JP2003276611A - Cable type steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve steering feeling by reducing steering friction torque of a cable type steering device. <P>SOLUTION: In this cable type steering device, a drive pulley 59 connected with a steering handle 11 and rotating, and a driven pulley 60 connected with a rack 85 and a pinion 84 of a steering gearbox and rotating are connected by operation cables 15, 16, and steering torque inputted into the steering handle 11 is transmitted to the steering gearbox. The diameter D1 of the drive pulley 59 is set smaller than the diameter D2 of the driven pulley 60 for reducing the steering friction torque by the frictional force of the operation cables 15, 16 or the frictional force of the steering gearbox to improve return in the neutral position of the steering handle 11, and to reduce a load at the beginning of steering of the steering handle 11. Thereby, steering feeling can be enhanced. <P>COPYRIGHT: (C)2004,JPO

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 handle and a steering gear box are connected by a flexible operating cable such as a Bowden cable.

[0002]

2. Description of the Related Art Such a cable type steering device is
For example, JP-A-2000-25623 and JP-A-10-
It is known from Japanese Patent No. 59197 and Japanese Patent Laid-Open No. 8-2431.

In the conventional cable type steering device, the diameter of the driving pulley and the diameter of the driven pulley are set to be the same, and the torque of the driving pulley connected to the steering wheel is applied to the driven pulley connected to the steering gear box. It was transmitted without increasing or decreasing.

[0004]

By the way, the conventional cable type steering device in which the diameter of the driving pulley and the diameter of the driven pulley are set to be the same has a problem in the steering feeling, and the frictional force of the operation cable and the steering gear box. It has been desired to improve such a problem that the return of the steering wheel to the neutral position is deteriorated due to the frictional force of the steering wheel and the load at the beginning of turning the steering wheel is increased.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to reduce the steering friction torque of a cable type steering device to improve the steering feeling.

[0006]

In order to achieve the above object, according to the invention described in claim 1, a drive pulley which is connected to a steering handle to rotate and a steering gear box which steers wheels are connected. In a cable-type steering device that connects a driven pulley that rotates and is rotated with an operation cable, and transmits the steering torque input to the steering wheel to the steering gear box via the operation cable, the diameter of the drive pulley is greater than the diameter of the driven pulley. A cable type steering device is proposed which is characterized in that

According to the above construction, the diameter of the drive pulley is made smaller than the diameter of the driven pulley, so that the steering friction torque due to the frictional force of the operation cable and the frictional force of the steering gear box can be reduced, and the steering wheel of the steering wheel can be reduced. It is possible to improve the return to the neutral position and reduce the load at the start of turning the steering wheel to improve the steering feeling.

According to the invention described in claim 2,
In addition to the structure of claim 1, there is proposed a cable type steering device characterized in that a tension adjusting mechanism for adjusting the tension of an operation cable is provided adjacent to a driven pulley.

According to the above construction, since the tension adjusting mechanism for adjusting the tension of the operation cable is provided adjacent to the driven pulley, the tension adjusting mechanism is provided on the operation cable more than the case where the tension adjusting mechanism is provided adjacent to the drive pulley. The pressing force of the tension adjusting mechanism required to apply the tension is reduced, and the steering feeling can be improved by minimizing the increase in the frictional force of the operation cable due to the pressing force.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.

1 to 9 show an embodiment of the present invention. FIG. 1 is an overall perspective view of a cable type steering device,
2 is an enlarged sectional view taken along line 2-2 of FIG. 1, and FIG. 3 is 3-3 of FIG.
4 is a perspective view of the steering torque sensor, FIG. 5 is a circuit diagram of a differential transformer of the steering torque sensor, FIG. 6 is an explanatory view of the operation of the steering torque sensor, and FIG. 7 is an enlarged view of line 7-7 in FIG. FIG. 8 is a sectional view, FIG. 8 is a sectional view taken along line 8-8 of FIG. 7, and FIG.

As shown in FIG. 1, a drive pulley casing 12 provided in front of a steering wheel 11 of an automobile.
And a driven pulley casing 14 provided above the steering gear box 13 are connected by two operation cables 15 and 16 made of Bowden cables. The tie rods 17L and 17R extending from the both ends of the steering gear box 13 in the left-right direction of the vehicle body are attached to the left and right wheels W.
It is connected to a knuckle (not shown) that supports L and WR. A steering torque sensor for detecting a steering torque input to the steering handle 11 is built in the drive pulley casing 12, and the driven pulley casing 14 and the driven pulley casing 14 are controlled by a controller 18 to which the detected steering torque is input. The actuator 20 provided in the integrated gear casing 19 operates to assist the driver's steering operation.

As shown in FIG. 2, the drive pulley casing 12 includes a rear housing 21 and a center housing 22.
The front housing 23 is connected with bolts 24, and the front cover 25 is connected to the front surface of the front housing 23 with a bolt (not shown). In the drive pulley casing 12, a bracket 21a provided on the rear housing 21 is fixed to the mounting stay 26 by a pin 27, and a bracket 23a provided on the front housing 23 is fixed to the mounting stay 26 with a bolt 28.

A hollow steering shaft 29 connected to the steering handle 11 is rotatably supported on the rear housing 21 by two ball bearings 30 and 31. A metal pulley boss 33 is fixed to the outer circumference of a hollow pulley shaft 32 arranged coaxially with the steering wheel 11. The drive pulley main body made of synthetic resin covers the serration portion 33a formed on the outer circumference of the pulley boss 33. 34 is integrally molded. Both ends of the pulley boss 33 are rotatably supported by the front housing 23 and the front cover 25 by two ball bearings 35 and 36, respectively, and the pulley shaft 32 is supported by the ball bearing 37 in the center housing 22.
Is rotatably supported by. The pulley boss 33 and the drive pulley body 34 form the drive pulley 59 of the present invention.

The front end inner circumference of the steering shaft 29 is relatively rotatably fitted to the rear end outer circumference of the pulley shaft 32, and the torsion bar 38 is inserted into the hollow part of the steering shaft 29 and the hollow part of the pulley shaft 32. Both ends are fitted and connected by pins 39 and 40, respectively. Therefore, the steering torque input to the steering shaft 29 is transmitted from the steering shaft 29 to the torsion bar 38.
Will be transmitted to the pulley shaft 32 via
A steering torque sensor 41 provided inside the center housing 22 detects the steering torque based on the amount of twist of the torsion bar 38.

As is apparent from FIGS. 2 and 4, the steering torque sensor 41 includes a cylindrical slider 42 supported on the outer periphery of the pulley shaft 32 so as to be relatively non-rotatable and slidable in the axial direction, and a steering shaft 29. A guide pin 43 that is fixed and fits into the inclined groove 42a formed in the slider 42, a magnetic ring 44 that is fixed to the outer circumference of the synthetic resin slider 42, and a magnetic ring that is fixed to the inner circumference of the center housing 22. There is provided a differential transformer 45 facing the motor 44, and a coil spring 46 for biasing the slider 42 forward so as to prevent looseness between the guide pin 43 and the inclined groove 42a.

As shown in FIG. 5, the steering torque sensor 41
The differential transformer 45 includes a primary coil 48 connected to an AC power supply 47, a first secondary coil 49, and a second secondary coil 50, and the magnetic ring 44 has first and second secondary coils. A movable iron core arranged between the next coils 49 and 50 is configured.

As is apparent from FIG. 2, the front end portion of the pulley shaft 32 and the pulley boss 33 are joined at the serration joint portion 51, and the pulley shaft 32 is
Are coupled via a tapered coupling portion 52 that tapers toward the front end of the. A nut 53 is screwed into the front end of the pulley shaft 32, and the load from the nut 53 urges the pulley boss 33 rearward along the pulley shaft 32 so that the taper coupling portion 52 is brought into close contact with a sufficient surface pressure. The pulley shaft 32 and the pulley boss 33 can be firmly integrated. As a result, it is possible to eliminate the influence of minute backlash existing in the serration coupling portion 51, suppress the generation of noise, and improve the steering feeling. When the nut 53 is tightened, the drive pulley 59 can move in the axial direction, so that an unreasonable load is prevented from being applied to the drive pulley casing 12.

As is apparent from FIGS. 2 and 3, the two operation cables 15 and 16 are composed of a synthetic resin outer tube 15o formed by molding a coil spring having a substantially rectangular cross section.
16o and inner cables 15i and 16i made of a twisted metal wire slidably housed therein. Short columnar pins 54, 54 fixed to the ends of the two inner cables 15i, 16i are fitted into pin holes 34a, 34a formed on both end faces of the drive pulley body 34, and extend from the pins 54, 54. The inner cables 15i and 16i are wound in a direction in which they approach each other along a single spiral groove 34b formed on the outer periphery of the drive pulley main body 34, and then pulled out in a direction orthogonal to the axis of the pulley shaft 32.

The bottoms of the pin holes 34a, 34a of the drive pulley body 34 made of synthetic resin reach the boundary between the serration portion 33a of the pulley boss 33 and the drive pulley body 34. When the pins 54, 54 are removed, The boundary portion can be easily visually checked. Therefore, it is possible to reliably detect a processing error such as the drive pulley main body 34 being molded in an improper state in which the serrated portion 33a is not formed on the pulley boss 33.

Two cylindrical connecting portions 23b, 23b are formed in the front housing 23, and the boss portions 56a, 56a of the outer tube connecting members 56, 56 are fixed inside them. Pipe part 56 extending from the boss parts 56a, 56a to the outside of the connection parts 23b, 23b
b and 56b are fitted to the outer peripheries of the outer tubes 15o and 16o, and the caulked portions 56c and 56c are caulked, whereby the ends of the outer tubes 15o and 16o are fixed to the front housing 23. Outer tube coupling member 56,
Guide bushes 57, 57 made of synthetic resin having good sliding properties are held on the inner circumferences of the boss portions 56a, 56a of 56 in order to prevent the inner cables 15i, 16i and the boss portions 56a, 56a from being directly rubbed. .

The connecting portion 23b of the front housing 23,
23b to the predetermined position of the outer tubes 15o and 16o of the operation cables 15 and 16 (for example, the pipe portions 56b and 56 of the outer tube coupling members 56 and 56).
(From b to the exposed portion) are covered with rubber covers 58, 58. The rubber covers 58, 58 having elasticity include the outer circumferences of the connecting portions 23b, 23b of the front housing 23,
Since the outer tubes 15o and 16o are closely adhered to the outer peripheries of the outer tubes 15 and sealing, the outer tubes 15o and 16o are joined to the front housing 23 by caulking portions 56c and 56c of the outer tube connecting members 56 and 56 and the outer tube connecting members 56 and 56. It is possible to prevent water from entering through the gaps between the boss portions 56a, 56a and the connecting portions 23b, 23b.

Since the two ball bearings 35 and 36 supporting the pulley boss 33 are of a waterproof type inside the front housing 23 and the front cover 25 which house the drive pulley 59, there is no risk of the drive pulley 59 getting wet. Since the drive pulley 59 to the predetermined positions of the outer tubes 15o and 16o are housed in the hermetically sealed space as described above, the drive pulley casing 12 is arranged in the vehicle compartment and the drinking water which the occupant has spilled is splashed. Even when the outer tubes 15o and 16o and the inner cables 15i and 16i slide, water adheres to the outer tubes 15o and 16o and freezes when the temperature is low, which hinders the smooth movement of the operation cables 15 and 16.
It is possible to prevent the durability of the operation cables 15 and 16 from being deteriorated by i and 16i rusting.

As shown in FIGS. 7 and 8 , the driven pulley casing 14 is composed of an upper housing 61 and a lower housing 62 which are connected by bolts (not shown).
The gear casing 19 is composed of a gear casing main body 63 and an upper cover 64 joined to the upper surface of the gear casing main body 63 by bolts (not shown). The lower housing 62 and the upper cover 64 are joined by a plurality of bolts 65. To be done.

A ball bearing 66 provided on the upper housing 61, a ball bearing 67 provided on the lower housing 62, two ball bearings 68 and 69 provided on the gear casing main body 63, and a pulley shaft 70.
Is rotatably supported. The upper two ball bearings 66, 67 do not directly support the pulley shaft 70, but support the pulley boss 71 fixed to the outer periphery of the pulley shaft 70. The ball bearing 66 provided in the upper housing 61 is retained by an annular nut 72, and the lower ball bearing 69 provided in the gear casing main body 63 is retained by a bag-shaped nut 73.

The upper end portion of the pulley shaft 70 and the pulley boss 71 are joined together at a serration joint portion 74, and also via a tapered joint portion 75 which is tapered toward the upper end portion of the pulley shaft 70. A nut 76 is screwed onto the upper end of the pulley shaft 70,
By urging the pulley boss 71 downward along the pulley shaft 70 by the load from the nut 76, the taper coupling portion 75 is brought into close contact with the pulley shaft 70 with sufficient surface pressure, and
By firmly integrating the pulley boss 71 with each other, it is possible to eliminate the influence of minute play existing in the serration joint portion 74, suppress the generation of noise, and improve the steering feeling. When the nut 76 is tightened, the driven pulley 60 can move in the axial direction, so that an unreasonable load is prevented from being applied to the driven pulley casing 14 and the gear casing 19.

The serration portion 7 on the outer periphery of the pulley boss 71
A driven pulley main body 77 made of a synthetic resin is integrally molded in 1a, and short cylindrical pins 78, 78 fixed to the ends of the inner cables 15i, 16i of the two operation cables 15, 16 are driven pulley main bodies. Two inner cables 15i, 16i fitted in pin holes 77a, 77a formed on both end surfaces of 77 and extending from the pins 78, 78 are formed along one spiral groove 77b formed on the outer periphery of the driven pulley body 77. After being wound in a direction in which they approach each other, they are pulled out in a direction orthogonal to the axis of the pulley shaft 70. The pulley boss 71 and the driven pulley body 77 constitute the driven pulley 60 of the present invention.

The bottoms of the pin holes 77a, 77a of the driven pulley main body 77 made of synthetic resin reach the boundary between the serrated portion 71a of the pulley boss 71 and the driven pulley main body 77, and when the pins 78, 78 are removed, The boundary portion can be easily visually checked. Therefore, it is possible to reliably find a processing error such as the driven pulley body 77 being molded in a state where the serrated portion 71a is not formed on the pulley boss 71.

The driven pulley casing 14 is formed with two cylindrical connecting portions 14a, 14a, and the boss portions 79a, 79a of the outer tube connecting members 79, 79 are fixed inside them. Bosses 79a, 79a
Pipe portion 79 extending from the outside to the connection portions 14a, 14a
b and 79b are fitted to the outer peripheries of the outer tubes 15o and 16o, and the caulked portions 79c and 79c are caulked, whereby the ends of the outer tubes 15o and 16o are fixed to the driven pulley casing 14. Outer tube connecting member 7
On the inner circumferences of the boss portions 79a, 79a of 9, 79, there are held guide bushes 80, 80 made of synthetic resin having good sliding property so as to prevent the inner cables 15i, 16i and the boss portions 79a, 79a from directly rubbing. To be done.

From almost the entire driven pulley casing 14 through the connecting portions 14a, 14a, the operation cables 15, 1 are connected.
A single rubber cover 81 covers up to predetermined positions of the outer tubes 15o and 16o of 6 (for example, from the pipe portions 79b and 79b of the outer tube coupling members 79 and 79 to exposed portions). The rubber cover 81 can not only reliably seal the caulked portions 79c, 79c of the outer tube coupling members 79, 79 where water is most likely to enter, but also the split surfaces of the upper housing 61 and the lower housing 62 of the driven pulley casing 14 and the like. ,
It is possible to prevent the intrusion of water from the ball bearing 66 that supports the upper end of the pulley shaft 70.

As a result, the waterproofness of the driven pulley casing 14, which is arranged in the lower part of the engine room and is easier to get wet with water than the drive pulley casing 12, can be improved, and the outer tubes 15o and 16o and the inner cables 15i and 16i can be enhanced. Moisture attached to the slide parts of the inner cables 15i, 16 may be blocked by freezing of the operation cables 15, 16 at low temperatures, and the inner cables 15i, 16
It is possible to prevent i from rusting and lowering the durability of the operation cables 15 and 16.

As is apparent from FIG. 8, the tension adjusting mechanism 92 housed inside the driven pulley casing 14 has a torsion spring 94 whose central portion is supported by a pin 93, and both ends of the torsion spring 94. And two rollers 95, 95 supported by the torsion spring 9 and the two rollers 95, 95.
The elastic force of 4 pushes against the two inner cables 15i and 16i of the operation cables 15 and 16, respectively.

At the upper part of the gear casing 19, which is sealed between the driven pulley casing 14 and the driven pulley casing 14, a worm wheel 82 fixed to the pulley shaft 70 and an actuator 2 composed of an electric motor.
Worm 83 fixed to the output shaft 20a of 0 (see FIG. 1)
And are in mesh. The steering gear box 13 is attached to the pinion 84 formed on the lower portion of the pulley shaft 70.
The rack 85 (see FIG. 1) is meshed, and the rack 85 is urged toward the pinion 84 at the meshing portion.

That is, the slide member 86 is slidably fitted in the through hole 63a formed in the gear casing main body 63 through the O-ring 87, and the spring seat 88 and the slide member 86 screwed to the through hole 63a. The low-friction member 90 provided on the slide member 86 comes into contact with the back surface of the rack 85 by the elastic force of the coil spring 89 arranged between them. As a result, when the rotation of the pulley shaft 70 is transmitted to the rack 85 via the pinion 84 and the wheels WL and WR are steered, the rack 85 is prevented from rattling or bending without receiving a large sliding resistance. It can be operated smoothly.

As shown in FIGS. 2, 7, and 9, the diameter D1 of the drive pulley 59 is larger than the diameter D2 of the driven pulley 60.
Is set small.

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

The steering torque detected by the steering torque sensor 41 is input to the control device 18, and the control device 18 controls the operation of the actuator 20 based on the steering torque. That is, when the steering handle 11 is operated to turn the vehicle, the steering torque is transmitted to the pulley shaft 32 via the steering shaft 29 and the torsion bar 38 and is wound around the drive pulley main body 34, as shown in FIG. The inner cables 15i, 16i of the cables 15, 16 are pulled and the other inner cables 15i, 16i are loosened, whereby the rotation of the drive pulley 59 is transmitted to the driven pulley 60. As a result, the pulley shaft 70 shown in FIG. 7 rotates, and the wheels WL, WR pass through the pinion 84, the rack 85, and the tie rods 17L, 17R in the steering gear box 13.
The steering torque is transmitted to.

When the steering torque is not input to the steering wheel 11, the torsion bar 38 is not twisted and deformed, the steering shaft 29 and the pulley shaft 32 are held in the same phase, and as shown in FIG. The guide pin 43 of the shaft 29 is the inclined groove 42.
At the center of a, the slider 42 is held at the vertical center position. At this time, as shown in FIG.
The magnetic ring 44 provided on the secondary coil 4 is located at an intermediate position between the first secondary coil 49 and the second secondary coil 50.
It is detected that the output voltages of 9, 50 are equal and the steering torque is zero.

When the steering handle 11 is operated to the right and steering torque in the direction of arrow a in FIG. 6A is input to the steering shaft 29, the torsion bar 38 is twisted and deformed, and the steering shaft 29 and the pulley shaft are deformed. 32 (i.e., the slider 42 that cannot rotate relative to the pulley shaft 32) causes a relative angle difference, so that the guide pin 43 of the steering shaft 29 is provided.
The slider 42 pushed by the inclined groove 42a slides upward. As a result, the output voltage of the upper first secondary coil 49 increases and the output voltage of the lower second secondary coil 50 decreases, and the steering torque in the right turning direction is detected based on the voltage difference. It Similarly, the steering wheel 1
When the steering torque is input to the steering shaft 29 in the direction of arrow b in FIG. 6C, the torsion bar 38 is twisted and deformed, and the steering shaft 29 and the pulley shaft 32 (that is, the slider 42). , A reverse relative angle difference is generated, so that the slider 42 pushed by the guide groove 43 of the steering shaft 29 in the inclined groove 42a slides downward. As a result, the output voltage of the upper first secondary coil 49 decreases and the output voltage of the lower second secondary coil 50 increases, and the steering torque in the left turning direction is detected based on the voltage difference. It

As described above, when the steering torque sensor 41 detects the steering torque, the control device 18 drives the actuator 20 so that the steering torque detected by the steering torque sensor 41 is maintained at a preset predetermined value. To do. As a result, the torque of the actuator 20 is transmitted to the pulley shaft 70 via the worm 83 and the worm wheel 82.
And the steering wheel operation by the driver is assisted. Steering torque sensor 4 having differential transformer 45
By combining 1 and the actuator 20,
The actuator 20 can be operated only by electric control, and the structure of the control system is simplified. As shown in FIG. 9, the steering friction torque Tsf applied to the steering handle 11 is the first component resulting from the frictional force Fc of the operation cables 15 and 16 and the meshing portion of the rack 85 of the steering gear box 13 and the pinion 84. The second component resulting from the frictional force Fp is added, and is represented by the following equation.

Tsf = R1.Fc + R3. (R1 / R
2) · Fp where R1 is the radius of the drive pulley 59 (R1 = D1 / 2),
R2 is the radius of the driven pulley 60 (R2 = D2 / 2), D3
And R3 are the diameter and radius of the pinion 84 (R3 = D3 / 2), respectively.

The first component R1 · Fc resulting from the frictional force Fc of the operation cables 15 and 16 is the driven pulley 60.
Even if the radius R2 of the drive pulley 59 is the same as the conventional one, it can be reduced by making the radius R1 of the drive pulley 59 smaller than the conventional one.

R3 · (R1 / R1) which is the second component resulting from the frictional force Fp of the meshing portion of the rack 85 and the pinion 84.
R2) · Fp can be reduced by making the ratio R1 / R2 of the radius R1 of the drive pulley 59 to the radius R2 of the driven pulley 60 smaller than the conventional one, even if the radius R3 of the pinion 84 is the same as the conventional one.

In this way, the diameter D1 of the drive pulley 59 is made smaller than the diameter D2 of the driven pulley 60, and the steering friction torque Tsf of the steering handle 11 is made smaller, so that the steering handle 11 returns to the neutral position better. In addition, the load at the beginning of turning the steering wheel 11 can be reduced to improve the steering feeling.

The tension adjusting mechanism 92 housed inside the driven pulley casing 14 allows the operation cable 15,
A predetermined tension is applied to the two inner cables 15i, 16i of 16 to prevent the inner cables 15i, 16i from loosening. By providing the tension adjusting mechanism 92 on the driven pulley 60 side instead of the driving pulley 59 side, the following effects can be obtained. That is, in the portion wound around the small-diameter drive pulley 59, the inner cables 15i, 1
Since the 6i is strongly bent, the rigidity of the inner cables 15i and 16i becomes high in the vicinity of the drive pulley 59. Therefore, if the tension adjusting mechanism 92 is provided near the drive pulley 59, the pressing force of the rollers 95, 95 required to generate a predetermined tension on the inner cables 15i, 16i increases, and as a result, the inner cable 15i, 16i increases. 15
There is a problem that the frictional resistance of i and 16i increases.

On the other hand, since the inner cables 15i and 16i are not bent so strongly at the portion wound around the large diameter driven pulley 60, the rigidity of the inner cables 15i and 16i does not become so high near the driven pulley 60. Therefore, if the tension adjusting mechanism 92 is provided near the driven pulley 60 as in the present embodiment, the inner cables 15i and 16i are provided.
Rollers 95, 95 necessary to generate a predetermined tension on the
As a result, it is possible to minimize the increase in the frictional resistance of the inner cables 15i, 16i due to the pressing force and improve the steering feeling.

Although the embodiments of the present invention have been described in detail above, the present invention can be modified in various ways without departing from the scope of the invention.

For example, in the embodiment, the actuator 20 assists the driver's steering operation.
The present invention can also be applied to a cable-type steering device for manual steering that does not include the actuator 20.

[0049]

As described above, according to the invention described in claim 1, since the diameter of the driving pulley is made smaller than the diameter of the driven pulley, steering by the frictional force of the operation cable or the frictional force of the steering gear box is performed. It is possible to reduce the friction torque, improve the return of the steering wheel to the neutral position, and reduce the load at the beginning of turning the steering wheel to improve the steering feeling.

According to the invention described in claim 2,
Since the tension adjustment mechanism that adjusts the tension of the operation cable is provided adjacent to the driven pulley, the tension required to give a predetermined tension to the operation cable compared to when the tension adjustment mechanism is provided adjacent to the drive pulley. The pressing force of the adjusting mechanism is reduced, and the increase in the frictional force of the operation cable due to the pressing force can be suppressed to the minimum to improve the steering feeling.

[Brief description of 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.

3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a perspective view of a steering torque sensor.

FIG. 5 is a circuit diagram of a differential transformer of a steering torque sensor.

FIG. 6 is an operation explanatory view of a steering torque sensor.

7 is an enlarged sectional view taken along line 7-7 of FIG.

8 is a sectional view taken along line 8-8 of FIG.

FIG. 9 is an explanatory diagram of operation

[Explanation of symbols]

11 steering wheel 13 Steering gear box 15 Operation cable 16 Operation cable 59 Drive pulley 60 driven pulley 92 Tension adjustment mechanism WL wheel WR wheels

Claims (2)

[Claims] 1. A drive pulley (59) and wheels (WL, WR) which are connected to a steering handle (11) and rotate.
The driven cable (60) that is connected to the steering gear box (13) for steering the
5, 16), and the steering torque input to the steering wheel (11) is transmitted to the steering gear box (13) via the operation cables (15, 16) in the cable type steering device, which includes a drive pulley (59). The cable type steering device is characterized in that the diameter of the driven pulley is smaller than the diameter of the driven pulley (60). 2. The cable type steering system according to claim 1, further comprising a tension adjusting mechanism (92) provided adjacent to the driven pulley (60) for adjusting the tension of the operation cables (15, 16). apparatus.