JP3107307U - Hydraulic system in electronically controlled diesel engine - Google Patents

Abstract

A hydraulic system in an electronically controlled diesel engine capable of removing fine dust contained in hydraulic oil without affecting the operation of a solenoid valve or the like and the cleaning function of an automatic backwash filter.
A hydraulic system of a diesel engine in which a valve or the like is driven by hydraulic pressure, wherein the hydraulic system supplies a tank T, a hydraulic drive unit, and hydraulic pump in the tank to the hydraulic drive unit And an automatic backwashing filter 3 provided between the pump P and the hydraulic drive unit, and the automatic backwashing filter 3 has a filter unit that captures impurities in the hydraulic oil, and is captured by the filter unit. A filter for flushing the working oil, which has been washed away with impurities in the automatic backwashing filter 3, between the automatic backwashing filter 3 and the tank, is provided between the automatic backwashing filter 3 and the tank. A pipe 4 is provided, and a settling tank 10 for precipitating impurities contained in the hydraulic oil is interposed in the filter pipe 4.
[Selection] Figure 1

Description

The present invention relates to a hydraulic system in an electronically controlled diesel engine. Conventionally, fuel injection and valve opening / closing timing in a diesel engine have been controlled by rotation of a camshaft mechanically connected to a crankshaft. In recent years, electronically controlled diesel engines that control fuel injection and exhaust valve opening and closing timing by operating hydraulic oil pressurized by a crankshaft driven hydraulic oil high-pressure pump via an electromagnetic valve that is opened and closed by computer control have been developed. It has been developed and installed on ships. Such an electronically controlled diesel engine can control the fuel injection timing regardless of the rotation of the crankshaft, so that it can optimize the combustion state in all speed ranges, thereby improving fuel efficiency and reducing harmful exhaust gas components. The effect can be expected.
The present invention relates to a hydraulic system in such an electronically controlled diesel engine.

  As shown in FIG. 2, the hydraulic system in the electronically controlled diesel engine is supplied from a hydraulic oil sump tank T that stores hydraulic oil, a pump P that pumps hydraulic oil in the hydraulic oil sump tank T, and a pump P. The hydraulic drive part which operates a fuel-injection apparatus and an intake / exhaust valve with hydraulic oil is provided. The hydraulic drive unit includes a hydraulic unit 1 that pressurizes the hydraulic oil sent from the pump P, and an electromagnetic valve 2 that controls the flow of high-pressure hydraulic oil supplied from the hydraulic unit 1. The operation of the fuel injection device and the intake / exhaust valve is controlled by opening and closing. The hydraulic oil in the hydraulic oil sump tank T is configured to return from the pump P to the hydraulic oil sump tank T through the hydraulic unit 1 and the electromagnetic valve 2 in the hydraulic drive unit.

In an electronically controlled diesel engine, hydraulic oil is very high pressure, and if dust etc. is mixed in the hydraulic oil etc., even if the dust etc. is fine, it will cause malfunction or malfunction of the solenoid valve etc. It is very important to keep it clean. Usually, as shown in FIG. 2, an automatic backwash filter 3 is provided between the pump P and the hydraulic unit 1, and the automatic backwash filter 3 removes dust and the like. Has been done.
This automatic backwashing filter 3 is provided with a filter unit that removes dust and the like in the hydraulic oil inside, and supplies the hydraulic oil to the hydraulic unit 1 through the filter unit. When the filter unit detects dust clogging based on the pressure and the clogging occurs, the filter unit 4 has a function of washing away the filter unit dust by flowing hydraulic oil through the filter pipe 4, so-called backwashing function. Yes. For this reason, the hydraulic fluid supplied to the hydraulic unit 1 can be kept clean, and the amount of oil supplied to the hydraulic unit 1 can be reduced by clogging the filter unit without replacing the filter unit. The electronic control diesel engine can be operated stably for a long period of time.

However, since the hydraulic oil that has flowed into the filter pipe 4 is returned to the hydraulic oil sump tank T through the pipe, if the dust or the like that has flowed along with the hydraulic oil enters the hydraulic oil sump tank T, the dust or the like again There is a possibility of flowing in the piping together with the hydraulic oil, and the presence of such dust or the like reduces the life of the hydraulic oil. Therefore, a primary filter 5 is attached to the filter pipe 4 to remove dust and the like from the hydraulic oil. However, fine dust that cannot be removed by the primary filter 5 eventually returns to the hydraulic oil sump tank T. . If the primary filter 5 is a fine mesh filter, or if a finer filter than the primary filter 5 is provided as a secondary filter in the filter pipe 4, fine dust can be removed, but the working oil flowing through the filter pipe 4 can be removed. Since the resistance increases and the flow rate decreases, there arises a problem that the cleaning efficiency of the filter unit in the automatic backwashing filter 3 decreases.
The filter pipe 4 is connected to a drain line 6 that returns excess hydraulic oil to the hydraulic oil sump tank T among the hydraulic oil supplied to the solenoid valve 2. The hydraulic oil in the drain line 6 has a higher pressure than the hydraulic oil in the drain line 6, and when the hydraulic oil from the filter pipe 4 flows into the drain line 6, the flow of the drain line 6 is obstructed, which may adversely affect the operation of the electromagnetic valve 2.

  In view of the above circumstances, the present invention provides a hydraulic system in an electronically controlled diesel engine that can remove fine dust and the like contained in hydraulic oil without affecting the operation of a solenoid valve or the like and the cleaning function of an automatic backwash filter. For the purpose.

A hydraulic system in an electronically controlled diesel engine according to a first device is a hydraulic system of a diesel engine in which a valve and a fuel injection device are driven by hydraulic pressure. The hydraulic system includes a tank in which hydraulic oil is stored and a hydraulic valve. And a hydraulic drive unit that operates the fuel injection device, a pump that supplies hydraulic oil in the tank to the hydraulic drive unit, and an automatic backwash filter provided between the pump and the hydraulic drive unit The automatic backwashing filter has a filter unit that traps impurities in the hydraulic oil, and has a backwashing function that flushes impurities trapped in the filter unit with the hydraulic oil, A filter arrangement is provided between the washing filter and the tank so that the hydraulic oil from which impurities have been washed away in the automatic backwashing filter flows into the tank. It is provided, in the filter pipe, precipitation tank to precipitate impurities contained in the hydraulic fluid, characterized in that it is interposed.
The hydraulic system in the electronically controlled diesel engine according to the second device is characterized in that, in the first device, the filter pipe is provided in a separate system from a pipe for returning the hydraulic oil from the hydraulic drive unit to the tank.

According to the first device, since the working oil from which impurities have been washed out is precipitated and removed in the settling tank, only working oil that does not contain impurities can be returned to the tank. Therefore, it is possible to prevent the impurities removed by the automatic backwashing filter from being recirculated, and it is possible to suppress deterioration of the hydraulic oil due to the influence of the impurities. Moreover, since a sedimentation tank does not become flow resistance, it can prevent that the washing | cleaning effect of the filter unit in an automatic backwashing filter falls.
According to the second device, since the flow of hydraulic oil returning from the hydraulic drive unit to the tank does not deteriorate, it is possible to prevent the hydraulic drive unit from being adversely affected by providing the automatic backwash filter.

Next, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic explanatory diagram of a hydraulic system according to the present embodiment. In the same figure, the code | symbol code | symbol T has shown the tank for storing hydraulic fluid. The tank T is connected to a hydraulic unit 1 of a hydraulic drive unit in the electronically controlled diesel engine E by a pipe L, and hydraulic oil is supplied from the tank T to the hydraulic unit 1 of the hydraulic drive unit by a pump P interposed in the pipe L. Is configured to be sent.
The electronically controlled diesel engine E is configured such that the intake and exhaust valves and the fuel injection device are operated by hydraulic pressure, and the operation of the intake and exhaust valves and the fuel injection device is controlled by a hydraulic drive unit. The hydraulic drive unit includes a hydraulic unit 1 that pressurizes hydraulic oil, an electromagnetic valve 2 that controls the flow of high-pressure hydraulic oil supplied from the hydraulic unit 1, and a fuel injection device that uses hydraulic oil supplied from the electromagnetic valve 2. And a drive unit (not shown) for operating the intake / exhaust valve, and the operation of the drive unit, in other words, the operation of the fuel injection device and the intake / exhaust valve, is controlled by opening and closing the electromagnetic valve 2. The opening and closing of the electromagnetic valve 2 is controlled by a control means such as a computer.
For this reason, if the pump P is operated and the hydraulic oil is sent to the hydraulic unit 1 of the hydraulic drive unit, the hydraulic oil is pressurized by the hydraulic unit 1, and the pressurized hydraulic oil is hydraulically driven via the electromagnetic valve 2. Thus, the intake / exhaust valve and the fuel injection device can be operated by the hydraulic oil, and the operation timing can be controlled by the opening / closing of the electromagnetic valve 2, in other words, the control means.

As shown in FIG. 1, an automatic backwash filter 3 is provided in a pipe L between the pump P and the hydraulic unit 1. The automatic backwash filter 3 includes a filter unit that captures impurities such as iron powder due to wear in the hydraulic oil.
For this reason, if the hydraulic oil is sent to the hydraulic unit 1 by the pump P, impurities can be removed from the hydraulic oil by the filter unit of the automatic backwash filter 3, and thus the purified hydraulic oil can be put in the hydraulic unit 1. it can.

Moreover, the automatic backwashing filter 3 has a backwashing function for washing the filter unit. The backwashing function detects the clogging of the filter unit based on the differential pressure between the inlet and outlet of the filter unit, and when the clogging occurs, the hydraulic oil is passed through the filter unit in the reverse direction. This is a function that can wash away dust from the filter unit. The automatic backwashing filter 3 is provided with a discharge port for discharging only the hydraulic oil (hereinafter referred to as cleaning oil) from which the dust of the filter unit has been washed away when the backwashing function is activated. The filter pipe 4 communicated with the tank T is connected.
For this reason, even if impurities are accumulated in the filter unit of the automatic backwash filter 3 by continuously operating the electronically controlled diesel engine E, in other words, by circulating the hydraulic oil in the hydraulic system, With the backwashing function, dust in the filter unit can be washed away to eliminate clogging of the dust, and the working oil from which the dust has been washed away, that is, the washing oil, can be flowed toward the tank T through the filter pipe 4.

Next, the configuration of the filter pipe 4 that is a feature of the hydraulic system of the present embodiment will be described.
As shown in FIG. 1, a primary filter 5 is interposed in a filter pipe 4 communicating between the discharge port of the automatic backwashing filter 3 and the tank T, and between the primary filter 5 and the tank T. Is provided with a sedimentation tank 10.
The primary filter 5 is a normal filter that scrapes impurities in the cleaning oil.
The sedimentation tank 10 is a tank for storing hydraulic oil in the interior and for removing impurities from the stored hydraulic oil, and in the filter tank 4 when the backwash function is activated. The hydraulic oil is stored in excess of 6 times the amount of cleaning oil supplied. A pipe 4 a that communicates between the primary filter 5 and the precipitation tank 10 is connected to the lower part of the precipitation tank 10, and a pipe 4 b that communicates between the precipitation tank 10 and the tank T is connected to the precipitation tank 10. In the state where the cleaning oil is not supplied to the filter pipe 4 at the upper part, the filter pipe 4 is disposed at a position above the oil level of the working oil in the settling tank 10.

  For this reason, the cleaning oil that has flowed into the filter pipe 4 flows into the settling tank 10 after impurities are removed by the primary filter 5. Then, the oil level of the hydraulic oil stored in the settling tank 10 rises according to the amount of the flowing cleaning oil, and when the oil level reaches the position of the pipe 4b, the hydraulic oil in the cleaning tank 10 is Then, it is supplied from the sedimentation tank 10 to the tank T through the pipe 4b.

Here, since the cleaning oil is supplied to the lower part of the precipitation tank 10, the cleaning oil does not flow directly into the pipe 4b. Moreover, since the amount of the hydraulic oil accommodated in the precipitation tank 10 is 6 times or more the amount of the cleaning oil supplied to the filter pipe 4 when the backwash function is activated, the precipitation tank 10 Even if the cleaning oil flows in, a large flow does not occur in the sedimentation tank 10, and the hydraulic oil located in the lower part of the sedimentation tank 10 does not flow into the pipe 4b. Therefore, among the hydraulic oil stored in the sedimentation tank 10, only the hydraulic oil located at the upper part thereof flows into the tank T.
Since only the washing oil from the automatic backwash filter 3 flows into the settling tank 10, the working oil in the settling tank 10 is normally kept in a non-flowing state, and fine impurities that could not be removed by the primary filter 5. Even so, it can be removed from the hydraulic oil by precipitation. Then, among the hydraulic oil stored in the sedimentation tank 10, the hydraulic oil located in the upper part is a clean hydraulic oil from which impurities have been removed. Only clean hydraulic fluid that is not included can be returned.

Therefore, if the filter pipe 4 is configured as described above, the impurities trapped in the automatic backwash filter 3 can be reliably removed from the hydraulic oil by the primary filter and the sedimentation tank 10, and the impurities are removed and cleaned. Since only the hydraulic oil can be returned to the tank T, impurities once trapped can be prevented from recirculating in the hydraulic system, and deterioration of the hydraulic oil due to the influence of impurities can be suppressed.
In addition, since the sedimentation tank 10 only stores hydraulic oil and does not become flow resistance when the cleaning oil flows from the automatic backwash filter 3 to the filter pipe 4, the cleaning effect of the filter unit in the automatic backwash filter 3. Can be prevented from decreasing.

  As shown in FIG. 1, the filter pipe 4 is a separate system from the hydraulic unit 1 and the electromagnetic valve 2 of the hydraulic drive unit, and pipes 6 to 8 for returning the hydraulic oil from the drive unit to the tank T. It is possible to prevent the flow of hydraulic oil returning from the hydraulic drive unit to the tank T from being deteriorated by the flow of cleaning oil. Therefore, even if the automatic backwash filter 3 is provided in the pipe L, it is possible to prevent an adverse effect on the operation of the electromagnetic valve 2 and the like of the hydraulic drive unit.

It is a schematic explanatory drawing of the hydraulic system of this embodiment. It is a schematic explanatory drawing of the conventional hydraulic system.

Explanation of symbols

1 Hydraulic Unit 2 Solenoid Valve 3 Automatic Backwash Filter 4 Filter Piping 10 Sedimentation Tank P Pump T Tank

Claims (2)

A hydraulic system of a diesel engine in which a valve and a fuel injection device are driven by hydraulic pressure, the hydraulic system including a tank that stores hydraulic oil, a hydraulic drive unit that operates the valve and the fuel injection device by hydraulic pressure, A pump for supplying hydraulic oil in the tank to the hydraulic drive unit, and an automatic backwash filter provided between the pump and the hydraulic drive unit,
The automatic backwash filter is
It has a filter unit that captures impurities in the hydraulic oil, and has a backwashing function to wash away impurities trapped in the filter unit with the hydraulic oil,
Between the automatic backwash filter and the tank, there is provided a filter pipe for flowing hydraulic oil that has washed out impurities in the automatic backwash filter to the tank,
A hydraulic system in an electronically controlled diesel engine, characterized in that a settling tank for precipitating impurities contained in hydraulic oil is interposed in the filter pipe. 2. The hydraulic system for an electronically controlled diesel engine according to claim 1, wherein the filter pipe is provided in a separate system from a pipe that returns hydraulic oil from the hydraulic drive unit to the tank. 3.

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