Abstract:
A composite air intake manifold assembly adapted for use with an internal combustion engine includes an upper half shell formed from a polymer and a lower half shell formed from a polymer and joined to the upper half shell to define a housing having an internal cavity. The internal cavity includes at least a pair of spaced apart generally cylindrical shaped air intake runners, each of the runners including an opened air intake end adapted to receive atmospheric air, and an opened air inlet end adapted to be connected to an associated an air inlet side of a cylinder head of the internal combustion engine. The housing of the composite air intake manifold assembly includes at least one of an integrally molded sensor connection and an integrally molded vacuum tap. The method for producing the composite air intake manifold assembly includes the steps of: (a) providing an upper half shell formed from a polymer; (b) providing a lower half shell formed from a polymer; and (c) joining the upper half shell to the lower half shell to define a housing having an internal cavity, the housing including at least one of an integrally molded sensor connection and an integrally molded vacuum tap.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates in general to vehicle engines and in particular to an improved composite intake manifold assembly for use in such a vehicle engine and method for producing the same. 
     An intake manifold assembly of a multi-cylinder engine includes a plurality of branched air passageways or ducts. Each of the air passageways defines a generally tubular runner having an air intake port and an opposite air inlet port. The air intake port of the runner is connected to an associated plenum which supplies atmospheric, turbo, or supercharged air to the runner intake port, and the air inlet port is connected to a flange which is connected to an associated inlet port of each cylinder head of the engine to supply the air from the runner to each cylinder head. Conventional intake manifold assemblies are constructed of cast iron, magnesium, aluminum, and plastic. 
     A typical aluminum intake manifold assembly is produced entirely by conventional casting process. These manifolds typically include a plurality of tubes disposed having first ends connected with the outlet holes of an air intake plenum, and second opposite ends connected with the associated holes of a flange member which is adapted for mounting to a cylinder head of the engine. Since the tubes are usually U-shaped, the manifold cannot be cast in one piece but rather must be cast in two sections, with one section comprising a length of the tubing cast integrally with the plenum and the other section comprising the remaining length of the tubing cast integrally with the flange member. The halves must then be joined together with bolts and a gasket or other suitable hardware to complete the manifold, further adding to the cost and complexity of the manifold. 
     A typical plastic multi-piece manifold assembly includes an upper half shell and a lower half shell which are joined together by a welding process. In some instances the plastic multi-piece manifold assembly includes one or more inner shell pieces which are disposed within the upper and/or lower half shells. The inner shell can be lower partial inserts which are secured to lower half shell; upper partial inserts which are secured to the upper half shell, or both lower and upper partial inserts which are secured to the respective lower and upper half shells. The inserts are typically joined to the associated half shell by a conventional heat staking process or welding process. In some instances, a plurality of individual blow molded tubes are disposed within the upper and lower half shells and joined thereto by a conventional heat staking process. In both types of constructions, the inserts or the inserts in cooperation with upper or lower half shells define a corresponding number of runner paths through which air is supplied to the associated cylinder head of the engine. 
     SUMMARY OF THE INVENTION 
     This invention related to an improved composite intake manifold assembly for use in a vehicle engine and method for producing the same. The composite intake manifold assembly includes an upper half shell formed from a polymer and a lower half shell formed from a polymer and joined to the upper half shell to define a housing having an internal cavity. The internal cavity includes at least a pair of spaced apart generally cylindrical shaped air intake runners, each of the runners including an opened air intake end adapted to receive atmospheric air, and an opened air inlet end adapted to be connected to an associated an air inlet side of a cylinder head of the internal combustion engine. The housing of the composite air intake manifold assembly includes at least one of an integrally molded throttle cable bracket, an integrally molded sensor connection, and an integrally molded vacuum tap. The method for producing the composite air intake manifold assembly includes the steps of: (a) providing an upper half shell formed from a polymer; (b) providing a lower half shell formed from a polymer; and (c) joining the upper half shell to the lower half shell to define a housing including at least one of an integrally molded sensor connection and an integrally molded vacuum tap. As a result of this, the costs associated with a brass fitting typically used for the associated sensor connection and vacuum taps can be eliminated. 
    
    
     Other advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, when read in light of the accompanying drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a first embodiment of a composite intake manifold assembly constructed in accordance with the present invention. 
     FIG. 2 is a plan view of an upper half shell used in the composite intake manifold assembly illustrated in FIG.  1 . 
     FIG. 2A is an enlarged plan view of a portion of the upper half shell shown in FIG.  2 . 
     FIG. 3 is a plan view of a lower half shell used in the composite intake manifold assembly illustrated in FIG.  1 . 
     FIG. 3A is an enlarged plan view of a portion of the lower half shell shown in FIG.  3 . 
     FIG. 4 is a perspective view of a one piece inner shell used in the composite intake manifold assembly illustrated in FIG.  1 . 
     FIG. 4A is an enlarged view of a portion of the one piece inner shell shown in FIG.  4 . 
     FIG. 5 is a plan view of the one piece inner shell illustrated in FIGS. 1 and 4. 
     FIG. 5A is an enlarged plan view of a portion of the one piece inner shell shown in FIG.  5 . 
     FIG. 6 is a sectional view of the composite intake manifold assembly illustrated in FIG.  1 . 
     FIG. 7 is a sectional view of the composite intake manifold assembly taken along line  7 — 7  of FIG.  6 . 
     FIG. 8 is a sectional view of the composite intake manifold assembly taken along line  8 — 8  of FIG.  6 . 
     FIG. 9 is a sectional view of the composite intake manifold assembly taken along line  9 — 9  of FIG.  6 . 
     FIG. 10 is a sectional view of the composite intake manifold assembly taken along line  10 — 10  of FIG.  6 . 
     FIG. 11 is a sectional view of the composite intake manifold assembly taken along line  11 — 11  of FIG.  6 . 
     FIG. 12 is a sectional view of the composite intake manifold assembly taken along line  12 — 12  of FIG.  6 . 
     FIG. 13 is a sectional view of the composite intake manifold assembly taken along line  13 — 13  of FIG.  6 . 
     FIG. 14 is a perspective view of an alternate embodiment of a partial inner shell which can be used in connection with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, there is illustrated in FIG. 1 a perspective view of a first embodiment of a composite air intake manifold assembly, indicated generally at  10 , in accordance with the present invention. The composite intake manifold assembly  10  shown in this embodiment is for use with a V-8 engine and includes a cover  12 , an upper half shell  14 , a one piece “full” inner shell or insert  16 , and a lower half shell  18 . As will be discussed below, the cover  12 , the upper half shell  14 , the one piece inner shell  16 , and the lower half shell  18  are joined together and sealed by a suitable process to produce the composite intake manifold assembly  10  in accordance with this invention. 
     Preferably, the process used to form the composite intake manifold assembly  10  of this invention is a welding process. More preferably, the welding process is a linear vibration welding process. However, other suitable welding process which are operative to “heat” the surfaces causing the melting and/or fusing together of the surfaces can be used if desired. Preferably, such welding processes cause heat at the associated surfaces to create friction therebetween and cause the surfaces to be joined together by melting and/or fusing. However, welding processes which do not create friction between the adjacent surfaces but which are still effective to create heat between the surfaces to join them together can be used. For example, suitable friction welding processes can include an ultrasonic welding process, a non-linear vibration welding process, and a hot plate welding process; suitable non-friction welding processes can include laser or infrared processes. In addition, as will be discussed below, different processes can be used for the joining of the components of the air intake manifold assembly  10  of this invention and the sealing of the components thereof. 
     Preferably, the cover  12 , the upper half shell  14 , the one piece inner shell  16 , and the lower half shell  18  of the composite intake manifold assembly  10  are all formed of the same material. Such a suitable material is a glass reinforced nylon. Alternatively, other suitable materials can be used and/or the materials of one or more of the cover  12 , the upper half shell  14 , the one piece inner shell  16 , and the lower half shell  18  can be different than the others. For example, other suitable materials can include unreinforced nylon and mineral reinforced nylon. Although the composite intake manifold assembly  10  illustrated and described herein is for use with a V-8 engine application, it will be appreciated that the invention can be used in conjunction with other types of engines. For example, the composite manifold assembly can be used in connection with an inline 4 cylinder engine (I-4), an inline 6 cylinder engine (I-6), and a V-6 cylinder engine. 
     As shown in FIG. 1, the cover  12  is a molded cover formed from a suitable is plastic material and includes a plurality of integrally molded in place vacuum taps (two of such taps illustrated in this embodiment at reference numbers  20  and  22 ). The cover  12  includes an outer peripheral edge  26  which defines an underside insertion or connecting flange  28 . Alternatively, the shape and/or the structure of the cover  12  can be other than illustrated depending upon the particular structure of the associated intake manifold assembly. The upper half shell  14  is a one piece molded half shell formed from a polymer material and includes a plenum or air intake chamber  30  and eight generally tubular shaped upper runners  32 ,  34 ,  36 ,  38 ,  40 ,  42 ,  44 , and  46 . Each of the runners  32 ,  34 ,  36 ,  38 ,  40 ,  42 ,  44 , and  46  includes a respective generally arch like inner surface  32 A,  34 A,  36 A,  38 A,  40 A,  42 A,  44 A, and  46 A, shown in FIG. 7, which defines an associated upper runner inner wall surface. 
     The upper half shell  14  includes a flange  48  having an opening  50  formed therein. The flange  48  is adapted to be connected to a throttle body (not shown) and the opening  50  functions as an air intake port to supply atmospheric air to the plenum  30 . The upper half shell  14  further includes an opening  52  which generally corresponds to the profile of the flange  28  of the cover  12 . The opening  52  defines a receiving flange  54  which is adapted to receive the insertion flange  28  of the cover  12  in a mating relationship therewith. Alternatively, the cover  12  could be eliminated and the upper half shell  14  could include an integrally molded cover (not shown). 
     The upper half shell  14  includes an outer peripheral edge  60  which defines a pair of opposed side flanges  56  and  58  and a pair of opposed end flanges  66  and  68 , best shown in FIG.  2 . The side flange  56  includes five mounting holes  70 , and the side flange  58  includes five mounting holes  72 . As will be discussed below, the mounting holes  70  and  72  are adapted to receive a suitable fastener (not shown) for securing the composite intake manifold assembly  10  to a flange (not shown) of the cylinder heads (not shown) of an engine (not shown) thereby connecting each of the runners of the manifold assembly to a respective inlet of each cylinder head. 
     The upper half shell  14  further includes a pair of side flanges  62  and  64  which are spaced inwardly relative to side flanges  56  and  58 , respectively. As will be discussed below, the side flanges  62  and  64  and the end flanges  66  and  68  cooperate to define a continuous welding periphery or border around the edge  60  of the upper half shell  14  (partially shown in FIG. 2A by dashed line W 1 ), for securing the upper half shell  14  to the one piece inner shell  16 . The upper half shell  14  further includes a plurality of receiving flanges F 1 -F 9 , shown in FIG.  2 . As will be discussed below, each of the receiving flanges F 1 -F 9  of the upper half shell  14  are adapted to receive an associated one of a plurality of insertion flanges provided on the one piece inner shell  16 . 
     In the illustrated embodiment, the upper half shell  14  further includes an integrally molded in place mounting bracket  80  (shown in FIGS.  6  and  12 ), and an integrally molded in place threaded sensor fitting connection  82  (shown in FIGS.  6  and  12 ). The mounting bracket  80  is adapted to secure throttle and cruise control cables (not shown) thereto. In the illustrated embodiment, the sensor fitting connection  82  is adapted to secure a charge air temperature (CAT) fitting with a turn and lock retaining feature. 
     The upper half shell  14  further includes eight air inlet ports  32 B,  34 B,  36 B,  38 B,  40 B,  42 B,  44 B, and  46 B. As will be discussed below, the air inlet ports  32 B,  34 B,  36 B,  38 B,  40 B,  42 B,  44 B, and  46 B are adapted to be connected to an associated inlet port of each cylinder head of the engine to supply the air from a respective one of the runners to an associated cylinder. The lower half shell  18  is a one piece molded half shell formed from a polymer material and includes eight generally tubular shaped upper runners  132 ,  134 ,  136 ,  138 ,  140 ,  142 ,  144 , and  146 . Each of the runners  132 ,  134 ,  136 ,  138 ,  140 ,  142 ,  144 , and  146  includes a respective arch like inner surface  132 A,  134 A,  136 A,  138 A,  140 A,  142 A,  144 A, and  146 A, shown in FIG. 7, which define an associated lower runner inner wall surface. 
     The lower half shell  18  includes an outer peripheral edge  160  which defines a pair of opposed side flanges  162  and  164  and a pair of opposed end flanges  166  and  168 . As will be discussed below, the side flanges  162  and  164  and the end flanges  166  and  168  cooperate to define a continuous welding periphery or border around the edge  160  of the lower half shell  18  (partially shown in FIG. 3A by dashed line X 1 ), for securing the lower half shell  18  to the one piece inner shell  16 . As can be seen, in this embodiment the upper half shell welding periphery W 1  and the lower half shell welding periphery X 1  are generally the same. However, the welding peripheries W 1  and X 1  can be other than illustrated if desired. The lower half shell  18  further includes an opening  130  which is in fluid communication with the plenum  30  of the upper half shell  14 . The lower half shell  18  further includes a plurality of receiving flanges G 1 -G 9 , shown in FIG.  3 . As will be discussed below, each of the flanges G 1 -G 9  of the lower half shell  18  are adapted to receive a corresponding one of a plurality of insertion flanges provided on the one piece inner shell  16 . 
     In the illustrated embodiment, the one piece inner shell  16  is a one piece molded shell formed from a polymer material and includes eight generally tubular shaped runner centers  232 ,  234 ,  236 ,  238 ,  240 ,  242 ,  244 , and  246 . As will be discussed below, the one piece inner shell runner centers  232 ,  234 ,  236 ,  238 ,  240 ,  242 ,  244 , and  246  in combination with the respective upper half shell runner inner wall surfaces  32 A,  34 A,  36 A,  38 A,  40 A,  42 A,  44 A, and  46 A and lower half shell runner inner wall surfaces  32 A,  34 A,  36 A,  38 A,  40 A,  42 A,  44 A, and  46 A define eight runners R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  (only one of such runners R 4  is illustrated in detail in FIG.  13 ), of the composite intake manifold assembly  10 . While only runner R 4  is illustrated in detail in FIG. 13, it is understood that the other runners R 1 -R 3  and R 5 -R 8  are essentially the same as runner R 4 . FIG. 8 is a partial sectional view showing runner R 1 , and FIG. 9 is a partial sectional view showing runner R 2  in detail. 
     The one piece inner shell  16  includes an outer peripheral edge  260  which defines a pair of opposed side flanges  262  and  264  and a pair of opposed end flanges  266  and  268 . The side flange  262  includes an upper side flange surface  262 A and a lower side flange surface  262 B, and the side flange  264  includes an upper side flange surface  264 A and a lower side flange surface  264 B. The end flange  266  includes an upper end flange surface  266 A and a lower end flange surface  267 B, and the end flange  268  includes an upper end flange surface  268 A and a lower end flange surface  268 B. 
     As will be discussed below, the upper side flange surfaces  262 A and  264 A and the upper end flange surfaces  266 A and  268 A cooperate to define a continuous welding periphery or border around an upper edge  260  of the one piece inner shell  16  (partially shown in FIGS. 3A and 4A by dashed line Y 1 ), for securing the one piece inner shell  16  to the upper half shell  114 ; and the lower side flange surfaces  262 B and  264 B and the lower end flange surfaces  266 B and  268 B cooperate to define a continuous welding periphery or border (not shown but similar to welding periphery shown by dashed line Y 1  described above) around a lower edge  260  of the one piece inner shell  16  for securing the one piece inner shell  16  to the lower half shell  18 . The one piece inner shell  16  further includes a main air collection chamber  230  which is operative to supply air from the plenum  30  to each of the runners R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8  of the intake manifold assembly  10 . In FIG. 10, the main air collection chamber  230  is shown supplying air to runners R 7  and R 8 . 
     Each of the runner centers  232 ,  234 ,  236 ,  238 ,  240 ,  242 ,  244 , and  246  includes a respective air intake port, indicated generally at  232 A,  234 A,  236 A,  238 A,  240 A,  242 A,  244 A, and  246 A, and a respective air outlet port, indicated generally at  232 B,  234 B,  236 B,  238 B,  240 B,  242 B,  244 B, and  246 B. The air intake ports  232 A,  234 A,  236 A,  238 A,  240 A,  242 A,  244 A, and  246 A are in fluid communication with the main air collection chamber  230 , and the air outlet ports  232 B,  234 B,  236 B,  238 B,  240 B,  242 B,  244 B, and  246 B are in fluid communication with an associated one of the air inlet ports  32 B,  34 B,  36 B,  38 B,  40 B,  42 B,  44 B, and  46 B of the upper half shell  14 . 
     The one piece inner shell  16  further includes a plurality of longitudinal insertion flanges F 1 ′-F 9 ′ provided on the upper portion thereof, and a plurality of longitudinal insertion flanges G 1 ′-G 9 ′ provided on the lower portion thereof. As best shown in FIGS. 4 and 5, the insertion flange F 3 ′ is defined by a portion of an insertion flange F 3 A′ of runner center  234  and a portion of an insertion flange F 3 B′ of runner center  236 . Insertion flanges F 5 ′, F 7 ′, G 3 ′, G 5 ′, and G 7 ′ have a similar construction to that of insertion flange F 3 ′. As will be discussed below, the insertion flanges F 1 ′-F 9 ′ and G 1 ′-G 9 ′ of the one piece inner shell  16  are adapted to be received into respective receiving flanges F 1 -F 9  and G 1 -G 9  of the upper half shell  14  and the lower half shell  18 , shown in FIG.  7  and in FIG.  12 . Alternatively, insertion flanges could be provided on the upper half shell  14  and the lower half shell  18  and receiving flanges adapted to receive such insertion flanges could be provided on the one piece inner shell  16 . 
     To assemble the components together to produce the intake manifold assembly  10 , the following process occurs. First, the cover  12  is positioned adjacent the upper half shell  14  by aligning the underside insertion flange  28  of the cover  12  with the receiving flange  54  of the upper half shell  14 . Next, a linear vibration welding process is preferably used to permanently secure the cover  12  to the upper half shell  14 . The weld used to secure the cover  12  to the upper half shell  14  is both a structural weld and a sealing flange. 
     Following this, the one piece inner shell  16  is properly positioned and aligned within the upper half shell  14  so that the side and end flanges  62 ,  64 ,  66 , and  68  of the upper half shell  14  are disposed adjacent the respective upper side and end flanges  262 A,  264 A,  266 A, and  268 A of the one piece inner shell  16 . In addition, the receiving flanges F 1 -F 9  of the upper half shell  14  and the associated insertion flanges F 1 ′-F 9 ′ of the one piece inner shell  16  are disposed in a mating and/or interlocking relationship therewith. 
     With the one piece inner shell  16  maintained in this position, preferably a vibration welding process is used to permanently secure the one piece inner shell  16  to the upper half shell  14 . In particular, the upper half shell  14  and the one piece inner shell  16  are welded together along their associated weld planes or joints W 1  and Y 1  to provide a structural weld to join the components together and also to provide a “sealing” connection or weld between the components (welds W 1  and Y 1  partially shown in FIG.  2 A and FIGS. 4A and 5A, respectively). In addition, the upper half shell  14  and the one piece inner shell  16  are welded along the F 2 -F 9  and F 2 ′-F 9 ′, respectively, to provide a sealing weld therebetween (only welds W 2  and W 3  of the upper half shell  14  at flanges F 2  and F 3  illustrated in FIG. 2A, and only welds Y 2  and Y 3  of the insert illustrated in FIGS.  4 A and  5 A). As a result, each of the individual runners R 1 -R 8  in the upper half shell portion of the intake manifold assembly  10  is completely sealed off from fluid communication with an associated adjacent runner. While in this embodiment a weld is not illustrated at flanges F 1  and F 1 ′, a weld can be provided along these flanges or along any other flanges depending upon the particular structure of the associated upper half shell  14  and one piece inner shell  16 . 
     Next, the lower half shell  18  is properly positioned and aligned within the partially assembled air intake manifold assembly so that the side and end flanges  162 ,  164 ,  166 , and  168  of the lower half shell  18  are disposed adjacent the respective lower side and end flanges  262 B,  264 B,  266 B, and  268 B of the one piece inner shell  16 . In addition, the receiving flanges G 1 -G 9  of the lower half shell  18  and the associated insertion G 1 ′ G 9 ′ of the one piece inner shell  16  are disposed in a mating and/or interlocking relationship therewith. 
     With the lower half shell  18  maintained in this position, preferably a vibration welding process is used to permanently secure the insert lower half shell  18  to the partly assembled air intake manifold assembly and to produce the air intake manifold assembly  10  of this invention. In particular, the lower half shell  18  and the one piece inner shell  16  are welded together along their associated weld planes or joints to provide a structural weld (only weld X 1  of the lower half shell  18  illustrated in FIG. 3A) to join the components together and also to provide a “sealing” weld between the components. In addition, the lower half shell  18  and the one piece inner shell  16  are welded or otherwise connected along the flanges G 1 -G 9  and G 1 ′-G 9 ′, respectively, to provide a sealing weld therebetween (only welds X 2 , X 3  and X 4  of the lower half shell  18  at flanges G 1 , G 2  and G 3  illustrated in FIG. 2A, no welds shown for one piece inner shell  16  but are similar to those welds Y 2  and Y 3  of the one piece inner shell  16  illustrated in FIGS.  4 A and  5 A). As a result, each of the individual runners R 1 -R 8  in the lower half shell portion of the intake manifold assembly  10  is completely sealed off from fluid communication with an associated adjacent runner. Alternatively, if it is not desired to seal off a runner from an associated adjacent runner, or if a different type of insert is used (as will be discussed below in connection with FIG.  14 ), or if no insert is used at all, only the “structural” weld along the associated flanges  62 ,  64 ,  66 ,  68  and  162 ,  164 ,  166 , and  168  of the upper half shell  14  and the lower half shell  18  may be needed. Also, the structure of the receiving flanges F 1 -F 9  and G 1 -G 9  of the upper half shell  14  and the lower half shell  18 , respectively, and/or the structure of the insertion flanges F 1 ′-F 9 ′ and G 1 ′-G 9 ′ of the one piece inner shell  16  can be other than illustrated if desired. If however it is desired to prevent air leakage from adjacent runners, the structure of such flanges should be such that they are in relatively close proximity with one another to allow them to be joined together to provide a seal therebetween. 
     As discussed above, FIG. 13 illustrates runner R 4  in detail. As shown therein, runner R 4  functions to supply air from main chamber  230 , to air inlet port  138 A, in the direction of the arrows, to air outlet port  138 B, and to air inlet port  38 B. Also, since the runner center  234  of the one piece inner shell  16  is sealed along all adjacent surfaces of the upper half shell  14  and the lower half shell  18 , all the air entering runner R 4  from port  138 A is supplied to port  38 B without any air leakage to the adjacent runners R 3  and R 5 . Thus, a “360 degree” wrap weld joint is created in runner R 4 , as well as the other runners R 1 -R 3  and R 5 -R 8 . The term 360 degree wrap weld joint as used herein refers to the fact that the associated runner is completely sealed around its entire arch shaped path from an adjacent runner, the path being defined from the air inlet port of the runner to the associated air outlet port thereof in a generally full circular path (i.e., a 360 degree like path). As a result, there is no air leakage from one runner to an adjacent runner, and the air supplied to each associated cylinder head is maintained uniform. 
     FIG. 14 illustrates an alternate embodiment of a partial inner shell or insert, indicated generally at  316 , which can be used in place of the one piece full inner shell  16 . The partial inner shell  316  includes flanges  318 ,  320 ,  322 ,  324 , and  326 . The flanges  318 ,  320 ,  322 ,  324 , and  326  are provided with respective openings  318 A,  320 A,  322 A,  324 A, and  326 A. The openings  318 A,  320 A, and  322 A are operative to enable the partial inner shell  316  to be joined to the associated upper half shell  14  or lower half shell  18  by an appropriate method, such as for example, by heat staking. The openings  324 A and  326 A are operative to enable additional inserts (not shown) to be connected to the partial inner shell  316 . The number of partial inner shells  316  which are used is dependent upon the particular vehicle application. 
     One advantage of the air intake manifold assembly  10  illustrated in FIGS. 1-13 is that the runners R 1 -R 8  are completely sealed off from fluid communication with each adjacent runner to prevent air leakage from one runner to an adjacent runner. As a result of this, the air supplied to each associated cylinder head from the air intake manifold assembly  10  of this invention is maintained at a desired generally constant flow rate. Another advantage of the air intake manifold assembly  10  illustrated in FIGS. 1-13 is that the one piece inner shell  16  can be formed for a variety of different vehicle engine applications. As a result of this, various runner lengths and plenum volumes can be attained by only modifying the one piece inner shell  16  of the present invention. Yet another advantage of this invention is that the one piece inner shell  16  allows a generally arch shaped runner with a greater than 180 degrees wrap. Still a further advantage of the air intake manifold assembly  10  of this invention is that a generally “straight” weld is used to connect the side flanges  62  and  162  and  64  and  164  of associated upper half shell  14  and the lower half shell  18 . This straight weld can be used with the one piece full inner shell  16  illustrated in FIGS. 1,  4 ,  4 A,  5 ,  5 A, and  7 - 13 , the insert  316  illustrated in FIG. 14, or with no inner shell at all. In addition, a straight weld could be used to connect the side flanges  62  and  162  and  64  and  164 , and a separate structural and/or sealing weld could be used with the inner shell or inner shells. In either of the above structures, as a result of this generally straight weld, the associated “burst pressure strength” of the air intake manifold assembly  10  is increased. Thus, the air intake manifold assembly  10  of this invention can eliminate the need of providing a costly blow off safety valve. Still a further advantage of the air intake manifold assembly  10  of this invention is that the upper half shell  14  includes an integrally molded in place mounting bracket  80 , sensor fitting connection  82 , and vacuum taps  20  and  22 . As a result of this, the costs associated with the brass fitting typically used for the connection and taps can be eliminated. 
     In accordance with the provisions of the patents statues, the principle and mode of operation of this invention have been described and illustrated in its preferred embodiments. However, it must be understood that the invention may be practiced otherwise than as specifically explained and illustrated without departing from the scope or spirit of the attached claims.