JP3547508B2 - Locking device for steering shaft - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a steering shaft lock device used for preventing theft of a vehicle or the like.
[0002]
[Prior art]
As a lock device for a steering shaft, a device provided with a key engaged by a lock operation in a key groove of a key ring provided on the steering shaft has been conventionally used, and the rotation of the steering shaft is regulated to prevent theft. (See Japanese Patent Application Laid-Open No. 57-191149).
[0003]
[Problems to be solved by the invention]
In the conventional locking device, when an excessive rotational force is applied to the steering wheel, the key or the key groove is broken, and the steering wheel can be operated. Therefore, the theft could not be sufficiently prevented.
[0004]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a steering shaft locking device that can solve the above problems.
[0005]
[Means for Solving the Problems]
The present invention relates to a steering shaft locking device including an engagement portion provided on a steering shaft and a lock member engaged with the engagement portion by a locking operation, wherein the engagement portion and the lock member include the steering shaft. Are engaged via a surface inclined with respect to the axial direction of the steering shaft so that the shaft moves in the axial direction by the action of a torque greater than or equal to a set value. And an auxiliary lock member engaged by the axial movement of the steering shaft.
[0006]
It is preferable that means is provided for preventing the steering shaft from moving in the axial direction when the auxiliary engagement portion and the auxiliary lock member are engaged.
[0007]
It is preferable that the steering shaft includes a first shaft and a second shaft which are relatively moved in the axial direction by the action of an impact corresponding to the torque equal to or greater than the set value.
[0008]
Function and Effect of the Invention
According to the configuration of the present invention, when the lock member is engaged with the engagement portion of the steering shaft, the rotation operation of the steering wheel is prevented. If the rotational force acting on the steering wheel is not excessive, that is, if the torque acting on the steering shaft is smaller than a set value, the steering shaft will not move in the axial direction.
[0009]
When the rotational force acting on the steering wheel becomes excessive, that is, when the torque acting on the steering shaft exceeds a set value, the engaging portion and the lock member engage via the surface inclined with respect to the axial direction of the steering shaft. Therefore, an excessive axial force acts on the steering shaft. As a result, the steering shaft moves in the axial direction. By the axial movement of the steering shaft, the auxiliary lock member is engaged with the auxiliary engagement portion of the steering shaft, and the rotation operation of the steering wheel can be prevented again. At this time, even if the engagement portion or the lock member is broken, the rotation of the steering wheel can be prevented by the engagement between the auxiliary engagement portion and the auxiliary lock member. Thereby, the anti-theft effect can be improved.
[0010]
When the steering shaft moves in the axial direction after the engagement between the auxiliary engagement portion and the auxiliary lock member, the engagement is released, the steering angle is limited, but the steering wheel can be operated to rotate. Alternatively, when the lock member is broken, the steering wheel can be rotated without limiting the steering angle. Therefore, the engagement between the auxiliary engagement portion and the auxiliary lock member is prevented by preventing the axial movement of the steering shaft when the auxiliary engagement portion and the auxiliary lock member are engaged. preferable.
[0011]
By forming the steering shaft from a first shaft and a second shaft which move relative to each other in the axial direction by the action of an impact corresponding to the torque equal to or greater than the set value, it is possible to absorb the impact acting on the driver in the event of a collision. it can.
[0012]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0013]
The shock absorbing type steering device 1 shown in FIG. 1 includes a cylindrical column 2 and a steering shaft 4 supported on the column 2 via a bearing 3, and is attached to the vehicle body via the column 2. A steering wheel 5 is connected to one end of the steering shaft 4, and the rotation of the steering wheel 5 is transmitted to a tire (not shown) via the steering shaft 4 to steer the vehicle.
[0014]
The steering shaft 4 includes a first shaft 4a and a cylindrical second shaft 4b inserted into the first shaft 4a. A pair of circumferential grooves 6 are formed on the outer periphery of the first shaft 4a, and a through hole 7 communicating with the circumferential groove 6 is formed in the second shaft 4b, and the circumferential groove 6 and the through hole 7 are filled with a resin 8. Is done. When a certain or more axial force acts on the first shaft 4a, the resin 8 is broken, and the first shaft 4a and the second shaft 4b move relative to each other in the axial direction. Since the outer peripheral shape of the first shaft 4a and the inner peripheral shape of the second shaft 4b are non-circular, the first shaft 4a and the second shaft 4b are connected to be able to transmit rotation.
[0015]
As shown in FIG. 2, a key ring 11 is integrated with the outer periphery of the first shaft 4 a, and a key groove (engaging portion) 11 a is formed on the key ring 11 along a direction inclined with respect to the axial direction of the steering shaft 4. It is formed. A cylinder 12 is attached to the column 2, and the cylinder 12 holds a key (lock member) 13. The key 13 advances from the cylinder 12 by the lock operation, enters the column 2 from the opening 2a, and is inserted into the center of the key groove 11a. It is preferable that the locking operation is performed in a substantially straight-ahead steering state, and that the locking operation of the vehicle also serves as a stopping operation of the ignition switch, and the unlocking operation also serves as a starting operation of the ignition switch.
[0016]
As shown in FIGS. 1 and 3, at upper and lower positions of the key ring 11, ring members (auxiliary engagement portions) 15, 16 are integrated with the outer periphery of the first shaft 4a. A pair of flat surfaces 15a, 15b, 16a, 16b parallel to the axial direction are formed on the outer circumference of each ring member 15, 16 in parallel with each other. At a position above the ring member 15 above, a pair of pins (auxiliary lock members) 21a and 21b are fixed to the column 2, and at a position below the ring member 16 below the pair of pins (auxiliary lock member) ) 22a and 22b are fixed. Each of the pins 21a, 21b, 22a, and 22b protrudes from the inner peripheral surface of the column 2, and the protrusion dimension is larger than the distance from the inner peripheral surface of the column 2 to the outer cylindrical surface of each of the ring members 15, 16. Is slightly smaller than the distance from the inner peripheral surface to the flat surfaces 15a, 15b, 16a, 16b of the ring members 15, 16.
[0017]
At the upper position of the ring member 15 above and the lower position of the ring member 16 below, the first shaft 4a is formed with the circumferential grooves 4a ', 4a ". Above the upper circumferential groove 4a'. In the position, a pair of movable pins 26a and 26b are attached to the column 2, and a pair of movable pins 27a and 27b are attached to the column 2 at a position below the peripheral groove 4a ″ below the column. Each movable pin 26a, 26b, 27a, 27b is held by a holding member 26a ', 26b', 27a ', 27b' fixed to the column 2 so as to be movable in the radial direction of the first shaft 4a, and a spring 26a ", The first shaft 4a is pressed against the outer periphery of the first shaft 4a by the elastic force of 26b ", 27a", and 27b ".
[0018]
According to the above configuration, the key 13 is engaged with the key ring 11 provided on the first shaft 4a by abutting the side surfaces 11a ', 11a "of the key groove 11a. If the torque acting on the steering wheel 5 is not excessive and the torque acting on the first shaft 4a is smaller than a set value, the first shaft 4a does not move in the axial direction.
[0019]
When the rotational force acting on the steering wheel 5 becomes excessive and the torque acting on the first shaft 4a exceeds a set value, the side surfaces 11a 'and 11a "of the keyway 11a move with respect to the axial direction of the steering shaft 4. Due to the inclination, an excessive axial force acts on the steering shaft 4. As a result, the resin 8 connecting the first shaft 4a and the second shaft 4b is broken, and the first shaft 4a moves in the axial direction. In this embodiment, the direction of movement of the first shaft 4a is upward when the rotation direction of the steering wheel 5 is clockwise and downward when the rotation direction is counterclockwise. As shown in FIGS. 4 and 5, the pins 21a and 21b on the upper side come into contact with the flat surfaces 15a and 15b due to the axial movement and rotation of , Engages with the upper ring member 15. By this engagement, the rotation operation of the steering wheel 5 can be prevented again.In this case, even if the key ring 11 or the key 13 is broken, the pins 21a, 21b and the ring member 15 are engaged. Can prevent rotation of the steering wheel 5. When the first shaft 4a is moved downward in the axial direction and rotated, the flat surface 16a between the lower pins 22a and 22b and the ring member 16 is similarly formed. , 16b prevents rotation of the steering wheel 5. The rotation preventing force of the steering shaft 4 due to the engagement between the pins 21a, 21b, 22a, 22b and the ring members 15, 16 is reduced. 4 prevents rotation of the steering shaft 4 even if a torque greater than the set value acts on the steering shaft 4 Preferably set to be.
[0020]
When the first shaft 4a moves in the axial direction to disengage the pins 21a, 21b, 22a, 22b from the ring members 15, 16, the steering angle is limited by the engagement between the key ring 11 and the key 13. However, when the steering wheel 5 becomes rotatable and the key ring 11 or the key 13 is damaged, the steering wheel 5 becomes rotatable without limiting the steering angle. Therefore, when the pins 21a, 21b, 22a, 22b and the ring members 15, 16 are engaged, the distal ends of the movable pins 26a, 26b, 27a, 27b have the elastic force of the springs 26a ", 26b", 27a ", 27b". By inserting into the peripheral grooves 4a 'and 4a ", the first shaft 4a is engaged with the side surfaces of the peripheral grooves 4a' and 4a", thereby preventing the first shaft 4a from moving in the axial direction. The rotation of the steering shaft 4 is prevented by maintaining the engagement between the pins 21a, 21b, 22a, 22b and the ring members 15, 16.
[0021]
Further, in the above configuration, the steering shaft 4 is composed of the first shaft 4a and the second shaft 4b, and the impact energy can be absorbed by breaking the resin 8 by the action of the impact corresponding to the torque equal to or greater than the set value. It can also absorb the impact acting on the driver in the event of a collision.
[0022]
The present invention is not limited to the above embodiment. For example, when a torque equal to or more than the set value acts on the steering shaft, in the above embodiment, the tip of the movable pin is inserted into the circumferential groove of the steering shaft, but by inserting the movable pin into a through hole formed in the steering shaft, The steering shaft may be prevented from rotating as well as axially moving. In this case, since the movable pin and the through hole also function as an auxiliary lock member and an auxiliary engagement portion, the pins 21a, 21b, 22a, 22b and the ring members 15, 16 as in the above-described embodiment can be eliminated. . In the above embodiment, the key ring 11 having the key groove 11a is used as the engaging portion, and the key 13 inserted into the key groove 11a is used as the lock member. However, for example, the key 13 is formed spirally on the outer periphery of the steering shaft. The protrusion may be used as the engagement portion, and a key having a concave portion that can be fitted to the protrusion may be used as the lock member.
[Brief description of the drawings]
1 is a sectional view of a steering device according to an embodiment of the present invention; FIG. 2 is a sectional view taken along line II-II of FIG. 1; FIG. 3 is a sectional view taken along line III-III of FIG. 1; FIG. 5 is a sectional view for explanation. FIG. 5 is a sectional view taken along line VV in FIG.
4 Steering shaft 4a ', 4a "circumferential groove 11 key ring (engagement part)
11a ', 11a "Surface 13 inclined with respect to axial direction 13 Key (locking member)
15, 16 ring member (auxiliary engagement part)
21a, 21b, 22a, 22b Pin (auxiliary lock member)
26a, 26b, 27a, 27b Movable pin

Claims (3)

In a steering shaft locking device including an engagement portion provided on a steering shaft and a lock member engaged with the engagement portion by a lock operation, the engagement portion and the lock member are such that the steering shaft has a set value or more. The steering shaft is engaged via an inclined surface with respect to the axial direction of the steering shaft so as to move in the axial direction by the action of the torque, and an auxiliary engaging portion provided on the steering shaft and a steering shaft A steering shaft locking device, comprising: an auxiliary locking member that is engaged by axial movement. 2. The steering shaft locking device according to claim 1, further comprising means for preventing axial movement of the steering shaft when the auxiliary engagement portion and the auxiliary lock member are engaged. The steering shaft lock according to claim 1 or 2, wherein the steering shaft includes a first shaft and a second shaft that relatively move in the axial direction by the action of an impact corresponding to the torque equal to or greater than the set value. apparatus.

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