JP2019156163A - Steering column device - Google Patents

Abstract

To provide a steering column device that is able to easily change a separation load on which a support shaft is sheared.SOLUTION: A lock mechanism 34 comprises: a support shaft 63 extending in a vehicle width direction and having a first shaft part 81 inserted into a first insertion hole 91 formed in a lower jacket 16, and a second shaft part 82 inserted into a second insertion hole 92 formed in the lower jacket 16; and a lock member 65 fitting into the first shaft part 81 and capable of being engaged with or disengaged from a hole in a lock plate 61 according to operation of an operation member. Formed in the first shaft part 81 are first and second annular grooves 87, 88 of different depths, serving as recesses 86. A shearing member 64 is fitted in the first shaft part 81 such that an end on a side of a flange part 101 abuts on a step surface between the first shaft part 81 and the second shaft part 82 and an end on a side opposite to the flange part 101 is radially opposite to the first annular groove 87.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a steering column device.

  2. Description of the Related Art Conventionally, there is a steering column device that has a telescopic adjustment function that adjusts the front-rear position (telescopic position) of a steering wheel in accordance with the physique of a driver. This type of steering column device has a column shaft that is connected to a steering wheel and can be expanded and contracted in the axial direction, a lower jacket supported by the vehicle body, and a lower jacket that can be moved relative to the axial direction (expandable). And a column jacket having a matching upper jacket. The telescopic position of the steering wheel can be adjusted by extending and retracting the column shaft together with the column jacket.

  Some of these steering column devices include a lock mechanism that holds the telescopic position by using a frictional force generated between the lower jacket and the upper jacket by tightening a part of the lower jacket. Further, in recent years, as a locking device, when the impact when the driver collides with the steering wheel due to a vehicle collision (secondary collision) exceeds a predetermined load set in advance, the steering wheel causes the vehicle to move forward. And a function of absorbing a shock caused by a secondary collision is disclosed (for example, Patent Document 1).

  Specifically, the lock mechanism disclosed in Patent Document 1 includes a lock plate that is fixed to the outer periphery of the upper jacket and has a plurality of holes aligned in the axial direction, and is inserted into the insertion hole of the lower jacket and orthogonal to the lower jacket. And a lock member that can be engaged with and disengaged from the hole by rotating the operation member and rotating the operation shaft. The support shaft has a first shaft portion and a second shaft portion that is thicker than the first shaft portion, and a boundary portion between the first shaft portion and the second shaft portion is a weak portion having low strength. The lock member has a cylindrical portion fitted to the first shaft portion and a claw portion extending in a radial direction from the cylindrical portion, and the claw portion is a hole portion in a locked state in which the telescopic position is maintained. In an unlocked state in which the telescopic position can be adjusted by engaging, the claw part is detached from the hole part. When the load acting on the upper jacket due to the secondary collision exceeds a predetermined load, the cylindrical portion of the lock member functions as a shearing member that shears the support shaft, and a boundary portion between the first shaft portion and the second shaft portion And shearing the middle of the first shaft portion. As a result, the steering wheel can move forward of the vehicle against the frictional force generated between the lower jacket and the upper jacket, and the impact of the secondary collision is absorbed.

Japanese Patent Laying-Open No. 2015-182614

  By the way, in the structure of the above-mentioned Patent Document 1, when changing the separation load at which the support shaft is sheared, the thickness of the first shaft portion must be changed in order to change the strength of the fragile portion. In addition, it is necessary to change the hole diameter of the insertion hole of the lower jacket into which the first shaft portion is inserted. As a result, there is a problem that the number of design change points for changing the separation load increases and the manufacturing cost increases.

  The objective of this invention is providing the steering column apparatus which can change easily the detachment load by which a support shaft is sheared.

  A steering column device that solves the above-described problems has a steering wheel fixed at one end, a column shaft that can extend and contract in the axial direction, a lower jacket supported by the vehicle body, and a relative movement in the axial direction relative to the lower jacket. A column jacket having a fitting upper jacket and rotatably supporting the column shaft, a plurality of holes provided in an axial direction on the outer periphery of the upper jacket, and extending in a direction crossing the axial direction A support shaft having a first shaft portion inserted into a first insertion hole formed in the lower jacket, and a second shaft portion inserted into a second insertion hole formed in the lower jacket, and the first shaft A lock member that is fitted to the shaft portion and can be engaged with and disengaged from the hole portion in accordance with an operation of the operation member, and is provided on the outer peripheral surface of the first shaft portion with another axial position of the first shaft portion. Than A concave portion is formed so as to reduce the cross-sectional area, and a cylindrical shearing member is fitted to the outer periphery of the first shaft portion, and at least one axial end of the shearing member faces the concave portion, The first shaft portion is configured to be shearable in the concave portion by an impact load in the axial direction of the column shaft and the column jacket.

  According to the said structure, the weak part of a 1st axial part turns into a part in which the recessed part was formed, and the end of the axial direction of a shearing member opposes this weak part. Therefore, when an impact load in the axial direction is applied due to a secondary collision in a state where the lock member is engaged with the hole of the lock plate, the first shaft portion includes a recess facing one end of the shear member and the other end of the shear member. Is sheared at the opposite part. Thus, since the first shaft portion is sheared at the portion where the recess is formed, the load by which the first shaft portion is sheared depends on the depth of the recess (cross-sectional area at the position where the recess is formed). change. Therefore, by adjusting the depth of the recess formed in the first shaft portion, the diameter of the first insertion hole does not need to be changed as in the case of changing the outer diameter of the entire first shaft portion, for example, and the support shaft It is possible to easily change the separation load at which the shearing force is sheared.

  In the steering column device, a plurality of the recesses having different recess sizes are formed on an outer peripheral surface of the first shaft portion, and one of the plurality of recesses faces one end of the shearing member, and the other It is preferable that a recessed part is located in the inner periphery of the said shear member or the said 1st insertion hole.

  According to the said structure, since a detachment load can be changed by making the recessed part from which a depth differs facing one end of a shearing member, a several detachment load can be set with a single support shaft. Therefore, even when the steering column device is mounted on a plurality of different vehicle types, the separation load of the support shaft can be easily changed according to the specifications, and the effect is great.

In the steering column device, the recess is preferably an annular groove extending in a circumferential direction of the support shaft.
According to the above configuration, since the concave portion is an annular groove, the support shaft can be stably sheared when an impact load is applied regardless of the relative circumferential position (rotation phase) of the support shaft with respect to the shearing member.

  In the steering column device, a thread is formed on an outer peripheral surface of at least one of the first shaft portion and the second shaft portion, and at least one of the first insertion hole and the second insertion hole has the It is preferable that a screw groove into which the screw thread is screwed is formed.

  According to the above configuration, the axial position of the support shaft with respect to the lower jacket of the support shaft can be easily changed by screwing and retracting the support shaft in the first and second insertion holes. Therefore, when applied to a configuration in which a plurality of concave portions having different depths are formed in the first shaft portion, one end of the shearing member can be easily opposed to the concave portion having a desired depth, which is particularly effective. Is.

  In the steering column device, a positioning member that fits at least one of the first shaft portion and the second shaft portion on an outer peripheral surface of the support shaft and defines an axial position of the support shaft with respect to the lower jacket. Is preferably provided.

  According to the said structure, the axial direction position of this support shaft with respect to the lower jacket of a support shaft can be set to arbitrary positions with a simple structure. Therefore, when applied to a configuration in which a plurality of recesses having different depths are formed in the first shaft portion, it becomes possible to make one end of the shearing member face the recess having a desired depth with a simple configuration, It is particularly effective.

  According to the present invention, the separation load can be easily changed.

Sectional drawing along the axial direction of the steering column apparatus of 1st Embodiment. Sectional drawing orthogonal to the axial direction in the fastening shaft | axis part in the steering column apparatus of 1st Embodiment (II-II sectional view taken on the line of FIG. 1). Sectional drawing orthogonal to the axial direction in the support shaft part in the steering column apparatus of 1st Embodiment (III-III sectional view taken on the line of FIG. 1). (A) is sectional drawing along the axial direction of the locking mechanism vicinity in a locked state, (b) is sectional drawing along the axial direction of the locking mechanism vicinity in an unlocked state. (A) is a sectional view of the first annular groove in the support shaft (Va-Va sectional view of FIG. 3), (b) is a sectional view of the second annular groove (Vb-Vb sectional view of FIG. 3), (C) is sectional drawing in parts other than a 1st and 2nd annular groove similarly (Vc-Vc sectional drawing of FIG. 3). The expanded sectional view orthogonal to the axial direction in the support shaft part in the steering column apparatus of 1st Embodiment. The expanded sectional view orthogonal to the axial direction of the state which changed the detachment load of the support shaft in the steering column apparatus of 1st Embodiment. The expanded sectional view orthogonal to the axial direction in the support shaft part in the steering column apparatus of 2nd Embodiment.

(First embodiment)
Hereinafter, a first embodiment of a steering column device will be described with reference to the drawings.
As shown in FIG. 1, the steering column device 1 includes a column jacket 2 supported by the vehicle body S and a column shaft 3 rotatably supported in the column jacket 2. A steering wheel 4 is connected to an end of the column shaft 3 on the vehicle rear side (right side in FIG. 1). On the other hand, a steering mechanism (both not shown) such as a rack and pinion mechanism is connected to the front end (left side in FIG. 1) of the column shaft 3 via an intermediate shaft. Then, the rotation of the column shaft 3 accompanying the steering operation is transmitted to the steering mechanism, whereby the steering angle of the steered wheels (not shown) is changed.

  The steering column device 1 also has a tilt function for adjusting the height position (tilt position) of the steering wheel 4 and a telescopic function for adjusting the front-rear position (telescopic position) of the steering wheel 4.

  Specifically, the column shaft 3 is movable relative to the upper shaft 11 in the axial direction by being splined to the cylindrical upper shaft 11 to which the steering wheel 4 is coupled and the inner periphery of the upper shaft 11. A cylindrical lower shaft 12 is provided. That is, the column shaft 3 can be expanded and contracted in the axial direction.

  The column jacket 2 includes a cylindrical upper jacket 14 that rotatably supports the upper shaft 11 via a rolling bearing 13, and a cylindrical lower jacket 16 that rotatably supports the lower shaft 12 via a rolling bearing 15. It has. The upper jacket 14 is fitted to the inner periphery of the lower jacket 16 so as to be movable in the axial direction, and the column jacket 2 can be expanded and contracted in the axial direction. Accordingly, the telescopic position can be adjusted by moving the upper jacket 14 and the upper shaft 11 relative to the lower jacket 16 and the lower shaft 12 and changing the position of the steering wheel 4 in the axial direction of the column shaft 3. It has become.

  A support portion 21 that protrudes upward of the vehicle is formed at the vehicle front side end portion of the lower jacket 16, and a shaft hole 22 that penetrates in the vehicle width direction (the direction orthogonal to the plane of FIG. 1) is formed in the support portion 21. Has been. Further, the lower jacket 16 is formed with an elongated hole-like opening 23 that opens above the vehicle and extends in the axial direction thereof.

  A stopper 24 that is inserted into the opening 23 is fixed to the vehicle front side end of the upper jacket 14. That is, the column jacket 2 is configured to be extendable until the stopper 24 of the upper jacket 14 contacts the inner edge of the opening 23 on the vehicle front side.

  The lower jacket 16 is supported so as to be tiltable about a tilt support shaft 32 inserted into the shaft hole 22 via a lower bracket 31 fixed to the vehicle front side of the vehicle body S. Thus, the tilt position can be adjusted by changing the position of the steering wheel 4 in the tilt direction (strictly speaking, the tilt direction about the tilt support shaft 32), which is the substantially vertical direction of the vehicle. Yes. Further, the lower jacket 16 is supported so as to be tiltable about the tilt support shaft 32 within a predetermined range via an upper bracket 33 fixed to the vehicle rear side of the vehicle body S. The upper bracket 33 is provided with a lock mechanism 34 that holds the tilt position and the telescopic position of the steering wheel 4.

  As shown in FIGS. 1 and 2, the lock mechanism 34 includes a tightening shaft 42 that rotates integrally with an operation lever 41 that is operated by a driver, and an upper bracket according to the rotation operation of the operation lever 41. The tilt position and the telescopic position are maintained by the frictional force acting between 33 and the lower jacket 16 and between the lower jacket 16 and the upper jacket 14.

  Specifically, the upper bracket 33 is formed in a substantially rectangular shape when viewed in the axial direction, and has a flat top plate portion 43 fixed to the vehicle body S and a pair of side plate portions extending from the top plate portion 43 to the vehicle lower side. 44a and 44b. The upper bracket 33 is fixed by fastening the top plate portion 43 to the vehicle body S with fastening bolts (not shown). The side plate portions 44a and 44b are fixed to the top plate portion 43 with an interval in the vehicle width direction, and the lower jacket 16 is sandwiched therebetween. The side plate portions 44a and 44b are respectively formed with tilt long holes 45a and 45b extending in the tilt direction at positions facing each other in the vehicle width direction.

  The lower jacket 16 has a substantially rectangular parallelepiped arm portion 46a, 46b and an arm portion 46a, 46b that protrudes downward from the vehicle and is spaced apart in the vehicle width direction. A wide slit 47 penetrating through is formed. In the arm portions 46a and 46b, through holes 48a and 48b penetrating in the vehicle width direction are formed at positions facing the tilt long holes 45a and 45b in the same direction.

  The fastening shaft 42 is made of a metal material and includes a head 51 and a shaft-shaped main body 52 extending from the head 51 in the vehicle width direction. The tightening shaft 42 has a head portion 51 protruding outward in the vehicle width direction with respect to the side plate portion 44a (left side in FIG. 2), and a tip end portion of the main body portion 52 outward in the vehicle width direction with respect to the side plate portion 44b (FIG. 2). In the state of projecting to the right and the middle, the tilt elongated holes 45a and 45b and the through holes 48a and 48b are inserted. As a result, the upper jacket 14 (column jacket 2) can tilt in the tilt direction within the range in which the tilt long holes 45a and 45b are formed.

  Disk-shaped first and second cam plates 53 and 54 are interposed between the head portion 51 of the main body portion 52 and the arm portion 46 a of the lower jacket 16. Cam protrusions (not shown) are formed on the opposing surfaces of the first and second cam plates 53 and 54, respectively. The first cam plate 53 is fitted to the main body 52 so as to be rotatable integrally with the operation lever 41 and the fastening shaft 42 by the turning operation of the operation lever 41, and the second cam plate 54 is relatively moved around the fastening shaft 42. The main body 52 is rotatably fitted. A disc-shaped collar 55, a part of which is inserted into the tilt long hole 45 b, is mounted on the opposite side of the main body 52 from the head 51 side. In addition, a nut 57 is fixed to the tip of the main body 52 with a thrust bearing 56 interposed between the collar 55.

  Thereby, through the turning operation of the operation lever 41, the state is switched between the state where the respective cam protrusions of the first and second cam plates 53 and 54 are riding on each other and the state where the riding is released. In the locked state in which the cam projections of the first and second cam plates 53 and 54 ride on each other, the arm portions 46a and 46b are pressed against the side plate portions 44a and 44b so that the distance therebetween is reduced. Tightened. Along with this, the inner peripheral portion of the lower jacket 16 is elastically deformed in such a manner that the diameter is reduced, and the inner periphery of the lower jacket 16 is pressed against the outer periphery of the upper jacket 14. In the locked state, the upper bracket 33 and the lower jacket are caused by the frictional force acting between the arm portions 46a, 46b and the side plate portions 44a, 44b and the frictional force acting between the lower jacket 16 and the upper jacket 14. 16 and relative movement between the lower jacket 16 and the upper jacket 14 are restricted. Thereby, the tilt position and telescopic position of the steering wheel 4 are maintained.

  On the other hand, in the unlocked state in which the cam protrusion of the first and second cam plates 53 and 54 is released, the arm portions 46a and 46b are not pressed by the side plate portions 44a and 44b, and the arm portions 46a and 46b are tightened. Is released. Along with this, the press contact of the lower jacket 16 with the upper jacket 14 is also released. Thus, in the unlocked state, the frictional force acting between the arm portions 46a, 46b and the side plate portions 44a, 44b and the frictional force acting between the lower jacket 16 and the upper jacket 14 become sufficiently small. Relative movement between the upper bracket 33 and the lower jacket 16 and relative movement between the lower jacket 16 and the upper jacket 14 are allowed. Thereby, the tilt position and the telescopic position of the steering wheel 4 can be adjusted.

  As shown in FIGS. 1, 3, and 4, the lock mechanism 34 includes a lock plate 61, a cam member 62 fitted to the tightening shaft 42, and a support shaft provided in front of the tightening shaft 42. 63, a shearing member 64 fitted to the support shaft 63, a lock member 65 fitted to the support shaft 63 via the shearing member 64, and a biasing member 66 that biases the lock member 65. Yes.

  The lock plate 61 is formed in a curved plate shape that extends in the axial direction of the upper jacket 14 and is curved along the circumferential direction thereof. The lock plate 61 is fixed to a portion of the outer peripheral surface of the upper jacket 14 exposed from the slit 47 of the lower jacket 16 by welding or the like.

  The lock plate 61 has a ladder shape in which a plurality of holes 71 are formed at equal intervals in the axial direction, and a partition 72 is formed between adjacent holes 71. Each hole 71 is formed in a substantially square hole shape that penetrates in the plate thickness direction of the lock plate 61 and extends in the circumferential direction of the upper jacket 14. In addition, a plate portion 73 that does not have the hole 71 is formed at the vehicle rear side end portion of the lock plate 61, and the vehicle rear side end of the plate portion 73 is bent downward in the vehicle. Is formed. A substantially rectangular parallelepiped damper 75 made of an elastic body such as an elastomer is fixed to the outer surface of the plate portion 73. The thickness of the damper 75 is set substantially equal to the height of the refracting portion 74.

  As shown in FIGS. 2 and 4, the cam member 62 is fitted to a portion of the fastening shaft 42 exposed in the slit 47 of the lower jacket 16 so as to be integrally rotatable. The cam member 62 has a cylindrical portion 76 fitted to the fastening shaft 42, and a cam portion 77 and a protrusion 78 formed on the outer peripheral surface of the cylindrical portion 76. The cam portion 77 and the protrusion 78 are formed on the cylindrical portion 76 so as to protrude substantially opposite to each other. The cam portion 77 is located in a region opposite to the lower jacket 16 with respect to the cylindrical portion 76, and the protrusion 78 is located in a region on the lower jacket 16 side. The cam portion 77 is formed in a substantially triangular shape that narrows toward the outside in the radial direction of the cylindrical portion 76 as viewed in the vehicle width direction (viewed in the axial direction of the cylindrical portion 76). It is set approximately equal to the diameter. The protrusion 78 is formed in a substantially triangular shape smaller than the cam portion 77 when viewed in the vehicle width direction. In the locked state shown in FIG. 4A, the protrusion 78 does not interfere with the movement locus R of the damper 75 indicated by a broken line in FIG. 4B. In the unlocked state shown in FIG. Interference on the movement track R on the vehicle rear side. Thereby, contraction of the column jacket 2 is restricted at a position where the damper 75 abuts against the protrusion 78 in the unlocked state.

  As shown in FIGS. 3 and 4, the support shaft 63 is made of a resin material and is formed in a substantially cylindrical shape extending in the vehicle width direction, which is a direction orthogonal to the axial direction of the column jacket 2. The support shaft 63 includes a first shaft portion 81, a second shaft portion 82 having a larger outer diameter than the first shaft portion 81, and a spring portion 83 that can be elastically deformed in the vehicle width direction (the axial direction of the support shaft 63). have. The 1st axial part 81, the 2nd axial part 82, and the spring part 83 are provided in this order in the axial direction. The spring portion 83 is formed in a thin strip shape, and both ends thereof are connected to the outer peripheral edge portion of the second shaft portion 82 to form a substantially arc shape. A first thread 84 is formed on the outer peripheral surface of the end portion of the first shaft portion 81 on the side opposite to the second shaft portion 82. A second thread 85 is formed on the outer peripheral surface of the second shaft portion 82 over substantially the entire axial direction. A plurality of concave portions 86 are formed on the outer periphery of the first shaft portion 81 so as to have a smaller cross-sectional area than other axial positions of the first shaft portion 81.

  Specifically, as shown in FIG. 3, first and second annular grooves 87 and 88 having different depths are formed as the recesses 86. The first and second annular grooves 87 and 88 are each formed in an annular shape extending in the circumferential direction of the support shaft 63. Further, as shown in FIGS. 5A and 5B, the first annular groove 87 has a depth along the radial direction that is deeper than the second annular groove 88, and the first shaft portion 81. The sectional area of the first annular groove 87 is set smaller than the sectional area of the second annular groove 88. As a result, the first shaft portion 81 breaks at the first annular groove 87 portion when a load greater than or equal to a preset first separation load acts on the first annular groove 87 portion, and the first annular groove 88 portion first When a load greater than the second separation load greater than the separation load acts, the second annular groove 88 breaks. As shown in FIGS. 5A to 5C, the cross-sectional area of the first shaft portion 81 where the first and second annular grooves 87 and 88 are not formed is the first and second annular grooves. It is larger than the cross-sectional area in the 87, 88 portion, and the separation load is larger than the first and second separation loads. That is, the first and second annular grooves 87 and 88 become weak portions where the strength is locally weakened in the support shaft 63. Further, since the first shaft portion 81 of the support shaft 63 is thinner than the second shaft portion 82, it becomes a fragile portion as compared with the second shaft portion 82.

  As shown in FIG. 3, first and second insertion holes 91 and 92 into which the support shaft 63 is inserted are formed in the arm portions 46 a and 46 b of the lower jacket 16. The first and second insertion holes 91 and 92 penetrate the arm portions 46a and 46b in the vehicle width direction. The first insertion hole 91 has a first enlarged diameter portion 93 and a smaller diameter than the first enlarged diameter portion 93 from the vehicle width direction outer side (left side in FIG. 3), and is screwed into the first screw thread 84. A thread groove 94 is formed. Further, the second insertion hole 92 is smaller in diameter than the second enlarged diameter portion 95 and the second enlarged diameter portion 95 from the outer side in the vehicle width direction (right side in FIG. 3), and is screwed into the second thread 85. A second thread groove 96 is formed. The support shaft 63 is inserted by screwing into the first and second insertion holes 91 and 92 from the vehicle width direction outer side of the arm portion 46b. In the state shown in FIG. 3, the second annular groove 88 is the first annular groove 88. Located in the insertion hole 91, the first annular groove 87 is located at the opening end of the first insertion hole 91 on the inner side in the vehicle width direction. Note that the spring portion 83 is accommodated in a compressed state in the second enlarged diameter portion 95.

  The shearing member 64 is made of a metal material and has a substantially cylindrical shape. An annular flange portion 101 extending outward in the radial direction is formed on the arm portion 46 b side of the shearing member 64. Note that the outer diameter of the flange portion 101 is set to be approximately equal to the outer diameter of the second shaft portion 82. In the state shown in the figure, the shearing member 64 has the flange portion 101 in contact with the step surface between the first shaft portion 81 and the second shaft portion 82, and the opposite flange portion 101 side has the diameter of the first annular groove 87. The first shaft portion 81 is fitted so as to face each other in the direction.

  As shown in FIGS. 3 and 4, the lock member 65 includes a cylindrical cylindrical portion 111, and a lock portion 112 and a contact portion 113 that extend radially outward from the outer peripheral surface of the cylindrical portion 111. And is fitted to the outer periphery of the support shaft 63 via a shearing member 64. The outer diameter of the cylindrical portion 111 is set to be approximately equal to the outer diameter of the flange portion 101 of the shearing member 64, and the axial length of the cylindrical portion 111 is set slightly shorter than the axial length of the shearing member 64. Yes. The lock portion 112 extends substantially linearly along the radial direction of the cylindrical portion 111, and a claw portion 114 that can be engaged with and disengaged from the hole portion 71 is formed at the tip of the lock portion 112. The abutting portion 113 extends substantially linearly along the radial direction of the cylindrical portion 111 from a position below the vehicle with respect to the lock portion 112, and faces the cam member 62 in the axial direction of the column jacket 2. The front end of the abutting portion 113 is formed in an arc shape that abuts against the cam member 62 and is pushed downward when the cam member 62 rotates clockwise as viewed in the vehicle width direction.

  A torsion coil spring is employed for the biasing member 66 of the present embodiment. The urging member 66 is attached to the outer peripheral surface of the lock member 65 so that the lock member 65 rotates in the direction in which the lock portion 112 approaches the lock plate 61 side (counterclockwise in FIG. 4). Yes.

  As shown in FIG. 4A, when the operation lever 41 is operated so that the lock mechanism 34 is in the locked state, as described above, between the side plate portions 44a, 44b and the arm portions 46a, 46b, and the lower A frictional force is generated between the jacket 16 and the upper jacket 14 to maintain the tilt position and the telescopic position. At this time, the cam member 62 and the lock member 65 are not in contact with each other, and the lock member 65 is urged by the urging member 66 in a direction in which the lock portion 112 is close to the lock plate 61 side. Engage with any of the plurality of holes 71. In order to restrict (lock) the telescopic operation performed by the driver to adjust the telescopic position, the frictional force between the lower jacket 16 and the upper jacket 14 accompanying the tightening of the pair of arm portions 46a and 46b is used. It is enough.

  As shown in FIG. 4B, when the operation lever 41 is operated so that the lock mechanism 34 is unlocked, the tightening of the arm portions 46a and 46b by the side plate portions 44a and 44b is released as described above. The At this time, as the fastening shaft 42 that rotates integrally with the operation lever 41 rotates, the cam member 62 pushes down the contact portion 113 of the lock member 65 downward, and the claw portion 114 moves away from the lock plate 61. Then, the lock member 65 rotates. Thereby, the engagement of the claw portion 114 with the hole portion 71 is released, and the tightening of the pair of arm portions 46a and 46b is released, and the telescopic operation is allowed.

Next, the operation of the lock mechanism 34 when the vehicle collides in the locked state will be described.
As shown in FIG. 1, a collision load due to a so-called secondary collision acts on the column shaft 3 and the column jacket 2 in the axial direction at the time of a vehicle collision, and the upper jacket 14 and the upper shaft 11 tend to contract. Accordingly, a collision load from the steering wheel 4 side acts on the lock member 65 engaged with the hole 71 of the lock plate 61 via the claw 114. Depending on the adjusted telescopic position (relative position of the upper jacket 14 with respect to the lower jacket 16), the claw portion 114 may not be engaged with the hole portion 71 and may be in contact with the partition portion 72. As the upper jacket 14 moves in the axial direction, the claw 114 immediately engages with the hole 71.

  When a load greater than or equal to the first separation load is applied from the lock member 65 to the support shaft 63 due to the secondary collision, the end surface of the shearing member 64 on the side opposite to the flange 101 functions as a shearing blade, as shown by a thick line in FIG. Then, the support shaft 63 is sheared in the first annular groove 87 serving as the fragile portion. At this time, since the entire first shaft portion 81 becomes a weak portion as compared with the second shaft portion 82, the end surface of the shearing member 64 on the flange portion 101 side functions as a cutting blade, and in the first shaft portion 81, A boundary portion with the second shaft portion 82 is sheared. The portion of the support shaft 63 where the second annular groove 88 is formed is not sheared because it is located in the first insertion hole 91. As the support shaft 63 is sheared, the lock member 65 (claw 114) is disengaged from the hole 71, and the column jacket 2 resists the frictional force generated between the lower jacket 16 and the upper jacket 14. Can be shrunk and the impact load is absorbed.

Next, in the steering column device 1 of the present embodiment, a case where the separation load of the support shaft 63 is changed will be described.
As shown in FIG. 7, when the steering column device 1 is assembled, the insertion position of the support shaft 63 into the first and second insertion holes 91 and 92, that is, the position of the support shaft 63 in the vehicle width direction with respect to the lower jacket 16 is changed. Then, the second annular groove 88 is positioned at the opening end of the first insertion hole 91 on the inner side in the vehicle width direction, and the first annular groove 87 is opposed to the inner peripheral surface of the shearing member 64. Further, the end of the shearing member 64 on the side opposite to the flange 101 is opposed to the second annular groove 88.

  In the steering column device 1 assembled in this way, when a load greater than or equal to the second separation load is applied from the lock member 65 to the support shaft 63 due to a secondary collision, the end surface of the shearing member 64 on the side opposite to the flange 101 functions as a shearing blade. Then, the support shaft 63 is sheared in the second annular groove 88 serving as the fragile portion. At this time, the end surface of the shearing member 64 on the flange portion 101 side functions as a cutting blade, and the end portion of the first shaft portion 81 on the second shaft portion 82 side is sheared. The portion of the support shaft 63 where the first annular groove 87 is formed is not sheared because it is located in the shearing member 64.

The operation and effect of this embodiment will be described.
(1) Since the concave portion 86 (first and second annular grooves 87 and 88) is formed in the first shaft portion 81, the fragile portion of the first shaft portion 81 becomes a portion in which the concave portion 86 is formed, and shearing occurs in this fragile portion. The end of the member 64 on the side opposite to the flange 101 is opposed. Therefore, the separation load at which the first shaft portion 81 is sheared varies depending on the depth of the recess 86 (cross-sectional area at the position where the recess 86 is formed). Therefore, by adjusting the depth of the recess 86 formed in the first shaft portion 81, for example, without changing the hole diameter of the first insertion hole 91 as in the case of changing the outer diameter of the entire first shaft portion 81, for example. The separation load at which the support shaft 63 is sheared can be easily changed.

  (2) Since the first and second annular grooves 87 and 88 having different recess sizes are formed as the recesses 86 on the outer peripheral surface of the support shaft 63, any one of the first and second annular grooves 87 and 88 is a shearing member. The separation load can be changed by facing one end of 64. Therefore, a plurality of separation loads can be set with a single support shaft 63. Thereby, even when the steering column device 1 is mounted on a plurality of different vehicle types, the separation load of the support shaft 63 can be easily changed according to the specifications, and the effect is great.

  (3) Since the recess 86 is formed as the annular first and second annular grooves 87 and 88 extending in the circumferential direction of the support shaft 63, the relative circumferential position (rotation phase) of the support shaft 63 with respect to the shearing member 64 Regardless, the support shaft 63 can be stably sheared when an impact load is applied.

  (4) First and second screw threads 84 and 85 are formed on the outer peripheral surfaces of the first and second shaft portions 81 and 82, and the first and second screw threads 84 are formed in the first and second insertion holes 91 and 92. , 85 are screwed to form first and second thread grooves 94, 96. Therefore, the vehicle width direction position of the support shaft 63 with respect to the lower jacket 16 (the axial position of the support shaft 63) can be easily changed by screwing the support shaft 63 back and forth in the first and second insertion holes 91 and 92. . In the present embodiment, since the first and second annular grooves 87 and 88 having different depths are formed in the first shaft portion 81, the end portions on the side opposite to the flange portion 101 of the shearing member 64 can be easily formed in the first and second portions. It is possible to oppose either one of the annular grooves 87 and 88, which is particularly effective.

(Second Embodiment)
Next, a second embodiment of the steering column device will be described with reference to the drawings. For convenience of explanation, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 8, the support shaft 63 of the present embodiment includes a first shaft portion 81 and a second shaft portion 82 and does not have a spring portion 83. The first and second shaft portions 81 and 82 and the first and second threads 84 and 85 are not formed, and the outer peripheral surface of the end portion of the first shaft portion 81 on the side opposite to the second shaft portion 82, and the first The outer peripheral surfaces of the biaxial portions 82 are each formed in a cylindrical shape. Further, the first and second screw grooves 94 and 96 are not formed on the inner peripheral surfaces of the first and second insertion holes 91 and 92, and the inner peripheral surface of the first insertion hole 91 on the inner side in the vehicle width direction. The inner peripheral surface of the second insertion hole 92 on the inner side in the vehicle width direction is formed in a cylindrical shape having an inner diameter substantially equal to the outer diameter of the first and second shaft portions 81 and 82, respectively.

  The support shaft 63 is inserted from the outer side in the vehicle width direction of the arm portion 46 b, the second annular groove 88 is located in the first insertion hole 91, and the first annular groove 87 is located on the inner side in the vehicle width direction of the first insertion hole 91. Located at the open end. Then, push nuts 121 and 122 as positioning members are fitted into the portion projecting into the first enlarged portion 93 in the first shaft portion 81 and the portion projecting into the second enlarged portion 95 in the second shaft portion 82, respectively. As a result, the position of the support shaft 63 in the vehicle width direction is defined.

  In the steering column device 1 shown in the figure, as in the first embodiment, when a load greater than or equal to the first separation load acts on the support shaft 63 from the lock member 65 due to a secondary collision, the support shaft 63 is sheared. Further, the position of the support shaft 63 in the vehicle width direction is changed, the second annular groove 88 is positioned at the opening end on the inner side in the vehicle width direction of the first insertion hole 91, and the first annular groove 87 is positioned in the shearing member 64. Thus, when a load greater than or equal to the second detachment load acts on the support shaft 63 from the lock member 65, the support shaft 63 is sheared.

Next, the effect of this embodiment will be described. In addition to the effects (1) to (3) of the first embodiment, the present embodiment has the following effects.
(5) Since the push nuts 121 and 122 for fitting the first and second shaft portions 81 and 82 to define the vehicle width direction position of the support shaft 63 are provided on the outer peripheral surface of the support shaft 63, the configuration is simple. The vehicle width direction position of the support shaft 63 with respect to the lower jacket 16 (the axial direction position of the support shaft 63) can be set to an arbitrary position. In this embodiment, since the first and second annular grooves 87 and 88 having different depths are formed in the first shaft portion 81, the first and second annular grooves 87 and 88 have a simple configuration at one end of the shearing member 64. It is possible to oppose any one of these, which is particularly effective.

This embodiment can be implemented with the following modifications. This embodiment and the following modifications can be implemented in combination with each other within a technically consistent range.
In the first embodiment, only one of the first and second screw threads 84 and 85 is formed on the support shaft 63, and one of the corresponding first and second screw grooves 94 and 96 is first inserted. The hole 91 or the second insertion hole 92 may be formed.

In the second embodiment, only one of the push nuts 121 and 122 may be fitted to the support shaft 63 to define the position of the support shaft 63 in the vehicle width direction.
In the second embodiment, the push nuts 121 and 122 are used as positioning members. However, the present invention is not limited to this. For example, the first and second screw threads 84 and 85 are formed on the support shaft 63, and the first positioning member is the first. And a nut threadedly engaged with the second threads 84 and 85 may be used.

  In the first embodiment, the support shaft 63 is screwed into the first and second insertion holes 91 and 92 to define the position in the vehicle width direction. In the second embodiment, the push nuts 121 and 122 are The position of the support shaft 63 in the vehicle width direction was defined by using this. However, the present invention is not limited to this, and the vehicle width direction position of the support shaft 63 with respect to the lower jacket 16 may be defined by press-fitting the support shaft 63 into the first and second insertion holes 91 and 92, for example. The positioning mode can be changed as appropriate.

In the first embodiment, the spring portion 83 may not be provided on the support shaft 63. In the second embodiment, the support shaft 63 may be provided with the spring portion 83.
In each of the above embodiments, the position at which the damper 75 abuts the protrusion 78 is the foremost end of the adjustable telescopic position. However, the present invention is not limited to this. The position of the lock member 65 that contacts the lock portion 112 may be the foremost end of the adjustable telescopic position.

  In each of the above embodiments, the plurality of hole portions 71 are provided in the lower jacket 16 by fixing the lock plate 61 to the lower jacket 16. However, the present invention is not limited thereto, and for example, the plurality of hole portions 71 are provided in the lower jacket 16. You may form directly.

  In each of the above embodiments, the first and second annular grooves 87 and 88 are further formed at the end of the first shaft portion 81 on the second shaft portion 82 side, and both ends of the shearing member 64 are the first and second annular portions. You may make it oppose any one of the groove | channels 87 and 88. FIG.

  In each of the above embodiments, the first and second annular grooves 87 and 88 are formed as the recesses 86. However, the present invention is not limited to this. For example, the first annular groove 87 is not formed, and only the second annular groove 88 is formed. May be. That is, the first shaft portion 81 may be provided with only a single recess 86 without providing the plurality of recesses 86. Further, the first shaft portion 81 may be provided with three or more concave portions 86 having different depths.

  In each of the above-described embodiments, the first and second annular grooves 87 and 88 extending over the entire circumference of the first shaft portion 81 are the recesses 86. However, the present invention is not limited to this. A groove extending only over a range may be used as the recess 86. The recess 86 is not limited to the groove shape, and may be, for example, a hole extending in a direction orthogonal to the axial direction of the support shaft 63, and is recessed so that the cross-sectional area of the first shaft portion 81 is smaller than other axial positions. In this case, the shape of the recess 86 can be changed as appropriate.

  In each of the above embodiments, the lock member 65 is fitted to the first shaft portion 81 via the shearing member 64. However, the present invention is not limited to this, and the lock member 65 may be directly fitted to the first shaft portion 81. . In this case, the lock member 65 functions as a shear member.

  In each of the above embodiments, the outer diameter of the first shaft portion 81 is set smaller than the outer diameter of the second shaft portion 82. However, the present invention is not limited to this, and for example, the outer diameter of the first shaft portion 81 is set to the second shaft portion. It may be set equal to or larger than the outer diameter of 82.

  In each of the above embodiments, the support shaft 63 is provided on the lower jacket 16 so as to extend in the vehicle width direction. However, the present invention is not limited to this, and the crossing with the axial direction of the column jacket 2 is not limited to this. It may be provided so as to extend in the intersecting direction.

  DESCRIPTION OF SYMBOLS 1 ... Steering column apparatus, 2 ... Column jacket, 3 ... Column shaft, 4 ... Steering wheel, 11 ... Upper shaft, 12 ... Lower shaft, 14 ... Upper jacket, 16 ... Lower jacket, 31 ... Lower bracket, 33 ... Upper bracket 34 ... Lock mechanism, 41 ... Operation lever, 42 ... Clamping shaft, 44a, 44b ... Side plate, 45a, 45b ... Tilt long hole, 46a, 46b ... Arm, 47 ... Slit, 48a, 48b ... Through-hole, DESCRIPTION OF SYMBOLS 61 ... Lock plate, 62 ... Cam member, 63 ... Support shaft, 64 ... Shear member, 65 ... Lock member, 66 ... Biasing member, 71 ... Hole part, 76 ... Cylindrical part, 77 ... Cam part, 78 ... Projection part , 81 ... 1st shaft part, 82 ... 2nd shaft part, 83 ... Spring part, 84 ... 1st thread, 85 ... 2nd thread, 86 ... Recessed part, 87 ... 1st annular groove, 88 ... 2nd ring Groove, 91 ... first insertion hole, 92 ... second insertion hole, 94 ... first screw groove, 96 ... second screw groove, 111 ... cylindrical part, 112 ... lock part, 113 ... contact part, 114 ... claw part 121, 122 ... push nut (positioning member), S ... vehicle body.

Claims (5)

A steering wheel is fixed to one end, and a column shaft that can extend and contract in the axial direction;
A lower jacket supported by a vehicle body, and an upper jacket that is fitted to the lower jacket so as to be relatively movable in the axial direction, and a column jacket that rotatably supports the column shaft;
A plurality of holes provided in an axial direction on the outer periphery of the upper jacket;
A first shaft portion that extends in a direction intersecting the axial direction and is inserted into a first insertion hole formed in the lower jacket, and a second shaft portion that is inserted into a second insertion hole formed in the lower jacket. A support shaft having,
A locking member that fits into the first shaft portion and can be engaged with and disengaged from the hole portion according to an operation of the operation member;
On the outer peripheral surface of the first shaft portion, there is formed a recess that is recessed so that the cross-sectional area is smaller than the other axial position in the first shaft portion,
A cylindrical shearing member is fitted to the outer periphery of the first shaft portion, and at least one axial end of the shearing member is opposed to the recess, and is caused by an axial impact load of the column shaft and the column jacket. A steering column device configured to be able to shear the first shaft portion in the recess. In the steering column device according to claim 1,
On the outer peripheral surface of the first shaft portion, a plurality of the recesses having different recess sizes are formed,
A steering column device in which one of the plurality of recesses faces one end of the shear member, and the other recess is located on the inner periphery of the shear member or the first insertion hole. In the steering column device according to claim 1 or 2,
The steering column device, wherein the recess is an annular groove extending in a circumferential direction of the support shaft. In the steering column device according to any one of claims 1 to 3,
On at least one outer peripheral surface of the first shaft portion and the second shaft portion, a screw thread is formed,
A steering column device, wherein a screw groove into which the screw thread is screwed is formed in at least one of the first insertion hole and the second insertion hole. In the steering column device according to any one of claims 1 to 3,
A steering column provided on the outer peripheral surface of the support shaft with a positioning member that fits at least one of the first shaft portion and the second shaft portion and defines an axial position of the support shaft with respect to the lower jacket. apparatus.