Patent Publication Number: US-10767613-B2

Title: Fuel injector with locating pins, internal combustion engine using the same, and method

Description:
TECHNICAL FIELD OF INVENTION 
     The present invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, and more particularly to such a fuel injector with locating pins which orient the fuel injector relative to the combustion chamber and prevent rotation of the fuel injector. 
     BACKGROUND OF INVENTION 
     Fuel systems in modern internal combustion engines commonly inject fuel directly into a combustion chamber of the internal combustion engine. The fuel injector includes a nozzle body which is inserted into a fuel injector receiving bore of the internal combustion engine along a nozzle body axis. In order to achieve optimal combustion of the fuel provided by the fuel injector, thereby maximizing fuel efficiency and minimizing harmful exhaust emissions, it is known to orient the fuel injector relative to the combustion chamber in such a way that is most conducive of achieving optimal combustion. One known way to orient the fuel injector is illustrated in U.S. Pat. No. 7,886,717 to Rettig et al. where the fuel injector is provided with a fixation device which is received within a recess of the internal combustion engine which limits the extent to which the nozzle body is able to rotate within the fuel injector receiving bore. The fixation device of Rettig et al. is a feature which is formed in a plastic injection molding process with a valve housing of the fuel injector. In arrangements such as Rettig et al., the fixation device is designed to provide a clearance fit with the recess in order to accommodate for manufacturing variations when forming the fixation device. This clearance fit allows for some rotation of the fuel injector about the nozzle body axis, thereby resulting in variations in how the spray from the fuel injector is introduced into the combustion chamber. As a result, the spray from the fuel injector may not be optimally placed in the combustion chamber which may lead to reduced fuel economy and increased harmful exhaust emissions. 
     What is needed is a fuel injector which minimizes or eliminates one or more of the shortcomings as set forth above. 
     SUMMARY OF THE INVENTION 
     Briefly described, a fuel injector is provided by the present invention for injecting fuel into a combustion chamber of an internal combustion engine. The fuel injector includes a nozzle body configured to be inserted into a fuel injector receiving bore of the internal combustion engine along a nozzle body axis; a valve housing held in fixed relationship to the nozzle body; and a first locating pin and a second locating pin each extending from the valve housing, the first locating pin extending from a first locating pin fixed end which is fixed to the valve housing to a first locating pin free end and the second locating pin extending from a second locating pin fixed end which is fixed to the valve housing to a second locating pin free end, the first locating pin and the second locating pin collectively being configured to be inserted into a locating bore which elastically deforms the first locating pin and the second locating pin, thereby preventing rotational movement of the fuel injector about the nozzle body axis. An internal combustion engine including the fuel injector is also provided by the present invention. A method of assembling the fuel injector to the internal combustion engine is also provided by the present invention. The method includes inserting the nozzle body into the fuel injector receiving bore; inserting the first locating pin and the second locating pin into the locating bore; and elastically deforming the first locating pin and the second locating pin while the first locating pin and the second locating pin are being inserted into the locating bore such that the first locating pin and the second locating pin radially orient the nozzle body in the fuel injector receiving bore and thereby preventing rotation movement of the fuel injector about the nozzle body axis. 
     The fuel injector, internal combustion engine, and method of assembling the fuel injector to the internal combustion engine included herein provide for positive orientation, by forcing the locating pins collectively to be centered in the locating bore, of the fuel injector relative to the combustion chamber of the internal combustion engine which is necessary to achieve desired combustion of the fuel, thereby maximizing fuel efficiency, minimizing harmful exhaust emissions, and minimizing variation in fuel injector to combustion chamber placement. 
     Further features and advantages of the invention will appear more clearly on a reading of the following detailed description of the preferred embodiment of the invention, which is given by way of non-limiting example only and with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       This invention will be further described with reference to the accompanying drawings in which: 
         FIG. 1  is an elevation view of a fuel injector in accordance with the present invention installed in an internal combustion engine; 
         FIG. 2  is a schematic view of the fuel injector of  FIG. 1 ; 
         FIG. 3  is an isometric view of the fuel injector of  FIG. 1 ; 
         FIG. 4  is an end view of a first locating pin and a second locating pin of the fuel injector of  FIG. 1 ; 
         FIG. 5  is an elevation view of the first locating pin and the second locating pin of  FIG. 4 ; 
         FIG. 6  is an isometric view of another fuel injector in accordance with the present invention; 
         FIG. 7  is an end view of a first locating pin and a second locating pin of the fuel injector of  FIG. 6 ; and 
         FIG. 8  is an elevation view of the first locating pin and the second locating pin of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF INVENTION 
     In accordance with a preferred embodiment of this invention and referring initially to  FIGS. 1 and 2 , a fuel injector  10  is illustrated installed in an internal combustion engine  12  where fuel injector  10  is provided for injecting fuel into a combustion chamber  14  of internal combustion engine  12  where the fuel is combusted therein as is well known to those of ordinary skill in the art. The fuel which is injected by fuel injector  10  into combustion chamber  14  may be any one of numerous fuels commonly used by internal combustion engines, but may preferably be a liquid fuel which may be, by way of non-limiting example only, gasoline, alcohol, ethanol, diesel fuel, biodiesel, and the like or blends of one or more thereof or may alternatively be a gaseous fuel such as compressed natural gas (CNG) or propane. 
     Fuel injector  10  generally includes a nozzle body  16  which is configured to be inserted into a fuel injector receiving bore  18  of internal combustion engine  12  along a nozzle body axis  20  such that a nozzle tip  24  communicates with combustion chamber  14  and includes one or more nozzle openings  26  therein from which fuel is selectively discharged from fuel injector  10  into combustion chamber  14 . The discharge of fuel from nozzle openings  26  is controlled by a valve needle  28  located within nozzle body  16  where valve needle  28  is selectively seated with a valve seat  30  (shown in solid lines in the enlarged portion of  FIG. 2 ) to stop discharge of fuel through nozzle openings  26  and is selectively unseated with valve seat  30  (shown in phantom lines in the enlarged portion of  FIG. 2 ) to discharge fuel from fuel injector  10  into combustion chamber  14 . Movement of valve needle  28  is controlled by an actuator  32 , illustrated herein as a solenoid actuator. As embodied herein, actuator  32  includes a wire winding  34 , a pole piece  36  which is stationary, an armature  38  which is moveable with valve needle  28 , and a return spring  40  which urges valve needle  28  in a direction to be seated with valve seat  30 . When wire winding  34  is energized with an electric current, armature  38  is magnetically attracted to pole piece  36 , thereby unseating valve needle  28  from valve seat  30 . Conversely, when the electric current to wire winding  34  is stopped, the magnetic attraction between armature  38  and pole piece  36  is stopped, thereby allowing return spring  40  to move valve needle  28  to be seated with valve seat  30 . While actuator  32  has been illustrated herein as a solenoid actuator, it should be understood that actuator  32  may take other forms, which may be, by way of non-limiting example only, a piezoelectric actuator. Furthermore, while actuator  32  has been illustrated as directly actuating valve needle  28 , it should be understood that actuator  32  may be indirect acting such that the actuator may be used to control fuel pressure in a control chamber such that the fuel pressure in the control chamber affects the position of valve needle  28 . 
     Fuel injector  10  also includes a valve housing  42  which is distal from nozzle tip  24 . Valve housing  42  is held in fixed relationship to nozzle body  16  such that relative movement between valve housing  42  and nozzle body  16  is prevented. Valve housing  42  is made of a thermoplastic material which is preferably formed in a plastic injection molding process where liquefied plastic is injected into a mold (not shown) where the liquefied plastic is allowed to solidify before being removed from the mold. Valve housing  42  includes a valve housing first portion  42   a  which is used to fix valve housing  42  relative to nozzle body  16 , a valve housing electrical connector  42   b  which includes electrical terminals  44  therein for providing electrical connection to actuator  32 , and a valve housing intermediate portion  42   c  which joins valve housing first portion  42   a  to valve housing electrical connector  42   b . Valve housing electrical connector  42   b  is configured to mate with a complementary electrical connector (not shown) which makes electrical connection with electrical terminals  44  to selectively supply electric current thereto. 
     In order to achieve desired combustion which produces low levels of emissions, nozzle tip  24  must be properly oriented with respect to combustion chamber  14  about nozzle body axis  20 , thereby allowing fuel emitted from nozzle openings  26  to be introduced into combustion chamber  14  in such a way as to promote efficient combustion. It is important to note that the desired orientation of nozzle tip  24  with respect to combustion chamber  14  is dependent on may factors which may be, by way of non-limiting example only, the location of fuel injector receiving bore  18  relative to combustion chamber  14  and the location of a spark plug (not shown) which may be used to ignite the fuel. Furthermore, a practitioner of ordinary skill in the art would be able to determine the desired orientation of nozzle tip  24  with respect to combustion chamber  14 , for example, through modeling or empirical testing. Fuel injector  10  includes a first locating pin  46  extending from valve housing  42  and a second locating pin  47  also extending from valve housing  42 . First locating pin  46  and second locating pin  47  are configured to be collectively inserted into a locating bore  48  in order to ensure proper orientation of nozzle tip  24  with respect to combustion chamber  14  about nozzle body axis  20  such that first locating pin  46  and second locating pin  47  collectively prevent rotational movement of fuel injector  10  about nozzle body axis  20  through elastic deformation of first locating pin  46  and second locating pin  47 . Locating bore  48  may be located in the same portion of internal combustion engine  12  within which fuel injector receiving bore  18  is located or may be located in another element which is otherwise maintained in a fixed position relative to combustion chamber  14 . First locating pin  46  and second locating pin  47  will be described in greater detail in the paragraphs that follow. 
     Now with addition reference to  FIGS. 3-5 , first locating pin  46  and second locating pin  47  each extend from valve housing  42 , and more particularly valve housing intermediate portion  42   c , such that first locating pin  46  and second locating pin  47  are collectively centered about a locating pin axis  50 . First locating pin  46  extends from a first locating pin fixed end  46   a  which is fixed to valve housing  42  to a first locating pin free end  46   b  which terminates first locating pin  46 , and similarly, second locating pin  47  extends from a second locating pin fixed end  47   a  which is fixed to valve housing  42  to a second locating pin free end  47   b  which terminates second locating pin  47 . Locating pin axis  50  is eccentric to nozzle body axis  20  and is also preferably parallel to nozzle body axis  20 . As shown in  FIG. 4 , first locating pin  46  and second locating pin  47  collectively have a width  52  in a first direction radially relative to nozzle body axis  20  and through locating pin axis  50 . First locating pin  46  and second locating pin  47  also collectively have a length  54  in a second direction which is perpendicular to width  52  and in a plane perpendicular to locating pin axis  50  such that length  54  is greater in magnitude than width  52 . A gap  56 , i.e. void space, is formed between first locating pin  46  and second locating pin  47  such that gap  56  extends from first locating pin free end  46   b  and second locating pin free end  47   b  to first locating pin fixed end  46   a  and second locating pin fixed end  47   a . As best illustrated in  FIG. 4 , an imaginary ray  58  extending radially from nozzle body axis  20  and through locating pin axis  50  passes through first locating pin  46 , second locating pin  47 , and gap  56 . As should be apparent from  FIG. 4 , by having length  54  greater in magnitude than width  52 , orientation of nozzle tip  24  is determined collectively by first locating pin  46  and second locating pin  47  at length  54  and rotation about nozzle body axis  20  is prevented collectively by first locating pin  46  and second locating pin  47 . 
     First locating pin  46  includes a first locating pin first surface  46   c  which is planar and a first locating pin second surface  46   d  which is planar and parallel to first locating pin first surface  46   c  such that imaginary ray  58  passes through first locating pin first surface  46   c  and first locating pin second surface  46   d . A first locating pin third surface  46   e  is planar and extends between first locating pin first surface  46   c  and first locating pin second surface  46   d  where first locating pin third surface  46   e  joins first locating pin first surface  46   c  and first locating pin second surface  46   d  with, for example, one or more radii, as shown. Opposing first locating pin third surface  46   e  is a first locating pin fourth surface  46   f  which is curvilinear and extends between first locating pin first surface  46   c  and first locating pin second surface  46   d . First locating pin fourth surface  46   f  includes a first locating pin contact pad  46   g  projecting outward therefrom at length  54  which is configured to engage locating bore  48  in order to elastically deform first locating pin  46  when first locating pin  46  is inserted into locating bore  48 . A first locating pin fifth surface  46   h  extends between first locating pin first surface  46   c  and first locating pin second surface  46   d  and also between first locating pin free end  46   b  and first locating pin fourth surface  46   f  such that first locating pin fifth surface  46   h  is planar and is tapered outward such that first locating pin fifth surface  46   h  causes the cross sectional area of first locating pin  46 , i.e. perpendicular to locating pin axis  50 , to increase in a direction from first locating pin free end  46   b  to first locating pin fourth surface  46   f . A first locating pin sixth surface  46   i  extends between first locating pin first surface  46   c  and first locating pin second surface  46   d  and also from first locating pin fourth surface  46   f  toward first locating pin fixed end  46   a  such that first locating pin sixth surface  46   i  is planar and is tapered inward such that first locating pin sixth surface  46   i  causes the cross sectional area of first locating pin  46 , i.e. perpendicular to locating pin axis  50 , to decrease in a direction from first locating pin fourth surface  46   f  toward first locating pin fixed end  46   a . The tapered nature of first locating pin fifth surface  46   h  and first locating pin sixth surface  46   i  allows for easy insertion of first locating pin  46  into locating bore  48 . 
     Second locating pin  47  includes a second locating pin first surface  47   c  which is planar and a second locating pin second surface  47   d  which is planar and parallel to second locating pin first surface  47   c  such that imaginary ray  58  extends through second locating pin first surface  47   c  and second locating pin second surface  47   d . A second locating pin third surface  47   e  is planar and extends between second locating pin first surface  47   c  and second locating pin second surface  47   d  where second locating pin third surface  47   e  joins second locating pin first surface  47   c  and second locating pin second surface  47   d  with, for example, one or more radii, as shown. Opposing second locating pin third surface  47   e  is a second locating pin fourth surface  47   f  which is curvilinear and extends between second locating pin first surface  47   c  and second locating pin second surface  47   d . Second locating pin fourth surface  47   f  includes a second locating pin contact pad  47   g  projecting outward therefrom at length  54  which is configured to engage locating bore  48  in order to elastically deform second locating pin  47  when second locating pin  47  is inserted into locating bore  48  and which is diametrically opposed to first locating pin contact pad  46   g . As used herein, “diametrically opposed” includes being exactly diametrically opposed, i.e. spaced 180° apart about locating pin axis  50 , and also includes deviations from being exactly diametrically opposed of up to 10° about locating pin axis  50 . A second locating pin fifth surface  47   h  extends between second locating pin first surface  47   c  and second locating pin second surface  47   d  and also between second locating pin free end  47   b  and second locating pin fourth surface  47   f  such that second locating pin fifth surface  47   h  is planar and is tapered outward such that second locating pin fifth surface  47   h  causes the cross sectional area of second locating pin  47 , i.e. perpendicular to locating pin axis  50 , to increase in a direction from second locating pin free end  47   b  to second locating pin fourth surface  47   f . A second locating pin sixth surface  47   i  extends between second locating pin first surface  47   c  and second locating pin second surface  47   d  and also from second locating pin fourth surface  47   f  toward second locating pin fixed end  47   a  such that second locating pin sixth surface  47   i  is planar and is tapered inward such that second locating pin sixth surface  47   i  causes the cross sectional area of second locating pin  47 , i.e. perpendicular to locating pin axis  50 , to decrease in a direction from second locating pin fourth surface  47   f  toward second locating pin fixed end  47   a . The tapered nature of second locating pin fifth surface  47   h  and second locating pin sixth surface  47   i  allows for easy insertion of second locating pin  47  into locating bore  48 . 
     First locating pin contact pad  46   g  and second locating pin contact pad  47   g  each extend around the periphery of a circumcircle  60  which circumscribes first locating pin contact pad  46   g  and second locating pin contact pad  47   g  for no more than 10° about locating pin axis  50 . Furthermore, a first distance  62  radially outward from a point on locating pin axis  50  to first locating pin contact pad  46   g  is no more than 10% greater than a second distance  64  radially outward from the point on locating pin axis  50  to first locating pin fourth surface  46   f . Similarly, a third distance  66  radially outward from a point on locating pin axis  50  to second locating pin contact pad  47   g  is no more than 10% greater than a fourth distance  68  radially outward from the point on locating pin axis  50  to second locating pin fourth surface  47   f.    
     In order to assemble fuel injector  10  to internal combustion engine  12 , nozzle body  16  is first aligned with, and inserted at least part way into, fuel injector receiving bore  18 . Next, first locating pin  46  and second locating pin  47  are aligned with locating bore  48  and first locating pin  46  and second locating pin  47  are inserted into locating bore  48  such that inserting first locating pin  46  causes first locating pin contact pad  46   g  and second locating pin contact pad  47   g  to engage the inner periphery of locating bore  48  and such that first locating pin  46  and second locating pin  47  elastically deform, thereby preventing rotation of fuel injector  10  about nozzle body axis  20 . The step of inserting first locating pin  46  and second locating pin  47  into locating bore  48  may also include inserting nozzle body  16  further into locating bore  48 . Since first locating pin  46  and second locating pin  47  are provide with gap  56  therebetween, first locating pin  46  and second locating  47  are able to be elastically deformed independent of each other. 
     In an alternative arrangement as shown in  FIGS. 6-8 , a fuel injector  110  is shown which is substantially the same as fuel injector  10  except that first locating pin  46  and second locating pin  47  have been substituted with a first locating pin  146  and a second locating pin  147 . Elements that are the same as fuel injector  10  will use the same reference number in the description of fuel injector  110  and only the differences of first locating pin  146  and second locating pin  147  pin will be described with the understanding that other features of fuel injector  110  fall under the same description previously provide with respect to fuel injector  10 . 
     First locating pin  146  and second locating pin  147  each extend from valve housing  42 . First locating pin  146  and second locating pin  147  are configured to be collectively inserted into locating bore  48  in order to ensure proper orientation of nozzle tip  24  with respect to combustion chamber  14  about nozzle body axis  20  such that first locating pin  146  and second locating pin  147  collectively prevent rotational movement of fuel injector  10  about nozzle body axis  20  through elastic deformation of first locating pin  146  and second locating pin  147 . First locating pin  146  and second locating pin  147  will be described in greater detail in the paragraphs that follow. 
     First locating pin  146  and second locating pin  147  each extend from valve housing  42 , and more particularly valve housing intermediate portion  42   c , such that first locating pin  146  and second locating pin  147  are collectively centered about locating pin axis  150 . First locating pin  146  extends from a first locating pin fixed end  146   a  which is fixed to valve housing  42  to a first locating pin free end  146   b  which terminates first locating pin  146 , and similarly, second locating pin  147  extends from a second locating pin fixed end  147   a  which is fixed to valve housing  42  to a second locating pin free end  147   b  which terminates second locating pin  147 . As shown in  FIG. 7 , first locating pin  146  and second locating pin  147  collectively have a width  152  in a first direction radially relative to nozzle body axis  20  and through locating pin axis  150 . First locating pin  146  and second locating pin  147  also collectively have a length  154  in a second direction which is perpendicular to width  152  and in a plane perpendicular to locating pin axis  150  such that length  154  is greater in magnitude than width  152 . A gap  156 , i.e. void space, is formed between first locating pin  146  and second locating pin  147  such that gap  156  extends from first locating pin free end  146   b  and second locating pin free end  147   b  to first locating pin fixed end  146   a  and second locating pin fixed end  147   a . As best illustrated in  FIG. 7 , an imaginary ray  158  extending radially from nozzle body axis  20  and through locating pin axis  150  passes through first locating pin  146 , second locating pin  147 , and gap  156 . As should be apparent from  FIG. 7 , by having length  154  greater in magnitude than width  152 , orientation of nozzle tip  24  is determined collectively by first locating pin  146  and second locating pin  147  at length  154  and rotation about nozzle body axis  20  is collectively prevented by first locating pin  146  and second locating pin  147 . 
     First locating pin  146  includes a first locating pin first surface  146   c  which is curvilinear and convex facing away from locating pin axis  150  and also includes a first locating pin second surface  146   d  which is curvilinear and concave facing toward locating pin axis  150 . A first locating pin third surface  146   e  is planar and extends between first locating pin first surface  146   c  and first locating pin second surface  146   d  where first locating pin third surface  146   e  joins first locating pin first surface  146   c  and first locating pin second surface  146   d  with, for example, one or more radii, as shown. A first locating pin fourth surface  146   f  is planar and extends between first locating pin first surface  146   c  and first locating pin second surface  146   d . First locating pin first surface  146   c  includes a first locating pin contact pad  146   g  projecting outward therefrom at length  154  which is configured to engage locating bore  48  in order to elastically deform first locating pin  146  when first locating pin  146  is inserted into locating bore  48 . As shown in the figures, first locating pin  146  is tapered from first locating pin contact pad  146   g  toward first locating pin free end  146   b , thereby causing the cross-sectional area of first locating pin  146  to decrease from first locating pin contact pad  146   g  toward first locating pin free end  146   b  and also thereby allowing for easy insertion of first locating pin  146  into locating bore  48 . 
     Second locating pin  147  includes a second locating pin first surface  147   c  which is curvilinear and convex facing away from locating pin axis  150  and also includes a second locating pin second surface  147   d  which is curvilinear and concave facing toward locating pin axis  150 . A second locating pin third surface  147   e  is planar and extends between second locating pin first surface  147   c  and second locating pin second surface  147   d  where second locating pin third surface  147   e  joins second locating pin first surface  147   c  and second locating pin second surface  147   d  with, for example, one or more radii, as shown. A second locating pin fourth surface  147   f  is planar and extends between second locating pin first surface  147   c  and second locating pin second surface  147   d . Second locating pin first surface  147   c  includes a second locating pin contact pad  147   g  projecting outward therefrom at length  154  which is configured to engage locating bore  48  in order to elastically deform second locating pin  147  when second locating pin  147  is inserted into locating bore  48  and which is diametrically opposed to first locating pin contact pad  146   g . As used herein, “diametrically opposed” includes being exactly diametrically opposed, i.e. spaced 180° apart about locating pin axis  150 , and also includes deviations from being exactly diametrically opposed of up to 10° about locating pin axis  150 . As shown in the figures, second locating pin  147  is tapered from second locating pin contact pad  147   g  toward second locating pin free end  147   b , thereby causing the cross-sectional area of second locating pin  147  to decrease from second locating pin contact pad  147   g  toward second locating pin free end  147   b  and also thereby allowing for easy insertion of second locating pin  147  into locating bore  48 . 
     First locating pin contact pad  146   g  and second locating pin contact pad  147   g  each extend around the periphery of a circumcircle  160  (shown as coincident with locating bore  48  in  FIG. 7 ) which circumscribes first locating pin contact pad  146   g  and second locating pin contact pad  147   g  for no more than 10° about locating pin axis  150 . Furthermore, a first distance  162  radially outward from a point on locating pin axis  150  to first locating pin contact pad  146   g  is no more than 10% greater than a second distance  164  radially outward from the point on locating pin axis  150  to first locating pin first surface  146   c . Similarly, a third distance  166  radially outward from a point on locating pin axis  150  to second locating pin contact pad  147   g  is no more than 10% greater than a fourth distance  168  radially outward from the point on locating pin axis  150  to second locating pin first surface  147   c.    
     In order to assemble fuel injector  110  to internal combustion engine  12 , nozzle body  16  is first aligned with, and inserted at least part way into, fuel injector receiving bore  18 . Next, first locating pin  146  and second locating pin  147  are aligned with locating bore  48  and first locating pin  146  and second locating pin  147  are inserted into locating bore  48  such that inserting first locating pin  146  and second locating pin  147  causes first locating pin contact pad  146   g  and second locating pin contact pad  147   g  to engage the inner periphery of locating bore  48  and such that first locating pin  146  and second locating pin  147  elastically deform, thereby preventing rotation of fuel injector  10  about nozzle body axis  20 . Due to first locating pin first surface  146   c  and first locating pin second surface  146   d  being curvilinear, elastic deformation of first locating pin  146  includes twisting in a plane that is perpendicular to locating pin axis  150 . Similarly, due to second locating pin first surface  147   c  and second locating pin second surface  147   d  being curvilinear, elastic deformation of first locating pin  146  includes twisting in a plane that is perpendicular to locating pin axis  150 . The step of inserting first locating pin  146  and second locating pin  147  into locating bore  48  may also include inserting nozzle body  16  further into locating bore  48 . Since first locating pin  146  and second locating pin  147  are provide with gap  156  therebetween, first locating pin  146  and second locating  147  are able to be elastically deformed independent of each other. 
     It should be noted that  FIG. 4  illustrates first locating pin  46  and second locating pin  47  in a free state, i.e. not elastically deformed, in order to illustrate the interference that first locating pin  46  and second locating pin  47  encounter with locating bore  48 . Conversely,  FIG. 7  illustrates first locating pin  146  and second locating pin  147  in an elastically deformed state in order to illustrate how first locating pin  146  and second locating pin  147  elastically deform to conform to locating bore  48 . However, it should now be understood that first locating pin  46  and second locating pin  47  elastically deform similar to the illustration of first locating pin  146  and second locating pin  147  when inserted into locating bore  48 . 
     While this invention has been described in terms of preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow.