JPS5943485Y2 - Engine body of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a structure of an engine body that prevents vibrations of the crankcase and oil pan in an internal combustion engine in which the oil pan is attached to the lower surface of the crankcase.

In recent years, there has been an increasing demand for noise prevention measures for vehicles, and among these, the vibration of the engine crankcase not only causes vibration noise at the bottom of the crankcase, but also noise from the oil pan attached to the bottom of the crankcase. Therefore, there is an urgent need to take measures to prevent vibrations.

Crankcase vibration is especially caused by the lower part of the crankcase,
The main reason for this is that the lower part vibrates in and out of the case because the rigidity of the connection part with the oil pan is low.

For this reason, attempts have been made in the past to suppress crankcase vibration by interposing a reinforcing frame between the crankcase and the oil pan to increase the rigidity of the lower part of the crankcase.

However, in such a reinforced frame, there is a gap between the through bolt that fastens the oil pan and the crankcase and the bolt insertion hole formed in the frame, so relative movement occurs between the frame and the crankcase, causing the frame to move. The rigidity was not fully utilized, and the effect of preventing vibration of the crankcase could not be fully achieved.

Although it is possible to weld the reinforcing frame to the crankcase in advance to seal off the relative movement, in this case the frame cannot be removed and inspection of the engine,
This will impede repairs.

Therefore, this invention eliminates relative movement with the crankcase,
Furthermore, by attaching a removable reinforcing frame, the rigidity of the crankcase can be more completely strengthened, thereby providing an engine body that thoroughly prevents noise caused by vibrations of the crankcase and oil pan.

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

FIG. 1 shows the structure of the reinforcing frame used in this embodiment.

That is, the holes 11 to 14 are formed in a plate material having sufficient rigidity by pressing or the like, leaving the horizontal frames 15 to 11.

The holes 11 to 14 do not interfere with the movement of the moving parts of the engine or the operation of the oil scooping member, and they also allow oil to be scooped up from the oil pan to the crankcase side and from the crankcase side to the oil pan. The area should be large enough to guarantee against falling.

Furthermore, a plurality of insertion holes 18 for fastening bolts between the crank case and the oil pan are formed in the peripheral portion of the frame 1.

A plurality of knock pins 19, which are fitting protrusions according to the present invention, are implanted into the reinforcing frame 1 having such a structure.

On the other hand, on the oil pan connection flange of the crankcase,
A plurality of fitting holes are formed at positions corresponding to the knock pins 19.

FIG. 2 shows the structure of an engine body in which such a reinforcing frame 1 is interposed.

Specifically, an oil seal gasket 4 is interposed between the lower surface of the crankcase 2 and the reinforcing frame 1, and the reinforcing frame 1 is attached to the lower surface of the crankcase 2 by fitting the knock pin 19 into the fitting hole 21.

Further, a gasket 5 is interposed between the reinforcing frame 1 and the upper surface of the oil pan 3, and the crankcase 2 and the oil pan 3 are screwed together using bolts 6 and nuts 7.

The gasket may be a liquid gasket other than a plate-shaped gasket.

According to this configuration, the knock pin 19 and the fitting hole 21 are tightly fitted, so even if there is a gap between the bolt 6 and the insertion hole for the bolt 6 formed in the flange portion of the crankcase 2, the crankcase 2 and the reinforcing frame 1 are securely fixed without relative movement, so the rigidity of the reinforcing frame 1 is fully utilized.

Therefore, the vibration of the crankcase 2 is further reduced, and the vibration of the oil pan 3 accompanying the crankcase 2 is also reduced, so that the noise radiated from the crankcase and the oil pan is significantly reduced compared to the conventional case.

In the above embodiment, the reinforcing frame 1 is shown in which the dowel pins 19 are implanted only on the crankcase 2 side, but as shown in FIG. The reinforcing frame 1 may be provided with knock pins 19 and may also be fitted with the oil pan 3.

In this way, the state of connection with the oil pan 3 is also strengthened, and the noise reduction effect can be further enhanced.

Alternatively, a reamer bolt may be used instead of a knock pin as the fitting protrusion, and a corresponding fitting hole may be provided on the crankcase side.

Incidentally, a fitting protrusion may also be provided on the oil pan side of the reinforcing frame so as to fit with the oil pan.

In this case, the state of connection with the oil pan is also good, and the noise reduction effect can be further enhanced.

As described above, the present invention greatly contributes to the prevention of vibration and noise of the engine body, since the rigid reinforcing frame, which is easily removable and has a simple structure, is interposed in the crankcase without causing any relative movement. It is.

Further, the reinforcing frame can be easily assembled and the number of bolts for connecting the oil pan can be reduced, so the assembly workability is much better than that of a conventional structure using a reinforcing frame.

[Brief explanation of the drawing]

Fig. 1 shows a plan view and a front view of a reinforcing frame used in one embodiment of the present invention, Fig. 2 shows a configuration diagram of the engine body to which the frame is attached, and Fig. 3 shows another embodiment of the invention. FIG. 1... Reinforcement frame, 2... Crank case, 3.
...Oil pan, 4,5...Gasket, 6...Bolt, γ...Nut, 19...Rack pin, 21...
Fitting hole.

Claims (2)

[Scope of utility model registration request] (1) In an internal combustion engine in which an oil pan is attached by interposing a reinforcing frame on the lower surface of the crankcase, a fitting protrusion is provided at least on the crankcase side of the reinforcing frame,
An engine body for an internal combustion engine, characterized in that a crankcase is provided with a fitting hole that fits into the fitting protrusion. (2) The engine body of an internal combustion engine according to claim 1, wherein the fitting protrusion is a knock pin or a reamer bolt.