Abstract:
A conduit coupling (20) is comprised of a male conduit (22), a mating female member (24), means for sealing (26) and a fastener (28) to couple the male conduit (22) to the female member (24). The male conduit (22) has a first and second expanded diametral portions (46 and 50) separated by a nominal diametral portion (48). The sealing means (26) externally surrounds the nominal diametral portion (48) and prevents fluid from passing between an exterior surface (40) of the male conduit (22) and an adjacent inside surface (74) of the female member (24). Thus, the total longitudinal length of the conduit coupling (20) is less than most threaded couplings.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to a conduit coupling through which fluid flows and specifically to a male conduit having expanded diametral portions thereof for insertion within a female member. 
     In the automotive industry, as well as for many other industries, the need always exists for low cost, reliable and easy to assembly components. This need is especially apparent with respect to providing a connection between fluid conveying conduits such as fuel, brake or refrigerant lines. Traditionally, such a connection is comprised of a male tubular member being retained within a female housing by a threaded fitting, bolted-on flanged brackets or flare fittings. 
     More recently, snap together quick connect attachments have been used in place of the aforementioned conventional devices. In order to retain such a quick connect fastener, many tubular members have a bead circumferentially located therearound. This bead may be integrally formed or mechanically attached onto the outside surface of the male conduit. Furthermore, it is important that this bead be firmly attached to a predetermined longitudinal position on the male conduit in order to maintain a secure and leak resistant fit within the mating female housing or connector half. If such a connection were to become dislodged or leak, the vehicle could become disabled. While quick connect fasteners are significant improvements within the art, the male conduits used in combination therewith have not adequately provided a low cost and secure sealing seat integral with the male conduit. Furthermore, conventional couplings allow the male conduit to axially move in relation to the adjacent female housing. Therefore, it would be desirable to have a conduit coupling which provides a low cost, longitudinally secure and integral sealing seat on a male conduit which also promotes axial alignment with the mating female housing thereby avoiding the aforementioned problems. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, the preferred embodiment of a conduit coupling is comprised of a male conduit, a mating female member, means for sealing and a fastener to couple the male conduit to the female member. The male member has a first and second expanded diametral portions separated by a nominal diametral portion. The sealing means externally surrounds the nominal diametral portion and prevents fluid from passing between an exterior surface of the male conduit and an adjacent inside surface of the female member. In another aspect of the present invention, a quick connect fastener couples the male conduit within the female member. 
     The conduit coupling of the present invention is advantageous over conventional couplings in that a sealing seat is integrally formed within a male conduit. Thus, a low cost and longitudinally accurate sealing retention area is created. Furthermore, the present invention conduit coupling is also advantageous since a first and second expanded diametral portions on the male conduit also serve as axial alignment bearing surfaces against an inside surface of a female member. An additional benefit is that the conduit coupling of the present invention is longitudinally compact as compared to many traditional attachment systems. Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a sectional view showing a first preferred embodiment of a conduit coupling of the present invention; 
     FIG. 2 is a sectional view showing a second preferred embodiment of a conduit coupling of the present invention; 
     FIG. 3 is an exploded perspective view of a first alternate embodiment of the present invention conduit coupling of FIG. 2; 
     FIG. 4 is a sectional view, taken along line 4--4 of FIG. 3, of the first alternate embodiment of the present invention conduit coupling; 
     FIG. 5 is a sectional view showing a second alternate embodiment of a male conduit and means for sealing of the present invention conduit coupling of FIG. 2; 
     FIG. 6 is an end elevational view showing a first preferred embodiment of a quick connect fastener used in the present invention conduit coupling of FIGS. 1 and 2; and 
     FIG. 7 is an end elevational view showing a second preferred embodiment of a quick connect fastener used in the present invention conduit coupling of FIGS. 3 and 4. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A conduit coupling can be used to join a pair of mating tubular members or conduits to one another. For example, a pair of brake, coolant, pneumatic or other flexible hoses may be attached to one another within an automotive vehicle. A conduit coupling can also be used to join a conduit to a fluid carrying structure. For example, a flexible or rigid conduit may be coupled to an engine block, radiator or exhaust pipe. 
     Referring to FIG. 1, a first preferred embodiment of a swivelable conduit coupling 20 is comprised of a male conduit 22, a female member 24, a seal 26 and a quick connect fastener 28. Male conduit 22 is a somewhat rigid metallic member which is securely affixed within the end of a flexible hose (not shown). Male conduit 22 has an exterior surface 40 and an interior surface 42 joined by a distal edge 44. Male conduit 22 also has a first expanded diametral portion 46, a nominal diametral portion 48 and a second expanded diametral portion 50. Each diametral portion 46, 48 and 50 has a substantially cylindrical cross sectional shape thereto. Furthermore, expanded diametral portions 46 and 50 each have substantially the same diameter while the diameter of nominal diametral portion 48 is relatively smaller. Thus, a sealing seat is defined within this radially grooved area. 
     Female member 24 has a female conduit 60, a receptacle 62, a flange 64 and a collar 66. Female conduit 60 has an inner surface 68 of substantially cylindrical cross sectional shape defining a passageway 70 therethrough. Receptacle 62 is joined to female conduit 60 by a radially projecting ledge 72. Receptacle 62 has an inside surface 74 which defines a substantially cylindrical bore therethrough. Flange 64 has a frusto-conical cross sectional shape with a constricted portion 76 connected to receptacle 62. Flange 64 also has a distal edge 78 which is opposite from constricted portion 76. Collar 66 has a substantially cylindrical body 90 which snugly surrounds a portion of receptacle 62 and flange 64. An arm 92 is inwardly turned from body 90 of collar 66 so as to create a shoulder 94. Collar 66 further has a lead-in portion 96 which defines an open end of female member 24. An inwardly projecting tab or other means may also be incorporated within collar 66 to prevent longitudinal misplacement along receptacle 62. 
     Seal 26 is preferably an elastomeric O-ring which is preassembled to male conduit 22 within the sealing seat defined by portions 46, 48 and 50 of male conduit 22. However, seal 26 could alternatively consist of a closed cell sponge-like material, a pumpable sealant, a thumb grade sealant, or other sealing means known to one skilled in the art. 
     As can best be observed in FIGS. 1 and 6, quick connect fastener 28 is a flat washer-like device having a pair of central jaws 120, also known as a central attachment section, and a pair of outer jaws 122, also known as an outer attachment section. Central jaws 120 and outer jaws 122 are connected to each other through a neck section 124. Furthermore, central jaws 120 define a substantially semi-circular shape therebetween which is compressibly affixed around exterior surface 40 of male conduit 22 longitudinally adjacent to second expanded diametral portion 50 thereof opposite from distal edge 44. Outer jaws 122 create a substantially circular shape substantially concentric with central jaws 120. However, a gap 126 is located between a distal end 128 of each outer jaw 122. Moreover, a peripheral edge 130 of outer jaws 122 is inwardly compressed by lead-in portion 96 and inwardly turned arm 92 of collar 66 when quick connect fastener 28 is longitudinally inserted within female member 24. Insertion may be further enhanced through use of a tool (not shown) which can be inserted within openings 132 in outer jaws 122. When fully inserted, outer jaws 122 are outwardly urged such that a face 134 thereof abuts against shoulder 94 of collar 66. Quick connect fastener 28 is made from a sheet of strip stock steel. 
     When male conduit 22 is fully inserted within receptacle 62, expanded diametral portions 46 and 50 provide bearing surfaces which inhibit axial misalignment in relation to female member 24. Furthermore, the sealing seat created between portions 46, 48 and 50 of male conduit 22 accurately control the radial compression and longitudinal location of seal 26. 
     A second preferred embodiment of a quick connect fastener 28 is shown in FIG. 7. This fastener 28 is formed from a semi-flexible wire and has a pair of central jaws 150, also known as a central attachment section, and a pair of outer jaws 152, also known as an outer attachment section. Central jaws 150 and outer jaws 152 are connected to each other through elbow sections 154. Central jaws 150 compressibly engage male conduit 22 (see FIG. 1) and outer jaws 152 engage collar 66 (see FIG. 1) of female member 24 (see FIG. 1). 
     A second preferred embodiment of conduit coupling 20 of the present invention is shown in FIG. 2. A female member 170 has a female conduit 172 and a female receptacle 174. Female receptacle 174 is defined by a first inside surface 176 and a longitudinally adjacent second inside surface 178. First inside surface 176 has a relatively smaller substantially cylindrical cross sectional diameter as compared to second inside surface 178 which also has a substantially cylindrical cross sectional shape. Receptacle 174 further has a chamfered surface 180, a grooved undercut 182, an intermediate surface 184 and a tapered lead-in surface 186. Tapered lead-in surface 186 is proximate with an open end 188 of female member 170. In this embodiment, a male conduit 190 is substantially similar to that of the first preferred embodiment, however, a first expanded diametral portion 192 has a diameter congruent with first inside surface 176 of female member 170. Also, a second expanded diametral portion 194 of male conduit 190 has a diameter congruent with second inside surface 178 of female member 170. Accordingly, the diameter of second expanded diametral portion 194 is greater than that of first expanded diametral portion 192. Nevertheless, a nominal diametral portion 196 acts in concert with the adjacent expanded diametral portions 192 and 194 to provide a sealing seat for a seal 198. A quick connect fastener 200 is used to couple male conduit 190 to undercut 182 of female member 170. 
     In FIGS. 3 and 4 an alternate embodiment of the present invention conduit coupling 20 is shown. In this embodiment, a male conduit 240 is identical to that of the first preferred embodiment. Furthermore, a female member 242 is similar to that disclosed in the second preferred embodiment except that a receptacle 244 has a substantially uniform inside surface 246. This exemplary embodiment illustrates the use of a first auxiliary attachment ring 250 and a second auxiliary attachment ring 252 in combination with a quick connect fastener 254. Quick connect fastener 254 is similar in design to that shown in FIG. 7. 
     Both auxiliary attachment rings 250 and 252 are annular in shape and have an inner attachment section 256 which compressibly engages around an exterior surface 258 of male conduit 240. Auxiliary attachment rings 250 and 252 further have an outer attachment section 260 which snugly rides against a pair of intermediate cylindrical surfaces 262 longitudinally bordering an undercut groove 264 within female member 242. Quick connect fastener 254 is longitudinally trapped between the pair of auxiliary attachment rings 250 and 252. This construction allows quick connect fastener 254 to be made from a more radially resilient and less longitudinally rigid material as compared to the prior embodiments. This is accomplished by allowing the pair of auxiliary attachment rings 250 and 252 to longitudinally support quick connect fastener 254. Furthermore, four arcuate slots 266 are located between inner and outer attachment sections 256 and 260, respectively, of auxiliary attachment rings 250 and 252 such that installation or disassembly tools can be inserted within spaces 268 of quick connect fastener 254. An annular bushing 270 can optionally surround exterior surface 258 of male conduit 240 proximate with second auxiliary attachment ring 252. This bushing 270 aids in ensuring the desired longitudinal location of quick connect fastener 254 during insertion thereof within female member 242. An O-ring seal 272 surrounds a nominal diametral portion 274 of male conduit 240. 
     Referring to FIG. 5, a nominal diametral portion 290 of a male conduit 292 is longitudinally lengthened so as to provide a sealing seat for a pair of O-ring type seals 294 and 296 with a washer 298 longitudinally located therebetween. Of course, one skilled in the art would appreciate that various alternating patterns of expanded diametral portions and nominal diametral portions can be longitudinally positioned along a male conduit without deviating from the present invention. 
     While various embodiments of this conduit coupling have been disclosed, it will be appreciated that various modifications may be made without departing from the present invention. For example, the quick connector can be of a type disclosed within the parent application. Furthermore, a non-quick connect fastener such as a bolted-on flange or threaded fitting fastener can be used to join a male conduit to a female member. Various materials have been disclosed in an exemplary fashion, however, a variety of other materials may of course be employed. It is intended by the following claims to cover these and any other departures from the disclosed embodiments which fall within the true spirit of this invention.