JP2006015916A - Motor retractor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a motor retractor capable of eliminating winding slack to a winding shaft of webbing in a normal wearing state without giving a discomfort such as an oppressive feeling to an occupant, and improving occupant restraining performance. <P>SOLUTION: In the motor retractor 10, when an occupant wears the webbing 28, while a middle portion of the webbing 28 is clipped by a pair of clamps 47, 48 at an outlet portion form the motor retractor 10 of the webbing 28, a motor 60 is rotated at high torque to wind up the webbing 28 to a spool 20 at a high load, and slack of a layered part 29 is eliminated. Then, holding of the webbing 28 by the pair of the clamps 47, 48 is released after stopping the motor 60. In this state, the layered part 29 of the webbing 28 is held by interlayer friction applied thereon, so that the reoccurrence of the slack is suppressed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a motor retractor that can wind up an occupant-constrained webbing by rotating a winding 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 side by rotating the webbing in the longitudinal direction, and a spiral spring that biases the winding shaft in the webbing winding direction. And the like. In the seat belt device provided with the retractor, when the webbing is mounted, the occupant pulls out the webbing against the urging force of the urging member, and engages the tongue plate provided on the webbing with the buckle device. The webbing is attached.

  By the way, in the webbing in a normal wearing state, slack occurs due to sliding resistance between clothes, tongue plates and the like worn by the occupant and the webbing, thickness of the clothes, interlayer friction of the webbing wound around the winding shaft, and the like. . These slacks in webbing affect the occupant restraint during sudden deceleration of the vehicle, so it is desirable to remove them all. On the other hand, to ensure the comfort of the occupant wearing the webbing, it is necessary to reduce the biasing force of the biasing member as much as possible. When the webbing is released, the webbing is loosened without being wound around the winding shaft until the end, and there is a contradictory problem that the appearance when the webbing is not used deteriorates.

  On the other hand, a motor retractor capable of winding a webbing by rotating a winding shaft by a driving force of a motor has been proposed (for example, see Patent Document 1). In such a motor retractor, it is possible to assist the winding of the webbing when releasing the webbing by the driving force of the motor, so the urging force of the urging member is reduced and the occupant in the normal webbing wearing state is reduced. The webbing can be reliably wound and stored on the winding shaft even when the webbing is released.

Here, in the case of such a motor retractor, it is conceivable to remove the slack of the webbing in the normal webbing wearing state by using the winding function of the motor. However, to reduce the occupant restraint due to the slack of the webbing, the slack of the webbing generated around the take-up shaft due to interlayer friction of the webbing is an important factor. Since it is necessary to rotate the winding shaft with a large winding load by the motor, this inevitably gives the passenger an uncomfortable feeling such as a feeling of pressure.
JP 2001-163186 A

  In consideration of the above facts, the present invention can remove the slack of the webbing from the winding shaft in the normal wearing state without giving the passenger an uncomfortable feeling such as a feeling of pressure, thereby improving the occupant restraint. The purpose is to obtain.

  In the motor retractor according to the first aspect of the present invention, a long belt-like webbing that restrains the occupant's body while being attached to the occupant seated in a vehicle seat, and a longitudinal base end portion of the webbing are locked. The webbing is wound in layers so that the webbing can be taken out, and the webbing shaft is always urged in the webbing winding direction, and the webbing is connected to the winding shaft, and the webbing is driven by the driving force. A motor that rotates in the winding direction; and a webbing intermediate portion that is provided on the occupant side of the webbing on the winding shaft and on the way to the occupant than the layered portion of the webbing. The holding means that can be held and held, and after the webbing of the occupant is mounted, the holding means is operated to hold and hold the webbing, and then the motor is rotated to The shaft is characterized by comprising a control means for removing the slack of the layered portion of the webbing by rotating to the webbing take-up direction.

  In the motor retractor according to claim 1, the occupant-constrained webbing is provided in a layered manner so that the webbing for occupant restraint can be wound and withdrawn, and the winding shaft is always urged in the webbing winding direction. It is rotated in the webbing take-up direction by the driving force from the motor. Further, in this motor retractor, when the occupant is wearing the webbing, the layer is a portion of the webbing wound around the take-up shaft (hereinafter simply referred to as “the layered portion of the webbing”) and on the way to the occupant. Provided in correspondence with the webbing intermediate portion, and holding means capable of holding and holding the webbing, and control means for controlling the operation of the holding means and the motor.

  Here, in this motor retractor, after the occupant wears the webbing, the control unit operates the clamping unit to clamp and hold the webbing, and then rotates the motor to move the winding shaft in the webbing winding direction. Rotate. For this reason, the portion closer to the winding shaft than the webbing pinching means is tightened between the winding shaft and the pinching means, and the layered portion of the webbing wound around the winding shaft is wound onto the winding shaft. . Thereby, the slack (winding slack) of the layered portion of the webbing is removed, and the occupant restraint property is improved.

  In addition, in this case, the clamping means holds and holds the intermediate webbing portion on the occupant side of the webbing and on the way to the occupant. The take-up load of the take-up shaft does not act, thereby preventing the passenger from feeling uncomfortable such as a feeling of pressure.

  As described above, in the motor retractor according to the first aspect, the slack of the webbing on the winding shaft in the normal wearing state can be removed without giving the passenger an uncomfortable feeling such as a feeling of pressure. improves.

  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 stops the motor after removing the slack of the layered portion of the webbing, and then the clamping means The holding of the webbing is released.

  In the motor retractor according to the second aspect, after removing the slack of the layered portion of the webbing, the control unit stops the motor and then releases the holding of the webbing by the clamping unit. In this state, since the layered portion of the webbing is held by the interlayer friction acting on itself, the reoccurrence of slack is suppressed. This prevents, for example, the webbing from unnecessarily extending due to the inertial force of the occupant acting on the webbing while the winding shaft is locked during sudden deceleration of the vehicle, and the webbing is tightened and the occupant restraint is prevented. Improves.

  Moreover, in order to remove the slack of the webbing layer-like portion that has an important effect on the occupant restraint as described above by the winding function of the motor, the urging force that urges the winding shaft in the direction of winding the webbing is not applied to the occupant. It is possible to set the strength corresponding to the characteristics, and to ensure the comfort of the passenger.

  The motor retractor of the invention according to claim 3 is the motor retractor according to claim 2, wherein the control means releases the holding of the webbing by the clamping means, and then the webbing is pulled out by a predetermined amount or more. When slack occurs in the webbing again, the clamping means is operated to clamp and hold the webbing, and then the motor is rotated to rotate the winding shaft in the webbing winding direction. Then, the slack of the layered portion of the webbing is removed, and then the motor is stopped and then the holding of the webbing by the clamping means is released.

  In the motor retractor according to claim 3, the control means releases the webbing held by the clamping means, and then the webbing is pulled out by a predetermined amount or more due to, for example, movement of the occupant to the front of the vehicle, so that the slack in the webbing is regenerated. In this case, the holding means is operated to hold and hold the webbing, and then the motor is rotated to rotate the winding shaft in the webbing winding direction. As a result, the slack that has reappeared in the layered portion of the webbing is removed without causing the passenger to feel uncomfortable feeling such as pressure. After that, the control means stops the motor and then releases the holding of the webbing by the clamping means. In this state, the layered portion of the webbing is held by interlayer friction acting on itself, so that the occurrence of slack is suppressed and the occupant restraint is improved again.

  The motor retractor according to a fourth aspect of the present invention is the motor retractor according to any one of the first to third aspects, wherein the control means is configured to perform the webbing of the webbing by the clamping means after the webbing of the occupant is mounted. The motor is rotated in a state in which the holding is released to rotate the winding shaft in the webbing winding direction to remove the slack of the portion on the occupant side of the layered portion of the webbing, and then the motor It is characterized by stopping.

  In the motor retractor according to the fourth aspect, after the occupant wears the webbing, the control unit rotates the motor in a state in which the holding of the webbing by the clamping unit is released to rotate the winding shaft in the webbing winding direction. In this case, for example, if the take-up shaft is rotated in the webbing take-up direction with a low torque by rotating the motor at a low torque, the portion on the occupant side of the webbing is loosened, that is, worn by the occupant The loosening of the webbing that can be removed relatively easily caused by the sliding resistance between the clothing and the webbing to be worn and the thickness of the clothing is removed without causing the passengers to feel uncomfortable feeling such as pressure. And a control means stops a motor, after removing the slack of a passenger | crew side part rather than the layered part of webbing in this way. Thereby, the slack of the webbing during normal wearing is reduced, and the occupant restraint is improved.

  The removal of the slack in the occupant side of the webbing layered portion in the motor retractor according to claim 4 is performed by removing the slack in the layered webbing portion in the motor retractor according to any one of claims 1 to 3. It may be performed either before or after removal. In any case, it is possible to minimize the slack in the entire longitudinal direction of the webbing during normal wearing by removing the slack in the above two steps. Thus, for example, the function of a so-called “pretensioner” that improves the occupant restraint performance in the event of a vehicle collision is obtained by rotating the winding shaft with the explosive force of gunpowder and winding the webbing on the winding shaft by a certain amount. It is also possible to perform only by winding the webbing with the driving force.

  A motor retractor according to a fifth aspect of the present invention is the motor retractor according to the fourth aspect, wherein the control means removes the slack of the occupant side portion of the webbing from the layered portion and stops the motor. Later, when the webbing is pulled out by a predetermined amount or more and slackness occurs again in the webbing, the motor is rotated in a state where the holding of the webbing by the clamping means is released, and the winding shaft is The webbing is rotated in the webbing winding direction to remove slack from the occupant side of the layered portion of the webbing, and then the motor is stopped.

  In the motor retractor according to the fifth aspect, after the control means removes the slack of the portion on the occupant side of the layered portion of the webbing and stops the motor, the webbing is performed by, for example, moving the occupant forward of the vehicle. When the webbing is pulled out more than the fixed amount and slackness is generated again, the motor is rotated in a state where the holding of the webbing by the clamping means is released, and the winding shaft is rotated in the webbing winding direction. In this case, for example, if the motor is rotated at a low torque, the slack that has reoccurred in the occupant side relative to the layered portion of the webbing is removed without causing discomfort such as a feeling of pressure to the occupant, and the occupant is restrained again. Improves. Thereafter, the control means stops the motor.

  A motor retractor according to a sixth aspect of the present invention is the motor retractor according to any one of the first to fifth aspects, wherein the clamping means are provided opposite to both surfaces of the webbing and around the support shaft. The webbing can be moved toward and away from the webbing by rotating the webbing. The webbing is sandwiched and held when approaching the webbing, and the holding of the webbing is released when the webbing is separated from the webbing. A pair of clamps and a solenoid that reciprocates a plunger connected to the pair of clamps to move the pair of clamps toward and away from the webbing.

  In the motor retractor according to the sixth aspect, a pair of clamps are provided corresponding to the webbing intermediate portion on the occupant side with respect to the layered portion of the webbing and on the way to the occupant. The pair of clamps are provided on both sides of the webbing so as to face each other, and can move toward and away from the webbing by rotating around the support shaft. A solenoid plunger is connected to the pair of clamps, and when the solenoid plunger reciprocates, the pair of clamps move toward and away from the webbing. In this case, when the pair of clamps are close to the webbing, the webbing is sandwiched and held by the pair of clamps. Further, when the pair of clamps are separated from the webbing, the webbing is released from being held by the pair of clamps. Thereby, a clamping means can be made into a simple structure.

  As described above, in the motor retractor according to the present invention, the slack of the webbing on the winding shaft in the normal wearing state can be removed without giving the passenger an uncomfortable feeling such as a feeling of pressure. improves.

  FIG. 1 is a front sectional view showing the overall configuration of a motor retractor 10 according to an 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 from the base end side in a layered manner (hereinafter, a portion of the webbing 28 wound around the spool body 22 is referred to as a “layered portion 29”). 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 present 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 ratchet hole in the leg piece 18. It is configured to mesh with the 36 internal teeth and prevent rotation of the spool 20 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 the 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, and the output shaft 62 of the motor 60 is positive. When rotating in the 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, a pair of clamps 47 and 48 formed in a cylindrical shape having an elliptical cross section are provided on the opposite side of the motor 60 via the spool 20 (see FIG. 2). The pair of clamps 47 and 48 are arranged in parallel to the spool 20 at the exit portion of the webbing 28 from the motor retractor 10 (in FIG. 1, on the upper end side of the frame 12 and between the side wall 16 and the side wall 18). The webbing 28 faces each of both surfaces.

  At the end of the clamp 47 on the spool 20 side (the lower end in FIGS. 1 and 2), a cylindrical support shaft 49 places the clamp 47 in the axial direction (left and right in FIG. 1 and on the paper in FIG. 2). A cylindrical support shaft 50 similarly holds the clamp 48 at the end of the clamp 48 on the spool 20 side (the lower end in FIGS. 1 and 2). It penetrates along the axial direction. One end of each support shaft 49, 50 in the axial direction (the right end in FIG. 1) is rotatably supported by the side wall 18 of the frame 12, and the other end of each support shaft 49, 50 in the respective axial direction. The portion (the left end portion in FIG. 1) is rotatably supported on the side wall 16 of the frame 12. Accordingly, the clamps 47 and 48 can be rotated around the support shafts 49 and 50, respectively, and can be moved toward and away from the webbing 28 by rotating around the support shafts 49 and 50. ing.

  Further, a plate-like connecting piece 51 is integrally protruded along the radial direction of the clamp 47 at one axial end portion of the clamp 47 (right end portion in FIG. 1). Similarly, at one end (the right end in FIG. 1), a plate-like connecting piece 52 is integrally projected along the radial direction of the clamp 48. The connecting piece 51 and the connecting piece 52 are arranged offset in the axial direction of the respective clamps 47 and 48 and overlap each other in the plate thickness direction.

  The connecting piece 51 is formed with a long hole 53 that penetrates in the plate thickness direction, and the connecting piece 52 is similarly formed with a long hole 54 that penetrates in the plate thickness direction. The long holes 53 and 54 correspond to the plunger 56 of the solenoid 55 in which the main body 57 is fixed to the side wall 18 of the frame 12. The solenoid 55 is of a so-called “pull type”, and as shown in FIG. 3, the intermediate portion in the longitudinal direction of the plunger 56 is bent at a right angle. The distal end of the plunger 56 is slidably inserted into the long holes 53 and 54 of the connecting pieces 51 and 52.

  Here, in the motor retractor 10, the plunger 56 reciprocates depending on whether power is supplied to the solenoid 55, so that the pair of clamps 47 and 48 are moved toward and away from the webbing 28 via the connecting pieces 51 and 52. It is supposed to be. That is, when the solenoid 55 is not energized, the plunger 56 is pulled out from the main body 57 of the solenoid 55 by a predetermined amount, and in this state, as shown in FIG. The webbing 28 is separated. On the other hand, when the solenoid 55 is energized, the plunger 56 is pulled by a predetermined amount toward the main body 57 side of the solenoid 55 (the lower side in FIGS. 1 and 2), and as shown in FIG. The clamps 47 and 48 are close to the webbing 28. In addition, when the pair of clamps 47 and 48 are close to the webbing 28 as described above, the pair of clamps 47 and 48 sandwich and hold the webbing 28. 4A and 4B, illustration of the solenoid 55 excluding the tip of the plunger 56 is omitted for convenience of explanation.

  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 predetermined webbing attachment control program. 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 this case, the ECU 86 and the driver 82 control the magnitude of the current supplied to the motor 60, so that the rotational torque of the output shaft 62 of the motor 60 (based on the winding force of the webbing 28) can be made non-compressible. It can be adjusted from a corresponding low torque to a high torque corresponding to winding of a heavy load. In this case, the ECU 86 can store the energization time to the motor 60.

  Further, a solenoid 55 is electrically connected to the driver 82, and the ECU 86 controls whether or not power is supplied to the solenoid 55 via the driver 82.

  In addition, a spool rotation detection sensor 88 (in this embodiment, a magnetic sensor) is connected to the ECU 86. 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 is configured to detect the rotation amount of the spool 20 based on the detection signal output from the spool rotation detection sensor 88.

  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 connected 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.

  Further, a door opening / closing sensor 94 and a seating sensor 96 are connected to the ECU 86, respectively. 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.

  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”).

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

  In the motor retractor 10 configured as described above, when the ECU 86, the door opening / closing sensor 94, and the seating sensor 96 detect a mounting preparation state in which the occupant intends to mount the webbing 28 (step 100), in step 102, the ECU 86 and the driver 82 Reverses the motor 60 to release the clutch 72. As a result, the spool 20 can rotate, and the occupant can pull out the webbing 28. Next, the routine proceeds to step 104.

  In step 104, the ECU 86 determines whether the occupant connects the tongue plate provided on the webbing 28 to the buckle device and the buckle switch 92 is turned on. The process proceeds to the next step 106 only when this determination is affirmed.

  In step 106, since it is detected that the occupant wears the webbing 28, the ECU 86 and the driver 82 cause the output shaft 62 of the motor 60 to rotate normally with a low torque. The low torque 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 with low torque. In this case, since the webbing 28 is wound around the spool 20 with a low load, the portion of the webbing 28 closer to the occupant side than the layered portion 29, that is, the sliding resistance between the garment or tongue plate worn by the occupant and the webbing 28. , And the slack of the webbing 28 that can be removed relatively easily caused by the thickness of the garment.

  In addition, in this case, since the webbing 28 is wound around the spool 20 with a low load, it is possible to prevent the passenger from feeling uncomfortable such as a feeling of pressure. When the processing at step 106 is completed, the routine proceeds to the next step 108.

  In step 108, the ECU 86 determines whether or not a lock detection signal is output from the restraint current detection circuit 98. Only when this determination is affirmed, the process proceeds to the next step 110.

  In step 110, since it is detected that a restraint current has flowed through the motor 60, the ECU 86 and the driver 82 stop the normal rotation of the motor 60. At this point, the clutch 72 is kept connected. When the processing at step 110 is completed, the routine proceeds to the next step 112.

  In step 112, the ECU 86 and the driver 82 start supplying power to the solenoid 55. For this reason, the plunger 56 is retracted by a predetermined amount toward the main body 57 side of the solenoid 55, and the pair of clamps 47 and 48 are moved closer to the webbing 28 via the connecting pieces 51 and 52. As a result, the webbing 28 is held by the pair of clamps 47 and 48 at the exit from the motor retractor 10. When the processing in step 112 is completed, the process proceeds to next step 114.

  In step 114, the ECU 86 and the driver 82 cause the output shaft 62 of the motor 60 to rotate forward with high torque. The high-torque forward rotation of the motor 60 is transmitted to the spool 20 via the gear 64, the gear 66, the gear 70, and the clutch 72, and the spool 20 is rotated with high torque in the winding direction. In this case, since the webbing 28 is sandwiched and held by the pair of clamps 47 and 48 at the exit portion from the motor retractor 10, the portion of the webbing 28 closer to the spool 20 than the pair of clamps 47 and 48 is the spool. The layered portion 29 of the webbing 28 wound around the spool 20 and tightened between the clamp 20 and the pair of clamps 47 and 48 is wound around the spool 20. Thereby, the slack of the layered portion 29 of the webbing 28 that has an important effect on the occupant restraint property is removed, and the occupant restraint property is improved (the winding speed of the webbing 28 at the high torque is, for example, 0, 1 to 0,3 m / s is sufficient, and the winding time is a few seconds.

  In addition, in this case, the pair of clamps 47 and 48 is the intermediate portion of the webbing 28 corresponding to the exit portion of the webbing 28 from the motor retractor 10 (on the passenger side of the layered portion 29 of the webbing 28 and on the way to the passenger). The intermediate portion of the webbing 28 is sandwiched and held, so that the winding load of the spool 20 does not act on the occupant side portion of the pair of clamps 47 and 48 of the webbing 28, thereby compressing the occupant. An unpleasant feeling such as feeling is prevented. When the processing in step 114 is completed, the process proceeds to next step 116.

  In step 116, the ECU 86 determines whether or not a predetermined time has elapsed since the start of energization of the motor 60 in step 114. That is, in this step 116, it is determined whether or not the slack of the layered portion 29 of the webbing 28 has been reliably removed. The process proceeds to the next step 118 only when this determination is affirmed.

  In step 118, the ECU 86 and the driver 82 stop the motor 60 and then reverse the output shaft 62 by a predetermined amount to release the clutch 72. Next, the routine proceeds to step 120.

  In step 120, the ECU 86 and the driver 82 cut off the power supply to the solenoid 55. For this reason, the plunger 56 of the solenoid 55 is pulled out from the main body 57 by a predetermined amount, and the pair of clamps 47 and 48 are moved away from the webbing 28 via the connecting pieces 51 and 52. As a result, the holding of the webbing 28 by the pair of clamps 47 and 48 is released.

  In this state, since the layered portion 29 of the webbing 28 is held by interlayer friction acting on itself, the occurrence of slack in the layered portion 29 is suppressed. Therefore, when the vehicle suddenly decelerates, the occupant's inertial force acts on the webbing 28 in a state where the rotation of the spool 20 in the pull-out direction is prevented by the lock mechanism 38, and the layered portion 29 of the webbing 28 is wound and tightened. In addition to the removal of the slack in the portion closer to the passenger than the layered portion 29 of the webbing 28 due to the winding of the low load in step 106 described above, the longitudinal direction of the webbing 28 during normal wearing Sag across the direction is minimized. Thereby, a passenger | crew restraint property improves markedly.

  In this state, the spool 20 is urged in the winding direction of the webbing 28 by the spiral spring 34, but the biasing force of the spiral spring 34 (based on the winding force of the webbing 28) is incompressible to the occupant. Since it has the corresponding strength, the occupant wearing the webbing 28 is not given a feeling of pressure. Thereby, the passenger | crew's comfort in the normal webbing 28 mounting state can also be ensured.

  When the process in step 120 is completed, the process proceeds to the next step 122.

  In step 122, the ECU 86 determines whether or not the spool rotation detection sensor 88 has detected that the spool 20 has rotated a predetermined amount or more in the pull-out direction. That is, in this step 122, it is determined whether or not the webbing 28 has been pulled out by a predetermined amount or more due to the movement of the occupant forward of the vehicle or the like, and slack has occurred in the webbing 28 again.

  If the determination in step 122 is affirmed, it is determined that slack has occurred in the webbing 28, and the process returns to step 106 to repeat the above-described processing. On the other hand, if the determination in step 122 is negative, the process proceeds to the next step 124 and the webbing attachment control program is terminated.

  As described above, in the motor retractor 10 according to the embodiment of the present invention, the slack of the webbing 28 in the normal wearing state can be minimized without causing discomfort such as a feeling of pressure to the occupant. improves.

  In addition, since the slack of the webbing 28 in the normal wearing state can be minimized in this manner, for example, the winding shaft is generally rotated by the explosive force of the explosive, and the webbing is wound around the winding shaft by a certain amount and the vehicle is in a collision state. The so-called “pretensioner” function for improving the occupant restraint function can be performed only by winding the webbing 28 by the driving force of the motor 60.

  Furthermore, in the motor retractor 10 according to the embodiment of the present invention, the pair of clamps 47 and 48 are moved toward and away from the webbing 28 by the driving force of the solenoid 55 to easily hold and release the webbing 28. Therefore, the apparatus can be simplified, which is preferable.

  In the above embodiment, the slack of the layered portion 29 is removed after removing the slack of the portion closer to the passenger than the layered portion 29 of the webbing 28. However, the present invention is not limited to this, and the slack of the layered portion 29 is not limited thereto. It is also possible to remove the slack in the portion closer to the passenger than the layered portion 29 of the webbing 28 after removing the webbing 28.

It is a front sectional view showing the outline of the whole composition of the motor retractor concerning an embodiment of the invention. It is a side view which shows the structure of the peripheral member containing the clamping means which is a structural member of the motor retractor which concerns on embodiment of this invention. It is a perspective view which shows the structure of the clamping means which is a structural member of the motor retractor which concerns on embodiment of this invention. The structure of the clamping means which is a structural member of the motor retractor which concerns on embodiment of this invention is shown, (A) is a side view which shows the state from which holding | maintenance of the webbing by the clamping means was cancelled | released, (B) is clamping means It is a side view which shows the state by which webbing was hold | maintained. It is a flowchart which shows the control procedure of the control means of the motor retractor which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Motor retractor 20 Winding shaft 28 Webbing 29 Layered part 47, 48 A pair of clamp (clamping means)
49, 50 Support shaft (clamping means)
55 Solenoid (clamping means)
56 Plunger 60 Motor 82 Driver (control means)
86 ECU (control means)
92 Buckle switch (control means)
98 Restraint current detection circuit (control means)

Claims (6)

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;
The webbing is locked in the longitudinal direction proximal end, the webbing is wound in a layered manner so that the webbing can be pulled out, and a winding shaft always biased in the webbing winding direction;
A motor connected to the take-up shaft and rotating the take-up shaft in the webbing take-up direction with a driving force;
Clamping means provided on the occupant side of the webbing to the take-up shaft and corresponding to the webbing intermediate part in the middle of the webbing and capable of clamping and holding the webbing; ,
After the webbing of the occupant is mounted, the clamping means is operated to clamp and hold the webbing, and then the motor is rotated to rotate the winding shaft in the webbing winding direction. Control means for removing slack in the layered portion;
Motor retractor with The control means includes
After removing the slack of the layered portion of the webbing, stopping the motor and then releasing the holding of the webbing by the clamping means;
The motor retractor according to claim 1. The control means includes
After releasing the holding of the webbing by the clamping means, if the webbing is pulled out more than a predetermined amount and slackness occurs again in the webbing, the clamping means is operated to hold and hold the webbing. After that, by rotating the motor and rotating the winding shaft in the webbing winding direction, the slack of the layered portion of the webbing is removed, and then the motor is stopped and then the motor is stopped. Releasing the holding of the webbing by the clamping means;
The motor retractor according to claim 2. The control means includes
After mounting the webbing of the occupant, the motor is rotated in a state in which the holding of the webbing by the clamping means is released to rotate the winding shaft in the webbing winding direction, and from the layered portion of the webbing Also remove the slack in the passenger side, and then stop the motor,
The motor retractor according to any one of claims 1 to 3, wherein the motor retractor is provided. The control means includes
If the webbing is pulled out more than a predetermined amount after the sag of the occupant side of the webbing is removed and the motor is stopped, and the webbing is loosened again, the clamping With the webbing held by the means released, the motor is rotated to rotate the take-up shaft in the webbing take-up direction, thereby removing slack in the occupant side portion of the webbing from the layered portion. And then stop the motor,
The motor retractor according to claim 4. The clamping means is
The webbing is provided opposite to both surfaces of the webbing, and can be moved toward and away from the webbing by rotating around a support shaft. The webbing is sandwiched and held in a state of approaching the webbing. A pair of clamps for releasing the holding of the webbing in a state separated from the webbing;
A solenoid that reciprocally moves a plunger connected to the pair of clamps to move the pair of clamps toward and away from the webbing;
The motor retractor according to any one of claims 1 to 5, further comprising:

Images