JP2018066301A - Auxiliary machine support structure of engine - Google Patents

Abstract

An object of the present invention is to prevent or suppress the auxiliary machine and the like from getting wet after securing the supporting rigidity of the auxiliary machine. An auxiliary engine support structure for an engine is an auxiliary engine support structure for an engine that supports an alternator 45 as an auxiliary machine to which power is transmitted from an engine main body via a belt. A chain cover 21 that covers the timing chain 22 from the front, and a reinforcing member 55 that bridges the alternator 45 and the chain cover 21 to support the alternator 45 at a position above the oil pan 15. The automatic tensioner 80 </ b> A for adjusting the tension of the belt 42 is attached, and the automatic tensioner 80 </ b> A is located above the oil pan 15. [Selection] Figure 2

Description

  The present invention relates to an auxiliary machine support structure for supporting an auxiliary machine of an engine.

  An auxiliary machine to which power is transmitted from the engine via a belt is disposed around the engine. In the engine accessory drive structure of Patent Document 1, a compressor and a crank pulley are driven and connected by a belt via an idler, and the compressor is fixed to a bracket suspended from the side wall portion of the cylinder block to support the idler. One end of the plate is bridged and fixed to the front portion of the cylinder block, and the other end is fixed to the bracket. The support rigidity of the bracket is secured by supporting the compressor with such a structure.

JP 2004-301011 A

  In the engine accessory drive structure disclosed in Patent Document 1, since the compressor is fixed to a bracket suspended from the side wall portion of the cylinder block, the compressor and the idler are placed below the engine so that they are close to the oil pan. Has been placed. When the compressor and idler are arranged below the engine, there is a possibility that the original function cannot be exhibited due to water exposure.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to prevent or suppress the auxiliary equipment and the like from getting wet after securing the supporting rigidity of the auxiliary equipment.

  The engine accessory support structure of the present invention is an engine accessory support structure that supports an accessory to which power is transmitted from the engine body via a belt, and covers the timing chain from the front of the engine body. A cover and a reinforcing member that bridges the auxiliary machine and the chain cover and supports the auxiliary machine at a position above the oil pan, and the reinforcing member adjusts the tension of the belt. A belt tension adjusting device is attached, and the belt tension adjusting device is located above the oil pan.

  ADVANTAGE OF THE INVENTION According to this invention, after ensuring the support rigidity of an auxiliary machine, it can prevent or suppress that an auxiliary machine etc. get wet.

It is the perspective view which looked at the engine of a present Example from the front diagonal right. It is the figure which looked at the engine of the present Example from the front. It is the figure which looked at the chain cover of a present Example from back. It is the perspective view which shows the structure of the chain adjuster periphery of a present Example which cut | disconnected the II line | wire shown in FIG. 2, and was seen from the right side and back. It is a perspective view which shows the structure of the reinforcement member of a present Example. It is the figure which looked at the engine which removed the reinforcement member from the front. It is a figure which shows the structure of the screw hole periphery of a recessed part among chain covers.

  The embodiment according to the present invention is an engine accessory support structure that supports an alternator 45 as an accessory to which power is transmitted from the engine body 10 via a belt 42, and includes a timing chain from the front of the engine body 10. 22, and a reinforcing member 55 that bridges between the alternator 45 and the chain cover 21 and supports the alternator 45 at a position above the oil pan 15. The reinforcing member 55 includes the belt 42. An auto tensioner 80A for adjusting the tension of the oil pan 15 is attached, and the auto tensioner 80A is positioned above the oil pan 15. According to the auxiliary engine support structure of the engine of the present embodiment, it is possible to prevent or suppress the alternator 45 and the like from being wetted while ensuring the support rigidity of the alternator 45, so that the function of the alternator 45 and the like is continued. Can be demonstrated.

Hereinafter, the present embodiment will be described with reference to the drawings.
FIG. 1 is a perspective view of the engine 100 as viewed from the front diagonal right. FIG. 2 is a view of engine 100 as viewed from the front. In each of the drawings including the following drawings, the direction from the transmission toward the engine along the axial direction of the crankshaft is indicated as the front by the arrow “front”, and the opposite direction is the rear. Further, the direction perpendicular to the cylinder axis and the axis of the crankshaft is indicated by an arrow “left” when viewed from the rear, and the opposite direction is the right. Moreover, the upper direction along the axis of the cylinder is indicated by an arrow “up”, and the opposite direction is the lower side. The arrangement direction of engine 100 is not limited to the illustrated example, and can be appropriately selected according to the vehicle type and the like.

The engine 100 is suspended and coupled to a vehicle body frame (not shown) via a plurality of engine mounts so as to be integrally coupled to the vehicle body frame and mounted in the engine room of the vehicle.
As the engine 100 of this embodiment, for example, a multi-cylinder, typically a three-cylinder DOHC gasoline engine or the like is used. The engine 100 has an engine body 10. The engine body 10 is configured by integrally connecting a cylinder head 12 and a cylinder head cover 13 sequentially to the upper part of a cylinder block 11. The cylinder block 11 has a crank chamber formed therein. A crankshaft 14 (see FIG. 2) is rotatably supported in the crank chamber. In the cylinder block 11, the cylinders are arranged in series in the front-rear direction, and the axis of each cylinder is oriented in a substantially vertical direction. A piston is fitted in the cylinder bore of each cylinder of the cylinder block 11, and the crankshaft 14 rotates as the piston reciprocates in the cylinder bore along the axial direction of the cylinder. The crankshaft 14 rotates clockwise (clockwise) when viewed from the front. An oil pan 15 for storing engine oil is integrally coupled to the lower portion of the cylinder block 11.

  The engine 100 also draws air from the outside air from the engine 100, intake system components that supply clean air (intake air) to the combustion chamber, fuel system components that supply fuel, and exhaust gas after combustion in the cylinder. Has exhaust system parts to discharge. Engine 100 also includes valve-operated parts that drive and control intake valves and exhaust valves.

  The engine 100 has a chain cover 21 coupled to the front side of the engine body 10. The chain cover 21 has a side wall portion 21a that covers the front surfaces of the cylinder block 11 and the cylinder head 12, and a peripheral edge portion 21b along the outer peripheral edge of the side wall portion 21a. The chain cover 21 is coupled to the cylinder block 11 and the cylinder head 12 by fixing the peripheral edge portion 21b via a plurality of fastening bolts so as to be covered with the side wall portion 21a from the front. The chain cover 21 covers a part of the timing chain 22 with the side wall portion 21a.

  FIG. 3 is a view of the chain cover 21 as viewed from the rear. The chain cover 21 has a chain chamber 23 formed in an inner space on the rear side and surrounded by the side wall portion 21a and the peripheral edge portion 21b. A timing chain 22 as an endless annular body is disposed in the chain chamber 23. The timing chain 22 is wound around a cam sprocket 26 coupled to the front end of the intake side camshaft 24, a cam sprocket 27 coupled to the front end of the exhaust side camshaft 25, and a crank sprocket 28 of the crankshaft 14. It is done. Accordingly, the timing chain 22 moves in conjunction with the rotation of the crankshaft 14, the rotation is transmitted via the cam sprockets 26 and 27, and the intake-side camshaft 24 and the exhaust-side camshaft 25 rotate.

  In the chain chamber 23, a chain guide 29, a tension arm 30, and a chain adjuster 32 as a chain tension adjusting device are disposed around the timing chain 22. The chain guide 29 guides the timing chain 22 to move through a predetermined path. The chain guide 29 is formed long on the top and bottom, and is disposed on the left side in the chain chamber 23, which is the tension side of the timing chain 22. The tension arm 30 applies tension to the timing chain 22 together with the chain adjuster 32. The tension arm 30 is long on the top and bottom, and is disposed on the right side in the chain chamber 23, which is the loose side of the timing chain 22. The tension arm 30 has one end (upper side) in the longitudinal direction supported by the swing shaft 31 and the other end (lower side) swingable in the left-right direction around the swing shaft 31. The chain adjuster 32 has a plunger 33 that biases the tension arm 30 toward the timing chain 22. The plunger 33 constantly urges the tension arm 30 upward and to the left, so that the tension arm 30 swings leftward about the swing shaft 31 and presses the timing chain 22. Therefore, the chain adjuster 32 automatically adjusts the tension of the timing chain 22 so that the tension is always applied to the timing chain 22. The chain adjuster 32 has adjuster mounting portions 34A and 34B that are separated from each other substantially vertically. The adjuster mounting portions 34A and 34B are inserted with fastening bolts 37A and 37B, respectively, and screwed into screw holes formed on the front surface of the cylinder block 11, whereby the chain adjuster 32 is fixed to the front surface of the cylinder block 11.

  FIG. 4 is a perspective view taken along the line I-I shown in FIG. 2 as viewed from the right and from the rear, and shows the configuration around the chain adjuster 32. As shown in FIG. 4, the fastening bolts 37 </ b> A and 37 </ b> B for fixing the chain adjuster 32 each have a screw portion 38 and a head portion 39. For example, hexagon bolts can be used as the fastening bolts 37A and 37B. When the chain adjuster 32 is fixed with the fastening bolts 37 </ b> A and 37 </ b> B, the head 39 comes close to the inside of the side wall portion 21 a of the chain cover 21.

  The chain adjuster 32 has a holding mechanism 35 for holding the urging force of the plunger 33. In some cases, it is desired to remove the camshafts 24 and 25 from the timing chain 22 while the timing chain 22 is engaged with the crank sprocket 28 for maintenance reasons. At this time, the holding mechanism 35 holds the plunger 33 so as not to bias the timing chain 22. The mechanic operates the holding mechanism 35 of the chain adjuster 32 via a special jig, so that the holding mechanism 35 holds the bias of the plunger 33. Here, a service hole 36 is formed in the side wall 21 a of the chain cover 21 so that a maintenance person can access the holding mechanism 35 from the front of the chain cover 21. As shown in FIG. 2, the service hole 36 is located to the right and above the axis Cr of the crankshaft 14. In FIG. 3, the service hole 36 is indicated by a broken line because it is hidden by the chain adjuster 32.

  As shown in FIG. 3, an insertion hole 40 is formed below the side wall 21 a of the chain cover 21 so as to be coaxial with the axis Cr of the crankshaft 14. The front end side of the crankshaft 14 is inserted through the insertion hole 40. A crank pulley 41 fixed to the front end of the crankshaft 14 is disposed in front of the insertion hole 40, that is, at a predetermined distance (first distance) from the front surface of the side wall portion 21a of the chain cover 21. A belt 42 as an endless transmission body is wound around the crank pulley 41. The belt 42 transmits the rotation of the crankshaft 14 to an alternator 45 described later. For example, a V-ribbed belt is used as the belt 42.

As shown in FIG. 2, a water pump attachment portion 43 for attaching a water pump is formed on the front side and the left side of the side wall portion 21 a of the chain cover 21. The water pump is driven according to the rotation of the crankshaft 14 and cools the engine 100 by circulating cooling water.
Further, as shown in FIG. 4, an oil pump mounting portion 44 for mounting the oil pump is formed in the chain chamber 23 of the chain cover 21 and in a space between the insertion hole 40 and the timing chain 22. . The oil pump is driven according to the rotation of the crankshaft 14, and lubricates the movable part of the engine 100 by circulating the engine oil stored in the oil pan 15.

Further, the engine 100 of the present embodiment includes an alternator 45 as an auxiliary machine that is driven by power transmitted from the engine body 10. The alternator 45 of the present embodiment has both a function of a generator that charges a battery by power generation and supplies power to an electrical component, and a function of an electric motor that serves as a drive source for assisting the engine 100 and running the vehicle. .
As shown in FIG. 1, the alternator 45 is supported via an auxiliary machine support structure on the right side of the engine body 10, specifically, on the right side of the cylinder block 11. If the support rigidity of the auxiliary machine support structure is low, the auxiliary machine support structure itself is damaged or noise is generated. Therefore, it is necessary to ensure a high support rigidity. On the other hand, when the alternator 45 is supported at a position where it is easily wetted even if the support rigidity is high, there is a risk of failure due to water exposure. The auxiliary machine support structure of the present embodiment is configured so that the alternator 45 and the like can be prevented or suppressed from getting wet with securing the support rigidity.

Hereinafter, the support structure of the alternator 45 and the surrounding configuration will be described.
First, the alternator 45 includes a substantially cylindrical main body 46 and an alternator pulley 47 positioned in front of the main body 46. The main body 46 has a stator, a rotor, and the like inside, and exhibits functions of a generator and an electric motor. The alternator pulley 47 is connected to the rotor in the main body 46 and rotates around the rotor axis line Ro along the front-rear direction. A part of the belt 42 wound around the crank pulley 41 is wound around the alternator pulley 47.

The alternator 45 has gravity due to the main body 46 having a stator, a rotor, and the like, but is positioned relatively above the engine 100 in order to prevent or suppress water exposure. Specifically, the alternator 45 is located above the oil pan 15 and further above the axis Cr of the crankshaft 14.
The alternator 45 is disposed in the vicinity of the engine body 10 so that the outer shape of the entire engine 100 does not increase. Specifically, the alternator 45 is disposed close to the right side of the cylinder block 11. When the engine 100 is viewed from the left-right direction, the main body 46 of the alternator 45 substantially overlaps the cylinder block 11 and the chain cover 21. On the other hand, the alternator pulley 47 does not overlap the cylinder block 11 and the chain cover 21 and is disposed at a predetermined distance (first distance) from the front surface of the side wall portion 21a of the chain cover 21. Since the alternator pulley 47 and the crank pulley 41 have the same position in the front-rear direction, the belt 42 is wound around the alternator pulley 47 and the crank pulley 41 without being twisted.

Here, as shown in FIG. 2, the alternator pulley 47 is located above and to the right of the crank pulley 41 fixed to the crankshaft 14. On the contrary, the crank pulley 41 is located below and to the left of the alternator pulley 47. Therefore, the belt 42 is stretched between the alternator pulley 47 and the crank pulley 41 obliquely with respect to the vertical direction and the horizontal direction. At this time, as shown in FIG. 2, the service hole 36 described above is exposed inside the belt 42.
Further, the belt 42 is always given tension on the outer peripheral surface thereof by an auto tensioner 80A (first belt tension adjusting device) and 80B (second belt tension adjusting device) as belt tension adjusting devices. The configuration of the auto tensioners 80A and 80B will be described later.

The alternator 45 is supported by the auxiliary machine support structure at the position described above.
Specifically, as shown in FIGS. 1 and 2, the alternator 45 includes a plurality of (for example, three) attachment portions 48 </ b> A to 48 </ b> A that protrude from the outer peripheral surface on the front side of the main body 46 toward the outer side in the radial direction of the main body 46. 48C.
The mounting portion 48A protrudes from the front end and the lower side of the main body portion 46 toward the left diagonally downward. The mounting portion 48A is coupled to the front surface of the peripheral edge portion 21b of the chain cover 21 by fastening bolts 51. Accordingly, the mounting portion 48A is directly supported from below and from the left by the chain cover 21.
The attachment portion 48B protrudes upward from the front side and the upper end of the main body portion 46. The attachment portion 48B is supported by a support member 52 that bridges between the alternator 45 and the chain cover 21. The support member 52 is, for example, a flat steel plate, and in the state where the plate surface is orthogonal to the front-rear direction, one end in the left-right direction is coupled to the mounting portion 48B by a fastening bolt 53, and the other end in the left-right direction is a chain. The cover 21 is coupled to the upper side and the right side by a plurality of fastening bolts 54. Accordingly, the attachment portion 48B is indirectly supported by the chain cover 21 from above via the support member 52.

The attachment portion 48C protrudes from the front end and the lower side of the main body portion 46 toward the lower right side. The mounting portion 48C is supported by a reinforcing member 55 that bridges between the alternator 45 and the chain cover 21.
FIG. 5 is a perspective view showing the configuration of the reinforcing member 55. The reinforcing member 55 is made of, for example, an aluminum alloy and is formed in a substantially bar shape. The reinforcing member 55 has insertion holes 58 and 59 at one end 56 and the other end 57 in the longitudinal direction, respectively. The reinforcing member 55 is the center in the longitudinal direction, has a tensioner mounting portion 60 on one end portion 56 side, and has a connecting portion 61 on the other end portion 57 side. The tensioner attachment portion 60 has a bottomed cylindrical shape, and the auto tensioner 80A is attached from the front. The connecting portion 61 has a plate shape with a substantially constant plate thickness t, and connects the other end portion 57 and the tensioner mounting portion 60.

Here, a state where the reinforcing member 55 is removed from the engine 100 will be described with reference to FIG. 6 is a view showing a state where the reinforcing member 55 is removed from the engine 100 shown in FIG.
As shown in FIG. 6, a screw hole 49 for screwing a fastening bolt 65 inserted through the insertion hole 58 of the reinforcing member 55 is formed in the attachment portion 48 </ b> C. On the other hand, the chain cover 21 is formed with a screw hole 67 for screwing a fastening bolt 66 inserted into the insertion hole 59 of the reinforcing member 55. The screw hole 67 is located on the lower side and the right side of the chain cover 21.

FIG. 7 is a view showing a configuration around the screw hole 67 in the chain cover 21.
The screw hole 67 is formed in a recess 68 that is recessed rearward of the surface of the side wall 21 a of the chain cover 21. The recess 68 is on the lower side and the right side of the chain cover 21 and is close to the lower end and the right end. Further, the recess 68 is located on the right side of the insertion hole 40 and is located on the lower side and the right side of the service hole 36. The recess 68 is surrounded by a bottom surface 69 that is substantially parallel to the surface of the side wall portion 21 a and a wall surface 70 that connects the surface of the side wall portion 21 a and the bottom surface 69. The bottom surface 69 is formed with the screw hole 67 described above. The wall surface 70 is inclined so as to expand toward the front. The wall surface 70 has a curved portion 70a surrounding the screw hole 67 and a straight portion 70b. The straight portion 70b extends obliquely upward and to the right from the curved portion 70a. On the other hand, since the wall surface 70 is missing at the right end, the space of the recess 68 is open toward the right.
The recessed portion 68 is formed so that the end portion 57 of the reinforcing member 55 and a part of the connecting portion 61 can be immersed. That is, the recess 68 has a shape as viewed from the front that is larger than the shape of the end 57 of the reinforcing member 55, and the distance from the surface of the side wall 21 a to the bottom 69 (hereinafter referred to as depth) is the connecting portion of the reinforcing member 55. The plate thickness t is set to be larger than 61.

  Further, as shown in FIG. 3, the region corresponding to the concave portion 68 (the gray portion shown in FIG. 3) in the rear surface of the chain cover 21 has a convex portion 71 that bulges back as much as it is concave from the surface. It is formed. The convex portion 71, like the concave portion 68, is on the lower side and the right side of the chain cover 21 and close to the lower end and the right end. The convex portion 71 has a boss portion 72 at a portion corresponding to the screw hole 67 of the concave portion 68. As shown in FIG. 4, the boss portion 72 protrudes further rearward than the convex portion 71. The screw hole 67 described above is formed in the boss portion 72. As shown in FIG. 3, the boss portion 72 is integrally formed with an extending portion 73 extending to the peripheral edge portion 21 b of the chain cover 21. Here, the boss portion 72 receives a force from the reinforcing member 55 via a fastening bolt 66 screwed into the screw hole 67. Thus, when the screw hole 67 is close to the peripheral edge portion 21b, the extending portion 73 can be easily formed, and the strength of the boss portion 72 can be improved.

  Further, as shown in FIG. 7, when viewed from the front, the recess 68 is formed on the chain adjuster 32 (broken line shown in FIG. 7) arranged on the chain chamber 23 side so that the depth of the recess 68 can be set large. It is located so as not to overlap. Here, the straight line La that connects the center of the fastening bolt 37 </ b> A that fixes the chain adjuster 32 to the cylinder block 11 and the center of the fastening bolt 37 </ b> B does not overlap the recess 68. In particular, of the fastening bolts 37 </ b> A and 37 </ b> B, the fastening bolt 37 </ b> B close to the recess 68 has the head 39 close to the recess 68 (or the protrusion 71 corresponding to the recess 68). Accordingly, the recess 68 is positioned so as not to overlap with the head 39 of the fastening bolt 37B. By setting the positional relationship between the recess 68 and the chain adjuster 32 as described above, the depth of the recess 68 can be set large.

By setting the concave portion 68 as described above, the reinforcing member 55 can be bridged between the alternator 45 and the chain cover 21 in a state where the reinforcing member 55 is immersed in the concave portion 68, thereby supporting the alternator 45. Specifically, one end portion 56 of the reinforcing member 55 is coupled by inserting a fastening bolt 65 through the insertion hole 58 and screwing into the screw hole 49 of the attachment portion 48C. The other end 57 of the reinforcing member 55 is coupled by inserting a fastening bolt 66 through the insertion hole 59 and screwing into the screw hole 67 of the recess 68. Accordingly, the attachment portion 48C is indirectly supported by the chain cover 21 from the lower side and the left side via the reinforcing member 55.
As shown in FIG. 6, when the direction in which the reinforcing member 55 supports the alternator is indicated by a straight line, a straight line L <b> 1 connecting the screw hole 49 and the screw hole 67 is obtained. The inclination direction of the straight line L1 is the same as the straight line L2 that connects the rotor axis line Ro of the alternator 45 and the axis line Cr of the crankshaft 14. In addition, the inclination angle (angle on the acute angle side with respect to the horizontal line) θ1 of the straight line L1 is set slightly smaller than the inclination angle (angle on the acute angle side with respect to the horizontal line) θ2 of the straight line L2.
Thus, when the alternator 45 is supported, the reinforcing member 55 supports the alternator 45 and the chain cover 21 so that the alternator 45 and the chain cover 21 can be bridged, thereby improving the support rigidity when the alternator 45 is supported. Further, the reinforcing member 55 supports the alternator 45 at a position above the oil pan 15, so that the alternator 45 can be prevented from getting wet or suppressed. In a state where the reinforcing member 55 supports the alternator 45, the reinforcing member 55 itself is also located above the oil pan 15.

  Further, as shown in FIG. 2, the auto tensioner 80 </ b> A is attached to the reinforcing member 55 via the tensioner attaching portion 60. That is, the reinforcing member 55 has a function for supporting the alternator 45 and a function of a bracket for attaching the auto tensioner 80A. The auto tensioner 80A is positioned below the belt 42 and presses the belt 42 from below. This position corresponds to the loose side of the belt 42 when the crank pulley 41 rotates the alternator pulley 47 via the belt 42 according to the rotation of the crankshaft 14, that is, when the alternator 45 functions as a generator. The auto tensioner 80A automatically adjusts the tension of the belt 42 so as to always apply tension to the belt 42.

  The auto tensioner 80A has a tensioner body 81, an arm 82, and a tensioner pulley 83, and for example, a mechanical tensioner can be used. The tensioner body 81 includes a friction material using a resin, a spring, and the like. Since the auto tensioner 80A has a resin in the tensioner body 81, it may swell when it is wet. The arm portion 82 is located on the front side of the tensioner main body portion 81 and swings about the swing shaft P. The arm portion 82 is biased toward the belt 42 by the spring of the tensioner main body portion 81. Further, the arm portion 82 has a certain arm length in order to ensure a swing amount. The tensioner pulley 83 is provided at the tip of the arm portion 82 and is rotatable at the rear side.

As shown in FIG. 2, in the auto tensioner 80 </ b> A, the tensioner pulley 83 presses the belt 42 in a state where the arm portion 82 extends from the swing axis P toward the lower left side. At this time, the tensioner pulley 83 presses a position biased toward the crank pulley 41 of the belt 42 that moves on the lower side. In other words, the auto tensioner 80A is attached to the reinforcing member 55 while the length of the arm portion 82 is set so that the tensioner pulley 83 presses the position biased toward the crank pulley 41 side. At this time, the reinforcing member 55 attaches the auto tensioner 80 </ b> A above the oil pan 15 and further above the axis Cr of the crankshaft 14. Therefore, it is possible to prevent or suppress water exposure on the auto tensioner 80A.
The auto tensioner 80 </ b> A is positioned so that the movement trajectory of the tensioner pulley 83 that moves according to the swing of the arm portion 82 does not overlap the service hole 36. In FIG. 2, the movement locus of the tensioner pulley 83 is indicated by a dashed line curve Lb.

  On the other hand, an auto tensioner 80B is disposed on the opposite side of the auto tensioner 80A across the belt 42, that is, on the upper side of the belt 42. The auto tensioner 80B is attached to the chain cover 21 via an attachment member 85 coupled to the side wall portion 21a of the chain cover 21. The auto tensioner 80B presses the belt 42 from above. This position corresponds to the loose side of the belt 42 when the crank pulley is rotated via the belt 42 according to the rotation of the alternator pulley 47, that is, when the alternator 45 functions as an electric motor.

Similar to the auto tensioner 80A, the auto tensioner 80B includes a tensioner main body 81, an arm portion 82, and a tensioner pulley 83. For example, a mechanical tensioner can be used. Although the auto tensioner 80B is different in size from the auto tensioner 80A, the configuration itself is the same, and thus the description of the configuration is omitted.
As shown in FIG. 2, in the auto tensioner 80 </ b> B, the tensioner pulley 83 presses the belt 42 in a state where the arm portion 82 extends obliquely upward and rightward from the swing shaft P. At this time, the tensioner pulley 83 presses a position biased toward the alternator pulley 47 side of the belt 42 moving on the upper side. In other words, the length of the arm portion 82 is set and the auto tensioner 80B is attached to the attachment member 85 so as to press the position where the tensioner pulley 83 is biased toward the alternator pulley 47 side.

  As described above, the auto tensioner 80A and the auto tensioner 80B press the belt 42 at a position biased toward different pulley sides (the crank pulley 41 or the alternator pulley 47). Therefore, even if the belt 42 is extended due to a temperature rise in the engine room, aging deterioration, or the like, it is possible to prevent the upper and lower contacts of each tensioner pulley 83 when the belt 42 is pressed.

Particularly, in the lower auto tensioner 80A, since the tensioner pulley 83 is close to the crank pulley 41 side, the tensioner pulley 83 overlaps the chain cover 21 when viewed from the front. However, since the movement trajectory of the tensioner pulley 83 is set so as not to overlap the service hole 36, the mechanic can access the chain adjuster 32 through the service hole 36 without being affected by the tensioner pulley 83. .
Further, by attaching the auto tensioner 80A in a state where the reinforcing member 55 is immersed in the recessed portion 68, the reinforcing member 55 is inserted into the recessed portion 68 so that the reinforcing member 55 is inserted into the chain cover 21 (or the engine body 10). Can be close. Therefore, the auto tensioner 80 </ b> A attached to the reinforcing member 55 can also be brought close to the chain cover 21. Therefore, the belt 42 to which the tensioner 80A applies tension can also be brought close to the engine body 10, and the size of the entire engine 100 can be reduced in the front-rear direction.

  As described above, according to the auxiliary machinery support structure of the engine of the present embodiment, the reinforcing member 55 supports the alternator 45 in a state where the alternator 45 and the chain cover 21 are bridged. Stiffness can be improved. At this time, since the reinforcing member 55 supports the alternator 45 at a position above the oil pan 15, the alternator 45 can be prevented from being wet or suppressed. The reinforcing member 55 also functions as a bracket for attaching the auto tensioner 80A. At this time, since the reinforcing member 55 has the auto tensioner 80A attached at a position above the oil pan 15, the auto tensioner 80A can be prevented or suppressed from being wet. Thus, according to the auxiliary machinery support structure of the engine of the present embodiment, it is possible to prevent or suppress the alternator 45 and the auto tensioner 80A from getting wet while securing the support rigidity of the alternator 45. Therefore, the functions of the alternator 45 and the auto tensioner 80A can be continuously exhibited.

  Further, according to the auxiliary machinery support structure of the engine of this embodiment, the reinforcing member 55 bridges between the alternator 45 and the chain cover 21 in a state where it is immersed in the recess 68 formed on the front side of the chain cover 21. . Thus, since the reinforcing member 55 can be brought close to the chain cover 21 (or the engine main body 10) by the amount of the reinforcing member 55 immersed in the recess 68, the auto tensioner 80A attached to the reinforcing member 55 is also the engine main body 10. Can be close. Therefore, the belt 42 to which the tensioner 80A applies tension can also be brought close to the engine body 10, and the size of the entire engine 100 can be reduced in the front-rear direction.

  Further, according to the auxiliary machinery support structure for an engine of this embodiment, the recess 68 is formed at a position that does not overlap with the chain adjuster 32 housed in the chain chamber 23 as viewed from the front. As described above, since the recess 68 and the chain adjuster 32 do not overlap, the depth of the recess 68 can be set large. By setting the depth of the recess 68 to be large, the reinforcing member 55 to be immersed in the recess 68 can be brought close to the engine body 10. Therefore, the belt 42 to which the tensioner 80A applies tension can also be brought close to the engine body 10, and the size of the entire engine 100 can be further reduced in the front-rear direction.

Further, according to the auxiliary machinery support structure of the engine of the present embodiment, the auto tensioner 80A attached to the reinforcing member 55 has the service hole 36 for the movement locus of the tensioner pulley 83 to operate the chain adjuster 32 when viewed from the front. It is arranged at a position that does not overlap. Therefore, the mechanic can access the chain adjuster 32 through the service hole 36 without being affected by the tensioner pulley 83.
Further, the engine 100 of this embodiment includes a pair of auto tensioners 80A and 80B with the belt 42 interposed therebetween. At this time, in order to prevent the belt 42 from contacting the upper side and the lower side when the tensioner pulley 83 presses the belt 42, the tensioner pulley 83 of the auto tensioner 80A is arranged close to the crank pulley 41 side. Is arranged. Even in such a case, since the movement trajectory of the tensioner pulley 83 is set so as not to overlap the service hole 36, the mechanic can adjust the chain adjuster through the service hole 36 without being affected by the tensioner pulley 83. 32 can be accessed.

  According to the engine auxiliary machine support structure of the present embodiment, when viewed from the front, the recess 68 overlaps with the head 39 of the fastening bolt 37B for connecting the chain adjuster 32 accommodated in the chain chamber 23 to the engine body 10. It is formed at a position that does not become necessary. Thus, the depth of the recessed part 68 can be set large because the recessed part 68 and the head 39 of the fastening bolt 37B do not overlap.

As mentioned above, although this invention was demonstrated using the Example mentioned above, this invention is not limited only to the Example mentioned above, A change etc. are possible within the scope of the present invention.
In the embodiment described above, an example of a three-cylinder gasoline engine has been described. However, an engine having two cylinders or four cylinders or more may be used.

In the above-described embodiment, the case where the alternator 45 is supported as an auxiliary device has been described. However, the auxiliary device may be a compressor of an air conditioner, a water pump, or the like.
Further, in the above-described embodiment, the case where the alternator 45 has the function of the generator and the function of the motor has been described, but the case may have only the function of the generator. In this case, the auto tensioner 80B for pressing the loose side of the belt 42 when the alternator 45 functions as an electric motor can be omitted.

In the above-described embodiment, the case where the alternator 45 is supported by the chain cover 21 via the mounting portions 48A, 48B, and 48C has been described. However, the present invention is not limited to this case, and the chain cover is provided at another part of the alternator 45. 21 may be supported. Further, the alternator 45 may be supported by the engine body 10.
In the above-described embodiments, the case where mechanical tensioners are used as the auto tensioners 80A and 80B has been described. However, the present invention is not limited to this, and hydraulic tensioners or the like may be used.

100: Engine 10: Engine body 15: Oil pan 21: Chain cover 22: Timing chain 23: Chain chamber 32: Chain adjuster (chain tension adjusting device) 36: Service hole 42: Belt 45: Alternator (auxiliary machine) 55: Reinforcement Member 68: Concave portion 80A: Auto tensioner (first belt tension adjusting device) 80B: Auto tensioner (second belt tension adjusting device) 82: Arm portion 83: Tensioner pulley

Claims (6)

An auxiliary machine support structure for an engine that supports an auxiliary machine to which power is transmitted from the engine body via a belt,
A chain cover that covers the timing chain from the front of the engine body;
A reinforcing member that bridges between the auxiliary machine and the chain cover and supports the auxiliary machine at a position above the oil pan,
The reinforcing member is attached with a belt tension adjusting device for adjusting the tension of the belt,
An auxiliary machinery support structure for an engine, wherein the belt tension adjusting device is located above the oil pan. The chain cover has a recess formed on the front side,
2. The engine accessory support structure according to claim 1, wherein the reinforcing member bridges between the accessory and the chain cover in a state of being immersed in the recess. 3. The chain cover accommodates a chain tension adjusting device that adjusts the tension of the timing chain in a chain chamber located on the rear side,
The engine accessory support structure according to claim 2, wherein the recess is formed at a position not overlapping with the chain tension adjusting device when viewed from the front. The chain cover is provided with a service hole for operating the chain tension adjusting device,
The belt tension adjusting device includes an arm portion that swings around a swing shaft, and a tensioner pulley that contacts the belt and moves in accordance with the swing of the arm portion. The auxiliary machinery support structure for an engine according to claim 3, wherein the movement track of the tensioner pulley is arranged at a position where it does not overlap the service hole. When the belt tension adjusting device is the first belt tension adjusting device, the second belt tension adjusting device adjusts the tension by pressing the belt to the opposite side of the first belt tension adjusting device across the belt. With
The engine accessory support structure according to claim 4, wherein the tensioner pulley of the first belt tension adjusting device is disposed so as to overlap the chain cover when viewed from the front. A fastening bolt for coupling the chain tension adjusting device to the engine body;
6. The engine accessory support structure according to claim 3, wherein when viewed from the front, the concave portion is formed at a position that does not overlap with a head of the fastening bolt. 7.