JP2006160242A - Telescopic steering device - Google Patents

Abstract

To simplify the structure of a telescopic steering device and to reduce the size and weight of the device.
A telescopic steering apparatus includes a steering column 20 that can be extended and contracted in a column axial direction, and the steering column 20 is provided with a support stiffness varying means St. The support stiffness varying means St is configured such that the support stiffness of the steering column 20 is determined by the column axial length Xa of the sliding contact portion between the outer column tube 21 and the inner column tube 22 (the thick portion S1 of the outer column tube 21). When the steering column 20 extends in the column axial direction from the set length La when the steering column 20 extends in the column axial direction, the support rigidity of the steering column 20 is made larger than the set value according to the extension amount. When contracting in the column axis direction from the set length La, the support rigidity of the steering column 20 is made smaller than the set value in accordance with the contraction amount.
[Selection] Figure 1

Description

  The present invention relates to a vehicle steering device, and more particularly to a telescopic steering device in which a steering column can be expanded and contracted in a column axial direction with respect to a set length.

  In this type of steering device, when the steering column extends in the column axial direction, the length of the cantilever from the steering wheel supported by the steering column to the mounting position of the steering column on the vehicle body increases. When the vibration frequency (resonance frequency) decreases and the steering column contracts in the column axis direction, the above-mentioned cantilever length decreases, and the natural frequency of the cowl steering system increases. Further, the conventional telescopic steering device employs a structure in which the support rigidity of the steering column decreases when the steering column extends in the column axis direction.

For this reason, in the conventional telescopic steering device, for example, as shown in Non-Patent Document 1 below, even if the steering column expands and contracts in the column axis direction, the change in the natural frequency of the cowl steering system is suppressed. Resonance change suppression means that can be used is adopted.
Japan Society for Invention and Innovation Open Technical Report No. 2003-502912

  In the resonance change suppressing means of the telescopic steering device described in Non-Patent Document 1, the movable mass provided on the steering column moves forward (attached to the vehicle body) as the steering column extends in the column axial direction. The movable mass provided on the steering column moves backward (to the steering wheel side) as the steering column contracts in the column axial direction.

  For this reason, as the steering column extends or contracts in the column axial direction, a drive mechanism that moves the movable mass forward or backward is required, which complicates the structure of the device and reduces the size of the device.・ There is a risk of obstructing weight reduction.

  The present invention has been made for the purpose of simplifying the structure of the apparatus and reducing the size and weight of the apparatus. Further, according to the present invention, in the telescopic type steering device in which the steering column can be extended and contracted in the column axis direction with respect to the set length, when the steering column extends in the column axis direction from the set length, the extension is made according to the extension amount. Support stiffness variable means for making the support stiffness of the steering column larger than a set value and for reducing the support stiffness of the steering column from a set value according to the amount of contraction when the steering column shrinks in the column axial direction from a set length. It is characterized by the provision.

  In this telescopic steering device, when the steering column extends in the column axis direction from the set length, the support stiffness varying means increases the support stiffness of the steering column from the set value in accordance with the extension amount of the steering column. For this reason, it is possible to suppress a decrease in the natural frequency of the cowl steering system as compared with the case where the support stiffness varying means is not provided.

  Further, when the steering column is contracted in the column axis direction from the set length, the support stiffness varying means makes the support stiffness of the steering column smaller than the set value according to the contraction amount of the steering column. For this reason, it is possible to suppress an increase in the natural frequency of the cowl steering system as compared with the case where the support stiffness varying means is not provided.

  Therefore, in this telescopic steering device, the variation range of the natural frequency of the cowl steering system when the steering column is changed from the maximum length to the minimum length is reduced as compared with the case where the support stiffness varying means is not provided. It is possible.

  Further, in this telescopic steering device, the support rigidity changing means changes the support rigidity of the steering column in accordance with the expansion / contraction amount of the steering column (for example, the sliding contact portion of the outer column tube and the inner column tube provided in the steering column) The steering column support rigidity is determined by the length in the column axial direction, or the steering column support rigidity depends on the contact area of the sliding contact portion of the outer column tube and the inner column tube provided in the steering column. In a steering column having a determined configuration or an outer column tube and an inner column tube, the inner column tube is slidably supported by being provided on the outer column tube. The support rigidity of the steering column is determined by the length in the column axial direction (support span at the steering column) between the outer side support and the inner side support that is provided on the inner column tube and slidably supports the outer column tube. It has a determined configuration) and does not require a drive mechanism in itself. For this reason, the structure of the device can be simplified, and the device can be reduced in size and weight.

  In the telescopic steering device described above, when the steering shaft that is rotatably supported by the steering column includes an outer shaft and an inner shaft that can be expanded and contracted in the column axial direction, the support stiffness varying means is provided on the outer shaft. Column axial length between the outer side support part that slidably supports the inner shaft and the inner side support part that is provided on the inner shaft and slidably supports the outer shaft (support span on the steering shaft) It is also possible to have a configuration in which the support rigidity of the steering column is determined by the above.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of a steering apparatus according to the present invention. In the steering apparatus according to the first embodiment, an upper shaft is capable of extending and contracting a steering shaft 10 in the column axis direction and transmitting torque. 11 and a lower shaft 12, and a steering column 20 that supports the steering shaft 10 rotatably and can extend and contract in the column axial direction includes an outer column tube 21 and an inner column tube 22. The outer column tube 21 is sometimes referred to as an upper column tube, and the inner column tube 22 is sometimes referred to as a lower column tube.

  The upper shaft 11 is supported so as to be rotatable and non-movable in the column axial direction with respect to the outer column tube 21 via a bearing Br1, and a steering wheel (not shown) can be integrally rotated at the upper end of the right end in FIG. It can be assembled. On the other hand, the lower shaft 12 is rotatably supported on the inner column tube 22 via a bearing Br2, and can be extended and contracted via a universal joint at the lower end at the left end of FIG. The intermediate shaft is connected to a steering gear box (both not shown) via a universal joint.

  The outer column tube 21 is slidably fitted and connected to the upper end of the inner column tube 22 at the lower end so as to be slidable and extendable. The outer column tube 21 is tilted by a column side bracket 21a fixed to the outer periphery of the lower end. And it is assembled | attached to the vehicle body side bracket 91 fixed to a part (illustration omitted) of the vehicle body via the upper support mechanism A in which telescopic adjustment is possible. On the other hand, the inner column tube 22 is assembled to a part (not shown) of the vehicle body in a tiltable manner via a lower support mechanism B that can be rotated by a bracket 22a fixed to the lower end portion.

  The upper support mechanism A allows the tilting of the steering column 20 to be permitted / restricted, and can adjust the tilting angle of a steering wheel (not shown) assembled to the upper shaft 11, and the column of the steering shaft 10 and the steering column 20. A telescopic mechanism that can permit and restrict axial expansion and contraction and can adjust the column axial position of a steering wheel (not shown) is integrally provided.

  As shown in FIG. 2, the upper support mechanism A includes a breakaway bracket 31 that is assembled to the vehicle body side bracket 91 so as to be movable and detachable forward. A column side bracket 21 a is attached to the breakaway bracket 31. Tightening bolt 32, thrust bearing 33, nut 34, cam plates 35, 36, operation lever 37, collar 38, eccentric cam 39, etc. that can be fixed / released (tilt adjustment and telescopic adjustment are possible in the released state) ing.

  The breakaway bracket 31 supports the column side bracket 21a so as to be tiltable in the vertical direction (tiltable) and movable in the column axis direction (telescopically possible). As shown in FIGS. It has a pair of left and right arms 31a and 31b, and has a pair of attachment portions 31c and 31d above the arms 31a and 31b, and the slit holes 31c1 and 31d1 provided in these attachment portions 31c and 31d. The mounting bolts 43 are used to assemble the vehicle body side bracket 91 via the resin capsules 41 and the metal collars 42. Each mounting bolt 43 is screwed and fixed to each weld nut 92 fixed to the vehicle body side bracket 91 in advance.

  The slit holes 31c1 and 31d1 of the breakaway bracket 31 enable the breakaway bracket 31 to move forward and away at the time of a secondary collision at the time of a vehicle collision. It extends to the end and opens at the rear end. Each resin capsule 41 has a cylindrical portion 41a that fits into each slit hole 31c1, 31d1, and is fixedly attached to the upper surface of each mounting portion 31c, 31d, and at a predetermined load during a secondary collision. It is going to be destroyed. Each metal collar 42 is press-fitted and fitted into the cylindrical portion 41a of each resin capsule 41, and in a state where the metal collar 42 is assembled to the vehicle body side bracket 91 using each mounting bolt 43, the resin capsule 41 is held in a secondary collision. Destructible.

  The tightening bolt 32 includes a pair of left and right arc-shaped insertion holes 31a1 and 31b1 provided in both arms 31a and 31b of the breakaway bracket 31, and a pair of left and right linear insertion holes 21a1 and 21a2 provided in the column side bracket 21a. Is inserted. The arc-shaped insertion holes 31a1 and 31b1 are arc-shaped tilt long holes centered on the rotation center of the lower support mechanism B shown in FIG. 1, and allow tilt adjustment. The linear insertion holes 21a1 and 21a2 are linear telescopic long holes formed along the column axis direction, and enable telescopic adjustment.

  The thrust bearing 33 is assembled to the bolt 32 between the arm 31b on the right side of the breakaway bracket 31 and the nut 34, and ensures integral rotation of the bolt 32 and the nut 34. The nut 34 is screwed and fixed to the screw portion 32 a of the bolt 32. The cam plates 35 and 36 and the operation lever 37 are assembled on the shaft portion 32 c of the bolt 32 between the left arm 31 a of the breakaway bracket 31 and the head portion 32 b of the bolt 32.

  The left cam plate 35 and the operation lever 37 are integrally connected and assembled on the shaft portion 32 c of the bolt 32, and can be rotated relative to the right cam plate 36. The right cam plate 36 is rotatable on the shaft portion 32c of the bolt 32 and is movable in the bolt axial direction, cannot rotate with respect to the linear insertion hole 21a1 of the column side bracket 21a, and is in the column axial direction. It is movable.

  The pair of left and right cam plates 35, 36 converts the rotation of the operating lever 37 into the axial movement of the bolt 32 and tightens the bolt 32 and the nut 34 (the bolt 32 between the head 32 b of the bolt 32 and the nut 34). The shaft portion 32c of the bolt 32 is in a pulled state) or a relaxed state (a state in which the shaft portion 32c of the bolt 32 is loosened between the head portion 32b of the bolt 32 and the nut 34). Therefore, the description thereof is omitted.

  The operating lever 37 is connected to the head portion 32b of the bolt 32 using a connecting plate 37a, and rotates integrally with the bolt 32. When the operation lever 37 is rotated so as to be lifted, the rotation of the operation lever 37 is converted into the axial movement of the bolt 32 by both the cam plates 35 and 36, the both cam plates 35 and 36 are separated, and the bolt As a result, the frictional force obtained between the brackets 21a and 31 is increased. As a result, the column side bracket 21a is fixed (locked) to the breakaway bracket 31 by frictional engagement, and the tilting and column axial movement of the steering column 20 are restricted.

  Further, when the operation lever 37 is rotated so as to be pushed down, the rotation of the operation lever 37 is converted into the axial movement of the bolt 32 by the both cam plates 35, 36, and both the cam plates 35, 36 come close to each other. 32 and the nut 34 are in a relaxed state, and the frictional force described above is reduced. Accordingly, the fixation of the column side bracket 21a by the frictional engagement with the breakaway bracket 31 is released, and the tilting of the steering column 20 and the column axial movement are permitted.

  The collar 38 is assembled on the shaft portion 32c of the bolt 32 in the column side bracket 21a so that it cannot rotate and cannot move in the direction of the bolt axis (integrally). It rotates integrally with the bolt 32. The eccentric cam 39 is integrally assembled with the collar 38, and can be engaged and separated from the lower surface of the upper end portion of the inner column tube 22 through an opening provided in the outer column tube 21, so that the operation lever 37 can be rotated. Accordingly, it rotates integrally with the bolt 32.

  The eccentric cam 39 is rotated so that the operation lever 37 is lifted, so that it rotates counterclockwise in FIG. 1 and engages with the lower surface of the upper end of the inner column tube 22 so that the inner column tube 22 is moved upward. The frictional force between the outer column tube 21 and the inner column tube 22 is increased by pushing up. Thereby, the inner column tube 22 is fixed (locked) to the outer column tube 21 by friction engagement, and the expansion and contraction of the steering column 20 in the column axial direction is restricted.

  Further, the eccentric cam 39 is rotated so that the operation lever 37 is pushed down, thereby rotating in the clockwise direction in FIG. 1 to be separated from the lower surface of the upper end portion of the inner column tube 22, thereby making the inner column tube 22 free. Reduce the frictional force described above. Thereby, the fixation of the inner column tube 22 with respect to the outer column tube 21 by the frictional engagement is released, and the expansion and contraction of the steering column 20 in the column axial direction is permitted.

  The lower support mechanism B supports the inner column tube 22 in the steering column 20 so that the inner column tube 22 can always be tilted (rotated), and is freely rotatable in a mounting hole 22a1 formed in a bracket 22a fixed to the lower end portion of the inner column tube 22. And a bolt and a nut (not shown) for fixing the collar 51 to a part of the vehicle body (not shown).

  By the way, in the first embodiment, as shown in FIG. 1, the lower end portion of the outer column tube 21 is partially thickened, and the inner diameter of the thick portion S1 is smaller than the inner diameter of the thin portion. The diameter is small. Further, the upper end portion of the inner column tube 22 is partially thickened, and the outer diameter of the thick portion S2 is larger than the outer diameter of the thin portion, and the thick portion S1 of the outer column tube 21. The inner diameter is substantially the same.

  The thick part S1 at the lower end of the outer column tube 21 and the thick part S2 at the upper end of the inner column tube 22 constitute the support stiffness varying means St according to the present invention. The column axial length L1 of S1 is substantially equal to the column axial length L2 of the thick portion S2 of the inner column tube 22.

  When the steering column 20 extends in the column axis direction as shown in FIG. 3 from the set length La shown in FIG. 1, the support stiffness varying means St supports the steering column 20 according to the extension amount (Lb−La). When the rigidity is made larger than the set value in the state of FIG. 1 and the steering column 20 is contracted in the column axial direction as shown in FIG. 4 from the set length La, the steering column is in accordance with the contraction amount (La-Lc). The support rigidity of 20 is made smaller than the set value.

  Further, the support stiffness varying means St is determined by the length in the column axial direction of the sliding contact portion between the outer column tube 21 and the inner column tube 22 (see Xa in FIG. 1, Xb in FIG. 3, and Xc in FIG. 4). The support rigidity is determined, and the contact area of the sliding contact portion between the outer column tube 21 and the inner column tube 22 (Xa, Xb or Xc described above, the outer column tube 21 and the inner column tube shown in FIG. 2). The support rigidity of the steering column 20 is determined by the product of the circumferential lengths of the 22 sliding contact portions).

  In the steering apparatus of the first embodiment configured as described above, when the steering column 20 extends in the column axial direction as shown in FIG. 3 from the set length La shown in FIG. However, the support rigidity of the steering column 20 is made larger than the set value in the state of FIG. 1 according to the extension amount (Lb−La) of the steering column 20. For this reason, it is possible to suppress a decrease in the natural frequency of the cowl steering system as compared with the case where the support stiffness varying means St is not provided.

  Further, when the steering column 20 is contracted in the column axial direction as shown in FIG. 4 from the set length La shown in FIG. 1, the support stiffness varying means St depends on the contraction amount (La−Lc) of the steering column 20. The support rigidity of the steering column 20 is made smaller than the set value in the state of FIG. For this reason, it is possible to suppress an increase in the natural frequency of the cowl steering system as compared with the case where the support stiffness varying means St is not provided.

  Therefore, in this telescopic steering device, the change in the natural frequency of the cowl steering system when the steering column 20 is changed from the maximum length Lb to the minimum length Lc, as compared with the case where the support stiffness varying means St is not provided. It is possible to reduce the width.

  Further, in this telescopic steering device, the support stiffness variable means St changes the support stiffness of the steering column 20 according to the amount of expansion and contraction of the steering column 20 (the outer column tube 21 and the inner column tube 22 provided in the steering column 20). The support rigidity of the steering column 20 is determined by the length of the sliding contact portion in the column axial direction, or the contact of the sliding contact portion between the outer column tube 21 and the inner column tube 22 provided in the steering column 20 It has a configuration in which the support rigidity of the steering column 20 is determined by the area), and does not require a drive mechanism in itself. For this reason, the structure of the device can be simplified, and the device can be reduced in size and weight.

  In the first embodiment, the thick portion S1 is integrally formed on the outer column tube 21 and the thick portion S2 is integrally formed on the inner column tube 22, but this is shown in FIGS. As in the modified embodiment, the thick portion 23 formed separately from the outer column tube 21 is integrally assembled to the inner periphery of the outer column tube 21 to form the thick portion S1, and FIGS. As shown in FIG. 7, it is possible to form the thick portion S2 by integrally assembling the thick forming member 24 formed separately from the inner column tube 22 on the outer periphery of the inner column tube 22. The thick forming member 23 is integrally formed with a protrusion 23 a on the outer periphery of the intermediate portion for assembling the thick forming member 23 integrally with the outer column tube 21. Further, the thick forming member 24 is integrally formed with a protrusion 24 a for assembling the thick forming member 24 integrally with the inner column tube 22 on the inner periphery of the intermediate portion.

  In the first embodiment, the column shaft of the sliding contact portion (the portion that changes as the steering column 20 extends and contracts in the column axis direction) between the outer column tube 21 and the inner column tube 22 provided in the steering column 20. Although the configuration in which the support rigidity of the steering column 20 is determined by the length in the direction and the contact area is adopted, the frictional engagement force of the sliding contact portion of the outer column tube 21 and the inner column tube 22 provided in the steering column 20 is steering. It can also be configured and implemented so as to increase or decrease as the column 20 expands and contracts in the direction of the column axis.

  9 to 12 show a second embodiment of the steering apparatus according to the present invention. In the steering apparatus according to the second embodiment, a resin-made assembly is integrally assembled to the lower inner periphery of the outer column tube 21. FIG. The outer-side support bush 25 and the resin-made inner-side support bush 26 integrally assembled to the outer periphery of the upper portion of the inner column tube 22 constitute the support stiffness varying means St according to the present invention. The outer side support bush 25 is formed in an annular shape with a predetermined width, and is fixed to the outer column tube 21 by a protrusion 25a provided on the outer periphery.

  When the steering column 20 extends in the column axis direction from the set length, the support stiffness varying means St is configured to support span (the length in the column axis direction between the outer side support bush 25 and the inner side support bush 26 in accordance with the extension amount). When the steering column 20 contracts in the column axial direction from the set length, the support span is shortened according to the contraction amount, and the steering column 20 The support rigidity of 20 is made smaller than the set value.

  Further, the support stiffness varying means St is provided on the outer column tube 21 and slidably supports the inner column tube 22 and the outer column support bush 25 and the inner column tube 22 are slidable on the outer column tube 21. The support rigidity of the steering column 20 is determined by the length in the column axial direction (support span in the steering column 20) between the inner support bush 26 and the inner side support bush 26.

  In the first embodiment and the second embodiment described above, the steering column 20 is provided with the support stiffness variable means St that changes the support stiffness of the steering column 20 as the steering column 20 extends and contracts in the column axis direction. Although implemented, the supporting stiffness varying means is the same as that of the third embodiment shown in FIGS. 13 to 16, the fourth embodiment shown in FIGS. 17 to 20, or the fifth embodiment shown in FIGS. As described above, the present invention can be carried out by providing the steering shaft (between the upper shaft and the lower shaft capable of extending and contracting in the column axis direction and transmitting torque).

  In the steering apparatus according to the third embodiment shown in FIGS. 13 to 16, the lower shaft 12 is formed integrally with the lower inner periphery of the upper shaft 11, that is, the inner periphery of the outer shaft portion formed in a cylindrical shape. 3 outer fittings that are slidable in the column axis direction and capable of transmitting torque to engagement grooves 12a extending in the column axis direction formed on the outer periphery of the upper end portion of the inner shaft portion, that is, the outer periphery of the cylindrical inner shaft portion. Side support protrusions 11a and the upper outer periphery of the lower shaft 12, that is, the outer periphery of the lower shaft portion of the upper shaft 11 formed integrally with the outer periphery of the inner shaft portion formed in a columnar shape, that is, the outer shape formed in a cylindrical shape Three inner fittings that are slidable in the column axis direction and capable of transmitting torque in engagement grooves 11b formed in the inner periphery of the shaft portion and extending in the column axis direction By the side support protrusions 12b, the support rigidity changing means Ss according to the present invention is constituted.

  When the steering column 20 extends in the column axial direction from the set length, the support stiffness varying means Ss is configured so that the support span of the steering shaft 10 (between the outer side support projection 11a and the inner side support projection 12b) according to the extension amount. When the steering column 20 contracts in the column axial direction from the set length, the support of the steering shaft 10 is supported according to the contraction amount. The span is shortened to make the support rigidity of the steering column 20 smaller than a set value.

  Further, the support stiffness varying means Ss is provided on the outer shaft portion of the upper shaft 11 to support the lower shaft 12 slidably and the inner shaft portion of the lower shaft 12 to be supported on the upper shaft 11. The support rigidity of the steering column 20 is determined by the length in the column axial direction (support span in the steering shaft 10) between the inner support protrusion 12b and the inner side support protrusion 12b.

  In the steering device of the fourth embodiment shown in FIGS. 17 to 20, the upper end of the lower shaft 12 is assembled to the lower inner periphery of the upper shaft 11, that is, the inner periphery of the outer shaft portion formed in a cylindrical shape. Three outer side supports that are slidable in the column axis direction and capable of transmitting torque to engaging grooves 12a extending in the column axis direction formed on the outer periphery of the inner part, that is, the outer periphery of the cylindrical inner shaft part A pin (which can be implemented by a ball instead of a pin) 13 and an upper outer periphery of the lower shaft 12, that is, an outer periphery of an inner shaft portion formed in a columnar shape, are integrally formed within the lower end portion of the upper shaft 11 Slidable in the column axial direction in the engagement groove 11b extending in the column axial direction formed on the circumference, that is, on the inner circumference of the outer shaft portion formed in a cylindrical shape. The support stiffness variable according to the present invention is achieved by three inner side support pins 14 that are fitted so as to be able to transmit the clutch, and a spring 15 that is interposed between the outer side support pin 13 and the inner side support pin 14 and biases them apart. Means Ss is configured.

  When the steering column 20 extends in the column axial direction from the set length, the support stiffness varying means Ss is configured so that the support span of the steering shaft 10 (between the outer side support pin 13 and the inner side support pin 14 depends on the extension amount). When the steering column 20 contracts in the column axial direction from the set length, the support of the steering shaft 10 is supported according to the contraction amount. The span is shortened to make the support rigidity of the steering column 20 smaller than a set value.

  Further, the support stiffness varying means Ss is provided on the outer shaft portion of the upper shaft 11 and is provided on the outer side support pin 13 that slidably supports the lower shaft 12 and the inner shaft portion of the lower shaft 12. The support rigidity of the steering column 20 is determined by the length in the column axial direction (support span in the steering shaft 10) between the inner support pin 14 and the inner side support pin 14 that slidably supports the steering column 20. In this support stiffness varying means Ss, since the spring 15 is employed, it is possible to reduce the machining accuracy of the shafts 11 and 12, and to reduce the cost.

  In the steering apparatus according to the fifth embodiment shown in FIGS. 21 to 24, an elastic body (rubber spacer) for backlashing is provided on the lower inner circumference of the upper shaft 11, that is, on the inner circumference of the cylindrical outer shaft portion. ) 16 and a pin fixing member (C ring) 17, and an engagement groove extending in the column axis direction formed on the outer periphery of the upper end portion of the lower shaft 12, that is, on the outer periphery of the inner shaft portion formed in a columnar shape. Three outer support pins 13 fitted to 12a so as to be slidable in the column axis direction and capable of transmitting torque, and the outer periphery of the upper portion of the lower shaft 12, that is, the outer periphery of the inner shaft portion formed in a columnar shape Is assembled using an elastic body (rubber spacer) 18 and a pin fixing member (C ring) 19 to form the inner periphery of the lower end of the upper shaft 11, that is, in a cylindrical shape. A support according to the present invention is provided by three inner side support pins 14 which are slidable in the column axis direction and capable of transmitting torque in engagement grooves 11b formed in the inner circumference of the outer shaft portion and extending in the column axis direction. The stiffness variable means Ss is configured.

  When the steering column 20 extends in the column axial direction from the set length, the support stiffness varying means Ss is configured so that the support span of the steering shaft 10 (between the outer side support pin 13 and the inner side support pin 14 depends on the extension amount). When the steering column 20 contracts in the column axial direction from the set length, the support of the steering shaft 10 is supported according to the contraction amount. The span is shortened to make the support rigidity of the steering column 20 smaller than a set value.

  Further, the support stiffness varying means Ss is provided on the outer shaft portion of the upper shaft 11 and is provided on the outer side support pin 13 that slidably supports the lower shaft 12 and the inner shaft portion of the lower shaft 12. The support rigidity of the steering column 20 is determined by the length in the column axial direction (support span in the steering shaft 10) between the inner support pin 14 and the inner side support pin 14 that slidably supports the steering column 20.

  In the third to fifth embodiments described above, it is possible to stabilize the support rigidity of the steering column 20, and when the steering column 20 extends and contracts in the column axial direction, the upper shaft 11 and the lower The fitting length of the shaft 12 changes, the torsional rigidity of the steering shaft 10 also changes, and this torsional rigidity can be stabilized. Note that the torsional rigidity of the steering shaft 10 affects the steering feeling, particularly the feeling at the start of steering.

It is a vertical side view which shows 1st Embodiment of the steering device by this invention. It is a longitudinal front view which shows the structure of the upper support mechanism in the steering apparatus shown in FIG. FIG. 2 is a longitudinal side view of a state in which a steering column of the steering apparatus shown in FIG. 1 is extended from a set length in a column axial direction. FIG. 2 is a longitudinal side view of a state in which the steering column of the steering apparatus shown in FIG. 1 is contracted in a column axial direction from a set length. It is a vertical side view which shows roughly the deformation | transformation embodiment formed in the thick part formed separately from the outer column tube in the thick part of the outer column tube shown in FIG. It is a perspective view of the thick formation member shown in FIG. It is a vertical side view which shows roughly the deformation | transformation embodiment formed in the thick formation member formed separately from the inner column tube in the thick part of the inner column tube shown in FIG. It is a perspective view of the thick formation member shown in FIG. It is a principal part vertical side view which shows 2nd Embodiment of the steering device by this invention. FIG. 10 is a longitudinal front view of the outer side support portion of the steering device shown in FIG. 9. FIG. 10 is a longitudinal front view of an inner side support portion of the steering device shown in FIG. 9. FIG. 10 is a longitudinal side view of the steering device shown in FIG. 9 in a state in which the steering column is contracted in the column axis direction. It is a principal part vertical side view which shows 3rd Embodiment of the steering device by this invention. It is a vertical front view in the outer side support part of the steering device shown in FIG. It is a vertical front view in the inner side support part of the steering device shown in FIG. FIG. 14 is a longitudinal side view of a state in which the steering column of the steering apparatus shown in FIG. 13 is contracted in the column axial direction. It is a principal part vertical side view which shows 4th Embodiment of the steering device by this invention. It is a vertical front view in the outer side support part of the steering device shown in FIG. It is a longitudinal front view in the inner side support part of the steering device shown in FIG. FIG. 18 is a longitudinal side view of a state in which the steering column of the steering apparatus shown in FIG. 17 is contracted in the column axis direction. It is a principal part vertical side view which shows 5th Embodiment of the steering device by this invention. FIG. 22 is a longitudinal front view of the outer support portion of the steering device shown in FIG. 21. It is a longitudinal front view in the inner side support part of the steering device shown in FIG. FIG. 22 is a longitudinal side view of the steering device shown in FIG. 21 with the steering column contracted in the column axis direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Steering shaft, 11 ... Upper shaft, 12 ... Lower shaft, Br1 ... Bearing, Br2 ... Bearing, 20 ... Steering column, 21 ... Outer column tube, 22 ... Inner column tube, St ... Support rigidity variable means, S1 ... Outer Thick part of column tube, S2 ... Thick part of inner column tube, La ... Steering column setting length, Lb ... Maximum length of steering column, Lc ... Minimum length of steering column, Xa, Xb, Xc ... Outer column tube Column axial length of sliding part of inner column tube

Claims (5)

  In a telescopic steering device in which the steering column can extend and contract in the column axis direction with respect to the set length, when the steering column extends in the column axis direction from the set length, the support rigidity of the steering column according to the extension amount When the steering column is contracted in the column axial direction from the set length, a support stiffness variable means is provided for reducing the support stiffness of the steering column below the set value according to the amount of contraction. Telescopic steering device.   2. The telescopic steering apparatus according to claim 1, wherein the steering column includes an outer column tube and an inner column tube that are slidable and extendable in a column axial direction, and the support stiffness varying means is the outer column tube. And a structure in which the support rigidity of the steering column is determined by the length in the column axial direction of the sliding contact portion of the inner column tube.   2. The telescopic steering apparatus according to claim 1, wherein the steering column includes an outer column tube and an inner column tube that are slidable and extendable in a column axial direction, and the support stiffness varying means is the outer column tube. A telescopic steering device characterized in that the support rigidity of the steering column is determined by the contact area of the sliding contact portion of the inner column tube.   2. The telescopic steering device according to claim 1, wherein the steering column includes an outer column tube and an inner column tube that can be expanded and contracted in a column axial direction, and the support stiffness varying means is provided on the outer column tube. The column axial length between the outer side support portion that slidably supports the inner column tube and the inner side support portion that is provided on the inner column tube and slidably supports the outer column tube A telescopic steering device, characterized in that the support rigidity of the steering column is determined. 2. The telescopic steering device according to claim 1, wherein a steering shaft rotatably supported by the steering column includes an outer shaft and an inner shaft that can expand and contract in a column axial direction, Column axial length between an outer side support part provided on the outer shaft and slidably supporting the inner shaft and an inner side support part provided on the inner shaft and slidably supported by the outer shaft A telescopic steering device characterized in that the support rigidity of the steering column is determined by the height.

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