JP5203881B2 - Webbing take-up device - Google Patents

Description

  The present invention relates to a webbing take-up device that winds and stores a webbing belt constituting a seat belt device of a vehicle.

  As an example, in a webbing take-up device as disclosed in Patent Document 1 below, a torsion shaft is provided inside a spool for taking up a webbing belt. The torsion shaft is connected to the spool at an intermediate portion in the axial direction of the spool. Locking mechanisms are provided on both sides of the spool in the axial direction so as to restrict the rotation of the end of the engaged torsion shaft by directly or indirectly engaging the end of the torsion shaft.

  For example, when the vehicle suddenly decelerates, the end of the torsion shaft is locked to the lock mechanism, and in this state, the occupant's body trying to move inertially toward the front of the vehicle pulls the webbing belt and the spool torque is generated. However, if the mechanical strength of the torsion shaft is exceeded, torsional deformation occurs in the torsion shaft. Since the spool can rotate in the direction of pulling out the webbing belt by the amount of torsional deformation on this torsion shaft, the webbing belt is pulled out from the spool by this allowable rotation amount, and the occupant is pulled by the allowable pull-out length from the spool of this webbing belt. It can move to the front side of the vehicle. Further, as described above, a part of the energy of the force with which the occupant pulls the webbing belt is consumed as energy to be used for torsional deformation of the torsion shaft, and this consumed energy is absorbed.

  Further, in the configuration disclosed in Patent Document 1, driving means such as a solenoid or a gas generator is used to activate the other lock mechanism, and the timing of this driving means is controlled by a control means such as an ECU. One lock mechanism can be operated with a delay relative to the other lock mechanism. For this reason, one of the lock mechanisms is operated, and further, the other lock mechanism is operated after the torsional deformation occurs on the side held by the one lock mechanism above the connecting portion with the spool of the torsion shaft. Then, the torsional deformation is delayed on the other side of the connecting portion with the spool of the torsion shaft. Thereby, the amount of energy absorbed by deformation of the torsion shaft can be increased stepwise.

In addition, a sensor that detects the occupant's physique based on the load acting on the seat is connected to the control means. For example, when the occupant is relatively small, the driving means is not driven based on a signal from the sensor. Thus, the control means controls so that the torsional deformation can be prevented from occurring on the other side of the connecting portion of the torsion shaft with the spool. As a result, when the occupant is small, the amount of energy absorbed by the torsion shaft is not increased stepwise.
US Patent No. 5,799,893

  However, in order to activate the other locking mechanism, driving means such as a solenoid and a gas generator are used, and furthermore, a control means for controlling the driving means and a sensor for detecting the physique of the occupant are provided. This complicates the configuration and increases the cost.

  In consideration of the above facts, the present invention provides a webbing take-up device that can change the amount of energy absorption with a relatively simple configuration and that can change the total energy absorbed according to the physique of the occupant. The purpose is to obtain.

In the webbing take-up device according to the first aspect of the present invention, the longitudinal base end side of the long belt-like webbing belt is locked, and the webbing belt is rotated by rotation in the winding direction which is one of the axes. The spool is wound and stored from the base end side in the longitudinal direction, and when the webbing belt is pulled toward the tip end side, a spool to which a rotational force in the pulling direction opposite to the winding direction is applied, and the spool can rotate together with the spool. A first energy absorbing means provided on the spool and deformed by applying a rotational force exceeding its own mechanical strength to the spool in a state in which the rotation in the pull-out direction is restricted; Rotation of the first energy absorbing means in the withdrawal direction in at least one of a deceleration state and a state in which the spool is rotated at a predetermined speed or more in the withdrawal direction The first locking means for regulating and the spool are rotatably provided together with the spool, and a rotational force exceeding its own mechanical strength is applied to the spool in a state where the rotation in the pull-out direction is regulated. And the second energy absorbing means deformed at the same time as the predetermined speed at which the first locking means operates in a state where the restriction of operation has been canceled or at a speed different from the predetermined speed in the pull-out direction. A second locking means for restricting rotation of the second energy absorbing means in the pull-out direction by rotation of the spool; and restricting the operation of the second locking means by interfering with the second locking means; The first locking means is operated in conjunction with the rotation of the spool in the pull-out direction in the rotation-restricted state of the first energy absorbing means in the pull-out direction. And, the spool is provided with a regulating means for eliminating interference on the second locking means by a predetermined angle to the pull-out direction.

  In the webbing take-up device according to the first aspect of the present invention, the first locking means is actuated when at least one of the vehicle sudden deceleration state or the spool rotates in the pull-out direction at a predetermined speed or higher. . When the first lock means is activated, the rotation of the first energy means in the pull-out direction is restricted. Since the first energy absorbing means can be rotated together with the spool, the rotation of the first energy absorbing means in the pull-out direction is restricted by the first lock means, thereby indirectly restricting the rotation of the spool in the pull-out direction. Is done.

  As a result, the withdrawal of the webbing belt from the spool is restricted, and the body of the passenger wearing the webbing belt is strongly restrained by the webbing belt.

  As described above, in the state where the rotation of the first energy absorbing means in the pulling direction is restricted, the rotational force in the pulling direction generated in the spool by the occupant pulling the webbing belt causes the above described first energy absorbing means. If the mechanical strength is exceeded, the first energy absorbing means is deformed. The spool can rotate in the pull-out direction by the amount of deformation of the first energy absorbing means, the webbing belt is pulled out from the spool by the amount of rotation of the spool in the pull-out direction, and energy used for deformation of the first energy absorbing means is obtained. Absorbed.

  On the other hand, the webbing take-up device according to the present invention is provided with the second locking means in addition to the first locking means, but the second locking means is interfered with the regulating means, and the second locking means In the interference state of the restricting means, the operation of the second lock means is restricted.

  When the spool rotates by a predetermined angle in the pull-out direction with the deformation of the first energy absorbing means described above, the interference of the restricting means with respect to the second locking means is canceled in conjunction with this. In this state, when the spool rotates in the pull-out direction at the same speed as the predetermined speed at which the first lock means operates or a speed different from the predetermined speed, the second lock means moves the second energy absorbing means in the pull-out direction. Rotation is regulated. The second energy absorbing means can rotate together with the spool, and in this state, the rotation of the first lock base in the pull-out direction of the first lock base is already restricted. Therefore, in this state, if the rotational force in the pulling-out direction of the spool exceeds the sum of the mechanical strength of the first energy absorbing means and the mechanical strength of the second energy absorbing means, the first energy absorbing means Then, further deformation occurs, and further deformation occurs in the second energy absorbing means.

  Therefore, in this state, the spool can rotate in the pull-out direction by the amount of deformation of the first energy absorbing unit and the second energy absorbing unit, and the webbing belt is pulled out from the spool by the amount of rotation of the spool in the pull-out direction. Energy corresponding to the sum of energy used for deformation of both the energy absorbing means and the second energy absorbing means is absorbed.

  Here, as described above, in the webbing take-up device according to the present invention, regardless of the rotation speed of the spool in the pull-out direction, deformation occurs in the first energy absorbing means, and the spool rotates in the pull-out direction by a predetermined angle. Otherwise, the interference of the second locking means by the regulating means cannot be resolved. Thereby, the start of energy absorption in the 2nd energy absorption means can be delayed rather than the start of energy absorption in the 1st energy absorption means, As a result, the amount of energy absorption can be increased in steps.

  Moreover, even if the interference of the second locking means by the restricting means is eliminated, the second locking means does not operate unless the rotational speed in the pull-out direction of the spool is equal to or higher than the speed at which the second locking means is operated. There is no deformation of the second energy absorbing means. When the vehicle body suddenly decelerates, the occupant's body moves inertially toward the front of the vehicle, and the rotation speed of the spool in the pull-out direction generated when the webbing belt attached to the occupant's body is pulled by the occupant's body is The bigger the physique, the faster. Therefore, by applying the configuration according to the present invention, the second energy absorption is performed according to the occupant's physique without using a physique detection sensor (for example, a load sensor provided on the seat) for detecting the occupant's physique. It is possible to switch whether or not energy absorption is performed by means.

  A webbing retractor according to a second aspect of the present invention is the webbing take-up device according to the first aspect of the present invention, wherein the spool is not rotatable relative to the frame for directly or indirectly supporting the spool and the second energy absorbing means. Is provided on the other of the lock bases so as to be movable toward one of the lock bases connected to the second energy absorbing means, and is engaged with either one of the drawers. A lock member for restricting rotation of the lock base in the direction, and provided so as to be able to rotate following the rotation of the spool, and when the rotational acceleration of the spool in the pull-out direction exceeds a predetermined magnitude It is displaced relative to the lock base that rotates in the pull-out direction together with the spool due to inertia, and this displacement restricts the rotation following the spool. An inertia mass body that moves the lock member closer to one of the frame and the lock base when the lock base rotates in the pull-out direction in a restricted state, and constitutes the second lock means. Furthermore, the restricting means interferes with at least one of the lock member and the inertial mass body.

  According to the webbing take-up device of the present invention described in claim 2, the webbing take-up device is coupled to the second energy absorbing unit so as not to rotate relative to the frame or the second energy absorbing unit that directly or indirectly supports the spool. The lock base is provided with a lock member. When the lock member approaches and engages the frame and the lock base that are not provided with the lock member, rotation of the lock base in the pull-out direction is restricted, and consequently, rotation of the spool in the pull-out direction is restricted. The

  On the other hand, the second lock means has an inertial mass body. Basically, when the spool rotates, the inertial mass body rotates so as to follow the spool, but the rotational acceleration of the spool in the pull-out direction is a predetermined magnitude. Beyond this, the inertial mass body is displaced relative to the lock base that rotates in the pull-out direction together with the spool. When the inertial mass body is displaced as described above, the rotation of the inertial mass body following the spool is restricted, and further, when the lock base rotates in the pull-out direction in the rotation restricted state of the inertial mass body, the lock member of the frame and the lock base The lock member moves closer to the side where no is provided.

  The second locking means includes such a locking member and an inertial mass body, and the restriction means interferes with at least one of the locking member and the inertial mass body. When the interference of the restricting means with the lock member and inertial mass body is eliminated, the lock member moves toward the direction of the frame and the lock base that are not provided with the lock member, or rotates in the pull-out direction together with the spool. Of the relative displacement of the inertial mass body with respect to the lock base, the operation restricted by the interference by the restricting means becomes possible, and the second lock means becomes operable.

  Thereby, the start of energy absorption in the 2nd energy absorption means can be delayed rather than the start of energy absorption in the 1st energy absorption means, As a result, the amount of energy absorption can be increased in steps.

  Moreover, as described above, the second locking means does not operate unless the rotational acceleration of the spool in the pull-out direction exceeds a predetermined magnitude in a state where interference with the locking member and the inertial mass body by the restricting means is eliminated. . For this reason, even if it does not use the physique detection sensor (for example, load sensor provided in a seat) for detecting an occupant's physique, it is switched whether energy absorption by the 2nd energy absorption means is performed according to an occupant's physique Can be performed.

  As described above, the webbing take-up device according to the present invention can change the amount of energy absorption with a relatively simple configuration, and can change the total energy absorbed according to the physique of the occupant. it can.

<Configuration of First Embodiment>
FIG. 1 is a front sectional view showing an outline of the configuration of a webbing take-up device 10 according to a first embodiment of the present invention. As shown in this figure, the webbing retractor 10 includes a frame 12 that is fastened and fixed to a predetermined portion of the vehicle body. The frame 12 includes a pair of leg plates 14 and 16. Each of the leg plates 14 and 16 is formed in a flat plate shape, and is opposed to each other in the thickness direction thereof. A spool 18 is disposed between the leg plate 14 and the leg plate 16. The spool 18 is formed in a substantially cylindrical shape whose axial direction is along the opposing direction of the leg plate 14 and the leg plate 16, and is rotatable around its own central axis.

  A longitudinal end portion of the long belt-like webbing belt 20 is locked to the spool 18. When the spool 18 rotates in the winding direction (in the direction of arrow A in each figure), which is one side around its own central axis, the webbing belt 20 is wound in layers from the base end side in the longitudinal direction to the outer peripheral portion. When the webbing belt 20 is pulled toward the tip, the webbing belt 20 wound around the spool 18 is pulled out, and the spool 18 rotates in the pulling direction opposite to the winding direction (arrow B direction in each figure).

  A torsion shaft 22 constituting an energy absorbing means is provided inside the spool 18. The torsion shaft 22 includes a spool side connecting portion 24. The outer peripheral shape of the spool-side connecting portion 24 when viewed along the axial direction of the spool 18 is a non-circular shape such as a polygon or a star. Of the inner peripheral portion of the spool 18, at least a part of the center side along the axial direction of the spool 18 has a shape corresponding to the outer peripheral shape of the spool side connecting portion 24, and the torsion shaft 22 is disposed in the spool 18. In this state, the relative rotation of the spool side connecting portion 24 (and thus the torsion shaft 22) with respect to the spool 18 around the center axis of the spool 18 is disabled.

  From the end surface on the leg plate 14 side of the spool side connecting portion 24 along the axial direction of the spool 18, the first energy absorbing portion 26 as the first energy absorbing means constituting the energy absorbing means is connected from the spool side connecting portion 24. It is formed continuously. The first energy absorbing portion 26 has a cylindrical shape whose outer peripheral shape is sufficiently smaller than the outer peripheral shape of the spool side connecting portion 24, and is connected to the spool side connecting portion 24 at one axial end thereof. A first connecting portion 28 is formed at the other end of the first energy absorbing portion 26 (an end portion of the first energy absorbing portion 26 opposite to the spool side connecting portion 24).

  A first lock base 32 constituting a first lock mechanism 30 serving as a first lock means is fitted and inserted into the leg plate 14 side of the spool 18 corresponding to the first connecting portion 28. The first lock base 32 includes a fitting insertion portion 34. The outer peripheral shape of the insertion portion 34 is circular, and the insertion portion 34 is inserted from the end of the spool 18 on the leg plate 14 side so as to be coaxially rotatable relative to the spool 18. A hole 36 opened in the end face on the leg plate 16 side is formed in the fitting insertion part 34. The cross-sectional shape of the hole portion 36 when the fitting insertion portion 34 is cut in a direction orthogonal to the axial direction of the spool 18 is a non-circular shape such as a polygon or a star shape.

  The outer peripheral shape of the first connecting portion 28 is substantially the same shape as the inner peripheral shape of the hole portion 36 (strictly, a slightly smaller similar shape), and from the opening end of the hole portion 36 on the leg plate 16 side. The first connecting portion 28 enters the inside of the hole portion 36. As described above, the inner peripheral shape of the hole portion 36 is a non-circular shape such as a polygon or a star shape, and the outer peripheral shape of the first connecting portion 28 corresponds to the inner peripheral shape of the hole portion 36. For this reason, in a state in which the first connecting portion 28 enters the inside of the hole portion 36, relative rotation of the first lock base 32 with respect to the torsion shaft 22 around the central axis of the first connecting portion 28 is disabled.

  A first lock base main body 38 is formed continuously from the end of the fitting insertion portion 34 opposite to the leg plate 16. The first lock base main body 38 passes through the leg plate 14 and enters the housing 40 of the first lock mechanism 30 attached to the leg plate 14 on the outside of the leg plate 14 (on the side opposite to the leg plate 16 of the leg plate 14). As shown in FIG. 2, which is a view taken in the direction of arrows 2 in FIGS. 1 and 1, the first lock base main body 38 has a lock pawl housing portion 42 that is open on an end surface opposite to the leg plate 16 and a part of the outer periphery. Is formed.

  A first lock pawl 44 is disposed in the lock pawl housing portion 42. The first lock pawl 44 is guided by the lock pawl housing portion 42 and is movable in the first lock direction and the first unlocking direction opposite to the first lock direction. When the first lock pawl 44 moves in the first locking direction from the state in which the lock pawl 44 is accommodated (the state indicated by the solid line in FIG. 2), the opening of the housing 40 at the outer peripheral portion of the first lock base body 38 The first lock pawl 44 protrudes outside the first lock base body 38 and approaches the inner peripheral portion of the ratchet hole 46 of the leg plate 14 through which the first lock base body 38 passes.

  As shown in FIG. 2, ratchet teeth 48 are formed at the tip of the first lock pawl 44 protruding from the first lock base body 38, and the first lock pawl 44 is formed on the inner peripheral portion of the ratchet hole 46. When approaching, the ratchet teeth 48 mesh with ratchet teeth 50 formed on the inner periphery of the ratchet hole 46. When the ratchet teeth 48 are engaged with the ratchet teeth 50 in this manner, the rotation of the first lock pawl 44 in the pull-out direction around the central axis of the spool 18 is restricted, and thus the first lock pawl 44 is By restricting rotation in the pull-out direction, rotation of the first lock base body 38 (first lock base 32) in the pull-out direction is restricted.

  On the other hand, as shown in FIG. 1, a shaft portion 52 is formed coaxially with respect to the first energy absorbing portion 26 from the end surface of the first connecting portion 28 opposite to the first energy absorbing portion 26. Yes. The shaft portion 52 penetrates the first lock base 32 and enters the inside of the housing 40. A V gear 54 is rotatably supported on the shaft portion 52 protruding from the first lock base 32. The V gear 54 is provided with a first follower (not shown) constituted by a compression coil spring, a torsion spring or the like. When the first lock base 32 rotates, the first follower locks the V gear 54 in the first lock. The base gear 32 is biased to follow, and the V gear 54 rotates to follow the first lock base 32 by the biasing force of the first tracking means.

  As shown in FIG. 2, a long hole 58 that opens toward the first lock base 32 is formed in the V gear 54. A pin 60 that protrudes from the first lock pawl 44 enters the elongated hole 58. In a state where the first lock pawl 44 is accommodated in the lock pawl accommodating portion 42 without the ratchet teeth 48 meshing with the ratchet teeth 50, the pin 60 is located on one end side in the longitudinal direction of the long hole 58. When the V gear 54 rotates relative to the first lock base 32 in the winding direction against the biasing force of the first follower from this state (that is, for example, with respect to the first lock base 32 rotating in the pull-out direction). When the rotation delay of the V gear 54 occurs, the pin 60 is guided to the long hole 58 and moves to the other end side in the longitudinal direction of the long hole 58 with the first lock pawl 44. As a result, the first lock pawl 44 moves in the first lock direction so that the ratchet teeth 48 approach the ratchet teeth 50.

  Further, a ratchet portion 62 composed of external ratchet teeth is formed on the outer peripheral portion of the V gear 54. Further, as shown in FIG. 1, an acceleration sensor 64 is arranged on the side (downward) of the ratchet portion 62 along the rotational radius direction of the V gear 54. The acceleration sensor 64 includes a base portion 66 having a curved surface that is curved so as to open toward the outer peripheral side of the ratchet portion 62. A hard ball 68 as an inertial mass body is placed on the curved surface of the base 66.

  On the hard ball 68, the sensor claw 70 is provided so as to be swingable in a direction in which the sensor claw 70 contacts and separates from the ratchet portion 62. When the hard ball 68 is inertially moved to the front side of the vehicle in the vehicle suddenly decelerating state, the hard ball 68 rises on the curved surface of the base 66, and when the sensor claw 70 is pushed up by the hard ball 68, the sensor claw 70 is moved to the ratchet portion. Engage with ratchet teeth formed on the outer periphery of 62. Thus, in the state in which the sensor claw 70 is engaged with the ratchet teeth of the ratchet portion 62, the rotation of the V gear 54 in the pull-out direction is restricted.

  Further, as shown in FIG. 1, a first W pawl 72 is provided on the opposite side of the V gear 54 from the first lock base 32. As shown in FIG. 3, which is a view taken in the direction of the arrow 3 in FIG. 1, the first W pawl 72 is positioned at a position shifted in the rotational radius direction of the V gear 54 with respect to the penetrating portion of the shaft portion 52 in the V gear 54. A support shaft 74 protruding from 54 is supported so as to be able to swing (turn) around an axis parallel to the rotation axis direction of the spool 18. A pawl biasing spring 76 constituted by a compression coil spring is disposed at the center of the shaft portion 52 and the side of the center of the first W pawl 72.

  One end of the pawl biasing spring 76 is in pressure contact with a locking wall 78 formed on the V gear 54. In contrast, the other end of the pawl biasing spring 76 is in pressure contact with the bottom of the locking groove 80 formed in the first W pawl 72 so as to open toward the locking wall 78. As described above, the first W pawl 72 is swingably supported by the support shaft 74, but the first W pawl 72 swings in the winding direction around the support shaft 74 (the direction of arrow C in FIG. 3). To this end, the pawl biasing spring 76 must be compressed against the biasing force of the pawl biasing spring 76, and the first W pawl 72 is swung relative to the V gear 54 in the winding direction. Motion) is suppressed by the pawl biasing spring 76.

  On the other hand, an engaging claw 82 is formed on the first W pawl 72 on the opposite side of the pawl biasing spring 76 via the support shaft 74 and the shaft portion 52. Corresponding to the engaging claw 82, the first lock mechanism 30 includes a sensor holder 92. The sensor holder 92 includes a wall portion 94 facing the V gear 54 along the axial direction of the spool 18, and a ring-shaped ratchet portion 96 is formed on the surface of the wall portion 94 facing the V gear 54. Has been. The inner peripheral portion of the ratchet portion 96 faces the first W pawl 72 along the rocking radial direction of the first W pawl 72 around the support shaft 74, and the first W pawl 72 is wound in the winding direction with respect to the V gear 54. When the rocking is relatively swung, the tip of the engaging claw 82 approaches the inner peripheral portion of the ratchet portion 96 and engages with ratchet teeth formed on the inner peripheral portion of the ratchet portion 96. Thus, in a state where the tip end portion of the engaging claw 82 is engaged with the ratchet teeth of the ratchet portion 96, the swing of the first W pawl 72 in the pulling direction around the support shaft 74 is restricted, and consequently in the pulling direction. The rotation of the V gear 54 is restricted.

  That is, in the first lock mechanism 30, the first lock base 32, the lock pawl housing portion 42, the first lock pawl 44, and the ratchet portion 62 constitute a so-called “VSIR mechanism”, and the first lock base 32, the lock pawl housing The portion 42, the first lock pawl 44, the first W pawl 72, the pawl biasing spring 76, and the ratchet portion 96 (sensor holder 92) constitute a so-called “WSIR mechanism”.

  On the other hand, as shown in FIG. 1, the second energy as the second energy absorbing means constituting the energy absorbing means is formed from the end face on the leg plate 16 side of the spool side connecting portion 24 along the axial direction of the spool 18. The absorbing portion 126 is formed continuously from the spool side connecting portion 24. The second energy absorbing portion 126 has a cylindrical shape whose outer peripheral shape is sufficiently smaller than the outer peripheral shape of the spool side connecting portion 24, and is connected to the spool side connecting portion 24 at one axial end thereof.

  A second connecting portion 128 is formed at the other end of the second energy absorbing portion 126 (the end of the second energy absorbing portion 126 opposite to the spool side connecting portion 24). A second lock base 132 that constitutes a second lock mechanism 130 as a second lock means is fitted into the spool 18 on the side of the leg plate 14 corresponding to the second connecting portion 128. The second lock base 132 has basically the same configuration as the first lock base 32 described above, and is directed from the end portion of the spool 18 on the leg plate 16 side to the fitting insertion portion 34 to be fitted on the spool 18 toward the leg plate 14 side. Thus, a non-circular hole portion 36 that is opened is formed, and the second connection portion 128 whose outer peripheral shape corresponds to the inner peripheral shape of the hole portion 36 is inserted into the hole portion 36 in the same manner as the first connection portion 28. Thereby, in the state where the second connecting portion 128 has entered the inside of the hole portion 36, the relative rotation of the second lock base 132 with respect to the torsion shaft 22 around the central axis of the second connecting portion 128 is disabled.

  A second lock base main body 138 is formed continuously from the end of the insertion portion 34 opposite to the leg plate 16. The second lock base body 138 passes through the leg plate 16 and enters the housing 140 of the second lock mechanism 130 attached to the leg plate 16 on the outside of the leg plate 16 (on the side opposite to the leg plate 14 of the leg plate 16). As shown in FIG. 4, which is a view taken along line 4 in FIGS. 1 and 1, the second lock base main body 138 has a lock pawl housing portion 142 that is open on an end surface opposite to the leg plate 14 and a part of the outer periphery. Is formed. A second lock pawl 144 serving as a lock member is disposed in the lock pawl housing 142.

  The second lock pawl 144 is guided by the lock pawl housing part 142 and can move in the second lock direction and the first unlocking direction opposite to the second lock direction. When the second lock pawl 144 moves in the second locking direction from the state in which the lock pawl 144 is accommodated (the state shown by the solid line in FIG. 4), the opening of the housing 140 at the outer peripheral portion of the second lock base body 138 The second lock pawl 144 protrudes outside the second lock base body 138 and approaches the inner peripheral portion of the ratchet hole 146 of the leg plate 16 through which the second lock base body 138 passes.

  As shown in FIG. 4, ratchet teeth 148 are formed at the tip of the second lock pawl 144 protruding from the second lock base body 138, and the second lock pawl 144 is formed at the inner periphery of the ratchet hole 146. When approaching, the ratchet teeth 148 mesh with the ratchet teeth 150 formed on the inner periphery of the ratchet hole 146. When the ratchet teeth 148 are engaged with the ratchet teeth 150 in this way, the rotation of the second lock pawl 144 in the pull-out direction around the central axis of the spool 18 is restricted, and thus the second lock pawl 144 is By restricting the rotation in the pull-out direction, the rotation of the second lock base body 138 (second lock base 132) in the pull-out direction is restricted.

  On the other hand, as shown in FIG. 1, a shaft portion 152 is formed so as to protrude coaxially with respect to the second energy absorbing portion 126 from the end surface of the second connecting portion 128 opposite to the second energy absorbing portion 126. Yes. The shaft portion 152 passes through the second lock base 132 and enters the inside of the housing 140. A follower rotator 154 is rotatably supported on the shaft portion 152 protruding from the second lock base 132. The follower rotator 154 is basically a member having the same function as the V gear 54 in the first lock mechanism 30, but unlike the V gear 54, a ratchet portion 62 is formed on the outer peripheral portion of the follower rotator 154. Absent.

  Similarly to the first follower means provided in the V gear 54, the follower rotating body 154 is provided with a second follower means (not shown) constituted by a compression coil spring, a torsion spring or the like. When the second lock base 132 rotates, the second follower urges the follower rotator 154 to follow the second lock base 132, and the follower rotator 154 becomes the second by the urging force of the second follower. It rotates to follow the lock base 132. Further, as shown in FIG. 4, follow-up rotation is performed in the same manner as a long hole 58 is formed in the V gear 54 and the pin 60 protruding from the first lock pawl 44 enters the long hole 58. A long hole 158 is formed in the body 154, and a pin 160 projecting from the second lock pawl 144 enters the long hole 158.

  Similar to the functions of the long hole 58 and the pin 60, the follower rotator 154 rotates relative to the second lock base 132 in the winding direction against the urging force of the second follower, so that the pin 160 is oblong. 158 is guided to move to the other end in the longitudinal direction of the long hole 158 with the second lock pawl 144. As a result, the second lock pawl 144 moves in the second lock direction so that the ratchet teeth 148 approach the ratchet teeth 150.

  Further, as shown in FIG. 1, a second W pawl 172 as an inertial mass body is provided on the opposite side of the follower rotator 154 from the second lock base 132. As shown in FIG. 5, which is a view taken along line 5 in FIG. 1, the second W pawl 172 is shifted from the penetrating portion of the shaft portion 152 in the follower rotator 154 in the rotational radius direction of the follower rotator 154. A support shaft 174 protruding from the follower rotator 154 is supported so as to be able to swing (rotate) about an axis parallel to the rotation axis direction of the spool 18.

  A pawl biasing spring 176 formed of a compression coil spring is disposed at the center of the shaft portion 152 and the side of the center of the second W pawl 172. One end of the pawl biasing spring 176 is in pressure contact with a locking wall 178 formed on the follower rotator 154. In contrast, the other end of the pawl biasing spring 176 is in pressure contact with the bottom of the locking groove 180 formed in the second W pawl 172 so as to open toward the locking wall 178. As described above, the second W pawl 172 is swingably supported by the support shaft 174, but the second W pawl 172 swings in the winding direction around the support shaft 174 (the direction of arrow D in FIG. 5). In this case, the pawl biasing spring 176 must be compressed against the biasing force of the pawl biasing spring 176, and the second W pawl 172 is swung relative to the follower rotating body 154 in the winding direction ( Rotation) is suppressed by the pawl biasing spring 176.

  On the other hand, an engaging claw 182 is formed on the second W pawl 172 on the side opposite to the pawl biasing spring 176 via the support shaft 174 and the shaft portion 152. The second lock mechanism 130 includes a housing ratchet 192 corresponding to the engaging claw 182. The housing ratchet 192 has basically the same structure as the sensor holder 92 in the first lock mechanism 130, and includes a wall portion 194 that faces the follower rotating body 154 along the axial direction of the spool 18. A ring-shaped ratchet 196 is formed on the surface facing the rotating body 154.

  The inner peripheral portion of the ratchet portion 196 is opposed to the second W pawl 172 along the rocking radial direction of the second W pawl 172 around the support shaft 174, and the second W pawl 172 is wound around the follower rotator 154. When rocking relatively in the direction, the tip of the engaging claw 182 approaches the inner peripheral portion of the ratchet portion 196 and engages with ratchet teeth formed on the inner peripheral portion of the ratchet portion 196. In this way, in a state where the tip end portion of the engaging claw 182 is engaged with the ratchet teeth of the ratchet portion 196, the swing of the second W pawl 172 in the pulling direction around the support shaft 174 is restricted, and consequently in the pulling direction. The rotation of the follower rotator 154 is restricted.

  That is, the first lock mechanism 30 has a configuration including a “VSIR mechanism” and a “WSIR mechanism”, whereas the second lock mechanism 130 does not include a “VSIR mechanism” but a “WSIR mechanism”. It consists only of.

  On the other hand, as shown in FIG. 6, which is a view taken along line 6 in FIG. 1, a guide groove 212 is formed at the end of the spool 18 on the leg plate 14 side. The guide groove 212 is formed in an annular shape that is substantially coaxial with the center axis of the spool 18, and opens at the end of the spool 18 on the leg plate 14 side. Further, as shown in FIGS. 1 and 6, a through hole 214 is formed in the spool 18. The through hole 214 is formed parallel to the center axis of the spool 18 at a position displaced in the rotational radial direction of the spool 18 with respect to the through hole of the spool 18 through which the torsion shaft 22 passes. As shown in FIG. 1, the end of the through hole 214 on the leg plate 16 side is open at the end of the spool 18 on the leg plate 16 side. On the other hand, as shown in FIGS. 1 and 6, the end of the through hole 214 on the side of the leg plate 14 opens at the bottom of the guide groove 212.

  Further, as shown in FIG. 1, the webbing retractor 10 includes a delay wire 222 that constitutes a restricting means as an activation delay means. As shown in FIGS. 1 and 8A, the delay wire 222 includes a wire body 224. The wire body 224 is formed in a rod shape whose outer peripheral shape is substantially equal to the inner peripheral shape of the through hole 214 or smaller than the inner peripheral shape of the through hole 214, and is accommodated inside the through hole 214. As shown in FIGS. 8A and 8B, a curved portion 226 is formed continuously from the end of the wire body 224 on the leg plate 14 side.

  The curved portion 226 is curved so as to follow the guide groove 212, and is accommodated in the guide groove 212 along the guide groove 212 from the opening end of the through hole 214 at the bottom of the guide groove 212. An engaging portion 228 is formed continuously from the end of the bending portion 226 opposite to the wire body 224. The engaging portion 228 extends from the bending portion 226 in the direction opposite to the extending direction of the wire body 224 from the bending portion 226.

  As shown in FIG. 7, which is a view taken along line 7 in FIG. 1, a retaining hole 230 is formed in the fitting insertion portion 34 of the first lock base 32 so as to correspond to the engaging portion 228. The distal end side of the portion 228 (the side opposite to the curved portion 226 of the engaging portion 228) enters the retaining hole 230. A flange-shaped head portion 232 is formed at the tip of the engaging portion 228. When the engaging portion 228 is accommodated in the retaining hole 230, the retaining portion 228 comes out from the retaining hole 230 toward the leg plate 16. When the engagement portion 228 is about to move, the inner wall of the retaining hole 230 interferes with the head portion 232 and restricts the movement of the engagement portion 228.

  As described above, the side of the delay wire 222 housed in the through hole 214 opposite to the curved portion 226 of the wire body 224 protrudes from the opening end of the through hole 214 on the leg plate 16 side. A through hole 242 is formed in the second lock base body 138 of the second lock base 132 corresponding to the through hole 214 protruding from the opening end of the through hole 214 on the leg plate 16 side. One end of the through hole 242 opens at the end surface of the second lock base body 138 on the leg plate 14 side, and the other end opens at the bottom of the lock pawl housing 142.

  The delay wire 222 protruding from the opening end of the through hole 214 on the leg plate 16 side passes through the through hole 242 and enters the lock pawl housing part 142. A notch 244 is formed in the second lock pawl 144 corresponding to the wire main body 224 (delay wire 222) that has entered the lock pawl housing 142, and the wire main body 224 that has entered the lock pawl housing 142 has a second shape. The lock pawl 144 enters the inside of the notch 244. When the second lock pawl 144 attempts to move in the second locking direction (that is, the direction in which the ratchet teeth 148 mesh with the ratchet teeth 150 of the ratchet hole 146) with the wire main body 224 entering the inside of the notch 244, the wire The main body 224 interferes with the inner wall (that is, the second lock pawl 144) of the notch 244, and restricts the movement of the second lock pawl 144 in the second lock direction.

<Operation and Effect of First Embodiment>
Next, the operation and effect of the present embodiment will be described through the operation of the webbing take-up device 10.

(Operation of the VSIR mechanism of the first lock mechanism 30)
In the webbing take-up device 10, when a vehicle occupant wears the webbing belt 20 pulled out from the spool 18 and the vehicle suddenly decelerates, the hard ball 68 of the acceleration sensor 64 rolls by inertia and the base 66. The curved surface rises and the hard ball 68 pushes up the sensor claw 70. The sensor claw 70 pushed up by the hard ball 68 engages with the ratchet teeth of the ratchet portion 62 formed on the V gear 54, thereby restricting the rotation of the V gear 54 in the drawing direction. When the vehicle body suddenly decelerates and the occupant's body moves inertially toward the front side of the vehicle, the webbing belt 20 attached to the occupant's body is pulled, thereby rotating the spool 18 in the pull-out direction. Since the spool 18 is connected to the first lock base 32 so as not to rotate relative to the first lock base 32 by the torsion shaft 22, the first lock base 32 rotates in the pull-out direction when the spool 18 rotates in the pull-out direction.

  As described above, when the rotation of the V gear 54 in the pull-out direction is restricted by the sensor claw 70 and the first lock base 32 rotates in the pull-out direction together with the spool 18, the first lock base 32 and the V gear 54 Relative rotation occurs between them. When the first lock base 32 rotates relative to the V gear 54 in the pull-out direction, the elongated hole 58 moves in the first lock direction with the first lock pawl 44 while being guided by the pin 60. Accordingly, the ratchet teeth 48 of the first lock pawl 44 mesh with the ratchet teeth 50 of the ratchet hole 46 formed in the leg plate 14. As described above, the ratchet teeth 48 of the first lock pawl 44 mesh with the ratchet teeth 50 of the leg plate 14, thereby restricting the rotation of the first lock base 32 in the pull-out direction.

(Operation of WSIR mechanism of first lock mechanism 30)
On the other hand, when the body of an occupant who intends to move inertially toward the front side of the vehicle suddenly pulls the webbing belt 20 when the vehicle suddenly decelerates, the spool 18 is suddenly rotated in the pull-out direction. When the spool 18 is suddenly rotated in the pulling direction, the first lock base 32 is suddenly rotated in the pulling direction, and the urging force of the first follower means causes the V gear 54 to be suddenly rotated in the pulling direction. . When the V gear 54 suddenly rotates in the pull-out direction in this way, a rotation delay of the first W pawl 72 with respect to the V gear 54 occurs against the biasing force of the pawl biasing spring 76, thereby causing the first W pawl 72 to move to the V gear 54. It swings relative to the gear 54 in the winding direction.

  By the relative swinging of the first W pawl 72, the engaging claw 82 formed on the first W pawl 72 is engaged with the ratchet portion 96 of the sensor holder 92. Thus, the engagement claw 82 is engaged with the ratchet portion 96, so that the rotation of the V gear 54 in the pull-out direction is restricted. As described above, in this state, the occupant's body is pulling the webbing belt 20, and therefore, the rotation of the V gear 54 in the pull-out direction is restricted, so that the first lock base 32 and the V gear 54 are interposed. Relative rotation occurs. As a result, as described above, the ratchet teeth 48 of the first lock pawl 44 mesh with the ratchet teeth 50 of the ratchet holes 46 formed in the leg plate 14, and the rotation of the first lock base 32 in the pull-out direction is restricted.

(Behavior of the torsion shaft 22 when the first lock mechanism 30 is operating)
As described above, when at least one of the VSIR mechanism and the WSIR mechanism of the first lock mechanism 30 operates, the rotation of the first lock base 32 in the pull-out direction, and consequently the rotation of the spool 18 in the pull-out direction. As a result, the pull-out of the webbing belt 20 from the spool 18 is restricted, so that the occupant's body is strongly restrained by the worn webbing belt 20, and the occupant's front side due to the sudden deceleration of the vehicle Inertial movement of the body is prevented or effectively suppressed.

  On the other hand, when the rotational force of the spool 18 in the pull-out direction generated by the occupant's body pulling the webbing belt 20 exceeds the mechanical strength of the first energy absorbing portion 26 of the torsion shaft 22, the first lock base 32 is used. Thus, the spool-side connecting portion 24, which is a connecting portion with the spool 18, rotates in the drawing direction with respect to the first connecting portion 28 of the torsion shaft 22 whose rotation in the pulling-out direction is restricted. The first energy absorber 26 is deformed so that the absorber 26 is twisted.

  Although the first lock base 32 is restricted from rotating in the pull-out direction, the spool 18 can rotate in the pull-out direction by the amount of twisting of the first energy absorbing portion 26, and as a result, the webbing belt 20 can be pulled out from the spool 18. it can. In addition, at least a part of the energy that the occupant's body pulls the webbing belt 20 is consumed as the energy that is used for the deformation of the first energy absorbing portion 26, whereby at least one of the energy that the occupant's body pulls the webbing belt 20 is consumed. Part is absorbed.

(Operation of delay wire 222)
Further, as described above, when the spool 18 rotates in the pull-out direction with respect to the first lock base 32 whose rotation is restricted, the retaining hole 230 formed in the first lock base main body 38 (first lock base 32). However, it rotates around the central axis of the spool 18 with respect to the through hole 214 formed in the spool 18, whereby the retaining hole 230 is separated from the through hole 214 in the winding direction. Thus, when the retaining hole 230 is displaced relative to the through hole 214 in the winding direction, the engaging portion 228 of the delay wire 222 held by the first lock base 32 by the retaining hole 230 is the first. It rotates (displaces) together with the lock base 32. The wire main body 224 is pulled out from the opening end of the through hole 214 on the leg plate 14 side by the amount of the displacement of the engaging portion 228, and the drawn out wire main body 224 is curved following the guide groove 212.

  Thus, when the wire main body 224 is pulled out from the opening end of the through hole 214 on the leg plate 14 side, the vicinity of the end of the wire main body 224 opposite to the curved portion 226 comes out of the lock pawl housing portion 142, and further , Through the through hole 242 and drawn into the through hole 214. As a result, the interference of the second lock pawl 144 by the wire body 224 is released, and the relative rotation of the second lock base 132 with respect to the spool 18 by the wire body 224 is canceled by the wire body 224 coming out of the through hole 242 as well. Is done.

(Operation of the second lock mechanism 130)
As described above, when the spool 18 is suddenly rotated in the pull-out direction while the interference of the second lock pawl 144 by the wire body 224 is released, the second lock base 132 is rapidly rotated in the pull-out direction. Furthermore, the urging force of the second follow-up means makes the follow-up rotating body 154 suddenly rotate in the pull-out direction. When the follower rotator 154 suddenly rotates in the pull-out direction in this manner, a rotation delay of the second W pawl 172 with respect to the follower rotator 154 occurs against the urging force of the pawl urging spring 176, thereby causing the second W pawl 172. Swings relative to the follower rotator 154 in the winding direction.

  By the relative swinging of the second W pawl 172, the engaging claw 182 formed on the second W pawl 172 is engaged with the ratchet portion 196 of the housing ratchet 192. Thus, the engagement claw 182 is engaged with the ratchet portion 196, so that the rotation of the follow-up rotating body 154 in the pull-out direction is restricted. As described above, in this state, since the occupant's body is pulling the webbing belt 20, the rotation of the follower rotator 154 in the pull-out direction is restricted, so that the second lock base 132 and the follower rotator 154 Relative rotation occurs between them. Thereby, as described above, the ratchet teeth 148 of the second lock pawl 144 mesh with the ratchet teeth 150 of the ratchet hole 146 formed in the leg plate 16, and the rotation of the second lock base 132 in the pull-out direction is restricted.

(Behavior of torsion shaft 22 when second lock mechanism 130 is in operation)
As described above, the operation of the WSIR mechanism of the second lock mechanism 130 restricts the rotation of the second lock base 132 in the pull-out direction, and consequently the rotation of the spool 18 in the pull-out direction. In this state, if the rotational force of the spool 18 in the pull-out direction generated by the occupant's body pulling the webbing belt 20 exceeds the mechanical strength of the second energy absorbing portion 126 of the torsion shaft 22, the second lock With respect to the second connecting portion 128 of the torsion shaft 22 that is restricted from rotating in the pull-out direction via the base 132, the spool-side connecting portion 24, which is a connecting portion with the spool 18, rotates in the pull-out direction. The second energy absorber 126 is deformed so that the second energy absorber 126 is twisted.

  Although the second lock base 132 is restricted from rotating in the pull-out direction, the spool 18 can rotate in the pull-out direction by the amount of twist of the second energy absorbing portion 126, and as a result, the webbing belt 20 can be pulled out from the spool 18. it can. In addition, at least a part of the energy that the occupant's body pulls the webbing belt 20 is consumed as energy that is used for the deformation of the second energy absorbing portion 126, and thus, the occupant's body pulls at least one of the energy that pulls the webbing belt 20. Part is absorbed.

(Characteristic action and effect of the webbing take-up device 10)
Here, in the state where the deformation of the second energy absorption unit 126 is started as described above, the deformation of the first energy absorption unit 26 has already been started, and thus the state where the second energy absorption unit 126 is deformed. Then, the energy corresponding to the sum of the energy used for the deformation of the second energy absorbing unit 126 and the energy used for the deformation of the first energy absorbing unit 126 out of the energy of the occupant's body pulling the webbing belt 20. Absorbed.

  By the way, as described above, the second lock pawl 144 cannot move in the second lock direction until the interference of the wire main body 224 (delay wire 222) is released. The other end of the second lock pawl 144 is interfered by the wire body 224 (delay wire 222) unless the opposite end comes out of the lock pawl accommodating portion 142 and passes through the through hole 242 and enters the through hole 214. Is not released. Thus, in order for the end of the wire main body 224 opposite to the curved portion 226 to come out of the lock pawl accommodating portion 142 and enter the through hole 214, the end of the wire main body 224 opposite to the curved portion 226 The wire body 224 has to be pulled out from the end of the through hole 214 on the leg plate 14 side by a length corresponding to the amount of movement of the end of the through hole 214, and the spool 18 has the first lock base at an angle corresponding to that length. It must rotate in the pull-out direction with respect to 32.

  That is, in the webbing take-up device 10, there is a time delay from the start of torsional deformation of the first energy absorption unit 26 to the start of torsional deformation of the second energy absorption unit 126. Arise. For this reason, until the torsional deformation of the second energy absorption unit 126 is started, the energy corresponding to the deformation of the first energy absorption unit 26 out of the energy with which the body of the occupant pulls the webbing belt 20 is equivalent. When the energy is absorbed and then the second energy absorption unit 126 is deformed, the energy used for the deformation of the second energy absorption unit 126 is superimposed on the energy absorption amount thus far. Thereby, in this webbing retractor 10, the amount of energy absorbed by the occupant's body pulling the webbing belt 20 can be increased stepwise.

  In addition, as described above, even if the end of the wire main body 224 opposite to the curved portion 226 comes out of the lock pawl housing portion 142, the second W pawl 172 is not delayed in rotation with respect to the follower rotating body 154. The second lock base 132 is not restricted in rotation. That is, for example, when the occupant wearing the webbing belt 20 is relatively small, the second energy pawl 172 with respect to the follower rotator 154 is generated in this state although torsional deformation occurs in the first energy absorber 26. In the case where the rotational speed of the spool 18 in the pull-out direction is increased only to such an extent as not to cause the rotational delay, the second energy absorbing portion 126 is not twisted. For this reason, energy absorption according to a crew member's physique and the deceleration state of vehicles is attained.

  Furthermore, in the webbing take-up device 10, as described above, the end of the wire body 224 opposite to the curved portion 226 comes out of the lock pawl housing portion 142 and the second lock mechanism 130 can be operated. When the second lock mechanism 130 is operated, the second connecting portion 128 is held, and the second energy absorbing portion 126 can be deformed. For this reason, since expensive trigger means such as a gas generator is not required for holding the second connecting portion 128 and starting the operation of the second lock mechanism 130, the cost can be reduced.

<Configuration of Second Embodiment>
Next, a second embodiment of the present invention will be described. In the description of the present embodiment, the same reference numerals are given to the same parts as those in the first embodiment, and the detailed description thereof is omitted.

  FIG. 9 is a front sectional view showing an outline of the configuration of the webbing take-up device 300 according to the present embodiment. As shown in this figure, the webbing retractor 300 does not include the torsion shaft 22, but instead includes a torsion shaft 302 that constitutes an energy absorbing means. The torsion shaft 302 is the same as the torsion shaft 22 in the first embodiment in that the spool-side connecting portion 24 and the first connecting portion 28 are provided, but the leg plate 16 of the spool-side connecting portion 24 of the torsion shaft 302 is the same. The second energy absorbing portion 126 and the second connecting portion 128 are not provided at the end portion on the side.

  In the first embodiment, the spool-side connecting portion 24 of the torsion shaft 22 is generally located in the vicinity of the central portion in the axial direction of the spool 18. (In the present embodiment, the spool-side connecting portion 24 of the torsion shaft 302 is located near the opening end of the spool 18 on the leg plate 16 side). .

  Moreover, a shaft portion 152 is formed coaxially with respect to the first energy absorbing portion 26 from the end portion on the leg plate 16 side of the spool side connecting portion 24 of the torsion shaft 302. Further, in the torsion shaft 22 in the first embodiment, the spool-side connecting portion 24 is connected to the spool 18 in a state in which the spool-side connecting portion 24 cannot rotate relative to the spool 18, but in this embodiment as well, the spool of the torsion shaft 302 is connected. The side connecting portion 24 is connected to the spool 18 in a state in which it cannot rotate relative to the spool 18.

  The second locking mechanism 130 as the second locking means of the webbing take-up device 300 does not include the second lock base 132 but includes the second lock base 312 instead. The second lock base 312 is fitted so as to be coaxially rotatable relative to the spool 18 from the opening end of the spool 18 on the leg plate 16 side. However, as described above, in the present embodiment, since the second connection portion 128 is not formed on the torsion shaft 302, the second lock base 312 is formed with the hole portion 36 into which the second connection portion 128 is inserted. However, the shaft portion 152 penetrates through the second lock base 312, so that the second lock base 312 is rotatably supported by the shaft portion 152.

  On the other hand, as shown in FIG. 10, which is a view taken along line 10 in FIG. 9, in the webbing retractor 300, a guide groove 318 is formed at the end of the spool 18 on the leg plate 16 side. Similar to the guide groove 212 formed at the end of the spool 18 on the leg plate 14 side, the guide groove 318 is formed in an annular shape that is substantially coaxial with the central axis of the spool 18, and the end of the spool 18 on the leg plate 16 side. Open at the part.

  In the webbing take-up device 300, a through hole 322 is formed in the spool 18 separately from the through hole 214. Similar to the through hole 214, the through hole 322 is formed parallel to the center axis of the spool 18 at a position displaced in the rotational radius direction of the spool 18 with respect to the through hole of the spool 18 through which the torsion shaft 22 passes. . As shown in FIG. 9, the end of the through hole 322 on the leg plate 16 side is open at the end of the spool 18 on the leg plate 16 side.

  Further, as shown in FIG. 9, the webbing retractor 300 includes an energy absorbing wire 332 10 as the second energy absorbing unit constituting the energy absorbing unit. As shown in FIGS. 9 and 12, the energy absorbing wire 332 includes a wire body 334. The wire body 334 is formed in a rod shape whose outer peripheral shape is substantially equal to the inner peripheral shape of the through hole 322 or smaller than the inner peripheral shape of the through hole 322, and is accommodated inside the through hole 322. As shown in FIGS. 12A and 12B, a curved portion 336 is formed continuously from the end of the wire body 334 on the leg plate 14 side.

  The curved portion 336 is curved so as to follow the guide groove 318, and is accommodated in the guide groove 318 along the guide groove 318 from the opening end of the through hole 322 at the bottom of the guide groove 318. An engaging portion 338 is formed continuously from the end of the bending portion 336 opposite to the wire body 334. The engaging portion 338 extends from the bending portion 336 in the direction opposite to the extending direction of the wire body 334 from the bending portion 336.

  As shown in FIG. 11, which is a view taken in the direction of arrow 11 in FIG. 9, a retaining hole 340 is formed in the fitting insertion portion 34 of the second lock base 312 corresponding to the engaging portion 338, and The distal end side of the portion 338 (the side opposite to the bending portion 336 of the engaging portion 338) enters the retaining hole 340. A flange-shaped head portion 342 is formed at the tip of the engaging portion 338, and when the engaging portion 338 is accommodated in the retaining hole 340, the retaining portion 338 comes out of the retaining hole 340 toward the leg plate 16. When the engaging portion 338 is about to move, the inner wall of the retaining hole 340 interferes with the head portion 342 and restricts the movement of the engaging portion 338.

<Operation and Effect of Second Embodiment>
Next, the operation and effect of the present embodiment will be described through the operation of the webbing take-up device 300.

  In the webbing take-up device 300, after the first lock mechanism 30 starts to operate, the second lock mechanism 130 operates to rotate the second lock base 132 in the pull-out direction, and in turn to pull the spool 18 in the pull-out direction. Until the rotation is restricted, the webbing take-up device 300 basically performs the same operation as that of the webbing take-up device 10 according to the first embodiment. For this reason, in this respect, the same effect as in the first embodiment can be obtained, and the same effect as in the first embodiment can be obtained.

(Behavior of energy absorbing wire 332)
In the webbing take-up device 300, the second lock base 312 of the second lock mechanism 130 is fitted and inserted from the end of the spool 18 on the leg plate 16 side so as to be rotatable relative to the spool 18 coaxially. The lock base 312 is supported on the shaft portion 152 of the torsion shaft 302 so as to be relatively rotatable coaxially with the torsion shaft 302.

  However, in the state where the end of the wire body 224 (delay wire 222) near the end opposite to the curved portion 226 passes through the through hole 242 and enters the lock pawl housing 142, the wire body 224 (delay wire) 222), the relative rotation of the second lock base 312 with respect to the spool 18 is restricted. Since the torsion shaft 302 is connected to the spool 18 at the spool side connecting portion 24 so as not to rotate relative to the spool 18, the relative rotation of the second lock base 312 with respect to the spool 18 is restricted by the wire body 224 (delay wire 222). In the state, the relative rotation of the second lock base 312 with respect to the torsion shaft 302 is also indirectly restricted.

  As described in the first embodiment, the vicinity of the end of the wire main body 224 (delay wire 222) opposite to the curved portion 226 is drawn into the through hole 214, so that the lock pawl housing portion 142 and the through hole are provided. When the wire main body 224 comes out of 242, the relative rotation restriction of the second lock base 312 with respect to the spool 18 by the wire main body 224 (delay wire 222) is released. In this state, when the spool 18 is suddenly rotated in the pull-out direction, the WSIR mechanism of the second lock mechanism 130 is operated, and the ratchet hole 148 formed in the leg plate 16 has the ratchet teeth 148 of the second lock pawl 144. 146 meshes with the ratchet teeth 150, and the rotation of the second lock base 132 in the pull-out direction is restricted.

  As described above, in this state, the relative rotation restriction of the second lock base 312 with respect to the spool 18 by the wire body 224 (delay wire 222) is released, but the wire body 334 is inserted into the through hole 322 of the spool 18. Since the head 342 of the energy absorbing wire 332 enters the retaining hole 340 formed in the second lock base 312, the relative rotation restriction of the second lock base 312 with respect to the spool 18 is restricted by the energy absorbing wire 332. Is done. In this state, if the rotational force of the spool 18 in the pull-out direction generated by the occupant's body pulling the webbing belt 20 exceeds the mechanical strength of the energy absorbing wire 332, the second lock base that is restricted in rotation. The spool 18 rotates in the pull-out direction with respect to 312.

  Due to the rotation of the spool 18 in the pull-out direction, the retaining hole 340 formed in the second lock base body 138 (second lock base 312) becomes the center of the spool 18 with respect to the through hole 322 formed in the spool 18. By rotating around the axis, the retaining hole 340 is separated from the through hole 322 in the winding direction. When the retaining hole 340 is displaced in the winding direction relative to the through-hole 322 in this way, the engaging portion 338 of the energy absorbing wire 332 held by the second lock base 312 through the retaining hole 340 becomes the first. 2 Turns (displaces) together with the lock base 312.

  The wire main body 334 is pulled out from the opening end of the through hole 322 on the leg plate 16 side by the displacement of the engaging portion 338, and the pulled out wire main body 334 enters the guide groove 336 and bends along the guide groove 336. When the wire main body 334 pulled out from the opening end of the through hole 322 on the leg plate 16 side enters the guide groove 336, the wire main body 334 has a longitudinal direction along the circumferential direction of the spool 18, It deforms by squeezing at the opening edge.

  Thus, the spool 18 can rotate in the pull-out direction by the length of the wire main body 334 (energy absorbing wire 332) pulled out from the through-hole 322 and into the guide groove 336. As a result, the webbing belt 20 is pulled out from the spool 18. be able to. In addition, at least a part of the energy that the occupant's body pulls the webbing belt 20 is consumed as energy when the wire body 334 is squeezed and deformed at the opening edge of the through-hole 322, whereby the occupant's body is At least a portion of the energy pulling is absorbed.

(Characteristic operations and effects of the webbing retractor 300)
Here, as described above, in the state where the drawing of the wire main body 334 (energy absorption wire 332) from the through hole 322 is started, the deformation of the first energy absorption portion 26 of the torsion shaft 302 has already started. In the state where the wire body 334 (energy absorbing wire 332) is pulled out from the through-hole 322 and squeezed, the body of the occupant is subjected to squeezing deformation of the energy absorbing wire 332 out of the energy that pulls the webbing belt 20. The energy corresponding to the sum of the energy and the energy provided for the deformation of the first energy absorbing portion 126 of the torsion shaft 302 is absorbed.

  By the way, as described above, the second lock pawl 144 cannot move in the second lock direction until the interference of the wire main body 334 (energy absorbing wire 332) is released, and the curved portion 226 of the wire main body 224 is not allowed. The end of the second lock pawl 144 by the wire main body 224 (delay wire 222) must come out of the end of the lock pawl accommodating portion 142, and pass through the through hole 242 and not enter the through hole 214. Interference is not released. Thus, in order for the end of the wire main body 224 opposite to the curved portion 226 to come out of the lock pawl accommodating portion 142 and enter the through hole 214, the end of the wire main body 224 opposite to the curved portion 226 The wire body 224 must be pulled out from the end of the through hole 214 on the leg plate 14 side by a length corresponding to the amount of movement of the end of the through hole 214, and the spool 18 is moved to the second lock base by an angle corresponding to that length. It must rotate in the pull-out direction with respect to 312.

  That is, in the webbing take-up device 300, after the torsional deformation of the first energy absorbing portion 26 of the torsion shaft 302 is started, the wire body 334 (energy absorbing wire 332) is pulled out from the through hole 322 and the iron deformation is deformed. There will be a time delay before starting. For this reason, until the squeezing deformation of the energy absorbing wire 332 is started, it corresponds to the energy used for the deformation of the first energy absorbing portion 26 of the torsion shaft 302 among the energy of the occupant's body pulling the webbing belt 20. When energy is absorbed and then the energy absorbing wire 332 is ironed and deformed, the energy used for the iron absorbing deformation of the energy absorbing wire 332 is superimposed on the energy absorption amount thus far. Thereby, in this webbing retractor 300, the amount of energy absorbed by the occupant's body pulling the webbing belt 20 can be increased stepwise.

  As described above, in the present webbing take-up device 300, although the configuration of the second energy absorbing unit is different from that of the first embodiment, the start of the deformation of the second energy absorbing unit is started. Therefore, the webbing take-up device 300 according to the present embodiment can achieve the same effects as those of the webbing take-up device 10 according to the first embodiment.

(Supplementary information)
In each of the above embodiments, the second lock pawl 144 moves in the second lock direction when the wire main body 224 of the delay wire 222 interferes with the second lock pawl 144, that is, the second lock mechanism 130. However, the restricting means only needs to be able to restrict the operation of the second lock means (the second lock mechanism 130 in the above embodiments). Therefore, the delay wire 222 only needs to be able to restrict the operation of the second lock mechanism 130 as a result. For example, the wire main body 224 may be configured to restrict the swing of the second W pawl 172 until it is pulled into the through hole 214. The wire body 224 may be configured to restrict the relative rotation of the second W pawl 172 with respect to the second lock base 132 until the wire body 224 is pulled into the through hole 214. Furthermore, the wire main body 224 may be configured to interfere with both the second lock pawl 144 and the second W pawl 172.

  Further, in each of the above embodiments, the ratchet teeth 48 of the first lock pawl 44 provided on the first lock base 32 mesh with the ratchet teeth 50 of the ratchet hole 46 formed in the leg plate 14 of the frame 12. It was the structure which controls the rotation to the drawing-out direction of the 1st connection part 28 of the torsion shaft 22. However, the configuration of the first locking means is not limited to such a configuration.

  For example, ratchet teeth are formed on the outer peripheral portion of the first lock base main body 38 (first lock base 32), and a lock pawl is provided so as to be movable toward and away from the outer peripheral portion of the first lock base main body 38. The first locking means is operated in the deceleration state and the spool 18 is suddenly rotated in the pulling direction so that the lock pawl is engaged with the ratchet teeth of the first lock base main body 38, and the first lock base 32, and thus the torsion shaft. It is good also as a structure which controls the rotation to the drawing-out direction of the 22nd 1st connection part 28. FIG.

  Further, in each of the above-described embodiments, the ratchet teeth 148 of the second lock pawl 144 provided on the second lock bases 132 and 312 mesh with the ratchet teeth 150 of the ratchet hole 146 formed in the leg plate 16 of the frame 12. Thus, the rotation of the second connecting portion 128 of the torsion shaft 22 in the pull-out direction is restricted. However, the configuration of the second locking means is not limited to such a configuration.

  For example, the ratchet teeth are formed on the outer peripheral portion of the second lock base main body 138 (second lock base 132, 312), and the lock as a lock member is movable toward and away from the outer peripheral portion of the second lock base main body 138. When the spool 18 is suddenly rotated in the pull-out direction with the pawl provided and the restriction of the movement of the lock pawl by the delay wire 222 is eliminated, the second locking means is activated and the lock pawl is ratchet on the second lock base body 138. It is good also as a structure which mesh | engages with a tooth | gear and controls the rotation to the drawing-out direction of the 2nd lock base 132,312.

  In the second embodiment, the torsion shaft 302 is the first energy absorbing means, and the energy absorbing wire 332 is the second energy absorbing means. However, the first energy absorbing unit and the second energy absorbing unit are not limited to the modes described in the above embodiments. For example, a retaining hole 340 that accommodates the engaging portion 338 of the energy absorbing wire 332 and interferes with the head portion 342 is formed in the fitting insertion portion 34 of the first lock base 32, and the energy absorbing wire is formed in the first lock base 32. 332 is engaged with the torsion shaft 302 on the leg plate 14 side so as not to rotate relative to the spool 18, and on the leg plate 16 side with respect to the second lock base body 138 of the second lock base 312. It is also possible to adopt a configuration in which the relative rotation is impossible. In such a configuration, the torsion shaft 302 becomes the second energy absorbing means, and the energy absorbing wire 332 becomes the first energy absorbing means.

  Further, the two energy absorbing wires 332 are provided without providing the torsion shafts 22 and 302, the engaging portion 338 of one energy absorbing wire 332 is engaged with the first lock base 32, and the other energy absorbing wire 332 is provided. The engaging portion 338 may be engaged with the second lock base 312. In such a configuration, one energy absorption wire 332 engaged with the first lock base 32 serves as the first energy absorption means, and the other energy absorption wire 332 engaged with the second lock base 312 serves as the second energy. Absorbing means.

It is front sectional drawing which shows the outline of a structure of the webbing winding apparatus which concerns on the 1st Embodiment of this invention. FIG. 2 is a view taken in the direction of the arrow 2 in FIG. 1 showing the configuration of the main part of the first locking means. FIG. 3 is a view taken in the direction of arrows 3 in FIG. 1 showing the configuration of the main part of the first locking means. FIG. 4 is a view taken in the direction of arrow 4 in FIG. 1 showing the configuration of the main part of the second locking means. FIG. 5 is a view taken in the direction of arrow 5 in FIG. 1 showing the configuration of the main part of the second locking means. FIG. 6 is a view taken along line 6 of FIG. 1 showing an end portion of the spool on the first locking means side. FIG. 7 is a view taken in the direction of the arrow 7 in FIG. 1 showing the spool-side end of the first lock base. (A) is a front view which shows the structure of a control means, (B) is a side view which shows the structure of a control means. It is front sectional drawing which shows the outline of a structure of the webbing winding apparatus which concerns on the 2nd Embodiment of this invention. FIG. 10 is a view taken from the direction of the arrow 10 in FIG. 9, showing the end of the spool on the second locking means side. FIG. 10 is a view on the spool side of the second lock base, taken along line 11 in FIG. 9. (A) is a front view which shows the structure of a 2nd energy absorption means, (B) is a side view which shows the structure of a 2nd energy absorption means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Webbing winding device 12 Frame 18 Spool 20 Webbing belt 26 1st energy absorption part (1st energy absorption means)
30 First lock mechanism (first lock means)
32 1st lock base 126 2nd energy absorption part (2nd energy absorption means)
130 Second locking mechanism (second locking means)
132 Second lock base 144 Lock pawl (lock member)
172 2nd W Paul (Inertial Mass)
222 Delay wire (regulation means)
300 Webbing Winder 312 Second Lock Base 322 Energy Absorbing Wire (Second Energy Absorbing Means)

Claims (2)

The longitudinal base end side of the long belt-like webbing belt is locked, and the webbing belt is wound and stored from the longitudinal base end side by rotating in one winding direction around the axis. A spool to which a rotational force in a pulling direction opposite to the winding direction is applied when pulled to the tip side;
First energy absorption that is provided on the spool so as to be rotatable together with the spool and is deformed by applying a rotational force exceeding its own mechanical strength to the spool in a state in which the rotation in the pull-out direction is restricted. Means,
First lock means for restricting rotation of the first energy absorbing means in the pull-out direction in at least one of a state of sudden deceleration of the vehicle and a state in which the spool is rotated at a predetermined speed or more in the pull-out direction; ,
Second energy absorption that is provided in the spool so as to be rotatable together with the spool and is deformed by applying a rotational force exceeding its own mechanical strength to the spool in a state in which the rotation in the pull-out direction is restricted. Means,
When the spool is rotated in the pull-out direction at the same speed as the predetermined speed at which the first lock means is operated or the speed different from the predetermined speed in a state where the operation restriction is eliminated , Second locking means for restricting rotation of the second energy absorbing means;
The second locking unit interferes with the second locking unit to restrict the operation of the second locking unit, and the first energy absorbing unit rotates in the pulling-out direction of the first energy absorbing unit in the pulling-out direction. Restricting means that operates in conjunction with rotation of the spool, and cancels interference with the second locking means by rotating the spool by a predetermined angle in the pull-out direction;
A webbing take-up device comprising: Moves in a direction approaching either one of the frame supporting the spool directly or indirectly and the lock base connected to the second energy absorbing means so as not to rotate relative to the second energy absorbing means. A locking member that is provided on any other of the above, and that engages with one of the above to restrict the rotation of the lock base in the pull-out direction;
The lock base is provided so as to be able to rotate following the rotation of the spool, and when the rotational acceleration of the spool in the pull-out direction exceeds a predetermined magnitude, the lock base rotates in the pull-out direction together with the spool due to inertia. And the rotation following the spool is restricted by this displacement, and the lock base is rotated in the pull-out direction in this rotation restricted state, so that the lock member is either the frame or the lock base. An inertial mass that moves closer to one of the
2. The webbing retractor according to claim 1, wherein the second locking unit is configured to further include at least one of the locking member and the inertia mass body.

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