JPWO2017038317A1 - Motor drive control device and seat belt motor drive control device - Google Patents

Abstract

Provided is a motor driving control device for a seat belt that can reduce the number of switching elements for driving a motor to three or less with respect to one motor. The seat belt motor drive control device includes a plurality of motors that respectively wind up the plurality of seat belts, and a motor drive unit that drives the plurality of motors. The motor drive unit is provided on each of the plurality of parallel connection lines connecting the power supply side and the ground side, the plurality of switching elements arranged on the high voltage side and the low voltage side, and arranged on the high voltage side. And a plurality of connection paths that connect the connection lines between the switching elements arranged on the low voltage side and the switching elements arranged on the low-voltage side, and the plurality of motors are respectively arranged on the plurality of connection paths.

Description

  The present invention relates to a motor drive control device and a seat belt motor drive control device.

  2. Description of the Related Art Conventionally, there has been known a seat belt motor drive control device that includes an H-type bridge circuit in which a plurality of switching elements and a motor are connected, and controls the rotation of the motor by PWM (pulse width modulation) control of the switching elements. (Patent Document 1).

JP 2010-28878 A

  However, since the invention described in Patent Document 1 requires at least four switching elements for each motor, there is a problem in that the circuit size is increased.

  According to a first aspect of the present invention, there is provided a seat belt motor drive control device including a plurality of motors that respectively wind up the plurality of seat belts, and a motor drive unit that drives the plurality of motors. The motor drive unit is provided on each of the plurality of parallel connection lines connecting the power supply side and the ground side, the plurality of switching elements arranged on the high voltage side and the low voltage side, and arranged on the high voltage side. And a plurality of connection paths that connect the connection lines between the switching elements arranged on the low voltage side and the switching elements arranged on the low-voltage side, and the plurality of motors are respectively arranged on the plurality of connection paths.

  According to the present invention, the number of switching elements for driving a motor can be reduced to 3 or less for one motor.

1 is an overall configuration diagram illustrating a basic configuration of a vehicle including a seat belt retractor control device to which a motor drive control device according to a first embodiment is applied. 1 is a schematic configuration diagram schematically showing a seat belt winding system by a seat belt retractor control device to which a motor drive control device according to a first embodiment is applied. The block diagram which shows schematically the internal structure of the seatbelt retractor control apparatus shown in FIG. FIG. 4 is a circuit diagram showing an internal configuration of a motor drive circuit shown in FIG. 3. The schematic diagram which shows the electric current which flows into a motor drive circuit and both motors at the time of both motors normal rotation of the motor drive circuit shown in FIG. FIG. 5 is a waveform diagram showing signal waveforms at the time of forward rotation of both motors of the motor drive circuit shown in FIG. 4. The schematic diagram which shows the electric current which flows into a motor drive circuit and both motors at the time of both motor reverse rotation of the motor drive circuit shown in FIG. FIG. 5 is a waveform diagram showing signal waveforms when both motors are reverse in the motor drive circuit shown in FIG. 4. FIG. 3 is a flowchart showing the control of the seat belt retractor when one motor of the seat belt retractor control device shown in FIG. The schematic diagram which shows an electric current when one motor of the seatbelt retractor control apparatus shown in FIG. 2 is rotating forward. The schematic diagram which shows an electric current when the other motor of the seatbelt retractor control apparatus shown in FIG. 2 is reversely rotated. The wave form diagram which shows the mode of forward rotation temporary stop control of the seatbelt retractor control apparatus shown in FIG. The wave form diagram which shows the mode of the forward rotation priority control of the seatbelt retractor control apparatus shown in FIG. FIG. 3 is a flowchart showing control of the seat belt retractor when one motor of the seat belt retractor control device shown in FIG. The schematic block diagram which shows schematically the seatbelt winding system by the seatbelt retractor control apparatus with which the motor drive control apparatus which concerns on 2nd Embodiment is applied. The block diagram which shows schematically the internal structure of the seatbelt retractor control apparatus shown in FIG. FIG. 17 is a circuit diagram showing an internal configuration of the motor drive circuit shown in FIG. 16. The schematic block diagram which shows schematically the seatbelt winding system by the seatbelt retractor control apparatus with which the motor drive control apparatus which concerns on 3rd Embodiment is applied. FIG. 19 is a flowchart showing the control of the seat belt retractor when one motor of the seat belt retractor control device shown in FIG. The schematic diagram which shows the electric current when one motor of the seatbelt retractor control apparatus shown in FIG. 18 is rotating forward and the other motor is rotating backward. FIG. 19 is a schematic diagram illustrating a current when one motor of the seatbelt retractor control device illustrated in FIG. 18 is rotating forward and the other motor is rotating reversely, and the current of the rotating motor is controlled.

(First embodiment)
FIG. 1 shows a basic configuration of a vehicle 10 provided with a seat belt retractor control device 15 to which the motor drive control device according to the first embodiment is applied.

  The vehicle 10 includes an obstacle sensor 12 that outputs a signal corresponding to a distance from an obstacle ahead of the vehicle at a front portion thereof. The vehicle 10 includes a collision determination controller 16 that is electrically connected to the obstacle sensor 12. The output signal of the obstacle sensor 12 is transmitted to the collision determination controller 16 through the connection line. The vehicle 10 includes a wheel speed sensor 14 that outputs a signal corresponding to the vehicle speed. The output signal of the wheel speed sensor 14 is transmitted to a collision determination controller 16 that is electrically connected to the wheel speed sensor 14.

  The collision determination controller 16 determines whether or not the vehicle 10 collides with an obstacle based on the transmitted output signals from the obstacle sensor 12 and the wheel speed sensor 14. For example, when the distance from the obstacle obtained from the output signal of the obstacle sensor 12 is shorter than a predetermined value and the vehicle speed obtained from the output signal of the wheel speed sensor 14 is faster than the predetermined value, The collision determination controller 16 determines that the vehicle 10 collides with an obstacle. When the collision determination controller 16 determines that the vehicle 10 collides with an obstacle, the brake assist device 18 and the seat belt retractor control device 15 that are electrically connected to the collision determination controller 16 before the vehicle 10 collides with the obstacle. A command signal is output to.

  The brake assist device 18 that has received the command signal brakes, for example, the vehicle 10 based on the command signal from the collision determination controller 16. The seat belt retractor control device 15 supplies motor drive power to the motors in the seat belt retractors 11A and 11B based on the command signal of the collision determination controller 16, and winds up the seat belts 20A and 20B, for example.

  FIG. 2 schematically shows a take-up system of the seat belts 20A and 20B by the seat belt retractor control device 15 to which the motor drive control device according to the first embodiment is applied.

  This system includes seat belts 20A and 20B, seat belt retractors 11A and 11B for winding and pulling out the seat belts 20A and 20B, motors 21A and 21B provided on the seat belt retractors 11A and 11B, motors 21A, The seat belt retractor control device 15 for winding the seat belts 20A and 20B and releasing the clutch of the mechanical parts by controlling the rotational drive of 21B, and the buckles 24A and 24B are provided. The seat belt retractor control device 15 winds up the seat belts 20A and 20B by driving motors 21A and 21B provided on the seat belt retractors 11A and 11B.

  The winding operation of the seat belts 20A and 20B includes a winding (referred to as “emergency mode”) for the purpose of increasing the restraint force in an emergency to ensure the safety of the passengers PA and PB, and the passengers PA and PB. In order to improve the comfort of the seat, the automatic fitting when the seat belt is attached to the buckles 24A and 24B and the winding for the purpose of automatic storage to the seat belt retractors 11A and 11B when the seat belt is detached from the buckles 24A and 24B ( "Comfort mode"). Furthermore, when a lane departure or a side slip of the vehicle 10 is detected based on the signals from the obstacle sensor 12 and the wheel speed sensor 14, a warning is issued by abruptly winding the seat belts 20A and 21A around the occupants PA and PB. There is also an action to give (called "warning mode").

  FIG. 3 schematically shows an internal configuration of the seat belt retractor control device 15 shown in FIG.

  The seat belt retractor control device 15 receives signals transmitted from the buckle switches 33A and 33B provided as electrical contacts in the buckles 24A and 24B, various actuators such as the brake stroke sensor 32, or data transmitted by the CANBUS communication 31. Based on the above, the motor 21A provided in the seat belt retractor 11A is driven as necessary to wind the seat belt 20A, or the motor 21B provided in the seat belt retractor 11B is driven to drive the seat belt 20B. Is taken up or both of them are taken up.

  The seat belt retractor control device 15 mainly includes a motor drive control system LSI 34 and a motor drive circuit 35. The power supply 30 mounted on the vehicle 10 supplies current to the motor drive control system LSI 34 and the motor drive circuit 35. The motor drive control system LSI 34 has a structure in which a microcomputer (hereinafter referred to as “microcomputer”), a peripheral logic circuit, and an H-bridge drive pre-driver are integrated, and controls the motor drive circuit 35. Specifically, after power is supplied to the motor drive circuit 35, the motor drive control system LSI 34 transmits the motor drive signals 36, 37, 38A, 39A, 38B, 39B to the motor drive circuit 35, whereby The rotational drive of the motors 21A and 21B connected to the motor drive circuit 35 is controlled. The motor drive signals 36, 37, 38A, 39A, 38B, and 39B have a drive capability sufficient to drive the motor drive circuit 35 by a pre-driver in the motor drive control system LSI 34.

  FIG. 4 shows the internal configuration of the motor drive circuit 35 shown in FIG.

  The motor drive signal 36 is the gate of the high side transistor 42, the motor drive signal 37 is the gate of the low side transistor 43, the motor drive signal 38A is the gate of the high side transistor 44A, the motor drive signal 39A is the gate of the low side transistor 45A, and the motor drive signal 38B. Are connected to the gate of the high side transistor 44B, and the motor drive signal 39B is connected to the gate of the low side transistor 45B.

  The high side transistor 42 and the low side transistor 43 are connected in series by a connection line 401 between the power supply 40 and the ground 41. The high-side transistor 44A and the low-side transistor 45A, and the high-side transistor 44B and the low-side transistor 45B are connected in series at connection lines 402 and 403, respectively, and the negative pole of the motor 21A is connected to the respective connection portions via connection paths 406 and 407. The negative pole of the motor 21B is connected. The positive poles of the motors 21A and 21B are connected to the connection portion of the high-side transistor 42 and the low-side transistor 43 via the connection paths 404 and 405 as the same net on the circuit.

  The high frequency noise absorbing capacitors 46 and 47 are disposed between the power supply 40 and the ground 41. As will be described later, the high-side transistor 42 and the low-side transistor 43 need not be switched at high speed by PWM. The high-frequency noise absorbing capacitors 46 and 47 are disposed, for example, in the immediate vicinity of a set of a high-side transistor 44A and a low-side transistor 45A that require high-speed switching by PWM, and a set of a high-side transistor 44B and a low-side transistor 45B.

  By turning ON / OFF the high-side transistors 42, 44A, 44B and the low-side transistors 43, 45A, 45B by the motor drive signals 36, 37, 38A, 39A, 38B, 39B, the current flowing through the motor 21A and the motor 21B is changed. Can be controlled.

  For example, when the high-side transistor 42 is turned on, the low-side transistor 45A is turned on, and the other transistors are turned off, a current flows from the positive pole to the negative pole of the motor 21A, and the motor 21A rotates in the forward rotation direction. In this case, if the low-side transistor 45B is turned ON at the same time, a current flows from the positive pole to the negative pole of the motor 21B, and the motor 21B can be rotated in the forward rotation direction.

  When the low-side transistor 43 is turned on, the high-side transistor 44A is turned on, and the other transistors are turned off, current flows from the negative pole of the motor 21A to the positive pole, and the motor 21A rotates in the reverse direction. In this case, if the high-side transistor 44B is turned on at the same time, a current flows from the minus pole to the plus pole of the motor 21B, and the motor 21B can be rotated in the reverse direction.

  FIG. 5 is a schematic diagram showing the currents flowing in the motor drive circuit and both motors during normal rotation of both motors of the motor drive circuit shown in FIG. 4. The motor drive circuit 35 controls the motors 21A and 21B in the normal rotation direction. The state of current flowing is schematically shown.

  In FIG. 5, with the high-side transistor 42 always on and the low-side transistor 43 always off, a positive-phase PWM signal is given to the motor drive signal 39A, and a reverse-phase PWM signal is given to the motor drive signal 38A. give. A current flows from the path 51 to the path 52 at a timing when the low-side transistor 45A is turned on and the high-side transistor 44A is turned off. A current flows from the path 51 to the path 53 at a timing when the high-side transistor 44A is turned on and the low-side transistor 45A is turned off. That is, a current flows in the forward direction of the motor 21A while regenerating the current on the power source 40 side.

  In the state where the high side transistor 42 is always on, the low side transistor 43 is always off, the PWM signal having a positive phase is given to the motor drive signal 39A, and the PWM signal having the opposite phase is given to the motor drive signal 38A, A positive phase PWM signal is applied to the motor drive signal 39B, and a reverse phase PWM signal is applied to the motor drive signal 38B. At the timing when the low side transistor 45B is turned on and the high side transistor 44B is turned off, a current flows from the path 54 to the path 55. At the timing when the high side transistor 44B is turned on and the low side transistor 45B is turned off, a current flows from the path 54 to the path 56. That is, a current flows in the forward direction of the motor 21B while regenerating the current on the power source 40 side. When a current flows to the motor 21A via the path 51 and a current flows to the motor 21B via the path 54, a current corresponding to two of the motor 21A and the motor 21B (combined current) is supplied to the high side transistor 42. Flows.

  6 is a waveform diagram showing signal waveforms at the time of forward rotation of both motors of the motor drive circuit shown in FIG. 4. Under the control of the motor drive circuit 35, paths 51, 52, 53, 54, The timing when current flows through the paths 55 and 56 is shown. In the following timing diagrams, each transistor is turned on when the motor drive signal is at a high level, and each transistor is turned off when the motor drive signal is at a low level.

  After the high side transistor 42 is turned on by the motor drive signal 36, the motor 21A current flows by the positive phase PWM of the motor drive signal 39A and the reverse phase PWM of the motor drive signal 38A. As shown in FIG. 6, between the ON period of the motor signal 38A and the ON period of the motor drive signal 39A, a period in which both transistors indicated by Tdead are OFF in order to prevent a dead short between the power supply 40 and the ground 41. Insert dead time. Further, as shown in FIG. 6, the motor 21B current can be supplied by applying the positive phase PWM of the motor drive signal 39B and the reverse phase PWM of the motor drive signal 38B. Since PWM signals having different duty ratios can be selected for the motor drive signal 38A and the motor drive signal 38B, the amount of current flowing through the motor 21A and the motor 21B can be individually controlled.

  FIG. 7 is a schematic diagram showing the currents flowing through the motor drive circuit and both motors when the motors of the motor drive circuit shown in FIG. 4 are reversed. Under the control of the motor drive circuit 35, the currents in the reverse direction are supplied to the motors 21A and 21B. It shows the state that is flowing.

  In FIG. 7, with the low-side transistor 43 always on and the high-side transistor 42 always off, a positive phase PWM signal is given to the motor drive signal 38A, and a reverse phase PWM signal is given to the motor drive signal 39A. give. A current flows from the path 72 to the path 71 at a timing when the high-side transistor 44A is turned on and the low-side transistor 45A is turned off. A current flows from the path 73 to the path 71 at the timing when the low-side transistor 45A is turned on and the high-side transistor 44A is turned off. That is, current flows in the reverse direction of the motor 21A while regenerating current on the ground 41 side.

  In a state where the low side transistor 43 is always on, the high side transistor 42 is always off, a PWM signal having a positive phase is given to the motor drive signal 38A, and a PWM signal having a phase opposite to that is given to the motor drive signal 39A, A positive phase PWM signal is applied to the motor drive signal 38B, and a reverse phase PWM signal is applied to the motor drive signal 39B. A current flows from the path 75 to the path 74 at a timing when the high-side transistor 44B is turned on and the low-side transistor 45B is turned off. At the timing when the low side transistor 45B is turned on and the high side transistor 44B is turned off, a current flows from the path 76 to the path 74. That is, current flows in the reverse direction of the motor 21B while regenerating current on the ground 41 side. When a current flows to the motor 21A via the path 71 and a current flows to the motor 21B via the path 74, the current (combined current) corresponding to the motor 21A and the motor 21B is supplied to the low-side transistor 43. Flowing.

  FIG. 8 is a waveform diagram showing signal waveforms when the motors of the motor driving circuit shown in FIG. 4 are rotated in reverse. The paths 71, 72, 73, 74, 75 shown in FIG. , 76 shows the timing when current is passed through the path.

  After the low side transistor 43 is turned on by the motor drive signal 37, the motor 21A current flows in the reverse direction by the positive phase PWM of the motor drive signal 38A and the reverse phase PWM of the motor drive signal 39A. As shown in FIG. 8, between the ON period of the motor signal 39A and the ON period of the motor drive signal 38A, a period in which both transistors indicated by Tdead are OFF in order to prevent a dead short between the power supply 40 and the ground 41. Insert dead time. This is the same as driving on the forward rotation side. Further, as shown in FIG. 8, by providing the positive phase PWM of the motor drive signal 38B and the reverse phase PWM of the motor drive signal 39B, the motor 21B current can flow in the reverse direction. PWM signals having different duty ratios can be selected for the motor drive signal 39A and the motor drive signal 39B. The amount of current flowing through the motor 21A and the motor 21B can be individually controlled as in the case of the forward drive.

  The motor drive control device is one of the legs (a combination of a high-side switching element and a low-side switching element) arranged in series between a power source and a ground (GND) as a circuit configuration for driving two or more motors. In this embodiment, a pair of the high side transistor 42 and the low side transistor 43 is used in common among a plurality of motors. The high-side switching element or the low-side switching element of the commonly used leg is fed with a combined current of the currents that flow to multiple motors, and the amount of current that flows to each motor is adjusted by PWM control of the legs that each motor has individually can do.

  FIG. 9 is a flowchart of processing when a request for reverse rotation control is made with respect to the other motor during forward rotation control of one motor in the seatbelt retractor control device 15 shown in FIG. For the motor drive circuit 35 shown in FIG. 4, in the method described in FIGS. 5, 6, 7, and 8, the motor 21A forward rotation and the motor 21B reverse rotation, or the motor 21A reverse rotation and the motor 21B forward rotation are performed. Cannot be controlled simultaneously. Therefore, in the seat belt retractor control device 15 according to the present embodiment, when a reverse rotation request for the reverse motor comes during the normal rotation of one motor, the seat belt retractor is controlled according to the flow shown in FIG. Yes.

  That is, when a reverse rotation request for the motor 21B is received during the normal rotation of the motor 21A, if the seat belt 20A is in the comfort mode, the forward rotation suspension control for the motor 21A is performed ("forward rotation temporary stop"). Details of “control” will be described later). When a reverse rotation request for the motor 21B is received during the normal rotation of the motor 21A, if the winding of the seat belt 20A is in the emergency mode, the forward rotation priority control of the motor 21A is performed (details of “forward rotation priority control”) Will be described later). The same applies to a case where a reverse rotation request for the motor 21A is received during the forward rotation control of the motor 21B.

  In the seat belt 20A and 20B winding system shown in FIG. 2, the forward rotation of the motor 21A and the motor 21B is used for winding the seat belts 20A and 20B, respectively. On the other hand, the reverse rotation of the motor 21A and the motor 21B is used for the purpose of releasing the clutch of the mechanical parts in the seat belt retractors 11A and 11B. After releasing the mechanical parts by the clutch, the passengers PA and PB can pull out the seat belts 20A and 20B. The release operation of the clutch can be completed in a short time, and the reverse operation of the motor 21A and the motor 21B is completed in a time of about several hundreds of ms.

  In the comfort mode, if there is a request for reverse operation of the other motor during normal rotation of one motor, temporary motor normal rotation is stopped, the other motor is reversely operated, and then motor normal rotation is performed. Resume (this is called “forward rotation pause control”). The temporary stopping time of the forward rotation of the motor is about several hundreds of milliseconds, and the passengers PA and PB do not feel uncomfortable. On the other hand, in the emergency mode, it is important to restrain the passengers PA and PB. During the normal rotation operation of one motor, the reverse rotation operation of the other motor ends the normal rotation operation of one motor. (This is called “forward rotation priority control”).

  FIG. 10 is a schematic diagram showing a current when one motor of the seat belt retractor control device 15 shown in FIG. 2 is rotating forward. FIG. 11 is a schematic diagram showing the current when the other motor of the seat belt retractor control device 15 shown in FIG. 2 is rotating in reverse. FIG. 12 is a waveform diagram showing a state of forward rotation suspension control of the seat belt retractor control device 15 shown in FIG.

  As shown in FIG. 10, in the forward rotation control of the motor 21A, the high-side transistor 42 is turned on, the low-side transistor 45A is controlled by the positive phase PWM, and the high-side transistor 44A is controlled by the reverse phase PWM. Current in the forward direction is caused to flow through the motor 21A. As shown in FIG. 12, during the forward rotation control of the motor 21A, when a request for flowing a current in the reverse rotation direction to the motor 21B is met at the time of Treq1, current control in the forward rotation direction of the motor 21A is temporarily stopped. That is, the high-side transistor 42, the low-side transistor 45A, and the high-side transistor 44A are turned off, and after waiting for Twait1 time, control is performed so that a current in the reverse direction flows through the motor 21B. The Twait 1 time is set such that the mechanical energy of the motor 21A obtained by the normal rotation of the motor 21A is sufficiently attenuated, and even if the low side transistor 43 is switched to ON, the low side transistor 43 is not destroyed.

  During the Trev period shown in FIG. 12, the reverse side of the motor 21B is driven. That is, during this period, as shown in FIG. 11, the low-side transistor 43 is turned on, the high-side transistor 44B is controlled by the positive phase PWM, and the low-side transistor 45B is controlled by the reverse phase PWM. A current in the reverse direction is supplied to 21B. After the reverse rotation operation of the motor 21B is completed, the system waits for Twait 2 hours and resumes the normal rotation control of the motor 21A. The Twait 2 time is set so that the mechanical energy of the motor 21B obtained by the reverse rotation of the motor 21B is sufficiently attenuated and the high-side transistor 42 is not destroyed even if the high-side transistor 42 is switched to ON. . The same applies to forward rotation temporary stop control of the motor 21B when the motor 21B side performs forward rotation control.

  The motor drive control device in the present embodiment performs rectification control using the high-side transistor 42, the low-side transistor 45A, and the high-side transistor 44A, for example, as described above, when a current in the normal rotation direction flows through the motor 21A. Then, the other transistors are set to the off state. When a current in the reverse direction is supplied to the motor 21B, the motor drive control device performs rectification control using, for example, the low-side transistor 43, the high-side transistor 44B, and the low-side transistor 45B, and sets the other transistors to the off state. The motor drive control device can rotate the motors in different rotation directions by switching between a state in which a current in the forward direction flows through the motor 21A and a state in which a current in the reverse direction flows through the motor 21B.

  FIG. 13 is a waveform diagram showing the state of forward rotation priority control of the seat belt retractor control device 15 shown in FIG. 2, and shows the timing when the motor drive circuit 35 performs forward rotation priority control of the motor 21A.

  The state of forward rotation control of the motor 21A when performing forward rotation priority control and the state of reverse rotation control of the motor 21B are the same as in FIGS. 10 and 11, respectively. In the forward rotation priority control of the motor 21A, as shown in FIG. 13, the timing for actually performing the reverse rotation control on the motor 21B side when the reverse rotation control request on the motor 21B side is made differs. That is, in Treq2, even when reverse rotation control on the motor 21B side is requested, the reverse rotation operation of the motor 21B is not performed immediately. After the normal rotation control of the motor 21A is completed, after waiting for Twait 1 hour, the current in the reverse direction is supplied to the motor 21B. Control to flow. The Twait 1 time is a period in which the mechanical energy of the motor 21A obtained by normal rotation of the motor 21A is sufficiently attenuated. The same applies to forward rotation priority control of the motor 21B when the motor 21B side performs forward rotation control.

  FIG. 14 is a flowchart showing the processing of the seatbelt retractor control device 15 when a request for forward rotation of the reverse motor is received during reverse rotation of one motor in the seatbelt retractor control device 15 of the present embodiment. It is.

  In the emergency mode, the seat belt is taken up, that is, the forward rotation side has priority, so the motor that is rotating in reverse is temporarily stopped and the motor that meets the normal rotation request is rotated forward during that time. The details of the control for temporarily stopping the reverse rotation operation and restarting the reverse rotation operation after completion of the forward rotation operation of the reverse motor are the same as those of the forward rotation temporary stop control. In the comfort mode, the winding of the forward rotation is as long as several seconds or more. Therefore, when the reverse rotation operation is resumed after the normal rotation operation is finished, the passengers PA and PB feel uncomfortable. For this reason, priority is given to the reverse rotation operation, and the reverse rotation operation of the reverse motor is performed after the reverse rotation operation is completed. Since the reverse rotation operation is completed within several hundreds of milliseconds, the passengers PA and PB do not feel uncomfortable even if the normal rotation operation is performed after the reverse rotation operation is completed in this way.

According to this embodiment described above, the following operational effects can be obtained.
(1) The seat belt motor drive control device includes a plurality of motors 21A and 21B that wind up the plurality of seat belts 20A and 20B, respectively, and a motor drive unit 35 that drives the plurality of motors 21A and 21B. The motor drive unit 35 is provided on each of a plurality of parallel connection lines 401, 402, 403 and connection lines 401, 402, 403 connecting the power supply 40 side and the ground 41 side, and is arranged on the high voltage side and the low voltage side. A plurality of switching elements 42, 44A, 44B, 43, 45A, 45B and between the switching elements 42, 44A, 44B arranged on the high voltage side and the switching elements 43, 45A, 45B arranged on the low voltage side. A plurality of connection paths 404, 405, 406, and 407 connecting the connection lines are provided. The plurality of motors 21A and 21B are arranged in the plurality of connection paths 404, 405, 406, and 407, respectively. The seatbelt motor drive control device according to the first embodiment can reduce the number of motor drive switching elements for the reason described below. By reducing the number of switching elements, it is possible to provide a motor drive control device having a small and simple configuration.

  In the invention described in Patent Document 1, one H-bridge circuit is required for one motor. That is, at least four switching elements are required for one motor. Since the switching element drives the motor current, it is necessary to use an element having a large current driving capability. An element having a large current driving capability generally requires as many pre-driver circuits as the number of switching elements having a driving capability capable of driving these large elements. Therefore, in the invention described in Patent Document 1, the circuit is increased in size and complexity.

  In the motor drive control device of the present embodiment, a pair of the high side transistor 42 and the low side transistor 43 is used in common among a plurality of motors. The number of switching elements that increase each time the motor is increased is one leg, that is, two switching elements. That is, in the conventional circuit configuration, 4 × N switching elements are required for N motors, but in the circuit configuration according to the present embodiment, 2+ (2 × N) switching elements are provided. Therefore, the number of switching elements used can be reduced as compared with the conventional circuit, and the circuit can be downsized and simplified.

(2) The seatbelt motor drive control device supplies a combined current of the currents flowing through the plurality of motors 21A and 21B to one of the plurality of parallel connection lines 401, 402, and 403. In the present embodiment, the switching element 42 and the switching element 43 can be used in common among a plurality of motors by flowing a combined current of the currents flowing in the motors 21A and 21B through the switching element 42 and the switching element 43. . Therefore, the number of motor driving switching elements can be reduced.

(3) The seatbelt motor drive control device includes a plurality of motors 21A, a combination of two connection lines out of the plurality of parallel connection lines 401, 402, and 403 and switching elements arranged on the two connection lines. A plurality of drive circuits for respectively driving 21B are configured. Rectifying control of a switching element of one driving circuit among a plurality of driving circuits, turning off a switching element of another driving circuit, rectifying control of a switching element of a driving circuit different from one driving circuit, and others The switching element of the driving circuit is switched off. In the present embodiment, for example, the switching elements 42, 43, 44A, and 44B are rectified and controlled, the switching elements 44B and 45B are turned off, and the switching elements 42, 43, 44B, and 45B are rectified and controlled. , 45A can be switched between a state in which current is supplied to the motor 21A and a state in which current is supplied to the motor 21B. Therefore, each motor can be rotated in different rotation directions.

(Second Embodiment)
FIG. 15 is a schematic configuration diagram schematically illustrating a seat belt 20A, 20B, 20C, 20D winding system by the seat belt retractor control device 170 to which the motor drive control device according to the second embodiment is applied. . In the present embodiment, the system is expanded and applied to the seat belts 20C and 20D of the rear seat as compared with the first embodiment. In the present embodiment, the seat belt retractor control device 170 also controls the motors 21C and 21D for winding up the seat belts 20C and 20D in the rear seat.

  FIG. 16 schematically shows an internal configuration of the seat belt retractor control device 170 shown in FIG.

  The seat belt retractor control device 170 includes signals transmitted from the buckle switches 33A, 33B, 33C, 33D provided as electrical contacts in the buckles 24A, 24B, 24C, 24D, various actuators such as the brake stroke sensor 32, or the like. Based on the data transmitted by the CANBUS communication 31, the motor 21A provided in the seat belt retractor 11A is driven as necessary to wind the seat belt 20A. Alternatively, the motor 21B provided on the seat belt retractor 11B is driven to wind the seat belt 20B, or the motor 21C provided to the seat belt retractor 11C is driven to wind the seat belt 20C. The motor 21D provided on the seat belt retractor 11D is driven to wind up the seat belt 20D. The seat belts 20A, 20B, 20C, and 20D may be wound simultaneously.

  The seat belt retractor control device 170 is mainly composed of a motor drive control system LSI 340 and a motor drive circuit 350. The power supply 30 mounted on the vehicle 10 supplies current to the motor drive control system LSI 340 and the motor drive circuit 350. The motor drive control system LSI 340 has a structure in which a microcomputer (hereinafter referred to as “microcomputer”), a peripheral logic circuit, and an H-bridge drive pre-driver are integrated, and controls the motor drive circuit 350. Specifically, after power is supplied to the motor drive circuit 350, the motor drive control system LSI 340 drives the motor drive signals 36, 37, 38A, 39A, 38B, 39B, 38C, 39C, 38D, and 39D. By transmitting to the circuit 350, the rotational drive of the motors 21A, 21B, 21C, and 21D connected to the motor drive circuit 350 is controlled. The motor drive signals 36, 37, 38A, 39A, 38B, 39B, 38C, 39C, 38D, and 39D have a drive capability sufficient to drive the motor drive circuit 350 by a pre-driver in the motor drive control system LSI 340. ing.

  FIG. 17 shows the internal configuration of the motor drive circuit 350 shown in FIG.

  The motor drive signal 36 is the gate of the high side transistor 42, the motor drive signal 37 is the gate of the low side transistor 43, the motor drive signal 38A is the gate of the high side transistor 44A, the motor drive signal 39A is the gate of the low side transistor 45A, and the motor drive signal 38B. Are connected to the gate of the high side transistor 44B, and the motor drive signal 39B is connected to the gate of the low side transistor 45B. The motor drive signal 38C is connected to the gate of the high side transistor 44C, the motor drive signal 39C is connected to the gate of the low side transistor 45C, the motor drive signal 38D is connected to the gate of the high side transistor 44D, and the motor drive signal 39D is connected to the gate of the low side transistor 45D. Has been.

  The high side transistor 42 and the low side transistor 43 are connected in series by a connection line 401 between the power supply 40 and the ground 41. Similarly, the high side transistor 44A and the low side transistor 45A, the high side transistor 44B and the low side transistor 45B, the high side transistor 44C and the low side transistor 45C, and the high side transistor 44D and the low side transistor 45D are connected to the connection lines 402, 403, 410, respectively. 411 is connected in series, and through the connection paths 406, 407, 414, and 415, the negative pole of the motor 21A, the negative pole of the motor 21B, the negative pole of the motor 21C, the negative pole of the motor 21D, Is connected. The positive poles of the motors 21A, 21B, 21C, and 21D are connected to the connection portion of the high-side transistor 42 and the low-side transistor 43 as the same net on the circuit via connection paths 404, 405, 412, and 413, respectively. .

  The high frequency noise absorbing capacitors 46, 47, 190, and 191 are connected between the power supply 40 and the ground 41. The high frequency noise absorbing capacitors 46, 47, 190, and 191 are a set of a high side transistor 44A and a low side transistor 45A, a set of a high side transistor 44B and a low side transistor 45B, a set of a high side transistor 44C and a low side transistor 45C, and a high side transistor. 44D and a set of the low-side transistor 45D are arranged in the immediate vicinity.

  By the motor drive signals 36, 37, 38A, 39A, 38B, 39B, 38C, 39C, 38D, 39D, the high side transistors 42, 44A, 44B, 44C, 44D, the low side transistors 43, 45A, 45B, 45C, 45D By performing ON / OFF, it is possible to control the current flowing through the motor 21A, the motor 21B, the motor 21C, and the motor 21D.

  Other configurations and operations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations as those of the first embodiment, and detailed description thereof is omitted. Also in the motor drive control device according to the second embodiment described above, the number of switching elements can be reduced as in the motor drive control device of the first embodiment. As a result, the cost of the seat belt retractor control device 170 can be reduced.

(Third embodiment)
FIG. 18 is a schematic configuration diagram schematically showing a seat belt 20A and 20B winding system by the seat belt retractor control device 200 to which the motor drive control device according to the third embodiment is applied.

  FIG. 19 is a flowchart showing a processing flow when the reverse rotation request is made to the other motor during normal rotation of one motor in the seat belt retractor control apparatus 200 shown in FIG.

  In the seat belt retractor control device 200, when a reverse rotation request for the other motor is made during normal rotation of one motor and the seat belt control is in the comfort mode, normal rotation and reverse rotation by the duty setting on the reverse rotation side are performed. (This is called “forward / reverse simultaneous control”). Hereinafter, the forward and reverse simultaneous control will be described. If the seat belt control is in the emergency mode, the forward rotation priority control is the same as in the first embodiment.

  FIG. 20 is a schematic diagram showing a current when one motor of the seatbelt retractor control device 200 shown in FIG. 18 is rotating forward and the other motor is rotating backward.

  In FIG. 20, in the forward rotation control of the motor 21A, the same control as in the first embodiment is performed by the current path shown in FIG. In this state, the high-side transistor 42 is turned on, the low-side transistor 45A is controlled to have a positive phase PWM signal, the high-side transistor 44A is controlled to have a reverse phase PWM signal, and the other transistors are turned off. When the reverse rotation control request is received from the motor 21B in the comfort mode, the forward and reverse simultaneous control is performed.

  In the forward and reverse simultaneous control, the high side transistor 42 is switched from on to off, and the high side transistor 44B is switched from off to on. The control by the positive phase PWM signal of the low side transistor 45A and the negative phase PWM signal of the high side transistor 44A is continued. As a result, the current passes through the paths 220, 221, 222, and 223 shown in FIG. 20, and the current can flow in the forward direction for the motor 21A and the reverse direction for the motor 21B.

  As described above, the motor drive control device in the present embodiment performs rectification control using, for example, the high-side transistor 44B, the low-side transistor 45A, and the high-side transistor 44A, and turns off the other transistors. A current is supplied to the motor 21B, and the motors 21A and 21B can be driven simultaneously.

  In the method shown in FIG. 20, both the current flowing in the forward direction of the motor 21A and the current flowing in the reverse direction of the motor 21B are simultaneously controlled by the normal phase PWM of the motor drive signal 39A and the reverse phase PWM of the motor drive signal 38A. . Therefore, the duty of the PWM signal that controls the current of the motor 21A and the PWM signal that controls the current of the motor 21A cannot be set individually. Since the reverse rotation control of the motor 21B is a control that reliably releases the clutch, which is a mechanical component in the seat belt retractor 11B, the duty of the PWM signal in the forward / reverse simultaneous control is matched to the request on the reverse side. In this case, the duty of the motor 21A is larger in the forward / reverse simultaneous control than in the forward rotation control of the motor 21A alone. As a result, for example, the amount of current flowing through the motor 21A becomes larger than in the case of the forward rotation control of the motor 21A alone, and the controllability of the seat belt 20A and the feeling of the occupant PA may change.

  FIG. 21 shows the current when one motor of the seat belt retractor control device 200 shown in FIG. 18 is rotating forward and the other motor is rotating reversely, and the current of the motor that is rotating forward is controlled. It is a schematic diagram. As shown in FIG. 21, the high-side transistor 42 is turned on / off by a PWM signal having a carrier frequency different from the PWM signal controlling the high-side transistor 44A and the low-side transistor 45A. As a result, part of the current flowing through the motor 21B can be regenerated to the power supply 40 side via the path 230. That is, the amount of current flowing through the motors 21A and 21B can be controlled by PWM control of the high-side transistor 42. For example, the amount of current flowing through the motor 21A can be reduced by regenerating a part of the current flowing through the motor 21B to the power supply 40 side.

  After the elapse of the reverse rotation control (several hundred msec) of the motor 21B, the high side transistor 44B is turned off and the high side transistor 42 is turned on to return to the normal rotation control state of the motor 21A alone. By this control, it is possible to control the seat belts 20A and 20B that are less uncomfortable for the passenger PA and the passenger PB than in the first embodiment. The same applies to the forward / reverse simultaneous control when the motor 21A is requested to reverse during the normal rotation of the motor 21B.

  Other configurations and operations are the same as those of the first embodiment, and the same configurations as those of the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted.

According to the present embodiment described above, the following operational effects can be obtained in addition to the operational effects similar to those of the first and second embodiments.
(4) The motor drive control device includes a plurality of motors 20A and 20B and a motor drive unit 35 that drives the plurality of motors 20A and 20B. The motor drive unit 35 is provided on each of a plurality of parallel connection lines 401, 402, 403 and connection lines 401, 402, 403 connecting the power supply 40 side and the ground 41 side, and is arranged on the high voltage side and the low voltage side. A plurality of switching elements 42, 44A, 44B, 43, 45A, 45B and between the switching elements 42, 44A, 44B arranged on the high voltage side and the switching elements 43, 45A, 45B arranged on the low voltage side. A plurality of connection paths 404, 405, 406, and 407 connecting the connection lines are provided. The plurality of motors 21A and 21B are arranged in a plurality of connection paths 404, 405, 406, and 407, respectively, and rectify and control switching elements of two connection lines among the plurality of parallel connection lines 401, 402, and 403, The switching elements of the other connection lines are turned off, and some of the plurality of motors are driven. In the present embodiment, for example, rectification control is performed using switching elements 44A, 45A, 44B, and 45B, and other transistors are turned off to supply current to motor 21A and motor 21B. Can be driven.

(5) The motor drive control device performs switching control of some of the switching elements of the other connection lines, and individually controls currents flowing to some of the plurality of motors. In the present embodiment, rectification control is performed using the switching elements 44A, 45A, 44B, and 45B, and the switching element 42 is a PWM signal having a carrier frequency different from the PWM signal that controls the switching element 44A and the switching element 45A. To turn it on and off. Therefore, the amount of current flowing through the motor 21A can be individually controlled.

  The present invention is not limited to the first to third embodiments described above, and includes various modifications. For example, the first to third embodiments described above have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. It is possible to add, delete, and replace other configurations for a part of the configurations of the first to third embodiments.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by the processor interpreting and executing a program that realizes each function. Information such as programs, tables, and files that realize each function can be stored in a storage device such as a memory, a hard disk, or an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.

  The control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

DESCRIPTION OF SYMBOLS 10 Vehicle 11A, 11B, 11C, 11D Seat belt retractor 12 Obstacle sensor 14 Wheel speed sensor 16 Collision judgment controller 18 Brake assist device 20A, 20B, 20C, 20D Seat belt 21A, 21B, 21C, 21D Motor 15, 170, 200 Seat belt retractor control device 24A, 24B, 24C, 24D Buckle 30 Power supply 31 mounted on vehicle 31 CAN bus 32 Brake stroke sensor 33A, 33B, 33C, 33D Buckle switch 34, 340 System LSI for controlling seat belt retractor
35, 350 Motor drive circuit 36, 38A, 38B, 38C, 38D High side transistor control motor drive signal 37, 39A, 39B, 39C, 39D Low side transistor control motor drive signal 40 Motor drive circuit power supply 41 Motor drive circuit ground 42 44A, 44B, 44C, 44D High-side transistors 43, 45A, 45B, 45C, 45D Low-side transistors 46, 47, 190, 191 High-frequency noise absorbing capacitors 51, 54 Motor drive current paths 53, 56 during normal rotation Circulation current paths 52, 55 Motor drive current consumption paths 71, 74 during forward rotation Motor drive current paths 72, 75 during reverse rotation Motor drive consumption current paths 73, 76 during reverse rotation Circulation current paths 101, 102, 103 during reverse rotation Control or forward rotation priority control Current paths 111, 112, 113 flowing in the forward rotation side motor in the current rotation path 220, 221 flowing in the reverse rotation side motor in the forward rotation temporary stop control or forward rotation priority control In the forward rotation reverse rotation simultaneous control, Current path 222 Flowing current path 223 in forward and reverse simultaneous control Motor drive current consumption path 230 in forward and reverse simultaneous control Forward current adjustment current path PA, PB, PC, PD in forward and reverse simultaneous control , 403, 410, 411 Connection line 404, 405, 406, 407, 412, 413, 414, 415 Connection path

Claims (7)

In a seat belt motor drive control device comprising: a plurality of motors that wind up a plurality of seat belts; and a motor drive unit that drives the plurality of motors.
The motor drive unit is
A plurality of parallel connection lines connecting the power supply side and the ground side;
A plurality of switching elements provided on each of the connection lines and disposed on a high-pressure side and a low-pressure side;
A plurality of connection paths connecting the connection lines between the switching element disposed on the high voltage side and the switching element disposed on the low voltage side;
The plurality of motors are seat belt motor drive control devices arranged in the plurality of connection paths, respectively. In the seatbelt motor drive control device according to claim 1,
A seatbelt motor drive control device for supplying a combined current of currents flowing through the plurality of motors to one of the plurality of parallel connection lines. In the seatbelt motor drive control device according to claim 1,
A plurality of drive circuits that respectively drive the plurality of motors are configured by two connection lines of the plurality of parallel connection lines and the switching elements disposed on the two connection lines.
A state in which the switching element of one of the plurality of drive circuits is rectified and controlled, and the switching element of another drive circuit is turned off, and the switching element of a drive circuit different from the one drive circuit is A seat belt motor drive control device that performs rectification control and switches a state in which the switching element of another drive circuit is turned off. In a motor drive control device comprising a plurality of motors and a motor drive unit that drives the plurality of motors,
The motor drive unit is
A plurality of parallel connection lines connecting the power supply side and the ground side;
A plurality of switching elements provided on each of the connection lines and disposed on a high-pressure side and a low-pressure side;
A plurality of connection paths connecting the connection lines between the switching element disposed on the high voltage side and the switching element disposed on the low voltage side;
The plurality of motors are respectively disposed in the plurality of connection paths,
Rectification control is performed on the switching elements of two of the plurality of parallel connection lines, and the switching elements of the other connection lines are turned off to drive some of the plurality of motors. Motor drive control device. In the motor drive control device according to claim 4,
A motor drive control device that performs switching control of a part of the switching elements of the other connection lines and individually controls a current flowing to a part of the plurality of motors. In the motor drive control device according to claim 4 or 5,
The plurality of motors are motor drive control devices that are motors provided in a seat belt retractor device for winding and withdrawing the seat belt. In a motor drive control device comprising a plurality of motors and a motor drive unit that drives the plurality of motors,
The motor drive unit is
A plurality of parallel connection lines connecting the power supply side and the ground side;
A plurality of switching elements arranged on the connection line;
A plurality of connection paths in which the number of the connection lines connecting the switching elements of the connection lines is less than the number of the connection lines;
The plurality of motors are respectively disposed in the plurality of connection paths,
A plurality of drive circuits for driving the motor are constituted by two connection lines of the plurality of parallel connection lines and the switching elements arranged on the two connection lines,
A state in which the switching element of one of the plurality of drive circuits is rectified and controlled, and the switching element of another drive circuit is turned off, and the switching element of a drive circuit different from the one drive circuit is A motor drive control device that performs rectification control and switches a state in which the switching element of another drive circuit is turned off.

Images