JP4498075B2 - Motor retractor - Google Patents

Description

  The present invention relates to a webbing take-up device, and more particularly to a motor retractor that can take up a webbing by rotating a take-up shaft with a motor.

  A vehicle such as a passenger car is provided with a seat belt device for restraining an occupant seated on the seat by a long belt-like webbing. Of these, a so-called three-point seat belt device is wound so that the webbing can be pulled out. A retractor (webbing take-up device) is provided for storing in a state of being stored.

  The retractor includes a winding shaft that winds the webbing from the proximal end side when the longitudinal direction proximal end side of the webbing is locked and rotates, a spiral spring that biases the winding shaft in the winding direction of the webbing, and the like The urging member is provided. In the seat belt device provided with the retractor, when the occupant is wearing the webbing, the winding shaft is biased in the winding direction of the webbing by the biasing force of the biasing member, thereby removing the slack. The webbing restrains the occupant. When the occupant releases the webbing wearing state, the webbing is wound around the winding shaft by the biasing force of the biasing member.

  Here, when the urging force of the urging member is small, the webbing is not wound up to the end and is in a slack state, which causes a deterioration in appearance when the webbing is not used. On the other hand, when the urging force of the urging member is large, it causes a feeling of pressure to the occupant wearing the webbing.

  For this reason, the urging force of the urging member is reduced to alleviate (suppress) the feeling of pressure applied to the occupant, and in order to compensate for the decrease in the webbing take-up force on the take-up shaft due to this urging force reduction, A motor retractor having a mechanism (so-called “storage assist mechanism”) that drives a take-up shaft by force has been considered (see, for example, Patent Document 1).

  In a motor retractor having such a storage assist mechanism, generally, a clutch is provided between the motor and the winding shaft, and only rotation from the output shaft side of the motor is transmitted to the winding shaft. It is configured.

  Specifically, when the occupant releases the webbing state, the motor is rotated, so that the clutch connects the motor output shaft and the take-up shaft, so that the rotation of the motor is applied to the take-up shaft. Then, the winding shaft is rotated in the webbing winding direction. As a result, the reduction of the urging force of the urging member is compensated, and the webbing is wound and stored on the winding shaft.

By the way, in such a motor retractor, when the occupant pulls out the webbing during rewinding of the webbing, the connection state between the motor output shaft and the winding shaft by the clutch is maintained. However, there is a problem that the feeling of pulling out the webbing is deteriorated, and some measures are required to pull out the webbing against the driving force of the rotating motor.
JP 2001-163186 A

  In consideration of the above-described facts, the present invention improves the clutch release performance when the webbing remounting operation is performed, can suppress the occurrence of discomfort and incongruity in the webbing drawer, and does not compress the occupant when the webbing is mounted. It aims at obtaining the motor retractor which can also secure the property.

In order to solve the above problems, a motor retractor according to a first aspect of the present invention is a belt-like webbing that restrains the body of an occupant in a state of being mounted on an occupant seated on a vehicle seat, and a longitudinal direction of the webbing. The direction base end side is locked, and the webbing is wound so that the webbing can be wound, and the winding shaft is connected to the winding shaft, and the urging force corresponding to the occupant non-compressibility in the webbing wearing state It is interposed between a biasing member that biases the winding shaft in the webbing winding direction, a motor, and the winding shaft and the output shaft of the motor, and transmits the normal rotation of the motor to the winding shaft. The winding shaft is rotated in the webbing winding direction, and the clutch is released by a predetermined amount of relative rotation between the output shaft and the winding shaft due to the reverse rotation of the motor, and the forward rotation of the motor. By said web When an external force that the winding middle occupant against the winding-up of the webbing is pulled out webbing grayed detects the constraint current flowing in the motor by acting reverses the motor, and thereafter, the output Control means for continuing the reverse rotation of the motor until the shaft rotates at least the predetermined amount relative to the winding shaft and the clutch is released.

  In the motor retractor according to the first aspect, when the occupant seated in the vehicle seat pulls the webbing stored in the motor retractor, the webbing is pulled out while the winding shaft rotates. Accordingly, the occupant can put the webbing on the body by hanging the pulled-out webbing around the body and, for example, engaging the tongue plate provided on the webbing with the buckle device.

  In this state, the take-up shaft is urged in the webbing take-up direction by the urging force of the urging member. Therefore, even when the webbing attached to the occupant is loosened, the slack is not applied to the urging member. It is removed with a winding force according to the biasing force. Moreover, since the urging force of the urging member corresponds to the occupant non-compressing property in the state where the webbing is worn, the occupant wearing the webbing does not give a feeling of pressure.

  On the other hand, when the occupant removes the webbing (for example, when the engagement between the tongue plate and the buckle device described above is released), the output shaft of the motor rotates forward. The normal rotation of the motor is transmitted to the winding shaft via the clutch, and the winding shaft is rotated in the webbing winding direction. As a result, the webbing is wound around the winding shaft.

Here, in the motor retractor according to the first aspect, the control means is such that the external force acting against the winding of the webbing acts while the webbing is being wound around the winding shaft by the forward rotation of the motor as described above. When the restraint current flowing in the motor is detected , the motor is reversed, and thereafter, the rotation of the motor is continued until the output shaft rotates at least a predetermined amount relative to the winding shaft and the clutch is released.

For example, when the occupant pulls out the webbing in the middle of winding the webbing due to the normal rotation of the motor, an external force acts against the winding of the webbing and a binding current flows through the motor . The control means immediately reverses the motor (rotates the output shaft in the rotation direction corresponding to the webbing pull-out direction and in the clutch release direction). As a result, the output shaft and the winding shaft rotate in synchronization with each other, so that it is possible to prevent the webbing drawer from feeling uncomfortable or uncomfortable. The take-up shaft stops when the webbing is pulled out by the occupant. From this point, the control means further rotates the output shaft relative to the take-up shaft by a predetermined amount until the clutch is released. Continue reversing. Therefore, the clutch is reliably released after a predetermined time has elapsed since the time when the occupant canceled the withdrawal of the webbing.

In addition, for example, when the occupant pulls out the webbing relatively slowly (including the case of only grabbing the webbing) in the middle of winding the webbing by forward rotation of the motor, Since an external force is generated against the removal and a binding current flows through the motor, the control means immediately reverses the motor. In this case, since the winding shaft rotates or stops at a low speed, the output shaft quickly rotates relative to the winding shaft by a predetermined amount and the clutch is immediately released. When the clutch is released, the control means stops the reverse rotation of the motor. In this state, the winding shaft can freely rotate by releasing the clutch. Therefore, if the occupant subsequently pulls out the webbing, the occupant can smoothly pull out the webbing, and it is possible to suppress uncomfortable feeling and uncomfortable feeling in the webbing drawer.

  As described above, in the motor retractor according to the first aspect, the release of the clutch when the webbing remounting operation is performed can be improved, and it is possible to prevent the webbing from being uncomfortable and uncomfortable, and the webbing mounted state It is possible to secure the non-compressibility of the passengers.

  A motor retractor according to a second aspect of the present invention is the motor retractor according to the first aspect, wherein the control means determines whether or not the clutch is released based on each rotation time of the output shaft and the winding shaft. It is characterized by that.

  In the motor retractor according to the second aspect, the control means determines whether or not the clutch is released based on the rotation time of the output shaft (the energization time of the motor) and the rotation time of the winding shaft. A special detection mechanism for detecting the released state of the clutch is unnecessary and is preferable.

  The motor retractor of the invention according to claim 3 is a belt-like webbing that restrains the occupant's body in a state of being mounted on an occupant seated on a vehicle seat, and a longitudinal base end side of the webbing is locked. A winding shaft on which the webbing is wound so that the webbing can be withdrawn, and the winding shaft is connected to the winding shaft, and the winding shaft is connected to the winding shaft by an urging force corresponding to an occupant non-pressing property when the webbing is mounted. A biasing member that biases in the direction, a motor, and the winding shaft and an output shaft of the motor, the forward rotation of the motor being transmitted to the winding shaft to transmit the winding shaft to the winding shaft; A clutch that rotates in the webbing take-up direction and maintains a connected state between the output shaft and the take-up shaft in the retracted state of the webbing, and when the occupant wears the webbing when the occupant gets on the Mo The output shaft and the winding shaft are rotated relative to each other by a predetermined amount to bring the clutch into a released state, and the occupant releases the webbing and stores the webbing. Control means for reversely rotating the motor longer than the predetermined time when the occupant is present in the vehicle interior later.

  In the motor retractor according to the third aspect, when the occupant seated in the vehicle seat pulls the webbing stored in the motor retractor, the webbing is pulled out while the winding shaft rotates. Accordingly, the occupant can put the webbing on the body by hanging the pulled-out webbing around the body and, for example, engaging the tongue plate provided on the webbing with the buckle device.

  In this state, the take-up shaft is urged in the webbing take-up direction by the urging force of the urging member. Therefore, even when the webbing attached to the occupant is loosened, the slack is not applied to the urging member. It is removed with a winding force according to the biasing force. Moreover, since the urging force of the urging member corresponds to the occupant non-compressing property in the state where the webbing is worn, the occupant wearing the webbing does not give a feeling of pressure.

  On the other hand, when the occupant removes the webbing (for example, when the engagement between the tongue plate and the buckle device described above is released), the output shaft of the motor rotates forward. The normal rotation of the motor is transmitted to the winding shaft via the clutch, and the winding shaft is rotated in the webbing winding direction. Thereby, the webbing is wound and stored on the winding shaft. In this state where the webbing is stored, the clutch maintains the connection state between the output shaft and the winding shaft.

  Here, in the motor retractor according to the third aspect, the control means causes the output shaft and the take-up shaft to rotate relative to each other by a predetermined amount by reversing the motor for a predetermined time when the occupant wears the webbing when the occupant gets on. When the occupant is present in the vehicle compartment after the occupant releases the webbing and the webbing is stored, the motor is reversed for longer than the predetermined time.

  Therefore, for example, when the occupant pulls out the webbing to reattach the webbing simultaneously with the reverse rotation of the motor after storing the webbing, that is, the output shaft cannot rotate relative to the winding shaft by a predetermined amount, and the clutch is connected. Even when the state is maintained, the output shaft and the winding shaft rotate in synchronization with each other, so that it is possible to suppress uncomfortable feeling and uncomfortable feeling in the webbing drawer. In addition, since the control means reverses the motor longer than the predetermined time required for releasing the clutch, after the webbing is pulled out by the occupant and the winding shaft is stopped, the output shaft is rotated by a predetermined amount with respect to the winding shaft. The clutch is released by relative rotation.

  Thus, in the motor retractor according to the third aspect, the release of the clutch is improved when the webbing is remounted, and it is possible to suppress the discomfort and discomfort from pulling out the webbing, and the webbing mounted state It is possible to secure the non-compressibility of the passengers.

  As described above, in the motor retractor according to the present invention, the release of the clutch when the webbing is remounted is improved, and it is possible to prevent the webbing drawer from being uncomfortable or uncomfortable and the webbing mounted state. It is possible to secure the non-compressibility of the passengers.

<First Embodiment>
FIG. 1 is a front sectional view showing the overall configuration of a motor retractor 10 according to a first embodiment of the present invention.

  As shown in FIG. 1, the motor retractor 10 includes a frame 12. The frame 12 includes a substantially plate-like back plate 14, and the motor retractor 10 is attached to the vehicle body by fixing the back plate 14 to the vehicle body by fastening means (not shown) such as bolts. . A pair of leg plates 16 and 18 extend in parallel from both ends of the back plate 14 in the width direction, and a spool 20 as a winding shaft manufactured by die casting or the like is rotatable between the leg plates 16 and 18. Has been placed.

  The spool 20 includes a substantially cylindrical spool main body 22 and a pair of flange portions 24 and 26 formed in a substantially disc shape at both ends of the spool main body 22, respectively. Yes.

  A base end portion of a webbing 28 formed in a long band shape is connected and fixed to the spool body 22, and the spool 20 is rotated around one axis (hereinafter, this direction is referred to as “winding direction”). Then, the webbing 28 is wound around the outer periphery of the spool body 22 in a layered manner from the base end side. On the other hand, when the webbing 28 is pulled from the front end side, the webbing 28 is pulled out while the spool 20 is rotated (hereinafter, the rotation direction of the spool 20 when the webbing 28 is pulled out is referred to as a “drawing direction”).

  The one end side of the spool 20 on the side opposite to the flange portion 26 of the flange portion 24 penetrates a circular hole 30 formed in the leg plate 16 substantially coaxially and protrudes to the outside of the frame 12. A case 32 is disposed outside the frame 12 on the leg plate 16 side. The case 32 is disposed facing the leg plate 16 along the axial direction of the spool 20 and is fixed to the leg plate 16. The case 32 is generally open toward the leg plate 16, and one end side of the spool 20 that penetrates the circular hole 30 enters the inside of the case 32 and is rotatably supported by the case 32.

  Further, a spiral spring 34 is disposed inside the case 32. The spiral spring 34 has an end on the outer side in the spiral direction locked with the case 32, and an end on the inner side in the spiral direction locked with the spool 20. The spiral spring 34 biases the spool 20 in the winding direction.

  The biasing force of the spiral spring 34 (based on the winding force of the webbing 28) is set to be relatively weak enough to eliminate the slackness of the webbing 28 worn by the occupant. In other words, the urging force of the spiral spring 34 is set so as to have a strength corresponding to the occupant non-compressing property when the webbing 28 is attached, and the webbing 28 pulled out from the spool 20 resists the frictional force and the like. The strength to wind up is not required.

  On the other hand, the spool 20 includes a support shaft portion (not shown) that projects coaxially from the end portion on the flange portion 26 side. The support shaft portion passes through an internal ratchet hole 36 formed in the leg plate 18 substantially coaxially and protrudes to the outside of the frame 12, and is fixed in a state where the open end is abutted against the outer surface of the leg piece 18. Then, it is rotatably supported by a substantially cup-shaped case 40 constituting the lock mechanism 38.

  The lock mechanism 38 normally allows the spool 20 to freely rotate in the winding direction and the pulling direction, and prevents the spool 20 from rotating in the pulling direction when the vehicle suddenly decelerates. In the first embodiment, when the acceleration sensor 41 prevents rotation of the ratchet gear 42 in the pull-out direction, the lock plate 46 protrudes from the lock base 44 due to the relative rotation of the ratchet gear 42 and the spool 20, and the leg piece 18. Is engaged with the inner teeth of the ratchet hole 36 to prevent the spool 20 from rotating in the pull-out direction. A structure in which a torsion bar is connected between the lock base 44 and the spool 20 to absorb the energy by allowing the spool 20 to rotate in the pull-out direction while twisting the torsion bar after the lock (acting a force limiter function). It is also good.

  On the other hand, a motor 60 is disposed between the leg plate 16 and the leg plate 18 below the spool 20. A gear 64 is coaxially and integrally provided on the output shaft 62 of the motor 60.

  A gear 66 having a larger diameter than that of the gear 64 is disposed above the gear 64 in the radial direction. The gear 66 meshes with the gear 64 in a state of being rotatably supported around an axis parallel to the spool 20 by the support plate 68 and the leg plate 16 provided between the leg plates 16 and 18. A gear 70 having a smaller diameter than the gear 66 is provided coaxially and integrally with the gear 66 on the side of the gear 66 in the axial direction.

  Further, a clutch 72 is provided on the upper side of the gear 70 in the radial direction. The clutch 72 includes an external gear 74 formed in a ring shape. The gear 74 is provided so as to be coaxial and relative to the spool 20 while being engaged with the gear 70, and both ends in the axial direction are closed by disk-like members (not shown). A cylindrical adapter 76 is provided coaxially with the spool 20 inside the gear 74. The adapter 76 is integrally connected to the spool 20 and pivotally supports the disk-like member and thus the gear 74 so as to be rotatable around the spool 20 in a state where the both ends of the gear 74 are closed. Yes.

  Inside the gear 74, for example, a coupling member (not shown) such as a pawl that swings due to centrifugal force is accommodated. For example, the connecting member is supported by the disk-shaped member and is rotated integrally with the gear 74.

  Here, in this clutch 72, the rotational force of the output shaft 62 of the motor 60 is transmitted to the gear 74 via the gear 64, the gear 66, and the gear 70 (the output shaft 62 and the gear 74 always rotate in synchronization). When the output shaft 62 of the motor 60 rotates in the forward direction (forward rotation), the gear 74 rotates in the winding direction. When the gear 74 rotates in the winding direction, the connecting member is mechanically coupled to the outer peripheral surface of the adapter 76 so that the gear 74 and the adapter 76 are integrally connected. Accordingly, the rotation of the gear 74 in the winding direction (forward rotation of the motor 60) is transmitted to the spool 20 via the adapter 76.

  On the other hand, when the output shaft 62 of the motor 60 rotates in the reverse direction (reverse rotation), the gear 74 rotates in the pull-out direction. In this case, when the gear 74 rotates relative to the adapter 76 by a predetermined amount in the pulling direction (when the output shaft 62 rotates relative to the spool 20 by a predetermined amount due to the reverse rotation of the motor 60), the connecting member relative to the adapter 76 is reached. The mechanical coupling is released, and the clutch 72 is released.

  On the other hand, the motor retractor 10 includes a driver 82 and an ECU 86 that constitute control means. The ECU 86 stores a drive control program according to the first embodiment of the present invention. In addition, the motor 60 is electrically connected to a battery 84 mounted on the vehicle via a driver 82, and the current from the battery 84 flows to the motor 60 via the driver 82. Thus, the output shaft 62 is rotated forward or reverse. The driver 82 is connected to the ECU 86, and the ECU 86 controls the presence / absence of power supply to the motor 60 via the driver 82, the direction and magnitude of the supply current. In addition, in this case, the ECU 86 can store the energization time to the motor 60 (particularly, the energization time T1 when the motor 60 is reversely rotated).

  The ECU 86 is connected to a spool rotation detection sensor 88 (magnetic sensor in the first embodiment) that constitutes a control means. The spool rotation detection sensor 88 corresponds to a magnet 90 provided on the outer peripheral portion of the flange portion 26, and the magnet 90 repeatedly passes in the vicinity of the spool rotation detection sensor 88 due to the rotation of the flange portion 26 (spool 20). Then, the magnetism generated by the magnet 90 is detected, and a predetermined electrical signal (hereinafter, this signal is referred to as “detection signal”) is output to the ECU 86.

  In this case, the ECU 86 detects the rotation speed and rotation time of the spool 20 (particularly, the rotation time T2 in the pulling direction of the spool 20) based on the detection signal output from the spool rotation detection sensor 88, and the detected rotation. The winding amount of the webbing 28 is detected from the number. Based on the winding amount of the webbing 28, the ECU 86 outputs a control signal for controlling the driving of the motor 60 to the driver 82, and the driver 82 is operated based on the control signal to drive the motor 60. Be controlled.

  Further, the ECU 86 is connected to a buckle switch 92 as a control means for detecting whether or not a tongue plate provided on the webbing 28 is coupled to a buckle device (both not shown). When the tongue plate is connected to the buckle device, the buckle switch 92 outputs an H level signal indicating the switch ON state to the ECU 86, and when the tongue plate is released from the buckle device, the switch OFF state. Is output to the ECU 86. The ECU 86 determines that the webbing 28 is stored when the signal output from the buckle switch 92 is an L level signal.

  In this case, the ECU 86 causes the motor 60 to rotate forward when it is detected that the tongue plate provided on the webbing 28 has been released from the buckle device (that the webbing 28 has been removed from the passenger when the passenger gets off). When it is detected that all 28 have been stored, a control signal is output to the driver 82 so as to stop the forward rotation of the motor 60. The state in which all the webbings 28 are stored is detected when, for example, the number of rotations of the spool 20 reaches a predetermined number of times set in advance corresponding to the winding amount when all the webbings 28 are stored. It is determined by the ECU 86 by detecting that the rotation speed of the motor 20 has become 0, or by detecting a binding current in the motor 60.

  In addition, a door opening / closing sensor 94 and a seating sensor 96 are connected to the ECU 86. The ECU 86, the door opening / closing sensor 94, and the seating sensor 96 detect a preparation state in which the occupant is about to wear the webbing 28 when the occupant gets on the vehicle. This mounting preparation state includes a state in which the occupant is seated, a door of the vehicle that opens and closes a predetermined number of times after the webbing 28 is fully stored (for example, “opening and closing the door when the passenger gets off” after the webbing is fully stored) Next, the state of “opening and closing the door in the case of occupant riding” performed two times in total is included.

  The door opening / closing sensor 94, together with the ECU 86, detects a state where the door of the vehicle has been opened and closed a predetermined number of times after the webbing 28 has been fully stored. The seating sensor 96 detects a state in which an occupant is seated together with the ECU 86. When such a mounting preparation state is detected, the ECU 86 and the driver 82 reverse the motor 60 by a predetermined amount so that the clutch 72 can be released and the spool 20 can rotate. It has become.

  Further, the ECU 86 is connected to a restraint current detection circuit 98 that constitutes a control means. The restraint current detection circuit 98 is connected to the motor 60 via a driver 82. When the output shaft 62 of the motor 60 is locked and a restraint current flows to the motor 60 (driver 82), a predetermined electric signal (hereinafter referred to as a “electrical signal”) is obtained. This signal is referred to as a “lock detection signal”).

  Here, in the motor retractor 10, during the winding of the webbing 28 due to the normal rotation of the motor 60 (when the buckle switch 92 is off and the webbing 28 is not fully retracted), an external force against the winding of the webbing 28 is applied. When acted (for example, when an occupant pulls out the webbing 28 to reattach the webbing 28), the output shaft 62 of the motor 60 is locked, so that a restraint current flows through the motor 60 and the ECU 86 restrains. A lock detection signal is output from the current detection circuit 98. In this case, the ECU 86 and the driver 82 are configured to rotate the gear 74 of the clutch 72 in the pull-out direction by rotating the motor 60 in the reverse direction.

  The timing at which the ECU 86 and the driver 82 stop the reverse rotation of the motor 60 is such that after the spool 20 (adapter 76) stops rotating in the pull-out direction, the gear 74 relatively rotates in the pull-out direction by a predetermined amount, and the clutch 72 It is said that it is after the time of release. In other words, the rotation time T2 in the pull-out direction of the spool 20 (adapter 76) T1 (also in the case of 0) from the energization time (rotation time in the pull-out direction of the gear 74) T1 to reversely rotate the motor 60. The value (T1-T2) obtained by subtracting (including) exceeds the predetermined value X set in advance.

  In addition, in this case, the predetermined value X is a relative rotation of the gear 74 by a predetermined amount in the pull-out direction with respect to the adapter 76 (spool 20) by the reverse rotation of the motor 60 with the clutch 72 engaged and the spool 20 stopped. Thus, the predetermined time is set longer than the time required for releasing the clutch 72 (predetermined value X = time required for releasing the clutch 72 + α).

  Next, the operation of the first embodiment of the present invention will be described with reference to the flowchart of the drive control program shown in FIG.

  When the tongue plate provided on the webbing 28 is released from the buckle device and the buckle switch 92 is turned off (step 100), the ECU 86 determines that the webbing 28 has been removed from the occupant's body when the occupant gets off, and proceeds to step 102. To do.

  In step 102, the ECU 86 and the driver 82 cause the output shaft 62 of the motor 60 to rotate forward. The forward rotation of the motor 60 is transmitted to the gear 74 of the clutch 72 via the gear 64, the gear 66, and the gear 70, and the gear 74 is rotated in the winding direction. As a result, the clutch 72 is engaged, the driving force of the motor 60 is transmitted to the spool 20 via the clutch 72, and the spool 20 is rotated in the winding direction. For this reason, the webbing 28 is forcibly wound around the spool 20. When winding of the webbing 28 is started, the process proceeds to the next step 104.

  In step 104, based on the detection signal from the spool rotation detection sensor 88, whether or not the rotation speed of the spool 20 has reached a predetermined rotation speed set in advance corresponding to the winding amount when all the webbing 28 is stored. It is determined by the ECU 86. Here, the ECU 86 detects the winding amount of the webbing 28 based on the detected rotational speed of the spool 20, and whether or not the winding amount of the webbing 28 is the winding amount when the webbing 28 is fully stored. Determine whether.

  If the determination in step 104 is affirmative, it is determined that the number of windings of the webbing 28 has reached the winding amount when all the webbing 28 is stored, and the process proceeds to step 106. On the other hand, if the determination in step 104 is negative, it is determined that the winding amount of the webbing 28 has not reached the winding amount when the entire webbing 28 is stored, and the routine proceeds to step 114.

  If the determination in step 104 is affirmative and the routine proceeds to step 106, the webbing 28 has been fully retracted in step 106 because the webbing 28 has been fully retracted. At that time, the ECU 86 and the driver 82 stop the motor 60, and the winding operation of the webbing 28 when the webbing 28 is retracted is completed. In this step 106, the motor 60 remains connected to the spool 20 via the clutch 72. As a result, the spool 20 is prevented from rotating and the wound webbing 28 is prevented from being pulled out of the spool 20. Accordingly, the webbing 28 is prevented from being pulled out of the motor retractor 10 due to the weight of the tongue plate, the vibration of the vehicle, and the like, and the appearance when the webbing 28 is not used can be prevented from deteriorating.

  When the processing in step 106 is completed, the process proceeds to the next step 108 while the motor 60 remains connected to the spool 20 via the clutch 72.

  In step 108, it is determined whether or not the occupant is ready to wear the webbing 28 when riding. Only when this determination is affirmed, the process proceeds to the next step 110.

  In step 110, since the mounting preparation state is detected by the ECU 86, the door opening / closing sensor 94, and the seating sensor 96, the ECU 86 and the driver 82 reverse the motor 60 by a predetermined amount. As a result, the clutch 72 is released and the spool 20 can freely rotate. In this case, only the spiral spring 34 biases the spool 20 in the winding direction of the webbing 28, and the biasing force of the spiral spring 34 is set to a relatively weak biasing force corresponding to the occupant non-compressibility. The occupant can easily pull out the webbing 28 from the motor retractor 10 and attach it.

  Further, when the occupant wears the webbing 28, the spool 20 is urged in the winding direction of the webbing 28 by the spiral spring 34, so that even if the webbing 28 attached to the occupant is slackened. The slack is removed by the winding force of the webbing 28 corresponding to the biasing force of the spiral spring 34. Here, since the urging force of the spiral spring 34 (based on the winding force of the webbing 28) has a strength corresponding to the occupant non-compressibility, the occupant wearing the webbing 28 can be given a feeling of pressure. Absent.

  When the process in step 110 is completed, the process proceeds to the next step 112 and the drive control program is terminated.

  On the other hand, if the determination in step 104 described above is negative and the process proceeds to step 114, in this step 114, it is determined in the ECU 86 whether or not a lock detection signal is output from the binding current detection circuit 98.

  If the determination in step 114 is affirmative, it is determined that the occupant has pulled out the webbing 28 in an attempt to reattach the webbing 28 during winding (storage) of the webbing 28, and the process proceeds to the next step 116. . On the other hand, if the determination in step 114 is negative, the process returns to step 104 and the above-described processing is repeated.

  When the determination in step 114 is affirmed and the process proceeds to step 116, in this step 116, the ECU 86 and the driver 82 reversely rotate the output shaft 62 of the motor 60. The reverse rotation of the motor 60 is transmitted to the gear 74 of the clutch 72 via the gear 64, the gear 66, and the gear 70, and the gear 74 is rotated in the pull-out direction. That is, the gear 74 is rotated in synchronism with the rotation of the spool 20 in the pulling direction accompanying the pulling of the occupant's webbing 28. When the processing in step 116 is completed, the process proceeds to next step 118.

  In step 118, a value (T1-T2) obtained by subtracting the rotation time T2 in the pulling-out direction of the spool 20 from the energization time T1 for reversing the motor 60 becomes a predetermined value X set in advance. It is determined by the ECU 86 whether or not it has been exceeded. That is, in step 118, it is determined whether the gear 72 (the output shaft 62 of the motor 60) rotates relative to the adapter 76 (spool 20) by a predetermined amount to release the clutch 72. Only when the determination at step 118 is affirmative, the routine proceeds to the next step 120.

  In step 120, since it is detected that the clutch 72 has been released, the reverse rotation of the motor 60 is stopped by the ECU 86 and the driver 82. When the reverse rotation of the motor 60 is stopped, the process proceeds to the next step 122.

  In step 122, the ECU 86 determines whether or not the tongue plate provided on the webbing 28 is connected to the buckle device and the buckle switch 92 is turned on. That is, in this step 122, it is determined whether or not the occupant has remounted the webbing 28.

  If the determination at step 122 is affirmative, the drive control program is terminated at step 124. On the other hand, if the determination in step 122 is negative, the process returns to step 102 and the above-described processing is repeated.

  Here, in the motor retractor 10 according to the first embodiment of the present invention, as described above, while the webbing 28 is being wound by the normal rotation of the motor 60, the occupant tries to reattach the webbing 28. When pulled out, the binding current detection circuit 98 detects the binding current flowing through the motor 60 (step 114). In step 116, the motor 60 is rotated in the reverse direction to rotate the gear 74 in the drawing direction. In step 118, it is detected that the gear 74 is rotated by a predetermined amount relative to the adapter 76 (spool 20) to release the clutch 72, and thereafter, in step 120, the reverse rotation of the motor 60 is stopped. is there.

  Therefore, for example, when an occupant trying to reattach the webbing 28 pulls out the webbing 28 relatively quickly, that is, the rotation speed of the spool 20 in the pull-out direction is high, and the gear 74 moves in the pull-out direction with respect to the adapter 76. When the predetermined amount of relative rotation is not possible, the clutch 72 is kept connected, but the gear 74 rotates in synchronization with the spool 20, so that it is possible to prevent the webbing 28 from being uncomfortable or uncomfortable. . The spool 20 stops when the occupant has withdrawn the webbing 28. From this point, the motor 60 continues until the gear 74 further rotates a predetermined amount relative to the spool 20 in the pull-out direction and the clutch 72 is released. The reversal of is continued. Therefore, the clutch 72 is surely released after a predetermined time has elapsed since the time when the occupant canceled the withdrawal of the webbing 28.

  Further, for example, when an occupant trying to reattach the webbing 28 pulls out the webbing 28 relatively slowly, that is, the rotation speed of the spool 20 in the pull-out direction is slower than the rotation speed of the gear 74 in the pull-out direction. In this case (including the case where the passenger just holds the webbing 28 for a while), the gear 74 quickly rotates by a predetermined amount relative to the adapter 76 in the pull-out direction, so that the clutch 72 is immediately released. When the clutch 72 is released, the rotation of the motor 60 is stopped. In this state, the spool 20 can be freely rotated by releasing the clutch 72. Therefore, if the occupant subsequently pulls out the webbing 28, the occupant can smoothly pull out the webbing 28, and it is possible to suppress uncomfortable feeling and uncomfortable feeling in the pulling out of the webbing 28.

  As described above, in the motor retractor 10 according to the first embodiment of the present invention, the release of the clutch 72 is improved when the remounting operation is performed while the webbing 28 is being stored, and the webbing 28 is pulled out. It is possible to suppress the generation of discomfort and discomfort, and to ensure occupant non-compressibility when the webbing 28 is worn.

Moreover, in the motor retractor 10 according to the first embodiment of the present invention, whether or not the clutch 72 is released is determined based on the energization time of the motor 60 (rotation time of the output shaft 62) and the rotation time of the spool 20. Therefore, a special detection mechanism for detecting the release state of the clutch 72 is unnecessary, which is preferable.
<Second Embodiment>
Next, a second embodiment of the present invention will be described. In addition, about the structure and operation | movement fundamentally the same as the said 1st Embodiment, the same code | symbol as the said 1st Embodiment is attached | subjected and the description is abbreviate | omitted.

  FIG. 3 is a front sectional view showing the entire configuration of the motor retractor 200 according to the second embodiment of the present invention.

  As shown in FIG. 3, the motor retractor 200 has basically the same configuration as the motor retractor 10 according to the first embodiment described above, but is different from the ECU 86 according to the first embodiment. An ECU 202 is provided. The ECU 202 has basically the same configuration as the ECU 86 described above, but the ECU 202 stores a drive control program according to the second embodiment of the present invention.

  FIG. 4 shows a flowchart of the drive control program according to the second embodiment of the present invention. In addition, about the process similar to the drive control program which concerns on the said 1st Embodiment, the step number which concerns on the said 1st Embodiment is attached | subjected and the description is abbreviate | omitted.

  In the motor retractor 200 according to the second embodiment, when the tongue plate provided on the webbing 28 is released from the buckle device and the buckle switch 92 is turned off, the ECU 202 starts the drive control program (step 204). . Then, the process proceeds from step 102 to step 206 through step 106.

  In step 206, the ECU 202 determines whether or not the seating sensor 96 is on. That is, in step 206, after the occupant releases the wearing state of the webbing 28 and the webbing 28 is fully stored in the motor retractor 200, the ECU 202 determines whether or not the occupant exists in the vehicle compartment. If the determination in step 206 is affirmative, it is determined that there is a possibility that an occupant in the vehicle compartment will wear the webbing 28 again, and the routine proceeds to step 208. On the other hand, if the determination in step 206 is negative, it is determined that the occupant got out of the vehicle, and the routine proceeds to step 108.

  When the determination in step 206 is affirmed and the routine proceeds to step 208, in step 208, the ECU 202 and the driver 82 reverse the output shaft 62 of the motor 60, and the gear 74 is rotated in the pull-out direction. When the process in step 208 is completed, the process proceeds to the next step 210.

  In step 210, whether or not the energization time T1 to the motor 60 for rotating the motor 60 is longer than the energization time T0 to the motor 60 required to release the clutch 72 by a predetermined time β (T1). ≧ T0 + β) is determined by the ECU 86.

  In this case, during the energization time T0, the gear 74 rotates relative to the adapter 76 (spool 20) by a predetermined amount relative to the adapter 76 (spool 20) by the reverse rotation of the motor 60 when the clutch 72 is engaged and the spool 20 is stopped. The time required for releasing the clutch 72 is the same as the energization time for the motor 60 in step 110. That is, in step 210, the ECU 202 and the driver 82 determine whether or not the clutch 72 has been reliably released by reversing the motor 60 longer than the time T0 required to release the clutch 72. Only when the determination at step 210 is affirmed, the routine proceeds to the next step 212.

  In step 212, since it is detected that the clutch 72 has been released, the reverse rotation of the motor 60 is stopped by the ECU 202 and the driver 82. When the reverse rotation of the motor 60 is stopped, the process proceeds to the next step 214.

  In step 214, the ECU 202 determines whether or not the seating sensor 96 is on. That is, in step 214, after the clutch 72 is released and the motor 60 is stopped, it is determined by the ECU 202 whether or not an occupant is still present in the vehicle compartment. If the determination in step 214 is affirmed, the process proceeds to next step 216. On the other hand, if the determination in step 214 is negative, it is determined that the occupant got out of the vehicle, and the routine proceeds to step 218.

  If the determination in step 214 is affirmed and the process proceeds to step 216, in step 216, the ECU 202 determines whether or not the tongue plate provided on the webbing 28 is connected to the buckle device and the buckle switch 92 is turned on. To be judged. That is, in this step 216, it is determined whether or not the occupant has remounted the webbing 28.

  If the determination at step 216 is affirmative, the drive control program is terminated at step 224. On the other hand, if the determination in step 216 is negative, the process returns to step 214 and the above-described processing is repeated.

  On the other hand, if the determination in step 214 described above is denied and the process proceeds to step 218, it is detected in this step 218 that the occupant has got out of the vehicle, so the ECU 202 and the driver 82 control the output shaft 62 of the motor 60. Turn forward. For this reason, the spool 20 is rotated in the winding direction in the same manner as in step 102 described above. Thus, for example, even when the webbing 28 is pulled out from the motor retractor 200 due to the weight of the tongue plate, the vibration of the vehicle, or the like due to the release of the clutch 72 by the processing in step 208 to step 212 described above. The pulled out webbing 28 is taken up on the spool 20 again. When winding of the webbing 28 is started, the process proceeds to the next step 220.

  In step 220, the ECU 202 determines whether or not the rotation speed of the spool 20 has become 0 based on the detection signal from the spool rotation detection sensor 88. That is, in step 220, the ECU 202 determines whether or not the webbing 28 has been fully stored. Only when the determination at step 220 is affirmed, the routine proceeds to the next step 222.

  In step 222, since it is detected that the webbing 28 has been fully stored, the ECU 202 and the driver 82 stop the motor 60, and the winding operation of the webbing 28 is completed. In this step 222, the motor 60 remains connected to the spool 20 via the clutch 72 as in step 106 described above. As a result, the spool 20 is prevented from rotating and the wound webbing 28 is prevented from being pulled out of the spool 20. Accordingly, the webbing 28 is prevented from being pulled out of the motor retractor 10 due to the weight of the tongue plate, the vibration of the vehicle, and the like, and the appearance when the webbing 28 is not used can be prevented from deteriorating.

  When the process in step 222 is completed, the process proceeds to the next step 108 while the motor 60 remains connected to the spool 20 via the clutch 72, and the drive control program is terminated in step 224 via step 110. The

  Here, in the motor retractor 200 according to the second embodiment of the present invention, as described above, after the occupant releases the mounted state of the webbing 28 and the webbing 28 is stored by the normal rotation of the motor 60, the vehicle interior Is detected (step 206), the motor 60 is reversely rotated at step 208, and then the energization time T1 for reversing the motor 60 at step 210 is In this configuration, it is detected that the energization time T0 required for releasing the clutch 72 is longer than the energization time T0 by a predetermined time β, and then the reverse rotation of the motor 60 is stopped in step 212.

  Therefore, for example, when the passenger pulls out the webbing 28 in an attempt to remount the webbing 28 simultaneously with the reverse rotation of the motor 60 in step 208, that is, the gear 74 cannot rotate relative to the adapter 76 by a predetermined amount in the pull-out direction. Even when the coupled state of the clutch 72 is maintained, the gear 74 and the spool 20 rotate in synchronization with each other, so that it is possible to suppress uncomfortable feeling and uncomfortable feeling in the pulling out of the webbing 28. In addition, the ECU 202 and the driver 82 reverse the motor 60 by a predetermined time β longer than the energization time T0 required to release the clutch 72, so that the withdrawal of the webbing 28 by the occupant is eliminated and the spool After 20 (adapter 76) stops, gear 74 rotates relative to adapter 76 by a predetermined amount, and clutch 72 is released.

  As described above, in the motor retractor 200 according to the second embodiment of the present invention, the release of the clutch 72 is improved when the reattachment operation is performed after the webbing 28 is retracted, and the webbing 28 cannot be pulled out. It is possible to suppress the feeling of pleasure and discomfort and to ensure the occupant non-compressibility when the webbing 28 is worn.

  In the motor retractor 200 according to the second embodiment, the seat sensor 96 and the ECU 202 determine whether an occupant is present in the vehicle compartment. However, the present invention is not limited to this. For example, immediately after the buckle switch 92 is turned off, there is a high possibility that the occupant is present in the vehicle compartment. It is also possible for the ECU 202 to determine whether or not it exists. Also, for example, there is a high possibility that an occupant is present in the vehicle compartment immediately after the ignition switch of the vehicle is turned off. Therefore, if the ignition switch is connected to the ECU 202, the ECU 202 can determine whether there is an occupant in the vehicle compartment based on the elapsed time from when the ignition switch is turned off. Furthermore, in addition to the buckle switch 92 and the ignition switch described above, the ECU 202 can determine whether or not there is an occupant in the vehicle compartment by using switches operated by the occupant, the door opening / closing sensor 94, and the like. is there.

  In step 118 of the drive control program according to the second embodiment, the energization time T1 to the motor 60 is longer than the energization time T0 to the motor 60 necessary for releasing the clutch ( (T1−T2 ≧ X = T0 + α), instead of the process in step 210, a process similar to that in step 118 may be performed.

1 is a front cross-sectional view showing an outline of the overall configuration of a motor retractor according to a first embodiment of the present invention. It is a flowchart which shows the control procedure of the control means of the motor retractor which concerns on the 1st Embodiment of this invention. It is front sectional drawing which shows the outline of the whole structure of the motor retractor which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the control procedure of the control means of the motor retractor which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

10 motor retractor 20 take-up shaft 28 webbing 34 spiral spring (biasing member)
60 Motor 62 Output shaft 72 Clutch 82 Driver (control means)
86 ECU (control means)
88 Spool rotation detection sensor (control means)
92 Buckle switch (control means)
96 Seating sensor (control means)
98 Restraint current detection circuit (control means)

Claims (3)

A long belt-like webbing that restrains the occupant's body in a state of being attached to the occupant seated on the vehicle seat;
A winding shaft on which the base end side in the longitudinal direction of the webbing is locked, and the webbing is wound so as to be able to be wound and pulled out;
A biasing member connected to the winding shaft and biasing the winding shaft in the webbing winding direction with a biasing force corresponding to occupant non-compressibility in the mounted state of the webbing;
A motor,
The motor is interposed between the winding shaft and the output shaft of the motor, transmits the normal rotation of the motor to the winding shaft, rotates the winding shaft in the webbing winding direction, and reverses the motor. A clutch that is released by a predetermined amount of relative rotation between the output shaft and the winding shaft,
When an occupant pulls out the webbing during winding of the webbing due to normal rotation of the motor and an external force acting against the winding of the webbing acts to detect a restraining current flowing through the motor, the motor is reversed. And after that, the output shaft rotates at least the predetermined amount relative to the take-up shaft and continues the reverse rotation of the motor until the clutch is released, and
Motor retractor with The control means determines whether or not the clutch is released based on each rotation time of the output shaft and the winding shaft,
The motor retractor according to claim 1. A long belt-like webbing that restrains the occupant's body in a state of being attached to the occupant seated on the vehicle seat;
A winding shaft on which the base end side in the longitudinal direction of the webbing is locked, and the webbing is wound so as to be able to be wound and pulled out;
A biasing member connected to the winding shaft and biasing the winding shaft in the webbing winding direction with a biasing force corresponding to occupant non-compressibility in the mounted state of the webbing;
A motor,
It is interposed between the winding shaft and the output shaft of the motor, transmits normal rotation of the motor to the winding shaft, rotates the winding shaft in the webbing winding direction, and stores the webbing. A clutch that maintains a connected state of the output shaft and the winding shaft in a state;
When the occupant is on the webbing when the occupant gets on, the output shaft and the take-up shaft are rotated relative to each other by a predetermined amount to reverse the motor, thereby releasing the clutch. Control means for reversing the motor longer than the predetermined time when the occupant is present in the vehicle compartment after the occupant releases the webbing and the webbing is stored;
Motor retractor with

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