioning the strainer top on one end of the drain insert of the floor drain opposite the valve member such as to enclose the valve in the drain insert wherein in the normal position, the second end of the valve member is closed and prevents gases from exiting the drain system through the floor drain and wherein when fluid is inserted into the inner passageway of the valve member at the first end of the valve member, the flexible sidewall uncurls and the inner passageway of the valve member expands adjacent the second end of the valve member such as to allow fluid to exit the valve member at the second end and enter the drain system.




The substance and advantages of the present invention will become increasingly apparent by reference to the following drawings and the description.











BRIEF DESCRIPTION OF THE DRAWING(S)





FIG. 1

is a cross-sectional view of the valve


10


positioned in a floor drain


100


showing the valve


10


in the normal closed position with the drain shown in the open position in phantom.





FIG. 2

is a cross-sectional view of the valve


10


.





FIG. 3

is an exploded, cross-sectional view of the valve


10


.





FIG. 4

is a top view of the valve


10


.





FIG. 5

is a cross-sectional view along line


5





5


of

FIG. 4

showing the collar


12


.





FIG. 6

is a cross-sectional view showing the valve


10


positioned in a hub drain.











DESCRIPTION OF THE PREFERRED EMBODIMENT(S)




The present invention relates to a valve


10


for use in a floor drain


100


or


110


to prevent fluids such as sewer gases from escaping from the drain system


150


or sewer system through the floor drain


100


or


110


. In one (1) embodiment, the floor drain


100


is similar to standard floor drains well known in the art. The floor drain


100


includes a strainer top or grate


102


, a drain insert


104


and a mounting flange


106


. The mounting flange


106


is configured to mount or be secured to the entrance of the drain system


150


(FIG.


1


). The mounting flange


106


can be secured to the drain system


150


by any well known means such as fasteners


108


. The mounting flange


106


has a center opening


106


A into which is mounted the drain insert


104


. The drain insert


104


has a first end


104


A and a second end


104


B with a center bore


104


C extending therebetween. The center bore


104


C of the drain insert


104


has a first portion adjacent the first end


104


A and a second portion adjacent the second end


104


B. The first portion of the center bore


104


C at the first end


104


A of the drain insert


104


is tapered to direct the flow of fluids toward the center bore


104


C. In one (1) embodiment, the second portion of the drain insert


104


adjacent the second end


104


B of the drain insert


104


is cylindrical. The outer surface of the second portion of the drain insert


104


can be provided with threads which engage threads on the center opening


106


A of the mounting flange


106


such that the drain insert


104


is threadably mounted in the center opening


106


A of the mounting flange


106


. The strainer top


102


is provided for removably securing over the opening of the center bore


104


C at the first end


104


A of the drain insert


104


.




In another embodiment, the floor drain is a hub drain


110


having an open first end


110


A and a second end


110


B with a center bore


110


C extending therebetween (FIG.


6


). The first end


110


A of the hub drain


110


extends above the floor


114


in which it is mounted. The second end


110


B of the hub drain


110


is connected by an inner connector pipe


112


to the drain system


150


. The first section of the center bore


110


C at the first end


110


A of the hub drain


110


is enlarged to enable liquid to flow into the drain system


150


. The center bore


110


C tapers to a second section adjacent the second end


110


B. The connector pipe


112


extends upward in the center bore


110


C such that the open first end


112


A of the connector pipe


112


is flush with the op of the second section of the adjacent tapered section of the center bore


110


C.




The valve


10


includes a collar


12


and a valve member


16


connected to the collar


12


(FIGS.


2


and


3


). The collar


12


has a first end


12


A and a second end


12


B with an inner passageway


12


C extending between the ends


12


A and


12


B. In one (1) embodiment, the diameter of the inner passageway


12


C of the collar


12


is essentially constant between the ends


12


A and


12


B. The axis of the inner passageway


12


C of the collar


12


forms the longitudinal axis A—A of the valve


10


(FIG.


1


). In one (1) embodiment, the collar


12


has a cylindrical shape. The collar


12


has a first portion


12


D adjacent the first end


12


A and a second portion


12


E adjacent the second end


12


B. The outer diameter of the first portion


12


D is greater than the outer diameter of the second portion


12


E such that a shoulder


12


F is formed on the outer surface of the collar


12


between the first and second portions


12


D and


12


E. In one (1) embodiment, the outer diameter of the first portion


12


D of the collar


12


is essentially equal to the diameter of the center bore


104


C of the drain insert


104


such that the collar


12


can be positioned in the center bore


104


C of the drain insert


104


. The inner passageway


12


C adjacent the first end


12


A of the collar


12


can be provided with tabs


14


which are spaced apart around the circumference of the inner passageway


12


C and which extend inward toward the center of the inner passageway


12


C (FIGS.


4


and


5


).




The valve member


16


has a first end


16


A and a second end


16


B with a flexible sidewall


16


C extending therebetween and forming an inner passageway


16


D. The first end


16


A is mounted on the second portion


12


E of the collar


12


such that the second portion


12


E of the collar


12


is in the inner passageway


16


D of the valve member


16


and the inner passageway


12


C at the first end


12


A is coaxial with the longitudinal axis A—A of the valve


10


. The flexible sidewall


16


C is of such a size that the first end


16


A of the sidewall


16


C can be stretched to mount over the second portion


12


E of the collar


12


. The valve member


16


can be constructed of a durable, flexible resilient material having memory. In one (1) embodiment wherein the sidewall is constructed of a material having memory, the memory of the flexible sidewall


16


C flexes the sidewall


16


C inward and holds the sidewall


16


C in place on the collar


12


by friction. The first end


16


A of the valve member


16


can be mounted to the collar


12


by any well known means such as by friction fit or by use of an adhesive. In one (1) embodiment, the flexible sidewall


16


C is constructed of a first panel


18


and a second panel


20


. Each panel


18


or


20


has a rectangular shape with a first end


18


A or


20


A and a second end


18


B or


20


B with sides (not shown) extending therebetween. To form the sidewall


16


C, the panels


18


and


20


are connected together along the sides with the first end


18


A of the first panel


18


adjacent the first end


20


A of the second panel


20


. When the panels


18


and


20


are connected together to form the sidewall


16


C, the panels


18


and


20


are not connected together at either end. The second end


16


B of the valve member


16


is curled away from the axis A—A of the valve


10


. In one (1) embodiment, the second end


16


B of the valve member


16


is curled by heating the sidewall


16


C and curling the sidewall


16


C using a heated, cylindrical rod. In one (1) embodiment, the second end


16


B of the valve member


16


has a J-shape. In the normal position, in one (1) embodiment, where the flexible sidewall


16


C is constructed of panels


18


and


20


, the panels


18


and


20


are essentially parallel to each other at the second end


18


B or


20


B. In one (1) embodiment, the valve member


16


is constructed of a specifically formulated elastomeric flexible PVC material such as SUNPRENE™ which will remain flat and which has memory. An o-ring or seal


22


can be provided between the first end


16


A of the valve member


16


and shoulder


12


F on the outer surface of the collar


12


(FIGS.


2


and


3


). The seal


22


can be constructed as part of the valve member


16


. In one (1) embodiment, the outer diameter of the first portion


12


D of the collar


12


is greater than the outer diameter of the second portion


12


E of the collar


12


with the valve member


16


attached. In one (1) embodiment, the seal


22


has an outer diameter greater than the diameter of the first portion


12


D of the collar


12


.




The valve


10


of the present invention is intended to be used in a floor drain


100


or


110


connected to a building drain system


150


. However, it is understood that the valve


10


could be used in any drain where it is desirable to prevent fluids from exiting the drain system


150


or sewer system through the drain. The valve


10


can be positioned in the floor drain


100


or


110


before or after the floor drain


100


or


110


is mounted in position in the building. In the embodiment having the floor drain


100


with a drain insert


104


, the valve


10


is inserted into the center bore


104


C of the drain insert


104


. First, the second end


16


B of the valve member


16


is inserted into the center bore


104


C of the drain insert


104


. The valve


10


is inserted until the second portion


12


E of the collar


12


is fully within the center bore


104


C and the seal


22


contacts the sides of the center bore


104


C. The valve


10


is inserted into the center bore


104


C of the drain insert


104


such that the first end


12


A of the collar


12


does not extend beyond the first end


104


A of the drain insert


104


. In one (1) embodiment, the collar


12


of the valve


10


is completely within the cylindrical, second portion of the center bore


104


C of the drain insert


104


. In one (1) embodiment, the first end


12


A of the collar


12


of the valve


10


is spaced slightly below the strainer top


102


. Once the valve


10


is in position in the drain insert


104


, the strainer top


102


is placed on the drain insert


104


. The strainer top


102


prevents the valve


10


from moving upward out of the drain insert


104


. In another embodiment, where the floor drain is a hub drain


110


, the valve


10


is positioned in the center bore


112


C of the connector pipe


112


at the open top


112


A such that liquid enters the open first end


110


A of the hub drain


110


and flows along the tapered section of the center bore


110


C into the open first end


12


C of the collar


12


(FIG.


6


). In one (1) embodiment, the valve


10


is held in place by a friction fit between the seal


22


and the inner surface of the center bore


104


C of the drain insert


104


or the inner surface of the center bore


112


C of the connector pipe


112


. The seal


22


also provides a fluid tight seal between the center bore


104


C or


112


C and the collar


12


of the valve


10


. In another embodiment, an adhesive or caulk (not shown) is provided between the outer surface of the collar


12


and the inner surface of the center bore


104


C or


112


C.




In the normal position, the second end


16


B of the valve member


16


is in the closed position. In this position, no fluids from the drain system


150


or other plumbing or sewer system are able to enter the valve member


16


through the second end


16


B. Thus, the valve


10


with the valve member


16


in the closed position prevents fluids, such as for example sewer gases, from exiting the drain system


150


or plumbing or sewer system through the drain. When fluids flow into the floor drain


100


or


110


and into the center bore


104


C or


112


C of the drain insert


104


or connector pipe


112


, the fluids enter the inner passageway


12


C of the collar


12


and flow into the inner passageway


16


D of the valve member


16


and into contact with the flexible sidewall


16


C of the valve member


16


. When the pressure of the fluid in the inner passageway


12


C of the collar


12


reaches a predetermined amount, the flexible sidewall


16


C flexes or moves and the valve


10


opens. As the valve


10


opens, the second end


16


B of the valve member


16


uncurls and the flexible sidewall


16


C of the valve member


16


moves to expand the size of the inner passageway


16


D to the second end


16


B of the valve member


16


and open the second end


16


B of the valve member


16


. In one (1) embodiment, the pressure of the fluid causes the diameter of the inner passageway


16


D of the valve member


16


between the second end


12


B of the collar


12


and the second end


16


B of the valve member


16


to be essentially equal to the diameter of the inner passageway


12


C of the collar


12


. In one (1) embodiment, when the valve


10


is in the fully, open position, the longitudinal axis of the inner passageway


16


D of the valve member


16


is coaxial with the longitudinal axis A—A of the valve


10


and the longitudinal axis of the collar


12


(FIG.


1


). In the one (1) embodiment where the sidewall


16


C is formed by panels


18


and


20


, the fluid pressure forces the panels


18


and


20


apart to form the inner passageway


16


D. The valve


10


continues to remain open as long as the fluid pressure is present. When the fluid is reduced or removed and the fluid pressure is reduced below the predetermined amount, the second end


16


B of the valve member


16


closes and returns to the normal, curled position. The curling of the second end


16


B of the flexible valve member


16


assists in preventing the fluids from entering the inner passageway


16


D of the valve member


16


through the second end


16


B of the valve member


16


. To remove the valve


10


from the floor drain


100


or


110


, a removal tool (not shown) is positioned on the tabs


14


and the valve


10


is pulled upward out of the floor drain


100


or


110


. This allows the valve


10


to be replaced without having to remove the floor drain


100


or


110


.




It is intended that the foregoing description be only illustrative of the present invention and that the present invention be limited only by the hereinafter appended claims.



Claims
  • 1. A floor drain used in a drain system, the floor drain having a drain insert with a center bore and a strainer top for mounting on one end of the drain insert, the improvement which comprises:a valve mounted in the center bore of the floor drain to prevent fluids in the drain system from escaping the drain system through the floor drain, the valve including: (a) a collar having a first end and a second end with an inner passageway extending between the ends and having a first portion and a second portion, wherein an outer diameter of the first portion is greater than an outer diameter of the second portion; (b) a valve member having a first end and a second end with a flexible sidewall extending between the ends and forming an inner passageway, wherein the first end of the valve member is mounted over the second portion of the collar; and (c) an o-ring positioned between the first end of the valve member and the first portion of the collar, wherein an outer diameter of the o-ring is slightly greater than a diameter of the center bore of the drain insert such that the o-ring forms a seal between the center bore of the drain insert and the collar, wherein in a normal position, the inner passageway of the valve member tapers in cross-section from the first end toward the second end of the valve member and the flexible sidewall adjacent the second end of the valve member is curled and wherein when fluid is introduced into the inner passageway of the valve member at the first end, the flexible sidewall uncurls and the inner passageway of the valve member expands adjacent the second end such as to allow fluid to exit the valve member through the second end of the valve member.
  • 2. The floor drain of claim 1 wherein the collar of the valve has a shape and size such as to closely fit within the center bore of the drain insert.
  • 3. The floor drain of claim 2 wherein a portion of the collar is cylindrical and wherein the center bore of the drain insert is cylindrical and wherein an outer diameter of the portion of the collar is slightly less than a diameter of the center bore of the drain insert.
  • 4. The floor drain of claim 3 wherein the collar has a first portion and a second portion and wherein the valve member is mounted on the second portion of the collar and wherein an outer diameter of the first portion of the collar and an outer diameter of the second portion of the collar with the valve member attached is slightly less than the diameter of the center bore of the drain insert.
  • 5. The floor drain of claim 1 wherein the center bore of the drain insert has a first portion adjacent a first end of the drain insert and a second portion adjacent the second end, wherein the second portion has a cylindrical shape with a constant diameter and wherein the collar is positioned completely within the second portion of the center bore of the drain insert.
  • 6. The floor drain of claim 1 wherein the flexible sidewall of the valve member at the second end has a J-shape.
  • 7. The floor drain of claim 1 wherein the valve member is constructed of a resilient material having a memory such that when the fluid is removed from the inner passageway of the valve member, the valve member returns to the normal position with the flexible sidewall curled at the second end of the valve member.
  • 8. The floor drain of claim 1 wherein in the normal position, the second end of the valve member is closed to prevent the fluids in the drain system from entering the inner passageway of the valve member through the second end of the valve member.
  • 9. A method for preventing gases in a drain system from escaping through an entrance of the drain system while allowing fluids to enter the drain system through the entrance, which comprises the steps of:(a) providing a floor drain having a drain insert with a center bore and having a strainer top; (b) providing a valve including a collar having a first end and a second end with an inner passageway extending between the ends and having a first portion and a second portion, wherein an outer diameter of the first portion is greater than an outer diameter of the second portion; and a valve member having a first end and a second end with a flexible sidewall extending between the ends of the valve member and forming an inner passageway of the valve member, wherein the first end of the valve member is mounted over the second portion of the collar, an o-ring positioned between the first end of the valve member and the first portion of the collar, wherein an outer diameter of the o-ring is slightly greater than a diameter of the center bore of the drain insert such that the o-ring forms a seal between the center bore of the drain insert and the collar; wherein in a normal position, the inner passageway of the valve member tapers in cross-section from the first end to the second end of the valve member and the flexible sidewall adjacent the second end is curled; (c) connecting the floor drain to the drain system; (d) positioning the valve in the center bore of the drain insert of the floor drain such that the valve member extends through the center bore of the floor drain and into the drain system wherein the collar of the valve forms a seal with the center bore of the drain insert; and (e) positioning the strainer top on one end of the drain insert of the floor drain opposite the valve member such as to enclose the valve in the drain insert wherein in the normal position, the second end of the valve member is closed and prevents gases from exiting the drain system through the floor drain and wherein when fluid is inserted into the inner passageway of the valve member at the first end of the valve member, the flexible sidewall uncurls and the inner passageway of the valve member expands adjacent the second end of the valve member such as to allow fluid to exit the valve member at the second end and enter the drain system.
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