Patent Publication Number: US-10323611-B2

Title: Fuel feeding pipe protection structure

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2017-033585, filed Feb. 24, 2017, entitled “FUEL FEEDING PIPE PROTECTION STRUCTURE.” The contents of this application are incorporated herein by reference in their entirety. 
     TECHNICAL FIELD 
     The present invention relates to a fuel feeding pipe protection structure including: an intake part arranged in such a manner as to face an engine main body in the longitudinal direction; a fuel feeding pipe arranged between the engine main body and the intake part; and a protection member fixed to the engine main body to protect the fuel feeding pipe from coming into contact with the intake part. 
     BACKGROUND 
     For example, Japanese Patent Application Publication No. 2007-239710 discloses a structure in which, in order to protect an intake manifold and a fuel system member arranged on a side face of a cylinder head of an internal combustion engine from collision load, the intake manifold and fuel system member are covered with a protector from outside, and a protrusion block provided in the protector faces and is allowed to come into contact with an abutting seat provided in the intake manifold, with a gap formed therebetween. 
     SUMMARY 
     The conventional structure not only requires a large and heavy protector that covers most of the side face of the cylinder head, but also requires the protector to have strong rigidity to transmit collision load to the cylinder head, to surely protect the intake manifold and the fuel system member. This leads to a problem of even more increase in weight. 
     It is preferable to protect a fuel feeding pipe of an internal combustion engine from collision load, with a protection member having a light and simple structure. 
     First aspect of the present disclosure provides a fuel feeding pipe protection structure including: an intake part arranged in such a manner as to face an engine main body in a longitudinal direction; a fuel feeding pipe arranged between the engine main body and the intake part; and a protection member fixed to the engine main body to protect the fuel feeding pipe from coming into contact with the intake part, wherein the protection member includes a first fastening part and a second fastening part fastened to the engine main body, a bridging part connecting the first fastening part and the second fastening part and interposed between the intake part and the fuel feeding pipe, a first protrusion protruding in an extending direction of the fuel feeding pipe from the vicinity of the first fastening part, a second protrusion protruding in the same direction as the protruding direction of the first protrusion from the vicinity of the second fastening part, and a third protrusion protruding in the longitudinal direction from the second protrusion and brought into contact with the engine main body. 
     According to another aspect, the intake part includes a handle member fixed to an outer peripheral part of an intake manifold; and when viewed in the longitudinal direction, the handle member overlaps and is allowed to come into contact with a bolt that fastens any one of the first fastening part and the second fastening part to the engine main body. 
     Note that the cylinder head  11  of the embodiment corresponds to the engine main body of the present disclosure, for example, and the stud bolt  27  of the embodiment corresponds to the bolt of the present disclosure, for example. 
     According to the first aspect, the protection member fixed to the engine main body includes the first fastening part and the second fastening part fastened to the engine main body, and the bridging part connecting the first fastening part and the second fastening part and interposed between the intake part and the fuel feeding pipe. Hence, when the intake part is moved toward the engine main body by collision load of the vehicle, the intake part collides with the protection member and does not collide with the fuel piping. This can prevent damage in the fuel feeding pipe. In particular, the protection member includes the first protrusion protruding in the extending direction of the fuel feeding pipe from the vicinity of the first fastening part, the second protrusion protruding in the same direction as the protruding direction of the first protrusion from the vicinity of the second fastening part, and a third protrusion protruding in the longitudinal direction from the second protrusion and brought into contact with the engine main body. Hence, load from the intake part is supported by the first and second protrusions in the vicinity of the high-strength first and second fastening portions, and also the load is surely transmitted not only from the first and second fastening portions, but also from the third protrusion to the engine main body. Accordingly, transmission of collision load to the fuel feeding pipe can be prevented with the protection member having a light and simple structure, and damage in the fuel feeding pipe can be more surely prevented. 
     According to the another aspect, the intake part includes the handle member fixed to the outer peripheral part of the intake manifold, and when viewed in the longitudinal direction, the handle member overlaps and is allowed to come into contact with a bolt that fastens any one of the first fastening part and the second fastening part to the engine main body. Hence, by transmitting collision load from the high-strength handle member to the protection member at three points, which are the first protrusion, the second protrusion, and the bolt, fuel piping can be protected even more surely. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top view of an inline four-cylinder internal combustion engine. 
         FIG. 2  is an enlarged view of a main part of  FIG. 1 . 
         FIG. 3  is a cross-sectional view taken along line  3 - 3  of  FIG. 2 . 
         FIG. 4  is an arrow view in direction  4  of  FIG. 2 . 
         FIG. 5A  and  FIG. 5B  are each a unit drawing of a protection member. 
         FIG. 6  is an explanatory drawing of action at the time of collision corresponding to  FIG. 2 . 
         FIG. 7  is an explanatory drawing of first to third contact points of the protection member. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, an embodiment of the present disclosure will be described with reference to  FIGS. 1 to 7 . Note that in the specification, the longitudinal direction and lateral direction are defined on the basis of an occupant seated in a driver&#39;s seat. 
       FIG. 1  is a top view of an inline four-cylinder internal combustion engine for a vehicle. A head cover  12  and a high pressure pump base  13  are coupled to an upper face of a cylinder head  11  that constitutes an engine main body of the present disclosure. A fuel delivery pipe  14  is arranged along a cylinder bank line L direction on a rear face of the cylinder head  11 . A high pressure fuel pump  15  supported by the high pressure pump base  13 , and a left end of the fuel delivery pipe  14  are connected by a fuel feeding pipe  16 . A synthetic resin intake manifold  17  is arranged along the back of the fuel delivery pipe  14 , a drive-by-wire throttle valve  18  is connected to a left end of the intake manifold  17 , and intake piping  19  is connected to the upstream side of the throttle valve  18 . A protection member  20  for protecting the fuel feeding pipe  16  from collision load is provided on a left end rear face of the cylinder head  11 . 
     As illustrated in  FIGS. 2 to 5B , the protection member  20  is an aluminum alloy cast member, and includes a cylindrical first fastening portion  20   a  positioned at the upper end and extending in the longitudinal direction, a cylindrical second fastening portion  20   b  positioned at the lower end and extending in the longitudinal direction, and a bridging portion  20   c  that connects the first fastening portion  20   a  and the second fastening portion  20   b  in the vertical direction. The protection member  20  is fastened to a left end rear wall of the cylinder head  11 , with an upper bolt  21  penetrating the first fastening portion  20   a  in the longitudinal direction and a lower bolt  22  penetrating the second fastening portion  20   b  in the longitudinal direction. 
     Moreover, the protection member  20  includes a first protrusion  20   d  that protrudes outwardly in a rib shape to the left along the cylinder bank line direction L from the vicinity of the first fastening portion  20   a , a second protrusion  20   e  that protrudes outwardly in a rib shape to the left along the cylinder bank line direction L from the vicinity of the second fastening portion  20   b , and a third protrusion  20   f  that protrudes frontward from a front face of the second protrusion  20   e  and is brought into contact with a seating face  11   a  (see  FIGS. 2 and 4 ) formed on a rear face of the cylinder head  11 . 
     When the protection member  20  formed in this manner is fastened to the rear wall of the cylinder head  11  with the upper bolt  21  and the lower bolt  22 , a space surrounded by the first fastening portion  20   a , the bridging portion  20   c , the second fastening portion  20   b  of the protection member  20 , and the rear wall of the cylinder head  11  is formed, and the fuel feeding pipe  16  is inserted into this space. 
     The throttle valve  18  includes a metal throttle body  24 , a valve body  25  arranged inside the throttle body  24 , and an electric motor  26  that drives the valve element  25 . A square fastening flange  24   a  formed in an outlet end of the throttle body  24  and a square fastening flange  17   a  formed in an inlet end of the intake manifold  17  are brought into contact with each other, and are fastened with four stud bolts  27  protruding from four corners of the fastening flange  24   a  of the throttle body  24  which penetrate bolt holes  17   b  formed in four corners of the fastening flange  17   a  of the intake manifold  17  and are fastened by nuts  28 . 
     The intake manifold  17  includes an annular groove portion  17   c  having a reduced diameter, in a position adjacent to the fastening flange  17   a . Front and rear steel handle members  29 ,  29  are attached along the outer periphery of the annular groove portion  17   c . Each handle member  29  includes a pair of fixed portions  29   a ,  29   a  and a connection portion  29   b  connecting the fixed portions  29   a ,  29   a  and having an L-shaped section. The pair of fixed portions  29   a ,  29   a  are jointly fastened to a side face of the fastening flange  17   a  by use of the two stud bolts  27 ,  27  and the two nuts  28 ,  28 . A longitudinal center part of the connection portion  29   b  of the handle member  29  is curved in an arc shape that curves away from the fastening flange  17   a  (see  FIG. 7 ). 
     The front handle member  29  and the rear handle member  29  are formed into longitudinally plane-symmetric shapes, and are arranged in longitudinally plane-symmetric positions. These handle members  29 ,  29  are provided for a worker to easily hold an end part of the intake manifold  17  during assembly of the internal combustion engine, and have relatively high strength. 
     The intake manifold  17 , throttle valve  18 , and handle members  29 ,  29  constitute an intake part  30  of the present disclosure, for example. 
     Next, effects of the embodiment of the present disclosure configured in the above manner will be described. 
     As illustrated in  FIG. 6 , when the intake part  30  is pushed rearward with the internal combustion engine by collision load at the time of a frontal crash of the vehicle, the throttle valve  18  that protrudes farthest to the rear in the intake part  30  abuts on a dashboard panel (not shown), whereby a frontward reaction load acts on the throttle valve  18  from the dashboard panel. When the throttle valve  18  is pushed frontward by the reaction load, the relatively weak annular groove portion  17   c  continuous with the fastening flange  17   a  of the synthetic resin intake manifold  17  connected to the throttle valve  18  breaks, and the throttle valve  18  moves further toward the cylinder head  11  while being tilted in arrow A direction in  FIG. 6 . As a result, of the two handle members  29 ,  29  left on the throttle valve  18  side, the front handle member  29  abuts on the high-strength protection member  20  attached to the rear face of the cylinder head  11 , whereby the throttle valve  18  is kept from moving any further to the front. Hence, it is possible to prevent the throttle valve  18  from abutting on and damaging the fuel feeding pipe  16 . 
     At this time, as illustrated in  FIG. 7 , the front handle member  29  remaining on the throttle valve  18  side abuts on the protection member  20  positioned at the front thereof, at three points. Specifically, an upper part of the connection portion  29   b  of the handle member  29  abuts on the first protrusion  20   d  in the vicinity of the first fastening portion  20   a  of the protection member  20  at a first contact point, a lower part of the connection portion  29   b  of the handle member  29  abuts on the second protrusion  20   e  in the vicinity of the second fastening portion  20   b  of the protection member  20  at a second contact point, and the lower fixed portion  29   a  of the handle member  29  abuts on a head part of the lower bolt  22  fastening the second fastening portion  20   b  of the protection member  20  at a third contact point. Thus, the reaction load not only is surely transmitted to the cylinder head  11  by being supported by the first protrusion  20   d  and the second protrusion  20   e  in the vicinity of the first fastening portion  20   a  and the second fastening portion  20   b  of the high-strength protection member  20 , but also is directly transmitted to the seating face  11   a  of the cylinder head  11  from the third protrusion  20   f . Hence, it is possible to prevent transmission of the collision load (reaction load from a front bulk head) from the throttle valve  18  to the fuel feeding pipe  16 , to surely prevent damage in the fuel feeding pipe  16 . Moreover, since the protection member  20  is a small, light and simple-shaped member, increase in weight and cost can be minimized. 
     In particular, the third contact point of the protection member  20  is a head part of the lower bolt  22  and has high strength, and the lower fixed portion  29   a  where the handle member  29  abuts on the third contact point is also a high-strength part in the vicinity of a fastening part formed of the stud bolt  27  and the nut  28 . Hence, it is possible to more surely transmit reaction load from the throttle valve  18  to the cylinder head  11  through the protection member  20 , and keep the fuel feeding pipe  16  from being damaged by the reaction load. 
     Additionally, while the throttle valve  18  moves frontward while being tilted in arrow A direction of  FIG. 6  upon breakage of the intake manifold  17 , the first protrusion  20   d  and the second protrusion  20   e  of the protection member  20  protrude leftward, which is the direction in which the throttle valve  18  is tilted, from the first fastening portion  20   a  and the second fastening portion  20   b . Hence, it is possible to more surely bring the handle member  29  into contact with the protection member  20 . For example, transmission of collision load to the fuel feeding pipe  16  can be prevented with the protection member  20  having a light and simple structure, and damage in the fuel feeding pipe  16  can be surely prevented. 
     Although the embodiment of the present invention has been described, various design changes can be made, without departing from the gist of the invention. Although a specific form of embodiment has been described above and illustrated in the accompanying drawings in order to be more clearly understood, the above description is made by way of example and not as limiting the scope of the invention defined by the accompanying claims. The scope of the invention is to be determined by the accompanying claims. Various modifications apparent to one of ordinary skill in the art could be made without departing from the scope of the invention. The accompanying claims cover such modifications. 
     For example, the engine main body of the present disclosure is not limited to the cylinder head  11  of the embodiment, and may be a cylinder block or a head cover. Although the intake part  30  is arranged on the rear side of the cylinder head  11  in the embodiment, it may be arranged on the front side of the cylinder head  11  instead. 
     The intake part  30  of the present disclosure is not limited to the intake manifold  17 , throttle valve  18 , and handle member  29  of the embodiment. 
     Although the third protrusion  20   f  protrudes from the second protrusion  20   e  in the embodiment, it may protrude from the first protrusion  20   d  instead. 
     Although the handle member  29  abuts on the lower bolt  22  upon input of collision load in the embodiment, it may abut on the upper bolt  21  instead. 
     The internal combustion engine to which the present disclosure is applied is not limited to the inline multi-cylinder internal combustion engine of the embodiment, and may be other types of internal combustion engines such as a V-type multi-cylinder internal combustion engine. 
     Upper and lower sides in the present disclosure are not upper and lower sides in the vertical direction. Instead, the cylinder head  11  side with respect to the crankshaft of the internal combustion engine is defined as the upper side, and the opposite side is defined as the lower side.