JP2010115977A - Webbing winding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain deformation of a deforming member when a giving means is actuated without connecting a winding member and the other end side of the deforming member to each other by an energy absorbing member except for the deforming member. <P>SOLUTION: A centrifugal clutch 30 is revolved by centrifugal force and a lock gear 22 and a spool 14 are connected to each other as the lock gear 22, a torsion shaft 20 and the spool 14 are rotated in the winding direction when a pretensioner mechanism 34 is actuated in this webbing winding device 10. Consequently, one end 20A of the torsion shaft 20 is connected to the spool 14, and, at the same time, the other end 20B of the torsion shaft 20 is connected to the spool 14 through the lock gear 22 and the centrifugal clutch 30. Accordingly, it is possible to prevent torsional deformation of the torsion shaft 20 without connecting the other end 20B of the torsion shaft 20 and the spool 14 to each other by the energy absorbing member except for the torsion shaft 20. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a webbing take-up device in which an applying means applies a rotational force in a take-up direction to a take-up member via a deformable member in an emergency of a vehicle.

  As a webbing take-up device, one end of a torsion bar is connected to one end of a take-up drum so as to be integrally rotatable, and a pretensioner mechanism and an emergency lock operation mechanism are provided on the other end of the torsion bar. Yes (see, for example, Patent Document 1).

  In this webbing take-up device, in the event of a vehicle emergency, the pretensioner mechanism is actuated to apply a rotational force in the take-up direction to the other end of the torsion bar, so that the torsion bar and take-up drum move in the take-up direction. As it is rotated, the take-up drum takes up the webbing.

  Furthermore, the emergency lock operation mechanism regulates the rotation of the other end of the torsion bar in the pull-out direction, and a rotational force in the pull-out direction acts on the take-up drum from the occupant via the webbing, so that the torsion bar Is rotated relative to the other end in the pulling direction, the torsion bar is twisted and deformed, and the webbing is allowed to be pulled out from the winding drum.

  Here, in this webbing take-up device, it is assumed that the rotational force in the take-up direction that the pretensioner mechanism applies to the other end of the torsion bar is increased. Alternatively, it is assumed that the load for twisting the torsion bar is reduced in order to reduce the load for allowing the webbing to be pulled out from the winding drum.

  In this case, when the pretensioner mechanism is activated, the torsion bar is rotated relative to the other end in the winding direction with respect to the one end (the one end is rotated relative to the other end in the pulling direction), The torsion bar may be twisted and deformed. Accordingly, when the webbing is allowed to be pulled out from the winding drum, the torsional deformation amount of the torsion bar may be reduced.

Further, in order to prevent the torsion bar from being twisted and deformed when the pretensioner mechanism is operated, the other end of the take-up drum and the other end of the torsion bar are temporarily connected to an energy absorbing member other than the torsion bar. Let's say that In this case, the load for allowing the webbing to be pulled out from the take-up drum is a combination of the load for twisting the torsion bar and the load for deforming the energy absorbing member. End up.
JP 2006-159986 A

  In consideration of the above fact, the present invention suppresses deformation of the deformable member when the applying means is operated without connecting the winding member and the other end of the deformable member by an energy absorbing member other than the deformable member. It is an object to obtain a webbing take-up device that can be used.

  The webbing take-up device according to claim 1, wherein the webbing mounted on a vehicle occupant is taken up by being rotated in the take-up direction, and is wound in the take-out direction by being pulled out. And a deformable member connected to the winding member at one end side so as to be integrally rotatable, and deformable by relative rotation between the one end side and the other end side, and actuated in an emergency of the vehicle to An applying means for applying a rotational force in the winding direction to the other end side, a regulating means for restricting the rotation of the deformable member in the pull-out direction on the other end side in case of an emergency of the vehicle, the winding member and the deformable member Connecting means for connecting the winding member and the other end side of the deformable member so as to be integrally rotatable by centrifugal force when the other end side of the deformable member is rotated, It has.

  The webbing take-up device according to claim 2 is the webbing take-up device according to claim 1, wherein the connecting means is moved by a centrifugal force when the other end side of the deformable member is rotated, so It has a moving member which connects a member and the other end side of the deformation member so that rotation is possible.

  The webbing take-up device according to claim 3 is the webbing take-up device according to claim 2, wherein the connecting means biases the moving member to restrict movement of the moving member due to centrifugal force. Have means.

  In the webbing take-up device according to claim 1, the webbing attached to the vehicle occupant is taken up by rotating the take-up member in the take-up direction, while the webbing is drawn out to draw out the take-up member. Rotated in the direction. Further, one end side of the deformable member is connected to the winding member so as to be integrally rotatable, and the deformable member is deformable by relative rotation between the one end side and the other end side.

  Further, in the event of an emergency of the vehicle, the applying means is operated to apply a rotational force in the winding direction to the other end side of the deformable member. For this reason, the winding member winds up the webbing by rotating the deformable member and the winding member in the winding direction.

  Furthermore, in the event of an emergency of the vehicle, the restricting means restricts the rotation of the deformable member in the pull-out direction on the other end side. For this reason, after the applying means is operated, the rotation of the deformable member in the pull-out direction on the other end side is restricted, and the rotational force in the pull-out direction acts on the winding member from the occupant via the webbing. The deformable member is rotated relative to the other end side in the drawing direction, whereby the deformable member is deformed and the webbing is allowed to be pulled out from the winding member.

  Here, the connecting means provided between the winding member and the other end side of the deformable member is configured such that when the other end side of the deformable member is rotated, the winding member and the other end side of the deformable member are separated by centrifugal force. Are connected so that they can rotate together. For this reason, even if it does not connect the winding member and the other end side of the deformation member with an energy absorbing member other than the deformation member, the deformation of the deformation member can be suppressed when the applying means is operated.

  In the webbing take-up device according to claim 2, the connecting means has a moving member, and when the other end side of the deforming member is rotated, the moving member is moved by centrifugal force, and the winding member and The other end of the deformable member is connected to be integrally rotatable. For this reason, it is possible to connect the winding member and the other end side of the deformable member so as to be integrally rotatable with a simple configuration.

  In the webbing take-up device according to the third aspect, the connecting means has an urging means, and the urging means urges the moving member to limit the movement of the moving member due to the centrifugal force. For this reason, when the other end side of the deforming member is rotated, the moving member can move against the urging force of the urging means by centrifugal force, and the winding member and the other end side of the deforming member rotate integrally. It can be linked as possible. On the other hand, when the other end side of the deforming member is not rotated, the movement of the moving member can be suppressed by the biasing force of the biasing means, and the winding member and the other end side of the deforming member are connected to be integrally rotatable. Can be suppressed.

  FIG. 1 shows a cross-sectional view of a webbing take-up device 10 according to an embodiment of the present invention as seen from the inside in the vehicle width direction, and FIG. It is shown in the side view seen from the side. Further, FIG. 3 shows a main part of the webbing take-up device 10 in a cross-sectional view (cross-sectional view taken along line 3-3 in FIG. 1) as seen from one side in the vehicle front-rear direction. In the drawings, the inner side in the vehicle width direction is indicated by an arrow IN, one side in the vehicle front-rear direction is indicated by an arrow LO, and the upper side is indicated by an arrow UP.

  As shown in FIGS. 1 and 2, the webbing take-up device 10 according to the present embodiment is provided with a frame 12 having a U-shaped cross section, and the frame 12 has a back plate 12A on the inner side in the vehicle width direction. And a leg plate 12B on one side in the vehicle longitudinal direction and a leg plate 12C on the other side in the vehicle longitudinal direction are provided. The frame 12 is fixed to the vehicle at the back plate 12A, whereby the webbing take-up device 10 is installed in the vehicle.

  Between the leg plate 12B and the leg plate 12C of the frame 12, a substantially cylindrical spool 14 as a winding member is rotatably disposed. A long belt-like webbing 16 (belt) is wound on the spool 14 from the base end side, and the webbing 16 extends upward from the frame 12 and is seated on a vehicle seat (not shown). It is attached to. Further, when the spool 14 is rotated in the winding direction (the direction of the arrow A in FIG. 2 and the like), the spool 14 winds up the webbing 16 and the webbing 16 is pulled out from the spool 14 so that the spool 14 is pulled out. It is rotated in the direction (the direction of arrow B in FIG. 2 etc.).

  A torsion shaft 20 as a deforming member (energy absorbing member) constituting the force limiter mechanism 18 is inserted into the spool 14 along the central axis. One end 20A of the torsion shaft 20 on the leg plate 12C side is coupled to the other end of the spool 14 on the leg plate 12C side so as to be integrally rotatable (relatively non-rotatable), and the torsion shaft 20 is rotatable integrally with the spool 14. ing.

  The other end 20B of the torsion shaft 20 on the leg plate 12B side is connected to one side portion 24 on the spool 14 side of the lock gear 22 as a rotating member so as to be integrally rotatable (relatively unrotatable), and the lock gear 22 is connected to the torsion shaft 20. And the spool 14 and the spool 14 are rotatable together.

  One side portion 24 of the lock gear 22 is smaller in diameter than the other side portion 26 of the lock gear 22 opposite to the spool 14, and the one side portion 24 of the lock gear 22 is located on the leg plate 12 B side of the spool 14. Located in the other end.

  Ratchet teeth 26 </ b> A (external teeth) are formed on the entire outer periphery of the other side portion 26 of the lock gear 22, and a substantially circular clutch hole 28 is formed in the center portion of the other side portion 26 of the lock gear 22. Yes.

  As shown in detail in FIG. 3, a predetermined number (two in the present embodiment) of plate-like centrifugal clutches 30 (pawls) as moving members constituting the coupling means are provided on the outer periphery of one side portion 24 of the lock gear 22. The centrifugal clutch 30 is curved along the outer periphery of the one side portion 24 of the lock gear 22. One end of the centrifugal clutch 30 in the circumferential direction (the same direction as the circumferential direction of the lock gear 22 and the spool 14) is rotatably supported by the other side portion 26 of the lock gear 22, and the centrifugal clutch 30 rotates integrally with the lock gear 22. It is made possible and can be rotated radially outward of the lock gear 22 around one end in the circumferential direction.

  A tension coil spring 32 as an urging means constituting a coupling means is bridged between a pair of centrifugal clutches 30 facing each other with one side portion 24 of the lock gear 22 interposed therebetween. One side part 24 is penetrated. The tension coil spring 32 urges the centrifugal clutch 30 toward the one side portion 24 of the lock gear 22, whereby the centrifugal clutch 30 is separated from the inner peripheral surface of the other end of the spool 14.

  As shown in FIGS. 1 and 2, a rack and pinion type pretensioner mechanism 34 is provided on the outside of the leg plate 12 </ b> B of the frame 12 as an applying means.

  The pretensioner mechanism 34 is provided with a pinion 36 as an imparting member, and the pinion 36 is disposed on the opposite side of the lock gear 22 from the spool 14.

  A columnar clutch portion 38 is provided at a portion of the pinion 36 on the lock gear 22 side, and the clutch portion 38 is rotatably accommodated in the clutch hole 28 of the lock gear 22. A predetermined number (five in the present embodiment) of convex portions 38A are formed on the outer periphery of the clutch portion 38, and the predetermined number of convex portions 38A are arranged at equal intervals in the circumferential direction of the clutch portion 38. At the same time, the protruding height is gradually increased as it goes in the drawing direction. Between the outer periphery of the clutch portion 38 and the outer periphery of the clutch hole 28, a cylindrical roller 40 as a clutch member is accommodated in the winding direction side portion of each convex portion 38A.

  A gear 42 is provided on the opposite side of the pinion 36 from the lock gear 22, and pinion teeth 42 </ b> A (external teeth) are formed on the entire outer periphery of the gear 42.

  A cylinder 44 as a housing member is provided below the pinion 36, and the cylinder 44 is disposed along the vertical direction. The cylinder 44 is fixed to the leg plate 12 </ b> B of the frame 12, and the upper end of the cylinder 44 is opened near the lower side of the gear 42 of the pinion 36.

  A lower end (bottom) of the cylinder 44 is communicated with one end of a substantially cylindrical communication tube 46. A gas generator 48 is fixed to the other end of the communication tube 46, and the gas generator 48 closes the other end of the communication tube 46. In the event of an emergency (collision) of the vehicle, the pretensioner mechanism 34 is activated, so that the gas generator 48 instantaneously generates high-pressure gas and supplies it to the lower end in the cylinder 44 through the communication tube 46. Has been made possible.

  A piston 50 as a drive member is provided in the cylinder 44, and the piston 50 is movable in the vertical direction in the cylinder 44. The piston 50 is provided with a rectangular columnar rack 52, and rack teeth 52 </ b> A are formed on the back plate 12 </ b> A side of the rack 52.

  As shown in FIGS. 4 and 5, when the vehicle is in an emergency, the piston 50 receives the pressure of the high-pressure gas supplied from the gas generator 48 to the lower end of the cylinder 44 from the lower side, and the piston 50 is moved upward. The As a result, the rack 52 (rack teeth 52A) of the piston 50 is engaged (engaged) with the gear 42 (pinion teeth 42A) of the pinion 36, and the pinion 36 is rotated in the winding direction.

  As shown in FIG. 2, between the leg plate 12B and the leg plate 12C of the frame 12, a substantially U-shaped bar-shaped lock body 54 as a regulating member constituting the regulating means is rotatably disposed. Are arranged below the spool 14 and on the back plate 12A side.

  A plate-like lock plate 56 as a restricting portion is integrally provided at one end of the lock body 54 on the leg plate 12B side. The lock plate 56 is provided below the other side portion 26 of the lock gear 22 and on the back plate 12A side. Is arranged. A predetermined number (two in the present embodiment) of lock teeth 56A is formed on the lock gear 22 side portion of the lock plate 56, and the lock teeth 56A are separated from the ratchet teeth 26A of the lock gear 22.

  On the opposite side of the pretensioner mechanism 34 from the frame 12, a sensor mechanism (not shown) is provided as a detecting means constituting a restricting means. As shown in FIG. 5, when the vehicle is in an emergency (rapid deceleration), the sensor mechanism rotates the lock body 54 (lock plate 56) to the upper side (lock gear 22 side), so that the lock teeth 56A of the lock plate 56 are obtained. Is engaged (engaged) with the ratchet teeth 26A of the lock gear 22, and the rotation of the lock gear 22 in the pull-out direction is restricted (locked) (the rotation of the lock gear 22 in the winding direction is permitted).

  Next, the operation of the present embodiment will be described.

  In the webbing retractor 10 having the above configuration, as shown in FIG. 5, the lock mechanism 56 (lock plate 56) is rotated upward by the sensor mechanism in the event of an emergency of the vehicle, so that the lock teeth 56A of the lock plate 56 are Engaged with the ratchet teeth 26A of the lock gear 22, the rotation of the lock gear 22 in the pull-out direction is restricted. As a result, the rotation of the torsion shaft 20 and the spool 14 in the pull-out direction is restricted, so that the withdrawal of the webbing 16 from the spool 14 is restricted, and the occupant is restrained by the webbing 16.

  As shown in FIGS. 4 and 5, in the event of a vehicle emergency, the pretensioner mechanism 34 is activated, so that the gas generator 48 instantaneously generates high-pressure gas and the cylinder 44 through the communication tube 46. Supply to the lower end inside. For this reason, the piston 50 receives the pressure of the high-pressure gas from the lower side, and the piston 50 is moved upward. As a result, the rack 52 (rack teeth 52A) of the piston 50 is engaged with the gear 42 (pinion teeth 42A) of the pinion 36, and the pinion 36 is rotated in the winding direction.

  When the pinion 36 is rotated in the winding direction, the roller 40 between the outer periphery of the clutch portion 38 of the pinion 36 and the outer periphery of the clutch hole 28 of the lock gear 22 is rotated by the rotation of the pinion 36 in the winding direction. The convex part 38A of 38 is moved from the winding direction side position to the drawing direction side position. For this reason, the roller 40 is engaged (engaged) between the clutch portion 38 (the convex portion 38A) and the lock gear 22 (the outer peripheral surface of the clutch hole 28), and the lock gear 22 is wound up integrally with the pinion 36. It can be rotated in the direction. As a result, the lock gear 22, the torsion shaft 20 and the spool 14 are rotated in the winding direction integrally with the pinion 36, and the spool 14 winds up the webbing 16, thereby increasing the restraining force of the occupant by the webbing 16.

  When the lock gear 22 is rotated in the winding direction, as shown in FIG. 6, a predetermined number of centrifugal clutches 30 are rotated integrally with the lock gear 22 in the winding direction, and the predetermined number of centrifugal clutches 30 are caused by centrifugal force. The lock gear 22 is rotated radially outward against the urging force of the tension coil spring 32. For this reason, a predetermined number of centrifugal clutches 30 are engaged with the inner peripheral surface of the other end of the spool 14, and the lock gear 22 (the other end 20B of the torsion shaft 20) and the other end of the spool 14 can rotate integrally (relative rotation). Impossible).

  When the operation of the pretensioner mechanism 34 ends and the rotation of the lock gear 22 in the winding direction stops, as shown in FIGS. 3 and 7, the predetermined number of centrifugal clutches 30 rotate in the winding direction. When stopped, a predetermined number of centrifugal clutches 30 are rotated radially inward of the lock gear 22 by the urging force of the tension coil spring 32 (the lock gear 22 is released from rotating radially outward). For this reason, the predetermined number of centrifugal clutches 30 are separated from the inner peripheral surface of the other end of the spool 14 and the connection between the lock gear 22 and the other end of the spool 14 is released, whereby the lock gear 22 (the other end of the torsion shaft 20). 20B) and the spool 14 can be rotated relative to each other.

  Further, as described above, the lock teeth 56A of the lock plate 56 are engaged with the ratchet teeth 26A of the lock gear 22, and the rotation of the lock gear 22 (the other end 20B of the torsion shaft 20) in the pull-out direction is restricted.

  As a result, when a load (rotational force) greater than the force limiter load is applied to the spool 14 via the webbing 16 from the occupant to which the moving force (inertial force or the like) is applied, the force limiter mechanism 18 is activated. The torsion shaft 20 is torsionally deformed (twisted deformation) by rotating the one end 20A relative to the other end 20B in the pulling direction. For this reason, the spool 14 is rotated in the pull-out direction and the pulling of the webbing 16 from the spool 14 is allowed, so that the load acting on the occupant from the webbing 16 is reduced and the kinetic energy of the occupant is absorbed. .

  Here, as described above, when the pretensioner mechanism 34 is operated and the lock gear 22 is rotated in the winding direction, one end 20A of the torsion shaft 20 is only connected to one end of the spool 14 so as to be integrally rotatable. Instead, the other end 20B of the torsion shaft 20 is connected to the other end of the spool 14 via the lock gear 22 and a predetermined number of centrifugal clutches 30 so as to be integrally rotatable.

  For this reason, the torsion shaft 20 is rotated relative to the one end 20A in the winding direction with respect to the other end 20B by the rotational force in the winding direction of the lock gear 22 applied from the piston 50 via the pinion 36 (one end). 20A is rotated relative to the other end 20B in the pull-out direction), and can be prevented from being twisted.

  Thereby, in order to deal with an occupant having a large body weight such as an adult, the pretensioner mechanism 34 increases the rotational force applied to the lock gear 22 (the other end 20B of the torsion shaft 20) in the winding direction, or the child or the elderly In order to deal with passengers having a small body weight, the load for torsional deformation of the torsion shaft 20 is reduced, and the load (force limiter load) for allowing the webbing 16 to be pulled out from the spool 14 is reduced. Even when the pretensioner mechanism 34 is operated, the torsional deformation of the torsion shaft 20 can be prevented.

  Therefore, when the pretensioner mechanism 34 is operated, the spool 14 can sufficiently rotate in the winding direction, and the restraining force of the occupant by the webbing 16 can be sufficiently increased. Further, when the force limiter mechanism 18 is actuated (when the webbing 16 is allowed to be pulled out from the spool 14), it is possible to prevent the torsional deformation of the torsion shaft 20 from being reduced. It can absorb enough energy.

  In addition, the need to connect the spool 14 and the other end 20 </ b> B (lock gear 22) of the torsion shaft 20 with an energy absorbing member other than the torsion shaft 20 can be eliminated. For this reason, it is possible to prevent the load (force limiter load) for allowing the webbing 16 from being pulled out from the spool 14 from being affected by the energy absorbing member.

  Further, the spool 14, the torsion shaft 20, and the lock gear 22 are rotated together in a normal time of the vehicle (except in an emergency). For this reason, a predetermined number of centrifugal clutches 30 are rotated integrally with the spool 14, the torsion shaft 20 and the lock gear 22, and the predetermined number of centrifugal clutches 30 connect the lock gear 22 and the other end of the spool 14 so as to be integrally rotatable. However, there will be no inconvenience.

  Further, the centrifugal clutch 30 is rotatably supported by the lock gear 22 and is urged toward the radially inner side of the lock gear 22 by a tension coil spring 32. For this reason, when the lock gear 22 is rotated, the centrifugal clutch 30 can rotate outward in the radial direction of the lock gear 22 against the urging force of the tension coil spring 32 by centrifugal force, and the spool 14, the lock gear 22, Can be connected so as to be integrally rotatable. On the other hand, when the lock gear 22 is not rotated, the rotation of the centrifugal clutch 30 can be prevented by the urging force of the tension coil spring 32, and the spool 14 and the lock gear 22 can be prevented from being connected. Thereby, the spool 14 and the lock gear 22 can be reliably connected and disconnected with a simple configuration.

  In the present embodiment, the centrifugal clutch 30 and the tension coil spring 32 are provided in the lock gear 22, but the centrifugal clutch 30 and the tension coil spring 32 are provided in the other end 20B side portion of the torsion shaft 20. Also good.

It is sectional drawing seen from the vehicle width direction inner side which shows the webbing winding device which concerns on embodiment of this invention. It is the side view seen from the vehicle front-back direction one side which shows the webbing winding device which concerns on embodiment of this invention. FIG. 8 is a cross-sectional view (cross-sectional view taken along line 3-3 in FIGS. 1 and 7) showing the main part of the webbing retractor according to the embodiment of the present invention as viewed from one side in the vehicle front-rear direction. It is sectional drawing seen from the vehicle width direction inner side which shows the time of the action | operation of the pretensioner mechanism in the webbing retractor which concerns on embodiment of this invention. It is the side view seen from the vehicle front-back direction one side which shows the time of the action | operation of the pretensioner mechanism in the webbing winding device concerning an embodiment of the invention. FIG. 6 is a cross-sectional view (cross-sectional view taken along the line 6-6 in FIG. 4) viewed from one side in the vehicle front-rear direction, illustrating the operation of the pretensioner mechanism in the webbing retractor according to the embodiment of the present invention. It is sectional drawing seen from the vehicle width direction inner side which shows the time of the action | operation of the force limiter mechanism in the webbing winding device concerning an embodiment of the invention.

Explanation of symbols

10 Webbing take-up device 14 Spool (winding member)
16 Webbing 20 Torsion shaft (deformable member)
30 Centrifugal clutch (connecting means, moving member)
32 Tensile coil spring (connecting means, biasing means)
34 Pretensioner mechanism (applying means)
54 Locking body (regulating means)

Claims (3)

A winding member that is wound by rotating a webbing mounted on a vehicle occupant in the winding direction and rotated in the pulling direction by pulling out the webbing;
A deformable member connected to the winding member at one end side so as to be integrally rotatable, and deformable by relative rotation between the one end side and the other end side;
An applying means that is operated in an emergency of the vehicle and applies a rotational force in a winding direction to the other end of the deformable member;
A restricting means for restricting rotation in the pull-out direction on the other end of the deformable member in an emergency of the vehicle;
Provided between the winding member and the other end side of the deformation member, and when the other end side of the deformation member is rotated, the winding member and the other end side of the deformation member are rotated together by centrifugal force. A connecting means for enabling connection;
A webbing take-up device comprising:   The connecting means includes a moving member that is moved by a centrifugal force when the other end side of the deformable member is rotated and connects the winding member and the other end side of the deformable member so as to be integrally rotatable. The webbing take-up device described.   The webbing take-up device according to claim 2, wherein the connecting means includes urging means for urging the moving member to restrict movement of the moving member due to centrifugal force.

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