JP3342349B2 - Cable steering system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable-type steering device in which a steering wheel and a steering gear box are connected by a cable such as a Bowden cable.

[0002]

2. Description of the Related Art There has been proposed a cable type steering apparatus employing a flexible transmission means such as a Bowden cable instead of a steering shaft connecting a steering wheel and a steering gear box (Japanese Patent Laid-Open No. Hei 8-24).
No. 31). By employing such a cable-type steering device, not only can the position of the steering wheel relative to the position of the steering gear box be freely selected, but also the vibration of the steering gear box is hardly transmitted to the steering wheel.

The Bowden cable is composed of an outer tube and an inner cable. By sliding the inner cable relative to the outer tube, the steering torque input to the steering wheel is reduced. It is designed to be transmitted to the box. When the steering torque is not input to the handle, a predetermined set tension is applied to the inner cable, and the set tension prevents the handle from becoming unnecessarily large.

[0004]

However, if the cable-type steering device is used for a long period of time, it is inevitable that the inner cable made of a twisted metal wire or the like will be stretched. There is a problem that the set tension decreases or disappears and the play of the handle increases.

The present invention has been made in view of the above circumstances, and has as its object to compensate for the extension of an inner member of a cable used in a cable type steering device.

[0006]

According to a first aspect of the present invention, there is provided a driving pulley connected to a steering wheel and a steering gear box for turning wheels. A driven pulley that rotates, and a cable that transmits the rotation of the drive pulley to the driven pulley. The cable has one end supported by a drive pulley housing that houses the drive pulley, and a driven pulley that houses the driven pulley. A cable composed of a pair of outer members whose other ends are supported by the housing, and a pair of inner members which are slidably housed inside these outer members and whose both ends are wound and fixed around a driving pulley and a driven pulley. Slidable on one of the drive pulley housing and the driven pulley housing While being supported, characterized by comprising a single cable holder pair of outer member is fixed, and a spring for biasing the cable holder in the direction to push the outer member from said one housing.

According to the above construction, when the set tension of the inner member is reduced due to the elongation of the inner member due to aging, the cable holder moves by the elastic force of the spring and pushes the outer member out of the housing.
The tension of the inner member is increased by that amount, and the set tension of the inner member is secured.

According to a second aspect of the present invention, a hand
Steering wheel connected to a rotating pulley and wheels
A driven gear connected to the steering gear box and rotating
And a cable that transmits the rotation of the drive pulley to the driven pulley.
This cable accommodates the drive pulley.
One end is supported by the driving pulley housing
The other end of the driven pulley housing
A pair of outer members supporting the
It is slidably stored inside the material and both ends are driven pulleys
And a pair of ins wound and fixed around the driven pulley.
Cable type steering device composed of
, The driving pulley housing and the driven pulley housing
While being slidably supported on one side of the housing,
A cable holder to which a pair of outer members are fixed,
The direction in which the outer member is pushed out of the one housing
A spring that biases the cable holder, a gap is formed between the inner surface of the one housing and the cable holder so that the cable holder can swing, and a tension difference between the pair of inner members causes the cable holder to swing. When the cable swings, the cable holder is engaged with and fixed to the one housing.

According to the above configuration, the inner member is changed with time.
Elongation due to the formation of the inner member causes the set tension of the inner member to decrease.
When it decreases, the spring force of the spring causes the cable holder to
To move and push the outer member out of the housing,
The tension of the inner member increases by that amount,
The set tension of the material is secured. Further, when a steering torque is input to the steering wheel and a tension difference is generated between the pair of inner members, the pair of outer members is pushed and pulled in accordance with the change in the tension, and as a result , the cable holder to which one end of the outer member is fixed swings. The outer member moves and bites into the housing and is immovably fixed to the housing, so that one end of the outer member becomes immovable and transmission of steering torque by the pair of inner members becomes possible.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 5 show an embodiment of the present invention. FIG. 1 is an overall perspective view of a cable type steering device.
FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG. 1, and FIG.
4 is an exploded perspective view of a main part, and FIG.
5 is an enlarged sectional view, and FIG. 6 is an operation explanatory view corresponding to FIG.

As shown in FIG. 1, the steering wheel 1
Drive pulley housing 2 provided in front, steering
Driven pulley housing 4 provided above gear box 3
Are connected by two Bowden cables 5 and 6.
You. From both ends of the steering gear box 3
Tie rod 7 extending in the direction_L, 7_RBut the left and right wheels
W _L, W_RIs connected to a knuckle (not shown)
You.

As shown in FIGS. 2 to 4, a driving pulley 11dr is fixed to a rotating shaft 10dr which is rotatably supported by the driving pulley housing 2 and rotates together with the handle 1. The two Bowden cables 5, 6 are composed of outer tubes 5o, 6o and inner cables 5i, 6i slidably housed therein. One end of each of the inner cables 5i, 6i is wound and fixed a plurality of times around a helical pulley groove formed on the outer periphery of the drive pulley 11dr, and one end of the outer tubes 5o, 6o is connected via a tension adjusting means 12 to the drive pulley housing. 2 supported.

[0014] Tension adjusting means 12, swinging the Sutaida 13 which is slidably supported by the guide grooves 2 ₁ formed on the bottom surface of the driving pulley housing 2, an intermediate portion to the pin 14 formed integrally with the slider 13 freely supported single
As one of the cable holder 15, the guide grooves 2 ₁ is accommodated in a compressed state, the slider 13 driving pulley 1
A spring 16 for urging in a direction away from 1dr. Adjustment screws 17, 17 provided at one end of the pair of outer tubes 5o, 6o are fixed to both ends of the cable holder 11, and the inner cables 5i, 6i housed inside the outer tubes 5o, 6o are the cables. It is wound around the drive pulley 11dr through the holder 15.

A small gap α (see FIG. 2) is formed between both ends of the cable holder 15 and the inner surface of the drive pulley housing 2. When the cable holder 15 slightly swings, the cable holder 15 is moved. Are engaged with the inner surface of the drive pulley housing 2 and are immovably fixed by frictional force. The inner cables 5i, 6i made of metal stranded wires are elastic bodies that expand and contract according to the tension acting on them, and have a spring constant of, for example, 10 kgf / mm.
Is set to The spring constant of the spring 16 is
The value is set to a value (for example, 1 kgf / mm) much smaller than the spring constant of the inner cables 5i and 6i.

As shown in FIGS. 1 and 5, a driven pulley 11dn is fixed to a rotating shaft 10dn rotatably supported by the driven pulley housing 4, and the other ends of the inner cables 5i, 6i are connected to the driven pulley 11dn. The outer ends of the outer tubes 5o and 6o of both Bowden cables 5 and 6 are fixed to the driven pulley housing 4. A pinion 21 is provided at the tip of a rotating shaft 10dn projecting from the driven pulley housing 4 to the inside of the steering gear box 3, and this pinion 21 is attached to a steering rod 22 which is slidably supported in the steering gear box 3 left and right. It is engaged with the formed rack 23.

A power steering motor 24 as power assist means is supported by the driven pulley housing 4, and an output shaft 25 is provided inside the driven pulley housing 4.
Is engaged with a worm wheel 27 provided on the rotating shaft 10dn. Accordingly, the torque of the power steering motor 24 is transmitted to the rotating shaft 10dn via the worm 26 and the worm wheel 27.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

When the rotating shaft 10dr is rotated in the direction A in FIG. 2 by operating the steering wheel 1 to turn the vehicle, the Bowden cable 5, which is wound around the driving pulley 11dr,
The rotation of the driving pulley 11dr is transmitted to the driven pulley 11dn by pulling one inner cable 6i and loosening the other inner cable 5i. As a result, rotates the rotary shaft 10dn shown in FIG. 5, the pinion 21 of the steering gear box 3, the rack 23 and Su-ring wheel via the rod 22 W _L, a W _R is the steering torque is transmitted.

When the steering torque input to the steering wheel 1 is detected by a steering torque sensor (not shown), the electronic control unit calculates the steering torque together with other control signals such as a vehicle speed signal, and, based on the result, calculates the steering torque. Inner cable 5
The steering assist torque generated by the power steering motor 24 is feedback-controlled so that the difference in tension between i and 6i is substantially constant. When the power steering motor 24 generates torque in this way, the rotating shaft 10dn rotates via the worm 26 and the worm wheel 27, and assists the driver in operating the steering wheel 1.

When the steering torque is not input to the steering wheel 1, unnecessary play of the steering wheel 1 can be suppressed by applying a predetermined set tension to the inner cables 5i, 6i of the Bowden cables 5, 6. . In order to apply a predetermined set tension to the inner cables 5i, 6i, the outer tubes 5o connecting the drive pulley housing 2 and the driven pulley housing 4 by rotating the adjusting screws 17, 17 provided at one ends of the outer tubes 5o, 6o. , 6o may be increased. When the total length of the outer tubes 5o, 6o increases, the inner cables 5i, 6i housed therein are elongated, and tensile stress (ie, set tension) is generated.

More specifically, the inner cable 5
Since the spring constant of i, 6i is 10 kgf / mm, in order to apply a set tension of 10 kgf to each inner cable 5i, 6i, each inner cable 5i, 6i
Adjustment screw 1 so that the length of
The outer tubes 5o, 6o may be pushed out of the drive pulley housing 2 by rotating 7, 7. Thus, the outer tubes 5o, 6o are connected to the drive pulley housing 2
When the cable holder 15 is pushed out of the slider 1, the cable holder 15 is moved by the compression force acting on the outer tubes 5 o and 6 o.
The slide 16 slides toward the drive pulley 11dr together with 3, and the spring 16 is compressed. At this time, the resilience of the compressed spring 16 is reduced by the two inner cables 5i, 6
In order to balance with 20kgf which is the sum of the set tension of i,
Spring 16 with a spring constant of 1 kgf / mm is 20 mm
Will shrink.

When the cable type steering device is used for a long period of time, the inner cable 5
The elongation occurs in i and 6i, and the set tension of 10 kgf gradually decreases. And each inner cable 5i, 6
When i increases by 1 mm, the tension adjusting means 12 of this embodiment
When there is no, the set tension disappears. However, in this embodiment, the slider 13 and the cable holder 15 are integrally 1 m by the elastic force of the spring 16 of the tension adjusting means 12 as the inner cables 5i and 6i are extended.
m, and the outer tubes 5o, 6o are pushed out of the drive pulley housing 2 by 1 mm. At this time,
Since the compression amount of the spring 16 is reduced from 20 mm to 19 mm and the resilience is also reduced from 20 kgf to 19 kgf, the set tension of each inner cable 5i, 6i is maintained at 9.5 kgf, which is 0.5 kgf reduced from the initial 10 kgf. . That is, the provision of the tension adjusting means 12 makes it possible to suppress a change in the set tension when the inner cables 5i and 6i are elongated and deformed by 1 mm to only 0.5 kgf.

In FIG. 6, when the handle 1 is operated in the direction of arrow A to generate a difference in tension between the inner cables 5i, 6i, the inner cables 5i, 6 on the side where the tension is increased.
The outer tubes 5o and 6o corresponding to i are pulled in a direction approaching the drive pulley 11dr, and the outer tubes 5o and 6o corresponding to the inner cables 5i and 6i on the side where the tension is reduced are pushed in a direction away from the drive pulley 11dr. Accordingly, the cable holder 15 swings around the pin 14 in the direction of arrow B. When the cable holder 15 swings slightly, the cable holder 15 is immovably fixed at points a and b at the inner surface of the drive pulley housing 2, so that one ends of the outer tubes 5o and 6o become immovable. Therefore, the outer tubes 5o, 6o are prevented from moving together with the movement of the inner cables 5i, 6i, and the rotation of the drive pulley 11dr can be transmitted to the driven pulley 11dn without play, and the occurrence of play causes Deterioration of steering feeling is avoided. Also handle 1
Since the correct tension difference is generated in the inner cables 5i and 6i in accordance with the above operation, when the steering torque is detected based on the tension difference, the detection accuracy can be improved.

Also, utilizing the fact that the position of the slider 13 changes in accordance with the amount of extension of the inner cables 5i and 6i, it is turned on when the position of the slider 13 changes by a predetermined amount.
By providing a switch for controlling the inner cable 5 or by continuously detecting the position of the slider 13,
An alarm can be issued when the elongation amount of i, 6i reaches a predetermined value.

Next, a second embodiment of the present invention will be described with reference to FIGS.

In the second embodiment, the slider 13 and the pin 14 are eliminated from the first embodiment to reduce the number of parts. That is, the driving pulley housing 2 is formed with a partition wall 2 ₂ which partitions the accommodating portion of the drive pulley 11dr, cable holder 15 on the outer side of the partition wall 2 ₂ is slidably supported. Outer tube 5o, cable holder 15 6o is fixed, the spring 1 disposed between the pair of spring seats 2 _3, 2 ₃ provided in the partition wall 2 ₂
It is urged outward at 6,16. Also, between the inner surface of the drive pulley housing 2 and the cable holder 15,
A minute gap α is formed as in the first embodiment, and the cable holder 15 can swing within the range of the gap α.

According to the second embodiment, the direction in which the cable holder 15 urged by the springs 16, 16 pushes the outer tubes 5o, 6o from the drive pulley housing 2 in accordance with the extension of the inner cables 5i, 6i. Therefore, the tension of the inner cables 5i, 6i can be secured by compensating for the expansion of the inner cables 5i, 6i. Further, when the cable holder 15 slightly swings with the operation of the handle 1, the cable holder 15 bites into the inner surface of the drive pulley housing 2 and one end of the outer tubes 5o, 6o becomes immovable. , 6i is prevented from moving together with the movement of the outer tubes 5o, 6o.

Although the embodiments of the present invention have been described in detail, various design changes can be made in the present invention without departing from the gist thereof.

For example, in the embodiment, the tension adjusting means 12 is provided on the drive pulley housing 2 side, but it may be provided on the driven pulley housing 4 side. In the embodiment, the steering device that assists the driver's steering force with the power steering motor 24 has been described. However, the present invention is transmitted via the Bowden cables 5 and 6 without using the power steering motor 24. The present invention can also be applied to a steering device that performs manual steering only with a load. The tension adjusting means 12 not only compensates for a change in set tension due to elongation of the inner cables 5i and 6i, but also compensates for a change in set tension due to thermal expansion of the driving pulley 11dr, the driven pulley 11dn or the inner cables 5i and 6i. Can also.

[0031]

As described above, according to the first and second aspects of the present invention, when the set tension of the inner member is reduced due to the elongation of the inner member due to the aging, the spring force of the spring causes the cable holder to move. Moves and pushes the outer member out of the housing, so that the tension of the inner member is increased by that amount and the set tension of the inner member is secured.

According to the first aspect of the present invention, a pair of
Fixing the outer member to a single cable holder
Can be, According particularly to the second aspect of the present invention, when the steering torque is input handle tension difference occurs pair of inner members, pushed and pulled a pair of outer member according to the variation in tension, as a result Since the cable holder to which one end of the outer member is fixed swings and bites into the housing and is immovably fixed to the housing,
One end of the outer member becomes immovable, and transmission of steering torque by the pair of inner members becomes possible. In this manner, the steering torque input to the steering wheel can be transmitted to the steering gear box without hindrance while compensating for the extension of the inner member and preventing play of the steering wheel.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a cable-type steering device.

FIG. 2 is an enlarged sectional view taken along line 2-2 of FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is an exploded perspective view of a main part.

FIG. 5 is an enlarged sectional view taken along line 5-5 of FIG. 1;

FIG. 6 is an operation explanatory view corresponding to FIG. 2;

FIG. 7 is a view corresponding to FIG. 2 according to a second embodiment.

FIG. 8 corresponds to FIG. 4 according to the embodiment of FIG. 2;

[Explanation of symbols]

Reference Signs List 1 handle 2 drive pulley housing 3 steering gear box 4 driven pulley housing 5 Bowden cable (cable) 5i inner cable (inner member) 5o outer tube (outer member) 6 bowden cable (cable) 6i inner cable (inner member) 6o outer tube (Outer member) 11dr Driving pulley 11dn driven pulley 15 Cable holder 16 Spring W _L wheel W _R wheel α Clearance

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-10-217989 (JP, A) JP-A-8-2431 (JP, A) JP-A-48-58255 (JP, A) JP-A-60-1985 189671 (JP, A) JP-A-9-315318 (JP, A) JP-A-10-109657 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B62D 1/04-1 / 28

Claims (2)

(57) [Claims] 1. A driven pulley (11dn) connected to a handle (1) and rotating, and a driven pulley (11dn) connected to and rotated by a steering gear box (3) for steering wheels (W _L and W _R ). ) And the drive pulley (11dr)
And a cable (5, 6) for transmitting the rotation of the motor to the driven pulley (11dn).
Is a pair of outer members (one end supported by a driven pulley housing (2) housing the driven pulley (11dr) and the other end supported by a driven pulley housing (4) housing the driven pulley (11dn). 5o, 6o)
And a pair of inner members (5i, 6i) which are slidably housed inside these outer members (5o, 6o) and are wound and fixed at both ends to a driving pulley (11dr) and a driven pulley (11dn). In the cable-type steering device thus configured, a single unit in which a pair of outer members (5o, 6o) are fixed while being slidably supported by one of the drive pulley housing (2) and the driven pulley housing (4).
One cable holder (15) and the outer member (5o,
(6) a spring (16) for urging the cable holder (15) in the direction in which the cable is pushed out, and a cable-type steering device. 2. A rotating drive connected to a handle (1).
Steer the dynamic pulley (11dr) and wheels (W _L , W _R )
Connected to the steering gear box (3)
Driven pulley (11dn) and driving pulley (11dr)
Cable for transmitting the rotation of the motor to the driven pulley (11dn)
(5, 6), and this cable (5, 6)
Is a drive pulley housing that houses the drive pulley (11dr)
One end is supported by the jing (2) and the driven pulley
(11dn) in the driven pulley housing (4)
A pair of outer members (5o, 6o) supported at the other end
And the inside of these outer members (5o, 6o)
The drive pulley (11dr)
One fixed around the driven pulley (11dn)
And a pair of inner members (5i, 6i).
In the bull type steering device, the drive pulley housing (2) and the driven pulley housing
Slidably supported by one of the ring (4)
To which a pair of outer members (5o, 6o) are fixed.
Cable holder (15) and the outer member (5o,
6o) Attach the cable holder (15) in the extrusion direction.
A biasing spring (16), and a gap (α) is formed between the inner surface of the one housing (2) and the cable holder (15) so that the cable holder (15) can swing, Due to the tension difference between the pair of inner members (5i, 6i), the cable holder (1
When 5) is swung, characterized in that the cable holder (15) is fixed bite into the housing (2) of the one, cable type steering device.