Abstract:
A twist lock assembly includes an annular first flange at an open end of a first conduit attached to a fluid receiving component. The first flange has an alignment slot and at least one locking slot formed therein. A fluid conducting conduit has an annular second flange at an open end thereof. The second flange includes an alignment tab formed thereon. A locking ring rotatably mounts on the second flange and includes at least one locking tab formed thereon. When the first flange is attached to the component, the alignment tab engages the alignment slot and the at least one locking tab is aligned with the at least one locking slot. Rotating the locking ring relative to the second flange draws the first and second flanges into airtight engagement and locks the conduit to the component.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates in general to air induction and distribution systems and, in particular, to a twist lock assembly for an air induction and distribution system.  
         [0002]     Air induction and distribution systems, such as those for automotive internal combustion engines, are well known. A typical automotive internal combustion engine air induction system includes a plurality of connections between various components of the system including, but not limited to, an air cleaner assembly, a resonator, and a throttle body. The types of connections utilized typically require the use of hand tools to assemble in order to provide an airtight connection at the joints. Any connection less than an airtight connection reduces the efficiency of the air induction and distribution system.  
         [0003]     It would be desirable to provide a means for sealing the joints on connections in an air induction and distribution system and the like that can seal the joints in an airtight manner and does not require the use of power tools or the like for assembly.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention concerns a twist lock assembly for connecting a fluid conducting conduit to a fluid receiving component. The twist lock assembly includes an annular first flange adapted to be attached to a fluid receiving component and surrounding an opening in the component. The first flange has an alignment slot and at least one locking slot formed in a periphery thereof. A fluid conducting conduit having an open end includes an annular second flange attached to the open end of the conduit. The second flange includes a radially inwardly extending alignment tab formed thereon. A locking ring rotatably mounts on the second flange and includes at least one radially inwardly extending locking tab formed thereon. When the first flange is attached to the component and the first and second flanges are abutting and concentric, the alignment tab engages the alignment slot and the at least one locking tab is aligned with the at least one locking slot. Rotating the locking ring relative to the second flange draws the first and second flanges into airtight engagement and locks the conduit to the component. Preferably, a sealing bead is formed on a sealing surface of the second flange for assisting in the airtight engagement between the first and second flanges. Preferably, the locking ring is rotated approximately 110 degrees to bring the first and second flanges into airtight engagement.  
         [0005]     The twist lock assembly in accordance with the present invention advantageously provides a greatly improved ability to prevent leakage of evaporative emissions through the joint, which provides an improved capability to meet PLEV and ZLEV emission requirements without the cost of a hydrocarbon absorber. The twist lock assembly reduces turbulence and improves the quality of the air flow path past the twist lock assembly by having the same diameter on both sides of the joint as there is no stepped surface therein and allows for shorter conduits since the flow path is not interrupted by the connection. In addition, the twist lock assembly automatically aligns the first and second flanges, eliminating the need to stretch the end of the duct over the mating part and then tightening as a separate operation. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]     The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:  
         [0007]      FIG. 1  is a perspective view of a partially assembled twist lock assembly in accordance with the present invention;  
         [0008]      FIG. 2  is a side view of a first conduit in accordance with the present invention;  
         [0009]      FIG. 3  is an end view of the first conduit shown in  FIG. 2 ;  
         [0010]      FIG. 4  is an end view of a second conduit and locking ring in accordance with the present invention;  
         [0011]      FIG. 5  is a partial cross sectional side view of the conduit and locking ring shown in  FIG. 4 ; and  
         [0012]      FIG. 6  is an end view of an alternative embodiment of a first conduit in accordance with the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0013]     Referring now to  FIG. 1 , a twist lock assembly in accordance with the present invention is indicated generally at  10 . The twist lock assembly  10  includes a first conduit  12  and a second conduit  14  having a locking ring  16  rotatably mounted thereon for assisting in the engagement of the first conduit  12  and the second conduit  14 , discussed in more detail below.  
         [0014]     Preferably the first conduit  12  is adapted to be attached to an air receiving engine component  9 , best seen in  FIG. 2 , including, but not limited to, an air cleaner, a resonator, and a throttle body. The first conduit  12  is an air receiving conduit and the second conduit  14  is an air supplying conduit adapted to conduct the air from a source such as an air intake. Alternatively, the first  12  and second  14  conduits are any type of plumbing conduits wherein an airtight seal, discussed in more detail below, is desired for transferring fluid therebetween including, but not limited to, air filters, ducts, mass air flow meters, throttle bodies, and turbo inlets.  
         [0015]     Referring now to  FIGS. 2 and 3 , the first conduit  12  is shown in a side view and an end view. The first conduit  12  includes an outside surface  20  and an inside surface  22  and is preferably constructed of a hard plastic material or similar material. The first conduit  12  includes a radially outwardly extending annular first flange  18  on an end  19  thereof. The first flange  18  includes a sealing surface  23  generally perpendicular to a longitudinal axis  11  of the first conduit  12  and an oppositely facing locking surface  30  generally parallel with the sealing surface  23 . The surfaces  23  and  30  are separated by an axial thickness  24  of the first flange  18 . A plurality of locking slots or apertures  26  are formed generally equidistant about a circumference of the first flange  18 , each of which extends through the surfaces  23  and  30 . Preferably, three locking apertures  26  are formed in the first flange  18 . Intermediate a pair of the apertures  26  is formed an alignment slot  27 .  
         [0016]     A plurality of ramped surfaces  28  that correspond in number to the number of locking apertures  26  is formed in the first flange  18 . Each of the ramped surfaces  28  is formed adjacent a corresponding locking aperture  26  and the ramped surfaces  28  connect the sealing surface  23  and the locking surface  30 . A stop member  32  extends axially outwardly from the locking surface  30  adjacent a one of the locking apertures  26 . A cam locking member  34  also extends axially outwardly from the locking surface  30  between a ramped surface  28  and the stop member  32 .  
         [0017]     Referring now to  FIGS. 4 and 5 , the second conduit  14  and the locking ring  16  are shown in a side view and an end view. The second conduit and the locking ring  16 , when attached, form a pre-assembly, indicated generally at  15 . The second conduit  14  includes an outside surface  40  and an inside surface  42  and is preferably constructed of a soft rubber material or similar material. The second conduit  14  includes a second radially outwardly extending annular flange  44  on an end thereof. The second flange  44  includes a sealing surface  52  generally perpendicular to a longitudinal axis  13  of the second conduit  14  and a surface  51  opposite the sealing surface  52 . A raised annular sealing bead  54  is formed on the sealing surface  52 . The sealing bead  54  is preferably an integrally formed rubber sealing member having a generally semicircular cross section similar to a sectioned O-ring. Preferably, the sealing bead  54  is situated intermediate a radially outer portion of the sealing surface  52  and a radially inner portion of the sealing surface  52 . Alternatively, the sealing bead  54  only extends on a portion of the surface  52 , such as at four equal arcuate intervals. An alignment tab  50  extends axially from the sealing surface  52  of the second flange  44  at a radially outer position relative to the sealing bead  54 .  
         [0018]     The locking ring  16  is preferably formed of a hard plastic material including, but not limited to the hard plastic material of the first conduit  12 . The locking ring  16  is rotatably mounted on the second flange  44  of the second conduit  14  such that a radially inner surface  46  of the locking ring is spaced apart from a radially outer surface  43  of the second flange  44 . The locking ring  16  includes an outer axial surface  45  and an inner axial surface  47  connected by the radially inner surface  46 . Axial movement of the locking ring  16  relative to the flange  44  is constrained by the loose engagement of the surfaces  45 ,  46 , and  47  of the locking ring and the surfaces  43 ,  51 , and  52  of the flange  44 . The locking ring  16  includes a plurality of radially inwardly extending locking tabs  48  spaced generally equidistant about a circumference thereof.  
         [0019]     When the first conduit  12  and the second conduit  14  are to be attached to form the assembly  10 , and the first flange  18  and the second flange  44  are abutting and concentric, the alignment tab  50  is placed adjacent the alignment slot  27 , which also aligns the locking tabs  48  of the locking ring  16  with the locking apertures  26  of the first flange  18 . The locking ring  16  is then rotated in an engaging direction  36  about the longitudinal axis  13  of the second conduit  14 . The second conduit  14 , however, remains stationary as the locking ring  16  is rotated because the alignment tab  50  retains the second conduit  14  in relation to the first conduit  12  by engaging with a surface  27   a  in the alignment slot  27 .  
         [0020]     As the locking ring  16  rotates in the engaging direction  36 , the locking tabs  48  engage with the respective ramped surfaces  28 , moving the locking  16  along the ramped surfaces  28  from the sealing surface  23  to the locking surface  30 . The movement of the locking ring  16  also moves the sealing surface  52  of the second conduit  14  closer to the sealing surface  23  of the first conduit  12 . The locking ring  16  and the sealing surface  52  have now moved toward the sealing surface  23  a distance substantially equal to the thickness  24  of the first flange  18 . The sealing bead  54 , therefore, is compressed between the opposed sealing surfaces  32  and  52 , bringing the sealing surfaces  52  and  23  into an airtight engagement.  
         [0021]     After the sealing surfaces  52  and  23  are brought into airtight engagement, the locking ring  16  is rotated further in the engaging direction  36  such that one of the locking tabs  48  engages with a leading edge  34   a  of the cam lock member  34 . The leading edge  34   a  has a ramped surface to assist in engaging the locking tab  48 . The cam lock member  34  includes a radially outer surface  34   c  that increases in diameter from the leading edge  34   a  to a trailing edge  34   b . As the locking ring is rotated, the locking ring  16  deforms radially outwardly, which allows the locking tab  48  to travel along the radially outer surface  34   c  to a position beyond the trailing edge  34   b , where the locking ring  16  returns to its original orientation and the locking tab engages with the inside surface  22 . The locking tab  48  is now disposed between the cam lock member  34  and the stop member  32 , which locks the locking ring  16  and second conduit  14  to the first conduit  12 . The locking tab  48  disposed in this position ensures that the sealing bead  54  remains compressed and the airtight engagement between the sealing surfaces  52  and  23  remains intact.  
         [0022]     Alternatively, the locking ring  16  and the second conduit  14  are releasably locked to the first conduit  12 . There is shown in  FIG. 6 , an alternative embodiment of a first conduit  12 ′ and first flange  18 ′. The first conduit  12 ′ includes an elongated cam locking member  34 ′ having a leading edge  34   a ′, a trailing edge  34   b ′, and a radially outer surface  34   c ′. The trailing edge  34   b ′ has a ramped surface similar to the ramped surface of the leading edge  34   a  and  34   a ′. The surface  34   c ′ increases in diameter from the leading edge  34   a ′ to a point approximately midway between the leading edge  34   a ′ and the trailing edge  34   b ′, after which point it decreases in diameter to the trailing edge  34   b ′. After the locking ring  16  and the second conduit  14  have been locked to the first conduit  12 ′, the locking ring  16  and the second conduit  14  may be unlocked or released from the first conduit  12 ′ by rotating the locking ring  16  in a disengaging direction  38 . A force is applied to the locking ring  16  to rotate the locking tab  48  in the disengaging direction  38  beyond the trailing edge  34   b ′ and engage the outer surface  34   c ′. The second conduit  14  remains stationary as the locking ring  16  is rotated because the alignment tab  50  retains the second conduit  14  in relation to the first conduit  12  by engaging with a surface  27   b  in the alignment slot  27 . As the locking ring is rotated, the locking ring  16  deforms radially outwardly, which allows the locking tab  48  to travel along the radially outer surface  34   c ′ to a position beyond the trailing edge  34   b ′, where the locking ring  16  returns to its original orientation and the locking tab engages with the inside surface  22 . The locking tab  48  is now interposed between the cam lock member  34 ′ and the locking aperture  26  and is then rotated further to travel along the ramped surface  28 , along with the other locking tabs  48  to the respective locking apertures  26  and removed from the first conduit  12 .  
         [0023]     The ramped surfaces  28  are designed such that the sealing bead  54  is compressed by the same predetermined distance, substantially equal to the thickness  24  of the first flange  18 , each time the locking ring  16  and second conduit  14  are attached to the first conduit  12  or  12 ′. This consistency ensures that the connection between the conduits  12  or  12 ′ and  14  is repeatable and thus the connection remains airtight for a substantial number of engagement and disengagement cycles.  
         [0024]     In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.