JP6308227B2 - Crew protection device - Google Patents

Description

  The present invention relates to an occupant protection device.

  Patent Document 1 below discloses a technique related to an occupant protection device that is intended to suppress whipping of an occupant during a rear collision of a vehicle (hereinafter abbreviated as “rear collision” as appropriate). Briefly, in this prior art, when the rear impact of the vehicle is predicted, the lumbar support driving device is operated to move the lumbar support to the front of the vehicle and restrain the seated occupant's waist before the occurrence of the rear impact. Trying to. The lumbar support is also disclosed in Patent Document 2 and Patent Document 3 below.

JP 2007-106379 A JP 2000-236984 A JP 2010-179766 A

  Although the prior art disclosed in the above-mentioned Patent Document 1 is also considered to be effective as a countermeasure for suppressing the lashing of a seated occupant during a rear-end collision, the lumbar support position of the lumbar support during normal use can Since it cannot be displaced in the direction, there is room for improvement from the viewpoint of comfort of seated passengers.

  On the other hand, when using a device that can change the support position of the lumbar portion by the lumbar support up and down, if the support position is set to the lower limit position, the seated occupant is more likely to tilt backward at the time of a rear impact, so the head of the seated occupant Can be supported on the headrest at an early timing. For this reason, it is advantageous to set the lumbar support position of the lumbar support to the lower limit position from the viewpoint of reducing the load on the neck of the seated occupant.

  However, since the position of the lumbar support that the seated occupant feels comfortable during normal use varies depending on the seated occupant, the lumbar support position by the lumbar support may not be set to the lower limit position.

  In consideration of the above fact, the present invention allows the headrest of the seated occupant to be supported by the headrest at an earlier timing even when the lumbar support portion is not set at the lower limit position by the lumbar support portion. It is an object to obtain an occupant protection device that can reduce the load on the neck of a seated occupant.

  The occupant protection device according to the first aspect of the present invention is provided in a seat back of a vehicle seat, supports a waist portion of an occupant seated on a seat cushion of the vehicle seat, and is disposed most forward of the seat back. At least the upper limit position and the lower limit position, with the position at which the foremost end portion supports the upper side of the waist portion being the upper limit position in the seat back vertical direction and the position supporting the lower side of the waist portion being the lower limit position in the seat back vertical direction A lumbar support portion that can be displaced between a forward position that presses the waist and a retracted position that is rearward of the seat back relative to the forward position, and the foremost end portion of the lumbar support portion. A displacement mechanism for displacing, a rear impact prediction unit for predicting a rear collision of the vehicle, and the foremost end portion of the lumbar support portion are not at the lower limit position An operation control unit that controls the displacement mechanism so that the foremost end portion is set at the lower limit position and the forward position when a rear collision of the vehicle is predicted by the rear collision prediction unit. Have.

  In addition, the “frontmost end portion disposed at the most front side of the seat back” according to claim 1 refers to a portion disposed at the most front side of the seat back in the entire lumbar support portion, for example, the lumbar support portion. When the shape bulges to the front side of the seat back, the bulging top corresponds to the foremost end portion.

  According to the above configuration, the lumbar support portion supports the lumbar portion of the occupant seated on the seat cushion of the vehicle seat. The foremost part of the lumbar support that is located on the foremost side of the seat back is the upper limit position in the seat back up and down direction that supports the upper side of the waist, and the position that supports the lower side of the waist part The lower limit position of the direction is displaceable at least between an upper limit position and a lower limit position, and is displaceable between a forward position that presses the waist and a retracted position on the rear side of the seat back from the forward position. The foremost end portion of the lumbar support portion is displaced by a displacement mechanism.

  Here, when a rear collision of the vehicle is predicted by the rear impact prediction unit in a state where the front end portion of the lumbar support portion is not at the lower limit position, the front end portion is at the lower limit position by operating the displacement mechanism. Set to forward position. As a result, the part initially supported in the waist of the seated occupant tends to droop toward the back of the seatback due to its own weight, and the lower part of the waist is pressed toward the front of the seat back. For this reason, the upper body of the seated occupant can easily tilt to the rear side of the seatback, and the head of the seated occupant at the time of the rear collision is supported by the headrest at an earlier timing.

  According to a second aspect of the present invention, in the occupant protection device of the present invention, in the configuration according to the first aspect, the lumbar support portion is movable in a seat back vertical direction, and a rear collision of the vehicle is performed by the rear collision prediction unit. The range of motion of the lumbar support portion in the vertical direction of the seat back when the above is predicted is extended to the lower side of the seat back than the range of motion of the lumbar support portion in the vertical direction of the seat back.

  According to the above configuration, when the rear collision of the vehicle is predicted by the rear collision prediction unit, the lumbar support unit always moves to the lower side of the seat back, and the lumbar support position supported by the lumbar support unit can be lowered.

  According to a third aspect of the present invention, in the configuration of the first or second aspect, the occupant protection device of the present invention restrains the upper body of the occupant seated on the seat cushion with a shoulder webbing, and the waist of the occupant is restrained. A three-point seat belt device restrained by a lap webbing, and a pretensioner that operates when a rear collision of the vehicle is predicted by the rear collision prediction unit and applies tension to the shoulder webbing. When the rear collision prediction unit predicts a rear collision of the vehicle when the front end portion of the lumbar support portion is not in the lower limit position, the control unit determines that the front end portion is after the pretensioner is activated. The displacement mechanism is controlled to be set at the lower limit position and at the forward movement position.

  According to the above configuration, the three-point seat belt device restrains the upper body of the occupant seated on the seat cushion with the shoulder webbing and restrains the occupant's waist with the lap webbing. Further, when a rear collision of the vehicle is predicted by the rear collision prediction unit, the pretensioner is activated to apply tension to the shoulder webbing. Thereby, the upper body of the occupant receives a load toward the rear side of the seat back. When the rear collision prediction unit predicts a rear collision when the front end portion of the lumbar support portion is not at the lower limit position, the front end portion is activated by the displacement mechanism after the pretensioner is operated. Is set to the lower limit position and to the forward movement position. As a result, since the upper position of the seated occupant receives a load on the rear side of the seat back, the support position by the lumbar support part is lowered and the lower part of the lower part of the waist of the seated occupant is pressed toward the front side of the seat back. The upper body of the seated occupant is more easily tilted toward the rear side of the seat back.

  The occupant protection device according to a fourth aspect of the present invention is the configuration according to any one of the first to third aspects, wherein the displacement mechanism moves the lumbar support portion up and down in a seat back vertical direction. A mechanism and an advancing / retreating mechanism for moving the foremost end portion in the back-and-forth direction of the seat back, and the operation control unit includes the rear impact prediction unit in a state where the foremost end portion of the lumbar support portion is not in the lower limit position. When the rear-end collision of the vehicle is predicted by the control unit, after the fore-end mechanism is controlled so that the lumbar support part moves to the lower limit of the seat back when the foremost end portion is not disposed at the forward position. The forward / backward mechanism is controlled such that the foremost end portion moves to the forward position on the front side of the seat back, and the foremost end portion is arranged at the forward position. The come the lumbar support section controls the lifting mechanism to move to the movement limit of the seat back lower side.

  According to the above configuration, when the rear collision prediction unit predicts the rear collision of the vehicle when the front end portion of the lumbar support portion is not at the lower limit position, and the front end portion is not disposed at the forward position, the lumbar support After the part moves to the lower limit of the seat back by the lifting mechanism, the foremost end portion moves to the forward position of the seat back by the advance / retreat mechanism. For this reason, after the prediction of the rear collision, the support state of the part that was initially supported by the foremost end part in the waist part of the seated occupant is released at an early timing, and thereafter the lower part of the waist part. Is pressed forward of the seat back. Therefore, after the prediction of the rear collision, it is possible to easily tilt the upper body of the seated occupant toward the rear side of the seat back at an early timing.

  Further, when the rear collision prediction unit predicts the rear collision of the vehicle when the front end portion of the lumbar support portion is not at the lower limit position, the lumbar support portion is moved up and down when the front end portion is disposed at the forward position. To move to the lower limit of the seat back. For this reason, after the prediction of the rear collision, the lower part of the lumbar part is seated while the support state of the part that was initially supported by the foremost part of the seated occupant's waist is released at an early timing. It is pressed to the back front side. Here, since the foremost end portion was disposed at the forward position when the rear collision of the vehicle was predicted, the displacement allowable stroke to the rear side of the seat back of the portion where the support state by the foremost end portion was released in the waist is Earn early. Therefore, after the prediction of the rear collision, it is possible to easily tilt the upper body of the seated occupant toward the rear side of the seat back at an earlier timing.

  As described above, according to the occupant protection device of the present invention, even when the lumbar support position of the lumbar support portion is not set to the lower limit position, the seated occupant's head is more quickly By having the headrest support it, the load on the neck of the seated occupant can be reduced.

1 is a side view schematically showing a vehicle seat to which an occupant protection device according to a first embodiment is applied. It is a schematic diagram which shows the movable structure of the lumbar support part of FIG. 1 by a side view. FIG. 2 (A) shows a state in which the protruding top portions of the lumbar support portion are arranged on the upper side and the rear side. FIG. 2 (B) shows a state in which the protruding top portion of the lumbar support portion is arranged on the upper side and the front side. FIG. 2 (C) shows a state in which the protruding top portion of the lumbar support portion is disposed on the lower side and the rear side. FIG. 2D shows a state in which the protruding top portion of the lumbar support portion is disposed on the lower side and the front side. It is a typical side view for demonstrating the effect | action of 1st Embodiment. FIG. 3A shows a state immediately before a displacement mechanism is activated after a rear collision of the vehicle is predicted. FIG. 3B shows a state after the displacement mechanism is actuated after the rear collision of the vehicle is predicted. It is a typical side view showing a vehicular seat to which an occupant protection device concerning a 2nd embodiment is applied. FIG. 4A shows a state immediately before a displacement mechanism is activated after a rear collision of the vehicle is predicted. FIG. 4B shows a state after the displacement mechanism is operated after the rear collision of the vehicle is predicted. It is a typical side view showing a vehicular seat to which an occupant protection device concerning a 3rd embodiment is applied. FIG. 5A shows a state immediately before the displacement mechanism is activated after a rear-end collision of the vehicle is predicted. FIG. 5B shows a state after the displacement mechanism is actuated after the rear-end collision of the vehicle is predicted.

[First Embodiment]
An occupant protection device according to a first embodiment of the present invention will be described with reference to FIGS. In these drawings, an arrow FR appropriately shown indicates the vehicle front side, and an arrow UP indicates the vehicle upper side.

  FIG. 1 is a schematic side view of a vehicle seat 12 to which an occupant protection device 10 according to this embodiment is applied. The vehicle seat 12 shown in FIG. 1 is a front seat for a driver's seat as an example. As shown in FIG. 1, the vehicle seat 12 includes a seat cushion 14 that supports the buttocks and thighs of the seated occupant P. A seat back 16 that supports the back (including the waist) of the seated occupant P is supported at the rear end of the seat cushion 14. The seat back 16 can be tilted by a reclining mechanism (not shown) provided at a connecting portion with the seat cushion 14. A headrest 18 that supports the head of the seated occupant P is attached to the upper end of the seat back 16. The height of the headrest 18 can be adjusted.

  A metal seat back frame 16 </ b> F serving as a skeleton member of the seat back 16 is disposed in the rear portion inside the seat back 16. The seat back frame 16F includes a pair of left and right side frames 16S extending in the vertical direction of the seat back on both sides of the seat back 16, and an inverted U shape when viewed from the front of the seat back. And an upper frame (not shown). Further, the seat back frame 16F has a seat back up reinforcement (not shown) that connects the upper portions of the left and right side frames 16S in the seat back width direction, and a seat that connects the lower portions of the left and right side frames 16S in the seat back width direction. Back lower reinforcement (not shown).

  A three-point seat belt device 20 is provided corresponding to the vehicle seat 12 described above. The three-point seat belt device 20 includes a webbing 22 for restraining an occupant. One end portion 22A of the webbing 22 is attached to the side portion of the seat cushion 14 on the outer side in the vehicle width direction (the side portion on the back side in FIG. 1) via the anchor plate 24, and the other end portion 22B of the webbing 22 is the webbing. The spool 26S of the winding device 26 is locked. Further, the intermediate portion of the webbing 22 is inserted and folded through a shoulder anchor 28 provided on the upper side of the vehicle side portion. Further, a buckle device 30 is erected on the side portion (side surface portion shown in FIG. 1) of the seat cushion 14 on the inner side in the vehicle width direction. The buckle device 30 can be engaged with a tongue plate 32 that is supported while being inserted through the intermediate portion of the webbing 22.

  The three-point seat belt device 20 is configured such that the webbing 22 is seated on the seated occupant P (the occupant seated on the seat cushion 14) by engaging the tongue plate 32 with the buckle device 30 while the occupant is seated on the seat cushion 14. It comes to be installed. With the tongue plate 32 engaged with the buckle device 30, the webbing 22 from the tongue plate 32 to the anchor plate 24 is a lap webbing 22X, and the webbing 22 from the tongue plate 32 to the shoulder anchor 28 is a shoulder webbing 22Y. The The lap webbing 22X restrains the waist of the seated occupant P, and the shoulder webbing 22Y restrains the upper body of the seated occupant P.

  The webbing take-up device 26 is fixed near the lower end of a center pillar (not shown) that constitutes the vehicle skeleton member. The spool 26S of the webbing take-up device 26 is arranged so that the axial direction of the spool 26S faces the vehicle front-rear direction. An urging mechanism 26F is disposed on one side of the spool 26S (the vehicle rear side). The spool 26S is constantly urged in the winding rotation direction of the webbing 22 by the urging mechanism 26F.

  Further, the webbing take-up device 26 includes a pretensioner 34. The pretensioner 34 includes a motor 34A disposed on the other side (the vehicle front side) of the spool 26S. The motor 34A rotates to drive the spool 26S in the winding direction. An ECU 36 mounted on the vehicle is electrically connected to the motor 34A.

  The ECU 36 includes an operation control unit 36A, a rear collision prediction unit 36B, and a storage unit 36M. A rear collision prediction PCS (pre-crash safety) sensor 38 is electrically connected to the rear collision prediction unit 36B. The PCS sensor 38 is configured to include a distance sensor such as a millimeter wave radar, and outputs a signal corresponding to the relative distance to the rear vehicle (monitored object) located behind the host vehicle to the rear collision prediction unit 36B. It is supposed to be. Further, the rear collision prediction unit 36B predicts a rear collision (collision between the host vehicle and the rear vehicle) based on the output signal of the PCS sensor 38. Then, the operation control unit 36A operates the motor 34A of the pretensioner 34 to rotate the spool 26S in the winding direction of the webbing 22 when the rear collision prediction of the vehicle is predicted by the rear collision prediction unit 36B. A tension is applied to the webbing 22Y.

  The case where the rear collision prediction unit 36B predicts the rear collision of the vehicle includes the case where it is determined that the collision probability is higher than a predetermined threshold, in addition to the case where the collision is determined to be unavoidable. . Although not described in detail, the pretensioner 34 is controlled by the operation control unit 36A so as to operate even during sudden deceleration of the vehicle. Further, the storage unit 36M described above is configured by, for example, a RAM or the like.

  On the other hand, a movable lumbar support device 40 is disposed on the seat back 16 of the vehicle seat 12. The lumbar support device 40 includes a lumbar support portion 42 that supports the lumbar portion of the occupant P seated on the seat cushion 14 of the vehicle seat 12, and a displacement mechanism 44 (displaced in the figure as a block) for displacing the lumbar support portion 42. Are shown).

  The lumbar support portion 42 is built in a range (a middle portion in the width direction of the seat back 16 and the lower side) of the seat back 16 that supports the waist of the seated occupant P, and is configured by a plate-like body. In FIG. 2, the movable structure of the lumbar support portion 42 is shown in a schematic view in a side view. Each component shown in FIG. 2 is illustrated in a simplified or schematic manner. As shown in FIG. 2A, the lumbar support portion 42 has an upper end portion 42A and a lower end portion 42C extending in the seat back vertical direction and the seat back width direction, and the lower end and the lower end portion 42C of the upper end portion 42A. The upper end is connected by the curved portion 42B. The curved portion 42B curves in a convex shape toward the front side of the seat back and extends in the seat back width direction. That is, in the present embodiment, the protruding top portion 42 </ b> X of the curved portion 42 </ b> B is the foremost end portion disposed on the front side of the seat back most in the lumbar support portion 42.

  As shown by a solid line and a two-dot chain line in FIG. 1, the protruding top portion 42 </ b> X of the lumbar support portion 42 can be displaced in the seat back vertical direction. The projecting top portion 42X of the lumbar support portion 42 has a position supporting the upper side of the waist of the seated occupant P as an upper limit position in the seat back vertical direction, and a position supporting the lower side of the waist of the seated occupant P as the seat back vertical direction. The lower limit position is displaceable between the upper limit position and the lower limit position. The upper limit position is the position of the upper movement limit of the movable range of the protruding top portion 42X in the seatback vertical direction, and the lower limit position is the position of the lower movement limit of the movable range of the protruding top portion 42X in the seatback vertical direction. ing. Further, the upper limit position is set to a position lower in the seat back vertical direction than the arrangement position of the center portion in the sheet width direction in the shoulder webbing 22Y.

  Further, as shown in FIGS. 2A to 2D, the protruding top portion 42X of the lumbar support portion 42 can be displaced in the seat back front-rear direction. More specifically, the protruding top portion 42X of the lumbar support portion 42 has a forward position for pressing the waist of the seated occupant (see FIGS. 2B and 2D), and a rear side of the seat back from the forward position. It can be displaced between the retracted position (see FIGS. 2A and 2C). The forward movement position (see FIGS. 2B and 2D) is a position of the front movement limit of the protruding top portion 42X in the front-rear direction of the seat back, and the backward movement position (see FIGS. 2A and 2C). )) Is the position of the rearward movement limit of the protruding top portion 42X in the front-rear direction of the seat back.

  The protruding top portion 42X of the lumbar support portion 42 is displaced by the displacement mechanism 44 between the upper limit position and the lower limit position in the seat back vertical direction (arrow A direction), and between the forward and backward positions. It is displaced in the direction (arrow B direction). As shown in FIG. 2A, the displacement mechanism 44 includes an elevating mechanism 44A that moves the lumbar support portion 42 in the vertical direction of the seat back, and the protruding top portion 42X of the lumbar support portion 42 is arranged in the front-rear direction of the seat back 16. An advance / retreat mechanism 44B is provided.

  The lifting mechanism 44A includes a motor 46 as shown on the upper side in the drawing. The motor 46 is attached to the seat back frame 16F via a bracket or the like (not shown), and includes a motor main body portion 46M and a sensor portion 46S. The motor body 46M is configured to be driven based on a command signal output from the operation control unit 36A (see FIG. 1). The sensor unit 46S includes, for example, a Hall IC, and is configured to output a signal corresponding to the rotation (rotation position) of the output shaft of the motor body 46M to the storage unit 36M (see FIG. 1).

  A feed screw mechanism 48 that converts the rotational movement of the output shaft of the motor main body 46M into a linear movement is connected to the motor main body 46M. The feed screw mechanism 48 is connected to the inner cable 50 </ b> A of the push-pull wire 50. The inner cable 50A is disposed on the rear side of the seat back relative to the lumbar support portion 42, and penetrates the overhanging portion 42D that protrudes from the upper end portion 42A side of the lumbar support portion 42 to the rear side of the seat back. Further, the lower end portion of the inner cable 50A is fixed to a mounting portion 42E that protrudes from the lower end portion 42C side of the lumbar support portion 42 to the seat back rear side.

  On the other hand, the outer cable 50 </ b> B of the push-pull wire 50 is inserted through the inner cable 50 </ b> A so as to be movable, and is fixed to the seat back frame 16 </ b> F via the connecting portion 52. In this schematic diagram, the outer cable 50B is arranged so that the axial center direction is directed to the seat back vertical direction. However, as an example, the outer cable 50B is arranged in an inverted U shape and one end is fixed to the seat back frame 16F. In addition, the other end portion may be disposed near the upper end portion of the lumbar support portion 42.

  Although not shown, a guide mechanism for guiding the lumbar support portion 42 in the seat back vertical direction is provided on each side of the upper end portion 42A and the lower end portion 42C of the lumbar support portion 42. This guide mechanism has a pair of left and right guide wires extending in the vertical direction of the seat back and a C-shape formed on both sides of the upper end portion 42A and the lower end portion 42C of the lumbar support portion 42 through which the guide wires are inserted. And a wire insertion portion. The guide wire is fixed to the seat back frame 16F via a member.

  With the above configuration, the lumbar support portion 42 is displaced in the seat back up and down direction by moving the inner cable 50A according to the rotation of the motor main body 46M (see the direction of arrow A1). In the present embodiment, the seatback vertical range of motion of the lumbar support part 42 in the normal time (except when the rear collision of the vehicle is predicted by the rear collision prediction unit 36B (see FIG. 1)) and the rear The range of motion of the lumbar support part 42 in the vertical direction of the seat back when the rear face collision of the vehicle is predicted by the collision prediction part 36B (see FIG. 1) coincides.

  The advance / retreat mechanism 44B is attached to the lumbar support portion 42 via a bracket or the like (not shown), and is displaced together with the lumbar support portion 42 in the seat back vertical direction. The advance / retreat mechanism 44B includes a motor 56 as shown on the lower side in the figure. The motor 56 includes a motor main body portion 56M and a sensor portion 56S. The motor body 56M is configured to be driven based on a command signal output from the operation control unit 36A (see FIG. 1). The sensor unit 56S includes, for example, a Hall IC, and is configured to output a signal corresponding to the rotation (rotation position) of the output shaft of the motor body 56M to the storage unit 36M (see FIG. 1).

  A feed screw mechanism 58 that converts the rotational motion of the output shaft of the motor main body 56M into a linear motion is connected to the motor main body 56M. The feed screw mechanism 58 is connected to the inner cable 60 </ b> A of the push-pull wire 60. The inner cable 60A is disposed on the outer side in the seat width direction with respect to the curved portion 42B and on the front side of the seat back relative to the upper end portion 42A and the lower end portion 42C of the lumbar support portion 42, and is movably inserted into the outer cable 60B. The outer cable 60B is fixed to the side portion side of the lower end portion 42C of the lumbar support portion 42 via a connecting portion 62, and is arranged such that the axial center direction thereof is directed to the seat back vertical direction. Further, the upper end portion of the inner cable 60A is fixed to a mounting portion 42F that protrudes from the side portion side of the upper end portion 42A of the lumbar support portion 42 to the front side of the seat back.

  With the above configuration, when the inner cable 60A moves according to the rotation of the motor main body 56M (see the direction of arrow A2), the relative position of the upper end portion 42A in the vertical direction of the seat back with respect to the lower end portion 42C of the lumbar support portion 42 is changed. As a result, the amount of protrusion of the curved portion 42B changes. That is, as the motor body 56M rotates, the protruding top portion 42X of the lumbar support portion 42 is displaced in the front-rear direction of the seat back 16.

  In addition, the lumbar support device 40 includes a manual switch (not shown) used when the occupant adjusts the position of the lumbar support portion 42 on the side surface of the seat cushion 14 (see FIG. 1). This manual switch is configured to output a signal corresponding to an operation by the occupant to the ECU 36 (see FIG. 1).

  An ECU 36 (see FIG. 1) is electrically connected to the motors 46 and 56 of the displacement mechanism 44. When the rear collision prediction unit 36B predicts a rear collision of the vehicle with the protruding top portion 42X of the lumbar support portion 42 not in the lower limit position, the operation control unit 36A shown in FIG. The displacement mechanism 44 is controlled as follows. That is, when the protrusion top portion 42X shown in FIG. 2 is not disposed at the forward movement position, the protrusion top portion is controlled after controlling the motor main body portion 46M of the elevating mechanism 44A so that the lumbar support portion 42 moves to the movement limit on the lower side of the seat back. The motor body 56M of the advance / retreat mechanism 44B is controlled so that 42X moves to the forward position on the front side of the seat back, and when the protruding top portion 42X is arranged at the forward position, the lumbar support portion 42 moves below the seat back. The motor main body 46M of the lifting mechanism 44A is controlled so as to move to

  In other words, the operation control unit 36A determines the pretensioner 34 () when the rear collision prediction unit 36B (see FIG. 1) predicts a rear collision of the vehicle with the protruding top portion 42X of the lumbar support unit 42 not in the lower limit position. After the operation shown in FIG. 1, the displacement mechanism 44 is controlled so that the protruding top portion 42 </ b> X is set at the lower limit position and at the advanced position, as shown in FIGS. 2D and 3B.

  Note that the storage unit 36M shown in FIG. 1 stores the signals output from the sensor units 46S and 56S (see FIG. 2A) as the positional information of the protruding top portion 42X of the lumbar support portion 42, and controls the operation. The part 36A determines whether or not the protruding top part 42X of the lumbar support part 42 is not in the lower limit position based on the position information of the protruding top part 42X stored in the storage part 36M. Further, in the present embodiment, the operation control unit 36A is configured when the rear collision prediction unit 36B predicts a rear collision of the vehicle in a state where the protruding top 42X of the lumbar support unit 42 is at the lower limit position and not at the forward movement position. Controls the displacement mechanism 44 so that the protruding top portion 42X moves to the forward position on the front side of the seat back after the pretensioner 34 is actuated.

(Action / Effect)
Next, the operation and effect of the above embodiment will be described.

  In the present embodiment, the lumbar support portion 42 shown in FIG. 1 supports the waist portion of the occupant P seated on the seat cushion 14 of the vehicle seat 12, and the protruding top portion 42X of the lumbar support portion 42 has an upper limit position. It can be displaced between the lower limit position and between the forward position and the reverse position. The protruding top portion 42X of the lumbar support portion 42 is displaced by the displacement mechanism 44 between the upper limit position and the lower limit position and between the forward movement position and the backward movement position. Therefore, the seated occupant P can set the protruding top portion 42X of the lumbar support portion 42 at a comfortable position by operating a manual switch (not shown). The advancing / retreating mechanism 44B shown in FIG. 2 is attached to the lumbar support portion 42. Therefore, when the lumbar support portion 42 is displaced in the seat back vertical direction by the lifting mechanism 44A, the seat back together with the lumbar support portion 42 is provided. Displaces vertically.

  Here, in a state where the protruding top portion 42X of the lumbar support portion 42 is not at the lower limit position, for example, as shown in FIG. 3A, a rear collision prediction unit 36B (see FIG. 1) predicts a rear collision of the vehicle. In such a case, when the displacement mechanism 44 (see FIG. 2) is operated, as shown in FIG. 3 (B), the projecting apex portion 42X is set at the lower limit position and at the advance position. As a result, the part Y1 that was initially supported in the waist of the seated occupant P tends to droop toward the back of the seat back (in the direction of arrow B2) due to its own weight, and the part Y2 below the waist of the seat occupant P is in front of the seat back (in the direction of arrow B1) ). For this reason, since the upper body of the seated occupant P is easily tilted to the rear side of the seat back, the head PH of the seated occupant P can easily approach the headrest 18, and the head PH of the seated occupant P with respect to the headrest 18 at the time of a rear collision. The relative movement amount of decreases. That is, the head PH of the seated occupant P is supported by the headrest 18 at an earlier timing during a rear collision.

  The operation control of the lumbar support part 42 in this embodiment will be described in more detail. A rear collision prediction unit 36B (see FIG. 1) predicts a rear collision of the vehicle with the protruding top part 42X of the lumbar support part 42 not in the lower limit position. In this case, as shown in FIG. 2 (A), when the protruding top portion 42X is not disposed at the forward movement position, the lumbar support portion 42 is moved to the lower limit of the seat back by the lifting mechanism 44A (FIG. 2 ( C)) After that, the protruding top portion 42X of the lumbar support portion 42 is moved to the forward position on the front side of the seat back by the advance / retreat mechanism 44B (see FIGS. 2D and 3B). For this reason, after the prediction of the rear collision, the support state to the projecting top portion 42X of the portion initially supported by the projecting top portion 42X in the waist of the seated occupant is released at an early timing, and thereafter, as shown in FIG. As shown, the lower portion Y2 of the lower back is pressed to the front side of the seat back. Therefore, after the prediction of the rear collision, it is possible to easily tilt the upper body of the seated occupant P toward the seat back rear side at an early timing.

  On the other hand, when a rear collision of the vehicle is predicted by the rear impact prediction unit 36B (see FIG. 1) in a state where the protruding top portion 42X of the lumbar support portion 42 shown in FIG. As shown in FIG. 2B, when the protruding top portion 42X is disposed at the forward movement position, the lumbar support portion 42 is moved to the lower limit of the seat back by the lifting mechanism 44A (see FIG. 2D). For this reason, after the prediction of the rear collision, as shown in FIG. 3, the support state of the portion Y1 that was initially supported by the protruding top 42X in the waist of the seated occupant P is released at an early timing. However, the lower portion Y2 (see FIG. 3B) of the waist is pressed to the front side of the seat back. Here, since the projecting top portion 42X was disposed at the forward position when the rear surface collision of the vehicle was predicted, a displacement allowable stroke to the rear side of the seat back of the portion Y1 in which the support state by the projecting top portion 42X was released at the waist. Can be earned early. Therefore, after the prediction of the rear collision, it is possible to easily tilt the upper body of the seated occupant P toward the rear side of the seat back at an earlier timing.

  On the other hand, in the present embodiment, the three-point seat belt device 20 shown in FIG. 1 restrains the upper body of the occupant P seated on the seat cushion 14 with the shoulder webbing 22Y and restrains the waist of the occupant P with the lap webbing 22X. To do. When the rear collision prediction unit 36B predicts a rear collision of the vehicle, the pretensioner 34 operates to apply tension to the shoulder webbing 22Y. As a result, as shown in FIG. 3A, the upper body of the seated occupant P receives a load F to the rear side of the seat back.

  When the rear collision of the vehicle is predicted by the rear collision prediction unit 36B (see FIG. 1) in a state where the protruding top portion 42X of the lumbar support portion 42 is not at the lower limit position, for example, in the state shown in FIG. In this case, after the pretensioner 34 (see FIG. 1) is actuated, the displacement mechanism 44 (see FIG. 2) is actuated so that the protruding top 42X is at the lower limit position and the forward position as shown in FIG. Is set. Thereby, after the upper body of the seated occupant P receives the load F to the rear side of the seat back, the support position by the lumbar support portion 42 is lowered, and the lower part of the waist of the seated occupant P is moved to the front side of the seat back. Since it is pressed, the upper body of the seated occupant P is more easily tilted to the rear side of the seat back.

  As described above, according to the occupant protection device 10 of the present embodiment, the head of the seated occupant P at the time of a rear collision, even when the lumbar support portion 42 does not support the lower back position. By supporting the PH on the headrest 18 at an earlier timing, the load on the neck of the seated occupant P can be reduced.

  In the present embodiment, when a rear collision of the vehicle is predicted by the rear impact prediction unit 36B in a state where the protruding top portion 42X of the lumbar support portion 42 is at the lower limit position and not at the advance position, the pretensioner 34 ( After the operation of FIG. 1), the projecting top portion 42 </ b> X is moved to the forward position on the front side of the seat back by the displacement mechanism 44.

[Modification of First Embodiment]
Here, a modification of the first embodiment will be described. In this modification, the movable range in the vertical direction of the seat back of the lumbar support portion 42 when the rear collision of the vehicle is predicted by the rear impact prediction portion 36B shown in FIG. It extends to the lower side of the seat back than the movable range in the vertical direction. According to such a modified example, when the rear collision of the vehicle is predicted by the rear collision prediction unit 36B, the lumbar support unit 42 always moves to the lower side of the seat back, and the lumbar support portion 42 supports the waist. Can be lowered.

[Second Embodiment]
Next, an occupant protection device 70 according to a second embodiment of the present invention will be described with reference to FIG. FIG. 4 shows an occupant protection device 70 according to the present embodiment in a schematic side view together with a part of the vehicle seat 12. FIG. 4 (A) shows a state immediately before a displacement mechanism 80 (described later in detail) is activated when a rear collision of the vehicle is predicted, and FIG. The state after the mechanism 80 is activated is shown. As shown in FIG. 4, the occupant protection device 70 includes a lumbar support device 72 instead of the lumbar support device 40 (see FIG. 1). Different from reference). Other configurations are substantially the same as those of the first embodiment. Therefore, components that are substantially the same as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 4A, the lumbar support device 72 includes a lumbar support portion 74 that supports the waist of the occupant P seated on the seat cushion 14 of the vehicle seat 12 and displaces the lumbar support portion 74. The displacement mechanism 80 is provided. Further, the ECU 88 is mounted on the vehicle. The ECU 88 includes an operation control unit 88A, a rear collision prediction unit 36B similar to that of the first embodiment, and a storage unit 88M configured by, for example, a RAM. The operation control unit 88A is substantially the same configuration unit as the operation control unit 36A (see FIG. 1) in the first embodiment, except for points described below.

  The lumbar support portion 74 is built in a range that supports the waist of the seated occupant P in the seat back 16 (intermediate and lower side in the width direction of the seat back 16), and includes an upper air bag 76 and a lower air bag 78. I have. The upper air bag 76 is disposed at a height position that generally corresponds to the upper side of the waist of the seated occupant P, and the lower air bag 78 is disposed at a height position that generally corresponds to the lower side of the waist of the seated occupant P. ing. The upper air bag 76 and the lower air bag 78 are attached to the seat back frame 16 </ b> F, and the lower end portion of the upper air bag 76 is superimposed on the front side of the seat back with respect to the upper end portion of the lower air bag 78.

  As shown in FIGS. 4A and 4B, the upper air bag 76 and the lower air bag 78 are inflated when air (gas) flows into the interior thereof, respectively, and air ( It will be in a contracted state when (gas) flows out. As a result of the state change of the upper air bag 76 and the lower air bag 78 in this way, the lumbar support portion 74 is located at the foremost end portion (reference numeral 74X in FIG. 4A, FIG. In (B), the position supporting the upper side of the waist of the seated occupant P is the upper limit position in the vertical direction of the seat back, and the position supporting the lower side of the waist of the seated occupant P is defined in the vertical direction of the seat back. The lower limit position is displaceable at least between the upper limit position and the lower limit position, and is displaceable between a forward position that presses the waist of the seated occupant P and a retracted position that is behind the seat back from the forward position. .

  On the other hand, the displacement mechanism 80 includes pumps 81 and 82. The pump 81 includes a pump main body part 81P and a sensor part 81S. Similarly, the pump 82 includes a pump main body part 82P and a sensor part 82S. The pump main bodies 81P and 82P are configured to be driven based on a command signal output from the operation control unit 88A. The sensor units 81S and 82S include, for example, a Hall IC, and the sensor unit 81S is configured to output signals to the storage unit 88M according to pressurization and decompression due to the operation of the pump main body unit 81P. The 82S is configured to output a signal corresponding to pressurization and decompression by the operation of the pump main body 82P to the storage unit 88M.

  One end of a first pipe 84A is connected to the pump body 81P, and an upper air bag 76 is connected to the other end of the first pipe 84A. On the other hand, one end of the second pipe 84B is connected to the pump body 82P, and the lower air bag 78 is connected to the other end of the second pipe 84B. A valve 86A is provided in the middle of the flow path of the first pipe 84A, and a valve 86B is similarly provided in the middle of the flow path of the second pipe 84B.

  When the pump body 81P and the valve 86A are operated, the upper air bladder 76 is switched between the inflated state and the contracted state, and when the pump body 82P and the valve 86B are operated, the lower air bag 78 is in the inflated state. Switch to contracted state. Thus, the displacement mechanism 80 is configured to displace the foremost end portions 74X and 74Y of the lumbar support portion 74 by operating the pump body portions 81P and 82P and the valves 86A and 86B.

  The lumbar support device 72 includes a manual switch (not shown) on the side surface of the seat cushion 14 that is used when the occupant adjusts the position of the lumbar support portion 74 as in the first embodiment. This manual switch is configured to output a signal corresponding to an operation by the occupant to the ECU 88.

  An ECU 88 is electrically connected to the pumps 81 and 82 and the valves 86A and 86B. The operation control unit 88A of the ECU 88 causes the rear collision prediction unit 36B to perform a rear surface collision in a state where the foremost end portion of the lumbar support unit 74 is not at the lower limit position (in the state of the reference numeral 74X in FIG. 4A). When the pre-tensioner 34 (see FIG. 1) is operated, the displacement mechanism 80 is set so that the foremost end portion 74X is set at the lower limit position and at the advanced position, as shown in FIG. The pump main body portions 81P and 82P and the valves 86A and 86B are controlled.

  The storage unit 88M stores the signals output from the sensor units 81S and 82S as position information of the foremost end portion of the lumbar support unit 74, and the operation control unit 88A stores the position stored in the storage unit 88M. Based on the information, it is determined whether or not the foremost end portion of the lumbar support portion 74 is not in the lower limit position. In the present embodiment, the operation control unit 88A is configured when the rear collision prediction unit 36B predicts a rear collision of the vehicle in a state where the foremost end portion of the lumbar support unit 74 is at the lower limit position and not at the forward movement position. After the operation of the pretensioner 34 (see FIG. 1), as shown in FIG. 4B, the displacement mechanism 80 is arranged so that the foremost end portion of the lumbar support portion 74 is displaced to the forward position on the seat back front side. To control.

  According to the configuration of the present embodiment, the rear collision prediction unit 36B has predicted the rear collision of the vehicle in a state where the foremost end portion of the lumbar support portion 74 is not at the lower limit position, for example, in the state shown in FIG. In this case, after the pretensioner 34 (see FIG. 1) is operated, the valves 86A and 86B are opened, and the pump body 81P is operated so that air (gas) flows out from the inside of the upper air bag 76. The pump body 82P operates so that air (gas) flows into the air bag 78. As a result, as shown in FIG. 4B, the foremost end portion 74Y is set at the lower limit position and at the forward movement position.

  Even in the configuration of the present embodiment, the headrest PH of the seated occupant P is supported on the headrest 18 at the earlier timing in a rear-end collision even when the lumbar support portion 74 is not set at the lower limit position. By doing so, the load on the neck of the seated occupant P can be reduced.

[Third Embodiment]
Next, an occupant protection device 90 according to a third embodiment of the present invention will be described with reference to FIG. In FIG. 5, an occupant protection device 90 according to the present embodiment is shown in a schematic side view together with a part of the vehicle seat 12. FIG. 5A shows a state immediately before the displacement mechanism 100 (described later in detail) is activated when a rear-end collision of the vehicle is predicted, and FIG. 5B shows a displacement after the rear-end collision of the vehicle is predicted. The state after the mechanism 100 is activated is shown. As shown in FIG. 5, the occupant protection device 90 is different from the second embodiment in that an air bag 96 dedicated to rear collision is provided. Other configurations are substantially the same as those of the second embodiment. Therefore, components substantially the same as those of the second embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 5A, the lumbar support device 92 includes a lumbar support portion 94 that supports the waist of the occupant P seated on the seat cushion 14 of the vehicle seat 12 and displaces the lumbar support portion 94. The displacement mechanism 100 is provided. Moreover, the ECU 104 is mounted on the vehicle. The ECU 104 includes an operation control unit 104A, a rear collision prediction unit 36B similar to those in the first and second embodiments, and a storage unit 88M substantially similar to that in the second embodiment. The operation control unit 104A is substantially the same configuration unit as the operation control unit 88A in the second embodiment, except as described below. Further, a signal corresponding to the operation of a manual switch (not shown) by the occupant is output to the ECU 104 as in the second embodiment.

  The lumbar support portion 94 includes an air bag 96 on the seat back front side of the lower air bag 78 inside the seat back 16. The lumbar support portion 94 has a frontmost end portion that is disposed on the most front side of the seat back by changing the state of the upper air bag 76, the lower air bag 78, and the rear air bag 96 (FIG. 5A). In FIG. 5B, the position supporting the upper side of the waist of the seated occupant P is the upper limit position in the seat back vertical direction, and the position supporting the lower side of the waist of the seated occupant P As a lower limit position in the seat back up and down direction, at least between the upper limit position and the lower limit position and between a forward position that presses the waist of the seated occupant P and a backward position that is behind the seat back relative to the forward position. Displaceable.

  On the other hand, the displacement mechanism 100 includes a pump 83 as shown on the lower side in the figure. The pump 83 includes a pump main body 83P and a sensor unit 83S. The pump body 83P is configured to be driven based on a command signal output from the operation control unit 104A. The sensor unit 83S includes, for example, a Hall IC and the like, and is configured to output a signal corresponding to pressurization and depressurization by the operation of the pump main body unit 83P to the storage unit 88M.

  One end of a third pipe 84C is connected to the pump body 83P, and an air bag 96 is connected to the other end of the third pipe 84C. A valve 86C is provided in the middle of the flow path of the third pipe 84C. By operating the pump body 83P and the valve 86C, the air bag 96 is switched between an inflated state and a contracted state. The displacement mechanism 100 is configured to displace the foremost end portion of the lumbar support portion 94 by operating the pump main body portions 81P, 82P, 83P and the valves 86A, 86B, 86C.

  The ECU 104 is electrically connected to the pump 83 and the valve 86C. The pump body 83P and the valve 86C are set so as not to operate except when the rear collision of the vehicle is predicted by the rear impact prediction unit 36B of the ECU 104.

  The operation control unit 104A predicts a rear collision of the vehicle by the rear collision prediction unit 36B in a state where the foremost end portion of the lumbar support unit 94 is not at the lower limit position (for example, a state at the position of 94X in FIG. 5A). In this case, after the pretensioner 34 (see FIG. 1) is actuated, as shown in FIG. 5B, the pump body of the displacement mechanism 100 is set such that the foremost end portion is set at the lower limit position and at the advanced position. The parts 81P, 82P, 83P and the valves 86A, 86B, 86C are controlled.

  The storage unit 88M stores the signals output from the sensor units 81S, 82S, and 83S as position information of the foremost end portion of the lumbar support unit 94, and the operation control unit 104A is stored in the storage unit 88M. Based on the position information, it is determined whether or not the foremost end portion of the lumbar support portion 94 is not in the lower limit position. Further, in the present embodiment, the operation control unit 104 </ b> A is used when the rear collision prediction unit 36 </ b> B predicts a rear collision of the vehicle in a state where the foremost end portion of the lumbar support unit 94 is at the lower limit position and not at the forward movement position. Controls the displacement mechanism 100 so that the foremost end portion of the lumbar support portion 94 is displaced to the forward position on the front side of the seat back after the pretensioner 34 (see FIG. 1) is actuated.

  According to the configuration of the present embodiment, a rear collision of the vehicle is predicted by the rear impact prediction unit 36B in a state where the foremost end portion of the lumbar support portion 94 is not at the lower limit position, for example, as shown in FIG. In this case, after the pretensioner 34 (see FIG. 1) is operated, the valves 86A, 86B, 86C are opened, and the pump body 81P is operated so that air (gas) flows out from the upper air bag 76. The pump main bodies 82P and 83P operate so that air (gas) flows into the lower air bag 78 and the air bag 96 dedicated to rear impact. As a result, as shown in FIG. 5B, the foremost end portion 94Y is set at the lower limit position and at the forward movement position.

  Even in the configuration of the present embodiment, the headrest PH of the seated occupant P is supported on the headrest 18 at the earlier timing even in the case of the rear collision even when the lumbar support portion 94 does not support the lower back position. By doing so, the load on the neck of the seated occupant P can be reduced. Further, in this embodiment, since the air bag 96 dedicated to the rear impact is inflated in addition to the lower air bag 78 when the rear collision is predicted, the amount of displacement of the seat occupant P on the lower side of the lower back of the seated occupant P is reduced. It becomes possible to increase. This makes it easier for the seated occupant P to tilt during a rear-end collision.

[Supplementary explanation of the embodiment]
In the first embodiment, the advance / retreat mechanism 44B shown in FIG. 2 is attached to the lumbar support portion 42. However, the present invention is not limited to this, and the advance / retreat mechanism 44B is a fixed part such as the seat back frame 16F. It may be attached to. In this configuration, the inner cable of the push-pull wire 60 in the advance / retreat mechanism 44B is used when the lumbar support portion 42 is displaced in the vertical direction of the seat back without displacing the protruding top portion 42X of the lumbar support portion 42 in the seat back longitudinal direction. The inner cable 60A is moved up and down in the seat back so that 60A is synchronized with the displacement of the lumbar support portion 42.

  On the other hand, in this modified example, when the lumbar support portion 42 is displaced in the seat back vertical direction while the protruding top portion 42X of the lumbar support portion 42 is displaced in the seat back front-rear direction, the displacement of the lumbar support portion 42 and the inner cable A difference is made in the movement amount of 60A. As an example, when the protrusion top portion 42X of the lumbar support portion 42 is displaced forward of the seat back while the lumbar support portion 42 is displaced downward in the seat back, the amount of movement of the inner cable 60A rather than the displacement of the lumbar support portion 42. Increase As a result, the distance between the upper end portion 42A and the lower end portion 42C of the lumbar support portion 42 is reduced, so that the curvature of the curved portion 42B increases and the protruding top portion 42X moves to the front side of the seat back.

  In the above embodiment, when the rear collision prediction unit 36B shown in FIG. 1 predicts a rear collision of the vehicle, the lumbar support devices 40, 72, and 92 are controlled to operate after the pretensioner 34 is operated. However, as a modification, when the rear collision of the vehicle is predicted by the rear collision prediction unit (36B), the pretensioner (34) is operated simultaneously with or after the operation of the lumbar support device (40, 72, 92). Thus, the operation control unit (36A, 88A, 104A) may control the pretensioner (34). As another modification, a configuration in which the pretensioner (34) is not set to operate when a rear collision of the vehicle is predicted by the rear collision prediction unit (36B) may be employed.

  As a modification of the first embodiment, the operation control unit 36A shown in FIG. 1 is configured such that the rear collision prediction unit 36B causes a rear collision of the vehicle when the protruding top 42X of the lumbar support unit 42 is not at the lower limit position. When it is predicted and when the protruding top portion 42X is not arranged at the forward movement position, the protruding top portion 42X moves toward the forward movement position on the front side of the seat back while the lumbar support portion 42 moves toward the movement limit on the lower side of the seat back. The motor body 46M of the lifting mechanism 44A and the motor body 56M of the advance / retreat mechanism 44B shown in FIG. 2 may be controlled so as to move. Further, as another modification of the first embodiment, the operation control unit 36A shown in FIG. 1 is configured such that the rear collision prediction unit 36B causes the rear collision of the vehicle when the protruding top 42X of the lumbar support unit 42 is not at the lower limit position. 2 is controlled, and when the projecting top portion 42X is not disposed at the forward movement position, the motor main body portion 56M of the advance / retreat mechanism 44B shown in FIG. After that, the motor main body 46M of the elevating mechanism 44A may be controlled so that the lumbar support portion 42 moves to the movement limit on the lower side of the seat back.

  Moreover, in the said embodiment, although the buckle apparatus 30 shown by FIG. 1 etc. is standingly arranged in the side part inside the vehicle width direction of the seat cushion 14, you may stand up the buckle apparatus 30 from a vehicle body floor. Further, in addition to the configuration of the above-described embodiment, a moving mechanism that moves the buckle device 30 in the up and down direction (reversibly) is provided, and the lumbar support unit when a rear collision of the vehicle is predicted by the rear collision prediction unit 36B. The position of the buckle device 30 may be lowered downward by operating the moving mechanism simultaneously with or after the operation of 42, 74, 94.

  Similarly, in addition to the configuration of the above-described embodiment, another movement mechanism that moves the anchor plate 24 in the vertical direction (reversibly) is provided between the side portion of the seat cushion 14 on the outer side in the vehicle width direction and the anchor plate 24. When the rear collision prediction unit 36B predicts a rear collision of the vehicle, the other moving mechanism is operated simultaneously with or after the operation of the lumbar support units 42, 74, 94, and the position of the anchor plate 24 is May be lowered downward.

  In addition, regarding “the foremost end portion disposed at the most front side of the seat back” described in claim 1, the portion corresponding to the foremost end portion of the lumbar support portion 42 is constant as in the first embodiment. In some cases, as in the second and third embodiments, the portion corresponding to the foremost end portion of the lumbar support portions 74 and 94 may change.

  Further, “the foremost end portion is displaceable between the forward movement position and the backward movement position” described in claim 1 means that the “forward movement position” is the front limit position in the front-rear direction of the seat back as in the above embodiment. This means that the position of the foremost end portion can be changed using the “retracted position” as the limit position on the rear side in the seat back front-rear direction.

  In addition, the said embodiment and the above-mentioned some modification can be implemented combining suitably.

  Although an example of the present invention has been described above, the present invention is not limited to the above, and it is needless to say that various modifications can be made without departing from the spirit of the present invention. .

DESCRIPTION OF SYMBOLS 10 Crew protection device 12 Vehicle seat 14 Seat cushion 16 Seat back 20 Three-point seat belt device 22X Lap webbing 22Y Shoulder webbing 34 Pretensioner 36A Operation control unit 36B Rear impact prediction unit 42 Lumber support unit 42X Projection top (front end part) )
44 Displacement mechanism 44A Lifting mechanism 44B Advance / Retreat mechanism 70 Occupant protection device 74 Lumber support part 74X Front end part 74Y Front end part 80 Displacement mechanism 88A Operation control part 90 Passenger protection device 94 Lumber support part 94X Front end part 94Y Front end part 100 Displacement Mechanism 104A Operation control part A Seat back vertical direction B Seat back longitudinal direction

Claims (4)

Provided on the seat back of the vehicle seat, and supports the waist of the occupant seated on the seat cushion of the vehicle seat, and the foremost end portion disposed on the front side of the seat back supports the upper side of the waist A position where the position is an upper limit position in the seat back vertical direction and a position that supports the lower side of the waist is a lower limit position in the seat back vertical direction, and a forward position that is displaceable at least between the upper limit position and the lower limit position and presses the waist A lumbar support portion that is displaceable between a retracted position on the rear side of the seat back with respect to the advanced position;
A displacement mechanism for displacing the foremost end portion of the lumbar support portion;
A rear collision prediction unit for predicting a rear collision of the vehicle;
When a rear-end collision of the vehicle is predicted by the rear impact prediction unit in a state where the front end portion of the lumbar support portion is not at the lower limit position, the front end portion is set at the lower limit position and the forward position. An operation control unit for controlling the displacement mechanism,
An occupant protection device. The lumbar support part is movable in the seat back vertical direction,
The range of movement of the lumbar support portion in the vertical direction of the seat back when the rear collision prediction of the vehicle is predicted by the rear collision prediction unit is lower than the range of movement of the lumbar support portion in the vertical direction of the seat back. The occupant protection device according to claim 1, wherein the occupant protection device is extended sideways. A three-point seat belt device for restraining the upper body of the occupant seated on the seat cushion with shoulder webbing and restraining the waist of the occupant with lap webbing;
A pretensioner that operates when a rear collision of the vehicle is predicted by the rear collision prediction unit and applies tension to the shoulder webbing;
Have
The operation control unit is configured so that the rear end collision of the lumbar support unit is not in the lower limit position and the rear collision prediction unit predicts a rear collision of the vehicle, and then the front end is operated after the pretensioner is operated. The occupant protection device according to claim 1 or 2, wherein the displacement mechanism is controlled so that a part is set at the lower limit position and at the advance position. The displacement mechanism includes an elevating mechanism for moving the lumbar support portion in a seat back up-down direction, and an advancing / retreating mechanism for moving the foremost end portion in a seat back front-back direction,
When the rear collision prediction unit predicts a rear collision of the vehicle in a state where the front end portion of the lumbar support portion is not at the lower limit position, the operation control unit arranges the front end portion at the forward position. If not, the forward / backward mechanism is moved so that the foremost end portion moves to the forward position on the front side of the seat back after the elevating mechanism is controlled so that the lumbar support part moves to the movement limit on the lower side of the seat back. 4. The control device according to claim 1, wherein the elevating mechanism is controlled so that the lumbar support portion moves to a movement limit on a lower side of a seat back when the foremost end portion is arranged at the forward movement position. The occupant protection device according to claim 1.

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