JP2006002690A - How to maintain engine oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil maintenance method for an engine having excellent workability and a small oil discard amount.
SOLUTION: The base number A at the start of oil use is measured and the base number B of the oil is measured when a predetermined time has elapsed after the start of oil use in order to determine the timing and amount of oil to be supplied to the engine. In addition, oil is replenished inside the engine, and the base number C after replenishment is measured to obtain the base number deterioration rate B / A and the base number recovery rate C / B. The subsequent oil replenishment amount and replenishment timing are determined from the rate and the oil replenishment amount.
[Selection] Figure 1

Description

  The present invention relates to an engine oil maintenance method for determining a replenishment timing and a replenishment amount of oil to an engine.

  For general cogeneration engines and automobile engines, various oils are used to reduce friction between the components that make up the engine, cool the engine body, and also ensure airtightness of cylinders, etc. To do. The oil is oxidized as the engine operating time increases, and the base number decreases. In addition, sludge due to friction of the engine members accumulates and the oil performance gradually decreases. For this reason, it is usually necessary to change the oil according to the operating time of the engine or after a lapse of a predetermined time after oil filling.

  The existing oil maintenance method drains all residual oil from an oil pan etc. and adds new oil when the operation time that requires oil replacement is reached. Addition of new oil was performed by replenishing oil separately from the oil tank, or by appropriately replenishing oil when the remaining oil in the oil pan was low.

  On the other hand, some conventional oil maintenance methods are improved with respect to existing oil replacement methods, and have a configuration in which a tank for discharging residual oil is retained and oil is automatically replaced ( Patent Document 1).

The above-mentioned conventional technology is intended to automate the oil change operation of the oil pan while suppressing the deterioration of the oil at the oil supply source when the oil in the oil supply source is automatically supplied to the engine oil pan by the electric pump. Is. In the present apparatus, the oil supply source includes, for example, a first tank and a second tank. Each of the first tank and the second tank is provided with a breather device and is hermetically sealed. The oil pan and the first tank are provided with oil amount detection means. The first oil outlet passage provided in the first tank and the second oil outlet passage provided in the second tank are connected to an oil pan via an electric pump.
Further, a waste oil inlet passage for discharging waste oil from the oil pan to the first tank is provided from the oil pan to the first tank. The first oil outlet passage, the second oil outlet passage, and the waste oil inlet passage are provided with passage opening / closing means. Based on the measurement result of the oil amount detection means provided in the oil pan and the first tank, the control means causes the passage opening / closing means and the electric pump to operate in cooperation.

  When it is detected that the amount of oil in the oil pan is less than the specified amount, the control means controls the driving of the passage opening / closing means and the electric pump, and supplies oil from the first tank until the oil pan reaches the specified amount. To do. This supply is performed only from the first tank until the first tank is empty. When the first tank is empty, the control means controls the passage opening / closing means to discharge oil from the oil pan to the first tank. When the oil pan is emptied, the control means drives and controls the passage opening / closing means and the electric pump to supply oil from the second tank until the oil pan reaches a specified amount.

As described above, in the conventional apparatus, since a plurality of tanks are used as the oil supply source, a large amount of oil can be distributed and accommodated in a small capacity tank. In addition, the time for using up the oil in the small-capacity oil tank is short, and the time for contacting the air inside the tank before the tank becomes empty is also short. Therefore, oil deterioration due to oxidation is suppressed. Since the oil in the second tank is not used while the oil in the first tank is consumed, no air flows into the second tank during that period, and deterioration due to oxidation is suppressed.
In addition, since the switching between the first tank and the second tank is automatically performed, it is not necessary to manage the oil change time, and the troublesome oil change work by manual operation becomes unnecessary. Furthermore, since the empty first tank is reused as a waste oil tank, it is not necessary to prepare a separate waste oil tank.

Japanese Patent Laid-Open No. 9-100711 [0007] to [0015]

However, in the above-described conventional apparatus, since all the oils held in the first tank and the oil pan are replaced at the time of maintenance, the oil replacement cost for that is high.
Also, it takes time to drain oil when changing oil. Moreover, gas engine heat pumps, gas engine cogeneration, and the like are often installed on the rooftop of a building or the like, and it takes time to carry replacement oil to the rooftop and further transport waste oil to the ground. Moreover, it is necessary to dispose of a large amount of oil. As described above, in the conventional oil changing method, there is a certain limit in improving the oil changing work efficiency.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an oil maintenance method for an engine that is excellent in workability and has a small amount of discarded oil.

(Characteristic means 1)
In the engine oil maintenance method according to the present invention, the base number A at the start of use of the oil is measured in order to determine the amount of oil to be supplied to the engine and the replenishment timing, and a predetermined time has elapsed after the start of use of the oil. Then, the base number B of the oil is measured, the oil is replenished inside the engine, the base number C after the replenishment is measured, and the base number deterioration rate B / A and the base number recovery rate C / B is obtained, and the subsequent oil replenishment amount and replenishment timing are determined from the deterioration rate and recovery rate of the oil and the oil replenishment amount.

(Function and effect)
The base number of oil is a value that indicates the content of an antioxidant that generally neutralizes oxidized oil. The higher the value, the more resistant to oxidative degradation and the better the cleanliness.
The installation environment and operating conditions of the engine are often different from each other, and the oil maintenance method is considered to vary depending on the engine. Therefore, in the oil maintenance method of the present invention, paying particular attention to the base number of the oil, the engine is actually operated to grasp the deterioration rate of the oil base number and the recovery rate of the base number when the oil is replenished. . Here, the deterioration rate is the ratio of the base number after use for a predetermined time to the oil base number at the start of use, and the recovery rate is the ratio of the base number after oil replenishment to the base number after use for the predetermined time. It is.

The time to perform oil maintenance must be before the oil is completely degraded. That is, it is necessary to perform oil maintenance before the base number drops to the oil replacement reference value that is the allowable minimum value of the oil base number. In this regard, in the method of the present invention, since the deterioration rate and the recovery rate are grasped, the time for oil maintenance can be determined appropriately. In particular, when long-life oil is used, by setting the oil maintenance interval as appropriate, it is possible to maintain the oil only by replenishing the oil decrease without discarding the oil used until then. .
As described above, according to the oil maintenance method of the present invention, it is possible to greatly reduce the labor of oil maintenance and reduce the amount of discarded oil, thereby performing efficient oil maintenance.

(Characteristic means 2)
In the engine oil maintenance method according to the present invention, when replenishing the oil, a predetermined amount is replenished, and for each replenishment of the predetermined amount, the replenished oil amount and the base number after replenishment are measured, Alternatively, the recovery rate of the base number with respect to the replenishment amount may be obtained.

(Function and effect)
As in this configuration, when oil is replenished, it is preferable to replenish a predetermined amount, and for each replenishment of the predetermined amount, measure the replenished oil amount and the base number after replenishment.
That is, the base number is recovered by replenishing oil, but at this time, the oil replenishment amount and the base number recovery rate are not necessarily in a proportional relationship. For example, when half of the planned oil replenishment amount is replenished, the base number recovery rate is not necessarily half of the total recovery rate. This is because the replenished new oil recovers the base number, but also contributes to the recovery of the oxidation of the oil, so the effect of the replenished new oil does not contribute to the recovery of the base number. Because there is no.

  Therefore, when oil is replenished, for example, a fixed amount is replenished, and the correlation between the replenishment amount and the base number recovery rate is accurately grasped. As a result, the oil replenishment amount for recovering the desired base number can be easily obtained during the next oil maintenance. Furthermore, it is not necessary to restore the base number to the maximum at the next oil maintenance, and it is sufficient to restore the base number at the next time to the extent that the base number does not fall below the oil replacement standard value at the next oil maintenance. In some cases. In such a case, if the correlation between the oil replenishment amount and the base number recovery rate is grasped as in the present invention, more planned oil maintenance can be performed.

(Characteristic means 3)
The engine oil maintenance method according to the present invention obtains a reference characteristic curve indicating the relationship between the engine operation time and the base number of the oil, sets a maintenance time for replenishing the oil in advance, and operates the engine. After starting, the base number of the oil after a predetermined time shorter than the maintenance time is measured, and compared with the base number on the reference characteristic curve at the predetermined time, the base number of the engine decreases. It is characterized in that the maintenance time is corrected based on the tendency of the base number to decrease.
(Function and effect)
Usually, if the engine is the same type, the oil base number lowering characteristics and the like are often approximated. However, in reality, the optimal oil maintenance method varies from engine to engine depending on the installation environment and operating conditions. Therefore, as in the present invention, by measuring the degree of decrease in the base number of the oil after a certain period of use and grasping the difference from the reference characteristics of the same type engine, the reference characteristics are corrected and the next oil replenishment timing is determined. It is possible to make an optimal oil maintenance plan for each engine.

(Characteristic means 4)
The engine oil maintenance method according to the present invention is characterized in that only oil replenishment is performed every predetermined time so that the base number of oil is maintained at a value larger than an oil replacement reference value that requires oil replacement. .
(Function and effect)
With the oil maintenance method of the present invention, the oil base number is maintained at a value larger than the oil replacement reference value, so that the oil lubrication performance and the like can be satisfactorily exhibited. In addition, since the oil maintenance operation only replenishes oil, there is no need to perform complicated oil discharge operation and subsequent disposal. Further, since no oil is generated and the oil can be used efficiently, the running cost of the engine can be reduced, and an environment-friendly oil maintenance method can be provided.

(Overview)
The engine oil maintenance method of the present invention is mainly a method for determining the amount and timing of oil replenishment to the engine. In this method, the target engine for oil maintenance is actually operated for a predetermined time, and new oil is replenished. At that time, it is intended to grasp how the base number of the oil fluctuates and predict the oil replenishment timing or the amount of oil replenishment after that, so that it can be used for the oil maintenance plan. is there. The oil maintenance method of the present invention will be described below with reference to the drawings.

(Oil characteristics)
FIG. 1 shows the relationship between the engine operating time and the oil base number (FIG. 1 (a)) and the relationship between the engine operating time and the oil amount (FIG. 1 (b)) when a general engine is operated. Indicates. Here, the base number is a value indicating one of various characteristics of the oil, and means a value indicating the content of an antioxidant that neutralizes the oxidized oil. It can be said that the higher this value is, the higher the resistance to oxidation deterioration and the higher the cleanliness.
As is apparent from FIG. 1A, the base number decreases in a curved line asymptotically approaching the horizontal axis as the engine operating time increases. At this time, when the predetermined time has elapsed after the start of engine operation, the oil replacement reference value is below. The oil change reference value is the lowest base number that the oil should have.
On the other hand, as is clear from FIG. 1B, the engine operation time and the oil amount are in a substantially linear relationship, and the oil amount decreases as the engine operation time increases. In general engine maintenance, when the base number reaches the oil replacement reference value, the entire amount of engine oil is replaced.

(First oil maintenance method)
In the present embodiment, an example in which the gas engine is operated using a specific type of engine oil for a gas engine of a specific type of gas heat pump will be described. As the engine runs, oil is consumed and the base number decreases. In any engine, there is a correlation between the oil consumption and the decreasing tendency of the base number. Such engine-specific correlation can be obtained as representative data by operating the target engine in advance and actually measuring it.
In reality, however, the tendency of the oil consumption or base number to decrease varies depending on the assembly error inherent to the engine, the difference in the engine operating environment, and the like. The present invention provides an oil maintenance method so that optimum engine maintenance can be performed in accordance with such individual engine operating conditions.

(Measurement of deterioration rate of base number)
FIG. 2 shows how the oil base number changes when the oil maintenance method of the present invention is used. First, add new oil to the engine until it reaches the specified oil level. The oil base number at this time is indicated by point A. Thereafter, the engine is actually operated, and after a predetermined time, the base number is measured. The base number at this time is B point. The reason why the base number decreases from the point A to the point B is that the oil comes into contact with exhaust gas components present in the engine and is oxidized.
It is preferable that the time between AB is as long as possible because the tendency of the base number to decrease can be known accurately. This period is set in accordance with, for example, a normal maintenance period. From these two base values, the base oil deterioration rate B / A is determined. The values A and B used for the calculation are values from the oil change reference value.

As shown in FIG. 1 (a), the base number decreases in a curved line while the inclination is reduced with the engine operating time. However, FIG. 2 shows how the base number decreases linearly. In order to plan for oil maintenance, there is no particular problem even with such a straight line display. Rather, making a maintenance plan with such an approximation sets the oil change time to a safer side, that is, the normal oil maintenance period is longer than the measurement period between AB. Therefore, the predicted value of the base number after the point B, which is obtained by extending the straight line AB as it is, is always smaller than the actual base value that decreases in a curved line.

  In addition, as the set time between AB is shortened, the base value is measured in a steep region of the actual decrease curve, so the slope of the decrease in base number becomes steeper. Conversely, the longer the operation time between AB is set, the smaller the base value decrease gradient becomes. However, it is closer to the actual base number lowering tendency and the base number lowering tendency can be accurately predicted when the interval between AB is set longer.

  Some common gas engines, for example, have a total operating time of about 30,000 hours for overhaul. In such an engine, the oil maintenance cycle is preferably about 10,000 hours. Oils in recent years have improved performance, and there are oils with a drivable period of 15000 hours as seen from the base number. When such oil is used, there is no problem even if the maintenance cycle is set to 10,000 hours. By the way, with a normal gas engine, it takes about 5 years to reach a total operating time of 10,000 hours.

(Measurement of recovery rate of base number)
In the oil maintenance method of the present invention, the work to be performed at the time of maintenance is mainly to replenish new oil so that the amount of oil becomes a specified level. The new oil is replenished before the base number reaches the oil change standard value. For maintenance, only refilling with new oil is performed, and oil is not removed during use. Oil replenishment is performed until a predetermined oil level is reached. As shown in FIG. 2, the base number of the oil is recovered to some extent by the replenishment. The base number after recovery is indicated by C point. C / B at this time is defined as a base number recovery rate.

As described above, by knowing the base number deterioration rate B / A and the recovery rate C / B and the oil replenishment amount, it is possible to plan the subsequent maintenance time and the oil replenishment amount.
By using this method, for example, the amount of oil to be replenished during the oil maintenance period is set to a small amount within a range that falls within a predetermined level, and the oil amount is set to the minimum level when the engine overhaul period is reached. Replenishment can also be performed. By replenishing in this way, efficient oil maintenance becomes possible, for example, the amount of oil used and the amount of oil discarded can be kept to a minimum.

When oil is replenished, it is preferable to replenish a predetermined amount, and measure the replenished oil amount and the base number after replenishment for each replenishment of the predetermined amount.
That is, in FIG. 2, the base number has recovered from point B to point C by replenishing oil, but at this time, the oil replenishment amount and the base number recovery rate are not necessarily in a proportional relationship. For example, in the process from point B to point C, the base number does not always become (B + C) / 2 when the replenishment amount reaches half. This is because the replenished new oil restores the base number, but also contributes to the restoration of oxidation.

  Therefore, when oil is replenished, it is preferable to replenish, for example, a fixed amount while confirming that the base number has reached the D point and the E point as shown in FIG. As a result, it is possible to accurately know the correlation between the oil replenishment amount and the recovery of the base number, so that the oil replenishment amount for recovering the desired base number can be determined during the next oil maintenance. it can. Furthermore, it is possible to perform more planned oil maintenance, such as determining the oil replenishment amount to restore the base number to the extent that the base number does not fall below the oil replacement reference value at the time of oil maintenance ahead. Become.

(Another embodiment)
In the oil maintenance method of the above-described embodiment, an oil maintenance plan is made based on the relationship between the operation time obtained by actually operating the engine and the base number. On the other hand, in the method according to this embodiment, as shown in FIG. 3, a typical relationship between the operation time and the oil base number is previously grasped as a reference characteristic curve in advance for the engine. Then, the engine is actually operated, and the difference between the reference characteristic curve and the actual operation data is obtained, and an oil maintenance plan is made.

  As shown in FIG. 3, the oil base number at the start of operation is point A. The oil base number decreases in a curve with the operation of the engine, and when the time t1 elapses, the oil base number decreases to the oil replacement reference value that is the lowest allowable value. Normally, the operation is not performed until the oil base number drops to the oil replacement reference value, and the oil is replaced or replenished at a maintenance time tm before that. The setting of the maintenance time tm can be arbitrarily determined at any stage before reaching t1.

  Even if the engine type is the same, the oil base number reduction mode does not necessarily match the reference characteristic curve depending on the use environment and operating conditions. Therefore, in order to recognize the difference from the reference characteristic curve, the base number when t time has elapsed from the start of operation is measured. For example, as shown in FIG. 3, it is desirable that this time be about 10% to 15% of tm, which is the initial oil maintenance time. For example, if the engine requires oil maintenance every 10,000 hours, it is set to 1000 to 1500 hours. The longer this time is set, the more accurate the grasp of the base number lowering characteristic. However, the original purpose of predicting the subsequent base number lowering characteristic by actual operation for a short time is diminished. In addition, if the set time is too short, the accuracy of prediction becomes low.

  As shown in FIG. 3, in the reference characteristic curve, the base number after operation for a predetermined time is B1. On the other hand, in this embodiment, the base number obtained as a result of actual operation was B2. Assuming that the engine operation mode is the same after this, it is considered that the state in which the base number value after the actual operation is better than the value of the reference characteristic curve continues.

  For example, the decrease in the base number is predicted as follows. First, the base number correction coefficient K = B2 / B1 is obtained using B1 and B2. The values of B1 and B2 are again values from the oil change reference value. The correction coefficient K is multiplied by the above-described maintenance time tm to obtain a new maintenance time tm1. Then, the M1 point is provided at a position corresponding to the new operation time tm1 which has the same base number as the M point on the reference characteristic curve. In other words, in FIG. 3, the region after B1 in the reference characteristic curve is replaced with a straight line extending from B2 to M1 to predict a downward trend in base number.

  When the engine operating time reaches tm1, it is only necessary to fill the new oil to the specified oil level. At this time, as described above, by adding a predetermined amount of new oil, the relationship between the amount of added oil and the degree of recovery of the base number can be grasped, so that the next oil maintenance time can be predicted. The replenishment amount can be determined.

  As described above, according to the oil maintenance method of the present invention, it is possible to predict the decrease in the oil base number for each engine by the operation for a predetermined time after the operation is started. As a result, an efficient oil maintenance plan up to the engine overhaul can be made. Furthermore, since the method of the present invention only replenishes oil during oil maintenance, the amount of discarded oil is extremely small and the environment is saved. It can be said that this is a consideration method.

(Example)
An embodiment according to the oil maintenance method of the present invention will be described with reference to FIGS. FIG. 5 shows the configuration of the engine used. An oil pan 2 is provided at the lower part of the engine body 1 and filled with engine oil 6. The oil pan 2 is connected to the reservoir tank 3 by an oil communication pipe 5. Reserve oil 7 is stored in the reservoir tank 3, and the oil pan 2 and the reservoir tank 3 communicate with each other through a reserve passage 4 for equalizing both pressures. Oil supply to the engine is performed through an oil supply port 8 provided in the reservoir tank 3.

  FIG. 4 shows the difference in oil consumption when oil maintenance is performed by an existing method and when the method of the present invention is performed. In the case of the existing method, 40 liters of new oil is used as the initial filling amount. Thereafter, 40 liters of fresh oil is used for each of the first and second replenishments. The operation time until the engine overhaul was set to 30000 hours, and the oil maintenance time was set to 10,000 hours. The oil consumption accompanying the operation of the engine was 2.0 cc / hour. At the time of the first replenishment and the second replenishment, 20 liters of residual oil was generated, which was discarded. As is clear from FIG. 4, in the existing method, the amount of new oil used was 120 liters, and the waste oil produced was 40 liters.

On the other hand, in the case of the method of the present invention, the initial filling amount of oil was 40 liters, but the oil used in the first replenishment and the second replenishment was 20 liters. No oil was discarded during replenishment. As a result, in the method of the present invention, the amount of new oil used may be 80 liters, and no waste oil was produced.
As described above, according to the oil maintenance method of the present invention, the oil consumption is extremely small and no waste oil is generated. Therefore, efficient and environmentally friendly oil maintenance is possible.

  The oil maintenance method of the present invention can be applied to various engines such as gas engines and gasoline engines used in general cogeneration and automobiles, and diesel engines, etc., and has excellent oil maintenance work efficiency and a large amount of oil waste. It can be used as a reasonable oil maintenance method.

Diagram showing changes in oil base number and oil amount The figure which shows the concept of the oil maintenance method which concerns on this invention The figure which shows the concept of the oil-maintenance method which concerns on another embodiment. The figure which shows the oil usage-amount in an Example Schematic diagram showing the structure of the engine

Explanation of symbols

A Base number of oil at the start of use B Base number of oil when a predetermined time has elapsed after start of use B / A Base rate deterioration rate C / B Base number recovery rate

Claims (4)

To determine when and how much oil will be charged to the engine
Measure the base number A at the start of use of the oil,
After the start of use of the oil, when a predetermined time has elapsed, the base number B of the oil is measured, and the engine is refilled with oil,
The base number C after the replenishment is measured to obtain the base number deterioration rate B / A and the base number recovery rate C / B.
An engine oil maintenance method for determining a subsequent oil replenishment amount and a replenishment timing from the oil deterioration rate and recovery rate and the oil replenishment amount.   When replenishing the oil, a predetermined amount is replenished, and for each replenishment of the predetermined amount, the replenished oil amount and the base number after replenishment are measured to obtain a base number recovery rate with respect to the oil replenishment amount. Item 2. The engine oil maintenance method according to Item 1. Obtain a reference characteristic curve showing the relationship between the engine operating time and the base number of the oil, and set a maintenance time for replenishing the oil in advance,
After starting the engine, measure the base number of the oil after a predetermined time shorter than the maintenance time,
By comparing with the base number on the reference characteristic curve at the predetermined time, to determine the tendency of the base number of the engine to decrease,
An engine oil maintenance method for correcting the maintenance time based on a tendency of the base number to decrease.   An oil maintenance method for an engine that only replenishes oil every predetermined time so that the base number of the oil is maintained at a value greater than an oil change reference value that requires oil change.

Images