JP6082603B2 - Internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine having an auxiliary machine driven by a camshaft.

  In some internal combustion engines, a drive shaft of an auxiliary machine such as a fuel pump or a distributor is connected to one end of a camshaft, and the auxiliary machine is driven according to the rotation of the camshaft (for example, Patent Documents 1 and 2). ). The drive shaft of the auxiliary machine may be connected to the camshaft via a joint or may be formed integrally with the camshaft.

Japanese Utility Model Publication No. 6-25615 JP 2005-113731 A

  The internal combustion engine as described above has a problem in that the camshaft and the drive shaft of the accessory are arranged coaxially, so that the camshaft becomes longer in the axial direction of the camshaft and the internal combustion engine becomes larger. Further, as in the internal combustion engine according to Patent Document 1, a disc-shaped thrust plate (thrust receiving portion) is provided at the end of the camshaft, and a thrust receiving groove for rotatably receiving the thrust plate is provided in the cylinder head. However, there is a problem that a space for the thrust receiving groove is required, and the cylinder head and the internal combustion engine are further increased in size. Further, since the thrust receiving groove is formed in the cylinder head, there is a problem that the structure of the cylinder head is complicated.

  The present invention has been made in view of the above background, and in an internal combustion engine having an auxiliary machine driven by a camshaft, the support structure of a thrust receiving portion provided on the camshaft is made simple and small. Let it be an issue.

  In order to solve the above problems, the present invention provides an internal combustion engine (1) having an auxiliary machine (12) driven by a camshaft (20), and a plurality of bearing portions that rotatably support the camshaft. A cylinder head (4) provided with (24), and an accessory housing (41) attached to the cylinder head so as to receive one end of the camshaft therein. An end surface (43A) opposite to the side surface (31C) of the one end side bearing portion (24A) arranged closest to the accessory housing among the plurality of bearing portions from the axial direction of the camshaft via a predetermined gap. An extension portion (43) provided, and the camshaft extends in a radial direction, and a thrust receiving portion (35) disposed between a side surface of the one end side bearing portion and an end surface of the extension portion. Special to have To.

  According to this configuration, the thrust receiving portion provided on the camshaft is disposed between the extending portion provided on the auxiliary machine housing and the bearing portion facing the extending portion, and movement in the thrust direction is restricted. Is done. Therefore, it is not necessary to provide the cylinder head with an engaging portion for restricting the thrust receiving portion in the thrust direction. Thereby, size reduction of a cylinder head can be achieved.

  In the above invention, the cylinder head has a side wall portion (29) erected along an edge portion, and the side wall portion has an insertion hole (31A) through which the one end portion of the camshaft passes. The accessory housing is attached to the outer surface of the side wall portion, the extension portion is formed in a cylindrical shape, and the base end communicates with the interior of the accessory housing, while the extension end forms an opening. Then, the one end portion of the camshaft may be received and protruded into the insertion hole, and the end surface may be provided at the extended end.

  According to this configuration, since the extending portion enters the inside of the cylinder head, the coupling stability between the cylinder head and the pump housing is improved.

  In the above invention, the insertion hole may have a predetermined length in the axial direction thereof, extend inward of the cylinder head, and the extension portion may be fitted into the insertion hole. .

  According to this configuration, the coupling stability between the cylinder head and the pump housing is improved by fitting the extending portion into the insertion hole.

  In the above invention, the extending portion has a first through hole (45) penetrating at least partly from the inner surface to the outer surface, and the insertion hole extends from the inner surface to a portion corresponding to the first through hole. You may make it have the 2nd through-hole (67) penetrated inside the said cylinder head.

  According to this configuration, the oil and air staying in the extension portion are discharged into the cylinder head through the first through hole and the second through hole.

  In the above invention, a seal is provided between the outer surface of the extending portion and the inner surface of the insertion hole and on the proximal end side of the extending portion with respect to the first through hole and the second through hole. The member (47) may be interposed.

  According to this configuration, leakage of oil from the joint portion between the extension portion and the insertion hole is suppressed.

  In the above invention, the auxiliary machine is a fuel pump (12), has a pump body (40) supported by the auxiliary machine housing, and the camshaft is located at a portion located in the auxiliary machine housing. And a pump drive cam (37) that rotates together, the pump body has a plunger (54) that is pushed by the pump drive cam and advances and retreats, and the accessory housing receives the plunger so as to advance and retreat. A plunger hole (49) that communicates with the head side lubricating oil passage (86) formed in the cylinder head, and a plunger hole lubricating oil passage (87) that opens to the inner surface of the plunger hole. Also good.

  According to this configuration, the space between the plunger of the fuel pump and the plunger hole is lubricated. In addition, oil is supplied between the plunger and the pump drive cam by the oil that travels along the plunger.

  In the above invention, a plunger hole oil groove (91) extending in the circumferential direction may be formed on the inner surface of the plunger hole, and the plunger hole lubricating oil passage may open to the plunger hole oil groove.

  According to this configuration, sufficient oil is maintained between the plunger and the plunger hole by holding the oil in the plunger hole oil groove.

  According to the above configuration, in the internal combustion engine having the auxiliary machine driven by the camshaft, the support structure of the thrust receiving portion provided on the camshaft can be made simple and small.

1 is a schematic side view showing an internal combustion engine according to a first embodiment. 1 is a schematic plan view showing an internal combustion engine according to a first embodiment. Sectional drawing which shows the cylinder head and fuel pump of the internal combustion engine which concern on 1st Embodiment (III-III sectional drawing of FIG. 2) 1 is an exploded perspective view showing a cylinder head and a fuel pump of an internal combustion engine according to a first embodiment. Sectional drawing which shows the cylinder head and fuel pump of the internal combustion engine which concern on 1st Embodiment Sectional drawing which shows the pump housing of the internal combustion engine which concerns on 1st Embodiment. The side view which shows the pump housing of the internal combustion engine which concerns on 1st Embodiment. Explanatory drawing which shows the oil-path structure of the internal combustion engine which concerns on 1st Embodiment. Sectional drawing which shows the cylinder head and fuel pump of the internal combustion engine which concern on 2nd Embodiment. The disassembled perspective view which shows the connection structure of the cam shaft and pump drive shaft of the internal combustion engine which concerns on 2nd Embodiment. Explanatory drawing which shows the oil-path structure of the internal combustion engine which concerns on 2nd Embodiment.

  Embodiments in which the present invention is applied to an internal combustion engine of an automobile will be described below in detail with reference to the drawings. In the following description, each direction is determined with the traveling direction of the vehicle on which the internal combustion engine is mounted as the front.

(Schematic configuration of the internal combustion engine 1)
FIG.1 and FIG.2 is the schematic side view and schematic plan view which show the internal combustion engine 1 which concerns on embodiment. As shown in FIGS. 1 and 2, the internal combustion engine 1 is a V-type six-cylinder gasoline direct injection engine, and the valve operating mechanism is configured as an SOHC 4 valve. The internal combustion engine 1 is disposed horizontally with respect to the vehicle body so that the axis of a crankshaft (not shown) extends in the left-right direction.

  The internal combustion engine 1 includes a cylinder block 3, a pair of front and rear cylinder heads 4 provided on the top of the cylinder block 3, a pair of front and rear head covers 5 provided on the top of each cylinder head 4, and a lower part of the cylinder block 3. And an oil pan 6 provided. The pair of front and rear cylinder heads 4 constitute a pair of front and rear banks 7 in cooperation with the cylinder block 3. Three cylinders are formed in the cylinder block 3 corresponding to each bank 7. The three cylinders 8 of each bank are arranged in the left-right direction to form a cylinder row extending in the left-right direction.

  As shown in FIG. 2, the rear cylinder head 4 is disposed in the cylinder block 3 so as to be offset to the right with respect to the front cylinder head 4. Further, the left end portion of the rear cylinder head 4 is disposed offset to the right with respect to the left end portion of the cylinder block 3. Thus, a recess 11 is formed on the left side of the rear cylinder head 4 and above the cylinder block 3. A fuel pump 12 that pressurizes fuel and supplies it to an injector (not shown) is attached to the left end of the rear cylinder head 4 and is disposed in the recess 11.

  As shown in FIG. 1, an intake manifold 13 is disposed above the cylinder block 3. The front and rear edges of the intake manifold 13 extend above the front and rear cylinder blocks 3 and the recesses 11. The fuel pump 12 is at least partially disposed below the intake manifold 13. With the above configuration, the fuel pump 12 is surrounded by the cylinder block 3 on the lower side, the intake manifold 13 on the upper side, and the cylinder block 3 on the right side. As a result, when the vehicle collides and the vehicle body is deformed, the fuel pump 12 is protected by the cylinder block 3, the cylinder head 4, and the intake manifold 13, and is difficult to receive a load from the vehicle body and other mounted components.

(Cylinder head configuration)
3 is a cross-sectional view showing the cylinder head 4 and the fuel pump 12 of the internal combustion engine 1 according to the embodiment, and is a cross-sectional view taken along the line III-III in FIG. As shown in FIG. 3, the rear cylinder head 4 has a substantially rectangular parallelepiped lower portion extending in the left-right direction and a box-shaped upper portion provided at the upper end of the lower portion. At the lower part of the cylinder head 4, three combustion chambers 15 opened on the lower surface of the cylinder head 4, extending from the combustion chambers 15 to the front side, intake ports 16 opening to the front surface, and extending from the combustion chambers 15 to the rear side. An exhaust port (not shown) is formed in the rear surface. In the front cylinder head 4, the intake port 16 opens on the rear surface of the cylinder head 4, and the exhaust port opens on the front surface of the cylinder head 4. The upper part of the cylinder head 4 is closed by a head cover 5, and a valve operating chamber 17 is defined between the cylinder head 4 and the head cover 5.

  As shown in FIGS. 1 and 3, the cylinder head 4 is provided with a camshaft 20, an intake rocker shaft 21, and an exhaust rocker shaft 22 in parallel so that their axes extend to the left and right. . As shown in FIG. 3, the camshaft 20 is rotatably supported by a plurality of camshaft bearing portions 24 (five in this embodiment), and rotates in synchronization with the crankshaft. The intake rocker shaft 21 and the exhaust rocker shaft 22 are non-rotatably supported by a plurality of rocker shaft bearing portions 25 provided in the cylinder block 3, and rotatably support a rocker arm 26 that drives the intake valve and the exhaust valve (see FIG. 3). The rocker arm 26 is displaced according to the rotation of the camshaft 20 by a cam 27 provided on the camshaft 20.

  4 is an exploded perspective view showing the cylinder head 4 and the fuel pump 12 of the internal combustion engine 1 according to the embodiment, and FIG. 5 is a cross-sectional view showing the cylinder head 4 and the fuel pump 12 of the internal combustion engine 1 according to the embodiment. . As shown in FIGS. 3 to 5, the upper portion of the rear cylinder head 4 includes a pair of front and rear side walls 28 extending in the left-right direction along the lower front edge and the rear edge, and the lower left edge and the right side. It has a pair of left and right end walls 29 extending in the front-rear direction along the edge. The left end wall 29 has a stepped hole 31 having a circular cross section penetrating in the left-right direction at a portion corresponding to the camshaft 20. The stepped hole 31 has a predetermined length in the left-right direction, has a large-diameter portion 31A (insertion hole) on the left side, and a small-diameter portion 31B (left end side) formed on the right side with a smaller diameter than the large-diameter portion 31A Bearing). The large-diameter portion 31A and the small-diameter portion 31B are arranged coaxially, and an annular thrust receiving surface 31C facing left is formed at the boundary between the large-diameter portion 31A and the small-diameter portion 31B.

  The camshaft 20 has a plurality (five in this embodiment) of journals 34, and the journal 34 arranged on the leftmost side (hereinafter, the leftmost side journal 34 </ b> A) rotates to the small diameter portion 31 </ b> B of the stepped hole 31. Supported as possible. Other journals 34 other than the left end side journal 34 </ b> A are rotatably supported by a camshaft bearing portion 24 provided in the cylinder head 4. The small diameter portion 31B constitutes one of the bearing portions that respectively support the five journals 34, and forms a support surface of the leftmost bearing portion 24A, that is, the leftmost bearing portion 24A. Further, the thrust receiving surface 31C can be said to be the left side surface of the leftmost side bearing portion.

  The camshaft bearing portion 24 other than the small-diameter portion 31B (left end side bearing portion 24A) is formed integrally with the cylinder head 4 and includes a bearing lower portion 24B having a semicircular shaft support portion, and a semicircular shaft support. And a cam cap 24C fastened to the bearing lower portion 24B by a bolt.

  The camshaft 20 has a thrust plate (thrust receiving portion) 35 protruding in the radial direction on the left side of the left end side journal 34A. The thrust plate 35 is formed in a disk shape that is coaxial with the camshaft 20 and has a diameter larger than that of the left end side journal 34A. The left end surface and the right end surface of the thrust plate 35 are formed on a plane orthogonal to the axis of the camshaft 20. The right end surface of the thrust plate 35 is disposed to face the surface of the stepped hole 31.

  The left end portion of the camshaft 20 protrudes to the left of the stepped hole 31 and has a pump drive cam 37 on the left end side of the thrust plate 35. The pump drive cam 37 is a flat cam and is joined to rotate together with the camshaft 20.

(Configuration of fuel pump 12)
As shown in FIG. 4, the fuel pump 12 includes a pump main body 40 and a pump housing 41 for supporting the pump main body 40 on the cylinder head 4. 6 and 7 are a cross-sectional view and a side view showing the pump housing 41 of the internal combustion engine 1 according to the first embodiment. As shown in FIGS. 4-7, the pump housing 41 has the external shape extended in the predetermined direction, and has the housing chamber 42 inside. At one end in the extending direction of the pump housing 41, a cylindrical extending portion 43 is formed in a direction orthogonal to the extending direction. The extending portion 43 has a proximal end portion communicating with the housing chamber 42 and a distal end portion forming an opening. An annular extending end surface 43 </ b> A that forms a plane orthogonal to the axial direction of the extending portion 43 is formed at the distal end portion of the extending portion 43. The extending portion 43 has a constant inner diameter, and the extending portion 43 has a distal end that is reduced in diameter relative to the proximal end. At the distal end portion of the extending portion 43, at least one slit-like cutout portion 45 extending from the extending end surface 43A toward the proximal end side is formed. The notch 45 penetrates from the inner peripheral surface of the extending portion 43 to the outer peripheral surface. An O-ring groove 46 is recessed along the circumferential direction on the outer peripheral surface of the base end portion of the extending portion 43 and on the base end side of the notch portion 45. A flexible O-ring 47 is fitted in the O-ring groove 46.

  A plunger hole 49 is formed substantially along the extending direction of the pump housing 41 at the other end in the extending direction of the pump housing 41. The plunger hole 49 is a cylindrical hole having a predetermined length. The inner end communicates with the housing chamber 42 and the outer end opens on the outer surface of the pump housing 41. As shown in FIG. 7, the pump housing 41 has a planar main body fastening seat 51 around the outer end portion of the plunger hole 49. The main body fastening seat 51 forms a plane orthogonal to the axis of the plunger hole 49.

  As shown in FIGS. 4 and 5, the pump body 40 is a known plunger pump, and is provided with a pump body casing 53 having a fuel passage (not shown) and a check valve, and a pump body casing 53 that can be projected and retracted. And a plunger 54. The pump body 40 draws fuel into the fuel oil passage in the pump body casing 53 when the plunger 54 protrudes from the pump body casing 53, and cooperates with the check valve when the plunger 54 enters the pump body casing 53. It works to pressurize the fuel and send it out of the pump body casing 53.

  A roller holder 57 that rotatably supports the roller 56 is coupled to the tip of the plunger 54. The roller holder 57 is supported from a disc-shaped base portion 57A coupled to the tip of the plunger 54, a pair of support portions 57B projecting in a direction opposite to the plunger 54 side of the base portion 57A, and a peripheral portion of the base portion 57A. It has a cylindrical skirt portion 57C protruding in a direction opposite to the portion 57B side. A support shaft 57D is stretched between the pair of support portions 57B, and a roller 56 is rotatably supported on the support shaft 57D. The base portion 57A is formed with a plurality of oil through holes (not shown) penetrating along the direction in which the plunger 54 advances and retreats. A compression coil spring 59 is interposed between the base 57A and the pump body casing 53. The compression coil spring 59 urges the plunger 54 in a direction protruding from the pump body casing 53 via the roller holder 57.

  The pump body casing 53 is bolted to the body fastening seat 51 in a state where the plunger 54 is inserted into the plunger hole 49 and a part of the pump body casing 53 is fitted to the outer end of the plunger hole 49. The axial directions of the plunger 54 and the plunger hole 49 are the same, and the skirt portion 57 </ b> C of the roller holder 57 is in sliding contact with the inner peripheral surface of the plunger hole 49. A guide groove 61 extending in the axial direction is formed in the plunger hole 49 (see FIG. 7), and a guide convex portion 62 that protrudes into the guide groove 61 is formed on the outer peripheral surface of the skirt portion 57C. (See FIG. 4). The rotation position of the roller holder 57 with respect to the plunger hole 49 is determined by the guide protrusion 62 sliding in the guide groove 61. A part of the roller holder 57 and the roller 56 protrude into the housing chamber 42.

  The pump housing 41 has a fastening surface 64 on the side portion where the extending portion 43 is provided. Each fastening surface 64 is arranged on the base end side with respect to the extending end surface 43 </ b> A in the axial direction of the extending portion 43. In the pump housing 41, the extending portion 43 is inserted into the large diameter portion 31 </ b> A of the stepped hole 31, and the fastening surface 64 is in contact with the fastening seat 65 formed on the outer surface of the left end wall 29 of the cylinder head 4. Thus, the cylinder head 4 is bolted. In a state where the pump housing 41 is fastened to the cylinder head 4, the extending portion 43 extends in the left-right direction, and the plunger hole 49 extends forward and upward from the housing chamber 42. That is, the plunger hole 49 is inclined with respect to the horizontal plane, and the inner end portion is disposed below the outer end portion.

  In a state where the pump housing 41 is fastened to the cylinder head 4, the extending end surface 43 </ b> A of the extending portion 43 is disposed in parallel to each other with a predetermined distance from the thrust receiving surface 31 </ b> C via the thrust plate 35. Thereby, the thrust plate 35 is disposed between the thrust receiving surface 31C and the extended end surface 43A in the axial direction of the camshaft 20, and the movement is restricted in the axial direction of the camshaft 20. The thrust plate 35 is capable of sliding contact with the thrust receiving surface 31C and the extended end surface 43A.

  The extending portion 43 is fitted to the large diameter portion 31A at the base end portion, and the O-ring 47 seals between the outer peripheral surface of the base end portion and the inner peripheral surface of the large diameter portion 31A. A communication passage 67 is formed in the left end wall 29 of the cylinder head 4 to communicate the portion facing the notch 45 of the large diameter portion 31 </ b> A and the valve operating chamber 17.

  The left end portion of the camshaft 20 passes through the extension portion 43, and the pump drive cam 37 is disposed in the housing chamber 42. A roller 56 provided at the tip of the plunger 54 is in rolling contact with the pump drive cam 37. Accordingly, the pump drive cam 37 is rotated by the rotation of the camshaft 20, and the plunger 54 is pressed by the pump drive cam 37 by the roller 56, and moves forward and backward along the plunger hole 49. The fuel pump 12 pumps fuel to the injector as the plunger 54 moves forward and backward. The left end portion of the camshaft 20 functions as a pump drive shaft that drives the fuel pump 12.

(Oil channel structure)
FIG. 8 is an explanatory diagram showing an oil passage structure of the internal combustion engine 1 according to the first embodiment. As shown in FIGS. 1, 2, and 8, an oil pump 71 is provided on the right end surface of the cylinder block 3. The oil pump 71 is driven by rotation of the crankshaft and pumps oil stored in the oil pan 6 to each part of the internal combustion engine 1.

  As shown in FIGS. 1, 2, and 8, a main gallery 72 is formed in the cylinder block 3 in parallel with the crankshaft. The oil pump 71 and the main gallery 72 are connected by an upstream oil passage 74 formed in an end plate (not shown) fastened to the cylinder block or the right end surface of the cylinder block 3. A first oil passage 75 extending to the front and rear cylinder blocks 3 is formed at the right end of the main gallery 72. A second oil passage 76 that extends to the front and rear cylinder blocks 3 is formed at the left end of the main gallery 72.

  As shown in FIGS. 3, 5, and 8, the camshaft 20 has a camshaft oil passage 79 extending in the axial direction therein. The intake rocker shaft 21 and the exhaust rocker shaft 22 have a plurality of intake rocker shaft oil passages 81 and exhaust rocker shaft oil passages 82 that extend in the axial direction inside each of them.

  As shown in FIG. 8, the first oil passage 75 extends to the inside of the right end side bearing portion 24 </ b> D arranged on the rightmost side among the camshaft bearing portions 24 provided in the cylinder head 4. An opening is formed in the support surface of the journal 34. The camshaft oil passage 79 communicates with the journal 34 supported by the right end side bearing portion 24D, and communicates with the first lubricating oil passage. The camshaft oil passage 79 opens to the surface of each journal 34 and supplies oil between each journal 34 and the camshaft bearing portion 24.

  As shown in FIG. 5, the oil supplied from the camshaft oil passage 79 to the left end side bearing portion 24A overflows from the support surface of the left end side bearing portion 24A, and between the thrust plate 35 and the thrust receiving surface 31C, and the thrust. It is supplied between the plate 35 and the extended end face 43A. Of the oil supplied to the thrust plate 35, the thrust receiving surface 31 </ b> C, and the extending end surface 43 </ b> A, excess oil is supplied to the valve operating chamber 17 of the cylinder head 4 via the notch 45 and the communication passage 67 of the extending portion 43. To the oil pan 6 through the oil discharge passage (not shown) formed in the cylinder head 4 and the cylinder block 3.

  The second oil passage 76 communicates with a hydraulic control device 84 provided in the cylinder head 4. As shown in FIG. 3, the hydraulic control device 84 is disposed on the left end wall 29 of the cylinder head 4 and above the fuel pump 12. The hydraulic control device 84 supplies oil to the intake rocker shaft 21 and the exhaust rocker shaft 22 through an oil passage formed in the cylinder head 4. A rocker arm 26 whose operation is controlled by hydraulic pressure is supported on the intake rocker shaft 21 and the exhaust rocker shaft 22. The rocker arm 26 has a drive rocker arm 26A driven by the camshaft 20 and a driven rocker arm 26B that presses an intake valve or an exhaust valve. The driving rocker arm 26A and the driven rocker arm 26B are selectively connected and released by a connecting pin 26C that advances and retreats by hydraulic pressure. The drive rocker arm 26 </ b> A and the driven rocker arm 26 </ b> B are supplied with oil from the hydraulic control device 84 via the intake and exhaust rocker shaft oil passages 82, and are selected to be connected to or released from each other.

  As shown in FIG. 8, the cylinder head 4 is formed with a third oil passage 86 that branches from the second oil passage 76 and opens to the fastening seat 65 of the left end wall 29. As shown in FIGS. 4 to 6, the outer end portion of the housing oil passage 87 is open at the fastening surface 64 of the pump housing 41 corresponding to the third oil passage 86. An annular O-ring groove 88 is formed on the fastening surface 64 so as to surround the outer end portion of the housing oil passage 87, and an O-ring 89 is fitted into the O-ring groove 88. The O-ring 89 is sandwiched between the fastening surface 64 and the fastening seat 65 and seals the connecting portion between the third oil passage 86 and the housing oil passage 87.

  As shown in FIG. 6, an oil groove 91 extending in the circumferential direction is recessed in the inner peripheral surface of the plunger hole 49. The oil groove 91 may be connected in the circumferential direction and may be formed in a closed ring shape, or may be partially cleaved and formed in a C shape. The inner end portion of the housing oil passage 87 opens at the bottom of the oil groove 91. As a result, the oil supplied to the second oil passage 76 sequentially passes through the third oil passage 86, the housing oil passage 87, and the oil groove 91, and is supplied to the inner peripheral surface of the plunger hole 49. Thereby, the space between the skirt portion 57 </ b> C of the roller holder 57 and the inner peripheral surface of the plunger hole 49 is lubricated. The oil groove 91 functions as an oil reservoir (oil dam) and holds oil on the inner peripheral surface of the plunger hole 49.

  Since the axis of the plunger hole 49 is inclined with respect to the horizontal plane, the oil supplied to the inner peripheral surface of the plunger hole 49 and the roller holder 57 moves to the housing chamber 42 side by gravity. Further, the oil between the skirt portion 57 </ b> C and the plunger hole 49 flows toward the housing chamber 42 by the forward / backward movement of the roller holder 57. As a result, oil is supplied between the roller 56 and the support shaft 57D provided at the tip (lower end) of the roller holder 57 and between the roller 56 and the pump drive cam 37, and is lubricated.

  In the internal combustion engine 1 configured as described above, the thrust plate 35 of the camshaft 20 is connected to the thrust receiving surface 31C which is the side surface of the left end side bearing portion 24A and the extended end surface 43A of the extended portion 43 of the pump housing 41. The cam shaft 20 is restricted from moving in the thrust direction by the thrust receiving surface 31C and the extended end surface 43A. Therefore, it is not necessary to form a thrust groove for receiving the thrust plate 35 in the cylinder head 4, and the cylinder head 4 can be shortened in the axial direction of the camshaft 20. In addition, by fastening the pump housing 41 to the cylinder head 4, the movement of the thrust plate 35 in the thrust direction between the pump housing 41 and the cylinder head 4 is restricted. The attachment work to 4 becomes easy.

  The pump main body 40 and the pump housing 41 receive a load along the axial direction of the plunger hole 49 from the pump drive cam 37. Since the extending portion 43 is disposed so as to be orthogonal to the plunger hole 49 and is fitted into the stepped hole 31 of the cylinder head 4, the load received from the pump drive cam 37 is applied to the cylinder head 4 via the extending portion 43. Take over. Therefore, the pump housing 41 is supported by the cylinder head 4 with good stability. Since the extending portion 43 is formed to have a relatively large diameter so that the camshaft 20 can be received, the rigidity of the coupling structure between the extending portion 43 and the stepped hole 31 is relatively high.

  Since the fuel pump 12 receives supply of oil (lubricating oil) through a second oil passage 76 different from the first oil passage 75 communicating with the camshaft oil passage 79, it is sufficient even when the internal combustion engine 1 is started. Oil is supplied quickly, and seizure and uneven wear due to lack of oil are suppressed. In particular, sufficient oil is supplied to the fuel pump 12 more quickly than when oil is supplied to the fuel pump 12 via the camshaft oil passage 79.

  Since the second oil passage 76 that supplies oil to the fuel pump 12 also serves as an oil passage that supplies oil to the intake rocker shaft 21 and the exhaust rocker shaft 22, the oil passage configuration of the internal combustion engine 1 is simplified.

(Second Embodiment)
Hereinafter, the internal combustion engine 100 according to the second embodiment will be described with reference to FIGS. 9 to 11. The internal combustion engine 100 according to the second embodiment differs from the internal combustion engine 1 according to the first embodiment in the configuration of the shaft portion that supports the pump drive cam 37 and the configuration of the pump housing 41. In the following description, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof is omitted.

  9 is a cross-sectional view showing the cylinder head 4 and the fuel pump 12 of the internal combustion engine 100 according to the second embodiment, and FIG. 10 is a connection structure of the camshaft 20 and the pump drive shaft of the internal combustion engine 100 according to the second embodiment. FIG. As shown in FIGS. 9 and 10, the camshaft 101 according to the second embodiment does not have the pump drive cam 37 unlike the camshaft 20 in the first embodiment. On the left side of the camshaft 101, a pump drive shaft 102 is disposed via a slider 103 coaxially with the camshaft 101.

  The pump drive shaft 102 is provided on the left side of the pump drive cam 37, the pump drive cam 37 provided in the middle part in the longitudinal direction (left-right direction), the first journal 105 provided on the right side of the pump drive cam 37. And a second journal 106. The pump drive shaft 102 is rotatably supported by a first bearing portion 107 and a second bearing portion 108 provided in the pump housing 41 in the first and second journals 105 and 106.

  The pump housing 41 according to the second embodiment includes a pump housing left portion 41A having a housing chamber 42, a plunger hole 49, and a second bearing portion 108, and a pump housing right portion 41B having an extending portion 43 and a first bearing portion 107. The pump housing left part 41A and the pump housing right part 41B are fastened to each other. The housing chamber 42 formed in the pump housing left part 41A opens to the right, and the opening is closed by the pump housing right part 41B. The first bearing portion 107 is provided on the proximal end side of the extending portion 43.

  The pump housing right part 41 </ b> B has a first thrust wall 111 projecting leftward into the housing chamber 42 on the left side surface of the first bearing part 107. The left portion 41A of the pump housing has a second thrust wall 112 that protrudes rightward into the housing chamber 42 and whose protruding end face faces the protruding end face of the first thrust wall 111 with a predetermined distance. A pump drive cam 37 is disposed between the first and second thrust walls 111 and 112. When the pump drive cam 37 is in sliding contact with the first and second thrust walls 112 from the left and right directions, the pump drive shaft 102 is restricted from moving in the left and right directions with respect to the first and pump housing right portions 41B.

  A slider 103 that couples the camshaft 101 and the pump drive shaft 102 is housed in the extension 43 of the right portion 41B of the pump housing. The slider 103 has a cylindrical shape and is arranged so that the axis is parallel to the camshaft 101 and the pump drive shaft 102. The right end surface and the left end surface of the slider 103 form a plane orthogonal to the axis. A first convex portion 115 extending in the radial direction of the slider 103 is formed on the right end surface of the slider 103, and a second convex portion 116 extending in the radial direction of the slider 103 is formed on the left end surface. The 1st convex part 115 and the 2nd convex part 116 are arrange | positioned so that each extension direction may become mutually perpendicular | vertical.

  The left end surface of the camshaft 101 is formed on a surface orthogonal to the axis of the camshaft 101, and a first slider groove 117 extending in the radial direction is formed. Both ends of the first slider groove 117 are open on the outer peripheral surface of the camshaft 101. In the first slider groove 117, the first convex portion 115 is slidably received along the longitudinal direction.

  A right end surface of the pump drive shaft 102 is formed on a surface orthogonal to the axis of the pump drive shaft 102, and a second slider groove 118 extending in the radial direction is formed. Both ends of the second slider groove 118 are open to the outer peripheral surface of the pump drive shaft 102. The second projecting portion 116 is received in the second slider groove 118 so as to be slidable along the longitudinal direction.

  The pump drive shaft 102 rotates according to the rotation of the camshaft 101 by the engagement between the first protrusion 115 and the first slider groove 117 and the engagement between the second protrusion 116 and the second slider groove 118. When an axial deviation occurs between the pump drive shaft 102 and the camshaft 101, the first convex portion 115 slides in the first slider groove 117, and the second convex portion 116 is in the second slider groove 118. , The pump drive shaft 102 rotates in parallel with the camshaft 101 with an axial deviation. As described above, the left end portion of the camshaft 101, the slider 103, and the right end portion of the pump drive shaft 102 constitute an Oldham joint.

  Next, the oil passage structure of the internal combustion engine 100 according to the second embodiment will be described. FIG. 11 is an explanatory diagram showing an oil passage structure of the internal combustion engine 100 according to the second embodiment. As shown in FIGS. 9 to 11, the camshaft oil passage 79 has a first slider lubricating oil passage 121 communicating with the first slider groove 117 at the left end portion.

  A fourth oil passage 122 extending to the pump housing 41 branches off from the second oil passage 76 formed in the cylinder block 3. A part of the fourth oil passage 122 is constituted by a pipe 123 spanned between the cylinder block 3 and the right portion 41B of the pump housing. The pump housing right portion 41B is formed with a fifth oil passage 124 that allows the fourth oil passage 122 and the support surface of the second bearing portion 108 to communicate with each other.

  An annular journal oil groove 125 extending in the circumferential direction is formed on the surface of the first journal 105. A drive shaft oil passage 126 is formed in the pump drive shaft 102 along the axial direction. The journal oil groove 125 and the drive shaft oil passage 126 communicate with each other through a communication hole extending in the radial direction in the pump drive shaft 102. The drive shaft oil passage 126 includes a communication hole that extends in the radial direction and opens to the surface of the first journal 105, and a second slider lubricating oil passage 127 that extends in the axial direction and opens in the second slider groove 118. Have.

  A sixth oil passage 129 is formed in the pump housing right portion 41B and the pump housing left portion 41A to communicate the portion corresponding to the journal oil groove 125 of the first bearing portion 107 and the plunger hole 49.

  In the oil path structure described above, the camshaft oil path 79 is interposed between the first slider groove 117 and the first convex 115 via the first slider lubricating oil path 121, and the left end surface of the camshaft 101 and the slider 103. Oil is supplied between the right end surface. Further, oil is supplied between the first bearing 107 and the first journal 105 and to the journal oil groove 125 via the second oil passage 76, the fourth oil passage 122 and the fifth oil passage 124. The oil supplied to the journal oil groove 125 is supplied to the drive shaft oil passage 126 and the sixth oil passage 129. Oil supplied to the drive shaft oil passage 126 passes between the second slider groove 118 and the second convex portion 116 via the second slider lubricating oil passage 127, and the right end surface of the pump drive shaft 102 and the left end of the slider 103. Supplied between the faces. The oil supplied to the drive shaft oil passage 126 is supplied between the second journal 106 and the second bearing portion 108 through the communication hole. The oil supplied to the sixth oil passage 129 is supplied between the inner peripheral surface of the plunger hole 49 and the skirt portion 57 </ b> C of the roller holder 57.

  The oil supplied between the first journal 105 and the first bearing portion 107 and between the second journal 106 and the second bearing portion 108 flows along the first thrust wall 111 and the second thrust wall 112. The first thrust wall 111 moves between the projecting end surface and the left side surface of the pump drive cam 37 and between the projecting end surface of the second thrust wall 112 and the right side surface of the pump drive cam 37 to lubricate.

  The extension part 43 according to the second embodiment restricts the thrust plate 35 between the thrust receiving surface 31C and the camshaft 101 moves in the left-right direction, similarly to the extension part 43 according to the first embodiment. To regulate. As described above, the configuration in which the extension portion 43 regulates the thrust plate 35 between the thrust receiving surface 31 </ b> C is the case where the pump drive cam 37 is provided directly on the camshaft 101, or the cam via the slider 103. Any of the cases where the pump drive cam 37 is provided on the pump drive shaft 102 connected to the shaft 101 can be applied. Further, when the extending portion 43 is fitted into the stepped hole 31, the coupling stability of the pump housing 41 with the cylinder head 4 is improved.

  Since the slider 103 receives supply of oil (lubricating oil) via the cam shaft 101 and the pump drive shaft 102 arranged on the left and right, it is not necessary to form an oil path in the slider 103. Therefore, the slider 103 can increase the rigidity by omitting holes and passages.

  Although the description of the specific embodiment is finished as described above, the present invention is not limited to the above embodiment and can be widely modified. In the first embodiment, oil is supplied to the pump housing 41 through an oil passage formed in the cylinder head 4. In the second embodiment, the pump is supplied from the cylinder block 3 through the pipe 123 without using the cylinder head 4. Although the configuration is such that oil is supplied to the housing 41, various configurations can be applied to the configuration in which the second oil passage 76 and the oil passage of the pump housing 41 are communicated. In the above embodiment, the fuel pump is described as an example of an auxiliary machine. However, a distributor or a water pump may be used as an auxiliary machine instead of the fuel pump.

  DESCRIPTION OF SYMBOLS 1,100 ... Internal combustion engine, 3 ... Cylinder block, 4 ... Cylinder head, 12 ... Fuel pump, 20, 101 ... Camshaft, 21 ... Intake rocker shaft, 22 ... Exhaust rocker shaft, 24 ... Camshaft bearing part, 24A ... Left end side bearing part (one end side bearing part), 24D ... right end side bearing part, 25 ... rocker shaft bearing part, 26 ... rocker arm, 29 ... end wall, 31 ... stepped hole, 31A ... large diameter part (insertion hole), 31B: Small diameter portion, 31C: Thrust receiving surface (side surface), 34 ... Journal, 34A ... Left end side journal, 35 ... Thrust plate (thrust receiving portion), 37 ... Pump drive cam, 40 ... Pump body, 41 ... Pump housing ( Auxiliary machine housing), 41A ... pump housing left part, 41B ... pump housing right part, 42 ... housing chamber, 43 ... extension part, 43A ... extension Surface, 45 ... Notch (first through hole), 46 ... O-ring groove, 47 ... O-ring, 49 ... Plunger hole, 53 ... Pump body casing, 54 ... Plunger, 56 ... Roller, 57 ... Roller holder, 62 ... Guide convex part, 64 ... Fastening surface, 65 ... Fastening seat, 67 ... Communication path (second through hole), 71 ... Oil pump, 72 ... Main gallery, 74 ... Upstream oil path, 75 ... First oil path, 76 2nd oil passage, 79 ... Camshaft oil passage, 81 ... Intake rocker shaft oil passage, 82 ... Exhaust rocker shaft oil passage, 84 ... Hydraulic control device, 86 ... 3rd oil passage (head side lubricating oil passage), 87 ... Housing oil passage (plunger hole lubricating oil passage), 88 ... O-ring groove, 89 ... O-ring, 91 ... oil groove, 103 ... slider, 115 ... first convex portion, 116 ... second convex portion, 117 ... first Slider groove, 118 ... second slice Groove, 121 ... first slider lubricating oil path, 122 ... fourth oil path, 123 ... piping, 124 ... fifth oil path, 125 ... journal oil groove, 126 ... drive shaft oil path, 127 ... second slider lubricating oil path 129 ... 6th oil passage

Claims (4)

An internal combustion engine having an auxiliary machine driven by a camshaft,
A cylinder head comprising a plurality of bearings for rotatably supporting the camshaft;
An accessory housing attached to the cylinder head so as to receive one end of the camshaft inside,
The cylinder head has a side wall portion erected along an edge portion,
The side wall has an insertion hole through which the one end of the camshaft passes,
The auxiliary machine housing is attached to the outer surface of the side wall part, and the camshaft axis line is arranged through a predetermined gap and a side surface of the one end side bearing part arranged closest to the auxiliary machine housing among the plurality of bearing parts. Having an extension with opposite end faces from the direction,
The cam shaft is flared radially, have a thrust receiving portion disposed between the end surface of the side with the extending portion of said one side bearing portion,
The insertion hole has a predetermined length in the axial direction, and extends inward of the cylinder head.
The extension portion is formed in a cylindrical shape, and a base end communicates with the interior of the accessory housing, while an extension end forms an opening to receive the one end portion of the camshaft and in the insertion hole The first end of the extension end is provided with the end face, and at least part of the first through hole penetrates from the inner surface to the outer surface.
The internal combustion engine, wherein the insertion hole has a second through hole penetrating from the inner surface into the cylinder head at a portion corresponding to the first through hole. Between the outer surface of the extension portion and the inner surface of the insertion hole, a seal member is interposed at a portion closer to the proximal end of the extension portion than the first through hole and the second through hole. The internal combustion engine according to claim 1 . The auxiliary machine is a fuel pump, and has a pump body supported by the auxiliary machine housing,
The camshaft has a pump drive cam that rotates together with a portion located in the accessory housing,
The pump body has a plunger that moves forward and backward by being pressed by the pump drive cam.
The auxiliary machine housing has a plunger hole that receives the plunger so as to be able to advance and retreat, and a plunger hole lubricating oil path that communicates with a head side lubricating oil path formed in the cylinder head and opens on an inner surface of the plunger hole. The internal combustion engine according to claim 1 or 2 , characterized by comprising : The internal combustion engine according to claim 3 , wherein a plunger hole oil groove extending in a circumferential direction is formed on an inner surface of the plunger hole, and the plunger hole lubricating oil passage opens into the plunger hole oil groove.

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