JPH11153015A - Lubricating oil degradation preventive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To add a lubricating oil degradation inhibitor to lubricating oil by slidingly contacting the lubricating oil degradation inhibitor with a member in a lubricating oil circulating passage. SOLUTION: In an internal combustion engine, an inside surface 54 of an inside ring 23 is abraded since an outside surface 52 of a crankshaft 18 contacts with a bearing 20, that is, the inside surface 54 of the inside ring 23. An inhibitor 60 is shaven by slidingly contacting with an outside surface 52 of the crankshaft 18 according to progress of abrasion of the inside surface 54 of the inside surface ring 23 since the inhibitor 60 is arranged so as to become the same plane as the inside surface 54 of the inside surface ring 23. Thus, since the inhibitor 60 is added to lubricating oil, the inhibitor can be added to the lubricating oil by the simple constitution. The degradation of the lubricating oil can be more accurately restrained since the inhibitor is added according to an abrasion degree corresponding to a degradation degree of the lubricating oil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a device for preventing deterioration of a lubricating oil.

[0002]

2. Description of the Related Art Lubricating oil is circulated in an internal combustion engine to lubricate a movable portion of the internal combustion engine and a supporting portion for supporting the movable portion. However, when lubricating oil or the like from the movable portion or the supporting portion of the internal combustion engine is mixed into the lubricating oil, the lubricating oil is deteriorated, and the lubricating characteristics of the lubricating oil are reduced. So, for example,
In Japanese Utility Model Application Laid-Open No. 62-195612, in a lubricating oil deterioration preventing device including a tank storing a lubricating oil deterioration preventing agent, by controlling the opening and closing of a solenoid valve connected to the tank according to an operation situation and an operation history. Lubricating oil deterioration inhibitors are added to the lubricating oil circulation path to suppress deterioration of the lubricating oil.

[0003]

However, in the lubricating oil deterioration preventing device disclosed in Japanese Utility Model Application Laid-Open No. 62-195612, the addition of the lubricating oil deterioration preventing agent is controlled in accordance with the operating conditions and operation history. The control is complicated.
Further, since an electromagnetic valve is used to add the lubricating oil, the engine configuration is complicated. Accordingly, an object of the present invention is to add a lubricating oil deterioration inhibitor to lubricating oil with a simple structure.

[0004]

According to a first aspect of the present invention, there is provided a lubricating oil for circulating a lubricating oil for lubricating a movable portion of an internal combustion engine or a supporting portion for supporting the movable portion. A lubricating oil deterioration preventing device comprising: a circulation path; and a lubricating oil deterioration preventing agent adding means for adding a lubricating oil deterioration preventing agent for preventing deterioration of the lubricating oil. Adds the lubricating oil deterioration inhibitor to the lubricating oil by sliding the lubricating oil deterioration preventing agent into contact with a member in the lubricating oil circulation path.

According to a second aspect of the present invention, in the first aspect, the lubricating oil deterioration preventing agent adding means makes the lubricating oil deterioration preventing agent slidably contact the movable portion. Therefore, the lubricant deterioration preventing agent is shaved by the movable part and added to the lubricant.

According to a third aspect of the present invention, in the second aspect of the invention, the lubricating oil deterioration inhibitor adding means includes the lubricating oil deterioration inhibitor according to the decrease in the viscosity of the lubricating oil. Make sliding contact with the movable part. Therefore, the lubricating oil deterioration inhibitor is shaved by the movable part according to the decrease in the viscosity of the lubricating oil, and is added to the lubricating oil.

According to a fourth aspect of the present invention, in accordance with the third aspect, the lubricating oil deterioration inhibitor adding means is configured to move the lubricating oil deterioration preventing agent according to a decrease in the pressure of the lubricating oil. Part to make sliding contact. Therefore, the lubricating oil deterioration inhibitor is shaved by the movable part in accordance with the decrease in the pressure of the lubricating oil, and is added to the lubricating oil.

According to a fifth aspect of the present invention, in accordance with the third aspect, the lubricating oil deterioration inhibitor adding means is provided with the lubricating oil deteriorating agent according to the degree of wear of the movable portion or the support portion. An inhibitor is brought into sliding contact with the movable part. Therefore, the lubricant deterioration preventing agent is shaved by the movable part according to the degree of wear of the movable part or the support part, and is added to the lubricating oil.

According to a sixth aspect of the present invention, in the second aspect, the lubricating oil circulation path further comprises a detachable member, and the lubricating oil deterioration inhibitor comprises the detachable member. The lubricating oil deterioration inhibitor adding means slides the lubricating oil deterioration preventing agent to a member in the lubricating oil circulation passage when the detachable member is attached to the lubricating oil circulation passage. Make contact. Therefore, the lubricating oil deterioration inhibitor is added to the lubricating oil every time the detachable member is attached to the lubricating oil circulation path.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a lubricating oil circulation path (hereinafter, circulation path) 10 through which lubricating oil is circulated in an internal combustion engine to which the lubricating oil deterioration prevention device of the present invention is applied. The circulation path 10 extends from a lubricating oil tank (hereinafter, tank) 12 for temporarily storing lubricating oil, and a lubricating oil pump (hereinafter, referred to as pump) for pumping the lubricating oil in the tank 12 into the circulation path 10 in order. , Pump) 14, a lubricating oil filter (hereinafter, filter) for filtering the lubricating oil discharged from the pump 14
16 is connected. Further, the circulation path 10 extending from the filter 16 includes a crankshaft 20 for supporting a crankshaft (see FIG. 2) 18 for sequentially transmitting the engine output to the wheels, a crankshaft 18 and a piston (not shown). , A transmission gear 23 for transmitting the power of the crankshaft 18 to, for example, a camshaft 32 described later, a piston and a piston attached to the piston. It is connected to a piston part 25 including a ring and a cylinder into which a piston is inserted, and returns to the tank 12, while on the other hand supports and guides a cylinder head 24, an intake valve (not shown) and an exhaust valve (not shown). To a valve lifter guide 26 for The valve lifter guide 26 is inserted into a valve lifter guide hole (not shown) formed in the cylinder head 24. Valve lifter guide 26
Is connected to the rocker shaft 28 and the rocker arm 30 and returns to the tank 12 on the one hand, and is connected to the camshaft 32 and the cam 34 and returns to the tank 12 on the other hand.

The connecting rod support shaft 22 is mounted on the crankshaft 18, the cam 34 is mounted on a camshaft 32, and is rotated together with the camshaft 32 in response to engine driving.
8, rotatably attached to the cam 34, and connects the cam 34 to the intake valve and the exhaust valve. Further, a lubricating oil filter 36 for filtering the circulation path 10 is attached to the tip of the circulation path 10 on the tank 12 side. Further, a first pressure regulating valve 38 is arranged in parallel with the pump 14, and the first pressure regulating valve 38 is provided when the pressure in the circulation path 10 downstream of the pump 14 becomes higher than a predetermined pressure. The lubricating oil discharged from the pump 14 is returned to the circulation path 10 on the downstream side of the pump 14. The second pressure regulating valve 4 is connected in parallel with the filter 16.
0, the second pressure regulating valve 40 is configured to supply the lubricating oil discharged from the pump 14 to the downstream side of the filter 16 when the pressure in the circulation path 10 downstream of the filter 16 becomes higher than a predetermined pressure. To the circulation path 10. In this specification, “upstream” and “downstream” are terms corresponding to the flow of lubricating oil.

A lubricating oil filling pipe (hereinafter referred to as a filling pipe) 42 for filling the tank 12 with lubricating oil is connected to the tank 12, and a leading end opening of the filling pipe 42 is closed by a filling pipe lid 44. . Further, a level gauge 46 for detecting the amount of lubricating oil in the tank 12 is inserted into the tank 12 from outside. Further, a discharge port 48 for discharging the lubricating oil to the outside is formed in the bottom wall of the tank 12, and the discharge port 48 is closed by a plug 50.

Next, a lubricating oil deterioration preventing device according to a first embodiment of the present invention will be described. The degree of deterioration of the lubricating oil increases with an increase in the degree of wear of the movable part of the internal combustion engine or the supporting part that supports the movable part. Therefore, in the first embodiment, an inhibitor is added to the lubricating oil according to the degree of wear of the movable part or the support part of the internal combustion engine.

FIG. 2 shows a lubricating oil deterioration preventing device according to the first embodiment. FIG. 3 is a perspective view of the crank bearing of the first embodiment. Note that the crank bearing illustrated in FIG. 2 is a cross-section taken along line II-II in FIG. Between the outer surface 52 of the crankshaft 18 which is a movable portion and the inner surface 54 of the crankshaft (hereinafter, bearing) 20 which is a support portion, the crankshaft 18 is provided.
A part (hereinafter referred to as a crankshaft circulation path) 56 of the circulation path 10 that receives the lubricating oil for lubricating the oil is formed. Accordingly, the outer surface 52 of the crankshaft 18 which is a sliding portion, ie, a movable portion, and the bearing 20 which is a sliding portion, ie, a supporting portion, are provided.
An oil film is formed between. The bearing 20 is provided with a lubricating oil hole 21, and the lubricating oil hole 21 is connected to a supply pipe 58 that is a part of the circulation path 10 that supplies lubricating oil to the crankshaft circulation path 56. It should be noted that the width of the crankshaft circulation path 56 shown in FIG. 2 is drawn wider than the actual width for easy understanding. Also, the bearing 20 is mounted on a table 27.
Supported by

The bearing 20 comprises an inner ring 23 made of, for example, white metal and an outer ring 25 made of, for example, steel. In the inner ring 23 of the first embodiment, an inhibitor accommodating hole (hereinafter, accommodating hole) 62 for accommodating a lubricating oil deterioration inhibitor (hereinafter, inhibitor) 60 for preventing deterioration of the lubricating oil is formed. The preventive agent 60 fills the entire inside of the receiving hole 62, and the surface of the preventive agent 60 facing the crankshaft circulation path 56 is flush with the inner surface 54 of the inner ring 23. The inhibitor 60 is a solid of various lubricant deterioration inhibitors, and is not dissolved by the lubricant in the crankshaft circulation path 56.

As shown in FIG. 4, the inhibitor 60 comprises a number of capsules 68 containing various liquid or solid deterioration inhibitors.
May be solidified. When the capsules are relatively large, the capsules may be unevenly distributed. Therefore, it is preferable that the capsules 70 are arranged and solidified as shown in FIG. The inhibitor 60 includes a metal detergent, an antioxidant, an ashless dispersant, an abrasion inhibitor, an ashless rust inhibitor, a viscosity index improver, a pour point depressant, an antifoaming agent, a corrosion inhibitor, and a friction modifier. and so on. Also, a connecting rod as a movable part of the internal combustion engine, a connecting rod support shaft as a support part, or a valve lifter guide as a movable part, a valve lifter guide hole as a support part, or a rocker arm as a movable part, a rocker shaft as a support part, or a cam as a movable part, a supporter It is also possible to select a valve lifter guide as a part, a piston as a movable part, a cylinder as a support part, a piston ring as a movable part, a cylinder as a support part, or a transmission gear as a movable part, and a transmitted gear as a support part.

Next, the operation of the first embodiment will be described. In the internal combustion engine, the inner surface 54 of the inner ring 23 is worn because the outer surface 52 of the crankshaft 18 contacts the bearing 20, that is, the inner surface 54 of the inner ring 23. In the first embodiment, since the preventive agent 60 is disposed so as to be flush with the inner surface 54 of the inner ring 23, the preventive agent 60 is moved to the outer surface of the crankshaft 18 with the progress of wear of the inner surface 54 of the inner ring 23. 52
And is scraped by sliding contact. Since the inhibitor 60 is thus added to the lubricating oil, according to the first embodiment, the inhibitor can be added to the lubricating oil with a simple configuration. Also,
According to the first embodiment, since the inhibitor is added in accordance with the degree of wear corresponding to the degree of deterioration of the lubricating oil, the deterioration of the lubricating oil can be more accurately suppressed. The area of the contact surface of the inhibitor 60 that contacts the outer surface 52 of the crankshaft 18 is determined based on the degree of deterioration of the lubricating oil corresponding to the degree of wear of the inner surface 54 of the inner ring 23. Specifically, the larger the degree of deterioration of the lubricating oil at a certain degree of wear of the inner surface of the bearing 20, the larger the area of the contact surface of the inhibitor 60. In addition, the preventive agent 60 is used for the inner ring 23.
The inner ring 23
When the bearings 20 are worn and the bearing 20 should be replaced, it is also when the inhibitor 60 should be replaced. Therefore, in the first embodiment, when the bearing 20 is replaced, the inhibitor 60 is replaced with a new inhibitor. For this reason, according to the first embodiment, there is no need to perform only an operation for replacing the inhibitor.

Next, a description will be given of a lubricating oil deterioration preventing device according to a second embodiment of the present invention. In the first embodiment, the inhibitor is added to the lubricating oil as the wear of the inner surface of the bearing progresses, so that it is not possible to add sufficient inhibitor to the lubricating oil to suppress the deterioration of the lubricating oil. There is. Therefore, in the second embodiment, a sufficient inhibitor is added to the lubricating oil to suppress the deterioration of the lubricating oil.

FIG. 6 shows a lubricating oil deterioration preventing device according to a second embodiment. The receiving hole 62 of the second embodiment is provided with the bearing 20, that is, the inner ring 23 and the outer ring 25 and the bearing 20.
Is formed so as to penetrate through the support 27 supporting the.
A cover bolt 64 is screwed into the accommodation hole 62 from outside the table 27. The lid bolt 64 is formed with a communication passage 29 that communicates the inside of the accommodation hole 62 with the outside air. A spring 66 is disposed as an urging means between the preventive agent 60 accommodated in the accommodation hole 62 and the cover bolt 64. The compressed spring 66 urges the inhibitor 60 toward the crankshaft 18.
The spring coefficient of the spring 66 is such that the urging force when the spring 66 is most compressed is the crankshaft circulation path 5 during the idling operation.
6 is selected to be equal to the pressure of undegraded lubricating oil. Other configurations in the second embodiment are the same as those in the first embodiment, and thus description thereof will be omitted.

Next, the operation of the second embodiment will be described. In an internal combustion engine, the pressure of the lubricating oil in the circulation path 10 increases as the engine speed increases. Therefore, the pressure of the lubricating oil in the crankshaft circulation path 56 (hereinafter, lubricating oil pressure) becomes lowest during the idling operation with the lowest engine speed. Further, as the degree of deterioration of the lubricating oil increases, the viscosity of the lubricating oil decreases, and the pressure of the lubricating oil in the circulation path 10 decreases. Further, in the second embodiment, as described above, the spring coefficient is selected such that the urging force of the spring 66 is equal to the pressure of the undegraded lubricating oil during the idling operation. Therefore, when the lubricating oil is not deteriorated, the urging force of the spring 66 is equal to or lower than the lubricating oil pressure in all the engine operations, so that the preventive agent 60 remains stored in the storage hole 62.

On the other hand, when the lubricating oil has deteriorated, the viscosity of the lubricating oil decreases and the lubricating oil pressure decreases. Therefore, when the lubricating oil deteriorates and the lubricating oil pressure becomes smaller than the urging force of the spring 66, the inhibitor 60 is pushed out from the housing hole 62 toward the outer surface 52 of the crankshaft 18, and the outer surface 5 of the crankshaft 18.
Touch 2. The inhibitor 60 is provided on the outer surface 52 of the crankshaft 18.
And is added to the lubricating oil. When the inhibitor 60 is added to the lubricating oil, the viscosity of the lubricating oil increases, and the lubricating oil pressure increases. When the increased lubricating oil pressure becomes equal to the urging force of the spring 66, the preventive agent 60 is not pushed toward the outer surface 52 of the crankshaft 18, and
The addition of the inhibitor 60 to the lubricating oil is completed.

Thereafter, each time the lubricating oil deteriorates and the viscosity of the lubricating oil decreases, the above operation is repeated. Therefore,
According to the second embodiment, a larger amount of the inhibitor can be added to the lubricating oil than in the first embodiment. Further, according to the second embodiment, the inhibitor is added to the lubricating oil in accordance with a decrease in the pressure of the lubricating oil, that is, an increase in the degree of deterioration. Therefore, deterioration of the lubricating oil can be suppressed more reliably.
Further, in the second embodiment, when the engine operation is stopped, the lubricating oil pressure becomes smaller than the urging force of the spring 66. That is, when the engine operation is stopped, the inhibitor 60
Are in contact with the outer surface 52 of the crankshaft 18. Thus, when the engine is started, the inhibitor 60 is added to the lubricating oil. Therefore, according to the second embodiment, the inhibitor can be added to the lubricant in proportion to the number of engine starts. Since it is preferable to add an amount of the inhibitor sufficient to recover the deterioration of the lubricating oil with a smaller spring elongation, it is preferable that the surface area of the inhibitor that is brought into contact with the outer surface of the crankshaft be larger. Further, when the inhibitor 60 is worn and should be replaced, the cover bolt 64 is used.
, A new inhibitor can be inserted into the accommodation hole 62.

Incidentally, in the second embodiment, the inhibitor 60
Each time is added in contact with the outer surface 52 of the crankshaft 18, the inhibitor 60 becomes shorter. Therefore, the lubricating oil pressure at which the inhibitor 60 is brought into contact with the outer surface 52 of the crankshaft 18 gradually decreases. That is, when the inhibitor 60 is added to the lubricating oil, the degree of deterioration of the lubricating oil gradually increases. In other words, the deterioration of the lubricating oil gradually progresses, and the degree of deterioration exceeds the allowable value. Therefore, a spring coefficient larger than the spring coefficient in the second embodiment is selected, and when the lubricating oil pressure becomes smaller than a predetermined pressure at an engine speed larger than the engine speed during idling operation, the inhibitor is changed to the lubricating oil. You may make it add.
By adding the inhibitor to the lubricating oil before the degree of deterioration exceeds the allowable value, it is possible to suppress the deterioration of the lubricating oil from exceeding the allowable value.

Next, a lubricating oil deterioration preventing device according to a third embodiment of the present invention will be described. It may be sufficient to add the inhibitor to the lubricating oil periodically. Therefore, in the third embodiment, the addition of the inhibitor to the lubricating oil can be performed regularly and easily.

FIG. 7 shows a filter used in the lubricating oil deterioration preventing device according to the third embodiment of the present invention. The filter 16 needs to be replaced periodically. Therefore, in the third embodiment, a filter is selected as the movable part, and a circulation path to which the filter is connected as the support part is selected. The filter 16 includes a generally annular filter element 72 for filtering foreign substances in the lubricating oil, and a housing 74 for accommodating the filter element 72. An outer surface 82 of the filter element 72 and an inner surface 78 of the housing 74 form a pre-filtration lubricating oil receiving portion (hereinafter, a pre-filtration receiving portion) 84 for receiving lubricating oil before filtration. On the other hand, an inner surface 76 of the filter element 72 and an inner surface 78 of the housing 74 form a filtered oil receiving portion (hereinafter referred to as a filtered receiver) 80 for receiving the filtered lubricating oil. An introduction hole 88 to which a circulation path 10 for introducing lubricating oil into the pre-filtration receiving portion 84 is connected is formed in an inner surface 78 of the housing 74 forming the pre-filtration receiving portion 84.
Is provided. Further, a discharge hole 86 to which the circulation path 10 for receiving the lubricating oil discharged from the post-filtering receiving portion 80 is provided in the inner surface 78 of the housing 74 forming the post-filtering receiving portion 80. Further, in the third embodiment, the prevention agent 60 is disposed so as to close the discharge hole 86. In addition,
Other configurations in the third embodiment are the same as those in the first embodiment or the second embodiment, and a description thereof will not be repeated.

Next, the operation of the third embodiment will be described. When the used filter is removed and the unused filter 16 is connected to the circulation path 10, the inhibitor 60 disposed in the discharge hole 86 is brought into sliding contact with the pipe 90 constituting the circulation path 10 to be destroyed, After the filtration, the inhibitor 60 is released to the receiving portion 80. Therefore, according to the third embodiment, the inhibitor can be regularly and easily added to the lubricating oil.

In the third embodiment, the filter is provided with an agent which can be broken by sliding friction. However, this does not limit the present invention. For example, the level gauge 46 and the tank 12 which are periodically attached and detached are provided. The plug 50 attached to the bottom of the tub and the filling pipe lid 44 for closing the filling pipe 42 for filling the lubricating oil may be provided with an inhibitor that can be broken by sliding friction.

[0028]

According to the first to sixth aspects of the invention, the lubricating oil deterioration inhibitor is added to the lubricating oil by sliding contact with a member in the lubricating oil circulation path. Therefore, the lubricating oil deterioration preventing agent can be added to the lubricating oil with a simple configuration in which the lubricating oil is brought into sliding contact with a member in the lubricating oil circulation path.

Further, according to the third to fifth aspects of the invention, the lubricating oil deterioration inhibitor is shaved by the movable part according to the decrease in the viscosity of the lubricating oil, and is added to the lubricating oil. The viscosity of the lubricating oil decreases as the lubricating oil deteriorates. Therefore,
According to the present invention, the lubricating oil deterioration inhibitor is added to the lubricating oil in accordance with the degree of deterioration of the lubricating oil, so that the deterioration of the lubricating oil can be more accurately suppressed.

Further, according to the fourth aspect of the invention, the lubricating oil deterioration inhibitor is shaved by the movable portion in accordance with the decrease in the lubricating oil pressure, and is added to the lubricating oil. The pressure of the lubricating oil decreases as the lubricating oil deteriorates. Therefore, according to the present invention, the lubricating oil deterioration inhibitor is added to the lubricating oil according to the degree of deterioration of the lubricating oil, so that the deterioration of the lubricating oil can be more accurately suppressed.

Further, according to the fifth aspect of the invention, the lubricating oil deterioration inhibitor is shaved by the movable part according to the degree of wear of the movable part, and is added to the lubricating oil. As the degree of wear of the lubricating oil increases, the degree of deterioration of the lubricating oil increases. Therefore, according to the present invention, the lubricating oil deterioration inhibitor is added to the lubricating oil according to the degree of deterioration of the lubricating oil, so that the deterioration of the lubricating oil can be more accurately suppressed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a lubricating oil circulation path of an internal combustion engine to which a lubricating oil deterioration preventing device of the present invention is applied.

FIG. 2 is a diagram showing a lubricating oil deterioration preventing device according to a first embodiment of the present invention.

FIG. 3 is a perspective view of a crank bearing.

FIG. 4 is a view showing a lubricant deterioration preventing agent in the lubricant deterioration preventing device according to the first embodiment of the present invention.

FIG. 5 is a view showing another form of a lubricant deterioration preventing agent in the lubricant deterioration preventing device according to the first embodiment of the present invention.

FIG. 6 is a view similar to FIG. 2, showing a lubricating oil deterioration preventing device according to a second embodiment of the present invention.

FIG. 7 is a view showing a lubricating oil filter used in a lubricating oil deterioration preventing device according to a third embodiment of the present invention.

8 is a diagram showing the lubricating oil filter of FIG. 6 connected to a lubricating oil circulation path.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Lubricating oil circulation path 12 ... Lubricating oil tank 16 ... Lubricating oil filter 18 ... Crankshaft 20 ... Crank bearing 56 ... Crankshaft circulation path 60 ... Lubricating oil deterioration inhibitor 62 ... Inhibitor accommodating hole 66 ... Spring

Claims (6)

[Claims] 1. A lubricating oil circulation path for circulating a lubricating oil for lubricating a movable portion of an internal combustion engine and a supporting portion for supporting the movable portion, and a lubricating oil deterioration preventing agent for preventing deterioration of the lubricating oil. A lubricating oil deterioration preventing device for adding a lubricating oil deterioration preventing agent, wherein the lubricating oil deterioration preventing agent slides the lubricating oil deterioration preventing agent on a member in the lubricating oil circulation path. A lubricating oil deterioration preventing device, wherein the lubricating oil deterioration preventing agent is added to the lubricating oil by contacting the lubricating oil deterioration preventing agent. 2. The lubricating oil deterioration preventing device according to claim 1, wherein the lubricating oil deterioration preventing agent adding means slides the lubricating oil deterioration preventing agent into contact with the movable portion. 3. The lubrication system according to claim 2, wherein said lubricating oil deterioration inhibitor adding means slides said lubricating oil deterioration preventing agent on said movable portion in accordance with a decrease in viscosity of the lubricating oil. Oil deterioration prevention device. 4. The lubricating oil according to claim 3, wherein the lubricating oil deterioration inhibitor adding means slides the lubricating oil deterioration inhibitor on the movable portion in accordance with a decrease in the pressure of the lubricating oil. Deterioration prevention device. 5. The lubricating oil deterioration preventing agent adding means brings the lubricating oil deterioration preventing agent into sliding contact with the movable portion according to the degree of wear of the movable portion or the support portion. The lubricating oil deterioration preventing device according to the above. 6. The lubricating oil circulation path further comprises a detachable member, wherein the lubricating oil deterioration inhibitor is attached to the detachable member, and the lubricating oil deterioration inhibitor adding means comprises a detachable member. The lubricating oil deterioration preventing device according to claim 2, wherein when the member is attached to the lubricating oil circulation passage, the lubricating oil deterioration preventing agent is brought into sliding contact with a member in the lubricating oil circulation passage.