Steering device and energy absorption mechanism of steering device

Abstract

To provide a steering device making it possible to upgrade the efficiency in attaching an energy absorption mechanism to an inner tube and a drive unit that moves the inner tube.SOLUTION: A steering device 1 includes an inner tube 3 provided in a column housing 9 so that the inner tube can move with respect to the column housing 9, a drive unit 5 that includes an output part 11 and a body 13 included in the column housing 9 and that drives the inner tube 3 by means of the output part 11, and an energy absorption unit 7 that is formed as a unit, is interposed between the inner tube 3 and drive unit 5, and absorbs an impact force applied to the inner tube 3.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a steering device and an energy absorbing mechanism for the steering device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a steering device has been disclosed that has a structure in which a shock absorbing member and a retainer are fastened to an inner tube by rivets (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-152635 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional steering apparatus, the shock absorbing member and the retainer are fastened to the inner tube by rivets, and since a number of parts must be fastened at the same time, the assembly is complicated and difficult to assemble.

[0005] An object of the present invention is to provide a steering device and an energy absorption mechanism for a steering device that can improve the ease of assembling the energy absorption mechanism to an inner tube and a drive unit for moving the inner tube. [Means for solving the problem]

[0006] A steering device according to one aspect of the present invention is a steering device comprising an inner tube provided in a column housing so as to be movable relative to the column housing, an output section, and a main body section provided in the column housing, the steering device having a drive section that drives the inner tube via the output section, and an energy absorption section that is unitized and provided between the inner tube and the drive section, and is configured to absorb impact forces applied to the inner tube by fixing a specified portion to the inner tube and fixing another specified portion to the output section of the drive section.

[0007] In a steering device according to this aspect of the present invention, the energy absorbing portion is configured to include an inner tube side member, a drive unit side member, and impact force absorbing material, a predetermined portion of the inner tube side member is a predetermined portion of the energy absorbing portion that is fixed to the inner tube, and a predetermined portion of the drive unit side member is a predetermined other portion of the energy absorbing portion that is fixed to the output portion of the drive unit, one portion of the impact force absorbing material engages with the inner tube side member and the other portion of the impact force absorbing material engages with the drive unit side member, and is configured such that when an impact force is applied to the inner tube, the impact force absorbing material deforms to absorb the impact force.

[0008] In a steering device according to this aspect of the present invention, the inner tube side member and the drive unit side member are joined by a shear pin, and when an impact force of a predetermined magnitude is applied to the inner tube, the shear pin breaks before the impact force absorbing material deforms, and the impact force absorbing material deforms after this breakage.

[0009] In a steering device according to this aspect of the present invention, the output portion of the drive unit and the drive unit side member are joined using a bracket formed in an "L" shape and having a first flat portion fixed to the output portion of the drive unit and a second flat portion fixed to the drive unit side member.

[0010] An energy absorption mechanism for a steering device according to one aspect of the present invention comprises an inner tube side member, a drive unit side member and impact force absorbing material, and is unitized, the inner tube side member is installed on the inner tube, the drive unit side member is installed on the output section, one portion of the impact force absorbing material engages with the inner tube side member and the other portion of the impact force absorbing material engages with the drive unit side member, and the impact force absorbing material is configured to deform to absorb the impact force applied to the inner tube, the inner tube engages so as to be able to move relative to a column housing, and the output section is an output section of a drive section comprising a main body section provided on the column housing, and the energy absorption mechanism for a steering device drives the inner tube by the output section. Effect of the Invention

[0011] According to the present invention, it is possible to provide a steering device and an energy absorption mechanism for a steering device that can improve the ease of assembling the energy absorption mechanism to the inner tube and the drive unit for moving the inner tube. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view of a steering device according to an embodiment of the present invention. [Diagram 2] 1 is an exploded perspective view of a steering device according to an embodiment of the present invention; [Diagram 3] 1 is a diagram showing an inner tube side member (detachment plate), a drive unit side member (telescopic bracket), and an impact force absorbing material (bending plate) that configure the energy absorption mechanism (energy absorbing unit) of the steering device according to an embodiment of the present invention. FIG. [Figure 4] 4 is a view taken along the arrow IV in FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A steering device 1 according to an embodiment of the present invention is installed and used in, for example, a vehicle. As shown in Fig. 1 to Fig. 4, the steering device 1 includes an inner tube 3, a drive unit (inner tube drive mechanism) 5, and an energy absorbing unit (energy absorbing mechanism) 7.

[0014] Here, for ease of explanation, a predetermined direction in the steering device is defined as the X direction, a predetermined direction perpendicular to the X direction is defined as the Y direction, and a direction perpendicular to the X direction and Y direction is defined as the Z direction.

[0015] The inner tube 3 is formed in a tubular (for example, cylindrical) shape, and is provided in the column housing 9 by engaging with the column housing 9 in a sliding manner. The inner tube 3 is capable of moving relative to the column housing 9 in the extension direction of the central axis of the inner tube 3 (telescopic direction; Z direction) by the above-mentioned sliding.

[0016] The column housing 9 is formed in a generally cylindrical shape, and is located outside the inner tube 3. The inner tube 3 is provided in the column housing 9 so as to penetrate through the column housing 9.

[0017] The inner tube driving mechanism 5 includes an output section (driving body; moving body) 11 and a main body section (casing) 13 that is integrally provided (fixed) to the column housing 9. The inner tube 3 is driven (moved) by the moving body 11 that moves in the Z direction relative to the casing 13.

[0018] The energy absorbing mechanism 7 is unitized (integrated) in advance, and is provided between the inner tube 3 and the moving body 11 of the inner tube drive mechanism 5. The energy absorbing mechanism 7 has a predetermined portion 25 fixed to the inner tube 3, and another predetermined portion 27 fixed to the moving body 11 of the inner tube drive mechanism 5. This is configured to mitigate the impact force (see arrow A1 in FIG. 1) applied to the inner tube 3. In other words, it is configured to absorb the energy of the impact force in the Z direction at the time of the secondary collision to mitigate the impact force.

[0019] Since the energy absorbing mechanism 7 is previously formed as a unit, the energy absorbing mechanism 7 is assembled separately from the inner tube 3 and the inner tube drive mechanism 5.

[0020] The energy absorbing mechanism 7 is configured to include an inner tube side member 15, a drive unit side member (telescopic bracket) 17, and an impact force absorbing material (bending plate) 19. The inner tube side member 15 is configured to include, for example, a release plate 21 and a telescopic plate 23.

[0021] A predetermined portion of the inner tube side member 15 serves as a predetermined portion 25 of the energy absorbing mechanism 7 that is fixed to the inner tube 3. A predetermined portion of the telescopic bracket 17 serves as another predetermined portion 27 of the energy absorbing mechanism 7 that is fixed to the moving body 11 of the inner tube drive mechanism 5 via a bracket 29, for example.

[0022] One portion (first portion) 31 of the bending plate 19 engages with the inner tube side member 15 (detachment plate 21), and the other portion (second portion) 33 of the bending plate 19 engages with the telescopic bracket 17. When an impact force is applied to the inner tube 3, the bending plate 19 is configured to deform (for example, plastically deform) to absorb the impact force.

[0023] As described above, the inner tube side member 15, the telescopic bracket 17, and the bending plate 19 that constitute the energy absorption mechanism 7 are previously unitized. That is, the energy absorption mechanism 7 is assembled separately from the inner tube 3, the inner tube drive mechanism 5, and other components. The energy absorption mechanism 7 is then installed on the inner tube 3 and the inner tube drive mechanism 5 while maintaining the assembled state, so as to function.

[0024] In the steering device 1, the inner tube side member 15 (detachment plate 21) and the telescopic bracket 17 are joined (fastened) to each other by a plurality of (for example, three) shear pins 35 (see FIG. 4).

[0025] When an impact force of a predetermined magnitude is applied to the inner tube 3, the shear pin 35 breaks (shear fracture) and at the same time the bending plate 19 starts to deform (starts plastic deformation). Then, the connection between the inner tube side member 15 (detachment plate 21) and the telescopic bracket 17 is released.

[0026] The energy value increases once when the shear pin 35 breaks, and then as the bending plate 19 undergoes plastic deformation, the energy value increases above the energy value at the time of breakage, and then the energy value becomes constant by the time the plastic deformation is completed.

[0027] The steering device 1 is provided with a bracket 29. The bracket 29 joins (fixes) the movable body 11 of the inner tube drive mechanism 5 and the telescopic bracket 17 to each other. The bracket 29 is configured to include a first flat plate-shaped portion 37 and a second flat plate-shaped portion 39. When viewed in the Z direction, the bracket 29 is formed in an "L" shape.

[0028] The first flat plate portion 37 is fixed to the moving body 11 of the inner tube driving mechanism 5. The second flat plate portion 39 is fixed to the telescopic bracket 17 (the predetermined other portion 27) of the energy absorbing mechanism 7.

[0029] Here, the state in which the inner tube drive mechanism 5 on which the bracket 29 is installed is appropriately positioned and oriented relative to the energy absorbing mechanism 7 is referred to as the pre-bracket / driver installation state. In the pre-bracket / driver installation state, the "L"-shaped bracket 29 and the inner tube drive mechanism 5 are appropriately moved (for example, translated) relative to the energy absorbing mechanism 7. This causes the "L"-shaped bracket 29 to engage with the energy absorbing mechanism 7 (telescopic bracket 17) and be temporarily installed.

[0030] From this temporary installation state, the "L" shaped bracket 29 and the telescopic bracket 17 are configured to be integrated with each other by using fasteners such as bolts 41. In this manner, the inner tube drive mechanism 5 can be easily installed on the energy absorption mechanism 7 by using the "L" shaped bracket 29 and fasteners such as bolts 41, as described above. Also, the inner tube side member 15 can be easily installed on the inner tube 3 by using fasteners such as bolts 43.

[0031] Here, the steering device 1 will be described in more detail.

[0032] As described above, the inner tube side member 15 is configured to include the detachment plate 21 and the telescopic plate 23. The detachment plate 21 and the telescopic plate 23 are formed, for example, in a flat plate shape.

[0033] The thickness direction of the detachment plate 21 and the thickness direction of the telescopic plate 23 coincide with each other and are in the X direction. The detachment plate 21 and the telescopic plate 23 overlap each other, and the telescopic plate 23 is located between the inner tube 3 and the detachment plate 21 in the X direction.

[0034] A recess 45 is provided in the center of the surface of the telescopic plate 23 facing the inner tube 3. The recess 45 extends over the entire length of the telescopic plate 23 in the Z direction. As a result, two protrusions 47 extending over the entire length of the telescopic plate 23 in the Z direction are formed on the surface of the telescopic plate 23 facing the inner tube 3. These two protrusions 47 come into contact with the side surfaces of the cylindrical inner tube 3, thereby stabilizing the position of the inner tube side member 15 relative to the inner tube 3.

[0035] The release plate 21 is provided with an engagement portion that engages with the engagement portion of the telescopic bracket 17. The release plate 21 and the telescopic bracket 17 are engaged with each other at these engagement portions, so that when the shear pin 35 breaks, the release plate 21 can slide relative to the telescopic bracket 17 and move in the Z direction. When the shear pin 35 is not broken, the release plate 21 and the telescopic bracket 17 are integrated together.

[0036] As already understood, the release plate 21 and the telescopic plate 23 are fixed to the inner tube 3 by bolts 43 .

[0037] The bending plate 19 is configured to include a bending plate main body 49 and a folded-back portion 51. The bending plate main body 49 is formed in a flat plate shape before being installed on the telescopic bracket 17. The bending plate main body 49 is configured to include a wide portion 53 having a large dimension (width dimension) in the Y direction, and a narrow portion 55 having a small dimension (width dimension) in the Y direction. The folded-back portion 51 is formed by slightly extending the wide portion 53, and the dimension (width dimension) in the Y direction of the folded-back portion 51 is equal to the width dimension of the wide portion 53.

[0038] As shown in FIG. 3, the telescopic bracket 17 is provided with a planar guide surface 57, a protrusion 59 protruding from the guide surface 57, and a contact surface 61.

[0039] The state in which the bending plate 19 is attached to the telescopic bracket 17 and the release plate 21 to form the energy absorbing mechanism 7 will be described.

[0040] The bending plate 19 is fixed to the detachment plate 21 at a folded portion 51, which is one portion in the longitudinal direction, and at a wide portion 53. More specifically, the wide portion 53 of the bending plate 19 is fixed to the detachment plate 21 by one of a pair of bolts 43. In addition, the folded portion 51 of the bending plate 19 is fixed to the detachment plate 21 by fitting into a groove in the detachment plate 21.

[0041] The width direction of the bending plate 19 is the Y direction. When viewed in the Y direction, as shown in Fig. 3, the elongated narrow portion 55 of the bending plate 19 is bent in an arc shape (semicircular arc shape) at the middle part in the longitudinal direction. The bending plate 19, except for the middle part of the narrow portion 55, extends long in the Z direction, and the thickness direction is the X direction.

[0042] 3, one side portion of the convex portion 59 is rounded in an arc shape (semicircular arc shape), and the middle portion of the narrow portion 55 abuts against the rounded portion of the convex portion 59 and bends in an arc shape. The radius of the arc of the narrow portion 55 is larger than the radius of the arc of the convex portion 59. The portion of the narrow portion 55 of the bending plate 19 that extends from the arc-shaped portion on the opposite side to the wide portion 53 abuts against a flat abutment surface 61 of the telescopic bracket 17.

[0043] One end of the bending plate 19 in the width direction is in contact with the planar guide surface 57 of the telescopic bracket 17. Furthermore, as shown in Fig. 3, a gap 63 is formed between the protruding portion 59 and a portion of the narrow width portion 55 of the bending plate 19 that extends from the arc-shaped portion on the opposite side to the wide width portion 53. That is, the protruding portion 59 and the portion that extends from the arc-shaped portion on the opposite side to the wide width portion 53 are separated from each other in the X direction.

[0044] 2, a through hole 67 is formed in the first flat plate portion 37 of the bracket 29. Then, a part of the movable body 11 fits into the through hole 67, so that the bracket 29 is installed on the movable body 11.

[0045] Here, a portion 65 (see FIG. 2) of the bracket 29 may be cut out to form a through hole 67 of the bracket 29 into a "U" shaped notch. Then, the bracket 29 is separated from the inner tube drive mechanism 5 and the position and posture of the bracket 29 relative to the inner tube drive mechanism 5 are kept in an appropriate state. Next, the bracket 29 is moved (translated). In this way, the bracket 29 may be temporarily installed on the inner tube drive mechanism 5. In this temporarily installed state, the bracket 29 is installed on the telescopic bracket 17 of the energy absorbing mechanism 7 using the bolts 41. In this way, the inner tube drive mechanism 5 may be installed on the energy absorbing mechanism 7.

[0046] Incidentally, the rigidity and strength of bracket 29, inner tube side member 15 and telescopic bracket 17 are greater than the rigidity and strength of shear pin 35 and bending plate 19. As a result, when an impact force of a predetermined magnitude is applied to inner tube 3, bracket 29, inner tube side member 15 and telescopic bracket 17 are not destroyed but only slightly elastically deformed.

[0047] Here, the rigidity of the bracket 29 may be reduced so that both the bending plate 19 and the bracket 29 undergo plastic deformation after an impact force of a predetermined magnitude is applied to the inner tube 3 and the shear pin 35 is destroyed. Note that even if the bracket 29 undergoes plastic deformation, it is assumed that the bracket 29 continues to be fixed to the inner tube drive mechanism 5 and the energy absorbing mechanism 7.

[0048] 2 and other drawings, the inner tube drive mechanism 5 is configured to include a motor 69, a screw 71, and a nut 73. The inner tube drive mechanism 5 is also configured to include an L-shaped drive mechanism bracket 75 that supports the screw 71 and the nut 73 (moving body 11). The drive mechanism bracket 75 is fastened to the column housing 9 via a fixing bolt (not shown). In this way, the main body 13 of the inner tube drive mechanism 5 is fixed to the column housing 9.

[0049] Here, we will explain the operation of the steering device 1. When an impact force of a predetermined magnitude is applied to the inner tube 3, first, all the shear pins 35 break. Next, the bending plate 19 deforms and absorbs the energy of the impact force.

[0050] The deformation of the bending plate 19 occurs when the folded portion 51 and the wide portion 53, and the detachment plate 21 shown in Fig. 3 move to the left in Fig. 3 relative to the telescopic bracket 17. The above-mentioned movement of the detachment plate 21, etc., causes the arc-shaped portion of the narrow portion 55 of the bending plate 19 that abuts against the protrusion 59 (the protrusion 59 of the telescopic bracket 17) to shift. That is, the length of the portion of the bending plate 19 that extends in the Z direction below the protrusion 59 becomes longer, and the length of the portion of the bending plate 19 that extends in the Z direction above the protrusion 59 becomes shorter.

[0051] In the steering device 1, the energy absorption mechanism 7 that absorbs the impact force during a secondary collision is unitized and can be easily installed between the inner tube 3 and the moving body 11 of the inner tube drive mechanism 5. This eliminates the need to fasten multiple parts simultaneously as in the conventional case, and improves the ease of assembling the energy absorption mechanism 7 to the inner tube 3 and the inner tube drive mechanism 5.

[0052] Furthermore, when it is desired to output a predetermined energy absorption load in the steering device 1 (when it is desired to adjust the value of the energy of the impact force to be absorbed), it is only necessary to change the unitized energy absorption mechanism 7. This makes it possible to easily change to a predetermined energy absorption load.

[0053] In the steering device 1, the energy absorbing mechanism 7 is configured to include an inner tube side member 15, a telescopic bracket 17, and a bending plate 19. The energy absorbing mechanism 7 is fixed to the inner tube 3, and is fixed to the moving body 11. The bending plate 19 is engaged with the inner tube side member 15 and the telescopic bracket 17, and is configured to deform and absorb the impact force when an impact force is applied to the inner tube 3. This makes it possible to absorb the impact force with a simple configuration. Also, by changing the specifications (shape, etc.) of the bending plate 19, the amount of energy of the impact force that can be absorbed, etc., can be changed.

[0054] In the steering device 1, the inner tube side member 15 and the telescopic bracket 17 are joined by a shear pin 35. The shear pin 35 is broken when an impact force of a predetermined magnitude is applied to the inner tube 3, and then the bending plate 19 is deformed. This makes it possible to control the load of energy absorption. In other words, by appropriately changing the outer diameter, number, material, etc. of the shear pin 35, it is possible to change the amount of energy of the impact force that can be absorbed by breaking the shear pin 35.

[0055] Furthermore, in the steering device 1, the movable body 11 of the inner tube drive mechanism 5 and the telescopic bracket 17 are joined using an "L" shaped bracket 29. This allows the energy absorbing mechanism 7, the inner tube drive mechanism 5, and the bracket 29 to be assembled to the inner tube 3 from, for example, one direction, improving ease of assembly.

[0056] Here, the energy absorbing mechanism 7 of the steering system will be described again.

[0057] The energy absorption mechanism 7 of the steering device comprises an inner tube side member, a drive unit side member, and impact force absorbing material, which are unitized such that the inner tube side member is installed on the inner tube, the drive unit side member is installed on the output unit, one portion of the impact force absorbing material engages with the inner tube side member and the other portion of the impact force absorbing material engages with the drive unit side member, and the impact force absorbing material deforms to absorb the impact force applied to the inner tube.

[0058] Moreover, in the energy absorption mechanism 7 of the steering device, the inner tube is engaged with the column housing so as to be able to move relative to the column housing, and the output part is an output part of a drive part having a main body part provided on the column housing, and the inner tube is driven by the output part.

[0059] Although the present embodiment has been described above, the present embodiment is not limited to this, and various modifications are possible within the scope of the gist of the present embodiment. [Explanation of symbols]

[0060] 1 Steering device 3. Inner tube 5 Drive unit (inner tube drive mechanism) 7 Energy absorption section (energy absorption mechanism) 9 Column Housing 11 Output section (driver; moving body) 13 Main body (housing) 15 Inner tube side member 17 Drive unit side member (telescopic bracket) 19 Impact absorbing material (bending plate) 25 Prescribed Area 27 Other parts as specified 29 Bracket 31 One side (first side) 33 The other part (second part) 35 Sharpin 37 First flat area 39 Second flat area

Claims

1. an inner tube mounted to the column housing so as to be movable relative to the column housing; a drive unit including an output unit and a main body unit provided in the column housing, the drive unit driving the inner tube by the output unit; an energy absorbing section which is unitized and provided between the inner tube and the driving section, and which is configured to absorb an impact force applied to the inner tube by fixing a predetermined portion to the inner tube and fixing another predetermined portion to an output portion of the driving section; A steering device having a

2. The energy absorbing section is configured to include an inner tube side member, a driving section side member, and an impact force absorbing material, a predetermined portion of the inner tube side member is a predetermined portion of the energy absorbing portion that is fixed to the inner tube, a predetermined portion of the drive unit side member is a predetermined other portion of the energy absorbing portion that is fixed to an output portion of the drive unit, 2. A steering device as described in claim 1, wherein one portion of the impact force absorbing material engages with the inner tube side member and the other portion of the impact force absorbing material engages with the drive unit side member, and when an impact force is applied to the inner tube, the impact force absorbing material deforms to absorb the impact force.

3. The inner tube side member and the drive unit side member are joined by a shear pin, 3. The steering device according to claim 2, wherein when an impact force of a predetermined magnitude is applied to the inner tube, the shear pin breaks before the impact force absorbing material deforms, and the impact force absorbing material deforms after the breakage.

4. 4. A steering device according to claim 2 or claim 3, wherein the output portion of the drive unit and the drive unit side member are joined using a bracket formed in an "L" shape and including a first flat portion fixed to the output portion of the drive unit and a second flat portion fixed to the drive unit side member.

5. the shock absorbing material is provided with an inner tube side member, a drive unit side member, and an impact force absorbing material and is formed into a unit, the inner tube side member is installed on the inner tube, the drive unit side member is installed on the output unit, one portion of the impact force absorbing material engages with the inner tube side member and the other portion of the impact force absorbing material engages with the drive unit side member, and the impact force absorbing material is configured to deform to absorb the impact force applied to the inner tube, the inner tube is movably engaged with a column housing; The output portion is an output portion of a drive portion configured with a main body portion provided in the column housing, and the inner tube is driven by the output portion. This is an energy absorption mechanism for a steering device.

Images