TUBE CONNECTORS

Abstract: A connection, for automotive applications, between a rigid tube (14) and a receiver (11) having a socket (12) with an apertured wall, a spigot (16) on the tube end sealingly received in the socket, and a catch (24) on the spigot. The inside of the socket and the outside of the spigot have cooperating portions to ensure that the spigot can only be inserted into the socket in specific orientations. A spring clip (22) engages the spigot catch through the wall aperture of the socket. The spigot can be formed from a sheet metal blank and brazed to the tube, or can be moulded on to the tube.

Description: TUBE CONNECTORS This invention relates to tube connectors, to connections made therewith, and to methods and processes of making the connectors . The connections are intended to be particularly useful in the automotive industry. The tube connections with which this invention is concerned comprise a socket provided with an apertured wall, a spigot sealingly received within the socket, and a catch portion on the spigot accessible through the wall aperture of the socket, at least the inside of the socket and the outside of the spigot being provided with respective cooperating portions whereby to ensure that the spigot can only be inserted into the socket in a limited number, preferably one, of relative orientations, and retainer means engaging the catch portion of the spigot through the wall aperture of the socket. One of the spigot and socket, usually the spigot, is mounted on the end of a tube. Usually, a sealing ring is provided between the spigot and the socket to ensure a sealed connection, if the natural sealing properties of the respective materials are insufficient. The wall aperture of the socket is of course located outside the sealing region. The socket, tube and spigot are all preferably substantially circular in cross section, with an exception of the cooperating portions. These may be provided by corresponding projections and recesses on or in the internal surface of the socket and external surface of the spigot, and may be asymmetrically located around the peripheries thereof or of different sizes. The wall aperture in the socket may be a slot, and there are preferably a plurality of such apertures arranged around the socket, so that locking can take place at more than one circumferential location. A pair of parallel slots on opposite sides of the socket are preferred, in a plane substantially perpendicular to the axis of the connection. The locking means may comprise a spring clip, especially a spring wire clip, having a leg retained in a slot in the socket wall, in engagement with the corresponding catch portion on the spigot. The invention is particularly concerned with the spigot portion of the connection. The invention provides two means in particular of forming a spigot tube connector for use in the tube connection described above, including the method of mounting such spigots sealingly on the end of a rigid tube. One method or process comprises forming the spigot by stamping a blank from sheet material, preferably sheet steel, deep drawing the blank, and affixing it to a tube end by brazing, soldering, or welding or the like, or by means of a suitable adhesive. The second method or process comprises forming an external ridge on the tube end, preferably by deforming a circumferential portion of the tube outwardly, whereby to form an anchorage point for moulding a spigot in position thereon. The ridge is preferably not perfectly circular, to prevent rotation of the spigot on a round tube. This can be achieved by forming a circular ridge around the tube with indentations therein. The advantages of the invention include ease of assembly for the tube connection, and economy of manufacture of the component connectors. The use of conventional hose clips is eliminated and the connection is quickly coupled or uncoupled with a spring clip. Positive orientation ensures that the tube can only be coupled to the socket in a proper orientation, which is important in many applications, for example automotive engineering, where angled tubes must be properly directed. The invention will now be further described with reference to the accompanying illustrative drawings, which show non-limiting examples of the invention. In the drawings : Figure 1 is a cross-section through a tube connection made in accordance with the invention; Figure 2 is a perspective view of the receiver incorporating a socket for receiving the tube in the connection shown in Figure 1; Figure 3 is a perspective view of the spigot which is mounted on the tube and received in the socket; Figures 4a to 4f show six consecutive stages in the manufacture of the spigot shown in Figure 3; Figure 5 illustrates a transfer press on which the processes illustrated in Figures 4a to 4f are carried out; Figure 6 is a perspective view of a deformed tube end prior to moulding thereon a spigot connector in accordance with a second embodiment of the invention, as illustrated in Figures 7 to 10; Figure 7 is a longitudinal cross-section through the tube end fitted with the spigot; Figure 8 is a front elevation of the spigot shown in Figure 7; and Figures 9 and 10 are respectively plan and underneath views of the spigot. Referring to Figures 1 to 3, a receiver 11 which is intended to be bolted over an outlet to a container for water or the like in or on a car engine, for example, is provided with an integral socket 12. The receiver may be moulded from plastics material, or may be a metal casting. A steel tube 14 is connected into the receiver by means of a spigot 16 sealingly fastened over the tube end by brazing 18. The tube, spigot and socket are all essentially circular in cross-section. The socket portion of the receiver has two diametrically opposite partially circumferential slots 20 formed therein, and carries a spring wire retainer clip 22 which is approximately U-shaped, having two straight or slightly curved legs which each resiliently engage one of the slots 20. The spigot 16 has corresponding opposite circumferential slots 24 whose edges act as catch portions for the legs of the retainer clip 22 extending chordally through the socket slots 20. The spigot 16 is formed with a body portion 26 in which the catch slots 24 are formed, connected to a narrower nose portion 28 by an inclined shoulder 30. The socket 12 in receiver 11 is provided internally with a square shoulder 32, and a resilient sealing ring 34 is compressed between the respective shoulders in the assembled connection, as shown in Figure 1. The inner surface of the socket is also provided with two diametrically opposite recesses, extending longitudinally into the interior of the socket from the open mouth thereof. These two recesses are a relatively deep and broad recess 36 and a relatively shallow and narrow recess 38. In the assembled connection, the recesses contain respectively a relatively high and broad lug 40 and a relatively low and narrow lug 42 formed on the outside of the spigot 16. The cooperating lugs and recesses serve not only to guide the spigot properly into the socket, and to prevent rotation once it is in the socket, but also to ensure that the spigot can only be inserted into the socket in one relative orientation. The successive illustrations in Figure 4 show the formation of the spigot from a sheet metal blank 44. In Figure 4a, the body 26 of the spigot is formed in a first drawing stage. Figure 4b shows the spigot nose 28, formed in a second drawing stage. Figure 4c shows the nose having been pierced at the bottom of the drawn cup. Figure 4d illustrates the removal of flange 46, which is a residual portion of blank 44 that is no longer required now that the drawing and nose piercing stages are complete. Figure 4e shows the two opposite lugs 40 and 42 having been formed, and Figure 4f illustrates the completion of the spigot formation after piercing the retaining slots 24. Figure 5 illustrates a transfer press 50 in which the operations described in relation to Figure 4 are carried out, the blanks 44 being obtained from a coil of sheet metal strip 52. The press has six separate stages, each with a separate tool corresponding to the six stages of Figure 4. When a blank has completed one stage it is moved to the next stage by pairs of fingers 54 that grip the workpiece, lift it and move it to the next station before returning to their park positions. The tube end connector thus far described is formed from sheet metal. However, in an alternative embodiment, it may be moulded from plastics material directly on to the end of the tube 14. Figure 6 shows how the tube end may be deformed prior to the moulding operation. A circumferential bead is formed close to the tube end by running an appropriately shaped tool around the inner surface of the tube end while the outer part of the tube is supported in a die. This forms ridge 62, into which three equally circumferentially spaced indentations 64 are subsequently formed. This formation provides an anchorage point for the subsequently moulded spigot, preventing both longitudinal and rotational movement on the tube end. The details of the spigot are shown in Figures 7 to 10, and it includes features corresponding to all the functional features of the sheet metal spigot 16, and is sealingly receivable in the same socket 20. of receiver 11. Spigot 66 is formed in a mould in situ on the tube end with a nose portion 68 joined by an inclined shoulder 70 to a body portion 72 which overlies and engages the locating ridge 62 on the end of tube 14. The body is provided with two diametrically opposite lugs, these being a relatively high and broad lug 74 and a relatively low and narrow lug 76. A catch groove 78 around the body of the spigot 66 functions in the same manner as slots 20 in the sheet metal spigot 16 to engage the retaining legs of the wire spring clip 22 when the tube connection is made.

Claims: CLAIMS 1 A tube connection comprising a socket provided with an apertured wall, a spigot sealingly received within the socket, and a catch portion on the spigot accessible through the wall aperture of the socket, at least the inside of the socket and the outside of the spigot being provided with respective cooperating portions whereby to ensure that the spigot can only be inserted into the socket in a limited number of relative orientations, and retainer means engaging the catch portion of the spigot through the wall aperture of the socket; wherein one of the spigot and socket is sealingly mounted on an end of a tube. 2 A tube connection according to claim 1 wherein the said cooperating portions are adapted to ensure that the spigot can only be inserted into the socket in one relative orientation, in which the catch portion on the spigot is accessible through the wall portion of the socket. 3 A tube connection according to claim 1 or claim 2 wherein the spigot has an external shoulder and the socket has an internal shoulder and a sealing ring is compressed between the respective shoulders of the spigot and the socket. 4 A tube connection according to any one of the preceding claims wherein the socket, tube and spigot are all substantially circular in cross section, with the exception of the cooperating portions. 5 A tube connection according to any one of the preceding claims wherein the cooperating portions comprise a corresponding projection and recess on or in the internal surface of the socket and external surface of the spigot. 6 A tube connection according to claim 5 wherein the cooperating portions are provided by at least two corresponding projections and recesses on or in each of the internal surface of the socket and external surface of the spigot, and are asymmetrically located around the peripheries of the socket and spigot respectively or are of different sizes, whereby to ensure that the spigot can only be inserted into the socket in one relative orientation. 7 A tube connection according to any one of the preceding claims wherein the wall aperture in the socket comprises a circumferentially extending slot. 8 A tube connection according to any one of the preceding claims wherein there are a plurality of catch portions and wall apertures arranged around the spigot and socket respectively, so that locking can take place at more than one circumferential location. 9 A tube connection according to claim 8 wherein the said wall apertures comprise a pair of parallel slots on opposite sides of the socket, in a plane substantially perpendicular to the axis of the connection. 10 A tube connection according to claim 7 or claim 9 wherein the locking means comprise a spring clip, especially a spring wire clip, having a leg retained in a said slot in the socket wall, in engagement with the corresponding catch portion on the spigot. 11 The spigot of the tube connection claimed in any one of the preceding claims, sealingly mounted on the end of a rigid tube. 12 A spigot according to claim 11 wherein the spigot is formed from a deep drawn sheet metal blank and affixed sealingly to the tube end by brazing, soldering, welding, or by means of an adhesive. 13 A spigot according to claim 11 wherein the spigot is moulded sealingly on to an anchorage point formed on the tube end. 14 A method of forming a spigot tube connector for use in the tube connection claimed in any one of claims 1 to 10 which comprises stamping a blank from sheet metal, deep drawing the blank to form a cup having a nose, piercing the nose, forming a said cooperating portion on the outside of the cup wall, and forming a said catch portion on the cup, thereby forming the spigot, and sealingly mounting the spigot on to a rigid tube end. 15 A method according to claim 14 wherein the step of forming the catch portion comprises piercing a slot in the cup wall. 16 A method of forming a spigot tube connector for use in the tube connection claimed in any one of claims 1 to 10 which comprises forming an external ridge on a rigid tube end, preferably by deforming a circumferential portion of the tube outwardly, whereby to form an anchorage point, and moulding a spigot sealingly in position thereon. 17 A method according to claim 16 wherein the ridge is formed on a round tube by forming a circular ridge around the tube with indentations therein.

Inventors: HALSALL JOHN ANTHONY SIDNEY, SNARE DAVID MICHAEL, HALSALL, JOHN, ANTHONY, SIDNEY, SNARE, DAVID, MICHAEL
Applicants: HALSALL JOHN ANTHONY SIDNEY, SHALIBANE PLC, SNARE DAVID MICHAEL, HALSALL, JOHN, ANTHONY, SIDNEY, SNARE, DAVID, MICHAEL
Application year: 1998
Main classification: F16L37
IPC codes: F16L37