WO2019167708A1

WO2019167708A1 - Fluid pump for ship and method for controlling same

Info

Publication number: WO2019167708A1
Application number: PCT/JP2019/005958
Authority: WO
Inventors: 泰柿元; 基輝和泉
Original assignee: 株式会社ジャパンエンジンコーポレーション
Priority date: 2018-03-02
Filing date: 2019-02-19
Publication date: 2019-09-06
Also published as: JP6546307B1; KR102316904B1; CN111788381B; KR20200105951A; CN111788381A; JP2019152148A

Abstract

A fluid pump for a ship, which is one aspect of the present invention, comprises a pump body that pressurizes and discharges a fluid by moving a piston in which pressure of hydraulic oil is used, a detection unit that detects a maximum movement amount of the piston in one fluid discharge, a control valve that selectively switches between an ON state in which hydraulic oil is supplied to the pump body and an OFF state in which the supply of hydraulic oil is stopped, and a control unit. The control unit derives a target movement amount of the piston in accordance with a fluid discharge amount required in one fluid discharge. On the basis of the difference between the target movement amount in the current fluid discharge and the maximum movement amount in the previous fluid discharge, the control unit calculates a time correction value for a valve ON time of the control valve, adds this time correction value to correct the valve ON time during the current fluid discharge, and controls the control valve so that the valve continues to be in an ON state for the corrected valve ON time.

Description

Marine fluid pump and control method thereof

The present invention relates to a marine fluid pump and a control method thereof.

Conventionally, a marine fluid pump for discharging a fluid such as fuel or water is applied to a marine diesel engine mounted on a marine vessel. For example, as a marine fluid pump, a fuel injection pump that pumps fuel to be injected into a cylinder to a fuel injection valve, and water is injected into a fuel flow passage from a discharge port of the fuel injection pump to a fuel injection valve injection port through a pipe. Examples include water injection pumps. Patent Document 1 describes a fuel injection pump that is driven and controlled by hydraulic fluid supplied via an electromagnetic valve.

In general, a marine fluid pump includes a piston in a state where the piston can reciprocate in the longitudinal direction, and pressurizes the fluid by moving the piston using the pressure of hydraulic oil supplied through a control valve. To discharge. The amount of fluid discharged by such a marine fluid pump changes in accordance with the amount of movement of the piston when the fluid is pressurized and discharged. For this reason, in a marine fluid pump, the movement amount of the piston is accurately controlled from the viewpoint of ensuring the accuracy required for the fluid discharge amount (for example, the fuel injection amount or water injection amount in a marine diesel engine). Is desired.

Japanese Patent No. 4176742

In order to accurately control the amount of movement of the above-described piston, in many cases, an opening adjustment type electromagnetic valve such as a servo valve or a proportional valve that can control the amount of hydraulic oil supplied with high accuracy by adjusting the opening. Is used as a control valve for a marine fluid pump. However, when an opening adjustment type electromagnetic valve is used as a control valve, generally, an actual measurement value of the piston movement amount is frequently measured during the fluid discharge period, and each time an actual measurement value of the piston movement amount is obtained. Since it is necessary to reflect the deviation from the target value in the adjustment of the opening degree of the control valve, the device configuration for accurately controlling the movement amount of the piston may be complicated, and the cost of the device may be expensive. In addition, the opening adjustment type solenoid valve is often vulnerable to foreign matter, and foreign matter is likely to be mixed in the environment where marine diesel engines operate. Solenoid valves may not be suitable.

The present invention has been made in view of the above circumstances, and is a marine fluid pump capable of accurately controlling the movement amount of a piston when pressurizing and discharging a fluid while suppressing an increase in cost. An object is to provide a control method thereof.

In order to solve the above-described problems and achieve the object, a marine fluid pump according to the present invention includes a pump body that pressurizes and discharges fluid by moving a piston using the pressure of hydraulic oil, A detection unit that detects the maximum movement amount of the piston in one discharge of the fluid, and an on state in which the hydraulic oil is supplied to the pump body and an off state in which the supply of the hydraulic oil is stopped are alternatively switched. The target movement amount of the piston is derived according to the control valve and the discharge amount of the fluid required for one discharge of the fluid, and the target movement amount derived at the time of the current discharge of the fluid and the previous time Based on the difference from the maximum amount of movement detected at the time of discharge, a time correction value of a valve on time, which is a time for turning on the control valve, is calculated, and the calculated time correction value is calculated. In consideration of this fluid The valve on-time is corrected at the time of output, characterized in that it comprises a control unit for controlling the control valve so as to continue said valve on-time after correction becomes the ON state.

In the marine fluid pump according to the present invention, in the above invention, the control unit derives a valve on basic time that is a valve on time of the control valve set according to the target movement amount of the piston. The valve on time during the current discharge of the fluid is corrected so as to be the sum of the valve on basic time and the time correction value.

Further, the marine fluid pump according to the present invention is the marine fluid pump according to the above invention, wherein the control unit has a data table indicating a correlation between the target movement amount of the piston and the valve on basic time of the control valve, The basic valve-on time correlated with the target movement amount derived at the time of fluid discharge is derived based on the data table.

Further, the marine fluid pump control method according to the present invention includes the pump body via a control valve that selectively switches between an on state in which hydraulic oil is supplied to the pump body and an off state in which the supply of the hydraulic oil is stopped. In a control method for a marine fluid pump that pressurizes and discharges fluid by moving the piston of the pump body by using the pressure of the supplied hydraulic oil and moving the piston, A target movement amount deriving step for deriving a target movement amount of the piston in accordance with a discharge amount of the fluid required by the discharge of the piston, and the target movement amount of the piston by the target movement amount deriving step and the previous time of the fluid Based on a difference from the maximum movement amount of the piston at the time of discharge, a time correction value calculation step for calculating a time correction value of a valve on time that is a time for which the control valve is in the on state. And a correction step for correcting the valve on time at the time of the current discharge of the fluid, taking into account the time correction value by the time correction value calculation step, and the valve on time after correction is continued. And a control step of controlling the control valve so as to be in an on state.

Further, the marine fluid pump control method according to the present invention is the above-described invention, wherein the correction step is a valve on basic time which is a valve on time of the control valve set according to the target movement amount of the piston. And the valve on time at the time of the current discharge of the fluid is corrected so as to be the sum of the valve on basic time and the time correction value.

Moreover, in the control method for a marine fluid pump according to the present invention, in the above invention, the correction step is based on a data table indicating a correlation between the target movement amount of the piston and the valve-on basic time of the control valve. Then, the valve-on basic time correlated with the target movement amount in the target movement amount derivation step is derived.

According to the present invention, it is possible to accurately control the movement amount of the piston of the marine fluid pump when pressurizing and discharging the fluid while suppressing an increase in cost.

FIG. 1 is a schematic diagram showing a configuration example of a marine fluid pump according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an on state and an off state of the control valve in the embodiment of the present invention. FIG. 3 is a flowchart showing an example of a control method for the marine fluid pump according to the embodiment of the present invention. FIG. 4 is a diagram for specifically explaining a marine fluid pump control method according to an embodiment of the present invention.

Hereinafter, preferred embodiments of a marine fluid pump and a control method thereof according to the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment. Also, the drawings are schematic, and it should be noted that the relationship between the dimensions of each element, the ratio of each element, and the like may differ from the actual ones. Even between the drawings, there are cases in which portions having different dimensional relationships and ratios are included. Moreover, in each drawing, the same code | symbol is attached | subjected to the same component.

(Configuration of marine fluid pump)
FIG. 1 is a schematic diagram showing a configuration example of a marine fluid pump according to an embodiment of the present invention. In this embodiment, the case where this marine fluid pump 10 is a water injection pump which inject | pours water into the fuel flow path of a marine diesel engine (not shown) is illustrated. The fuel flow passage of the marine diesel engine is a fuel flow passage from the discharge port of the fuel injection pump to the injection port of the fuel injection valve through the pipe, although not particularly shown. A fuel injection pump is a device that injects fuel through piping or the like to a fuel injection valve for injecting fuel into a cylinder of a marine diesel engine.

As shown in FIG. 1, a marine fluid pump 10 includes a pump body 1 that discharges water as an example of a fluid, a detection unit 6 that detects a maximum lift amount L _m (n) of a piston 2 of the pump body 1, A control valve 7 for supplying and discharging hydraulic oil to and from the pump body 1 and a control unit 11 for controlling the control valve 7 are provided. In FIG. 1, solid arrows indicate the flow of fluid such as hydraulic oil, and alternate long and short dash arrows indicate electrical signal lines.

The pump body 1 is a hydraulically driven pump device that discharges a fluid (water in the present embodiment) using the pressure of hydraulic oil. As shown in FIG. 1, the pump main body 1 includes a piston 2, a discharge chamber 3, a hydraulic oil chamber 4, and a water inlet 5.

The piston 2 is provided in the internal space of the pump body 1 so that it can reciprocate along its longitudinal direction. For example, the piston 2 includes a front portion 2a which is a piston portion on the water discharge side, a rear portion 2b which is a piston portion on the hydraulic oil receiving side, and a tapered portion 2c which is a portion between the front portion 2a and the rear portion 2b. Have. The piston 2 is formed in a rod shape so that the piston diameter of the front part 2a is smaller than the piston diameter of the rear part 2b. The tapered portion 2c is formed such that the piston diameter increases or decreases (decreases in FIG. 1) from the front portion 2a side toward the rear portion 2b side. The taper part 2c is used for detection of the maximum lift amount L _m (n) of the piston 2 by the detection part 6 described later.

The discharge chamber 3 is a space for temporarily storing water discharged from the pump body 1. As shown in FIG. 1, the discharge chamber 3 is configured to be a space that faces the end surface of the front portion 2 a of the piston 2 in the internal space of the pump body 1. The hydraulic oil chamber 4 is a space that receives hydraulic oil for operating the pump body 1. As shown in FIG. 1, the hydraulic oil chamber 4 is configured to be a space facing the end surface of the rear portion 2 b of the piston 2 in the internal space of the pump body 1. The water injection port 5 is for filling the discharge chamber 3 with water, and is provided in the pump body 1 so as to communicate with the discharge chamber 3. Water to be injected is supplied from the water injection port 5 to the discharge chamber 3 through piping of a water tank (not shown). Water is supplied (supplied) to the discharge chamber 3 through the water inlet 5 every time water is discharged by the pump body 1.

Further, as shown in FIG. 1, a water injection pipe 18 leading to the discharge chamber 3 is connected to the discharge port side of the pump body 1. The water injection pipe 18 is a pipe that guides the water discharged from the discharge chamber 3 of the pump body 1 to the fuel flow passage described above. On the other hand, a hydraulic oil flow passage 17 communicating with the hydraulic oil chamber 4 is connected to the hydraulic oil receiving side of the pump body 1.

The pump main body 1 having such a configuration pressurizes and discharges water to be discharged by moving the piston 2 using the pressure of the hydraulic oil supplied via the control valve 7. At this time, the pump main body 1 receives the hydraulic oil from the hydraulic oil flow passage 17 to the hydraulic oil chamber 4 via the control valve 7 when the control valve 7 is in an ON state in which the hydraulic oil is supplied to the pump main body 1. The pump body 1 moves (advances) the piston 2 so as to compress the discharge chamber 3 using the pressure of the received hydraulic oil. Thereby, the pump body 1 pressurizes the water in the discharge chamber 3 while blocking the communication between the discharge chamber 3 and the water injection port 5 with the piston 2. The pressurized water is discharged from the discharge chamber 3 into the water injection pipe 18.

On the other hand, when the control valve 7 is in an off state in which the supply of the hydraulic oil to the pump main body 1 is stopped, the pump main body 1 is the hydraulic oil after being used for the above-described water discharge (movement of the piston 2) (hereinafter, (Referred to as drain appropriately) is discharged from the hydraulic oil chamber 4 to the control valve 7 through the hydraulic oil flow passage 17. At this time, the piston 2 allows the drain in the hydraulic oil chamber 4 to flow through the hydraulic oil flow passage 17 and the control valve 7 by the repulsive force of an urging portion (not shown) such as a spring provided in the internal space of the pump body 1. Push to the side. As a result, the piston 2 is returned to the position before water discharge. The pump body 1 releases the compression (water pressurization) of the discharge chamber 3 by the piston 2.

The detection unit 6 detects the maximum lift amount L _m (n) of the piston 2 in one discharge of water by the pump body 1. As shown in FIG. 1, the detection unit 6 includes a detection processing unit 6a and an arithmetic processing unit 6b. The maximum lift amount L _m (n) is an example of the maximum movement amount of the piston 2 that moves in the direction in which the fluid is pressurized (upward in the present embodiment) in one discharge of the fluid by the pump body 1.

The detection processing unit 6a performs a detection process for detecting the maximum lift amount L _m (n). Specifically, as shown in FIG. 1, the detection processing unit 6 a is provided in the pump main body 1 so as to face the tapered portion 2 c of the piston 2. In the present embodiment, the pair of detection processing parts 6a are arranged so as to face each other with the taper part 2c interposed therebetween. The detection processing unit 6a detects (measures) the distance from the tapered portion 2c that changes due to the movement (lift) of the piston 2. The detection processing unit 6a performs such distance detection processing continuously or intermittently in time series, and each time, a signal indicating the obtained distance (hereinafter referred to as a distance detection signal as appropriate) is arithmetically processed. To the unit 6b.

The arithmetic processing unit 6b performs arithmetic processing for detecting the maximum lift amount L _m (n). Specifically, the arithmetic processing unit 6b sequentially receives the distance detection signals from the detection processing unit 6a in chronological order. The arithmetic processing unit 6b selects the distance detection signal that maximizes the distance and the distance detection signal that minimizes the distance from the plurality of distance detection signals received from the detection processing unit 6a. For example, the arithmetic processing unit 6b generates a distance detection signal at which the voltage reaches a peak when the distance between the detection processing unit 6a and the taper portion 2c becomes maximum and minimum during one discharge period of water by the pump body 1. Each distance detection signal is selected. The arithmetic processing unit 6b uses the distances between the selected distance detection signals (the distance between the detection processing unit 6a and the taper portion 2c) and the inclination angle of the taper portion 2c to generate water from the pump body 1. The maximum lift amount L _m (n) of the piston 2 in one discharge is calculated. Each time, the arithmetic processing unit 6 b transmits a signal indicating the obtained maximum lift amount L _m (n) (hereinafter, appropriately referred to as a lift amount detection signal) to the control unit 11.

The control valve 7 is a valve that switches between an ON state in which hydraulic oil for operating the pump body 1 is supplied to the pump body 1 and an OFF state in which the supply of hydraulic oil to the pump body 1 is stopped. For example, the control valve 7 is configured by an open / close electromagnetic valve that switches between opening and closing of the hydraulic oil flow passage. In the present embodiment, as shown in FIG. 1, the control valve 7 includes a supply flow path unit 7a, a discharge flow path unit 7b, and a drive unit 7c. Further, the control valve 7 includes a hydraulic oil pipe 15 leading to a pressure accumulating facility (not shown) for accumulating the hydraulic oil pressure, a drain pipe 16 leading to a tank (not shown) for collecting the hydraulic oil (drain), A hydraulic oil flow passage 17 communicating with the hydraulic oil chamber 4 of the pump body 1 is connected. As an example, FIG. 1 illustrates a state in which the hydraulic oil pipe 15, the drain pipe 16, and the hydraulic oil flow passage 17 are connected to the supply flow path unit 7 a of the control valve 7.

The supply flow path unit 7 a has a supply flow path 8 a for supplying hydraulic oil to the pump body 1 and a closed path 8 b for closing the drain pipe 16. The discharge flow path unit 7 b includes a discharge flow path 9 a for discharging drain from the pump body 1 and a closed path 9 b for closing the hydraulic oil pipe 15. The supply flow path unit 7a and the discharge flow path unit 7b are arranged so as to be adjacent to each other in a predetermined direction (lateral direction in FIG. 1), for example, as shown in FIG. The drive unit 7c is configured using an electromagnetic coil (solenoid coil) or the like. The drive unit 7c moves the supply flow path unit 7a and the discharge flow path unit 7b in the adjacent direction based on the valve control signal from the control unit 11, and thereby the supply flow path unit 7a and the discharge flow path unit 7b. Either of them is connected to the hydraulic oil pipe 15, the drain pipe 16, and the hydraulic oil flow passage 17. The control valve 7 selectively switches between the on state and the off state by the action of the drive unit 7c.

FIG. 2 is a diagram illustrating an on state and an off state of the control valve in the embodiment of the present invention. As shown in FIG. 2, the control valve 7 is switched from the OFF state to the ON state by connecting the supply flow path unit 7 a to the hydraulic oil pipe 15, the drain pipe 16, and the hydraulic oil flow passage 17. In the ON state, the supply flow path unit 7 a connects the supply flow path 8 a to the hydraulic oil pipe 15 and the hydraulic oil flow path 17 and connects the closed path 8 b and the drain pipe 16. As a result, the hydraulic oil pipe 15 and the hydraulic oil flow passage 17 are in communication with each other via the supply flow path 8a. The drain pipe 16 is closed by the closed path 8b. The hydraulic oil is supplied to the hydraulic oil chamber 4 of the pump body 1 through the hydraulic oil pipe 15, the supply flow path 8 a, and the hydraulic oil flow passage 17 that are in communication with each other. The hydraulic oil supplied to the hydraulic oil chamber 4 presses the piston 2 of the pump body 1 from the rear portion 2b side. The pump body 1 uses the pressure of the hydraulic oil to move the piston 2 to pressurize the water in the discharge chamber 3 at the front portion 2 a of the piston 2 and discharge the water into the water injection pipe 18. The supply of the hydraulic oil is continuously performed while the control valve 7 is on.

Further, as shown in FIG. 2, the control valve 7 is switched from the on state to the off state by connecting the discharge flow path unit 7b, the hydraulic oil pipe 15, the drain pipe 16, and the hydraulic oil flow passage 17. In the off state, the discharge flow path unit 7b connects the discharge flow path 9a with the drain pipe 16 and the hydraulic oil flow path 17, and connects the closed path 9b with the hydraulic oil pipe 15. As a result, the drain pipe 16 and the hydraulic oil flow passage 17 are in communication with each other via the discharge flow path 9a. The hydraulic oil pipe 15 is closed by the closed path 9b. As a result, the supply of hydraulic oil in the on state is stopped. In this case, the piston 2 is used for operating the hydraulic oil in the hydraulic oil chamber 4 (that is, for operating the pump main body 1) by a repulsive force of an urging portion (not shown) such as a spring provided in the internal space of the pump main body 1. The subsequent hydraulic oil) is pressed toward the control valve 7 side. The pressed hydraulic oil is discharged as drainage from the hydraulic oil chamber 4 through the hydraulic oil flow passage 17, the discharge flow passage 9a, and the drain pipe 16 that are in communication with each other as described above, and a predetermined tank (not shown). It is collected in As a result, the piston 2 is returned to the position before water discharge. The pump body 1 releases the compression (water pressurization) of the discharge chamber 3 by the front portion 2 a of the piston 2 and stops the discharge of water into the water injection pipe 18.

On the other hand, the control unit 11 shown in FIG. 1 controls switching of the control valve 7 between an on state and an off state. Specifically, the control unit 11 includes a CPU for executing various programs, a memory, a solenoid driving unit, and the like. The control unit 11 determines the target lift amount L _t (n) of the piston 2 of the pump body 1 according to the water discharge amount (water injection amount into the fuel flow passage) required for one discharge of water by the pump body 1. ) Is derived. The target lift amount L _t (n) is an example of the movement amount (target movement amount) of the piston 2 that is a target for the pump main body 1 to discharge the required discharge amount of fluid by one discharge. For example, the target lift amount L _t (n) is required for one discharge of the fluid by the pump body 1 because the equipment specifications such as the discharge capacity of the pump body 1 that discharges the fluid are known. It can be derived based on the discharge amount of the fluid.

The control unit 11 uses the target lift amount L _t (n) derived during the current discharge of water by the pump body 1 and the maximum lift amount L _m (n−1) detected by the detection unit 6 during the previous discharge. Based on the difference, a time correction value of the valve ON time of the control valve 7 is calculated. The valve on time is a time for which the control valve 7 is turned on as described above. The time correction value is a value (correction time) for correcting the valve ON time. In consideration of the calculated time correction value, the control unit 11 corrects the valve on time during the current discharge of water by the pump main body 1 so that the corrected valve on time continues and remains on. The control valve 7 is controlled.

In the present embodiment, the control unit 11 has a data table 11a as shown in FIG. The data table 11 a shows the correlation between the target lift amount L _t (n) of the piston 2 and the basic valve-on time of the control valve 7. The valve on basic time is the valve on time (theoretical valve on time in terms of equipment specifications) of the control valve 7 set according to the target lift amount L _t (n) of the piston 2. The data table 11 a includes a plurality of combinations of the target lift amount L _t (n) of the piston 2 and the valve on basic time of the control valve 7 that are correlated with each other. The control unit 11 derives the valve on basic time correlated with the target lift amount L _t (n) derived during the current discharge of water by the pump body 1 based on the data table 11a. The control unit 11 corrects the valve-on time during the current discharge of water by the pump body 1 so as to approach the sum of the derived valve-on basic time and the above-described time correction value.

(Control method for marine fluid pump)
FIG. 3 is a flowchart showing an example of a control method for the marine fluid pump according to the embodiment of the present invention. FIG. 4 is a diagram for specifically explaining a marine fluid pump control method according to an embodiment of the present invention. In the control method of the marine fluid pump 10 (see FIG. 1), each process of steps S101 to S104 shown in FIG. 3 is performed. At this time, as shown in FIG. 4, switching of the control valve 7 between the on state and the off state is controlled based on the valve control signal S1 from the control unit 11, and the pump body 1 discharges water through this control. The lift amount of the piston 2 at that time is controlled. Hereinafter, the current water discharge by the pump body 1 is referred to as “nth cycle water discharge”, and the previous water discharge by the pump body 1 is referred to as “n−1 cycle water discharge”. The next water discharge is referred to as “n + 1 cycle water discharge”. The control method of the marine fluid pump 10 will be described by exemplifying each process of steps S101 to S104 when the nth cycle of water discharge is performed.

As shown in FIG. 4, in the water discharge at the (n-1) th cycle, the control valve 7 switches from the OFF state to the ON state at the time T1 based on the valve control signal S1, and then the timing at the time T2. Switch from on to off. The time from time T1 to time T2 is the valve ON time ΔT3 of the control valve 7 in the water discharge of the (n-1) th cycle. As shown in FIG. 4, the valve on time ΔT3 is the basic valve on time of the control valve 7 set according to the target lift amount L _t (n−1) of the piston 2 in the water discharge of the (n−1) th cycle. This corresponds to the sum of ΔT1 and the time correction value ΔT2 calculated by the control unit 11 when the water is discharged in the (n-1) th cycle.

During the valve on time ΔT3, hydraulic oil is continuously supplied to the hydraulic oil chamber 4 of the pump body 1 via the control valve 7 and the like in the on state. The pump body 1 moves the piston 2 using the pressure of the supplied hydraulic oil, thereby pressurizing and discharging water. As shown in FIG. 4, the lift amount of the piston 2 increases with the passage of time from the time T1 when the control valve 7 is turned on, and the time from the time T2 when the control valve 7 is turned off. Decreases with progress. In this case, the maximum lift amount L _m (n−1) of the piston 2 in the water discharge of the (n−1) th cycle is the lift amount of the piston 2 at the timing of time T2, as shown in FIG. Detector 6 transmits a lift detection signal indicating the maximum lift L _{m (n-1)} detecting a maximum resultant lift L _{m (n-1)} to the control unit 11. The control unit 11 receives the lift amount detection signal from the detection unit 6 and holds the maximum lift amount L _m (n−1) indicated by the received lift amount detection signal as a parameter at the time of the subsequent n-th water discharge. To do.

Next, in the water discharge at the nth cycle, as shown in FIG. 3, the control unit 11 sets the target of the piston 2 according to the discharge amount of the fluid required for one discharge of the fluid by the pump body 1. A movement amount is derived (step S101).

In the present embodiment, in step S101, the control unit 11 derives the target lift amount L _t (n) of the piston 2 according to the water discharge amount required for the n-th water discharge.

Next, the control unit 11 determines the control valve 7 based on the difference between the target movement amount of the piston 2 in step S101 (target movement amount derivation step) and the maximum movement amount of the piston 2 at the previous discharge of fluid. A time correction value for the valve ON time is calculated (step S102).

In this embodiment, in step S102, the control unit 11 acquires and holds the target lift amount L _t (n) of the piston 2 derived in step S101 described above and the water discharge at the (n-1) th cycle. The difference (= L _t (n) −L _m (n−1)) from the maximum lift amount L _m (n−1) of the piston 2, that is, the lift amount deviation ΔL (n) shown in FIG. 4 is calculated. Based on the calculated lift amount deviation ΔL (n), the controller 11 calculates a time correction value ΔT12 in the nth cycle of water discharge. At this time, the control unit 11 lifts the lift based on the equipment specifications of the pump body 1, for example, the lift amount per unit time of the piston 2 that moves using the pressure of the hydraulic oil (amount of change over time of the lift amount). The quantity deviation ΔL (n) is converted into time (that is, converted into a time correction value ΔT12). The control unit 11 updates the time correction value ΔT2 in the water discharge of the (n−1) th cycle to the time correction value ΔT12 calculated in this way.

Next, the control unit 11 corrects the valve-on time of the control valve 7 during the current discharge of the fluid by the pump body 1 in consideration of the time correction value ΔT12 in step S102 (time correction value calculation step) (step S102). S103).

In the present embodiment, in this step S103, the control unit 11 derives the valve on basic time ΔT11 of the control valve 7 set according to the target lift amount Lt (n) of the piston 2. For example, the control unit 11 derives the valve-on basic time ΔT11 that correlates with the target lift amount Lt (n) in step S101 described above based on the data table 11a. The controller 11 adds the valve on basic time ΔT11 derived as described above and the time correction value ΔT12 calculated in step S102 to the valve on time ΔT13 of the control valve 7 in the water discharge of the nth cycle (= (T11 + ΔT12) is calculated (corrected).

Next, the control unit 11 controls the control valve 7 so as to be continuously turned on during the valve on-time ΔT13 after the correction in step S103 (correction step) (step S104). After executing step S104 (correction step), the control unit 11 returns to step S101 described above and repeats the processing steps after step S101.

In the present embodiment, in step S104, the control unit 11 transmits to the control valve 7 a valve control signal S1 (see FIG. 4) that instructs the valve ON time ΔT13 corrected as described above to continue to be in the ON state. To do. Thereby, the control part 11 controls switching of the ON state of the control valve 7 in the water discharge of the nth cycle, and an OFF state. As shown in FIG. 4, the control valve 7 switches from the off state to the on state at the timing of time T3 based on the valve control signal S1, and then switches from the on state to the off state at the timing of time T4. . The time from time T3 to time T4 is the valve-on time ΔT13 of the control valve 7 in the water discharge of the nth cycle.

During the valve on time ΔT13, hydraulic oil is continuously supplied to the hydraulic oil chamber 4 of the pump body 1 through the control valve 7 and the like in the on state. The pump body 1 moves the piston 2 using the pressure of the supplied hydraulic oil, thereby pressurizing and discharging water. As shown in FIG. 4, the lift amount of the piston 2 increases with the passage of time from the timing at time T3 when the control valve 7 is turned on, and the time from the timing at time T4 when the control valve 7 is turned off. Decreases with progress. In this case, the maximum lift amount L _m (n) of the piston 2 in the water discharge at the nth cycle is the lift amount of the piston 2 at time T4 as shown in FIG. Detector 6 transmits a lift detection signal indicating the maximum detected the lift amount L _{m (n),} the amount of the maximum resultant lift L _{m (n)} to the controller 11. The control unit 11 receives the lift amount detection signal from the detection unit 6 and holds the maximum lift amount L _m (n) indicated by the received lift amount detection signal as a parameter at the time of the subsequent n + 1 cycle water discharge.

Thereafter, in the water discharge of the (n + 1) th cycle, the difference between the target lift amount L _t (n + 1) of the piston 2 in the water discharge of the (n + 1) cycle and the maximum lift amount L _m (n) of the piston 2 in the water discharge of the n cycle ( Using the lift amount deviation ΔL (n + 1) which is = L _t (n + 1) −L _m (n)), the respective processing steps of steps S101 to S104 shown in FIG. 3 are performed. Thereby, switching of the control valve 7 between the ON state and the OFF state in the water discharge of the (n + 1) th cycle is controlled, and the lift amount of the piston 2 in the water discharge of the (n + 1) th cycle is controlled through this control. For example, as shown in FIG. 4, in the water discharge of the (n + 1) th cycle, the control valve 7 switches from the off state to the on state at the time T5 based on the valve control signal S1, and then the timing at the time T6. Switch from on to off. The time from time T5 to time T6 is the valve ON time ΔT23 of the control valve 7 in the water discharge of the (n + 1) th cycle. As shown in FIG. 4, the valve on time ΔT23 is equal to the basic valve on time ΔT21 of the control valve 7 set according to the target lift amount L _t (n + 1) of the piston 2 in the water discharge of the (n + 1) th cycle, and n + 1 This corresponds to the sum of the time correction value ΔT22 calculated by the control unit 11 when the water is discharged in the cycle.

During the valve on time ΔT23, the hydraulic oil is continuously supplied to the hydraulic oil chamber 4 of the pump body 1 through the control valve 7 in the on state. The pump body 1 moves the piston 2 using the pressure of the supplied hydraulic oil, thereby pressurizing and discharging water. As shown in FIG. 4, the lift amount of the piston 2 increases with the passage of time from the timing at time T5 when the control valve 7 is turned on, and the time from the timing at time T6 when the control valve 7 is turned off. Decreases with progress. In this case, the maximum lift amount of the piston 2 in the water discharge of the (n + 1) th cycle is the lift amount of the piston 2 at the timing of time T6 as shown in FIG. The detection unit 6 detects the maximum lift amount and transmits a lift amount detection signal indicating the obtained maximum lift amount to the control unit 11. The control unit 11 holds this maximum lift amount as a parameter at the time of water discharge in the subsequent cycle, as in the case of each of the water discharges in the (n-1) th cycle and the nth cycle described above.

By the control method of the marine fluid pump 10 as described above, the error between the target lift amount L _t (n) of the piston 2 and the maximum lift amount L _m (n) in the water discharge of the nth cycle is the n−1th cycle. It is reduced compared to the water discharge. Similarly, the error between the target lift amount L _t (n + 1) of the piston 2 and the maximum lift amount in the water discharge of the (n + 1) th cycle is reduced compared to the water discharge of the nth cycle.

As described above, in the marine fluid pump 10 and its control method according to the embodiment of the present invention, the control valve 7 for supplying the hydraulic oil for operating the pump body 1 is turned on to supply the hydraulic oil. And an open / close control valve that selectively switches off the supply of hydraulic oil, and the piston of the pump body 1 according to the fluid discharge amount required for one discharge of the fluid by the pump body 1 2 is derived, and the control valve 7 is turned on based on the difference between the target movement amount of the piston 2 during the current fluid discharge and the maximum movement amount of the piston 2 during the previous fluid discharge. The time correction value of the valve on time is calculated, and the valve on time of the control valve 7 at the time of the current fluid discharge is corrected in consideration of the calculated time correction value, and the valve on time after correction is continued. Control to turn on 7, and the piston 2 is moved using the pressure of the hydraulic oil supplied to the pump body 1 through the control valve 7, so that the piston 2 pressurizes the fluid and discharges it from the pump body 1. Like to do.

With the above configuration, complicated calculation processing such as adjusting the opening degree of the control valve by sequentially calculating the deviation between the measured value of the movement amount of the piston 2 and the target value during the fluid discharge period by the pump body 1 and the valve Even if the opening degree control is not performed, the valve ON time of the control valve 7 can be accurately corrected with a simple device configuration. For this reason, it is possible to accurately control the movement amount of the piston 2 when the fluid is pressurized and discharged while suppressing an increase in cost for the apparatus configuration. As a result, it is possible to ensure the accuracy of the fluid discharge amount required for the marine fluid pump 10 (for example, the fuel injection amount or water injection amount in the marine diesel engine).

In addition, since the above-described control valve 7 is an opening / closing type electromagnetic valve that is relatively resistant to foreign matter mixing, rather than an opening adjustment type electromagnetic valve that is relatively weak against foreign matter mixing, the marine diesel engine operates. The control valve 7 suitable for the marine fluid pump 10 installed in an environment, that is, an environment in which foreign matter is likely to be mixed, can be configured. As a result, it is possible to suppress failure and maintenance frequency due to foreign matter mixing into the control valve 7 of the marine fluid pump 10 in the marine vessel.

In the above-described embodiment, the water injection pump is exemplified as the marine fluid pump 10, but the present invention is not limited to this. For example, the marine fluid pump 10 may be a fuel injection pump that discharges (pressure feeds) fuel to the fuel injection valve, or may be a pump that discharges fluid other than fuel. That is, in the present invention, the type of fluid to be discharged is not particularly limited.

In the above-described embodiment, the control unit 11 in which the data table 11a indicating the correlation between the target movement amount of the piston 2 and the basic valve-on time of the control valve 7 is illustrated as an example. It is not limited. For example, the control unit 11 may be preliminarily set with an arithmetic expression, a calculation program, or the like that calculates the valve-on basic time of the control valve 7 based on the target movement amount of the piston 2.

In the above-described embodiment, the lift amount (the upward movement amount of the piston 2) is exemplified as the movement amount of the piston 2, but the present invention is not limited to this. In the present invention, the movement amount of the piston 2 may be any movement amount in the direction in which the fluid to be discharged is pressurized, and this direction is not particularly limited.

Further, the present invention is not limited by the above-described embodiment, and the present invention includes a configuration in which the above-described constituent elements are appropriately combined. In addition, other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the above-described embodiments are all included in the scope of the present invention.

As described above, the marine fluid pump and the control method thereof according to the present invention are useful for discharging fluids such as fuel and water in marine diesel engines, and in particular, the amount of movement of the piston when the fluid is pressurized and discharged. Is suitable for a marine fluid pump that can be controlled with high accuracy while suppressing an increase in cost, and a control method thereof.

DESCRIPTION OF SYMBOLS 1 Pump main body 2 Piston 2a Front part 2b Rear part 2c Tapered part 3 Discharge chamber 4 Hydraulic oil chamber 5 Water injection port 6 Detection part 6a Detection processing part 6b Calculation processing part 7 Control valve 7a Supply flow path unit 7b Discharge flow path unit 7c Drive part 8a Supply flow path 8b Closed path 9a Discharge flow path 9b Closed path 10 Marine fluid pump 11 Control section 11a Data table 15 Hydraulic oil pipe 16 Drain pipe 17 Hydraulic oil flow path 18 Water injection pipe S1 Valve control signal

Claims

A pump body that pressurizes and discharges fluid by moving the piston using the pressure of hydraulic oil;
A detection unit for detecting a maximum movement amount of the piston in one discharge of the fluid;
A control valve that selectively switches between an on state for supplying the hydraulic oil to the pump body and an off state for stopping the supply of the hydraulic oil;
A target movement amount of the piston is derived according to a discharge amount of the fluid required for one discharge of the fluid, and the target movement amount derived at the time of the current discharge of the fluid and a previous discharge. Based on the difference from the detected maximum movement amount, calculate a time correction value of the valve on time that is the time to turn the control valve in the on state, taking into account the calculated time correction value, A controller that corrects the valve on-time during the current discharge of the fluid, and controls the control valve so that the valve on-time after the correction continues and is in the on state;
A marine fluid pump comprising:
The control unit derives a valve on basic time which is a valve on time of the control valve set according to the target movement amount of the piston, and the valve on time at the time of the current discharge of the fluid is The marine fluid pump according to claim 1, wherein the marine fluid pump is corrected so as to be a time obtained by adding a valve on basic time and the time correction value.
The control unit has a data table indicating a correlation between the target movement amount of the piston and the valve-on basic time of the control valve, and is correlated with the target movement amount derived at the time of the current discharge of the fluid. The marine fluid pump according to claim 2, wherein the basic valve-on time is derived based on the data table.
The hydraulic oil is supplied to the pump body via a control valve that selectively switches between an on state for supplying the hydraulic oil to the pump body and an off state for stopping the supply of the hydraulic oil. In a control method for a marine fluid pump that pressurizes and discharges fluid by moving the piston of the pump body using pressure,
A target movement amount deriving step for deriving a target movement amount of the piston in accordance with a discharge amount of the fluid required for one discharge of the fluid;
A valve that is the time for which the control valve is turned on based on the difference between the target movement amount of the piston in the target movement amount derivation step and the maximum movement amount of the piston at the previous discharge of the fluid. A time correction value calculating step for calculating a time correction value of the on-time;
In consideration of the time correction value in the time correction value calculation step, a correction step of correcting the valve on time at the time of the current discharge of the fluid;
A control step for controlling the control valve so that the valve on-time after the correction continues and is in the on state;
A control method for a marine fluid pump, comprising:
The correction step derives a valve on basic time that is a valve on time of the control valve set according to the target movement amount of the piston, and sets the valve on time at the time of the current discharge of the fluid as the valve on time. 5. The marine fluid pump control method according to claim 4, wherein a correction is made so as to be a time obtained by adding a valve on basic time and the time correction value.
In the correction step, based on a data table indicating a correlation between the target movement amount of the piston and the valve-on basic time of the control valve, the valve ON that correlates with the target movement amount in the target movement amount derivation step. 6. The marine fluid pump control method according to claim 5, wherein a basic time is derived.