JP6353679B2 - Internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine characterized by an arrangement structure of an oil pump.

  The internal combustion engine is provided with an oil pump for pumping oil to a lubricating part or the like. The location of the oil pump varies, but Patent Documents 1 and 2 disclose that the oil pump is disposed inside the oil pan. In Patent Document 1, the oil pump is fixed to the bottom surface of the oil pan. In Patent Document 2, the oil pump is fixed to the inner surface of the oil pan.

  Patent Document 2 does not clearly indicate the route through which the oil pumped by the oil pump is sent to the gallery of the cylinder block. However, Patent Document 1 includes an oil passage provided in the oil pan, and the oil pump. It is disclosed that the discharge port and the oil passage are communicated with each other.

  In any case, the oil pump is driven by a chain provided on the crankshaft. Therefore, the rotation shaft of the oil pump is arranged parallel to the crankshaft, and the chain is engaged with a sprocket provided on the rotation shaft. Yes. If the oil pump is disposed inside the oil pan as in Patent Documents 1 and 2, there is an advantage that the engine can be made more compact.

JP-A-10-121930 JP 05-332113 A

  Now, the oil pan may be struck and deformed or damaged, and it may be necessary to replace it there. The oil pump also needs to be repaired or replaced. However, in the configurations of Patent Documents 1 and 2, when replacing the oil pan or repairing the oil pump, first the chain must be removed from the sprocket of the crankshaft, and then the oil pump must be removed. The exchange work was very troublesome.

  In particular, since the chain for the oil pump is small and the sprocket for the crankshaft is located in a narrow space, the chain tensioner must be removed in a narrow space to remove the chain. Installation is very troublesome.

  Also, the oil pump sprocket misalignment occurs due to the oil pump mounting error to the oil pan and the oil pump mounting error to the cylinder block, and the crankshaft and the oil pump sprocket and chain are twisted. There is also a risk of becoming easier.

Further, the structure can be simplified if the oil passage is provided in the oil pan as in Patent Document 1, but in Patent Document 1, since the oil passage of the oil pan is opened at the joint surface with the cylinder block, There is a risk that the sealing performance deteriorates at the outlet and the oil tends to ooze out. The present invention has been made in view of such a current situation.

The present invention includes the configurations of claims 1 and 2. Of these, the invention of claim 1
“It has a cylinder block and an oil pan fixed to the lower surface of the cylinder block, and an oil pump fixed to the cylinder block and exposed to the inside of the oil pan.
While the oil pump has a suction port for sucking oil accumulated in the oil pan and a discharge port for pressurizing and discharging the oil,
The oil pan is formed with an oil passage communicating with the discharge port of the oil pump, and the inlet of the oil passage and the discharge port of the oil pump communicate with each other when the oil pan is fixed to the cylinder block. in the basic configuration that arrangement has been that we, "as,
"The oil pump is disposed directly below one end of the crankshaft, and is fixed to the lower surface of a ladder frame that rotatably holds the crankshaft from below at one end of the cylinder block.
Furthermore, the suction cylinder connected to the suction port is disposed inside the oil pan as compared with the oil pump when viewed from the axial direction of the crankshaft. ''
It is the composition. Therefore, the oil pump is fixed to the cylinder block via the ladder frame.

The invention of claim 2 has the same basic configuration as that of claim 1 ,
“While the discharge port of the oil pump is opened downward, the inlet of the oil passage in the oil pan is opened upward, and the outlet of the oil passage is inside the inner periphery of the oil pan. When the oil pan is fixed to the cylinder block, the outlet of the oil passage communicates with the main gallery of the cylinder block, and the inlet of the oil passage and the outlet of the oil pump Are now communicating "
It is the composition.

  In this invention, it becomes possible to attach auxiliary tools, such as an oil filter and an oil cooler, to an oil pan using the oil path formed in the oil pan. As a result, the oil pan can be effectively used to contribute to the downsizing of the engine and the simplification of the oil system.

  In the present invention, since the oil pump is fixed to the cylinder block, the oil pan can be removed and attached irrespective of the oil pump. In other words, the oil pan can be easily removed and attached without requiring the troublesome work of removing the chain one by one.

  Therefore, it is possible to easily assemble the engine and replace the oil pan. In addition, when attaching and detaching the oil pump, since the chain can be attached and detached without the oil pan, the labor of the operation can be remarkably suppressed. Furthermore, since the oil passage of the oil pan and the discharge port of the oil pump automatically communicate with the attachment of the oil pan, it is not necessary to connect the oil passage, and this aspect is also excellent in workability.

  The connection mode of the oil pump discharge port and the oil passage of the oil pan can be embodied in various ways. However, when the discharge port is opened downward and the inlet of the oil passage is opened upward as in claim 2, By interposing an elastic sealing material such as an O-ring in this, it is possible to easily connect in a state where sealing performance is secured.

  Further, if the outlet of the oil passage is arranged in a cylindrical structure inside the inner periphery of the oil pan as in claim 2, not only can the sealing performance between the oil pan and the cylinder block be securely secured, Even if oil leaks at the joint between the oil passage outlet and the main gallery of the cylinder block, the leaked oil does not leak to the outside, but just flows down to the oil pan. There is no problem of increasing oil consumption. Furthermore, there exists an advantage which can improve the attachment intensity | strength of an oil pan by utilizing a cylindrical boss | hub as a reinforcement.

It is a figure which shows embodiment, (A) is a top view of the oil pan in the state which has arrange | positioned the oil pump, (B) is a top view of only an oil pan. FIG. 2 is a longitudinal front view taken along the line II-II in FIG. 1 (A) with a cylinder block also displayed. FIG. 3 is a vertical side view taken along the line III-III in FIG. 1A in a state in which a cylinder block is also displayed. It is a separation front view. It is a schematic diagram which shows the system | strain of an oil path.

(1). Basic Configuration of Embodiment Next, an embodiment of the present invention will be described with reference to the drawings. The present embodiment is applied to a vehicle internal combustion engine. The internal combustion engine includes a cylinder block 1 and an oil pan 2 as in the prior art, and a flange provided around the oil pan is fixed to the lower surface of the cylinder block 1 with bolts (not shown).

As shown in FIG. 2, the cylinder block 1 are cylinder formed, on the lower surface of the one end portion of the cylinder block, by bolts 4 and fixing the ladder frame 5, a bearing portion formed therebetween 6 , one end of the crankshaft 7 is rotatably held .

As shown in FIG. 1, an oil pump 8 is disposed in a portion of the inside of the oil pan 2 that faces the one end surface 2 a in the direction of the crank axis. As shown in FIG. 2, the oil pump 8 is disposed directly below the crankshaft 7. As shown in FIGS. 2 and 3, the oil pump 8 has a pump housing 9 and a cover housing 10 fixed to the pump housing 9, and an outer rotor 12 and its outer rotor 12 are provided in a pump chamber 11 formed in the pump housing 9. An inner rotor (not shown) disposed on the inner side is disposed, and both rotors 12 are driven by a rotating shaft 13.

  The rotating shaft 13 is arranged in parallel with the crankshaft 7, and one end surface of the rotating shaft 13 protrudes toward one end of FIG. 2a of the oil pan 2. A sprocket 13 'is fixed to the protruding end portion, and the chain is connected to the sprocket 13'. 14 meshes. Needless to say, the chain 14 also meshes with a sprocket (not shown) fixed to the crankshaft 7.

  A sprocket that meshes with the timing chain is also fixed to the outer side or the inner side of the chain on the crankshaft 7, and the timing chain is covered with a front cover. Therefore, the front cover is fixed to the same side of the cylinder block 1 as the one end surface 2 a of the oil pan 2.

As shown in FIG. 1 (A), the entire arrangement is shown in cross section in FIG. 2, the pump housing 9 constituting the oil pump 8 is provided with three cylindrical seats 15 protruding upward. The cylindrical seats 15 are fixed to the lower surface of the ladder frame 5 fixed to the cylinder block 1 with bolts 16 (see FIG. 2) .

  As shown in FIG. 3, an oil suction port 18 opens toward the inside of the oil pan 2 at the upper part of the oil pump 8, and an oil suction cylinder 19 is fitted and attached to the suction port 18. The oil suction cylinder 19 has an inverted L shape with the tip thereof facing downward, and a strainer portion 20 is provided at the tip. The strainer portion 20 is close to the bottom surface of the oil pan 2.

  A discharge port 21 opens downward at the lower end of the pump housing 9 in the oil pump 8, while an oil passage 23 in which an inlet 22 communicates with the discharge port 21 is formed in the oil pan 2. The inlet 22 of the oil passage is formed in an upward boss 24 provided at the bottom of the oil pan 2, and an O-ring 25 as an example of an elastic seal material is interposed on the mating surface between the boss 24 and the pump housing 9. ing.

  An annular groove into which the O-ring 25 is fitted is formed in one of the boss 24 and the pump housing 9, and the other is a flat surface. From the standpoint of preventing falling off during assembly, it is preferable that an annular groove is formed in the boss 24 and the lower surface of the pump housing 9 is a flat surface without the annular groove.

  As shown in FIGS. 1B and 2, the oil pan 2 is located at substantially the same left and right position as the oil passage 23 and inside the inner periphery of the oil pan 2 at a portion close to one longitudinal side surface 2 b. A cylindrical boss 26 is formed at the position where it is located, and its upper end forms an outlet 27 of the oil passage 23. As shown in FIG. 2, the outlet 27 of the oil passage 23 is close to the lower surface of the ladder frame 5 and communicates with a main gallery 28 formed in the ladder frame 5.

  The lower end of the main gallery 28 and the outlet 27 of the oil passage 23 are connected by a bush 29. For this reason, even if the cylindrical boss 26 and the ladder frame 5 are not in contact with each other, the outlet 27 and the main gallery 28 are connected without causing oil leakage. An elastic sealing material such as an O-ring can be interposed as the sealing means.

(2). Utilization Mode of Oil Pan As shown in FIGS. 1 and 4, an oil filter 29 and an oil cooler 30 are attached to one end face 2 a of the oil pan 2 as auxiliary tools for the lubrication system. The oil cooler 30 is a water-cooled type, and there is provided a cooling water inlet 30a and a cooling water inlet 30b. The oil filter 29 is disposed close to the other longitudinal side surface 2 c of the oil pan 2, and the oil filter 29 is disposed substantially in front of the discharge port 21 of the oil pump 8.

  On one end surface 2a of the oil pan 2, a filter inlet hole 31 directed to the oil filter 29, a filter outlet hole 32 through which oil purified by the oil filter 29 is discharged, a cooler inlet hole 33 directed to the oil cooler 30, and oil A cooler outlet hole 34 into which oil discharged from the cooler 30 flows is opened.

  The oil discharged from the oil pump 8 reaches the outlet 27 through the oil filter 29 through the oil passage 23 built in the oil pan 2, and the oil passage 23 is formed by drilling. This state is schematically shown in FIG.

  In FIG. 5, white circles indicate a state of opening to the outside of the oil filter 29, and black circles indicate a crossing portion of the passage. The oil passage 23 is composed of a large number of straight portions, and the straight portions are processed into the oil pan 2 from the outside.

Specifically, the oil passage 23 communicated with the vertically long first portion 23a constituting the discharge port 21 of the oil pump 8, the vertically oriented second portion 23b communicating with the first portion 23a, and the second portion 23b. The horizontal third portion 23c communicated with the third portion 23c and the vertically long fourth portion 23d constituting the filter inlet hole 31, and the vertically long fifth portion 23e and fifth portion 23e constituting the filter outlet hole 32. The horizontally long sixth portion 23f and the sixth portion 23f communicated with the vertically long seventh portion 23g constituting the cooler inlet hole 33, and the vertically long eighth portion 23h and eighth portion 23h constituting the cooler outlet hole 34. A horizontally long ninth portion 23i, a vertically long tenth portion 23j communicating with the ninth portion 23i, and a vertically long eleventh portion 23k communicating with the tenth portion 23j and having an upper end serving as an outlet 27 are configured. That. In this case, the vertical direction refers to the axial direction (front-rear direction) of the crankshaft 7, and the horizontal direction refers to a substantially horizontal direction (left-right direction) orthogonal to the crankshaft 7.

  The second portion 23b, the third portion 23c, the sixth portion 23f, the ninth portion 23i, the tenth portion 23j, and the eleventh portion 23k include an extension portion 37 that is opened to the outside of the oil pan 2 for drilling. Is added, and the extension 37 is closed with a plug (not shown). The second portion 23b and the tenth portion 23j are formed on a protrusion 38 provided on the bottom of the oil pan 2, and therefore both have a tunnel structure.

(3) Summary / Others As described above, since the oil pump 8 is fixed to the ladder frame 5 of the cylinder block 1, the oil pan 2 can be removed and attached regardless of the oil pump 8. That is, the oil pan 2 can be easily removed and attached without requiring the troublesome work of removing the chain 14 one by one. Therefore, the oil pan 2 can be easily attached or replaced.

  In addition, since the oil pump 8 can be attached and removed with the oil pan 2 removed, the chain 14 can be easily attached and detached. Therefore, the work of assembling the engine and maintaining and exchanging the oil pump 8 is also reduced. Can be reduced.

  Further, since the oil passage 23 and the main gallery automatically communicate with each other when the oil pan 2 is attached, the connection operation of the oil passage is unnecessary, and the workability is excellent also in this aspect. Further, even if there is an installation error in the vertical direction of the oil pan 2 or a processing error in the vertical direction of the oil pan 2, the error is absorbed by the O-ring 25, and therefore the seal between the oil pump 8 and the oil passage 23. Sexual problems do not arise.

  Further, since the outlet 27 of the oil passage 23 is disposed inside the oil pan 2, not only can the sealing performance between the oil pan 2 and the ladder frame 5 be securely secured, but also the outlet 27 of the oil passage and the main Even if some oil leaks from the gallery 28, the leaked oil is simply transferred to the oil pan 2 as it is, so there is no problem of engine dirt or increase in oil consumption.

  Further, when the cylindrical boss 26 in which the outlet 27 of the oil passage 23 is formed is provided, the cylindrical boss portion 23 also functions as a reinforcing column that connects the oil pan 2 and the ladder frame 5. It can also contribute to improved mounting strength.

  If the oil filter 29 and the oil cooler 30 are arranged on one end surface of the oil pan 2 as in the embodiment, the oil pan 2 can be effectively used to make the engine compact. In particular, since the oil filter 29 and the oil cooler 30 are located below the front cover, the protrusion to the outside of the front cover can be reduced, which can further contribute to downsizing.

  The present invention can be embodied in various ways other than the above-described embodiment. For example, the connection structure between the discharge port 21 of the oil pump and the inlet 22 of the oil passage can be a structure that fits together. Moreover, the structure of the oil pump 8 can be changed as needed. The oil pump can be fixed to the inner surface of the ladder frame.

  The present invention can actually be embodied in an internal combustion engine. Therefore, it can be used industrially.

1 a cylinder block 2 of the oil pan 3 cylinder block body 5 ladder frame 7 crankshaft 8 oil pump 9 pump housing 11 the pump chamber 12 the rotor 13 rotates shaft 13 'sprocket 14 chain 18 suction port 19 the suction tube 21 discharge port 22 of the oil passage Inlet 23 Oil passage 25 O-ring as an example of elastic sealing material 26 Cylindrical boss 27 Oil passage outlet 28 Main gallery 29 Oil filter 30 Oil cooler

Claims (2)

A cylinder block and an oil pan fixed to the lower surface of the cylinder block, and an oil pump fixed to the cylinder block and exposed to the inside of the oil pan.
While the oil pump has a suction port for sucking oil accumulated in the oil pan and a discharge port for pressurizing and discharging the oil,
The oil pan is formed with an oil passage communicating with the discharge port of the oil pump, and the inlet of the oil passage and the discharge port of the oil pump communicate with each other when the oil pan is fixed to the cylinder block. a disposed have that configured,
The oil pump is disposed immediately below one end of the crankshaft, and is fixed to the lower surface of a ladder frame that rotatably holds the crankshaft from below at one end of the cylinder block.
Furthermore, the suction cylinder connected to the suction port is disposed inside the oil pan as compared with the oil pump as seen from the axial direction of the crankshaft.
Internal combustion engine. A cylinder block and an oil pan fixed to the lower surface of the cylinder block, and an oil pump fixed to the cylinder block and exposed to the inside of the oil pan.
While the oil pump has a suction port for sucking oil accumulated in the oil pan and a discharge port for pressurizing and discharging the oil,
The oil pan is formed with an oil passage communicating with the discharge port of the oil pump, and the inlet of the oil passage and the discharge port of the oil pump communicate with each other when the oil pan is fixed to the cylinder block. The configuration is arranged as follows,
The oil pump discharge port is opened downward, the oil passage inlet of the oil pan is opened upward, and the oil passage outlet is located inside the inner circumference of the oil pan. When the oil pan is fixed to the cylinder block, the outlet of the oil passage communicates with the main gallery of the cylinder block, and the inlet of the oil passage and the discharge port of the oil pump are connected to each other. To communicate,
The internal combustion engine.

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