JP6699781B2 - Steering device - Google Patents

Description

  The present invention relates to a steering device mounted on an automobile or the like, and more particularly, to a technique for ensuring a power supply path of an electric component mounted on a steering wheel.

  In a recent automobile, a secondary collision energy is absorbed by contracting a steering column composed of two parts, an inner column and an outer column, in order to mitigate a shock received by a driver due to a secondary collision with a steering wheel at the time of an accident. Steering devices are widely used. In this type of steering device, the inner column and the outer column are slid relative to each other in the axial direction, so that the steering wheel moves toward the front of the vehicle and the energy absorbing means provided between the inner column and the outer column. Secondary collision energy is absorbed.

  For example, in the steering device described in Patent Document 1, the outer column arranged on the lower side is attached to the vehicle body via a tilt bracket or a tilt pivot, and the inner column arranged on the upper side is tightened by a tightening mechanism. It is held by the outer column. In this steering device, the inner column's advancing amount with respect to the outer column is set to be larger than the telescopic adjustment amount, and in the event of a secondary collision, the inner column is moved forward of the vehicle against the fastening friction force of the fastening mechanism. Moving.

  In such a steering device, it is required to smoothly absorb secondary collision energy when a driver with a light weight collides with the steering wheel. In order to achieve this, it is conceivable to reduce the tightening force by the tightening mechanism, but if the tightening force is reduced, the inner column holding force will decrease and the inner column and outer column will not fit. Rattling is likely to occur in the part. Therefore, in Patent Document 1, a low friction material treatment such as coating is applied to the outer peripheral surface of the inner column or the inner peripheral surface of the outer column to reduce the tightening friction force without reducing the tightening force.

  In the telescopic steering device, the steering shaft is generally composed of an inner shaft and an outer shaft that are spline-coupled in the steering column in order to achieve both transmission of steering torque and telescopic adjustment. In this case, a resin coating may be applied to one of the splines in order to prevent rattling noise due to a minute gap between the male spline and the female spline.

International publication WO2004/000627

  Electrical components such as horns and airbags are attached to the steering wheel of an automobile, and most of these electrical components are body grounds. Therefore, it is necessary to secure an energization path from the steering wheel to the vehicle body.

  However, when a low friction material coating is applied to the inner peripheral surface of the outer column or the outer peripheral surface of the inner column as described above, it is difficult to energize by the energizing path via the contact surface between the inner column and the outer column due to the coating. Becomes Further, when the spline fitting portion of the steering shaft is coated with a resin, the resin coating makes it difficult to energize the power supply path via the spline fitting portion.

  In view of the above problems, it is an object of the present invention to provide a steering device that secures a new energization path from the steering wheel to the vehicle body.

In order to solve the above problems, the present invention provides
A steering shaft that can expand and contract in the axial direction,
A steering column that includes an outer column and an inner column that are fitted to enable relative movement in the axial direction, and that rotatably supports the steering shaft,
An engaging member fixed to the inner column,
The outer column accommodates the engagement member, prevents rotation of the inner column via the engagement member, extends in the axial direction, and guides axial movement of the inner column; A pair of guide walls projecting outward in the radial direction on both the left and right sides of the guide groove and extending in the central axis direction, and a telescopic rearward of the inner column toward the rear of the vehicle by abutting against the engaging member arranged at the end of the guide groove. A vehicle rear side portion that defines an adjustment range, and a tightening portion that tightens the inner column ,
The guide groove is integrally formed with the pair of guide walls, and has a bottom portion facing the engaging member ,
The outer column is an integrally molded product including the guide groove, the vehicle rear side portion, and the bottom portion,
A steering device in which the guide groove and the bottom portion are present at least in the axial range of the tightening portion .
In order to solve the above problems, the present invention provides
A steering shaft that can expand and contract in the axial direction,
A steering column that includes an outer column and an inner column that are fitted to enable relative movement in the axial direction, and that rotatably supports the steering shaft,
An engaging member fixed to the inner column,
The outer column accommodates the engagement member, prevents rotation of the inner column via the engagement member, extends in the axial direction, and guides axial movement of the inner column; A pair of guide walls projecting outward in the radial direction on both the left and right sides of the guide groove and extending in the central axis direction, and a telescopic rearward of the inner column toward the rear of the vehicle by abutting against the engaging member arranged at the end of the guide groove. A vehicle rear side portion that defines an adjustment range, and a tightening portion that tightens the inner column,
The guide groove is integrally formed with the pair of guide walls, and has a bottom portion facing the engaging member,
The outer column is an integrally molded product including a diameter-enlarged portion that accommodates a steering assist mechanism that assists rotation of the steering shaft, the guide groove, the vehicle rear side portion, and the bottom portion,
A steering device in which the guide groove and the bottom portion are present at least in the axial range of the tightening portion.
As a result, a new energization path from the steering wheel to the vehicle body can be secured.

Preferably, the guide groove is capable of inserting the engaging member,
When the inner column is moved to the frontmost side of the vehicle in the telescopic adjustment, the guide groove is located on the vehicle front side of the engaging member.

Preferably, when the inner column moves to the frontmost side of the vehicle due to a secondary collision, the guide groove is located on the vehicle rear side of the engagement member.

Preferably, the engaging member has a conductive plate having a conductive portion integrally provided with an elastic portion that is in conductive contact with the bottom portion,
The outer column constitutes a part of a current-carrying path leading to the vehicle body,
The inner column and the outer column are configured to be able to conduct electricity via the engaging member and the conducting plate.

Further, preferably, the engagement member faces the bottom portion in a telescopic adjustment range.

  According to the steering device of the present invention, it is possible to provide a steering device in which a new energization path from the steering wheel to the vehicle body is secured.

FIG. 1 is a perspective view of a steering mechanism using a steering device according to a reference example , as viewed from diagonally left front. FIG. 2 is a perspective view of the steering device according to the reference example as seen from the diagonally left front side. FIG. 3 is a partially exploded perspective view of the steering device according to the reference example as seen from the diagonally left front side. FIG. 4 is a plan view of the steering device according to the reference example . FIG. 5 is a vertical sectional view of a steering device according to a reference example . FIG. 6 is a cross-sectional view showing a cross section VI-VI shown in FIG. FIG. 7 is an enlarged cross-sectional view around the upper stopper of the steering device according to the reference example . FIG. 8 is a sectional view showing a section taken along line VIII-VIII shown in FIG. FIG. 9 is a vertical cross-sectional view of the steering device according to the embodiment . FIG. 10 is a partially enlarged view of the vertical section shown in FIG. FIG. 11 is a cross-sectional view showing a cross section taken along line XI-XI shown in FIGS. 9 and 10. FIG. 12 is a partially enlarged view of the cross section shown in FIG.

  Hereinafter, an embodiment in which the present invention is applied to a steering device used for a tilt/telescopic adjustment type rack assist type electric power steering mechanism (hereinafter, simply referred to as a steering mechanism) and a partial modification thereof will be described in detail with reference to the drawings. Explained. In the description of the steering mechanism and the steering device, front and rear, left and right, and up and down are indicated by arrows in the drawings, and the position and direction of each member will be described accordingly. These directions match the direction of the vehicle when the steering device is mounted on the vehicle.

( Reference example )
FIG. 1 is a perspective view of a steering mechanism 1 using a steering device 2 according to a reference example of the present application as seen obliquely from the front. As shown in FIG. 1, the steering device 2 of the present reference example has a steering gear 103 via a steering shaft 3 and an intermediate shaft 102 that are pivotally supported by a steering column in order to reduce the force required to operate a steering wheel 101. The steering force transmitted to the rack is assisted by the electric assist mechanism 104, and the rack (not shown) is reciprocated left and right to steer the front wheels through the left and right tie rods 105 connected to the rack.

FIG. 2 is a perspective view of the steering device 2 according to the reference example of the present application as seen from the diagonally left front side. As shown in FIG. 2, the steering device 2 includes a steering shaft 3 that transmits a steering force, an aluminum alloy die-cast molded tubular outer column 10 that forms a front portion of the steering column, and a rear portion of the steering column. The inner column 11 made of steel pipe and the tilt bracket 12 that supports the outer column 10 on the vehicle body 100 (see FIG. 1) are the main components.

  The outer column 10 has an inner peripheral surface 13 (illustrated in FIG. 5) that is slightly larger than the outer diameter of the inner column 11, and the front portion of the inner column 11 is inserted radially inward from the vehicle rear side.

  The outer column 10 has a pivot boss 22 that holds a collar 21 made of steel pipe in a boss hole 22a penetrating in the left-right direction at the upper front end thereof, and a pivot bolt (not shown) inserted into the collar 21 is used. It is rotatably attached to the vehicle body 100.

  The outer column 10 is provided at its upper part with a current-carrying cover 15 made of a conductive metal material and long in the axial direction.

FIG. 3 is a partially exploded perspective view of the steering device 2 according to the reference example of the present application as seen from the diagonally left front side. FIG. 3 shows a state in which the energizing cover 15, the energizing plate 40 described below, and the stepped low head bolt 35 described below are removed.

  As shown in FIG. 3, the energization cover 15 has a thin plate shape that is long in the axial direction, and the front and rear ends thereof are formed in an arc shape.

  A guide groove 25, which extends in the radial direction and is long in the axial direction, is formed on the lower side of the energization cover 15, that is, on the upper portion of the outer column 10. The guide groove 25 accommodates an upper stopper 30, which will be described later, that limits the movement of the inner column 11.

  In FIG. 3, a guide member 31 forming the upper stopper 30, a current-carrying plate 40 removed from the upper stopper 30, and a stepped low head bolt 35 removed from the upper stopper 30 are shown. The energizing cover 15 and the energizing plate 40 form part of an energizing path from the inner column 11 to the outer column 10 as described later.

FIG. 4 is a plan view of the steering device 2 according to the reference example of the present application. As shown in FIG. 4, the energizing cover 15 is arranged so as to cover the guide groove 25 of the outer column 10. As a result, the energization cover 15 not only energizes as will be described later, but also prevents foreign matter from entering the inside of the outer column 10 through the guide groove 25 and inhibiting the rotation of the steering shaft 3.

(Steering shaft)
FIG. 5 is a vertical cross-sectional view of the steering device 2 according to the reference example of the present application. As shown in FIG. 5, the steering shaft 3 includes a cylindrical lower steering shaft 61 arranged on the front side of the vehicle, and a cylindrical upper steering shaft 62 arranged on the rear side of the vehicle and externally fitted to the lower steering shaft 61. Consists of.

  The lower steering shaft 61 can be formed by rolling or broaching a steel round bar as a raw material, and has a male spline 61a on the outer periphery of the latter half portion. A serration 61b is formed around the tip of the lower steering shaft 61 so that a universal joint (not shown) can be fitted on the serration 61b. A vehicle front side portion of the lower steering shaft 61 is rotatably supported by a ball bearing 27 fitted inside the front end portion of the outer column 10.

  The upper steering shaft 62 can be formed by drawing or broaching a steel pipe as a raw material, and has a female spline 62a fitted to the male spline 61a of the lower steering shaft 61 on the inner periphery of the front half portion. At the rear end of the upper steering shaft 62, there is formed a serration 62b to which a boss 101a (shown by a chain line in FIG. 5) of the steering wheel 101 is fitted. A vehicle rear side portion of the upper steering shaft 62 is rotatably supported by a ball bearing 29 fitted inside the rear end portion of the inner column 11.

  The lower steering shaft 61 and the upper steering shaft 62 are spline-coupled to each other to enable torque relative transmission and relative movement in the axial direction. A resin coating is applied to the male spline 61a of the lower steering shaft 61 to prevent rattling with the female spline 62a of the upper steering shaft 62.

(Position adjustment mechanism)
The steering device 2 adjusts a position in a rotation direction around a pivot bolt inserted into the pivot boss 22 when the steering device 2 is attached to the vehicle body 100 (hereinafter, referred to as “tilt adjustment”) in order to match a physique of a driver and the like, In addition, the axial position of the inner column 11 can be adjusted (hereinafter referred to as "telescopic adjustment").

  FIG. 6 is a cross-sectional view showing the VI-VI cross section of FIG. The vehicle body front side portion of the inner column 11 is fastened and fixed by the vehicle rear side portion of the outer column 10 in which a slit 26 that extends in the vehicle front-rear direction and is open to the vehicle rear side is formed. The fixation is released by the driver's operation, and the telescopic adjustment is made possible. The vehicle rear side portion of the outer column 10 is sandwiched and fixed by the tilt bracket 12 from both left and right sides. As described above, when the driver releases the fixing of the inner column 11 by the outer column 10, the vertical fixing by the tilt bracket 12 is also released at the same time, and the tilt adjustment is possible. These configurations will be specifically described below.

  The tilt bracket 12 has an upper plate 71 extending in the left-right direction and a pair of left and right side plates 72, 73 welded to the lower surface of the upper plate 71 and extending downward. The upper plate 71 is fastened to the vehicle body 100 by bolts 74 that pass through the bolt holes 71a. The distance between the side plates 72 and 73 is set to be slightly wider than the width of the outer column 10 in the left-right direction in the free state. The left and right side plates 72, 73 are formed with tilt adjusting slots 72a, 73a through which a tightening bolt 81 described later is inserted. The tilt adjusting slots 72a and 73a are formed in an arc shape centered on the above-described pivot bolt, and the tightening bolt 81 is movable during tilt adjustment.

  Around the lower part of the tilt bracket 12, there is provided a tightening mechanism 80 for fixing and releasing the outer column 10 and the inner column 11 according to the operation of the driver. The tightening mechanism 80 includes a tightening bolt 81 inserted from the left into the tilt adjusting long holes 72a, 73a and a through hole 28 penetrating in the left-right direction at a lower portion of the outer column 10 on the rear side of the vehicle, which will be described later. Using the cam mechanism, the outer column 10 and the inner column 11 are tightened from the outside of the pair of left and right side plates 72, 73 of the tilt bracket 12.

  As shown in FIG. 6, the tightening bolt 81 has an operating lever 82 (FIG. 2, FIG. 2) that is rotated between the head of the tightening bolt 81 and the left side plate 72 of the tilt bracket 12 in order from the head side. 3 and 4), a movable cam 83 that rotates integrally with the operation lever 82, and a fixed cam 84 whose right side portion is non-rotatably engaged with the tilt adjusting elongated hole 72a. Complementary inclined cam surfaces are formed on the surfaces of the fixed cam 84 and the movable cam 83 that face each other.

  When the driver turns the operation lever 82 to the tightening side, the mountain of the inclined cam surface of the movable cam 83 rides on the mountain of the inclined cam surface of the fixed cam 84 and pulls the tightening bolt 81 to the left while the fixed cam 84 is pulled. Press to the right. As a result, the pair of left and right side plates 72, 73 tightens the lower portion of the outer column 10 from the left and right, restricts the movement of the steering column in the tilt direction, and at the same time, the outer column 10 tightens the inner column 11 with the tightening friction force and friction. The frictional force generated on the plate 85 limits the axial movement of the inner column 11.

  On the other hand, when the driver rotates the operation lever 82 in the releasing direction, the pair of left and right side plates 72 and 73, which have a larger space in the free state than the width of the outer column 10 as described above, elastically return. As a result, both the restriction on the movement of the outer column 10 in the tilt direction and the restriction on the movement of the inner column 11 in the axial direction are released, and the driver can adjust the position of the steering wheel 101.

  A pressing plate 87 and a thrust bearing 88 are externally fitted to the tip side portion of the tightening bolt 81 protruding from the right side plate 73. A male screw 81a is formed around the tip of the tightening bolt 81, and a nut 89 is screwed in.

  A part of the outer column 10 facing the pair of left and right side plates 72, 73 of the tilt bracket 12 is formed around the fastening bolt 81 with an escape portion separated from the side plates 72, 73. The left and right friction plates 85 fixed to the inner column 11 by a lower stopper 50, which will be described later, and the end portions of the intermediate friction plate 86 are formed in the escape portion, and are sandwiched between the left and right friction plates 85. The left and right end plate portions 86a and 86b are arranged. The friction plate 85 and the intermediate friction plate 86 hold the inner column 11 by increasing a friction surface that generates a frictional force that resists a force that moves the inner column 11 when the inner column 11 is fixed. Are reinforced.

  As shown in FIG. 5, the friction plate 85 is long in the front-rear direction, and the portion through which the tightening bolt 81 is inserted has a long hole portion 85a that is long in the front-rear direction. As a result, when the tightening mechanism 80 releases the tightening, the tightening bolt 81 and the friction plate 85 are allowed to move relative to each other, thereby enabling telescopic adjustment.

  The intermediate friction plate 86 has a shape in which a round plate through which the tightening bolt 81 passes is formed in the center of a square plate-like member, and the lower portions of a pair of left and right end plate portions 86a and 86b facing each other are connected by a connecting plate portion 86c. Presents.

  As shown in FIG. 4, hook portions 91 and 92 are provided at the axially intermediate portions on the left and right side surfaces of the outer column 10 so as to project in the horizontal direction. Further, locking holes 71b and 71c are formed on both left and right front sides of the upper plate 71 of the tilt bracket 12. Coil springs 93 are stretched over the hook portions 91, 92 and the locking holes 71b, 71c, respectively. The coil spring 93 bears the weight of the steering column, the steering wheel 101, and the like during tilt adjustment, and lightens the tilt adjustment operation by the driver.

  As shown in FIGS. 2 and 3, a coil spring 95 is also stretched between the operation lever 82 and the tilt bracket 12. The coil spring 95 applies a preload so that the fixed cam 84 and the movable cam 83 do not rattle when the operation lever 82 is released.

  As shown in FIG. 5, the lower stopper 50 that fixes the friction plate 85 to the inner column 11 is attached to the lower surface of the inner column 11 on the tip side and is housed in the slit 26. The friction plates 85 are engaged with the locking arms 54 that project from the left and right side surfaces of the lower stopper 50 to the outside of the slit 26.

  A buffer holding portion 52 having a substantially L-shaped cross section is formed at the front end of the lower stopper 50 so as to protrude downward, and a buffer block 53 is attached to the front side of the buffer holding portion 52. The buffer block 53 defines a telescopic adjustment range (indicated by TAf in FIG. 5) toward the front of the inner column 11 by abutting on a portion of the outer column 10 on the front side of the slit 26 during the telescopic adjustment. .. The buffer block 53 is made of rubber and absorbs impact so that the resin pin 51 is not damaged even if it hits the vehicle front side portion of the outer column 10 that forms the slit 26 during telescopic adjustment.

(Shock absorption mechanism)
A resin coating having a low coefficient of friction is applied to the outer peripheral surface of the portion of the inner column 11 that is inserted into the outer column 10. Thereby, even if the tightening force of the outer column 10 by the tightening mechanism 80 is set to be large, the tightening frictional force generated by the tightening of the inner column 11 by the outer column 10 is kept relatively low.

  The lower stopper 50 is attached to the inner column 11 by a pair of front and rear resin pins 51. When the inner column 11 moves forward due to the impact of the secondary collision, the buffer block 53 mounted on the lower stopper 50 collides with the portion of the outer column 10 in front of the slit 26. When the impact due to this collision is larger than a predetermined magnitude, the resin pin 51 shears and breaks, and the inner column 11 separates from the lower stopper 50 and moves further forward without being restricted in movement by the friction plate 85. Will be able to.

  With such a configuration, even when a driver with a light weight collides with the steering wheel 101 due to a collision of the vehicle, the steering wheel 101 relatively easily moves forward together with the inner column 11, and the secondary collision occurs. The impact of is mitigated. Further, since the low friction material coating having a low friction coefficient can maintain a low tightening friction force even if the machining accuracy of the inner peripheral surface 13 of the outer column 10 is lowered, it is possible to reduce the machining cost. ..

(Upper stopper)
FIG. 7 is an enlarged sectional view around the upper stopper 30 shown in FIG. FIG. 8 is a cross-sectional view showing a section taken along line VIII-VIII shown in FIG.

  As shown in FIGS. 5 and 8, a pair of left and right guide walls 23 and 24 that project upward and extend in the front-rear direction are formed in the upper portion of the outer column 10, and a guide groove that penetrates radially between them and extends in the front-rear direction. 25 are provided. The upper stopper 30 is fixed to the inner column 11, its height is lower than that of the guide walls 23 and 24, and is accommodated inside the guide groove 25.

  The upper stopper 30 engages with the guide groove 25 to prevent relative rotation between the outer column 10 and the inner column 11, and also defines the axial relative movement range between the inner column 11 and the outer column 10. That is, the upper stopper 30 defines the telescopic adjustment range (indicated by symbol TAr in FIG. 5) to the rear of the inner column 11 by contacting the vehicle rear side portion of the outer column 10 forming the guide groove 25. By making contact with the vehicle front side portion of the outer column 10 forming the guide groove 25, the moving range of the inner column 11 at the time of a secondary collision (indicated by the symbol CP in FIG. 5) is defined.

  The upper stopper 30 includes a stepped low head bolt 35 having a hexagonal hole and a nut plate 36 fixed to the inner column 11, in which a resin injection-molded guide member 31 and a metal stopper base 32 are fixtures. It is configured by being attached to the inner column 11.

  The guide member 31 has a substantially oval shape in a plan view, and the left and right side surfaces of the guide member 31 face the inner surfaces 25a and 25b of the guide walls 23 and 24, respectively. As shown in FIGS. 7 and 8, a recess 31c into which the stopper base 32 is fitted is formed in the lower portion of the guide member 31. The guide member 31 can be formed of synthetic resin, rubber, or the like.

  As shown in FIGS. 7 and 8, the stopper base 32 has a through hole 32a at the center, into which the screw shaft 35a of the stepped low head bolt 35 is inserted. The lower surface of the stopper base 32 is formed into a curved surface having substantially the same curvature as the outer peripheral surface of the inner column 11, and is in surface contact with the inner column 11 as shown in FIG.

As shown in FIG. 7, the nut plate 36 has a boss portion 36a that fits into a radial through hole 11a formed in the inner column 11 in the center of the upper surface 36b, and from the upper end surface of the boss portion 36a. A screw hole 36c penetrating in the radial direction is formed at the lower end. The upper surface 36b of the nut plate 36 is formed into a curved surface having a curvature substantially the same as the curvature of the inner column 11, and as shown in FIG. It is in surface contact with the peripheral surface. In this reference example , after the stopper base 32 is fixed to the inner column 11 by caulking the boss portion 36a in the through hole 11a, the screw groove of the screw hole 36c is formed by tapping. Instead of the nut plate 36, the upper stopper 30 may be fastened to the inner column 11 by a blind rivet, or the through hole 11a of the inner column 11 may be threaded to fasten the stepped low head bolt 35. You can also do it.

(Energization path)
In this reference example , from the steering wheel 101 to the upper steering shaft 62, the ball bearing 29, the inner column 11, the nut plate 36, the stepped low head bolt 35, the energizing plate 40, the energizing cover 15, the outer column 10, and the tilt bracket. An electric conduction path leading to the vehicle body 100 is secured through 12.

  Of the above energizing paths, the upper steering shaft 62, the ball bearing 29, and the inner column 11 are all made of a metal material having a predetermined electric conductivity, and when they come into contact with each other, the energizing path indicated by the broken line arrow in FIG. Has been secured. Further, the outer column 10 and the tilt bracket 12 are also made of a material having a predetermined electric conductivity, and can be energized by contacting each other. The energization path from the inner column 11 to the outer column 10 will be described below.

  As shown in FIGS. 7 and 8, the upper stopper 30 includes a current-carrying plate 40 made of a plate-shaped metal material having a predetermined electric conductivity. As shown in FIG. 3, the current-carrying plate 40 has an annular portion 40c, the stepped low head bolt 35 is passed through the annular portion 40c, and as shown in FIGS. It is fixed by being sandwiched between the stepped low head bolt 35 and the upper step portion 35b. As shown in FIG. 3, the current-carrying plate 40 has protrusions that protrude forward and backward from the annular portion 40c, and the protrusions are attached to the four locking protrusions 31a provided on the upper surface of the guide member 31. Positioning and detent are achieved by the engagement. The current-carrying plate 40 can be a punched press-molded product of a spring steel plate having elasticity, and as the material of the current-carrying plate 40, a material such as a phosphor bronze plate can be used in addition to the spring steel plate.

  As shown in FIG. 7, a contact portion 40a that is curved obliquely upward and convex upward is formed on the front protrusion of the energization plate 40. The contact portion 40a is elastically deformed and is in contact with the energization cover 15 at a predetermined pressure (contact pressure). With this configuration, when the inner column 11 moves back and forth due to the telescopic adjustment, the inner cover 11 can always contact the current cover 15 by following a slight ups and downs of the current cover 15 and a slight rotation of the inner column 11. Like In addition, since the portion of the contact portion 40a that contacts the energization cover 15 is curved, it is possible to prevent the energization cover 15 and the contact portion 40a from being caught.

  With the above-described configuration, as indicated by the broken line arrow in FIG. 8, an energizing path that is continuous from the inner column 11 to the nut plate 36, the stepped low head bolt 35, the energizing plate 40, and the energizing cover 15 is formed. The energizing cover 15 can be fixed to the outer column 10 by caulking. As a result, an energization path from the inner column 11 to the outer column 10 is secured. For fixing the current-carrying plate 40, various fixing methods such as press-fitting, screw fixing, bolt fixing, brazing, soldering, rivet, bonding, etc. can be adopted in addition to caulking.

( Embodiment )
Next, an embodiment of the present application will be described with reference to FIGS. 9 to 12. The steering device according to the present embodiment is partially configured similarly to the steering device according to the above reference example . Therefore, in the following description, the description overlapping with the reference example will be appropriately omitted. The reference numeral used in the reference example plus 200 is attached to the part of the steering device corresponding to the reference example . For example, the reference numeral "203" is attached to the steering shaft of the embodiment corresponding to the steering shaft 3 of the reference example .

FIG. 9 is a vertical cross-sectional view of the steering device according to the embodiment . The steering device 202 according to the present embodiment is different from the reference example in that it is an electric power steering device (EPS) including a steering assist mechanism 245 that assists the rotation of the steering shaft 203.

  A vehicle front-side end portion of the outer column 210 forms a diametrically enlarged portion 210a diametrically outwardly diametrically enlarged. A first housing 243, which has a substantially annular shape and accommodates the vehicle rear side portion of the steering assist mechanism 245 together with the enlarged diameter portion 210a, is fixed to the vehicle front side of the enlarged diameter portion 210a. A second housing 244, which has a substantially annular shape and accommodates the vehicle front side portion of the steering assist mechanism 245, is fixed between the first housing 243 and the first housing 243 on the vehicle front side. ing.

  A ball bearing 227 is fitted in a radially inner portion of the first housing 243. In addition, a ball bearing 241 is fitted in a radially inner portion of the second housing 244. The ball bearing 227 and the ball bearing 241 rotatably support an output shaft 248 connected to the vehicle front side of the lower shaft 261 via a torsion bar 247.

  The second housing 244 has a pivot boss 222 formed so as to project toward the vehicle front side. The pivot boss 222 is used to attach the steering device 202 to the vehicle body so that the tilt can be adjusted.

A guide groove 225 extending in the axial direction is formed in the upper portion of the outer column 210. Different from the guide groove 25 of the reference example , the guide groove 225 is partially covered with an energization cover 215 formed integrally with the outer column 210. The energization plate 215 attached to the upper stopper 230 contacts the energization cover 215.

  FIG. 10 is a partially enlarged view of the vertical cross section shown in FIG. The cross section within the movable range in the axial direction of the upper stopper 230 is shown enlarged.

  An opening 242 penetrating in the radial direction is formed in a portion of the outer column 210 on the vehicle front side of the energization cover 215. The opening 242 is used to attach the upper stopper 230 and the energizing plate 240 to the inner column 211 in a state where the inner column 211 is moved to the vehicle front side.

  The current-carrying plate 240 is in contact with the current-carrying cover 215 at two locations, a contact portion 240a formed on the vehicle front side and a contact portion (second contact portion) 240b formed on the vehicle rear side. Each of the contact portions 240a and 240b is curved so as to rise toward the energization cover 215 side and be convex toward the energization cover 215 side. Further, the contact portions 240a and 240b are both elastically deformed and contact the energization cover 215 with a predetermined contact pressure.

  The energization plate 240 contacts the energization cover 215 at least at the second contact portion 240b even when the energization plate 240 moves to the adjustment end on the vehicle front side in the telescopic adjustment range TAf for the vehicle front. Therefore, the opening 242 is arranged so as to be located on the vehicle front side with respect to the second contact portion 240b of the energizing plate 240 when the steering device 202 is adjusted to the most vehicle front side in the telescopic adjustment range TAf. .. As a result, a new energization path from the inner column 211 to the outer column 210 can be secured over the entire telescopic adjustment range TA.

In the embodiment , the energization cover 215 formed integrally with the outer column 210 has at least the axial range (the range indicated by reference A in FIG. 10) of the fastening portion (the part indicated by reference numeral 300 in FIG. 10) of the outer column 210. Exists in the part. The presence of the energizing cover 215 in the above range can secure the circumferential rigidity of the tightening portion 300 of the outer column 210, and the tightening mechanism can secure the outer column 210 via the pair of left and right side plates 272, 273 of the tilt bracket 212. Even if the tightening portion 300 is tightened, the tightening portion 300 of the outer column 210 is not excessively bent, and a reaction force against the tightening is generated. Therefore, a tightening force is generated between the tightening portion 300 of the outer column 210 and the fixed cam, and between the tightening portion 300 of the outer column 210 and the nut (see the nut 89 in FIG. 6) to tighten the outer column 210. The side plates 272, 273, the friction plates 285, and the intermediate friction plates (see the intermediate friction plate 86 of FIG. 6) existing between the portion 300 and the fixed cam and between the tightening portion 300 and the nut of the outer column 210, and their respective counterparts. A sufficient frictional force can be generated between the members. With such a configuration, the tilt holding force and the telescopic holding force of the steering device 202 can be reinforced.

In the embodiment , the torque when the steering shaft 203 is twisted with the key lock bar extended is transmitted to the outer column 210 via the inner column 211 and the upper stopper 230. In the present embodiment, since the energizing cover 215 is integrally formed with the outer column 210 on the radially outer side within the range in which the upper stopper 230 moves within the telescopic adjustment range, the strength of the outer column 210 increases and the torque The strength against is secured.

  FIG. 11 is a cross-sectional view showing a cross section taken along line XI-XI shown in FIGS. 9 and 10. A cross section taken perpendicularly to the axial direction of the steering device 202 at the position of the upper stopper 230 is shown.

  The energizing cover 215 is formed integrally with the left and right guide walls 223 and 224 extending from the upper portion of the outer column 210 in the rising axial direction. The lower surface of the energizing cover 215, that is, the surface of the energizing cover 215 on the inner column 211 side is formed in a flat shape. The upper surface of the energization cover 215, that is, the surface of the energization cover 215 opposite to the inner column 211 has a curved surface that is convex upward when viewed in the axial direction.

  FIG. 12 is a partially enlarged view of FIG. The members around the outer column 210 are omitted, and the outer column 210 and the members inside thereof in the radial direction are shown enlarged.

Similarly to the reference example , the energization plate 240 has the stepped low head bolt 235 passed through the annular portion 240c, and is sandwiched and fixed between the upper step portion 235b of the stepped low head bolt 235 and the guide member 231.

According to the embodiment described above, as in the reference example , a new energization path from the steering wheel to the vehicle body can be secured.

  It should be noted that the above specific embodiments have been described in order to facilitate understanding of the present invention, and the present invention is not limited to these.

For example, the current path of the reference example is an application of the present invention to a rack assist type electric power steering system is applicable such a column assist type electric power also of course to such a steering apparatus of the embodiment. On the contrary, the energization path of the embodiment can be applied to the rack assist type electric power steering device.

  Further, the specific configurations of the steering column, the tilt/telescopic adjustment mechanism, the upper stoppers 30, 230, etc. can be appropriately changed without departing from the spirit of the present invention.

  For example, the shapes of the current-carrying plates 40 and 240 are not limited to those in the above-described embodiment, and any shape may be used as long as it contacts the current-carrying covers 15 and 215 with a predetermined pressure (contact pressure) by elastic deformation. Good. For example, the contact portions 40a, 240a, 240b do not necessarily have to be one or two as in the above-described embodiment, and three or more contact portions may be formed. The present invention is not limited to the embodiment, and instead of the curved portion that is convex toward the current-carrying covers 15 and 215, a hemispherical portion that projects toward the current-carrying covers 15 and 215 may be formed. Further, a plurality of contact portions 40a, 240a, 240b may be formed in the circumferential direction so as to be separated from each other, and the energization path may be made more reliable. Further, the contact portions 40a, 240a, 240b may be arranged only on the vehicle rear side of the guide members 31, 231.

  The energizing plates 40 and 240 may be arranged so as to secure an energizing path from the inner columns 11 and 211 to the energizing covers 15 and 215. For example, the energizing plates 40 and 240 are arranged so as to directly contact the inner columns 11 and 211. You may. In that case, it is not necessary that the fixture for attaching the guide members 31, 231 to the inner columns 11, 211 have conductivity.

DESCRIPTION OF SYMBOLS 1 Steering mechanism 2,202 Steering device 3,203 Steering shaft 10,210 Outer column 210a Expanded diameter part 11,211 Inner column 11a Through hole 12,212 Tilt bracket 13,213 Inner peripheral surface 15,215 Conductive cover 21 Collar 22, 222 Pivot boss 22a, 222a Boss hole 23, 24, 223, 224 Guide wall 25, 225 Guide groove 25a, 25b Inner surface 26 Slit 27, 227 Ball bearing 28, 228 Through hole 29, 229 Ball bearing 30, 230 Upper stopper 31, 231 Guide member 31a Locking projection 32, 232 Stopper base 32a Through hole 35, 235 Stepped low head bolt 35a Screw shaft 35b, 235b Upper stepped portion 36, 236 Nut plate 36a Boss portion 36b Upper surface 36c Screw hole 40, 240 Conductive plate 40a , 240a, 240b Contact part 40c, 240c Annular part 241 Ball bearing 242 Opening part 243 First housing 244 Second housing 245 Steering assist mechanism 247 Torsion bar 248 Output shaft 50 Lower stopper 51,251 Resin pin 52,252 Buffer holding Part 53, 253 Buffer block 54 Locking arm 61, 261 Lower steering shaft 61a Male spline 61b Serration 62, 262 Upper steering shaft 62a, 262a Female spline 62b Serration 71, 271 Upper plate 71a Bolt hole 71b, 71c Locking hole 72, 272 Left side plate 72a Tilt adjustment long hole 73, 273 Right side plate 73a Tilt adjustment long hole 80 Tightening mechanism 81 Tightening bolt 81a Male screw 82 Operation lever 83 Movable cam 84 Fixed cam 85, 285 Friction plate 85a, 285a Long hole part 86 Intermediate friction plates 86a, 86b End plate portion 86c Connecting plate portion 87 Pressing plate 88 Thrust bearing 89 Nuts 91, 92 Hook portion 93 Coil spring 95 Coil spring 100 Car body 101 Steering wheel 102 Intermediate shaft 103 Steering gear 104 Electric assist mechanism 105 Tie rod 300 tightening section

Claims (6)

A steering shaft that can expand and contract in the axial direction,
A steering column that includes an outer column and an inner column that are fitted to enable relative movement in the axial direction, and that rotatably supports the steering shaft,
An engaging member fixed to the inner column,
The outer column accommodates the engagement member, prevents rotation of the inner column via the engagement member, extends axially, and guides axial movement of the inner column; A pair of guide walls projecting outward in the radial direction on both the left and right sides of the guide groove and extending in the central axis direction, and a telescopic member arranged at the end of the guide groove and abutting against the engaging member toward the vehicle rear side of the inner column. A vehicle rear side portion that defines an adjustment range, and a tightening portion that tightens the inner column ,
The guide groove is integrally formed with the pair of guide walls, and has a bottom portion facing the engaging member ,
The outer column is an integrally molded product including the guide groove, the vehicle rear side portion, and the bottom portion,
A steering device in which the guide groove and the bottom portion are present at least in an axial range of the tightening portion . A steering shaft that can expand and contract in the axial direction,
A steering column that includes an outer column and an inner column that are fitted to enable relative movement in the axial direction, and that rotatably supports the steering shaft,
An engaging member fixed to the inner column,
The outer column accommodates the engagement member, prevents rotation of the inner column via the engagement member, extends axially, and guides axial movement of the inner column; A pair of guide walls projecting outward in the radial direction on both the left and right sides of the guide groove and extending in the central axis direction, and a telescopic member arranged at the end of the guide groove and abutting against the engaging member toward the vehicle rear side of the inner column. A vehicle rear side portion that defines an adjustment range, and a tightening portion that tightens the inner column ,
The guide groove is formed integrally with the pair of guide walls, and has a bottom portion facing the engaging member ,
The outer column is an integrally molded product including a diameter-enlarged portion that accommodates a steering assist mechanism that assists rotation of the steering shaft, the guide groove, the vehicle rear side portion, and the bottom portion,
A steering device in which the guide groove and the bottom portion are present at least in an axial range of the tightening portion . The guide groove is capable of inserting the engaging member,
The steering device according to claim 1 or 2 , wherein the guide groove is located on the vehicle front side of the engagement member when the inner column is moved to the most vehicle front side in telescopic adjustment. The steering device according to claim 3 , wherein the guide groove is located on the vehicle rear side of the engagement member when the inner column moves to the frontmost side of the vehicle due to a secondary collision. The engaging member has a conductive plate having an electrically conductive plate integrally provided with an elastic portion that electrically contacts the bottom portion,
The outer column constitutes a part of a current-carrying path leading to the vehicle body,
The steering device according to any one of claims 1 to 4 , wherein the inner column and the outer column are configured to be capable of conducting electricity through the engaging member and the energizing plate. The steering device according to any one of claims 1 to 5 , wherein the engagement member faces the bottom portion in a telescopic adjustment range.

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