Patent Publication Number: US-2018038274-A1

Title: Accessory mounting structure for engine

Description:
TECHNICAL FIELD 
     The present invention relates to an accessory mounting structure for an engine in an automobile or a like vehicle. More specifically, the present invention relates to an accessory mounting structure for an engine provided with a fuel pump configured to feed fuel to an injector. 
     BACKGROUND ART 
     In an automobile or a like vehicle, there is a transversely mounted engine, which is mounted in an engine room of a vehicle front portion in such a manner that the cylinder array direction is aligned with the vehicle width direction. The engine is mounted in an engine room in such a manner that a surface of an engine body on the intake side including a cylinder block faces the vehicle front side, and a surface of the engine body on the exhaust side faces the vehicle rear side. According to this configuration, it is possible to avoid lowering of an exhaust temperature due to traveling air, and to activate an exhaust purification device in an early stage and to maintain activation of the exhaust purification device. 
     In this case, in an engine configured to directly inject fuel to a combustion chamber such as a diesel engine or a direct injection engine (a cylinder injection engine), a high fuel pressure is required. This may increase the drive load of a fuel pump configured to feed fuel to an injector. In order to chain-drive a fuel pump by a crankshaft while avoiding a high temperature condition, the fuel pump is disposed on a side surface of an engine body on the intake side, in other words, on a side surface of an engine body on the vehicle front side. This may require a measure for protecting a fuel pump from a collision object from the vehicle front side at vehicle collusion (from the front side). 
     Regarding this point, Patent Literature 1 discloses disposing a fuel pump on a side surface of an end portion of an engine on the vehicle front side, and disposing a cover plate for protecting a vehicle from collision in such a manner that the cover plate covers a surface of the fuel pump on the vehicle front side. According to this configuration, it is possible to protect the fuel pump by the cover plate at vehicle collision from the front side. 
     As described above, in a transversely mounted engine configured such that a fuel pump is disposed on a side surface of an engine body on the vehicle front side and on an end portion of the engine body on the rear side (on the output side of a crankshaft with respect to a transmission in the cylinder array direction), it is necessary to provide a measure for protecting the fuel pump at vehicle collision from the front side. 
     In this case, if a dedicated protection member is additionally provided as disclosed in Patent Literature 1, not only the space for an engine room may be narrowed, but also the weight and the cost of an engine may increase. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Japanese Unexamined Patent Publication No. 2007-16716 
     SUMMARY OF INVENTION 
     The present invention relates to an accessory mounting structure for an engine provided with a fuel pump configured to feed fuel to an injector. An object of the present invention is to provide an accessory mounting structure for an engine, which enables to protect a fuel pump from a collision object at vehicle collision. 
     The present invention is directed to an accessory mounting structure for an engine including an engine body in which a plurality of cylinders are arranged in a row, and a transmission disposed on an end of the engine body in the cylinder array direction and to which output of the engine is transmitted via a crankshaft of the engine body. When an output side of the crankshaft with respect to the transmission in the cylinder array direction is defined as a rear side, and a side of the crankshaft opposite to the output side is defined as a front side, a fuel pump configured to feed fuel to an injector, and a starter configured to rotate the crankshaft at an engine start time are disposed on a rear end portion of an intake manifold mounting surface of the engine body. The starter projects outwardly with respect to the fuel pump in an engine width direction orthogonal to the cylinder array direction when the engine is viewed from the cylinder array direction. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic plan view of an engine according to an embodiment of the present invention; 
         FIG. 2  is a left side view of the engine in a state that a chain cover and a transmission are removed; 
         FIG. 3  is a front view of a body of the engine; 
         FIG. 4  is a left side view of the engine in a state that the chain cover and the transmission are removed; 
         FIG. 5  is a schematic front view of a rear end portion of the engine body; 
         FIG. 6  is a left side view of a cylinder block of the engine; 
         FIG. 7  is a schematic and partially longitudinal sectional view of the rear end portion of the engine body; 
         FIG. 8  is a perspective view of the engine when viewed from the front right side of the cylinder block; 
         FIG. 9  is an expanded view of the rear end portion of the engine body; 
         FIG. 10  is a left side view of a lower portion of the rear end portion of the engine body (in a state that an oil pan is removed); and 
         FIG. 11  is a perspective view of the engine when viewed from the front left side. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     In the following, an embodiment of the present invention is described based on the drawings. 
     As illustrated in  FIG. 1  and  FIG. 2 , an engine  1  according to the embodiment is an in-line 4-cylinder diesel engine (provided with a first cylinder #1, a second cylinder #2, a third cylinder #3, and a fourth cylinder #4), which is transversely mounted in an engine room  100  of a vehicle front portion in such a manner that the cylinder array direction is aligned with the vehicle width direction (an FF-vehicle). Although not illustrated, the engine  1  has a well-known structure, in which pistons, injectors (fuel injection valves), intake ports, exhaust ports, intake valves, and exhaust valves are provided on the outside or the inside of the cylinders. 
     As illustrated in  FIG. 1 , the engine  1  includes an engine body  10 , in which the first to fourth cylinders #1 to #4 are arranged in a row. As illustrated in  FIG. 3  and  FIG. 4 , the engine body  10  includes a head cover  11 , a cylinder head  12 , a cylinder block  13 , a lower block  14 , and an oil pan  15  in this order from the upper side. These members define the external appearance of the engine body  10 . A transmission  30  is engaged with an end portion of the engine body  10  on the rear side via a chain cover  20  (see  FIG. 1 ). Output of the engine  1  is transmitted to the transmission  30  via a crankshaft  2  of the engine body  10 . 
     Note that in the description of the embodiment, the output side of the crankshaft  2  with respect to the transmission  30  in the cylinder array direction, in other words, the output side (the transmission side) of the engine body  10  is referred to as a rear side of the engine body  10 ; and the side opposite to the rear side of the engine body  10  is referred to a front side of the engine body  10 . Further, an end portion (in other words, an end portion on the rear side) of the engine body  10  on the rear side of the engine body  10  is referred to as a rear end portion of the engine body  10 , and an end portion (in other words, an end portion on the front side) of the engine body  10  on the front side of the engine body  10  is referred to as a front end portion of the engine body  10 . Note that the term “front” in the drawings indicates a front side in the vehicle front-rear direction. 
     In  FIG. 4 , a circle illustrated by a chain line indicates an outer configuration (e.g. a pitch circle) of a flywheel  31  to be described later. 
     As illustrated in  FIG. 5 , the chain cover  20  is engaged over the cylinder head  12 , the cylinder block  13 , and the lower block  14 ; and the transmission  30  is engaged over the cylinder block  13  and the lower block  14 . An intake manifold  40  is connected to a surface of the engine body  10  on the vehicle front side, and an exhaust manifold  50  is connected to a surface of the engine body  10  on the vehicle rear side (see  FIG. 1 ). As described above, in an FF-vehicle, by disposing an intake system on the vehicle front side, and an exhaust system on the vehicle rear side, it is possible to avoid lowering of an exhaust temperature due to traveling air, and to activate an exhaust purification device (not illustrated) provided in the exhaust system in an early stage and to maintain activation of the exhaust purification device. 
     A front-side accessory drive device  60  configured to belt-drive a plurality of accessories (e.g. an alternator, a compressor of an air conditioner, and a water pump) is disposed on a front end portion of the engine body  10 . A rear-side accessory drive device  70  configured to chain-drive a plurality of accessories (e.g. a fuel pump  80 , an oil pump, and a secondary balancer shaft or a primary balancer shaft) is disposed on a rear end portion of the engine body  10 . The rear-side accessory drive device  70  is accommodated in the chain cover  20 . 
     The fuel pump  80  is disposed on a surface of the engine body  10  on the vehicle front side (on the intake side) and on a rear end portion of the engine body  10 . The reason for disposing the fuel pump  80  at the aforementioned position is mainly as follows. A high-pressure fuel injection is necessary in order to enhance controllability of fuel injection as a measure for improving fuel economy of the engine  1 , which is configured to directly inject fuel to a combustion chamber. Therefore, a required drive torque of the fuel pump  80  configured to feed fuel to an injector also increases. It is well-known to dispose the fuel pump  80  at ends of camshafts  41  and  51 , and to drive the fuel pump  80  by using rotations of the camshafts  41  and  51 . However, in a case where a variable valve timing device (VVT) is mounted on the camshafts  41  and  51 , a required drive torque of the fuel pump  80  in a high pressure condition may exceed a torque to be generated by the variable valve timing device. This may make it impossible to operate the variable valve timing device. In view of the above, the fuel pump  80  is disposed at a position other than the ends of the camshafts  41  and  51  while avoiding a high temperature portion such as the exhaust manifold  50 . Further, the fuel pump  80  is disposed on a side surface of the engine body  10  on the intake side, in other words, on a surface of the engine body  10  on the vehicle front side, and on a rear end portion of the engine body  10  where the rear-side accessory drive device  70  is disposed in order to chain-drive the fuel pump  80  by the crankshaft  2 . Note that as a result of the aforementioned configuration, it is necessary to provide a measure for protecting the fuel pump  80  from a collision object from the vehicle front side at vehicle collision (from the front side). In this case, if a dedicated protection member is additionally provided, not only the space for the engine room  100  may be narrowed, but also the weight and the cost of the engine  1  may increase. 
     (1) In view of the above, in the embodiment, the fuel pump  80  configured to feed fuel to an injector, and a starter  90  configured to rotate the crankshaft  2  at an engine start time are disposed on a rear end portion of an intake manifold mounting surface of the engine body  10 , and the starter  90  is disposed to project outwardly with respect to the fuel pump  80  in the engine width direction orthogonal to the cylinder array direction when the engine  1  is viewed from the cylinder array direction in order to protect the fuel pump  80  disposed on a side surface of the engine body  10  on the vehicle front side and on a rear end portion of the engine body  10  from a collision object from the vehicle front side at vehicle collision from the front side, without adding a dedicated member. In other words, the starter  90  is disposed to project forwardly of the vehicle with respect to the fuel pump  80 . 
     Further, in the engine  1  configured such that the fuel pump  80  is disposed on a side surface of the engine body  10  on the intake side and on a rear end portion of the engine body  10 , vibration of the fuel pump  80  in driving the fuel pump  80  and an increase in the engine width should be considered. In this case, if the number of engagement positions of the fuel pump  80  is increased in order to suppress vibration, the number of parts and a time required for assembling may increase. 
     (2) In view of the above, in the embodiment, a transmission engagement rib  13   z  to be engaged with the transmission  30 , and a fuel pump mounting portion  13   f  on which the fuel pump  80  is mounted from the front side are provided on a rear end portion of the engine body  10 ; and a part or the entirety of the fuel pump mounting portion  13   f  is located within an area of a transmission engagement portion  13   g  when the engine  1  is viewed from the cylinder array direction in order to suppress vibration of the fuel pump  80  in driving the fuel pump  80  and an increase in the engine width, which is disposed on a side surface of the engine body  10  on the intake side and on the rear end portion of the engine body  10 , without increasing the number of engagement positions of the fuel pump  80 . 
     Specifically, as illustrated in  FIG. 2 ,  FIG. 4 , and  FIG. 11 , the fuel pump  80  is disposed on the upper front side of the crankshaft  2  on a rear end portion of the engine body  10  when engine body  10  is viewed from a direction of the crankshaft, and the starter  90  is disposed on the lower side of the fuel pump  80 . The fuel pump  80  is located at a relatively upper portion of the cylinder block  13 . Therefore, the fuel pump  80  is disposed relatively proximal to a cylinder bore (not illustrated) in the vehicle front-rear direction. On the other hand, the position of the starter  90  is a position corresponding to a peripheral edge portion of the flywheel  31  (see  FIG. 4  and  FIG. 5 ) on the vehicle front side, which is concentrically mounted on the crankshaft  2 . Therefore, the starter  90  is disposed relatively away from the cylinder bore in the vehicle front-rear direction. Consequently, the starter  90  is disposed to project forwardly of the vehicle with respect to the fuel pump  80 . 
     The fuel pump  80  is mounted on the cylinder block  13 . Specifically, as illustrated in  FIG. 5  and  FIG. 6 , the flange-shaped fuel pump mounting portion  13   f  bulging on the vehicle front side is formed on a rear end portion of the cylinder block  13 , and the fuel pump  80  is mounted on the fuel pump mounting portion  13   f  from the vehicle right side (the side opposite to the transmission) (see  FIG. 3 ). An engagement bolt (not illustrated) for use in mounting the fuel pump  80  passes through an insertion hole formed in a mounting seat of the fuel pump  80  from the vehicle right side (the side opposite to the transmission), and engages in the fuel pump mounting portion  13   f.    
     The fuel pump  80  is chain-driven by the crankshaft  2  with use of the rear-side accessory drive device  70 . Specifically, a drive shaft  81  (see  FIG. 4 ) of the fuel pump  80  passes through an opening  13   x  (see  FIG. 6 ) formed in the fuel pump mounting portion  13   f , and projects into an inner space of the chain cover  20 . Further, a first chain  71  is wound around a first sprocket  82  of a relatively large diameter and mounted on a projection portion of the drive shaft  81 , and a crankshaft sprocket  3  mounted on an end of the crankshaft  2  on the output side and projecting into the inner space of the chain cover  20 . According to this configuration, the fuel pump  80  is chain-driven by the crankshaft  2  via the first chain  71 . Note that in  FIG. 4 , illustration of teeth of sprockets and unit structures of chains is omitted (illustration is also omitted in  FIG. 10 ). 
     The starter  90  is mounted on the chain cover  20 . Specifically, as illustrated in  FIG. 3  and  FIG. 5 , a flange-shaped starter mounting portion  20   f  bulging on the vehicle front side is formed on the chain cover  20  (see  FIG. 6 ). The starter  90  is mounted on the starter mounting portion  20   f  from the vehicle right side (the side opposite to the transmission). An engagement bolt (not illustrated) for use in mounting the starter  90  passes through an insertion hole formed in a mounting seat of the starter  90  from the vehicle right side (the side opposite to the transmission) or from the vehicle left side (the transmission side), and engages in the starter mounting portion  20   f.    
     Note that in the embodiment, the starter mounting portion  20   f  is formed on the chain cover  20 . Alternatively, the starter mounting portion  20   f  may be a plate-shaped member (not illustrated), which is configured to interpose between a rear end portion of the engine body  10  and the chain cover  20 , or between the chain cover  20  and the transmission  30 . 
     Although not illustrated in detail, a pinion gear of the starter  90  passes through an opening formed in the chain cover  20 , projects into an inner space of the transmission  30 , and engages with a ring gear  32  formed on a peripheral edge portion of the flywheel  31 , which is concentrically mounted on the crankshaft  2 . 
     Note that as illustrated in  FIG. 4 , an upper portion of the engine body  10  is slanted at a predetermined angle rearwardly of the vehicle. This is mainly for the purpose of securing a layout space for an intake system including the intake manifold  40 , which is disposed on the vehicle front side. 
     Note that a positional relationship between the starter  90  and the fuel pump  80  may be such that at least the starter  90  projects forwardly of the vehicle with respect to the fuel pump  80  when the engine body  10  is slanted. 
     Further, as illustrated in  FIG. 4 , the intake camshaft  41  and the exhaust camshaft  51  disposed on an upper portion of the cylinder head  12  are chain-driven by the crankshaft  2  with use of the rear-side accessory drive device  70 . Specifically, a second sprocket  83  whose diameter is smaller than the diameter of the first sprocket  82  is mounted on a projection portion of the drive shaft  81  of the fuel pump  80  projecting into an inner space of the chain cover  20 . Further, a second chain  72  is wound around the second sprocket  83 , an intake camshaft sprocket  42  mounted on a projection portion of the intake camshaft  41  projecting into an inner space of the chain cover  20 , and an exhaust camshaft sprocket  52  mounted on a projection portion of the exhaust camshaft  51  projecting into the inner space of the chain cover  20 . According to this configuration, the intake camshaft  41  and the exhaust camshaft  51  are chain-driven by the crankshaft  2  via the first chain  71  and the second chain  72 , which are wound around the fuel pump drive shaft  81 . 
     (3) In the embodiment, a rear end portion of the engine body  10  includes the transmission engagement rib  13   z  to be engaged with the transmission  30 . The fuel pump  80  is disposed on the upper side with respect to the starter  90  in the up-down direction of the engine. At least a part (a vehicle front portion  13   z ′) of the transmission engagement rib  13   z  lies between the fuel pump  80  and the starter  90  (see  FIG. 11 ). 
     Specifically, as illustrated in  FIG. 6 , the transmission engagement portion  13   g  to be engaged with the transmission  30  is formed on a rear end portion of the cylinder block  13 , and the transmission engagement rib  13   z  is formed on an outer peripheral portion of the transmission engagement portion  13   g . The transmission engagement portion  13   g  has an area larger than the area of the fuel pump mounting portion  13   f . The entirety of the fuel pump mounting portion  13   f  is located within the area of the transmission engagement portion  13   g  when the engine  1  is viewed form a direction of the crankshaft. The transmission  30  is mounted on the transmission engagement portion  13   g  from the vehicle left side (the transmission side) (see  FIG. 1  and  FIG. 7 ). Engagement bolts (not illustrated) for use in mounting the transmission  30  pass through insertion holes formed in a mounting seat of the transmission  30  from the vehicle left side (the transmission side), and engage with boss portions  13   y  formed on the transmission engagement rib  13   z.    
     In addition to the above, the fuel pump  80  mounted on the fuel pump mounting portion  13   f  of the cylinder block  13  from the vehicle right side (the side opposite to the transmission) is located on the upper rear side of the vehicle front portion  13   z ′ of the transmission engagement rib  13   z  (a lower portion of a lateral edge portion of the transmission in proximity to the starter  90  in  FIG. 6 ), and the starter  90  mounted on the starter mounting portion  20   f  of the chain cover  20  from the vehicle right side (the side opposite to the transmission) is located on the lower front side of the vehicle front portion  13   z ′. In other words, the fuel pump  80  and the starter  90  are disposed in the up-down direction with respect to the vehicle front portion  13   z′.    
     (4) In the embodiment, the chain cover  20  configured to cover the chains  71  and  72 , and the sprockets  3 ,  42 ,  52 ,  82 , and  83  disposed on a rear end surface of the engine body  10  (in other words, the rear-side accessory drive device  70 ) is mounted between the transmission engagement rib  13   z  and the transmission  30 . Further, the transmission engagement rib  13   z , the chain cover  20 , and the transmission  30  are engaged with each other. 
     Specifically, as illustrated in  FIG. 7 , a flange  30   f  is formed on an end portion of the transmission  30  on the engagement side (in the embodiment, on a right end portion of the transmission  30 ). Engagement bolts  91  pass through the transmission-side flange  30   f  and the chain cover  20  from the vehicle left side (the transmission side) (more specifically, insertion holes formed in a mounting seat of the chain cover  20 ), and engage with the boss portions  13   y  of the transmission engagement rib  13   z  in a state that the chain cover  20  is interposed between the transmission-side flange  30   f , and the transmission engagement rib  13   z  on a rear end portion of the cylinder block  13 . 
     (5) In the embodiment, the transmission engagement portion  13   g  includes the transmission engagement rib  13   z  on an outer peripheral portion thereof. The plurality of boss portions  13   y  through which engagement bolts are inserted are formed on the transmission engagement rib  13   z . The fuel pump mounting portion  13   f  is located between predetermined two of the plurality of boss portions  13   y.    
     Specifically, as illustrated by reference numerals  13   y (α) and  13   y (β) in  FIG. 6  and  FIG. 8 , the fuel pump mounting portion  13   f , the opening  13   x  through which the fuel pump drive shaft  81  is inserted, and the upper rear boss portion  13   y (α) and the lower front boss portion  13   y (β) facing each other with respect to the fuel pump  80  are provided on the transmission engagement rib  13   z  on an outer peripheral portion of the transmission engagement portion  13   g  (see  FIG. 4  and  FIG. 11 ). 
     In this example, in  FIG. 7 , the two boss portions  13   y  engageable with the engagement bolts  91  are the upper boss portion  13   y (α) on the upper side and the lower boss portion  13   y (β) on the lower side. 
     Note that in  FIG. 8 , the reference numerals  13   a  denote fuel pump mounting boss portions. The paired fuel pump mounting boss portions  13   a  are formed on the upper side and the lower side with respect to the opening  13   x  through which the fuel pump drive shaft  81  is inserted, and project on the vehicle right side (toward the side opposite to the transmission) from the fuel pump mounting portion  13   f . Engagement bolts (not illustrated) for use in mounting the fuel pump  80  pass through insertion holes formed in a mounting seat of the fuel pump  80  from the vehicle right side (the side opposite to the transmission), and engage with the fuel pump mounting boss portions  13   a.    
     (6) In the embodiment, along a rear end surface of the engine body  10 , there are provided the crankshaft sprocket  3  mounted on an end of the crankshaft  2 , the first sprocket  82  and the second sprocket  83  mounted side by side on the drive shaft  81  of the fuel pump  80 , the intake camshaft sprocket  42  mounted on the intake camshaft  41 , the first chain  71  wound around the crankshaft sprocket  3  and the first sprocket  82 , and the second chain  72  wound around the second sprocket  83  and the intake camshaft sprocket  42 . 
     Specifically, as illustrated in  FIG. 4 ,  FIG. 9 , and  FIG. 10 , the second chain  72  is wound around the intake camshaft sprocket  42  of the intake camshaft  41  and the exhaust camshaft sprocket  52  of the exhaust camshaft  51 , which are located at a relatively upper position of the engine body  10 ; and the second sprocket  83  of the fuel pump drive shaft  81  located at an intermediate portion of the engine body  10  in the up-down direction of the engine body  10 . Further, the first chain  71  is wound around the first sprocket  82  of the fuel pump drive shaft  81 , and the crankshaft sprocket  3  of the crankshaft  2 . Further, a third chain  73  is wound around the drive sprocket  8  of the crankshaft  2 , a balancer shaft sprocket  7  of a balancer drive shaft  6  located at a relatively lower position of the engine body  10 , and an oil pump sprocket  18  of an oil pump drive shaft  17  within the oil pan  15 . According to this configuration, the fuel pump  80  is chain-driven by the crankshaft  2  via the first chain  71 , and the intake camshaft  41  and the exhaust camshaft  51  are chain-driven by the crankshaft  2  via the first chain  71  and the second chain  72 . Further, although not illustrated, an oil pump, and a secondary balancer shaft or a primary balancer shaft within the oil pan  15  are chain-driven by the crankshaft  2  via the third chain  73 . 
     (7) In the embodiment, the upper boss portion  13   y (α) out of the predetermined two boss portions  13   y (α) and  13   y (β) is located within an area surrounded by the second chain  72  (see  FIG. 11 ). 
     Specifically, as illustrated in  FIG. 4 , the fuel pump mounting portion  13   f , the opening  13   x  through which the fuel pump drive shaft  81  is inserted, and the upper rear boss portion  13   y (α) out of the upper rear boss portion  13   y (α) and the lower front boss portion  13   y (β) facing each other with respect to the fuel pump  80  are located within an area surrounded by the second chain  72 . The upper boss portion  13   y (α) is located on a relatively rear side. Therefore, a front portion of the second chain  72 , out of a pair of front and rear portions of the second chain  72  extending upwardly from the second sprocket  83  mounted on the fuel pump drive shaft  81  is also located on a relatively rear side. This means that the front portion of the second chain  72 , out of the paired front and rear portions of the second chain  72  extending upwardly from the second sprocket  83 , has a larger angle with respect to the intake camshaft sprocket  42 . 
     (8) In the embodiment, the fuel pump  80  and the starter  90  are mounted on an intake manifold mounting surface of the engine  1 . A part of the intake manifold  40  projects outwardly with respect to the fuel pump  80  in the engine width direction when the engine  1  is viewed from a direction of the crankshaft. The intake manifold  40  is disposed on a side surface of the engine body  10  on the vehicle front side in such a manner that a part of the intake manifold overlaps the fuel pump  80  when the engine  1  is viewed from the intake manifold mounting surface. 
     Specifically, as illustrated in  FIG. 3 , the fuel pump  80  extends in the cylinder array direction, and a rear end portion (an end portion on the transmission side) of the engine body  10  projects into an inner space of the chain cover  20 . Further, a front end portion of the engine body  10  projects to a position below the arch of a branch pipe of the intake manifold  40  (see  FIG. 2  and  FIG. 4 ). 
     Next, advantageous effects of the embodiment are described. 
     (1) In the embodiment, in an accessory mounting structure for the engine  1  including the engine body  10  in which the plurality of cylinders #1 to #4 are arranged in a row, and the transmission  30  disposed on an end of the engine body  10  in the cylinder array direction and to which output of the engine  1  is transmitted via the crankshaft  2  of the engine body  10 , when an output side of the crankshaft  2  with respect to the transmission  30  in the cylinder array direction is defined as a rear side, and a side of the crankshaft  2  opposite to the output side is defined as a front side, the fuel pump  80  configured to feed fuel to an injector, and the starter  90  configured to rotate the crankshaft  2  at an engine start time are disposed on a rear end portion of an intake manifold mounting surface of the engine body  10 , and the starter  90  projects outwardly with respect to the fuel pump  80  in the engine width direction orthogonal to the cylinder array direction when the engine  1  is viewed from the cylinder array direction. According to this configuration, the starter  90  comes into contact with a collision object from the vehicle front side prior to the fuel pump  80  at vehicle collision from the front side. Therefore, it is possible to protect the fuel pump  80  without adding a dedicated member. 
     (2) In the embodiment, the rear end portion of the engine body  10  includes the transmission engagement rib  13   z  to be engaged with the transmission  30 . The fuel pump  80  is disposed on the upper side with respect to the starter  90  in the up-down direction of the engine. A least a part (the vehicle front portion  13   z ′) of the transmission engagement rib  13   z  lies between the fuel pump  80  and the starter  90 . According to this configuration, even in a case where a large load is exerted on the starter  90  due to a contact with a collision object from the vehicle front side, and the starter  90  is displaced on the upper side, the aforementioned displacement of the starter  90  is restricted by the vehicle front portion  13   z ′ of the transmission engagement rib  13   z . Therefore, the aforementioned configuration is further advantageous in securely protecting the fuel pump  80 . 
     (3) In the embodiment, the rear end portion of the engine body  10  includes the transmission engagement rib  13   z  to be engaged with the transmission  30 , and the fuel pump mounting portion  13   f  to which the fuel pump  80  is mounted from the front side. A part or an entirety of the fuel pump mounting portion  13   f  is located within an area of the transmission engagement portion  13   g  when the engine  1  is viewed from the cylinder array direction. According to this configuration, a part or the entirety of the fuel pump  80  is mounted within an area of the transmission engagement portion  13   g , whose rigidity is increased by engagement with the transmission  30  on the rear end portion of the engine body  10 . This makes it possible to suppress vibration of the fuel pump  80  in driving the fuel pump  80  and an increase in the engine width, without increasing the number of engagement positions of the fuel pump  80 . 
     (4) In the embodiment, the chain cover  20  configured to cover the chains  71  and  72 , and the sprockets  3 ,  42 ,  52 ,  82 , and  83  disposed on a rear end surface of the engine body  10  is mounted between the transmission engagement rib  13   z  and the transmission  30 . Further, the transmission engagement rib  13   z , the chain cover  20 , and the transmission  30  are engaged with each other. According to this configuration, it is possible to increase the rigidity of the transmission engagement rib  13   z . Therefore, the aforementioned configuration is advantageous in securely restricting the aforementioned displacement of the starter  90 . 
     (5) In the embodiment, the transmission engagement portion  13   g  includes the transmission engagement rib  13   z  on an outer peripheral portion thereof. The plurality of boss portions  13   y  through which engagement bolts are inserted are formed on the transmission engagement rib  13   z . The fuel pump mounting portion  13   f  is located between predetermined two boss portions  13   y (α) and  13   y (β) of the plurality of boss portions  13   y . According to this configuration, the fuel pump  80  is mounted between the two boss portions  13   y (α) and  13   y (β) by which the rigidity of the transmission engagement rib  13   z  is increased by insertion of engagement bolts. Therefore, the aforementioned configuration is further advantageous in securely suppressing vibration of the fuel pump  80  in driving the fuel pump  80 . 
     (6) In the embodiment, along a rear end surface of the engine body  10 , there are disposed the crankshaft sprocket  3  mounted on an end of the crankshaft  2 , the first sprocket  82  and the second sprocket  83  mounted side by side on the drive shaft  81  of the fuel pump  80 , the intake camshaft sprocket  42  mounted on the intake camshaft  41 , the first chain  71  wound around the crankshaft sprocket  3  and the first sprocket  82 , and the second chain  72  wound around the second sprocket  83  and the intake camshaft sprocket  42 . According to this configuration, the fuel pump  80  is chain-driven by the crankshaft  2  via the first chain  71 , and the intake camshaft  41  is chain-driven by the crankshaft  2  via the first chain  71  and the second chain  72 . In this case, at least a part of the fuel pump  80  is mounted within an area of the transmission engagement portion  13   g  on a rear end portion of the engine body  10 . Therefore, as compared with a case where the entirety of the fuel pump  80  is mounted in an area outside the area of the transmission engagement portion  13   g  (in other words, a case where the fuel pump  80  is mounted to project on the intake side of the engine body  10 ), it is possible to secure a sufficient angle of engagement of the second chain  72  with respect to the intake camshaft sprocket  42  (in other words, it is possible to increase the angle). This makes it possible to drive both of the intake camshaft  41  and the exhaust camshaft  51  by the second chain  72 , which does not require a gear between the camshafts. Therefore, it is possible to eliminate gear noise. Further, it is possible to increase the pitch of the second chain  72 . This makes it possible to extend the life of the second chain  72 . 
     (7) In the embodiment, the upper boss portion  13   y (α) out of the predetermined two boss portions  13   y (α) and  13   y (β) is located within an area surrounded by the second chain  72 . According to this configuration, it is possible to increase the angle of engagement of the second chain  72  with respect to the intake camshaft sprocket  42 . Therefore, the aforementioned configuration is advantageous in eliminating the gear noise and in strengthening the function of extending the life of a chain. 
     (8) In the embodiment, the fuel pump  80  and the starter  90  are mounted on the intake manifold mounting surface of the engine  1 . A part of the intake manifold  40  projects outwardly with respect to the fuel pump  80  in the engine width direction when the engine  1  is viewed from a direction of the crankshaft. The intake manifold  40  is disposed on a side surface of the engine body  10  on the vehicle front side in such a manner that a part of the intake manifold  40  overlaps the fuel pump  80  when the engine  1  is viewed from the intake manifold mounting surface. According to this configuration, the intake manifold  40  also serves as a protection member of the fuel pump  80 . Therefore, the aforementioned configuration is advantageous in protecting the fuel pump  80  from a collision object from the vehicle front side by the intake manifold  40 . 
     In the foregoing, the present invention is described in detail by an embodiment. The present invention, however, is not limited to the aforementioned embodiment. For instance, in the embodiment, the entirety of the fuel pump mounting portion  13   f  is located within an area of the transmission engagement portion  13   g  when the engine  1  is viewed from a direction of the crankshaft. Alternatively, a part of the fuel pump mounting portion  13   f  may be located within an area of the transmission engagement portion  13   g  when the engine  1  is viewed from a direction of the crankshaft. 
     Further, the layout of the engine or the type of the vehicle is not specifically limited. For instance, in the embodiment, there is used an FF-vehicle, in which an engine is transversely mounted in such a manner that an intake system is disposed on the vehicle front side, and an exhaust system is disposed on the vehicle rear side. Alternatively, the vehicle may an FF-vehicle, in which an engine is longitudinally mounted. Further alternatively, the vehicle may be an FF-vehicle, in which an engine is transversely mounted, and an intake system is disposed on the vehicle rear side and an exhaust system is disposed on the vehicle front side.