Abstract: A connector for joining two pieces of sheet metal together end-to-end. A second wall and a first wall define a first channel therebetween, into which a ledge extends, and which lockingly receives one piece of sheet metal, by virtue of at least one reverse button lock on a raw free end of the one piece of sheet metal snapingly engaging against the ledge. A third wall terminates in a free edge that is folded onto itself, and together with the first wall, defines a second channel therebetween that lockingly receives the other piece of sheet metal, by virtue of at least one reverse button lock on a raw free end of the other piece of sheet metal snapingly engaging against the folded free edge of the third wall.

Abstract: A register opening cover may be used to cover register openings until the register boot is installed in the register opening. During the installation of the register boot, the invention may be used to hold the register boot in place until the register boot is securely connected to the floor. After the register boot is installed, the cover forms an insulator around the register boot. One embodiment of the invention provides a register opening cover and register boot frame that can be configured to fit register boots of different sizes. Another embodiment of the invention provides a register opening cover that will support some of the weight of a worker who may step on the covered register opening.

Abstract: A fan duct assembly includes a fan duct (200), a panel (600), and a locking plate (700). One end of the fan duct defines a rectangular opening (204) with a peripheral flange (220). A pair of ribs (224) is formed on one side of the flange. A pair of L-shaped catches (602) is stamped from the panel. The catches abut against the ribs, to retain the side of the flange. The locking plate is attached to the panel opposite to the catches. The locking plate includes a base (710) and a vertical portion (720) extending from the base. An L-shaped resilient tab (730) is inclinedly stamped from the locking plate, to resiliently abut against the side of the fan duct and the flange. A pair of resilient feet (716) extends from opposite sides of the base, each foot having a free end portion resiliently abutting against the flange.

Abstract: A device for coupling tubular members including a sheet member having a first end and a second end where the first end and the second end are operatively arranged to overlap one another to form a substantially cylindrically shaped coupling, an abutment member mounted to the sheet member proximate the second end thereof, a male threaded member, a female member pivotably mounted proximate the first end of the sheet member and arranged for pivoting rotation about a pivot point, where the female member is arranged to threadably engage the threaded male member, and the male member is operatively arranged to abut the abutment member, wherein the male threaded member is operatively arranged to rotate in a first direction to abut the abutment member and expand the substantially cylindrically shaped coupling.

Abstract: The duct connector of the present invention preferably has a rectangular inlet and a round outlet. An intermediate passage is located between the rectangular inlet and the round outlet. Preferably, the intermediate passage provides a smooth transition that is substantially free from steps, sharp corners, breaks or facets, and acts to smoothly funnel airflow from the rectangular inlet to the round outlet. The intermediate passage preferably includes transitional surfaces that connect adjacent walls of the duct. Each transitional surface preferably provides a single smooth continuously curved surface connecting a side wall and an adjacent end wall along the intermediate passage. The smooth transition of the intermediate passage and the use of transitional surfaces as just described reduces turbulence and noise within the duct connector and results in greater fan or blower efficiency.

Abstract: The apparatus for joining and sealing conduits, includes edge trim, a sleeve, and a retaining element. The edge trim is shaped to mount upon and engage an end of a conduit. The sleeve extends between the conduits and at least partially surrounds the edge trim. The sleeve may be made of compressible material, such that when the retaining element surrounds a portion of the sleeve and the edge trim, the retaining element generally compresses the portion of the sleeve portion underlying the retaining element and displaces the sleeve material to expand on either side of the retaining element and limit movement of the retaining element. The method of joining and sealing conduits includes mounting the edge trim and a retaining element upon an end of a conduit, extending a sleeve between the conduits, and sliding the retaining element over the sleeve toward the end of the conduit.

Abstract: A duct assembly for transporting pressurized fluid therethrough. The assembly includes first and second duct sections. Each of the duct sections has sides extending between opposite ends. Each of the sides join an adjacent side and has a flange extending laterally outward from each end. The first and second sections are positioned in end-to-end relation so that the flanges extending outward from one of the ends of the first section face the flanges extending outward from one of the ends of the second section to define flange pairs. The assembly also includes a plurality of connector pairs. Each of the connector pairs are positioned at one of the ends of the duct sections. Each of the connector pairs includes a first connector spanning adjacent flanges of the first duct section and a second connector spanning adjacent flanges of the second duct section.

Abstract: A bellows for a compensator as an elastic connection between two duct connection pieces or flange frames arranged from each other in the longitudinal direction is presented. The bellows contains a cavity arrangement between an outer wall, an inner wall, and curved sections at each end of the outer and inner walls. The outer wall, inner wall and curved sections are continuously connected. The cavity arrangement between the outer wall and the inner wall is designed as a single-chamber cavity. The single-chamber cavity between the outer wall and the inner wall is formed in a manner such that it is free from connecting webs. The material of the bellows is flexible.

Abstract: The present invention provides a transitional telescoping plenum apparatus that is intended to facilitate the interconnection of HVAC equipment to duct systems. The unit expands in length, width and height directions, and is composed of modular tier sections. Each modular tier includes at least four corner sections, with each corner section being interleaved with two adjacent corner sections to complete a single modular tier. Each modular tier includes a tier-connecting flange that communicates with a tier-connecting flange on another modular tier, such that the modular tiers can be interconnected to form a finished transitional telescoping plenum apparatus. Clips are also taught for connecting modular tiers to each other.

Abstract: A substantially airtight ducting enclosure is provided for a heating, ventilation, and/or air conditioning system. The enclosure, which may be a register box for return air or supply air, has a body formed from at least one planar sheet, the body having an inlet and an outlet. At least one of the inlet and the outlet is formed by folding corners of the planar sheet to form planar sides that lie in intersecting planes. The enclosure is then mounted to a surface of an interior area of a structure, and connected to ducts for communicating air between the interior area and a central air-handler unit.

Abstract: A flanged coupling ring for a duct element has a mounting section configured to be mounted or a connection portion of the duct element, and flange means extending outwards from the mounting section. The flange means has, along its periphery, flanged coupling portions for connecting two duct elements, each of which is provided with a coupling ring, by means of external coupling means configured to engage with the flanged coupling portions.

Abstract: A self-adhesive gasket having a pressure sensitive adhesive on one side or on both sides can be used in place of plumbers putty to seal sinks to countertops, faucets to sinks, and strainers and pop ups to sinks and tubs. The gasket is preferably preformed from a flexible cellular plastic, preferably a closed cell urethane foam. The gasket may be used in a multitude of plumbing application to form a liquid seal.

Abstract: A device for coupling tubular members including a sheet member having a first end and a second end where the first end and the second end are operatively arranged to overlap one another to form a substantially cylindrically shaped coupling, an abutment member mounted to the sheet member proximate the second end thereof, a male threaded member, a female member pivotably mounted proximate the first end of the sheet member and arranged for pivoting rotation about a pivot point, where the female member is arranged to threadably engage the threaded male member, and the male member is operatively arranged to abut the abutment member, wherein the male threaded member is operatively arranged to rotate in a first direction to abut the abutment member and expand the substantially cylindrically shaped coupling.

Abstract: A pipe boot having a vertical portion adapted to surround a predetermined portion of the pipe to be covered, the vertical portion having a top end and a bottom end, wherein the top end has a top opening and wherein the bottom end has a bottom opening; a base portion, wherein the base portion is connected to a bottom edge of the vertical portion and wherein the vertical portion extends substantially in the vertical direction when the base portion resides on the roof. It is also preferred that the bottom opening of the boot be adapted to accept a pipe to be covered. The pipe boot may also be open to allow installation on existing pipes. In the preferred embodiment, the top end of the vertical portion has a slit, the slit running vertically down a predetermined distance of the vertical portion of the boot and wherein the slit allows the top opening of the vertical portion to be adjusted in size to fit around the pipe to be covered.

Abstract: A flanged coupling ring for a duct element has a mounting section configured to be mounted or a connection portion of the duct element, and flange means extending outwards from the mounting section. The flange means has, along its periphery, flanged coupling portions for connecting two duct elements, each of which is provided with a coupling ring, by means of external coupling means configured to engage with the flanged coupling portions.

Abstract: A two-part clamp-connected chimney flue tee. The tee includes an elongated main section which is detachably connected to a transversely extending bull, or snout section. The main section has flue pipe connection ends and an oval cut-out portion in its sidewall, generally midway between the connection ends. The periphery of the cut-out includes an outwardly flaring flange, for mating with a corresponding contoured end of the bull section. Hooks are mounted on the inner sidewall of the main section, on opposing sides of the cut-out. Lever-actuated clamps, having a U-shaped locking member, are mounted on opposing inner portions of the sidewalls of the contoured end of the bull section. In mating the two sections, the bull section is press-fitted over the flange surrounding the cut-out. A locking member on one side of the contoured end is engaged with a respective hook. Then, the lever on the clamp is snapped toward the adjacent sidewall, into a locked position.

Abstract: A method and apparatus secure together a pair of opposing angle plates which are each mounted on one of an opposing pair of flange connectors that are each attached to the end of a different one of the opposing ends of a pair of sheet metal ducts. The apparatus includes a pair of interfitting members that include a cam surface to interlock the members to compress together the opposing pair of flange connectors.

Abstract: A device for joining two tubular elements composed of two complementary parts extending end portions of the tubular elements, the two complementary parts each including an essentially rigid substantially conical flared part extended by a semitoric flange, with the semitoric collars being capable of interlocking together.

Abstract: A flange connection for pipes has a plug connection member having a pipe section and a flange connected to one end of the pipe section, wherein the pipe section has a mounting seat and a sealing seat. The plug connection member also has a first sealing ring seated in an initial position in the mounting seat, wherein the first sealing ring rolls from the mounting seat into the sealing seat and into a sealing position when the pipe section is inserted into a pipe end.

Abstract: The invention relates to an improved system for connecting the ends of sheet metal ducts wherein each duct end is provided with an integral frame. Corner connectors defining perpendicularly extending arms are associated with each frame, and bolts or other fasteners are utilized for connecting the connectors and integral frames. The sections include an upturned portion extending perpendicularly outwardly from the duct wall, a second portion bent rearwardly from the outer end of the first portion, a third portion extending from the outer end of the second portion and forming an L-shaped double wall portion. When the frame is formed in this fashion, it is adapted to receive the side edges of respected arms of corner connectors whereby the ducts may be efficiently assembled by locating corner connectors in place and thereafter applying the fasteners used for maintaining the assembly.

Abstract: While a material pipe and a roller are revolved relative to each other with a predetermined radius, the material pipe and the roller are moved relative to each other in the direction of progress of forming by eccentrically moving the center axis of the material pipe and the revolution axis of the roller relative to each other and simultaneously moving the material pipe and the roller relative to each other in the directions of the axis. During movement in the direction of progress of the forming, an end portion of the material pipe is deflected by controlling the axis-direction moving portion so that the roller is moved relative to the material pipe in the direction of the axis when the circumferential position of the roller, with respect to a circumference of the material pipe, changes from an inner side of the direction of deflection toward an outer side of the direction of deflection.

Abstract: A unitary annular reduction duct suitable for joining pipes comprising an annular entrance collar of a given diameter, a corrugated and gradually inwardly tapered reduction portion that is contiguous with the collar section and a corrugated and substantially vertical annular exit portion contiguous with the reduction portion whereby the reduction portion has a diameter less than the collar section. The reduction duct may also be used to join pipes of different shapes.

Abstract: A cylindrical workpiece (20) is mounted onto and connected to a mandrel (14) that is itself mounted for rotation about a vertical axis (12). A first end portion of the workpiece (20) is housed within the mandrel (14). A second end portion-projects axially outwardly beyond a radial forming surface (60) on the mandrel (14). A first forming roller (30) is mounted on a swing post (52) that is positioned by an adjustable length strut (56). The strut (56) is elongated to swing the post (52) downwardly and place the roller (30) inside the second end portion of-the workpiece (20). Then, a lead screw (28) is used for pulling on a base (50) that supports the post (52). This pulls a convex face portion (32) of the roller (30) against the inside of the second end portion of the workpiece (20). Lead screw operation moves the roller (30), causing it to stretch the second end portion of the workpiece (20) and move it up onto and then move it radially outwardly along the forming surface (60).

Abstract: A fabricated connector for oval shaped cross section ducts is provided. The fabricated connector has two oval shaped connector elements, each of which are formed from two semi-circular rings to which universal connectors are permanently affixed on each end of the semi-circular rings by the manufacturer. The semi-circular rings with universal connectors attached are then shipped to the field where angle pieces are inserted and fixed between the universal connectors of the two semi-circular rings to form the precise shape of oval connector desired.

Abstract: Apparatus and method for dispensing L-shaped duct connectors. The apparatus supports a stack of nested L-shaped connectors and includes a separator for causing the second bottommost connector to be biased out of nesting engagement with the first bottommost connector in the stack upon the application of an advancement force to the first bottommost connector. The apparatus includes an advancement assembly for selectively advancing the first bottommost connector to an installation position wherein it may be installed in a C-shaped flange attached to a duct segment. After the first bottommost connector is moved to the installation position, the second bottommost connector then moves under the influence of gravity to a position wherein it can be advanced to the installation position.

Abstract: An exhaust elbow (1) is provided with a single exhaust outlet (2) with an outlet mounting flange (3) and at least two exhaust inlets (4, 5, 6) with an inlet mounting flange (7) for fastening on the engine block of a motor vehicle. The exhaust guiding of the exhaust elbow (1) between the inlet mounting flange (7) and the outlet mounting flange (3) is formed by a single-walled sheet metal hood (8) forming a collection line. The sheet metal hood (8) surrounds all exhaust inlets (4, 5, 6) together, without individual pipes being formed. Such a simple sheet metal elbow can be manufactured at a low cost and with low weight and nevertheless has sufficient ability to function, is dimensionally stable and can be used in a versatile manner.

Abstract: A duct assembly made from multiple duct sections for transporting pressurized fluid therethrough which can be formed simply by laborers at a building site or elsewhere and has a strong joint resistant to leakage. The joint rigidizes each duct section and the duct assembly, permitting duct assemblies including a greater number of joined duct sections to be put together and lifted into place The joint is formed by passing fasteners through a corner flange connection member associated with one duct section, through integral flanges of the one duct section and other duct section arranged in end-to-end relation with the one duct section, and through a corner flange connection member associated with the other duct section. The act of installing the fastener tightly pulls together the integral flanges and makes and integral connection between them.

Abstract: A cylindrical workpiece (20) is mounted onto and connected to a mandrel (14) that is itself mounted for rotation about a vertical axis (12). A first end portion of the workpiece (20) is housed within the mandrel (14). A second end portion projects axially outwardly beyond a radial forming surface (60) on the mandrel (14). A first forming roller (30) is mounted on a swing post (52) that is positioned by an adjustable length strut (56). The strut (56) is elongated to swing the post (52) downwardly and place the roller (30) inside the second end portion of the workpiece (20). Then, a lead screw (28) is used for pulling on a base (50) that supports the post (52). This pulls a convex face portion (32) of the roller (30) against the inside of the second end portion of the workpiece (20). Lead screw operation moves the roller (30), causing it to stretch the second end portion of the workpiece (20) and move it up onto and then move it radially outwardly along the forming surface (60).

Abstract: A pipe connection for use in a ventilating duct system having ducts with circular cross-section is adapted to be inserted with a close fit into an outer pipe and be connected therewith. The pipe connection has a circumferential groove, in which a circumferential seal sealing against the inside of the outer pipe is arranged. A terminal edge portion of the pipe connection comprises an outer conical portion which has a diameter decreasing towards the end of the pipe connection, and a circumferential guide surface having such a diameter that said close fit is obtained. The axial length (L3) of the terminal edge portion constitutes about 1.5-5.5% of the diameter of the guide surface. The outer conical portion at its end has a diameter which constitutes about 97-99.9% of the diameter of the guide surface.

Abstract: A method and apparatus shapes and dimensions the flanges of angle plates to ensure that the plates can be stacked without nesting.

Abstract: A fan duct assembly includes a fan duct (200), a panel (600), and a locking plate (700). One end of the fan duct defines a rectangular opening (204) with a peripheral flange (220). A pair of ribs (224) is formed on one side of the flange. A pair of L-shaped catches (602) is stamped from the panel. The catches abut against the ribs, to retain the side of the flange. The locking plate is attached to the panel opposite to the catches. The locking plate includes a base (710) and a vertical portion (720) extending from the base. An L-shaped resilient tab (730) is inclinedly stamped from the locking plate, to resiliently abut against the side of the fan duct and the flange. A pair of resilient feet (716) extends from opposite sides of the base, each foot having a free end portion resiliently abutting against the flange.

Abstract: The invention relates to an improved system for connecting the ends of sheet metal ducts wherein each duct end is provided with a double walled frame. Corner connectors defining perpendicularly extending arms are associated with each frame, and bolts or other fasteners are utilized for connecting the connectors and frames. The respective double walled frames comprise integral sections at the duct ends. The sections include an upturned portion extending perpendicularly outwardly from the duct wall, a second portion bent rearwardly from the outer end of the first portion, a third return portion, and an inner wall portion extending from the outer end of the third portion and forming a L-shaped portion. When the frame is formed in this fashion, it is adapted to receive the side edges of respective arms of corner connectors whereby the ducts may be efficiently assembled by locating corner connectors in place and thereafter applying the fasteners used for maintaining the assembly.

Abstract: Methods and devices for joining two or more panels together are provided. The methods allow joining of panels of material such as glass fiber board, and are particularly useful for forming ducts or tubes. Fasteners provided have two planar members, joined together, and the planar members have protrusions that are integral to the planar members and are intended to at least partially protrude the panels joined by the devices.

Abstract: A cylindrical workpiece (20) is mounted onto and connected to a mandrel (14) that is itself mounted for rotation about a vertical axis (12). A first end portion of the workpiece (20) is housed within the mandrel (14). A second end portion projects axially outwardly beyond a radial forming surface (60) on the mandrel (14). A first forming roller (30) is mounted on a swing post (52) that is positioned by an adjustable length strut (56). The strut (56) is elongated to swing the post (52) downwardly and place the roller (30) inside the second end portion of the workpiece (20). Then, a lead screw (28) is used for pulling on a base (50) that supports the post (52). This pulls a convex face portion (32) of the roller (30) against the inside of the second end portion of the workpiece (20). Lead screw operation moves the roller (30), causing it to stretch the second end portion of the workpiece (20) and move it up onto and then move it radially outwardly along the forming surface (60).

Abstract: A flange structure formed from a plurality of joined flange segments is provided. The joined flange segments form a generally circular opening for a conduit. The flange structure can be connected to a substrate by fasteners extending through two oval shaped openings connecting the two forces. At least one shim is attached to the flange segments through narrow bridge connections which can be fractured by hand or with a hand held tool.

Abstract: A collar for connecting a duct to a wall having a hole therein bounded by an edge having a predetermined thickness. The collar is constructed from a sheet of material having top, bottom, left and right edges, the sheet forming a tubular structure in which the left and right edges overlap. The sheet includes a groove for engaging the edge of the hole. The sheet also includes first and second detents spaced apart thereon. The overlap of the left and right edges at the top edge changes when the spacing between the first and second detents is changed. The collar also includes a first fastener for fixing the overlap of the left and right edges at the top edge when the edge of the hole is engaged in the groove and a second fastener for fixing the overlap of the left and right edges at the bottom edge. In the preferred embodiment of the present invention, the groove includes a layer of a sealing material for forming a seal between the sheet of material and the edge of the hole.

Abstract: An insulated air duct apparatus including insulated duct modules and associated insulated fitting apparatus for transferring a volume of fluid in a warm air heating and air conditioning installation without employing external insulation or structural support members, otherwise required to support and insulate duct apparatus including a plurality of lightweight duct modules in combination with take-off connectors for joining such modules, each duct module comprising duct walls joined by corner members wherein said duct walls and take-off connectors comprise rigid fibrous glass (RFGB) with reinforced facing having inherent structural strength such that each duct module is self supporting.

Abstract: A device and system for securing adjacent segments of duct work formed from fibrous glass duct board insulation and the like is disclosed. The device comprises a corner member having two legs disposed at approximately right angles, each of said legs having oppositely facing and substantially parallel adjacent channels disposed therein to accommodate portions of opposed edges of adjacent segments of duct work. The system includes a plurality of corner members each having two legs disposed at approximately right angles, said legs having substantially parallel and oppositely facing adjacent channels disposed therein to accommodate at least a portion of the opposed edges of adjacent segments of duct work.

Abstract: A quick connector of the ball-lock type includes a socket member, a plug member and a slidable sleeve which are specifically designed to permit manufacture by deep drawing of a sheet metal. The socket member and the plug member are each shaped in the form of a stepped tube and the plug member is inserted into the socket member in a telescoping fashion to form an annular chamber therebetween. An O-ring and a backup ring are mounted within the annular chamber by inserting them into the bore of the socket member.

Abstract: Internal connectors are configured to conformingly fit within each of the mating ends of adjacent duct elements. The internal connectors each comprise a sleeve having an outwardly extended wall disposed about a perimeter of the internal connector. The mating ends each have a stepped face configured to conformingly mate with the internal connector. To connect the duct elements together, the mating ends are mated to each side of the internal connector and the mating ends are glued to each other. Because the mating ends and the internal connectors conformingly mate with each other, the duct elements will be aligned with each other. The internal connectors are glued to a side wall of the duct element wherever branch take-offs are made.

Abstract: A pipe lap joint is disclosed with an improved sealing zone structure in the overlap region of the pipes. The sealing zone comprises a slot extending from the end of the outer pipe to an inner end wall of the slot. The joint comprises a band clamp with a clamping band which covers the sealing zone including the inner end of the slot. The slot has a bridge extending between the sidewalls and dividing the slot into an outboard slot segment and an inboard slot segment. The bridge has an axial dimension which is substantially smaller than the axial length of either of the slot segments. When the band clamp is tightened, the sealing zone is collapsed by collapse of the slot and consequent deformation of the bridge such that it obstructs fluid flow between the slot segments.

Abstract: A lap joint includes an outer, flexible, cylindrical tube; an inner, solid, cylindrical pipe; and a securing device for compressing the flexible tube around the pipe for securing the flexible tube to the pipe and for providing a substantially leak-free connection between the flexible tube and the pipe. The flexible tube has first and second ends and a first diameter. The flexible tube includes a plurality of captured slots punched through the flexible tube at least at the first end. The plurality of captured slots have a first plurality of metal deformations to prevent circumferential slippage of the flexible tube and are disposed annularly around the flexible tube. Each of the plurality of captured slots are inboard of the first end and do not extend to the first end. The securing device is arranged and configured to completely cover the plurality of captured slots. The flexible tube also includes a plurality of relief slots punched through the flexible tube at least at the first end.

Abstract: The invention relates to a butt joint between two circular or flat, oval air duct sections (10) each with a connection flange (32) at each end and a ring (34) clamping the connection flanges together. Said connection flanges (34) are moulded, to form one part, to the duct wall (12) of each air duct section (10) and each have an outwardly-projecting annular edge (14) and clamping legs (24) drawn together by corresponding side legs (38) of the clamping ring (34). Each annular edge (14) forms an angle of 80.degree. to 90.degree., preferably 87.degree. to 89.degree., with the associated duct wall (12). Each connection flange (32) can also have another or a plurality of supporting legs (28).

Abstract: A pipe lap joint is disclosed with an improved sealing zone structure in the overlap region of the pipes. The sealing zone comprises a serpentine slot extending from the end of the outer pipe to an inner end-wall of the slot. The joint comprises a band clamp with a clamping band which covers the sealing zone including the inner end of the slot. One sidewall of the slot defines an inwardly protruding tooth and the other sidewall defines another inwardly protruding tooth with a narrow passage between the teeth which is provided by rounded corners on the teeth. The slot also includes a bulbous end-wall which facilitates uniform collapse of the sealing zone. When the band clamp is tightened, the sealing zone is collapsed such that the two teeth engage each other and seal the serpentine slot against leakage.

Abstract: A coaxial pipe assembly for a direct vent fireplace coaxial flue-system. The coaxial pipe assembly has an inner flue pipe residing within an outer flue pipe where the two pipes are retained to one another. Each flue pipe has a male connector and a female connector with the male connector of the outer flue pipe being aligned with the female end of the inner flue pipe. Lances are formed into the female connector of the outer flue pipe and a locking ridge is formed into the male connector of the outer flue pipe. Each of the two flue pipes of a first coaxial pipe assembly is designed to engage their counterpart in an adjacent coaxial pipe assembly. This engagement seals the adjacent inner flue pipes and is fixed upon the locking ridge passing the lances of a first coaxial pipe assembly to snap into place.

Abstract: A device for coupling together pipes, which at their end have an outwardly directed bead, comprises an annular clamping strap (1) and a clamping mechanism (4-6) arranged at the ends (2a, 2b) of the clamping strap. Between the ends (2a, 2b) of the clamping strap (1), a sealing element (7) is arranged for sealing the joint between the ends (2a, 2b).

Abstract: An end plug for a stab-type coupler for a plastic pipe, the coupler having a first shell with a passageway therethrough. The end plug includes a hollow, cylindrical portion having a first end and a second end. An end wall is sealably attached to the cylindrical portion first end. External threads are formed on the cylindrical portion at the first end wherein the external threads engage internal threads on an end of the first shell. At least one vent hole is provided in the cylindrical portion of the end plug between the internal threads and the second end with the vent hole allowing fluid to vent when the external threads are partially unthreaded from the internal threads on the shell.

Abstract: The present invention discloses a coupling for use in vent systems which is self-sealing. The coupling includes a gasket in a female part of the coupling that seals against an end of a male part. The female part also including a mechanical locking device that clamps onto a recess in the male part to prevent disconnection. The coupling prevents puddling of corrosive fluids in the coupling at points of metal-to-metal contact and, hence, prevents premature corrosion.

Abstract: In the case of the pipe connection of two overlapping pipes a flexible ring is arranged between the interior pipe and the exterior pipe and, before the bracing, is axially displaceable on the interior pipe. The flexible ring and the exterior pipe have a spherical interacting outer and inner contour which ensures the angular mobility. The fixing of the pipe connection after the adjustment takes place by two tensioning bows which are fixedly mounted on the exterior pipe. This permits a particularly easy handling during the adjustment and the fixing of the pipe connection.

Abstract: A sheet-metal elbow is coupled by direct attachment to a flat sheet-metal air inlet panel of an air distribution boot or register box by roll-formed flange portions that are mated in interlocking, overlapping engagement with each other. The air inlet panel includes an outwardly flared coupling flange bordering an air inlet opening. The neck of the sheet-metal elbow includes a folded coupling flange that is dimensioned for interfitting, overlapping engagement with the outwardly flared elbow coupling flange. The coupling flanges are clasped together by a hydraulic ram that drives an expandable mandrel into a V-shaped die cavity. The tightly clasped, overlapping flange portions permit smooth, continuous rotation of the elbow through 360.degree. with respect to the register box for alignment with a branch conduit. The interlocked flanges also provide a strong mechanical union that is virtually leak-free under normal ventilation air flow conditions.