JP2013102652A - Control device for electrically movable seats - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for electrically movable seats that restrains outward emission of PWM noise, arising when motors are started or stopped, as vehicle noise while reducing the total length of working time of every motor to be driven.SOLUTION: A control device comprises a plurality of motors provided to make the shape or position of a seat variable; PWM drive means of which one unit is provided for each motor and PWM-drives the motor; and speed control means that performs speed control to gradually vary the speed of each motor at the time of starting and stopping the motor by the PWM drive means. When the speed control of at least one of the motors at the time of its stopping and that of other motors at the time of their starting are performed, the speed control means brings into coincidence the timing of speed control of each of the two of more motors with that of others, and the PWM drive means makes the phases of the two or more motors, when subjecting them to PWM control, reverse to each other.

Description

  The present invention relates to a control device for an electric seat, and in particular, gradually drives a plurality of motors provided for changing the shape or position of the seat by PWM driving, and gradually increases the motor speed when starting or stopping each motor. The present invention relates to a control device for an electric seat suitable for executing speed control to be changed.

  Motors that change the shape and position of the seat include a motor that slides the seat back and forth, a motor that reclines the seat, a motor that lifts the seat up and down, and a seat back that is folded Motors for tilting the side support part of the seat back part. Each of these seat motors needs to operate while supporting a seated person. In this regard, in order to eliminate the anxiety about the seated person and ensure comfort, it is necessary to reduce the shock transmitted to the seated person when the motor is started or stopped when the motor is started or stopped. It is done.

  2. Description of the Related Art Conventionally, an electric seat controller that drives a sheet motor by PWM (Pulse Width Modulation) is known (see, for example, Patent Document 1). This control device executes speed control for gradually increasing the motor speed to a desired speed when the motor is started, and gradually decreasing the motor speed to zero when the motor is stopped. If such speed control is performed, it is avoided that the motor is started and stopped rapidly in a short time. Therefore, according to the control device described above, it is possible to reduce a shock to the seated person when starting and stopping the motor.

  Further, as described above, there are a plurality of types of motors for changing the shape and position of the sheet. Each seat motor needs to be driven while supporting the seated person. Therefore, in order to drive each seat motor, it is necessary to flow a large operating current to generate a high torque. It is. Furthermore, the seat motor is often driven when the vehicle is not driven and the vehicle engine is not driven. In this regard, if an attempt is made to drive a plurality of seat motors simultaneously while the vehicle is stopped, an excessive current needs to flow from the in-vehicle battery. Therefore, in order to avoid such a situation, the plurality of seat motors are driven. In some cases, each seat motor is driven one by one at different times.

JP-A-4-237645

  However, in the case where the driving of each seat motor for which the above speed control is performed at the time of start and stop is performed one by one at a time, the speed becomes completely zero when one seat motor is stopped. After that, if the speed of the next sheet motor starts to increase from zero, the driving of the last sheet motor is completed after the driving of the first sheet motor among all the sheet motors to be driven is started. I spend a lot of time to do it. Further, since each seat motor is PWM-driven, when each seat motor is started or stopped, PWM noise is generated at each speed control timing and released to the outside as vehicle noise.

  The present invention has been made in view of the above points, and PWM noise generated when starting or stopping the motor is released to the outside as vehicle noise while reducing the total operating time of all the motors to be driven. An object of the present invention is to provide a control device for an electric seat that can suppress the occurrence of the problem.

  The above object is to provide a plurality of motors provided for changing the shape or position of a sheet, PWM drive means provided for each of the motors, and PWM driving the motors, and activation of the motors by the PWM drive means. Speed control means for executing speed control for gradually changing the speed of the motor at the time of stopping and stopping, and the speed control at the time of stopping at least one of the motors and the speed control at the time of starting other motors Are executed, the speed control means matches the timings of the speed control with respect to the two or more motors, and the PWM drive means PWM drives the two or more motors. This is achieved by the electric seat control device in which the phases are reversed.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the PWM noise which generate | occur | produces at the time of starting of a motor or a stop is discharge | released outside as vehicle noise, shortening the total operation time of all the motors which should be driven.

It is a block diagram of the control apparatus for electric seats which is one Example of this invention. It is a time chart of the motor operation | movement implement | achieved when three motors drive continuously in time in the control apparatus for electric sheets of a present Example. It is a figure showing the PWM output from a control part to two motors when the speed of two motors is controlled in the electric seat control device of the present embodiment. It is a time chart of the motor operation | movement implement | achieved when three motors are driven continuously in time in the control apparatus for electric sheets of contrast compared with a present Example. It is a figure showing the mechanism in which PWM noise generate | occur | produces in the control apparatus for electric sheets of contrast with a present Example. It is a block diagram of the control apparatus for electric seats of the modification of this invention.

  Hereinafter, specific embodiments of an electric seat control device according to the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration diagram of an electric seat control device 10 according to an embodiment of the present invention. The electric seat control device 10 of the present embodiment includes, for example, a plurality of motors 12 (two motors 12A and 12B shown in FIG. 1) provided to change the shape and position of a seat mounted on a vehicle. It is a device that controls).

  The motor 12 includes a motor for sliding the seat back and forth, a motor for reclining the seat, a motor for lifting the seat up and down, a motor for folding the seat back portion, and a seat back portion. There are a plurality of motors such as a motor for tilting the side support portion. Each motor 12 generates torque for changing the shape or position of the sheet. The shaft of each motor 12 is meshed with the movable part on the seat side via a speed reducer. Torque generated by the motor 12 is transmitted to the movable portion on the seat side via the speed reducer.

  A vehicle power supply 14 is electrically connected to the motor 12. The vehicle power supply 14 is a DC power supply, and is, for example, an in-vehicle battery so that the shape and position of the seat can be changed even when the vehicle is turned off. Each motor 12 is driven by power supplied from the vehicle power supply 14 and generates the torque described above. Each motor 12 is configured to be able to switch the driving direction by switching the direction of the flowing current.

  The electric seat control device 10 includes a control unit 16 mainly composed of a microcomputer. An operation switch 18 that is operated by a vehicle occupant to electrically change the shape and position of the seat is electrically connected to the control unit 16. The operation switch 18 is provided corresponding to each motor 12. The control unit 16 activates or stops the corresponding motor 12 in accordance with the operation of the operation switch 18 by the vehicle occupant. The control unit 16 may start or stop the motor 12 so that the seat shape and the seat position stored in the memory are realized in accordance with a predetermined switch operation by the vehicle occupant.

  The control unit 16 performs PWM driving for each motor 12 so that the ON / OFF duty ratio of power supply from the vehicle power supply 14 can be varied. Each motor 12 is PWM driven according to an instruction from the control unit 16. Further, the control unit 16 executes speed control for gradually changing the speed of the motor 12 by gradually changing the duty ratio in PWM driving when the motor 12 is started and stopped. The speed of each motor 12 is changed by changing the duty ratio in PWM driving.

  The electric seat control device 10 also includes a switching element 20 that controls the driving of the motor 12. The switching element 20 is a MOS-FET as a semiconductor element. The switching element 20 is provided for each motor 12 (in FIG. 1, a switching element 20A corresponding to the motor 12A and a switching element 20B corresponding to the motor 12B are shown).

  Each switching element 20 has a configuration in which a source terminal is grounded and a drain terminal is connected to the motor 12. The control unit 16 is electrically connected to the gate terminal of the switching element 20. The control unit 16 drives the motor 12 by PWM by controlling on / off of the switching element 20. The motor 12 is driven by being supplied with electric power from the vehicle power source 14 when the switching element 20 is turned on, and is stopped when the electric power supply from the vehicle power source 14 is stopped when the switching element 20 is turned off. Is done.

  Next, operation | movement of the control apparatus 10 for electric seats of a present Example is demonstrated using FIG.2 and FIG.3.

  FIG. 2 shows a case where three motors 12 (A motor, B motor, C motor in FIGS. 2 and 3) are continuously driven in time in the electric seat control device 10 of this embodiment. Shows a time chart of the motor operation realized. FIG. 3 shows the PWM output from the control unit 16 to the two motors 12 when the speeds of the two motors 12 (A motor and B motor) are respectively controlled in the electric seat control apparatus 10 of the present embodiment. A diagram is shown. FIG. 4 shows a time chart of the motor operation realized when the three motors 12 are continuously driven in time in the proportional electric seat control device compared with the present embodiment. FIG. 5 is a diagram illustrating a mechanism in which PWM noise is generated in the control device for an electric seat in comparison with the present embodiment.

  In the present embodiment, when the plurality of motors 12 are to be driven, the control unit 16 seems to prevent two or more of the motors to be driven from being simultaneously supplied with power from the vehicle power supply 14. That is, drive control is performed so that each of the motors 12 to be driven is supplied with power from the vehicle power supply 14 and the motors 12 are driven one by one at different times. According to the drive control when the plurality of motors 12 are driven, an excessive current for simultaneously driving two or more motors 12 flows from the vehicle power supply 14 when the vehicle is not driven and the vehicle is stopped. Is avoided. For this reason, the system design on the assumption that an excessive current can flow from the vehicle power supply 14 is not required, and the system for changing the shape and position of the seat can be simplified.

  In addition, the control unit 16 executes slow start control that gradually increases the speed to a desired speed as speed control when the motor 12 is started, and slows the speed that gradually decreases to zero when the motor 12 is stopped. Execute stop control. In the slow start control, the time required for the speed of the motor 12 to increase from zero to a desired speed (hereinafter referred to as a speed increase time) is determined in advance, and in the slow stop control, the speed of the motor 12 is increased. The time required to decrease from a desired speed to zero (hereinafter referred to as speed reduction time) is determined in advance. Furthermore, the speed increase time and the speed decrease time are the same or substantially the same.

  Further, when the control unit 16 drives the plurality of motors 12, as described above, each of the motors 12 to be driven is supplied with power from the vehicle power source 14 one by one, and the drive of each motor 12 takes time one by one. The drive control is performed so as to be performed in a shifted manner. When this drive control is executed, the speed control timings of the two motors 12 that are continuously driven in time are matched as shown in FIG.

  Specifically, with respect to two motors 12 that are continuously driven in time, the timing at which the slow stop control of the motor 12 that performs the stop operation is started, and the slow start control of the motor 12 that performs the start operation are performed. And the timing at which the slow stop control of the motor 12 that performs the stop operation is terminated and the timing at which the slow start control of the motor 12 that is activated is terminated. Match each other. For example, as shown in FIG. 2, when the motor 12 is driven in the order of A motor, B motor, and C motor, the timing of the slow stop control of the A motor and the timing of the slow start control of the B motor are matched, and The timing of the slow stop control of the B motor is matched with the timing of the slow start control of the C motor.

  In such control processing, of the two motors 12 that are continuously driven in time, the timing at which the slow stop control of the motor 12 that performs the stop operation is executed, and the slow start of the motor 12 that performs the start operation The timing at which the control is executed overlaps with each other. For this reason, according to the configuration of the present embodiment, for the two motors 12 that are continuously driven in time, after the slow stop control of the motor 12 that is stopped, the speed of the motor 12 is increased. A contrast configuration in which the slow start control of the motor 12 to be started is started after the slow stop control is completely zero, that is, the speed of the motor 12 starts to increase from zero (control processing shown in FIG. 4). In contrast, when the plurality of motors 12 are driven, among the motors 12 to be driven, the driving of the motor 12 that is driven first after the driving of the motor 12 that is driven first is started is completed. Can be shortened.

  Further, the control unit 16 matches the timings of the speed control with respect to the two motors 12 that are continuously driven as described above, and controls the two speed controls (that is, the slow stop control and the slow start control). When the above two) are executed, the phases when the two motors 12 are PWM-driven are opposite to each other. For example, as shown in FIG. 3, when the speed control timing of the A motor and the speed control timing of the B motor coincide with each other, the OFF timing of the PWM output to the switching element 20 for PWM driving the A motor The on-timing of the PWM output to the switching element 20 for PWM driving of the A motor and the on-timing of the PWM output to the switching element 20 for PWM driving of the B motor are matched. Therefore, the OFF timing of the PWM output to the switching element 20 is matched.

  In such control processing, the switching element 20 corresponding to one motor 12 out of the two motors 12 driven continuously in time is turned on and the switching element 20 corresponding to the other motor 12 is turned on. Since the fall from ON to OFF is performed at substantially the same timing, the speed control of the two motors 12 is performed in the situation where the speeds of the two motors 12 driven continuously in time are controlled at the same timing. The generated PWM noises cancel each other.

  For this reason, according to the configuration of this embodiment, when two motors 12 that are continuously driven in time are speed-controlled at the same timing when starting or stopping, that is, of the two motors 12 is started. When the slow start control with respect to the motor 12 to be executed and the slow stop control with respect to the motor 12 to be stopped are executed at the same timing, the comparison structure in which the phases when the two motors 12 are PWM driven are in phase with each other (see FIG. Unlike the configuration shown in FIG. 5, PWM noise generated by speed control of each motor 12 can be prevented from being amplified and released to the outside as vehicle noise.

  Therefore, according to the electric seat control apparatus 10 of the present embodiment, when the plurality of motors 12 are driven, the total operating time of all the motors 12 to be driven is shortened, and the motors 12 are started or stopped. It is possible to suppress the PWM noise generated at times from being released to the outside as vehicle noise. For this reason, according to the present embodiment, it is possible to reduce the time required to vary the shape and position of the sheet, and to reduce the noise generated at the time of the variation, thereby improving the merchantability of the sheet. It is possible to make it.

  By the way, in the above-described embodiment, the control unit 16 performs PWM driving for each motor 12 so that the “PWM driving means” described in the scope of the claims controls speed control (slow when the motor 12 is started and stopped. The “speed control means” described in the claims is realized by executing stop control or slow start control).

  In the above embodiment, when the plurality of motors 12 are driven, each motor 12 to be driven is supplied with power from the vehicle power supply 14 one by one, and the driving of each motor 12 is shifted one by one. However, the present invention is not limited to this, and two motors 12 to be driven are supplied from the vehicle power source 14 by two or more than that to drive each motor 12. It may be performed by shifting the time one by one or more than that. In this case, the slow stop control is simultaneously performed for two or more motors 12 and the slow start control is simultaneously performed for two or more motors 12, but the slow stop control for two or more motors 12 is performed. The timing of the control and the timing of the slow start control for two or more other motors 12 having the same number as the number of the motors 12 for which the slow stop control is performed may be made to coincide with each other. Two or more other motors having the same number as the number of motors 12 for which the slow start control is executed and the phase when the two or more motors 12 for which the motor is executed are PWM driven and the slow start control is executed. What is necessary is just to make it a phase in mutually performing PWM drive to 12 mutually reverse phase.

  Further, in the above embodiment, the duty ratio is not adjusted according to the temperature when the motor 12 is PWM driven, but may be performed. That is, as shown in FIG. 6, a temperature measurement sensor 30 such as a thermistor is disposed in the vicinity of the switching element 20 in which the temperature voltage characteristic of the on-resistance and the temperature voltage characteristic of the gate capacitance are specified in advance. The characteristics of the switching element 20 based on the temperature and the gate capacitance may be measured, and the duty ratio of the switching element 20 during PWM driving may be finely adjusted so that the PWM noise is canceled out.

  Further, in the above embodiment, the system for changing the shape and position of the seat mounted on the vehicle is used. However, the present invention is not limited to this, and an aircraft other than the vehicle, a railway vehicle, etc. The present invention may be applied to a system that changes the shape and position of a sheet mounted on the vehicle.

DESCRIPTION OF SYMBOLS 10 Electric seat control apparatus 12 Motor 14 Vehicle power supply 16 Control part 20 Switching element

Claims (1)

A plurality of motors provided to change the shape or position of the sheet;
PWM driving means provided for each motor and PWM driving the motor;
Speed control means for executing speed control for gradually changing the speed of the motor when the motor is started and stopped by the PWM driving means,
When the speed control at the time of stopping at least one of the motors and the speed control at the time of starting the other motors are executed, the speed control means is configured to control the speeds of the two or more motors to each other. And the PWM driving means sets the phases for PWM driving the two or more motors to be opposite to each other.

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