JPS632586Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a crankcase sound insulation device for alleviating noise generated by an engine.

FIG. 1 is a side view of the engine, where 1 is a crankcase, 2 is a side wall, 3 is an oil pan, and A is a mounting flange for the oil pan. The conventional crankcase sound insulation device 3 has a sound absorbing material 4 covered with a cover 5 as shown in FIG.
The side cover 6 that has been covered and molded is attached to the oil pan 2.
The sound absorbing material 4 was attached to the crankcase side wall 2 with an adhesive directly above the mounting flange A, but this method increases the spring constant of the sound absorbing material 4 and reduces the vibration of the sound insulation device. The drawback was that the insulation effect was insufficient.

SUMMARY OF THE INVENTION An object of the present invention is to provide a crankcase sound insulation device that can reduce noise generated from an engine.

The crankcase sound insulation device of the present invention has substantially parallel ribs protruding from the oil pan mounting flange of the crankcase, and the peripheral edges of a plate-shaped sound absorbing material are joined between the two side walls to seal the sound absorbing material. The above object is achieved by providing a gap between the member and the side wall of the crankcase.

An embodiment of a crankcase sound insulation device according to the present invention will be described below with reference to FIGS. 3 to 7. Here, the same or equivalent components as those of the conventional device will be described using the same reference numerals.

FIG. 3 shows a first embodiment of the present invention, showing a crankcase side wall 12 having an oil pan mounting flange A.
protrudingly provided with a rib B substantially parallel to the flange A;
Furthermore, in order to block and absorb sound radiated from the crankcase side wall 12 and to improve the vibration insulation effect, a side cover 16a with a sound absorbing material 14 covered with a cover plate 15a is installed on both sides of the ribs A and B. The peripheral portion 19 is in contact with the crank case side wall 12 for sealing, and is mounted with a gap left between the crank case side wall 12 and the crank case side wall 12. Therefore, the newly installed rib B on the crankcase improves the rigidity of the crankcase and seals out leakage noise.At the same time, it is installed with a gap between the ribs B and the crankcase, and comes into contact with the crankcase at the peripheral part 19 of the sound absorbing material. Therefore, the vibration component in the direction perpendicular to the surface of the crankcase body can be blocked in the shear direction, thereby lowering the spring constant of the soundproofing material 14 and improving the vibration insulation effect.

Also, the stay 18 welded to the cover plate 15a
A is a member required when attaching the sound absorbing material 14 to the cover plate 15a, and after the sound absorbing material 14 is brought into close contact with the cover plate 15a, the stay 18a is bent to form a clip.

Figures 4 and 5 show the sound absorbing material 1 in the second and third embodiments.
4 are respectively attached to the covers 15b and 15c with an adhesive or a pin 18c, but the operation and effect thereof are exactly the same as in the first embodiment. FIG. 6 shows a fourth embodiment in which the sound absorbing material 14 is sandwiched between the rib C of the case side wall and the side cover 15d, and FIG.
In the embodiment, the sound absorbing material 14 is inserted between the case side wall rib C and the beat portion D of the side cover 15e, but the operation and effect are almost the same as in the first embodiment.

In the first to fifth embodiments, the protective side covers 16a, 16b, 16c, 16d, and 16e are
Each of them is screwed onto the crankcase side wall 12 via an elastic member such as a rubber washer (not shown) with a screw that is prevented from rotating.

According to the present invention, a substantially parallel rib is protruded from the oil pan mounting flange of the crankcase, and the peripheral edge of the plate-shaped sound absorbing material is joined between the two side walls, and the sound absorbing member and the side wall of the crank case are connected to each other. Since there is a gap between them, the rigidity of the crankcase is improved, which helps seal out leakage noise, blocks vibration components in the direction perpendicular to the surface of the crankcase body in the shear direction, and lowers the spring constant of the sound-absorbing material. However, the vibration insulation effect can be improved.

[Brief explanation of the drawing]

Figure 1 is a front view of the engine showing how the side cover, which is a sound insulation device, is installed. Figure 2 is a sectional view of a conventional crankcase sound insulation device. Figures 3 to 7 are cross sections of a sound insulation device according to the present invention. In the figure, Figure 3 is the first
Examples FIG. 4 shows a second embodiment, FIG. 5 shows a third embodiment, FIG. 6 shows a fourth embodiment, and FIG. 7 shows a fifth embodiment. 12...Crankcase side wall, 14...Sound absorbing member, 19...Sound absorbing material peripheral surface, A...Crankcase oil pan mounting flange, B...Rib substantially parallel to flange A.

Claims (1)

[Scope of utility model registration request] A rib substantially parallel to the flange is provided on the side wall of the crankcase having the oil pan mounting flange, and a peripheral end surface of the plate-shaped sound absorbing material is connected between the side surface of the rib and the side surface of the flange. A sound insulation device for a crankcase, characterized in that a gap exists between the member and the crankcase.