JPH0413368Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a new oil pan structure, and in particular
An oil pan is formed from a vibration-damping steel plate made by laminating three or more steel plates with a resin layer interposed between them, and the vibration-damping steel plate prevents damage to the oil pan and blocks oil from entering between the laminations of the vibration-damping steel plates. This invention relates to an oil pan drain structure that prevents separation of oil pans.

[Prior Art] Oil pans generally used in internal combustion engines include
Vibrations from the internal combustion engine are directly transmitted, causing the stored oil to vibrate violently and become a source of noise.

Therefore, an oil pan structure made of vibration-damping steel plates as shown in FIGS. 11 to 15 has been proposed.

As shown in Fig. 12, this oil pan structure consists of a damping steel plate with a resin layer interposed between steel plates 1 and 2 having different natural frequencies, and is pressed into a predetermined shape with oil as shown in Fig. 11. Bread 3 is being formed.

In addition, after the oil pan 3 is formed, in order to drain the oil stored in the oil pan 3,
As shown in FIGS. 11 and 12, a through hole 4 is formed by opening the bottom thereof. A drain sheet 5 is inserted into the through hole 4, and a drain bolt 11 is screwed into the drain sheet 5 by opening its axis.

The drain sheet 5 is formed as shown in FIGS. 12 to 14.

As shown in the figure, the drain seat 5 includes a drain pipe 6 formed into a tubular shape, a flange portion 7 formed by enlarging the outer periphery of the bottom portion and seated on the inner surface of the oil pan 2, and the flange portion 7. It is integrally formed of a projection part 8 formed on the lower surface of the drain pipe 6 and a female thread part 30a formed on the inner circumferential surface of the drain pipe 6 and into which the drain bolt 11 is screwed.

At this time, in order to weld the drain sheet 5 to the oil pan 3, welded spot portions 9 are formed in the oil pan 3 for supplying electricity to the steel plates 1 and 2.

Therefore, the drain sheet 5 is seated concentrically with the through hole 4 of the oil pan 3, and the projection part 8 is projection welded (spot welded) to attach the drain sheet 5 to the oil pan 3. will be integrated.

Therefore, as shown in FIG. 15, the flange portion 7 of the drain sheet 5 placed on the oil pan 3 placed on the jig 10 in alignment with the through hole 4 is pressurized evenly, and the projection is carried out. By performing spot welding or the like, the drain sheet 5 can be fixed to the orpan 3 without being inclined.

However, although the oil pan 3 formed as described above effectively damps vibrations propagated from the internal combustion engine and reduces noise, the vibration stress is caused by the welded parts (projection parts 8, spots). Since the load is concentrated on the oil pan 3), a crack C occurs as shown in FIG.
This caused the oil stored inside the tank to leak.

As a method of fixing the drain sheet 5 to the oil pan 3 to solve this drawback, Utility Model No. 56-138137
The publication introduces a mounting structure for cylindrical members such as connectors. This proposal includes providing a through hole 4 in the mounting member 15 as shown in FIG. Anti-rotation protrusion 1 made of thermoplastic resin
7 is integrally provided, and the mounting member 15 is provided with a through hole 4a through which the rotation prevention protrusion 17 is penetrated,
The anti-rotation protrusion protruding from the mounting member 15 is deformed by heating, but as mentioned above, it is inappropriate in terms of strength and weather resistance to be applied to a member subject to high vibrations such as the oil pan 3. Also, due to the torsional torque when tightening or loosening the drain bolt 11, etc., the rotation prevention protrusion 17 may be torsionally broken, and the drain seat 5 may come off from the oil pan 3, causing oil to leak. There is.

Therefore, as shown in Fig. 18, the oil pan 3
A male thread 18 is formed on the outer periphery of the drain pipe 6 of the drain sheet 5 that is inserted into the through hole 4, and a sealing member such as an O-ring is formed in the annular packing groove 19 formed in the flange portion 7 on the oil pan 3 side. 20 are fitted to form the drain seat 5, and a lock nut 21 is screwed into the male threaded portion 18 inserted into the through hole 4 and projected into the oil pan 3 to be fixed therein.

[Problems to be solved by the invention] However, the above proposal still has the following problems.

(1) When attaching the drain bolt to the drain seat 5, when tightening it, the drain seat 5 and the drain bolt 11 rotate together, so the lock nut 21 is relatively rotated to the loosened side. Oil in the oil pan 3 leaks from the hole 4.

(2) When tightening the drain bolt 11, the drain bolt 11 and the drain seat 5 rotate together, which damages the seal member 20.

(3) As the lock nut 21 becomes larger and weighs more, depending on the tightening torque, the surface pressure of the damping steel plate against the oil pan 3 increases, causing the oil pan 3 to deform.

(4) After tightening the lock nut 21 and the drain seat 5 under tightening torque control, when the drain bolt 11 is tightened, the lock nut 21 can be tightened by tightening the drain bolt 11. The drain sheet 5 is turned to the tight side (3) and the oil pan 3 is similarly deformed.

[Purpose of the invention] This invention was devised to solve the above-mentioned problems.The purpose of the invention is to prevent damage to the oil pan from occurring in the through hole for draining the oil pan formed from a damping steel plate. To provide a drain structure for an oil pan in which a drain sheet is securely fixed without any problems.

[Summary of the invention] In order to achieve the above object, the invention forms a drain pipe and a rotation prevention protrusion on one of two drain sheets installed inside and outside the oil pan made of vibration damping steel plate,
A through-hole is formed in the oil pan through which the drain pipe and the anti-rotation protrusion are inserted, and the two sheets are fixed to the oil pan by a fixing means that fixes both sheets. It prevents rotation and securely and easily fixes it.

[Embodiment] Hereinafter, a preferred embodiment of the oil pan drain structure of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, 3 is, for example, a steel plate 1, 2.
This is an oil pan made of vibration-damping steel plates with a resin layer interposed between them. As shown in FIG. 6, this oil pan 3 is depressed by a press or the like and formed into a substantially box shape, and the bottom plate 3a of the oil pan 3 includes:
One of the through holes 13 through which a drain pipe (described later) is inserted at an appropriate position, and a detent protrusion (described later) which is disposed around the one through hole 13 at a predetermined interval in the radial direction from the through hole 13 is inserted. The other through hole 14 is opened.

2 to 4 show two drain sheets inserted into the through holes 13 and 14.

As shown in FIG. 2, one drain sheet 5a
A plurality of pin-shaped anti-rotation protrusions 17 are integrally disposed on one side surface 23a of, for example, an annular member 22a having an opening 21a in the axial center thereof and extending in the circumferential direction. The anti-rotation protrusion 1
7 has a female threaded portion 25 formed by drilling the shaft core.

The other drain sheet 5b has an opening 2 in its axial center.
A drain pipe 6 is formed with an annular member 22b having a diameter of 1b, and has an inner diameter approximately equal to that of the opening 21b.
However, one side 23b of the other drain sheet 5b is
It is integrally joined coaxially with the opening 21b. Further, the annular member 22b is provided with a plurality of engagement holes 26 along the circumferential direction of one side surface 23b thereof, into which the detent protrusions 17 of the one drain sheet 5a are inserted, and on the axis of the annular member 22b. A counterbore portion 28 having a predetermined inner diameter and a predetermined depth is formed on the other side surface 27, as shown in FIG. Furthermore, the opening of the other drain sheet 5b is provided with an engaging female threaded portion 3 that engages the drain bolt 11 shown in FIG.
0 is formed.

Two drain sheets 5 formed in this way
a and 5b are integrally fixed to the oil pan 3 as shown in FIG.

As shown in the figure, the anti-rotation protrusion 17 of one drain sheet 5a is inserted into the through hole 14 of the other oil pan 3 from the outside, and the anti-rotation protrusion 17 of the drain sheet 5a of the oil pan 3 is inserted into the through hole 13 of the other oil pan 3. After inserting the drain pipe 6 of the drain sheet 5b and engaging the engagement hole 26 formed in the annular member 22a with the detent projection 17, as shown in FIG. For example, as shown in FIG. 5, a cross-recessed round countersunk machine screw 32 is inserted into the female threaded portion 25 and is seated in the counterbore portion 28 of the other drain sheet 5b.
is screwed in, and the two drain sheets 5a and 5b are fixed to the oil pan 3.

In this embodiment, the female threaded portion 25 and the cross-recessed round countersunk screw 32 form the fixing means 12.

In addition, the engagement screw portion 3 of the other drain sheet 5b
0, a drain bolt 11 is removably fitted, and a flanged hexagonal bolt head 1 is provided on the seat surface of the drain bolt 22 to enlarge the contact area with the annular member 22a of one of the drain sheets 5a.
1a, and the seat surface of the head 11a is provided with an annular packing groove 19 for accommodating a sealing member 20 such as an O-ring. Further, an annular packing groove 19a for accommodating the seal member 20 is provided on the oil pan 3 side of the annular member 22b of the other drain sheet 5b.

In addition, with the two drain sheets 5a and 5b fixed to the oil pan 3, the top end surface of the drain pipe 6, the bolt head 11a, and the cross-recessed round countersunk screw 32 are attached.
Spaces s ₁ and s ₂ forming an appropriate tightening margin 3 are formed between the seat surface of the seat and the end surface of the anti-rotation protrusion 17, and the drain seats 5a and 5b are properly tightened and fixed to the oil pan 3. making it possible to do so. Further, between the seat surface of the machine screw 32 and the counterbore portion 28, for example, an epoxy-based coating material is filled to ensure sealing performance.

Therefore, the two drain sheets 5a and 5b are prevented from rotating and securely fixed to the oil pan 3 by the fixing means 12.

Next, other embodiments of the present invention are shown in FIGS. 7 to 10.
This will be explained based on the diagram.

FIG. 7 shows an example in which the anti-rotation protrusion 17 is formed to engage and integrate with one of the drain sheets 5a as a separate member.

As shown in the figure, the female threaded portion 25 is formed on the shaft core, and a seat portion 33 is formed at the lower end, and the seat portion 33 has a protrusion portion 34 that protrudes in, for example, a chevron shape.
are radially and integrally arranged at predetermined intervals in the circumferential direction, thereby forming the detent projections 17a.

On the other hand, in order to integrate the anti-rotation projections 17a into one of the drain sheets 5a, the anti-rotation projections 17a are inserted at predetermined intervals in the circumferential direction of the annular portion 22a of the drain sheet 5a, as shown in FIG. A fitting hole 35 is formed in the seat portion 3.
3 and a protrusion 34 provided thereon,
The locking groove 36 has a shape that prevents the seat portion 33 from rotating.
is recessed in one side of the annular member 22a and is formed concentrically with the fitting hole 35.

FIG. 9 shows how the other drain seat 5b and anti-rotation protrusion 17a formed on the separate member are connected to the oil pan 3.
It is shown attached to the

FIG. 10 shows an example in which the cross-recessed countersunk screw 32 explained in FIG. gender will be preserved.

[Effects of the Invention] As detailed above, the present invention provides the following excellent effects.

(1) A through hole is provided in the bottom of the oil pan made of a damping steel plate to drain oil stored in the oil pan, and two drain sheets are installed in the through hole to prevent rotation with respect to the oil pan. Since the structure is configured such that the oil pan can be fixed with screws, it is possible to eliminate a portion where vibrations applied to the oil pan after installation are concentrated, thereby providing a highly durable and reliable oil pan drain structure.

(2) The oil pan can be manufactured easily by eliminating the welded structure.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a preferred embodiment of the oil pan drain structure of the present invention, Figs. 2 to 4 are schematic perspective views showing two drain sheets, and Fig. 5 is a cross-recessed countersunk machine screw. 6 is a schematic perspective view showing the oil pan, FIG. 7 is a perspective view showing a locking projection as a separate member, and FIG. 8 is an annular member to which the locking projection shown in FIG. 7 is locked. 9 and 10 are schematic sectional views showing other embodiments,
FIG. 11 is a schematic view showing an oil pan formed of a damping steel plate, and FIGS. 12 to 18 are schematic views showing conventional examples. In the figure, 3 is an oil pan, 4, 13, 14 are through holes, 5, 5a, 5b are drain seats, 11 is a drain bolt, 17 is a rotation prevention projection, and 12 is a fixing means.

Claims (1)

[Scope of utility model registration request] A drain pipe and a rotation prevention protrusion are formed on one of two drain sheets that are installed inside and outside of an oil pan made of a damping steel plate, and a through hole is formed in the oil pan through which the drain pipe and rotation prevention projection are inserted. Also, an oil pan drain structure characterized in that both of the above-mentioned sheets are fixed to the oil pan by a fixing means.