Patent Document

This application is a continuation-in-part of copending application Ser. No. 09/151,480 filed on Sep. 10, 1998, which is a continuation of Ser. No. 08/673,574 filed on Jul. 1, 1996. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to fluid line systems which include quick connector couplings, and more particularly to a retainer for a quick connector coupling having tolerance for a wide band of male tube dimensions. 
     In automotive and other fields, quick connector couplings, which generally include a male tube received and sealingly retained in a female connector body, are often utilized to provide a fluid connection between two components or conduits, thus establishing a fluid line between the two components. Use of quick connector couplings is advantageous in that a sealed and secured fluid line connection may be established quickly and easily. 
     A number of methods and mechanisms exist for securing the male tube and female connector body of a quick connector coupling together. One retention mechanism, which is the subject of the present invention, involves use of a plastic retainer disposed within the connector body. 
     The retainer has a base ring disposed inside of the connector body which is connected to outer portions aligned with, and positioned inside of, the connector body entrance. Compressive members extend from the outer portions to positions spaced from the base ring. The outer ends of the compressive members abut a radial shoulder formed within the connector body to secure the retainer inside of the connector body, and an enlarged upset formed on the inserted male tube is captured in the space between the compressive members and base ring to secure the tube in the connector body. 
     Conventional retainer designs can tolerate only a narrow band of male tube dimensions. Introduction of new materials, suppliers and manufacturing methods, however, have led to use of male tubes having a broad and varying band of dimensions. Conventional retainers are often not able to accommodate tubes of varying dimensions. Consequently, different sizes of retainers must often be utilized for tubes having just minor differences in dimension. Significant expense results, since a new mold must be constructed for each retainer variation. Management, tracking and identification of multiple retainer variations for multiple customers also adds to complexity and expense. 
     The present invention addresses this problem by providing an improved retainer design which can tolerate a wider band of male tube dimensions. 
     SUMMARY OF THE INVENTION 
     The present invention is directed toward a connector for receiving a tube end having at least one radially enlarged upset. The connector comprises a hollow female connector body and a retainer disposed in the connector body. The retainer has an annular inner base ring defining a cylindrical surface to receive the tube end. The retainer further defines compressive members. The base ring has a limit surface facing the compressive members and a chamfer intersecting the limit surface and the cylindrical surface. The compressive members define an inner diameter and a space between the limit surface and the compressive members for securing the radially enlarged upset in the connector body. The inner diameter of the compressive members is at least as large as the diameter of the intersection of the chamfer with the limit surface. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a sectional view of a prior art quick connector coupling; 
     FIG. 2 is a partial sectional view of another prior art quick connector coupling; 
     FIG. 3 is an enlarged partial sectional view of a male tube captured by a retainer; 
     FIG. 4 is an enlarged partial sectional view of another male tube captured by a retainer; 
     FIG. 5 is a perspective view of the type of retainer of the present invention; 
     FIG. 6 is an enlarged partial sectional view of a male tube captured by a retainer according to the present invention; 
     FIG. 7 is an enlarged partial sectional view of another male tube captured by a retainer according to the present invention; 
     FIG. 8 is a sectional view of a set of mold dies and mold core pin for forming a retainer with the compressive members having an inner diameter approximately as large as the diameter of the intersection of the chamfer with the limit surface; 
     FIG. 9 is a sectional view of the set of mold dies and mold core pin of FIG. 8 after injection of plastic material into cavities defined in the set of mold dies and mold core pin; 
     FIG. 10 is a sectional view of the set of mold dies and mold core pin of FIG. 9 with the core pin being removed from the mold dies; 
     FIG. 11 is a sectional view of the mold dies of FIG. 10 with the mold dies being removed from the resultant retainer; and 
     FIG. 12 is a sectional view of an alternative set of mold dies and mold core pin for forming a retainer with compressive members having an inner diameter larger than the diameter of the intersection of the chamfer with the limit surface. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     A prior art quick connector coupling  10  is illustrated in FIG.  1 . Coupling  10  is comprised of a generally cylindrical female connector body  12  and a male tube  14 . Connector body  12 , in use, is connected to flexible hose or another system component. Likewise, male tube  14  forms a part of a fluid line system. Connector body  12  and tube  14  are connectable to form a permanent, but severable, joint in the fluid line. 
     Tube  14  includes a radially enlarged upset  16  formed a given distance from tube end  18 . Upset  16  defines an abutment wall  20  formed perpendicular to the outside surface of tube  14  facing away from tube end  18 , and a sloped wall  22  facing tube end  18 . 
     A plastic retainer  24  is disposed within connector body  12 . Retainer  24  is comprised of base ring  26 , outer portions  28  and compressive members  30  extending from outer portions  28  toward base ring  26 . Connecting leg portions  32  join base ring  26  and outer portions  28 . The coupling illustrated in FIG. 1 also includes an indicator member  34  receivable in an indicator pocket  36 . The indicator features are not part of the present invention but are explained in detail in U.S. Pat. No. 5,499,848. 
     Compressive members  30  each include at one end, a first locking surface  38  facing away from base ring  26 , and at an opposite end, a second locking surface  40  facing base ring  26 . First locking surfaces  38  abut a shoulder  42  formed in connector body  12  to secure retainer  24  inside of connector body  12 , and second locking surfaces  40  abut abutment wall  20  of upset  16  to capture upset  16  in the space between compressive members  30  and base ring  26 , and thereby secure male tube  14  in connector body  12 . Compressive members  30  may be spread apart to permit insertion of tube  14  into connector body  12  to a secured position (illustrated), and conversely, to permit release of tube  14  (with use of an appropriate release tool). 
     Base ring  26  includes a central opening, defined by cylindrical wall  44 , through which tube  14  passes and fits closely. A limit surface  46  is perpendicular to cylindrical wall  44  and, together with locking surfaces  40  of compressive members  30 , defines the space within which upset  16  is captured. As is evident in FIG. 1, contact between sloped surface  22  of upset  16  and limit surface  46  of base ring  26  limits movement of upset  16  within this space. Conical flange  48  is formed on base ring  26  opposite limit surface  46 . If retainer  24  and tube  14  are pressed further into connector body  12 , conical flange  48  fits into conical cavity  50  of spacer  52  which is press-fit into connector body  12 . 
     FIG. 2 illustrates a similar prior art coupling  60 . Coupling  60  includes a connector body  62 , a male tube  64  and a retainer  66 . An O-ring seal  68  is held in connector body  62  by a spacer  70 , and a hose  72  is received over the end of connector body  62 . Retainer  66  is of the same type as the retainer shown in FIG.  1 . It includes a base ring  74  and outer portions  76  joined to base ring  74  by connective leg portions (not shown) similar to leg portions  32  of FIG.  1 . Compressive members  78  extend from outer portions  76  toward base ring  74 . First locking surfaces  80  of compressive members  78  abut shoulder  82  to secure retainer  66  in connector body  62 , and second locking surfaces  84  abut upset  86  formed on tube  64  to secure tube  64  in connector body  62 . 
     Upset  86  differs from upset  16  of FIG.  1 . It defines two abutment walls  88 , each of which is substantially perpendicular to the outer surface of tube  64 . Moreover, upset  86  is in an extremely tight fit in the space between compressive member locking surfaces  84  and perpendicular limit surface  90  of base ring  74 . It has no range of movement within its captured space. 
     FIGS. 1 and 2 have been included and described herein because they are exemplary of retainer design and tolerance concerns relative to male tubes. Retainer  24  of FIG. 1 could accept a male tube having a slightly wider upset or with abutment walls of slightly different slope. Retainer  66  of FIG. 2, by contrast, is at its maximum tolerance. Upset  86  could not be widened, nor could any slope or radii be added to its abutment walls  88 . FIGS. 1 and 2 also illustrate that male tube dimensions and configurations, particularly regarding the upsets, are not uniform. A tube having an upset of the same nominal width as upset  86  in FIG. 2, but having a sloped wall or radii similar to wall  22  of upset  16  in FIG. 1, would not fit properly within retainer  66  of FIG. 2. A retainer having a greater spacing between the base ring and compressive members would be required. 
     This problem is magnified in FIGS. 3 and 4. FIG. 3 depicts an upset  100  of a tube  102  captured by a retainer  104 . The remaining details of the coupling, which  142  formed on male tube  144 . Base ring  132  has a central opening defined by cylindrical surface  146 , and a limit surface  148  facing compressive members  136  and perpendicular to cylindrical surface  146 . 
     Base ring  132  and compressive members  136  are modified to provide tolerance for an expanded band of male tube dimensions. A chamfer  150  is formed between limit surface  148  and cylindrical surface  146  to provide the ability to accommodate sloped surfaces on upsets. Chamfer  150  is formed during the injection molding process by enlarging the outer diameter of the mold core pin and providing the core pin with a conical tip. A base ring formed without a chamfer, as depicted in phantom lines, could not accommodate upset  142 . 
     Inner diameter portions  152  of compressive members  136 , shown in phantom lines, are also removed as a result of use of an enlarged diameter mold core pin. Enlarging the diameter of the mold core pin to provide a chamfer on the base ring had not been considered a viable option before the present invention because, as shown, it results in increased spacing between the compressive members. Contact between the compressive members and the external (non-upset portions) surface of the male tube is lost. Applicant has found that this loss of contact does not significantly reduce the strength of the retainer. Moreover, as seen particularly in FIG. 7, enlargement of the compressive member inner diameter provides further increased tolerance for male tubes of varying dimensions. Furthermore, FIGS. 6 and 7 depict compressive members having inner diameters  20  approximately as large as the diameter of the intersection of the chamfer with the limit surface. 
     The retainer of the present invention is molded as follows and as illustrated in FIGS. 8-11. FIG. 8 illustrated a sectional view of a set  200  of mold dies  202  and mold correspond in function to the couplings of FIGS. 1 and 2, are not illustrated. Upset  100  is held in the space between compressive member locking wall  106  and base ring limit wall  108 . Upset  100  includes abutment walls  110  which are substantially perpendicular to the outside surface of tube  102 . Sloping wall portions  112  join walls  102  with the tube surface. Though the width of upset  100  is significantly less than the spacing between retainer walls  106  and  108 , wall portions  112  cause contact between the upset and retainer base ring and compressive members, effectively pushing retainer  104  to the limit of its tolerance. 
     In FIG. 4, the retainer  104  of FIG. 3 is utilized, but a tube  120  having an upset  122  of different dimensions is introduced. Upset  122  is slightly wider than upset  100  of FIG. 3, and includes a more pronounced sloping wall portion  124 . The result is that upset  122  does not fit properly in the space between retainer surfaces  106  and  108 . Corner portions  126  and  128  of, respectively, the retainer base ring and compressive members, impinge on the upset. Hence, a slight change in the dimensions of the male tube has rendered retainer  104  ineffective. 
     FIG. 5 is a perspective view of the type of retainer of the present invention. The present invention, shown in FIGS. 6 and 7, provides a retainer design having tolerance for a wider band of tube dimensions. Retainer  130  of FIG. 6 is formed of injection molded plastic and has a base ring  132 , outer portions  134  and compressive members  136  (one is shown). Outer portions  134  are connected to base ring  132  by connective leg portions (not shown) similar to leg portions  32  of the retainer of FIG.  1 . First locking surface  138  of compressive member  136  abuts a shoulder of the connector body (not shown) to secure the retainer in the connector body. Second locking surface  140  facing base ring  132  abuts upset core pin  204  for forming a retainer with the compressive members having an inner diameter approximately as large as the diameter of the intersection of the chamfer with the limit surface. The mold core pin  204  is located in the radial center-line or the core of the mold dies  202 . The mold core pin  204  has a first cylindrical portion  206 , an enlarged cylindrical portion  208  and a conical portion  210  located between the first cylindrical portion  206  and the enlarged cylindrical portion  208 . 
     The set  200  of mold dies and mold core pin defines a cavity  212  for forming the base ring  132 , cavities  214  for forming the compressive members  136  and cavities (not shown) for forming the remainder of the resultant retainer  130 . The cavity for forming the base ring  132  has an annular surface  216  for forming the limit surface  148  of the base ring  132 . The annular surface  216  is axially in-line with the intersection of the enlarged cylindrical portion  208  and the conical portion  210  of the mold core pin  204 . 
     FIG. 9 illustrates a sectional view of the set of mold dies and mold core pin after injection of plastic material into the cavities defined in the set of mold dies and mold core pin. The annular surface  216  of the mold dies  202  forms the limit surface  148  of the base ring  132 . The first cylindrical portion  206  of the mold core pin  204  forms the cylindrical surface  146  of the base ring  132 . The conical portion  210  of the mold core pin  204  forms the chamfer  150  of the base ring  132 . The enlarged cylindrical portion  208  of the mold core pin  204  forms the inner surfaces of the compressive members  136 . Upon the injected plastic material solidifying sufficiently, the mold core pin  208  in removed axially outward along the radial center-line in the direction of arrow  218  as illustrated in FIG.  10 . Thereafter, the mold dies  202  are removed from the resultant retainer  130  in the direction of arrows  220 ,  222  and  224  as illustrated in FIG.  11 . Since the intersection of the chamfer  150  with the limit surface  148  of the resultant retainer  130  is defined by the intersection of the conical portion  210  of the mold core pin  204  with the enlarged cylindrical portion  208  of the mold core pin  204  and the inner surfaces of the compressive members  136  are defined by the enlarged cylindrical portion  208  of the mold core pin  204 , the resultant retainer  130  has compressive members  136  with an inner diameter approximately as large as the diameter of the intersection of the chamfer  150  with the limit surface  148 . 
     FIG. 12 illustrates the sectional view of an alternative set  250  of mold dies  252  and mold core pin  254  for forming a retainer  256  with compressive members  258  having an inner diameter larger than the diameter of the intersection of the chamfer  260  with the limit surface  262  of a base ring  259 . The mold core pin  254  of the alternative set  250  of mold dies and mold core pin has an enlarged cylindrical portion  266  having a proportionately larger diameter than the diameter of the enlarged cylindrical portion  208  of the core pin  204  disclosed in the previously disclosed set  200  of mold dies and mold core pin. With the enlarged cylindrical portion  266  having a proportionately larger diameter, the conical portion  268  likewise is proportionately longer axially. Therefore, the intersection of the enlarged cylindrical portion  266  and the conical portion  268  of the mold core pin  254  is not axially in-line with annular surface  270  of mold dies  252  as in the previously disclosed set  200  of mold dies and mold core pin. Rather, the intersection of the enlarged cylindrical portion  266  and the conical portion  268  of the mold core pin  254  is axially outward of the annular surface  270  of the mold dies  252 . As the result, the compressive members  258  of the resultant retainer  256  have an inner diameter larger than the diameter of the intersection of the chamfer  260  with the limit surface  262 . 
     FIG. 7 depicts another embodiment of the present invention. Retainer  160  again includes a base ring  162  and compressive members  164 . Chamfer  166  is formed between cylindrical wall  168  and perpendicular limit wall  170  during the injection molding process through use of an enlarged diameter core pin as described above. Chamfer  166  is formed at a reduced angle relative to wall  168 , as compared to the embodiment of FIG.  6 . Portions  172  of compressive members  164  are also removed through use of the core pin. As can be seen, the relatively exotic upset  174  would cause interference within retainer  160  without application of the principles of the present invention. 
     Various features of the present invention have been explained with reference to the embodiments shown and described. Of course, modification may be made to the described embodiments without departing from the spirit and scope of the invention as represented by the following claims.

Technology Category: b