JP7135726B2 - Webbing take-up device - Google Patents

Description

The present invention relates to a webbing take-up device.

Patent Document 1 below discloses a webbing take-up device that includes a spool on which a webbing (belt) is wound, a gear member that rotates integrally with the spool, and a locking pawl that is provided to engage with the gear member. is disclosed. When the energization to the solenoid is cut off, the locking claw is displaced, and the locking claw engages with the gear member, thereby rotating the spool (rotation in the direction in which the webbing is pulled out from the spool). is locked.

In addition, Patent Document 2 below discloses a webbing winding provided with a first locking means and a second locking means for locking the rotation of the spool (rotation in the direction in which the webbing is pulled out from the spool) when necessary in case of vehicle emergency or the like. A picking device is disclosed. In the webbing take-up device described in this document, the second locking means is activated when the first locking means is not activated due to failures such as poor connection of terminals or breakage of circuit portions. This makes it possible to lock the rotation of the spool even when the first locking means is not actuated.

Japanese Unexamined Patent Application Publication No. 2002-2447 Japanese Patent Application Laid-Open No. 2002-220028

By the way, in the configuration described in Patent Document 1, when the solenoid is not energized due to a malfunction of the electrical system, the rotation of the spool is locked, and it is conceivable that reattachment of the belt is prevented.

Further, in the configuration described in Patent Document 2, even when the first locking means is not operated, the rotation of the spool can be locked by the second locking means. It is necessary to provide both means, and there is room for improvement in terms of reducing the size of the webbing take-up device and reducing the number of components.

Furthermore, it is assumed that the mechanism for locking the rotation of the spool described in Patent Document 1 and Patent Document 2 is repeatedly operated due to continued use of the vehicle. Therefore, it is important to improve the durability of the mechanism for locking the rotation of the spool.

In consideration of the above facts, the issues of suppressing unnecessary locking of the rotation of the spool, the issue of reducing the size of the physique, the issue of reducing the number of component parts, and the durability of the mechanism for locking the rotation of the spool An object of the present invention is to solve at least the problem of suppressing unnecessary locking of the rotation of the spool among the problems of improving the performance.

A webbing take-up device according to claim 1 includes a spool that winds a webbing worn by an occupant and that is pulled out to rotate in a pull-out direction, and a spool that rotates integrally with the spool. A rotation lock portion provided to be displaceable in the rotation radial direction of the spool, and a rotation lock portion provided outside the rotation lock portion in the rotation radial direction of the spool with respect to the rotation lock portion. A fixed lock portion that locks the rotation of the spool in the pull-out direction; a displacement portion that displaces the rotation lock portion toward the fixed lock portion against the limitation of the displacement of the rotation lock portion, wherein the spool is pulled out at a predetermined angular acceleration when the displacement portion is not operated and the spool is pulled out. The rotation by the limiter such that the rotation lock is displaced toward the fixed lock by the inertial force that causes the rotation lock to rotate about its own rotation center when rotated at an angular acceleration exceeding In the webbing take-up device in which the restricting force of the locking portion is adjusted, the restricting force is adjusted so that unnecessary engagement of the rotation lock portion with the fixed lock portion is suppressed in normal times other than in an emergency of the vehicle. By restricting the displacement of the rotation lock portion to the fixed lock portion side, unnecessary locking of the rotation of the spool is suppressed .

According to the webbing take-up device of claim 1, the webbing is attached to the occupant by pulling out the webbing from the spool. Further, when the displacement portion is actuated in an emergency of the vehicle, the rotation lock portion is displaced toward the fixed lock portion against the limitation of displacement by the limit portion and engages with the fixed lock portion. As a result, the rotation of the spool in the pull-out direction is locked, and the pull-out of the webbing from the spool is restricted.
Here, when the displacement portion is not operated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion rotates about its own rotation center due to inertial force. is displaced toward the fixed lock portion. That is, the rotation lock portion is displaced toward the fixed lock portion against the restriction of displacement by the limit portion and engages with the fixed lock portion. As a result, the rotation of the spool in the pull-out direction is locked, and the pull-out of the webbing from the spool is restricted. Thus, when the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, that is, when the webbing is suddenly pulled out from the spool in the event of a vehicle emergency, the displacement portion is actuated. If not, rotation of the spool in the withdrawal direction can be locked to limit withdrawal of the webbing from the spool.
Here, the restricting portion restricts the displacement of the rotation lock portion toward the fixed lock portion during normal operation of the vehicle except in an emergency. As a result, unnecessary engagement of the rotation lock portion with the fixed lock portion is suppressed, and unnecessary locking of the rotation of the spool can be suppressed.

A webbing take-up device according to claim 2 is the webbing take-up device according to claim 1, which is formed using a permanent magnet fixed to the rotation lock portion and a magnetic material, and a magnetic material is used to face the permanent magnet. and an electromagnet having a core disposed and a coil disposed around the core , wherein the restricting portion is composed of the permanent magnet and the core, and the displacement portion includes: The magnetic force of the permanent magnet and the electromagnet attracting the core portion restricts the displacement of the rotation lock portion toward the fixed lock portion, thereby energizing the coil portion in one direction. As a result, a magnetic force that repels the permanent magnet is generated in the core portion, thereby displacing the rotation lock portion toward the fixed lock portion.

According to the webbing take-up device of claim 2, when the coil is energized in one direction in case of vehicle emergency, a magnetic force repulsive to the permanent magnet is generated in the core. As a result, the rotation lock portion to which the permanent magnet is fixed is displaced toward the fixed lock portion and engaged with the fixed lock portion. As a result, the rotation of the spool in the pull-out direction is locked, and the pull-out of the webbing from the spool is restricted.
In addition, when the electromagnet is not activated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion is fixed by the inertia force that causes the rotation lock portion to rotate about its own rotation center. It is displaced to the locking part side. That is, the rotation lock portion is displaced toward the fixed lock portion against the magnetic force of the permanent magnet that attracts the core portion, and engages with the fixed lock portion. As a result, the rotation of the spool in the pull-out direction is locked, and the pull-out of the webbing from the spool is restricted. Here, in normal times other than in an emergency of the vehicle, the displacement of the rotation lock portion toward the fixed lock portion is restricted by the magnetic force of the permanent magnet that attracts the core portion. As a result, unnecessary engagement of the rotation lock portion with the fixed lock portion is suppressed, and unnecessary locking of the rotation of the spool can be suppressed.

The webbing take-up device according to claim 3 is the webbing take-up device according to claim 2, in which a magnetic force that attracts the permanent magnet is generated in the core portion by energizing the coil portion in the other direction. , the displacement of the rotation lock portion toward the fixed lock portion is restricted.

According to the webbing take-up device of claim 3, when the coil portion is energized in the other direction, a magnetic force that attracts the permanent magnet is generated in the core portion. As a result, compared with the case where the coil is not energized in the other direction, it is possible to more firmly restrict the displacement of the rotation lock portion toward the fixed lock portion.

The webbing take-up device according to claim 4 is the webbing take-up device according to claim 3, wherein when the occupant pulls out the webbing from the spool to wear the webbing, the coil portion is not energized in the other direction. When the webbing is attached to the occupant, the energization of the coil portion is stopped.

According to the webbing take-up device of claim 4, when the occupant pulls out the webbing from the spool, the coil portion is energized in the other direction. As a result, the displacement of the rotation lock portion toward the fixed lock portion can be more strongly restricted. As a result, the occupant can quickly pull out the webbing from the spool and quickly wear the webbing.
Further, when the webbing is attached to the passenger, the energization of the coil portion is stopped. As a result, it is possible to suppress consumption of electric power associated with energization of the coil portion.

The webbing take-up device according to claim 5 is the webbing take-up device according to any one of claims 2 to 4, wherein the core portion is arranged on the rotation shaft of the spool. The coil portion is arranged around the upper portion of the shaft.

According to the webbing take-up device of claim 5, the upper shaft portion of the core portion that rotates integrally with the spool is arranged on the rotation shaft of the spool, and the coil portion is arranged around the upper shaft portion of the core portion. ing. As a result, it is possible to suppress the complication of the wiring route to the coil section. As a result, complication of the configuration of the webbing take-up device can be suppressed. Further, by adopting a configuration in which the coil portion does not rotate together with the spool, it is possible to reduce the number of component parts of the webbing take-up device.

The webbing take-up device according to claim 6 is the webbing take-up device according to any one of claims 2 to 5, wherein when the coil portion is energized in one direction, the rotation lock portion is displaced to a position where it can abut against the fixed lock portion, and in a state in which the rotation lock portion and the fixed lock portion are in contact with each other, the spool is rotated in the pull-out direction, whereby the rotation lock portion and the Engagement with the fixed lock is completed.

According to the webbing take-up device of the sixth aspect, when the coil portion of the electromagnet is energized in one direction, the rotation lock portion is displaced to a position where it can contact the fixed lock portion. Then, the engagement between the rotation lock portion and the fixed lock portion is completed by rotating the spool in the pull-out direction while the rotation lock portion and the fixed lock portion are in contact with each other. In this way, by adopting a configuration in which the rotation lock portion is not displaced by the electromagnet until the engagement between the rotation lock portion and the fixed lock portion is completed, an increase in size of the electromagnet (an increase in the output of the electromagnet) is suppressed. be able to. As a result, the size of the webbing take-up device can be reduced.

The webbing take-up device according to claim 7 is the webbing take-up device according to any one of claims 1 to 6, wherein the fixed lock portion is arranged at the inside portion of the spool in the rotation radial direction. and a terminal portion contacting the rotation lock portion at a portion on the outer side of the spool in the rotation radial direction, wherein the hardness of the tip portion is lower than the hardness of the terminal portion. is set.

According to the webbing take-up device of claim 7, when the displacement portion is operated and the rotation lock portion is displaced toward the fixed lock portion, the rotation lock portion comes into contact with the distal end portion of the fixed lock portion and then reaches the terminal end portion. abut. Here, the hardness of the tip portion of the rotation lock portion is set lower than the hardness of the terminal portion. As a result, the initial impact when the rotation lock portion is engaged with the fixed lock portion can be mitigated. As a result, the rotation lock portion and the fixed lock portion are prevented from being damaged, and the durability of the mechanism for locking the rotation of the spool can be improved.

The webbing take-up device according to claim 8 is the webbing take-up device according to claim 7, wherein the fixed lock portion includes a first fixed lock portion and a second fixed lock portion which are arranged adjacent to each other in the rotation axis direction of the spool. It is configured including a lock portion, wherein the terminal portion is provided on the first fixed lock portion, and the tip portion is provided on the second fixed lock portion.

According to the webbing take-up device of the eighth aspect, the fixed lock portion has hardness of the tip portion and the hardness of the end portion of the rotation lock portion by selecting the materials of the first fixed lock portion and the second fixed lock portion. and can be easily adjusted.

The webbing take-up device according to claim 9 is the webbing take-up device according to claim 1, wherein the restricting portion includes a biasing member that biases the rotation lock portion in a direction opposite to the fixed lock portion. The displacement portion includes an electromagnet having a coil portion and a moving member that moves when the coil portion is energized, and when the coil portion is energized in one direction, the When the moving member moves, the rotation locking portion is directly or indirectly pressed by the moving member, and the rotation locking portion is displaced toward the fixed locking portion.

According to the webbing take-up device of the ninth aspect, when the coil portion is energized in one direction in an emergency of the vehicle, the moving member moves. When the moving member moves, the moving member directly or indirectly presses the rotation lock. As a result, the rotation lock portion is displaced toward the fixed lock portion and engaged with the fixed lock portion. As a result, the rotation of the spool in the pull-out direction is locked, and the pull-out of the webbing from the spool is restricted.
In addition, when the electromagnet is not activated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion is fixed by the inertia force that causes the rotation lock portion to rotate about its own rotation center. It is displaced to the locking part side. That is, the rotation lock portion is displaced toward the fixed lock portion against the biasing force of the biasing member and engages with the fixed lock portion. As a result, the rotation of the spool in the pull-out direction is locked, and the pull-out of the webbing from the spool is restricted.
Here, the displacement of the rotation lock portion toward the fixed lock portion side is restricted by the biasing force of the biasing member during normal times except for emergency situations of the vehicle. As a result, unnecessary engagement of the rotation lock portion with the fixed lock portion is suppressed, and unnecessary locking of the rotation of the spool can be suppressed.

The webbing take-up device according to claim 10 is the webbing take-up device according to any one of claims 1 to 9, wherein the rotation lock portion includes a first rotation lock portion and the first rotation lock portion. and a second rotation lock portion arranged adjacent to each other along the rotation axis direction of the spool, wherein the second rotation lock portion locks the spool with respect to the first rotation lock portion. The second rotation lock portion is displaced radially outwardly of the spool with respect to the first rotation lock portion, and the second rotation lock portion displaces the first rotation lock portion. engages the fixed lock portion before the portion.

According to the webbing take-up device of claim 10, the second rotation lock portion is displaced radially outward of the spool relative to the first rotation lock portion, and the second rotation lock portion is displaced from the first rotation lock portion. is also engaged with the fixed lock portion first. Thereby, the impact when the rotation lock portions (the first rotation lock portion and the second rotation lock portion) are engaged with the fixed lock portion can be distributed to the first rotation lock portion and the second rotation lock portion.

The webbing take-up device according to the present invention has an excellent effect of suppressing unnecessary locking of the rotation of the spool.

1 is a perspective view showing a main part of a webbing take-up device of this embodiment; FIG. FIG. 3 is an enlarged perspective view showing an enlarged lock mechanism of the webbing take-up device of the present embodiment; FIG. 11 is a side view showing a state in which the rotation lock portion tilted by the operation of the electromagnet is in contact with the fixed lock portion; FIG. 4 is a side view corresponding to FIG. 3, showing a state in which the spool is rotated 8 degrees in the pull-out direction from the state shown in FIG. 3; FIG. 4 is a side view corresponding to FIG. 3, showing a state in which the spool is rotated 10° in the pull-out direction from the state shown in FIG. 4; FIG. 4 is a side view corresponding to FIG. 3 , showing a state in which the spool is rotated 15° in the pull-out direction from the state shown in FIG. 5 and the rotation of the spool is locked; FIG. 3 is an enlarged perspective view corresponding to FIG. 2 showing an enlarged lock mechanism in a state where rotation of the spool is locked; FIG. 7 is a side view showing a state in which the rotation lock portion has been completely engaged with the fixed lock portion, and is a side view seen from the side opposite to the side shown in FIG. 6 ; (A) is a side view showing another lock mechanism before the electromagnet is actuated, and (B) is a plan view showing the relationship between the electromagnet and the load transmission section. (A) is a side view showing another lock mechanism in a state where the electromagnet is actuated, and (B) is a plan view showing the relationship between the electromagnet and the load transmission section. (A) is a side view showing another lock mechanism in a state where the engagement of the rotation lock portion with the fixed lock portion is completed, and (B) is a plan view showing the relationship between the electromagnet and the load transmission portion. . FIG. 11 is a perspective view showing another form of lock mechanism; FIG. 13 is a perspective view of another form of the lock mechanism as seen from the opposite side to FIG. 12; FIG. 4 is a side view showing the first rotation lock portion, the second rotation lock portion, etc. in a state in which the electromagnet is actuated; FIG. 15 is a side view corresponding to FIG. 14, showing a state in which the spool has rotated in the pull-out direction from the state shown in FIG. 14; FIG. 15 is a side view corresponding to FIG. 14, showing a state in which the spool is rotated in the pull-out direction from the state shown in FIG. 15; FIG. 17 is a side view corresponding to FIG. 14, showing a state in which the spool has rotated in the pull-out direction from the state shown in FIG. 16; FIG. 18 is a side view corresponding to FIG. 14, showing a state in which the spool has rotated in the pull-out direction from the state shown in FIG. 17; FIG. 19 is a side view corresponding to FIG. 14, showing a state in which the spool rotates in the pull-out direction from the state shown in FIG. 18 and rotation of the spool is locked;

A webbing take-up device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8. FIG. The direction of arrow Z, the direction of arrow R, and the direction of arrow C, which are appropriately shown in the drawings, indicate the rotation axis direction, the rotation radial direction, and the rotation circumferential direction of the spool, respectively. Further, hereinafter, when simply indicating the axial direction, the radial direction, and the circumferential direction, it indicates the axial direction of the spool, the radial direction of rotation, and the circumferential direction of rotation, unless otherwise specified.

As shown in FIG. 1, a webbing take-up device 10 of the present embodiment includes a spool 14 on which a webbing 12 worn by an occupant is taken up, a frame 16 fixed to a vehicle body or a vehicle seat, and an emergency device of the vehicle. and a lock mechanism 18 that locks the rotation of the spool 14 in the pull-out direction (arrow C direction).

The spool 14 has a winding portion 14A around which the webbing is wound. The webbing 12 is wound on the winding portion 14A of the spool 14 by rotating the spool 14 in the winding direction (opposite direction to arrow C) by the biasing force of a spring (not shown). Further, the webbing 12 is pulled out from the spool 14 so that the spool 14 is rotated in the pull-out direction.

The frame 16 includes a pair of side walls 16A spaced apart from each other in the axial direction, and a base wall 16B connecting ends on one side of the pair of side walls 16A. A spool 14 is arranged between the pair of side walls 16A. Further, by fixing the base wall 16B to the vehicle body or the vehicle seat, the webbing take-up device 10 is fixed to the vehicle body or the vehicle seat.

The lock mechanism 18 is provided so as to be integrally rotatable with the spool 14 and is provided so as to be tiltable (displaceable) in the rotational radial direction of the spool 14. The rotation lock portion 20 is engaged with the rotation lock portion 20. and a fixed lock portion 22 that locks the rotation of the spool 14 in the pull-out direction. The lock mechanism 18 includes a permanent magnet 24 as a restriction portion and a displacement portion fixed to the rotation lock portion 20, and a restriction portion that tilts the rotation lock portion 20 or restricts tilting of the rotation lock portion 20 by being actuated. and an electromagnet 26 as a portion and a displacement portion.

As shown in FIG. 2, the rotation lock portion 20 is formed using a metal material. The rotation lock portion 20 is formed in a substantially half-moon shape when viewed from the axial direction. A circular support hole 20</b>A is formed through the center portion of the rotation lock portion 20 in the axial direction. Through a support pin 28 inserted into the support hole 20A, the rotation lock portion 20 is fixed to a portion radially outside of the rotation axis (rotation center) of the spool 14 at one axial end of the spool 14. It is Two main engagement teeth 20B that engage with a fixed lock portion 22, which will be described later, are formed on the outer peripheral portion of the end portion of the rotation lock portion 20 on one side in the circumferential direction (pull-out direction side). A sub-engaging tooth 20C is formed on the other side in the axial direction (the side opposite to the arrow Z) of the main engaging tooth 20B on the side closer to the support pin 28 . A portion of the sub-engaging tooth 20</b>C on one side in the circumferential direction protrudes toward one side in the circumferential direction with respect to the main engaging tooth 20</b>B on the side closer to the support pin 28 . In this embodiment, the thickness (dimension in the axial direction) of the main engaging tooth 20B is set to be thicker than the thickness (dimension in the axial direction) of the sub-engaging tooth 20C. A rectangular parallelepiped permanent magnet 24 is fixed to the inner peripheral portion of the end portion of the rotation lock portion 20 on one side in the circumferential direction (the pull-out direction side).

The fixed lock portion 22 includes a first fixed lock portion 30 and a second fixed lock portion 32 that are arranged adjacent to each other in the rotation axis direction of the spool 14 . The first fixed lock portion 30 and the second fixed lock portion 32 are fixed to the side wall 16A and the like (see FIG. 1) of the frame while being arranged radially outwardly of the rotation lock portion 20. As shown in FIG.

The first fixed lock portion 30 is formed using a metal material like the rotation lock portion 20 and is formed in an annular shape coaxial with the rotation axis of the spool 14 . A plurality of main engaged teeth 30</b>A with which the main engaging teeth 20</b>B of the rotation locking portion 20 engage are formed on the inner peripheral portion of the first fixed locking portion 30 . The plurality of main engaged teeth 30A are arranged at regular intervals in the circumferential direction.

The second fixed lock portion 32 is arranged on the other side in the axial direction with respect to the first fixed lock portion 30 . The second fixed lock portion 32 is formed using a resin material having a lower hardness than the metal material forming the first fixed lock portion 30 and the rotation lock portion 20, and is arranged coaxially with the rotation axis of the spool 14. It is formed in an annular shape. A plurality of sub-engaged teeth 32A with which the sub-engagement teeth 20C of the rotation lock portion 20 are engaged are formed on the inner peripheral portion of the second fixed lock portion 32 . The plurality of sub-engaged teeth 32A are arranged at regular intervals in the circumferential direction. In this embodiment, the thickness (dimension in the axial direction) of the main engaged tooth 30A is set thicker than the thickness (dimension in the axial direction) of the sub-engaged tooth 32A.

As shown in FIG. 3, when viewed from the axial direction, the tip portion 32B of the sub engaged tooth 32A of the second fixed lock portion 32 is the tip portion 30B of the main engaged tooth 30A of the first fixed lock portion 30. protrudes radially inward. In addition, a surface 32D on the other side in the circumferential direction of the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 is the other circumferential surface of the tip portion 30B of the main engaged tooth 30A of the first fixed lock portion 30. It is positioned on the other side in the circumferential direction of the side surface 30D. In addition, the end portions 32C of the sub-engaged teeth 32A of the second fixed lock portion 32 (between the sub-engaged teeth 32A adjacent in the circumferential direction) are the main engaged teeth 30A of the first fixed lock portion 30 It is recessed radially outward from the terminal end portion 30C (between the circumferentially adjacent main engaged teeth 30A).

As shown in FIG. 1, the electromagnet 26 includes a core portion 34 made of a magnetic material and a coil portion 36 arranged around the core portion 34 .

The core portion 34 is formed by bending a rod-shaped member having a round cross section into an L shape, and is attached to the spool 14 via a support member (not shown) so as to be integrally rotatable. The core portion 34 includes a shaft upper portion 34A arranged on the rotation shaft of the spool 14, and a facing portion 34B bent and extending radially outward from the end portion of the shaft upper portion 34A on the spool 14 side. there is The radially outer surface of the facing portion 34B faces the permanent magnet 24 fixed to the rotation lock portion 20 in the radial direction.

The coil portion 36 is formed in a cylindrical shape by winding a conductive wire in a predetermined shape. A shaft upper portion 34A of the core portion 34 is inserted into the shaft core portion of the coil portion 36 . Also, the coil portion 36 is supported by the frame 16 or the like via a support member (not shown). In addition, the coil portion 36 is energized through wiring (not shown).

As shown in FIGS. 1 and 2, when the coil portion 36 is not energized, the permanent magnet 24 contacts the opposing portion 34B of the core portion 34 due to the magnetic force that attracts the core portion 34. ing. As a result, tilting of the rotation lock portion 20 to which the permanent magnet 24 is fixed toward the fixed lock portion 22 is restricted. Here, when the webbing 12 is abruptly pulled out from the spool 14, the spool 14 abruptly rotates in the pull-out direction. Then, the rotation lock portion 20 tends to tilt toward the fixed lock portion 22 due to the inertial force of the rotation lock portion 20 rotating about its own rotation center. When this inertial force exceeds the magnetic force of the permanent magnet 24 that attracts the core 34, the rotation lock portion 20 tilts toward the fixed lock portion 22, causing the rotation lock portion 20 (main engagement tooth 20B and sub-engagement tooth 20C) to tilt. engages with the fixed lock portion 22 (the main engaged tooth 30A of the first fixed lock portion 30 and the sub-engaged tooth 32A of the second fixed lock portion 32). In this embodiment, while the coil portion 36 is not energized, the webbing 12 is pulled out from the spool 14 at a speed at which a vehicle collision or sudden deceleration is assumed, and the spool 14 is pulled out at a predetermined angle in the pull-out direction. The magnetic force of the permanent magnet 24 and the like are set so that the rotation lock portion 20 tilts toward the fixed lock portion 22 when rotated at an angular acceleration exceeding the acceleration.

Further, when the coil portion 36 is energized in one direction and a magnetic force repulsive to the permanent magnet 24 is generated in the core portion 34, the rotation lock portion 20 is moved to the fixed lock portion as indicated by the two-dot chain line in FIG. 22 is tilted. Here, in this embodiment, when the coil portion 36 is energized in one direction, the distal end portions of the sub-engaging tooth 20C of the rotation lock portion 20 and the sub-engaged tooth 32A of the second fixed lock portion 32 32B in the circumferential direction. That is, the rotation lock portion 20 is not displaced by the electromagnet 26 until the engagement between the rotation lock portion 20 and the fixed lock portion 22 is completed.

Further, when the coil portion 36 is energized in the other direction and a magnetic force that attracts the permanent magnet 24 is generated in the core portion 34, the permanent magnet 24 is stronger than when the coil portion 36 is not energized. It contacts the facing portion 34B of the portion 34 (the permanent magnet 24 and the core portion 34 attract each other). As a result, tilting of the rotation lock portion 20 to which the permanent magnet 24 is fixed toward the fixed lock portion 22 is more strongly restricted.

(Action and effect of the present embodiment)
Next, the operation and effects of this embodiment will be described.

As shown in FIGS. 1 and 2 , according to the webbing take-up device 10 of the present embodiment, the webbing 12 is pulled out from the spool 14 so that the webbing 12 is attached to the passenger. Here, in the present embodiment, when the ignition of the vehicle is ON and the occupant is not wearing the webbing 12, the coil portion 36 is energized in the other direction. As a result, a magnetic force that attracts the permanent magnet 24 is generated in the core portion 34, and the permanent magnet 24 contacts the opposing portion 34B of the core portion 34 more firmly than when the coil portion 36 is not energized. As a result, even if the webbing 12 is quickly pulled out from the spool 14 , the rotation lock portion 20 does not tilt toward the fixed lock portion 22 , so the occupant can quickly put on the webbing 12 . Then, when it is detected by a buckle switch or the like that the webbing 12 is attached to the occupant, the energization of the coil portion 36 is stopped.

Further, when it is detected by a buckle switch or the like that the occupant has removed the webbing 12, the coil portion 36 is energized in the other direction. As a result, a magnetic force that attracts the permanent magnet 24 is generated in the core portion 34, and the permanent magnet 24 contacts the opposing portion 34B of the core portion 34 more firmly than when the coil portion 36 is not energized. Accordingly, even if the webbing 12 is wound onto the spool 14 and the rotation of the spool 14 is suddenly stopped, the rotation lock portion 20 is less likely to tilt toward the fixed lock portion 22 side. As a result, unnecessary engagement of the rotation lock portion 20 with the fixed lock portion 22 is suppressed, and unnecessary locking of the rotation of the spool 14 can be suppressed.

When the webbing 12 is attached to the passenger and the vehicle is operating normally (when the vehicle is not in an emergency), the coil portion 36 is not energized. As a result, power consumption during normal operation of the vehicle is suppressed.

Further, in case of emergency of the vehicle, the coil portion 36 is energized in one direction. As a result, a magnetic force that repels the permanent magnet 24 is generated in the core portion 34 , and the rotation lock portion 20 to which the permanent magnet 24 is fixed tilts toward the fixed lock portion 22 . Here, the term "vehicle emergency" refers to a case where it is judged necessary to restrain the occupant in the vehicle seat, such as when the vehicle collides, overturns, falls, or when a collision is expected. That is. The judgment criteria for the emergency of the vehicle may be appropriately set in consideration of the criteria for the injury value of the occupant. For example, the vehicle may be judged to be in an emergency when acceleration in the longitudinal direction and the lateral direction of the vehicle acts on the vehicle at a predetermined value or more. Further, the case where the direction of the resultant force of gravity and inertial force acting on the vehicle deviates by a predetermined angle or more from the reference axis of the vehicle may be used as a judgment criterion for emergency of the vehicle. In this embodiment, the unidirectional energization of the coil portion 36 is continued from when it is determined that the vehicle is in an emergency state until it is determined that it is in a normal state of the vehicle. When it is determined that the vehicle is in a normal state after it is determined that the vehicle is in an emergency state, the coil portion 36 is energized in the other direction. As a result, the magnetic force between the permanent magnet 24 and the core portion 34 causes the rotation lock portion 20 to quickly return (tilt) to a position where it does not engage with the fixed lock portion 22 .

When the rotation lock portion 20 is tilted toward the fixed lock portion 22 by energizing the coil portion 36 in one direction, the sub-engagement tooth 20C of the rotation lock portion 20 and the sub engaged tooth 20C of the second fixed lock portion 32 are engaged. The tip portion 32B of the coupling tooth 32A overlaps in the circumferential direction. In this state, when the occupant wearing the webbing 12 moves forward with respect to the vehicle seat and the webbing 12 is pulled out from the spool 14, the spool 14 is rotated in the pull-out direction. Then, as indicated by a two-dot chain line in FIG. 3, the sub-engaging tooth 20C of the rotation lock portion 20 and the distal end portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 come into contact with each other in the circumferential direction.

When the webbing 12 is further pulled out from the spool 14 after the sub-engaging tooth 20C of the rotation lock portion 20 and the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 come into contact with each other in the circumferential direction, the spool 14 is further rotated in the pull-out direction. Then, as shown in FIGS. 4 and 5, the sub-engaging tooth 20C of the rotation locking portion 20 moves along the sub-engaged tooth 32A of the second fixed locking portion 32. As shown in FIGS. As a result, the rotation lock portion 20 is further tilted toward the fixed lock portion 22 side, and the main engaging tooth 20B of the rotation lock portion 20 moves toward the end portion 30C of the main engaged tooth 30A of the first fixed lock portion 30. Moving. Further, when the webbing 12 is further pulled out from the spool 14, the spool 14 is further rotated in the pulling direction, and as shown in FIGS. The terminal portion 30C of the main engaged tooth 30A of the portion 30 is contacted. In this state, rotation of the spool 14 in the pull-out direction is locked, and pull-out of the webbing 12 from the spool 14 is restricted. As a result, the body of the occupant is restrained by the webbing 12 .

Here, when the webbing 12 is suddenly pulled out from the spool 14 in the case where a failure occurs such that the coil portion 36 cannot be energized or the ignition is turned off (when the coil portion 36 is not energized), the rotation lock portion The rotation lock portion 20 is displaced toward the fixed lock portion 22 due to the inertial force caused by the rotation of the rotation lock portion 20 about its own rotation center. Then, as the webbing 12 is further pulled out from the spool 14, the rotation lock portion 20 (the main engaging tooth 20B and the sub-engaging tooth 20C) is moved to the fixed lock portion 22 (the main engaged tooth of the first fixed lock portion 30). 30A and the sub-engaged teeth 32A) of the second fixed lock portion 32). As a result, the rotation of the spool 14 in the pull-out direction is locked, and the pull-out of the webbing 12 from the spool 14 is restricted. As a result, the occupant's body is restrained by the webbing 12 . As described above, in the present embodiment, the webbing 12 is abruptly pulled out from the spool 14 in the event of an emergency of the vehicle when a failure occurs such that the coil portion 36 cannot be energized or when the ignition is turned off. The body of the occupant can be restrained by the webbing 12 even when the vehicle occupies the seat. If the webbing 12 becomes slack after the occupant's body is restrained by the webbing 12 , the magnetic force of the permanent magnet 24 attracting the core 34 causes the rotation lock portion 20 to return to a position where it does not engage with the fixed lock portion 22 . (Tilt).

In addition, in the present embodiment, the tilting of the rotation lock portion 20 toward the fixed lock portion 22 is restricted by the magnetic force of the permanent magnet 24 that draws the core portion 34 in normal times except in an emergency of the vehicle. As a result, unnecessary engagement of the rotation lock portion 20 with the fixed lock portion 22 is suppressed, and unnecessary locking of the rotation of the spool 14 can be suppressed.

Furthermore, in this embodiment, the upper shaft portion 34A of the core portion 34 that rotates integrally with the spool 14 is arranged on the rotation shaft of the spool 14, and the coil portion 36 is arranged around the upper shaft portion 34A of the core portion 34. It is Accordingly, it is possible to prevent the wiring route to the coil portion 36 from becoming complicated. As a result, complication of the configuration of the webbing take-up device 10 can be suppressed. In addition, since the coil portion 36 does not rotate together with the spool 14, the number of component parts of the webbing take-up device 10 can be reduced.

Further, in this embodiment, the rotation lock portion 20 is not displaced by the electromagnet 26 until the engagement between the rotation lock portion 20 and the fixed lock portion 22 is completed. As a result, it is possible to suppress an increase in the size of the electromagnet 26 (an increase in the output of the electromagnet). As a result, the size of the webbing take-up device 10 can be reduced.

Furthermore, as shown in FIG. 3, in this embodiment, when the rotation lock portion 20 is engaged with the fixed lock portion 22, first, the sub-engagement tooth 20C of the rotation lock portion 20 and the second fixed lock portion 32 are engaged. contact with the tip portion 32B of the sub-engaged tooth 32A. In this manner, the sub-engaging tooth 20C of the metal rotation lock portion 20 and the distal end portion 32B of the sub-engaged tooth 32A of the resin-made second fixed lock portion 32 first come into contact with each other. The initial impact when the rotation lock portion 20 engages with the fixed lock portion 22 can be mitigated. As a result, damage to the rotation lock portion 20 and the fixed lock portion 22 is suppressed, and the durability of the lock mechanism 18 for locking the rotation of the spool 14 can be improved.

Further, in this embodiment, the fixed lock portion 22 has a divided structure of the first fixed lock portion 30 and the second fixed lock portion 32 . Accordingly, by selecting materials for the first fixed lock portion 30 and the second fixed lock portion 32, the hardness and strength of each can be easily adjusted.

(Other forms of locking mechanism)
Next, another form of the lock mechanism 38 will be described with reference to FIGS. 9 and 10. FIG. In the lock mechanism 38 of another embodiment, the members and portions corresponding to the lock mechanism 18 described above are denoted by the same reference numerals as the members and portions corresponding to the lock mechanism 18 described above, and the description thereof can be omitted. be.

As shown in FIGS. 9A and 9B, the lock mechanism 38 locks the rotation of the spool 14 in the pull-out direction by engaging the rotation lock portion 20 with the rotation lock portion 20 . and a fixed lock portion 22 to be fixed. The lock mechanism 38 also includes a return spring 40 as a restricting portion and a biasing member that biases the rotation lock portion 20 to the side opposite to the fixed lock portion 22 . Further, the lock mechanism 38 includes an electromagnet 26 having a coil portion 36, a moving member 42 that moves in one axial direction when the coil portion 36 is energized, and a return member that biases the moving member 42 in the other axial direction. and an actuator 46 having a spring 44 .

A support hole 20A is formed at the end of the rotation lock portion 20 on the other side in the circumferential direction. Through a support pin 28 inserted into the support hole 20A, the rotation lock portion 20 is fixed to a portion radially outside of the rotation axis (rotation center) of the spool 14 at one axial end of the spool 14. It is A load transmission portion 48 formed in a substantially U shape when viewed from the axial direction is fixed to the inner peripheral portion of the end portion of the rotation lock portion 20 on one side in the circumferential direction (the pull-out direction side). Furthermore, one end of the return spring 40 is locked to the intermediate portion of the rotation lock portion 20 in the circumferential direction. The other end of the return spring 40 is engaged with the one axial end of the spool 14 .

A moving member 42 that constitutes a part of the actuator 46 is formed in a rod shape that is arranged coaxially with the rotating shaft of the spool 14 . A portion of the moving member 42 is formed with an engaging groove 42A recessed toward the axial center of the moving member 42 along the entire circumference.

When the load transmission portion 48 fixed to the rotation lock portion 20 is arranged in the engagement groove 42A of the moving member 42, the rotation lock portion 20 (main engagement teeth 20B and sub-engaging teeth 20C) are located at positions where they do not engage with the fixed lock portion 22 (the main engaged teeth 30A of the first fixed lock portion 30 and the sub-engaged teeth 32A of the second fixed lock portion 32). .

As shown in FIGS. 10A and 10B, when the coil portion 36 is energized and the moving member 42 moves to one side in the axial direction, the load transmitting portion 48 engages the engagement groove 42A of the moving member 42. As shown in FIGS. get out of As a result, the rotation lock portion 20 is pressed via the load transmission portion 48 and moves radially outward. As a result, the rotation lock portion 20 is extended to the position where the sub-engaging tooth 20C of the rotation lock portion 20 and the distal end portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 overlap in the circumferential direction. tilted to the side.

(Operation and effects of the lock mechanism 38 of the present embodiment)
Next, the operation and effects of the lock mechanism 38 of this embodiment will be described.

In the webbing take-up device provided with the lock mechanism 38 of the present embodiment, the coil portion 36 is energized in one direction in an emergency of the vehicle. 10A and 10B, the moving member 42 moves to one side in the axial direction, and the load transmitting portion 48 is pulled out of the engaging groove 42A of the moving member 42. As shown in FIGS. As a result, the rotation lock portion 20 is pressed via the load transmission portion 48 and moves radially outward. As a result, the rotation lock portion 20 is rotated to the position where the sub-engaging tooth 20C of the rotation lock portion 20 and the distal end portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 overlap in the circumferential direction. tilted to the side. If it is determined that the webbing 12 is not pulled out from the spool 14 after it is determined that the vehicle is in an emergency state, and it is determined that the vehicle is in a normal state, the power supply to the coil portion 36 is cut off. As a result, the moving member 42 is returned to the other side in the axial direction by the biasing force of the return spring 44, and the rotation lock portion 20 is returned to the position where it does not engage with the fixed lock portion 22 by the biasing force of the return spring 40 (load transmission portion 48 returns to a position where it engages with the engaging groove 42A of the moving member 42).

An occupant wearing the webbing 12 sits on the vehicle seat while the sub-engaging tooth 20C of the rotation lock portion 20 and the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 overlap in the circumferential direction. On the other hand, when the webbing 12 is pulled out from the spool 14 by moving forward, the spool 14 is rotated in the pull-out direction. Then, the sub-engaging tooth 20C of the rotation lock portion 20 and the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 come into contact with each other in the circumferential direction. Note that FIG. 10A shows a state in which the sub-engaging tooth 20C of the rotation lock portion 20 and the distal end portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 are in contact with each other in the circumferential direction. .

When the webbing 12 is further pulled out from the spool 14 after the sub-engaging tooth 20C of the rotation lock portion 20 and the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 come into contact with each other in the circumferential direction, the spool 14 is further rotated in the pull-out direction. Then, as shown in FIGS. 11A and 11B, the rotation lock portion 20 is further tilted toward the fixed lock portion 22 side, and the main engaging teeth 20B of the rotation lock portion 20 move toward the first fixed lock portion 30. contact the terminal end portion 30C of the main engaged tooth 30A. In this state, rotation of the spool 14 in the pull-out direction is locked, and pull-out of the webbing 12 from the spool 14 is restricted. As a result, the body of the occupant is restrained by the webbing 12 .

Here, when the webbing 12 is suddenly pulled out from the spool 14 in the case where a failure occurs such that the coil portion 36 cannot be energized or the ignition is turned off (when the coil portion 36 is not energized), the rotation lock portion The rotation lock portion 20 is displaced toward the fixed lock portion 22 due to the inertial force caused by the rotation of the rotation lock portion 20 about its own rotation center and the centrifugal force acting on the rotation lock portion 20 . Then, as the webbing 12 is further pulled out from the spool 14, the rotation lock portion 20 (the main engaging tooth 20B and the sub-engaging tooth 20C) is moved to the fixed lock portion 22 (the main engaged tooth of the first fixed lock portion 30). 30A and the sub-engaged teeth 32A) of the second fixed lock portion 32). As a result, the rotation of the spool 14 in the pull-out direction is locked, and the pull-out of the webbing 12 from the spool 14 is restricted. As a result, the occupant's body is restrained by the webbing 12 . As described above, in the present embodiment, the webbing 12 is abruptly pulled out from the spool 14 in the event of an emergency of the vehicle when a failure occurs such that the coil portion 36 cannot be energized or when the ignition is turned off. The body of the occupant can be restrained by the webbing 12 even when the vehicle occupies the seat. If the webbing 12 becomes loose after the occupant's body is restrained by the webbing 12 , the biasing force of the return spring 40 returns (tilts) the rotation lock portion 20 to a position where it does not engage with the fixed lock portion 22 . .

In addition, in the present embodiment, the biasing force of the return spring 40 restricts the tilting of the rotation lock portion 20 toward the fixed lock portion 22 in normal times other than in an emergency of the vehicle. As a result, unnecessary engagement of the rotation lock portion 20 with the fixed lock portion 22 is suppressed, and unnecessary locking of the rotation of the spool 14 can be suppressed.

Further, in this embodiment, the rotation lock portion 20 is not displaced by the electromagnet 26, the moving member 42, and the load transmission portion 48 until the engagement between the rotation lock portion 20 and the fixed lock portion 22 is completed. As a result, it is possible to suppress an increase in the size of the electromagnet 26 and the moving member 42 (an increase in the output of the electromagnet). As a result, it is possible to reduce the size of the webbing take-up device provided with the lock mechanism 38 of the present embodiment. Alternatively, the moving member 42 may directly press the rotation lock portion 20 without providing the load transmission portion 48 .

Further, a lock mechanism may be configured by appropriately combining part of the configuration of the lock mechanism 18 described above and part of the configuration of the lock mechanism 38 of the present embodiment.

(Other forms of locking mechanism)
Next, another form of the lock mechanism 50 will be described with reference to FIGS. 12 to 19. FIG. In the lock mechanism 50 of another embodiment, the members and portions corresponding to the lock mechanisms 18 and 38 described above are denoted by the same reference numerals as the members and portions corresponding to the lock mechanisms 18 and 38 described above, and description thereof will be given. may be omitted.

As shown in FIGS. 12 and 13, the lock mechanism 50 of this embodiment includes a first rotation lock portion 52 and a second rotation lock portion 54 instead of the rotation lock portion 20 (see FIG. 2). It is characterized by being

As shown in FIG. 13, the configuration of the first rotation lock portion 52 is similar to that described above, except that it does not have the sub-engagement teeth 20C (see FIG. 2) and that it has an engagement hole 52A. is configured in the same manner as the rotation lock portion 20 of . An engagement hole 52A is formed through the first rotation lock portion 52 in the axial direction on the side opposite to the side on which the main engagement teeth 20B are formed. 52 A of this engagement hole is formed in the shape of an elongated hole in the radial direction, seeing from an axial direction.

As shown in FIG. 12, the second rotation lock portion 54 is formed in a substantially half-moon shape when viewed from the axial direction. The second rotation lock portion 54 is lighter than the first rotation lock portion 52 because it is made of a resin material. A circular support hole 20A is formed through the center of the second rotation lock portion 54 in the axial direction. The second rotation lock portion 54 is fixed to the spool 14 together with the first rotation lock portion 52 via the support pin 28 inserted into the support hole 20A. A sub-engagement tooth 20</b>C that engages with the second fixed lock portion 32 is formed at the end portion of the second rotation lock portion 54 on one side in the circumferential direction (the pull-out direction side). The sub-engaging teeth 20C are formed so that their tips are sharper than the main engaging teeth 20B of the first rotation lock portion 52 when viewed in the axial direction. A permanent magnet 24 is embedded in the second rotation lock portion 54 on the side where the sub-engagement tooth 20C is formed. In addition, in this embodiment, a part of the permanent magnet 24 is exposed on the core portion 34 side of the electromagnet 26 . In addition, on the side of the second rotation lock portion 54 opposite to the side where the sub-engagement tooth 20C is formed, there is an engagement ring formed on the first rotation lock portion 52 that protrudes toward the first rotation lock portion 52 side. A cylindrical engaging protrusion 54A is formed in the joint hole 52A. The engagement protrusion 54A is movable in the engagement hole 52A in the longitudinal direction of the engagement hole 52A, so that the second rotation lock portion 54 can move toward the support pin 28 with respect to the first rotation lock portion 52. It can be tilted (displaced) by a predetermined angle. Further, by tilting the second rotation lock portion 54 with respect to the first rotation lock portion 52, the sub-engagement teeth 20C of the second rotation lock portion 54 form the main engagement teeth 20B in the first rotation lock portion 52. It protrudes radially outwardly with respect to the portion where it is formed.

(Action and effect of the lock mechanism 50 of the present embodiment)
Next, the operation and effects of the lock mechanism 50 of this embodiment will be described.

In the lock mechanism 50 described above, the coil portion 36 is energized in one direction in case of emergency of the vehicle. When the coil portion 36 is energized in one direction, a magnetic force repulsive to the permanent magnet 24 is generated in the core portion 34 . As a result, as shown in FIG. 14, the second rotation lock portion 54 to which the permanent magnet 24 is fixed is tilted with respect to the first rotation lock portion 52, and the sub-engaging teeth 20C of the second rotation lock portion 54 are engaged. protrudes radially outward from the portion of the first rotation lock portion 52 where the main engaging tooth 20B is formed. Here, in the present embodiment, the second rotation lock is extended to the position where the engagement projection 54A of the second rotation lock 54 abuts the radially inner end 52B of the engagement hole 52A of the first rotation lock 52. The portion 54 tilts with respect to the first rotation lock portion 52 .

When the second rotation lock portion 54 tilts with respect to the first rotation lock portion 52, the sub-engaging tooth 20C of the second rotation lock portion 54 and the distal end portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 overlap in the circumferential direction. In this state, when the occupant wearing the webbing 12 (see FIG. 1) moves forward with respect to the vehicle seat, the webbing 12 is pulled out from the spool 14 (see FIG. 1). is rotated to Then, as shown in FIG. 15, the sub-engaging tooth 20C of the second rotation lock portion 54 and the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 come into contact with each other in the circumferential direction.

When the webbing 12 is further pulled out from the spool 14 after the sub-engaging tooth 20C of the second rotation lock portion 54 and the tip portion 32B of the sub-engaged tooth 32A of the second fixed lock portion 32 come into contact with each other in the circumferential direction, The spool 14 is further rotated in the withdrawal direction. Then, as shown in FIGS. 16 and 17, the sub-engaging tooth 20C of the second rotation lock portion 54 moves along the sub-engaged tooth 32A of the second fixed lock portion 32. As shown in FIGS. As a result, the second rotation lock portion 54 is further tilted toward the fixed lock portion 22 side together with the first rotation lock portion 52 , and the main engaging tooth 20 B of the first rotation lock portion 52 is engaged with the main cover of the first fixed lock portion 30 . It moves toward the terminal end 30C of the engaging tooth 30A.

Further, when the webbing 12 is further pulled out from the spool 14, the spool 14 is further rotated in the pull-out direction, and as shown in FIG. 30 contacts the terminal end 30C of the main engaged tooth 30A. In this state, rotation of the spool 14 in the pull-out direction is locked, and pull-out of the webbing 12 from the spool 14 is restricted. As a result, the body of the occupant is restrained by the webbing 12 .

Here, in the present embodiment, the second rotation lock portion 54 is tilted with respect to the first rotation lock portion 52 so that the sub-engagement tooth 20C of the second rotation lock portion 54 is engaged with the main engagement of the first rotation lock portion 52 . It engages with the fixed lock portion 22 (the second fixed lock portion 32) before the mating tooth 20B. As a result, the impact when the rotation lock portions (the first rotation lock portion 52 and the second rotation lock portion 54) engage with the fixed lock portion 22 is dispersed to the first rotation lock portion 52 and the second rotation lock portion 54. can be made As a result, initial impact when the rotation lock portions (the first rotation lock portion 52 and the second rotation lock portion 54) are engaged with the fixed lock portion 22 can be mitigated. As a result, damage to the rotation lock portions (the first rotation lock portion 52 and the second rotation lock portion 54) and the fixed lock portion 22 is suppressed, and the durability of the lock mechanism 50 for locking the rotation of the spool 14 is improved. be able to.

In addition, since the rotation lock portion is divided into the first rotation lock portion 52 and the second rotation lock portion 54, compared to the rotation lock portion 20 described above (see FIG. 2), the first rotation lock portion 52 and the weight of each of the second rotation lock portion 54 can be reduced. Thereby, the kinetic energy of each of the first rotation lock portion 52 and the second rotation lock portion 54 when the spool 14 is rotated can be reduced. As a result, the impact when the second rotation lock portion 54 is engaged with the second fixed lock portion 32 can be reduced, and the first rotation lock portion 52 is engaged with the first fixed lock portion 30. The impact can be mitigated.

In addition, since the impact when the rotation lock portions (the first rotation lock portion 52 and the second rotation lock portion 54) are engaged with the fixed lock portion 22 can be reduced, the first rotation lock portion 52 and the second rotation lock portion 54 each of the engagement teeth (main engagement teeth 20B and sub-engagement teeth 20C) can be sharpened. Thereby, it is possible to suppress rebound of each engaging tooth due to contact of the cutting edge of each engaging tooth (main engaging tooth 20B and sub-engaging tooth 20C). As a result, each of the engaging teeth (the main engaging teeth 20B and the sub-engaging teeth 20C) can be smoothly engaged with the fixed lock portion 22 (the first fixed lock portion 30 and the second fixed lock portion 32). .

Further, in this embodiment, only the second rotation lock portion 54 lighter than the first rotation lock portion 52 is displaced by the electromagnet 26 . As a result, it is possible to suppress an increase in the size of the electromagnet 26 (an increase in the output of the electromagnet). As a result, the size of the webbing take-up device 10 can be reduced.

Further, in this embodiment, the rotation lock portion has a divided structure of the first rotation lock portion 52 and the second rotation lock portion 54 . Accordingly, by appropriately setting the material of the first rotation lock portion 52 and the second rotation lock portion 54 and the dimensions such as thickness in the axial direction, the weight and strength of each can be easily adjusted. Similarly, the first fixed lock portion 30 and the second fixed lock portion 30 and the second fixed lock portion 32 with which the first rotation lock portion 52 and the second rotation lock portion 54 engage, respectively. By selecting the material of the part 32, each weight and strength can be easily adjusted. Note that the first fixed lock portion 30 and the second fixed lock portion 32 may be integrally constructed.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above, and can be implemented in various modifications other than the above without departing from the spirit of the present invention. is of course.

10 webbing take-up device 12 webbing 14 spool 20 rotation lock portion 22 fixed lock portion 24 permanent magnet (restriction portion, displacement portion)
26 electromagnet (restriction part, displacement part)
30 First fixed lock portion 30C Terminal end portion 32 Second fixed lock portion 32B Tip portion 34 Core portion 34A Shaft upper portion 36 Coil portion 40 Return spring (biasing member)
42 moving member 52 first rotation lock portion 54 second rotation lock portion

Claims (15)

a spool on which a webbing worn by an occupant is wound and rotated in a pull-out direction by pulling out the webbing;
a rotation lock portion provided so as to be rotatable integrally with the spool and displaceable in the rotational radial direction of the spool;
a fixed lock portion provided outside the rotation lock portion in the radial direction of rotation of the spool and engaged with the rotation lock portion to lock rotation of the spool in the pull-out direction;
a limiting portion that limits displacement of the rotation lock portion toward the fixed lock portion;
a displacement portion that is actuated in a vehicle emergency to displace the rotation lock portion toward the fixed lock portion against displacement restriction of the rotation lock portion by the restriction portion;
with
When the displacement portion is not operated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion is rotated about its own center of rotation by an inertial force. A webbing take-up device in which the limiting force of the rotation lock portion by the limit portion is adjusted so that the portion is displaced toward the fixed lock portion,
In a normal state of the vehicle except in an emergency, the restricting portion restricts the displacement of the rotation lock portion toward the fixed lock portion so that unnecessary engagement of the rotation lock portion with the fixed lock portion is suppressed. By doing so, the webbing take-up device suppresses unnecessary locking of the rotation of the spool . a permanent magnet fixed to the rotation lock;
an electromagnet formed using a magnetic material and having a core arranged to face the permanent magnet; and a coil arranged around the core;
further comprising
The restricting portion is configured by the permanent magnet and the core portion,
The displacement portion is composed of the permanent magnet and the electromagnet,
The magnetic force of the permanent magnet that attracts the core restricts displacement of the rotation lock portion toward the fixed lock portion,
The webbing winding according to claim 1, wherein the rotation lock portion is displaced toward the fixed lock portion by energizing the coil portion in one direction and generating a magnetic force in the core portion that repels the permanent magnet. pick-up device. 3. A displacement of the rotation lock portion toward the fixed lock portion is restricted by energizing the coil portion in the other direction and generating a magnetic force that attracts the permanent magnet in the core portion. webbing take-up device. When the occupant pulls out the webbing from the spool to wear the webbing, the coil portion is energized in the other direction,
4. The webbing take-up device according to claim 3, wherein the coil portion is de-energized while the webbing is attached to the occupant. The core portion has an upper shaft portion arranged on the rotation shaft of the spool and is provided so as to be rotatable integrally with the spool,
The webbing take-up device according to any one of claims 2 to 4, wherein the coil portion is arranged around the upper portion of the shaft. When the coil portion is energized in one direction, the rotation lock portion is displaced to a position where it can contact the fixed lock portion,
The engagement between the rotation lock portion and the fixed lock portion is completed by rotating the spool in the pull-out direction while the rotation lock portion and the fixed lock portion are in contact with each other. 6. The webbing take-up device according to any one of 5. The fixed lock portion includes a tip portion that contacts the rotation lock portion at the inner portion in the rotation radial direction of the spool, and a terminal end portion that contacts the rotation lock portion at the outer portion in the rotation radial direction of the spool. consists of
The webbing take-up device according to any one of claims 1 to 6, wherein hardness of the tip portion is set lower than hardness of the terminal portion. The fixed lock portion includes a first fixed lock portion and a second fixed lock portion that are arranged adjacent to each other in the rotation axis direction of the spool,
the terminal end portion is provided on the first fixed lock portion;
The webbing take-up device according to claim 7, wherein the tip portion is provided on the second fixed lock portion. The restricting portion includes a biasing member that biases the rotation lock portion in a direction opposite to the fixed lock portion,
The displacement portion includes an electromagnet having a coil portion and a moving member that moves when the coil portion is energized,
When the coil portion is energized in one direction and the moving member moves, the rotation locking portion is directly or indirectly pressed by the moving member, and the rotation locking portion moves toward the fixed locking portion. The webbing take-up device of claim 1, wherein the webbing retractor is displaced to the The rotation lock portion includes a first rotation lock portion and a second rotation lock portion arranged adjacent to the first rotation lock portion along the rotation axis direction of the spool,
The second rotation lock portion is displaceable outward in the rotation radial direction of the spool with respect to the first rotation lock portion,
The second rotation lock portion is displaced to the outside in the rotation radial direction of the spool with respect to the first rotation lock portion, and the second rotation lock portion engages the fixed lock portion earlier than the first rotation lock portion. The webbing take-up device according to any one of claims 1 to 9, which is engaged. a spool on which a webbing worn by an occupant is wound and rotated in a pull-out direction by pulling out the webbing;
a rotation lock portion provided so as to be rotatable integrally with the spool and displaceable in the rotational radial direction of the spool;
a fixed lock portion provided outside the rotation lock portion in the radial direction of rotation of the spool and engaged with the rotation lock portion to lock rotation of the spool in the pull-out direction;
a limiting portion that limits displacement of the rotation lock portion toward the fixed lock portion;
a displacement portion that is actuated in a vehicle emergency to displace the rotation lock portion toward the fixed lock portion against displacement restriction of the rotation lock portion by the restriction portion;
with
When the displacement portion is not operated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion is rotated about its own center of rotation by an inertial force. A webbing take-up device in which the limiting force of the rotation lock portion by the limit portion is adjusted so that the portion is displaced toward the fixed lock portion,
a permanent magnet fixed to the rotation lock;
an electromagnet formed using a magnetic material and having a core arranged to face the permanent magnet; and a coil arranged around the core;
further comprising
The restricting portion is configured by the permanent magnet and the core portion,
The displacement portion is composed of the permanent magnet and the electromagnet,
The magnetic force of the permanent magnet that attracts the core restricts displacement of the rotation lock portion toward the fixed lock portion,
When the coil portion is energized in one direction and a magnetic force repulsive to the permanent magnet is generated in the core portion, the rotation lock portion is displaced toward the fixed lock portion,
The core portion has an upper shaft portion arranged on the rotation shaft of the spool and is provided so as to be rotatable integrally with the spool,
A webbing take-up device in which the coil portion is arranged around the upper portion of the shaft. a spool on which a webbing worn by an occupant is wound and rotated in a pull-out direction by pulling out the webbing;
a rotation lock portion provided so as to be rotatable integrally with the spool and displaceable in the rotational radial direction of the spool;
a fixed lock portion provided outside the rotation lock portion in the radial direction of rotation of the spool and engaged with the rotation lock portion to lock rotation of the spool in the pull-out direction;
a limiting portion that limits displacement of the rotation lock portion toward the fixed lock portion;
a displacement portion that is actuated in a vehicle emergency to displace the rotation lock portion toward the fixed lock portion against displacement restriction of the rotation lock portion by the restriction portion;
with
When the displacement portion is not operated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion is rotated about its own center of rotation by an inertial force. A webbing take-up device in which the limiting force of the rotation lock portion by the limit portion is adjusted so that the portion is displaced toward the fixed lock portion,
The fixed lock portion includes a tip portion that contacts the rotation lock portion at the inner portion in the rotation radial direction of the spool, and a terminal end portion that contacts the rotation lock portion at the outer portion in the rotation radial direction of the spool. consists of
A webbing take-up device in which the hardness of the tip portion is set lower than the hardness of the terminal portion. The fixed lock portion includes a first fixed lock portion and a second fixed lock portion that are arranged adjacent to each other in the rotation axis direction of the spool,
the terminal end portion is provided on the first fixed lock portion;
The webbing take-up device according to claim 12, wherein the tip portion is provided on the second fixed lock portion. a spool on which a webbing worn by an occupant is wound and rotated in a pull-out direction by pulling out the webbing;
a rotation lock portion provided so as to be rotatable integrally with the spool and displaceable in the rotational radial direction of the spool;
a fixed lock portion provided outside the rotation lock portion in the radial direction of rotation of the spool and engaged with the rotation lock portion to lock rotation of the spool in the pull-out direction;
a limiting portion that limits displacement of the rotation lock portion toward the fixed lock portion;
a displacement portion that is actuated in a vehicle emergency to displace the rotation lock portion toward the fixed lock portion against displacement restriction of the rotation lock portion by the restriction portion;
with
When the displacement portion is not operated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock is caused by an inertial force that causes the rotation lock portion to rotate about its own rotation center. A webbing take-up device in which the limiting force of the rotation lock portion by the limit portion is adjusted so that the portion is displaced toward the fixed lock portion,
The restricting portion includes a biasing member that biases the rotation lock portion in a direction opposite to the fixed lock portion,
The displacement portion includes an electromagnet having a coil portion and a moving member that moves when the coil portion is energized,
When the coil portion is energized in one direction and the moving member moves, the rotation locking portion is directly or indirectly pressed by the moving member, and the rotation locking portion moves toward the fixed locking portion. webbing take-up displaced to. a spool on which a webbing worn by an occupant is wound and rotated in a pull-out direction by pulling out the webbing;
a rotation lock portion provided so as to be rotatable integrally with the spool and displaceable in the rotational radial direction of the spool;
a fixed lock portion provided outside the rotation lock portion in the radial direction of rotation of the spool and engaged with the rotation lock portion to lock rotation of the spool in the pull-out direction;
a limiting portion that limits displacement of the rotation lock portion toward the fixed lock portion;
a displacement portion that is actuated in a vehicle emergency to displace the rotation lock portion toward the fixed lock portion against displacement restriction of the rotation lock portion by the restriction portion;
with
When the displacement portion is not operated and the spool is rotated in the pull-out direction at an angular acceleration exceeding a predetermined angular acceleration, the rotation lock portion is rotated about its own center of rotation by an inertial force. A webbing take-up device in which the limiting force of the rotation lock portion by the limit portion is adjusted so that the portion is displaced toward the fixed lock portion,
The rotation lock portion includes a first rotation lock portion and a second rotation lock portion arranged adjacent to the first rotation lock portion along the rotation axis direction of the spool,
The second rotation lock portion is displaceable outward in the rotation radial direction of the spool with respect to the first rotation lock portion,
The second rotation lock portion is displaced to the outside in the rotation radial direction of the spool with respect to the first rotation lock portion, and the second rotation lock portion engages the fixed lock portion earlier than the first rotation lock portion. A webbing take-up device that engages.

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