JP2014223855A - Steering column device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering column device which improves the operability of an operation lever in a structure in which an inner tube is pressed against an outer tube in conjunction with the operation of the operation lever.SOLUTION: A steering column device 1 includes: an inner tube 32; an outer tube 31; a rotation shaft 6; and a pressing member 42. The rotation shaft 6 rotates around an axis in response to the operation of an operation lever 7. The pressing member 42 moves between a pressing position, in which the pressing member 42 contacts with an outer peripheral surface 32C of the inner tube 32 to press the inner tube 32 against an inner peripheral surface 31C of the outer tube 31, and a release position, in which the pressing of the inner tube 32 against the outer tube 31 is released, in conjunction with rotations of the rotation shaft 6. A friction reduction material 100 which reduces friction between the inner tube 32 and the pressing member 42 is provided in at least one of the inner tube 32 and the pressing member 42.

Description

  The present invention relates to a steering column device.

  The steering column device disclosed in Patent Document 1 below includes an outer tube and an inner tube that are fitted so as to be relatively slidable in the axial direction. In addition, the steering column device includes a clamp bolt that passes through an upper clamp fixed to the vehicle body and a distance bracket fixed to the outer tube by welding or the like, and an operation lever that is rotated around the axis of the bolt. , And a cam body that rotates as the operating lever rotates. The upper clamp and the distance bracket are clamped between the head of the bolt and the nut (attached to the tip of the bolt) so that they cannot be moved relative to each other by tightening the bolt by rotating the operation lever. Can do. Simultaneously with the clamping here, the cam body enters the outer tube through the through hole of the outer tube and presses against the inner tube, thereby pressing the inner tube against the inner peripheral surface of the outer tube. The backlash is removed.

JP 2010-30579 A

  In the case of Patent Document 1, the cam body presses the inner tube against the outer tube while contacting the inner tube in conjunction with the operation of the operation lever. In this case, when the cam body presses the inner tube against the outer tube, friction is generated between the cam body and the inner tube. If the friction between the cam body and the inner tube is large, the force required to operate the operation lever (operation force) and the operation amount of the operation lever (operation angle when the operation lever is rotated) It becomes larger than the value originally required to press against the tube. This may reduce the operability of the operation lever.

  The present invention has been made based on such a background, and provides a steering column device capable of improving the operability of the operation lever in a configuration in which the inner tube is pressed against the outer tube in conjunction with the operation of the operation lever. The purpose is to do.

  According to the first aspect of the present invention, an inner tube (32) into which a steering shaft (2) to which a steering member (8) is connected is inserted, and an outer tube (31) externally fitted to the inner tube. The inner tube and the outer tube extend in a direction (Y) intersecting with the column tube (3) movable relative to the axial direction (X) of the steering shaft, A rotating shaft (6) to which a lever (7) is attached, the rotating shaft rotating around the shaft in accordance with the operation of the operating lever, and the inner tube contacting with the outer peripheral surface (32C) of the inner tube Is pressed against the inner peripheral surface (31C) of the outer tube, and the release position is to release the inner tube from being pressed against the outer tube. Between the pressing member (42) movable in conjunction with the rotation of the rotating shaft and at least one of the inner tube and the pressing member, and the friction between the inner tube and the pressing member is reduced. It is a steering column apparatus (1) characterized by including the friction reduction material (100) to reduce.

The invention according to claim 2 is characterized in that the friction reducing material is applied to at least one of the outer peripheral surface of the inner tube and the surface (44A, 45A) of the pressing member. The steering column device according to claim 3, wherein at least one of the inner tube and the pressing member is made of the friction reducing material. .

According to a fourth aspect of the present invention, the pressing member is connected to the rotating shaft and is eccentrically rotated in conjunction with the rotation of the rotating shaft to move between the pressing position and the release position. (44) It is a steering column apparatus in any one of Claims 1-3 characterized by the above-mentioned.
The invention according to claim 5 includes an eccentric cam that is coupled to the rotary shaft and rotates eccentrically in conjunction with the rotation of the rotary shaft, and the pressing member is a ring (45) that is externally fitted to the eccentric cam. And a ring that is movable between the pressing position and the release position in response to the eccentric cam rotating eccentrically in conjunction with rotation of the rotating shaft. It is a steering column apparatus in any one of 1-3.

The invention according to claim 6 is the steering column device according to any one of claims 1 to 5, wherein the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube are spline-fitted. It is.
In addition, in the above, the numbers in parentheses represent reference numerals of corresponding components in the embodiments described later, but the scope of the claims is not limited by these reference numerals.

  According to the first aspect of the present invention, in the steering column device, the outer tube is externally fitted to the inner tube, and the pressing member rotates the rotation shaft (that is, operates the operation lever attached to the rotation shaft). ) And move to the pressing position, abut against the outer peripheral surface of the inner tube and press the inner tube against the inner peripheral surface of the outer tube. Thereby, an inner tube and an outer tube are locked so that relative movement is impossible.

  Here, the friction reducing material provided on at least one of the inner tube and the pressing member reduces the friction between the inner tube and the pressing member, so that the influence of the friction on the operation of the operation lever can be reduced. . Thereby, the operating force of the operating lever required to press the inner tube against the inner peripheral surface of the outer tube can be kept low. Further, the inner tube can be pressed against the inner peripheral surface of the outer tube even when the operation amount of the operation lever is small compared to the case where the friction reducing material is not provided.

As a result, in the configuration in which the inner tube is pressed against the outer tube in conjunction with the operation of the operation lever, the operability of the operation lever can be improved.
If at least the inner tube is provided with a friction reducing material, in addition to the friction between the inner tube and the pressing member, the friction between the inner tube and the outer tube is also reduced. Therefore, it is possible to reduce a force (telescopic operation force) required when the inner tube and the outer tube relatively move (telescopic movement) in the axial direction of the steering shaft. Furthermore, in the so-called EA (Energy Absorption) load and separation load in the secondary collision, the ratio (contribution rate) contributed by the friction between the inner tube and the outer tube can be reduced by the friction reducing material. It is possible to suppress variations in the EA load and the separation load due to friction.

  According to the second aspect of the present invention, the friction reducing material is applied to at least one of the outer peripheral surface of the inner tube and the surface of the pressing member without considering the friction coefficient in the respective materials of the inner tube and the pressing member. The friction between the inner tube and the pressing member can be reduced. That is, the choice of each material of an inner tube and a pressing member can be increased.

According to the invention of claim 3, since at least one of the inner tube and the pressing member is made of the friction reducing material, it is not necessary to provide the friction reducing material in post-processing.
As in the invention described in claim 4, the pressing member may be an eccentric cam.
As in the fifth aspect of the invention, the pressing member may be a ring externally fitted to an eccentric cam connected to the rotating shaft.

  According to the sixth aspect of the invention, even if the friction reducing material is provided on the outer peripheral surface of the inner tube, the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube are spline-fitted. It is possible to prevent the tube and the outer tube from relatively rotating in the circumferential direction.

FIG. 1 is a schematic diagram showing a schematic configuration of a steering column apparatus 1 according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of the steering column device 1 taken along line II-II in FIG. FIG. 3A is a cross-sectional view of the main part of the steering column device 1 cut along the axial direction X, and shows a state in which the pressing member 42 is in the pressing position, and FIG. These show the state after the pressing member 42 has moved to the release position from the state of FIG. FIG. 4 is a diagram in which a modification is applied to FIG. 2, and shows a case where the outer peripheral surface 32C of the inner tube 32 and the inner peripheral surface 31C of the outer tube 31 are spline-fitted.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of a steering column apparatus 1 according to an embodiment of the present invention. Here, in FIG. 1, the left side of the page is the front side of the vehicle body 14, the right side of the page is the rear side of the vehicle body 14, the upper side of the page is the upper side of the vehicle body 14, and the lower side of the page is the lower side of the vehicle body 14. A direction in which the central axis of the steering shaft 2 extends (a direction close to the front-rear direction) is defined as an axial direction X. 1 is the left-right direction Y, and the direction perpendicular to the axial direction X extends along the line II-II (the direction close to the vertical direction). ) Is an orthogonal direction Z.

  Referring to FIG. 1, a steering column device 1 includes a steering shaft 2, a column tube 3 having an outer tube 31 and an inner tube 32, an upper column bracket 4, an upper fixing bracket 5, a lower fixing bracket 17, The rotating shaft 6 and the pressing member 42 are mainly included. The steering column device 1 is attached to the vehicle body 14 by an upper fixing bracket 5 and a lower fixing bracket 17. The function of the steering column device 1 will be described briefly. The steering shaft 2 rotates around its central axis by the steering torque transmitted from the steering member 8 such as a steering wheel. This rotation is transmitted to the steering mechanism 13 such as a rack and pinion mechanism via the first universal joint 9, the intermediate shaft 10, the second universal joint 11 and the pinion shaft 12 included in the steering column device 1. Thereby, steered wheels such as tires (not shown) connected to the steering mechanism 13 are steered.

  As will be described in detail later, when the driver rotates the rotating shaft 6 according to the operation of the operating lever 7 connected to the rotating shaft 6, the upper column bracket 4 connected to the column tube 3 is fixed to the upper portion. Fastened by the bracket 5. At the same time, the pressing member 42 presses the inner tube 32 of the column tube 3 against the outer tube 31. Thereby, the inner tube 32 and the outer tube 31 are fixed so that relative movement cannot be performed.

  Further, by operating the operation lever 7 in the direction opposite to the direction in which the column tube 3 is tightened and rotating the rotating shaft 6, the tightening of the upper column bracket 4 connected to the column tube 3 can be released. At the same time, the pressing member 42 releases the pressing of the inner tube 32 against the outer tube 31. Thus, the driver can perform so-called telescopic adjustment (adjustment of the expansion / contraction amount of the steering shaft 2 and the column tube 3) and tilt adjustment (adjustment of the inclination of the steering shaft 2 and the column tube 3).

  FIG. 2 is a schematic cross-sectional view of the steering column device 1 taken along line II-II in FIG. Here, the direction orthogonal to the paper surface in FIG. 2 coincides with the axial direction X in FIG. Further, the vertical direction in FIG. 2 coincides with the orthogonal direction Z in FIG. Further, the left-right direction in FIG. 2 coincides with the left-right direction Y in FIG. 2 is the steering member 8 side (rear side of the vehicle body 14). 2 is the steering mechanism 13 side (the front side of the vehicle body 14).

In the following, description will be made with reference to FIG. 2 in addition to FIG.
First, referring to FIG. 1, the entire steering shaft 2 is a cylindrical body that extends obliquely toward the rear upper side of the vehicle body 14 (extends in the axial direction X). The steering shaft 2 includes a cylindrical upper shaft 21 and a cylindrical or columnar lower shaft 22. The upper shaft 21 is disposed behind the lower shaft 22. The upper shaft 21 and the lower shaft 22 are arranged coaxially.

  The above-described steering member 8 is connected to a rear end portion (which is also an upper end portion, but here referred to as a rear end portion) 21A of the upper shaft 21 (steering shaft 2). A part (rear end portion 22A) of the lower shaft 22 is inserted into the front end portion 21B of the upper shaft 21 from the front side. Referring also to FIG. 2, in a region where the lower shaft 22 is inserted into the upper shaft 21 (region where the front end portion 21B of the upper shaft 21 and the rear end portion 22A of the lower shaft 22 overlap in the axial direction X), The upper shaft 21 and the lower shaft 22 are fitted to each other by spline fitting or serration fitting. Therefore, the upper shaft 21 and the lower shaft 22 are relatively movable along the axial direction X. Thereby, the steering shaft 2 can expand and contract along the axial direction X. Referring to FIG. 1, the rear end portion of the intermediate shaft 10 is connected to the front end portion 22 </ b> B of the lower shaft 22 via the first universal joint 9.

Further, the front end portion of the intermediate shaft 10 is connected to the pinion shaft 12 via the second universal joint 11. Therefore, the steering shaft 2 can finally transmit the steering torque transmitted from the steering member 8 to the steering mechanism 13 connected to the pinion shaft 12.
The entire column tube 3 is a hollow body that extends obliquely toward the rear upper side of the vehicle body 14 (extends in the axial direction X). A steering shaft 2 is inserted into the column tube 3 (hollow portion of the column tube 3). The column tube 3 is arranged coaxially with the steering shaft 2. The column tube 3 includes an outer tube 31 and an inner tube 32. The outer tube 31 is disposed behind the inner tube 32. Further, the outer tube 31 and the inner tube 32 are arranged coaxially. The steering shaft 2 is inserted into the inner tube 32.

  The outer tube 31 and the inner tube 32 are substantially cylindrical when viewed from the axial direction X (see also FIG. 2). Here, in the outer tube 31, the rear end portion is marked with “A”, the front end portion is marked with “B”, the inner peripheral surface is marked with “C”, and the outer peripheral surface is marked with “C”. The symbol “D” is attached. On the other hand, in the inner tube 32, the rear end portion is denoted by “A”, the front end portion is denoted by “B”, and the outer peripheral surface is denoted by “C”.

  The outer tube 31 is externally fitted to the inner tube 32. Specifically, the rear end portion 32A of the inner tube 32 is inserted into the front end portion 31B of the outer tube 31 from the front side. Outer surface of the inner tube 32 in a region where the inner tube 32 is inserted in the outer tube 31 (a region where the front end portion 31B of the outer tube 31 and the rear end portion 32A of the inner tube 32 overlap in the axial direction X). There is a certain gap between 32C and the inner peripheral surface 31C of the outer tube 31. Therefore, the outer tube 31 and the inner tube 32 are relatively movable along the axial direction X. Thereby, the column tube 3 can expand and contract along the axial direction X.

  The outer tube 31 and the upper shaft 21 are connected via the first bearing 15. Further, the inner tube 32 and the lower shaft 22 are connected via the second bearing 16. Therefore, the outer tube 31 and the upper shaft 21, and the inner tube 32 and the lower shaft 22 are relatively movable in the axial direction X. Thereby, the column tube 3 and the steering shaft 2 can expand and contract at a time. The inner tube 32 is fixed to the lower column bracket 17A. The lower column bracket 17A is rotatably supported by a lower fixing bracket 17 fixed to the vehicle body 14 via a tilt center shaft 17B.

  Referring to FIG. 2, the upper column bracket 4 supports the column tube 3 (particularly, the outer tube 31) and connects the steering column device 1 to the vehicle body 14. The upper column bracket 4 is a groove-shaped member (substantially U-shaped when viewed from the axial direction X) that opens upward, and is formed symmetrically. More specifically, the upper column bracket 4 includes a pair of side plates (the right side plate 18 and the left side plate 19) opposed to each other, and a connecting plate 20 connecting the lower end portions of the pair of side plates (the right side plate 18 and the left side plate 19). It has. The upper ends (18A, 19A) of the pair of side plates are connected to the outer peripheral surface 31D of the outer tube 31 by welding or the like.

  The upper fixing bracket 5 supports the column tube 3 (particularly, the outer tube 31) via the upper column bracket 4 and connects the steering column device 1 to the vehicle body 14. The upper fixing bracket 5 is a member having a groove shape (substantially U-shaped upside down when viewed from the axial direction X) as a whole that opens downward, and is formed symmetrically. Specifically, the upper fixing bracket 5 includes a pair of opposing side plates (right side plate 23, left side plate 24) and a connecting plate 25 that connects upper end portions of the pair of side plates (right side plate 23, left side plate 24), It includes a plate-like mounting stay 26 that is fixed to the upper surface of the connecting plate 25 and extends substantially in the left-right direction Y.

The steering shaft 2, the column tube 3, and the upper column bracket 4 are disposed between a pair of side plates (between the right side plate 23 and the left side plate 24) of the upper fixing bracket 5 in FIG. Further, the upper fixing bracket 5 is fixed to the vehicle body 14 via a pair of mounting bodies 27 connected to the mounting stay 26.
Each attachment body 27 and the attachment stay 26 are connected by a breakable synthetic resin pin 28 that penetrates the attachment stay 26 in the vertical direction (orthogonal direction Z). It is being fixed to the vehicle body 14 by.

  In a so-called secondary collision, each pin 28 breaks, and the mounting stay 26 and the upper fixing bracket 5 are detached from the vehicle body 14. As a result, the outer tube 31 can move relative to the inner tube 32 in the front direction in the axial direction X. By this relative movement, absorption of impact (EA) of the secondary collision is achieved. Note that a load necessary for detaching the mounting stay 26 and the upper fixing bracket 5 from the vehicle body 14 is referred to as a “detachment load”, and a load absorbed after the separation is referred to as an “EA load”.

  The outer side surface (right side surface) of the corresponding right side plate 18 of the upper column bracket 4 is along the inner side surface (left side surface) of the right side plate 23 of the upper fixing bracket 5. Further, the outer side surface (left side surface) of the corresponding left side plate 19 of the upper column bracket 4 extends along the inner side surface (right side surface) of the left side plate 24 of the upper fixing bracket 5. Each of the right side plate 18 and the left side plate 19 of the upper column bracket 4 (strictly speaking, a position below the outer tube 31) is formed with a telescopic horizontal hole 33 extending in the axial direction X. In the right side plate 23 and the left side plate 24 of the upper fixing bracket 5, a vertically elongated hole 34 for tilting is formed.

The rotating shaft 6 is a cylindrical body that extends in a direction (left-right direction Y) intersecting the axial direction X of the steering shaft 2. A thread groove 6 </ b> C is formed on the outer peripheral surface 6 </ b> B at the right end 6 </ b> A of the rotating shaft 6. Further, a head 6E having a larger diameter than the main body of the rotating shaft 6 is formed at the left end 6D of the rotating shaft 6.
The rotary shaft 6 is inserted through a horizontally elongated hole 33 formed in each of the right side plate 18 and the left side plate 19 in the upper column bracket 4. Further, the rotating shaft 6 is also inserted into a vertically long hole 34 formed in each of the right side plate 23 and the left side plate 24 in the upper fixing bracket 5. Further, the rotating shaft 6 is disposed between the right side plate 18 and the left side plate 19 in a portion where the inner tube 32 is inserted in the outer tube 31 (the front end portion 31B of the outer tube 31 and the rear end of the inner tube 32 in the axial direction X). The region where the end portion 32A overlaps is disposed away from the lower portion.

A nut 35 that is screwed into the thread groove 6 </ b> C is provided on the right end 6 </ b> A of the rotating shaft 6. An annular cam 36 and an annular cam follower 37 are provided between the head 6 E and the left side plate 24 of the upper fixing bracket 5 at the left end 6 D of the rotating shaft 6.
The cam 36 has a first portion 36A that comes into contact with the head 6E from the right side, and a second portion 36B that is located on the right side of the first portion 36A and has a larger diameter than the first portion 36A. Here, an operation lever 7 is attached to the rotary shaft 6. Specifically, the operation lever 7 surrounds the outer peripheral surface of the first portion 36A, and is fixed in a state of being in contact with the right side surface of the head 6E and the left side surface of the second portion 36B. Therefore, the operation lever 7 can rotate the rotation shaft 6 and the cam 36 around the rotation shaft 6 in accordance with the operation of the operation lever 7.

  The cam follower 37 has a first portion 37A and a second portion 37B. The first portion 37 </ b> A of the cam follower 37 extends along the outer side surface (left side surface) of the left side plate 24 of the upper fixing bracket 5. The second portion 37 </ b> B of the cam follower 37 extends along the direction in which the elongated holes (33, 34) extend into the longitudinally elongated hole 34 of the left side plate 24 of the upper fixing bracket 5 and the laterally elongated hole 33 of the left side plate 19 of the upper column bracket 4. It is movably fitted. Further, the rotation of the second portion 37 </ b> B is restricted by the vertical hole 34 by forming a two-sided width or the like in a portion that fits into the vertical hole 34 of the left side plate 24.

  In the cam 36 and the cam follower 37, cam protrusions 47 are formed on the contact surfaces of each other. Therefore, as the cam 36 and the cam follower 37 ride on each other as the cam 36 and the cam follower 37 rotate relative to each other, the cam 36 moves the cam follower 37 in the axial direction of the rotary shaft 6 (same as the left-right direction Y). Then, the cam follower 37 is pressed against the left side plate 24 of the upper fixing bracket 5.

  A first interposed member 38 and a second interposed member 39 are interposed between the nut 35 screwed into the right end 6 </ b> A of the rotating shaft 6 and the right plate 23 of the upper fixing bracket 5. The first interposed member 38 has a first portion 38A and a second portion 38B. The first portion 38 </ b> A of the first interposed member 38 extends along the outer side surface (right side surface) of the right side plate 23 of the upper fixing bracket 5. The second portion 38 </ b> B of the first interposed member 38 extends in the longitudinally elongated hole 34 of the right side plate 23 of the upper fixing bracket 5 and the laterally elongated hole 33 of the right side plate 18 of the upper column bracket 4 in the direction in which each elongated hole (33, 34) extends. It is fitted so that it can move along. In addition, the rotation of the second portion 38 </ b> B is restricted by the vertically long hole 34 by forming a two-sided width or the like in a portion that fits into the vertically long hole 34 of the right side plate 23.

  The second interposed member 39 is interposed between a thrust washer 40 interposed between the first portion 38A of the first interposed member 38 and the nut 35, and between the thrust washer 40 and the first portion 38A of the first interposed member 38. And a needle roller bearing 41 for thrust. The nut 35 can rotate smoothly together with the rotating shaft 6 by the action of the second interposed member 39 including the needle roller bearing 41.

  As the operating lever 7 is operated, the cam 36 rotates relative to the cam follower 37, whereby the cam follower 37 moves in the axial direction of the rotating shaft 6 (right side in the left-right direction Y). Since the pair of side plates (the right side plate 23 and the left side plate 24) of the upper fixing bracket 5 are sandwiched and tightened between the moved cam follower 37 and the first interposed member 38, each side plate (right side plate) of the upper fixing bracket 5 is clamped. 23, the left side plate 24) are pressed against the corresponding pair of side plates (the right side plate 18, the left side plate 19) of the upper column bracket 4. As a result, the column tube 3 is fixed in the axial direction X and the orthogonal direction Z (this state is referred to as a “fixed state”), and tilt lock and telescopic lock are achieved.

  Next, from the fixed state, the operation lever 7 is rotated in the opposite direction. Then, the cam 36 rotates with respect to the cam follower 37 as the operation lever 7 rotates. Thereby, the cam follower 37 moves in the axial direction of the rotating shaft 6 (left side in the left-right direction Y). Then, the clamping of the pair of side plates (the right side plate 23 and the left side plate 24) of the upper fixing bracket 5 is released between the cam follower 37 and the first interposed member 38. Therefore, the side plates (the right side plate 23 and the left side plate 24) of the upper fixing bracket 5 are released from the pressure contact with the corresponding pair of side plates (the right side plate 18 and the left side plate 19) of the upper column bracket 4. Thereby, the column tube 3 is in a state in which it can move in the axial direction X and the orthogonal direction Z (this state is referred to as a “released state”), and tilt adjustment and telescopic adjustment are possible. Specifically, the telescopic adjustment is possible by moving the rotary shaft 6 along the laterally long hole 33, and by rotating around the tilt center axis 17B by moving the rotary shaft 6 along the longitudinally long hole 34. Tilt adjustment is possible.

  FIG. 3A is a cross-sectional view of the main part of the steering column device 1 cut along the axial direction X, and shows a state in which the pressing member 42 is in the pressing position, and FIG. These show the state after the pressing member 42 has moved to the release position from the state of FIG. Here, the horizontal direction in FIG. 3 coincides with the axial direction X in FIG. Further, the direction perpendicular to the paper surface in FIG. 3 coincides with the left-right direction Y in FIG. Further, the vertical direction in FIG. 3 coincides with the orthogonal direction Z in FIG. Further, the right side in FIG. 3 is the steering member 8 side (rear side of the vehicle body 14) in FIG. Further, the left side in FIG. 3 is the steering mechanism 13 side (the front side of the vehicle body 14) in FIG.

In the following, description will be given with reference to FIG. 3 in addition to FIG. 1 and FIG.
First, referring to FIG. 2, as described above, the pressing member 42 is a member that presses and fixes the inner tube 32 against the outer tube 31 in accordance with the operation of the operation lever 7. The pressing member 42 is connected to the rotating shaft 6 and includes a fixed portion 43, an eccentric cam 44, and a ring 45.

The fixing portion 43 has a cylindrical shape extending in the left-right direction Y. The fixing portion 43 is fitted between the pair of side plates (the right side plate 18 and the left side plate 19) of the upper column bracket 4 so as to be integrally rotatable with the rotary shaft 6.
Referring also to FIG. 3A, the eccentric cam 44 is substantially elliptical when viewed from the left-right direction Y. The eccentric cam 44 is integrally formed in the approximate center of the fixed portion 43 in the left-right direction Y (see FIG. 2), and has a center of gravity at a position shifted from the central axis of the rotating shaft 6. Therefore, the eccentric cam 44 rotates eccentrically in conjunction with the rotation of the rotating shaft 6.

  The ring 45 has a circular shape (perfect circle shape) when viewed from the left-right direction Y. The ring 45 is externally fitted to the eccentric cam 44. The ring 45 of this embodiment has the same inner diameter as the long side of the substantially elliptical eccentric cam 44, and is externally fitted to the eccentric cam 44 so as to be integrally rotatable, and is located at the same position as the eccentric cam 44. Has a center of gravity. Therefore, the ring 45 rotates eccentrically as the eccentric cam 44 rotates eccentrically in conjunction with the rotation of the rotating shaft 6. Of course, a ring 45 having an inner diameter larger than the long side of the substantially elliptical eccentric cam 44 is also applicable. In this case, the ring 45 is externally fitted so as to ride on the eccentric cam 44 from above, while rotating relative to the eccentric cam 44 (sliding) as the eccentric cam 44 rotates eccentrically. ) Reciprocate up and down (orthogonal direction Z).

Here, the outer tube 31 is formed with a through hole 31E into which the eccentric cam 44 and the ring 45 can be inserted. When viewed from the orthogonal direction Z, the through hole 31E exists at the same position as the eccentric cam 44 and the ring 45. The through hole 31E is larger than the eccentric cam 44 and the ring 45 in the left-right direction Y and the axial direction X.
The state shown in FIG. 3A is a state in which the center of gravity of the eccentric cam 44 is moved to the uppermost side in the orthogonal direction Z by the rotation of the rotating shaft 6. In this state, the eccentric cam 44 and the ring 45 (at least the ring 45) are inserted through the through hole 31E and protrude into the inner space 31F of the outer tube 31. Therefore, the outer peripheral surface 45A of the ring 45 (the surface of the pressing member 42) is in contact with the outer peripheral surface 32C of the inner tube 32 from below. By this contact, the outer peripheral surface 32C of the inner tube 32 is pressed against the inner peripheral surface 31C of the outer tube 31 from below. The position of the ring 45 at this time (position of the pressing member 42) is defined as a “pressing position”. When the outer peripheral surface 32C of the inner tube 32 is pressed against the inner peripheral surface 31C of the outer tube 31, rattling between the outer tube 31 and the inner tube 32 can be prevented.

  The state shown in FIG. 3B is a state in which the rotary shaft 6 is rotated from the pressing position, and the center of gravity of the eccentric cam 44 is moved to the lowest side in the orthogonal direction Z. In this state, the eccentric cam 44 and the ring 45 are retracted from the inner space 31F of the outer tube 31 to the lower outer side of the outer tube 31. Therefore, the outer peripheral surface 45A of the ring 45 and the outer peripheral surface 32C of the inner tube 32 are not in contact with each other. Thereby, the pressing of the inner tube 32 against the outer tube 31 is released. The position of the ring 45 (position of the pressing member 42) at this time is defined as a “release position”.

  Thus, the pressing member 42 moves in conjunction with the rotation of the rotary shaft 6 between the pressing position (see FIG. 3A) and the release position (see FIG. 3B). In other words, the ring 45 of the pressing member 42 moves between the pressing position and the release position as the eccentric cam 44 rotates eccentrically in conjunction with the rotation of the rotating shaft 6. Here, as described above, the rotation shaft 6 rotates around the shaft in accordance with the operation of the operation lever 7. Therefore, the eccentric cam 44 and the ring 45 rotate eccentrically in conjunction with the change of the column tube 3 between the fixed state and the released state. Specifically, as the operation lever 7 rotates, the pressing member 42 moves (rotates) toward the pressing position. When the operation lever 7 reaches the position where the column tube 3 is fixed, the pressing member 42 reaches the pressing position shown in FIG. Further, from this state, as the operation lever 7 is rotated in the opposite direction, the pressing member 42 moves (rotates) toward the release position. When the operation lever 7 reaches the position where the column tube 3 is in the release state, the pressing member 42 reaches the release position shown in FIG.

  In such a steering column device 1, the force required to operate the operation lever 7 (referred to as “lever operation force”) is reduced, and the operation force during telescopic adjustment (the steering shaft 2 and the column tube 3 are expanded and contracted). This is a force necessary to reduce the EA load and the detachment load. Against this background, in the present invention, there is a request for reducing these operating forces and variations (of EA load and separation load), and there is also a request for reducing the operating amount (operating angle) of the operating lever 7. This time, the correlation between the friction between the inner tube 32 and the pressing member 42 and the operation force, operation angle, and variation thereof (the greater the friction, the greater the operation force, operation angle, and variation). Turned out for the first time.

Therefore, in the steering column device 1, the friction reducing material 100 for reducing the friction is provided on at least one of the inner tube 32 and the pressing member 42 (here, the ring 45). Examples of the friction reducing material 100 include Teflon (registered trademark) and grease.
Here, “providing the friction reducing material 100” means that the friction reducing material 100 is applied (coated) to at least one of the outer peripheral surface 32C of the inner tube 32 and the outer peripheral surface 45A of the ring 45 (the surface of the pressing member 42). In addition, at least one of the inner tube 32 and the ring 45 (the pressing member 42) is constituted by the friction reducing material 100. When the friction reducing material 100 is applied to at least one of the inner tube 32 and the pressing member 42 (here, the ring 45), the inner tube 32 and the pressing member 42 can be combined with each other without considering the friction coefficient of each material of the inner tube 32 and the pressing member 42. Friction with the pressing member 42 can be reduced. That is, it is possible to increase the choice of materials for the inner tube 32 and the pressing member 42. When at least one of the inner tube 32 and the pressing member 42 (here, the ring 45) is configured by the friction reducing material 100, it is not necessary to provide the friction reducing material 100 in post-processing. Therefore, it can contribute to the manufacturing cost reduction of the steering column apparatus 1. In this embodiment, the friction reducing material 100 is applied to both the inner tube 32 and the outer peripheral surface 45A of the ring 45 (the surface of the pressing member 42). Specifically, the friction reducing material 100 is provided in all the regions that can contact each other in the inner tube 32 and the ring 45.

  First, the lever operation force reduction will be described. When operating the operation lever 7, the outer peripheral surface 45 </ b> A of the ring 45 pushes up the inner tube 32 along the orthogonal direction Z while sliding with respect to the outer peripheral surface 32 </ b> C of the inner tube 32. Therefore, if the friction reducing material 100 is provided at least on the outer peripheral surface 45 </ b> A of the ring 45 (all areas that can come into contact with the inner tube 32), the friction between the ring 45 and the inner tube 32 is reduced. Thereby, the lever operating force for pressing the inner tube 32 against the inner peripheral surface 31C of the outer tube 31 can be kept low. In addition, the inner tube 32 can be pressed against the inner peripheral surface 31 </ b> C of the outer tube 31 even when the operation amount (operation angle) of the operation lever is small compared to the case where the friction reducing material 100 is not provided. As a result, in the configuration in which the inner tube 32 is pressed against the outer tube 31 in conjunction with the operation of the operation lever 7, lever operability (operation feeling) can be improved.

Furthermore, since the variation in lever operating force is reduced by reducing the friction, it is possible to save labor when inspecting the lever operating force in the production line of the steering column device 1, and the production cost is reduced accordingly. Reduction can be achieved.
Next, the telescopic operation force reduction will be described. Telescopic adjustment is performed by a user (driver or the like) moving the steering member 8 in the axial direction X and moving the outer tube 31 relative to the inner tube 32 in a state where the pressing member 42 is in the release position. At that time, telescopic adjustment is performed in a state where the outer peripheral surface 32C of the inner tube 32 and the inner peripheral surface 31C of the outer tube 31 are in contact, and friction is generated between the inner tube 32 and the outer tube 31. Therefore, if the friction reducing material 100 is provided on the inner tube 32, in addition to the friction between the inner tube 32 and the pressing member 42, the friction between the inner tube 32 and the outer tube 31 is also reduced. Therefore, the operation force (telescopic operation force) required when the inner tube 32 and the outer tube 31 are relatively moved (telescopic movement) in the axial direction X of the steering shaft 2 can be reduced. That is, the user can perform telescopic adjustment smoothly. Even when telescopic adjustment is performed in a state where the pressing of the pressing member 42 against the inner tube 32 is not completely released, the friction reducing material 100 is provided on at least one of the inner tube 32 and the ring 45. Friction between the pressing member 42 and the inner tube 32 is reduced. Therefore, the user can perform telescopic adjustment smoothly.

  Then, the variation in EA load and separation load variation will be described. During the secondary collision, the outer tube 31 moves relative to the inner tube 32. At this time, along with the outer tube 31, the rotating shaft 6, the upper column bracket 4, and the upper fixing bracket 5 also move relative to the inner tube 32. At that time, as described above, the pin 28 supporting the upper fixing bracket 5 to the vehicle body 14 is broken. During the secondary collision, the pressing member 42 is in the pressing position, so friction is generated between the outer peripheral surface 45A of the ring 45 and the outer peripheral surface 32C of the inner tube 32. Further, since the inner tube 32 is pressed against the outer tube 31, friction occurs between the outer peripheral surface 32 </ b> C of the inner tube 32 and the inner peripheral surface 31 </ b> C of the outer tube 31. Therefore, the impact of the secondary collision is mainly caused by the friction between the ring 45 and the inner tube 32, the friction between the inner tube 32 and the outer tube 31, and the friction between the upper shaft 21 and the lower shaft 22. And by the breakage of the pin 28. Therefore, the friction between the ring 45 and the inner tube 32 affects the separation load (load at the initial stage of impact) and the EA load (load necessary for shock absorption) to some extent. Since the frictional force here varies widely, the ratio (contribution rate) of the friction between the ring 45 and the inner tube 32 and the friction between the inner tube 32 and the outer tube 31 to the separation load and the EA load is large. When it is large, variations in the EA load and the separation load become large. Therefore, if the friction reducing material 100 is provided on the ring 45 or the inner tube 32, the friction between the pressing member 42 and the inner tube 32 is reduced, and the contribution ratio of the friction to the EA load and the separation load is reduced. On the other hand, since the contribution rate of the breaking load of the pin 28 that is easy to control increases, the EA load and the detachment load are stabilized correspondingly. Further, if the friction reducing material 100 is provided on the inner tube 32, the friction between the inner tube 32 and the outer tube 31 is reduced, so that the contribution ratio of the friction to the EA load is reduced, and the pin 28 As a result, the EA load and the separation load are stabilized.

Further, if the friction reducing material 100 is provided on both the ring 45 and the inner tube 32, the contribution ratio of friction to the EA load is further reduced, and the contribution ratio of fracture of the pin 28 is further increased. In addition, the separation load is further stabilized.
As described above, friction (friction between the pressing member 42 and the inner tube 32 or friction between the inner tube 32 and the outer tube 31) occurs in so-called EA (Energy Absorption) load or separation load in the secondary collision. Since the contribution ratio (contribution ratio) can be reduced by the friction reducing material 100, it is possible to suppress variations in the EA load and the separation load due to the friction.

By providing the friction reducing material 100 in this way, the lever operating force is reduced (reduced by about 5N compared to the case without the friction reducing material 100) or the telescopic operating force is reduced (when the friction reducing material 100 is not provided). Compared to a case where the friction reducing material 100 is not provided, it is possible to reduce variations in the EA load and the detachment load (reduced by about 1%).
FIG. 4 is a diagram in which a modification is applied to FIG. 2, and shows a case where the outer peripheral surface 32C of the inner tube 32 and the inner peripheral surface 31C of the outer tube 31 are spline-fitted. Here, the direction orthogonal to the paper surface in FIG. 4 coincides with the axial direction X in FIG. Also, the vertical direction in FIG. 4 coincides with the orthogonal direction Z in FIG. Further, the left-right direction in FIG. 2 coincides with the left-right direction Y in FIG. 4 is the steering member 8 side (rear side of the vehicle body 14). 4 is the steering mechanism 13 side (the front side of the vehicle body 14).

Hereinafter, description will be made with reference to FIG. 4 in addition to FIGS.
Referring to FIG. 4, a plurality (four in this embodiment) of first ribs 32 </ b> D extending in the axial direction X are formed on the outer peripheral surface 32 </ b> C of the inner tube 32. The first ribs 32D are arranged at equal intervals in the circumferential direction of the outer peripheral surface 32C. On the other hand, a plurality of second ribs 31G are formed on the inner peripheral surface 31C of the outer tube 31 at positions that fit between adjacent first ribs 32D of the inner tube 32 (four in this embodiment). Thus, the outer peripheral surface 32C of the inner tube 32 and the inner peripheral surface 31C of the outer tube 31 may be spline-fitted. In that case, it is possible to prevent the inner tube 32 and the outer tube 31 from rotating unexpectedly in the circumferential direction during transportation of the column tube 3 (that is, the steering column device 1).

  Further, the pressing member 42 may not include the ring 45 (a configuration including only the eccentric cam 44). In this case, the eccentric cam 44 moves between the pressing position (see FIG. 3A) and the release position (see FIG. 3B) by rotating eccentrically in conjunction with the rotation of the rotating shaft 6. At the pressing position, the outer peripheral surface 44 </ b> A of the eccentric cam 44 contacts the outer peripheral surface 32 </ b> C of the inner tube 32. Thereby, the inner tube 32 is pressed against the outer tube 31. At the release position, the outer peripheral surface 44A of the eccentric cam 44 and the outer peripheral surface 32C of the inner tube 32 do not contact each other. Thereby, the pressing of the inner tube 32 against the outer tube 31 is released. Also in this case, the friction reducing material 100 may be applied to at least one of the outer peripheral surface 32C of the inner tube 32 and the outer peripheral surface 44A of the eccentric cam 44 (the surface of the pressing member 42). Alternatively, the inner tube 32 itself and / or the eccentric cam 44 itself may be configured by the friction reducing material 100.

The present invention is not limited to the embodiment described above, and various modifications can be made within the scope of the claims.
For example, the through hole 31E of the outer tube 31 may have a cutout shape in which the front end portion 31B of the outer tube 31 is cut out to the rear side.

  DESCRIPTION OF SYMBOLS 1 ... Steering column apparatus, 2 ... Steering shaft, 3 ... Column tube, 6 ... Rotating shaft, 7 ... Operation lever, 8 ... Steering member, 31 ... Outer tube, 31C ... Inner peripheral surface, 32 ... Inner tube, 32C ... Outer periphery Surface, 42 ... Pressing member, 44 ... Eccentric cam, 44A ... Outer peripheral surface, 45 ... Ring, 45A ... Outer peripheral surface, 100 ... Friction reducing material, X ... Axial direction, Y ... Left and right direction

Claims (6)

An inner tube into which a steering shaft to which a steering member is connected is inserted; and an outer tube that is externally fitted to the inner tube; and the inner tube and the outer tube are relatively moved in the axial direction of the steering shaft. Possible column tube,
A rotating shaft that extends in a direction intersecting the axial direction, to which an operating lever is attached, and that rotates around the axis in accordance with the operation of the operating lever;
Between the pressing position that abuts the outer peripheral surface of the inner tube and presses the inner tube against the inner peripheral surface of the outer tube, and the release position that releases the pressing of the inner tube against the outer tube. A pressing member movable in conjunction with rotation;
A steering column device, comprising: a friction reducing material that is provided on at least one of the inner tube and the pressing member and reduces friction between the inner tube and the pressing member.   The steering column device according to claim 1, wherein the friction reducing material is applied to at least one of an outer peripheral surface of the inner tube and a surface of the pressing member.   The steering column device according to claim 1, wherein at least one of the inner tube and the pressing member is made of the friction reducing material.   The pressing member includes an eccentric cam that is connected to the rotating shaft and is movable between the pressing position and the release position by rotating eccentrically in conjunction with rotation of the rotating shaft. The steering column device according to any one of claims 1 to 3. An eccentric cam connected to the rotating shaft and rotating eccentrically in conjunction with the rotation of the rotating shaft;
The pressing member is a ring that is externally fitted to the eccentric cam, and moves between the pressing position and the release position in response to the eccentric cam rotating eccentrically in conjunction with the rotation of the rotating shaft. A steering column device according to any one of claims 1 to 3, further comprising a ring that can be moved at a distance.   The steering column device according to any one of claims 1 to 5, wherein the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube are spline-fitted.

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