Patent Publication Number: US-9835120-B2

Title: Integral purge ejector tee arrangement in a turbocompressor

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. application Ser. No. 14/742,008, filed Jun. 17, 2015, which claims benefit of U.S. Provisional Application Ser. No. 62/014,386, filed on Jun. 19, 2014. The disclosures of the above applications are incorporated herein by reference in their entirety. 
    
    
     FIELD 
     The present application relates generally to an evaporative fuel emissions system for an engine and, more particularly, to an integral purge ejector tee arrangement in a turbocompressor. 
     BACKGROUND 
     Modern internal combustion engines typically generate hydrocarbon emissions by evaporative means and, as a result, vehicle fuel vapor emissions to the atmosphere are regulated. For the purpose of preventing fuel vapor from escaping to the atmosphere, an evaporative emissions (EVAP) system is typically implemented to store and subsequently dispose of fuel vapor emissions. The EVAP system is typically designed to collect vapors produced inside an engine&#39;s fuel system and then send them through an engine&#39;s intake manifold into its combustion chamber to get burned as part of the aggregate fuel-air charge. When pressure inside the vehicle&#39;s fuel tank reaches a predetermined level as a result of evaporation, the EVAP system transfers the vapor to a purge canister. Subsequently, when engine operating conditions are conducive, a purge valve opens and vacuum from the intake manifold draws the vapor into the engine&#39;s combustion chamber. Thereafter, the purge canister is regenerated with newly formed fuel vapor, and the cycle can continue. 
     In addition to the fuel vapor recovery function, an EVAP system is often required to perform a leak-detection function. To that end, a known analog leak-detection scheme employs an evaporative system integrity monitor (ESIM) switch which stays on if the system is properly sealed, and toggles off when a system leak is detected. When the ESIM switch is toggled off, an engine control unit (ECU) detects the change and alerts an operator of the vehicle with a malfunction indicator. 
     In view of the above, the inventors have recognized a need for an apparatus and methodology that permits an EVAP system to accomplish its prescribed fuel evaporative emissions purge and leak detection functions in forced induction applications while reducing leak paths in the EVAP system that are potentially undetectable. 
     SUMMARY 
     In accordance with an example aspect of the invention, a turbocompressor associated with a fuel vapor emissions system that is coupled to an intake manifold of an engine is provided. The turbocompressor includes a boost purge ejector tee integrated into the turbocompressor associated with the engine. In one exemplary implementation, the boost purge ejector tee includes a first passage formed into a housing of the turbocompressor along a common axis from a first direction, the first passage including an outlet in communication with an inlet area of the turbocompressor. A second passage is formed into the housing along the common axis from a second direction, the second passage intersecting a high pressure internal outlet area of the housing to form a boost air inlet in communication with the outlet area and being fluidly coupled to the first passage, the first and second passages of the housing defining a first flow path from the internal outlet area to the turbocompressor inlet. An inlet port is associated with the housing and intersects the first passage, the housing defining a second flow path from the inlet port to the outlet, and the second flow path intersecting the first flow path upstream of the outlet. A nozzle is positioned in the second passage such that an outlet of the nozzle is proximate the intersection of the first flow path with the second flow path. During a boost operation mode, the second passage is adapted to receive boost air flow, which flows through the nozzle along the first flow path thereby creating a vacuum and drawing purge through the inlet port. 
     In one exemplary implementation, the first and second passages are machined into the housing and the second passage defines the nozzle such that the nozzle is integral with the housing. In this implementation, the nozzle is formed during the machining of the second passage into the housing along the common axis. 
     In one exemplary implementation, the second passage is formed such that the nozzle defines an internal terminal end of the second passage opposite the boost air inlet and is in communication with the first passage. A terminal end of the nozzle can form the communication with the first passage. 
     In one exemplary implementation, the first passage is machined along the common axis from and through an internal wall of the inlet area of the turbocompressor housing without passing through any exterior wall of the housing. 
     In accordance with another example aspect of the invention, a method of manufacturing a turbocompressor associated with a fuel vapor emissions system that is coupled to an intake manifold of an engine is provided. In one exemplary implementation, the method includes providing a turbocompressor housing having an air inlet area, a high pressure internal air outlet area, and an inlet port associated with the housing; machining a first passage into the turbocompressor housing along a common axis from a first direction, the first passage including an outlet in communication with the air inlet of the turbocompressor; and machining a second passage into the housing along the common axis from a second direction, the second passage intersecting the high pressure internal outlet area of the housing to form a boost air inlet in communication with the outlet area and being fluidly coupled to the first passage, the first and second passages of the housing defining a first flow path from the internal outlet area to the air inlet area. The inlet port defines a second flow path from the inlet port to the outlet, the second flow path intersecting the first flow path upstream of the outlet. The second passage defines a nozzle in the first flow path such that an outlet of the nozzle is proximate the intersection of the first flow path with the second flow path. During a boost operation mode, the second passage is adapted to receive boost air flow, which flows through the nozzle along the first flow path thereby creating a vacuum and drawing purge through the inlet port. 
     Further areas of applicability of the teachings of the present disclosure will become apparent from the detailed description, claims and the drawings provided hereinafter, wherein like reference numerals refer to like features throughout the several views of the drawings. It should be understood that the detailed description, including disclosed embodiments and drawings referenced therein, are merely exemplary in nature intended for purposes of illustration only and are not intended to limit the scope of the present disclosure, its application or uses. Thus, variations that do not depart from the gist of the present disclosure are intended to be within the scope of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an EVAP system of a typical internal combustion engine with forced induction; 
         FIG. 2  is a schematic diagram of an EVAP system having an exemplary integral purge ejector tee arrangement for an internal combustion engine with forced induction according to the principles of the present disclosure; 
         FIG. 3  is a perspective view of an exemplary turbocompressor with an exemplary integral purge ejector tee arrangement associated therewith according to the principles of the present disclosure; 
         FIG. 4  is another perspective view of the exemplary turbocompressor with the exemplary integral purge ejector tee arrangement associated therewith according to the principles of the present disclosure; 
         FIG. 5  is a side view of the turbocompressor with the exemplary integral purge ejector tee arrangement associated therewith according to the principles of the present disclosure; 
         FIG. 6  is a sectional view of the turbocompressor with the exemplary integral purge ejector tee arrangement along line  6 - 6  of  FIG. 5  according to the principles of the present disclosure; 
         FIG. 7  is an enlarged view of area  7  of  FIG. 6  according to the principles of the present disclosure; 
         FIG. 8  is a perspective view of another exemplary turbocompressor with an integral purge ejector tee arrangement according to the principles of the present disclosure; 
         FIG. 9  is a side view of the exemplary turbocompressor shown in  FIG. 8  according to the principles of the present disclosure; 
         FIG. 10  is a cross-sectional view of the exemplary turbocompressor of  FIG. 8  taken along line  10 - 10  according to the principles of the present disclosure; 
         FIG. 11  is a cross-sectional view of yet another exemplary turbocompressor with an integral purge ejector tee arrangement according to the principles of the present disclosure; and 
         FIG. 12  is a cross-sectional view of yet another exemplary turbocompressor with an integral purge ejector tee arrangement according to the principles of the present disclosure. 
     
    
    
     DESCRIPTION 
     The present disclosure relates generally to a purge ejector tee arrangement for an engine, such as an internal combustion engine, with forced induction. In one exemplary implementation, this purge ejector tee arrangement is associated with an EVAP system and facilitates the EVAP system performing its prescribed fuel evaporative emissions purge and leak detection functions in forced induction applications, while also cooperating with the EVAP system to ensure that various potential system leak points are detected or detectable with the leak detection function. 
     In accordance with various aspects of the present disclosure, the purge ejector tee arrangement is integrated into a turbocompressor. In one exemplary implementation, the purge ejector tee arrangement is integrated into a cover or housing of the turbocompressor. As will be discussed in greater detail below, such an integral purge ejector tee arrangement eliminates fluid flow lines and connections from the EVAP system, which reduces complexity and improves robustness of the EVAP system, including improved leak detection capability. 
     Referring now to the drawings, in which like reference numerals refer to like or similar features,  FIG. 1  denotes an example of an EVAP system  10  of a typical internal combustion engine with forced induction. EVAP system  10  includes a fuel tank  20  in fluid communication with a pressure sensor  24  and a fill neck  28 . A purge canister  34  is in fluid communication with fuel tank  20  for capturing fuel vapor from the fuel tank  20 . Purge canister  34  is additionally in fluid communication with a purge valve  38 , which releases the purge canister&#39;s fuel vapor contents to an intake manifold  44  via fluid line  48  in response to engine manifold vacuum. Purge canister  34  is also in fluid communication with an evaporative system integrity monitor (ESIM) switch  54 , which is configured to stay on if the EVAP system is operatively sealed in the presence of engine vacuum, and to toggle off if the EVAP system experiences a leak (loss of vacuum). ESIM switch  54  is in fluid communication with atmosphere via a filter  58 . A further discussion of exemplary ESIM switches and ESIMs can be found in commonly owned U.S. Pat. Nos. 6,823,850; 6,928,991; 7,047,950 and 7,216,636; the entire disclosure of which is incorporated herein by reference. 
     The purge valve  38  is also in fluid communication with a multi-port connection member  62  via a fluid line  66 . Multi-port connection member  62  is in fluid communication with an air box  72  and/or inlet line to a turbocharger  76  via a fluid line  80 . Multi-port connection member  62  is also in fluid communication with a turbocharger output line or air tube  84  via a fluid line  88 . The turbocharger output line  84  connects an output of turbocharger  76  to intake manifold  44 . Intake manifold  44  communicates vacuum generated by an engine&#39;s  92  reciprocating pistons  98 , or boost pressure supplied by the exhaust-driven turbocharger  76 , a crankshaft-driven supercharger (not shown), or any other pressurizing means, as is readily understood by those skilled in the art. 
     In a naturally aspirated mode, the purge valve  38  is controlled to allow flow therethrough, and purge (e.g., fuel vapor drawn from purge canister  34 ) flows to the intake manifold  44  in a flow path depicted by arrows A in  FIG. 1 . The fuel vapor is drawn from purge canister  34  by intake manifold vacuum and the drawn fuel vapor is transferred via intake manifold  44  to the engine&#39;s combustion chamber (not shown) to be burned with the main fuel-air charge. In a boost condition facilitated by turbocharger  76 , purge flows in the direction of arrows B through purge valve  38  into multi-port connection member  62  via fluid line  66  and into the turbocharger inlet via fluid line  80 . The high pressure airflow from turbocharger  76  flows through fluid line  88  and multi-port connection member  62 , thereby drawing purge into fluid line  66  in the manner discussed above. 
     In addition to the fuel vapor recovery function, the EVAP system is also required to perform a leak detection function. In this regard, pressure sensor  24  is associated with the fuel tank  20  for measuring a system pressure. The pressure at the pressure sensor  24  is monitored by a vehicle controller or the like (not specifically shown) during operation and the vehicle and/or EVAP system to sense feedback, as is readily understood by those skilled in the art. For example, when the EVAP system  10  is operating in a boost condition, if the fluid line  88  becomes disconnected or pinched, there will be a significant reduction in flow through multi-port connection member  62 . This would result in a significantly reduced draw or flow of purge through fluid line  66 . This reduction in purge flow will be sensed by pressure sensor  24  in the form of a lack of vacuum in fuel tank  20 . Similarly, if fluid line  66  is disconnected in the boost operating mode, purge flow cannot be drawn therethrough and thus there will also be a corresponding lack of vacuum detected at pressure sensor  24 . For example, the vacuum pressure would be lower than a predetermined threshold. 
     If fluid line  80  becomes disconnected, however, such a scenario could potentially remain undetected by the EVAP system  10  leak detection function. With fluid line  80  disconnected, ruptured, etc., purge in a boost mode of operation could potentially flow to the atmosphere instead of into the engine in the manner discussed above. A disconnection of line  80  could be undetected by the leak detection function of EVAP system  10  in the boost mode of operation because positive pressure airflow from the turbocharger  76  flowing through fluid line  88  will draw purge from canister  34  through fluid line  66  regardless of whether line  88  is connected or disconnected. As a result, pressure sensor  24  could detect vacuum pressure above the predetermined threshold due to the purge flow in boost even when fluid line  88  is disconnected. 
     Turning now to  FIGS. 2-7 , an exemplary EVAP system is shown and generally identified at reference numeral  100  in accordance with the principles of the present disclosure. EVAP system  100  includes an integral purge ejector tee arrangement  104  configured to provide improved leak detection functionality while also reducing cost and complexity by eliminating components from the EVAP system  100 . As will be discussed in greater detail below, in one exemplary implementation, the integral purge ejector tee arrangement  104  is integrated with or into a turbocompressor  106  thereby eliminating the connection lines  80  and  88  of EVAP system  10 . Thus EVAP system  100  provides a more robust system with fewer components and potential leak paths while also improving leak detection capabilities and reducing cost, as will be discussed in greater detail below. 
     In the exemplary schematic illustration of EVAP system  100  shown in  FIG. 2 , where like reference numerals refer to like components in the various figures, EVAP system  100  includes the integral purge ejector tee arrangement  104  associated with turbocompressor  106 . In one exemplary implementation, the integral purge ejector tee arrangement  104  includes a purge ejector tee system formed into and/or with a cover or housing  110  of the turbocompressor  106 . As briefly discussed above, this arrangement eliminates the fluid lines  80  and  88 , which eliminates multiple potential leak paths as well as eliminates a portion of the EVAP system  10  that is potentially not detectable in a leaking and/or disconnected condition. 
     With particular reference to  FIGS. 3-7 , the integral purge ejector tee arrangement  104  will now be discussed in greater detail. In the exemplary implementation illustrated, the integral purge ejector tee arrangement  104  includes permanent passages formed in housing  110  of turbocompressor  106  such that the passages are internal and cannot be disconnected. In this exemplary implementation, the integral purge ejector tee arrangement  104  includes first and second passages  118  and  114 , a third passage  126 , a nipple or other connection member or inlet port  122 , and an insert member  134 . The first and second passages  118 ,  114  connect an inlet side of the turbocompressor housing structure  110  to an outlet or discharge (compressed air) side in communication with an outlet of turbocompressor  106 . 
     As will be discussed in greater detail below, the inlet port  122  can be coupled or can integrally form the third passage  126  that intersects with the first passage  118 , and the insert member  134  is positioned in the first passage  118  at an end opposite the end in communication with the inlet side of the turbocompressor  106 . In one exemplary implementation, the inlet port  122  is directly connected to and in direct fluid communication with first passage  118 . In one exemplary implementation, the inlet port  122  is integrally formed with the housing  110 , such as through a casting process. In the exemplary implementation illustrated, the third passage  126  and thus inlet port  122  are positioned downstream of second passage  114  from a perspective of a flow of compressed or boost air from the outlet side to the inlet side of the turbocompressor  106 . As will be discussed in greater detail below, the inlet port  122  is coupled to the fluid line  66 . 
     The insert member  134  includes an orifice  138  and is positioned in first passage  118  such that the orifice is downstream of the second passage  114  but upstream of passage  126 , as will also be discussed below in greater detail. In one exemplary implementation, the orifice  138  forms a venturi nozzle. As will be discussed in greater detail below, the venturi nozzle creates a vacuum effect due to the increased velocity of the flow therethrough thereby drawing fluid through the inlet port  122  from fluid line  66  coupled thereto. 
     The insert member  134  includes a flow entrance  146  in fluid communication with the orifice/nozzle  138 . The insert member  134  is positioned in first passage  118  such that the flow entrance  146  is aligned with second passage  114  and an outlet  150  of the orifice  138  is positioned upstream or substantially upstream of an intersection  154  of passages  118  and  126 . In one exemplary implementation, the flow entrance  146  includes one or more radial passages  158  in fluid communication with venturi nozzle  138 . It will be appreciated that the features and operation of the insert member  134  could optionally be integrally formed in the housing structure  110 . In one exemplary implementation, the insert member  134  is positioned in or at least partially in the first passage  118  and the second passage  114  such that the one or more radial passages  158  are aligned with the second passage  114  and the nozzle  138  is positioned in and aligned with the first passage  118  downstream of the second passage  114 , as shown in  FIG. 7 . 
     In one exemplary implementation, the second passage  114  is a blind passage formed in the housing structure  110 , as shown in the various figures. In this exemplary implementation, the first passage  118  is formed as a through passage from an exterior  162  of the housing structure  110  to an inlet side of the turbocompressor  106 . Once the first passage  118  is formed in the exemplary manner discussed above, the insert member  134  may also provide the function of sealing off a portion  164  of first passage  118  between an intersection of passages  114  and  118  and the exterior  162  of housing structure  110 , as also shown in the various figures. Alternatively, a separate cap or closure member could be utilized to seal off the portion  164  of passage  118 . In one exemplary implementation, the inlet port  122  and the insert member  134  are threadably coupled to the turbocompressor housing  110 . 
     With particular reference to  FIG. 2  and continuing reference to  FIGS. 3-7 , operation of the EVAP system  100  will now be discussed in greater detail. As briefly mentioned above, EVAP system  100  includes the integral purge ejector tee arrangement  104 , which replaces/eliminates the external multi-port connection member  62  and fluid lines  80  and  88 . This integral purge ejector tee arrangement  104  thereby reduces complexity and improves robustness of the EVAP system  100 , including improved leak detection capability. 
     The EVAP system  100 , in the exemplary implementation illustrated, includes a controller  166 , the air box  72  coupled to an inlet  170  of turbocompressor  106 , and an outlet or discharge  174  in fluid communication with a charge air cooler and the intake manifold  44 . The fluid line  66  is coupled at one end  180  to fluid line  48  and at an opposite end  184  to third passage  126  via inlet port  122  of the integral purge ejector tee arrangement  104 . In one exemplary implementation, the fluid line  66  provides direct fluid communication between the purge inlet to the integral purge ejector tee arrangement  104  (e.g., passage  126 ) and the purge valve  38 . As discussed above, the exemplary EVAP system  100  that includes the exemplary integral ejector tee arrangement  104  eliminates the need for an external tee member  62  as well as fluid lines  80  and  88 . It will be appreciated, however, that other EVAP system configurations associated with forced induction engines can be utilized with the integral purge ejector tee arrangement  104 . 
     In operation, in a naturally aspirated mode, the purge valve  38  is selectively controlled to allow flow therethrough, and purge can flow to the intake manifold  44  in a flow path depicted by arrows A in  FIG. 2 . The purge is drawn from purge canister  34  by intake manifold vacuum and is transferred via intake manifold  44  to the engine&#39;s combustion chamber (not specifically shown) to be burned with the main fuel-air charge. In a boost mode of operation facilitated by turbocompressor  106 , high pressure or compressed air (boost air) flow from turbocompressor  106  having a higher pressure than manifold pressure flows from turbocompressor outlet  174  to the intake manifold  44  through air tube  84 . 
     In this boost mode of operation, air enters turbocompressor  106  via inlet  170  and is compressed and flows as compressed or boost air into turbocompressor volute area  194 , which is on the outlet or discharge side of turbocompressor  106 , as is readily appreciated by those skilled in the art. The outlet side housing compressed air, such as volute area  194 , is in direct fluid communication with second passage  114 , as shown in the various figures. The compressed or boost air from volute area  194  flows into second passage  114  via inlet  196  and into flow entrance  146  of insert member  134  along a first flow path C inside turbocompressor  106 , as shown in  FIG. 7 . 
     Once in insert member  134 , the boost air flows through orifice or venturi nozzle  138  and exits at a higher velocity through outlet  150 , which creates a low pressure or vacuum when flowing past intersection  154  to an outlet  198  of flow passage  118  along the first flow path C. This vacuum or low pressure draws purge along flow path B of fluid line  66  and through connection member or inlet port  122  along a second flow path D inside turbocompressor  106 . In particular, the vacuum created by the high speed boost air flow past intersection  154  draws purge through purge valve  38 , through fluid line  66  and directly into inlet port  122  along the second flow path D. The purge is drawn through inlet port  122  and exits the inlet port via outlet  202  and flows along flow path D into a portion of passage  118  downstream of outlet  202  and intersection  154 , where it mixes with the high speed boost air flowing toward outlet  198  of passage  118  along combined flow paths C and D, as also shown in  FIG. 7 . The combined boost air and purge then flows through and exits turbocompressor  106  at outlet  174 , where it then flows to the engine and is burned as part of the aggregate fuel-air charge. 
     Turning now to  FIGS. 8-10 , another example purge ejector tee arrangement is generally identified at  204  and may be utilized with EVAP system  100 . The purge ejector tee arrangement  204  is configured to provide improved leak detection functionality while also reducing cost and complexity by eliminating components from the EVAP system  100 . As will be discussed in greater detail below, in one exemplary implementation, the purge ejector tee arrangement  204  is integrated with or into a turbocompressor  206 , thereby eliminating the connection lines  80  and  88  of EVAP system  10 . Thus, the purge ejector tee arrangement  204  similarly provides the EVAP system  100  with a more robust system having fewer components and potential leak paths while also improving leak detection capabilities and reducing cost. 
     Moreover, as described herein in more detail, the purge ejector tee arrangement  204  includes integral fluid passages formed along a common axis. These integral fluid passages require minimal machining and/or forming through the housing of turbocompressor  206 , thereby reducing manufacturing complexity and reducing or eliminating plugs and/or other sealing operations. Accordingly, only two fluid passages are required to be machined or formed along the common axis. A first fluid passage is formed along the common axis through an interior wall defining the turbocompressor inlet without passing through any exterior walls of the turbocompressor housing. The first fluid passage intersects with a purge inlet passage. A second fluid passage is formed along the common axis from an exterior wall of the turbocompressor housing and intersects a high pressure area or volute of the turbocompressor to receive pressurized fluid therefrom. The second fluid passage includes an integrally formed nozzle (venturi) that communicates with the first fluid passage. As such, a separate nozzle is not required, and only a single machining axis (common axis) and single sealing plug are required. 
     In one exemplary implementation, the purge ejector tee arrangement  204  includes a purge ejector tee formed into a housing  210  of the turbocompressor  206 . As briefly discussed above, this arrangement eliminates the fluid lines  80  and  88 , which eliminate multiple potential leak paths as well as eliminate a portion of the EVAP system  10  that is potentially not detectable in a leaking and/or disconnected condition. 
     With particular reference to  FIG. 10 , the integral purge ejector tee arrangement  204  will now be discussed in greater detail. In the exemplary implementation illustrated, the integral purge ejector tee arrangement  204  includes permanent passages formed in a housing  210  of turbocompressor  206  such that the passages are internal and cannot be disconnected. In this exemplary implementation, the integral purge ejector tee arrangement  204  includes first and second passages  214  and  218 , a third passage  226 , a fitting or other connection member or inlet port  222 , and a single plug  224 . The first and second passages  214 ,  218  connect an inlet side of the turbocompressor housing structure  210  to an outlet or discharge (compressed air) side in communication with an outlet of turbocompressor  206 . 
     As will be discussed in greater detail below, the inlet port  222  can be coupled within or can integrally formed with the third passage  226  that intersects at  254  with the first passage  214 . In one example implementation, third passage  226  can be machined or drilled into housing  210 . The plug  224  is positioned in the second passage  218  at an end opposite the end in communication with the inlet side of the turbocompressor  206 . In one exemplary implementation, the inlet port  222  is directly connected to and in direct fluid communication with first passage  214 . In one exemplary implementation, the inlet port  222  is a machined fitting threadably secured at least partially within the third passage  226 . In the exemplary implementation illustrated, the third passage  226  and thus inlet port  222  are positioned downstream of second passage  218  from a perspective of a flow of compressed or boost air from the outlet side to the inlet side of the turbocompressor  206 . The inlet port  222  is coupled to the fluid line  66  ( FIG. 2 ). 
     In one exemplary implementation, the second passage  218  includes an orifice  238  that forms a venturi nozzle. The venturi nozzle creates a vacuum effect due to the increased velocity of the flow therethrough thereby drawing fluid through the inlet port  222  from fluid line  66  coupled thereto. In this exemplary implementation, the orifice/nozzle is integrally formed in/with the second passage such that an additional or extra machining operation is not required to form the nozzle. In this implementation, the nozzle is formed at an internal end of the second passage and a terminal end of the nozzle communicates with and connects the second passage  218  with the first passage  214 . 
     The second passage  218  includes a boost air inlet or flow entrance  246  in fluid communication between the orifice/nozzle  238  and an internal outlet area or compressor volute  294 . In this way, the second passage  218  intersects the volute  294  such that a separate passage is not required to fluidly connect the volute  294  and the second passage  218 . In one example implementation, flow entrance  246  may be formed during casting of housing  210 . The plug  224  is positioned in second passage  218  such that air flow from the flow entrance  246  is directed through an outlet  250  of the orifice  238  that is positioned upstream or substantially upstream of the intersection  254  of passages  214  and  226 . 
     In one exemplary implementation, the first and second passages  214 ,  218  are formed along a common axis ‘X’ to intersect with both the third passage  226  and the volute  294 , thereby reducing manufacturing complexity, obviating the need for a separate nozzle, and only requiring a single plug seal  224 . 
     Accordingly, in one example implementation, the first passage  214  is formed by machining through an internal wall  268  of an inlet  270  of the housing structure  210  by drilling along common axis ‘X’ from a first direction D 1 . In this exemplary implementation, the second passage  218  is formed by machining through an external or exterior wall  262  of the housing structure  210  along common axis ‘X’ from an opposite second direction D 2  toward an inlet side of the turbocompressor  206 . Once the second passage  218  is formed in the exemplary manner discussed above, the plug  224  may be inserted to seal off a portion  264  of second passage  218  between an intersection of passage  218  and volute  294  and the exterior  262  of housing structure  210 , as also shown in the various figures. In one exemplary implementation, the inlet port  222  and the plug  224  are threadably coupled to the turbocompressor housing  210 . 
     It should be noted that the EVAP system  100  with turbocompressor  206  operates in a manner similar to the system with turbocompressor  106 , as described herein. However, turbocompressor  206  only requires a simple two-step machining operation along a common axis ‘X’ to form the first passage  214  and the second passage  218 , which advantageously and respectively intersect with third passage  226  and volute  294  without requiring additional passages. The third inlet passage  226  may extend along an axis perpendicular to or substantially perpendicular to axis ‘X’. Accordingly, similar to that mentioned above, EVAP system  100  includes the integral purge ejector tee arrangement  204 , which replaces/eliminates the external multi-port connection member  62  and fluid lines  80  and  88 . This integral purge ejector tee arrangement  204  thereby reduces complexity and improves robustness of the EVAP system  100 , including improved leak detection capability. It will be appreciated, however, that other EVAP system configurations associated with forced induction engines can be utilized with the integral purge ejector tee arrangement  204 . 
     In a similar operation to turbocompressor  106 , the boost or high pressure flow C created by venturi nozzle  238  draws purge along low pressure flow path B of fluid line  66  and through connection member or inlet port  222  along a second flow path D inside turbocompressor  206 . In particular, the vacuum created by the high speed boost air flow past intersection  254  draws purge through purge valve  38 , through fluid line  66  and directly into inlet port  222  along the second flow path D. The purge is drawn through inlet port  222  and exits the inlet port via outlet  302  and flows along flow path D into a portion of passage  214  downstream of outlet  302  and intersection  254 , where it mixes with the high speed boost air flowing toward outlet  298  of passage  214  along combined flow paths C and D, as shown in  FIG. 10 . The combined boost air and purge then flows through and exits turbocompressor  206  at an outlet  274 , where it then flows to the engine and is burned as part of the aggregate fuel-air charge. 
       FIG. 11  illustrates another turbocompressor  306  and integral purge ejector tee arrangement  304  similar to turbocompressor  206  except first and second passages  314  and  318  are formed along the same common axis ‘X’ from the same location and in the same direction D 1 . In particular, passages  314  and  318  are machined through an internal wall  368  of an inlet  370  of the turbocompressor  306 . The second passage  318  has a smaller diameter than the first passage  314  and functions as the venturi nozzle. As such, the smaller second passage  318  may be formed or machined along axis ‘X’, and the larger first passage  314  may be machined along axis ‘X’ thereafter. Alternatively, the larger first passage  314  is formed along axis ‘X’ first and the second passage  318  is formed along axis ‘X’ thereafter. 
       FIG. 12  illustrates another turbocompressor  406  and integral purge ejector tee arrangement  404  similar to turbocompressor  306  except an insert  434  may be disposed in a necked down portion  436  between first and second passages  414  and  418  that are formed along the same axis ‘X’ from the same location (internal wall  468  of inlet  470 ) and direction D 1 . The insert  434  includes an orifice  438  configured as the venturi nozzle. 
     As such, the turbocompressors described herein and illustrated in  FIGS. 1-12  integrate a purge port into the turbocompressor cover using bleed air from the turbocompressor to provide vacuum ejector tee motive force to draw purge vapor into the engine when intake manifold vacuum is unavailable. Such turbocompressors may include fully machined passages and eliminate the need for a separate ejector tee and orifice. The machined passages are formed along a common axis from at least an interior wall of the turbocompressor inlet, thereby reducing manufacturing complexity, lowering costs, and reducing required parts compared to typical systems. 
     It should be understood that the mixing and matching of features, elements, methodologies and/or functions between various examples may be expressly contemplated herein so that one skilled in the art would appreciate from the present teachings that features, elements and/or functions of one example may be incorporated into another example as appropriate, unless described otherwise above.