JP2021148069A - Drain structure - Google Patents

Abstract

To improve seal performance while effectively suppressing a drip of liquid which is discharged from a drain hole.SOLUTION: A drain structure 20 of a tank 10 for storing liquid comprises: a drain hole 21 formed at a wall part 13 of the tank 10 so as to penetrate it; an outside cylindrical part 24 for surrounding an opening peripheral edge of the drain hole 21, and protruding to the outside of a wall face of the tank 10; a fastened part 22A arranged at an internal peripheral face of an inside cylindrical part 22 protruding to the inside of the tank 10 from the drain hole 21 ; an annular seal member 26 having a penetration hole 26A for allowing the insertion of the outside cylindrical part 24, and formed longer than a protrusion length of the outside cylindrical part 24 in an axial length; and a plug member 27 having a fastening part 27B fastened to the fastened part 22A, and blocking the drain hole 21 by being seated on the annular seal member 26.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to a drain structure, and more particularly to a technique suitable for a drain structure of an oil pan.

For example, in Patent Documents 1 and 2, an inner tubular portion is formed in the bottom of an oil pan for storing oil through a drain hole for discharging oil and protrudes inward of the oil pan from the peripheral edge of the opening of the drain hole. Disclosed is a drain structure in which a drain hole is closed by screwing a male threaded portion of a drain plug from the outside of an oil pan to a female threaded portion formed on the inner peripheral surface of the inner tubular portion. ..

Japanese Unexamined Patent Publication No. 2002-054416 Japanese Unexamined Patent Publication No. 59-019798

In the above drain structure, when the drain plug is removed and the oil is drained from the drain hole, a part of the oil released from the drain hole flows along the outer wall surface of the oil pan, so that the oil flows downward. May hang down.

In order to prevent such sagging, the bottom wall portion of the oil pan is subjected to burring processing as in the structure described in Document 2 above, so that the peripheral edge of the opening of the drain hole is outside the outer wall surface of the oil pan. It is preferable to project it. However, if the peripheral edge of the opening of the drain hole is projected, the flange portion of the drain plug interferes with the peripheral edge of the opening of the drain hole when the drain plug is screwed, which may lead to a decrease in sealing property.

The technique of the present disclosure has been made in view of the above circumstances, and an object of the present invention is to improve the sealing property while effectively suppressing the dripping of oil (liquid) discharged from the drain hole.

The technique of the present disclosure is a drain structure of a tank for storing a liquid, and surrounds a drain hole formed through the wall portion of the tank and an opening peripheral edge of the drain hole, and is outside the wall surface of the tank. An outer tubular portion that protrudes, an inner peripheral surface of the inner tubular portion that protrudes from the drain hole to the inside of the tank, or a fastened portion provided on either the inner peripheral surface of the outer tubular portion. It is fastened to the fastened portion with an annular seal member having a through hole into which the outer tubular portion is inserted and having an axial length longer than the protruding length of the outer tubular portion from the wall surface. It is characterized by having a fastening portion and a plug member that sits on the annular seal member and closes the drain hole.

Further, the portion to be fastened is a female screw portion, and the plug member is a drain plug having a male screw portion as the fastening portion screwed with the female screw portion and a flange portion seated on the annular seal member. Is preferable.

Further, it is preferable that the outer cylindrical portion is integrally formed with the wall portion of the tank through which the drain hole penetrates.

Further, it is preferable that the tank is an oil pan.

According to the technique of the present disclosure, it is possible to improve the sealing property while effectively suppressing the dripping of the oil (liquid) discharged from the drain hole.

It is a schematic vertical sectional view which shows the oil pan which concerns on this embodiment. It is a schematic disassembled perspective view which shows the drain structure which concerns on this embodiment. It is a typical vertical cross section which shows the drain structure which concerns on this embodiment. It is a schematic vertical cross section which shows the drain structure which concerns on other embodiment.

Hereinafter, the drain structure according to the present embodiment will be described with reference to the attached drawings. The same parts have the same reference numerals, and their names and functions are also the same. Therefore, detailed explanations about them will not be repeated.

[overall structure]
FIG. 1 is a schematic vertical sectional view showing an oil pan 10 according to the present embodiment.

As shown in FIG. 1, the oil pan 10 (an example of the tank of the present disclosure) is provided, for example, in the lower part of the crankcase C of the engine E, and the engine oil supplied to each lubricating element of the engine E (hereinafter referred to as engine oil). , Simply store oil). The oil pan 10 may be an oil pan for storing oil in a transmission, a clutch device, a differential gear device, or the like. Further, the application of the present disclosure is not limited to the oil pan, and may be a radiator lower tank or the like for storing cooling water.

The oil pan 10 includes a bottom wall portion 11, a side wall portion 12 extending upward from the peripheral edge of the bottom wall portion 11, and an inclined wall portion 13 that obliquely connects the bottom wall portion 11 and the side wall portion 12 and is inclined. A flange plate portion 14 projecting outward from the upper end of the side wall portion 12 is provided.

The flange plate portion 14 is provided with a plurality of bolt insertion holes. The oil pan 10 is attached to the engine E by inserting the bolt 15 into the bolt insertion hole and screwing the bolt 15 into the female screw hole of the crankcase C.

The drain structure 20 of the present disclosure is provided on the inclined wall portion 13 of the oil pan 10. The drain structure 20 may be provided on the bottom wall portion 11 or the side wall portion 12, but if the drain structure 20 is provided on the inclined wall portion 13, the amount of protrusion downward can be increased as compared with the structure provided on the bottom wall portion 11. It can be suppressed and the minimum ground clearance can be effectively secured. Further, if the drain structure 20 is provided on the inclined wall portion 13, the amount of protrusion to the side can be suppressed as compared with the structure provided on the side wall portion 12, and the degree of freedom in the peripheral layout can be secured.

Hereinafter, the details of the drain structure 20 according to the present embodiment will be described.

[Drain structure]
FIG. 2 is a schematic exploded perspective view showing the drain structure 20 according to the present embodiment, and FIG. 3 is a schematic vertical cross section showing the drain structure 20 according to the present embodiment.

As shown in FIGS. 2 and 3, the drain structure 20 includes a drain hole 21, an inner cylindrical portion 22, an outer tubular portion 24, an annular seal member 26, and a drain plug 27 (an example of a plug member). And have.

The drain hole 21 is a circular hole penetrating the inclined wall portion 13 of the oil pan 10, and allows oil to be discharged from the inside of the oil pan 10. The hole diameter of the drain hole 21 may be larger than the outer diameter of the shaft portion 27A of the drain plug 27, which will be described later.

The inner tubular portion 22 is formed in a substantially cylindrical shape surrounding the opening peripheral edge of the drain hole 21, and is arranged concentrically with the drain hole 21. The inner cylindrical portion 22 projects to the inside of the oil pan 10 by fixing the base end portion 23 (FIG. 3) to the inner peripheral surface of the inclined wall portion 13 by welding or the like.

As shown in FIG. 3, an oil discharge groove 23A communicating with the drain hole 21 is recessed in the base end portion 23 of the inner tubular portion 22. The oil discharge groove 23A functions to send the oil remaining on the bottom side of the oil pan 10 to the drain hole 21 when the oil is discharged. Further, on the inner peripheral surface of the inner cylindrical portion 22, a female screw portion 22A (fastened portion) to be screwed with the male screw portion 27B (fastening portion) of the drain plug 27, which will be described later, is provided.

The outer tubular portion 24 is formed in a substantially cylindrical shape surrounding the opening peripheral edge of the drain hole 21, and projects outward from the outer wall surface of the inclined wall portion 13. The outer cylindrical portion 24 is preferably formed as a protruding hole integrated with the drain hole 21 by subjecting the inclined wall portion 13 to a burring process from the inside. When the outer cylindrical portion 24 is integrally formed with the drain hole 21 by burring in this way, the base end side of the outer tubular portion 24 and the opening peripheral edge of the drain hole 21 are connected by a smooth curved surface portion 25. become.

The annular seal member 26 is formed of, for example, copper or the like in a substantially annular shape, and has a through hole 26A having a diameter larger than the outer diameter of the outer cylindrical portion 24. More specifically, the hole diameter of the through hole 26A is formed to be larger than the outer diameter of the curved outer surface of the curved surface portion 25, and when the drain plug 27 described later is screwed, the annular seal member 26 is formed on the inclined wall portion. It is configured so that it can be reliably seated on the outer wall surface of 13.

Further, the axial length (thickness) of the annular seal member 26 is formed to be longer than the protruding length (height) of the outer tubular portion 24 from the inclined wall portion 13. That is, when the drain plug 27 is screwed, the annular seal member 26 is sandwiched between the outer wall surface of the inclined wall portion 13 and the flange portion 29 of the drain plug 27 in a pressure-welded state. As a result, it becomes possible to prevent interference between the protruding end edge of the outer tubular portion 24 and the flange portion 29, and it is possible to reliably improve the sealing property.

The drain plug 27 has a substantially hexagonal columnar head portion 28, a flange portion 29 having a diameter larger than that of the head portion 28 and the through hole 26A of the annular seal member 26, and a flange portion 29 protruding from the flange portion 29 to the opposite side of the head portion 28. It is provided with a shaft portion 27A. On the outer peripheral surface of the shaft portion 27A, a male screw portion 27B to be screwed with the female screw portion 22A is provided.

That is, when the male threaded portion 27B of the drain plug 27 is screwed into the female threaded portion 22A of the inner cylindrical portion 22, the annular sealing member 26 is pressed against the outer wall surface of the inclined wall portion 13 by the flange portion 29 to form the drain hole 21. It can be closed.

According to the drain structure 20 of the present embodiment described in detail above, an outer cylindrical portion 24 projecting outward from the outer wall surface of the inclined wall portion 13 is provided on the peripheral edge of the opening of the drain hole 21. As a result, when the drain plug 27 is removed and the oil is drained, it becomes possible to prevent the oil discharged from the drain hole 21 from flowing along the outer wall surface of the inclined wall portion 13 and the bottom wall portion 11, and the oil can be prevented from flowing. It is possible to effectively prevent the oil from dripping downward.

Further, by forming the axial length of the annular seal member 26 longer than the protruding length of the outer tubular portion 24, interference between the flange portion 29 of the drain plug 27 and the outer tubular portion 24 can be effectively prevented. It is configured as follows. As a result, it becomes possible to effectively prevent a gap from being generated between the annular seal member 26 and the flange portion 29, or between the annular seal member 26 and the outer wall surface of the inclined wall portion 13, and the sealing property can be improved. It will be possible to improve with certainty.

[others]
The present disclosure is not limited to the above-described embodiment, and can be appropriately modified and implemented without departing from the spirit of the present disclosure.

For example, as shown in FIG. 4, the outer cylindrical portion 24 is formed of a member separate from the oil pan 10, and the peripheral edge on the base end side of the outer tubular portion 24 is joined to the oil pan 10 by welding or the like. You may. In this case as well, the same effects as those in the above embodiment can be obtained. Further, although the female screw portion 22A has been described as being provided on the inner cylindrical portion 22, the female screw portion 22A may be provided on the inner peripheral surface of the outer tubular portion 24. Further, the fastening structure between the drain plug 27 and the inner cylindrical portion 22 is not limited to the female screw portion 22A and the male screw portion 27B, and may be another fastening structure.

10 Oil pan (tank)
11 Bottom wall (wall)
12 Side wall (wall)
13 Inclined wall (wall)
20 Drain structure 21 Drain hole 22 Inner cylindrical part 22A Female thread part (fastened part)
24 Outer tubular part 26 Circular seal member 26A Through hole 27 Drain plug (plug member)
27A Shaft part 27B Male thread part (fastening part)
28 Head part 29 Flange part

Claims (4)

It is a drain structure of a tank that stores liquid,
A drain hole formed through the wall of the tank and
An outer cylindrical portion that surrounds the opening peripheral edge of the drain hole and projects outward from the wall surface of the tank.
A fastened portion provided on either the inner peripheral surface of the inner cylindrical portion protruding from the drain hole to the inside of the tank or the inner peripheral surface of the outer tubular portion.
An annular seal member having a through hole into which the outer tubular portion is inserted and having an axial length longer than the protrusion length of the outer tubular portion from the wall surface.
A drain structure comprising a fastening portion to be fastened to the fastened portion, and a plug member that is seated on the annular seal member and closes the drain hole. Further, the fastened portion is a female threaded portion, and the plug member is a drain plug having a male threaded portion as the fastening portion screwed with the female threaded portion and a flange portion seated on the annular seal member. Item 1. The drain structure according to item 1. The drain structure according to claim 1 or 2, wherein the outer cylindrical portion is integrally formed with a wall portion of the tank through which the drain hole penetrates. The drain structure according to any one of claims 1 to 3, wherein the tank is an oil pan.

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