JP2002174105A - Structure of oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the stress on a mounting portion due to vibration during high rotation and to improve the strength of the mounting portion. SOLUTION: In the structure of an oil pump in which an oil pump case communicating with a strainer having a suction part and a pipe part for oil is mounted on a crank lower case, and a pipe part is disposed in the longitudinal direction of the crank lower case, the pipe part consists of a pipe part on the case side where the pipe part is formed integrally with the oil pump case and a pipe part on the suction opening side connected to a suction part. The pipe part on the case side is disposed in the longitudinal direction of the crank lower case.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an oil pump, and more particularly to a structure of an oil pump for reducing the stress generated at a mounting portion due to vibration at high rotation and improving the strength of the mounting portion. is there.

[0002]

2. Description of the Related Art An oil pump is driven by the rotational force of a crankshaft of an engine, sucks oil in an oil pan, and supplies the oil to predetermined lubrication parts and cooling parts.

The structure of the oil pump is disclosed in
There is one disclosed in Japanese Patent Application Publication No. 994-185330.
The engine oil pump support structure disclosed in this publication supports a crankshaft on a main bearing constituted by a lower part of a half-skirt type cylinder block and a plurality of bearing caps, and is formed coaxially with the crankshaft. In the engine oil pump support structure in which the oil pump linked to the crankshaft is mounted on the front of the cylinder block, a bearing beam is provided to connect between multiple bearing caps, and the lower part of the oil pump is fixed to the bearing beam. The vibration in the axial direction of the crankshaft generated at the lower part of the pump is reduced.

[0004]

However, in the conventional oil pump and strainer mounting structure, as shown in FIGS.
14 is supported by a bearing cap 112 that is integral with the crank lower case 108.

[0005] The oil pump 116 is fixed to the lower surface of the crank lower case 108 by bolts 118.

A strainer 124 is mounted on an end of the oil pump 116, and is fixed to the oil pan 110 by a bolt 134 and a bracket 136.

At this time, the oil suction portion 120 of the strainer 124 is connected to the mounting portion 13 with the oil pump 116.
2, the vibration increases at the time of high rotation, and there is a disadvantage that an excessive stress is generated in the mounting portion 132.

Further, the crank lower case 108 and the bearing cap 112 are made of an aluminum material in order to reduce the weight.
At the time of high load, there is a disadvantage that the bearing portion is deformed and vibration noise is increased.

As a countermeasure for this, it is conceivable to increase the thickness of the bearing cap 112 or to change the material (for example, to cast iron). It is disadvantageous in nature and is hard to say.

[0010]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, an oil pump case communicating with a strainer having an oil suction part and a pipe part is mounted on a crank lower case. In the structure of the oil pump in which the pipe portion is disposed in the longitudinal direction, the pipe portion includes a case-side pipe portion formed integrally with the oil pump case and a suction-port-side pipe portion connected to the suction portion. The case-side pipe portion is disposed in the longitudinal direction of the crank lower case.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION
When arranging the case-side pipe part that is formed integrally with the oil pump case, arrange the case-side pipe part in the longitudinal direction of the crank lower case, and place the oil pump case mounting part close to the strainer suction part. As a result, the stress generated at the mounting portion due to vibration during high rotation is reduced, and the strength of the mounting portion is improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

1 to 4 show an embodiment of the present invention. 1 and 2, reference numeral 2 denotes an engine, 4 denotes a cylinder block, and 6 denotes a front differential case.

As shown in FIG. 2, the engine 2 includes a cylinder block 4, a cylinder head (not shown) mounted on the upper surface of the cylinder block 4, a crank lower case 8 mounted on a lower surface of the cylinder block 4, Oil pan 1 mounted on the lower surface of crank lower case 8
0.

A bearing cap 12 is provided integrally with the crank lower case 8, and a crankshaft 14 is supported by the bearing cap 12.

An oil pump 16 is fixed to the lower surface of the crank lower case 8 by oil pump fixing bolts 18 as shown in FIG.

A strainer 24 having an oil suction part 20 and a pipe part 22 is attached to an end of the oil pump 16 and is not fixed to the oil pan 10 by bolts. For this reason, conventional brackets and bolts have been eliminated.

Further, the pipe portion 22 is disposed in the longitudinal direction of the crank lower case 8, and the pipe portion 22 is connected to the case side pipe portion 22-1 formed integrally with the oil pump case 26 and the suction portion 20. And the case-side pipe portion 22-1 is disposed in the longitudinal direction of the crank lower case 8.

More specifically, as shown in FIG. 1, the pipe portion 22 is formed integrally with the oil pump case 26, and substantially in the longitudinal direction of the crank lower case 8 (the left-right direction in FIG. 1). A case-side pipe portion 22-1 disposed in parallel with a suction-side pipe portion attached to an end of the case-side pipe portion 22-1 and connected to the suction portion 20 in a diagonally downward direction. 22-2.

As shown in FIG. 2, the oil pump case 26 is attached to the lower surface on one end side of the crank lower case 8 as viewed from the axial direction of the crankshaft 14.
One end of the upper oil pan 10 is formed so as to bulge outward, and the pipe portion 22 of the strainer 24 is disposed so as to extend substantially at the center of the upper oil pan 10-1. The bottom surface of the upper oil pump case continuously formed on the side surface on the other end side of the upper oil pan 10-1 is formed to extend substantially to the center between the other end side and the oil pump case 26. A substantially central portion is connected to the lower oil pan 10-2. Since the lower oil pump case is formed so as to be offset toward one end, the upper oil pan 10-1 at the other end is formed.
A space is formed by the lower oil pan 10-2 and the front differential case 6 is disposed in this space. Also,
The lower oil pan 10-2 is connected to the crankshaft 14.
When viewed from the longitudinal direction, the oil pan 10-1 is connected to the upper oil pan 10-1 substantially at the center rear.

The case-side pipe portion 22-1 is
As shown in FIGS. 1 to 4, three first to third ribs 28-1 and 28-2 extending in the direction of the bearing cap 12.
28-3, and these first to third ribs 28-1 and 28-2
8-2 and 28-3 are fixed to the bearing cap 12 with rib fixing bolts 30.

At this time, the first to third ribs 28-
As shown in FIG. 3, 1, 28-2 and 28-3 are provided on the transmission-side crank lower case 8 to which a transmission case (not shown) is mounted, while the chain-side crank lower case 8 to which the oil pump case 26 is mounted. And attached to the bearing cap 12.

The first rib 28-1 is attached to the bearing cap 12 near the connecting portion between the oil pump case 26 and the case side pipe portion 22-1 by a fixing bolt 30, and the third rib 28-3 is connected to the oil pump case. A fixing bolt 3 is attached to a bearing cap 12 formed on an end surface opposite to the end surface of the crank lower case 8 to which the fixing bolt 26 is attached.
0, and the second rib 28-2 is attached to the bearing cap 12 disposed substantially at the center between the first rib 28-1 and the third rib 28-3. As shown in FIG. 3, these first to third ribs 28-1, 28-2, 28-3 have a pipe portion 22 side as a bottom surface and a mounting portion side with which a fixing bolt 30 is screwed as a top portion. It is formed in a substantially triangular shape.

For this reason, the bearing cap 12
As shown in FIG. 1, a total of four locations of the oil pump case 26 and the first to third ribs 28-1, 28-2, 28-3 are connected.

Further, as shown in FIGS. 1 and 2, a third rib 28 is provided near an attachment portion 32 for attaching the suction port side pipe portion 22-2 to an end of the case side pipe portion 22-1.
-3 is provided.

Next, the operation will be described.

When the oil pump 16 is mounted, the oil pump 16 is fixed to the lower surface of the crank lower case 8 by oil pump fixing bolts 18.

Then, the case-side pipe portion 22-1 of the pipe portion 22 is connected to the longitudinal direction of the crank lower case 8 (FIG. 1).
Of the first to third ribs 28 extending substantially in the direction of the bearing cap 12.
The case-side pipe portion 22-1 is fixed to the bearing cap 12 with the rib fixing bolts 30 using -1, 28-2, and 28-3.

The suction port side pipe portion 22-2 is mounted on the mounting portion 32 at the end of the case side pipe portion 22-1.

As a result, the mounting portion 32 of the oil pump case 26 can be brought close to the suction portion 20 of the strainer 24, and the stress generated in the mounting portion 32 due to vibration during high rotation can be reduced. , Mounting part 3
2 can be improved.

The case-side pipe portion 22-1 is
Three first to first extending in the direction of the bearing cap 12
It has third ribs 28-1, 28-2, 28-3, and these first to third ribs 28-1, 28-2, 28-3 are fixed to the bearing cap 12 by means of rib fixing bolts 30. Thus, the bearing cap 12 and the oil pump case 26 can be connected, and the support rigidity of the bearing cap 12 can be improved, which is practically advantageous.

Furthermore, the first to third ribs 28-1 and 28-1
-2 and 28-3 are attached to the bearing cap 12 provided on the transmission-side crank lower case 8 to which the transmission case is attached, with respect to the chain case-side crank lower case 8 to which the oil pump case 26 is attached. One end of the crank lower case 8 to which the oil pump case 26 is attached is connected to the other end of the crank lower case 8 and the oil pump case 26, and the case side pipe portion 22-1 is supported with both ends held. Since the side and the other end are connected by the oil pump case 26, the support rigidity of the bearing cap 12 can be improved.

Further, the case-side pipe portion 22-1
By providing the third rib 28-3 near the attachment portion 32 for attaching the suction port side pipe portion 22-2 to the end of the third rib 28-3 formed on the attachment portion 32, Bearing cap 1 to which rib 28-3 is attached
2 and the support rigidity of the strainer 24 can be improved.

The bearing cap 12 includes:
An oil pump case 26, first to third ribs 28-1,
28-2 and 28-3, the support rigidity can be easily improved without incurring a significant increase in weight and cost, and can be improved during high rotation and high load. The bearing deformation of the crankshaft 14, that is, the deformation of the bearing cap 12, can be reduced, which can contribute to the reduction of vibration noise.

Further, a strainer 2 having an oil suction part 20 and a pipe part 22 at an end of the oil pump 16 is provided.
By mounting 4, the oil pan 10 is not fixed to the oil pan 10 with bolts, and the conventional brackets and bolts can be eliminated, which can contribute to a reduction in the number of parts and cost.

It should be noted that the present invention is not limited to the above-described embodiment, and various application modifications are possible.

For example, in the embodiment of the present invention, the bearing cap 1 is attached to the case-side pipe portion 22-1.
Three first to third ribs 28-1 and 28-2 extending in the direction 2
8-2 and 28-3, and the first to third ribs 28 are provided.
-1, 28-2, and 28-3 are fixed to the bearing cap 12 with the rib fixing bolts 30.
The case-side pipe portion 42-1 is provided with a protrusion 44 extending in the direction of the bearing cap 12, and has a special configuration in which the protrusion 44 is pressed against the bearing cap 12 when the case-side pipe portion 42-1 is attached. It is also possible.

That is, the case-side pipe portion 42-1
Is provided slightly displaced on the bearing cap 12 side of the inner wall component, and when the case side pipe portion 42-1 is attached,
As shown in FIG.
2 to maintain the state in which the protrusion 44 is pressed against the bearing cap 12 by the amount of displacement of the case-side pipe portion 42-1.

Then, after the case-side pipe portion 42-1 is attached, the projection portion 44 can be pressed against the bearing cap 12, and the holding state of the case-side pipe portion 42-1 is strengthened. It is possible to reduce the stress generated at the mounting portion due to the vibration.

It should be noted that the case-side pipe portion 42-1 is brought into direct contact with the bearing cap 12 and the oil pan of the inner wall member without providing the protruding portion 44, thereby enhancing the holding state of the case-side pipe portion 42-1. It is also possible to adopt a special configuration for reducing the stress generated at the mounting portion due to the vibration during high rotation.

Further, it is also possible to adopt a special configuration in which a holding portion 52 for holding the suction portion 20 located at the distal end portion of the strainer 24 is provided.

That is, as shown in FIG.
4 is formed at the lower end of the suction part 20, and a concave part 52-2 having a shape matching the convex part 52-1 is formed inside the oil pan 10, and when the strainer 24 is attached, the suction part 52-1 is formed. 20 is fitted or brought close to the concave portion 52-2 inside the oil pan 10, and the swinging state of the suction portion 20 is changed by the holding portion 52 composed of the convex portion 52-1 and the concave portion 52-2. To maintain.

When vibration occurs in the suction portion 20 of the strainer 24, the convex portion 52-1 and the concave portion 52-2 are formed.
This can be solved by the fitting or close state of the holding portion 52, which is practically advantageous.

[0044]

As described above in detail, according to the present invention, the oil pump case communicating with the strainer having the oil suction portion and the pipe portion is attached to the crank lower case, and the pipe is provided in the longitudinal direction of the crank lower case. In the structure of the oil pump in which the parts are disposed, the pipe part is composed of a case side pipe part integrally formed with the oil pump case and a suction side pipe part connected to the suction part, and the case side pipe part is formed. Since the oil pump case is disposed in the longitudinal direction of the crank lower case, the mounting portion of the oil pump case can be brought close to the suction portion of the strainer, and the stress generated at the mounting portion due to vibration during high rotation can be reduced. Thus, the strength of the mounting portion can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional front view of an oil pump portion of an engine according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of an oil pump portion of the engine.

FIG. 3 is a bottom view of an oil pump portion of the engine, as viewed from an arrow 3 in FIG. 1;

FIG. 4 is a cutaway view of a main part taken along arrow 4 in FIG. 1;

FIG. 5 is a schematic sectional view of an oil pump portion of an engine showing another first embodiment of the present invention.

FIG. 6 is a schematic enlarged sectional view of an oil pump portion of an engine according to another second embodiment of the present invention.

FIG. 7 is a cross-sectional front view of an oil pump portion of an engine showing the prior art of the present invention.

FIG. 8 is a bottom view of the oil pump portion of the engine taken along line 8 in FIG. 7;

[Explanation of symbols]

 Reference Signs List 2 engine 4 cylinder block 6 front differential case 8 crank lower case 10 oil pan 12 bearing cap 14 crankshaft 16 oil pump 18 oil pump fixing bolt 20 suction part 22 pipe part 22-1 case side pipe part 22-2 suction port side pipe part Reference Signs List 24 Strainer 26 Oil pump case 28-1 First rib 28-2 Second rib 28-3 Third rib 30 Rib fixing bolt 32 Mounting part

Claims (5)

[Claims] 1. An oil pump structure, wherein an oil pump case communicating with a strainer having an oil suction portion and a pipe portion is attached to a crank lower case, and the pipe portion is disposed in a longitudinal direction of the crank lower case. Part is composed of a case side pipe part integrally formed with the oil pump case and a suction port side pipe part connected to the suction part, and the case side pipe part is arranged in the longitudinal direction of the crank lower case. Characteristic oil pump structure. 2. The oil pump structure according to claim 1, wherein the case-side pipe portion has a rib extending in a direction of a bearing cap, and the rib is fixed to the bearing cap. 3. A crank cap provided on a transmission-side crank lower case to which a transmission case is attached, with a rib being attached to a chain case-side crank lower case to which an oil pump case is attached. The structure of the oil pump described in 1. 4. The structure of the oil pump according to claim 2, wherein the rib is provided on a mounting portion of the case-side pipe portion. 5. The oil pump according to claim 1, wherein the case-side pipe portion has a protrusion extending in the direction of the bearing cap, and the protrusion is pressed against the bearing cap during mounting. Structure.