BACKG ROUND OF THE I NVENTION

[0001] The present invention relates to a push-to-connect plumbing fitting.

[0002] There have been numerous proposa ls for push-to-connect plumbing fittings which eliminate the need for additional labor steps in providing a connection of a fluid conduit to the fitting. With push-to-connect fittings, typically no soldering is necessary nor is crimping req uired to complete the seal between the fitting and a fluid conduit. One proposa l for such a fitting is disclosed in U.S. Publication 2010/0171302 published on July 8, 2010. Push-to-connect fittings may require a separate tool for the removal of a fluid conduit from the fitting once assem bled. Some fittings integrally includes a release ring for such purpose. Nearly a ll of the push-to-connect fittings employ a grab ring made of a metal, such as stainless steel, with tines that extend inwardly and engage and hold a fluid conduit inserted into the fitting. Also, the fittings typically include at least one O- ring providing a fluid-tight seal for the connection.

[0003] Unfortu nately, most of the push-to-connect fittings are relatively com plicated to manufacture and require expensive tooled parts and/or forming processes to complete. As a result, they can become fairly expensive in an environment where competition is relatively vigorous.

SUM MARY OF TH E INVENTION

[0004] A plum bing fitting made of a material that allows it to be formed includes a housing defining a socket with an interna l ann ular shoulder for sealably receiving a cartridge. A two-piece cylindrical ca rtridge has semi-cylindrical interlocking halves that lockably engage a grab ring positioned between the interlocking halves of the cartridge. The grab ring has inwardly projecting a nnula rly spaced tines for gripping and holding a fluid conduit inserted into the housing a nd cartridge past the grab ring. The cartridge includes a ring seal positioned against the annular shoulder and i nternal wal l of the socket for sea lably coupling the cartridge to the socket and sealably coupling a fluid conduit to the cartridge. I n a one embodiment, the ca rtridge is held within the housing socket by a crim ped-over end. I n a preferred embodiment, a n integra l release ring is also coupled to the cartridge, such that a separate tool is unnecessary to disconnect a fluid conduit from the fitting.

[0005] These and other features, objects and advantages of the present invention will become apparent upon reading the following description thereof together with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Fig. 1 is a perspective view of a cartridge embodying the push-to-connect structure;

[0007] Fig. 2 is a cross-sectional view of a plumbing fitting showing the connection of fluid conduits at opposite ends of a coupling using two cartridges of Fig. 1 at opposite ends;

[0008] Fig. 3 is an enlarged exploded side elevational view of the components of the cartridge shown in Fig. 1;

[0009] Fig. 4 is an exploded perspective view of the components of the cartridge shown in Figs. 1 and 3; and

[0010] Fig. 5 is an enlarged perspective view of the grab ring shown in Figs. 1-4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0011] Referring initially to Fig. 1, there is shown a push-to-connect cartridge 20 for use with a plumbing fitting 10, such as seen in the example of Fig. 2, for coupling a pair of conduits 12 and 14 to each other using the push-to-connect fitting 10. Fitting 10 can be any type of plumbing fitting, such as an elbow, a T, a valve, a reducing fitting, an adapter, or the like. The cartridge 20 can be used with any of these fittings. The cartridge 20, such as shown in Fig. 1, is used at each of the ends of the fitting 10 (shown as 20 and 20 ^' in Fig. 2) with the fitting 10 comprising an in-line coupling having a body 11 with a pair of sockets 13 and 15 at opposite ends. Each socket has an annular shoulder 16 for engagement by a ring seal 80 of the cartridges 20, 20 ^' , as also seen in Figs. 1, 3, and 4. Once the cartridges 20, 20 ^' have been inserted into the sockets 13, 15, the ends 18 of the fitting 10 are crimped over to complete the installation of the cartridges 20, 20 ^' into the fitting 10. Fitting 10 is typically made of a ductile material, such as a copper alloy, which allows ends 18 to be roll-formed, crimped, or otherwise deformed to hold the cartridges 20, 20 ^' in sealed engagement within the plumbing fitting 10. Conduits 12 and 14 can then be inserted into the fitting 10 with ends engaging a dimple-like stop 19 to assure the full, locked insertion and sealing of the fluid conduits 12 and 14 in the fitting 10.

[0012] Cartridge 20 comprises, as best seen in Figs. 3 and 4, a clam shell design including a first semi-cylindrical ca rtridge half 30 and a second mating semi-cylindrical cartridge half 40. Each cartridge half includes a centered semi-annular groove 32 and 42, respectively, for receiving and holding grab ring 60 when assembled. Communicating with the annular grooves 32 and 42 are radially extending annularly spaced slots 34, 44, respectively, which receive spaced-apa rt tabs 64 extending outwardly on grab ring 60 to further assist in captively holding the grab ring 60 within the cartridge 20 (Fig. 1) when cartridge halves 30 and 40 a re assembled. Cartridge halves 30 and 40 further include interlocking tabs 36 and slots 46, respectively, which mate to interlock the cartridges halves when assembled, as best seen in Fig. 1. The cartridge halves 30 and 40 each a lso include a beveled surface 31 and 41 (Fig. 4), which conforms to the angle of downwardly and inwardly projecting tines 62 of grab ring 60 in spaced relationship thereto, as best seen in Fig. 2, to allow the tabs 72 of a release ring 70 to deflect the tines 62 of grab ring 60 outwardly and away from conduits 12 and 14 when a release ring 70 is pushed inwardly toward the center of fitting 10.

[0013] Cartridge halves 30 and 40 further include a n annular shoulder 38 and 48 (Fig. 4), respectively, which lockably engage the shoulders 78 on the resilient tapered tabs 72 of a release ring 70. The annular spaced-apa rt tabs 72 are flexible by virtue of the annularly spaced slots 74 formed in the cylindrical body 75 of ring 70. This allows the tabs to deflect inwardly during the assembly of release ring 70 to the cartridge 20. Cartridge halves 30 and 40 also include downwardly projecting tabs 39 and 49, respectively, which engage blind apertures 89 in a washer-shaped ring seal 80 to hold the seal to the cartridge 20, as seen in Fig. 1.

[0014] Cartridge 20 is assembled in a clam shell type design with semi-cylindrical cartridge halves 30 and 40 inserted around the grab ring 60 with the tabs 64 of ring 60 extending radially outwardly through slots 34 and 44 in the cartridge halves 30 and 40, respectively. The ring-like body 66 of grab ring 60 extends into grooves 32, 42 with the tabs 64 extending through radially extending slots 34 and 44. The mating interlocking tabs 36 and slots 46 of cartridge halves 30, 40, respectively, complete the assembly of the cartridge 20 to the grab ring 60. Ring seal 80 can then be inserted onto the tabs 39 and 49 of the cartridge 20 and the release ring 70 inserted through the open top end of the cartridge (as seen in Fig. 1). The annular shoulder 76 of release ring 70 extends over the annular upper surface 26 of cartridge 20 in spaced relationship thereto, as shown in Fig. 1. This positions the tapered tabs 72 of the release ring 70 in spaced relationship to the tines 62 of the grab ring 60 and sufficient space between the lower surface of shoulder 76 and the upper annular surface 26 of cartridge 20 to allow the release ring 70 to be pushed inwardly toward the center of fitting 10 to deflect tines 62 outwardly, releasing their grip on the conduit 12 or 14 if it is desired to remove a fluid conduit from the push- to-connect coupling.

[0015] Cartridge halves 30 a nd 40 are integrally molded of suitable polymeric material, such as polyoxymethylene (POM), polyphenylsulfone (PPSU), or the like, as is the release ring 70. The grab ring 60 is typically made of a noncorrosive spring steel material, such as stainless steel. The elastomeric relatively flat ring seal 80 is made of a suitable elastomeric material and includes an annular inwardly extending groove 82 allowing its compression against shoulder 16 of the plumbing fitting socket 13 or 15, as illustrated in Fig. 2, with its outer surface 84 engaging inner cylindrical surfaces of sockets 13 and 15. This seals the cartridge 20 to the fitting 10 while the inner edges 86 of seal 80 engage the outer cylindrical surface of conduits 12 or 14 to seal the connection between these fluid conduits and the fitting 10. Thus, the ring seal 80 seals both the cartridge 20 to the fitting 10 and the conduits 12, 14 to the ca rtridge 20.

[0016] It will become a pparent to those skilled in the art that various modifications to the preferred embodiment of the invention as described herein can be made without departing from the spirit or scope of the invention as defined by the appended claims.