Abstract:
The invention relates to an air intake for an engine ( 19 ) of a motor vehicle. In particular, the present invention concerns a detachable connection between an air collector module ( 10 ) and an intake duct module ( 11 ) of the air intake. The invention also concerns a method for installing the air intake to the engine ( 19 ) of the motor vehicle. A preferred embodiment of the air intake comprises a detachable connection comprising at least one releasable connection arrangement ( 17 ) and at least one interlock arrangement ( 18 ). The at least one releasable connection arrangement ( 17 ) comprises a releasable connector ( 25 ) inserted through the air collector module ( 10 ) and arranged to secure the air collector module ( 10 ) to the intake duct module ( 11 ). The at least one interlock arrangement ( 18 ) comprises a bracket ( 31 ) mounted on one of the air collector module ( 10 ) and the intake duct module ( 11 ), and an opposing piece ( 32 ) mounted on the other of the air collector module ( 10 ) and the intake duct module ( 11 ).

Description:
This application claims the benefit of Provisional Application No. 60/308,561, filed Jul. 31, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to an air intake for an engine of a motor vehicle. In particular, the present invention concerns a detachable connection between an air collector module and an intake duct module of the air intake. The invention also concerns a method for installing the air intake to the engine of the motor vehicle. 
     A known intake device is disclosed in European Patent No. 0 467 408 (corresponding to U.S. Pat. No. 5,144,918). This intake device includes an intake channel module and a collector module. The intake channel module consists of several intake ports, whereby the intake ports are connected on one side to an internal combustion engine and on the other side to the collector module. The connection between the collector module and the intake port module has a circular connecting surface which can be implemented either with a threaded connection or with a fixed connection. The intake port module must be made from a high-quality temperature-resistant material since the material is exposed to elevated temperatures in the area where the intake port module connects to the internal combustion engine. 
     Due to the circular shape of the connecting surf ace and the accessibility of the screws at the connecting surface, in order for a detachable connection of the intake device to be achieved, the intake port module must first be connected to the collector module before fastening it to the internal combustion engine. However, if the engine compartment is cramped, the intake device can only be fastened to the internal combustion engine under difficult conditions and/or cannot be connected at all. Moreover, the collector module and the intake port module are made from the same materials which causes greater expense. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to avoid at least the above-identified disadvantages of the prior art and thereby provide an air intake which is cost-effective and easily installed. This is achieved by way of the air intake of the present invention which comprises an air collector module and an intake duct module. A preferred embodiment of the air intake comprises a detachable connection comprising at least one releasable connection arrangement and at least one interlock arrangement. The at least one releasable connection arrangement comprises a releasable connector inserted through the air collector module and arranged to secure the air collector module to the intake duct module. The at least one interlock arrangement comprises a bracket mounted on one of the air collector module and the intake duct module, and an opposing piece mounted on the other of the air collector module and the intake duct module and in secure contact with the bracket. 
     As a result of the present invention, the air collector module can be connected to the intake duct module with a detachable connection which is cost-effective and easily installed in an engine compartment. 
     Since the material of the intake duct module is stronger than the material of the air collector module, the air collector module is provided with a strength increasing member which operates to substantially prevent the releasable connector from deforming the air collector module. In a preferred embodiment, the strength increasing member is a sleeve. By incorporating such a strength increasing member, which is preferably metallic, the air collector module will not undergo deformation, even under a maximum tightening force of the releasable connector, since any deformations will be overcome by the strength increasing member. 
     According to an advantageous further embodiment of the invention, the strength-increasing means is a bearing bushing which is arranged in a holding bracket of the air collector module. The bearing bushing is fitted into the air collector module which can be made from a material having a lower strength compared to the bearing bushing. It is also possible to coat the bearing by way of an injection coating procedure. The bearing bushing penetrates the air collector module in an area of the detachable connection such that a distribution of connecting forces occurs. In further advantageous embodiments, the bearing bushing penetrates completely into the air collector module and the intake duct module, whereby the bearing bushing has a contact surface with both of these components. A fastening means, for example, a screw or bolt, is passed through the bearing bushing for detachably connecting the air collector module and the intake duct module. 
     In a further preferred embodiment of the invention, the structure for increasing the strength comprises a material which has a higher strength than the material of the air collector module, and a lower strength than the material of the intake duct module. As an example, a structure for increasing the strength having such material characteristics can be an insert which is installed in a holder of the air collector module. The insert is interconnected with a bracket of the intake duct module such that connecting forces that occur in the detachable connection are conducted at least partially directly to the intake duct module which possesses the higher strength material. This prevents the material of the air collector module from beginning to yield in the area of the detachable connection, which could loosen the detachable connection. 
     In addition, the structure for increasing the strength can be, for example, a washer which contacts the air collector module and operates to provide a better distribution of force when tightening the detachable connection. Alternatively, the structure for increasing the strength is an area of the air collector module which has been subjected to a heat treated hardening process. 
     In the embodiment of the present invention incorporating the sleeve as the strength increasing member, the sleeve can be arranged to have at least two contact surfaces which are supported on the air collector module which is made from a material which is weaker than the material of the air collector module. In order to form these contact surfaces, the sleeve is shaped to (i) have rotational symmetry, (ii) be supported on one side by a releasable connector resting on the air collector module, and (iii) have a chamfered reduced shoulder. The reduction in dimension of the shoulder is necessary if the sleeve is to be pressed into the first component. For injection-coated sleeves, the shoulder can also be partially enlarged in its dimensions and reduced again at a defined distance. In this way, the sleeve cannot be accidentally removed from the air collector module during disassembly. 
     According to a further embodiment of the present invention, the air collector module and the intake duct module are connected to one another with a hinge-type connection. In this embodiment, two connecting devices are combined for achieving an optimum connection. The combination of the two connecting devices provides a very reliable connection while being simple to install. In particular, the hinge can be located to provide the most favorable installation. The air collector module is mounted on an intake duct module so that the air connector module can be swung out of the installation area during the installation of the intake duct module on the internal combustion engine. As a result, the fastening of the intake duct module on the internal combustion engine is simplified because of better accessibility. When the intake duct module is fastened on the internal combustion engine, the air collector module can then be fastened onto the intake duct module. The fastening of the air collector module to the intake duct module can be designed in such a way that the screws are arranged so that they are distributed uniformly in the connecting area. This results in stress relief for the hinge, which serves to simplify installation and position the air collector module on the intake duct module. 
     It is advantageous if the detachable connection mechanism is formed both by the interlock arrangement having the opposing piece and by the threaded connection mechanism having a strength increasing member, whereby the strength increasing member is mounted on a side opposite from the interlock arrangement. In this design, the interlock arrangement and the opposing piece, which can also be designed as a hinge, allow connecting forces to be absorbed. As a result of this design, during installation, only a partial area of the connection needs to be accessible, which is advantageous for narrow and partially obscured installation spaces. 
     Another embodiment of the present invention provides that a gasket is installed to achieve an adequate seal between the air collector module and the intake duct module, whereby the gasket is fixed on one of the two components. As a result of this design, the gasket cannot slip out during installation and cause leakage. For example, the gasket can be glued to fasten it to one of the components. In addition, the gasket can be at least partially installed in a recess provided on one of the components. 
     The method for installing an intake device according to the present invention can be divided into three important assembly steps. In the first assembly step, a strength-increasing structure is placed in the air collector module which is made from a material having a lower strength. In the second assembly step, the intake duct module is connected to the internal combustion engine. In the third assembly step, the air collector module is connected to the intake duct module. 
     Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a front view of an air intake incorporating a first preferred embodiment of the present invention; 
         FIG. 2  shows a cross-section of the air intake taken along line A—A of  FIG. 1 ; 
         FIG. 3  shows a cross-section of the air intake taken along line B—B of  FIG. 1 ; 
         FIG. 4  shows a front view of an air intake incorporating a second preferred embodiment of the present invention; 
         FIG. 5  shows a top view of the air intake of  FIG. 4 ; 
         FIG. 6  shows a cross-section of the second preferred embodiment of the air intake taken along line C—C of  FIG. 4 ; and 
         FIG. 7  shows a cross-section of the second preferred embodiment of the air intake taken along line D—D of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  illustrates a front view of an air intake incorporating a first preferred embodiment of the present invention. The air intake includes an air collector module  10  and an intake duct module  11 . Intake duct module  11  has several intake ducts  12  mounted in parallel to each other and a cylinder head flange  13 . Fastening holes  14  and recesses  15  are arranged in the area of the cylinder head flange  13  and are used to fasten the intake duct module  12  to a cylinder head  16  (as shown in  FIG. 2 ). The intake duct module  11  is detachably connected to the air collector module  11  through a connection mechanism. The connection mechanism comprises both releasable connections  17  and at least two interlock arrangements  18 , each of these connections  17 ,  18  being mounted on opposite sides of the air collector module  10 . Connections  17 ,  18  will be described in more detail in conjunction with  FIGS. 2 and 3 . 
       FIG. 2  shows a cross-section of the first preferred embodiment of the air intake taken along line A—A of  FIG. 1 . Line A—A runs through the threaded connection  17 . Similar components shown in  FIG. 1  are provided with identical reference numbers in  FIG. 2 . In  FIG. 2 , the air intake is connected to the cylinder head  16  of an internal combustion engine  19 . A connection between the cylinder head  16  and the cylinder head flange  13  is implemented by a head bolt  20  that is connected tightly to the cylinder head  16  and is hooked into a recess  15  as shown in  FIG. 1 . In order that the intake duct module  11 , which consists of cast aluminum, does not loosen from the cylinder head  16 , hex screws  21  are inserted through the fastening holes  14  and screwed together with the cylinder head  16 . 
     The air collector module  10  comprises two half-shells  22  that are welded together in a sealed fashioned. The sealed half-shells  22  are made from a plastic, e.g. polyamide. In an area of contact between the half-shells  22 , a circumference bead  23  is arranged. The two half-shells  22  surround a collector chamber  24  from which air reaches the individual intake ducts  12 . 
     At least one releasable connection  17  is provided for fastening the air collector module  10  to the intake duct module  11 . Each releasable connection  17  includes a releasable connector, such as a screw  25  or a clip. In an alternative embodiment, the screw  25  is surrounded by a sleeve  26  which operates as a strength increasing member to increase the strength of the air collector module  10 . It is especially advantageous to implement a strength increasing member when the air collector module  10  is made from a material which is not as strong as the material of the intake duct module  11 . For example, when the air collector module  10  is made from a plastic and the intake duct module  11  is made from a metal. The sleeve  26  can be arranged to be in contact with a washer  27 . The screw  25  penetrates the sleeve  26 , whereby it is screwed with its thread  28  extending out of sleeve  26  into the intake duct module  11 . In order to achieve optimum force distribution in the air collector module  10 , the sleeve  26  comprises a collar  29  and a shoulder  30 , and is made from metal. The collar  29  is supported on washer  27 , which lies on the upper half-shell  22 . The shoulder  30  rests on the lower half-shell  22  and thus conducts part of the connecting forces into the lower half-shell  22 . The end of the sleeve  26  rests directly on the intake duct module  11 . In this way, even with a maximum tightening force, the screw  25  can only deform the sleeve  26  without deforming the air collector module  10 . Since plastic begins to yield with continuous pressure, the connection would loosen over time and become unsealed if the sleeve were to be made from plastic. 
     In alternative embodiments of the air intake of the present invention, the strength increasing member is an area of the air collector module  10  which has been subjected to a heat treated hardening process. This hardened area of the air collector module  10  operates to reduce deformations of the air collector module  10  due to the tightening force exerted by the releasable connector, i.e. screw  25 . In further preferred embodiments, the strength increasing member is a washer which contacts the air collector module  10  and operates to distribute the tightening force exerted by the releasable connector on the air collector module  10 . 
       FIG. 3  shows a cross-section of the first preferred embodiment of the air intake taken along line B—B of  FIG. 1 . Similar components shown in  FIGS. 1 and 2  are provided with identical reference numbers in  FIG. 3 . This cross-section illustrates an interlock arrangement  18 , which is formed on one side by a bracket  31  mounted on the intake duct module  11  and on the other side by an opposing piece  32  mounted on the air collector module  10 . Alternatively, it is contemplated that the bracket  31  could be mounted on the air collector module  10 , and the opposing piece  32  could be mounted on the intake duct module  11 . The opposing piece  32  is formed by an insert  34  placed in an insert holder  33 . The insert  34  is pressed into the insert holder  33  such that it cannot fall out during assembly. In a preferred embodiment, the insert  34  is made from a metal that is somewhat softer than the intake duct module  11  but is harder than the air collector module  10 . The insert  34  has two opposing contact surfaces  35 , which contact the bracket  31 . 
       FIG. 4  shows a front view of a second preferred embodiment of the air intake of the present invention. Similar components shown in  FIG. 1  are provided with identical reference numbers in  FIG. 4 . This air intake has five intake ducts  12  that are mounted in parallel to each other. Threaded connections  17  and two hinge connections  36  are provided for connecting the air collector module  10  to the intake duct module  11 . The hinge connections  36  are shown in more detail in  FIGS. 6 and 7  as discussed below. 
       FIG. 5  shows a top view of the air intake of  FIG. 4 . Similar components shown in  FIG. 4  are provided with identical reference numbers in  FIG. 5 . The air collector module  10  has an air inlet pipe  37  through which air can enter into the collector chamber  24 . A flange  38  is mounted on the air inlet pipe  37  through which the air collector module  10  can be connected to adjacent air-carrying lines. The air contained in collector chamber  24  is then guided through the intake ducts  12  of the internal combustion engine  19 . 
       FIG. 6  shows a cross-section of the second preferred embodiment of the air intake taken along line C—C of  FIG. 4 . Similar components shown in  FIG. 3  are provided with identical reference numbers in  FIG. 6 . The hinge connection  36  is formed on one side by the air collector module  10  and on the other side by the intake duct module  11 . A first holding bracket  39  having three ribs  40  is formed on the air collector module  10  and a bearing bushing  41  made of metal is pressed into the first holding bracket  39 . A second holding bracket  42 , as shown in  FIG. 7 , is formed on the intake duct module  11 . A bolt  43  is passed through the second holding bracket  42  and the bearing bushing  41 . The bolt  43  operates to connect the air collector module  10  to the intake duct module  11 . 
       FIG. 7  shows a cross-section of the second preferred embodiment of the connection mechanism taken along line D—D of  FIG. 6 . Similar components shown in  FIG. 6  are provided with identical reference numbers in  FIG. 7 . As shown in  FIG. 7 , the second holding bracket  42  is designed to have two extending bolt supporting portions, such that a single bolt supporting portion of the first holding bracket  39  is arranged between two sides of the bolt supporting portions of the second holding bracket  42 . The bolt  43  penetrates through these portions of the holding brackets  39 ,  42  such that a head  44  contacts one side of a bolt supporting portion of the second holding bracket  42 . The side of bolt  43  opposite the head  44  is secured against loosening with any type of removable securing mechanism, such as a circlip  45 . The hinge connection  36  can be joined and/or separated whenever desired. However, normally a single installation procedure is performed. 
     A method for installing an air intake according to the invention can be divided into three assembly steps. In the first assembly step, the sleeve  26  or any strength-increasing structure is formed or inserted into the air collector module  10 . As previously discussed, the sleeve  26  or strength-increasing structure is made from a material having a higher strength relative to the air collector module  10 . In the second assembly step, the intake duct module  11  is connected to the internal combustion engine  19 . In the third assembly step, the air collector module  10  is connected to the intake duct module  11 . 
     Regarding the first assembly step, different methods can be used to install the strength-increasing structure  26  into the first component  10 . One option includes pressing the strength-increasing structure  26  into the air collector module  10 . In this method, the air collector module  10  comprises a material made with a relatively low strength, e.g., a thermoplastic like PA or PP. Since the strength-increasing structure  26  is made from a material having a greater strength, the material of the air collector module  10  is somewhat deformed when the strength-increasing structure  26  is pressed therein. Due to the press-fit, the strength-increasing structure  26  is fixed in the air collector module  10  and cannot fall out during at least installation or removal. 
     Another possibility for the installation of the strength-increasing structure  26  into the first component  10  comprises surrounding the strength-increasing structure  26  with material during the formation of the air collector module  10 . If, for example, the air collector module  10  is made from a thermoplastic, the strength-increasing structure  26  can be placed in the injection molding machine and then be injection-coated with plastic. In this process, the strength-increasing structure  26  can be provided with cutouts into which the material flows during the formation of the air collector module  10 . After hardening, the material produces a form-fit connection. 
     During the second assembly step, the intake duct module  11  is fastened to the internal combustion engine  19 , whereby the air collector module  10  is not yet fastened to the intake duct module  11 . If space for the installation is limited, the intake duct module  11  is screwed onto the cylinder head  16  of the internal combustion engine  19  with a cylinder head flange  13 . Since the air collector module  10  has not yet been connected to the intake duct module  11 , the air collector module  10  does not interfere with the installation of the intake duct module  11 . In this manner, an installer has easier access to the cylinder head flange  13  during the fastening of the intake duct module  11  to the cylinder head  16 . 
     During the third assembly step, the air collector module  10  is connected to the intake duct module  11 . Since the intake duct module  11  is already fastened to the cylinder head  16 , the installer does not have to be concerned with this connecting point, which at this time in the installation process is often times inaccessible. As a result of the method of the present invention, the inaccessibility of this connection point does not have a negative influence on the function of the device or its assembly since the intake duct module  11  generally has a long service life and therefore, is only attached to the internal combustion engine  19  once, and remains connected to the internal combustion engine  19  for its entire service life. If for some reason the intake duct module  11  has to be replaced, the air collector module  10  can be removed from the intake duct module  11  using the detachable connection mechanism of the present invention, whereby the connection between the cylinder head  16  and the intake duct module  11  becomes accessible again. 
     The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.