JP2019166899A - Seat belt device - Google Patents

Abstract

To provide a seat belt device in which a variably restricting range of tension acting on a webbing is widened.SOLUTION: A retractor 2 includes: a spool 21 winding up a webbing 1; a lock wheel 22 rotatably mounted on one side of the spool 21 in an axial direction; a torsion bar 24 of which one end side is rotatably supported integrally with the lock wheel 22, whereas the other end is rotatably supported integrally with the spool 21; a lock wheel locking member 27 inhibiting rotation of the lock wheel 22 under a predetermined condition; a linear member 221 moved in a circumferential direction relative to the spool 21 or the lock wheel 22 in accordance with relative rotation of the spool 21 and the lock wheel 22; pin members 217a, 217b and 217c drawing the linear member 221; a space Sb in which the linear member 221 before being drawn is housed wound-up in a circumferential direction; and a space Sa in which the linear member 221 after being drawn is housed wound-up in a circumferential direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a seat belt device installed in a vehicle such as an automobile.

  The seat belt device is a safety device that protects the occupant by preventing the occupant from jumping out of the seat, and includes a webbing that restrains the occupant to the seat, and a length that allows the webbing to be pulled out by storing part or all of the webbing ( And a retractor capable of adjusting the webbing withdrawal amount).

  The retractor includes an ELR (Emergency Locking Retractor) mechanism that locks the webbing drawer. The ELR mechanism protects the occupant by preventing the occupant from jumping out of the seat by locking the webbing drawer when a large acceleration or deceleration is applied to the vehicle body (for example, when the vehicle collides). is there.

  Further, the retractor is provided with an EA (Energy Absorber) mechanism that limits the tension (webbing tension) acting on the webbing when the ELR mechanism is operated. The EA mechanism allows the webbing to be pulled out so that the webbing tension (the tension of the webbing that restrains the occupant) does not exceed a predetermined value, and the webbing is pulled out from the retractor with the predetermined webbing tension (webbing pull-out). ) To reduce the impact load acting on the occupant by absorbing the kinetic energy in the meantime.

  Further, in recent years, a variable EA mechanism that variably limits the webbing tension has been developed in order to realize various energy absorption characteristics when the ELR mechanism is operated (see, for example, Patent Documents 1-6). The variable EA mechanism is a mechanism in which a separate mechanism (second EA mechanism) is additionally provided in addition to the EA mechanism (first EA mechanism) described above, and the retractor is retracted with a predetermined webbing tension by the first EA mechanism. By further increasing the webbing tension with the second EA mechanism to temporarily increase the webbing tension (to further limit the webbing pull-out), the kinetic energy is further absorbed. The impact load acting on the occupant is further reduced.

JP 2002-53007 A JP 2000-85527 A JP 2002-53008 A Japanese Patent Laid-Open No. 10-258702 Japanese Patent Laid-Open No. 2001-106025 JP 2002-59809 A

  However, in the prior art, the range in which the webbing tension can be increased by the second EA mechanism (webbing withdrawal amount) is shorter than the webbing withdrawal amount drawn by the first EA mechanism. Not enough to realize. For example, in the prior art described in Patent Documents 1-6, due to its configuration, the range from the start of webbing withdrawal after the ELR mechanism is actuated to the rotation of the spool (webbing take-up portion) about one revolution (webbing) The webbing tension can be increased (variable) only by the amount of withdrawal).

  The present invention has been made in view of the above problems, and an object thereof is to widen a range in which the tension acting on the webbing in the seat belt device can be variably limited.

  A seatbelt device according to a first invention for solving the above-mentioned problems is a seatbelt device comprising a webbing for restraining an occupant to a seat and a retractor capable of adjusting a pull-out amount of the webbing. A first rotating body that is rotatably supported by a retractor frame fixed to the web and winds up the webbing, and is disposed on one axial end side of the first rotating body so as to be rotatable on the retractor frame The second rotating body to be supported and one end side in the axial direction are rotatably supported integrally with the second rotating body, and the other end side in the axial direction can be rotated integrally with the first rotating body. A rod-like body to be supported, a locking device for preventing rotation of the second rotating body under a predetermined condition, and relative rotation between the first rotating body and the second rotating body, First The long member moved in the circumferential direction relative to the second rotating body and the long member moved in the circumferential direction by relative rotation of the first rotating body and the second rotating body. An energy absorbing member that contacts the scale member and absorbs rotational energy due to relative rotation between the first rotating body and the second rotating body, and the long member before contacting the energy absorbing member is in the circumferential direction. A first storage space that is wound around and stored in the first storage space, and the second member that is in contact with the energy absorbing member is wound around and stored in the circumferential direction. A storage space is provided.

  The seat belt device according to a second aspect of the present invention is the seat belt device according to the first aspect, wherein the retractor is provided in a circumferential direction with the first storage space and the second storage space separated in the radial direction. And an opening that is provided in the partition and that communicates the first storage space and the second storage space in the radial direction, wherein the energy absorbing member is the opening. It is arrange | positioned in the vicinity of.

  In the seat belt device according to a third aspect of the present invention, in the second aspect of the invention, the energy absorbing member is disposed radially inward of the opening in the opening portion than the extension line of the outer peripheral surface of the partition wall. And

  The seatbelt device according to a fourth aspect of the present invention is the seatbelt device according to any one of the first to third aspects, wherein the retractor includes the first rotating body and the second second body in the first storage space. A moving means for moving the long member moved in the circumferential direction relative to the rotating body to the one side in the axial direction; and a part of the long member in the second storage space on the other side in the axial direction. Holding means for holding, wherein the elongate member is stored in the first storage space and the second storage space so as to overlap in the axial direction.

  The seat belt device according to a fifth invention is the seat belt device according to any one of the first to fourth inventions, wherein the elongate member is a linear member or a belt-like member, and the energy absorbing member is the linear member. It is a rod-shaped member that handles the member or a blade member that cuts the strip-shaped member.

  The seat belt device according to the present invention can widen the range in which the tension acting on the webbing in the seat belt device can be variably limited.

It is a front view which shows the structure of the seatbelt apparatus which concerns on embodiment of this invention. It is a longitudinal section showing a spool and a lock wheel in a seat belt device concerning an embodiment of the present invention. It is a side view which shows the spool in the seatbelt apparatus which concerns on embodiment of this invention. It is a side view which shows the spool in the seatbelt apparatus which concerns on embodiment of this invention. It is explanatory drawing (longitudinal sectional view) which shows the example which changed a part of structure in the seatbelt apparatus which concerns on embodiment of this invention. It is explanatory drawing (partial enlarged view) which shows the example which changed a part of structure in the seatbelt apparatus which concerns on embodiment of this invention. It is explanatory drawing (partial enlarged view) which shows the example which changed a part of structure in the seatbelt apparatus which concerns on embodiment of this invention. It is explanatory drawing (side view of a spool) which shows the example which changed a part of structure in the seatbelt apparatus which concerns on embodiment of this invention. It is explanatory drawing (partial enlarged view) which shows the example which changed a part of structure in the seatbelt apparatus which concerns on embodiment of this invention. It is explanatory drawing (partial enlarged view) which shows the example which changed a part of structure in the seatbelt apparatus which concerns on embodiment of this invention. It is a graph which shows the characteristic of the seatbelt apparatus which concerns on embodiment of this invention.

  Hereinafter, an embodiment of a seat belt device according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the seat belt device according to the present embodiment is a safety device that is mounted on a vehicle such as an automobile and prevents the occupant from jumping out of the seat to protect the occupant, and restrains the occupant to the seat. The webbing 1 is configured to include a retractor 2 that is a winding device capable of adjusting the pull-out amount of the webbing 1.

  In this embodiment, the retractor 2 includes a spool 21 as a first rotating body, a lock wheel 22 as a second rotating body, an ELR wheel 23, and a torsion bar 24 as a rod-shaped body. ing.

  The spool 21 is formed in a substantially cylindrical shape and is rotatably supported by a retractor frame 25 fixed to the vehicle body. The spool 21 has a larger diameter at both ends in the axial direction (vertical direction in FIG. 1) than the portion where the webbing 1 is wound. Hereinafter, the part formed in this large diameter is called the outer end part 211,212.

  As shown in FIGS. 2 and 3A, one (on the left side in FIG. 2) outer end portion 211 is formed in a bottomed cylindrical shape composed of a bottom portion 213 and peripheral walls 214 and 215. A partition wall 216 is provided over the circumferential direction with a part in the radial direction. The partition wall 216 is not formed continuously over the entire circumferential direction of one outer end portion 211 but is formed in a substantially C shape, and the radially inner space Sa separated by the partition wall 216 and the radially outer side. The space Sb communicates in the radial direction through the opening 216a.

  As shown in FIGS. 1 and 2, the lock wheel 22 is formed in a generally disc shape and is disposed on one axial end side (the left side in FIGS. 1 and 2) of the spool 21, and can rotate on the retractor frame 25. It is supported by. The lock wheel 22 is locked when the belt pull-out acceleration detection unit 26 exceeds a predetermined value and when a relative rotational force in the webbing pull-out direction with respect to the ELR wheel 23 is generated on the lock wheel 22. The rotation is prevented by a lock wheel lock member 27 as a device.

  As shown in FIGS. 2 and 3A, the lock wheel 22 has a single linear member 221 that is a long member. The linear member 221 is fixed to a rod-shaped fixing member (holding means) 222 whose one end 221a protrudes from the lock wheel 22 toward the one outer end 211, and the other end 221b is a free end. It is. One end 221 a of the linear member 221 and the fixing member 222 are accommodated in the radially inner space Sa of the one outer end portion 211, and the other end 221 b of the linear member 221 is the diameter of the one outer end portion 211. It is stored in the space Sb on the outer side in the direction. That is, the linear member 221 is wound and housed in the circumferential direction in the hollow portion of the one outer end portion 211, and the radially inner space Sa and the radially outer space Sb via the opening 216a. Is stored.

  Here, a plurality of (three in the present embodiment) energy absorbing members that protrude from the bottom 213 toward the hollow portion (one side in the axial direction) of the outer end 211 are formed on one outer end 211. Pin members 217a, 217b, and 217c are provided. The pin members 217 a, 217 b, and 217 c are arranged in the vicinity of the opening 216 a so as to be spaced apart from each other in the circumferential direction, and the linear member 221 is disposed in the hollow portion of one outer end portion 211 of these pin members 217 a, 217 b. , 217c are stored while being bent in the radial direction.

  The pin members 217 a, 217 b, and 217 c prevent the linear member 221 from being stored in the radially outer space Sb and the circumferential movement of the linear member 221 due to the relative rotation of the spool 21 and the lock wheel 22. In order to prevent this, the outer peripheral surface of the partition wall 216 is disposed so as to be located radially inward of the extended line (see the two-dot chain line in FIG. 3A).

  As shown in FIG. 1, the ELR wheel 23 is formed in a generally disc shape and is disposed on one end side in the axial direction of the lock wheel 22, and is rotatably supported by the retractor frame 25 together with the lock wheel 22. The ELR wheel 23 is configured to be prevented from rotating by the ELR wheel lock member 29 when the vehicle body acceleration detection unit 28 detects that the vehicle body acceleration exceeds a predetermined value.

  The torsion bar 24 is inserted into the spool 21 and supported at one end by the lock wheel 22 in a state where movement in the rotational direction with respect to the lock wheel 22 is restricted (rotatably with the lock wheel 22). The other end is supported by the other outer end 212 of the spool 21 in a state in which movement in the rotational direction is restricted with respect to the outer end 212 (which can rotate integrally with the spool 21). That is, in the retractor 2, a rotational motion (rotational force) is transmitted through the torsion bar 24 between the spool 21 and the lock wheel 22 (and the ELR wheel 23).

  Here, in this embodiment, the ELR mechanism is constituted by the lock wheel 22, the ELR wheel 23, the belt withdrawal acceleration detection unit 26, the lock wheel lock member 27, the vehicle body acceleration detection unit 28, the ELR wheel lock member 29, and the like. The spool 21, the lock wheel 22, the torsion bar 24, the pin members 217a, 217b, 217c, the linear member 221 and the like constitute a variable EA mechanism.

  Hereinafter, the operation of the seat belt device according to the present embodiment will be described.

  First, for example, when a large deceleration is applied to the vehicle, when the vehicle body acceleration detector 28 detects a sudden deceleration of the vehicle, the ELR wheel lock member 29 prevents the ELR wheel 23 from rotating (see FIG. 1). At this time, the occupant tends to move relative to the vehicle body due to inertia, and the kinetic energy acts on the webbing 1 restraining the occupant, and a load in the pulling direction is applied to the webbing 1.

  When a load in the pull-out direction is applied to the webbing 1 in a state where the rotation of the ELR wheel 23 is blocked, this load is transmitted to the lock wheel 22 via the spool 21 and the torsion bar 24, and is transmitted to the lock wheel 22 with respect to the ELR wheel 23. A relative rotational force is generated in the webbing pull-out direction, and the lock wheel lock member 27 prevents the lock wheel 22 from rotating in the webbing pull-out direction.

  As described above, when the rotation of the lock wheel 22 in the webbing pull-out direction is prevented, the one end side supported by the lock wheel 22 is prevented from rotating, while the torsion bar 24 is supported by the spool 21. The end side is maintained in a rotatable state.

  Therefore, when a larger load in the pulling direction is applied to the webbing 1 in a state where the rotation of the ELR wheel 23 and the lock wheel 22 is blocked, this load becomes torque via the spool 21 and is transmitted to the torsion bar 24. Begins to twist.

  When the torsion bar 24 begins to twist, the spool 21 begins to rotate in the webbing pull-out direction, and when the spool 21 begins to rotate, the one end 221a held by the fixing member 222 starts at one end 221a. It starts to move in the circumferential direction in the hollow portion 211 (space Sa on the inner side in the radial direction and space Sb on the outer side in the radial direction) (see FIGS. 3A and 3B).

  At this time, the linear member 221 is accommodated across the radially inner space Sa and the radially outer space Sb while bending in the radial direction so as to sew the pin members 217a, 217b, and 217c. It moves in the circumferential direction from the radially outer space Sb toward the radially inner space Sa, and is handled by the pin members 217a, 217b, and 217c when passing through the opening 216a. That is, the linear member 221 before being handled by the pin members 217a, 217b, and 217c is accommodated in the radially outer space Sb (winding portion before handling) at one outer end 211, whereas The linear member 221 after being handled by the pin members 217a, 217b, and 217c is housed in the radially inner space Sa (winding portion after handling) in one outer end portion 211.

  Note that the pin members 217a, 217b, and 217c are disposed so as to be located radially inward of the extension line of the outer peripheral surface of the partition wall 216 (see the two-dot chain line in FIG. 3A), and thus the linear member 221 is opened. When passing around the portion 216a, the linear member 221 handled by the fixing member 222 and the linear member 221 passing through the space Sa can be prevented from interfering with each other, and unintended energy absorption occurs. Can be prevented.

  Thereafter, when the entire linear member 221 is handled by the pin members 217a, 217b, and 217c and stored in the radially inner space Sa, the linear member 221 stored in the radially outer space Sb disappears, and the wire The resistance due to contact (handling) between the pin-shaped member 221 and the pin members 217a, 217b, and 217c is eliminated. When resistance due to contact (handling) between the linear member 221 and the pin members 217a, 217b, and 217c disappears, only the webbing pull-out restriction by the torsion bar 24 is continued.

  Therefore, according to the seat belt device according to the present embodiment, the torsion bar 24 starts to twist and the spool 21 rotates, and at the same time, the resistance (load) due to the twist of the torsion bar 24 against the rotation of the spool 21 in the webbing pull-out direction. In addition, resistance (load) due to contact (handling) between the linear member 221 and the pin members 217a, 217b, and 217c can be applied.

  As a result, as shown in FIG. 7, after the ELR mechanism is operated, the rotational energy of the spool 21 is sufficiently absorbed, and the webbing 1 is started to be pulled out as compared with the case where the webbing tension is limited only by the torsion bar 24. Thus, the webbing tension can be increased while the spool 21 is rotated about twice. In addition, the dashed-two dotted line shown in FIG. 7 has shown an example of the value at the time of increasing webbing tension | tensile_strength in the range in the conventional technology in the range for about one rotation of a spool.

  That is, according to the seat belt device according to the present embodiment, the range in which the tension acting on the webbing 1 can be variably limited can be widened as compared with the related art. Thus, for example, in the case of a frontal collision of the vehicle, the distance that the occupant moves forward immediately after the collision can be further suppressed, and the position where the occupant is in contact with the inflating airbag can be more seated. It becomes easy to realize control such that the restraining force does not become too large.

  The webbing pull-out restriction due to the contact (handling) between the linear member 221 and the pin members 217a, 217b, and 217c may be set according to the characteristics of the vehicle to be applied (the position of the handle, the structure of the airbag, etc.). .

  For example, if the length of the linear member 221 is shortened, the range in which the webbing tension can be increased (the amount of webbing withdrawal) can be shortened. Conversely, if the length of the linear member 221 is increased, the webbing tension can be increased. The range (webbing pull-out amount) can be increased. That is, the setting of the range in which the webbing tension can be increased (the webbing pull-out amount) can be adjusted by the length of the linear member 221.

  Furthermore, if the linear member 221 is made thinner or less rigid, or if the distance between the pin members 217a, 217b, and 217c is increased, the increase in webbing tension can be reduced and the linear member 221 is made thicker. Alternatively, if the rigidity is increased or the interval between the pin members 217a, 217b, and 217c is reduced, the increase in the webbing tension can be increased.

  The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

  In the embodiment described above, the linear member 221 is wound in the radial direction (vertical direction in FIG. 2) in the hollow portion (the radially inner space Sa and the radially outer space Sb) of one outer end portion 211. As shown in FIG. 4A, the linear member 221 has an axial direction (FIG. 4A) in the hollow portion (the radially inner space Sa and the radially outer space Sb) of one outer end portion 211. Then, it may be wound so as to overlap in the left-right direction).

  At this time, one end 221a of the linear member 221 that is a fixing portion of the linear member 221 with respect to the fixing member 222 is connected to the other axial end side (bottom 213) in the hollow portion (space Sa inside in the radial direction) of one outer end portion 211. The linear member 221 is moved to one end side in the axial direction to the partition wall 216 that contacts when the linear member 221 moves from the radially outer space Sb to the radially inner space Sa. By providing the inclined portion (moving means) 218a for (approaching), the linear member 221 can be easily stacked and stored in the axial direction.

  As a moving means for moving the linear member 221 toward the one axial end side in the radially outer space Sb, as shown in FIG. 4B, a recess provided on one axial end side (left side in FIG. 4B) of the partition wall 216 It may be 218b, or may be a recess 218c provided on one end side in the axial direction (left side in FIG. 4C) of the pin member 217a as shown in FIG. 4C.

  In the above-described embodiment, the linear member 221 is handled in contact with the pin members 217 a, 217 b, and 217 c, so that the rotational energy due to the relative rotation between the spool 21 and the lock wheel 22 is absorbed. 5, 6A and 6B, the belt-like member 223 as the long member is brought into contact with the blade member 224 as the energy absorbing member and is torn, thereby causing relative rotation between the spool 21 and the lock wheel 22. You may make it absorb rotational energy.

  The blade member 224 has a partition wall so as not to hinder the storage of the band-like member 223 in the radially outer space Sb and the circumferential movement of the band-like member 223 accompanying the relative rotation of the spool 21 and the lock wheel 22. It is preferable that the outer peripheral surface of 216 is disposed so as to be located on the radially inner side of the extended line (see the two-dot chain line in FIG. 5). Thereby, when the band-shaped member 223 passes around the opening of the partition wall 216, the band-shaped member 223 that is cut by the blade member 224 and the band-shaped member 223 that passes through the space outside the radial direction (the winding pool part before cutting), Can be prevented, and unintended energy absorption can be prevented.

  Moreover, in embodiment mentioned above, while providing the linear member 221 as an elongate member in the lock wheel 22, as pin member 217a, 217b, 217c as an energy absorption member, and 1st storage space and 2nd storage space, Spaces Sa and Sb are provided in the spool 21 (one outer end 211), and the linear member 221 is brought into contact with the pin members 217a, 217b, and 217c when the spool 21 and the lock wheel 22 rotate relative to each other. Although an example is shown, a linear member 221 as a long member is provided on the spool 21 (one outer end portion 211), and pin members 217a, 217b, and 217c as energy absorbing members, a first storage space, Spaces Sa and Sb as second storage spaces are provided in the lock wheel 22, and the spool 21 and the lock wheel 22 There the linear member 221 pin member 217a upon relative rotation, 217b, may be squeezed in contact with 217c.

  In the above-described embodiment, the space Sb that houses the linear member 221 before being handled by the pin members 217a, 217b, and 217c is disposed on the radially outer side of the hollow portion of the one outer end portion 211, and the pin member 217a. , 217b, 217c, an example is shown in which the space Sa for storing the linear member 221 after being handled is arranged radially inside the hollow portion of the one outer end 211. The pin members 217a, 217b, 217c A space Sb for storing the linear member 221 before being handled is disposed radially inside the hollow portion of one outer end 211, and the linear member 221 after being handled by the pin members 217a, 217b, and 217c is stored. The space Sa to be operated is disposed on the radially outer side of the hollow portion of one outer end portion 211, and the linear member 221 is changed in diameter with relative rotation of the spool 21 and the lock wheel 22. Toward outside to toward (the space Sa disposed from the space Sb arranged in the radial inside toward the radial outside) may be moved in the circumferential direction.

DESCRIPTION OF SYMBOLS 1 Webbing 2 Retractor 21 Spool 22 Lock wheel 23 ELR wheel 24 Torsion bar 25 Retractor frame 26 Belt pull-out acceleration detection part 27 Lock wheel lock member 28 Car body acceleration detection part 29 ELR wheel lock member 211 One outer end part 212 The other end Outer end portion 213 Bottom portion at outer end portion 214 Radial inner circumferential wall at outer end portion 215 Radial outer circumferential wall at outer end portion 216 Bulkhead at outer end portion 216a Separation opening 217a, 217b, 217c Pin member 221 Linear Member 221a One end of the linear member 221b The other end of the linear member 222 Fixed member Sa Space in the radial direction Sb Space in the radial direction

Claims (5)

In a seat belt device comprising a webbing for restraining an occupant to a seat and a retractor capable of adjusting a pull-out amount of the webbing,
The retractor is
A first rotating body that is rotatably supported by a retractor frame fixed to the vehicle body and winds up the webbing;
A second rotating body disposed on one axial end side of the first rotating body and rotatably supported by the retractor frame;
A rod-shaped body whose one axial end is rotatably supported by the second rotating body and whose other axial end is rotatably supported by the first rotating body,
A locking device that prevents rotation of the second rotating body under predetermined conditions;
A long member that is moved in the circumferential direction relative to the first rotating body or the second rotating body by relative rotation between the first rotating body and the second rotating body;
Due to the relative rotation between the first rotating body and the second rotating body, the first rotating body is in contact with the elongated member moved in the circumferential direction by the relative rotation of the first rotating body and the second rotating body An energy absorbing member that absorbs rotational energy;
A first storage space in which the long member before contacting the energy absorbing member is wound and stored in the circumferential direction;
A second storage space that communicates with the first storage space and is wound around and stored in the circumferential direction after the elongate member comes into contact with the energy absorbing member. Seat belt device. The retractor is
A partition provided across the circumferential direction, separating the first storage space and the second storage space in a radial direction;
An opening that is provided in the partition and communicates the first storage space and the second storage space in a radial direction;
With
The seat belt device according to claim 1, wherein the energy absorbing member is disposed in the vicinity of the opening. The seat belt device according to claim 2, wherein the energy absorbing member is disposed radially inward of an extension line of the outer peripheral surface of the partition wall in the opening. The retractor is
Moving means for moving the long member moved in the circumferential direction by relative rotation between the first rotating body and the second rotating body in the first storage space to one side in the axial direction;
A holding means for holding a part of the elongated member on the other side in the axial direction in the second storage space;
The said elongate member is piled up and accommodated in an axial direction in said 1st storage space and said 2nd storage space. The Claim 1 characterized by the above-mentioned. Seat belt device. The long member is a linear member or a strip member,
The seat belt device according to any one of claims 1 to 4, wherein the energy absorbing member is a rod-shaped member that handles the linear member or a blade member that cuts the strip-shaped member.

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