JPS6172812A - Lubricating oil pump - Google Patents

Abstract

PURPOSE:To prevent the occurrence of friction between a sleeve and a relief valve sliding within the sleeve and to improve reliability, by a method wherein a sleeve, made of a silicone alumi material, is inserted into or pressed in a valve hole part formed in the interior of a valve body. CONSTITUTION:A shaft 17, coupled to the driving part of an engine, exerts a rotary force on a drive gear 18 and a driven gear 19. In which case, lubricating oil, flowing through a strainer 13 and an oil passage 16, is fed through an oil passage 14 from a discharge port 15 to the engine. When a discharge oil pressure is increased, a relief valve 23 is moved leftward against the spring 24, and an outgoing passage 26 is opened. As a result, oil in an oil passage 14 is discharged through the outgoing passage 26 to the suction parts of two gears 18 and 19 to prevent excessive increasing of an oil pressure. In which case, a sleeve 22, in which the relief valve 23 is slidably located is formed by an alumi material, and is inserted into or pressed in a valve body 20.

Description

[Detailed Description of the Invention] [Objective of the Invention °] (Industrial Application Field) The present invention relates to a lubricating oil pump, and more specifically to a lubricating oil pump used in an internal combustion engine such as an automobile engine. be.

(Prior art) In lubricating oil pumps used in automobile engines,
Recently, light alloy cast products such as aluminum have been increasingly used for main components such as pump bodies for reasons of weight reduction. As an example of this type of lubricating oil pump, the one disclosed in Japanese Utility Model Application Publication No. 58-63308 has a shaft supported within an aluminum suspended pump body, a drive gear fixed to one end of the shaft, and a drive gear fixed to one end of the shaft. A pumping action is performed by a driven gear driven by a gear. The pump body is further integrally formed with a valve body that accommodates a relief valve. The relief valve is slidably disposed in a valve hole formed in the valve body, and acts to maintain the pump oil pressure at a set value.

(Problem to be solved by the invention) Conventionally, the valve body that is integrally formed with the pump body is made of a light alloy and is cast by casting, and the light alloy is usually made of aluminum or magnesium. . However, since aluminum and magnesium have low hardness, the valve hole formed inside the valve body wears out due to the sliding of the relief valve, which is usually made of iron material.As a result, the relief valve that slides in the valve hole becomes tilted, causing the relief There was a problem in that the valve could no longer maintain smooth sliding motion, and in some cases, foreign matter could get caught in the gap formed by wear and become locked.

Therefore, the technical object of the present invention is to improve the wear resistance of the sliding portion of the valve hole formed in the valve body.

[Structure of the invention]

(Means to solve the problem) The technical measures taken to solve the above technical problem are:
This involves inserting or press-fitting a high-silicon aluminum material into the valve hole formed inside the valve body.

(Function) By inserting or press-fitting a high-silicon aluminum material with excellent wear resistance into the valve hole where the relief valve slides, the wear resistance of the sliding portion of the valve hole is improved.

Therefore, the amount of wear on the valve hole that occurs as the relief valve slides is reduced, the relief valve does not tilt, ensuring smooth operation of the valve, and the valve lock phenomenon caused by wear is prevented. .

(Example) Hereinafter, an example embodying the present invention will be described based on the accompanying drawings.

A lubricating oil pump 10 shown in FIG. 1 has a pump body 11 made of light alloy aluminum.
A cover 12 also made of aluminum is fixed to 1,
Furthermore, an oil strainer 13 is disposed at the end of the cover 12. An oil passage 14 and a discharge port 15 are formed in the pump body 11, while an oil passage 16 is formed in the force bar 12. Further, a shaft 17 is supported inside the pump body 11, a drive gear 18 is fixed to one end of the shaft 17, and a driven gear 19 is engaged with the drive gear 18.

Now, a valve body 20 is integrally formed with the pump body 11, and a valve hole 2 is formed inside the body 20.
1, a pultruded hollow silicone aluminum sleeve 22 is inserted or press-fitted into the sleeve 22. A relief valve 23 is slidably disposed within the hollow sleeve 22, and the relief valve 23 is always urged rightward by the urging force of a spring 24. That is, the relief valve 23 is biased in the direction of cutting off communication between the oil inflow path 25 communicating with the oil passage 14 and the relief oil outflow path 26.

Incidentally, one end 24 of the spring is supported by a plug 25 that is threadedly connected to the left opening of the O-pulp hole 21 in the drawing.

Next, the operation of the lubricating oil pump 10 having the above configuration will be explained. The shaft 17 is connected to a driving part of the engine and transmits rotational force to a drive gear 18 and a driven gear 19. The lubricating oil flowing through the strainer 13 and the oil passage 16 is transferred to the oil passage 16 by the operation of both gears 18 and 19.
It is fed to the engine from the discharge port 15 via. When the discharge oil pressure supplied from the oil passage 14 to the discharge port 15 is low,
The relief valve 23 is pressed against the seat portion 22a formed in the sleeve 22 by the biasing force of the spring 24, and communication between the oil inflow path 25 and the relief oil outflow path 26 is cut off. When the discharge oil pressure increases and reaches a predetermined value, the relief valve 23 moves to the left in the figure against the biasing force of the spring 24 and opens the outflow passage 26. As a result, oil passage 14
The oil inside is discharged to the suction portions of both gears 18 and 19 through the outflow passage 26, thereby preventing an excessive rise in oil pressure.

The relief valve 23 and the sleeve 22 always slide, and due to the flow of oil from the inflow path 25 to the outflow path 26, the relief valve 23 slides at an angle, which tends to cause uneven wear.
Since the sleeve 22 inserted or press-fitted into the valve hole 21 is made of high-silicon aluminum material with excellent wear resistance, defects such as valve locking caused by wear are effectively prevented compared to ordinary die-cast aluminum material. Ru.

〔Effect of the invention〕

As a technical means to improve the wear resistance of the valve hole in which the relief valve slides, there is a method of using a cast iron insert member, but in this method, the aluminum valve body and the cast iron insert member are made of different materials. Because there is
Due to the difference in shrinkage rate, a mold is likely to occur at the boundary between the two parts.

According to the present invention, since the high-silicon aluminum material is made by infiltrating the aluminum base material with silicon, there are no boundaries and the above-mentioned mold does not occur. In addition, the cast iron insert member requires a wall thickness to ensure sufficient strength to withstand the pressure of Gui Cast, and the valve body requires a wall thickness so that the insert member can be inserted. Although the size and weight of the valve body increases, the technical means of the present invention prevents such an increase in size and weight of the valve body.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a lubricating oil pump according to the present invention, and FIG. 2 is an enlarged view of the main part (part A) of FIG. 1. 10... Lubricating oil pump, 11... Pump body, 2
0... Valve body, 21 Pulp hole, 22... High silicon aluminum sleeve, 23... Relief valve Fig. 1

Claims (1)

[Claims] In an oil pump, the valve body that houses the relief valve is integrally formed with the light alloy pump body.
A lubricating oil pump in which a high-silicon aluminum material is inserted or press-fitted into a valve hole formed inside the valve body.