CA2018863C - Concrete pipe adaptor - Google Patents
Concrete pipe adaptorInfo
- Publication number
- CA2018863C CA2018863C CA 2018863 CA2018863A CA2018863C CA 2018863 C CA2018863 C CA 2018863C CA 2018863 CA2018863 CA 2018863 CA 2018863 A CA2018863 A CA 2018863A CA 2018863 C CA2018863 C CA 2018863C
- Authority
- CA
- Canada
- Prior art keywords
- placing
- forms
- adaptor
- seal
- concrete
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Abstract
An adaptor (10) having a concrete cylindrical body (12) with an axial bore (14) having a directional twin seal (24) cast within the body (12) to project into the axial bore (14). The bore (14) has a maximum diameter at each end (16, 18) of the body (12) that decreases to a minimum diameter at the center of the bore (14) where the seal (24) is positioned. The method of constructing the adaptor (10) includes the steps of placing a lower form (44) on a support member (40); placing a seal (54) on the lower form (44); placing an upper form (46) on the seal (54); and placing an outer cylinder (42) around the upper and lower forms (44, 46) to create a space (58) into which liquid concrete is poured.
Description
CONCRET-E PIPE ADAPTOR
Technical Field The present invention pertains to pipe fittings and, more particularly, to a concrete pipe fitting for coupling plastic pipe to a concrete structure such as a 5 manhole, a pipe, or the like.
Background of the Invention Sewage and drainage systems typically use underground pipes to convey sewage, storm water, and other waste material to a treatment facility or waste disposal site. These pipes are routed through manholes at various locations.
1 Manholes are used to provide access to the system for cleaning and repair.
Manholes are also used when there is a change of grade or direction to maintain the proper flow of waste material.
In the past, sewage pipes have been formed of concrete. These concrete pipes were attached into the manhole and sealed in place with cement grout.
15 Because concrete pipes are porous, they frequently do not remain watertight. In addition, concrete pipes tend to fracture when improperly backfilled. Because ofpublic health concerns, regulations in many localities require that plastic or PVC
pipe be used instead of concrete, and that all pipe connections achieve some degree of watertightness.
The use of plastic pipe with concrete manholes makes it very difficult to obtain a proper seal where the two come together because of the incompatibility of plastic and concrete. In one ,~)r~posed method for overcoming this problem, aconcrete cylinder with an axial bore is formed and a gasket is then rolled inside the bore. In some instances, t~l ~asket i, he~d in position in the bore by cutting a 25 channel around the inside of tr,c~ bore and then rolling the gasket in place in the channel.
This method has several dlsadvantages. First, when the plastlc plpe ls backfllled wlth soll, the welght pushlng down on the pipe causes the plpe to crush the gasket at the bottom of the plpe, leavlng a gap between the top of the plpe and the gasket. Thls gap also occurs when the plpe ls not posltioned perpendlcular to the seal. In addltlon, the welght of the backflll causes movement of the plpe, whlch can crack the cyllnder. As a result, these cyllnders frequently fall to achieve or malntaln a watertlght connectlon. Furthermore, cuttlng a channel lnside the bore of the plpe requlres the use of carbon- or diamond-tlpped cuttlng tools. Thls type of machlning ls expenslve, tlme-consumlng, and can weaken the concrete. The present lnventlon ls dlrected to overcoming these drawbacks.
Summary of the Invention The present lnventlon provldes a method of constructlng an adaptor for connectlng plastlc plpe to a concrete structure such as a manhole, a plpe, or the llke, the method comprlslng the steps of: placlng an outer form on a support member; placlng a lower form on sald support member generally concentrlcally wlthln sald outer form, sald lower form havlng a top surface; placing a gasket on sald top surface of sald lower form so that flanges on sald gasket pro~ect outward toward said outer form; placlng an upper form on said gasket such that a space ls formed between sald outer form and sald upper and lower forms; and pourlng a llquld concrete mlxture lnto sald space.
The present lnvention also provldes a method of constructlng an adaptor for coupllng plastic pipe to a concrete structure comprlslng the following steps: placing a lower form having a top surface on a support member; placing a gasket on said top surface of said lower form; placing a top form on said gasket; placing an outer form generally concentrically around sald lower and upper forms on sald support member to clrcumscrlbe sald upper and lower forms to form a space around sald upper and lower forms lnto whlch a portlon of sald gasket pro~ects; and pouring llquld concrete into said space.
The present invention also provldes an adaptor for connecting pipe to a concrete structure, sald adaptor manufactured according to the steps of: constructing an inner form assembly including a first form, a second form positioned ad~acent said first form, and a seal located between said first and second forms wherein a portion of said seal is disposed between said first and second inner forms and a portion of seal pro~ects outward from said forms; placing an outer cylinder generally concentrically around said inner form assembly, said outer cylinder being separated from said inner form assembly to define a space therebetween; pouring a liquid concrete mlxture into said space and allowing sald mixture to harden so as to form a concrete body with an axial bore defined by sald first and second inner forms; and removing said outer cylinder and removing said inner forms so that said seal is partially embedded ln sald concrete body and at least partially extends lnto sald axial bore.
The flexlble seal is cast in the body to proiect into the axlal bore and may comprlse a one-plece flexlble seal that circumscrlbes the bore and has at least one flange pro~ectlng lnto the bore. Preferably, the seal ls a twln seal that has two flanges proiectlng into the bore.
Preferably, the inslde diarneter of the bore decreases from a rnaxirnurn diameter at each end of the bore to a mlnlmum dlameter at the center of the bore.
The space that clrcumscrlbes the lower and upper forms and into which a portion of the gasket pro~ects may contaln a relnforclng wlre mesh. The support rnernber ls preferably vibrated to settle the concrete mixture in the space.
The concrete mlxture may comprlse two parts of coarse sand, one part of flne sand, and one and one-half parts of cement.
As wlll be readily appreclated from the foregolng descrlptlon, the present lnvention provides an adaptor that is easily formed from concrete. Because the seal is cast into place, no additional labor or machining ls requlred to lnsert the seal or to cut a channel for retaining the seal. The cone-shaped internal bore allows for variation in the alignment of the pipe in the adaptor, thus avoiding cracking or fracturing of the pipe or adaptor if the pipe should shift position after backfilling. Furthermore, affixing the adaptor to a manhole with llquld cement and uslng a dlrectlonal twln seal achleves an alr and water tlght condltlon that exceeds all government requlrements.
- 3a -Brief DescrlPtion of the Drawings The foregolng and other features and advantages of the present lnventlon wlll be more readlly appreclated as the same becomes better understood by reference to the following detalled descriptlon when taken ln con~unctlon wlth the following drawlngs, whereln FIGURE 1 is a cross-sectlonal slde vlew of an adaptor formed ln accordance wlth the present lnventlon;
FIGURE 2 ls a top vlew of the adaptor of FIGURE l;
FIGURE 3 ls an isometrlc vlew in partlal cutaway illustratlng the form for maklng the adaptor of FIGURE l;
FIGURE 4 ls a slde vlew and partlal cross sectlon of the adaptor of FIGURE 4 coupllng a plastlc plpe to a manhole;
FIGURE 5 ls an isometrlc view in partial cutaway lllustratlng an alternatlve form for maklng the adaptor of FIGURE l; and FIGURE 6 ls a top vlew of a rlng mold used ln the form of FIGURE 5 for maklng the adaptor of thls lnventlon.
Detalled Descrlptlon of the Preferred Embodlment Referrlng lnitlally to FIGURES 1 and 2, an adaptor 10 ls shown havlng a generally cyllndrlcal body 12.
Preferably, the body 12 ls formed of concrete. A longltudlnal axlal bore 14 ls formed ln the body 12 that communlcates wlth flrst and second open ends 16 and 18. The lnslde and outside surfaces 20 and 22 of the - 3b -
Technical Field The present invention pertains to pipe fittings and, more particularly, to a concrete pipe fitting for coupling plastic pipe to a concrete structure such as a 5 manhole, a pipe, or the like.
Background of the Invention Sewage and drainage systems typically use underground pipes to convey sewage, storm water, and other waste material to a treatment facility or waste disposal site. These pipes are routed through manholes at various locations.
1 Manholes are used to provide access to the system for cleaning and repair.
Manholes are also used when there is a change of grade or direction to maintain the proper flow of waste material.
In the past, sewage pipes have been formed of concrete. These concrete pipes were attached into the manhole and sealed in place with cement grout.
15 Because concrete pipes are porous, they frequently do not remain watertight. In addition, concrete pipes tend to fracture when improperly backfilled. Because ofpublic health concerns, regulations in many localities require that plastic or PVC
pipe be used instead of concrete, and that all pipe connections achieve some degree of watertightness.
The use of plastic pipe with concrete manholes makes it very difficult to obtain a proper seal where the two come together because of the incompatibility of plastic and concrete. In one ,~)r~posed method for overcoming this problem, aconcrete cylinder with an axial bore is formed and a gasket is then rolled inside the bore. In some instances, t~l ~asket i, he~d in position in the bore by cutting a 25 channel around the inside of tr,c~ bore and then rolling the gasket in place in the channel.
This method has several dlsadvantages. First, when the plastlc plpe ls backfllled wlth soll, the welght pushlng down on the pipe causes the plpe to crush the gasket at the bottom of the plpe, leavlng a gap between the top of the plpe and the gasket. Thls gap also occurs when the plpe ls not posltioned perpendlcular to the seal. In addltlon, the welght of the backflll causes movement of the plpe, whlch can crack the cyllnder. As a result, these cyllnders frequently fall to achieve or malntaln a watertlght connectlon. Furthermore, cuttlng a channel lnside the bore of the plpe requlres the use of carbon- or diamond-tlpped cuttlng tools. Thls type of machlning ls expenslve, tlme-consumlng, and can weaken the concrete. The present lnventlon ls dlrected to overcoming these drawbacks.
Summary of the Invention The present lnventlon provldes a method of constructlng an adaptor for connectlng plastlc plpe to a concrete structure such as a manhole, a plpe, or the llke, the method comprlslng the steps of: placlng an outer form on a support member; placlng a lower form on sald support member generally concentrlcally wlthln sald outer form, sald lower form havlng a top surface; placing a gasket on sald top surface of sald lower form so that flanges on sald gasket pro~ect outward toward said outer form; placlng an upper form on said gasket such that a space ls formed between sald outer form and sald upper and lower forms; and pourlng a llquld concrete mlxture lnto sald space.
The present lnvention also provldes a method of constructlng an adaptor for coupllng plastic pipe to a concrete structure comprlslng the following steps: placing a lower form having a top surface on a support member; placing a gasket on said top surface of said lower form; placing a top form on said gasket; placing an outer form generally concentrically around sald lower and upper forms on sald support member to clrcumscrlbe sald upper and lower forms to form a space around sald upper and lower forms lnto whlch a portlon of sald gasket pro~ects; and pouring llquld concrete into said space.
The present invention also provldes an adaptor for connecting pipe to a concrete structure, sald adaptor manufactured according to the steps of: constructing an inner form assembly including a first form, a second form positioned ad~acent said first form, and a seal located between said first and second forms wherein a portion of said seal is disposed between said first and second inner forms and a portion of seal pro~ects outward from said forms; placing an outer cylinder generally concentrically around said inner form assembly, said outer cylinder being separated from said inner form assembly to define a space therebetween; pouring a liquid concrete mlxture into said space and allowing sald mixture to harden so as to form a concrete body with an axial bore defined by sald first and second inner forms; and removing said outer cylinder and removing said inner forms so that said seal is partially embedded ln sald concrete body and at least partially extends lnto sald axial bore.
The flexlble seal is cast in the body to proiect into the axlal bore and may comprlse a one-plece flexlble seal that circumscrlbes the bore and has at least one flange pro~ectlng lnto the bore. Preferably, the seal ls a twln seal that has two flanges proiectlng into the bore.
Preferably, the inslde diarneter of the bore decreases from a rnaxirnurn diameter at each end of the bore to a mlnlmum dlameter at the center of the bore.
The space that clrcumscrlbes the lower and upper forms and into which a portion of the gasket pro~ects may contaln a relnforclng wlre mesh. The support rnernber ls preferably vibrated to settle the concrete mixture in the space.
The concrete mlxture may comprlse two parts of coarse sand, one part of flne sand, and one and one-half parts of cement.
As wlll be readily appreclated from the foregolng descrlptlon, the present lnvention provides an adaptor that is easily formed from concrete. Because the seal is cast into place, no additional labor or machining ls requlred to lnsert the seal or to cut a channel for retaining the seal. The cone-shaped internal bore allows for variation in the alignment of the pipe in the adaptor, thus avoiding cracking or fracturing of the pipe or adaptor if the pipe should shift position after backfilling. Furthermore, affixing the adaptor to a manhole with llquld cement and uslng a dlrectlonal twln seal achleves an alr and water tlght condltlon that exceeds all government requlrements.
- 3a -Brief DescrlPtion of the Drawings The foregolng and other features and advantages of the present lnventlon wlll be more readlly appreclated as the same becomes better understood by reference to the following detalled descriptlon when taken ln con~unctlon wlth the following drawlngs, whereln FIGURE 1 is a cross-sectlonal slde vlew of an adaptor formed ln accordance wlth the present lnventlon;
FIGURE 2 ls a top vlew of the adaptor of FIGURE l;
FIGURE 3 ls an isometrlc vlew in partlal cutaway illustratlng the form for maklng the adaptor of FIGURE l;
FIGURE 4 ls a slde vlew and partlal cross sectlon of the adaptor of FIGURE 4 coupllng a plastlc plpe to a manhole;
FIGURE 5 ls an isometrlc view in partial cutaway lllustratlng an alternatlve form for maklng the adaptor of FIGURE l; and FIGURE 6 ls a top vlew of a rlng mold used ln the form of FIGURE 5 for maklng the adaptor of thls lnventlon.
Detalled Descrlptlon of the Preferred Embodlment Referrlng lnitlally to FIGURES 1 and 2, an adaptor 10 ls shown havlng a generally cyllndrlcal body 12.
Preferably, the body 12 ls formed of concrete. A longltudlnal axlal bore 14 ls formed ln the body 12 that communlcates wlth flrst and second open ends 16 and 18. The lnslde and outside surfaces 20 and 22 of the - 3b -
2~18863 body 12 have a smooth finish. A mesh screen 21 is formed in place inside the concrete body 12. As shown more clearly in FIGURE 1, the inside diameter of the bore 14 decreases from a maximum diameter at each end 16 and 18 to a minimum diameter at the center of the bore 14. Ideally, the taper is one-fourth inch diameter for every four inches of length.
Cast in place on the inside surface 22 is a flexible seal 24 that circumscribes the internal bore 14. The seal 24 shown in the representative embodiment is a directional twin-seal that is well known in the art and commercially available.
Consequently, it will not be described in detail. Briefly, the seal 24 is formed of neoprene or other similar pliable mat-~erial. Two flanges 26 and 28 project into the bore 14. Each flange 26 and 28 has two faces, a first face 30 that lies in a plane perpendicular to the longitudinal axis X of the bore 12, and a second face 32 that is inclined diagonally downward towards the first end 16 of the body 12 and the first face 32, as shown more clearly in FIGURE 1.
As such, a pipe inserted into the second end 18 will meet little resistance from the inclined second faces 32. However, the first faces 30 will resist movement of the pipe in the opposite direction, thus holding the pipe in place.
The seal 24 further includes a body portion 34 with two projecting lips 36 that are encased on the concrete body 12 for holding the seal 14 in place.
The adaptor 10 so described is constructed using a unique mold 38 shown in FIGURE 3. The mold 38 is comprised of a support base 40, a hollow outer cylinder 42, a lower form 44, and an upper form 46. The support member 40 has a central raised portion 48 that projects upward from the top surface 50 of the support member 40. The lower form 44 is a hollow, truncated cone having an inside diameter at its base that is sized to fit over the raised portion 48.
The lower form 44 has a top surface 52 on which rests a seal 54 having the same configuration as the seal 24 described above. Placed on top of the seal 54 is the upper form 46. The upper form 46 is also a truncated cone that is not necessarily hollow. When placed on the seal 54, the upper form 46 is inverted sothat the base of the form 46 is facing upward. The upper and lower forms 44 and 46 are constructed to have a one-fourth-inch taper to every four inches of.
height. A cone 56 is placed on or integrally formed with the upper form 46 for directing liquid cement around the upper form 46. The outer cylinder 42 is placed on the top surface 50 of the support member 40 to circumscribe the lower and upper forms 44 and 46, thus forming a space 58 between the lower and upper forms 44 and 46. A wire mesh screen 60 is placed in the space 58 to circumscribethe lower and upper forms 44 and 46.
The steps of the method of constructing the adaptor 10 include the step of first placing the lower form 44 on the support member 40. To insure the lower form 44 remains in place when the liquid concrete is poured, the base of the lower form 44 is fitted over the raised portion 48 on the support member 40. Next, theseal 54 is placed on the top surface 50 of the lower form 44 so that the flanges(not shown) of the seal project outward from the lower form 44. In other words, the flanges project into the space 58 that will be created. Next, the upper form 46 is inverted and placed on top of the seal 54. Finally, if the cone 56 isformed separate from the upper form 46, the cone 56 is then placed on the upper form 46. The outer cylinder 42 is then placed around the lower and upper forms 44 and 46 to create the space 58. If reinforcement is desired, the wire mesh screen 60 is then placed into the space 58 at a desired location. Finally, liquid concrete is then poured into the space 58 and allowed to harden. To insure the space 58 is free of air bubbles, the support member 40 may be vibrated with a shaker or other similar device that is well known in the art prior to hardening of the liquid concrete.
The support member 40, the outer cylinder 42, and the upper and lower forms 44 and 46 may be constructed of wood, metal, plastic, cardboard, or other suitable material. The reinforcing mesh 60 is commercially available and may be cut from a preformed roll and hooked together. It has been found that a mesh of 1" x 2" has been suitable for this application. The mixture of the liquid concrete that has been found to be most suitable for the present invention consists of two parts coarse sand, one part fine sand, and one and one-half parts cement. This creates smooth surfaces on the body 12 for a better fit and unrestricted water flow.
Although the steps of the method of the present invention have been described in a certain order, it is to be understood that they may be performed in other orders without departing from the spirit and scope of the present invention. For instance, the outer cylinder 42 may be placed on the support member 40 before or after the lower and upper forms 44 and 46 are in place.
Similarly, the screen mesh 60 may be placed on the support member 40 before or after the outer cylinder 42 and the lower and upper forms 44 and 46. However, toinsure proper spacing between the outer shell 42, the wire mesh 60, and the upper and lower forms 44 and 46, it is preferable that at least the lower form 44 be placed on the support member 40 first. However, this may not be required if positioning tabs are placed on the support member 40 to locate the position of the outer cylinder 42 and the wire mesh 60. Consequently, it is to be understood that 2018~63 the method of constructing the present invention may be performed otherwise than as described specifically herein without departing from the spirit and scope of the invention.
Turning now to FIGURE 4, the adaptor 10 is shown in use coupling a plastic pipe 62 to a manhole 64. In most applications, the manhole 64 has preformed knockouts located at predetermined locations in its wall 66. These knockouts areremoved by workers to create an opening that is sized to receive the adaptor 10.The adaptor 10 is held in place in the manhole 64 by cement grout 68, as shown.
The adaptor 10 is positioned in the manhole 64 so that the directional seal 24 has the inclined faces inclined toward the manhole 64. As such, the plastic pipe 62 is easily inserted into the adaptor 10 and past the seal 24. The clearance 70 formed between the pipe 62 and the adaptor 10 by the cone-shaped bore 14 allows for variation in the directional orientation of the pipe 62 without destroying the watertight integrity of the seal 24.
An alternative method of manufacturing the adaptor 10 is described with respect to FIGURES 5 and 6. Form 38' is used as a mold to shape the adaptor 10 out of liquid concrete in a manner identical to that described in the first method of manufacture. Form 38' includes the support member 40 with raised portion 48 and outer cylinder 42 disclosed with respect to the first-described form 38.
Form 38' further includes a lower form 44' and an upper form 46' that are similarly shaped and perform the same general function as the first-described lower and upper forms 44 and 46, respectively.
A ring mold 74, secured between the lower and upper forms 44' and 46', is dimensioned to define a seating space 76 in the concrete body in which the flexible seal 24 is secured. Ring mold 74 is an O-ring formed out of reinforced rubber or other plastic material that has a sectional profile identical to the sectional profile of the seal body portion 34 secured in the concrete body 12.
Mounting bores 80 are formed in the mold 74 so that it can be secured to complementary mounting pins 82, shown in phantom, that extend from the lower and upper forms 44' and 46'. A handle 84, shown in phantom, is integrally formedto the inner surfaces of the mold 74 to provide a handhold for collapsing and withdrawing the mold.
If the ring mold 74 is formed out of plastic it may be desirable to provide the mold with a diagonal slit 86 as depicted in FIGURE 6 to facilitate the removal of the mold from finished work pieces. If the mold 74 is formed out of rubber or material with similar flexible properties, the mold can be a continuous ring.
According to this method of manufacture, the form 38' is initially assembled as in the first method of manufacture. The ring mold 74 is secured between the lower and upper forms 44' and 46'. The mesh screen 60, not shown in FIGURE 5 to simplify illustration of this embodiment of the invention, is placed in the 5 mold 38'. Concrete is then poured into a space 58' defined by the lower and upper forms 44' and 46', the mold 74, and the outer cylinder 42 to form the body 12.
After the concrete has hardened, the lower and upper forms 44' and 46' and the ring mold 74 are removed. The ring mold 74 is removed by collapsing the moldso that it is freed from the newly-defined seating space 76 and then withdrawing10 it from the bore 12. The flexible seal 24 is then secured into the seating space 76. When the seal 24 is secured into the seating space 76, epoxy or other suitable adhesive may be used to fasten the seal to the adaptor body 12.
The foregoing description has been limited to specific embodiments of the invention. It will be apparent, however, that variations and modifications may be 15 made to the invention, with the attainment of some or all of the advantages of this invention. For instance, the adaptor 10 may be formed to have other cross-sectional shapes other than cylindrical or circular, such as square, hexagonal, etc. In addition, pressure grouting and/or pressure molding can be used to fill the forms with cement grout. The wire mesh may be replaced with a fibrous material 20 that is added to the grout for strength. Moreover, the exact steps of manufacturing may similarly be modified without departing from the scope of the invention. For example, in some embodiments of the invention, it may be desirable to provide a metal mold formed of a number of arcuate members arranged to collapse inwardly so that after the seal seating space is formed, the 25 mold can be removed. Alternatively, the mold may comprise elements that are integral with the upper and lower forms, such as hingedly attached flaps, that are locked in place when the form is first assembled. Therefore, it is the object ofthe appended claims to cover all such variations and modifications as come within the true scope of the invention.
Cast in place on the inside surface 22 is a flexible seal 24 that circumscribes the internal bore 14. The seal 24 shown in the representative embodiment is a directional twin-seal that is well known in the art and commercially available.
Consequently, it will not be described in detail. Briefly, the seal 24 is formed of neoprene or other similar pliable mat-~erial. Two flanges 26 and 28 project into the bore 14. Each flange 26 and 28 has two faces, a first face 30 that lies in a plane perpendicular to the longitudinal axis X of the bore 12, and a second face 32 that is inclined diagonally downward towards the first end 16 of the body 12 and the first face 32, as shown more clearly in FIGURE 1.
As such, a pipe inserted into the second end 18 will meet little resistance from the inclined second faces 32. However, the first faces 30 will resist movement of the pipe in the opposite direction, thus holding the pipe in place.
The seal 24 further includes a body portion 34 with two projecting lips 36 that are encased on the concrete body 12 for holding the seal 14 in place.
The adaptor 10 so described is constructed using a unique mold 38 shown in FIGURE 3. The mold 38 is comprised of a support base 40, a hollow outer cylinder 42, a lower form 44, and an upper form 46. The support member 40 has a central raised portion 48 that projects upward from the top surface 50 of the support member 40. The lower form 44 is a hollow, truncated cone having an inside diameter at its base that is sized to fit over the raised portion 48.
The lower form 44 has a top surface 52 on which rests a seal 54 having the same configuration as the seal 24 described above. Placed on top of the seal 54 is the upper form 46. The upper form 46 is also a truncated cone that is not necessarily hollow. When placed on the seal 54, the upper form 46 is inverted sothat the base of the form 46 is facing upward. The upper and lower forms 44 and 46 are constructed to have a one-fourth-inch taper to every four inches of.
height. A cone 56 is placed on or integrally formed with the upper form 46 for directing liquid cement around the upper form 46. The outer cylinder 42 is placed on the top surface 50 of the support member 40 to circumscribe the lower and upper forms 44 and 46, thus forming a space 58 between the lower and upper forms 44 and 46. A wire mesh screen 60 is placed in the space 58 to circumscribethe lower and upper forms 44 and 46.
The steps of the method of constructing the adaptor 10 include the step of first placing the lower form 44 on the support member 40. To insure the lower form 44 remains in place when the liquid concrete is poured, the base of the lower form 44 is fitted over the raised portion 48 on the support member 40. Next, theseal 54 is placed on the top surface 50 of the lower form 44 so that the flanges(not shown) of the seal project outward from the lower form 44. In other words, the flanges project into the space 58 that will be created. Next, the upper form 46 is inverted and placed on top of the seal 54. Finally, if the cone 56 isformed separate from the upper form 46, the cone 56 is then placed on the upper form 46. The outer cylinder 42 is then placed around the lower and upper forms 44 and 46 to create the space 58. If reinforcement is desired, the wire mesh screen 60 is then placed into the space 58 at a desired location. Finally, liquid concrete is then poured into the space 58 and allowed to harden. To insure the space 58 is free of air bubbles, the support member 40 may be vibrated with a shaker or other similar device that is well known in the art prior to hardening of the liquid concrete.
The support member 40, the outer cylinder 42, and the upper and lower forms 44 and 46 may be constructed of wood, metal, plastic, cardboard, or other suitable material. The reinforcing mesh 60 is commercially available and may be cut from a preformed roll and hooked together. It has been found that a mesh of 1" x 2" has been suitable for this application. The mixture of the liquid concrete that has been found to be most suitable for the present invention consists of two parts coarse sand, one part fine sand, and one and one-half parts cement. This creates smooth surfaces on the body 12 for a better fit and unrestricted water flow.
Although the steps of the method of the present invention have been described in a certain order, it is to be understood that they may be performed in other orders without departing from the spirit and scope of the present invention. For instance, the outer cylinder 42 may be placed on the support member 40 before or after the lower and upper forms 44 and 46 are in place.
Similarly, the screen mesh 60 may be placed on the support member 40 before or after the outer cylinder 42 and the lower and upper forms 44 and 46. However, toinsure proper spacing between the outer shell 42, the wire mesh 60, and the upper and lower forms 44 and 46, it is preferable that at least the lower form 44 be placed on the support member 40 first. However, this may not be required if positioning tabs are placed on the support member 40 to locate the position of the outer cylinder 42 and the wire mesh 60. Consequently, it is to be understood that 2018~63 the method of constructing the present invention may be performed otherwise than as described specifically herein without departing from the spirit and scope of the invention.
Turning now to FIGURE 4, the adaptor 10 is shown in use coupling a plastic pipe 62 to a manhole 64. In most applications, the manhole 64 has preformed knockouts located at predetermined locations in its wall 66. These knockouts areremoved by workers to create an opening that is sized to receive the adaptor 10.The adaptor 10 is held in place in the manhole 64 by cement grout 68, as shown.
The adaptor 10 is positioned in the manhole 64 so that the directional seal 24 has the inclined faces inclined toward the manhole 64. As such, the plastic pipe 62 is easily inserted into the adaptor 10 and past the seal 24. The clearance 70 formed between the pipe 62 and the adaptor 10 by the cone-shaped bore 14 allows for variation in the directional orientation of the pipe 62 without destroying the watertight integrity of the seal 24.
An alternative method of manufacturing the adaptor 10 is described with respect to FIGURES 5 and 6. Form 38' is used as a mold to shape the adaptor 10 out of liquid concrete in a manner identical to that described in the first method of manufacture. Form 38' includes the support member 40 with raised portion 48 and outer cylinder 42 disclosed with respect to the first-described form 38.
Form 38' further includes a lower form 44' and an upper form 46' that are similarly shaped and perform the same general function as the first-described lower and upper forms 44 and 46, respectively.
A ring mold 74, secured between the lower and upper forms 44' and 46', is dimensioned to define a seating space 76 in the concrete body in which the flexible seal 24 is secured. Ring mold 74 is an O-ring formed out of reinforced rubber or other plastic material that has a sectional profile identical to the sectional profile of the seal body portion 34 secured in the concrete body 12.
Mounting bores 80 are formed in the mold 74 so that it can be secured to complementary mounting pins 82, shown in phantom, that extend from the lower and upper forms 44' and 46'. A handle 84, shown in phantom, is integrally formedto the inner surfaces of the mold 74 to provide a handhold for collapsing and withdrawing the mold.
If the ring mold 74 is formed out of plastic it may be desirable to provide the mold with a diagonal slit 86 as depicted in FIGURE 6 to facilitate the removal of the mold from finished work pieces. If the mold 74 is formed out of rubber or material with similar flexible properties, the mold can be a continuous ring.
According to this method of manufacture, the form 38' is initially assembled as in the first method of manufacture. The ring mold 74 is secured between the lower and upper forms 44' and 46'. The mesh screen 60, not shown in FIGURE 5 to simplify illustration of this embodiment of the invention, is placed in the 5 mold 38'. Concrete is then poured into a space 58' defined by the lower and upper forms 44' and 46', the mold 74, and the outer cylinder 42 to form the body 12.
After the concrete has hardened, the lower and upper forms 44' and 46' and the ring mold 74 are removed. The ring mold 74 is removed by collapsing the moldso that it is freed from the newly-defined seating space 76 and then withdrawing10 it from the bore 12. The flexible seal 24 is then secured into the seating space 76. When the seal 24 is secured into the seating space 76, epoxy or other suitable adhesive may be used to fasten the seal to the adaptor body 12.
The foregoing description has been limited to specific embodiments of the invention. It will be apparent, however, that variations and modifications may be 15 made to the invention, with the attainment of some or all of the advantages of this invention. For instance, the adaptor 10 may be formed to have other cross-sectional shapes other than cylindrical or circular, such as square, hexagonal, etc. In addition, pressure grouting and/or pressure molding can be used to fill the forms with cement grout. The wire mesh may be replaced with a fibrous material 20 that is added to the grout for strength. Moreover, the exact steps of manufacturing may similarly be modified without departing from the scope of the invention. For example, in some embodiments of the invention, it may be desirable to provide a metal mold formed of a number of arcuate members arranged to collapse inwardly so that after the seal seating space is formed, the 25 mold can be removed. Alternatively, the mold may comprise elements that are integral with the upper and lower forms, such as hingedly attached flaps, that are locked in place when the form is first assembled. Therefore, it is the object ofthe appended claims to cover all such variations and modifications as come within the true scope of the invention.
Claims (15)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method of constructing an adaptor for coupling plastic pipe to a concrete structure comprising the following steps:
placing a lower form having a top surface on a support member;
placing a gasket on said top surface of said lower form;
placing a top form on said gasket;
placing an outer form generally concentrically around said lower and upper forms on said support Member to circumscribe said upper and lower forms to form a space around said upper and lower forms into which a portion of said gasket projects; and pouring liquid concrete into said space.
placing a lower form having a top surface on a support member;
placing a gasket on said top surface of said lower form;
placing a top form on said gasket;
placing an outer form generally concentrically around said lower and upper forms on said support Member to circumscribe said upper and lower forms to form a space around said upper and lower forms into which a portion of said gasket projects; and pouring liquid concrete into said space.
2. The method of claim 1, further comprising the step of placing a reinforcing wire mesh inside said space.
3. The method of claim 1, further comprising the step of vibrating said support member to remove air bubbles from said concrete mixture.
4. A method of constructing the adaptor for coupling plastic pipe to a concrete structure such as a manhole, another pipe, or the like, the method comprising the steps of:
placing a lower form having a top surface on a support member;
placing a gasket on said top surface of said lower form so that flanges on said gasket project outside of said lower form;
placing an upper form on said gasket;
placing a reinforcing mesh around said upper and lower forms;
placing an outer form on said support member generally concentrically around said upper and lower forms to circumscribe said upper and lower forms to form a space between said outer form and said upper and lower forms into which said gasket projects; and filling said space with liquid concrete.
placing a lower form having a top surface on a support member;
placing a gasket on said top surface of said lower form so that flanges on said gasket project outside of said lower form;
placing an upper form on said gasket;
placing a reinforcing mesh around said upper and lower forms;
placing an outer form on said support member generally concentrically around said upper and lower forms to circumscribe said upper and lower forms to form a space between said outer form and said upper and lower forms into which said gasket projects; and filling said space with liquid concrete.
5. The method of claim 4, further comprising the step of vibrating said support member to settle said liquid concrete in said space.
6. The method of claim 4, further comprising the step of placing a reinforcing wire mesh in said space prior to pouring said liquid concrete mixture.
7. The method of claim 4, further comprising the step of vibrating said support member to settle said liquid concrete mixture in said space and to remove air bubbles from said liquid concrete mixture.
8. A method of constructing an adaptor for connecting plastic pipe to a concrete structure such as a manhole, a pipe, or the like, the method comprising the steps of:
placing an outer form on a support member;
placing a lower form on said support member generally concentrically within said outer form, said lower form having a top surface;
placing a gasket on said top surface of said lower form so that flanges on said gasket project outward toward said outer form;
placing an upper form on said gasket such that a space is formed between said outer form and said upper and lower forms; and pouring a liquid concrete mixture into said space.
placing an outer form on a support member;
placing a lower form on said support member generally concentrically within said outer form, said lower form having a top surface;
placing a gasket on said top surface of said lower form so that flanges on said gasket project outward toward said outer form;
placing an upper form on said gasket such that a space is formed between said outer form and said upper and lower forms; and pouring a liquid concrete mixture into said space.
g. An adaptor for connecting pipe to a concrete structure, said adaptor manufactured according to the steps of:
constructing an inner form assembly including a first form, a second form positioned adjacent said first form, and a seal located between said first and second forms wherein a portion of said seal is disposed between said first and second inner forms and a portion of seal projects outward from said forms;
placing an outer cylinder generally concentrically around said inner form assembly, said outer cylinder being separated from said inner form assembly to define a space therebetween;
pouring a liquid concrete mixture into said space and allowing said mixture to harden so as to form a concrete body with an axial bore defined by said first and second inner forms; and removing said outer cylinder and removing said inner forms so that said seal is partially embedded in said concrete body and at least partially extends into said axial bore.
constructing an inner form assembly including a first form, a second form positioned adjacent said first form, and a seal located between said first and second forms wherein a portion of said seal is disposed between said first and second inner forms and a portion of seal projects outward from said forms;
placing an outer cylinder generally concentrically around said inner form assembly, said outer cylinder being separated from said inner form assembly to define a space therebetween;
pouring a liquid concrete mixture into said space and allowing said mixture to harden so as to form a concrete body with an axial bore defined by said first and second inner forms; and removing said outer cylinder and removing said inner forms so that said seal is partially embedded in said concrete body and at least partially extends into said axial bore.
10. The adaptor of claim 9, wherein at least one of first and second inner forms is configured to define an outwardly extending taper in said concrete body axial bore, said taper having a minimum diameter adjacent said seal.
11. The adaptor of claim 10, wherein said inner forms are configured to define a taper in said concrete body axial bore so that said concrete body axial bore has an outwardly extending taper adjacent each side of said seal.
12. The adaptor of claim 9, wherein said seal has at least two flanges extending into said concrete body axial bore.
13. The adaptor of claim 12, wherein said inner forms are configured to define a taper in said concrete body axial bore so that said concrete body axial bore has an outwardly extending taper adjacent each side of said seal.
14. The adaptor of claim 9, wherein said seal includes at least one directional flange projecting into said concrete body axial bore and facilitates insertion of a pipe into said bore in one direction and resists movement of said pipe in the opposite direction.
15. The adaptor of claim 14, wherein said inner forms are configured to define a taper in said concrete body axial bore so that sald concrete body axial bore has an outwardly extending taper adjacent each side of said seal.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/365,956 US4997215A (en) | 1989-06-14 | 1989-06-14 | Concrete pipe adaptor and method of making |
| US07/365,956 | 1989-06-14 | ||
| US45061289A | 1989-12-13 | 1989-12-13 | |
| US07/450,612 | 1989-12-13 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2018863A1 CA2018863A1 (en) | 1990-12-14 |
| CA2018863C true CA2018863C (en) | 1996-12-10 |
Family
ID=27003173
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2018863 Expired - Fee Related CA2018863C (en) | 1989-06-14 | 1990-06-13 | Concrete pipe adaptor |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2018863C (en) |
-
1990
- 1990-06-13 CA CA 2018863 patent/CA2018863C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2018863A1 (en) | 1990-12-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5297817A (en) | Street compression closet flange | |
| US6581940B2 (en) | Concrete manhole connector gasket | |
| US5386669A (en) | Corrosion resistant leakproof plastic manhole system | |
| US3973783A (en) | Pipe joint sealing device | |
| US5336351A (en) | Method for connecting a pipe connector to a hard plastic pipe | |
| CA1073938A (en) | Molded pleated gasket | |
| US5437430A (en) | Method for preparing or repairing a machine foundation | |
| US7827665B2 (en) | Gasket and mandrel assembly for pipe joints | |
| US3523552A (en) | Passageway forming sleeve | |
| US3832438A (en) | Method of providing a gasket seal between sewer pipe and manhole opening | |
| US4964180A (en) | Shower strainer mounting assembly | |
| US5413307A (en) | Precast manhole invert forming | |
| US5360284A (en) | Precast concrete drain inlet | |
| US3874063A (en) | Method of pipe joint sealing | |
| CN207469307U (en) | A kind of gang form structure of the inspection shaft cast-in-place construction of town road pipeline | |
| CA2018863C (en) | Concrete pipe adaptor | |
| US4997215A (en) | Concrete pipe adaptor and method of making | |
| KR101566229B1 (en) | Manufacturing equipment for Manhole using various connecting pipe, manufacturing method for the same and connecting method for the manhole with a connecting pipe | |
| EP0687781A1 (en) | Joint structure and joint method for a concrete structure | |
| KR100415965B1 (en) | Built-up Mold for Preventing Pollution, and Manhole and Retaining Wall by Using the Same, and Method for Construction the Manhole and Retaining Wall | |
| CA2537637C (en) | Cast-in-place gasket for pipe joints | |
| US5806829A (en) | Concrete hole former | |
| KR100743594B1 (en) | manhole, manufacturing equipment for the same, assembling method for the same equipment, and manufacturing method using the same equipment | |
| EP0510043B1 (en) | Foundation and method preparing or reparing same | |
| EP3995638A1 (en) | Concrete sanitary sewer pipes and manholes featuring a protective plastic liner |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |