JPH0730690B2 - Bearing device for multi-cylinder engine - Google Patents

Abstract

PURPOSE:To prevent the generation of hammering noises, by constituting a crankshaft-1st end bearing interlocked with an auxiliary machine on a combustion chamber side by means of a semi-split sliding bearing provided with no oil groove and placed on the combustion engine side, and of the other semi-split sliding bearing provided with an oil groove and placed on the opposite side. CONSTITUTION:An auxiliary machine 8 placed on the side of a combustion chamber 9 via a pulley 6 and a belt 7 is interlocked with the 1st end 1a on one side of a crankshaft 1. Each of sliding bearing 21-25 is composed of a semi-split sliding bearing 2a provided with an oil groove and a semi-split sliding bearing 2b provided with no oil groove, with the 1st sliding bearing 21 adjacent to the 1st end 1a being such that the semi-split bearing 2b provided with no oil groove is placed on the side of the combustion chamber 9 from the crankshaft 1 and the semi-split bearing 2a provided with the oil groove on the opposite side thereto.

Description

TECHNICAL FIELD The present invention relates to a bearing device for a multi-cylinder engine, and more particularly to a bearing device for a multi-cylinder engine in which a crankshaft is axially supported through at least three slide bearings. It is about.

"Prior Art" Conventionally, in-series or V-type multi-cylinder engines generally include a crankshaft that is rotatably supported by at least three or more slide bearings in its crankcase, and a plurality of crank portions formed on the crankshaft. It has a connecting rod connected to each and a piston connected to each connecting rod.

Further, each of the slide bearings is composed of a half slide bearing having an oil groove and a half slide bearing having no oil groove, and the half slide bearing having the oil groove is located closer to the combustion chamber than the crankshaft. It is known that a half plain bearing having no oil groove is arranged on the opposite side.

By arranging a half-sliding bearing without an oil groove on the side opposite to the combustion chamber side, the explosion pressure applied to the crankshaft via the piston and connecting rod can be obtained with a half-sliding bearing without an oil groove. I can receive it,
The bearing capacity can be improved as compared with the case of using a half slide bearing having an oil groove.

Lubricating oil for each crank portion is formed in the lubricating oil passage formed in the crankcase that communicates with the oil groove of each slide bearing and in the crankshaft that communicates the oil groove of each slide bearing with each crank portion. It can be smoothly and sufficiently supplied through the above-mentioned lubricating oil passage.

By the way, in recent years, not only fans and dynamos but also many auxiliary machines such as compressors for air conditioners, pumps for power steering, or air compressors for superchargers have come to be attached to engines, and these are generally installed. It is arranged closer to the combustion chamber than the crankshaft and is linked to one first end of the crankshaft via a pulley and a belt.

As a result, for the first slide bearing adjacent to the first end of the crankshaft, a relatively large load is applied to the half slide bearing on the combustion chamber side via the belt and the pulley, and the combustion chamber If there is an oil groove in the half slide bearing on the side, the pressure receiving area will decrease accordingly and the surface pressure will increase to reduce the oil film thickness.Therefore, contact between the crankshaft and the half slide bearing will occur. It becomes easy and causes a tapping sound.

For this reason, conventionally, in consideration of the hammering sound and the load due to the explosion pressure, both the half slide bearings are composed of half slide bearings having no oil groove for the first slide bearing only. A bearing device has been proposed (JP-A-58).
-24613 publication).

[Problems to be Solved by the Invention] According to such a bearing device, the hammering noise is reduced as compared with a bearing device in which the first sliding bearing uses a half sliding bearing on the combustion chamber side having an oil groove. Can be achieved,
On the other hand, since the first slide bearing does not have an oil groove, lubricating oil is supplied to the first crank portion adjacent thereto by using the oil groove of the second slide bearing adjacent to the first slide bearing. Will be supplied.

It has been found that such a supply of lubricating oil has no problem with respect to the supply of lubricating oil itself, but has a problem in terms of compatibility of crankshafts. That is, in many conventional crankshafts, at least the lubricating oil for the first crank portion is the first
When the lubricating oil for the first crank portion is supplied from the oil groove of the second sliding bearing as described above, the oil is supplied from the oil groove of the sliding bearing. The result was that it was not applicable.

[Means for Solving the Problems] In view of such circumstances, the present invention relates to the above-mentioned bearing device, that is, each of the above-mentioned slide bearings, to a half slide bearing having an oil groove and a half slide bearing having no oil groove. And a half-sliding bearing having the oil groove is arranged closer to the combustion chamber than the crankshaft, and a half-sliding bearing having no oil groove is arranged on the opposite side of the crankshaft. In the bearing device, the formed lubricating oil passage is communicated with the oil groove of each slide bearing, and the oil groove of the slide bearing and each crank portion are communicated with each other through the lubricating oil passage formed on the crankshaft. An auxiliary machine interlocked with one first end of the shaft is arranged on the combustion chamber side of the crankshaft, and only the first slide bearing adjacent to the first end of the crankshaft has no oil groove. Divide in half The slide bearing is arranged on the combustion chamber side with respect to the crankshaft, and the half slide bearing having an oil groove is arranged on the opposite side of the crankshaft. Further, the oil groove of the first slide bearing and the first crank portion adjacent to the oil groove are formed. A lubricating oil passage formed on the crankshaft is used for communication.

[Operation] According to such a configuration, the half sliding bearing having no oil groove of the first sliding bearing can effectively suppress the hammering sound generated by the load from the auxiliary machine, and further, the first crank portion. Since lubricating oil can be supplied from the oil groove of the first slide bearing, many existing crankshafts can be applied.

Then, in the first slide bearing having the above structure, the load due to the explosion pressure is received by the half slide bearing having the oil groove. With such a configuration, compared with the conventional device in which the half slide bearing of the first slide bearing is a half slide bearing that does not have an oil groove, theoretically, the bearing capacity is lowered. However, in a multi-cylinder engine, the load conditions for the slide bearings located at both ends of the crankshaft are not as severe as the load conditions for the slide bearings located in the middle thereof, and both the device of the present invention and the first slide bearing are oil-loaded. It was confirmed that no substantial difference in bearing capacity was observed when compared with the conventional device composed of a half plain bearing having no groove.

Therefore, according to the present invention, it is possible to suppress the generation of hammering noise while maintaining the compatibility with many crankshafts without lowering the bearing capacity as compared with the conventional device.

[Embodiment] The present invention will be described below with reference to the illustrated embodiment. FIG. 1 shows an embodiment in which the present invention is applied to an in-line four-cylinder engine. A crankshaft 1 having four crank portions 11 to 14 is shown.
Are pivotally supported on the crankcase 3 by five slide bearings 21 to 25 arranged on both sides of each crank portion. One end of the connecting rod 4 is connected to each of the crank portions 11 to 14, and each connecting rod 4 is connected.
The pistons 5 are connected to the other ends of the respective.

An auxiliary machine 8 is linked to one of the first ends 1a of the crankshaft 1 via a pulley 6 and a belt 7, and the auxiliary machine 8 is arranged closer to the combustion chamber 9 than the crankshaft 1 is. There is.

Each of the slide bearings 21 to 25 includes a half slide bearing 2a having an oil groove and a half slide bearing 2b having no oil groove, and is adjacent to the first end 1a of the crankshaft 1. In the first slide bearing 21, the half slide bearing 2b having no oil groove is arranged on the combustion chamber 9 side of the crankshaft 1, and the half slide bearing 2a having an oil groove is arranged on the opposite side. On the other hand, in the other slide bearings 22 to 25, the half slide bearing 2a having the oil groove is arranged closer to the combustion chamber 9 than the crankshaft 1, and the half slide bearing 2b having no oil groove is provided. It is located on the opposite side.

In addition, the half slide bearings 2a, 2b of the above slide bearings 21-25 are also used.
Is supported by the crankcase 3 on the half slide bearing arranged on the combustion chamber 9 side, and the half slide bearing on the opposite side is supported by the cap 10 (see FIG. 2) bolted to the crankcase 3. There is.

Further, the same number of lubricating oil passages 15 as the slide bearings are branched and formed in the crankcase 3, and as shown in FIG. 2, the lubricating oil passages are provided to the oil groove 16 of the first slide bearing 21.
Lubricating oil can be supplied from 15 through an arcuate groove 17 formed on the back surface of each half slide bearing 2a, 2b and an oil hole 18 formed in the half slide bearing 2a. On the other hand, to the oil grooves of the other slide bearings 22 to 25, the lubricating oil passages 15
The lubricating oil can be directly supplied through the oil hole 18 formed in the half plain bearing 2a.

As shown in FIG. 1, the oil groove 16 of the first slide bearing 21 and the first crank portion 11 adjacent to the oil groove 16 are formed by a lubricating oil passage 19 (see FIG. 2) formed in the crankshaft 1. While communicating, the oil grooves and crank parts of the other slide bearings are cranked from the oil grooves of the slide bearings 22 to 24 on the first end 1a side to the crank parts 12 to 14 on the opposite side. A lubricating oil passage 19 formed in the shaft 1 communicates with each other.

According to the above configuration, except for the first slide bearing 21, for the other slide bearings 22 to 25, the half slide bearing 2b having no oil groove 16 is arranged on the opposite side of the crankshaft 1 to the combustion chamber 9. Therefore, the explosion pressure applied to the crankshaft 1 via the piston 5 and the connecting rod 4 can be received by the half slide bearing 2b having no oil groove 16 therein,
Therefore, the bearing capacity can be enhanced as compared with the case of using the half slide bearing 2a having the oil groove 16.

Further, regarding the first slide bearing 21, the auxiliary machine 8 is
Is applied to the combustion chamber 9 via the belt 7 and the pulley 6.
It is added to the half slide bearing 2b on the side, but this half slide bearing is
Since 2b does not have the oil groove 16, it is possible to secure a thicker oil film thickness than in the case of using the half slide bearing 2a having the oil groove 16 and suppress the generation of hammering noise.

In addition, the lubricating oil to each crank portion 11 to 14 can be smoothly and sufficiently supplied from the oil groove 16 of each slide bearing 21 to 24 through the lubricating oil passage 19 formed in the crankshaft 1. At that time, since the lubricating oil to the first crank portion 11 is supplied from the oil groove 16 of the first sliding bearing 21, it is possible to apply many existing crankshafts as they are.

FIG. 3 shows an embodiment in which the present invention is applied to a V-type 6-cylinder engine. In this embodiment, two crank parts are used.
11a, 11b, 12a, 12b, 13a, 13b are formed adjacent to each other as a pair, and sliding bearings 21 to 24 are arranged on both sides of the crank portion of the pair, and the lubricating oil formed on the crankshaft 1 is formed. The passages 19 respectively communicate between the crank portions and the oil grooves of the slide bearings adjacent to the crank portions.

Also in this embodiment, each of the slide bearings 21 to 24 is composed of a half slide bearing 2a having an oil groove and a half slide bearing 2b having no oil groove.
In the first slide bearing 21 adjacent to the first end 1a of the above, a half slide bearing 2b having no oil groove is provided on the combustion chamber 9 side of the crankshaft 1 with a half slide bearing 2b having an oil groove. The other slide bearings 22 to 24 are arranged on the opposite side, and the half slide bearing 2a having the oil groove is arranged closer to the combustion chamber 9 side than the crankshaft 1, and the half slide bearing does not have the oil groove. bearing
2b is placed on the opposite side.

The other structure is the same as that of the above-described embodiment, and the same or corresponding parts are designated by the same reference numerals.

Next, Fig. 4 shows the result of an experiment measuring the loudness of the hammering sound. This experiment shows that the in-line four-cylinder 1600cc engine is operated at 2000 rpm for one cycle, that is, the crankshaft rotates two times. The vibration acceleration of the engine block during measurement is measured, and the maximum vibration acceleration is plotted. In the figure, the solid line indicates the engine
The dotted line shows the result when a torque of 4 kg-m was applied and a torque of 8 kg-m was added.

Further, as a comparative device to the device of the present invention, a half slide bearing having an oil groove for all of the slide bearings is arranged on the combustion chamber side of the crankshaft, and a half slide bearing having no oil groove is arranged on the opposite side. The device X and the conventional device B in which only the first slide bearings were composed of the half slide bearings each having a half slide bearing having no oil groove were used.

As can be understood from the above experimental results, the device of the present invention can clearly reduce the tapping sound as compared with the conventional device X, and the substantially same effect as that of the conventional device B can be obtained. That is, from the experimental results of the device of the present invention and the conventional device B,
Regarding the first slide bearing, even if an oil groove is formed in the half slide bearing on the side opposite to the combustion chamber side, it means that the hammering sound does not increase, and as can be inferred from this, the present invention It has been confirmed that there is no substantial difference in other bearing capabilities between the device and the conventional device B.

[Advantages of the Invention] As described above, according to the present invention, it is possible to suppress the generation of hammering noise while maintaining compatibility with many crankshafts as compared with the conventional device, and at least with the conventional device. The effect that the same bearing capacity can be maintained is obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a multi-cylinder engine showing an embodiment of the present invention, FIG. 2 is a sectional view of a first slide bearing 21 shown in FIG. 1, and FIG. 3 is another embodiment of the present invention. FIG. 4 is a schematic configuration diagram shown in FIG. 1 ... Crank shaft, 3 ... Crank case 2a ... Half-slide bearing with oil groove 2b ... Half-slip bearing without oil groove 4 ... Connecting rod, 5 ... Piston 9 ... Combustion chamber, 15, 19 …… Lubricating oil passages 11 to 14, 11a, 11b, 12a, 12b, 13a, 13b …… Crank part 16 …… Oil groove, 21 …… 1st sliding bearing 22 to 25 …… Sliding bearing

Claims (3)

[Claims] 1. A crankshaft of a series-type or V-type multi-cylinder engine, which is axially supported by at least three or more slide bearings, and a plurality of crank portions formed on the crankshaft. A connecting rod and a piston connected to each connecting rod are provided, and each of the slide bearings is composed of a half slide bearing having an oil groove and a half slide bearing having no oil groove, and having the oil groove. The half slide bearing is located closer to the combustion chamber than the crankshaft, the half slide bearing without an oil groove is located on the opposite side, and the lubricating oil passage formed in the crankcase is used for the oil of each slide bearing. Of a multi-cylinder engine in which the oil groove of the slide bearing and each crank portion are communicated with each other through a lubricating oil passage formed on the crankshaft In the receiving device, an auxiliary machine that is interlocked with one of the first ends of the crankshaft is arranged closer to the combustion chamber than the crankshaft, and only the first slide bearing adjacent to the first end of the crankshaft is provided. A half slide bearing having no oil groove is arranged on the combustion chamber side with respect to the crankshaft, a half slide bearing having an oil groove is arranged on the opposite side thereof, and the oil groove of the first slide bearing is adjacent to the oil groove. A bearing device for a multi-cylinder engine, wherein the first crank portion is communicated with a lubricating oil passage formed on the crank shaft. 2. Two crank parts are formed adjacent to each other as a pair, and plain bearings are arranged on both sides of the crank parts of the pair, and a lubricating oil passage formed in the crankshaft is provided in each crank part. The bearing device for a multi-cylinder engine according to claim 1, wherein the bearing and the oil groove of the slide bearing adjacent to the bearing are communicated with each other. 3. Sliding bearings are respectively arranged on both sides of the crank portion of the crankshaft, and a lubricating oil passage formed in the crankshaft is provided on each crank portion and on each slide adjacent to the crank end on the first end side. The bearing device for a multi-cylinder engine according to claim 1, wherein the bearing device communicates with an oil groove of the bearing.