Quick connection system for automotive fluid transport lines

Abstract

Quick connection (25) for a first and a second fluid line (26, 27), comprising: a receiving element (28) having a first end (28a) designed to be mounted on a tip (26a) of the first fluid line (26), a middle section designed to receive a tip (27a) of the second fluid line (27), and a second end (28b) defining a cylindrical sleeve designed to be spaced apart from the tip (27a) of the second fluid line (27); an elastic seal (32); and a snap-lock mechanism comprising: several shaped fixing half-shells (34, 35), each of which extends longitudinally from a collar section (34a, 35a) to a clip section (34b, 35b), the fixing half-shells (34, 35) being arranged cylindrically to define a socket designed to receive the cylindrical sleeve of the receiving element (28);and a tension band (36) designed to be secured over the collar sections (34a, 35a) to lock the fixing half-shells (34, 35) at the tip (27a) of the second fluid line (27) with the clip sections (34b, 35b) cantilevered over the tip (27a) of the second fluid line (27); wherein each of the clip sections (34b, 35b) includes a hook (40) designed to snap over an external offset (47) on the receiving element (28) to create a connection between the fluid lines (26, 27), compressing the elastic seal (32) between the cylindrical sleeve and the tip (27a) of the second fluid line (27).

Description

CROSS REFERENCE TO RELATED APPLICATIONSNot true.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCHNot true.BACKGROUND OF THE INVENTIONThe present invention relates generally to fluid line couplings, and more particularly to quick connect pipe couplings for automotive fluid systems such as a transmission oil cooler.Many different types of fluid handling systems may use a quick connect system wherein two fluid lines are selectively connected by a releasable coupling. Particularly in a mass production application (e.g. automotive assembly lines), a snap-fit coupling is desired that can be completed without the need for tools or other components or fasteners. The quick connect must be removable to allow replacement or maintenance of a fluid conduit or fluid handling component (which may require a tool).From DE 695 32 720 T2 and DE 10 2015 210 005 A1, a quick connection for a first and a second fluid line is known.Automotive fluid systems using a quick connect may include a transmission oil cooler, an air conditioning refrigerant circuit, a fuel delivery circuit, and others. The fluid conduits may include tubes formed from metal, rubber, or other plastics. A common location for a quick connect would be between a metal tube extending from a heat exchanger and a flexible hose for transporting fluid to / from a target device. Because the fluid system can carry volatile liquids, the quick connect system must meet stringent performance requirements, such as forming a solid, durable, and durable seal in a device that is durable, durable, resistant to impacts, and resistant to chemicals, and capable of tolerate extreme heat and cold while being easy to install and disassemble. The size must be compact to preserve space within a particular vehicle.It is important, especially during vehicle assembly operations, that complete line engagement be achieved at all times. In the automotive industry, for example, oil conduits are referred to as "inverted delta" items, requiring extremely high reliability. When two such oil transport lines are manufactured in the assembly line, it is highly desirable for the proper completion of the connection that it can be easily confirmed by the assembler. Perceptible feedback (e.g., tactile, visual, or audible) may be designed into a connector so that the assembler can immediately verify the completion of the coupling operation. However, prior art feedback features for quick connections have relied on internal snap fittings that can be difficult to see in a noisy, vibration-filled environment of an assembly line.SUMMARY OF THE INVENTIONThe invention provides a durable, plastic molded snap feature that wraps 360° around the outside of the quick connect. A high strength type of "industrial plastic" is used which has the required properties of strength, durability and temperature tolerance. The outside snap feature is easily observable as opposed to an inside snap feature that is difficult to observe. The invention is designed so that a visual cue or "red flag" remains visible if the connection is not 100% made. In such a case, the solution is to compress the connection until the snap-fit device engages. In a high volume production line environment, high reliability can be achieved only by using simple human observation, as opposed to using complex electronic sensor devices.The invention is "designed for manufacturing" where the subcomponents are relatively easy to manufacture and assemble. The quick connection achieves high reliability, while being less costly than other currently available solutions.In one aspect of the invention, a quick connect connection for first and second fluid lines includes a receiving member having a first end configured to be mounted to a tip of the first fluid line, a central portion configured to receive a tip of the second fluid line, and a second end defining a cylindrical sleeve configured to be spaced from the tip of the second fluid line. A resilient seal is disposed between the cylindrical sleeve and the tip of the second fluid conduit. A snap lock includes a plurality of molded fixation half shells and a tightening band. Each locating half shell extends longitudinally from a collar portion to a clip portion, and the locating half shells are cylindrically arranged to define a bushing adapted to receive the cylindrical sleeve of the receiving member. The tightening strap is secured over the collar portions to lock the fixation half-shells at the tip of the second fluid line with the clip portions cantilevered over the tip of the second fluid line. Each clip portion includes a hook that snaps over an outside offset on the receiver to connect between the fluid lines so that the resilient seal between the cylindrical sleeve and the tip of the second fluid line is compressed.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a perspective view of a prior art quick connect with an outer clip. FIG. 2 is a cross-section of the quick connect of FIG. 1 without the outer clip. FIG. 3 is a side view of an assembled quick connect according to an embodiment of the invention. FIG. 4 is an exploded view of a fluid conduit with its associated retainer and a ferrule for the embodiment of FIG. 3. FIG. 5 shows the receiving element and the press sleeve installed on the fluid line of FIG. 4. FIG. 6 is an exploded view of a second fluid conduit with its associated snap lock and an O-ring seal for the embodiment of FIG. 3. FIG. 7 is an exploded perspective view of a snap lock wherein the tightening strap includes a spring clip. FIGS. 8 and 9 are an inside plan view and a perspective view of a preferred embodiment of a half-shell fixing. FIGS. 10 and 11 are cross-sectional views of a quick connect of the present invention before and after assembly, respectively. FIG. 12 is a close-up view showing ramp surfaces on a locating half shell and a cylindrical sleeve to facilitate snap-fit connection. Figure 13 is a perspective view of a quick connect of the invention wherein the insertion has not been fully completed. FIG. 14 is a close-up view showing a fully-formed snap connection. FIG. 15 is a side view showing an enlarged slot end between adjacent half-fixing shells to facilitate disassembly of the quick connect.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSReferring to FIGS. 1 and 2, a quick connect system 10 connects the fluid lines 11 and 12 to each other. A pressing sleeve 13 helps to lock a receiving element 14 within the fluid line 11 in a sealed manner. A plastic insert 15 fits into the end of the receiver member 14 to engage an O-ring seal 16 in a resulting groove. Fluid conduit 12 is shown as a metal tube having crimped profiles 17 and 18. The plastic insert 15 includes an annular snap ring portion 19 that snaps over the profile 18 when the conduit 12 is inserted sufficiently far into the receiver 14 so that the O-ring seal 16 is compressed around an outer surface of the fluid conduit 12. A clip 20 has fingers 21 for engaging the crimp profile 17 of the lead 12 and a groove 21 on the receiving member 14 to ensure complete and strong coupling of the quick connect. However, the inside snap action can be difficult to see and the plastic snap components are relatively complex to shape. Further, the use of a separate clip results in additional costs and increased manufacturing difficulties.FIG. 3 shows a quick connect system 25 of the present invention for a motor vehicle fluid system, such as a transmission oil transport circuit for cooling the transmission oil. A first fluid conduit 26 may be a rubber hose to transfer fluid (e.g., oil) to a remote component, and a second fluid conduit 27 may be a metal tube extending from a fluid system component (e.g., a heat exchanger). The quick connect 25 includes respective elements for mounting to respective tips of the conduits 26 and 27 to selectively connect and disconnect the fluid transport circuit.As shown in FIGS. 4 and 5, the first fluid conduit 26 has a tip 26 afor receiving a first end 28 aof a receiving member 28. The receiving member 28 may preferably comprise machined or cast aluminum, and the first end 28 amay include ribs that help maintain a seal when the end 28 ais inserted into the tip 26 a. A second end 28b of the receiving member 28 forms a cylindrical sleeve for interfacing with the other fluid conduit and snap-fitting with other quick-connect components as described below. A ferrule 29 covers the tip 26a and the end 28a of the receiver to provide compression that locks the receiver 28 in place. The pressing sleeve 29 can be installed, for example, by crimping.The fluid conduit 27 has a tip 27a for receiving the other quick connect components. The tip 27a is a metal tube, which is commonly referred to as an end shape. The end form includes crimped profiles 30 and 31 for defining a groove for receiving an O-ring seal 32. the end form further includes a crimped profile 33. To form a socket for receiving the cylindrical sleeve 28a of the receiving member 28, a snap lock is mounted to the end form that includes molded locating half shells 34 and 35 extending longitudinally from respective collar portions 34a and 35a to respective clip portions 34b and 35b. The locating half shells 34 and 35 are cylindrically disposed over the tip 27a to define the sleeve as an annular space adapted to receive the cylindrical sleeve 28a. A tightening strap 36 is secured over the collar portions 34a and 35a to lock the fixation half shells 34 and 35 to the tip 27a. Clip portions 34b and 35b are cantilevered over tip 27a to define the socket. The collar portions 34a and 35a further define an annular groove 37 for receiving the profile 33 for proper alignment and retention of the locating half shells 34 and 35 at the end forming tip 27a. The tension band 36 may comprise a crimped metal band or an elastomeric band to compress the collar portions 34a and 35a to the tip 27a. Alternatively, as shown in FIG. 7, the tightening strap 36 may comprise a spring clip having an inner surface 38 defining an inner diameter slightly less than an outer diameter of the collar portions 34a and 35a, and having tabs 39 that may be manipulated to increase the inner diameter to facilitate assembly over the collar portions 34a and 35a.Referring to FIGS. 8 and 9, a fixation half shell 34 includes a hook 40 configured to provide a snap fit shape by engaging an outboard offset on the receiver member. In the preferred embodiment, the locating half-shells 34 and 35 comprise two semi-cylindrical plastic shells. Preferably, the locating half shells may comprise identical molded plastic elements to reduce the number of components to be molded once. More than two half-fixing shells may be used, as with three half-fixing shells, each spanning 120°. A longitudinal slot 41 may bisect the clip portion 35 bto form multiple clip fingers 42 and 43 to provide additional flexibility that allows additional bending to increase deflection of the hook 40 when needed when mounted over the cylindrical sleeve of the receiver member as described below.As seen in cross-section in Fig. 10, the tubular first end 28a of the receiving member 28 is sized to fit within the inner diameter of the fluid conduit 26. The cylindrical sleeve end 28b has a central portion 45 having an inner diameter adapted to receive the outer diameter of the tip 27a of the fluid conduit 27. The central portion 45 aligns the tip 27a with the receiver member 28 and provides a stable interconnection. An outer portion 46 of the sleeve 28 bhas a larger inner diameter configured to provide an abutment surface for compressing the O-ring 32 to obtain a good seal between the receiving member 28 and the fluid conduit 27. An outer annular surface of the cylindrical sleeve 28b defines an outer offset 47 for receiving the hook 40 of each respective half-shell fixture. The outboard offset 47 may preferably include a radial step as shown. A continuous annular offset may extend over the entire periphery, or separate offsets may be provided for each respective hook. An annular groove 48 may be spaced from the offset 47 to provide a clear demarcation boundary corresponding to the complete engagement of the hook 40, as described below.Figure 11 shows the installed condition of the quick connect wherein the O-ring resilient seal 32 is compressed between the cylindrical sleeve surface 46 and the tip 27a. The quick connect is maintained in a closed state by the locking of the hooks 40a and 40b against the outside offset 47. As shown in detail in Figure 12, the hook 40 includes a ramp surface 50, and the cylindrical sleeve 28b includes a ramp surface 51 to generate a bending force that deflects the clip portion 34b during insertion of the cylindrical sleeve 28b into the socket formed between the tip 27a and the clip portions. When the hook 40 snaps into the desired location over the offset 47, a nose surface 53 of the hook 40 abuts an annular surface 55, and a radial surface 54 abuts the offset 47. The ring surface 55 is preferably provided with a distinctive color (e.g., painted with a red color) to provide visual feedback indicative of the condition of the connection. The visual feedback is a supplement to the tactile and acoustic feedback obtained from the snap action when the hook 40 slides over the offset 47 and returns to an unbent position. The annular groove 48 helps limit the application of paint or other marking substance within the intended ring surface.FIG. 13 shows a partially connected state of the quick connection, wherein the hook 40 is not snapped over the offset 47, so that the annular ring surface 55 remains visible (i.e. is not covered by the clip hook 40). Figure 14 shows a partially fragmentary view wherein the tab 53 of the hook 40 obscures the annular surface 55 after the hook 40 is fully snapped over the offset 47.To disassemble a fully established connection, a special tool may be provided to flex the clip fingers outward sufficiently to expose the locking surface between the hook / s and the offset. Alternatively, the tightening strap compressing the collar portions may be made flexible or otherwise removable to release the cantilevered clip portions from the cylindrical sleeve. To aid removal and avoid the need for any special tools, a slot feature as shown in Figure 15 may be used. A slot 60 between the adjacent locating half-shells 61 and 62 includes an integrally formed notch 63 having a width adapted to receive the blade of a screwdriver for caulking (i.e., bending) adjacent hooks to release the corresponding offset. Preferably, the tension band 64 may be an elastic member (i.e., comprising rubber) to allow pivoting of the fixation half shells to aid removal.

Claims

A quick connect (25) for first and second fluid lines (26, 27) comprising: a receiving member (28) having a first end (28a) adapted to be mounted to a tip (26a) of the first fluid line (26), a central portion adapted to receive a tip (27a) of the second fluid line (27), and a second end (28b) defining a cylindrical sleeve adapted to be spaced from the tip (27a) of the second fluid line (27); a resilient seal (32); and a snap lock comprising: a plurality of shaped locating half shells (34, 35) each of which extends longitudinally from a collar portion (34a, 35a) to a clip portion (34b, 35b), the locating half shells (34, 35) being cylindrically arranged to define a bushing adapted to receive the cylindrical sleeve of the receiving member (28); and a tightening strap (36) adapted to be secured over the collar portions (34a, 35a) to lock the locating half shells (34, 35) at the tip (27a) of the second fluid conduit (27) with the clip portions (34b, 35b) cantilevered over the tip (27a) of the second fluid conduit (27); wherein each of the clip portions (34b, 35b) includes a hook (40) configured to snap over an outside offset (47) on the receiver member (28) to establish communication between the fluid conduits (26, 27), wherein the resilient seal (32) is compressed between the cylindrical sleeve and the tip (27a) of the second fluid conduit (27).The quick connect (25) of claim 1, wherein the outboard offset (47) comprises a radial step on the cylindrical sleeve.The quick connect (25) of claim 1, wherein the fixation half shells (34, 35) comprise identical molded plastic elements.The quick connect (25) of claim 1, wherein the fixation half shells (34, 35) comprise two semi-cylindrical plastic shells.The quick connect (25) of claim 1, wherein the clip portion (34b, 35b) of each half-shell (34, 35) includes a plurality of longitudinally extending clip fingers (42, 43).The quick connect (25) of claim 1, wherein the resilient seal (32) comprises an elastomeric O-ring locked in an annular groove on the second fluid conduit (27).The quick connect (25) of claim 1, wherein the tension band (36) comprises a spring clip.The quick connect (25) of claim 1, wherein after being snapped over the offset (47), the hooks (40) on the clip portions (34b, 35b) occlude an annular surface on the receiver member (28) adjacent the offset, and wherein the annular surface has a distinctive color.The quick connect (25) of claim 1, wherein the second conduit (27) comprises a metal endform tube.The quick connect (25) of claim 9, wherein the metal endform tube has a crimp profile (33), and wherein the collar portions (34a, 35a) include an interior channel that receives the crimp profile (33).The quick connect (25) of claim 9, wherein the metal endform tube includes a pair of crimped profiles (30, 31) defining an annular groove to receive the annular seal (32).The quick connect (25) of claim 1, wherein the clip portions (34b, 35b) and the cylindrical sleeve define mating ramp surfaces (50, 51) to deflect the clip portions (34b, 35b) apart during insertion of the cylindrical sleeve into the bushing.The quick connect (25) of claim 1, wherein adjacent locating half shells (34, 35) define a notch between the adjacent clip portions (34b, 35b) to clamp the adjacent hooks (40) over the offset (47).The quick connect (25) of claim 1, wherein the first fluid conduit (26) comprises a flexible hose, wherein the first end (28a) of the receiving member (28) is insertable into the tip (26a) of the first fluid conduit (26), and wherein the quick connect further comprises a press sleeve (29) mountable over the tip (26a) of the first fluid conduit (26) to compress the tip (26a) against the first end (28a) of the receiving member (28).A motoring fluid system comprising: a first fluid conduit (26) conveying the motoring fluid and having a tip (26a); a second fluid conduit (27) conveying the motoring fluid and having a metal endform tube; and a quick connect (25) connecting the first and second fluid conduits (26, 27) comprising: a receiving member (28) having a first end (28a) mounted to the tip (26a), a central portion adapted to receive the endform tube, and a second end (28b) defining a cylindrical sleeve adapted to be spaced from the endform tube; an elastic seal (32); and a snap lock comprising A) a plurality of shaped locating half shells (34, 35) each of which extends longitudinally from a collar portion (34a, 35a) to a clip portion (34b, 35b), the locating half shells (34, 35) being cylindrically disposed about the metal endform tube to define a bushing adapted to receive the cylindrical sleeve of the receiving member (28), and B) a tightening strap (36) secured over the collar portions (34a, 35a) to lock the locating half shells (34, 35) at the tip (27a) of the second fluid conduit (27) with the clip portions (34b, 35b) cantilevered over a tip (27a) of the second fluid conduit (27); wherein each of the clip portions (34b, 35b) includes a hook (40) that snaps over an outside offset (47) on the receiver member (28) to establish communication between the fluid lines (26, 27), compressing the resilient seal (32) between the cylindrical sleeve and the tip (27a) of the second fluid line (27).The automotive fluid system of claim 15, wherein the end mandrel has a crimp profile (33), and wherein the collar portions (34a, 35a) include an internal channel that receives the crimp profile (33).The automotive fluid system of claim 15, wherein the endform tube has a pair of crimped profiles (30, 31) defining an annular groove that receives the annular seal (32), and wherein the resilient seal (32) comprises an elastomeric O-ring.The automotive fluid system of claim 15, wherein after being snapped over the offset (47), the hooks (40) on the clip portions (34b, 35b) occlude an annular surface on the receiver member (28) adjacent the offset (47), and wherein the annular surface has a distinctive color.The automotive fluid system of claim 15, wherein the clip portions (34b, 35b) and the cylindrical sleeve define mating ramp surfaces (50, 51) to deflect the clip portions (34b, 35b) apart during insertion of the cylindrical sleeve into the bushing.A quick connect (25) comprising: a receiver (28) mounted to a first fluid conduit (26) having a cylindrical sleeve spaced from a second fluid conduit (27); a seal (32) compressed between the receiver (28) and the second fluid conduit (27); and a snap lock having molded fixation half shells (34, 35) cantilevered over the second conduit (27) by a tension band (36); wherein the fixation half shells (34, 35) include hooks (40) that snap over an outside receiver offset (47) to connect the fluid conduits (26, 27) and simultaneously cover an marooned annular surface.

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