JPH05164190A - Balancer device of engine - Google Patents

Abstract

PURPOSE:To prevent inclination at the bearing site of a balance shaft each of which is supported at two places. CONSTITUTION:This is an engine balance device in which a balance shaft 10 is supported by means by two bearings 15, 16, and balance masses 13, 14 are arranged on both sides of one bearing 16. And balance shaft inclination at a bearing 16 place between two balance masses 13, 14 is made approximately zero by making unbalanced element of the balance mass 13 positioned between the two bearings larger than the unbalanced element of the other balance mass 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine balancer device.

[0002]

2. Description of the Related Art Conventionally, in a reciprocating type (reciprocating) engine, balance shafts are provided on both sides of the crankshaft in parallel with the crankshaft, and are rotated in synchronism with the crankshaft. A balancer device for an engine that suppresses the above is known.

The balance shaft is normally supported at three points, but Japanese Patent Publication No. 57-44863 discloses a balance shaft as shown in FIGS. 3 and 4 for the purpose of reducing drive loss and weight of the balance shaft. The shaft is provided with two journal parts 1 and 2 for each bearing,
Disclosed is a balancer device in which the balance mass is supported by 6 and the balance mass is divided in the axial direction of the balance shaft so that the balance masses 3 and 4 are arranged on both sides of one journal portion 2.

[0004]

However, in the conventional balancer device, the unbalanced components of the balance masses 3 and 4 are
Both sides of the bearing 6 are the same, that is, only the mass balance between the balance masses 3 and 4 on both sides of the bearing 6 is considered. However, in reality, another bearing 5 is necessary to support the entire balance shaft, and the presence of this bearing 5 causes the bearing 6 that supports the balance masses 3 and 4 to be supported.
The deformation modes of the balance shaft on both sides of the bearing 6 are different from each other, and there is a problem in that the bearing 6 is subjected to one-sided contact, which causes uneven wear and seizure at the bearing portion.

This will be described in the deformation mode of the balance shaft as shown in FIG. The mass 3 between the two bearings 5 and 6 is supported at both ends, but the other mass 4 is cantilevered. In this case, uneven wear occurs. Therefore, the bearing load on the bearing 6 is locally increased, which causes seizure of the bearing and peeling of the bearing metal, which is a problem in terms of reliability.

According to the present invention, in a balancer device for an engine in which a balance shaft is supported by two bearings, and the balance mass is divided and arranged on both sides of one bearing, when the balance shaft rotates in the bearing portion between the balance masses. It is an object of the present invention to solve the problem existing in the above-mentioned conventional device by making the inclination of the balance shaft almost zero.

[0007]

According to the present invention, the above object is achieved by the following engine balancer device. That is, the first journal portion is formed at one end of the balance shaft, and the second journal portion is formed at a portion separated from the one end to the other end side, and the balance mass is divided to form the second journal. A balancer device for an engine, in which the balance shaft is distributed to both sides in the axial direction, and the balance shaft is supported by a first bearing at the first journal portion and supported by a second bearing at the second journal portion. When the first journal is rotated, the first journal is adjusted so that the inclination of the second journal is almost zero.
The unbalanced component of the balance mass located between the second journal unit and the second journal unit is larger than the unbalanced component of the balance mass located on the opposite side of the first journal unit from the second journal unit. A balancer device for the engine.

[0008]

In the engine balancer device of the present invention, the first,
Since the unbalanced component of the balance mass between the second journal portions is set to be larger than the unbalanced component of the other balance mass, when the balance shaft rotates, the portion between the first and second bearings of the balance shaft is larger than in the conventional case. It is greatly deformed, and by this deformation, the inclination of the second journal portion can be made almost zero. Although the inclination of the first journal portion is larger than that of the conventional one, the load applied to the first bearing portion from the balance mass is much smaller than the load on the second bearing portion, and therefore the first bearing portion is worn away. The above problem does not occur.

[0009]

1 and 2 show a preferred embodiment of the present invention. 1-2, the balance shaft 10
Is supported at two points per one, and is supported by the first bearing 15 and the second bearing 16. Balance shaft 1
0 is arranged in parallel with the crankshaft of a reciprocating engine (not shown) and has a structure that rotates in synchronization with the crankshaft. The first and second bearings 15 and 16 are fixed to a partition wall of the engine cylinder block that extends in a direction orthogonal to the crankshaft, and the balance shaft 10 extends from the cylinder block via the first and second bearings 15 and 16. Supported.

The balance shaft 10 has two journal parts, namely a first journal part 11 and a second journal part 12, which are supported by a first bearing 15 on the first journal part 11 and a second journal part. It is supported at the part 12 by a second bearing 16. The first journal portion 11 is formed at one end portion of the balance shaft 10, and the second journal portion 12 is formed at a portion separated from the one end portion of the balance shaft to the other end portion side.

The balance mass of the balance shaft 10 is
The balance mass 13 is divided into two, and one balance mass 13 is formed between the two journal portions 11 and 12 of the balance shaft 10.
The other balance mass 14 is formed on the opposite side of the first journal portion 11 from the second journal portion 12. Therefore, the second bearing 16 has two balance masses 1
It is located between 3 and 14 and supports most of the load applied from the balance masses 13 and 14.

Of the balance masses 13 and 14, the unbalanced component of the first balance mass 13 between the first and second journal portions 11 and 12 is the balance mass 1 of the other balance mass 1.
It is larger than the unbalanced component of 4. The ratio of the unbalanced components of the balance masses 13 and 14 to the magnitude of the unbalanced component is such that when the balance shaft 10 rotates,
Is set to be substantially 0 (including 0).

Next, the operation will be described. When the crankshaft rotates during engine operation, the balance shafts 10 arranged on both sides of the crankshaft also rotate and balance the unbalanced mass of the reciprocating engine mass to suppress vibration.

Since the balance shaft 10 has the balance masses 13 and 14 having an unbalanced component, a centrifugal force component acts in the direction orthogonal to the axis when the balance shaft 10 rotates, and bending deformation occurs as shown in FIG. The unbalanced component of the first balance mass 13 is the second balance mass 1
Since it is larger than the unbalance component of 4, the portion of the first balance mass 13 is deformed more than before, and the inclination of the second journal portion 12 becomes almost zero.

The difference becomes even clearer when compared with the conventional modification of FIG. Conventionally, two balance masses 3,
Since the unbalance components of No. 4 are the same, the deformation of the balance mass 3 at both ends is small, and the second journal portion 2 is deformed to be inclined toward the other balance mass 4 side.

However, in the present invention, as shown in FIG.
Since the unbalance component of the first balance mass 13 is large, the load applied to the first balance mass 13 is large, and the second balance mass 14 of the second journal portion 12 is large.
The first balance mass 13 can generate an inclination enough to cancel the inclination of the second journal portion 12, and as a result, the inclination of the second journal portion 12 becomes substantially zero.

Since the inclination of the second journal portion 12 from the axis of the balance shaft is substantially zero, uneven contact of the second bearing 16 and uneven wear of the bearing and journal portion due to uneven contact are suppressed.

As can be seen from the comparison between FIG. 2 and FIG. 4, in the present invention, the inclination of the first journal portion 11 is larger than that of the conventional one, but it is orthogonal to the axial center due to the unbalanced components of the balance masses 13 and 14. Since the directional force component is mainly received by the second bearing 16 and a large load is not applied to the first bearing 15, a problem in wear does not occur or is unlikely to occur.

[0019]

According to the present invention, the unbalance component of the first balance mass is made larger than that of the second balance mass, so that the inclination of the balance shaft in the second journal portion becomes substantially zero. It is possible to prevent the occurrence of defects such as uneven contact, uneven wear, and seizure in the second bearing.

[Brief description of drawings]

FIG. 1 is a side view of a balance shaft used in a balancer device for an engine according to an embodiment of the present invention.

FIG. 2 is a deformation mode diagram of the balancer device in which the balance shaft of FIG. 1 is mounted on a bearing.

FIG. 3 is a side view of a conventional two-position supporting balance shaft.

4 is a deformation mode diagram of a balancer device in which the balance shaft of FIG. 3 is mounted on a bearing.

[Explanation of symbols]

 10 balance shaft 11 1st journal part 12 2nd journal part 13 1st balance mass 14 2nd balance mass 15 1st bearing 16 2nd bearing

Claims (1)

[Claims] 1. A first journal portion is formed at one end portion of a balance shaft, and a second journal portion is formed at a portion separated from the one end portion to the other end portion side to divide a balance mass into the first journal portion. A balancer device for an engine, wherein the balance shaft is distributed to both sides in the axial direction of two journal parts, and the balance shaft is supported by a first bearing at the first journal part and supported by a second bearing at the second journal part. , So that the tilt generated in the second journal portion when the balance shaft rotates becomes almost zero.
The unbalanced component of the balance mass located between the second journal unit and the second journal unit is larger than the unbalanced component of the balance mass located on the opposite side of the first journal unit from the second journal unit. A balancer device for the engine.