JPS5922051B2 - internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an internal combustion engine in which a thrust collar is integrally formed on a crankshaft.

FIG. 1 shows the structure of a gear that drives a thrust bearing and a camshaft of a conventional marine internal combustion engine.

A thrust collar 2 is integrally connected to a crankshaft 1, and thrust force T from a propeller 3 is transferred to a base plate 5 through a thrust bearing 4.
tell to.

On the other hand, the camshaft 6 is connected to the crankshaft gear 1 and the freewheel 8. It is driven in synchronization with the crankshaft 1 via a gear 9 with a camshaft.

The disadvantage of this system is that the thrust collar 2 and the crankshaft gear T are provided separately, so the crankshaft 1 is long and the engine itself is long, which is disadvantageous when arranging the engine inside a ship.

FIG. 2 shows another example of a conventionally used thrust bearing and camshaft drive gear for a marine internal combustion engine.

Similar to the above, a thrust collar 2 is attached to the crankshaft 1.
are integrally coupled to transmit the thrust force T generated by the propeller 3 to the base plate 5 via the thrust bearing 4.

A crankshaft gear 1 that drives a camshaft 6 is fixed to the outer periphery of a thrust collar 2.

This method has the advantage that the overall length of the crankshaft and the overall length of the engine are shorter than those described above, but it has the following drawbacks.

In other words, the thrust collar 2 is deflected by δ due to the thrust force T, and the crankshaft gear T fixed to the thrust case 2 is also tilted at the same time, resulting in poor tooth contact with the protrusion 8.

Poor tooth contact can lead to serious accidents such as pitching of gears.

Another drawback is that since the crankshaft gear γ is attached to the outer periphery of the thrust collar 2, the gear I and the camshaft gear have a diameter larger than the outer diameter of the thrust collar 2, making them unnecessarily large. Becomes a gear.

An object of the present invention is to provide an engine structure that eliminates the above-mentioned drawbacks and can shorten the length of the crankshaft, and is characterized by: an internal combustion engine in which a thrust collar is integrally formed on the crankshaft; a camshaft driving gear fixed to the crankshaft in close proximity to the thrust collar;
A thrust bearing is provided outside the periphery of the gear and supported by the engine bed plate and forming half-shaped support surfaces corresponding to both end surfaces of the thrust collar.

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

FIG. 3 is a sectional view showing the structure of an engine according to an embodiment of the present invention.

In the figure, 1 is the crankshaft, 2 is the thrust collar,
It is formed integrally with the crankshaft 1.

Reference numerals 4a and 4b denote front and rear thrust bearings of the thrust collar 2, which are supported by the engine base plate 5 and form half-shaped support surfaces corresponding to the end faces of the thrust collar 2, respectively.

The thrust generated by the propeller during forward and backward movement is generated by the corresponding bearings 4a and 4.
The signal is transmitted to the engine base plate 5 via one side of b.

Crankshaft gear γ of the gear train for driving the camshaft 6
is fixed to the crankshaft in close proximity to the rear surface of the thrust collar 2.

The rear thrust bearing 4b is disposed on the outer circumferential side of the crankshaft gear γ at its outermost diameter.

The camshaft 6 is driven in synchronization with the crankshaft 1 by a gear I with a crankshaft, a gear 8 and a gear 9 with a camshaft.

That is, the above structure operates in the same manner as the conventional one.

The present invention as described above has the following effects.

(1) As shown in Fig. 3, the crankshaft gear 1 is housed in the thrust bearing part, and the rear thrust bearing 4b fits within the axial width range of the crankshaft gear γ, so the length of the crankshaft is shorter, and the overall length of the engine is shorter.

(2) Since the thrust collar 2 and the crankshaft gear γ are separated, the thrust collar 2 is generated by the thrust of the propeller.
Since the deformation of does not affect the deformation of the crankshaft gear γ,
There is no loss of tooth contact.

[Brief explanation of the drawing]

1 and 2 are sectional views showing the main parts of a conventional engine structure, respectively, and FIG. 3 is a sectional view showing the structure of an embodiment according to the present invention. 1...Crankshaft, 2...Thrust collar, 4a. 4b... Thrust bearing, 5... Engine base plate, 6... Camshaft, l... Gear with crankshaft, 8... Yugun, 9...Cam gear with bone.

Claims (1)

[Claims] 1. In an internal combustion engine in which a thrust collar is integrally formed on the crankshaft, a camshaft driving gear fixed to the crankshaft in close proximity to the thrust collar; An internal combustion engine characterized by comprising thrust bearings forming half-shaped bearing surfaces corresponding to both end faces of a thrust collar.