JP4182024B2 - Active knee bolster - Google Patents

Description

  The present invention relates to an active knee bolster, and more particularly to an active knee bolster mounted on a vehicle such as an automobile.

Conventionally, in an active knee bolster mounted on a vehicle such as an automobile, the lower part of the front end of the knee protection device for restraining the occupant's lower limb is rotatably attached to the body side member, and the knee protection device is rotated using a rack and a pinion. By doing so, a configuration is known in which the leg space is widened when getting on and off the vehicle body (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 63-81758

  However, in the active knee bolster in the configuration of Patent Document 1, it is necessary to dispose a rack, a pinion, and a drive motor on the vehicle body front side of the knee protection device. As a result, the apparatus becomes large. For this reason, a large arrangement space along the longitudinal direction of the vehicle body is required, and the vehicle body mounting performance is deteriorated.

  An object of the present invention is to obtain an active knee bolster that can be reduced in size and can return the knee protection device from the restrained position to the retracted position in consideration of the above facts.

Active knee bolster of the present invention according to claim 1, the inner cylinder knee protector is supported on the rear end,
With movably supporting said inner cylinder disposed within an outer tube which is fixed to the vehicle body via the bracket,
Is fixed to the front end of the outer cylinder, which is incorporated in disposed the motor case into said inner cylinder, a motor for moving the inner cylinder between a retracted position and an arresting position,
A sun gear, a ring gear, and a pinion that are disposed in the inner cylinder and are movably connected to a driving shaft of the motor in the front-rear direction are provided, and the inner cylinder is moved between a restraining position and a storage position. Planetary gear for
A cap fastened to a screw portion formed on the outer peripheral portion of the front end portion of the outer cylinder, and sandwiching the motor case with the front end portion of the outer cylinder;
Have
When the inner cylinder receives a load of a predetermined value or more from the rear of the vehicle body toward the front of the vehicle body, the load is applied to the inner cylinder, the ring gear, the motor case, the cap, the outer cylinder, and the bracket. Via the vehicle body .

Accordingly, the actuator of the active knee bolster, the inner cylinder knee protector is supported on the rear end portion is fixed to the vehicle body, the outer cylinder for movably supporting the inner cylinder disposed inside the inner cylinder disposed, are fixed to the front end of the outer cylinder, a motor for moving the inner cylinder between a retracted position and an arresting position, is disposed within the inner cylinder, it is coupled to a motor , a planetary gear for moving the inner cylinder between a retracted position and an arresting position, in that a configuration, it houses the motor and the planetary gear in the interior of the outer cylinder and the inner cylinder. For this reason, the apparatus can be miniaturized. Further, through the planetary gear by the motor, together with the inner cylinder can move the knee protection device is supported on the end after the inner cylinder by moving relative to the outer tube from the storage position to the arresting position, the knee protector The restraint position can be returned to the storage position. In addition, when the active knee bolster's lower limb restraint part comes into contact with the occupant's lower limb and the inner cylinder receives a load of a predetermined value or more from the rear of the vehicle body toward the front of the vehicle body, the sun gear moves in the front-rear direction on the motor drive shaft. Therefore, the load is transmitted to the vehicle body via the inner cylinder, ring gear, motor case, cap, outer cylinder, and bracket. As a result, a large load does not act on the drive shaft of the motor, and damage to the motor can be prevented. For this reason, after that, a leg restraint part can be returned from a restraint position to a storing position by operating a motor.

Active knee bolster of the present invention according to claim 1, the inner cylinder knee protector is supported on the rear end, while movably supporting the inner cylinder disposed therein, to the vehicle body via the bracket a fixed outer cylinder, fixed to the front end of the outer tube, which is incorporated in disposed the motor case into the inner cylinder, a motor for moving the inner cylinder between a retracted position and an arresting position And a sun gear, a ring gear, and a pinion that are disposed in the inner cylinder and are movably connected to the drive shaft of the motor in the front-rear direction, to move the inner cylinder between the restraining position and the storage position. A planetary gear and a cap fastened to a screw portion formed on the outer peripheral portion of the front end portion of the outer cylinder, and a motor case sandwiched between the front end portion of the outer cylinder and the inner cylinder from the rear of the vehicle body If a load greater than the specified value is applied toward the front of the vehicle, the load , The ring gear, the motor case, the cap, the outer cylinder, to be transmitted to the vehicle body via a bracket, with can be miniaturized, the leg restraining portion of the active knee bolster abuts and the lower extremities of the driver, the inner cylinder When a load of a predetermined value or more is applied from the rear of the vehicle body to the front of the vehicle body, the motor can be prevented from being damaged, and the knee protection device can be returned from the restrained position to the retracted position.

  An embodiment of an active knee bolster according to the present invention will be described with reference to FIGS.

  In the figure, the arrow FR indicates the vehicle body front direction, and the arrow UP indicates the vehicle body upward direction.

  As shown in FIG. 6, the present embodiment includes an acceleration sensor 12 as a collision detection unit that detects deceleration of the vehicle body 10 and detects a collision of the vehicle body 10. Further, the acceleration sensor 12 is disposed on each of the left and right front side members, and the acceleration sensor 12 is connected to a control circuit 14 serving as control means having a microcomputer.

  In the instrument panel 18 of the vehicle body 10, active knee bolsters (lower limb restraining means) 24 are respectively disposed in front of the left and right front seats 20 that are a driver seat and a passenger seat. The left and right lower limbs (especially knees) 28A of the occupant 28 seated on the front seat 20 are arranged in pairs on the left and right sides.

  The pair of left and right active knee bolsters 24 includes a lower limb restraining portion 30 as a knee protection device that restrains the left and right lower limbs 28A of the occupant 28 seated on the front seat 20 from the front of the vehicle body, and the lower limb restraining portion 30 of the occupant 28. It comprises an actuator 32 for moving to the lower limb restraining position on the lower limb 28A side.

  As shown in FIG. 5, the lower limb restricting portion 30 of the active knee bolster 24 abuts on the lower limb (particularly the knee) 28 </ b> A of the occupant 28 at the restraint position on the rear side of the vehicle body (the position of the two-dot chain line in FIG. 6). At the same time, a part of the general surface 18A of the instrument panel 18 is configured at the storage position (the position indicated by the solid line in FIGS. 5 and 6).

  As shown in FIG. 1, a reinforcement bracket 34 is fixed to the instrument panel reinforcement 33 of the vehicle body, and an attachment portion 34 </ b> A of the reinforcement bracket 34 is an inclined portion that extends from the vehicle body front upper side to the vehicle body rear lower side. ing. A plurality of stud bolts 36 are disposed on the attachment portion 34 </ b> A of the reinforcement bracket 34, and these stud bolts 36 pass through the attachment holes 40 of the leg bracket 38 fixed to the actuator 32. . A nut 42 is fastened to the stud bolt 36, and the leg bracket 38 is fixed to the reinforcement bracket 34 by the stud bolt 36 and the nut 42.

  The actuator 32 has a double pipe structure including an outer cylinder 46 and an inner cylinder 48, and a leg bracket 38 is fixed to the outer peripheral portion of the outer cylinder 46. In addition, a lower leg restraining portion 30 is fixed to a rear end portion 48A, which is one end portion of the inner cylinder 48, by a bracket (not shown), and an inner end of a front end portion 48B, which is the other end portion of the inner cylinder 48, is secured. A plurality of stoppers 52 are disposed on the peripheral portion at predetermined intervals in the circumferential direction. These stoppers 52 are slidably inserted in grooves 53 formed along the front-rear direction on the outer peripheral portion of the motor case 60, and prevent the inner cylinder 48 from rotating. A screw portion 48C is formed on the inner peripheral portion of the inner cylinder 48 on the front end portion 48B side.

  A rear end portion 46 </ b> A that is one end portion of the outer cylinder 46 is opened, and a pipe-shaped slider 54 is disposed between the outer cylinder 46 and the inner cylinder 48. The slider 54 is made of a resin material or the like so that friction with the inner cylinder 48 is reduced, and is fixed to an attachment hole 56 formed in the outer cylinder 46 by a claw 54A formed on the outer peripheral portion.

  Accordingly, the outer cylinder 46 supports the inner cylinder 48 disposed inside via the slider 54 so as to be movable in the longitudinal direction of the vehicle body (the direction of arrow A and arrow B in FIG. 1). Further, a screw portion 46C is formed on the outer peripheral portion of the front end portion 46B, which is the other end portion of the outer cylinder 46, and a cap 58 disposed on the front end portion 46B of the outer cylinder 46 is formed on the screw portion 46C. It is concluded.

A flange 60A formed at the front end of a motor case 60 in which a motor 59 is built is sandwiched between the front end 46B of the outer cylinder 46 and the cap 58. The motor case 60 is connected to the front end of the outer cylinder 46. It is fixed to the part 46B. Therefore, the motor 59 is disposed inside the inner cylinder 48.

  The motor 59 is electrically connected to the control circuit 14, and the wiring 61 of the motor 59 is inserted through an opening 63 formed in the center of the bottom 58 </ b> A of the cap 58.

  As shown in FIG. 3, the flange 60A of the motor case 60 has a plurality of non-rotating cutouts 62 formed at predetermined intervals along the circumferential direction, and these cutouts 62 are formed at the bottom 58A of the cap 58. It is engaged with the convex part 64 formed in the outer peripheral part.

As shown in FIG. 1 , a planetary gear 70 is disposed on the drive shaft 59 </ b> A protruding from the rear end portion of the motor case 60, and the rotational force of the motor 59 is transmitted through the planetary gear 70 to the inner cylinder 48. The screw portion 48C is transmitted.

  As shown in FIG. 4, the planetary gear 70 is a well-known simple planetary structure including a sun gear 72 disposed on the drive shaft 59 </ b> A of the motor 59, a ring gear 74, and two pinions 76. For example, when the sun gear 72 disposed on the drive shaft 59A of the motor 59 rotates in the clockwise direction of FIG. 4 (the direction of the arrow C in FIG. 4), the two pinions 76 become counterclockwise in FIG. 4 in the direction of arrow D), and the ring gear 74 is rotated in the clockwise direction of FIG. 4 (direction of arrow E in FIG. 4).

  As shown in FIG. 3, a screw portion 74 </ b> A is formed on the outer peripheral portion of the ring gear 74, and a cover 80 is disposed on the rear end portion 74 </ b> B of the ring gear 74. The cover 80 is attached to the motor case 60 with bolts 82. The cross-sectional shape of the drive shaft 59A of the motor 59 is cut into a D shape or the like, and the sun gear 72 is movable in the front-rear direction along the drive shaft 59A.

  As shown in FIG. 1, a screw portion 74A formed on the outer peripheral portion of the ring gear 74 is screwed with the screw portion 48C of the inner cylinder 48, and the planetary gear 70 is rotated by the rotation of the drive shaft 59A of the motor 59. The inner cylinder 48 moves in the longitudinal direction of the vehicle body (in the direction of arrow A and arrow B in FIG. 1).

  As shown in FIG. 2, when the inner cylinder 48 moves rearward (in the direction of arrow A in FIG. 2) and starts moving from the storage position shown in FIG. 1 to the restraint position shown in FIG. While the motor 59 stops, the stopper 52 fixed to the inner peripheral portion of the front end portion 48B of the inner cylinder 48 comes into contact with the front end portion 74C of the ring gear 74, so that the inner cylinder 48 stops at the restraining position. ing.

Further, the lower limb restraining portion 30 of the active knee bolster 24 contacts the lower limb (especially knee) 28A of the occupant 28, and the inner cylinder 48 is a predetermined value or more from the rear of the vehicle body toward the front of the vehicle body (in the direction of arrow B in FIG. 2). Since the sun gear 72 can move in the front-rear direction along the drive shaft 59A of the motor 59, the load (arrow F in FIG. 2) is the inner cylinder 48, the ring gear 74, The motor case 60, the cap 58, the outer cylinder 46, and the leg bracket 38 can be transmitted in this order. As a result, a large load does not act on the drive shaft 59A of the motor 59, and the motor 59 is not damaged.

  Therefore, by rotating the motor 59 in the reverse direction with respect to the rotation direction when the lower limb restraining portion 30 of the active knee bolster 24 is moved from the retracted position to the restraining position, the lower limb restraining portion 30 together with the inner cylinder 48 is shown in FIG. 1 can be returned to the storage position shown in FIG.

  In the present embodiment, as shown in FIG. 6, the airbag device for the passenger seat and the driver seat are disposed on the upper portion 18 </ b> B of the instrument panel 18 and the steering wheel 90. The airbag bag body 92 (only the airbag for the driver's seat is shown in FIG. 6) is inflated and deployed toward the upper body 28B of the occupant 28 seated on the front seat 20. Reference numeral 94 in FIG. 6 indicates a seat belt.

  Next, the operation of this embodiment will be described.

  In this embodiment, the actuator 32 of the active knee bolster 24 is fixed to the inner cylinder 48 in which the lower limb restraining portion 30 is supported by the rear end portion 48A and the instrument panel reinforcement 33 of the vehicle body, and the inner cylinder is disposed inside. An outer cylinder 46 that movably supports 48, and is disposed in the inner cylinder 48 and fixed to the front end portion 46B of the outer cylinder 46, so as to move the inner cylinder 48 between a restraining position and a storage position. And a planetary gear 70 disposed in the inner cylinder 48 and connected to the motor 59 for moving the inner cylinder 48 between the restraining position and the storage position. Since the motor 59 and the planetary gear 70 can be accommodated in the outer cylinder 46 and the inner cylinder 48, the actuator 32 can be reduced in size.

  Further, when the vehicle body 10 collides, the control circuit 14 first determines whether or not the vehicle body 10 has collided based on input signals from the acceleration sensors 12 respectively disposed on the left and right front side members. .

  When it is determined that the vehicle body 10 has collided, the control circuit 14 operates the motor 59 of the active knee bolster 24 and rotates the drive shaft 59A of the motor 59 in the normal direction. As a result, the forward movement of the drive shaft 59A of the motor 59 starts the linear movement of the inner cylinder 48 to the rear of the vehicle body (in the direction of arrow A in FIG. 1) via the planetary gear 70.

  After that, the motor 59 stops after a predetermined time, and as shown in FIG. 2, the stopper 52 fixed to the inner peripheral portion of the front end portion 48B of the inner cylinder 48 comes into contact with the front end portion 74C of the ring gear 74, The inner cylinder 48 stops at the restraining position.

  As a result, the lower limb restraining portions 30 fixed to the rear end portions 48A of the left and right inner cylinders 48 linearly move in the occupant direction (in the direction of arrow A in FIG. 2), and as shown by the two-dot chain line in FIG. The left and right lower limbs 28A of the occupant 28 seated on the seat 20 abut from the front of the vehicle body. Therefore, the left and right lower limbs 28 </ b> A of the occupant 28 can be restrained from the front of the vehicle body by the left and right lower limb restraining portions 30.

On the other hand, when the left and right lower limb restraining portions 30 are pressed by the left and right lower limbs 28A of the occupant 28, the inner cylinder 48 moves from the lower limbs 28A toward the front of the vehicle body (in the direction of arrow B in FIG. 2) via the lower limb restraining portions 30. When the load exceeds a predetermined value, the sun gear 72 can move in the front-rear direction along the drive shaft 59A of the motor 59, so the load (arrow F in FIG. The ring gear 74, the motor case 60, the cap 58, the outer cylinder 46, and the leg bracket 38 are transmitted in this order. As a result, a large load does not act on the drive shaft 59A of the motor 59, and the motor 59 is not damaged.

  Therefore, by rotating the motor 59 in the reverse direction, the lower leg restraining portion 30 together with the inner cylinder 48 can be moved forward (in the direction of arrow B in FIG. 2) to return from the restraining position shown in FIG. 2 to the retracted position shown in FIG. . As a result, it is possible to widen the leg space when getting on and off the vehicle body.

  Therefore, in this embodiment, the actuator 32 of the active knee bolster 24 can be downsized, and the lower leg restraining portion 30 of the active knee bolster 24 can be returned from the restrained position to the retracted position.

  In the above, the present invention has been described in detail with respect to specific embodiments. However, the present invention is not limited to the above embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art. For example, in the above embodiment, the acceleration sensor 12 is used to determine the collision, but instead of this, the collision of the vehicle body before the collision can be achieved by using a camera, a redder, etc., denoted by reference numeral 98 in FIG. It is good also as a structure which senses, ie, performs collision prediction and operates an active knee bolster.

  In the above embodiment, the active knee bolster of the present invention is applied to the front seats (driver's seat and front passenger seat). However, the active knee bolster of the present invention can also be applied to a seat other than the front seat such as a rear seat.

It is a sectional side view which shows the storing position of the active knee bolster which concerns on one Embodiment of this invention. It is a sectional side view which shows the restraint position of the active knee bolster which concerns on one Embodiment of this invention. It is the disassembled perspective view seen from the vehicle body diagonally rear which shows a part of actuator of the active knee bolster which concerns on one Embodiment of this invention. It is the front view seen from the vehicle body rear which shows the planetary gear of the actuator of the active knee bolster which concerns on one Embodiment of this invention. It is a schematic plan view which shows the active knee bolster which concerns on one Embodiment of this invention. It is a schematic sectional side view which shows the compartment front part to which the active knee bolster which concerns on one Embodiment of this invention was applied.

Explanation of symbols

24 Active knee bolster 30 Lower limb restraint part (knee protector)
32 Actuator 46 Outer cylinder 46A Outer cylinder rear end 46B Outer cylinder front end 46C Outer cylinder screw part 48 Inner cylinder 48A Inner cylinder rear end 48B Inner cylinder front end 52 Stopper 54 Slider 58 Cap 59 Motor 60 Motor Case 70 Planetary gear 72 Sun gear 74 Ring gear 74A Ring gear screw portion 74B Ring gear rear end portion 74C Ring gear front end portion 76 Pinion 80 Cover

Claims (1)

A cylindrical inner knee protector is supported on the rear end,
An outer cylinder fixed to the vehicle body via a bracket, and movably supporting the inner cylinder disposed inside;
Is fixed to the front end of the outer cylinder, which is incorporated in disposed the motor case into said inner cylinder, a motor for moving the inner cylinder between a retracted position and an arresting position,
A sun gear, a ring gear, and a pinion that are disposed in the inner cylinder and are movably connected to a driving shaft of the motor in the front-rear direction are provided, and the inner cylinder is moved between a restraining position and a storage position. Planetary gear for
A cap fastened to a screw portion formed on the outer peripheral portion of the front end portion of the outer cylinder, and sandwiching the motor case with the front end portion of the outer cylinder;
Have
When the inner cylinder receives a load of a predetermined value or more from the rear of the vehicle body toward the front of the vehicle body, the load is applied to the inner cylinder, the ring gear, the motor case, the cap, the outer cylinder, and the bracket. Active knee bolster characterized by being transmitted to the vehicle body via

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