JPH04287818A - Engine of splash lubrication type - Google Patents

Abstract

PURPOSE:To make an engine compact without extension of crank case lateral wall by eccentrically positioning the central point of rotation locus of oil dipper tip to the side opposite to one axis balancer viewed from the axial center of cylinder, and positioning the balancer in a close manner to the lateral end of the rotation locus. CONSTITUTION:An oil dipper 4 is led out from a connection rod large end part 2, and at an oil dipper tip 6 an oil dipper piece 29 bent rearwards is provided. A one axis balancer 9 is positioned in a close manner to a left lateral end part 11 of rotation locus 8 of an oil dipper piece 29, and the center 10 of the rotation locus 8 is eccentric largely to the right side viewed from a cylinder axial center 5. In comparison with the case where the center 10 is eccentric to the left side, the position of the one axis balancer 9 becomes closer to the cylinder axial center 5, and by that amount the extension of crank case lateral wall 12 facing the one axis balancer 9 becomes small accordingly. Furthermore, eccentric load due to the one axis balancer 9 becomes small by the amount corresponding to that the position of one axis balancer 9 becomes close to the cylinder axial center 5.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to splash-lubricated engines.

0002

2. Description of the Related Art As a conventional technology of a splash lubrication type engine, there is one shown in FIG. This is crankcase 10
An oil dipper 104 is led out from the connecting rod large end 102 inside the connecting rod 1 into the oil pan 103, and the cylinder axis 1
The lubricating oil 107 in the oil pan 103 is transferred to the crankcase 10 by the oil drainer tip 106 that rotates across the 05.
1, and a uniaxial balancer 109 is installed on the side of the rotation locus 108 of this oil dipper tip 106.
It is configured with the following.

[0003] According to this configuration, the interior of the crankcase 101 can be lubricated with a simple structure in which the oil dipper 104 is provided on the connecting rod large end 102, and compared to a pressure-feed lubrication type that requires a pressure-feed pump or the like, This has the advantage of reducing the cost of the engine. Further, since the heavy uniaxial balancer 109 is disposed at a low position of the engine, the center of gravity of the engine is lowered, which has the advantage of stabilizing the engine.

By the way, in this prior art, since the center point 110 of the rotation locus 108 of the oil dipper tip 106 is eccentric toward the uniaxial balancer 109 side when viewed from the cylinder axis 105, the lateral end of this rotation locus 108 111 is laterally far away from the cylinder axis 5. Therefore, the uniaxial balancer 109 disposed on the side of the lateral end 111 of the rotation locus 108 to avoid interference with the lateral end 111 also has the cylinder axis 105.
It will move far away from the side.

[0005]

[Problems to be Solved by the Invention] The above-mentioned prior art has the following problems.

■Rotation locus 1 of the oil drainper tip 106
Since the center point 110 of 08 is eccentric toward the uniaxial balancer 109 when viewed from the cylinder axis 105, the uniaxial balancer 1
09 becomes laterally far away from the cylinder axis 105. Therefore, the crankcase side wall 112 facing the uniaxial balancer 109 protrudes laterally, resulting in an enlarged engine.

■The uniaxial balancer 109 is located at the cylinder axis 10.
5, the unbalanced load caused by the uniaxial balancer 109 worsens the left-right balance of the engine.

An object of the present invention is to enable a uniaxial balancer to be brought close to the cylinder axis.

[0009]

[Means for Solving the Problems] The present invention, as illustrated in FIG. Oil drainper tip 6 that rotates across
In a splash lubrication type engine, the lubricating oil 7 in the oil pan 3 is splashed up into the crankcase 1, and a uniaxial balancer 9 is provided on the side of the rotation locus 8 of the oil dipper tip 6. , is characterized by the following configuration.

That is, the center point 10 of the rotation locus 8 of the oil dipper tip 6 is eccentrically positioned on the side opposite to the uniaxial balancer 9 when viewed from the cylinder axis 5, and the lateral end 11 of the rotation locus 8 is It is characterized in that the uniaxial balancer 9 is arranged close to the uniaxial balancer 9.

[0011]

[Function] ■ The center point 10 of the rotation locus 8 of the oil dipper tip 6 is eccentrically placed on the side opposite to the uniaxial balancer 9 side when viewed from the cylinder axis 5, and the uniaxial balancer 9 is placed at the lateral end 11 of the rotation locus 8. Since they are arranged close to each other, the uniaxial balancer 9 is placed closer to the cylinder axis 5 compared to the case where the center point 10 of the rotation locus 8 is eccentric toward the uniaxial balancer 9 when viewed from the cylinder axis 5. . For this reason, the uniaxial balancer 9
The uniaxial balancer 9 is positioned closer to the cylinder axis 5.
There is no longer a need for the crankcase side wall 12 facing the engine to extend laterally, and the engine can be made smaller.

■The arrangement of the uniaxial balancer 9 is aligned with the cylinder axis 5.
As it approaches , the unbalanced load caused by the uniaxial balancer 9 decreases, and the left-right balance of the engine improves.

[0013]

[Effects of the invention] ■The center point of the rotation locus of the tip of the oil dipper is eccentric to the side opposite to the uniaxial balancer side when viewed from the cylinder axis, and the uniaxial balancer is placed close to the lateral end of the rotation locus. Therefore, compared to the case where the center point of the rotation locus is eccentric toward the uniaxial balancer side when viewed from the cylinder axis, the arrangement of the uniaxial balancer is closer to the cylinder axis. Therefore, as the uniaxial balancer is disposed closer to the cylinder axis, there is no need to extend the side wall of the crankcase facing the uniaxial balancer to the side, and the engine can be made smaller.

■The closer the uniaxial balancer is placed to the cylinder axis, the less the unbalanced load due to the uniaxial balancer will be.
Improves left-right balance of the engine.

[0015]

[Embodiment] An embodiment of the present invention will be explained based on the drawings.

FIGS. 1 and 2 are views for explaining an engine according to an embodiment of the present invention, with FIG. 1 being a vertical cross-sectional rear view of the crankcase, and FIG. 2 being a cross-sectional plan view of the crankcase.

In FIG. 1, reference numeral 13 indicates an engine, which is constructed as follows. As shown in FIG. 1, a cylinder 14 is provided above the crankcase 1, a crankshaft 15 is housed in the crankcase 1, and the piston (not shown) in the cylinder 14 and the crankshaft 15 are connected by a connecting rod 16. ing. The lower part of the crankcase 1 is used as an oil pan 3, in which lubricating oil 7 is stored.

The crankshaft 15 has the following structure. As shown in FIG. 2, crank arms 18 are connected to the pair of front and rear crankshaft journals 17, respectively, and a crank pin 19 is interposed between the tips of both crank arms 18. A balance weight 20 is led out from the base end portions of both crank arms 18. The crankshaft 15 is installed within the crankcase 1 with the crankshaft journal 17 being supported by crankshaft bearings 21 on the front and rear walls of the crankcase 1. As shown in FIG. 1, the crankshaft 15 rotates with the axis of the crankshaft journal 17 as the rotation center 22. The rotation center 22 of the crankshaft 15 is eccentric to the left side of the cylinder axis 5.

A connecting rod big end 2 is connected to the crank pin 19 of the crankshaft 15 as follows. The connecting rod big end 2 is the rod end 23
and a connecting rod cap 24. Rod end 23
The connecting rod large end 2 and the crank pin 19 are connected by sandwiching the crank pin 19 between the connecting rod cap 24 and the connecting rod cap 24. The connecting rod cap 24 is fixed to the rod end portion 23 with a connecting rod bolt 25.

An oil dipper 4 is led out from the connecting rod big end 2 into the oil pan 3, and is structured as follows. The oil drainer 4 is L-shaped with a vertically long hanging portion 27 led out from the right end of a horizontally long base portion 26. The base portion 26 is provided with a mounting piece 28 bent toward the rear (toward the front in the drawing), and the tip of the hanging portion 27, that is, the oil drainper tip 6 is provided with an oil dipper piece 29 bent to the rear (toward the front in the drawing). It is set up. The oil dipper 4 is fixed to the connecting rod large end 2 by tightening the mounting piece 28 with a connecting rod bolt 25. Oil deppa piece 29
rotates across the cylinder axis 5 as shown by an arrow 36, causing the lubricating oil 7 in the oil pan 3 to splash up into the crankcase 1. Since the oil dipper piece 29 is arranged with a large offset to the right from the center in the left-right direction of the connecting rod large end 2, the center point 10 of its rotation locus 8 is eccentrically eccentric to the right side when viewed from the cylinder axis 5. Become.

A uniaxial balancer 9 is provided on the left side of the rotation locus 8 of the oil dipper piece 29, and is constructed as follows. As shown in FIG. 2, weights 31 are connected to a pair of front and rear balancer shaft journals 30, respectively, and both weights 31 are connected by a connecting shaft 32. crank case 1
Both balancer shaft journals 30 are supported by both balancer shaft bearings 33 on the front and rear walls, and the uniaxial balancer 9 is rotatably installed in the crankcase 1. The balancer gear 34 attached to the uniaxial balancer 9 and the crank gear 35 attached to the crankshaft 15 are meshed so that the uniaxial balancer 9 rotates in the opposite direction at the same period as the crankshaft 15, as shown in FIG. The reciprocating inertial force (outer) is offset by the rotation of the uniaxial balancer 9, and the vertical vibration of the engine is reduced. An arrow 37 indicates the rotation direction of the crankshaft 15, and an arrow 38 indicates the rotation direction of the uniaxial balancer 9.

This uniaxial balancer 9 has an oil dipper piece 2.
9 is disposed close to the left lateral end 11 of the rotation locus 8. As mentioned above, the rotation locus 8 of the oil dipper piece 29
The center point 10 is largely eccentric to the right when viewed from the cylinder axis 5. Therefore, compared to the case where the center point 10 of the rotation locus 8 is eccentric to the left side, the arrangement of the uniaxial balancer 9 is closer to the cylinder axis 5. Single axis balancer 9
The protrusion of the crankcase side wall 12 facing the uniaxial balancer 9 becomes smaller as the arrangement approaches the cylinder axis 5. Further, as the uniaxial balancer 9 is disposed closer to the cylinder axis 5, the unbalanced load due to the uniaxial balancer 9 is reduced.

Note that the reference numeral 39 in FIGS. 1 and 2 is a valve drive camshaft.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional rear view of a crankcase of an engine according to an embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of a crankcase of an engine according to an embodiment of the present invention.

FIG. 3 is a diagram corresponding to FIG. 1 of the prior art.

[Explanation of symbols]

1... Crank case, 2... Connecting rod big end, 3... Oil pan, 4... Oil dipper, 5... Cylinder axis, 6... Oil dipper tip, 7... Lubricating oil, 8... Rotation locus of 6, 9
...Single-axis balancer, center point of 10...8, lateral end of 11...8.

Claims (1)

[Claims] Claim 1: An oil dipper (4) is led out from the connecting rod large end (2) in the crankcase (1) toward the inside of the oil pan (3), and rotates across the cylinder axis (5). The lubricating oil (7) in the oil pan (3) is splashed up into the crankcase (1) by the oil dipper tip (6), and the oil dipper tip (6) is arranged to be horizontal to the rotation locus (8) of the oil dipper tip (6). In a splash lubrication type engine equipped with a uniaxial balancer (9) on the side, the tip of the oil dipper (
The center point (10) of the rotation locus (8) in 6) is eccentrically located on the side opposite to the uniaxial balancer (9) when viewed from the cylinder axis (5), and the lateral end of the rotation locus (8) is A splash lubrication type engine characterized in that the uniaxial balancer (9) is arranged close to the part (11).