JP4534965B2 - Steering system - Google Patents

Description

  The present invention relates to a steering system, and more particularly to an improvement in a steering lock mechanism that restricts rotation of a steering wheel during parking.

Conventionally, a steering lock mechanism has been widely used to prevent theft of a vehicle. The steering lock mechanism generally includes a lock piece, and the rotation of the steering wheel is restricted by engaging and disengaging the lock piece with the steering shaft. For example, when the ignition key is rotated to the off position, the lock piece is mechanically or electrically operated to engage with a groove formed in the steering shaft, thereby rotating the steering shaft, that is, making the steering wheel unrotatable. . There is also a proposal of a steer lock mechanism having a lock member that moves in a direction along the steering shaft. For example, in a steering lock mechanism disclosed in Patent Document 1, a lock member is disposed inside a column cover. The lock member moves in the axial direction of the steering shaft by a mechanism using a cam mechanism or an electromagnetic solenoid, and connects the steering boss of the steering wheel and the column cover to prevent the steering wheel from rotating.
Japanese Utility Model Publication No. 63-19454

  However, the conventional steering lock mechanism is disposed on the steering column in the column cover. And as a drive source which drives the lock member of a lock mechanism, an electromagnetic solenoid and a motor are used, for example, and a cam mechanism like patent document 1 is used. Incidentally, the steering column has a structure that absorbs shock in the event of a vehicle collision. For example, when the impact occurs, the steering column shrinks with a predetermined stroke to reduce the protrusion of the steering column to the driver side, or when the driver collides with the steering wheel, the steering column retracts The damage to the person is reduced. When a lock mechanism is arranged on such a steering column, in order to secure the required sliding stroke of the steering column and to obtain an impact absorbing effect, the steering column is arranged in the axial direction of the steering shaft by an amount corresponding to the arrangement space of the locking mechanism. Had to be extended to. In order to cope with the extension of the steering column, the vehicle size has been increased and the living space has been reduced.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a steering system having a steering lock mechanism capable of shortening the steering column while maintaining the function of the conventional steering column. .

  In order to solve the above-mentioned problems, in a steering system according to an aspect of the present invention, a steering wheel that is rotated to steer a vehicle, and a steering wheel that fixes the steering wheel to a tip and transmits the rotational force of the steering wheel. A shaft, an inner cylinder formed on the outer periphery of the steering shaft and rotating together are rotatably housed, and an outer cylinder fixed to a fixed portion of the vehicle, and a built-in steering wheel. And locking means including a lock piece that can be advanced and retracted to restrict the rotation of the steering wheel.

  According to this aspect, since the lock means including the lock piece that can be moved back and forth is built in the steering wheel, the space in which the lock means is disposed in the steering column becomes unnecessary. As a result, for example, the steering column can be shortened while maintaining the conventional shock absorbing function.

  In the above aspect, the outer cylinder extends to the inside of the steering wheel, and the locking means engages the lock piece and the outer cylinder inside the steering wheel. Good. In this case, since the engagement between the lock piece and the outer cylinder is performed inside the steering wheel, it becomes difficult to see the engagement portion from the outside, making it difficult to unlock the lock state and improving the safety of the lock state. .

  In the above aspect, the lock piece may be advanced and retracted in the diameter direction of the steering wheel. According to this aspect, the locked state can be achieved only by extending the outer cylinder in the axial direction of the steering shaft and forming the engaging portion with the lock piece on the side surface. As a result, it is possible to simplify the components and the lock structure.

  Moreover, the said aspect WHEREIN: The said outer cylinder may have an engaging groove engaged with the said lock piece. Here, the engagement groove may be any shape as long as it can engage with the lock piece and prevent rotation of the steering wheel. For example, the engagement groove may be a simple circular shape in addition to a square groove or an elliptical groove. According to this aspect, the engagement with the lock piece can be realized firmly only by cutting out the side surface of the outer cylinder to form the engagement groove. As a result, the lock structure can be reduced in size while suppressing an increase in the number of parts.

  According to the steering system of the present invention, the steering column can be shortened while maintaining the conventional function.

  Hereinafter, an embodiment of the present invention (hereinafter referred to as an embodiment) will be described with reference to the drawings.

  The steering system of the present embodiment incorporates locking means including a locking piece that can be moved forward and backward inside the steering wheel. The lock piece moves forward and backward with respect to the outer cylinder of the steering column. Then, when the lock piece advances, it engages with the outer cylinder to restrict the rotation of the steering wheel.

  FIG. 1 is a diagram illustrating a steering system 10 according to the present embodiment, and is an explanatory diagram mainly illustrating a configuration of a steering lock mechanism as a lock unit that restricts the rotation of the steering wheel 12.

  The steering system 10 includes a steering wheel 12, a steering shaft 14, a steering column 16, and a universal joint (not shown). The steering wheel 12 includes an annular rim, a hub inserted into the steering shaft 14, and spokes connecting the rim and the hub. The steering wheel 12 is provided with a horn switch. In some cases, a switch such as an air bag device or audio is provided. The steering wheel 12 is engaged with one end of the steering shaft 14 by taper serration and fixed with a nut 14a. As a result, the steering wheel 12 and the steering shaft 14 are configured to rotate simultaneously. A universal joint is provided on the other end side of the steering shaft 14 and is connected to the steering gear box side.

  The steering column 16 includes an outer tube (outer cylinder) 18 and an inner tube (inner cylinder) 20, and serves to support the steering shaft 14 with the outer tube 18 and the inner tube 20. The inner tube 20 rotates with the steering shaft 14 housed inside. The outer tube 18 rotatably accommodates an inner tube 20 that rotates integrally with the steering shaft 14 and is fixed to a vehicle frame or the like via a bracket 24. Further, the fixed side of the steering wheel 12 of the steering column 16 is covered with a column cover 22. Various switches such as an ignition key switch are arranged on the column cover 22.

  Although a detailed illustration is omitted, the steering system 10 is provided with an impact absorbing structure. For example, in the case of a collision accident, the shock absorbing structure is designed to reduce the driver's injury. When the vehicle body is damaged (primary impact) at the time of collision, the steering system 10 jumps out to the driver side and damages the driver. Prevent giving. Further, it has a function of mitigating damage when the driver collides with the steering wheel 12 (secondary impact) due to inertia at the time of collision. The impact energy is absorbed by compressing and deforming the steering shaft 14 or the steering column 16 in the axial direction. The steering shaft 14 is divided into two parts to enable this compression deformation, but it is joined by serrations and fixed by a resin pin or the like so that the rotational torque of the steering wheel 12 can be satisfactorily transmitted in a steady state. It has become. When the first impact occurs, the resin pin is broken, the steering shaft 14 is contracted in the axial direction, and the entire steering system 10 is mitigated from jumping out to the rear of the vehicle.

  Further, when the shock is absorbed by the steering column 16, the shock energy is absorbed by sliding the outer tube 18 and the inner tube 20 to contract each other. For example, a metal ball held by a resin gauge is press-fitted between the outer tube 18 and the inner tube 20. When the steering column 16 receives a compressive force at the time of impact, the metal ball moves while forming a groove in the tube, and the outer tube 18 and the inner tube 20 are contracted to each other. The impact energy is absorbed by the resistance force generated at this time. The steering column 16 is provided with a tilt mechanism, a telescopic mechanism, and the like in addition to the above-described shock absorbing structure.

  The steering system 10 configured as described above includes a steering lock mechanism as a device for preventing the vehicle from being stolen. In the case of this embodiment, in order to shorten the steering column 16 while securing the sliding allowance of the outer tube 18 and the inner tube 20 during the operation of the above-described shock absorbing structure, the lock means constituting the steering lock mechanism is used as the steering. Arranged inside the wheel 12. The lock means can be composed of a lock piece 26 that can be moved back and forth and a motor 28 that moves the lock piece 26 back and forth.

  FIG. 2 is an enlarged view centering on the steering lock mechanism. The lock piece 26 that moves forward and backward can advance into the column cover 22, constitutes the steering column 16 inside the column cover 22, and engages with the outer tube 18 fixed to the frame of the vehicle. The rotation of the steering wheel 12 is restricted. As shown in FIG. 2, the outer tube 18 extends to the inside of the column cover 22, and a lock plate 30 having a surface substantially orthogonal to the axial direction of the outer tube 18 is fixed to the distal end portion thereof. An engagement groove 30a is formed in the lock plate 30 to receive the lock piece 26 that has advanced. The engagement groove 30a can have a shape corresponding to the shape of the lock piece 26. For example, the engagement groove 30a can be a simple circular hole, but may be a square groove or an elliptical groove. The outer tube 18 is made of, for example, an iron material, and can reliably and stably regulate the rotation of the steering wheel 12 when the lock piece 26 is inserted into the engagement groove 30a.

  The motor 28 is energized based on, for example, the ignition key being removed from the key cylinder, and advances the lock piece 26 into the column cover 22 to realize the engagement between the lock piece 26 and the engagement groove 30a. The rotation of the steering wheel 12 is locked. In addition, when the ignition key is inserted into or inserted into the key cylinder and is turned on, power is supplied, and the lock piece 26 is retracted from the column cover 22 to release the engagement between the lock piece 26 and the engagement groove 30a. The motor 28 is energized only during the advance / retreat operation of the lock piece 26. After the advancement or retraction is completed, the advance / retreat position is preferably maintained by mechanical brake means to suppress power consumption.

  As described above, the motor 28 that requires a large arrangement space among the components constituting the steering lock mechanism is arranged in the steering wheel 12 to secure the sliding margin of the steering column 16 that sufficiently functions the shock absorbing structure. However, it becomes possible to reduce the space on the steering column 16 in which the conventional motor is arranged, and the steering column 16 can be shortened. When shortening can be performed while maintaining the conventional function of the steering column 16, it is possible to reduce the size of the vehicle and increase the cabin space. Further, when the steering column 16 is not shortened as a reverse idea, the sliding margin of the steering column 16 can be further increased, and the shock absorbing performance can be further improved. Further, when the steering column 16 is not shortened, it is possible to arrange another mechanism, and the space can be effectively used. In the case where a steering lock mechanism including a motor or the like is disposed on the steering column 16 as in the prior art, it is necessary to provide a structure that prevents the steering lock mechanism from contacting the driver's knee or the like when a vehicle collision occurs. However, in this embodiment, since the motor 28 of the steering lock mechanism is housed inside the steering wheel 12, the above-described measures for hitting the knee are not required, reducing the number of parts and expanding the space around the steering column 16. It can be done easily.

  FIG. 3 is a diagram for explaining another configuration of the steering lock mechanism, and is an enlarged view centering on the steering lock mechanism as in FIG. 2. In the case of FIG. 3 as well, the locking means includes a lock piece 26 that can be moved forward and backward, and a motor 28 that moves the lock piece 26 forward and backward. In the case of FIG. 2, the engagement between the lock piece 26 and the outer tube 18 is performed inside the column cover 22, but in the case of the configuration in FIG. 3, the engagement between the lock piece 26 and the outer tube 18 is performed on the steering wheel 12. Implemented internally. Therefore, the outer tube 18 extends to the inside of the steering wheel 12. Further, the advancing / retreating direction of the lock piece 26 faces the radial direction of the steering wheel 12.

  By engaging the outer tube 18 and the lock piece 26 inside the steering wheel 12, the lock piece 26 and the engagement groove 30a are difficult to see from the outside. Unauthorized acts of extracting the lock piece 26 can be prevented. In the case of the configuration of FIG. 2, a gap is required between the column cover 22 that is a fixed body and the steering wheel 12 that is a rotating body. The lock piece 26 is advanced and retracted across the gap. Therefore, the lock piece 26 that moves forward and backward can be seen from this gap. As a result, the above-described fraud may be possible. Therefore, when the lock piece 26 and the outer tube 18 are engaged on the column cover 22 side as shown in FIG. 2, the steering wheel is covered so as to cover the gap formed between the steering wheel 12 and the column cover 22. 12 or the column cover 22 preferably protrudes from the cover.

  In the case of the example of FIG. 3, the lock piece 26 enters the engagement groove 30 a formed on the side surface of the outer tube 18 extending to the inside of the steering wheel 12. It is not necessary to form the plate 30, and the manufacturing cost of the outer tube 18 can be reduced. In the case of FIG. 3, the diameter of the outer tube 18 may be constant as long as the distal end of the outer tube 18 is enlarged in diameter, as long as the rotation of the steering wheel 12 performed at the time of unlocking is not hindered.

  As shown in FIG. 3, even when the engagement between the lock piece 26 and the outer tube 18 is performed inside the steering wheel 12, the advance / retreat direction of the lock piece 26 is set to the axial direction of the outer tube 18 as in FIG. be able to. In this case, a lock plate 30 similar to that shown in FIG. 2 may be formed at the distal end portion of the outer tube 18 that extends inside the steering wheel 12.

  As shown in FIG. 4, the general steering wheel 12 includes an annular rim 32, a hub 34 inserted into the steering shaft 14, and spokes 36 connecting the rim 32 and the hub 34. In this case, the spoke 36 often has a “T” shape with the upper part largely cut away in order to ensure the visibility of a combination meter such as a speedometer during straight traveling. In this case, since the center of gravity of the spoke 36 is deviated from the center of the rim 32, a sense of incongruity due to eccentricity may be felt during the rotation operation. For this reason, for example, a weight 38 is arranged on the rim 32 on the side where the spoke 36 does not exist, and the center of gravity of the entire steering wheel 12 is moved almost to the center to suppress a sense of incongruity due to eccentricity. On the other hand, in the case of the present embodiment, since the motor 28 is disposed in the steering wheel 12, the motor 28 functions as a weight and can be used for adjusting the center of gravity when the “T” -shaped spoke 36 is used. it can. As a result, the weight 38 can be eliminated and the number of parts can be reduced.

  Further, when a steering lock mechanism is disposed on the steering column 16 as in the prior art, it is necessary to prepare a dedicated steering lock mechanism depending on the form of the steering column 16. On the other hand, by incorporating the steering lock mechanism in the steering wheel 12 as in this embodiment, the steering lock mechanism can be applied to the steering column 16 regardless of the form of the steering column 16. That is, the steering lock mechanism can be shared, which contributes to the standardization of components.

  In the steering system 10 described above, the example in which the motor 28 is used as the drive source of the lock piece 26 has been described. However, the drive source of the lock piece 26 is arbitrary, and a cam mechanism, an electromagnetic solenoid, or other drive source is used. A mechanism may be used, and the same effect can be obtained.

  The configuration of the steering system 10 shown in the present embodiment is an example. That is, as long as the lock means is built in the steering wheel 12 and the lock piece 26 that advances and retreats engages with the outer tube 18 and restricts the rotation of the steering wheel 12, other configurations can be arbitrarily changed, The same effects as those of the above-described embodiment can be obtained.

It is explanatory drawing explaining the structure of the steering lock mechanism of the steering system which concerns on this embodiment. It is an enlarged view centering on the steering lock mechanism of the steering system which concerns on this embodiment. It is an enlarged view centering on the other steering lock mechanism of the steering system which concerns on this embodiment. It is explanatory drawing explaining the balance state of the steering wheel of the steering system which concerns on this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Steering system 12 Steering wheel 14 Steering shaft 16 Steering column 18 Outer tube 20 Inner tube 22 Column cover 24 Bracket 26 Lock piece 28 Motor 30 Lock plate 30a Engaging groove 32 Rim 34 hubs, 36 spokes.

Claims (4)

A steering wheel that rotates to steer the vehicle;
A steering shaft that fixes the steering wheel to the tip and transmits the rotational force of the steering wheel;
An inner cylinder that is formed on an outer periphery of the steering shaft and rotates together with the inner cylinder, and is fixed to a fixed portion of the vehicle;
A locking means that is built in the steering wheel and includes an advanceable / retractable locking piece that engages with the outer cylinder and restricts rotation of the steering wheel;
A steering system comprising:   The said outer cylinder is extended to the inside of the said steering wheel, The said locking means implements engagement of the said locking piece and the said outer cylinder inside the said steering wheel. Steering system.   The steering system according to claim 2, wherein the lock piece advances and retreats in a diameter direction of the steering wheel.   The steering system according to any one of claims 1 to 3, wherein the outer cylinder has an engagement groove that engages with the lock piece.

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