JP5557367B2 - Seat belt device - Google Patents

Description

  The present invention relates to a seat belt device including an energy absorbing member that relaxes a load that a passenger receives from a webbing during a vehicle collision.

  2. Description of the Related Art Conventionally, a seat belt device for holding a vehicle occupant or the like on a seat includes an emergency lock mechanism that is driven by a sensor that reacts to sudden acceleration, collision, or deceleration to physically lock a webbing drawer. The occupant is restrained effectively and safely. In addition, when the impact force due to the collision is large, when the load acting on the webbing exceeds a predetermined value as a result of the inertial movement of the occupant, the webbing is allowed to be pulled out by a predetermined amount to absorb energy. An energy absorbing mechanism is provided to reduce the burden on the chest of the occupant.

  In the energy absorbing mechanism, a torsion bar is arranged coaxially with a spindle for winding the webbing, and one end of the torsion bar is attached to the spindle, and the other end is attached to the lock member of the emergency lock mechanism. When the emergency lock mechanism is activated, if the load in the webbing pull-out direction acting on the spindle exceeds a predetermined value, the torsion bar causes torsional deformation, allowing the spindle to rotate in the webbing pull-out direction and absorbing impact energy. Do.

  However, if the twisting amount (energy absorption stroke) of the torsion bar is not regulated, in a vehicle having a small vehicle interior space, when the webbing feed amount is excessive, the passenger may cause a so-called secondary collision. is there. For this reason, the thing which provided the stopper member which restrict | limits the twist amount of a torsion bar and regulates the feeding amount of webbing is proposed (for example, refer patent document 1).

  In the retractor described in Patent Document 1, a cylindrical portion extending along the spindle axis direction is provided on the side surface of the disk portion of the tread head facing the end surface of the spindle. The cylindrical portion is attached to the hole of the spindle through which the torsion bar is inserted, and is disposed on the outer peripheral side of the torsion bar. A male screw portion is provided on the outer peripheral surface of the cylindrical portion, and a stopper member is screwed onto the outer peripheral surface.

Accordingly, when the spindle is rotated in the webbing pull-out direction with the disk portion of the tread head fixed to the retractor frame, the stopper member is rotated integrally with the spindle and is screwed into the cylindrical portion. It moves in the axial direction on the outer peripheral surface. At this time, the torsion bar is twisted, but if the stopper member comes into contact with the disk portion of the emergency lock mechanism and cannot be rotated or moved any more, the torsion bar is not twisted any more. Thus, the amount of twist of the torsion bar is limited by the stopper member.
JP 2002-347573 A

  By the way, in the seat belt device, the webbing tension at the time of energy absorption is set according to the vehicle size, the occupant's physique, etc., but there is a case where it is desired to set the webbing tension to increase smoothly just before the end of energy absorption. . However, in the seat belt retractor described in Patent Document 1, when the stopper member comes into contact with the disk portion of the emergency lock mechanism, the twist of the torsion bar is restricted and the webbing tension increases rapidly.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a seat belt device in which the webbing tension immediately before the end of energy absorption can be increased smoothly.

The above object of the present invention is achieved by the following configurations.
(1) a spindle that is rotatably attached to a retractor frame and has a webbing wound around its outer periphery;
A locking member that is rotatable with respect to the retractor frame and that can be fixed in an emergency.
One end in the axial direction is attached to the spindle, the other end in the axial direction is attached to the lock member, and is twisted by a load in the webbing pull-out direction greater than a predetermined value acting on the spindle in the emergency, and the spindle and the lock member A first energy absorbing member that absorbs impact energy by allowing relative rotation with
The spindle is fixed to the spindle so as to rotate integrally with the spindle and to be slidable in the axial direction with respect to the spindle. Coupled, and slides in the axial direction by relative rotation between the spindle and the lock member, restricts the relative rotation by the axial side surface of the lock member, and twists the first energy absorbing member. A seat belt device comprising a regulating member for regulating the amount,
A second energy absorbing member is disposed between the axial end surface of the restricting member and the axial side surface of the lock member, and the second energy absorbing member is the axial end surface of the restricting member or the lock. Located away from the axial side of the member,
When the load in the webbing pull-out direction is applied to the spindle in a state where the rotation of the lock member is blocked, the regulating member moves to the lock member side due to the twist of the first energy absorbing member, In the middle of pulling out, the second energy absorbing member is deformed after coming into contact with the axial end surface of the restricting member and the axial side surface of the locking member to generate webbing tension, and the second energy absorbing member It characterized that after completing the deformation, to stop the movement of the regulating member, the regulating the torsion of the first energy-absorbing member, relative rotation between the locking member and the spindle is stopped A seat belt device.
(2) The second energy absorbing member is an elastic member, and a webbing tension is generated by applying an elastic load generated when the second energy absorbing member is elastically deformed in the axial direction by the movement of the regulating member. (1) The seat belt device according to (1).
(3) The seat belt device according to (2), wherein the elastic member is a metal disc spring.
(4) The seat belt device according to (2), wherein the elastic member is an O-ring made of resin or light metal.
(5) The seat belt device according to (2), wherein the elastic member is a C-shaped member formed by bending a thin steel pipe or a non-ferrous metal pipe.
(6) The second energy absorbing member is a plastic deformation member, and a webbing tension is generated by applying a load by a processing force generated when the second energy absorbing member is plastically deformed in the axial direction. The seat belt device according to (1).
(7) The second energy absorbing member is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member,
At least one of the axial side surface of the lock member and the axial end surface of the restriction member is formed with a guide surface that expands or folds the ring-shaped member by moving the restriction member toward the lock member. The seat belt device according to (6), which is characterized.
(8) The second energy absorbing member is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member,
The seat belt device according to (6), wherein the ring-shaped member is crushed in a bellows shape by the movement of the regulating member.
(9) a spindle that is rotatably attached to the retractor frame and on which the webbing is wound around the outer periphery;
A locking member that is rotatable with respect to the retractor frame and that can be fixed in an emergency.
One end in the axial direction is attached to the spindle, the other end in the axial direction is attached to the lock member, and is twisted by a load in the webbing pull-out direction greater than a predetermined value acting on the spindle in the emergency, and the spindle and the lock member A first energy absorbing member that absorbs impact energy by allowing relative rotation with
The spindle is fixed to the spindle so as to rotate integrally with the spindle and to be slidable in the axial direction with respect to the spindle. Coupled, and slides in the axial direction by relative rotation between the spindle and the lock member, restricts the relative rotation by the axial side surface of the lock member, and twists the first energy absorbing member. A seat belt device comprising a regulating member for regulating the amount,
A second energy absorbing portion protruding toward the lock member is provided on the axial end surface of the restricting member, and the second energy absorbing portion is disposed away from the axial side surface of the lock member,
When the load in the webbing pull-out direction is applied to the spindle in a state where the rotation of the lock member is blocked, the regulating member moves to the lock member side due to the twist of the first energy absorbing member, and the webbing in the course of the drawer, to generate the webbing tension by deformation after said second energy absorbing portion is in contact with the axial side surface of the locking member, after the second energy absorbing portions has completed the deformation, The seat belt device according to claim 1, wherein the movement of the restricting member is stopped to restrict the amount of twist of the first energy absorbing member, and the relative rotation between the spindle and the lock member is stopped.
(10) The second energy absorbing portion is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member,
At least one of the axial side surface of the lock member and the restricting member is provided with a guide surface that expands or folds the second energy absorbing portion by moving the restricting member toward the lock member. The seat belt device according to (9).
(11) The second energy absorbing portion is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member,
The seat belt device according to (9), wherein the second energy absorbing portion is crushed in a bellows shape by the movement of the regulating member.
(12) The regulating member acts on the entire webbing drawer, and the second energy absorbing member or the second energy absorbing part acts from the middle of the webbing withdrawal (1) )-(11) The seatbelt apparatus in any one of. (13) The seatbelt device according to any one of (1) to (12), further including a third energy absorbing member that generates tension on the webbing from the start of the webbing to the predetermined amount. .
(14) The seat belt device according to any one of (1) to (13), wherein the restriction member includes a nut member.

According to the seat belt device of the present invention, the second energy absorbing member is provided between the axial end surface of the regulating member and the axial side surface of the locking member, and the second energy absorbing member is a shaft of the regulating member. When the load in the webbing pull-out direction is applied to the spindle in a state where it is arranged away from the direction end surface or the axial side surface of the lock member and the rotation of the lock member is prevented, the restricting member is caused by the twist of the first energy absorbing member The second energy absorbing member moves to the lock member side, and the second energy absorbing member is deformed after coming into contact with the axial end surface of the regulating member and the axial side surface of the lock member in the middle of pulling out the webbing. after the energy absorbing member has completed deformation, stop the movement of the regulating member, the regulating the torsion of the first energy-absorbing member, the spindle Since the relative rotation between the lock member and the lock member is stopped, the twisting amount of the torsion bar can be restricted by the restricting member, and the webbing tension immediately before the end of energy absorption can be increased smoothly. The degree of freedom in setting the absorption load can be improved.
Further, the seat belt apparatus of the present invention, the axial end surface of the regulating member, the second energy absorbing portion is provided with a projecting locking member, said second energy absorbing portion, the axial side of the locking member When the load in the webbing pull-out direction is applied to the spindle in a state where the lock member is disposed apart and the rotation of the lock member is prevented, the restricting member moves toward the lock member due to the twist of the first energy absorbing member. In the middle of pulling out the webbing, the second energy absorbing part is deformed after contacting the axial side surface of the lock member to generate webbing tension, and the second energy absorbing part is deformed . after completing, stop movement of the regulating member, the regulating the torsion of the first energy-absorbing member, the said spindle locking member By rotating the relative is stopped, it is possible to achieve the same effect as described above.

  Hereinafter, a seat belt device according to each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is an exploded perspective view showing a main part of the seat belt device according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view of the main part of the seat belt device.

  As shown in FIG. 1, a seat belt device 10 includes a retractor frame 11 attached to a vehicle body (not shown), and a substantially cylindrical spindle 13 that is rotatably attached to the retractor frame 11 and has a webbing wound around an outer periphery thereof. A torsion bar 12 which is a first energy absorbing member which is mounted in the spindle 13 and extends along the axial center of the spindle 13 and whose one end in the axial direction is integrally coupled to the spindle 13; And a tread head 15 which is a lock member integrally coupled to the other axial end.

  The retractor frame 11 is obtained by press-molding a metal plate so that left and right side plates 11a and 11b rise from both sides of a back plate 11c fixed to a vehicle body and have a substantially U-shaped cross section. At opposite positions of the left and right side plates 11a and 11b, through holes 11d and 11e are provided in which the torsion bar 12 combined with the spindle 13 is rotatably bridged.

  On the outside of one side plate 11a of the retractor frame 11, a pretensioner (symbol 70 is a pretensioner in FIG. 2) that rotates the spindle 13 in the webbing winding direction so as to remove the slack of the webbing in the event of a vehicle emergency such as a collision. Tension ring) and a winding spring device (not shown) that constantly urges the spindle 13 in the webbing winding direction.

  On the outside of the other side plate 11b of the retractor frame 11, emergency locking means 60 is provided that engages the tread head 15 with the retractor frame 11 to prevent the spindle 13 from rotating in the webbing pull-out direction in the event of a vehicle emergency. The emergency lock unit 60 is equipped with sensors for detecting an emergency of the vehicle, such as a vehicle acceleration detection unit and a webbing pull-out acceleration detection unit.

  The spindle 13 is formed with a housing recess 13a for housing the torsion bar 12 at its center, and a slit 13d into which the end of the webbing is inserted and fixed at a predetermined position in the circumferential direction of the spindle 13. Is provided.

  As shown in FIGS. 1 and 2, the tread head 15 has a disk portion 15a having an axial side surface 15e opposed to the end surface of the spindle 13, and protrudes from the disk portion 15a toward the spindle 13 and has an external thread portion 15c on the outer peripheral surface. And a cylindrical portion 15b formed with a coupling hole 15d of the spindle 13 on the inner peripheral surface. A receiving portion 15f to which a pole 16 as an engaging member is attached is formed on the surface of the disc portion 15a opposite to the side facing the spindle 13. The pole 16 is formed with locking teeth 16a that can be engaged with the internal teeth 11f formed at the peripheral edge of the through hole 11e of the side plate 11b of the retractor frame 11.

  One end in the axial direction of the torsion bar 12 (the end opposite to the tread head 15) is formed with a spindle coupling portion 12a that couples with a coupling hole 13c provided in the housing recess 13a of the spindle 13, and the other axial end of the torsion bar 12 At the (tread head 15 side end), a tread head coupling portion 12b coupled to the coupling hole 15d of the tread head 15 is formed. The spindle coupling portion 12a and the tread head coupling portion 12b have a Torx shape (in which irregularities are formed on the outer periphery, and six irregularities are illustrated in the illustrated example), and the coupling holes 13c of the spindle 13 having a shape corresponding thereto. And the tread head 15 are respectively coupled by being inserted into the coupling holes 15d.

  While the tread head 15 is normally rotatable with respect to the retractor frame 11, the emergency lock means 60 is actuated in the event of a vehicle emergency so that the locking teeth 16 a of the pole 16 are engaged with the internal teeth 11 f of the retractor frame 11. And is fixed to the retractor frame 11. Accordingly, the rotation of the tread head 15 is restricted, and the rotation of the spindle 13 in the webbing pull-out direction is prevented. At this time, when a torque of a predetermined value or more acts between the coupling portions 12a and 12b of the torsion bar 12 due to the load in the pulling direction acting on the webbing, the deformation portion 12c between the coupling portions 12a and 12b is twisted and deformed. By allowing the webbing to be pulled out by a predetermined amount, the impact energy acting on the occupant's body is absorbed.

  The fitting recess 13b formed at the end of the spindle 13 on the tread head 15 side is provided with a regulating member 17 that can rotate integrally with the spindle 13 and slide in the axial direction with respect to the spindle 13. Yes.

  The restricting member 17 is a nut member having a hexagonal outer diameter, for example, and is fixed to a hexagonal fitting recess 13b provided at the tread head side end portion of the spindle 13 so as to slide on the spindle 13. It is movable and can rotate integrally. A female screw portion 17 a is provided on the inner surface of the regulating member 17 and is screwed to the male screw portion 15 c of the tread head 15.

  Further, a metal disc spring 31 which is an elastic member as a second energy absorbing member is disposed between the axial end surface 17b of the regulating member 17 and the axial side surface 15e of the disk portion 15a of the tread head 15. Has been. As shown in FIG. 3, the disc spring 31 has an inner surface larger than the cylindrical portion 15 b of the tread head 15, and has an inclined surface 31 a that inclines radially outward while being curved. The disc spring 31 is elastically deformed in the axial direction by the movement of the regulating member 17 and applies an elastic load generated at that time to the webbing tension.

  In the seat belt apparatus 10 configured as described above, when a sensor (not shown) that detects an emergency of the vehicle is switched, the emergency lock means 60 rotates the pole 16 so that the locking teeth 16a of the pole 16 are moved to the retractor frame 11. The tread head 15 is prevented from rotating. At this time, the spindle 13 is also prevented from rotating in the webbing pull-out direction via the torsion bar 12. For this reason, when the load in the webbing pull-out direction acts on the spindle 13 while the rotation of the tread head 15 is blocked, the webbing tension F (energy absorption load) gradually increases (section A in FIG. 5). ). In this state, as shown in FIG. 4A, the regulating member 17 is screwed to the tip end portion of the cylindrical portion 15b away from the axial side surface 15e of the tread head 15. For this reason, the disc spring 31 is arranged away from the regulating member 17 without elastically deforming.

  When the webbing tension F reaches a predetermined value, the torsion bar 12 is torsionally deformed, and the torsional deformation causes the spindle 13 to rotate relative to the tread head 15 to pull out the webbing, and the webbing tension F is substantially constant. (Section B in FIG. 5). Further, with the torsional deformation of the torsion bar 12, the regulating member 17 and the spindle 13 rotate integrally, and the regulating member 17 is axially moved along the male threaded portion 15 c of the cylindrical portion 15 b of the tread head 15 (tread head 15 To the disk portion 15a). In this section B, the disc spring 31 is sandwiched between the regulating member 17 and the tread head 15 and is not elastically deformed, so that the webbing tension F is substantially constant.

  Further, when the regulating member 17 moves due to the torsion bar 12 torsion and comes into contact with the disc spring 31 brought close to the side surface 15e in the axial direction, the disc spring 31 becomes flat as shown in FIG. It is elastically deformed. The deformation resistance at this time gives a braking force to the movement of the restricting member 17, which is converted into the rotational resistance of the spindle 13 and gradually increases the webbing tension F (section C in FIG. 5). When the restricting member 17 completely crushes the disc spring 31 between the axial side surface 15e of the tread head 15, the restricting member 17 stops rotating and the relative rotation of the spindle 13 with respect to the tread head is restricted. The webbing tension F increases (section D in FIG. 5). For this reason, in this embodiment, the regulating member 17 functions as a stopper member that regulates the relative rotation so as to stop the rotation of the spindle 13.

  As described above, according to the seat belt device 10 of the present embodiment, the metal disc spring 31 is disposed between the axial end surface 17b of the regulating member 17 and the axial side surface 15e of the tread head 15. Therefore, the twisting amount of the torsion bar 12 can be regulated by the regulating member 17 and the webbing tension can be increased just before the end of energy absorption by the torsion bar 12 where the relative rotation between the spindle 13 and the tread head 15 is stopped. It is possible to improve the degree of freedom of setting the energy absorption load with respect to the webbing withdrawal amount.

6 and 7 show a first modification of the present embodiment. In this modification, as shown in FIG. 6, an O-ring 32 made of a resin or light metal such as rubber or elastomer, which is an elastic member, is used as the second energy absorbing member. The inner diameter of the O-ring 32 is formed larger than the outer peripheral surface of the cylindrical portion 15 b of the tread head 15.
Even in such a configuration, as shown in FIG. 7, when the regulating member 17 is rotated and moved by the relative rotation of the spindle 13 and the tread head 15, the O-ring 32 is elastically deformed, and the energy absorption by the torsion bar 12 is performed. The webbing tension can be increased just before the end of.
Other configurations and operations are the same as those in the first embodiment. The cross-sectional shape of the O-ring 32 may be a cross-sectional shape other than the circular cross-section.

8 and 9 show a second modification of the present embodiment. In this modified example, as shown in FIG. 8, a C-shaped member 33 formed by bending a thin steel pipe or a non-ferrous metal pipe, which is an elastic member, is used as the second energy absorbing member. The inner diameter of the C-shaped member 33 is formed larger than the outer peripheral surface of the cylindrical portion 15 b of the tread head 15.
Also in such a configuration, as shown in FIG. 9, the C-shaped member 33 is elastically deformed by the rotation and movement of the regulating member 17 due to the relative rotation of the spindle 13 and the tread head 15, and the energy absorption is completed. The webbing tension can be increased immediately.
Other configurations and operations are the same as those in the first embodiment. The C-shaped member 33 may be made of a high-strength resin member in addition to a small-diameter steel pipe or a non-ferrous metal pipe.

(Second Embodiment)
Next, the seatbelt apparatus 10a which concerns on 2nd Embodiment of this invention is demonstrated based on FIG.10 and FIG.11. FIG. 10 is a partially broken side view showing the tread head and the second energy absorbing member of the present embodiment, and FIG. 11 is a cross-sectional view of the main part showing the state of the second energy absorbing member before energy absorption. It is a figure and (b) is principal part sectional drawing which shows the state after completion | finish of energy absorption. Note that portions that are the same as or equivalent to those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  In 2nd Embodiment, the ring-shaped member 41 which is a plastic deformation member is used as a 2nd energy absorption member. The ring-shaped member 41 is formed by cutting a metal pipe such as steel or light metal, and has an inner diameter larger than the outer peripheral surface of the cylindrical portion 15 b of the tread head 15. Further, a concave portion 15h is formed on the axial side surface 15e of the tread head 15 of this embodiment from the base end of the cylindrical portion 15b to the outer side in the radial direction over the entire circumference. A continuous guide surface 15g is formed over 15h.

In the seat belt device 10 a configured as described above, as shown in FIG. 11, the regulating member 17 is rotated and moved by the relative rotation of the spindle 13 and the tread head 15, so that the ring-shaped member 41 is connected to the tread head 15. It is pressed against the axial side surface 15e and further plastically deformed so as to expand its diameter along the guide surface 15g. Therefore, just before the energy absorption by the torsion bar 12 is finished, it is possible to generate a webbing tension by applying a load by a processing force generated when the ring-shaped member 41 is plastically deformed in the axial direction.
Other configurations and operations are the same as those in the first embodiment. The guide surface can also be provided on the axial end surface 17b of the regulating member 17.

  12 and 13 show a first modification of the present embodiment. In this modification, a guide surface 15i for turning back the ring-shaped member 41 having an enlarged diameter is formed over the entire circumference in addition to the guide surface 15g for expanding the ring-shaped member 41 on the axial side surface 15e of the disk portion 15a. ing.

Even in such a configuration, as shown in FIG. 13, the regulating member 17 is rotated and moved by the relative rotation of the spindle 13 and the tread head 15, so that the ring-shaped member 41 is moved to the axial side surface 15e of the tread head 15. It is pressed and further plastically deformed so as to expand and fold back along the guide surfaces 15g and 15i. Further, in this case, as shown in FIG. 13C, when the regulating member 17 is further moved, the folded ring-shaped member 41 comes into contact with the axial end surface 17b of the regulating member 17 again, so that the webbing tension is added. The Therefore, just before the energy absorption by the torsion bar 12 is finished, it is possible to generate a webbing tension by applying a load by a processing force generated when the ring-shaped member 41 is plastically deformed in the axial direction.
Other configurations and operations are the same as those in the second embodiment.

  14 and 15 show a second example of the present embodiment. In this modification, a ring-shaped member 42 having a bellows shape, which is a plastic deformation member, is used as the second energy absorbing member. The ring-shaped member 42 is made of metal such as steel or light metal, or resin, and has an inner diameter larger than the outer peripheral surface of the cylindrical portion 15b of the tread head 15.

In the seat belt device 10 a configured as described above, as shown in FIG. 15, the regulating member 17 is rotated and moved by the relative rotation of the spindle 13 and the tread head 15, so that the ring-shaped member 42 is connected to the tread head 15. It is pressed against the side surface 15e in the axial direction, is crushed so as to fold the bellows of the ring-shaped member 41, and is plastically deformed. Therefore, just before the end of energy absorption by the torsion bar 12, it is possible to generate a webbing tension by applying a load by the processing force generated when the ring-shaped member 42 is plastically deformed in the axial direction.
Other configurations and operations are the same as those in the second embodiment.

(Third embodiment)
Next, the seatbelt apparatus 10a which concerns on 3rd Embodiment of this invention is demonstrated based on FIG. Note that portions that are the same as or equivalent to those of the second embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  As shown in FIG. 16, in the seatbelt device 10b according to the third embodiment, instead of the second energy absorbing member of the above embodiment, the axial end surface 17b of the regulating member 17 protrudes toward the tread head 15 side. Another cylindrical portion 17c as a second energy absorbing portion is integrally provided. The tread head 15 has the same configuration as that of the second embodiment, and the guide surface 15g formed on the axial side surface 15e faces the tip of the other cylindrical portion 17c.

In the seat belt device 10 b configured as described above, the restriction member 17 is rotated and moved by the relative rotation of the spindle 13 and the tread head 15, so that the other cylindrical portion 17 c of the restriction member 17 is moved in the axial direction of the tread head 15. It is pressed against the side surface 15e and further plastically deformed so as to expand its diameter along the guide surface 15g. Therefore, just before the energy absorption by the torsion bar 12 is completed, it is possible to generate a webbing tension by applying a load by a processing force generated when the other cylindrical portion 17c is plastically deformed in the axial direction. Further, it is not necessary to separately provide the second energy absorbing member, and the number of parts can be reduced.
Other configurations and operations are the same as those in the second embodiment. In addition, you may provide the other cylindrical part as a 2nd energy absorption part in the tread head 15 so that it may protrude in the regulating member side. Further, it is also possible to crush the other cylindrical portion 17c in a bellows shape without providing the guide surfaces 15g and 15i on the axial side surface 15e of the tread head 15.

( Fourth embodiment)
Next, a seat belt device 10d according to a fourth embodiment of the present invention will be described with reference to FIGS. Note that portions that are the same as or equivalent to those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  As shown in FIG. 19, in the seat belt device 10 d according to the fourth embodiment, in addition to the seat belt device 10 of the first embodiment, the drawing of the webbing W is started between one end surface of the spindle 13 and the tread head 15. A bending element 50 as a third energy absorbing member for generating tension on the webbing W until a predetermined amount is pulled out is mounted.

  As shown in FIG. 20, the bending element 50 is a substantially C-shaped wire made of a metal such as stainless steel (SUS), aluminum, or steel. The bending element 50 has an extra length portion 50b that is curved in a U-shape between one end portion 50a that is wide and fixed to the spindle 13 and a first bent portion 50c that contacts the inner surface of the tread head 15. It has become. That is, the bending element 50 does not immediately extend from the one end portion 50a to the other end portion 50f, but once extends to the opposite side to the other end portion 50f side, and makes a U-turn to the first bent portion 50c. Has reached. A curved portion 50d is formed between the first bent portion 50c and the second bent portion 50e. The first bent portion 50c and the second bent portion 50e are located on substantially the same circumference.

  The tread head 15 includes a peripheral wall portion 15k erected on the peripheral edge portion of the disk portion 15a. The peripheral wall portion 15k is fitted by an inlay on the outer peripheral side of one end portion of the spindle 13 to such an extent that it does not interfere with the webbing W that is wound around and pulled out from the spindle 13. A part of the peripheral wall portion 15k (the upper portion in FIG. 19) protrudes toward the outer peripheral side corresponding to the curved portion 50d of the bending element 50. A curved wall 15l that supports the curved portion 50d of the bending element 50 from the inner peripheral side is erected on the disk portion 15a of the tread head 15 on the inner peripheral side of the portion protruding to the outer peripheral side of the peripheral wall portion 15k.

  As shown in FIG. 20, the spindle 13 includes a radial groove 13e extending from a predetermined position on the outer periphery of the spindle 13 to the inner peripheral side, and a circumferential groove 13f extending in the circumferential direction from the bottom of the radial groove 13e. Is provided. The radial groove 13e has a groove width (dimension in the circumferential direction) that is considerably larger than the thickness of the bending element 50.

  One end 50a of the bending element 50 is inserted and fixed in the circumferential groove 13f. The surplus length portion 50b of the bending element 50 is stored in the radial groove 13e, and a space c is formed between the top of the U-shaped surplus length portion 50b and one of the side walls defining the radial groove 13e. Is done. Specifically, among the pair of side walls that define the radial groove 13e, a space c between the rear side wall and the top of the extra length portion 50b of the bending element 50 when viewed from the rotation direction of the spindle 13 when the webbing is pulled out. Is formed.

Next, the operation of this embodiment will be described with reference to FIGS.
When a sensor (not shown) that detects a vehicle emergency is switched, the emergency lock means 60 rotates the pole 16 to engage the locking teeth 16a of the pole 16 with the internal teeth 11f of the retractor base 11, and the tread head. Block 15 rotations. At this time, the spindle 13 is also prevented from rotating in the webbing pull-out direction via the torsion bar 12. However, when the force pulling the webbing W increases, the deformed portion 12c of the torsion bar 12 is twisted, the spindle 13 is rotated, and the webbing W is pulled out (section A in FIG. 22).

  As the torsion bar 12 is twisted, when the spindle 13 is rotated counterclockwise from the state shown in FIG. 20, the space c becomes narrower and the spindle 13 is further rotated. Until the space c disappears as shown in FIG. 21 (a), the bending element 50 is slightly deformed around the one end 50a and the extra length 50b, but the other portions remain stationary together with the tread head 15. It is. The resistance force that suppresses the rotation of the spindle 13 by the bending element 50 during this period is still small. During this time, the spindle 13 rotates by a predetermined amount, so that the static frictional resistance acting on the webbing changes to a dynamic frictional resistance.

  When the spindle 13 is further rotated from the state where the space c has disappeared, the bending element 50 is also rotated together with the spindle 13. At this time, the first bending portion 50c and the second bending portion 50e of the bending element 50 are bent between the peripheral wall portion 15i of the locking device and the spindle 13. Thereby, energy absorption is performed. As the spindle 13 is rotated, the positions of the first bending portion 50c, the bending portion 50d, and the second bending portion 50e of the bending element 50 are different from those of the bending element 50 as shown in FIG. It shifts to the end 50f side. That is, the bending element 50 is plastically deformed. In other words, the bending element 50 is pulled out from between the peripheral wall portion 15k and the curved wall 15l of the stationary locking device. The webbing tension F is added by the energy absorption at this time (section B1 in FIG. 22).

  When the spindle 13 is further rotated, the other end portion 50f of the bending element 50 passes between the peripheral wall portion 15i and the curved wall 15j of the locking device, and finally the state shown in FIG. It reaches. FIG. 21 (c) shows a state in which the spindle 13 has rotated almost once from the initial state shown in FIG. 20. In this state, energy absorption by the bending element 50 is no longer performed, so that the webbing tension F decreases. (Area B2 in FIG. 22), energy absorption by the torsion bar 12 is performed. After that, the transition is the same as in the first embodiment.

  The seat belt device of the present invention is not limited to the above-described embodiments, and can be appropriately modified, improved, and the like, and can be applied in combination within the feasible range.

  For example, in the present embodiment, the female screw portion 17a is formed on the inner peripheral surface of the regulating member 17 and the male screw portion 15c is formed on the outer circumferential surface of the tread head 15, but the regulating member is located on the inner diameter side of the tread head. In this case, a male screw portion may be formed on the outer peripheral surface of the restricting member 17, and a female screw portion may be formed on the inner peripheral surface of the tread head.

It is a disassembled perspective view which shows schematic structure of the seatbelt apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing of a seatbelt apparatus. Sectional drawing of the disc spring which is the 2nd energy absorption member of FIG. 1, (b) is the top view. (A) is principal part sectional drawing which shows the state before energy absorption by the 2nd energy absorption member of FIG. 3, (b) is principal part sectional drawing which shows the state after completion | finish of energy absorption. It is a graph which shows the relationship between the webbing tension | tensile_strength and stroke in 1st Embodiment. The O-ring which is a 2nd energy absorption member based on the 1st modification of 1st Embodiment is shown, (a) is the sectional drawing, (b) is the top view. (A) is principal part sectional drawing which shows the state before energy absorption by the 2nd energy absorption member of FIG. 6, (b) is principal part sectional drawing which shows the state after completion | finish of energy absorption. The C-shaped member which is a 2nd energy absorption member based on the 2nd modification of 1st Embodiment is shown, (a) is the sectional drawing, (b) is the top view. (A) is principal part sectional drawing which shows the state before energy absorption by the 2nd energy absorption member of FIG. 8, (b) is principal part sectional drawing which shows the state after completion | finish of energy absorption. It is the partially broken side view which shows the tread head and the 2nd energy absorption member of the seatbelt apparatus which concerns on 2nd Embodiment of this invention. (A) is principal part sectional drawing which shows the state before energy absorption by the 2nd energy absorption member of FIG. 10, (b) is principal part sectional drawing which shows the state after completion | finish of energy absorption. It is the partially broken side view which shows the tread head and 2nd energy absorption member which concern on the 1st modification of 2nd Embodiment. (A) is a principal part expanded sectional view which shows the state before energy absorption by the 2nd energy absorption member of FIG. 12, (b) is a principal part expanded sectional view which shows the state in the middle of energy absorption, (C) is a principal part expanded sectional view which shows the state after completion | finish of energy absorption. It is sectional drawing of the ring-shaped member which is a 2nd energy absorption member based on the 2nd modification of 2nd Embodiment. (A) is a principal part expanded sectional view which shows the state before energy absorption by the 2nd energy absorption member of FIG. 14, (b) is a principal part expanded sectional view which shows the state after completion | finish of energy absorption. . It is principal part sectional drawing of the seatbelt apparatus which concerns on 3rd Embodiment of this invention. It is sectional drawing of the seatbelt apparatus which concerns on 4th Embodiment of this invention. It is a sectional view taken along line XX-XX in FIG. 17. (A)-(c) is sectional drawing which shows operation | movement of the bending element which is a 3rd energy absorption member. It is a graph which shows the relationship between the webbing tension | tensile_strength and stroke in 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Seat belt apparatus 11 Retractor frame 12 Torsion bar (1st energy absorption member)
13 Spindle 15 Tread head (locking member)
15e Axial side surface 15g, 15i Guide surface 17 Restricting member 17b Axial end surface 17c Other cylindrical portion (second energy absorbing portion)
31 Disc spring (second energy absorbing member)
32 O-ring (second energy absorbing member)
33 C-shaped member (second energy absorbing member)
41, 42 Ring-shaped member (second energy absorbing member)
50 Bending element (third energy absorbing member)
W Webbing

Claims (14)

A spindle that is rotatably attached to the retractor frame, and a webbing is wound around the outer periphery;
A locking member that is rotatable with respect to the retractor frame and that can be fixed in an emergency.
One end in the axial direction is attached to the spindle, the other end in the axial direction is attached to the lock member, and is twisted by a load in the webbing pull-out direction greater than a predetermined value acting on the spindle in the emergency, and the spindle and the lock member A first energy absorbing member that absorbs impact energy by allowing relative rotation with
The spindle is fixed to the spindle so as to rotate integrally with the spindle and to be slidable in the axial direction with respect to the spindle, and the outer peripheral surface or inner peripheral surface is a screw corresponding to the inner peripheral surface or outer peripheral surface of the lock member. Coupled, and slides in the axial direction by relative rotation between the spindle and the lock member, restricts the relative rotation by the axial side surface of the lock member, and twists the first energy absorbing member. A seat belt device comprising a regulating member for regulating the amount,
A second energy absorbing member is disposed between the axial end surface of the restricting member and the axial side surface of the lock member, and the second energy absorbing member is the axial end surface of the restricting member or the lock. Located away from the axial side of the member,
When the load in the webbing pull-out direction is applied to the spindle in a state where the rotation of the lock member is blocked, the regulating member moves to the lock member side due to the twist of the first energy absorbing member, and the webbing In the middle of pulling out, the second energy absorbing member is deformed after coming into contact with the axial end surface of the restricting member and the axial side surface of the locking member to generate webbing tension, and the second energy absorbing member characterized in that after completing the deformation, to stop the movement of the regulating member, the regulating the torsion of the first energy-absorbing member, relative rotation between the locking member and the spindle is stopped A seat belt device.   The second energy absorbing member is an elastic member, and a webbing tension is generated by applying an elastic load generated when the second energy absorbing member is elastically deformed in the axial direction by the movement of the regulating member. The seat belt device according to claim 1.   The seat belt device according to claim 2, wherein the elastic member is a metal disc spring.   The seat belt device according to claim 2, wherein the elastic member is a resin or light metal O-ring.   The seat belt device according to claim 2, wherein the elastic member is a C-shaped member formed by bending a thin steel pipe or a non-ferrous metal pipe.   The second energy absorbing member is a plastic deformation member, and a webbing tension is generated by applying a load by a processing force generated when the second energy absorbing member is plastically deformed in the axial direction. The seat belt device according to 1. The second energy absorbing member is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member;
At least one of the axial side surface of the lock member and the axial end surface of the restriction member is formed with a guide surface that expands or folds the ring-shaped member by moving the restriction member toward the lock member. The seat belt device according to claim 6. The second energy absorbing member is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member;
The seat belt device according to claim 6, wherein the ring-shaped member is crushed in a bellows shape by the movement of the regulating member. A spindle that is rotatably attached to the retractor frame, and a webbing is wound around the outer periphery;
A locking member that is rotatable with respect to the retractor frame and that can be fixed in an emergency.
One end in the axial direction is attached to the spindle, the other end in the axial direction is attached to the lock member, and is twisted by a load in the webbing pull-out direction greater than a predetermined value acting on the spindle in the emergency, and the spindle and the lock member A first energy absorbing member that absorbs impact energy by allowing relative rotation with
The spindle is fixed to the spindle so as to rotate integrally with the spindle and to be slidable in the axial direction with respect to the spindle, and the outer peripheral surface or inner peripheral surface is a screw corresponding to the inner peripheral surface or outer peripheral surface of the lock member. Coupled, and slides in the axial direction by relative rotation between the spindle and the lock member, restricts the relative rotation by the axial side surface of the lock member, and twists the first energy absorbing member. A seat belt device comprising a regulating member for regulating the amount,
A second energy absorbing portion protruding toward the lock member is provided on the axial end surface of the restricting member, and the second energy absorbing portion is disposed away from the axial side surface of the lock member,
When the load in the webbing pull-out direction is applied to the spindle in a state where the rotation of the lock member is blocked, the regulating member moves to the lock member side due to the twist of the first energy absorbing member, and the webbing in the course of the drawer, to generate the webbing tension by deformation after said second energy absorbing portion is in contact with the axial side surface of the locking member, after the second energy absorbing portions has completed the deformation, The seat belt device according to claim 1, wherein the movement of the restricting member is stopped to restrict the amount of twist of the first energy absorbing member, and the relative rotation between the spindle and the lock member is stopped. The second energy absorbing portion is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member;
At least one of the axial side surface of the lock member and the restricting member is provided with a guide surface that expands or folds the second energy absorbing portion by moving the restricting member toward the lock member. The seat belt device according to claim 9. The second energy absorbing portion is a metal ring-shaped member having an inner diameter larger than an outer peripheral surface of the lock member or the regulating member;
The seatbelt device according to claim 9, wherein the second energy absorbing portion is crushed in a bellows shape by the movement of the regulating member.   12. The regulating member acts on the entire webbing drawer, and the second energy absorbing member or the second energy absorbing unit acts from the middle of the webbing drawer. The seat belt device according to any one of the above.   The seatbelt device according to any one of claims 1 to 12, further comprising a third energy absorbing member that generates tension on the webbing from the start of pulling out the webbing to a predetermined amount.   The seat belt device according to claim 1, wherein the restriction member includes a nut member.

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