JP2006082681A - Transmission ratio variable device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission ratio variable device capable of enhancing the steering feeling. <P>SOLUTION: When the vehicle speed is no higher than 10 km/h according to a vehicle speed signal given by a vehicle speed sensor (Yes at S107), an IFS_ECU of a vehicle control device performs a process involving a rotational drive of a motor of a transmission ratio variable mechanism in the initializing process planned to be conducted immediately after the vehicle engine is started, for example a lock releasing process (S111) or a false insertion confirming process (S113). When the vehicle speed exceeds 10 km/h (No at S107), therefore, the system will not performs the process involving the rotational drive of the motor of the transmission ratio variable mechanism in the initializing process, so that it is possible to prevent the motor from being driven into rotation owing to the initializing process when the vehicle is running at a speed exceeding 10 km/h. Accordingly the sense of incongruity of the driver in steering can be precluded, which is likely to appear remarkably in running, for example with as high a speed as 80 km/h, and the steering feeling can be enhanced. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transmission ratio variable device including a transmission ratio variable mechanism provided in the middle of a steering transmission system of a vehicle.

  A transmission ratio variable mechanism that is provided in the middle of the steering transmission system of the vehicle that connects the steering wheel and the steering wheel, and that can change the transmission ratio between the input shaft on the steering wheel side and the output shaft on the steering wheel side by rotating the electric motor. For example, there is a “vehicle steering control device” disclosed in Patent Document 1 below. Such a transmission ratio variable device is used, for example, in the vehicle control device 100 shown in FIG. Here, the configuration of the vehicle control device 100 will be described with reference to FIG. In addition, the vehicle control apparatus provided with such a transmission ratio variable device may be called IFS (Intelligent Front Steering system; “IFS” is a registered trademark of Toyota Koki Co., Ltd.).

  As shown in FIG. 1, the vehicle control apparatus 100 includes a steering wheel (handle) 21, a first steering shaft (input shaft) 22, a second steering shaft (output shaft) 23, an EPS actuator 24, a rod 25, a steering angle sensor. 26, vehicle speed sensor 27, torque sensor 28, IGSW sensor 29, lock mechanism 30, transmission ratio variable mechanism 40, IFS_ECU 50, EPS_ECU 60, and the like. The ECU (Electronic Control Unit) is an electronic control device.

  Specifically, one end of the first steering shaft 22 is connected to the steering wheel 21, and the input side of the transmission ratio variable mechanism 40 is connected to the other end side of the first steering shaft 22 via the lock mechanism 30. The transmission ratio variable mechanism 40 includes a motor, a speed reducer, and the like. For example, the transmission ratio variable mechanism (100) including the motor (110) and the speed reducer (120) disclosed in Patent Document 1 is provided. It corresponds to. One end side of the second steering shaft 23 is connected to the output side of the transmission ratio variable mechanism 40, and the input side of the EPS actuator 24 is connected to the other end side of the second steering shaft 23. The lock mechanism 30 is a mechanism that can prevent the motor of the transmission ratio variable mechanism 40 from rotating. For example, the lock holder (141), the lock arm (150), the electromagnetic coil (154), etc. disclosed in Patent Document 1. The lock mechanism (130) consisting of this corresponds to this. The numbers in parentheses correspond to the symbols described in the following Patent Document 1 (the same applies to [Background Art] and [Problems to be Solved by the Invention]).

  The EPS actuator 24 is an electric power steering device, and can convert the rotational motion input by the second steering shaft 23 into the axial motion of the rod 25 by a rack and pinion gear or the like (not shown) and output the EPS_ECU 60. The assist motor controlled by the controller generates an assist force according to the steering state so that the driver can assist the steering. The rod 25 is equipped with steering wheels FR and FL.

  The rotation angle (steering angle) of the first steering shaft 22 is detected by the steering angle sensor 26 and is detected as a steering angle signal by the IFS_ECU 50, and the steering torque by the second steering shaft 23 is detected by the torque sensor 28 and is detected as a torque signal. The EPS_ECU 60 is configured to be able to input each. Further, the vehicle speed is detected by a vehicle speed sensor 27 via a CAN (Controller Area Network) 90, and on / off information of an ignition switch (hereinafter referred to as “IGSW”) is received by an IGSW sensor 29. It is configured to be detected and input to the IFS_ECU 50 and the EPS_ECU 60 as IG signals, respectively.

  With this configuration, in the transmission ratio variable mechanism 40 and the IFS_ECU 50, the transmission ratio of the second steering shaft 23 to the first steering shaft 22 (hereinafter referred to as “steering transmission ratio”) is set to the vehicle speed by the motor and the reduction gear. Accordingly, the ratio is changed in real time, and the ratio of the output angle of the second steering shaft 23 to the steering angle of the first steering shaft 22 is varied. Further, in the EPS actuator 24 and the EPS_ECU 60, an assist force that assists the driver's steering is generated by the assist motor in accordance with the driver's steering state and vehicle speed detected by the torque sensor 28 and the vehicle speed sensor 27.

  Thereby, the steering transmission ratio corresponding to the vehicle speed, for example, when the vehicle is stopped or traveling at low speed, the output angle to the second steering shaft 23 by the transmission ratio variable mechanism 40 is set to be larger than the steering angle of the steering wheel 21; In addition, when the vehicle is traveling at high speed, the output angle of the transmission ratio variable mechanism 40 can be set to be smaller than the steering angle of the steering wheel 21, while an appropriate assist force corresponding to the vehicle speed is generated by the assist motor. It becomes possible to make it.

  By the way, the IFS_ECU 50 and EPS_ECU 60 described above are electronic control devices composed of a memory device, an input / output interface, and the like centering on a microprocessor, but these usually trigger an ON signal of the IGSW detected by the IGSW sensor 29. Thus, after performing a predetermined initialization process, it is programmed to perform each control as described above.

  For example, in the “vehicle steering control device” disclosed in Patent Document 1, the lock release control (S200) is performed as a predetermined initialization process immediately after being activated by turning on the IGSW, and the lock mechanism (130) is used. It is configured to perform transmission ratio variable control (S102 to S112) after unlocking the motor (110) (Patent Document 1; paragraph number 0030, FIG. 5).

However, there is a case where the lock of the motor (110) is not released normally because the lock holder (140) and the lock arm (150) constituting the lock mechanism (130) are not engaged with each other due to the engagement. Can do. For this reason, in the disclosed technology disclosed in Patent Document 1, the lock holder (140) and the lock arm (150) are engaged by reciprocating the motor (110) in a predetermined range in the unlocking control (S200). Such a problem is solved by checking the unlocking by rotating the motor (110) within a range that can be rotated if unlocked or unlocking (Patent Document 1; paragraph) Numbers 0033-0036, FIG. 6).
JP 2001-48032 A (2nd to 6th pages, FIGS. 3 to 6)

  However, according to such a vehicle control device 100, the IFS_ECU 50 and the EPS_ECU 60 acquire the IGSW ON signal from the IGSW sensor 29 via the CAN 90. Therefore, depending on the traffic state of the CAN 90, the information of the IGSW sensor 29 is processed even if the IGSW ON signal arrives at the IFS_ECU 50 or the like after the IGSW is actually turned on, or even if the CAN 90 traffic is not crowded When the ECU is performing heavy load processing, the processing speed of the IGSW on signal is slowed down, and therefore the IGSW on signal may reach the IFS_ECU 50 or the like after the IGSW is actually turned on.

  That is, even if the IGSW ON signal is configured to reach the IFS_ECU 50 or the like in real time from the IGSW sensor 29, the IGSW ON signal is not necessarily input to the IFS_ECU 50 or the like immediately after the IGSW is turned on. In some cases, it may arrive a few seconds later. Therefore, when the ON signal of the IGSW is input with a delay from the actual ON of the IGSW in this way, as disclosed in Patent Document 1, a predetermined initialization is triggered by the input of the ON signal of the IGSW. If the unlocking control (S200) is performed as a process, the motor (110) may be reciprocally oscillated within a predetermined range or unlocked even though the vehicle is running. In this case, the motor (110) is rotated within a range where it can rotate.

  In addition, since the IGSW ON signal is acquired via the CAN 90, even after the IGSW is actually turned ON due to a transmission error caused by external noise or the like, the IGSW ON signal is again displayed. It may be input. Even in such a case, when the unlocking control (S200) is performed as a predetermined initialization process triggered by the IGSW ON signal input in error, the vehicle is traveling. The motor (110) is reciprocally oscillated within a predetermined range, or if the lock is released, the motor (110) is rotated within a range that can be rotated.

  Therefore, since the unexpected rotation of the motor (110) of the transmission ratio variable mechanism (100) such as these may be transmitted to the steering wheel 21 via the first steering shaft 22, it depends on the traveling speed of the vehicle. This causes a technical problem that the driver who is steering can give a sense of incongruity to steering.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a transmission ratio variable device capable of improving the steering feeling.

  In order to achieve the above object, in the transmission ratio variable device according to claim 1 described in the claims, the steering transmission system [22, 23] of the vehicle connecting the steering wheel [21] and the steering wheels [FR, FL]. , 24, 25], the transmission ratio between the input shaft [22] on the steering wheel side and the output shaft [23] on the steering wheel side can be changed by the rotational drive of the electric motor [40m]. A variable ratio mechanism [40], motor control means [50] capable of controlling the rotational drive of the electric motor [40m], and vehicle speed information acquisition means [27] capable of acquiring information [V] relating to the speed of the vehicle; The motor control means [50] is configured such that the speed of the vehicle is a predetermined speed based on the information [V] related to the speed by the vehicle speed information acquisition means [27]. In the following cases, [S107 Yes], and techniques characterized in that those with the rotation of the electric motor [40 m] in the initialization process will take place immediately after the engine start of the vehicle. The numbers in [] can correspond to the symbols described in the [Best Mode for Carrying Out the Invention] column (the same applies hereinafter).

  In the transmission ratio variable device according to claim 2, the transmission ratio between the input shaft [22] and the output shaft [23] is prevented by preventing the electric motor [40m] from being rotationally driven. The transmission ratio variable device [20] according to claim 1, further comprising a lock mechanism [30] capable of setting the ratio to 1: 1, wherein the initialization process involves rotational driving of the electric motor [40m]. Is technically characterized in that the electric motor [40m] is rotationally driven to ensure the release of the lock mechanism [30] [S111].

  Further, in the transmission ratio variable device according to claim 3, the transmission ratio between the input shaft [22] and the output shaft [23] is prevented by preventing the electric motor [40m] from being rotationally driven. The transmission ratio variable device [20] according to claim 1, further comprising a lock mechanism [30] capable of setting the ratio to 1: 1, wherein the initialization process involves rotational driving of the electric motor [40m]. The technical feature is that the electric motor [40m] is rotated to inspect the operation or non-operation of the lock mechanism [30] [S113].

  In the first aspect of the invention, the motor control means [50], when the speed of the vehicle is equal to or lower than the predetermined speed based on the information [V] related to the speed by the vehicle speed information acquisition means [27] [S107; Yes], Since the initialization process scheduled to be performed immediately after the engine is started is accompanied by the rotational drive of the electric motor [40 m], when the speed of the vehicle exceeds a predetermined speed [S107; No], the initialization process Therefore, the electric motor [40 m] is not accompanied by rotational driving. Thus, at a speed exceeding the predetermined speed, the initialization process is not performed with the rotational drive of the electric motor [40 m]. It is possible to prevent the electric motor [40m] of the variable ratio mechanism [40] from being rotationally driven. Therefore, it is possible to prevent the driver from feeling uncomfortable when the vehicle is traveling at high speed, thereby improving the steering feeling.

  In the second aspect of the invention, in the initialization process according to the first aspect, the rotation drive of the electric motor [40m] is caused to rotate the electric motor [40m] to prevent the rotation drive of the electric motor [40m]. Thus, the release of the lock mechanism [30] that can set the transmission ratio of the input shaft [22] and the output shaft [23] to 1: 1 is ensured [S111]. Thus, at a speed exceeding the predetermined speed, the control [S111] for reliably releasing the lock mechanism [30] by rotating the electric motor [40m] in the initialization process is not performed. It is possible to prevent the electric motor [40m] of the transmission ratio variable mechanism [40] from being rotationally driven by the initialization process when traveling at a high speed exceeding the speed. Therefore, it is possible to prevent the driver from feeling uncomfortable when the vehicle is traveling at high speed, thereby improving the steering feeling.

  In the third aspect of the invention, the initialization process of the first aspect involving the rotational drive of the electric motor [40m] prevents the rotational drive of the electric motor [40m] by rotating the electric motor [40m]. Then, the operation or non-operation of the lock mechanism [30] capable of setting the transmission ratio between the input shaft [22] and the output shaft [23] to 1: 1 is checked [S113]. Accordingly, at a speed exceeding the predetermined speed, the control [S113] for inspecting the operation or non-operation of the lock mechanism [30] by rotating the electric motor [40m] in the initialization process is not performed. For example, it is possible to prevent the electric motor [40m] of the transmission ratio variable mechanism [40] from being rotationally driven by the initialization process when traveling at a high speed exceeding a predetermined speed. Therefore, it is possible to prevent the driver from feeling uncomfortable when the vehicle is traveling at high speed, thereby improving the steering feeling.

  Hereinafter, an embodiment in which a transmission ratio variable device of the present invention is applied to a vehicle control device will be described with reference to FIGS. The vehicle control device 20 according to the present embodiment is not different from the vehicle control device 100 described above in mechanical structure, and will be described with reference to the vehicle control device 20 (100) shown in FIG.

  As shown in FIG. 1, the vehicle control device 20 includes a steering wheel 21, a first steering shaft 22, a second steering shaft 23, an EPS actuator 24, a rod 25, a steering angle sensor 26, a vehicle speed sensor 27, a torque sensor 28, an IGSW. The sensor 29, the lock mechanism 30, the transmission ratio variable mechanism 40, the IFS_ECU 50, the EPS_ECU 60, the CAN 90, and the like are configured as described above. Therefore, these descriptions are omitted here. 2 is a functional block diagram showing vehicle control processing by the IFS_ECU 50 and the EPS_ECU 60 of the vehicle control device 20 according to the present embodiment. Here, the vehicle by these two ECUs of the vehicle control device 20 is shown. An outline of the control process will be briefly described.

  As shown in FIG. 2, in the vehicle control device 20 according to the present embodiment, an IFS control process 50 a is performed by the IFS_ECU 50, and an EPS control process 60 a is performed by the EPS_ECU 60.

  Specifically, the IFS control processing 50a is a transmission ratio that is uniquely determined corresponding to the vehicle speed by inputting the steering angle signal θh from the steering angle sensor 26 and the vehicle speed signal V from the vehicle speed sensor 27 to the IFS_ECU 50. A process of determining the rotation angle of the motor 40m of the variable mechanism 40 from a motor rotation angle map (not shown) is performed, and a motor voltage corresponding to the determined rotation angle command value is supplied to the motor 40m by the motor drive circuit. The rotation angle θvm of the motor 40m is detected by the rotation angle sensor 40s and input to the IFS_ECU 50. Thereby, in the transmission ratio variable mechanism 40 and the IFS_ECU 50, the ratio of the output gear to the input gear, that is, the steering transmission ratio is changed in real time according to the vehicle speed by the motor 40m and the reduction gear 40g, and the steering angle of the first steering shaft 22 is changed. The ratio of the output angle of the second steering shaft 23 is variable.

  Further, the EPS control processing 60a includes an assist motor for the EPS actuator 24 that is uniquely determined according to the vehicle speed by inputting the steering torque signal Tp from the torque sensor 28 and the vehicle speed signal V from the vehicle speed sensor 27 to the EPS_ECU 60. A process of determining a current command value of 24 m from a motor current map (not shown) is performed, and a motor voltage corresponding to the determined current command value is supplied to the assist motor 24 m by the motor drive circuit. The rotation angle θpm of the assist motor 24m is detected by the rotation angle sensor 24s and input to the EPS_ECU 60. As a result, the EPS actuator 24 and the EPS_ECU 60 use the EPS control process 60a to generate assist force for assisting the driver's steering according to the driver's steering state and vehicle speed detected by the torque sensor 28 and the vehicle speed sensor 27. It is generated by.

  Since the IFS_ECU 50 and the EPS_ECU 60 receive the IGSW ON signal and the OFF signal output from the IGSW sensor 29, the IFS_ECU 50 and the EPS_ECU 60 start the respective control processes triggered by the input of the IGSW ON signal. In addition, each control process can be terminated with the input of the IGSW off signal as a trigger.

  Thereby, in the vehicle control device 20, the transmission ratio variable mechanism 40 can be variably controlled according to the speed of the vehicle by the IFS control process 50a by the IFS_ECU 50, and the EPS control process 60a by the EPS_ECU 60 is adapted to the steering state. The assist force can be generated to assist steering by the driver.

  Here, since the lock mechanism 30 that can prevent the rotation drive of the motor 40m of the transmission ratio variable mechanism 40 controlled in this way is shown in FIG. 3, the configuration and operation of the lock mechanism 30 are based on FIG. explain.

  As shown in FIG. 3, the lock mechanism 30 mainly includes a housing 31, a lock holder 32, a lock arm 33, a support shaft 34, a solenoid 35, and the like below (on the second steering shaft 23 side). A transmission ratio variable mechanism 40 provided with a motor 40m is located. The configuration of the transmission ratio variable mechanism 40 is publicly known and is disclosed in detail in the above-described Patent Document 1 (Japanese Patent Laid-Open No. 2001-48032; paragraph numbers 0018 to 0021), and thus the description thereof is omitted here. .

  The housing 31 has a function of accommodating the lock holder 32, the lock arm 33, the solenoid 35, and the like constituting the lock mechanism 30 therein. The housing 31 is configured so that the housing of the transmission ratio variable mechanism 40 can be attached below (on the second steering shaft 23 side), so that the transmission ratio variable mechanism connected to the housing 40a of the transmission ratio variable mechanism 40 is configured. 40, that is, the second steering shaft 23 and the housing 31 can be fixedly connected.

  The lock holder 32 is attached and fixed over the entire outer periphery of the first steering shaft 22 that passes through the lock mechanism 30 and is connected to the input side of the transmission ratio variable mechanism 40, and the outer periphery thereof is provided at predetermined intervals in the circumferential direction. An engaging recess 32a extending in the axial direction is formed. Only the lock holder 32 is configured to be able to freely rotate according to the rotation of the first steering shaft 22.

  The lock arm 33 is formed with an engagement convex portion 33a that can be engaged with the engagement concave portion 32a at one end of the lock arm 33, and is formed in a “shape” toward the other end. A shaft hole through which the support shaft 34 can pass is formed in the bent portion. Further, the other end of the lock arm 33 constitutes a connecting end 33b that can connect the tip of the plunger 35b of the solenoid 35.

  The support shaft 34 has a shaft diameter that can be supported by penetrating the shaft hole of the lock arm 33. When the lock arm 33 supported by the support shaft 34 rotates about the shaft, the lock arm One end of the support shaft 34 is fixed to the housing 31 so that the engagement protrusion 33 a of 33 can engage with the engagement recess 32 a of the lock holder 32. A torsion coil spring 36 is also attached to the support shaft 34, and the torsion coil spring 36 is engaged with the lock holder 32 by the engaging projection 33 a of the lock arm 33 supported by the support shaft 34. The lock arm 33 is urged in a direction to engage with the recess 32a.

  The solenoid 35 includes an electromagnetic coil 35a wound around a fixed iron core and a plunger 35b which is a movable iron core. When an excitation current is supplied to the electromagnetic coil 35a via the input / output pin 38, the plunger 35b is moved. It has a function of performing electromagnetic attraction in the direction of the electromagnetic coil 35a. The distal end of the plunger 35 b is configured to be connectable to the connecting end 33 b of the lock arm 33. For this reason, the coupling end 33b of the lock arm 33 pivotally supported by the support shaft 34 is coupled to the plunger 35b, so that when the exciting current is supplied to the solenoid 35, the force that pulls the lock arm 33 toward the solenoid 35. Will act on the lock arm 33. The presence / absence of the excitation current supplied via the input / output pin 38 is controlled by an IFS control process 50a (see FIG. 4) described later by the IFS_ECU 50.

  The lock mechanism 30 configured as described above has a lock arm 33 rotatably supported on the support shaft 34, and the engagement convex portion 33 a of the lock arm 33 is engaged with the engagement concave portion of the lock holder 32. It is urged by the urging force of the torsion coil spring 36 in the direction in which it engages with 32a. For this reason, when the exciting current is not supplied to the solenoid 35 by the control of the IFS_ECU 50, the engagement convex portion 33a of the lock arm 33 is engaged with the engagement concave portion 32a of the lock holder 32, and the lock holder 32 is rotated. Since the state locked in the direction is maintained, rotation of the lock holder 32 is prevented. As a result, the first steering shaft 22 attached and fixed to the lock holder 32, the second steering shaft 23 fixedly connected to the housing 31 via the housing 40a of the transmission ratio variable mechanism 40, Are engaged with each other, and the two are coupled at a transmission ratio of 1: 1. That is, the first steering shaft 22 that is an input shaft and the second steering shaft 23 that is an output shaft can be coupled at a transmission ratio of 1: 1.

  On the other hand, when the exciting current is supplied to the solenoid 35 by the control of the IFS_ECU 50, the lock arm 33 is pulled toward the solenoid 35 against the urging force of the torsion coil spring 36. Therefore, since the engagement convex portion 33a of the lock arm 33 rotates in a direction to disengage from the engagement concave portion 32a of the lock holder 32 around the support shaft 34, the lock holder 32 is unlocked by the lock arm 33, The rotation prevention of the lock holder 32 is released. As a result, the first steering shaft 22 fixed to the lock holder 32 can be rotated without being locked to the second steering shaft 23 connected to the housing 31. That is, the first steering shaft 22 that is an input shaft and the second steering shaft 23 that is an output shaft can be connected at a transmission ratio n: m (n and m are positive numerical values excluding 0).

  Next, the flow of the IFS control process 50a including the initialization process of the lock mechanism 30 will be described based on the flowchart shown in FIG. Note that steps S103 to S113 can correspond to “initialization processing scheduled to be performed immediately after starting the vehicle engine” described in the claims, and step S111 and step S113 of those steps are within the scope of the claims. This may correspond to the description “with motor rotational drive”. Further, step S111 corresponds to “thing that ensures the operation or non-operation of the lock mechanism” described in the claims, and step S113 includes “operation or non-operation of the lock mechanism described in the claims”. It can correspond to “what to inspect”.

  As shown in FIG. 4, the IFS control process 50a is activated by the input of an IGSW ON signal as a trigger (S101: Yes). Then, in step S103, initialization processing of hardware around the microprocessor such as the memory device, the input / output interface, the A / D converter, and the D / A converter is performed, and then whether or not the IFS control is abnormal in step S105. Judgment processing is performed.

  In this step S105, for example, whether or not the power supply voltage value supplied to the IFS_ECU 50 is in a normal range, whether or not there is an abnormality in the result of the initialization processing of the hardware such as the memory device in step S103, and Judgment is made as to whether or not the vehicle engine is started, and all the determination conditions are satisfied, that is, the power supply voltage value is in a normal range, the hardware initialization processing result is normal, and the engine If it has been started (S105: Yes), the process proceeds to the next step S107.

  If the determination condition is not satisfied in step S105 (S105: No), the determination process in step S105 is repeated a predetermined number of times (for example, five times). If the determination condition is not satisfied even within the number of times, for example, the vehicle The alarm display is output to the instrument panel (not shown).

  In a succeeding step S107, it is determined whether or not the traveling speed of the vehicle is equal to or lower than a predetermined speed. As described above, since the IFS_ECU 50 acquires the vehicle speed signal V from the vehicle speed sensor 27 via the CAN 90, the IFS_ECU 50 determines the speed of the vehicle based on the vehicle speed signal V. For example, when the speed is 10 km or less (S107) : Yes), the process proceeds to the next step S109, and if the speed is not less than 10 km / h (S107: No), the process flow is set so that this step S107 is executed again. That is, when the vehicle speed immediately after the engine start of the vehicle exceeds 10 km / h (S107: No), the process waits until the speed becomes 10 km or less (S107: Yes).

  Thus, until the vehicle speed becomes 10 km / h or less (S107: Yes), the unlocking process in the subsequent step S109 is not performed, and therefore the exciting current is supplied to the electromagnetic coil 35a of the locking mechanism 30 described above. Since the lock holder 32 and the lock arm 33 maintain the engaged state, the first steering shaft 22 and the second steering shaft 23 remain connected at a transmission ratio of 1: 1. In this way, it is rare that the vehicle speed immediately after starting the engine exceeds 10 km / h. However, for example, when the driver depresses the axle pedal immediately after turning on the IGSW, the vehicle speed increases immediately after the engine starts. When the vehicle accelerates, the process waits until the vehicle speed becomes 10 km or less in step S107. During that time, the IFS does not function and the steering transmission ratio is set to 1: 1.

  Similarly, until the vehicle speed becomes 10 km / h or less (S107: Yes), the unlocking process in step S111 and the insertion abnormality confirmation process in step S113 are not performed. Thus, the motor 40m of the transmission ratio variable mechanism 40 is not rotationally driven. Therefore, even if the vehicle speed exceeds 10 km per hour due to the rapid acceleration after turning on the IGSW as described above, the initialization process with the rotational drive of the motor 40 m is not performed during this time, and the rotational drive of the motor 40 m is prevented. It is possible to prevent the driver of the vehicle from feeling uncomfortable with steering due to vibrations transmitted to the steering wheel 21 via the first steering shaft 22.

  In the next step S109, the lock mechanism 30 is unlocked. That is, when the vehicle speed is 10 km / h or less (S107: Yes), as described above, an exciting current is supplied to the electromagnetic coil 35a via the input / output pin 38 of the lock mechanism 30. Then, since an electromagnetic attractive force is generated in the electromagnetic coil 35a, the plunger 35b is attracted in the direction of the electromagnetic coil 35a, and the engaging convex portion 33a of the lock arm 33 that has been engaged with the engaging concave portion 32a of the lock holder 32 until then. Is disengaged from the engagement recess 32a and the engagement between the two is released. As a result, the lock holder 32 blocked by the lock arm 33 can be rotated, so that the second steering shaft 23 connected to the first steering shaft 22 can be freely rotated at a transmission ratio of 1: 1. Become. That is, the function of IFS becomes possible.

  In the subsequent step S111, unlocking processing is performed. In this process, the engagement concave portion 32a of the lock holder 32 and the engagement convex portion 33a of the lock arm 33 constituting the lock mechanism 30 are engaged with each other. This is for coping with the case where the lock of the motor 40m of the transmission ratio variable mechanism 40 is not normally released, and the lock mechanism 30 is reliably released. Specifically, the engagement between the lock holder 32 and the lock arm 33 is released by reciprocating vibrationally within a range where the recess of the engagement recess 32a is formed. This process is publicly known and is disclosed in detail in the above-mentioned Patent Document 1 (Japanese Patent Laid-Open No. 2001-48032; Paragraph Nos. 0033 to 0036).

  In the next step S113, an insertion abnormality confirmation process is performed. This processing is performed when the lock mechanism 30 functions to lock the first steering shaft 22 and the second steering shaft 23 and to connect them with a transmission ratio of 1: 1. This is for checking whether or not the lock mechanism 30 is activated or deactivated. Specifically, the engagement convex portion 33a of the lock arm 33 is inserted into the engagement concave portion 32a of the lock holder 32 by reciprocating in a range wider than the range where the concave portion of the engagement concave portion 32a is formed. Is engaged, it is confirmed that it is normally inserted (engaged) using the accumulated error of the detected position with respect to the rotation control target value. This process may be disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2001-48032; paragraph numbers 0051 to 0053) described above.

  When the series of initialization processes in steps S103 to S113 is completed in this way, a normal process of IFS is performed in step S115. This process allows the steering transmission ratio to be variably controlled according to the speed of the vehicle by the transmission ratio variable mechanism 40, and since it has already been described with reference to FIG. 2, it is omitted here. The normal processing of IFS in step S115 is continuously continued until the IGSW OFF signal is input from the vehicle speed sensor 27 via the CAN 90 (S117: Yes).

  As described above, according to the vehicle control device 20 according to the present embodiment, the IFS_ECU 50 determines that the vehicle when the vehicle speed is 10 km / h or less based on the vehicle speed signal V from the vehicle speed sensor 27 (S107: Yes). The initializing process scheduled to be performed immediately after starting the engine is accompanied by rotational driving of the motor 40m of the transmission ratio variable mechanism 40, for example, the unlocking process (S111) and the insertion abnormality confirmation process (S113). When the speed of the vehicle exceeds 10 km / h (S107: No), the initialization process does not involve the rotational drive of the motor 40m of the transmission ratio variable mechanism 40. Thus, at a speed exceeding 10 km / h, the initialization process does not involve rotation of the motor 40m of the transmission ratio variable mechanism 40. For example, when traveling at a speed exceeding 10km / h It is possible to prevent the motor 40m of the transmission ratio variable mechanism 40 from being rotated by the initialization process. Therefore, since the unexpected rotation of the motor 40m such as these is not transmitted to the steering wheel 21 via the first steering shaft 22, for example, a driver who tends to appear remarkably when traveling at a high speed of 80 km / h, for example. The steering feeling can be improved by preventing the uncomfortable feeling of steering.

  In the above-described embodiment, 10 km / h is set as the “predetermined speed”. However, the present invention is not limited to this as long as the vehicle speed is unlikely to give an uncomfortable feeling to the driver's steering. It may be set to 15 km / h or 20 km / h.

  In the above-described embodiment, the unlocking process in step S111 and the insertion abnormality confirmation process in step S113 are exemplified and described as “with motor rotation driving”, but the present invention is not limited to this, and the motor is not limited thereto. If it is accompanied by rotational drive, for example, in order to confirm the normality of the semiconductor switching element (MOSFET or the like) that drives the motor (motor 40m) (there is no short circuit or open in the element) For example, processing for outputting a predetermined switching signal (duty waveform) may be used. In this case as well, the same operations and effects as described above can be obtained.

It is explanatory drawing which shows the structure outline | summary of a vehicle control apparatus. It is a functional block diagram showing the vehicle control process by IFS_ECU and EPS_ECU of the vehicle control apparatus which concerns on this embodiment. It is a perspective view which shows the locking mechanism of the vehicle control apparatus which concerns on this embodiment. It is a flowchart which shows the flow of the IFS control process by IFS_ECU of the vehicle control apparatus which concerns on this embodiment.

Explanation of symbols

20 ... Vehicle control device 21 ... Steering wheel (handle)
22 ... 1st steering shaft (steering transmission system, input shaft)
23 ... Second steering shaft (steering transmission system, output shaft)
24 ... EPS actuator (steering transmission system)
25 ... Rod (steering transmission system)
26 ... Steering angle sensor 27 ... Vehicle speed sensor 28 ... Torque sensor 29 ... IGSW sensor 30 ... Lock mechanism 31 ... Housing 32 ... Lock holder 32a ... Engaging recess 33 ... Lock arm 33a ... Engaging projection 35 ... Solenoid 36 ... Torsion coil Spring 40 ... Transmission ratio variable mechanism 40m ... Motor (electric motor)
50 ... IFS_ECU (motor control means)
60 ... EPS_ECU
90 ... CAN
S103, S105, S107, S109 (initialization process)
S111 (Initialization process, process involving rotational driving of the motor, process for ensuring the operation or non-operation of the lock mechanism)
S113 (initialization process, process involving rotation of the motor, process for inspecting the operation or non-operation of the lock mechanism)
FR, FL ... Steering wheel V ... Vehicle speed signal (information about speed)

Claims (3)

A transmission ratio that is provided in the middle of a steering transmission system of a vehicle that couples a steering wheel and a steering wheel, and that can change a transmission ratio between the steering wheel side input shaft and the steering wheel side output shaft by rotation driving of an electric motor. Variable mechanism,
Motor control means capable of controlling the rotational drive of the electric motor;
Vehicle speed information acquisition means capable of acquiring information related to the speed of the vehicle;
A transmission ratio variable device comprising:
The motor control unit is configured to perform initialization processing scheduled to be performed immediately after starting the engine of the vehicle when the vehicle speed is equal to or lower than a predetermined speed based on the information on the speed by the vehicle speed information acquisition unit. A transmission ratio variable device characterized in that it performs a rotation drive. 2. The transmission ratio variable device according to claim 1, further comprising a lock mechanism capable of preventing rotational driving of the electric motor and setting a transmission ratio between the input shaft and the output shaft to 1: 1.
The transmission ratio variable device characterized in that what is accompanied by rotational drive of the electric motor in the initialization processing is to rotationally drive the electric motor to ensure the release of the lock mechanism. 2. The transmission ratio variable device according to claim 1, further comprising a lock mechanism capable of preventing rotational driving of the electric motor and setting a transmission ratio between the input shaft and the output shaft to 1: 1.
What is accompanied by the rotation drive of the electric motor in the initialization process is to inspect the operation or non-operation of the lock mechanism by rotating the electric motor.

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