JPH06264974A - Crankshaft of in-line five-cylinder engine - Google Patents

Abstract

PURPOSE:To provide a crankshaft capable of effectively reducing oscillation of a an in-line a five-cylinder engine of equal interval ignition connected to a transmission and others and forming a power plant. CONSTITUTION:By setting a couple balance rate of a balance weight 2 of a crankshaft 1 of an in-line five-cylinder engine of equal interval ignition connected to a transmission and others and forming a power plant as 100% of a rotational part mass + 10-30% of a reciprocating part mass, oscillation of an engine in the state of constituting the power plant by way of connecting it with the transmission and others is reduced, and it is possible to lighten the engine and to improve the fuel consumption.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crankshaft of an in-line 5-cylinder engine, and more particularly, to further reduce the vibration of an equally-spaced ignition in-line 5-cylinder engine which is combined with a transmission and constitutes a power plant. It is related to the crankshaft.

[0002]

2. Description of the Related Art In an in-line five-cylinder engine having an equal interval ignition, a primary couple and a secondary couple remain. this house,
The primary couple is due to the mass of the rotating part and the mass of the reciprocating part, and the mass due to the mass of the rotating part is as shown by the curve a in FIG. Further, since the mass due to the reciprocating portion is a reciprocating motion along the vertical direction in FIG. 5, the combined primary couple (couple before unbalance) becomes as shown by curves b in FIGS. 5 and 6. . However, the couple b before balancing cannot be made zero by the balance weight provided on the crankshaft.

For this reason, in the prior art, 100
% + 50% of the reciprocating portion couple. By providing a balance weight of 50% overbalance, the couple c of this balance weight and the couple b before the balancing (combined couple) (after balancing) As shown by the curve d in FIG. 6, the couple has the same minimum value in both the pitching direction and the yawing direction.

By the way, when a power plant is constructed by coupling an engine with a transmission like an automobile engine, the coupling rigidity between the engine and the transmission in the pitching direction is larger than the coupling rigidity in the yawing direction.

Therefore, when the crankshaft is provided with a balance weight in which the couple d after balancing is equalized in the pitching direction and the yawing direction as in the prior art, the engine alone can achieve the intended purpose. However, there was a problem in that the vibration of the engine when the power plant was configured could not be reduced sufficiently.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is an in-line five-cylinder engine capable of effectively reducing engine vibration in a state in which a power plant is configured by being combined with a transmission or the like. The challenge is to provide a crankshaft.

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention relates to a couple of balance weights of a balance weight of a crankshaft of an in-line 5-cylinder engine having an equal interval ignition which is combined with a transmission or the like to constitute a power plant. Rate is 100% of rotating part mass + 10-30% of reciprocating part mass
It is characterized by being set to.

[0008]

[Function] 100% of the mass of the rotating part + 10 to 3 of the mass of the reciprocating part
Since the crankshaft is provided with a balance weight set to a couple ratio of 0%, a large couple is left in the pitching direction after balancing, but the couple in the yawing direction is reduced. However, in the state where the power plant is configured by being coupled with the transmission or the like, the coupling rigidity between the engine and the transmission or the like is large in the pitching direction. Therefore, the vibration due to the couple in the pitching direction after the balance is suppressed by the coupling with the transmission.

Therefore, in the case where a power plant is configured by combining an in-line 5-cylinder engine of equal interval ignition equipped with a crankshaft having a balance weight set to the above-mentioned couple balance ratio with a transmission or the like, a pitching direction and yawing are performed. Any vibration in the direction is reduced. In addition, the weight of the balance weight can be reduced as compared with the conventional balance weight set to 50% overbalance of the mass of the reciprocating portion, so that the weight of the engine can be reduced and the fuel consumption can be improved by reducing the weight of the moving portion. .

[0010]

Embodiments of the present invention will be described in detail below with reference to the drawings. 1 is a schematic side view showing an embodiment of a crankshaft of an in-line 5-cylinder engine according to the present invention, FIG. 2 is a side view of FIG. 1, and FIG. 3 is an explanatory view of a primary couple balance state according to the embodiment. FIG. 4 is a characteristic diagram of the vibration level of the engine with respect to the couple balance ratio of the balance weight in the state where the power plant is configured.

In these figures, an in-line five-cylinder engine in which the ignition sequence is set to the first cylinder # 1, the second cylinder # 2, the fourth cylinder # 4, the fifth cylinder # 5, and the third cylinder # 3 at equal intervals. Balance weights 2 are provided at both ends of the crankshaft 1.

The balance weight 2 reduces the vibrations caused by the motions of the rotating part and the reciprocating part. In addition, the couple balance ratio of the balance weight 2 is set to 10 of the mass of the rotating portion.
0% + 10 to 30% of reciprocating mass. 3 is a bearing, 4 is a piston, and 5 is a connecting rod.

When the in-line 5-cylinder engine having the crankshaft 1 constructed as described above is operated, the primary couple before balancing accompanying the motions of the rotating part and the reciprocating part is shown by a curve A in FIG. As shown. In addition, the primary couple due to the movement of the balance weight 2 is as shown by B in FIG.
It is smaller than the primary couple due to the conventional balance weight of 50% overbalance shown by C in FIG. Therefore, the primary couple after balancing becomes large in the pitching direction as shown by the curve D, but becomes small in the yawing direction.

On the other hand, in the state where the power plant is constructed by connecting the transmission and the like to the engine,
The joint rigidity between the engine and the transmission in the pitching direction becomes larger than the joint rigidity in the yawing direction. Therefore, even if the primary couple after balancing increases in the pitching direction in the engine alone as described above, the vibration suppressing action in the pitching direction becomes large in the state in which the power plant is configured, so that The vibration level of will be reduced.

When the overbalance of the balance weight 2 is less than 10% of the mass of the reciprocating portion,
If it is set higher than%, the vibration level of the engine in the state where the power plant is configured as shown in FIG. 4 becomes high.

Further, as described above, since the couple balance ratio of the balance weight is made smaller than in the conventional case to reduce the weight of the balance weight, the weight of the engine can be reduced and the mass of the moving portion can be reduced. Therefore, fuel efficiency is also improved.

In the above embodiment, the balance weights 2 are provided only at the front and rear ends of the crankshaft 1, but the balance weights 2 may be dispersed to reduce the load deviation of the bearings 3. The balance weight 2 may be formed integrally with the crankshaft 1 or may be a split type that is attached as a separate component. Furthermore, although the present invention has been described in the embodiment as being applied to an automobile engine, the present invention is applicable to any equidistant ignition in-line 5-cylinder engine that is combined with a transmission or the like to form a power plant. You can

[0018]

As is apparent from the above description, according to the crankshaft of the present invention, it is possible to effectively reduce the vibration of the equidistant ignition in-line 5-cylinder engine which is combined with the transmission and constitutes the power plant. . Further, since the couple balance ratio of the balance weight is made smaller than the conventional one to reduce the weight, the engine is lightened and the fuel consumption is also improved.

[Brief description of drawings]

FIG. 1 is a schematic side view showing an embodiment of a crankshaft of an in-line 5-cylinder engine according to the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is an explanatory diagram of a balanced state of the primary couple according to the embodiment.

FIG. 4 is a characteristic diagram of an engine vibration level with respect to a couple balance ratio of a balance weight in a state where a power plant is configured.

FIG. 5 is an explanatory diagram of a primary couple before balancing with a balance weight.

FIG. 6 is an explanatory diagram of a primary couple after balancing with a conventional balance weight.

[Explanation of symbols]

 1 Crankshaft 2 Balance weight 3 Bearing 4 Piston 5 Connecting rod

Claims (1)

[Claims] 1. In an in-line 5-cylinder engine of equal interval ignition which is combined with a transmission or the like to constitute a power plant, the couple weight ratio of a balance weight provided on the crankshaft is 100% of the rotating part mass + the reciprocating part. A crankshaft of an in-line five-cylinder engine, characterized by having a mass of 10 to 30%.