Patent Publication Number: US-10787854-B2

Title: Vehicular opening/closing body control device and vehicular opening/closing body control method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 U.S.C. § 119 to Japanese Patent Application 2018-008865, filed on Jan. 23, 2018, the entire contents of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     This disclosure relates to a vehicular opening/closing body control device and a vehicular opening/closing body control method. 
     BACKGROUND DISCUSSION 
     In the related art, a vehicular opening/closing body such as a so-called flip-up type back door is opened by being moved upward. In addition, an opening/closing body control device is capable of opening such an opening/closing body using a motor or the like as a driving source. Further, for example, in the opening/closing body control device disclosed in JP 2017-172179 A (Reference 1), a state in which the opening and closing body (back door), which is opened upward, descends (falls) due to gravity is detected by detecting power generated by a motor serving as a driving source, that is, electromotive voltage generated when the motor is brought to a regenerative state. When a failure in opening operation of such an opening/closing body is detected, the operation of the motor is controlled to apply a braking force to the opening/closing body such that the opening/closing body does not fall sharply. 
     In the example of the related art, a control unit of the motor, which is the driving source thereof, shifts to a sleep state when the opening/closing body is stopped. Furthermore, when a descent of the opening/closing body due to gravity is detected as described above, the control unit is activated from the slip state and executes the braking control of the opening/closing body. As a result of this, the power consumption is reduced. 
     However, with the above-described configuration of the related art, due to the execution of the braking control, even after the above-mentioned failure in opening operation has occurred, there is a possibility that the user continues to use the opening/closing body without particularly feeling inconvenience. Due to this, for example, there is a fear that a factor causing the descent due to gravity, such as a failure of a support device, is left unattended, leaving room for improvement in this respect. 
     Thus, a need exists for a vehicular opening/closing body control device and a vehicular opening/closing body control method which are not susceptible to the drawback mentioned above. 
     SUMMARY 
     A vehicular opening/closing body control device according to an aspect of this disclosure includes an opening drive control unit configured to control operation of a drive device configured to drive a vehicular opening/closing body to open the opening/closing body upward, a gravity descent detection unit configured to detect a descent of the opening/closing body opened upward due to gravity, a braking force imparting unit configured to impart a braking force to the opening/closing body whose descent due to gravity is detected, and an opening drive prohibition unit configured to prohibit opening drive by the drive device of the opening/closing body whose descent due to gravity is detected. 
     A vehicular opening/closing body control method according to an aspect of this disclosure includes performing opening drive of a vehicular opening/closing body to open the opening/closing body, detecting a descent of the opening/closing body opened upward due to gravity, imparting a braking force to the opening/closing body whose descent due to gravity is detected, and prohibiting the opening drive of the opening/closing body whose descent due to gravity is detected. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing and additional features and characteristics of this disclosure will become more apparent from the following detailed description considered with the reference to the accompanying drawings, wherein: 
         FIG. 1  is a schematic configuration view of a power back door device; 
         FIG. 2  is a flowchart illustrating a mode of back door control based on an opening drive request; and 
         FIG. 3  is a flowchart illustrating a mode of back door opening drive prohibition control based on detection of a descent due to gravity. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, an embodiment in which a vehicular opening/closing body control device is implemented as a power back door device will be described with reference to the drawings. 
     As illustrated in  FIG. 1 , in a vehicle  1  of the present embodiment, a so-called flip-up back door  10  is provided in a door opening portion  5  formed in the rear end portion  2   r  of a vehicle body  2 . That is, the back door  10  is opened upward (rotates counterclockwise in  FIG. 1 ) using the upper end portion of the door opening  5  as a pivot point. In addition, a pair of support devices (e.g., dampers)  20  are provided at opposite end portions in the width direction of the door opening portion  5 , in which each of the support devices has an expandable shaft shape and axial ends thereof are connected to be pivotable with respect to the vehicle body  2  side and the back door  10  side. In the vehicle  1  of the present embodiment, each of the support devices  20  supports the back door  10  such that the operation position (e.g., in  FIG. 1 , a fully opened position X 1  indicated by a two-dot chain line) of the back door  10 , which has opened upward from the fully closed position X 0  is held. 
     In addition, the vehicle  1  of the present embodiment is provided with a drive device  30  that drives the back door  10  as an opening/closing body thereof using a motor  25  as a driving source. Specifically, a drive device  30  is provided integrally with each of the support devices  20 . That is, the drive device  30  converts the rotation of the motor  25  into an expansion/contraction operation of the support device  20 . The vehicle  1  of the present embodiment is provided with a power back door device  40  capable of opening and closing the back door  10  based on the driving force of the motor  25 . In addition, the drive device  30  may be provided separately from each support device  20 . 
     More specifically, the operation of the drive device  30  of the present embodiment is controlled by a control device  50 . Specifically, the control device  50  of the present embodiment controls the rotation of the motor  25  by supplying driving power based on the power supply voltage Vb of an on-vehicle power supply  51  to the drive device  30 . Further, the drive device  30  of the present embodiment outputs a pulse signal Sp synchronized with the rotation of the motor  25 . Then, the control device  50  is configured to detect the operation position X of the back door  10  by counting the pulse signal Sp (the pulse edges thereof). 
     In addition, the control device  50  is input with an operation input signal Scr indicating that an operation input unit  52  provided in the back door  10 , a portable device (not illustrated), or the like is operated. In the vehicle  1  of the present embodiment, for example, a non-contact sensor such as a capacitance sensor is used as the operation input unit  52 . The control device  50  of the present embodiment is configured to control the operation of the drive device  30  so as to open and close the back door  10  based on the operation request indicated by the operation input signal Scr. 
     Specifically, in the case where the back door  10  is in the fully closed position X 0 , when the operation input unit  52  provided in the back door  10  is operated, the control device  50  of the present embodiment opens the back door  10  to the fully opened position X 1  by driving the back door  10  upward. At this time, the control device  50  opens a door lock device  55  (unlocks a door lock) provided in the back door  10  on the condition that a predetermined cancellation condition is satisfied, such as when a regular portable device (a user possessing the regular portable device) is present within an authentication region set in the vicinity of the back door  10 . In the case where the back door  10  is in the state of being opened, when the operation input unit  52  provided in the back door  10  is operated, the control device  50  of the present embodiment is configured to close the back door  10  to the fully closed position X 0 . 
     More specifically, as described above, the control device  50  of the present embodiment includes a back door control unit  61  that executes operation control of the drive device  30  and the door lock device  55 , and a power source management unit  62  that manages power supply to the back door control unit  61 . In the control device  50  of the present embodiment, the power source management unit  62  executes power supply to the back door control unit  61  when it becomes necessary to control the operation of the back door  10 . Further, when the operation control of the back door  10  is completed, the power source management unit  62  stops the power supply to the back door control unit  61 . Thus, the control device  50  of the present embodiment is configured to reduce the power consumption of the back door control unit  61  by shifting the back door control unit  61  to the sleep state. 
     That is, as illustrated in the flowchart of  FIG. 2 , for example, when the back door  10  is in the fully closed position X 0 , the control device  50  of the present embodiment detects the opening operation request of the back door  10  based on the operation input signal Scr (Step  101 : YES), and the power source management unit  62  starts power supply to the back door control unit  61 . As a result, when the back door control unit  61  is activated from the sleep state, the back door  10  is in the state where the opening drive control of the back door  10  is capable of being executed (wake-up) (step  102 ). 
     Next, the control device  50  of the present embodiment determines whether or not execution permission of door lock release exists (step  103 ), and when it is determined that the execution permission exists (step  103 : YES), the control device  50  controls the operation of the door lock device  55  provided in the back door  10  to release the door lock (door lock release control) (step  104 ). Further, the control device  50  determines whether or not execution permission of opening drive by the drive device  30  exists with respect to the back door  10  (step  105 ). When it is determined that the execution permission exists (step  105 : YES), the operation of the drive device  30  is controlled to execute the opening drive of the back door  10  (back door opening drive control) (step  106 ). 
     In this case, the control device  50  of the present embodiment executes the back door opening drive control of step  106  until the operation position X of the back door  10  reaches the fully opened position X 1  as described above (step  107 : NO). Furthermore, when the back door  10  reaches the fully opened position X 1  (step  107 : YES), the control device  50  terminates the back door opening drive control, whereby the power source management unit  62  stops power supply to the back door control unit  61 . Thus, the control device  50  of the present embodiment is configured to cause the back door control unit  61  to shift again to the sleep state (step  108 ). 
     When the execution permission of the opening drive by the drive device  30  does not exist in the step  105  (step  105 : NO), the control device  50  does not execute the processing of the above-mentioned steps  106  and  107 . When it is determined in step  103  that permission execution of door lock release does not exist (step  103 : NO), the control device  50  does not execute the processing of steps  104  to  107 . 
     In addition, the control device  50  of the present embodiment has a function of detecting occurrence of an opening failure in which the back door  10 , which has been opened upward as described above, descends due to gravity due to the failure of the support device  20  or the like. Specifically, after completion of the opening drive control, the control device  50  monitors a change in the pulse signal Sp output by the drive device  30  while keeping the back door control portion  61  in the sleep state. When detecting the descent due to gravity of the back door  10 , the control device  50  of the present embodiment starts power supply to the back door control unit  61  by the power source management unit  62 . The back door control unit  61  activated from the sleep state thereby controls the operation of the drive device  30 , thereby imparting a braking force to the back door  10 . Thus, the power back door device  40  of the present embodiment is configured so that the back door  10  does not fall sharply even when a failure occurs in the support device  20 . 
     More specifically, as illustrated in the flowchart of  FIG. 3 , the control device  50  of the present embodiment detects the state in which the back door  10 , which has opened upward, descends due to gravity (step  201 : YES), whereby the back door control unit  61  is activated from the sleep state (wake-up) (step  202 ). At this time, the control device  50  determines whether or not an opening drive prohibition flag that prohibits opening drive by the drive device  30  is set for the back door  10  (step  203 ). When it is determined that the opening drive prohibition flag is not set (step  203 : NO), the control device  50  sets an opening drive prohibition flag (step  204 ), and executes the braking control of the back door  10 , which descends due to gravity (step  205 ). 
     Specifically, as the braking control of the back door  10 , the control device  50  of the present embodiment executes control to suppress the rotation of the motor  25  in synchronization with the descent of the back door  10 . Consequently, the control device  50  is configured to cause the back door  10  to perform closing operation while suppressing a speed of the descent due to gravity of the back door  10  by imparting a braking force to the back door  10  (low speed closing operation control). 
     In this case, the control device  50  of the present embodiment executes the back door opening drive control of step  205  until the operation position X of the back door  10  reaches the fully closed position X 0  (step  206 : NO). Furthermore, when the back door  10  reaches the fully closed position X 0  (step  206 : YES), the control device  50  terminates the back door braking drive control, whereby the power source management unit  62  stops power supply to the back door control unit  61 . Thus, the control device  50  is configured to cause the back door control unit  61  to shift to the sleep state again (step  207 ). 
     Meanwhile, when it is determined in step  203  that the opening drive prohibition flag has already been set (step  203 : YES), the control device  50  sets a lock release prohibition flag indicating that the door lock release is prohibited with respect to the back door  10  (step  208 ). Then, similarly to the case where the opening drive prohibition flag is set in step  204 , the control device  50  imparts a braking force to the back door  10  that descends due to gravity by executing the processing of step  205  and steps following step  205 . 
     That is, since the opening drive prohibition flag is set in step  204 , with respect to the opening drive of the back door  10  by the drive device  30  (see  FIG. 2 , step  106 ), it is determined that execution permission does not exist (step  105 : NO). In addition, the power back door device  40  of the present embodiment has a configuration in which, when the descent due to gravity of the back door  10  is detected consequently even if, for example, the operation input unit  52  provided in the back door  10  is operated thereafter, it is unable to perform opening drive of the back door  10  using the drive device  30 . 
     In the power back door device  40  of the present embodiment is configure such that even when the opening drive of the back door  10  by the drive device  30  is prohibited, the back door  10  can be opened manually. However, even in this case, as the lock release prohibition flag is set in step  208 , it is determined with respect to the back door  10  that execution permission of the door lock release (see  FIG. 2 , step  104 ) does not exist (step  103 : NO in the same drawing). 
     That is, the power back door device  40  of the present embodiment is configured such that even when the back door  10  is in the fully closed state after the descent due to gravity of the back door  10 , which has been opened by being driven by the drive device  30 , is detected, it is possible to perform door unlocking once and to manually open the back door  10 . In the case where a descent due to gravity is detected again in the back door  10 , which has been manually opened, thereafter, by preventing unlocking after the back door  10  moves to the fully closed position X 0 , the fully closed state of the back door  10  is maintained. That is, the power back door device  40  has a configuration in which until the cause of the descent due to gravity of the back door  10  is eliminated, for example, until the failure of the support device  20  is repaired, the back door  10  does not open. 
     When the descent due to gravity of the opened back door  10  is not detected for a predetermined time or longer (step  201 : NO and step  209 : YES), the control device  50  of the present embodiment determines whether or not an opening drive prohibition flag is set for the back door  10  (step  210 ). Then, when it is determined that the opening drive prohibition flag is set (step  210 : YES), the control device  50  is configured to clear the opening drive prohibition flag (step  211 ). 
     In other words, when the back door  10 , for which the opening driving by the drive device  30  is prohibited, is in the opened state, it is presumed that the back door  10  is manually opened. Furthermore, when a descent due to gravity is not detected for the back door  10 , the control device  50  of the present embodiment regards that the cause of the descent due to gravity has been eliminated. Consequently, the power back door device  40  of the present embodiment is configured to return to a state where the opening drive of the back door  10  is capable of being performed by the drive device  30 . 
     In addition to the case where the descent due to gravity of the opened back door  10  is not detected for a predetermined period of time or longer, a canceling means based on a special operation, such as clearing the set opening drive prohibition flag by the control device  50  by detecting a release signal through communication with an external device, may be set. This makes it possible to enhance convenience, for example, when a failure is repaired at a repair shop. 
     Next, effects of the present embodiment will be described. 
     (1) The control device  50  as an opening drive control unit  70   a  controls the operation of the drive device  30  to open the back door  10  constituting an opening/closing body of the vehicle  1  upward. In addition, the control device  50  as a gravity descent detection unit  70   b  detects that the upwardly opened back door  10  is in a state of descending due to gravity (step  201 : YES). Further, the control device  50  as a braking force imparting  70   c  imparts a braking force to the back door  10  for which a descent due to gravity is detected (step  205 ). Furthermore, the control device  50  as an opening drive prohibition unit  70   d  prohibits the opening drive by the drive device  30  with respect to the back door  10 , for which the descent due to gravity is detected (step  204 ). 
     According to the above-described configuration, even when the back door  10  is in the state of descending due to gravity, such as a failure of the support device  20 , it is possible to prevent the back door  10  from falling sharply, thereby ensuring high safety. Further, thereafter, it is unable to open the back door  10  by the drive device  30 . Consequently, by informing the user of the opening failure occurring in the back door  10 , it is possible to urge the user to repair the back door  10 . 
     (2) When a descent due to gravity is not detected for the back door  10  for which opening drive by the drive device  30  is prohibited (step  201 : NO, step  209 : YES, and step  210 : YES), the control device  50  as a drive prohibition canceling unit  70   e  cancels the prohibition of the opening drive set for the back door  10  (step  211 ). 
     That is, even when a descent due to gravity of the back door  10  has been detected, it may be regarded that the cause of occurrence of the opening failure, which occurred at the previous opening drive, is eliminated when a descent due to gravity is not detected when the back door  10  is manually opened upward next time. Consequently, it is possible to open the back door  10  again using the drive device  30 , whereby it is possible to improve convenience. 
     (3) When a descent due to gravity is detected again with respect to the back door  10  for which opening drive by the drive device  30  is prohibited (step  201 : YES, and step  203 : YES), the control device  50  as a drive prohibition canceling unit  70   e  prohibits the door unlocking for the back door  10  (step  208 ). 
     According to the above-described configuration, it is no longer possible to open the back door  10  held at the fully closed position X 0 . Consequently, it is possible to ensure high safety and to more effectively urge the user to repair an opening failure caused in the back door  10 . 
     (4) The control device  50  controls the drive device  30  to impart a braking force to the back door  10 , thereby moving the back door  10  to the fully closed position X 0  while suppressing a speed of the descent due to gravity. Consequently, it is possible to ensure high safety by preventing occurrence of so-called pinching. 
     (5) The control device  50  includes a back door control unit  61  as an opening/closing body control unit functioning as an opening drive control unit  70   a  and a braking force imparting unit  70   c  for the drive device  30  by controlling the operation of the drive device  30 , and a power source management unit  62  that manages power supply to the control unit  61 . When the opening drive of the back door  10  by the drive device  30  is completed, the power source management unit  62  stops the power supply to the back door control unit  61 , and shifts the back door control unit  61  to the sleep state. Then, the power source management unit  62  activates the back door control unit  61  from the sleep state by detecting a descent due to gravity of the back door  10 . Consequently, it is possible to reduce power consumption. 
     The above-described embodiment may be implemented with the following modifications. The above-described embodiment and the following modifications can be implemented in combination with each other to the extent that they do not conflict technically.
         In the above-described embodiment, the present disclosure is implemented as a power back door device  40  that opens and closes a back door  10  as an opening/closing body provided in the rear end portion  2   r  of a vehicle body  2 . However, the present disclosure is not limited to this and is applicable to any opening and closing body such as a so-called gull wing type side door or a trunk lid, as long as the opening and closing body of the vehicle  1  as an object to be controlled is opened upward.   In the above-described embodiment, when a descent by gravity of the back door  10  is detected, the drive device  30  is controlled to impart a braking force to the back door  10 , thereby moving the back door  10  to the fully closed position X 0  while suppressing descent speed due to gravity. However, the present disclosure is not limited to this, and a configuration may be adopted in which the operation position X of the opened back door  10  is held by imparting the braking force. Further, as long as the braking force is substantially imparted, for example, a configuration may be adopted in which the low-speed closing drive control of the back door  10  is performed. Further, the operation position X for holding the back door  10  is not necessarily the fully opened position X 1 . A configuration may be adopted in which a braking force may be imparted to the back door  10  by controlling the operation of a brake device provided separately from the drive device  30 .   In the above-described embodiment, a descent by gravity of the back door  10  is detected by monitoring the change of a pulse signal Sp synchronized with the rotation of the motor  25 , which is the drive source of the drive device  30 . However, without being limited to this, the method of detecting the descent due to gravity of the back door  10  may be arbitrarily changed. For example, an electromotive force (power generation state) generated when the motor  25  is turned into a regenerative state may be monitored.   In the above-described embodiment, the power consumption of the control device  50  is reduced by executing the sleep control of the back door control unit  61 . However, this may be implemented with a configuration in which such sleep control is not performed.   In the above-described embodiment, the drive device  30  is configured to be capable of opening and closing the back door  10 , but it may be applied to a configuration in which only opening drive is performed.       

     A vehicular opening/closing body control device according to an aspect of this disclosure includes an opening drive control unit configured to control operation of a drive device configured to drive a vehicular opening/closing body to open the opening/closing body upward, a gravity descent detection unit configured to detect a descent of the opening/closing body opened upward due to gravity, a braking force imparting unit configured to impart a braking force to the opening/closing body whose descent due to gravity is detected, and an opening drive prohibition unit configured to prohibit opening drive by the drive device of the opening/closing body whose descent due to gravity is detected. 
     According to the above-described configuration, even when the opening/closing body is in the state of descending due to gravity, such as a failure of a support device, it is possible to prevent the opening/closing body from falling sharply, thereby ensuring high safety. Thereafter, the opening/closing body becomes unable to be opened by the drive device. Consequently, by informing the user of the opening failure occurring in the opening/closing body, it is possible to urge the user to repair the opening/closing body. 
     It is preferable that the vehicle opening/closing body control device according to the aspect of this disclosure further includes a drive prohibition canceling unit configured to cancel the prohibition of the opening drive when the descent due to gravity is not detected with respect to the opening/closing body for which the opening drive is prohibited. 
     That is, even when a descent due to gravity of the opening/closing body has been detected, it may be regarded that the cause of occurrence of the opening failure, which occurred at the previous opening drive, is eliminated when a descent due to gravity is not detected when the opening/closing body is manually opened upward next time. Consequently, it is possible to open the opening/closing body again using the drive device, whereby it is possible to improve convenience. 
     It is preferable that the vehicular opening/closing body control device according to the aspect of this disclosure further includes an unlocking prohibition unit configured to prohibit unlocking of the opening/closing body and hold the opening/closing body at a fully closed position when the descent due to gravity is detected with respect to the opening/closing body for which the opening drive is prohibited. 
     According to the above-described configuration, it is no longer possible to open the opening/closing body held at the fully closed position. Consequently, it is possible to ensure high safety and to more effectively urge the user to repair an opening failure caused in the opening/closing body. 
     In the vehicle opening/closing body control device according to the aspect of this disclosure, it is preferable that the braking force imparting unit moves the opening/closing body to the fully closed position while suppressing a speed of the descent due to gravity by imparting the braking force to the opening/closing body. 
     According to the above-described configuration, it is possible to ensure high safety by preventing occurrence of so-called pinching. 
     It is preferable that the vehicular opening/closing body control device according to the aspect of this disclosure further includes an opening/closing body control unit configured to function as the opening drive control unit and the braking force imparting unit by controlling the operation of the drive device, and a power source management unit configured to manage power supply to the opening/closing body control unit, in which, when the opening drive is completed, the power source management unit stops the power supply to the opening/closing body control unit and shifts the opening/closing body control unit to a sleep state, and when the descent due to gravity of the opening/closing body is detected, the power source management unit initiates power supply to the opening/closing body control device and activates the opening/closing body control unit from the sleep state. 
     With the above-described configuration, it is possible to reduce power consumption. 
     A vehicular opening/closing body control method according to an aspect of this disclosure includes performing opening drive of a vehicular opening/closing body to open the opening/closing body, detecting a descent of the opening/closing body opened upward due to gravity, imparting a braking force to the opening/closing body whose descent due to gravity is detected, and prohibiting the opening drive of the opening/closing body whose descent due to gravity is detected. 
     According to the aspects of this disclosure, it is possible to ensure high safety by suppressing a descent due to gravity of the opening/closing body, and urge the user to repair an opening failure caused in the opening/closing body. 
     The principles, preferred embodiment and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby.