JP2015048919A - Drive control device for electromagnetic valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive control device for an electromagnetic valve capable of improving control accuracy during an actual valve opening period of an electromagnetic valve by acquiring the actual valve opening period of the electromagnetic valve correctly.SOLUTION: Valve closing timing tCL of a fuel injection valve is detected, valve opening timing tOP is estimated based on the valve closing timing tCL, and a valve opening command signal SDCTL of the fuel injection valve is output based on the valve opening timing tOP. A time point when the valve opening command signal SDCTL is turned off, that is valve closing operation time Toff corresponding to the time from valve closing command timing tIE to the valve closing timing tCL, is calculated, and the valve opening timing tOP of the fuel injection valve is estimated based on valve opening command time Ti at which the valve closing operation time Toff takes a peak value ToffP, the valve closing operation time Toff and transfer time ΔT required for the transfer from a valve opening state to a closed state by an energization force of a second spring for energizing a valve body in a valve closing direction.

Description

  The present invention relates to a drive control device for a solenoid valve, and more particularly to a device that controls opening and closing of a solenoid valve that controls the flow rate of a fluid, such as a fuel injection valve and an exhaust gas recirculation control valve mounted on an internal combustion engine.

  Patent Document 1 discloses an electromagnetic valve control device that detects an actual opening timing of an electromagnetic valve based on a driving current waveform of the electromagnetic valve and detects an actual closing timing of the electromagnetic valve based on a driving voltage waveform. ing. According to this device, the inflection point of the current waveform is detected as the actual valve opening timing, and the inflection point of the voltage waveform is detected as the actual valve closing timing.

JP-A-6-174139

  When the actual valve opening timing is detected using the method of the above-described conventional apparatus, there are the following problems, and FIG. 10 is a waveform diagram shown for explaining the problem. FIG. 10 shows the drive current waveform ID (solid line) of the fuel injection valve and the secondary differential waveform IDD (broken line) of the drive current waveform, and the timing at which the secondary differential waveform IDD becomes the maximum value or the minimum value is shown. This corresponds to the inflection point of the drive current waveform ID. Note that SDCTL shown in FIG. 10 is a drive control signal, and LFT is a lift amount of the valve body.

  As shown in FIG. 10, in the process of increasing the drive current, an inflection point P2 due to magnetic saturation accompanying the increase in drive current appears at a timing close to the inflection point P1 corresponding to the valve opening timing. In some cases, the inflection point P1 may not be detected accurately. In addition, when the drive current necessary for opening the valve is obtained early and energization is terminated immediately after the valve opening timing, the inflection point P1 may not be accurately detected by the inflection point P3 due to the end of energization. .

  The present invention has been made to solve this problem. An electromagnetic valve that can more accurately determine the actual opening timing of the solenoid valve and improve the control accuracy of the actual opening time of the solenoid valve. An object is to provide a drive control device.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a valve closing timing acquisition means for acquiring a valve closing timing (tCL) of the solenoid valve in a drive control device for the solenoid valve (2) for controlling the flow rate of fluid. And an opening timing estimating means for estimating the opening timing (tOP) of the solenoid valve based on the closing timing (tCL) acquired by the closing timing acquisition means, and the estimation by the opening timing estimation means Control means for outputting a drive signal (SDCTL) for controlling the drive of the electromagnetic valve based on the valve opening timing (tOP), and the valve opening timing estimation means is a time point (tIE) when the drive signal is turned off. ) To the valve closing timing (tCL), the valve closing operation time calculation means for calculating the valve closing operation time (Toff) corresponding to the time from the valve closing timing (tCL). The drive when taking Transition from a valve-open state to a valve-closed state by the force of the spring (40) that urges the valve body of the solenoid valve in the valve-closing direction and the valve closing operation time (Toff) The opening time (tOP) of the electromagnetic valve is estimated based on the transition time (ΔT) required for the operation.

  According to this configuration, the closing timing of the solenoid valve is acquired, the opening timing of the solenoid valve is estimated based on the acquired closing timing, and the driving of the solenoid valve is performed based on the estimated opening timing. A driving signal to be controlled is output. Specifically, the valve closing operation time corresponding to the time from when the drive signal is turned off to the valve closing timing is calculated, the duration of the drive signal when the valve closing operation time takes a peak value, and the valve closing operation The opening timing of the solenoid valve is estimated based on the time and the transition time required for the transition from the opened state to the closed state by the force of the spring that biases the valve body of the solenoid valve in the closing direction. When the valve closing operation time takes a peak value, the transition time is calculated in advance in order to cope with a state where the valve body of the solenoid valve reaches the maximum lift position and there is no rebound (bounce operation) at the maximum lift position. I can keep it. Therefore, by using the duration of the drive signal, the valve closing operation time, and the transition time, the timing at which the valve body reaches the maximum lift position can be calculated as the actual valve opening timing. As a result, an accurate actual opening time of the solenoid valve (acquired valve closing timing−estimated actual valve opening timing) is obtained, and by correcting the drive signal according to the obtained actual valve opening time, The control accuracy of the actual valve opening time can be increased. In the present specification, the time when the valve body reaches the maximum lift position is defined as the actual valve opening time, and the time from the actual valve opening time to the actual valve closing time is defined as the actual valve opening time.

  According to a second aspect of the present invention, in the electromagnetic valve drive control device according to the first aspect, the valve opening timing estimating means determines the duration (Ti) of the drive signal as the valve body (32) of the electromagnetic valve. ) Is gradually increased from a time shorter than the time to reach the maximum lift position, thereby specifying the duration (TiC) when the valve closing operation time (Toff) takes a peak value (ToffP). Features.

  According to this configuration, the continuation time when the valve closing operation time takes the peak value by gradually increasing the duration of the drive signal from a time shorter than the time when the valve body of the solenoid valve reaches the maximum lift position. (Peak valve opening command time) is specified. Compared to the method of gradually shortening the drive signal duration from a state longer than the peak valve opening command time, false detection of the peak valve opening command time is less likely to occur, so the peak valve opening command time can be specified easily and accurately. In addition, it is possible to accurately estimate the actual opening timing.

  According to a third aspect of the present invention, in the electromagnetic valve drive control device according to the first or second aspect, the valve closing operation is performed from a state in which the valve body (32) of the electromagnetic valve is securely held at the maximum lift position. A spring constant estimating means for calculating an estimated value (kHAT) of the spring constant of the spring based on the valve closing operation time (Toff) when the duration (Ti) of the drive signal is set to start; And a correction means for correcting the transition time (ΔT) based on the estimated value (kHAT) of the spring constant.

  According to this configuration, the spring is based on the valve closing operation time when the duration of the drive signal is set so as to start the valve closing operation from the state where the valve body of the solenoid valve is securely held at the maximum lift position. An estimated value of the constant is calculated, and the transition time is corrected based on the estimated value of the spring constant. Since the spring constant of the spring that biases the valve body in the valve closing direction is accompanied by manufacturing variations and changes with time, an estimated value of the spring constant is calculated based on the actually measured valve closing operation time, and based on the estimated value. By correcting the transition time, the estimation accuracy of the actual valve opening timing can be improved and maintained.

  According to a fourth aspect of the present invention, in the electromagnetic valve drive control device according to any one of the first to third aspects, the drive when the valve closing operation time (Toff) takes a peak value (ToffP). An abnormality determining means for determining that there is an abnormality in the electromagnetic valve when the signal duration (TiC) cannot be specified is further provided.

  According to this configuration, when the duration of the drive signal when the valve closing operation time takes the peak value cannot be specified, it is determined that the electromagnetic valve is abnormal. For example, if there is an abnormality such that the electromagnetic force generated by the solenoid is smaller than the design value, the valve body may not reach the maximum lift position, and the duration time during which the valve opening operation time takes the peak value may not be specified. Therefore, in such a case, it is possible to normalize at an early stage by determining that there is an abnormality and responding by turning on the warning lamp.

  According to a fifth aspect of the present invention, in the electromagnetic valve drive control device according to any one of the first to fourth aspects, the electromagnetic valve (2) includes a solenoid (39) to which the drive signal is supplied. A core (35) on which an electromagnetic force generated by the solenoid acts, and a valve shaft (31) to which the valve body (32) is fixed, the core (35) and the valve shaft (31) being It has a hammering core structure configured separately.

  The valve closing operation time has a peak value because the main factor is that the core bounces when the valve body is moved to the maximum lift position. Therefore, the drive control device for the solenoid valve having the hammering core structure Thus, a remarkable effect of increasing the estimation accuracy of the actual valve opening timing can be obtained.

1 is a diagram illustrating an internal combustion engine and a control device thereof according to an embodiment of the present invention. It is sectional drawing for demonstrating the structure of the principal part of the fuel injection valve shown in FIG. It is a time chart for demonstrating the definition of the parameter in this specification. It is a figure which shows the transition (valve opening operation characteristic) of the relationship between valve opening command time (Ti) and valve closing operation time (Toff), and lift amount (LFT). It is a figure for demonstrating the transition time ((DELTA) T) in the state in which valve closing operation time (Toff) takes a peak value (ToffP). It is a flowchart of a fuel injection control process. 7 is a flowchart of a Ton calculation process executed in the process of FIG. 8 is a flowchart of a ΔT calculation process executed in the process of FIG. It is a figure which shows the table referred by the process of FIG. It is a figure for demonstrating the subject of a prior art.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a view showing an internal combustion engine (hereinafter referred to as an “engine”) and a control device thereof according to an embodiment of the present invention. In this embodiment, a fuel injection valve opened by a solenoid valve having a solenoid is opened. The amount of fuel supplied to the engine is controlled by changing the time.

  The four-cylinder engine 1 includes four fuel injection valves 2 corresponding to the cylinders, and the fuel injection valves 2 directly inject fuel into the combustion chamber of the engine 1. Each of the four fuel injection valves 2 is connected to the ECU 5, and its operation is controlled by the ECU 5.

  The fuel injection valve 2 is connected to a delivery pipe 4 through a fuel passage 3, and fuel pressurized by a high-pressure fuel pump (not shown) is supplied to the delivery pipe 4. A fuel pressure sensor 12 for detecting the fuel pressure PF is attached to the delivery pipe 4, and the detection signal is supplied to the ECU 5.

  The ECU 5 includes a voltage / current sensor 11 that detects a voltage VSL across the solenoid of the fuel injection valve 2 and a drive current ID supplied to the solenoid, an engine speed sensor 13 that detects the speed NE of the engine 1, Various sensors for detecting an engine operating state such as an intake air flow rate sensor 14 for detecting an intake air flow rate GAIR, an intake air temperature sensor 15 for detecting an intake air temperature TA, and a cooling water temperature sensor 16 for detecting an engine cooling water temperature TW are connected. The detection signals from these sensors are supplied to the ECU 5. The ECU 5 calculates the required valve opening time TIB of the fuel injection valve 2 according to the engine operating state using the detection signals of these sensors, calculates the valve opening command time Ti according to the required valve opening time TIB, and opens it. Drive control of the fuel injection valve 2 is performed using the valve command time Ti.

  FIG. 2 is a cross-sectional view for explaining a configuration of a main part of the fuel injection valve 2. The fuel injection valve 2 includes a valve shaft 31, a valve body 32 fixed to the tip of the valve shaft 31, and a valve shaft 31. Flanges 33, 34 fixed to the core, a core 35 on which electromagnetic force acts, a first spring 36 provided between the core 35 and the flange 34, a valve seat 37, a sleeve 38, a solenoid 39, A second spring 40 that urges the flange 34 in the valve closing direction (downward in the figure) and an inner collar 41 having a hollow portion that functions as a fuel passage are provided. The fuel injection valve 2 has a so-called hammering core structure in which a core 35 and a valve shaft 31 to which a valve body 32 is fixed are configured separately.

FIG. 3 is a time chart for explaining the definition of parameters in this specification, and shows the transition of the lift amount LFT of the valve element 32 and the valve opening command signal SDCTL.
As indicated by the solid line, the time during which the valve opening command signal SDCTL is output, that is, the time from the valve opening command timing tIS to the valve closing command timing tIE is the valve opening command time Ti, and the lift amount LFT becomes the maximum lift amount. The valve opening timing tOP is reached, the time from the valve opening command timing tIS to the valve opening timing tOP is the valve opening operation time Ton, and the time when the lift amount LFT reaches “0” after the valve closing command timing tIE. It is the valve closing timing tCL, the time from the valve closing command timing tIE to the valve closing timing tCL is the valve closing operation time Toff, and the time from the valve opening timing tOP to the valve closing timing tCL is the actual valve opening time TOP. By defining the actual valve opening time TOP in this way, the relationship between the actual valve opening time TOP and the fuel injection amount can be made closer to a proportional relationship.
The characteristic indicated by the broken line indicates the valve opening operation characteristic when the valve opening command time Ti is changed to Ti1 and Ti2, and the valve closing operation time is indicated by Toff1 and Toff2, respectively.

  In addition, in the range shown by RB in FIG. 3A, the characteristic that the lift amount LFT increases or decreases is caused by the bounce operation unique to the solenoid valve having the hammering core structure. The bounce operation is an operation in which the core 35 is attracted by electromagnetic force and moves upward together with the valve shaft 31 and the valve body 32, and when reaching the lower end of the sleeve 38, the core 35 is bounced and vibrates slightly up and down. is there. When the valve opening command time Ti increases, the valve body 32 is stably held at the maximum lift position.

  4 (a) shows the relationship between the valve opening command time Ti and the valve closing operation time Toff, and FIG. 4 (b) shows the transition of the lift amount LFT (valve opening operating characteristic) as in FIG. 3 (a). . With reference to these figures, the relationship between the valve opening command time Ti and the valve closing operation time Toff will be described. Dashed lines LA, LB, and LC shown in FIG. 4 (b) indicate the transition of the lift amount LFT during the valve closing operation, and the valve opening command time Ti is set to the first time TiA and the second time shown in FIG. 4 (a), respectively. This corresponds to the case where TiB and the third time TiC are set.

  If the valve opening command signal SDCTL is turned off immediately before the core 35 hits the sleeve 38, the core 35 hits the sleeve 38, and a downward force acts on the core 35. Therefore, the valve closing operation time Toff is shortened. That is, when the valve opening command time Ti is gradually shortened from the first time TiA, the valve closing operation time Toff is gradually shortened. When the valve opening command time Ti is the second time TiB, the valve closing operation time Toff is minimized.

  As the valve opening command time Ti is further shortened, the force with which the core 35 abuts against the sleeve 38 becomes weaker, and thus the downward force acting on the core 35 becomes weaker, so that the valve closing operation time Toff becomes gradually longer. When the valve opening command time Ti is the third time TiC (peak valve opening command time), the valve closing operation time Toff is maximized (takes a peak value ToffP). In a range where the valve opening command time Ti is shorter than the third time TiC, the valve closing operation time Toff decreases as the valve opening command time Ti decreases.

The valve closing operation time Toff takes the peak value ToffP because the valve opening command signal SDCTL is turned off before the valve element 32 reaches the maximum lift position, and the core 35 slightly touches the sleeve 38 or immediately before it. This is a case where the movement reaches the position and moves in the valve closing direction. In this case, the lift characteristic of the valve element 32 is a simple spring-mass characteristic, and the position x of the valve element 32 at time t can be expressed by the following equation (1). In Equation (1), m is the total mass of movable parts such as the valve body 32, the valve shaft 31, and the core 35, k is the spring constant of the second spring 40, and A and B are determined experimentally. Is a constant.

  Using Expression (1), the time required for the valve body 32 to move the stroke amount St in the valve closing direction, that is, the time required to shift from the fully open state to the fully closed state (hereinafter referred to as “transition time”) ΔT Can be calculated. The transition time ΔT is a parameter that becomes constant if the stroke amount St (maximum lift amount), the spring constant k, and the mass m are constant, and a value calculated in advance is applied as an initial value, and in particular, the spring constant k. The control accuracy is maintained by performing the correction described later with respect to variations and changes with time.

  As shown in FIG. 5, the transition time ΔT corresponds to the time from the valve opening timing tOP to the valve closing timing tCL in a state where the valve closing operation time Toff takes the peak value ToffP. The valve closing timing tCL is detected using, for example, a conventional technique disclosed in Patent Document 1, and the valve closing operation time Toff is calculated as (tCL-tIE).

Therefore, the valve opening operation time Ton can be calculated by applying the peak valve opening command time TiC, the peak value ToffP of the valve closing operation time, and the transition time ΔT to the following equation (2), and the valve opening timing tOP Can be calculated by adding the valve opening operation time Ton to the valve opening command timing tIS (formula (3)).
Ton = TiC + ToffP−ΔT (2)
tOP = tIS + Ton (3)
If the valve opening command time tIS is set to the reference time “0”, tOP = Ton.

  FIG. 6 is a flowchart of the fuel injection control process in the present embodiment, and this process is executed by the ECU 5. In this process, the valve opening timing tOP is calculated for each fuel injection valve 2 using the above-described method, and fuel injection is performed while correcting the valve opening command time Ti using the valve opening timing tOP.

  In step S11, it is determined whether or not the learning mode flag FLRN is “1”. The learning mode flag FLRN is set to “1” for a predetermined time, for example, during idling after the engine 1 has been warmed up.

  When the learning mode flag FLRN is “1”, the process proceeds from step S11 to step S12, the Ton calculation process shown in FIG. 7 is executed, and the valve opening operation time Ton is calculated by the method described above. In step S13, the valve opening timing tOP is calculated by the above equation (3).

In the normal operation mode in which the learning mode flag FLRN is “0”, the process proceeds from step S11 to step S14, and the required valve opening time TIB is calculated according to the engine operating state (step S14). Applying to (4), the valve opening command time Ti is calculated (step S15). The DTI in equation (4) is the correction time calculated in step S19 described later.
Ti = TIB + DTI (4)

In step S16, fuel injection corresponding to the calculated valve opening command time Ti is executed, and in step S17, the valve closing timing tCL is detected. In step S18, the actual valve opening time TOP is calculated by applying the detected valve closing timing tCL and the valve opening timing tOP calculated in step S13 to the following equation (5).
TOP = tCL-tOP (5)

In step S19, the correction time DTI is calculated by applying the required valve opening time TIB and the actual valve opening time TOP to the following equation (6).
DTI = TIB-TOP (6)

FIG. 7 is a flowchart of the Ton calculation process executed in step S12 of FIG.
In step S31, the ΔT calculation process shown in FIG. 8 is executed to calculate the transition time ΔT. In step S32, the index parameter j is set to “1”, and the valve opening command time T (j) is set to the initial value TiINI (for example, 0.4 msec). The initial value TiINI is set to a time shorter than the peak valve opening command time TiC shown in FIG. 4A, that is, a value smaller than the minimum value of the valve opening command time Ti for the valve body 32 to reach the maximum lift position.

  In step S33, the fuel pressure PF is set to a predetermined pressure PFLRN, fuel injection is performed, and the valve closing operation time Toff (j) is detected. Specifically, the valve closing timing tCL is detected, and the valve closing operation time Toff (j) is obtained as the time from the valve closing timing tCL to the valve closing command timing tIE. In step S35, it is determined whether or not the valve closing operation time Toff (j) is longer than the previous value Toff (j-1). Toff (0) is set to “0”, the answer to step S35 is negative (NO) at first, and the process proceeds to step S36.

  In step S36, the index parameter j is increased by “1”, and the valve opening command time Ti (j) is increased by a predetermined increment value DT (for example, 0.005 msec). In step S37, it is determined whether or not the index parameter j is equal to an upper limit value jHL (for example, 30). Initially, this answer is negative (NO), and the process returns to step S33. Therefore, in steps S33 to S37, the valve closing operation time Toff (j) is detected while gradually increasing the valve opening command time Ti (j) by the predetermined increment value DT.

If the answer to step S35 is negative (NO), that is, if the valve closing operation time Toff (j) is equal to or less than the previous value, the process proceeds to step S38, and the valve opening operation time Ton is calculated by the following equation (2a). That is, when the change in the valve closing operation time Toff (j) changes from increase to decrease, the valve opening operation time Ton is calculated by regarding the immediately preceding value as the peak value ToffP.
Ton = Ti (j−1) + Toff (j−1) −ΔT (2a)

  If the answer to step S35 is not negative (NO) and the index parameter j reaches the upper limit value jHL, the answer to step S37 is affirmative (YES), and the abnormality detection flag FERROR is set to “1” (step S39). ). If the fuel injection valve 2 is normal, the upper limit value jHL is set so that the answer to step S35 is negative (NO) before the index parameter j reaches the upper limit value jHL, and the answer to step S37 is affirmative. When (YES), it is determined that there is an abnormality in the fuel injection valve 2. When the abnormality detection flag FERROR is set to “1”, for example, a warning lamp is turned on to notify the driver of the occurrence of abnormality.

FIG. 8 is a flowchart of the ΔT calculation process executed in step S31 of FIG.
In step S41, the valve opening command time Ti is set to a predetermined learning time TiLRN (for example, 2 msec). The predetermined learning time TiLRN is larger than the range of the valve opening command time in which the bounce operation of the core 35 shown in FIG. 3A occurs, that is, the valve closing operation is performed from the state in which the valve body 32 is securely held at the maximum lift position. Is set to such a value that will start.

  In step S42, the fuel pressure PF is set to a predetermined pressure PFLRN, fuel injection is performed, and the valve closing operation time Toff is detected (step S43). The k table in which the relationship between the spring constant k and the valve closing operation time Toff shown in FIG. 9A is set according to the obtained valve closing operation time Toff is searched, and the spring constant estimated value kHAT is calculated (step) S44). The k table is set so that the spring constant k decreases as the valve closing operation time Toff increases.

In step S45, the DTC table shown in FIG. 9B is searched according to the spring constant estimated value kHAT, and the correction value DTC is calculated. The DTC table is preset using the spring constant estimated value kHAT and the equation (1), and is set so that the correction value DTC increases as the spring constant estimated value kHAT decreases. In FIG. 9B, k0 is the design median value of the spring constant k.
In step S46, the transition time ΔT is updated by adding the correction value DTC to the current transition time ΔT.

  As described above, in this embodiment, the closing timing tCL of the fuel injection valve 2 is detected, the opening timing tOP is estimated based on the detected closing timing tCL, and based on the estimated opening timing tOP. Then, the valve opening command signal SDCTL for the fuel injection valve 2 is output. Specifically, when the valve opening command signal SDCTL is turned off, that is, the valve closing operation time Toff corresponding to the time from the valve closing command timing tIE to the valve closing timing tCL is calculated, and the valve closing operation time Toff is the peak value ToffP. The valve opening command time TiC, the peak value ToffP, and the transition time required to shift from the valve opening state to the valve closing state by the urging force of the second spring 40 that urges the valve body 32 in the valve closing direction. Based on ΔT, the opening timing tOP of the fuel injection valve 2 is estimated. When the valve closing operation time Toff takes the peak value ToffP, the transition time ΔT is calculated in advance in order to correspond to the state in which the valve body 32 reaches the maximum lift position and there is no rebound (bounce operation) at the maximum lift position. I can keep it. Therefore, the timing at which the valve body 32 reaches the maximum lift position can be calculated as the valve opening timing tOP by using the peak valve opening command time TiC, the peak value ToffP of the valve closing operation time, and the transition time ΔT. As a result, an accurate actual valve opening time TOP (valve closing timing tCL−valve opening timing tOP) of the fuel injection valve 2 is obtained, and the required valve opening time TIB is corrected according to the obtained actual valve opening time TOP. Thus, the control accuracy of the actual valve opening time TOP, that is, the control accuracy of the fuel injection amount can be increased.

  Further, the valve opening command time Ti is gradually increased from a time shorter than the time when the valve body 32 reaches the maximum lift position (FIG. 4, TiC), so that the valve opening operation time Toff is opened when the peak value ToffP is taken. The peak valve opening command time TiC, which is the valve command time, is specified. Compared to the method in which the valve opening command time Ti is gradually shorter than the peak valve opening command time TiC, the peak valve opening command time TiC is less likely to be detected. It is possible to accurately identify and accurately estimate the actual valve opening timing tOP.

  Further, the spring constant is based on the valve closing operation time Toff when the valve opening command time Ti is set to the predetermined learning time TiLRN so that the valve closing operation is started from the state where the valve body 32 is securely held at the maximum lift position. The estimated value kHAT is calculated, and the transition time ΔT is corrected based on the spring constant estimated value kHAT. Since the spring constant k of the second spring 40 that biases the valve body 32 in the valve closing direction is accompanied by manufacturing variations and changes with time, the estimated value kHAT of the spring constant is calculated based on the actually measured valve closing operation time Toff. By calculating and correcting the transition time ΔT based on the estimated value kHAT, it is possible to improve and maintain the estimation accuracy of the actual valve opening timing tOP.

  Further, when the valve opening command time TiC when the valve closing operation time Toff takes the peak value ToffP cannot be specified, it is determined that the fuel injection valve 2 is abnormal. For example, if there is an abnormality such that the electromagnetic force generated by the solenoid 39 is smaller than the design value, the peak valve opening command time TiC at which the valve closing operation time Toff takes the peak value ToffP without the valve body 32 reaching the maximum lift position is set. There is a possibility that it cannot be identified. Therefore, in such a case, it is possible to normalize at an early stage by determining that there is an abnormality and responding by turning on the warning lamp.

  Further, the reason why the valve closing operation time Toff takes the peak value ToffP is that the core 35 bounces when the valve body 32 is moved to the maximum lift position, and therefore the fuel having the hammering core structure. In the injection valve drive control device, a remarkable effect of increasing the estimation accuracy of the actual valve opening timing tOP can be obtained.

  In the present embodiment, the voltage / current sensor 11 constitutes part of the valve closing timing acquisition means, and the ECU 5 includes part of the valve closing timing acquisition means, valve closing operation time calculation means, valve opening timing estimation means, control means, A spring constant estimation unit, a correction unit, and an abnormality determination unit are configured. Specifically, step S34 in FIG. 7 corresponds to valve closing timing acquisition means and valve closing operation time calculation means, steps S34 to S38 correspond to valve opening timing estimation means, and steps S37 and S39 serve as abnormality determination means. 8 corresponds to the spring constant estimation means, and steps S45 and S46 correspond to the correction means.

  The present invention is not limited to the embodiment described above, and various modifications can be made. For example, in the above-described embodiment, when specifying the peak valve opening command time TiC, the valve opening command time Ti is gradually increased from a value smaller than the peak valve opening command time TiC. You may make it reduce gradually from the larger value than instruction | command time TiC.

  In the above-described embodiment, an example in which the present invention is applied to a drive control device for a fuel injection valve of an internal combustion engine has been described. However, a general electromagnetic valve for controlling the flow rate of fluid, for example, an exhaust gas recirculation amount is controlled. The present invention can also be applied to a drive control device such as a solenoid valve or a solenoid valve that controls the flow rate of hydraulic oil in an automatic transmission.

1 Internal combustion engine 2 Fuel injection valve (solenoid valve)
5 Electronic control unit (valve closing timing acquisition means, valve closing operation time calculation means, valve opening timing estimation means, control means, spring constant estimation means, correction means, abnormality determination means)
11 Voltage current sensor (valve closing time acquisition means)

Claims (5)

In a drive control device for a solenoid valve that controls the flow rate of fluid,
Valve closing timing acquisition means for acquiring the valve closing timing of the solenoid valve;
Based on the valve closing timing acquired by the valve closing timing acquiring means, the valve opening timing estimating means for estimating the valve opening timing of the solenoid valve;
Control means for outputting a drive signal for controlling the drive of the electromagnetic valve based on the valve opening time estimated by the valve opening time estimating means;
The valve opening timing estimating means includes valve closing operation time calculating means for calculating a valve closing operation time corresponding to a time from when the drive signal is turned off to the valve closing timing, and the valve closing operation time is peaked. Required for transition from the open state to the closed state by the duration of the drive signal when taking the value, the valve closing operation time, and the force of the spring that biases the valve body of the electromagnetic valve in the valve closing direction An electromagnetic valve drive control device that estimates the valve opening timing of the electromagnetic valve based on a transition time.   The valve opening timing estimation means is configured to gradually increase the duration of the drive signal from a time shorter than a time when the valve body of the solenoid valve reaches the maximum lift position, thereby causing the valve closing operation time to reach a peak value. The drive control device for an electromagnetic valve according to claim 1, wherein the duration time when taking a value is specified. The spring of the spring based on the valve closing operation time when the duration of the drive signal is set so as to start the valve closing operation from the state where the valve body of the electromagnetic valve is securely held at the maximum lift position. Spring constant estimating means for calculating an estimated value of the constant;
The electromagnetic valve drive control device according to claim 1, further comprising a correction unit that corrects the transition time based on the estimated value of the spring constant.   4. The apparatus according to claim 1, further comprising an abnormality determination unit that determines that the electromagnetic valve is abnormal when the duration of the drive signal when the valve closing operation time takes a peak value cannot be specified. The drive control apparatus of the solenoid valve any one of these.   The solenoid valve includes a solenoid to which the drive signal is supplied, a core to which an electromagnetic force generated by the solenoid acts, and a valve shaft to which the valve body is fixed. The core and the valve shaft are separated from each other. 5. The drive control device for an electromagnetic valve according to claim 1, further comprising a hammering core structure configured on the body.

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