JPH0141883Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an engine oil pan mounting structure that prevents oil pan vibration and reduces engine noise.

Generally, an oil pan for storing engine oil is bolted to the lower surface of a skirt formed at the bottom of a cylinder block. By the way, the vibrations of the cylinder block are transmitted to the skirt section and oil pan of the engine, but the skirt section has a large opening at the bottom and is therefore prone to vibrations. As shown in Japanese Patent No. 54-61910, there was a system in which a reinforcing member was tightened and fixed to the lower surface of the skirt with mounting bolts, and then an oil pan was fixed to the lower surface of the skirt. However, in this conventional device, the oil pan was attached with a separate bolt from the above-mentioned attachment bolt for the reinforcing member, which resulted in problems such as an increase in the number of bolts and a complicated assembly process. In order to solve this problem, it is conceivable to attach the reinforcing member and the oil pan to the lower surface of the skirt using a common bolt. However, if you do this, you will need long mounting bolts, so the vibrations of the skirt will be amplified by the long mounting bolts and transmitted to the oil pan, and this amplified vibration will cause the oil pan to connect to the joint surface with the reinforcing member. direction, the vibration of the oil pan becomes louder,
There was a problem that engine noise could not be sufficiently reduced.

This idea was devised in view of the problems of the conventional oil pan, and includes interposing a gasket between the reinforcing member and the oil pan, as well as inserting bolt holes in the reinforcing member into the oil pan through the gasket. forming a protrusion that engages with the reinforcing member, and the protrusion has a tapered shape, that is, a truncated conical shape, and the diameter of the base, that is, the bottom surface of the truncated conical shape, is larger than the dimension of the hole in the reinforcing member. By doing so, it is possible to suppress not only the horizontal vibration of the oil pan but also the vertical vibration, and reduce the vibration of the entire oil pan, with a simple configuration and without impairing the oil seal function. The purpose is to obtain an engine oil pan mounting structure.

An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show a first embodiment of the present invention. In the figures, 1 is a cylinder block, and a skirt part 2 having a rectangular horizontal cross section is formed at the bottom of the cylinder block 1. The skirt portion 2 gradually becomes wider in width (horizontal width in FIG. 1) as it goes downward, and a flange 2a is provided outwardly protruding from the periphery of the opening at its lower end. Note that 2b in the figure is a bearing portion for supporting a crankshaft (not shown). Further, a ladder frame 4, which is a ladder-like reinforcing member, is disposed on the lower surface of the flange 2a of the skirt portion 2 via a gasket 3a.
Furthermore, an oil pan 5 is disposed on the lower surface of the ladder frame 4 via a gasket 3b, with a flange 5a at the periphery of its opening abutting against the ladder frame 4, and the ladder frame 4 and oil pan 5 are connected to a skirt portion. It is fastened and fixed to the flange 2a of No. 2 with bolts 6.

A bolt hole 4a for the mounting bolt 6 is bored in the peripheral edge of the ladder frame 4, and a tapered portion 4b is formed at the bottom of the bolt hole 4a by increasing the diameter of the hole downward. There is. The flange 5a of the oil pan 5 has a bolt hole 5b at its tip, and is formed with a tapered locking protrusion 5c that is inserted into the tapered portion 4b and abuts and locks therewith. The tapered portions 4b engage with each other and serve as a locking means for preventing the ladder frame 4 and oil pan 5 from shifting in the direction of their joint surfaces (directions perpendicular to the plane of the paper in FIG. 3 and left and right directions). Note that 6a is a washer interposed between the head of the bolt 6 and the flange 5a of the oil pan 5.

As described above, according to this embodiment, the flange 5a of the ladder frame 4 and the oil pan 5 are each provided with a locking means to prevent them from shifting in the direction of their joint surfaces, and the flange 5a of the skirt portion 2
Since it is installed by tightening the mounting bolts 6 on the bottom surface of the oil pan 5, the vibration of the oil pan 5 can be reduced, and since separate bolts for mounting the ladder frame 4 are not required, the number of bolts does not increase and the assembly work is simplified. It doesn't have to be complicated.

In addition, a tapered locking protrusion 5c is formed by protruding the peripheral edge of the bolt hole 5b on the flange 5a of the oil pan 5, and this is locked with the taper portion 4b of the ladder frame 4, so that the gasket 3b seals. The rudder frame 4 and oil pan 5 are connected with metal touch in a simple structure while ensuring stability, and in addition to preventing relative movement in the lateral direction, they are also firmly fixed in the vertical direction to prevent oil pan vibration. can be suppressed.

Further, since the gasket 3b is provided between the ladder frame 4 and the oil pan 5, this portion can be reliably sealed. Further, since the oil pan 5 is provided with the locking protrusion 5c, the protrusion can be easily formed using a press.

FIG. 4 shows a second embodiment of the invention. In the figure, the same reference numerals as in FIG. 3 indicate the same parts, and in this embodiment, the adjacent bolt holes 4a of the ladder frame 4
A locking hole 4c is bored in between, and a locking protrusion 5d that can lock into the hole is provided on the flange 5a, thereby serving as a locking means for locking the two together. In addition, the above locking hole 4c
does not need to pass through the ladder frame 4.

The effects of this embodiment are exactly the same as those of the first embodiment.

As described above, according to the engine oil pan mounting structure of the present invention, a gasket is interposed between the reinforcing member and the oil pan, and the bolt holes of the reinforcing member are connected to the oil pan through the gasket. An engaging protrusion is formed, and the protrusion has a tapered shape, that is, a truncated conical shape, and the diameter of its base, that is, the bottom surface of the truncated conical shape, is configured to be larger than the dimension of the hole in the reinforcing member. Therefore, with a simple configuration, it is possible to suppress not only the horizontal vibration of the oil pan but also the vertical vibration without impairing the oil seal function, thereby reducing the vibration of the entire oil pan.

[Brief explanation of the drawing]

1 to 3 show an oil pan mounting structure for an engine according to a first embodiment of the present invention.
The figure is a cross-sectional side view, Figure 2 is an exploded perspective view,
Figure 3 is an enlarged cross-sectional view, and Figure 4 is the second diagram of the present invention.
FIG. 1...Cylinder block, 2...Skirt part,
4... Reinforcement member (ladder frame), 5... Oil pan, 4b, 5C... Locking means (tapered part, locking projection), 4c, 5d... Locking means (locking hole, locking projection) .

Claims (1)

[Claim for Utility Model Registration] A ladder-shaped reinforcing member disposed on the lower surface of the skirt and an oil pan attached to the lower surface of the reinforcing member are attached to the skirt portion formed at the lower part of the cylinder block by bolts. In the co-tightened engine oil pan mounting structure, a gasket is interposed between the reinforcing member and the oil pan, and a protrusion is provided on the oil pan that penetrates the gasket and engages with a hole in the reinforcing member. 1. An oil pan mounting structure for an engine, characterized in that the protrusion has a tapered shape, and the base thereof is larger than the size of the hole in the reinforcing member.