JPH0249102Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electric tilt steering device, in particular, to prevent rattling of the steering column during driving.

In recent years, it has become common to provide a driver's seat and a steering wheel with many degrees of freedom so that an optimal driving posture can be achieved depending on the physique of the driver. For example, there are tilt steering devices that allow you to change the height of the steering wheel, and the inclination of the steering column can be changed arbitrarily by operating a lock lever that protrudes from the steering bracket directly below the instrument panel. There is.

By the way, depending on the type of vehicle and the physique of the driver, the steering wheel may be located at the optimal position for the driver, but this may obstruct the driver from getting on or off the vehicle. It is very inconvenient as you have to jump up and down. In order to solve this problem, electric tilt steering devices have been considered, but since they use gears, it is impossible to avoid bumping, and even when driving, the steering column moves up and down by the amount of bumping. There was a fear that it would get rattled.

Based on this knowledge, it is an object of the present invention to provide an electric tilt steering device in which the steering column does not wobble even after adjusting the height of the steering handle.

The structure of the electric tilt steering device of the present invention that achieves this purpose includes a steering column rotatably supported via a tilt shaft to a tilt bracket fixed to the vehicle body, and a universal joint interposed in the middle. a steering shaft rotatably supported by the steering column such that the connection center of the universal joint coincides with the axis of the tilt shaft; and a steering shaft provided coaxially with the tilt shaft and integrally with the steering column. a worm wheel; a worm, one end of which is swingably held via a spherical joint in a gearbox integral with the tilt bracket and capable of moving toward and away from the worm wheel; and a worm that engages with the worm wheel; A motor is attached and connected to one end of the worm to drive and rotate the worm, and a motor is interposed between the gearbox and the worm and presses the worm against the worm wheel to prevent rattling of the steering column. a spring material for preventing rattling, and a worm rocking drive means that resists the spring force of the spring material and pulls the worm away from the worm wheel to return them to a normal rotatable meshing state. It is equipped with

Therefore, according to the present invention, the worm is engaged with the worm wheel that is integrated with the steering column so that it can move toward and away from the worm wheel, and when changing the tilt angle of the steering column, the worm is oscillated so that the worm is in the normal engaged state. The worm is displaced by a driving means, and the worm is driven and rotated by a motor, and when the tilt angle of the steering column is fixed, the worm is pressed against the worm wheel by the spring force of the spring material to eliminate bumps between them. Therefore, there is no play in the steering column, and an electric tilt steering device with excellent operability can be obtained.

Hereinafter, an embodiment of the electric tilt steering device according to the present invention will be described in detail with reference to FIGS. 1 to 5.

As shown in FIG. 1a showing the appearance of this embodiment and FIG. 1b showing its planar shape, the tilt bracket 11 fixed to the vehicle body side (not shown) has a tilt bracket 11 that is integrally attached to the lower end of the column top 12. A bifurcated fork 13 is rotatably supported via a pair of coaxial tilt shafts 14. The upper end of the steering shaft lower 16 is rotatably supported within the column lower 15, the upper end of which is located directly below the tilt bracket 11, and the lower end of the steering shaft upper 17 is rotatably supported within the column upper 12. They are connected via a universal joint 18, and the positional relationship between the tilt shaft 14 and the universal joint 18 is set such that the connection center of the universal joint 18 overlaps the axis of the tilt shaft 14.

Therefore, the column top 1 is centered around the tilt axis 14.
Even if you turn 2, the steering shaft lifts 1
7, operate the steering wheel (not shown) attached to the upper end of the steering shaft
7 can be smoothly transmitted to the steering shaft lower 16.

As shown in FIG. 2, which shows the cross-sectional structure of the main part of this embodiment, a gear box 19 that is integrally fixed to the tilt bracket 11 includes a gear box 19 that is integrally connected to the fork 13 so as to be coaxial with the tilt shaft 14. A fan-shaped worm wheel 20 fixedly attached to the gear box 19 is housed, and one end of a hollow worm 21 that meshes with the worm wheel 20 is provided in the gear box 19 via a spherical joint 22.

Therefore, the worm 21 is rotated with respect to the gearbox 19 by the spherical joint 22, and while driving the worm wheel 20, it is possible to change the depth of engagement with the worm wheel 20.

Inside the worm 21 is a drive shaft 2.
3 is rotatably fitted to one end of the drive shaft 23, and a spindle 26 is fitted to one end of the drive shaft 23, which is connected to a motor 25 installed in the gearbox 19 via a reduction gear 24. A timing screw 27 that can rotate integrally with the drive shaft 23 is slidably fitted to the other end of the drive shaft 23 that rotates integrally with the spindle 26 . Female thread cylinder 2 integrally molded on the other end side
It is screwed into 8. A cylindrical link frame 29 which is prevented from rotating with respect to the gearbox 19 is supported on the female threaded cylinder 28 via a pair of bearings 30 so as to be able to reciprocate from side to side in FIG. It is connected to the timing screw 27 by a set bolt 31 so as to be relatively rotatable.

As shown in FIG. 3, which shows the external appearance of the timing screw 27, a portion of the thread 32 of the timing screw 27 has several turns completely cut out, and a timing key 33 that slides therein is inserted into the screw thread 32. It is attached to the threaded cylinder 28.

Therefore, when the motor 25 is operated and the timing screw 27 is rotated, the female threaded cylinder 2 is rotated until one end surface of the threads 32 facing each other with the timing key 33 in between comes into contact with the timing key 33.
8, only the timing key 33 rotates and is displaced in the left-right direction in FIG.
, drive shaft 23 and worm 2
1 rotates together.

As shown in FIG. 4, which shows the cross-sectional structure in the direction of - arrow in FIG. 2, and FIG. 5, which shows the cross-sectional structure in the direction of - arrow in FIG. The force adjustment nut 36 is screwed into the gearbox 19,
The link position adjustment screw 35 has a connecting plate 3.
7 and a disc spring 38 which is interposed between the connecting plate 37 and the spring force adjusting nut 36 and comes into contact with them are fitted. Link position adjustment screw 3
5 is in contact with the lower end of a frame-shaped link support plate 39 surrounding the female threaded tube 28, and a slide shaft 40 provided at the upper end of this link support plate 39 in parallel with the tilt shaft 14 is It is attached to the gearbox 19 so as to be slidable up and down in FIG. 4. The upper ends of a pair of bell-crank-shaped shot links 43 connected to the upper ends of a pair of toggle links 42 via coaxial pins 41 are pivotally attached to the slide shaft 40. The lower ends are connected to the connecting plate 37 via coaxial pins 44, respectively.
is connected to both ends of. Further, one end of a pair of long links 45 is connected to the toggle link 42 and the shot link 43 by the pin 41, and the other ends of the pair of long links 45 are connected to the link frame 29 through coaxial pins 46, respectively.
1, 44, and 46 are set parallel to the tilt axis 14.

Here, when the slide shaft 40 and the axes of the pins 41 and 44 are on the same plane, the timing key 33
The dimensional positional relationship between the two is set so that the timing screw 27 is located at the center of the non-threaded portion of the timing screw 27, and in order to detect this state, a dog 47 formed at one end of the shot link 43 is used. An abuttable limit switch 48 is mounted on the gearbox 19.

Therefore, when the limit switch 48 is pressed by the dog 47, the slide shaft 40 and the axes of the pins 41 and 44 are located on the same plane, and the spring force of the disc spring 38 is directly applied to the long link 45.
This functions to push the worm 21 toward the worm wheel 20 side via the timing screw 27, eliminating the bump between the worm wheel 20 and the worm 21, and preventing the worm wheel 20 from shaking against the worm 21. . In this case, by adjusting the amount by which the spring force adjustment nut 36 is screwed into the gear box 19, the pressing force of the worm 21 against the worm wheel 20 can be arbitrarily changed.

On the other hand, attach the timing screw 27 to the female threaded tube 2.
8 and move the long link 45 in the left-right direction in FIG. 5, the short link 43 and the toggle link 42 become inclined,
The connecting plate 37 is lifted up, but since the connecting plate 37 is barely floating up from the disc spring 38, the link support plate 39 and the like are lowered due to their own weight until they come into contact with the link position adjustment screw 35.
Along with this, the worm 21 released from the spring force of the disc spring 38 separates from the worm wheel 20,
Transition to normal meshing state. In this case, the worm 21 relative to the worm wheel 20 can be adjusted by adjusting the screwing amount of the link position adjustment screw 35.
It is possible to set a good meshing condition.

In other words, the timing screw 2 shown in FIG.
7 and the timing key 33, when the motor 25 is activated to drive the spindle 26, the rotational force of the spindle 26 is transferred to the drive shaft 2.
3 to the timing screw 27, and the end surface of the thread 32 is connected to the timing key 33.
The timing screw 27 rotates relative to the female threaded cylinder 28 until it comes into contact with the internal threaded cylinder 28, and the movement of the timing screw 27 is transmitted from the link frame 29 to the long link 45 via the pin 46, and the dog 47 is removed from the limit switch 48. At the same time, the worm 21 is released from the worm wheel 20, and in this state, the thread 32 of the timing screw 27 is engaged with the timing key 33, and the rotation of the timing screw 27 is transmitted to the worm 21, which is integrated with the female thread cylinder 28. , the column upper 12 can be rotated about the tilt shaft 14 via the worm wheel 20.

After setting the column top 12 to the desired inclination angle in this way, the motor 25 is reversed until the dog 47 contacts the limit switch 48 again. There is only relative rotation, and the worm wheel 20 is in a stationary state, so there is no possibility that the inclination of the column upper 12 will change. As a result, the worm 21 once again engages the disc spring 3.
It is pressed against the worm wheel 20 by the spring force of 8, and can prevent these rattling.

As described above, in this embodiment, the motor 25, timing screw 27, female thread cylinder 28, link frame 29, timing key 33, link position adjustment screw 35, connection plate 37, link support plate 39, slide shaft 40, pin 41 ,44,4
6. The toggle link 42, short link 43, long link 45, etc. constitute the worm swing driving means of the present invention, and one motor 25 drives the worm wheel 20 and moves the worm 21 towards and away from the worm wheel 20. However, it is also possible to move the worm 21 towards and away from the worm wheel 20 using a solenoid or the like via a boosting mechanism using a lever, or by using a cam driven by a motor to move the worm 21 towards and away from the worm wheel 20. It may also be moved. In these cases, there is no need for the worm 21 to have a dual shaft structure as in this embodiment, and a simple mechanism can be achieved. Furthermore, if the motor 25 is attached to the gearbox 19 so that the rotation axis of the motor 25 is perpendicular to the drive shaft 23, the space on the driver's seat side can be further expanded.

[Brief explanation of the drawing]

Fig. 1a is a front view showing the external appearance of the electric tilt steering device according to the present invention, Fig. 1b is a plan view thereof, Fig. 2 is a sectional view showing the internal structure of the main part, and Fig. 3 is a timing screw. 4 is a sectional view taken along the − arrow in FIG. 2,
FIG. 5 is a cross-sectional view of the bracket in the direction indicated by the - arrow. In the figure, 11 is a tilt bracket, 12 is a tilt bracket, and 12 is a tilt bracket.
13 is a fork, 14 is a tilt axis, 15 is a column lower, 16 is a steering shaft lower, 17 is a steering shaft top, 18 is a universal joint, 19 is a gear box, 20
is a worm wheel, 21 is a worm, 22 is a spherical joint, 25 is a motor, 27 is a timing screw, 28 is a female thread cylinder, 29 is a link frame,
33 is a timing key, 35 is a link position adjustment screw, 37 is a connection plate, 38 is a disc spring, 39 is a link support plate, 40 is a slide shaft, 41,
44 and 46 are pins, 42 is a toggle link, 43 is a short link, 45 is a long link, 47 is a dog, and 48 is a limit switch.

Claims (1)

[Scope of utility model registration request] A steering column is rotatably supported via a tilt shaft to a tilt bracket fixed to the vehicle body, and a universal joint is interposed in the middle, and the connection center of the universal joint is the axis of the tilt shaft. a steering shaft rotatably supported by the steering column so as to coincide with the steering column; a worm wheel coaxially with the tilt axis and integrally provided with the steering column; a worm which is swingably held via a joint and can move towards and away from the worm wheel and which engages with the worm wheel; and a worm which is attached to the gearbox and connected to one end of the worm to drive and rotate the worm. a motor, a spring material interposed between the gearbox and the worm and for pressing the worm against the worm wheel to prevent rattling of the steering column; and a spring of the spring material. and worm rocking drive means for separating the worm from the worm wheel against a force to return the worm to a normal rotatable meshing state.