JP2007137290A - Impact absorbing steering column device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively reduce inertia force (input from occupant in secondary collision) working on an occupant in vehicle collision in good timing. <P>SOLUTION: A column side member 41 to hold a steering wheel is connected to and supported on a car body side member 31 assembled on a part of a car body through a connecting mechanism at a set position, and it moves toward the front of a vehicle from the set position as connecting support by the connecting mechanism is released when it receives a load of more than a specified value toward the front of the vehicle from the occupant in the vehicle collision. Thereafter, an impact energy absorbing device B functions and a specified energy absorbing load is provided when the column side member 41 moves to the front of the vehicle against the car body side member 31. Furthermore, the impact energy absorbing device B is furnished with an actuator 51 and a shaft 52 to work in timing to change from acceleration to deceleration after ground speed of the column side member 41 changes from deceleration to acceleration by input of from the occupant in the vehicle collision and increases (adds) the energy absorbing load in the same timing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an impact absorbing steering column apparatus including a collision energy absorbing device that absorbs a secondary collision energy (hereinafter simply referred to as collision energy) of a passenger (driver) at the time of a vehicle collision.

As one of this type of shock absorbing steering column device, the column side member assembled to the steering column side that rotatably holds the steering wheel is set to the vehicle body side member assembled to a part of the vehicle body. When the vehicle is connected and supported via a connecting mechanism at a position and receives a load of a predetermined value or more from the occupant toward the front of the vehicle at the time of a vehicle collision, the connecting support by the connecting mechanism is released and the vehicle is moved forward from the set position. In some cases, the collision energy absorbing device functions as a result of the forward movement of the vehicle, and a predetermined energy absorbing load is obtained (for example, Patent Documents). 1).
JP 2003-267229 A

  In the shock absorption type steering column device described in Patent Document 1 described above, an occupant load loss point is detected at the time of a vehicle collision, and an energy absorption load (collapse load) in the collision energy absorbing device is detected from the occupant load loss point. In the direction where the passenger leaves the steering wheel due to the reaction after the load is applied to the steering wheel by the input from the passenger (occupant's inertial force) at the time of collision. This is regarded as the point of time when the load is lost after moving.

  However, the input from the occupant (occupant's inertial force) at the time of the vehicle collision varies depending on the occupant's physique (weight), the degree of collision, etc., and depending on the input from the occupant (occupant's inertial force) at the time of the collision After the load is applied to the steering wheel, the reaction may not move in the direction in which the occupant leaves the steering wheel, and the energy absorption load (collapse load) may not be increased accurately.

  In the present invention, in the event of a vehicle collision, when the input from the occupant acts on the column side member and the column side member moves from the set position toward the front of the vehicle, the ground speed of the column side member is The column side member that is attached to the steering column side that holds the steering wheel rotatably is attached to a part of the vehicle body. The vehicle body side member is connected and supported via a connection mechanism at a set position, and when a load of a predetermined value or more is applied from the occupant toward the front of the vehicle at the time of a vehicle collision, the connection support by the connection mechanism is performed. It is set so that it is released and moves from the set position toward the front of the vehicle. In the shock absorption type steering column device set so as to obtain an energy absorption load, when the ground speed of the column side member changes from deceleration to acceleration due to an input from the occupant at the time of a vehicle collision, the timing when the acceleration changes from deceleration to acceleration The load adding means for starting the operation and applying an energy absorption load to the column side member is provided.

  In this shock absorption type steering column device, the load adding means starts operating at the timing when the ground speed of the column side member changes from deceleration to acceleration and then changes from acceleration to deceleration due to input from the occupant during a vehicle collision. An energy absorption load is added to the column side member. Therefore, after the load adding means starts operation, the energy absorption load in the device can be increased, the total amount of collision energy can be increased, and the impact acting on the occupant can be accurately reduced. Is possible.

  By the way, the phenomenon in which the ground speed of the column side member changes from deceleration to acceleration after a vehicle collision, and then changes from acceleration to deceleration occurs when the input from the passenger acts on the column side member and the column side member moves forward from the set position to the vehicle front. When moving toward, it occurs in any case, and the timing at which the ground speed of the column side member changes from acceleration to deceleration due to the phenomenon described above is the timing at which, for example, the chest deceleration of the occupant begins to drop from the peak. is there. For this reason, an energy absorption load can be applied to the column side member by the load adding means at this timing, and the inertial force acting on the occupant is timed before the column side member reaches the forward movement end (stroke end). It is possible to effectively reduce the peak value of the occupant's chest deceleration that occurs thereafter (the peak value when the column-side member reaches the front moving end and bottoms out) is effectively reduced. It is possible.

  In carrying out the present invention, the load adding means includes a collision detection sensor for detecting a collision of the vehicle, a speed detection sensor for detecting the ground speed of the column side member, and a vehicle based on signals from these sensors. By starting the operation at a timing when the ground speed of the column side member changes from deceleration to acceleration and then from acceleration to deceleration at the time of a collision, the energy absorption load obtained by the collision energy absorbing device is increased by a predetermined amount. It is also possible to be an electric load adding means provided with an electric load increasing device for applying an energy absorbing load to the column side member. In this case, it is possible to add the energy absorption load to the column side member with high accuracy and with good timing by the load adding means.

  In carrying out the present invention, the load applying means includes a steel ball that moves in the front-rear direction in accordance with a change in ground speed of the column-side member, and a spring that controls the movement of the steel ball. The column side member is engaged with the steel ball at a timing when the ground speed of the column side member changes from deceleration to acceleration and then changes from acceleration to deceleration at the time of a vehicle collision. It is also possible to be a mechanical load adding means provided with an energy absorbing member for adding an energy absorbing load to the side member. In this case, the electric load increasing device and the sensor and control means for controlling the operation of the electric load increasing device are not required, and the load adding means can be configured simply and inexpensively.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 show a first embodiment of the shock absorbing steering column apparatus according to the present invention. In the shock absorbing steering column apparatus of the first embodiment, as shown in FIGS. The steering shaft 10 includes an upper shaft 11 and a lower shaft 12 that can extend and contract in the axial direction and transmit torque, and a steering column 20 that supports the steering shaft 10 rotatably and can expand and contract in the axial direction. The outer tube 21 and the inner tube 22 are provided.

  The upper shaft 11 is supported by an outer tube 21 via a bearing (not shown) so as to be rotatable and immovable in the axial direction, and a steering wheel 13 to which an airbag device A is mounted at the upper end of the right end in FIG. Are assembled so that they can rotate together. On the other hand, the lower shaft 12 is rotatably supported on the inner tube 22 via a bearing (not shown), and is an intermediate shaft capable of expanding and contracting and transmitting torque via the universal joint 14 at the lower end portion at the left end of FIG. The intermediate shaft 15 is connected to a steering gear box 17 via a universal joint 16.

  2 and 3, the outer tube 21 is fitted and connected to the upper end portion of the inner tube 22 at the lower end portion so as to be slidable in the axial direction, and is attached to a bracket 21a fixed to the lower surface of the lower end portion. Thus, a vehicle body side bracket (also referred to as a steering support bracket) that is fixed to a part of the vehicle body (not shown) via an upper support mechanism US that can be tilted and telescopically adjusted and a pair of left and right connecting mechanisms CS (see FIG. 4). ) 31. On the other hand, as shown in FIG. 2, the inner tube 22 is assembled to the vehicle body side bracket 32 via a lower support mechanism LS that can be rotated by a bracket 22 a fixed to the upper surface of the lower end portion.

  The upper support mechanism US includes a breakaway bracket 41 that supports the bracket 21a fixed to the outer tube 21 so as to be tiltable (tiltable) in the vertical direction, and the bracket fixed to the outer tube 21 with respect to the breakaway bracket 41. A tilt mechanism capable of fixing / releasing 21a and a telescopic mechanism capable of fixing / releasing the outer tube 21 with respect to the inner tube 22 are provided.

  The tilt mechanism is known per se and can be fixed / released by operating the handle. In the released state, the steering shaft 10 and the steering column 20 can be tilted up and down integrally with the breakaway bracket 41. To do. The telescopic mechanism is known per se and can be fixed and released by a handle operation. In the released state, the upper shaft 11 and the outer tube 21 are telescopically adjusted in the column axial direction with respect to the lower shaft 12 and the inner tube 22. Make it possible.

  Each connecting mechanism CS supports the breakaway bracket 41 with respect to the vehicle body side bracket 31 at the set position shown in FIG. 2, and includes a resin capsule 42 and a metal collar 43, which will be described later, a bolt 44, A nut 45 is provided, and when a load of a predetermined value or more is received from the occupant toward the front of the vehicle in the event of a vehicle collision, the connection of the breakaway bracket 41 to the vehicle body side bracket 31 is released, and the breakaway bracket 41 is set. It is comprised so that it may move toward a vehicle front from a position.

  The breakaway bracket 41 has a pair of arms 41a and 41b extending left and right. As shown in FIG. 4, the resin capsules are provided in the slit holes 41a1 and 41b1 provided in the arms 41a and 41b. 42 and the metal collars 43, and are assembled to the vehicle body side bracket 31 using the bolts 44. Each bolt 44 is screwed and fixed to each nut 45 fixed to the vehicle body side bracket 31 in advance.

  Each of the slit holes 41a1 and 41b1 of the breakaway bracket 41 is used to push the steering wheel 13 or the like forward from the set position shown in FIG. 3), the breakaway bracket 41 can be moved forward and backward. As shown by the broken lines in FIG. 3, the arms 41a and 41b extend from substantially the center to the rear end and extend to the rear end. Open. Each resin capsule 42 has a cylindrical portion 42a that fits into each slit hole 41a1, 41b1, and is fixedly attached to the upper surface of each arm 41a, 41b, and is sheared with a predetermined load during a secondary collision. It has come to be. Each metal collar 43 is press-fitted into the cylindrical portion 42 a of each resin capsule 42, and in a state where the metal collar 43 is assembled to the vehicle body side bracket 31 using each bolt 44, each resin capsule 42 is held in a secondary collision. Shearable.

  The lower support mechanism LS supports the inner tube 22 in the steering column 20 so that the inner tube 22 can always be tilted (rotated), and is rotatably fitted in a mounting hole 22a1 formed in a bracket 22a fixed to the lower end portion of the inner tube 22. A collar (not shown) to be combined, a bolt and a nut (not shown), and the like for fixing the collar to a part of the vehicle body (not shown).

  In the first embodiment, the collision energy absorbing device B is interposed between the vehicle body side bracket 31 and the breakaway bracket 41. The collision energy absorbing device B includes a collision detection sensor S1 (see FIG. 1) that detects a vehicle collision, a ground speed sensor S2 (see FIG. 1) that detects a ground speed of the vehicle body, a breakaway bracket 41, and an outer tube 21. And a relative movement speed sensor S3 (see FIG. 1) for detecting the relative speed of the column side member such as the steering wheel 13 with respect to the vehicle body, and the operation is controlled by the electric control unit ECU based on signals from these sensors S1 to S3. Actuator 51, a shaft 52 driven in the left-right direction by the actuator 51, an energy absorbing member 53 whose middle portion is curved and deformed by the shaft 52, and an energy absorbing member 53 at the front and rear of the shaft 52. A holder 54 for holding is provided.

  The collision energy absorbing device B can change the energy absorbing load at the time of the secondary collision from a predetermined small energy absorbing load to a large energy absorbing load by a predetermined amount, and the change timing is the breakaway bracket 41 or the like at the time of the secondary collision. The ground speed of the column side member (see the one-dot chain line in FIG. 6) is set to the timing t1 (see FIG. 6) at which the acceleration changes from the deceleration to the acceleration after the deceleration to acceleration. This change timing is determined by the electric control unit ECU based on the ground speed of the column side member such as the breakaway bracket 41 calculated based on the signals of the ground speed sensor S2 and the relative movement speed sensor S3. It is configured.

  The actuator 51 is an electromagnetic solenoid whose operation (energization) is controlled by the electric control unit ECU, and is fixed on the breakaway bracket 41 as shown in FIGS. The actuator 51 is configured to drive the shaft 52 to the left by a predetermined amount from the fixed position shown in FIG. 4 when operating, and the shaft 52 constitutes an electric load increasing device.

  As shown in FIG. 4, the shaft 52 has a small-diameter portion 52a, a tapered portion 52b, and a large-diameter portion 52c. The shaft 52 is assembled to a support 55 fixed on the breakaway bracket 41 so as to be movable left and right. As shown in FIGS. 2 and 4, the upper outer periphery of the energy absorbing member 53 is slidably engaged with the lower surface of the intermediate portion.

  The energy absorption member 53 is deformed between the shaft 52 and each holder 54 to absorb the collision energy when the breakaway bracket 41 moves away from the vehicle body side bracket 31 and moves forward in a secondary collision. The plate is engaged with a locking portion 31a provided on the vehicle body side bracket 31 through an engagement hole 53a1 of a standing portion 53a provided at the rear end, and movement to the front of the vehicle is restricted.

  As shown in FIGS. 2 and 5, each holder 54 includes a pair of left and right columns 54 a integrally provided on the breakaway bracket 41 on both the left and right sides of the energy absorbing member 53. And a pair of upper and lower support shafts 54b that slidably hold the energy absorbing member 53. Each holder 54 has a function of deforming the energy absorbing member 53 by the shaft 52 and also has a guide function for guiding the movement of the breakaway bracket 41 forward of the vehicle.

  The electric control unit ECU controls the operation of the actuator 51 in the inflator (not shown) of the airbag device A and the collision energy absorbing device B at the time of a vehicle collision. The inflator of the airbag device A and the collision energy absorbing device The actuator 51 is electrically connected to the B actuator 51, and is also electrically connected to the collision detection sensor S1, the ground speed sensor S2, and the relative movement speed sensor S3 (see FIG. 1).

  In this electric control unit ECU, a control program for operating the inflator of the airbag device A is executed based on a detection signal from the collision detection sensor S1 at the time of a vehicle collision, and the above-described collision detection sensor S1 and the ground speed A control program for controlling the operation of the actuator 51 in the collision energy absorbing device B is executed based on detection signals from the sensor S2 and the relative movement speed sensor S3.

  Specifically, the control program for controlling the operation of the actuator 51 is the timing t1 when the ground speed of the column side member such as the breakaway bracket 41 is changed from the deceleration to the acceleration after the secondary collision, and the timing t1 (see FIG. 6). 5), the actuator 51 is kept in a non-energized state, and the shaft 52 is held in the state shown in FIG. 5A. After the timing t1, the actuator 51 is kept in an energized state, and the shaft 52 is shown in FIG. It is set to be held in the state.

  In the first embodiment configured as described above, in the event of a vehicle collision, the inflator of the airbag device A, whose operation is controlled by the electric control unit ECU, is activated to prepare for a secondary collision of the driver, During the secondary collision of the driver, the operation of the actuator 51 in the collision energy absorbing device B is controlled by the electric control unit ECU, the deformation amount of the energy absorbing member 53 is controlled, and the secondary collision of the driver is alleviated.

  By the way, at the time of the secondary collision of the driver, the actuator 51 remains until the ground speed of the column side member such as the breakaway bracket 41 changes from deceleration to acceleration until the timing t1 (see FIG. 6) changes from acceleration to deceleration. The shaft 52 is held in the state shown in FIG. 5A because it is in a non-energized state, and the energy absorbing member 53 can be slightly deformed between the small diameter portion 52a of the shaft 52 and each holder 54. Therefore, the energy absorbing member 53 absorbs the collision energy with a small energy absorbing load as the column side member such as the breakaway bracket 41 moves forward of the vehicle.

  Further, after timing t1, the actuator 51 is energized, the shaft 52 is held in the state shown in FIG. 5B, and the energy absorbing member 53 includes the large-diameter portion 52c of the shaft 52 and each holder 54. Since it can be greatly deformed in the meantime, the energy absorbing member 53 absorbs the collision energy with a large energy absorbing load as the column side member such as the breakaway bracket 41 moves forward of the vehicle.

  Therefore, after the shaft 52 is driven by the actuator 51 and the energy absorption load by the energy absorption member 53 is changed from a small energy absorption load to a large energy absorption load, the energy absorption load in the device can be increased by a predetermined amount. Thus, the total amount of collision energy absorbed can be increased, and the impact acting on the occupant can be accurately reduced.

  By the way, the phenomenon in which the ground speed of the column side member such as the breakaway bracket 41 changes from deceleration to acceleration after the vehicle crashes and then changes from acceleration to deceleration occurs when the input from the occupant acts on the steering wheel 13 and the breakaway bracket 41 and the like. When the column side member moves from the set position toward the front of the vehicle, it occurs in any case, and the timing t1 at which the ground speed of the column side member such as the breakaway bracket 41 changes from acceleration to deceleration due to the phenomenon described above. Is the timing when the occupant's chest deceleration, for example, starts to drop from the peak P1, as shown in FIG.

  For this reason, the energy absorption load can be increased (applied) to the column side member such as the breakaway bracket 41 by the actuator 51 and the shaft 52 at this timing t1, and the column side member such as the breakaway bracket 41 is moved forward. It is possible to effectively reduce the inertial force acting on the occupant in a timely manner, and the peak value P2 of the occupant's chest deceleration that occurs thereafter (the column side member reaches the forward movement end, so-called , The peak value when bottoming out) can be effectively reduced. The two-dot chain line of the chest deceleration shown in FIG. 6 is for the case where the actuator 51 and the shaft 52 do not operate at the timing t1 described above.

  In the first embodiment, the load adding means for increasing (applying) a predetermined amount of energy absorption load to the column side member such as the breakaway bracket 41 at the timing t1 described above detects the collision of the vehicle. And a speed detection sensor (S2, S3) for detecting the ground speed of the column side member such as the breakaway bracket 41, and the ground speed of the column side member is accelerated from the deceleration at the time of a vehicle collision based on signals from these sensors. The energy absorption load is applied to the column side member such as the breakaway bracket 41 by starting the operation at the timing t1 when the acceleration is changed to the deceleration after the change to, and increasing the energy absorption load obtained by the collision energy absorbing device B by a predetermined amount. Electric load increasing device (actuator 51 and shaft 52) Is a load adding means of the gas type. For this reason, it is possible to apply an energy absorption load to the column side member such as the breakaway bracket 41 with high accuracy and with good timing by the load applying means.

  In the first embodiment described above, the collision energy absorbing device B is configured so as to also serve as an electric load adding means. However, the electric load adding means is configured separately from the collision energy absorbing device B. It is also possible to implement. In implementing the present invention, it is also possible to adopt the mechanical load applying means shown in FIGS. 7 and 8 instead of the electric load applying means.

  The mechanical load applying means shown in FIGS. 7 and 8 includes a steel ball 62 and a spring 63 assembled to the outer tube 21 via a holder 61, and energy absorption provided on the inner periphery of the distal end portion of the outer tube 21. A portion 64 is provided. The outer tube 21 is assembled so as to be slidable in the axial direction with respect to the resin ring 23 integrally assembled to the outer periphery of the rear end portion of the inner tube 22.

  The steel ball 62 moves in the front-rear direction in response to a change in the ground speed of the column side member such as the breakaway bracket 41. When the ground speed of the column side member is decelerated during a vehicle collision, the steel ball 62 inertias the spring 63. When the ground speed of the column side member changes from deceleration to acceleration, it is pushed backward by the spring force of the spring 63 (see FIG. 6 (b)). Then, when the ground speed of the column side member changes from acceleration to deceleration thereafter, the column side member bites into the inner periphery of the distal end portion of the outer tube 21 (see FIG. 6C) and does not move forward.

  The energy absorbing portion 64 provided on the inner periphery of the distal end portion of the outer tube 21 is engaged with the steel ball 62 at a timing when the ground speed of the column side member changes from deceleration to acceleration after a vehicle collision, and then changes from acceleration to deceleration. (See (b) of FIG. 6). Thereafter, the steel ball 62 is deformed (see (c) of FIG. 6) to apply an energy absorption load to the column side member. When this mechanical load adding means is adopted, the electric load increasing device (outer tube 51, shaft 52) described above and sensors (S1 to S3) for controlling the operation of the electric load increasing device and electric control are used. An apparatus (ECU) is not required, and the load adding means can be configured simply and inexpensively.

  Moreover, in each said embodiment, what is not provided with the collision energy absorption mechanism which can absorb a driver | operator's collision energy at the time of a vehicle collision by the axial direction contraction of the outer tube 21 and the inner tube 22 of the steering column 20 Although the present invention has been implemented, the present invention can also be implemented in the same manner to those equipped with the collision energy absorption mechanism.

It is the side view which showed 1st Embodiment of the shock absorption type steering column apparatus by this invention. FIG. 2 is an enlarged side view of the shock absorption type steering column device shown in FIG. FIG. 2 is an enlarged plan view of the shock absorption type steering column device (a collision energy absorbing device is omitted) shown in FIG. 1. FIG. 4 is an enlarged rear view taken along line 4-4 of FIG. It is operation | movement explanatory drawing at the time of the secondary collision at the time of a vehicle collision. It is the diagram which showed roughly the change of the ground speed of the body, a crew member, and a column side member at the time of vehicles collision, the amount of movement of a column side member, and a crew member's chest deceleration. It is the principal part side view which showed schematically 2nd Embodiment of the shock absorption type steering column apparatus by this invention. It is action | operation explanatory drawing of the shock absorption type steering column apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Steering shaft, 13 ... Steering wheel, 20 ... Steering column, 31 ... Car body side bracket (vehicle body side member), 41 ... Breakaway bracket (column side member), 51 ... Actuator, 52 ... Shaft, 53 ... Energy absorbing member 54 ... Holder, A ... Airbag device, B ... Collision energy absorbing device, CS ... Connection mechanism, H ... Crew

Claims (3)

A column side member that is assembled to the steering column side that rotatably holds the steering wheel is connected to and supported by a vehicle body side member that is assembled to a part of the vehicle body via a connection mechanism at a set position. When the vehicle receives a load of a predetermined value or more from the occupant toward the front of the vehicle when the vehicle collides, the connection support by the connection mechanism is released and the vehicle is set to move from the set position toward the front of the vehicle. In the impact absorption type steering column device set so that the collision energy absorbing device functions by moving forward and a predetermined energy absorbing load is obtained,
Load applying means for starting an operation at a timing when the ground speed of the column side member changes from deceleration to acceleration and then from acceleration to deceleration after an input from an occupant at the time of a vehicle collision and applying an energy absorption load to the column side member A shock-absorbing steering column device characterized by comprising   2. The shock absorbing steering column apparatus according to claim 1, wherein the load adding means includes a collision detection sensor for detecting a collision of a vehicle, a speed detection sensor for detecting a ground speed of the column side member, and these sensors. Based on this signal, the energy absorption load obtained by the collision energy absorbing device is determined by starting the operation at the timing when the ground speed of the column side member changes from deceleration to acceleration and then changes from acceleration to deceleration at the time of a vehicle collision. An impact-absorbing steering column device comprising an electric load adding device provided with an electric load increasing device for applying an energy absorbing load to the column side member by increasing the amount quantitatively. 2. The shock absorbing steering column apparatus according to claim 1, wherein the load applying means includes a steel ball that moves in the front-rear direction in accordance with a change in ground speed of the column side member, and a spring that controls the movement of the steel ball. The column-side member is engaged with the steel ball at a timing when the ground-side speed of the column-side member changes from deceleration to acceleration and then changes from acceleration to deceleration at the time of a vehicle collision. An impact-absorbing steering column apparatus comprising a mechanical load adding means that is provided with an energy absorbing member that is deformed by the above and that applies an energy absorbing load to the column side member.

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