JP4177745B2 - Control device for electromagnetically driven valve - Google Patents

Description

  The present invention relates to an electromagnetically driven valve control device, and more particularly, to an electromagnetically driven valve control device that controls an electromagnetically driven valve that opens and closes an intake valve and an exhaust valve disposed in each cylinder of an internal combustion engine with an electromagnetic coil.

  Instead of opening and closing the intake and exhaust valves of an internal combustion engine using a mechanical valve mechanism, the opening and closing timing is controlled electrically by using electromagnetic force generated by energization of an electromagnetic coil. It is known to improve performance.

  For example, in Patent Document 1 below, each cylinder is provided with an electromagnetically driven valve as an intake valve and an exhaust valve that is opened and closed by an opening and closing electromagnetic coil, and an internal combustion engine includes a control unit constituted by a microcomputer and each It has been proposed to provide an electromagnetically driven valve control device comprising a drive unit for energizing and driving the electromagnetic coil for opening and closing the electromagnetically driven valve, and controlling the electromagnetically driven valve by this system.

  In such an electromagnetically driven valve control device, the control unit has a target current value for two (open and closed) electromagnetic coils provided in each electromagnetically driven valve based on the operating state of the engine and the lift amount of the electromagnetically driven valve. Are converted to analog signals and output to the drive unit. The drive unit energizes the drive current to the electromagnetic coil of each electromagnetic drive valve according to the input target current value. In this system, a plurality of control signals are output from the control unit to the drive unit in order to reduce the number of D / A converters of the control unit used to output the target current value.

  On the other hand, in relation to control of an electromagnetically driven valve of an internal combustion engine, for example, in Patent Document 2 below, a control unit (command signal generating means) is provided with an intake air in order to reduce the communication processing load from the control unit to the drive unit. Command signals including identification data (ID) of electromagnetic coils provided in electromagnetically driven valves as valves and exhaust valves, electromagnetic actuators of automatic transmissions, etc., and command current values for the respective electromagnetic coils at predetermined time intervals It has been proposed to select a command signal that is generated and has a large change in the command current value, and to sequentially transmit only the selected command signal to the corresponding electromagnetic coil.

JP 2002-43127 A (pages 1 to 15, FIGS. 1 to 13) JP 2003-17317 A (pages 1 to 16, FIGS. 1 to 19)

  By the way, in the electromagnetically driven valve control apparatus, since the operating environment conditions of the control unit having a microcomputer and the drive unit to which a large amount of power is supplied are different, it can be considered that they are installed in different places. However, in the electromagnetically driven valve control device as described above, since the control unit and the drive unit are connected by a plurality of analog signals and a plurality of control signals, wiring between both units becomes complicated.

  In order to solve this problem, a system is conceivable in which the control unit and the drive unit are connected via a serial transmission path, and the target current values for all the electromagnetically driven valves (the electromagnetic coils) are transferred by serial communication. However, the engine is provided with a large number of electromagnetically driven valves, and the number of target current values transferred from the control unit to the drive unit is large. For example, when the engine is composed of four cylinders and each cylinder has two intake valves and two exhaust valves, the number of electromagnetically driven valves is 16, the number of electromagnetic coils is 32, that is, the number of target current values. Becomes 32. Therefore, it takes a long time to transfer the target current values for all the electromagnetic coils from the control unit to the drive unit. After the energization amount (target current value) is set in the control unit, it is actually used to energize the electromagnetic coils. It takes longer to reflect. Further, the cycle for transferring the target current value cannot be shorter than the transfer time. Therefore, there is a problem that the control cycle becomes long and it is difficult to improve responsiveness and control accuracy.

  The technique described in Patent Document 2 can reduce the communication processing load from the control unit to the drive unit. However, as described above, two electromagnetic coils for opening and closing are provided in one electromagnetically driven valve. If provided, it is not effective to reduce the number of target current values (command current values) to be transmitted to shorten the transfer time.

  The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to shorten the transfer time of the target current value by serial communication, thereby shortening the control cycle and the response of the electromagnetically driven valve. It is another object of the present invention to provide a control device for an electromagnetically driven valve that can improve control accuracy and the like.

  In order to achieve the above object, an electromagnetically driven valve control device according to the present invention controls an electromagnetically driven valve that controls an electromagnetically driven valve that opens and closes an intake valve and an exhaust valve disposed in each cylinder of an internal combustion engine by an electromagnetic coil. The apparatus includes control means for setting a target current value to be supplied to each electromagnetic coil, and drive means for energizing and driving the electromagnetic coil based on the target current value set by the control means.

  The control means includes a target current value for the electromagnetic coil to be energized, and an identifier for identifying whether the target current value corresponds to the opening or closing electromagnetic coil in the electromagnetically driven valve, Transmitting to the drive means in a predetermined order by serial communication, the drive means is configured to select an electromagnetic coil to be energized based on the received identifier.

  In a preferred aspect, the driving means drives the electromagnetic coil corresponding to the received identifier to be energized based on the newly received target current value, and stops energization to the electromagnetic coil not corresponding to the received identifier. .

  In another preferable aspect, the driving means energizes and drives the electromagnetic coil corresponding to the received identifier based on the newly received target current value, and sets the electromagnetic coil not corresponding to the received identifier to the previously received target current value. Based on this, energization driving is performed.

  In a preferable aspect of the electromagnetically driven valve control device according to the present invention configured as described above, the target current value transferred from the control means to the drive means corresponds to any of the open and close electromagnetic coils. Since an identifier (ID) for identifying the current value is added, only the target current value of the electromagnetic coil to be energized is transferred, and the target current value of the electromagnetic coil that does not need to be energized need not be transferred.

  Therefore, the number of target current values to be transferred from the control means to the driving means can be halved, and the data transfer amount per time can be reduced. As a result, the total transfer time of the target current values from the control means to the driving means can be reduced. Can be shortened to nearly half.

  As a result, the control cycle can be shortened, and as a result, the responsiveness and control accuracy of the electromagnetically driven valve can be improved.

  On the other hand, another electromagnetically driven valve control device according to the present invention is an electromagnetically driven valve control device that controls an electromagnetically driven valve that opens and closes an intake valve and an exhaust valve disposed in each cylinder of an internal combustion engine by an electromagnetic coil. Control means for setting a target current value to be supplied to each electromagnetic coil, and drive means for energizing and driving the electromagnetic coil based on the target current value set by the control means.

  The control means identifies the target current value of the electromagnetic coil for opening and closing to be energized and the electromagnetic valve to be opened / closed of the electromagnetically driven valve whose target current value is to be changed. And a second identifier for identifying whether the target current value corresponds to an opening or closing electromagnetic coil in the electromagnetically driven valve is predetermined by serial communication. The driving means transmits the electromagnetic coil of the electromagnetically driven valve that does not correspond to the received first identifier based on the previously received target current value, and the received first identifier is transmitted to the driving means in order. Among the corresponding electromagnetic coils of the electromagnetically driven valve, the electromagnetic coil corresponding to the received second identifier is energized and driven based on the newly received target current value, and the electromagnetic coil does not correspond to the received second identifier It is characterized by being adapted to stop the energization.

  As a result, only the target current value for the electromagnetic coil to be energized provided in the electromagnetically driven valve to be opened and closed (during the valve opening period) needs to be transferred. Since it is not necessary to transfer the target current value of the electromagnetic coil having no target, the transfer time of the target current value can be shortened.

  In another preferred aspect, the control means has a target current value for an intake valve of a plurality of cylinder groups consisting of a plurality of cylinders that do not overlap with each other, and an opening period of the exhaust valve. A target current value for an exhaust valve of a plurality of cylinder groups including a plurality of cylinders that do not overlap is set, and the target current value includes a plurality of target current values that partially overlap the valve opening periods of the electromagnetically driven valves. A first identifier for identifying which of a plurality of cylinder groups consisting of cylinders corresponds is added.

  In another electromagnetically driven valve control device according to the present invention configured as described above, the first identifier and the second identifier are added to the target current value to energize the electromagnetically driven valve to be opened and closed. Since only the target current value for the power electromagnetic coil is transferred and it is not necessary to transfer the target current value of the electromagnetic coil that does not need to be energized, the number of target current values to be transmitted from the control means to the drive means can be greatly reduced. (For example, if each cylinder has one intake valve and one exhaust valve in the inline four cylinders, the number of target current values to be transmitted at one time can be reduced to 1/4). Data transfer volume can be greatly reduced. As a result, the transfer time of the target current value from the control unit to the drive unit can be shortened, which makes it possible to shorten the control cycle, resulting in improved responsiveness, improved control accuracy, etc. Can be planned.

  As can be understood from the above description, the electromagnetically driven valve control device according to the present invention can transmit either of the opening and closing electromagnetic coils of each electromagnetically driven valve when transmitting the target current value from the control means to the driving means. Since only the target current value for one of the coils to be energized needs to be transferred, the transfer time of the target current value can be shortened, thereby making it possible to shorten the control cycle, resulting in improved responsiveness, The control accuracy can be improved. In addition, the transfer time of the target current value is further increased by transferring only the target current value for the valve whose target current value is changed among the intake / exhaust valves whose valve opening periods do not overlap. Thus, the control accuracy of the electromagnetically driven valve can be further improved.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an embodiment of a control device for an electromagnetically driven valve according to the present invention, together with a main part of an example of an internal combustion engine in which the control device is adopted.

  The internal combustion engine 1 includes four cylinders # 1, # 2, # 3, and # 4. Each cylinder # 1, # 2, # 3, # 4 is provided with a piston 3, an intake port 5, an intake valve 4a, an exhaust port 6, an exhaust valve 4b, a spark plug 7, and the like. The intake valve 4a and the exhaust valve 4b are electromagnetically driven valves that are driven to open and close by the closing and opening electromagnetic coils (the upper coil 43a and the lower coil 44a in FIG. 2), respectively. Hereinafter, unless otherwise distinguished, the intake valve 4a and the exhaust valve 4b are referred to as electromagnetically driven valves.

  In this embodiment, each of the cylinders # 1, # 2, # 3, and # 4 is provided with one intake valve 4a and one exhaust valve 4b. However, two intake valves 4a and / or two exhaust valves 4b are provided. You may make it the structure provided above.

  The electromagnetically driven valves 4a and 4b are controlled by an electromagnetically driven valve control device 2 including a control unit 8 and a drive unit 9, respectively.

  The control unit 8 operates at a control cycle shorter than the engine rotation cycle, and lift amount signals 47a and 47b obtained from lift sensors 46a and 46b respectively provided in the electromagnetically driven valves 4a and 4b for each control cycle. The energization amount to be passed through the electromagnetic coils 43a and 43b of the electromagnetically driven valves 4a and 4b is set based on the above, and the set target current value is transmitted to the drive unit 9 via the serial transmission path 806.

  When the control unit 8 sets the energization amount to flow through the electromagnetic coils 43a and 43b of the electromagnetically driven valves 4a and 4b, the operation information of the engine 1 received from various sensors (not shown) or another control unit, for example, The target current value is set with reference to the crank angle and the like.

  The drive unit 9 adjusts the energization amount of the drive current signals 904a, 905a, 904b, 905b to the electromagnetically driven valves 4a, 4b according to the target current value received from the control unit 8.

  FIG. 2 shows a schematic configuration of an electromagnetically driven valve 4a that is an intake valve. The electromagnetically driven valve 4b that is an exhaust valve has the same configuration.

  The electromagnetically driven valve 4a (4b) is fixed to the upper coil 43a and the lower coil 44a serving as electromagnetic coils for generating electromagnetic force, the valve body 40a, the shaft 41a and the shaft 41a, and is attracted by the electromagnetic force of the upper coil 43a and the lower coil 44a. And a pair of upper and lower springs 45a and 45a that are fixed at both ends and urge the armature 42a in the vertical direction. A lift of the valve body 40a is provided near the upper end of the armature 42a. A lift sensor 46a for detecting the amount is attached.

  The upper coil 43a generates an electromagnetic force by the drive current signal 904a sent from the drive unit 9, and attracts the armature 42a upward. Thereby, the valve closing operation is performed. The lower coil 44a generates an electromagnetic force by the drive current signal 905a sent from the drive unit 9, and attracts the armature 42a downward. Thereby, a valve opening operation is performed. Since the electromagnetic force of the upper coil 43a and the lower coil 44a is determined by the energization amount of the drive current signals 904a and 905a, the opening / closing speed of the valve body 40a is adjusted by changing the energization amount.

  When no current is supplied to the upper coil 43a and the lower coil 44a, that is, when no electromagnetic force is generated, the armature 42a is positioned between the upper coil 43a and the lower coil 44a by the spring 45a. In this case, the valve body 40a is located exactly in the middle between the closed state (fully closed) and the open state (fully open). When the armature 42a is attracted upward by the upper coil 43a, the valve body 40a is closed. In this state, force is applied in the opening direction by the spring 45a, so that the valve body 40a is maintained in the closed state. It is necessary to pass a very small current through the upper coil 43a. However, when the valve body 40a is shifted from the closed state to the open state, a force in the opening direction is applied by the spring 45a, so that the energization amount of the lower coil 44a sucked downward can be suppressed. The same applies when the valve body 40a is open.

  The lift sensor 46 a detects the lift amount (opening amount) of the valve body 40 a and outputs a lift amount signal 47 a that is an analog signal corresponding to the lift amount to the control unit 2.

FIG. 3 is a block diagram showing the configuration of the control unit 8.
The control unit 8 includes a CPU (Central Processing Unit) 800, a memory 801, an A / D converter 802, a serial communication module (SCM) 803, and a timer 804 that are connected to each other via a system bus 805.

  The timer 804 notifies the CPU 800 of the starting point of the control cycle for each predetermined control cycle.

  When receiving the notification from the timer 804, the CPU 800 requests the A / D converter 802 to input lift amount signals 47a and 47b (A / D conversion processing). The A / D converter 802 takes in the lift amount signals 47a and 47b, converts them into digital values, and writes them into the memory 801.

  The CPU 800 performs calculation by referring to the operation value of the engine 1 obtained from various sensors (not shown) and other control units in addition to the digital value of the lift amount stored in the memory 801, and the electromagnetically driven valves 4a, 4b. The amount of current applied to each of the coils 43a and 44a is set and written as a target current value in the memory 801, and the serial communication module (SCM) 803 is requested to transmit the target current value (serial transfer).

  The serial communication module (SCM) 803 transmits the target current value on the memory 801 to the drive unit 9 via the serial transmission path 806.

FIG. 4 is a block diagram showing the configuration of the drive unit 9.
The drive unit 9 includes a serial port 900, a current value determination unit (circuit) 901, and drive circuits 902a, 903a, 902b, and 903b. Four drive circuits 902a (for the intake valve upper side), 903a (for the exhaust valve upper side), 902b (for the intake valve lower side), and 903b (for the exhaust valve lower side) are equivalent to one cylinder (the intake valve 4a). Corresponding to the upper coil 43a and the lower coil 44a) of the exhaust valve 4b, and drive circuits corresponding to the other cylinders are similarly provided, but are omitted here.

  The serial port 900 is for receiving a target current value sent from the control unit 8 via the serial transmission path 806. The serial port 900 transmits the received target current value to the current value determination unit 901.

  Based on the target current value from the serial port 900, the current value determination unit 901 determines target values of the drive current signals 904a, 905a, 904b, and 905b to be applied to the coils 43a and 44a of the electromagnetically driven valves 4a and 4b. Signals corresponding to respective target current values are transferred to the drive circuits 902a, 903a, 902b, and 903b.

  The drive circuits 902a, 903a, 902b, and 903b are respectively connected to the drive current signal 904a so that the currents flowing through the coils 43a and 44a of the electromagnetic drive valves 4a and 4b coincide with the target current value received from the current value determination unit 901. , 905a, 904b and 905b are adjusted. As a result, the opening / closing operation speed of the electromagnetically driven valves 4a and 4b is changed and control for maintaining the open state or the closed state is performed.

  In the electromagnetically driven valve control device 2 including the control unit 8 and the drive unit 9 of the present embodiment, the above control is applied to the electromagnetically driven valves 4a and 4b of the cylinders # 1, # 2, # 3, and # 4. Do the same for the same.

  FIG. 5 is a time chart showing opening and closing operations of the intake valves 4a (IN) and the exhaust valves 4b (EX) of the cylinders # 1, # 2, # 3, and # 4 (the horizontal axis is the crank angle [° CA]. ).

  If the ignition sequence of the air-fuel mixture in each cylinder # 1, # 2, # 3, # 4 is # 1, # 3, # 4, # 2, the valve opening period of the intake valve or exhaust valve is shifted by about 180 ° CA, respectively. However, it is repeated in the order of # 1-EX, # 1-IN, # 3-EX, # 3-IN, # 4-EX, # 4-IN, # 2-EX, # 2-IN. Therefore, the valve opening periods of # 1-IN and # 3-EX, # 3-IN and # 4-EX, # 4-IN and # 2-EX, # 2-IN and # 1-EX overlap. .

  Further, although the valve opening period varies depending on operating conditions, it is a period slightly exceeding 180 ° CA. Therefore, the valve opening periods of the valves whose deviation in valve opening period is 180 ° CA overlap each other.

  On the other hand, the valve opening periods of the valves whose deviation in the valve opening period is 360 ° CA do not overlap. That is, the valve opening periods of # 1-IN and # 4-IN, # 2-IN and # 3-IN, # 1-EX and # 4-EX, # 2-EX and # 3-EX do not overlap. .

  FIG. 6 is a time chart showing the relationship between the lift amount of the intake valve 4a, the target current value (IcomUP) of the upper coil 43a of the valve 4a, and the target current value (IcomLW) of the lower coil 44a. The same applies to the exhaust valve 4b and intake valves and exhaust valves of other cylinders.

  The lift amount is shown with the upper side closed and the lower side opened, and the target current values IcomUP and IcomLW are shown with the upper side being positive and the lower side being negative with reference to “0”.

  When the intake valve 4a is maintained in the closed state, the target current value (IcomUP) of the upper coil 43a is a constant current value (hereinafter, referred to as “a suction force that exceeds the downward biasing force of the spring 45a”). Holding current value), the current of the current value is supplied to the upper coil 43a, the target current value (IcomLW) of the lower coil 44a is set to "0", and the current supply to the lower coil 44a is stopped.

  When the intake valve 4a is maintained in the open state, the target current value (IcomLW) of the lower coil 44a is set to a holding current value at which the lower coil 44a generates an attractive force that exceeds the upward biasing force of the spring 45a. The current of the current value is supplied to 44a, the target current value (IcomUP) of the upper coil 43a is set to “0”, and the current supply of the upper coil 43a is stopped.

  When the intake valve 4a is changed from the closed state to the open state, the target current value (IcomUP) of the upper coil 43a is set to “0”, the current supply to the upper coil 43a is stopped, and the electromagnetic force of the upper coil 43a is stopped. Disappears and the intake valve 4a moves downward by the biasing force of the spring 45a. Further, the target current value (IcomLW) of the lower coil 44a is set to an appropriate value corresponding to the lift amount of the intake valve 4a, and the current of the current value is supplied to the lower coil 44a to generate an appropriate electromagnetic force, and the armature 42a. Is sucked into the lower coil 44a. As a result, the intake valve 4a moves downward in a continuous or stepwise manner and is in an open state.

  On the other hand, when the intake valve 4a is changed from the open state to the closed state, the target current value (IcomLW) of the lower coil 44a is set to “0”, the current supply of the lower coil 44a is stopped, and the electromagnetic force of the lower coil 44a is reduced. It disappears, and the intake valve 8 moves upward by the urging force of the spring 45a. Further, the target current value (IcomUP) of the upper coil 43a is set to an appropriate value corresponding to the lift amount of the intake valve 4a, and the current of that value is supplied to the upper coil 43a to generate an electromagnetic force. It is attracted by the upper coil 43a. As a result, the intake valve 8 moves upward in a continuous or stepwise manner and closes.

  Here, as can be understood with reference to FIG. 6, in the internal combustion engine 1, the upper coil 43 a and the lower coil 44 a of the intake coil 4 a (the exhaust valve 4 b) are in the open state and the closed state. It is not necessary to supply current to both at the same time, it is sufficient to supply current to only one and stop supplying current to the other. Further, while the intake valve 4a (exhaust valve 4b) is maintained in the closed state or the open state, a constant holding current is applied to only one of the upper coil 43a and the lower coil 44a and the current supply to the other is stopped. do it. Considering this point, in the electromagnetically driven valve control device 2 of the present embodiment, the uppers provided in the electromagnetically driven valves 4a and 4b in the cylinders # 1, # 2, # 3, and # 4 in the following manner. Energization control of the coil 43a and the lower coil 44a is performed.

  FIG. 7 shows an example of a transfer frame format (format) for transmitting the target current value from the control unit 8 to the drive unit 9.

  The transfer frame format of FIG. 7 includes 16 electromagnetic coils (upper) provided to open and close the intake valves 4a (IN) and the exhaust valves 4b (EX) of the cylinders # 1, # 2, # 3, and # 4. Target current values (to be described later) for half of the eight coils 43a and eight lower coils 44a (four upper coils 43a and four lower coils 44a), and these eight target current values And an error detection code (CRC) for detecting a data error that may occur when the data is transmitted through the serial transmission line 806, and further, each target current value includes the target current value corresponding to the upper coil 43a and the upper coil 43a. An identifier (ID) for identifying which one of the lower coils 44a corresponds is added. This ID can be represented by 1 or more bits. For example, if ID is 1 bit, if ID is 0, it is a target current value for upper coil 43a, and if ID is 1, it is a target current value for lower coil 44a.

  The target current value (including ID) is determined in a predetermined order (for example, # 1-IN → # 4-IN → # 2-IN → # 3-IN → # 1-EX → # 4-EX → # 2- (EX → # 3-EX). As a result, the current value determination unit 901 of the drive unit 9 corresponds to which cylinder # 1, # 2, # 3, and # 4 each target current value corresponds to, and to which of the intake valve 4a and the exhaust valve 4b. Can be determined.

  Here, it is not necessary to supply currents to both the upper coil 43a and the lower coil 44a provided in one electromagnetically driven valve at the same time, as described above. This is because the current supply to the other is stopped and the coil to which the current is to be supplied (the upper coil 43a or the lower coil 44a) is identified by the ID.

  In the control unit 8, the CPU 800 writes the target current values in the memory 801 in the predetermined order, and also writes the ID of each target current value. The error detection code (CRC) is generated and transmitted when the serial communication module (SCM) 803 transmits the target current value.

  FIG. 8 is a flowchart showing a processing example executed by the current value determination unit 901 of the drive unit 9 that operates based on the transfer frame format shown in FIG.

  When the current value determination unit 901 receives the target current value, the current value determination unit 901 executes this process for each of the intake valves 4a and the exhaust valves 4b of the cylinders # 1, # 2, # 3, and # 4, and performs upper processing for each valve. The target current values of the coil 43a and the lower coil 44a are determined.

  First, the current value determination unit 901 determines the target current value corresponding to either the upper coil 43a or the lower coil 44a from the ID added to the target current value (step 801). If ID = 0, that is, if the target current value corresponds to the upper coil 43a, the target current value (IcomUP) of the upper coil 43a is changed to the newly received target current value, and the intake valve 4a or the upper coil 43a of the exhaust valve 4b is energized and driven according to the target current value, while the target current value (IcomLW) of the lower coil 44a is set to "0", and current is supplied to the lower coil 44a of the intake valve 4a or the exhaust valve 4b. Is stopped (step 802).

  On the other hand, in the case of ID = 1, that is, if the target current value corresponds to the lower coil 44a, the target current value (IcomUP) of the upper coil 43a is set to “0” and the upper of the intake valve 4a or the exhaust valve 4b. While the current supply to the coil 43a is stopped, the target current value (IcomLW) of the lower coil 44a is changed to the newly received target current value, and the lower coil 44a of the intake valve 4a or the exhaust valve 4b is energized according to the target current value. (Step 803).

  In the electromagnetically driven valve control device 2 of the present embodiment configured as described above, the target current value transferred to the drive unit 9 from the control unit 8 corresponds to the target current value corresponding to either the upper coil 43a or the lower coil 44a. Therefore, the number of target current values to be transferred from the control unit 8 to the drive unit 9 can be halved, and the transfer amount per transfer can be reduced. Therefore, the transfer time of the target current value from the control unit 8 to the drive unit 9 can be shortened, and thereby the control cycle can be shortened. As a result, the response is improved and the control accuracy is improved. Etc. can be achieved.

  FIG. 9 shows another example of a transfer frame format for transmitting the target current value from the control unit 8 to the drive unit 9.

  The transfer frame format of FIG. 9 is a target current value for the intake valve 4a of two cylinder groups (described later) consisting of any two cylinders of the four cylinders # 1, # 2, # 3, and # 4, and A total of four target current values of target current values for exhaust valves 4b of two cylinder groups (described later) consisting of any two cylinders of four cylinders # 1, # 2, # 3, and # 4, and this It is formed with an error detection code (CRC) for detecting a data error that may occur when four target current values are transmitted through the serial transmission line 806, and each target current value should be opened and closed. In order to identify the first identifier (ID1) for identifying the valve (during the valve opening period) and whether the target current value corresponds to the upper coil 43a or the lower coil 44a in the electromagnetically driven valves 4a, 4b Second identifier (ID2) It has been added.

  ID1 can be indicated by 1 bit or more. For example, if ID is 1 bit and ID1 is 0, a cylinder group consisting of cylinders # 1 &# 2 whose valve opening periods partially overlap (opening start and opening end) overlap. If it is 1, the target current value of the cylinder group consisting of cylinders # 4 &# 3 with partially overlapping valve opening periods is set.

  ID2 can be represented by 1 bit or more. For example, if ID is 1 bit and this bit is 0, the target current value for the upper coil 43a is set, and if it is 1, the target current value for the lower coil 44a is set.

  Here, the target current value is for the intake valve 4a of the cylinder group consisting of cylinders # 1 &# 4 whose valve opening periods do not overlap with each other, and for the intake valve of the cylinder group consisting of cylinders # 2 &# 3 whose valve opening periods do not overlap. 4a, for the exhaust valve 4b of the cylinder group consisting of cylinders # 1 &# 4 whose valve opening periods do not overlap, and for the exhaust valve 4b of the cylinder group consisting of cylinders # 2 &# 3 whose valve opening periods do not overlap. These are transmitted in a predetermined order. As a result, the current value determination unit 901 of the drive unit 9 determines which cylinder group (# 1 &# 4, # 2 &# 3) each target current value corresponds to, and whether the intake valve 4a or the exhaust valve 4b. It can be determined whether it corresponds.

  Also, based on ID1 added to the target current value, which one of the two cylinders belonging to each cylinder group (# 1 &# 4, # 2 &# 3) corresponds to the target current value (# 1? # 4, or # 2 or # 3), in other words, which valve is to be opened / closed (during the valve opening period) is determined. More specifically, in FIG. 9, for example, when ID1 added to the target current value of # 1 / # 4-IN is 0, the valve to be opened / closed (during the valve opening period) is cylinder # 1. When the intake valve 4a of # 4 is determined to be fully closed and ID1 is 1, the opening / closing operation (the valve in the valve opening period) is the intake valve 4a of # 4. Yes, it is determined that # 1 intake valve 4a is fully closed.

  Further, the ID2 added to the target current value identifies which coil (the upper coil 43a or the lower coil 44a) is to be supplied with current, as in the ID of the above-described example.

  In the control unit 8, the CPU 800 writes the target current values in the memory 801 in a predetermined order, and also writes ID1 and ID2 of each target current value, and the error detection code (CRC) is serial communication. Generated when the module (SCM) 803 transmits the target current value.

  FIG. 10 is a flowchart showing a processing example (program example) executed by the current value determination unit 901 of the drive unit 9 that operates based on the transfer frame format shown in FIG.

  When the current value determination unit 901 receives the target current value, the current value determination unit 901 executes this process on the intake valves 4a and the exhaust valves 4b of the cylinders # 1, # 2, # 3, and # 4, and the upper coil 43a of each valve. The target current value of the lower coil 44a is determined.

  First, the current value determination unit 901 adds ID1 added to the target current value (the target current value for the cylinder group consisting of cylinders # 1 &# 2 if ID1 is 0, the cylinder consisting of cylinders # 4 &# 3 if ID1 is 1). It is determined whether or not the valve has newly received the target current value from the target current value for the group, in other words, whether or not the valve should change the target current value (step 1001). In this case, since only four target current values are sent at a time, the target current value is given to only half of the eight intake / exhaust valves 4a and 4b in total. For a valve that has not received a new target current value, both the target current value (IcomUP) of the upper coil 43a and the target current value (IcomLW) of the lower coil 44a are maintained at the same value as the previous time (step 1002). This can be, for example, a valve that maintains the fully closed state. In this case, the target current value (IcomUP) of the upper coil 43a is maintained at the holding current value, and the target current value (IcomLW) of the lower coil is “0”. "Will be maintained.

  On the other hand, for a valve that has newly received the target current value, the current value determination unit 901 determines whether the target current value corresponds to either the upper coil 43a or the lower coil 43b from ID2 added to the target current value. (Step 1003).

  If the target current value corresponds to the upper coil 43a, the target current value (IcomUP) of the upper coil 43a is changed to the newly received target current value, and the target current value (IcomLW) of the lower coil 44a is set to “0”. Then, the same processing as in the above-described example (FIG. 8) is performed (step 1004).

  On the other hand, if the target current value corresponds to the lower coil 44a, the target current value (IcomUP) of the upper coil 43a is set to “0”, and the target current value (IcomLW) of the lower coil is set to the newly received target current value. Then, the same processing as in the above-described example (FIG. 8) is performed (step 1005).

  Thus, in this example, since ID1 and ID2 are added to the target current value, the target current value to be transmitted from the control unit 8 to the drive unit 9 is four cylinders # 1, # 2, # 3, # Of the four intake valves 4a and the exhaust valves 4b, only the intake valves 4a for the two cylinders and the exhaust valves 4b for the two cylinders may be used, and only one of the upper coil 43a and the lower coil 44a of each valve. It's okay. In other words, it is only necessary to transfer the target current value for the valve to be opened / closed (in the valve opening period) among the intake / exhaust valves whose valve opening periods do not overlap. Thus, the number of target current values to be transferred to ¼ can be reduced to ¼ (four), and the data transfer amount per time can be greatly reduced. Therefore, the transfer time of the target current value from the control unit 8 to the drive unit 9 can be shortened, and thereby the control cycle can be shortened. As a result, the response is improved and the control accuracy is improved. Etc. can be achieved.

  In the above-described embodiment, an example in which the present invention is applied to the internal combustion engine 1 in which four in-line four cylinders are provided with one intake valve 4a and one exhaust valve 4b has been described. It can be applied to an engine having more than cylinders. Similarly, the present invention can be applied to an engine provided with two or more intake valves and exhaust valves in each cylinder.

  Further, a plurality of serial communication modules (SCM) 803, serial ports 900, and serial transmission paths 806 may be prepared, and the target current values may be divided into a plurality of groups and transmitted in parallel. Thereby, the transfer time of the target current value can be further shortened.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows one Embodiment of the electromagnetically driven valve control apparatus which concerns on this invention with the principal part of the internal combustion engine to which it is applied. The schematic sectional drawing which shows the structure of the electromagnetically driven valve as an intake valve shown by FIG. The block diagram which shows the structure of the control unit shown by FIG. The block diagram which shows the structure of the drive unit shown by FIG. The time chart which shows the opening / closing operation | movement of the intake valve and exhaust valve with which 4 cylinders were equipped. A time chart showing the relationship between the lift amount of the intake valve, the target current value (IcomUP) of the upper coil of the valve, and the target current value (IcomLW) of the lower coil. The figure which shows an example of the transfer frame format for transmitting a target electric current value to a drive unit from a control unit. The flowchart which shows the process of the electric current value determination part of the drive unit which operate | moves based on the transfer frame format shown by FIG. The figure which shows the other example of the transfer frame format for transmitting a target electric current value from a control unit to a drive unit. The flowchart which shows the process of the electric current value determination part of the drive unit which operate | moves based on the transfer frame format shown by FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Electromagnetic drive valve control apparatus, 3 ... Piston, 4a ... Electromagnetic drive valve (intake valve), 4b ... Electromagnetic drive valve (exhaust valve), 5 ... Intake port, 5 ... Exhaust port, 7 ... Spark plug , 8 ... Control unit, 9 ... Drive unit, # 1, # 2, # 3, # 4 ... Cylinder, 43a ... Upper coil, 44a ... Lower coil, 901 ... Current value determination unit

Claims (5)

A control device for an electromagnetically driven valve that controls an electromagnetically driven valve that opens and closes an intake valve and an exhaust valve disposed in each cylinder of an internal combustion engine by an electromagnetic coil,
Control means for setting a target current value to be supplied to each electromagnetic coil; and drive means for energizing and driving the electromagnetic coil based on the target current value set by the control means. The target current value for the electromagnetic coil to be energized and the identifier for identifying whether the target current value corresponds to the opening or closing electromagnetic coil in the electromagnetically driven valve are predetermined by serial communication The control device for an electromagnetically driven valve, wherein the electromagnetic wave is transmitted in order to the driving means, and the driving means is configured to select an electromagnetic coil to be energized based on the received identifier.   The driving means is configured to energize and drive an electromagnetic coil corresponding to the received identifier based on a newly received target current value, and stop energization to the electromagnetic coil not corresponding to the received identifier. The control device for an electromagnetically driven valve according to claim 1.   The drive means drives the energization of the electromagnetic coil corresponding to the received identifier based on the newly received target current value, and drives the energization of the electromagnetic coil not corresponding to the received identifier based on the previously received target current value. The electromagnetically driven valve control device according to claim 1, wherein the control device is an electromagnetically driven valve. A control device for an electromagnetically driven valve that controls an electromagnetically driven valve that opens and closes an intake valve and an exhaust valve disposed in each cylinder of an internal combustion engine by an electromagnetic coil,
Control means for setting a target current value to be supplied to each electromagnetic coil; and drive means for energizing and driving the electromagnetic coil based on the target current value set by the control means. A first identifier for identifying a target current value of an opening or closing electromagnetic coil to be energized, an electromagnetic driving valve to be opened / closed, and an electromagnetic driving valve to be energized; And a second identifier for identifying whether the target current value corresponds to the opening or closing electromagnetic coil in the electromagnetically driven valve, and to the driving means in a predetermined order by serial communication The driving means energizes and drives the electromagnetic coil of the electromagnetically driven valve that does not correspond to the received first identifier based on the previously received target current value, and the electromagnetically driven valve that corresponds to the received first identifier electromagnetic The electromagnetic coil corresponding to the received second identifier is energized and driven based on the newly received target current value, and the energization to the electromagnetic coil not corresponding to the received second identifier is stopped. A control device for an electromagnetically driven valve.   The control means includes a target current value for an intake valve of a plurality of cylinder groups consisting of a plurality of cylinders that do not overlap with each other and a plurality of cylinders that do not overlap with each other. A target current value for the exhaust valve of each cylinder group is set, and the target current value of the plurality of cylinder groups consisting of a plurality of cylinders whose valve opening periods of the electromagnetically driven valves partially overlap is set to the target current value. 5. The control device for an electromagnetically driven valve according to claim 4, wherein a first identifier for identifying which one corresponds is added.

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