JPH04279709A - Fitting mechanism for lubrication oil pump - Google Patents

Abstract

PURPOSE:To reduce vibrations and noises generated from a lubrication oil pump which is fitted to the lower surface of a cylinder block within an oilpan of an engine. CONSTITUTION:A main bearing cap and a lubrication oil pump P are connected to each other by providing a center reinforcement fitting body 1 on the lower surface of a main bearing cap 17 at the center position in addition to two fitting arms 20,21 in a constitution where the lubrication oil pump P is fitted to the lower surface of a cylinder block 16 or to the lower surface of underplates 8, 7 fitted to the lower surface of the cylinder block 16.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auxiliary equipment mounting mechanism for a lubricating oil pump that is mounted on a cylinder block of an internal combustion engine.

0002

2. Description of the Related Art Conventionally, as a technique relating to an auxiliary equipment mounting mechanism for an engine, a technique such as that disclosed in Japanese Utility Model Publication No. 3-544 has been known. However, in this conventional technique and the conventional technique shown in Fig. 6, the lubricating oil pump is fixed to the engine body in a mechanism in which it is fixed to the lower surface of the cylinder block using only two mounting arms. The drive force generated between the drive gear 3 fixed to the crankshaft 12 and the pump gear 4 fixed to the lubricating oil pump shaft 5 of the lubricating oil pump P causes deformation of the mounting arm portion, and as shown in FIG. As shown in the drawing showing the problems of the prior art, the lubricating oil pump P and the pump gear 4 were bent, causing the following problems. First, the center-to-center distance between the drive gear 3 and the pump gear 4 fluctuates, and the force applied to the gear becomes irregular, reducing the durability of the gear. Second, the equivalent backlash of the gears increases, and as shown in Figure 5, which shows the state in which gear noise is generated, a situation occurs in which gear whine noise is generated at a large number of positions depending on the frequency. It was. That is, drive gear 3
This causes the gear noise between the pump gear 4 and the pump gear 4 to become louder. Furthermore, the deformation of the mounting legs deforms the cylinder block 16 and oil pan 9, resulting in an increase in radiated sound.

0003

[Problems to be Solved by the Invention] When a pair of gears are meshed and the distance between the gear axes changes, the backlash changes in magnitude, and the contact friction length and tooth surface collision noise increase. Furthermore, such deformation causes deformation of the outer circumferential surface of the drive device, which increases the vibration radiated sound, and the frequency component of the noise is such that the maximum noise level in the frequency range shown in Fig. 5 is an integer multiple of the meshing frequency of the gears. It was caused by the frequency of The present invention solves these problems.

0004

[Means for Solving the Problems] The problems to be solved by the present invention are as described above, and next, the means for solving the problems will be explained. That is, in a lubricating oil pump that is fixed by a mounting arm to a cylinder block of an engine or an underplate fixed to the lower surface of the cylinder block, in addition to the mounting arm of the lubricating oil pump, the lubricating oil is mounted below the main bearing cap. The pump and main bearing cap are connected by a central reinforcement mounting body.

[0005]

[Function] The central reinforcement mounting body 1 of the present invention has a mounting arm 2
With the parts 0 and 21 attached to the cylinder block 16, the third fixed part is attached to the mounting arms 20 and 21.
Since the lubricating oil pump P is fixed at three points, if the flatness is not correct at the three points, a gap will occur where some parts are floating. In such a case, the present invention uses a central reinforcing mounting body 1 that connects the centers by bending an iron plate into a U-shape. Therefore, the central reinforcing mounting body 1 itself has a certain degree of elasticity. The left and right mounting arms 20 and 21 are made of cast metal, since the lubricating oil pump P is made of cast metal, and have high rigidity, so they are not easily deformed. By fixing to the bottom surface of the block 16,
The central reinforcing mounting body 1 is bent to absorb gaps and overlapping portions formed in the central reinforcing mounting body 1.

[0006]

[Example] Next, an example will be explained. FIG. 1 is a side cross-sectional view showing the auxiliary equipment mounting mechanism of the engine of the present invention, FIG. 2 is a front cross-sectional view, FIG. A front view showing the state of the pump gear 4 and the lubricating oil pump P, FIG. 5 is a drawing showing the noise level in the conventional lubricating oil pump mounting mechanism, and FIG.
7 is a side view of only the lubricating oil pump P, and FIG. 8 is a perspective view of the central reinforcing mounting body 1.

The configuration of the main parts of the present invention will be explained with reference to FIGS. 1 and 2. Cylinder block 16 that constitutes the engine body
A block spacer 15 is interposed on the lower surface of the block spacer 15, and since the block spacer 15 is interposed, when the lubricating oil pump P is installed, there is a gap between the mounting arms 20, 21 and the cylinder block 16. Under plates 8 and 7 are interposed. And the mounting arms 20 before and after the lubricating oil pump P
- The part 21 is attached to the cylinder block 16 from below via the under plates 8 and 7. Conventionally, the lubricating oil pump P was attached to this attachment arm 20.
・It was only attached to the cylinder block 16 by 21. In contrast, in the present invention, the central reinforcing mounting body 1 is provided at the upper center of the lubricating oil pump P, and the central reinforcing mounting body 1 is attached to the lower surface of the main bearing cap 17 and the lower surface of the central mounting seat 18. This prevents deformation caused by the driving force.

Furthermore, the lubricating oil pump P deforms due to its driving force, and the pump gear 4 causes an apparent increase in backlash.Furthermore, such deformation causes the cylinder block 16 and the oil pan 9 to deform as shown in FIG. causes the deformation of
This results in amplification of the sound radiated from the entire engine. Therefore, by connecting the lubricating oil pump P with the main bearing cap 17 and the central reinforcing mounting body 1, vertical deformation of the lubricating oil pump P can be eliminated, backlash can be kept constant, and the mounting arm 20・Deformation of the cylinder block 16 and oil pan 9 can be avoided. The main bearing cap 17 is a component integrated with the cylinder block 16, protrudes from the cylinder block 16, and supports the crankshaft 12 by inserting a bearing metal into the main bearing cap 17. A balancer 10 is fixed to the crankshaft 12. 11 is the lower part of the piston rod. In addition to 17, the main bearing cap 19 is provided to support the crankshaft 12, but in the present invention, the main bearing cap 1 closest to the flywheel is
A central mounting seat 18 is provided on the lower surface of 7, a central reinforcing mounting body 1 is attached thereto, and the upper surface of the lubricating oil pump P is fixed to the lower surface of the central reinforcing mounting body 1. Lubricating oil pump P is pump case 2
6, a bearing/oil passage case 27, and an oil filter 2. Lubricating oil pump P composed of these
Attachment arms 20 and 21 from the pump case 26 part of
The mounting arms 20 and 21 are fixed to the lower surface of the cylinder block 16 via the under plates 8 and 7. 25 is a relief valve.

[0009]

[Effects of the Invention] Since the present invention is constructed as described above, the following effects can be achieved. Firstly, since there is no relative displacement between the lubricating oil pump and the engine body, there is no deviation in the gear pitch circles of both gears in the meshing direction, preventing fluctuations in gear backlash and reducing meshing noise. be. Secondly, the vibration mode of the oil pan on the side of the engine body becomes smaller on its outer periphery, and the sound radiated from the outer periphery is also reduced. Recently, the noise level of engines has been reduced, and the noise level has become considerably lower than before. At such a low noise level, the noise from the lubricating oil pump P and pump gear 4, which had not been noticed before, became annoying, and it became necessary to eliminate it. Thirdly, the durability of the drive gear 3 and pump gear 4 can be improved.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an auxiliary equipment mounting mechanism of an engine according to the present invention.

FIG. 2 is a front sectional view as well.

FIG. 3 is a diagram exaggerating the deflection state of a portion of the engine body 16.

FIG. 4 is a front view showing the states of the drive gear 3, pump gear 4, and lubricating oil pump P.

FIG. 5 is a drawing showing the noise level in a conventional lubricating oil pump mounting mechanism.

FIG. 6 is a front cross-sectional view without a central reinforcing attachment body.

FIG. 7 is a side view of only the lubricating oil pump P.

FIG. 8 is a perspective view of the central reinforcement mounting body 1.

[Explanation of symbols] 1. Central reinforcement mounting body 2 Combustion chamber 3 Drive gear 4 Pump gear 5 Lubricating oil pump shaft 9 Oil pan 16 Cylinder block 17 Main bearing cap 26 Pump case

Claims (1)

[Claims] Claim 1: In a lubricating oil pump fixed by a mounting arm to a cylinder block of an engine or an underplate fixed to the lower surface of the cylinder block, in addition to the mounting arm of the lubricating oil pump, a lubricating oil pump is mounted below the main bearing cap. , a lubricating oil pump mounting mechanism characterized in that the lubricating oil pump and the main bearing cap are connected by a central reinforcing mounting body.