JP5979360B2 - Engine oil pan structure - Google Patents

Description

  The present invention relates to a double-structured oil pan having an inner oil pan and an outer oil pan.

2. Description of the Related Art As an oil pan provided at the lower part of an engine and storing lubricating oil, a double-structured oil pan configured with an inner oil pan installed in an outer oil pan is widely known.
In the engine having the oil pan having the double structure, the first storage chamber capable of storing the lubricating oil in the inner oil pan and the second storage capable of storing the lubricating oil between the inner oil pan and the outer oil pan. A chamber is formed. Furthermore, the lubricating oil is sucked out from the first storage chamber through the strainer, supplied to a portion requiring lubrication in the engine, and returned to the first storage chamber to be circulated. The chamber and the second storage chamber can communicate with each other via a thermo valve. When the temperature is low, such as during warm-up operation, the thermo valve is closed, and only the lubricating oil in the first storage chamber is circulated to increase the temperature of the lubricating oil quickly. At high temperatures, the thermo valve is open. Thus, the first storage chamber and the second storage chamber are communicated with each other, and the amount of lubricating oil that can be circulated is increased to prevent excessive temperature rise of the lubricating oil (Patent Document 1).

  Incidentally, a drain hole is provided at the bottom of the oil pan in order to draw out the lubricating oil from the oil pan when the lubricating oil is replaced, and the drain hole is closed by a drain plug. As described above, in the oil pan having the double structure, when the oil is drained from the oil pan, the lubricating oil not only in the outer oil pan but also in the inner oil pan (first storage chamber) can be discharged. Is required.

Therefore, for example, in Patent Document 1, a small-diameter drain hole is provided in the bottom wall of the inner oil pan.
In addition, the inner oil pan and the outer oil pan are each provided with a drain hole coaxially, and the drain plug is constituted by an inner plug that closes the drain hole of the inner oil pan and an outer plug that closes the drain hole of the outer oil pan. However, a method has also been considered in which both the inner plug and the outer plug are removed at the time of oil removal so that the lubricating oil can be discharged from both the inner oil pan and the outer oil pan.

JP 2006-207521 A

However, as in Patent Document 1, if the drain hole is simply provided in the inner oil pan, the lubricating oil always circulates between the inner oil pan and the outer oil pan, and the inner oil pan is warmed up during the warm-up operation. There is a problem that the temperature rise of the lubricating oil in the pan is hindered.
In addition, when the drain plug is constituted by the inner plug and the outer plug as described above, the structure of the drain plug is complicated and the cost is increased, and it becomes difficult to remove the drain plug, particularly the inner plug. There is a problem that man-hours are increased at the time of unplugging.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to easily remove oil from the oil pan with a simple structure and to suppress heat transfer between the inner oil pan and the outer oil pan during warm-up operation. It is to provide an oil pan structure for an engine.

  In order to achieve the above-mentioned object, the invention according to claim 1 is the first oil tank configured by installing the inner oil pan on the bottom wall of the outer oil pan, and storing the lubricating oil in the inner oil pan. It has a storage chamber and a second storage chamber for storing lubricating oil between the outer oil pan and the inner oil pan, and the first storage chamber and the second storage when the lubricating oil is below a predetermined temperature. A restriction means for restricting the flow of the lubricating oil between the first and second storage chambers, sucking the lubricating oil stored in one of the first and second storage chambers, An oil pan structure for an engine having a lubricating oil circulation path that is returned to the storage chamber, the opening being open to the second storage chamber between the bottom wall of the outer oil pan and the bottom wall of the inner oil pan With some gaps A communication hole is formed in the bottom wall of the inner oil pan facing the gap, and a communication path is formed to communicate the first storage chamber and the second storage chamber by the opening, the clearance, and the communication hole. The outer oil pan facing the second storage chamber is provided with a drain hole capable of discharging the lubricating oil in the second storage chamber.

According to a second aspect of the present invention, in the first aspect of the present invention, the clearance between the communication passage and the outer oil pan is formed on a part of the bottom wall of the inner oil pan and a protruding portion protruding in a direction away from the bottom wall of the outer oil pan. It is characterized by being formed as a space surrounded by the bottom wall.
According to a third aspect of the present invention, in the first or second aspect, the suction port for sucking the lubricating oil in the first storage chamber is provided in the inner oil pan, and the suction port and the communication hole are separated from each other in the horizontal direction. It is characterized by being arranged.

The invention of claim 4 is Oite to claim 2, the first reservoir chamber and an insertion hole for inserting the second storage chamber provided in the inner oil pan, regulating means closing means for opening and closing the insertion hole The projecting portion is formed between the opening / closing means and the suction port.

  According to the first aspect of the present invention, a communication passage is provided in which a gap is provided between the bottom wall of the outer oil pan and the bottom wall of the inner oil pan to communicate the first storage chamber and the second storage chamber. Since the lubricating oil in the second storage chamber is discharged from the drain hole provided in the outer oil pan, the lubricating oil in the first storage chamber can be easily discharged through the communication path. The entire oil pan can be drained.

  In addition, the communication path that communicates the first storage chamber and the second storage chamber is not simply provided with a hole in the inner oil pan, but the bottom wall of the outer oil pan and the bottom wall of the inner oil pan Between the first storage chamber and the second storage chamber, so that a gap is provided between the first storage chamber and the second storage chamber. Lubricating oil becomes difficult to circulate. Therefore, when the lubricating oil is lower than the predetermined temperature, the restriction means restricts the flow of the lubricating oil between the first storage chamber and the second storage chamber, and the lubricating oil in the first storage chamber and the second Heat transfer with the lubricating oil in the storage chamber is suppressed with a simple configuration. For this reason, the temperature fall of the lubricating oil stored in either the 1st or 2nd storage chamber circulated when lubricating oil is less than predetermined temperature can be suppressed.

  According to the invention of claim 2, the clearance of the communication passage is surrounded by the projecting portion that projects a part of the bottom wall of the inner oil pan away from the bottom wall of the outer oil pan and the bottom wall of the outer oil pan. As a result, the gap between the bottom wall of the outer oil pan and the bottom wall of the inner oil pan can be easily provided without changing the shape of the outer oil pan or increasing the number of parts. Can be formed.

  According to the third aspect of the present invention, the suction port for sucking the lubricating oil in the first storage chamber is provided in the inner oil pan, and the suction port and the communication hole are spaced apart from each other in the horizontal direction. Inhalation of the lubricating oil in the second storage chamber through the passage is suppressed. For this reason, when the lubricating oil is less than a predetermined temperature and the flow of the lubricating oil between the first storage chamber and the second storage chamber is regulated by the regulating means, the temperature of the lubricating oil sucked from the suction port is reduced. It can suppress more reliably.

  According to the invention of claim 4, since the protrusion is formed between the opening / closing means for opening and closing the insertion hole provided in the inner oil pan and the suction port, the lubricating oil becomes a predetermined temperature or more and the insertion hole is formed. When the lubricating oil can be circulated between the first storage chamber and the second storage chamber, the low-temperature lubricating oil that has flowed into the first storage chamber from the second storage chamber is sucked into the suction port. It is hard to be inhaled from. That is, since the lubricating oil that has flowed in from the insertion hole temporarily stagnate before the protruding portion, it is possible to suppress a decrease in lubricating performance due to the low-temperature lubricating oil being sucked from the suction port.

It is a longitudinal cross-sectional view which shows schematic structure of the engine which concerns on this embodiment which employ | adopted the oil pan structure of this invention. It is a top view which shows the structure of the oil pan concerning this embodiment. It is a transverse cross section showing the structure of the oil pan concerning this embodiment. It is a top view which shows the positional relationship of the communicating hole of the inner oil pan which concerns on this embodiment, a strainer, and a thermo valve.

Hereinafter, the present invention will be described based on the embodiment shown in FIGS.
FIG. 1 is a longitudinal sectional view showing a schematic structure of an engine 1 according to the present embodiment that employs an oil pan structure of the present invention.
An oil pan 3 for storing lubricating oil is provided below the cylinder block 2 of the engine 1 according to the present embodiment.

The oil pan 3 is a double-structured oil pan 3 constituted by an outer oil pan 4 and an inner oil pan 5 having an upper portion opened in a substantially rectangular shape.
The inner oil pan 5 is smaller than the outer oil pan 4 and is disposed in the outer oil pan 4 and has a first storage chamber 6 in which lubricating oil can be stored.
The bottom portion of the inner oil pan 5 is placed on the bottom wall 4a of the outer oil pan 4 and is partially connected. The inner oil pan 5 is formed to be smaller than the outer oil pan 4 at the lower portion and the middle portion in the vertical direction, and the upper portion is widened to be approximately the same size as the outer oil pan 4. Therefore, a second storage chamber 7 capable of storing lubricating oil is provided between the outer oil pan 4 and the inner oil pan 5.

  In the inner oil pan 5, a strainer 10 for sucking lubricating oil is installed. The strainer 10 is connected to an oil pump 11 provided in the cylinder block 2 via a pipe 12. Lubricating oil in the inner oil pan 5 is supplied to each lubricating portion such as a valve operating device in the engine 1 by an oil pump 11 that operates in accordance with the operation of the engine 1. After lubricating the lubricating portion, the inner oil pan 5 is lubricated. It falls into 5 and comes back.

The suction port 13 of the strainer 10 is arranged at a position close to the bottom wall 5a of the inner oil pan 5 so that the lubricating oil can be sucked even when the amount of the lubricating oil stored in the inner oil pan 5 decreases. Yes.
In addition, an insertion hole 14 that communicates the first storage chamber 6 and the second storage chamber 7 is provided at the center in the front-rear direction of one side wall 5b that extends in the front-rear direction of the inner oil pan 5. A thermo valve 15 (regulating means, opening / closing means) for opening and closing the hole 14 is provided.

The thermo valve 15 opens and closes based on the temperature of the lubricating oil stored in the first storage chamber 6. Specifically, the thermo valve 15 is closed when the temperature of the lubricating oil is lower than a predetermined temperature (for example, 80 degrees Celsius), that is, when the engine 1 is in a warm-up state, and is opened when the temperature is higher than the predetermined temperature. It is set to be.
FIG. 2 is a top view showing the structure of the oil pan 3 according to this embodiment. FIG. 3 is a cross-sectional view showing the structure of the oil pan 3 according to the present embodiment.

As shown in FIGS. 2 and 3, a drain hole 20 that communicates the second storage chamber 7 in the outer oil pan 4 and the outside is provided in the lower portion of the side wall 4 b of the outer oil pan 4. A drain plug 21 capable of closing the hole 20 is provided.
Furthermore, in this embodiment, the bottom wall 5a of the inner oil pan 5 protrudes upward in a T shape to form a protruding portion 22. The protrusion 22 has a width of about 1 cm and a protrusion height of about several mm. The bottom wall 5a of the inner oil pan 5 and the bottom wall 4a of the outer oil pan 4 are in contact with each other at a portion other than the protruding portion 22, and are connected by spot welding or the like. Accordingly, a T-shaped gap 23 is formed between the bottom wall 5 a of the inner oil pan 5 and the bottom wall 4 a of the outer oil pan 4 in the protruding portion 22.

The protrusion 22 formed on the bottom wall 5a of the inner oil pan 5 has a substantially central portion in the left-right direction of the inner oil pan 5 and a portion 22a extending in the front-rear direction substantially parallel to the side wall 5b on which the thermo valve 15 is disposed, A portion 22b extending from the central portion of the portion 22a in a direction away from the thermo valve 15 (rightward in the figure).
Openings 24 are provided at the ends of the respective portions 22a and 22b of the projecting portion 22 so as to face the second storage chamber.

In addition, a communication hole 25 having a diameter of about 7 mm that communicates the gap 23 in the protrusion 22 and the first storage chamber 6 is formed on the upper surface in the vicinity of the end of the portion 22b extending in the direction away from the thermo valve 15 of the protrusion 22. Is provided. The vertical position of the communication hole 25 is located below the lower end position hb of the drain hole 20 provided in the lower part of the outer oil pan 4.
Therefore, the first storage chamber 6 and the second storage chamber 7 communicate with each other via the communication path 26 including the gap 23, the opening 24, and the communication hole 25. The lubricating oil can flow into the second storage chamber 7 through the communication path 26.

FIG. 4 is a top view showing a positional relationship among the communication hole 25, the strainer 10, and the thermo valve 15 of the inner oil pan 5 according to the present embodiment.
As shown in FIG. 4, the suction port 13 of the strainer 10 includes a communication hole 24 provided in the vicinity of an end of a portion 22 b extending rightward in the drawing from a portion 22 a extending in the front-rear direction of the T-shaped protrusion 22. They are separated from each other in the left-right direction. Further, the suction port 13 is located on the right side in the drawing with respect to the portion 22a extending in the front-rear direction, and the thermo valve 15 for opening and closing the insertion hole 14 is located on the left side in the drawing with respect to the portion 22a extending in the front-rear direction. ing.

With such a configuration, in the present embodiment, the thermo valve 15 is closed during the warm-up operation, and therefore the engine 1 is lubricated using only the lubricating oil in the first storage chamber 6. Therefore, since it is circulated with a relatively small amount of lubricating oil, the lubricating oil can be quickly heated to ensure lubricating performance.
On the other hand, when the oil draining operation for discharging the lubricating oil from the oil pan 3 is performed, the drain plug 21 fastened to the outer oil pan 4 may be removed.

  By removing the drain plug 21, the lubricating oil in the second storage chamber 7 between the inner oil pan 5 and the outer oil pan 4 is discharged. Further, since the first storage chamber 6 and the second storage chamber 7 communicate with each other through the communication passage 26 at the lower portion, the first storage chamber 6 and the second storage chamber 7 are discharged when the lubricating oil in the second storage chamber 7 is discharged. Lubricating oil in the storage chamber 6 is also discharged. Accordingly, by removing the drain plug 21 fastened to the outer oil pan 4, the lubricating oil can be discharged from both the first storage chamber 6 and the second storage chamber 7.

  And since the clearance gap 23 which comprises the communicating path 26 which connects the 1st storage chamber 6 and the 2nd storage chamber 7 is formed in T shape, when providing a hole in the inner oil pan 5 simply In addition to the fact that the path is more complicated than that of the first storage chamber 6 and the second storage chamber 7, the lubricating oil is further reduced. Is difficult to circulate. Accordingly, heat transfer between the lubricating oil in the first storage chamber 6 and the lubricating oil in the second storage chamber 7 is difficult, and the thermo valve 15 is particularly closed during operation of the engine 1. During the warm-up operation, the temperature drop of the lubricating oil in the first storage chamber 6 can be suppressed.

  As described above, in this embodiment, the bottom wall 5a of the inner oil pan 5 is formed in a shape protruding in a T shape so that the gap 23 is easily provided between the inner oil pan 5 and the outer oil pan 4. A communication path 26 can be formed. Further, since the drain plug 21 that closes the drain hole 20 for discharging the lubricating oil only needs to be provided in the outer oil pan 4, the drain plug 21 can have a simple configuration, and has the inner oil pan 5 and the outer oil pan 4. In the oil pan 1 having a double structure, the oil draining operation for discharging the lubricating oil becomes easy. Further, since the protruding height of the protruding portion 22 is formed to be lower than the lower end of the drain hole 20, it is possible to reduce the lubricating oil remaining in the inner oil pan 5 during the oil draining operation.

  The communication hole 25 that communicates the gap 23 with the first storage chamber 6 is provided near the end of the portion 22 b that extends in the direction away from the thermo valve 15 of the protrusion 22, and the bottom wall of the inner oil pan 5. 5a, the suction port 13 of the strainer 10 is located on the side of the portion 22a extending in the front-rear direction of the protrusion 22 from the communication hole 25, and the communication hole 25 and the suction port 13 are separated from each other. Therefore, it is difficult to suck the lubricating oil in the second storage chamber 7 from the suction port 13 of the strainer 10 through the communication passage 26. Accordingly, the low temperature lubricating oil in the second storage chamber 7 is suppressed from being sucked when the thermo valve 15 is in a closed state at a low temperature such as during a warm-up operation, and the lubricating oil is quickly raised in temperature. be able to.

  Further, the suction port 13 of the strainer 10 is positioned to the right of the portion 22a extending in the front-rear direction of the protruding portion 22, and the thermo valve 15 is disposed to the left of the portion 22a extending in the front-rear direction of the protruding portion 22. Therefore, for example, when the thermo valve 15 is opened immediately after the warm-up operation, the low-temperature lubricating oil stored in the second storage chamber 7 is not easily sucked from the suction port 13 immediately. At this time, the low-temperature lubricating oil that has passed through the insertion hole 14 and has flowed into the first storage chamber 6 temporarily stagnate before the projecting portion 22, and the relatively high-temperature lubricating oil in the first storage chamber 6. Since it is sucked from the suction port 13 after being mixed, the lubricating performance can be sufficiently ensured. Further, even if the thermo valve 15 is not sufficiently closed at a low temperature due to a failure or the like, the lubricating oil in the second storage chamber 7 having a higher possibility of a lower temperature than in the first storage chamber 6 is removed. Inhalation is suppressed and lubricating performance can be ensured.

  In addition, this invention is not limited to embodiment mentioned above, You may implement in various changes within the range which does not deviate from the main point of this invention. For example, the shape of the protrusion 22 may be a shape other than a T-shape, and the communication path 26 that connects the first storage chamber 6 and the second storage chamber 7 only needs to be a maze. The present invention can be widely applied to an engine oil pan having a double structure including an inner oil pan and an outer oil pan.

DESCRIPTION OF SYMBOLS 1 Engine 3 Oil pan 4 Outer oil pan 5 Inner oil pan 6 1st storage chamber 7 2nd storage chamber 13 Suction inlet 14 Insertion hole 15 Thermo valve (regulation means, opening / closing means)
20 Drain hole 23 Clearance 24 Opening 25 Communication hole 26 Communication path

Claims (4)

An inner oil pan is installed on the bottom wall of the outer oil pan to form an oil pan, and has a first storage chamber for storing lubricating oil in the inner oil pan, and the outer oil pan, the inner oil pan, A second storage chamber for storing lubricating oil between
A restriction means for restricting the flow of the lubricating oil between the first storage chamber and the second storage chamber when the lubricating oil is lower than a predetermined temperature;
An engine having a circulation path for the lubricating oil that sucks the lubricating oil stored in one of the first and second storage chambers, supplies the lubricating oil to an engine lubrication location, and returns the lubricating oil to the one storage chamber. An oil pan structure,
A gap is provided between the bottom wall of the outer oil pan and the bottom wall of the inner oil pan so as to open to the second storage chamber, and the gap facing the gap is provided. A communication hole is provided in the bottom wall of the inner oil pan, and a communication path that connects the first storage chamber and the second storage chamber is formed by the opening, the gap, and the communication hole.
An engine oil pan structure characterized in that the outer oil pan facing the second storage chamber is provided with a drain hole through which the lubricating oil in the second storage chamber can be discharged.   The gap of the communication passage is a space surrounded by a part of the bottom wall of the inner oil pan and a protruding portion protruding in a direction away from the bottom wall of the outer oil pan and the bottom wall of the outer oil pan. The engine oil pan structure according to claim 1, wherein the engine oil pan structure is formed.   The suction port for sucking lubricating oil in the first storage chamber is provided in the inner oil pan, and the suction port and the communication hole are arranged to be spaced apart from each other in the horizontal direction. Or the oil pan structure of the engine of 2. The inner oil pan is provided with an insertion hole through which the first storage chamber and the second storage chamber are inserted, and the restricting means is an opening / closing means for opening and closing the insertion hole,
The engine oil pan structure according to claim 2 , wherein the protrusion is formed between the opening / closing means and the suction port.

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