JP2006304473A - Vehicle component drive control circuit and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle component drive control circuit and a manufacturing method therefor, capable of reducing noise caused by PWM control. <P>SOLUTION: A specific frequency f1 is determined for each steering system assembly by delivery inspection to write the specific frequency f1 on EEPROM80 at that time, thus improving workability more than in separately manufacturing data ROM of the specific frequency f1 before mounting it. An ECU60 manufactured in this way performs PWM control using a rectangular pulse P of the specific frequency f1 deviated from a resonance frequency of the steering system assembly to prevent resonance in a vehicle, thus reducing noise caused by PWM control. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle component drive control circuit that performs PWM control of a drive current to an electric device mounted on a vehicle, and a manufacturing method thereof.

2. Description of the Related Art Conventionally, as this type of vehicle component drive control circuit, one that performs PWM control of an excitation current (drive current) to an unlocking solenoid of an actuator mounted on a vehicle is known (see, for example, Patent Document 1).
JP 2003-205848 (paragraphs [0002] and [0044], FIG. 1)

  However, the above-described conventional vehicle component drive control circuit has a problem that an abnormal noise having the same frequency as that of the rectangular pulse used for the PWM control is generated.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a vehicle component drive control circuit capable of reducing noise caused by PWM control and a manufacturing method thereof.

  In order to achieve the above object, a vehicle component drive control circuit according to the invention of claim 1 is a vehicle component drive control circuit that performs PWM control of a drive current to an electric device mounted on a vehicle. Is provided with a parameter storage memory in which data can be written, and a specific frequency deviating from the resonance frequency of the vehicle or vehicle component is stored in the parameter storage memory, and a rectangular pulse is acquired at the specific frequency acquired from the parameter storage memory. This is characterized in that it is configured to generate PWM and perform PWM control.

  A vehicle component drive control circuit according to a second aspect of the present invention is a vehicle component drive control circuit that performs PWM control of a drive current to an electric device mounted on a vehicle, and includes a plurality of types of frequencies and an identifier for identifying them. A choice storage memory stored as a set and a parameter storage memory in which data can be written while being mounted on the vehicle component drive control circuit are provided, and out of the resonance frequency of the vehicle or vehicle component among a plurality of types of frequencies The frequency identifier is stored in the parameter storage memory, the identifier is acquired from the parameter storage memory, the frequency corresponding to the identifier is acquired from the option storage memory, and a rectangular pulse is generated at the frequency to perform PWM control. It has the characteristics in that place.

  According to a third aspect of the present invention, there is provided a vehicle component drive control circuit manufacturing method in which a specific frequency deviating from a resonance frequency of a vehicle or a vehicle component is stored in a parameter storage memory, and the specific frequency obtained from the parameter storage memory is stored. In a manufacturing method of a vehicle component drive control circuit that generates a rectangular pulse and performs PWM control of a drive current to an electric device mounted on the vehicle, data is written while the parameter storage memory is mounted on the vehicle component drive control circuit. Resonance frequency measurement step for measuring the resonance frequency for each vehicle or each vehicle component, a specific frequency determination step for determining a specific frequency deviating from the resonance frequency for each vehicle or each vehicle component, and specifying In the data writing process of writing the specific frequency determined in the frequency determination process to the parameter storage memory With a butterfly.

  According to a fourth aspect of the present invention, there is provided a method of manufacturing a vehicle component drive control circuit, wherein a plurality of types of frequencies and identifiers for identifying them are set and stored in a choice storage memory, and a predetermined identifier is stored in a parameter storage memory. And storing an identifier from the parameter storage memory and obtaining a frequency corresponding to the identifier from the option storage memory, generating a rectangular pulse at the frequency, and generating a drive current to an electric device mounted on the vehicle. In a manufacturing method of a vehicle component drive control circuit that performs PWM control, a parameter storage memory is configured so that data can be written in a state where the parameter storage memory is mounted on the vehicle component drive control circuit, and a resonance frequency for each vehicle or each vehicle component is measured. Of the plurality of types of frequencies stored in the resonance frequency measurement step and the option storage memory, each vehicle or each vehicle structure Having an identifier determination step of determining an identifier of a frequency that deviates from their resonant frequency for each component, the characterized in that performing the data writing step of writing the identifier determined by the identifier determination process in the parameter storage memory.

[Invention of Claim 1]
According to the configuration of the first aspect, PWM control is performed using a rectangular pulse having a specific frequency that deviates from the resonance frequency of the vehicle or vehicle components, so that resonance in the vehicle is prevented and noise caused by PWM control is reduced. can do. Here, since the parameter storage memory is configured to be able to write data while being mounted on the vehicle component drive control circuit, the specific frequency is determined by the shipping inspection, and the specific frequency is immediately stored in the parameter storage memory. Can write. As a result, the working efficiency is improved as compared with a case where a data ROM having a specific frequency is separately manufactured and then mounted.

[Invention of claim 2]
According to the configuration of claim 2, a frequency deviating from the resonance frequency of the vehicle or the vehicle component among a plurality of types of frequencies is acquired based on the identifier stored in the parameter storage memory, and a rectangular pulse is generated at that frequency. Then, PWM control is performed. As a result, PWM control can be performed using a rectangular pulse having a frequency that deviates from the resonance frequency of the vehicle or vehicle component, resonance in the vehicle can be prevented, and noise resulting from PWM control can be reduced. . Here, since the parameter storage memory is configured to be able to write data in a state where it is mounted on the vehicle component drive control circuit, an identifier relating to a frequency for preventing resonance is determined by a shipping inspection, The identifier can be written to the parameter storage memory. Thereby, the working efficiency is improved as compared with the case where the data ROM storing the identifier is separately manufactured and then mounted.

[Invention of claim 3]
According to the configuration of the third aspect, the resonance frequency for each vehicle or each vehicle component is measured, and the specific frequency excluded from these resonance frequencies is determined. And the specific frequency according to each vehicle or each vehicle component is written in the parameter storage memory mounted in the vehicle component drive control circuit. As described above, according to the manufacturing method of the present invention, the specific frequency is determined by the shipping inspection, and the specific frequency is written in the parameter storage memory on the spot. Therefore, when the data ROM having the specific frequency is separately manufactured and then mounted. Compared with work efficiency. According to the vehicle component drive control circuit manufactured as described above, PWM control is performed using a rectangular pulse having a specific frequency that deviates from the resonance frequency of the vehicle or vehicle component, thereby preventing resonance in the vehicle. , Noise caused by PWM control can be reduced.

[Invention of claim 4]
According to the fourth aspect of the present invention, the vehicle component drive control circuit is provided with the option storage memory storing a plurality of types of frequencies and identifiers for identifying them as a set, and the resonance frequency for each vehicle is measured. Then, an identifier of a specific frequency that is out of the resonance frequency among the plurality of types of frequencies stored in the option storage memory is determined. And the identifier is written in the parameter storage memory mounted in the vehicle component drive control circuit. As described above, according to the manufacturing method of the present invention, a predetermined frequency is determined by shipping inspection, and an identifier corresponding to the frequency is written in the parameter storage memory on the spot. Therefore, a data ROM storing the identifier is separately manufactured. Work efficiency is improved compared to the case of mounting from above. According to the vehicle component drive control circuit manufactured as described above, PWM control is performed using a rectangular pulse having a specific frequency that deviates from the resonance frequency of the vehicle or vehicle component, thereby preventing resonance in the vehicle. , Noise caused by PWM control can be reduced.

[First Embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment according to the invention will be described with reference to FIGS. A rack 12 is passed between a pair of steered wheels 11 and 11 in the vehicle 10 shown in FIG. The rack 12 is covered with a rack case 12C, and the rack case 12C is fixed to the vehicle body 14. And the rack 12 moves directly in the rack case 12C, and the steered wheels 11 and 11 steer.

  A pinion 15 attached to the lower end portion of the steering shaft 16 is engaged with a middle portion in the longitudinal direction of the rack 12. Further, the upper end portion of the steering shaft 16 is connected to the handle 17 via an actuator 18.

  As shown in FIG. 2, the actuator 18 includes a differential reduction gear 20 on the lower end side and a motor 25 for driving the reduction gear 20 on the upper end side. The speed reducer 20 includes an input rotary shaft 21 and an output rotary shaft 22 arranged coaxially. The rotor 26 of the motor 25 is connected to the input rotary shaft 21, and the steering shaft 16 is connected to the output rotary shaft 22. Further, the stator 27 of the motor 25 is fixed to the assembly sleeve 19 together with the main body portion 23 of the speed reducer 20.

  A connection housing 30 is fixed to the upper end portion of the assembly sleeve 19, and the connection housing 30 covers the upper side of the motor 25. A handle connecting shaft 17J extending from the center of the handle 17 is fixed to the connecting housing 30. Accordingly, when the steering wheel 17 is steered, if the rotor 26 of the motor 25 does not rotate, the steering shaft 16 rotates integrally with the steering wheel 17, and if the rotor 26 rotates, the steering shaft 16 rotates relative to the steering wheel 17. To do. That is, the rotation angle of the steering shaft 16 with respect to the steering angle of the handle 17 can be changed by rotating the rotor 26 of the motor 25. Further, when the rotor 26 rotates, the rotation is decelerated by the speed reducer 20 and transmitted to the steering shaft 16.

  An annular cable case 31 is assembled to the upper portion of the connection housing 30, and power is supplied to the motor 25 and a solenoid 46 (see FIG. 3, which corresponds to the “electric device” according to the present invention) described later. A spiral cable 34 is accommodated.

  A rotating shaft 26 </ b> S provided in the rotor 26 protrudes from the upper surface of the motor 25. And the lock holder 40 is being fixed to the rotating shaft 26S so that integral rotation is possible. As shown in FIG. 3, the lock holder 40 has a ring shape, and a plurality of concave and convex engaging portions 40A are formed on the peripheral surface thereof. A lock arm 41 is provided on the upper end surface of the motor 25 to engage the concave and convex engaging portion 40A of the lock holder 40 and prevent the rotor 26 from rotating.

  The lock arm 41 is pivotally supported by a support column 42 standing upright from the upper end surface of the motor 25. Specifically, the column 42 passes through a position closer to one end of the lock arm 41, and the tip of the lock arm 41 on the side extending relatively long from the penetrating portion of the column 42 is directed toward the lock holder 40. The stop protrusion 41A protrudes.

  A torsion spring 44 is attached to the lock arm 41. The torsion spring 44 has a coil spring structure, and one end of a spring wire constituting the coil spring is locked to the end surface of the support post 42, and the other end is locked to the lock arm 41. The lock arm 41 is biased to the lock position by the elastic force of the torsion spring 44. Then, in a state where the lock arm 41 is located at this lock position (the state shown in FIG. 3), the locking protrusion 41A engages with the concave and convex engaging portion 40A of the lock holder 40, and the rotor 26 is prevented from rotating. .

  A linear drive source 45 is provided on the upper surface of the motor 25 in order to move the lock arm 41 to the unlock position against the elastic force of the torsion spring 44. The linear drive source 45 is configured to linearly move the plunger 47 by excitation of the solenoid 46. The tip of the plunger 47 is connected to the end of the lock arm 41 that extends to the outside of the column 42. When the solenoid 46 is excited, the plunger 47 moves linearly so as to be pulled into the back side of the hollow portion of the solenoid 46. As a result, the lock arm 41 rotates counterclockwise in FIG. As a result, the lock arm 41 reaches the lock release position, the engagement between the locking projection 41A and the concave / convex engagement portion 40A is released, and the rotor 26 becomes rotatable. On the other hand, when the excitation of the solenoid 46 is stopped, the plunger 47 can move freely in the solenoid 46, and the elastic force of the torsion spring 44 causes the plunger 47 together with the lock arm 41 to return to the original position ( Return to the locked position.

  Excitation of the solenoid 46 and driving of the motor 25 are performed by an ECU 60 (see FIG. 1, where ECU is an abbreviation for Electric Control Unit). The ECU 60 corresponds to a “vehicle component drive control circuit” according to the present invention, and is connected to the solenoid 46 and the winding of the motor 25 via the spiral cable 34. As shown in FIG. 1, the ECU 60 includes a CPU 63, ROM 64, RAM 65, EEPROM 80 (corresponding to “parameter storage memory” according to the present invention), a motor drive circuit 66, and a solenoid excitation circuit 67. Furthermore, the steering angle of the steering wheel 17 detected by the steering angle sensor 61, the vehicle speed detected by the vehicle speed sensor 62, and the on / off signal of the ignition switch 70 are taken into the ECU 60. Here, if the ratio of the steering angle θ1 of the steering wheel 17 to the vehicle body 14 and the rotation angle θ2 of the steering shaft 16 to the vehicle body 14 is the steering transmission ratio R (= θ2 / θ1), the ECU 60 R is changed according to the vehicle speed.

  Specifically, the ROM 64 provided in the ECU 60 stores a map (not shown) in which the vehicle speed and the steering transmission ratio R are associated with each other. Then, the steering transmission ratio R is determined based on the detection result of the vehicle speed sensor 62 and this map. Next, the target rotation angle θ3 of the steering shaft 16 is calculated from the steering angle θ1 of the steering wheel 17 detected by the steering angle sensor 61 and the steering transmission ratio R, and the actual rotation angle θ2 of the steering shaft 16 is calculated as the target rotation angle. In order to coincide with θ3, a drive current is supplied from the motor drive circuit 66 to the motor 25 through the spiral cable 34 to rotate the rotor 26.

  The map is set so that the steering transmission ratio R decreases as the vehicle speed increases. As a result, in the low speed range, the steered wheels 11 can be turned by a slight steering operation, and the turning performance is improved. On the other hand, in a high speed range, so-called sudden steering is restricted, and stable running is possible.

  As shown in FIG. 4, the solenoid excitation circuit 67 is formed by connecting a DC power source 69 and a switch element 68 in series to the solenoid 46 described above. Then, the CPU 63 provided in the ECU 60 executes a lock release program (not shown) to switch the switch element 68 and to flow a drive current for rotating the lock arm 41 to the solenoid 46. At this time, the ECU 60 controls the drive current by PWM control. The EEPROM 80 stores the frequency f of the rectangular pulse P used for PWM control. That is, when the CPU 63 provided in the ECU 60 executes the lock release program, the CPU 63 acquires data of the frequency f from the EEPROM 80, and generates a rectangular pulse P at the frequency f as shown in FIG. Then, the drive current I is controlled by appropriately changing the width of each rectangular pulse P. More specifically, when the lock release program is executed, the data stored in the EEPROM 80 is stored in the timer register 60A in the storage area of the CPU 63 as shown in FIG. The process 60B acquires the data stored in the timer register 60A as the frequency f, and generates a rectangular pulse P having a predetermined width at the frequency f.

  By the way, when the solenoid 46 is excited as described above, it can be a sound source having the same frequency f as the rectangular pulse P used in the PWM control. When the sound generated by the solenoid 46 matches the resonance frequency of the vehicle 10, the sound is amplified and reverberates inside the vehicle. On the other hand, when the frequency of the rectangular pulse P is set to a high frequency, the solenoid 46 can become high temperature. For this reason, for example, the frequency of the rectangular pulse P is limited to a range of 0.3 to 1.5 [kHz]. Further, due to the assembly error of the steering system assembly (corresponding to the “vehicle component” according to the present invention) including the steering shaft 16, the rack 12, and the rack case 12 </ b> C, the frequency that resonates with the solenoid 46 differs for each steering system assembly. .

  In view of these circumstances, in this embodiment, when the steering system assembly is completed, as shown in FIG. 6A, at the time of shipping inspection, the inspection device 81 is connected to the EEPROM 80, and the frequency is sequentially changed and written to the EEPROM 80. The lock release program is executed to excite the solenoid 46 and measure the volume. Then, the resonance volume for each frequency is compared to identify the resonance frequency for each steering system assembly (corresponding to the “resonance frequency measurement step” according to the present invention).

  Next, the specific frequency f1 deviating from the resonance frequency of the steering system assembly is determined (corresponding to the “specific frequency determination step” according to the present invention). Specifically, for example, 0.3 [kHz] is added to or subtracted from the resonance frequency, and the specific frequency f1 is determined so as to be within the range of 0.3 to 1.5 [kHz]. Then, the inspection device 81 writes the specific frequency f1 in the EEPROM 80 (corresponding to the “data writing process” according to the present invention). When the inspection device 81 executes a predetermined program, the inspection and writing of the specific frequency f1 are automatically performed. Thus, the manufacture of the ECU 60 is completed. And this steering system assembly is mounted in a vehicle with ECU60.

  As described above, according to the manufacturing method of the ECU 60 of the present embodiment, the specific frequency f1 for each steering system assembly is determined by the shipping inspection, and the specific frequency f1 is written in the EEPROM 80 on the spot. The work efficiency is improved compared to the case of mounting separately after mounting. And according to ECU60 manufactured in this way, since PWM control is performed using the rectangular pulse P of the specific frequency f1 deviated from the resonance frequency of the steering system assembly, resonance in the vehicle is prevented, and PWM control is performed. The resulting noise can be reduced.

[Second Embodiment]
The present embodiment is a modification of the first embodiment. Hereinafter, only the configuration different from that of the first embodiment will be described, and the same parts as those of the first embodiment will be denoted by the same reference numerals and redundant description will be omitted. In the ROM 64 (corresponding to the “option storage memory” according to the present invention) provided in the ECU 60 of the present embodiment, a plurality of types of frequencies (f10, f11, f12...) Are set with identifiers (for example, identification numbers). Is remembered. The EEPROM 80 stores a predetermined identifier. When the CPU 63 of the ECU 60 executes the lock release program, the EEPROM 80 acquires the identifier from the EEPROM 80, and further acquires the frequency around the same identifier as the identifier from the ROM 64. A rectangular pulse having a predetermined width is generated at the frequency.

  In order to determine the identifier to be written to the EEPROM 80, the inspection device 81 sequentially changes the identifiers corresponding to a plurality of types of frequencies (f10, f11, f12...), Writes them to the EEPROM 80, and executes the unlock program. The solenoid 46 is excited and the volume is measured. Then, the resonance volume for each frequency is compared to identify the resonance frequency for each steering system assembly. Then, an identifier having a predetermined frequency deviating from the resonance frequency of the steering system assembly is determined and written to the EEPROM 80. The configuration of the present embodiment described above has the same operational effects as the first embodiment.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

  (1) Although one specific frequency f1 is stored in the EEPROM 80 of the above embodiment, a plurality of specific frequencies deviating from the resonance frequency of the steering system assembly are determined, and the plurality of specific frequencies are stored in the EEPROM. Also good. And you may make it the structure which switches the frequency of a rectangular pulse to the some specific frequency memorize | stored in EEPROM, and performs PWM control.

  (2) In the first embodiment, the resonance frequency for each steering system assembly is specified and written in the EEPROM 80. However, the resonance frequency is measured for each vehicle on which the steering system assembly is mounted, and the identification deviating from the resonance frequency is specified. The frequency may be written in the EEPROM.

  (3) Although the first embodiment includes the EEPROM 80 for storing the specific frequency f1 or the identifier, any memory other than the EEPROM may be used as long as data can be written in the state mounted in the ECU 60. Good.

The conceptual diagram of the vehicle provided with the steering device which concerns on 1st Embodiment of this invention. Actuator side sectional view Top view of the lock mechanism provided in the actuator Circuit diagram of solenoid excitation circuit Waveform diagram showing rectangular pulse shape Block diagram of vehicle parts drive control circuit

Explanation of symbols

10 Vehicle 11 Steering Wheel 46 Solenoid 60 ECU
67 Solenoid excitation circuit 68 Switch element 80 EEPROM

Claims (4)

In a vehicle component drive control circuit that performs PWM control of a drive current to an electric device mounted on a vehicle,
A parameter storage memory capable of writing data in a state of being mounted on the vehicle component drive control circuit is provided, a specific frequency deviating from a resonance frequency of the vehicle or vehicle component is stored in the parameter storage memory, and the parameter storage memory A vehicle component drive control circuit configured to perform the PWM control by generating a rectangular pulse at the specific frequency acquired from In a vehicle component drive control circuit that performs PWM control of a drive current to an electric device mounted on a vehicle,
An option storage memory that stores a plurality of types of frequencies and identifiers for identifying them as a set, and a parameter storage memory that can write data in a state of being mounted on the vehicle component drive control circuit,
Storing the identifier of the frequency out of the resonance frequency of the vehicle or vehicle component among the plurality of types of frequencies in the parameter storage memory;
A vehicle configured to acquire the identifier from the parameter storage memory, acquire a frequency corresponding to the identifier from the option storage memory, generate a rectangular pulse at the frequency, and perform the PWM control. Component drive control circuit. A specific frequency deviating from the resonance frequency of the vehicle or vehicle component is stored in a parameter storage memory, a rectangular pulse is generated at the specific frequency acquired from the parameter storage memory, In the manufacturing method of the vehicle component drive control circuit for PWM control of the drive current,
The parameter storage memory is configured so that data can be written in a state mounted in the vehicle component drive control circuit,
A resonance frequency measuring step for measuring a resonance frequency for each vehicle or each vehicle component;
A specific frequency determining step for determining a specific frequency deviating from the resonance frequency for each vehicle or each vehicle component;
A vehicle component drive control circuit manufacturing method comprising: performing a data writing step of writing the specific frequency determined in the specific frequency determination step into the parameter storage memory. A plurality of types of frequencies and identifiers for identifying them are stored as a set in the option storage memory, the predetermined identifier is stored in the parameter storage memory, and the identifier is acquired from the parameter storage memory. In the method of manufacturing a vehicle component drive control circuit that obtains a frequency corresponding to the identifier from the option storage memory, generates a rectangular pulse at the frequency, and performs PWM control of a drive current to an electric device mounted on the vehicle.
The parameter storage memory is configured so that data can be written in a state mounted in the vehicle component drive control circuit,
A resonance frequency measuring step for measuring a resonance frequency for each vehicle or each vehicle component;
An identifier determination step for determining an identifier of a frequency deviating from the resonance frequency for each vehicle or for each vehicle component among a plurality of types of frequencies stored in the option storage memory;
A method for manufacturing a vehicle component drive control circuit, comprising: a data writing step of writing the identifier determined in the identifier determination step into the parameter storage memory.

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