JP2013204471A - Cylinder block structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cylinder block structure capable of fixing a miniaturized transmission with a minimum change.
A cylinder block structure is a cylinder block structure of an engine to which a transmission 5 is joined, and is provided on the transmission side of the cylinder block 2 and has a flange portion 21 having a first joint surface joined to the transmission. A cutout portion 24 is provided at a position facing the accommodating portion 52 of the rotation shaft of the transmission of the cylinder block.
[Selection] Figure 3

Description

  The present invention relates to a cylinder block structure.

  Conventionally, as a cylinder block structure, a cylinder block, a bearing cap that supports a crankshaft mounted on the cylinder block, a cap bolt that fixes the bearing cap to the cylinder block, a beam that supports the bearing cap, and a beam that is a cylinder block And a beam bolt fastened to the skirt portion of the shaft, the beam is fastened to the bearing cap and the cylinder block by the cap bolt, and the cap bolt and the beam bolt are close to each other (for example, Patent Document 1). According to this structure, the rigidity of the cylinder block can be improved.

JP 2005-282467 A

  By the way, the miniaturization of the transmission is currently being studied. When the transmission is downsized, if the conventional cylinder block is used to join the cylinder block and the transmission, the members interfere with each other, which makes it difficult to join. On the other hand, when the transmission is downsized, if the cylinder block is similarly downsized, the cost increases.

  Accordingly, an object of the present invention is to solve the above-described problems of the prior art, and to provide a cylinder block structure capable of mounting a miniaturized transmission with a minimum change.

  The cylinder block structure of the present invention is an engine cylinder block structure to which a transmission is joined, and is provided on the transmission side of the cylinder block, and a flange portion having a first joint surface joined to the transmission includes A cutout portion is provided at a position of the cylinder block facing the receiving portion of the rotation shaft of the transmission.

  In the present invention, the flange portion is provided with a notch portion at a position facing the housing portion of the transmission shaft of the transmission of the cylinder block, so that the transmission can be fixed to the miniaturized transmission with a minimum change. It can be a structure.

  The cylinder block is formed with a second joint surface to which an oil pan is joined, and a first fixing portion that supports a bolt fastened to the end portion of the flange portion from the second joint surface side, and the bolt A fixing member installed in a direction crossing the axial direction of the cylinder, and having a second fixing portion that supports a bolt fastened to the transmission from the cylinder block side, and the transmission and the cylinder block by the fixing member Are preferably joined.

  Although it is conceivable that the notch portion is provided at the end of the flange portion, the jointability of the portion with the transmission is lowered, but in the present invention, the transmission and the cylinder block are connected by the fixing member. By joining, it is possible to improve the jointability and improve the power plant coupling rigidity between the engine and the transmission.

  The oil pan has a flange portion, and the fixing member is connected to the first fixing portion via a support member so as to be parallel to the first fixing portion, and directed toward the second joint surface side. It is preferable that a third fixing portion that supports a bolt that fastens the flange portion and the end portion of the oil pan is supported, and the oil pan and the cylinder block are joined by the third fixing portion. By the third fixing portion, the oil pan and the cylinder block are joined, so that the rigidity can be further improved.

  According to the cylinder block structure of the present invention, it is possible to achieve an excellent effect that a miniaturized transmission can be mounted with a minimum change.

FIG. 2 is a (1) schematic plan view from the exhaust side and (2) a schematic plan view from the front of the engine for explaining the cylinder block structure. It is a typical top view which shows the joint surface with the transmission of a cylinder block. It is a typical lower perspective view of the engine for demonstrating a cylinder block structure. It is (1) typical front view for explaining a fixing member, (2) typical side view from an exhaust side, and (3) typical back view.

  FIG. 1 is a schematic view of an engine for explaining a cylinder block structure. As shown in FIG. 1, the vehicle engine 1 is an in-line multi-cylinder engine, and a plurality of cylinders are formed in a cylinder block 2. A crank pulley 4 connected to a crankshaft is provided on the front surface (front surface) of the cylinder block 2 of the engine 1. A transmission 5 is fixed to the rear surface of the cylinder block 2.

  A cylinder head 6 is provided on the upper surface of the cylinder block 2, and an oil pan 7 is provided on the bottom surface (second bonding surface). A flange portion 71 is provided on the peripheral edge of the oil pan 7, and the flange portion 71 is fixed to the bottom surface of the cylinder block 2 by a bolt 72.

  Thus, the transmission 5 and the oil pan 7 are joined to the cylinder block 2. In the present embodiment, as will be described in detail below, the cylinder block 2, the transmission 5 and the oil pan 7 are fastened together by the fixing member 8 on the exhaust side surface of the cylinder block 2, thereby reducing the size of the transmission 5. The cylinder block 2 is fixed while maintaining rigidity.

  Hereinafter, this embodiment will be described in detail with reference to FIGS.

  The transmission 5 is a transmission that is smaller than the conventional product. That the size is reduced means that the distance between the center of the rotating shaft and the center of the crankshaft 3 is shorter than that of the conventional product. In the case of the transmission 5 provided in the cylinder block according to this embodiment, the distance between the axis center of the rotating shaft and the axis center of the crankshaft 3 is about 10 to 20 mm shorter than the conventional product. The transmission 5 is provided with a bell housing cover 51 as a cover member on the cylinder block 2 side. On the exhaust side surface of the transmission 5, an accommodating portion 52 in which the rotation shaft of the transmission 5 is disposed is provided. That is, the transmission 5 according to the present embodiment is configured such that the distance between the center of the housing portion 52 and the center of the crank pulley 4 is shorter than the conventional one.

  Such a transmission 5 is joined to a flange portion 21 formed on the rear surface side of the cylinder block 2. The rear view of the flange portion 21 will be described with reference to FIG. As shown in FIG. 2, the flange surface of the flange portion 21 on the rear surface side of the cylinder block 2 is a seal surface S (first joint surface) that joins the transmission 5. A portion other than the seal surface S in the flange portion 21 is configured as a region A recessed to the front side. A plurality of bolt holes 22 penetrating the flange portion 21 are formed in the flange portion 21, and bolts (not shown) are inserted into the bolt holes 22 to fix the flange portion 21 and the transmission 5 (see FIG. 1). .

  A notch portion 24 is formed at the exhaust-side end portion 23 of the flange portion 21 where the seal surface S with the transmission 5 is formed. As shown in FIG. 3, the notch 24 is formed in a portion facing the accommodating portion 52 of the transmission 5. That is, in the miniaturized transmission 5, since the distance between the shaft center of the rotating shaft and the shaft center of the crankshaft 3 is short as described above, the rotating shaft installed in the housing portion 52 and the flange portion 21 are in contact with each other. In order to avoid this, the flange portion 21 is provided with a notch 24.

  If the cutout portion 24 is provided in this way, there is no space for providing the sufficient seal surface S and the bolt hole 22 at the end portion 23 on the exhaust side of the flange portion 21. That is, as shown by the dotted line in FIG. 2, the end 23 ′ of the flange 21 when the notch 24 is not formed is wide in the radial direction. Bolt holes 22 'for fixing the sealing surface and the transmission could be provided.

  However, when the transmission 5 as in the present embodiment is joined to the flange portion 21 of the cylinder block 2, there is no space for providing the bolt hole 22 at the end portion 23 by forming the notch portion 24. Therefore, it is necessary to prevent the flange portion 21 and the transmission 5 from being fastened with the bolts at the end portion 23 and the rigidity being lowered to generate vibrations.

  Therefore, in the present embodiment, as shown in FIG. 3, a fixing member 8 that fixes the exhaust-side end portion 23 of the flange portion 21 and the transmission 5 is provided. The fixing member 8 will be described with reference to FIG.

  The fixing member 8 has a holding portion for holding three bolts fastened to fix the three members to each other. First, the fixing member 8 has a first holding part 81. The first holding portion 81 is a columnar member provided with a first through hole 83 in which the first bolt 82 is inserted and held. Further, the fixing member 8 includes a second holding portion 84. The second holding portion 84 is also columnar, and the second holding portion 84 is provided with a second through hole 85, and the second bolt 86 is inserted and held in the second through hole 85. The second holding portion 84 is perpendicular to the axial direction of the first holding portion 81 on the one end side of the first holding portion 81 (the side where the first bolt 82 is inserted). Is provided. That is, the first bolt 82 inserted into the first holding portion 81 and the second bolt 86 inserted into the second holding portion 84 are orthogonal to each other in the axial direction. In addition, the fixing | fixed part in this invention is formed from a holding | maintenance part and a volt | bolt.

  The fixing member 8 includes a third holding part 87. The third holding portion 87 is also columnar, and the third holding portion 87 is provided with a third through hole 88, and the third bolt 89 is inserted and held in the third through hole 88. The third holding portion 87 is supported by the support portion 91 so as to be parallel to the axial direction of the first holding portion 81. That is, the first bolt 82 inserted into the first holding part 81 and the third bolt 89 inserted into the third holding part 87 have the same axial direction and are parallel to each other.

  The support portion 91 is provided with a first beam 92 and a second beam 93 that are parallel to the axial direction of the second holding portion 84, and is configured to ensure the rigidity of the fixing member 8.

  The fixing of the transmission 5 and the flange portion 21 using the fixing member 8 will be described with reference to FIG.

  The second holding portion 84 is connected to the bell housing cover 51 of the transmission 5 so that the first bolt 82 is fastened to the end portion 23 of the flange portion 21. Is fixed so that the second bolt 86 perpendicular to the axial direction is fastened. That is, the transmission 5 and the cylinder block 2 can be fixed by one fixing member 8. Since the fixing member 8 is configured such that the first bolt 82 and the second bolt 86 are orthogonal to each other, the transmission 5 and the cylinder block 2 can be fixed simultaneously. In this case, the fixing member 8 is configured as a separate body and is fixed to each member with a bolt, thereby fixing the end 23 on the exhaust side of the flange portion 21 and the transmission 5 with high rigidity. Can do. Thereby, it is possible to reduce the vibration at the end portion 23 of the flange portion 21 of the cylinder block 2.

  Furthermore, the third holding portion 87 is fixed so that the flange portion 71 of the oil pan 7 and the cylinder block 2 are fastened together by the third bolt 89. Thus, by fixing the oil pan 7 at the same time, it is possible to further improve the rigidity at the end portion 23 of the flange portion 21 and reduce the vibration.

  Thus, in the cylinder block structure in the present embodiment, the transmission 5 can be attached to the cylinder block 2 by providing the notch 24 at the end 23 of the flange portion 21 of the cylinder block 2. That is, by providing the cutout portion 24 in the flange portion 21 of the cylinder block 2 and arranging the accommodating portion 52 in the cutout portion 24, it is possible to attach the miniaturized transmission 5 to the cylinder block 2.

  In this case, since the transmission 5 and the cylinder block 2 cannot be fixed by the sealing surface S of the end portion 23, the transmission 5 and the cylinder block 2 are fixed by using the fixing member 8 in this embodiment. And since it fixes using the fixing member 8 in this way, it is possible to hold | maintain the rigidity in the edge part 23 of the flange part 21, and to improve the power plant joint rigidity of the vehicle engine 1 and the transmission 5. FIG. . Furthermore, since the fixing member 8 fastens the oil pan 7 and the cylinder block 2 together, the rigidity at the end 23 can be further increased.

  The shape of the fixing member 8 used in this embodiment is not limited. The shape of the fixing member 8 is not limited as long as it can fix the transmission 5 and the cylinder block 2 while maintaining rigidity from the lower surface side of the end portion 23.

  Moreover, the flange part 21 of the cylinder block 2 in this embodiment is provided with the convex part 25 which protruded to radial direction on the intake side, as shown in FIG. The convex portion 25 is formed with a concave portion 26 that is recessed toward the front side with respect to the seal surface. By providing such a concave portion 26, the seal surface S constituting the outer edge portion 27 of the convex portion 25 is a thin portion.

  A bridge portion 28 that forms the seal surface S is formed between the recess 26 and the region A. By forming the bridge portion 28, it is possible to improve the rigidity of the end portion 29 on the intake side of the flange portion 21 while further improving the joining property between the transmission and the cylinder block 2. Therefore, the end portion 29 on the intake side of the flange portion 21 has higher rigidity than the conventional one and is formed of a thin portion, so that weight reduction is also realized.

  Furthermore, another concave portion 95 is formed in the flange portion 21, which is recessed toward the front side with respect to the seal surface S even on the exhaust side. Thereby, since the weight of the flange part 21 reduces, weight reduction can be implement | achieved further. Although not shown, a rib is provided on the back side of the convex portion 25 in the cylinder block 2 on the intake side to maintain the rigidity of the cylinder block 2.

  Returning to FIG. 1, in the cylinder block 2 according to the present embodiment, the convex part 96 provided on the transmission 5 side of the exhaust side surface is also formed so as not to contact the rotating shaft like the flange part 21, And the width | variety in the front-back direction is narrower than before. Further, the pair of ribs 97 applied to the convex portions 96 are configured to have the same rib height, so that stress due to the ribs 97 is hardly generated and the rigidity of the cylinder block 2 is improved.

  Thus, the cylinder block 2 in the present embodiment is reduced in weight and rigidity as compared with the conventional one.

DESCRIPTION OF SYMBOLS 1 Engine 2 Cylinder block 3 Crankshaft 4 Crank pulley 5 Transmission 6 Cylinder head 7 Oil pan 8 Fixing member 21 Flange part 22 Bolt hole 23 End part 24 Notch part 51 Bell housing cover 52 Housing part 71 Flange part 72 Bolt 81 1st Holding portion 82 First bolt 83 First through hole 84 Second holding portion 85 Second through hole 86 Second bolt 87 Third holding portion 88 Third through hole 89 Third bolt 91 Support portion 92 First beam 93 Second beam

Claims (3)

A cylinder block structure of an engine to which a transmission is joined,
A flange portion provided on the transmission side of the cylinder block and having a first joint surface joined to the transmission is provided with a notch portion at a position facing the housing portion of the transmission shaft of the cylinder block. Cylinder block structure characterized by The cylinder block has a second joining surface to which an oil pan is joined,
A first fixing portion for supporting a bolt fastened to the end portion of the flange portion from the second joint surface side;
A fixing member that is installed in a direction intersecting with the axial direction of the bolt and has a second fixing portion that supports the bolt fastened to the transmission from the cylinder block side;
The cylinder block structure according to claim 1, wherein the transmission and the cylinder block are joined by the fixing member. The oil pan has a flange portion,
The fixing member is connected to the first fixing portion via a support member so as to be parallel to the first fixing portion, and the flange portion and the end of the oil pan toward the second joint surface side A third fixing portion for supporting a bolt for fastening the portion;
The cylinder block structure according to claim 2, wherein the oil pan and the cylinder block are joined by the third fixing portion.

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