US3712009A - Manhole closure assembly with valve relief means - Google Patents

Manhole closure assembly with valve relief means Download PDF

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US3712009A
US3712009A US00089301A US3712009DA US3712009A US 3712009 A US3712009 A US 3712009A US 00089301 A US00089301 A US 00089301A US 3712009D A US3712009D A US 3712009DA US 3712009 A US3712009 A US 3712009A
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manhole
valve
cover plate
closure assembly
vacuum
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US00089301A
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B Campagna
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FORSROC INTERNATIONAL Ltd A Co OF ENGLAND
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Assigned to CAMPAGNA, BENJAMIN J., reassignment CAMPAGNA, BENJAMIN J., SAID ASSIGNEE IS APPOINTED AS ATTORNEY IN-FACT TO EFFECT THE TRANSFER AND SALE OF ANY INTEREST SAID ASSIGNOR MAY HAVE IN SAID PATENTS Assignors: TRUONO, EUGENE J.
Assigned to FORSROC INTERNATIONAL LIMITED, A COMPANY OF ENGLAND reassignment FORSROC INTERNATIONAL LIMITED, A COMPANY OF ENGLAND ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: CAMPAGNA, BENJAMIN J., TRUONO, EUGENE J.
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    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D29/00Independent underground or underwater structures; Retaining walls
    • E02D29/12Manhole shafts; Other inspection or access chambers; Accessories therefor
    • E02D29/14Covers for manholes or the like; Frames for covers

Definitions

  • Manhole closure assembly primarily prevents drainage and storm water from emptying into manhole leading to sewerage system.
  • Closure assembly comprises cover plate sealing off manhole opening.
  • First valve is secured to cover'plate for relieving pressure inside manhole when pressure therein exceeds predetermined amount
  • second valve member is secured to cover plate for relieving vacuum inside manhole when vacuum therein exceeds predetermined amount.
  • the present invention relates to a manhole closure assembly, and more particularly to a closure that prevents drainage and storm water from emptying into a manhole that leads to a sewerage system.
  • Standard frames and covers for manholes leading to sanitary or sewerage systems include cover constructions with passageways therein that enable storm water to empty into the sewerage system.
  • the passageways in the standard cover constructions are provided for relieving internal pressure in the sanitary system as well as preventing vacuum build-ups in the system.
  • Another object of the present invention is to provide a highly efficient and easy to follow method for preventing drainage and storm water from emptying into a manhole.
  • a manhole closure assembly for primarily preventing drainage and storm water from emptying into a manhole opening covered by the closure.
  • the closure assembly comprises a cover plate sealing off the manhole opening with a first valve member secured to the plate arranged to relieve pressure inside the manhole when the pressure therein exceeds a predetermined amount.
  • a second valve member also secured to the plate is arranged to relieve vacuum inside the manhole when the vacuum therein exceeds a predetermined amount.
  • the cover plate comprises a pair of semicircular segments, and a connector strip seals and connects the semicircular segments together along their diametral edges.
  • the connector strip has a substantially I- shaped cross section.
  • One valve member is secured to one of the semicircular segments of the cover plate while the other valve member is secured to the second semicircular segment of the plate.
  • the manhole closure is in combination with an annular manhole frame surrounding the upper portion of the manhole and anchored thereto.
  • the annular manhole frame has an internal inwardly directed flange that supports the cover plate in sealing relationship over the manhole opening by engaging the arcuate edges of the semicircular segmentsof the cover plate and the ends of the connector strip. Sealing material is between the in wardly directed supporting flange of the manhole frame and the arcuate edges of the semicircular segments of the cover plate.
  • each valve member of the present invention each comprise a stationary valve body having at least one passageway therein that provides communication between the up side and down side of the cover plate when the valve member is open.
  • Each passageway has a taper with the upper open end thereof smaller than the lower open end thereof.
  • each valve member includes a valve body with a seat portion, a movable valve element and stem, and a biasing device between the valve stem and the valve body normally urging the valve element against the seat portion of the valve body. The valve element remains seated until the force acting upon the movable valve element in the direction opposite the force generated by the biasing device is greater than the force of the biasing device. When this condition occurs the movable valve element moves away from the seat portion of the valve body to open the valve member.
  • the seat portion includes a substantially circular sharpened edge that engages the movable valve element.
  • a ring of resilient material is carried by the movable valve element, and the ring is adapted to be engaged by the sharpened edge of the valvebody when the valve member is closed.
  • the cover plate may comprise a one piece circular segment with a pair of spaced apart housings fixed to the underside thereof.
  • the valve members are secured to the housings with one valve member associated with each housing.
  • Passageways are located in the cover plate directly over each housing for providing communication between the up side of the cover plate and the interior of the housings.
  • FIG. 2 is a sectional view taken along line 22 of FIG. 1;
  • FIG. 3 is a top plan view of another embodiment of the present invention.
  • FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;
  • FIG. 5 is a side elevational view of a valve member according to the present invention.
  • FIG. 6 is a bottom plan view of the valve member shown in FIG. 5;
  • FIG. 7 is a sectional view taken along line 7-7 of FIG. 6 with the valve member in its open position;
  • FIG. 8 is a side elevational view of another valve member according to the present invention with portions broken away to show detail and with the movable valve element shown in its unseated position inphantom outline;
  • FIG. 9 is a bottom plan view of the valve member shown in FIG. 8.
  • FIGS. 1 and 2 illustrate a manhole closure assembly 10 for primarily preventing drainage and storm water from emptying into a manhole 12 that leads to a sewerage system.
  • the upper end of most manhole constructions is surrounded by an annular manhole frame 14 embedded in a road bed 16 or similar surface construction.
  • the annular manhole frame has an upper inwardly directed flange 18 for supporting a standard manhole cover or lid (not shown).
  • the manhole lid has passageways therein, as is well known.
  • the manhole cover assembly 10 of the present invention comprises a cover plate 20 fabricated from rigid metal or similar material including a pair of semicircular segments 22, 24 and a connector strip or bar 26 that seals, supports and connects the semicircular segments together along their diametral edges 28.
  • the bar 26 may also be constructed of rigid metal and has an I- shaped cross section.
  • the annular manhole frame 14 has a lower inwardly directed flange 30 that supports the arcuate edges 32 of the semicircular segments 22, 24 of the cover plate 20.
  • the flange 30 also supports the ends 34 of the connector strip 26.
  • Caulking or other suitable sealing material 36 is located between the flange 30 and the arcuate edges of the cover plate 20. Sealing material is also located at the juncture between the diametral edges 28 and the connector strip 26 to provide an air tight seal of the cover plate over the-manhole opening.
  • the weight of. the manhole cover assembly is usually sufficient to hold it in place over the manhole opening.
  • suitable fastening struc ture may be provided if a more positive hold down is desired.
  • a first or pressure relief valve member 38 is secured to the semicircular segment 22 of the cover plate 20 for relieving internal pressure inside the manhole l2.
  • a second or vacuum relief valve 40 is secured to the semicircular segment 24 of the cover plate 20 for relieving vacuum that develops inside the manhole 12.
  • the valve members 38, 40 function to relieve pressure and vacuum inside the manhole l2 when the pressure therein exceeds a predeterminedamount, such as, for example, five pounds per square inch above atmospheric pressure, and also to relieve vacuum in the manhole when it exceeds a predetermined amount, such as, for example, five pounds per square inch below atmospheric pressure.
  • FIGS. 3 and 4 illustrate another movable closure assembly 50 according to the present invention wherein a standardmanhole cover or lid 52 is slightly modified so as to carry a pressure relief valve member 54 and a vacuum relief valve member 56.
  • a pair of annular housings 58 are formed on the underside of the .cover 52 directly below passageways 60 formed in the cover 52.
  • the passageways 60 in the cover 52 provide communication between the up side of the cover 52 and the interior of the annular housings 58.
  • Each housing is sealed off at its lower end by a disc 62 which carries one of the valve members. Suitable fasteners such as 64 are provided for anchoring each disc to its respective annular housing 58.
  • the valve members 54, 56 function to relieve pressure and vacuum inside the manhole 12 when these variables exceed predetermined amounts. The details of the valve members 54, 56 are explained below in conjunction with FIGS. 8 and 9.
  • the manhole cover 52 functions as a cover plate for sealing off the manhole opening. Sealing material or a suitable gasket 66 is located between the lower peripheral edge portion of the cover 52 and the supporting flange 18 of the annular manhole frame 14. 7
  • the pressure valve 38 includes a stationary valve body 70 fabricated from aluminum, for example, having a valve seat portion 72.
  • the valve body 70 is secured to-the cover plate 20 by a locking ring arrangement 73.
  • the valve 38 also includes a movable valve element 74 and valve stem 76, and a coil spring 78 that reacts between the valve stem and the stationary valve body 70.
  • Passageways 80 are located in the valve body for providing communication between the up side and down side of the cover plate 20 when the valve is open.
  • the passageways 80 in' the pressure relief valve 38 are tapered with an increasing cross sectional area in the downward direction.
  • the tapered passageways provide a self-cleaning function, as explained more fully blow.
  • the movable valve element 74 carries a ring of resilient material 82 which engages the seat portion 72 of the valve body 70 when the valve member is closed.
  • the valve seat portion 72 has a circular sharpened edge 84 that provides an air tight seal with the resilient ring 82 carried by the movable valve element 74 when the valve is closed.
  • slit or other material usually accumulates on top of the cover plate 20 and may reach a height close to the height of the valve seat 72. In such instances the sharpened edge 84 cuts through the silt to effectively close the valve when closure of the valve is desired.
  • Coil spring 78 is designed to hold the movable valve element 74 against the stationary valve body until the force acting upon the underside of the movable valve element is greater than the force of the coil spring 78 which acts in an opposite direction.
  • the force generated by that pressure on the movable valve element 74 is sufficient to urge the valve element in an upward direction to thereby relieve the pressure inside the manhole.
  • the vacuum relief valve 40 is practically identical to the pressure relief valve 38 except for its orientation. Additionally, the passageways in the stationary valve body of the vacuum relief valve 40 are tapered in an opposite direction relative to the movable valve element 74. Thus, the vacuum relief valve 40 has the same self-cleaning characteristics as the pressure relief valve even though the vacuum valve is oriented so that the movable valve element 74 is on the down side of the cover plate 20.
  • valve members 54, 56 associated with the embodiment of the invention specifically illustrated in FIGS. 3 and 4, are shown in detail in FIGS. 8 and 9.
  • the pressure relief valve 54 is identical to the vacuum relief valve 56 except that the movable valve element of the pressure relief valve moves in an upward direction when the valve is opened while the valve element of the vacuum relief valve moves in a downward direction when the valve is opened.
  • the valve 54 includes a stationary valve body 90 secured to the disc 62 of the cover plate assembly 50, as shown in FIG. 8. Sealing material 92 provides an air tight seal between the body 90 and the disc 62. Passageways 94 are located in the body 90 for providing communication between the up side and down side of the manhole closure assembly when the valve is opened.
  • a movable valve element 96 secured to a valve stem 98 moves away from the valve seat 100 of the body 90 when the force on the lower surface of the valve element 96 is greater than the force generated by the coil spring 102.
  • the coil spring 102 reacts between a stationary spring seat 104'and the movable valve stem 98.
  • the movable valve element 96 carries a ring of resilient material 106 that engages the seat 100 of the valve body when the valve is closed.
  • Each of the embodiments of the present invention provides a manhole closure assembly for sealing off the opening of a manhole construction that leads to a sewerage system.
  • the closure prevents storm and drainage water from emptying into the manhole. Excessive pressure inside the manhole is readily relieved when it exceeds a predetermined amount. Similarly, vacuum build-ups inside the manhole are relieved by a suitable vacuum relief.
  • a manhole closure assembly for preventing drainage and storm water from emptying into a manhole opening and an annular manhole frame surrounding the upper portion of the manhole
  • the manhole frame including an upper lid supporting flange and a lower flange for supporting the manhole closure assembly
  • the closure assembly including a cover plate supported by the'lower flange of the manhole frame in covering relationship over the manhole opening, the cover plate including a pair of substantially semicircular segments supported along their arcuate edge portions by the lower flange of the manhole frame, means for connecting the semicircular segments together along their diametral edge portions, a first valve member secured to the cover plate constructed and arranged to relieve pressure inside the manhole when the pressure therein exceeds a predetermined amount, and a second valve member secured to the plate constructed and arranged to relieve vacuum inside the manhole when the vacuum therein exceeds a predetermined amount.
  • first and second valve members each comprise a stationary valve body having at least one passageway therein that provides communication between the up side and down side of the cover plate when the valve member is open, and each passageway having a taper with the upper open end thereof smaller than the lower open end thereof.

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  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Sewage (AREA)

Abstract

Manhole closure assembly primarily prevents drainage and storm water from emptying into manhole leading to sewerage system. Closure assembly comprises cover plate sealing off manhole opening. First valve is secured to cover plate for relieving pressure inside manhole when pressure therein exceeds predetermined amount, and second valve member is secured to cover plate for relieving vacuum inside manhole when vacuum therein exceeds predetermined amount.

Description

United States Patent [191 Campagna 51 Jan. 23, 1973 [54] MANHOLE CLOSURE ASSEMBLY WITH VALVE RELIEF MEANS [75] Inventor: Benjamin J. Campagna, Newark,
Del.
[73] Assignees: Benjamin J. Compagna, Newark; Eugene J. Truono, Wilmington, Del.
22 Filed: Nov. 13,1970
21 Appl.No.: 89,301
UNITED STATES PATENTS 2,518,533 8/1950 Kieber ..l37/493.8 1,685,750 9/1928 Pfau et al. ....l37/493.8 1,099,073 6/1914 Moir ....l37/493.8
576,253 2/1897 Bingham ..94/37 579,864 3/1897 Moore et 31..... ....94/34 1,83 7,916 12/1931 Michelman ....94/34 3,308,727 3/1967 Hurt, Jr ....94/34 2,009,132 7/1935 Gehris ..94/35 1,153,051 9/1915 Fairhurst ..137/493.8
1,630,557 5/1927 Woodrow ..94/34 3,039,232 6/1962 Dunn .1 ..52/495 2,599,622 7/1952 Folmsbee ..137/54l 507,636 10/1893 Schneider..... 137/4938 3,267,631 8/1966 Hammitt ..52/495 3,192,671 7/1965 Smith ..52/495 3,001,537 9/1961 Shepherd ....l37l533.29 3,288,167 11/1966 Gibson ..137/541 144,844 11/1873 Campfield et a1. ..137/541 FQREIGN PATENTS OR APPLICATIONS 336,437 10/1930 GreatBritain ..94/34 Primary Examiner-Frank L. Abbott Assistant Examiner-Leslie A. Braun Atmmey-Connolly and Hutz ABSTRACT Manhole closure assembly primarily prevents drainage and storm water from emptying into manhole leading to sewerage system. Closure assembly comprises cover plate sealing off manhole opening. First valve is secured to cover'plate for relieving pressure inside manhole when pressure therein exceeds predetermined amount, and second valve member is secured to cover plate for relieving vacuum inside manhole when vacuum therein exceeds predetermined amount.
4 Claims, 9 Drawing Figures PATENTEDJAH 23 I975 3,712,009
SHEET 3 [IF 3 MANHOLE CLOSURE ASSEMBLY WITH VALVE RELIEF MEANS BACKGROUND OF THE INVENTION The present invention relates to a manhole closure assembly, and more particularly to a closure that prevents drainage and storm water from emptying into a manhole that leads to a sewerage system.
The primary reason for segregating sanitary or sewerage systems from systems designed to handle 1 storm and drainage water is an obvious one. Specifically, when drainage and storm water empties into a sanitary system the sewerage treatment plant must necessarily handle the storm water in addition to the sewage material. These conditions place an unnecessary burden on the sewage treatment facility. Standard frames and covers for manholes leading to sanitary or sewerage systems include cover constructions with passageways therein that enable storm water to empty into the sewerage system. The passageways in the standard cover constructions are provided for relieving internal pressure in the sanitary system as well as preventing vacuum build-ups in the system. It is impossible to simply plug up or otherwise eliminate the passageways in these covers since pressure developed inside the sanitary system could easily produce a force sufficient to blow the cover away from its seated position at the manhole opening. Also, unrelieved vacuum can also cause damage to the sanitary systems.
With an over designed sewerage system and/or an over capacity sewerage treatment plant, storm water draining into the sewerage system does not present any significant problems. However, with many systems capacity is now 100 percent, and 40 percent of this capacity is the direct result of storm and drainage water. Storm water volume draining into sewerage systems is much more significant today than it was many years ago, and the key factor is that today there is significantly less impervious area than there was several years ago. This factor is due to larger street areas that collect more drainage water as well as smaller building lots which cut down on the amount of overall impervious area. These factors have significantly contributed to the problem of overtaxing present sanitary systems. By significantly preve'nting storm and drainage water from emptying into sanitary and sewerage systems, existing systems can easily handle an additional 60 percent sewerage capacity.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a manhole closure assembly that effectively and easily seals off a manhole opening in an efficient and highly economical manner to thereby prevent drainage and stem water from emptying into the manhole.
Another object of the present invention is to provide a highly efficient and easy to follow method for preventing drainage and storm water from emptying into a manhole.
In accordance with the present invention a manhole closure assembly is provided for primarily preventing drainage and storm water from emptying into a manhole opening covered by the closure. The closure assembly comprises a cover plate sealing off the manhole opening with a first valve member secured to the plate arranged to relieve pressure inside the manhole when the pressure therein exceeds a predetermined amount. A second valve member also secured to the plate is arranged to relieve vacuum inside the manhole when the vacuum therein exceeds a predetermined amount.
In one embodiment of the present invention the cover plate comprises a pair of semicircular segments, and a connector strip seals and connects the semicircular segments together along their diametral edges. Preferably, the connector strip has a substantially I- shaped cross section. One valve member is secured to one of the semicircular segments of the cover plate while the other valve member is secured to the second semicircular segment of the plate.
In another aspect of the present invention the manhole closure is in combination with an annular manhole frame surrounding the upper portion of the manhole and anchored thereto. The annular manhole frame has an internal inwardly directed flange that supports the cover plate in sealing relationship over the manhole opening by engaging the arcuate edges of the semicircular segmentsof the cover plate and the ends of the connector strip. Sealing material is between the in wardly directed supporting flange of the manhole frame and the arcuate edges of the semicircular segments of the cover plate.
Preferably, the valve members of the present invention each comprise a stationary valve body having at least one passageway therein that provides communication between the up side and down side of the cover plate when the valve member is open. Each passageway has a taper with the upper open end thereof smaller than the lower open end thereof. Specifically, each valve member includes a valve body with a seat portion, a movable valve element and stem, and a biasing device between the valve stem and the valve body normally urging the valve element against the seat portion of the valve body. The valve element remains seated until the force acting upon the movable valve element in the direction opposite the force generated by the biasing device is greater than the force of the biasing device. When this condition occurs the movable valve element moves away from the seat portion of the valve body to open the valve member. In one valve member of the present invention the seat portion includes a substantially circular sharpened edge that engages the movable valve element. A ring of resilient material is carried by the movable valve element, and the ring is adapted to be engaged by the sharpened edge of the valvebody when the valve member is closed.-
The cover plate may comprise a one piece circular segment with a pair of spaced apart housings fixed to the underside thereof. The valve members are secured to the housings with one valve member associated with each housing. Passageways are located in the cover plate directly over each housing for providing communication between the up side of the cover plate and the interior of the housings.
BRIEF DESCRIPTION OF THE DRAWING Novel features and advantages of the present invention in addition to those mentioned above will become FIG. 2 is a sectional view taken along line 22 of FIG. 1;
FIG. 3 is a top plan view of another embodiment of the present invention;
FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;
FIG. 5 is a side elevational view of a valve member according to the present invention;
FIG. 6 is a bottom plan view of the valve member shown in FIG. 5;
FIG. 7 is a sectional view taken along line 7-7 of FIG. 6 with the valve member in its open position;
FIG. 8 is a side elevational view of another valve member according to the present invention with portions broken away to show detail and with the movable valve element shown in its unseated position inphantom outline; and
FIG. 9 is a bottom plan view of the valve member shown in FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION Referring in more particularity to the drawing, FIGS. 1 and 2 illustrate a manhole closure assembly 10 for primarily preventing drainage and storm water from emptying into a manhole 12 that leads to a sewerage system. As is well known, the upper end of most manhole constructions is surrounded by an annular manhole frame 14 embedded in a road bed 16 or similar surface construction. The annular manhole frame has an upper inwardly directed flange 18 for supporting a standard manhole cover or lid (not shown). The manhole lid has passageways therein, as is well known.
The manhole cover assembly 10 of the present invention comprises a cover plate 20 fabricated from rigid metal or similar material including a pair of semicircular segments 22, 24 and a connector strip or bar 26 that seals, supports and connects the semicircular segments together along their diametral edges 28. The bar 26 may also be constructed of rigid metal and has an I- shaped cross section. As shown in FIG. 2, the annular manhole frame 14 has a lower inwardly directed flange 30 that supports the arcuate edges 32 of the semicircular segments 22, 24 of the cover plate 20. The flange 30 also supports the ends 34 of the connector strip 26. The two piece construction of the cover plate 20 enables the plate to be easily positioned in sealing relationship over the manhole opening. Caulking or other suitable sealing material 36 is located between the flange 30 and the arcuate edges of the cover plate 20. Sealing material is also located at the juncture between the diametral edges 28 and the connector strip 26 to provide an air tight seal of the cover plate over the-manhole opening. The weight of. the manhole cover assembly is usually sufficient to hold it in place over the manhole opening. However, suitable fastening struc ture may be provided if a more positive hold down is desired.
A first or pressure relief valve member 38 is secured to the semicircular segment 22 of the cover plate 20 for relieving internal pressure inside the manhole l2. Additionally, a second or vacuum relief valve 40 is secured to the semicircular segment 24 of the cover plate 20 for relieving vacuum that develops inside the manhole 12. As explained more fully below in conjunction with the details of FIGS. 5-7, the valve members 38, 40 function to relieve pressure and vacuum inside the manhole l2 when the pressure therein exceeds a predeterminedamount, such as, for example, five pounds per square inch above atmospheric pressure, and also to relieve vacuum in the manhole when it exceeds a predetermined amount, such as, for example, five pounds per square inch below atmospheric pressure.
FIGS. 3 and 4 illustrate another movable closure assembly 50 according to the present invention wherein a standardmanhole cover or lid 52 is slightly modified so as to carry a pressure relief valve member 54 and a vacuum relief valve member 56. In this regard, a pair of annular housings 58 are formed on the underside of the .cover 52 directly below passageways 60 formed in the cover 52. As is clear from FIGS. 3 and 4, the passageways 60 in the cover 52 provide communication between the up side of the cover 52 and the interior of the annular housings 58. Each housing is sealed off at its lower end by a disc 62 which carries one of the valve members. Suitable fasteners such as 64 are provided for anchoring each disc to its respective annular housing 58. The valve members 54, 56 function to relieve pressure and vacuum inside the manhole 12 when these variables exceed predetermined amounts. The details of the valve members 54, 56 are explained below in conjunction with FIGS. 8 and 9. The manhole cover 52 functions as a cover plate for sealing off the manhole opening. Sealing material or a suitable gasket 66 is located between the lower peripheral edge portion of the cover 52 and the supporting flange 18 of the annular manhole frame 14. 7
Referring now to FIGS. 5-7, the details of the valve member 38 are shown it being understood that the vacuum relief valve member 40 is substantially the same as valve 38 except that the vacuum valve 40 opens in a downward direction to relieve vacuum while the pressure valve 38 moves in an upward direction to relieve pressure. The pressure valve 38 includes a stationary valve body 70 fabricated from aluminum, for example, having a valve seat portion 72. The valve body 70 is secured to-the cover plate 20 by a locking ring arrangement 73. The valve 38 also includes a movable valve element 74 and valve stem 76, and a coil spring 78 that reacts between the valve stem and the stationary valve body 70. Passageways 80 are located in the valve body for providing communication between the up side and down side of the cover plate 20 when the valve is open. The passageways 80 in' the pressure relief valve 38 are tapered with an increasing cross sectional area in the downward direction. The tapered passageways provide a self-cleaning function, as explained more fully blow. The movable valve element 74 carries a ring of resilient material 82 which engages the seat portion 72 of the valve body 70 when the valve member is closed. As shown best in FIG. 7, the valve seat portion 72 has a circular sharpened edge 84 that provides an air tight seal with the resilient ring 82 carried by the movable valve element 74 when the valve is closed. Additionally, slit or other material usually accumulates on top of the cover plate 20 and may reach a height close to the height of the valve seat 72. In such instances the sharpened edge 84 cuts through the silt to effectively close the valve when closure of the valve is desired.
Coil spring 78 is designed to hold the movable valve element 74 against the stationary valve body until the force acting upon the underside of the movable valve element is greater than the force of the coil spring 78 which acts in an opposite direction. Thus, when the pressure inside the manhole l2 exceeds 5 pounds per square inch, for example, the force generated by that pressure on the movable valve element 74 is sufficient to urge the valve element in an upward direction to thereby relieve the pressure inside the manhole. When the valve opens water, slit, and silt, foreign material which accumulates on top of the cover plate is flushed through the passageways 80 before the valve 38 closes. The tapered configuration of the passageways 80 functions to assist in maintaining them free of obstructions.
As mentioned above, the vacuum relief valve 40 is practically identical to the pressure relief valve 38 except for its orientation. Additionally, the passageways in the stationary valve body of the vacuum relief valve 40 are tapered in an opposite direction relative to the movable valve element 74. Thus, the vacuum relief valve 40 has the same self-cleaning characteristics as the pressure relief valve even though the vacuum valve is oriented so that the movable valve element 74 is on the down side of the cover plate 20. When the downward pull on the exterior of the movable valve element 74 of the vacuum relief valve 40 exceeds the force generated by the coil spring 78, the valve is pulled open to thereby relieve the vacuum generated inside the manhole 12. When the force of the coil spring exceeds the downward pull on the movable valve element 74 the vacuum relief valve is snapped closed.
The valve members 54, 56 associated with the embodiment of the invention specifically illustrated in FIGS. 3 and 4, are shown in detail in FIGS. 8 and 9. In the manhole closure assembly 50, the pressure relief valve 54 is identical to the vacuum relief valve 56 except that the movable valve element of the pressure relief valve moves in an upward direction when the valve is opened while the valve element of the vacuum relief valve moves in a downward direction when the valve is opened. The valve 54 includes a stationary valve body 90 secured to the disc 62 of the cover plate assembly 50, as shown in FIG. 8. Sealing material 92 provides an air tight seal between the body 90 and the disc 62. Passageways 94 are located in the body 90 for providing communication between the up side and down side of the manhole closure assembly when the valve is opened. A movable valve element 96 secured to a valve stem 98 moves away from the valve seat 100 of the body 90 when the force on the lower surface of the valve element 96 is greater than the force generated by the coil spring 102. As is clear, the coil spring 102 reacts between a stationary spring seat 104'and the movable valve stem 98. The movable valve element 96 carries a ring of resilient material 106 that engages the seat 100 of the valve body when the valve is closed.
Each of the embodiments of the present invention provides a manhole closure assembly for sealing off the opening of a manhole construction that leads to a sewerage system. The closure prevents storm and drainage water from emptying into the manhole. Excessive pressure inside the manhole is readily relieved when it exceeds a predetermined amount. Similarly, vacuum build-ups inside the manhole are relieved by a suitable vacuum relief.
What is claimed is:
l. The combination of a manhole closure assembly for preventing drainage and storm water from emptying into a manhole opening and an annular manhole frame surrounding the upper portion of the manhole, the manhole frame including an upper lid supporting flange and a lower flange for supporting the manhole closure assembly, and the closure assembly including a cover plate supported by the'lower flange of the manhole frame in covering relationship over the manhole opening, the cover plate including a pair of substantially semicircular segments supported along their arcuate edge portions by the lower flange of the manhole frame, means for connecting the semicircular segments together along their diametral edge portions, a first valve member secured to the cover plate constructed and arranged to relieve pressure inside the manhole when the pressure therein exceeds a predetermined amount, and a second valve member secured to the plate constructed and arranged to relieve vacuum inside the manhole when the vacuum therein exceeds a predetermined amount.
2. The combination of claim 1 in which the first and second valve members each comprise a stationary valve body having at least one passageway therein that provides communication between the up side and down side of the cover plate when the valve member is open, and each passageway having a taper with the upper open end thereof smaller than the lower open end thereof.
3. The combination of claim 1 in which the uppermost ends of the first and second valve members are elevated above the cover plate.
4. The combination of claim 1 in which the means for connecting the semicircular segments together includes a connector strip supported at its ends by the lower flange of the manhole frame and securing the semicircular segments together along their diametral edge portions.
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Claims (4)

1. The combination of a manhole closure assembly for preventing drainage and storm water from emptying into a manhole opening and an annular manhole frame surrounding the upper portion of the manhole, the manhole frame including an upper lid supporting flange and a lower flange for supporting the manhole closure assembly, and the closure assembly including a cover plate supported by the lower flange of the manhole frame in covering relationship over the manhole opening, the cover plate including a pair of substantially semicircular segments supported along their arcuate edge portions by the lower flange of the manhole frame, means for connecting the semicircular segments together along their diametral edge portions, a first valve member secured to the cover plate constructed and arranged to relieve pressure inside the manhole when the pressure therein exceeds a predetermined amount, and a second valve member secured to the plate constructed and arranged to relieve vacuum inside the manhole when the vacuum therein exceeds a predetermined amount.
2. The combination of claim 1 in which the first and second valve members each comprise a stationary valve body having at least one passageway therein that provides communication between the up side and down side of the cover plate when the valve member is open, and each passageway having a taper with the upper open end thereof smaller than the lower open end thereof.
3. The combination of claim 1 in which the uppermost ends of the first and second valve members are elevated above the cover plate.
4. The combination of claim 1 in which the means for connecting the semicircular segments together includes a connector strip supported at its ends by the lower flange of the manhole frame and securing the semicircular segments together along their diametral edge portions.
US00089301A 1970-11-13 1970-11-13 Manhole closure assembly with valve relief means Expired - Lifetime US3712009A (en)

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Cited By (42)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969847A (en) * 1974-11-18 1976-07-20 Benjamin J. Campagna Combination manhole closure assembly and separate support ring
US3973856A (en) * 1975-06-17 1976-08-10 Joseph Gaglioti Manhole closure assembly
US3975870A (en) * 1974-09-05 1976-08-24 Hiromitsu Naka Floor hatch
US4030851A (en) * 1976-11-03 1977-06-21 Graybeal Walter C Manhole closure including a two-way pressure relief valve
US4067659A (en) * 1976-11-11 1978-01-10 Bes, Ltd. Manhole closure assembly
US4248546A (en) * 1979-06-27 1981-02-03 Danner Donald J Manhole ceiling tent
US4305478A (en) * 1980-07-07 1981-12-15 Geisinger Glen W Anchoring and rescue apparatus
US4305679A (en) * 1981-01-19 1981-12-15 Modi Arvind O Manhole sealing device
US4650365A (en) * 1985-05-28 1987-03-17 Frw Industries, Inc. Watertight manhole insert
US4649674A (en) * 1986-03-17 1987-03-17 Craig S. Gaul Drain hole seal with bottom bleeder
US4957389A (en) * 1989-09-05 1990-09-18 Neathery David L Method and apparatus for sealing manholes
US5028320A (en) * 1989-12-04 1991-07-02 Gaudin Carl J Sewer catch basin with gas seal for a petroleum refinery or chemical processing plant
US5062735A (en) * 1989-12-04 1991-11-05 Gaudin Carl J Self sealing domed sewer cover assembly
WO1992009753A1 (en) * 1990-11-26 1992-06-11 Horst Guggemos Cap for a shaft
US5318376A (en) * 1992-12-07 1994-06-07 Prescott Sr Everett J Manhole frame
US5333490A (en) * 1987-10-01 1994-08-02 Total Containment, Inc. Secondary containment system using flexible piping
USD383763S (en) * 1996-06-13 1997-09-16 Advanced Polymer Technology, Inc. Combined one-piece tank sump with integral dust cover
US5727351A (en) * 1993-05-26 1998-03-17 Neathery; David L. Manhole insert and tether and method
US5743673A (en) * 1994-08-04 1998-04-28 Bravo; Sergio M. Watertight sealing system with relief valve for manhole having a spill bucket
US5833392A (en) * 1996-06-11 1998-11-10 Advanced Polymer Technology, Inc. One-piece tank sump with integral dust cover
DE19740405A1 (en) * 1997-09-09 1999-03-25 Juergen Strebe Ventilated drain hatch
US5961155A (en) * 1996-07-11 1999-10-05 Advanced Polymer Technology, Inc. Flexible entry boot
US5966876A (en) * 1997-10-17 1999-10-19 Southwestern Packing & Seals Inc. Manhole insert and tether apparatus and method
US5967567A (en) * 1998-01-15 1999-10-19 Advanced Polymer Technology, Inc. Matingly engaged flexible entry boot
US6086117A (en) * 1998-05-05 2000-07-11 Advanced Polymer Technology, Inc. Double booted flexible entry boot
USD429735S (en) * 1998-07-23 2000-08-22 Advanced Polymer Technology, Inc. Integrally formed tank sump with lid
US6173997B1 (en) 1996-07-11 2001-01-16 Advanced Polymer Technology, Inc. Flexible entry boot
US6189717B1 (en) 1998-09-14 2001-02-20 Advanced Polymer Technology, Inc. Integrally formed tank sump with water resistant lid assembly
US6350081B1 (en) * 2000-07-25 2002-02-26 Department Of Water And Power City Of Los Angeles Manhole restraining system for venting out explosive gases in a manhole
US6464425B1 (en) 1999-07-16 2002-10-15 Robert F. Closkey Apparatus and method for minimizing liquid infiltration into subterranean openings
US6551015B1 (en) * 2000-07-25 2003-04-22 Department Of Water And Power City Of Los Angeles Method of and system for venting out buildup of explosive gases in a manhole
US20040040221A1 (en) * 2002-08-26 2004-03-04 Michael Airheart Molded manhole unit
US8714867B1 (en) 2012-12-13 2014-05-06 EJ USA, Inc. Explosion mitigating cover
US8784000B2 (en) 2012-12-13 2014-07-22 EJ USA, Inc. Explosion mitigating cover
US8851791B1 (en) 2013-09-11 2014-10-07 David Putnam Manhole cover venting and precipitation guarding devices
US9340948B2 (en) 2014-10-01 2016-05-17 EJ USA, Inc. Explosion mitigating vault
US9605403B1 (en) * 2015-06-02 2017-03-28 David Putnam Vented precipitation guarding manhole cover assemblies
GB2543597A (en) * 2015-05-27 2017-04-26 Carreg Construction Ltd Covers for voids
US9695569B1 (en) 2016-07-01 2017-07-04 Roger W. Knowles Manhole cover sealing device
US9784650B1 (en) 2015-05-21 2017-10-10 David L. Neathery Sewer gas sampling and analyzing devices and methods
US10344447B2 (en) * 2016-05-10 2019-07-09 TiteLids, Inc. Closure systems, debris caps, holder devices, and related technologies
US20210262188A1 (en) * 2020-02-24 2021-08-26 Objectvideo Labs, Llc Detecting and alleviating flooding and blocked storm sewers

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US576253A (en) * 1897-02-02 Manhole-cover
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US1153051A (en) * 1914-12-05 1915-09-07 William S Fairhurst Valve.
US1685750A (en) * 1924-12-26 1928-09-25 Allis Chalmers Mfg Co Control system
US1630557A (en) * 1925-12-19 1927-05-31 Woodrow Walter Joseph Cover for manholes
US1837916A (en) * 1927-09-09 1931-12-22 Michelman Nathan Weatherproof sidewalk door
GB336437A (en) * 1929-10-16 1930-10-16 Walter Needham Improvements in or relating to manhole, meter, hydrant, gulley and like covers and frames therefor
US2009132A (en) * 1932-11-10 1935-07-23 Joseph L Gehris Manhole construction
US2518533A (en) * 1945-10-18 1950-08-15 Western Electric Co Reel
US2599622A (en) * 1947-01-03 1952-06-10 American Car & Foundry Co Resilient seal safety valve
US3039232A (en) * 1959-07-06 1962-06-19 Harold S Dunn Connector for mounting roof forming panels
US3192671A (en) * 1961-04-10 1965-07-06 Us Stoneware Co Panel structures
US3267631A (en) * 1963-04-10 1966-08-23 Andrew B Hammitt Mounting means for sheet material
US3288167A (en) * 1964-02-05 1966-11-29 Textron Inc Relife valve
US3308727A (en) * 1964-04-08 1967-03-14 Central States Ind Supply Comp Support for manhole cover and the like

Cited By (50)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3975870A (en) * 1974-09-05 1976-08-24 Hiromitsu Naka Floor hatch
US3969847A (en) * 1974-11-18 1976-07-20 Benjamin J. Campagna Combination manhole closure assembly and separate support ring
US3973856A (en) * 1975-06-17 1976-08-10 Joseph Gaglioti Manhole closure assembly
US4030851A (en) * 1976-11-03 1977-06-21 Graybeal Walter C Manhole closure including a two-way pressure relief valve
US4067659A (en) * 1976-11-11 1978-01-10 Bes, Ltd. Manhole closure assembly
US4248546A (en) * 1979-06-27 1981-02-03 Danner Donald J Manhole ceiling tent
US4305478A (en) * 1980-07-07 1981-12-15 Geisinger Glen W Anchoring and rescue apparatus
US4305679A (en) * 1981-01-19 1981-12-15 Modi Arvind O Manhole sealing device
US4650365A (en) * 1985-05-28 1987-03-17 Frw Industries, Inc. Watertight manhole insert
US4649674A (en) * 1986-03-17 1987-03-17 Craig S. Gaul Drain hole seal with bottom bleeder
US5333490A (en) * 1987-10-01 1994-08-02 Total Containment, Inc. Secondary containment system using flexible piping
US4957389A (en) * 1989-09-05 1990-09-18 Neathery David L Method and apparatus for sealing manholes
US5028320A (en) * 1989-12-04 1991-07-02 Gaudin Carl J Sewer catch basin with gas seal for a petroleum refinery or chemical processing plant
US5062735A (en) * 1989-12-04 1991-11-05 Gaudin Carl J Self sealing domed sewer cover assembly
WO1992009753A1 (en) * 1990-11-26 1992-06-11 Horst Guggemos Cap for a shaft
US5401114A (en) * 1990-11-26 1995-03-28 Guggemos; Horst Manhole ventilation insert with duct shut-off device
US5318376A (en) * 1992-12-07 1994-06-07 Prescott Sr Everett J Manhole frame
US5727351A (en) * 1993-05-26 1998-03-17 Neathery; David L. Manhole insert and tether and method
US5743673A (en) * 1994-08-04 1998-04-28 Bravo; Sergio M. Watertight sealing system with relief valve for manhole having a spill bucket
US5833392A (en) * 1996-06-11 1998-11-10 Advanced Polymer Technology, Inc. One-piece tank sump with integral dust cover
US5988944A (en) * 1996-06-11 1999-11-23 Advanced Polymer Technology, Inc. One-piece tank sump with integral dust cover
USD383763S (en) * 1996-06-13 1997-09-16 Advanced Polymer Technology, Inc. Combined one-piece tank sump with integral dust cover
US5961155A (en) * 1996-07-11 1999-10-05 Advanced Polymer Technology, Inc. Flexible entry boot
US6612620B1 (en) 1996-07-11 2003-09-02 Advanced Polymer Technology, Inc. Flexible entry boot
US6173997B1 (en) 1996-07-11 2001-01-16 Advanced Polymer Technology, Inc. Flexible entry boot
DE19740405A1 (en) * 1997-09-09 1999-03-25 Juergen Strebe Ventilated drain hatch
DE19740405C2 (en) * 1997-09-09 1999-08-05 Juergen Strebe Sealing plug for ventilated manhole covers
US6145891A (en) * 1997-09-29 2000-11-14 Advanced Polymer Technology, Inc. Double booted flexible entry boot
US5966876A (en) * 1997-10-17 1999-10-19 Southwestern Packing & Seals Inc. Manhole insert and tether apparatus and method
US5967567A (en) * 1998-01-15 1999-10-19 Advanced Polymer Technology, Inc. Matingly engaged flexible entry boot
US6086117A (en) * 1998-05-05 2000-07-11 Advanced Polymer Technology, Inc. Double booted flexible entry boot
USD429735S (en) * 1998-07-23 2000-08-22 Advanced Polymer Technology, Inc. Integrally formed tank sump with lid
US6189717B1 (en) 1998-09-14 2001-02-20 Advanced Polymer Technology, Inc. Integrally formed tank sump with water resistant lid assembly
US6464425B1 (en) 1999-07-16 2002-10-15 Robert F. Closkey Apparatus and method for minimizing liquid infiltration into subterranean openings
US6743088B2 (en) 1999-07-16 2004-06-01 Robert F. Closkey Apparatus and method for minimizing liquid infiltration into subterranean openings
US6350081B1 (en) * 2000-07-25 2002-02-26 Department Of Water And Power City Of Los Angeles Manhole restraining system for venting out explosive gases in a manhole
US6551015B1 (en) * 2000-07-25 2003-04-22 Department Of Water And Power City Of Los Angeles Method of and system for venting out buildup of explosive gases in a manhole
US20040040221A1 (en) * 2002-08-26 2004-03-04 Michael Airheart Molded manhole unit
US8784000B2 (en) 2012-12-13 2014-07-22 EJ USA, Inc. Explosion mitigating cover
US8714867B1 (en) 2012-12-13 2014-05-06 EJ USA, Inc. Explosion mitigating cover
US8851791B1 (en) 2013-09-11 2014-10-07 David Putnam Manhole cover venting and precipitation guarding devices
US9340948B2 (en) 2014-10-01 2016-05-17 EJ USA, Inc. Explosion mitigating vault
US9784650B1 (en) 2015-05-21 2017-10-10 David L. Neathery Sewer gas sampling and analyzing devices and methods
GB2543597A (en) * 2015-05-27 2017-04-26 Carreg Construction Ltd Covers for voids
GB2543597B (en) * 2015-05-27 2021-01-20 Carreg Construction Ltd Covers for voids
US9605403B1 (en) * 2015-06-02 2017-03-28 David Putnam Vented precipitation guarding manhole cover assemblies
US10344447B2 (en) * 2016-05-10 2019-07-09 TiteLids, Inc. Closure systems, debris caps, holder devices, and related technologies
US9695569B1 (en) 2016-07-01 2017-07-04 Roger W. Knowles Manhole cover sealing device
US20210262188A1 (en) * 2020-02-24 2021-08-26 Objectvideo Labs, Llc Detecting and alleviating flooding and blocked storm sewers
US11920318B2 (en) * 2020-02-24 2024-03-05 Objectvideo Labs, Llc Detecting and alleviating flooding and blocked storm sewers

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Owner name: CAMPAGNA, BENJAMIN J., NEW CASTLE, NEWARK, DE.

Free format text: SAID ASSIGNEE IS APPOINTED AS ATTORNEY IN-FACT TO EFFECT THE TRANSFER AND SALE OF ANY INTEREST SAIDASSIGNOR MAY HAVE IN SAID PATENTS;ASSIGNOR:TRUONO, EUGENE J.;REEL/FRAME:003980/0855

Effective date: 19810115

Owner name: FORSROC INTERNATIONAL LIMITED, 285 LONG ACRE, NECH

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:CAMPAGNA, BENJAMIN J.;TRUONO, EUGENE J.;REEL/FRAME:003850/0790

Effective date: 19810115