JP3388109B2 - Oil pan structure in engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil pan structure provided in a lower part of a cylinder block of an engine, mainly a vehicle engine, for storing lubricating oil. Things. 2. Description of the Related Art Conventionally, in a wet sump type engine having an oil pan on the lower surface of a cylinder block, the oil pan is integrally formed and fixed to the lower surface of a crankcase under the cylinder block. (See, for example, JP-A-55-64128). [0003] The oil pan of such a wet sump type engine sufficiently lubricates each lubricated system of the engine, and furthermore, dissipates heat from the oil pan to the outside air to lower the oil temperature. It is necessary to secure enough capacity to store the amount of oil required for this purpose, and therefore, it is desirable that the capacity of the oil pan be large. However, if the capacity of the conventional integrated oil pan is to be increased, the oil pan itself becomes large,
There is a problem that not only the manufacturing cost is increased but also the size of the engine itself is increased. The present invention has been made in view of such circumstances, and a part of a transmission case that covers a timing transmission mechanism for driving a valve operating camshaft of a valve operating system can be used as a part of an oil pan. SUMMARY OF THE INVENTION It is an object of the present invention to provide an oil pan structure in a new engine, in which the above-mentioned problem is solved and a dead space of the engine can be used as a capacity space of an oil pan. In order to achieve the above object, the invention of claim 1 is to transmit a driving force of a crankshaft to one end surface of a cylinder block in a crankshaft direction to a valve operating camshaft. In an engine in which the timing transmission mechanism is provided, and the timing transmission mechanism is covered by a transmission case, an oil pan body having an open end in the crankshaft direction is fixed to the lower surface of the cylinder block. The transmission case is provided with an extension extending below the lower surface of the cylinder block, and the extension is fixed to the opening end face of the oil pan body, and the oil is extended by the extension of the transmission case and the oil pan body. Forming a pan, inclining a bottom surface of the oil pan main body downwardly toward an opening end surface thereof, and forming a boss at a lowermost end of an extension of the transmission case; An oil outlet formed in the boss portion in the direction of the crankshaft and closed by a plug is opened. According to the above feature, the oil pan is constituted by the downward extension of the transmission case and the oil pan body, so that a part (extension) of the transmission case is used as a part of the oil pan. Thus, a sufficient and sufficient amount of lubricating oil can be secured in the oil pan without depending on the size of the oil pan main body. [0008] The particular bottom surface of the oil pan main body, toward the opening end surface is inclined in a descending slope, forming a boss portion at the lowermost end portion of the extension portion of the transmission case, this boss, in the crankshaft direction Since the oil discharge port formed and closed by the plug is opened, the operation of extracting the lubricating oil from the oil pan becomes easy, and the lubricating oil does not remain in the oil pan. The oil outlet is opened to the boss to increase the rigidity of the transmission case itself, and the oil outlet is formed in the crankshaft direction, so that the plug does not protrude downward and the oil pan the distance from the ground is that a secured easily. Embodiments of the present invention will be described below based on embodiments of the present invention shown in the accompanying drawings. This embodiment is an embodiment in which the present invention is applied to an in-line four-cylinder four-stroke engine.
Is a partially broken side view of the engine, FIG. 2 is a partially broken front view of the engine, FIG. 3 is a longitudinal sectional view of the engine taken along line 3-3 in FIG. 1, and FIG. 5 is a partially enlarged view along line 5-5 in FIG. 1, FIG. 6 is a cross-sectional view along line 6-6 in FIG. 5, and FIG. It is a perspective view. 1 to 4, a four-cycle engine E
The engine body 1 has a cylinder block 2, a cylinder head 3 connected to a deck surface thereof by a connecting bolt with a gasket interposed therebetween, and a connecting bolt provided on the lower end surface of the cylinder block 2 on the crankcase side by a packing. And an oil pan (hereinafter simply referred to as an oil pan) 4 integrated with a bearing cap. [0012] As clearly shown in FIG. 3, the width direction before and after That crankshaft opposite sides of the cylinder block 2 and cylinder head 3, hole 7 ₁ through a plurality of bolts that match each other, 17 _1; 7 _2, 17 ₂ are provided side by side in the crankshaft direction.
The three components of the cylinder block 2 and the oil pan 4 are connected to the bolt holes 7 ₁ , 17 ₁ ;
₂ , 17 ₂ , blind screw holes 19 ₁ , formed in a plurality of bearing cap portions 4B _{1 to} 4B ₅ of the oil pan 4.
19 ₂ , a plurality of through bolts 38 ₁ , 38
_They are joined together by _two . As shown in FIGS. 1 and 2, the cylinder block 2 is formed with four cylinder bores 5 arranged in series and a water jacket 6 surrounding the cylinder bores. Bolt through hole 7
_1, 7 ₂ are provided. A piston 8 is provided in the four cylinder bores 5.
There slidably fitted in each, and the cylinder block 2, and the lower end surface of the crank case side, the oil pan body 4 of _a plurality of bearing cap portion 4B ₁ crankshaft 9 between ～4B ₅ is rotatably A connecting rod 10 is connected between the crankpin of the crankshaft 9 and the piston pin of the piston 8. A valve camshaft 11 is rotatably supported on the cylinder head 3. The valve camshaft and intake and exhaust valves 14 and 15 interposed therebetween are operated in a normal manner. Then, there is provided a conventionally known valve operating mechanism 16 which opens and closes them at a predetermined timing. A plurality of bolt insertion holes 17 ₁ , 1 coinciding with the bolt insertion holes 7 ₁ , 7 ₂ on the cylinder block 2 side are provided on both left and right sides of the valve operating cam shaft 11.
7 ₂ is arranged in the crankshaft 9 direction. Further, a head cover 18 that covers the valve mechanism 16 is fixed to the upper surface of the cylinder head 3 via a packing. As shown in FIG. 1, a transmission mechanism 12 is provided between an outer end of the valve operating camshaft 11 and an outer end of the crankshaft 9.
Are connected. The transmission mechanism 12 includes a crankshaft 9.
, A driven sprocket 46 fixed to the outer end of the valve train camshaft 11, and an endless transmission chain 47 suspended between the sprockets 45, 46. The driving force of the crankshaft 9 is transmitted to the valve camshaft 11 via the transmission mechanism 12 with a reduction ratio of 1/2. Also this transmission mechanism 12 is fixed to the transmission case portion 3 ₁ which is formed integrally at one end of the crankshaft direction of the cylinder head 3, a plurality of connecting bolts 29 to one end surface of the crankshaft direction of the cylinder block 2 It is covered by the transmission case 13. The transmission case 13, the extension portion 13e which is extended downward from the cylinder block 2 is integrally formed, the extension portion 13e has a plurality of bolts to the oil pan main body 4 ₁ of the opening end face 24 to be described later 29, the oil pan body 41 and the extension ₁ of the transmission case 13.
An oil pan 4 of the engine E is constituted by 3e. As clearly shown in FIGS. 5 and 6, the extension 13 e of the transmission case 13 has a U-shape in vertical section and projects outward in the crankshaft direction, thereby forming the oil pan chamber Co of the oil pan 4. The capacity is expanded. As shown in FIG. 6, one end of the crankshaft 9 penetrates through the shaft hole 50 of the transmission case 13 and protrudes to the outside. A drive wheel, that is, a drive pulley 48 is fixed to the outer end. , The driving pulley 48 is connected to the endless transmission belt 4.
9 is linked to engine accessories such as a water pump (not shown). The shaft hole 50 of the crankshaft 9 and the transmission case 13
The oil seal means 54 is interposed between the two. In the transmission case 13, another driving sprocket 51 is fixed to the crankshaft 9 adjacent to the driving sprocket 45. The driving sprocket 51 is a driving sprocket 52 of an oil pump Op provided in the oil pan chamber Co. Through an endless chain 53. The oil pan 4 is a main part thereof.
Said oil pan main body 4 _1, Fe, is cast in one piece of a metal material such as Al alloy. This oil pan body 4
Numeral ₁ is integrally connected to the lower surface of the cylinder block 2 by a connecting bolt 35, as shown clearly in FIG.
Bottom wall 20, the left are more formed a right side wall 21, 22 and end walls 23, of the oil pan main body 4 _1, one end face of the transmission mechanism 12 side is open, the open end face 2
4 has a plurality of bolt holes 25 formed therein and is flush with one end face 30 (see FIG. 4) of the cylinder block 2. The transmission case 13 is formed on those faces 24 and 30. A plurality of connecting bolts 29 are used for fixing via packing. And as described above, the oil pan body 4
₁ of the opening end face 24 is covered by the extension portion 13e of the lower portion of the transmission case 13, an oil pan main body 4 _1, by an extension portion 13e of the transmission case 13, an oil pan 4 is formed in the engine E. [0018] The oil in the pan body 4 _1, and presence of the substantially equal intervals in the crankshaft 9 direction, the crankshaft 9 more bearing caps in a direction intersecting the portion 4B ₁ to 4
B ₅ is integrally formed, these bearing cap portion 4B ₁ ~4B ₅ are all be made of a vertical wall relative to the crank shaft 9, and their right and left side end portions, the left , Right side walls 21 and 22 respectively. Bearing cap portion 4B of the one outermost of the oil pan main body 4 ₁ (Mission mounting side) _5, be integral with the oil pan main body 4 ₁ of the end wall 23, forms a part of the end wall 23 ing. The central portion of the upper surface of the plurality of bearing cap portion 4B ₁ ~4B _5, under semicircular bearing halves 26 are formed respectively, under these bearings halves 26, the lower portion of the cylinder block 2 A plurality of semi-circular bearing upper halves 2 formed integrally with the crankcase portion
7, a crank bearing hole 28 for rotatably supporting the crankshaft 9 is formed (see FIG. 3). [0019] in the lower half of the oil pan main body 4 _1, the bottom wall 20, side walls 21 and 22, by a bottom end wall 23 and a plurality of bearing cap portion 4B ₁ ~4B _5, one end in the crankshaft direction There is open, contiguous to its crankshaft direction, is cave-like oil pan chamber Co is formed, the oil pan chamber Co, when the casting of the oil pan main body 4 ₁ integrally mold such core shaped as a hole punching cast by die-cutting, and the inner surface of the oil pan main body 4 ₁ of the bottom wall 20 and the left and right side walls 21 and 22, the bottom surface of the plurality of bearing cap portion 4B ₁ ~4B ₅ includes a crankshaft 9 crossover cross-section is formed in the same shape, and are stamped gradient extending in diverging shape are formed from the oil pan main body 4 _first end wall 23 along the opening end face 24, thereby the oil pan chamber Co
Is formed as an inclined surface having a downward slope from the end wall 23 toward the open end surface 24. Corresponding to the bottom of the oil pan main body 4 ₁ of the opening end face 24, the extension 13 of the transmission case 13
A boss 55 is formed at the lowermost end of e, and an oil outlet 56 is opened in the boss 55, and the oil outlet 56 is closed by screwing a plug, that is, a drain bolt 57. Further, since the transmission case 13 is provided with the oil discharge port 56, the distance of the oil pan 4 from the ground can be easily secured. In particular, since the oil outlet 56 is formed in the direction of the crankshaft, the drain bolt 57 does not project downward. The oil pan chamber Co may be formed as a tunnel-shaped cast hole in which both end walls in the direction orthogonal to the crankshaft direction are open. The plurality of bearing cap portions 4B _1-
Adjacent ones of 4B ₅ are the crankshaft 9
On both left and right sides in a direction perpendicular to the direction, the left and right baffle plates 31 are integrally connected in a bridge-like manner. It extends in the lateral direction so as to partition a part, and suppresses ripples of lubricating oil in the oil pan chamber Co. In addition, the baffle plate on the side where lubricating oil is jumped up by one-way rotation of the crankshaft 9 (FIGS. 2, 3, arrow a direction), that is, in FIG. Reinforcing walls 33 projecting toward the chamber Cc are integrally formed, and these reinforcing walls 33 cooperate with the baffle plate 31 to form the bearing cap portion 4.
Contribute to securing the rigidity of the B ₂ ~4B _5. A pair of rib pieces 34 are integrally formed at both ends of the reinforcing wall 33 in the longitudinal direction.
Helps to prevent the lubricating oil in the oil pan chamber Co from jumping up due to the rotation of the crankshaft 9. [0022] As clearly shown in FIG. 3, the bearing cap portion 4B ₁ ~4B _5, on its upper surface left, opening into their recesses 36 with recesses 36 and 37 are opened to the upper surface, respectively, are formed , The blind screw hole 19 ₁ , 1
9 ₂ are formed and blind screw holes 19 ₁ , 19
₂ , the through bolt 38 is screwed. [0023] As shown in FIG. 3, the bearing cap portion 4B ₁ ~4B _5, the recess 3 on one side of the crankshaft 9
6 forms a lubrication passage 40 in cooperation with a concave portion 39 on one side of the cylinder block 2 side, and lubricating oil in the lubrication passage 40 is supplied to the bearing of the crank 9 and the one side of the crank shaft 9. bolt through holes 7 _1, 17 ₁ and, through bolts 3
Through the oil passage 43 formed between the 8 ₁ is supplied to the lubricated portion of the engine. On the other hand, bearing cap 4B
Of _{1 ~4B 5,} the recess 37 of the other side of the crank shaft cooperates with the other of the recessed portion 41 of the cylinder block 2 side forms an oil passage 42 back communicates with the oil pan chamber Co, this return oil road 42, and the bolt insertion hole 7 _2, 17 ₂ of the other side of the crankshaft 9 is communicated with the oil passage 44 between the through-bolt 38 _2, leads to the oil after lubricating the oil pan chamber Co. On the mounting side of the intake system member In of the engine body 1, the bearing cap 4 of the oil pan 4 is mounted.
The outer surface of the boundary wall portion between B ₁ ~4B ₅ and the oil pan chamber Co, is molded integrally with the spaced crankshaft 9 direction a plurality of thick boss-like mounting portions 61 outwardly The lower portion of the intake manifold as the intake system member In is fixed to these mounting portions 61 by fixing members 62 such as bolts. The intake system member In may be a throttle body, an intake duct, an intake chamber, an air cleaner, or the like, in addition to the intake manifold. In the drawing, Fu is a fuel supply unit having a fuel injection nozzle attached to the intake system member In, and Ex is an exhaust system assembly attached to the other side of the engine body 1. According to the rotation of the crankshaft 9 due to the operation of the wet sump type engine E, the valve train camshaft 11 is driven via the transmission mechanism 12 to operate the valve train 16 and the drive pulley 48 is driven. As a result, an engine accessory such as a water pump is driven via an endless transmission band 49, and an oil pump Op is further driven via the driving sprocket 51, chain 53 and sprocket 52, and the lubricating oil in the oil pan chamber Co is removed. It is sucked up and forcibly supplied to each lubricated portion of the engine E. In the engine E, the transmission mechanism 1
By 2 using an extension portion 13e of the transmission case 13 covering a part of the oil pan 4 is configured, while reducing the size of the oil pan main body 4 ₁ itself is fixed to the lower surface of the cylinder block 2, It is possible to provide an oil pan 4 that can secure a necessary and sufficient amount of lubricating oil. The extension 13 of the transmission case 13 which is a part of the oil pan 4
Since e is formed so as to protrude outward so as to occupy the dead space below the driving pulley 48, the dead space can be effectively used, and the engine E itself does not increase in size. As shown in FIG. 5, the extension 13e of the transmission case 13 covers the lower portion of the drive pulley 48, and also contributes to protection of the drive pulley 48 and the transmission band 49. In particular, the extension 13e is
8, since it protrudes outward beyond the width in the crankshaft direction, the protection of the drive pulley 48 and the transmission band 49 is excellent. Further the oil pan main body 4 ₁ is stamped and formed casting by stamping the mold core or the like, thereby the bottom surface of the oil pan chamber Co is formed on the inclined surface of the downward gradient toward the open end 24 And the extension 1 of the transmission case 13
The provision of the oil discharge port 56 at the lowermost part of 3e not only facilitates the work of extracting the lubricating oil from the oil pan 4 but also prevents the lubricating oil from remaining in the oil pan 4. Further, in opening the oil discharge port 56 in the extension 13e of the transmission case 13,
By forming the boss portion 55 there, the rigidity of the transmission case 13 itself is also increased. [0029] Furthermore the oil pump Op can be assembled therein through the open end face 24 of the oil pan main body 4 _1, workability is improved with the set. In particular the oil pump Op is the open end face 24 of the oil pan main body 4 ₁
It is easy to assemble because it is attached to the bottom side. The cylinder block 2 and the oil pan 4
The to bind together a plurality of through bolts 38 _1, 38 ₂ from the cylinder block 2 side, since carried out by screwing the oil pan main body 4 ₁ of the bearing cap portion 4B ₁ ~4B _5, those bearing on the lower surface of the cap portion 4B ₁ ~4B _5, when the portion protruding downward without thereby casting the oil pan main body 4 _1, below the bearing cap portion 4B ₁ ~4B _5, their parallel Oil pan chamber Co continuous in the direction
Can be cast-molded at once by punching out a molding die such as a core in the direction of the crankshaft 9.
_{1. In} particular, the molding of the oil pan chamber Co is facilitated, so that not only the molding cost can be reduced, but also the oil pan 4 itself can be reduced in weight.
The capacity of the oil pan 4 becomes easy, and the size of the oil pan 4 itself can be reduced. Since there is no need to open a mounting hole such as a bolt hole in the oil pan 4, no sealing means for preventing leakage of lubricating oil is required, the number of parts is reduced, and the oil pan 4 is not required. The required rigidity of itself is secured. Although one embodiment of the present invention has been described above, the present invention is not limited to the embodiment, and various embodiments are possible within the scope of the present invention. For example, in the above embodiment, the case where the present invention is applied to a four-cylinder in-line engine has been described. However, it is needless to say that the present invention can be applied to other types of single-cylinder or multi-cylinder engines. In the embodiment, a chain transmission mechanism is employed as a transmission mechanism for interlocking the crankshaft and the valve operating camshaft, but a gear transmission mechanism, a belt transmission mechanism, or another transmission mechanism may be employed instead. In the above embodiment, the downward slope of the bottom surface of the oil pan main body toward the opening end surface is formed by punching of a molding die. It may be formed. As described above, according to the present invention, since the oil pan is constituted by the downward extension of the transmission case and the oil pan main body, a part (extension) of the transmission case is formed. It can be used as a part of an oil pan, and it is possible to secure a necessary and sufficient amount of lubricating oil in the oil pan while reducing the size of the oil pan body, thereby lubricating each lubricated part of the engine. Therefore, it is possible to secure a sufficient amount of lubricating oil to suppress the temperature rise of the oil. Further the bottom of the oil pan body, especially, toward the opening end surface is inclined in a descending slope, forming a boss portion at the lowermost end portion of the extension portion of the transmission case, the boss portion, the crank shaft direction Since the oil discharge port formed in the oil pan and closed by the plug is opened, the operation of extracting the lubricating oil from the oil pan becomes easy, and the lubricating oil does not remain in the oil pan. The oil outlet is opened to the boss to increase the rigidity of the transmission case itself, and the oil outlet is formed in the crankshaft direction, so that the plug does not protrude downward and the oil pan the distance from the ground is that a secured easily.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially broken side view of the engine. FIG. 2 is a partially broken front view of the engine. FIG. 3 is a longitudinal sectional view of the engine taken along line 3-3 in FIG. 4 is a partial side view of the engine taken along the line 4-4 in FIG. 2 FIG. 5 is a partially enlarged view taken along the line 5-5 in FIG. 1 FIG. 6 is a sectional view taken along the line 6-6 in FIG. ] Perspective view of the oil pan body [Explanation of symbols] 2 ... Cylinder block 4 ... Cylinder head integrated oil pan 4 ₁ ... ... Oil pan body 9 ... Crankshaft 11 ... Valve operated camshaft 12 ... Transmission mechanism 13 Transmission case 13e Extension part (of transmission case) 24 Open end face (of oil pan body) ) 5 .......... boss 56 .......... oil discharge port 57 .......... plug (drain bolt)

Continuation of the front page (56) References JP-A-4-136460 (JP, A) JP-A-8-218935 (JP, A) JP-A-6-272615 (JP, A) Japanese Utility Model Laid-Open No. 59-64415 (JP) , U) Japanese Utility Model 2-14443 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02F 7/00 F01M 11/00 F01M 11/04

Claims (1)

(1) An adjusting mechanism for transmitting the driving force of the crankshaft (9) to the camshaft (11) on one end surface of the cylinder block (2) in the crankshaft direction. In an engine provided with a time transmission mechanism (12) and covering the timing transmission mechanism (12) with a transmission case (13), one end face in the crankshaft direction is opened on the lower surface of the cylinder block (2). The oil pan body (4 ₁ ) is fixed to the transmission case (13), while the extension (13) extends below the lower surface of the cylinder block (2).
e) The provided, the extension portion (13e) and fixed to the open end face (24) of said oil pan body (4 _1), the extension of the transmission case (13) and (13e), an oil pan body (4 ₁ ), an oil pan (4) is formed, and the bottom surface of the oil pan main body (4 ₁ ) is inclined downward toward the opening end surface (24) to thereby form the transmission case (13).
A boss portion (55) is formed at the lowermost end of the extension portion (13e), and an oil discharge port (5) formed in the crankshaft direction and closed by the plug (57) is formed in the boss portion (55).
Characterized in that a 6) is open, the oil in the engine pan structure.