JP2000095119A - Steering system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering system that allows installation of a heat insulator at low costs. SOLUTION: A heat insulator 60 at its assembled state is provided with a pressure portion that presses a column hole cover 42. The pressure portion 86 bites in the column hole cover 42 against its elastic force. Compared with the case where the press portion 86 is brought into contact with the column hole cover 42, this may increase the friction force between the column hole cover 42 and the press portion 86, thus holding the press portion 86 to the column hole cover 42 securely. As a result, the heat insulator 60 can be stabilized even if there is one position that should be tightened and fixed with the fixation bolt 72.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering device for steering a vehicle.

[0002]

2. Description of the Related Art A steering device, which is a steering device for a vehicle, generally includes a steering wheel having a ring shape as a whole, and one end of a steering shaft is connected to an axis of the steering wheel. .
The steering shaft is inserted into a cylindrical column tube, and penetrates a partition that separates the interior of the vehicle from the engine room. On the engine room side of the bulkhead,
Furthermore, it is covered with a column hole cover. The column hole cover is connected to a steering gear housing that houses a steering gear including a rack bar, a pinion gear, and the like, and a pinion gear in the steering gear housing is integrally formed at an end of the steering shaft on the engine room side. Are linked. This pinion gear meshes with a rack bar elongated in the vehicle width direction, and the end of the rack bar is connected to wheels via a link mechanism including various links such as tie rods and knuckle arms. Have been. When the pinion gear rotates with the rotation of the steering wheel and the rack bar displaces along its own longitudinal direction, the link mechanism operates the wheels according to the amount of displacement and changes the direction of the wheel axis. I have.

There is also a so-called power steering device in which a hydraulic device is provided in the above-mentioned steering device, the displacement of the rack bar is assisted by hydraulic pressure during the rotation operation of the steering wheel, and the operation force required for the rotation operation of the steering wheel is reduced. Generally applied.

By the way, an exhaust pipe for sending out exhaust gas of the engine is installed near the engine room side portion of such a steering device, and when the engine is operating, the exhaust pipe extends from the outer peripheral portion of the exhaust pipe. High temperature heat is dissipating. Since the heat radiated from the exhaust pipe heats the steering gear and the packing provided at the connecting portion of the oil feed pipe for power steering, a plate is provided between the exhaust pipe and the column hole cover and the steering gear housing. A heat insulator (heat insulating material) in a shape of is arranged.

[0005]

Here, fastening bolts usually penetrate at two or more places in the above-mentioned heat insulator, and fastening bolts are screwed into female screw portions formed in the steering gear housing and the column hole cover. Then, the heat insulator is attached by tightening the heat insulator with the fastening bolt and the steering gear housing and the column hole cover.

However, the configuration in which two or more locations are fastened and fixed with fastening bolts as described above has the disadvantage that the number of fastening steps is large and the cost is increased.

An object of the present invention is to provide a steering apparatus to which a heat insulator can be attached at a low cost in consideration of the above fact.

[0008]

According to a first aspect of the present invention, there is provided a steering system for converting the rotation of the steering shaft into a movement in a direction for changing the direction of the axis of a wheel by a steering gear connected to the steering shaft. A steering gear housing that houses the steering gear, a column hole cover that covers the steering shaft and is connected to the steering housing, a heat source near the steering gear housing and the column hole cover, and the column. A heat insulator provided between the hole cover and the steering gear housing, for interrupting or reducing conduction of heat from the heat source to the steering gear housing and the column hole cover; and And a fixed portion fixed to one of the gear housing and the column hole cover, and abuts against the other of the steering gear housing and the column hole cover, and presses the other one in a fixed state of the fixed portion. And a pressing portion supported by the one or the other by friction between the heat insulator and the other.

According to the steering apparatus having the above-described structure, heat from a heat source such as an exhaust pipe provided near the steering gear housing and the column hole cover is cut off by the heat insulator. For this reason, the heat influence of the heat source on the steering gear housing, the column hole cover, and the connection portion with the members (for example, the piping of the steering oil in the so-called power steering device) connected thereto is reduced or prevented.

Here, the fixing portion of the heat insulator is fixed to one of the steering gear housing and the column hole cover by fixing means including fastening means such as bolts. In the fixed state of the fixed portion, the pressing portion that abuts on the other one of the steering gear housing and the column hole cover presses the other one, and in this pressed state, a pressure is generated between the pressing portion and the other one. The pressing portion is supported by the other one due to the friction. As described above, in the present invention, the fixing portion may be basically provided at one place, and the number of steps of the fixing step such as fastening can be reduced.

According to a second aspect of the present invention, in the steering device according to the first aspect, any one of the steering gear housing and the column hole cover corresponds to a connecting portion between the steering gear housing and the column hole cover. A tubular inner tubular portion provided on one side,
The inner cylindrical portion is provided on one of the column hole covers corresponding to the inner cylindrical portion, and covers the outer peripheral portion of the inner cylindrical portion when the steering gear housing is connected to the column hole cover. A tubular outer tubular portion fitted to the outer tubular portion, and the pressing portion presses the outer tubular portion from the outside, and sandwiches the outer tubular portion with the inner tubular portion, I have.

According to the steering device having the above structure, the inner cylindrical portion provided on one of the steering gear housing and the column hole cover is fitted so as to enter the inside of the outer cylindrical portion provided on the other. This connects the steering gear housing and the column hole cover.

Further, when the heat insulator is attached in this connected state, the pressing portion presses the outer cylindrical portion, and the pressing portion is supported by the outer cylindrical portion due to friction between the pressing portion and the outer peripheral portion of the outer cylindrical portion. However, due to the pressing force of the pressing portion at this time and the pressing reaction force from the inner cylindrical portion when the outer cylindrical portion receiving the pressing force presses the outer peripheral portion of the inner cylindrical portion, the outer cylindrical portion is pinched from inside and outside. Is done. Thereby, the relative displacement of the outer cylinder with respect to the inner cylinder is limited, and the above-described connected state is maintained.

[0014] The present invention basically has a configuration in which the outer cylindrical portion is sandwiched between the inner cylindrical portion and the pressing portion of the heat insulator. The following configuration can be cited as a configuration for maintaining the configuration more reliably.

That is, as a configuration having the above-mentioned effect, for example, the outer cylinder portion moving direction in a direction of releasing the engagement with the inner cylinder portion rather than the pressing portion in a state of being pressed on the outer cylinder portion. A contact portion that can be brought into contact with the pressing portion on the opposite side to the outer cylindrical portion is provided on the outer peripheral portion of the outer cylindrical portion.

In the case of such a configuration, the direction of releasing the fitting with the inner cylindrical portion (for example, one axial direction of the outer cylindrical portion)
When the outer cylindrical portion is to be moved relative to the inner cylindrical portion, the contact portion formed on the outer peripheral portion of the outer cylindrical portion tends to move accordingly, but the contact portion is moved in the moving direction. Is in contact with the pressing portion pressing the outer peripheral portion of the outer cylindrical portion in the opposite direction, the movement of the contact portion is limited by the pressing portion,
Indirectly, the movement of the outer cylindrical portion is restricted by the contact portion. Thereby, the connection state between the inner cylindrical portion and the outer cylindrical portion can be maintained more reliably.

In the contact portion having the above structure, a protrusion or the like may be formed in advance on the outer peripheral portion of the outer cylindrical portion, and the outer peripheral portion of the protrusion may be used as the contact portion. An elastic material (for example, a rubber material or a soft synthetic resin material) capable of elastically deforming a contact portion with the pressing portion by a pressing force from the pressing portion.
The inner peripheral portion of the concave portion that is opened toward the outside in the radial direction of the outer cylindrical portion may be used as the contact portion by being elastically deformed by the pressing force of the pressing portion.

According to a third aspect of the present invention, in the steering device according to the second aspect, the outer cylindrical portion is provided on the column hole cover, and the column hole cover including the outer cylindrical portion is provided on the pressing portion. It is characterized by being formed of an elastic member which can be elastically deformed by a pressing force.

According to the steering device having the above structure, the column hole cover is elastically deformable by the pressing force of the pressing portion (for example, rubber or soft synthetic resin).
The outer cylindrical portion provided on the column hole cover is fitted so as to cover the outer peripheral portion of the inner cylindrical portion provided on the steering gear housing.

In this state, when the outer peripheral portion of the outer cylindrical portion provided on the column hole cover is pressed by the pressing portion of the heat insulator, the outer peripheral portion of the outer cylindrical portion is elastically deformed by the pressing force, and the outer cylindrical portion is radially deformed. A concave portion opened outward is formed, and the pressing portion enters the concave portion. In this state,
Not only is the outer cylindrical portion (column hole cover) sandwiched by the inner cylindrical portion (steering gear housing) and the pressing portion, but also the inner circumference of a concave portion formed on the outer peripheral portion of the outer cylindrical portion by the pressing force from the pressing portion. The portion of the portion opposite to the moving direction of the outer cylindrical portion in the direction away from the inner cylindrical portion (that is, the moving direction of the column hole cover in the direction away from the steering gear housing) abuts on the pressing portion, and The movement of the outer cylinder in the direction away from the cylinder is restricted by the pressing portion. For this reason, the connection state between the column hole cover and the steering gear housing can be maintained more reliably.

Further, in the present invention, since the column hole cover is formed of the elastic member as described above, the concave portion is formed by the pressing force of the pressing portion without previously forming the concave portion into which the pressing portion enters. For this reason, the molding of the column hole cover is facilitated, which contributes to cost reduction. Furthermore, by forming the column hole cover with an elastic member, wear or rust at the contact portion with the pressing portion due to vibration or the like during running of the vehicle, or
No abnormal noise is generated.

[0022]

FIG. 2 is a perspective view showing a main part of a steering device 10 according to an embodiment of the present invention, and FIG. 1 is a front view of the steering device 10. I have. FIG. 3 is a cross-sectional view showing an internal structure of a main part of the steering device 10 according to one embodiment of the present invention.

As shown in FIGS. 1 to 3, the steering device 10 includes a steering gear box 12. The steering gear box 12 has a tubular steering gear housing 14 elongated in substantially the left-right direction of the vehicle (the arrow LF in FIGS. 1 and 2 and the opposite direction).
It has. A rack guide 16 is housed inside the steering gear housing 14. A part of the end face of the rack guide 16 is formed with a concave portion 18 having a substantially semicircular cross section in a longitudinal direction substantially along the vehicle left-right direction (the depth direction and the front direction in FIG. 3), and a rack bar 20 serving as a steering gear. Are slidably fitted in the vehicle left-right direction along the concave portion 18. The rack guide 16 is urged toward the opening direction of the concave portion 18 by urging means such as a leaf spring (not shown), and presses the rack bar 20 against a pinion gear 24 serving as a steering gear described later.

Tie rods are attached to both ends of the rack bar 20 in the longitudinal direction. The tie rods are connected to knuckle arms (all without reference numerals are omitted) supporting the front wheels (wheels) of the vehicle via the tie rods. ing. The opposite side of the recess 18 of the rack bar 20 is cut in a plane, and a gear 22 is formed along the longitudinal direction of the rack bar 20. A pinion gear 24 whose axial direction intersects the longitudinal direction of the rack bar 20 meshes with the gear 22 of the rack bar 20. The pinion gear 24 is rotatably supported inside the rack guide 16. When the pinion gear 24 rotates around its own axis, the rack bar 20 meshing with the pinion gear 24 slides along its own longitudinal direction.

As shown in FIG. 3, a torsion bar 26 is arranged coaxially with the pinion gear 24 at one axial end of the pinion gear 24. A steering shaft 28 is formed at one end of the torsion bar 26 in the axial direction, and is fitted to the pinion gear 24 by knurling. Thus, the pinion gear 24 and the torsion bar 26 are integrated. Torsion bar 26
Is coaxially fixed to one end of a gear-side shaft 30 constituting the steering shaft 28. The other end of the gear-side shaft 30 protrudes toward the cabin 34 through a partition 36 that separates the engine room 32 of the vehicle from the cabin 34, and further has a distal end through a universal joint 38. Also, it is connected to one longitudinal end of a wheel-side shaft 40 constituting the steering shaft 28. The other end in the longitudinal direction of the wheel side shaft 40 is coaxially fixed to a hub of the steering wheel which is formed in a ring shape as a whole.

As shown in FIG. 3, around the portion between the partition 36 of the gear-side shaft 30 and the steering gear box 12, a column hole which is entirely cylindrical and bellows bent. A cover 42 is provided. The column hole cover 42 is formed of an elastic member such as a rubber material or a synthetic resin material having the same elasticity as the rubber material.
One cylindrical opening end 44 is fixed to the partition wall 36, and the other cylindrical opening end 46 as an outer cylindrical portion is a cylindrical portion 4 as a cylindrical inner cylindrical portion formed in the steering gear box 12.
8 is fitted into the cylindrical portion 48 in a state of covering the outer periphery.
As shown in FIG. 3, a ring-shaped flange portion 50 extends from the outer peripheral portion of the cylindrical portion 48 and has a cylindrical open end 46.
Is engaged with the inner peripheral portion of the. Thus, the steering gear box 12 and the column hole cover 42 are substantially integrated.

Further, as shown in FIG. 3, the steering device 10 includes a control valve shaft 52 having one end fixed to the gear-side shaft 30 described above. The control valve shaft 52 is entirely cylindrical and has the torsion bar 2 described above inside.
When the torsion bar 26 is twisted, the control valve shaft 52 can rotate relative to the torsion bar 26 by the twist angle of the torsion bar 26. Inside the steering gear box 12 and around the control valve shaft 52, a rotary valve 54 is arranged coaxially with the control valve shaft 52. The control valve shaft 52 has a plurality of through holes 56 penetrating between the inner peripheral portion and the outer peripheral portion.

As shown in FIG. 3, the steering gear box 12 is formed with a plurality of through holes 58 communicating the inside and the outside thereof, and communicates with the through holes 56 of the rotary valve 54. The through-hole 56 is provided inside a reservoir tank for storing steering oil via a hose or a power cylinder (not shown), in which a power piston coaxially and integrally connected to a rack bar is housed. Communicating. That is, the steering device 10 is a so-called “power steering device” that assists the steering force with the hydraulic pressure of the steering oil.

As shown in FIGS. 1 and 2, the steering apparatus 10 includes a heat insulator 60.

The heat insulator 60 is formed by press-forming a plated steel plate, and has a main body 62 corresponding to a portion of the steering gear box 12 in which the rack bar 20 is accommodated. The main body 62 has a flat plate shape as a whole, and a fixing portion 66 having a through hole 64 is provided in a part thereof. The through hole 64 of the fixing portion 66 is formed corresponding to the screw hole 70 of the fixed portion 68 formed on the outer peripheral portion of the steering gear box 12, and the fixing bolt 72 penetrating the fixing portion 66 is formed with the screw hole 70. The main body 62 of the heat insulator 60 is fixed to the steering gear housing 14 by being screwed and fastened.

From one end in the width direction of the main body 62, horizontal wall portions 74 and 76 extend obliquely downward, and extend above a portion of the steering gear housing 14 in which the rack bar 20 is accommodated (in a direction indicated by an arrow UP in FIG. 2). Side). Also,
A vertical wall portion 78 extends obliquely upward from one end in the longitudinal direction of the main body 62. On the other hand, a vertical wall portion 80 extends obliquely upward from the other end in the longitudinal direction of the main body 62, and is substantially on the left side of the portion of the steering gear housing 14 in which the control valve shaft 52 is accommodated (see FIG. 2 (in the direction of the arrow LF). An exhaust pipe (not shown) serving as a heat source passes between the vertical wall portion 78 and the vertical wall portion 80. The exhaust pipe is a pipe for supplying high-temperature exhaust gas from an engine to an exhaust port, and radiates heat from an outer peripheral portion by being heated by the exhaust gas.

A vertical wall portion 82 continuously extends from one end in the width direction of the vertical wall portion 80 and one end in the longitudinal direction of the horizontal wall portion 74.
4 covers substantially the front side of the vehicle (the direction of arrow FR in FIGS. 1 and 2).

Further, a neck portion 84 extends from the upper end of the vertical wall portion 80 in a direction approaching the cylindrical opening end 46 of the column hole cover 42. The distal end of the neck portion 84 is once bent substantially toward the upper side of the vehicle, and then the cylindrical open end 46 is bent.
The portion bent toward the upper side of the vehicle is formed as a pressing portion 86 at the cylindrical open end 46.
And presses the cylindrical opening end 46.

Here, as shown in FIG.
6 is curved so as to protrude toward the cylindrical opening end 46 in a plan view, and further, as shown in FIG.
The horizontal dimension L1 from the center of No. 4 to the pressing portion 86 is:
It is slightly longer than the horizontal dimension L2 from the center of the screw hole 70 to the portion where the pressing portion 86 of the cylindrical opening end 46 abuts. Therefore, when the main body 62 is fixed to the steering gear housing 14 by the fixing bolt 72 in a state where the through hole 64 and the screw hole 70 are coaxial, the pressing part 86
6 is elastically deformed so that the pressing portion 86 bites into the cylindrical opening end 46. As a result, a concave portion 90 that opens outward in the radial direction is formed at the cylindrical opening end 46.

Further, as shown in FIGS. 1 and 2,
A vertical wall portion 88 that extends along the curvature of the column hole cover 42 extends from the upper end of the horizontal wall portion 74, and covers a substantially lower half of the column hole cover 42 on the substantially left side of the vehicle.

Next, the operation and effect of this embodiment will be described.

In the present steering apparatus 10, a heat insulator 60 is provided on the column hole cover 42, and the heat insulator 60 is provided on the substantially upper side of the vehicle in which the rack bar 20 of the steering gear housing 14 is accommodated. The portion that accommodates the steering shaft 28 and the substantially vehicle left side of the column hole cover 42 are covered. For this reason,
An exhaust pipe (heat source) that passes substantially above the portion of the steering gear housing 14 in which the rack bar 20 is accommodated and on the substantially left side of the portion of the steering gear housing 14 in which the steering shaft 28 is accommodated.
Even if heat is dissipated from the steering gear housing 1, the dissipated heat is blocked by the heat insulator 60.
4 or the propagation of heat to the column hole cover 42 is reduced or prevented. Thereby, the steering gear box 1
The deterioration of a member made of a synthetic resin material or a rubber material such as an oil seal provided at a connection portion with the steering oil supply hose 2 can be reduced or prevented.

The heat insulator 60 having the above operation is fixed to the steering gear housing 14 as follows.

As shown by the two-dot chain line in FIG.
The pressing portion 86 is connected to the cylindrical opening end 46 (the column hole cover 4).
With respect to the predetermined contact portion of 2), it is disposed so as to be displaced around the axis C of the through hole 64 of the fixing portion 66 and the screw hole 70 (not shown in FIG. 5) of the fixed portion 68, and in this state. The fixing bolt 72 is temporarily tightened so that the heat insulator 60 can rotate around the axis C. After temporarily fixing the fixing bolt 72, the fixing bolt 72 is fully tightened (that is, the heat insulator 60 is connected to the steering gear housing 14).
The heat insulator 60 is rotationally displaced around the axis C in the direction of the arrow A while being fixed. As a result, the pressing portion 86 is moved to the cylindrical opening end 46 (column hole cover 42).
Is pressed to elastically deform the cylindrical opening end 46, and the pressing portion 86
Bites into the cylindrical opening end 46 (the state shown in FIG. 4). In this state, since the pressing portion 86 presses the cylindrical opening end 46 against the elastic force of the cylindrical opening end 46, the cylindrical opening end 4 is simply formed.
6, the frictional force between the cylindrical opening end 46 and the pressing portion 86 is larger than when the contacting portion 6 contacts the pressing portion 86, and the pressing portion 86 (heat insulator 60) is held by the cylindrical opening end 46. Therefore, even if only one portion is fixed and fixed by the fixing bolt 72, the heat insulator 60 can be stabilized, and the heat insulator 60 can be attached at a low cost.

Further, as shown in FIG.
Presses the cylindrical opening end 46, the cylindrical opening end 46
The pressing portion 86 indirectly presses the cylindrical portion 48 of the steering gear housing 14 via the, and the pressing reaction force from the cylindrical portion 48 presses the cylindrical opening end 46 toward the pressing portion 86. The cylindrical opening end 46 is clamped by the pressing force of the pressing portion 86 and the pressing reaction force of the cylindrical portion 48, so that the cylindrical portion 48 of the cylindrical opening end 46 is held.
Can be maintained in a fitted state (connected state).

Further, as described above, when the pressing portion 86 bites into the cylindrical opening end 46 (the column hole cover 42), a concave portion 90 is formed in the cylindrical opening end 46, and an apparent shape is obtained.
The pressing portion 86 enters the inside of the concave portion 90, and the inner peripheral portion of the concave portion 90 contacts the pressing portion 86. A lower inner peripheral portion 92 as a contact portion of the inner peripheral portion of the concave portion is located below the pressing portion 86 and faces the pressing portion 86 along the vertical direction (axial direction of the cylindrical opening end 46). ing. Therefore, even if the column hole cover 42 is to be moved upward with respect to the steering gear housing 14 (that is, if the column hole cover 42 is to be removed from the steering gear housing 14), the lower inner peripheral portion 92 is pressed by the pressing portion. Since the pressing member 86 is in contact, the upward movement of the lower inner peripheral portion 92, that is, the upward movement of the column hole cover 42 is restricted or prevented by the pressing portion 86. Thus, in this sense, the fitted state (connected state) can be effectively maintained.

That is, in this embodiment, since the flange portion 50 formed on the outer peripheral portion of the cylindrical portion 48 is engaged with the inner peripheral portion of the cylindrical opening end 46, the steering gear box 12 and the column hole Although the cover 42 is connected, the pressing portion 86 is further cut into the cylindrical opening end 46 (the column hole cover 42), so that the pressing force between the pressing portion 86 and the cylindrical portion 48 and the pressing portion 86 are cylindrical. The fitting of the pressing portion 86 with the concave portion 90 formed by cutting into and entering the opening end 46 makes it possible to more reliably maintain the connection state of the column hole cover 42 to the steering gear housing 14. Therefore, the steering gear housing 14 of the column hole cover 42 due to vibration or the like during running of the vehicle
Can be prevented more reliably.

As described above, the column hole cover 4
2 is made of a rubber material or a soft synthetic resin material, and the concave portion 90 is formed on the outer peripheral portion of the cylindrical opening end 46 by the pressing force from the pressing portion 86. Therefore, the recess 90
Need not be formed in advance at the cylindrical opening end 46, and the column hole cover 42 can be easily formed.

Further, by forming the column hole cover 42 from a rubber material or a soft synthetic resin material, the pressing portion 86 is formed.
Abrasion due to vibration or the like at the time of running of the vehicle, rust caused by the abrasion, and generation of abnormal noise at the time of friction can be prevented.

In the present embodiment, the pressing portion 86 is formed by bending the heat insulator 60 as a result. However, the pressing portion 86 corresponding to the pressing portion 86 is formed from a part of the heat insulator 60. The portion may be formed to protrude.

Further, in the present embodiment, the pressing portion 86 is configured to bite into the column hole cover 42.
From the viewpoint of the present invention described in claim 1 or claim 2, the pressing portion 86 is provided with the column hole cover 4.
A configuration that simply presses in without penetrating into 2 may be used.
That is, when the column hole cover 42 is formed of a hard metal or the like, it is basically difficult to make the pressing portion 86 bite into the column cover 42. However, as in the above-described embodiment, the horizontal dimension L1 from the center of the through hole 64 to the pressing portion 86 is set to be equal to the horizontal dimension from the center of the screw hole 70 to the portion where the pressing portion 86 of the column hole cover 42 contacts. The length is slightly longer than the dimension L2 in the direction, and when the fixing bolt 72 is fully tightened, the pressing part 86 is forcibly rotated and displaced to a predetermined contact part of the other party, so that the pressing part 86 is simply moved to the other party. The frictional force is greater than in the case of contact, and the heat insulator 60 can be stabilized. Incidentally, even when the pressing part 86 of the column hole cover 42 or the like is made of a hard metal or the like, a rubber material or a soft synthetic resin material is fixed to the part where the pressing part 86 makes contact. By doing so, it is possible to make the pressing portion 86 bite like in the present embodiment.

Further, in this embodiment, the pressing portion 86 is cut into the column hole cover 42 to form the concave portion 90, and the lower inner peripheral portion 92 of the concave portion 90 as the contact portion and the pressing portion 90 are vertically moved. Although the upward movement of the column hole cover 42 is restricted or prevented by being opposed along the direction, the configuration of the contact portion is not limited to this, and the pressing portion 86 presses the column cover 42. Pressing part 8 in the state
The lower portion 6 may have a configuration facing the pressing portion 86. That is, a configuration in which the pressing portion 86 does not bite into the column hole cover 42 (that is, a configuration in which the concave portion 90 is not formed).
However, when the column hole cover 42 is formed with a projection or the like protruding outward and the pressing portion 86 presses the column hole cover 42, the projection is formed with the pressing portion 86 below the pressing portion 86. With the opposed configuration, basically the same effect as the configuration in which the pressing portion 86 bites into the column hole cover 42 can be obtained.

Further, in this embodiment, the heat insulator 60 is fixed to the steering gear housing 14 by the fixing bolt 72, and the pressing portion 86 presses the column hole cover 42. The structure which presses the housing 14 may be sufficient.

[0049]

As described above, according to the first aspect of the present invention, the heat insulator can be mounted in a stable state even if only one fixing portion is provided.
The man-hour for the fixing process such as fastening can be reduced.

According to the second aspect of the present invention, the relative displacement of the column hole cover with respect to the steering gear housing can be limited by the clamping force between one of the steering gear housing and the column hole cover and the heat insulator. And the connection state with the column hole cover can be maintained.

Further, according to the present invention, the column hole cover is made of an elastic member, and the column hole cover (outer cylindrical portion) is elastically deformed by the pressing force of the pressing portion of the heat insulator so that the pressing portion becomes the column hole cover. (Outer cylinder)
As a result, the connection between the steering gear housing and the column hole cover can be more reliably maintained, and the space between the pressing portion of the heat insulator and the column hole cover (outer cylindrical portion) due to vibrations during vehicle running, etc. Abrasion, rust resulting therefrom, or abnormal noise caused by friction can be prevented. The relative displacement of the gear housing can be limited, and the connection between the heat insulator and the steering gear housing can be maintained.

[Brief description of the drawings]

FIG. 1 is a front view of a main part of a steering device according to an embodiment of the present invention.

FIG. 2 is a perspective view of a main part of the steering device according to the embodiment of the present invention.

FIG. 3 is a sectional view showing a mechanism of the steering device according to the embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a main part of the steering device according to the embodiment of the present invention.

FIG. 5 is a diagram schematically illustrating a state when a heat insulator is attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Steering device 14 Steering gear housing 20 Rack bar (steering gear) 24 Pinion gear (steering gear) 28 Steering shaft 42 Column hole cover 46 Cylindrical opening end (outer cylindrical part) 48 Cylindrical part (inner cylindrical part) 60 Heat insulator 66 Fixed Part 86 pressing part

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Junichi Tokumoto 1-1-1, Daihatsu-cho, Ikeda-shi, Osaka F-term in Daihatsu Industry Co., Ltd. 3D030 DC01 DC17 DC32 DC33 DC39

Claims (3)

[Claims] 1. A steering device for converting the rotation of the steering shaft into a motion in a direction to change the direction of the axis of a wheel by a steering gear connected to the steering shaft, wherein the steering gear accommodates the steering gear. A housing, a column hole cover which covers the steering shaft and is connected to the steering housing, and is provided between the steering gear housing and the heat source near the column hole cover, and between the column hole cover and the steering gear housing; A heat insulator for blocking or reducing conduction of heat from the heat source to the steering gear housing and the column hole cover, and wherein the steering gear housing and the column hole cover are provided. And a fixed portion fixed to one of the steering gear housing and the other one of the column hole cover, and in a fixed state of the fixed portion, presses one of the other and the other one of the other. And a pressing portion supported by one of the other members due to friction between the steering wheel and the heat insulator. 2. A cylindrical inner cylindrical portion provided on one of the steering gear housing and the column hole cover corresponding to a connecting portion between the steering gear housing and the column hole cover; The steering gear housing and the column hole cover are connected to the inner cylindrical portion so as to cover the outer peripheral portion of the inner cylindrical portion when the steering gear housing and the column hole cover are connected to each other. A cylindrical outer tubular portion, wherein the pressing portion presses the outer tubular portion from the outside, and sandwiches the outer tubular portion with the inner tubular portion. 2. The steering device according to 1. 3. The method according to claim 3, wherein the outer cylindrical portion is provided on the column hole cover, and the column hole cover including the outer cylindrical portion is formed of an elastic member that can be elastically deformed by the pressing force of the pressing portion. The steering device according to claim 2, wherein