JP2008168746A - Vehicular steering system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the practicality of a steering system by devising mounting structure of an airbag device. <P>SOLUTION: The storage portion 146 of a container 140 storing an airbag 142 is supported by a tube provided on a vehicle body by supporting members 148, 150 to be positioned on a driver side of a steering wheel 20. When operation is carried out while exceeding a range wherein the supporting members interfere with an arm 132 supporting a grip 134 of the steering wheel, a mechanism 160 releasing fixing to the tube by the supporting members is provided. In a comparatively small operation range wherein the supporting members does not interfere, the deploying airbag is not deflected regardless of the operation amount of the steering wheel. It is possible to cope with the expansion of the operation range. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a steering system equipped in a vehicle, and more particularly, to a steering system characterized by a mounting structure of an airbag device disposed on a driver side of a steering operation member.

In the event of a vehicle collision, the driver may collide with a steering operation member such as a steering wheel, and in order to reduce the impact received by the driver due to the secondary collision, A bag device is provided. An airbag device is configured to include an airbag that is deployed at the time of a vehicle collision and a container that accommodates the airbag in a folded state. The container is generally described in the following patent document. As shown, it is fixedly attached to the steering operation member.
Japanese Patent Laid-Open No. 11-342819 Japanese Patent Laid-Open No. 11-245759

  The airbag is not necessarily symmetrical vertically or horizontally in the deployed shape. For example, in the case where the steering operation member is mounted with an inclination so that the upper portion thereof is located on the vehicle front side with respect to the lower portion, the upper portion is thickened in consideration of the collision angle of the driver with the steering operation member. The lower part may be formed in a thin shape. When mounting an airbag device having such an airbag having shape anisotropy on a steering operation member, when the airbag is deployed in a state where the steering operation member is rotated, the airbag is set. The posture is different from the posture, in other words, deflected and deployed. An airbag that is deflected and deployed in this way may not be able to fully exhibit impact relaxation performance. Therefore, devising the attachment structure of the airbag device leads to improvement of the practicality of the vehicle steering system. This invention is made | formed in view of such a situation, and makes it a subject to provide the steering system for vehicles with high practicality.

  In order to solve the above problems, a vehicle steering system according to the present invention has a steering operation for supporting an airbag device on a part of a vehicle body and positioning the airbag device on a driver side of a steering operation member. A support member arranged so as to extend through a space through which the arm portion holding the grip portion of the member can pass is adopted, and fixing of one end portion of the support member to a part of the vehicle body is performed. The steering operation member is configured to be released when the steering operation member interferes with the arm portion.

  In the vehicle steering system of the present invention, since the airbag device is fixedly supported by a part of the vehicle body by the support member, the operation amount of the steering operation member is reduced in a relatively small operation range where the support member does not interfere. Regardless, the deployed airbag will not deflect. Therefore, in the operating range, the impact mitigation performance of the airbag is sufficiently exhibited. On the other hand, when the steering operation member is operated beyond the operation range, the support member is released from being fixed to a part of the vehicle body, so that smooth operation is possible even in a relatively large operation range. Become. By utilizing such characteristics, it is possible to construct a vehicle steering system with high practicality.

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which some constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention. The following items (1) to (9) correspond to claims 1 to 9, respectively.

(1) A rotation center portion rotatably held by a part of the vehicle body, and one or more arm portions having one end portion connected to the rotation center portion and extending in a direction intersecting the rotation axis of the rotation center portion; A steering operation member that is held at the other end of the one or more arm portions and has one or more grip portions that are gripped by the driver, and is rotated to steer the wheels;
An airbag device having an airbag that is deployed in the event of a vehicle collision, and an airbag container that accommodates the airbag;
One end portion is attached to a part of the vehicle body and extends through a space through which the one or more arm portions can pass in rotation of the steering operation member, and the airbag container is attached to the other end portion. A support member that supports the airbag container so as to be positioned on the driver side of the rotation center portion of the steering operation member;
In the case where one end of the support member is fixed to a part of the vehicle body, and the support member interferes with one of the one or more arm portions of the steering operation member to restrict the rotation operation of the steering operation member. A vehicle steering system comprising: a support member fixing mechanism having a function of releasing the fixing of one end of the support member to a part of the vehicle body.

  According to the steering system of the aspect of this section, the airbag apparatus is configured such that an instrument panel (hereinafter sometimes abbreviated as “instrument panel”), a reinforcing member thereof, and the like are disposed through the support member. Usually, the support member is fixed to a part of the vehicle body at one end thereof. Therefore, unlike the case where the airbag device is fixed to the steering operation member (hereinafter, sometimes simply referred to as “operation member”), the operation range in which the support member does not interfere with the arm portion of the operation member (hereinafter referred to as “non-operational member”). The air bag is not deflected and deployed in the “interference range” in some cases. Therefore, according to the aspect of this section, it is possible to effectively mitigate the impact of the secondary collision on the operation member of the driver within a certain range of operation. On the other hand, when the operation member is operated beyond the non-interference range, the support member is released from being fixed to a part of the vehicle body at one end thereof, and thus a large range of steering operation is possible. .

  The aspect of this section is a so-called steer-by-wire type steering system, that is, the steering device that steers the wheel and the operating member are not mechanically connected, and the rolling device is not relied on to the force applied to the operating member. It is suitable for a system that realizes wheel steering according to the operation of the operation member by the power of the drive source of the rudder device, and is also a so-called VGRS (variable gear ratio steering) system, that is, the operation member and the steering device. The system is suitable for a system in which a predetermined actuator is provided between the control member and the ratio of the wheel turning amount to the operation amount of the operation member can be changed by the operation of the actuator. Since these systems can steer relatively large wheels in a relatively small operating range, for example, it can be configured to allow normal steering operation in a non-interference range. By configuring in this way, it is possible to keep the impact mitigation characteristics of secondary collisions in the range of normal steering operation favorable. In these systems, when the drive source of the steering device fails, the wheels need to be steered by the force applied to the operation member, so that the steering beyond the non-interference range is considered in view of facilitating the steering operation. Operation is enabled. According to the aspect of this section, it is possible to cope with such an expansion of the operation range.

  Note that the aspect of this section is also effective in an ordinary system that is not the steer-by-wire system, the VGRS system, or the like. Usually, the impact mitigation of the secondary collision by the air bag is particularly required in the case of the vehicle collision under the situation where the vehicle is traveling at a high speed. Generally, when the vehicle is traveling at high speed, the operation range is relatively small. For this reason, if the aspect of this section is adopted for a system having a configuration in which the range falls within the non-interference range, at least in the range where the impact reduction by the airbag is particularly required, the impact reduction characteristics are improved. It is possible to keep.

  The shape of the “steering operation member” in the aspect of this section is not particularly limited. For example, like an ordinary steering wheel, it may have an annular grip portion and one or a plurality of spoke-shaped arm portions that connect the grip portion and the rotation center portion. . Moreover, it may replace with an annular grip part and may have a shape having a grip part in which a part of the annular part is missing. Also, a shape having a plurality of grip portions (for example, a pair of grip portions operated by each of the left and right hands), each having a plurality of arm portions connecting the one grip portion and the rotation center portion. It may be. The steering operation member may have a structure in which the rotation center portion has a shaft like a so-called steering shaft, and the shaft is rotatably held by a part of the vehicle body. The center portion may be formed into a ring shape, a cylindrical shape, or the like, and the rotation center portion may be rotatably held by a fixed shaft included in a part of the vehicle body. Furthermore, the rotation center portion may be fixedly connected to a rotatable shaft or indirectly held to a part of the vehicle body via the shaft. Good. Incidentally, the steering operation member may be one in which any two or more of the grip part, the arm part, and the rotation center part are formed integrally with each other, and is configured by assembling them. May be.

  In addition, “a space through which one or more arm portions pass in the rotation of the steering operation member” means, in other words, an annular shape defined by a locus drawn by one or more grip portions by the rotation operation of the operation member and the rotation center portion. It is space. The support member is disposed so that this space extends from a part of the vehicle body to the driver of the operation member. For example, at the end that extends to the driver side, the airbag device, A container is fixedly attached. Since the aspect of this section is such a structure, when the support member is fixed to a part of the vehicle body at one end thereof, the support member interferes with the rotation of the arm portion by the rotation operation of the operation member. The steering operation is limited to the range to be performed. In the aspect of this section, in order to cancel the restriction of the steering operation, the fixing of the support member to a part of the vehicle body is released.

  In this aspect, when the support member is released, the support member may be configured to be detached from a part of the vehicle body, while the support member is maintained attached to a part of the vehicle body. It may be configured to operate so as to allow operation of the operation member exceeding the non-interference range. In the latter case, as described later, the support member may be configured to move along a predetermined trajectory, such as rotating around the rotation axis of the operation member. Further, after the support member is once fixed, when the operation member is operated again within the non-interference range, the support member may be fixed again at the original position. Such a configuration can be easily realized, for example, by adopting a structure in which the support member is fixed to a part of the vehicle body by elastic force, as will be described later.

  (2) An operation range in which the steering system changes a rotation operation range of the steering operation member between a range in which the support member does not interfere with any of the one or more arm portions and a range exceeding the range. The vehicle steering system according to item (1), further including a changing device.

  For example, in the case of the above-described steer-by-wire system, VGRS system, etc., the aspect of this section is such that normal steering operation is performed within the non-interference range, and the turning device, VGRS actuator, etc. The operation range can be expanded. Since such a configuration can be realized, the aspect of this section is suitable for these steer-by-wire systems, VGRS systems, and the like. Specifically, the operation range changing device is a mechanical stopper that defines the operation range of the operation member (the operation range of the operation member may be defined as a result by limiting the steering range). Two types can be provided, and the structure can be made to selectively function them. In addition, a device that includes a motor capable of applying an operation reaction force to the operation member, regardless of a mechanical stopper, and that restricts the operation range by increasing the force of the motor may be used.

  (3) The vehicle according to (1) or (2), wherein one end portion of the support member is attached to a part of the vehicle body in a state of being rotatable around a rotation axis of a rotation center portion of the steering operation member. Steering system.

  According to the aspect of this section, even when the fixing of the one end portion of the support member to a part of the vehicle body is released, the support member rotates around the rotation axis of the operation member. It rotates at the position of the operating member on the driver side. Therefore, even when the vehicle collides when steering is performed beyond the non-operation range, the airbag can be deployed at a predetermined position, although it does not assume the set posture.

  (4) When the support member fixing mechanism interferes with one of the one or more arm portions of the steering operation member of the support member, the one or more arm portions of the support member fixing mechanism are rotated along with the rotation operation of the steering operation member. 4. The vehicle steering system according to any one of items (1) to (3), wherein any one of them pushes the support member to release the fixing of one end of the support member.

  The aspect of this section is an aspect configured so that the fixing of the support member is released by the operation force applied to the operation member when the steering operation exceeding the non-interference range is performed. According to the aspect of this section, it is possible to release the fixing of the one end of the support member with a simple structure without requiring a separate driving force.

  (5) The support member fixing mechanism is fixedly engaged with both a part of the vehicle body and one end portion of the support member, and one of the one or more arm portions is broken by a force pressing the support member. The vehicle steering system according to the item (4), further including a breaking engagement member.

  In this mode, the support member fixing mechanism has a member that breaks or breaks when a large force is applied beyond a certain level, such as a so-called shear pin. It is the aspect comprised so that it might fix to. According to the aspect of this section, the supporting member can be fixed at one end by a simple mechanism, and the fixing can be released.

  (6) The support member fixing mechanism fixes one end of the support member to a part of the vehicle body by a frictional force generated between them, and one of the one or more arm portions pushes the support member. The vehicle steering system according to (4) or (5), wherein when the frictional force is overcome, the fixing of one end of the support member to a part of the vehicle body is released.

  The aspect of this term is also an aspect in which the support member can be fixed and the fixation can be released by a relatively simple mechanism, similarly to the aspect in which the previous engagement member is employed. The support member fixing mechanism in the aspect of this section includes, for example, a groove formed on one of a part of the vehicle body and one end of the support member and functioning as a guide, and a protrusion formed on the other and fitted in the groove. In addition, when the projection is about to move along the groove, a predetermined frictional force can be generated between a part of the vehicle body and one end of the support member. With such a configuration, once the operation exceeding the non-interference range is performed, by applying a certain amount of operation force, the support member is allowed to move along the groove, and the operation member in a predetermined direction is Operation becomes possible.

  (7) The support member fixing mechanism includes an elastic member that fixes one end portion of the support member to a predetermined position in a part of the vehicle body by its own elastic force, and any one of the one or more arm portions is a support member. The vehicle according to any one of (4) to (6), wherein when the force that pushes over the elastic force overcomes the elastic force, the one end of the support member is released from being fixed to a part of the vehicle body. Steering system.

  The aspect of this term is also an aspect in which the support member can be fixed and released by a relatively simple mechanism, similar to the aspect using the previous engaging member and frictional force. The support member fixing mechanism in the aspect of this section has, for example, a spring as an elastic member, and positions one end of the support member at a part of the vehicle body by the elastic force of the spring, and resists the elastic force. When the applied force is applied, it is possible to adopt a configuration that allows variation in the position of one end of the support member. The “predetermined position” is a concept including a predetermined rotational position when the support member rotates.

  (8) The support member fixing mechanism has a structure in which an elastic force of the elastic member increases in accordance with an increase in a variation amount from the predetermined position of one end portion of the support member. Vehicle steering system.

  According to the aspect of this section, even after the fixing of the support member is released, the elastic force corresponding to the amount of variation from the fixing position in the operation of the support member is applied to the one end portion of the support member. By using such an elastic force, the support member can be easily returned to the position where the support member is fixed. Note that the “variation amount of the support member” is a concept including a rotation variation amount in the case of the rotation operation, that is, a rotation amount.

  (9) A rotation center portion of the steering operation member has a shaft, and the shaft is rotatably held by the holding member in a state of being inserted into a generally cylindrical holding member constituting a part of the vehicle body, The vehicle steering system according to any one of (1) to (8), wherein a support member is attached to an outer peripheral portion of the holding member.

  For example, the aspect of this section relates to a steering system including a so-called steering column. In the aspect of this section, the rotation center portion includes a so-called steering shaft as a shaft or a part thereof, and a part of the vehicle body has a steering tube that rotatably holds the steering shaft. Or it will be comprised including a part of it. A general steering system is often configured to include a steering column. In that sense, according to the aspect of this section, a highly versatile steering system is realized. In addition, the aspect of this section can easily realize the aspect described above, that is, the aspect in which one end portion of the support member can be rotated around the rotation axis of the operation member.

  Hereinafter, embodiments of the claimable invention will be described in detail with reference to the drawings. In addition to the following examples, the claimable invention is implemented in various modes including various modifications and improvements based on the knowledge of those skilled in the art, including the mode described in the above [Aspect of the Invention] section. can do.

≪Overall structure of steering system≫
As shown in FIG. 1, the steering system of the present embodiment is a steer-by-wire type steering system. This system is broadly divided into a steering operation device (hereinafter sometimes abbreviated as “operation device”) 10, a steering device 12 for turning wheels, a connecting device 14 for connecting them, An electronic control unit (hereinafter may be abbreviated as “ECU”) 16 as a control device is included.

  The operating device 10 is rotatably held in a state in which the handle 20 operated by the driver, a steering shaft (hereinafter abbreviated as “shaft”) 22 having the handle 20 attached to one end, and the shaft 22 are inserted. A tube 24 serving as a holding member, and an operation reaction force applying device 26 that is fixedly connected to the vehicle front side end portion of the tube 24 and applies an operation reaction force to the handle 20 via the shaft 22. ing. As will be described later, the operation device 10 is fixed to a part of the vehicle body, more specifically, to the reinforcement that is a reinforcing member of the instrument panel, in the operation reaction force applying device 26. The operating device 10 includes an airbag device 30 and a sustainer 32 for attaching the airbag device 30 to the tube 24.

  The steering device 12 is a drive source that drives the steering rod 40 in the axial direction, the steering rod 40, the housing 42 that holds the steering rod 40 so as to be movable in the axial direction, and the housing 42. A steered motor 44 and a pair of link rods 46 connected to both ends of the steered rod 40 via flexible joints are configured. The tip of each link rod 46 is connected to an arm of a steering knuckle 50 that rotatably holds the wheel 48 via another flexible joint. The steered rod 40 is formed with a male screw, and the housing 42 is provided with a nut that engages with the male screw. The steered motor 44 moves the steered rod 40 in the axial direction by rotating the nut to steer the wheels 48. In addition, a rack is formed on the steered rod 40, and a pinion shaft 52 on which a pinion that meshes with the rack is held in the housing 42 so as to be rotatable in a manner that projects one end from the housing 42. ing. As will be described in detail later, the steering device 12 can also steer the wheels 48 by rotating the pinion shaft 52.

  The coupling device 14 is a device mainly composed of the electromagnetic clutch 60. An input pulley 62 is attached to the input portion of the electromagnetic clutch 60, and the input pulley 62 and an output pulley (see FIG. 2) attached to the shaft 22 are connected by a belt 64 so as to be able to transmit rotation. . On the other hand, an output roller 66 is attached to the output unit, and the output roller 66 and the input roller 68 integrated with the pinion shaft 52 of the steering device 12 are connected by a wire 70 so as to be able to transmit rotation. ing. The electromagnetic clutch 60 realizes a state in which the operating force is not transmitted between the operating device 10 and the steering device 20 by allowing relative rotation between the input pulley 62 and the output roller 66 in the excited state. By prohibiting relative rotation between the input pulley 62 and the output roller 66 in the demagnetized state, a state in which the operating force from the handle 20 can be transmitted to the steering device 20 is realized.

≪Structure of operation reaction force applying device≫
As shown in FIG. 2, the operation reaction force applying device 26 includes a rear chamber 80 located on the vehicle rear side (right side in the drawing), and a front chamber 82 located on the vehicle front side (left side in the drawing). The above-described shaft 22 is rotatably held by the housing 84 in a state of passing through the rear chamber 80. A right end (not shown) of the shaft 22 in the drawing is connected to the handle 20. In the rear chamber 80, the shaft 22 supports a cylindrical spring case 86 so as to be rotatable in a state of passing through the spring case 86. Inside the spring case 86, a pair of torsion coil springs (hereinafter simply referred to as “springs”) 88 is provided so as to be externally fitted to the shaft 22. The pair of springs 22 are wound in opposite directions, and one end of each pair is fixed to the inner surface of the spring case 86 and the other end is fixed to the large-diameter portion 90 of the shaft 22. In the state shown in the figure, the pair of springs 88 are twisted together, and their torsional reaction forces are in a balanced state. Incidentally, in this state, the handle 20 is located at a neutral position corresponding to the wheel turning neutral position, that is, at the neutral rotation position.

  A solenoid 92 is provided on the outer periphery of the housing 84. The rod 94 of the solenoid 92 extends into the rear chamber 80, and an engagement plate 96 is attached to the tip portion thereof. When the solenoid 92 is in a demagnetized state, the engagement plate 96 is separated from the outer peripheral surface of the spring case 86, and when the shaft 22 rotates, the spring case 86 rotates integrally with the shaft 22. To do. That is, the rotation of the spring case 86 is allowed. On the other hand, when the solenoid 92 is energized, the engagement plate 96 moves forward and contacts the outer peripheral surface of the spring case 86. The engagement plate 96 is subjected to a surface treatment that enables generation of a large frictional force, and the rotation of the spring case 86 is prohibited by the frictional force. When the shaft 22 is rotated by the operation of the handle 20 in a state where the rotation of the spring case 86 is prohibited, the balance of the torsional reaction force of the spring 88 is lost, and the reaction force against the operation of the handle 20 is driven via the handle 20. Communicated to the person. That is, the operation reaction force applying device 26 has an elastic force-based operation reaction force generation mechanism that generates an operation reaction force based on the elastic force of the elastic member.

  The large-diameter portion 90 of the shaft 22 is provided with a protruding portion 100 protruding from the outer periphery. On the other hand, a groove 102 through which the protruding portion 100 can pass is formed in the circumferential direction on the inner peripheral surface of the spring case 86. It is extended. In the state where the rotation of the spring case 86 is prohibited, the protrusion 92 is movable in the groove 102 as the handle 20 is rotated. However, the operation amount of the handle 20 (from the neutral rotation position) The protrusion 100 comes into contact with the end of the groove 102. Thereby, the range of the rotation operation of the handle 20 is limited. That is, the operation reaction force application device 26 has an operation range restriction mechanism. Incidentally, when the rotation of the spring case 86 is allowed, the protrusion 100 does not contact the end of the groove 102, and the operation range is not restricted by the operation range restriction mechanism. Due to such a structure, the operation reaction force imparting device 26 functions as an operation range changing device including an operation range control mechanism and a mechanism for switching between prohibition and allowance of rotation of the spring case 86. -ing

  In the front chamber 82, the output pulley 104 described above is attached to the shaft 22 so as not to be relatively rotatable. A reaction force motor 106 is attached to the housing 84. The reaction force motor 106 can apply a rotational force to the shaft 22 through the gears 108 and 110. That is, the operation reaction force applying device 26 has a motor force-based operation reaction force generation mechanism that generates an operation reaction force based on the force of the reaction force motor 106. The rotation amount (rotation angle) of the shaft 22 is detected by the rotation angle sensor 116 via the gears 112 and 114. The rotation angle sensor 116 functions as an operation amount sensor for detecting the operation amount of the handle 20.

≪Composition of handle and airbag device≫
As shown in FIGS. 3 to 7, the handle 20 is fixedly connected to the end portion of the shaft 22, and forms a rotation center portion of the handle 20 together with the shaft 22 (shaft). A pair of handle arms (hereinafter sometimes simply referred to as “arms”) 132 that extend in opposite directions and function as arm portions, and are connected to and supported by a pair of arms 132, respectively. And a pair of functioning handle grips (hereinafter simply abbreviated as “grips”) 134. The boss 130, the pair of arms 132, and the pair of grips 134 are integrally formed.

  More specifically, the boss 130 has a through hole 136, and the shaft 22 is serrated in the through hole 136. A male screw formed at the tip of the shaft 22 and a nut 142 that is screwed into the male screw are provided. Utilizing this, the boss 130 is fastened and fixed to the shaft 22. 3 to 7 all show a state in which the handle 20 is located at the operation neutral position. In this state, the pair of arms 132 are moved away from the boss 130 in opposite directions, that is, Each extends in the left-right direction. Each arm 132 is bent and extended toward the rear of the vehicle from a position where it extends to some extent, and has a shape that extends again in the left-right direction at a position where it extends to some extent. Each of the pair of grips 134 is integrated with the corresponding one of the pair of arms 132 at the tip of the portion of the pair of arms 132 that extends again in the left-right direction. Each of the pair of grips 134 is formed in an arc shape, and they are arranged along a circle that is centered on the axis of the shaft 22 and that is perpendicular to the axis, and on the opposite side of the circle. It is arranged to be located in.

  The airbag device 30 includes an airbag container (hereinafter sometimes simply referred to as “container”) 140, an airbag 142 that is folded and accommodated therein, and an inflator 144 that deploys the airbag 142. It is configured (see FIG. 4). The container 140 has a generally short cylindrical shape and has a housing portion 146 that houses the airbag 142 and the inflator 144, and an extending portion 148 that extends from the housing portion 146. The extending portion 148 extends from a specific portion located on the vehicle front side of the housing portion 146 at a right angle to a surface located on the vehicle rear side of the housing portion 146.

  The sustainer 32 has an annular portion 150 that forms an annular shape, and a support piece portion 152 that extends from the annular portion 150. The annular portion 150 is attached to the tube 24 via the bearing 154 so as to be rotatable and immovable in the axial direction with the tube 24 inserted. On the other hand, the support piece 152 has a strip shape, and extends upward, is bent at a position extending upward to some extent, and further extends toward the rear of the vehicle. The distal end portion of the support piece portion 152 is fitted into a coupling hole 156 provided in the extension portion 148 of the airbag container 140. That is, in the operating device 10, the container 146 of the container 140 functions as an airbag container, and the airbag container is connected to the vehicle body by the sustainer 32 and the extending part 148 of the container 140 coupled thereto. A support member for supporting the tube 24 functioning as a part is configured. More specifically, the support member is attached to an annular portion 150 of the sustainer 32 as one end of the support member so as to be rotatable about the axis of the shaft 22, and the support member 146, that is, an airbag. The container is supported with respect to a part of the vehicle body in such a posture that the boss 130 of the handle 20 is positioned on the vehicle rear side, that is, on the driver side.

  Further, the tube 24 is provided with a plunger 160. As will be described later, the plunger 160 has a bottomed circular hole and a block-shaped holder 162 fixedly attached to the outer peripheral surface of the tube 24, and a compression accommodated in the circular hole of the holder 162. A coil spring (hereinafter, simply referred to as “spring”) 164 and a plunger rod 166 whose rear end portion is gently fitted in a circular hole of the holder 160 in a state where the spring 164 is compressed are configured. . The holder 162 is attached to the tube 24 so that the distal end of the plunger rod 166 faces the rear of the vehicle, and the distal end of the plunger rod 166 is positioned so as to contact the end surface of the annular portion 150 of the sustainer 32 on the vehicle front side. It has been made. In this state, the spring 162 is compressed, and the plunger rod 166 biases the annular portion 150 toward the rear of the vehicle.

  The end face of the annular portion 150 of the sustainer 32 is formed so that the upper half of the circumference inclines toward a specific location in the state shown in the figure. Speaking flatly, it is a surface that is generally V-shaped toward the rear of the vehicle (hereinafter, this portion of the end surface is referred to as “rod contact surface 168”). As a result, as shown in FIG. 5, the annular portion 150 is positioned by the urging force of the plunger 160 so that the tip of the plunger rod 166 is positioned at the most depressed portion of the rod contact surface 168. That is, the plunger 160 fixes the sustainer 32 and the extended portion 148 of the airbag container 140 constituting the support member so that they are located at a predetermined rotational position by the elastic force of the spring 164 which is an elastic member. It functions as a support member fixing mechanism. In the state where the sustainer 32 is fixed so as to be positioned at the predetermined rotational position, the extended portion 148 of the container 140 and the support piece portion 152 of the sustainer 32 are located at the uppermost position, that is, the axis of the shaft 22. It is located directly above. The rotational positions of the airbag device 30 and the sustainer 32 in this state are predetermined positions, and in the following description, these positions are referred to as the respective reference rotational positions.

  As shown in FIG. 8A, the operating device 10 is attached to the reinforcement 182 of the instrument panel 180, more specifically, to a bracket 184 provided on the operating reaction force applying device 26. In the attached state, the operating device 10 is in a posture in which the axis of the shaft 22 is inclined such that the front side of the vehicle is positioned higher than the rear side of the vehicle. Both the pair of grips 134 of the handle 20 and the surface of the airbag container 140 included in the airbag device 30 on the vehicle rear side are inclined so that the upper side is positioned on the front side of the vehicle relative to the lower side.

  In the event of a vehicle collision, the airbag 142 is deployed as shown in FIG. 8B in order to reduce the impact of the collision on the driver's handle 20. Specifically, the inflator 144 generates high-pressure gas, and the air bag 142 is inflated by introducing the gas into the folded airbag 142. Although not shown, the housing portion 146 of the container 140 is provided with a weak body portion at a specific portion of the outer plate, and the housing portion 146 is damaged and opened in the weak body portion by the expansion of the airbag 142. The airbag 142 is deployed in a predetermined shape.

As can be seen from FIG. 8B, the inclination angle of the upper body of the driver at the time of the secondary collision with the handle 20 and the inclination angle of the handle 20 described above, that is, the pair of grips 134 and the vehicle of the container 140. There is a difference in the inclination angle of the rear surface. In view of this, for the purpose of effective shock mitigation, the deployed airbag 142 is shaped such that the thickness t _U of the upper portion is greater than the thickness t _L of the lower portion. Therefore, the airbag 142 of the airbag device 30 has shape anisotropy, and exhibits high impact mitigation performance when the airbag device 30 is at the reference rotational position described above.

≪Steering system control≫
The control of this steering system is performed by the ECU 16 as described above. As shown in FIG. 1, the vehicle is provided with an ignition switch (IGSw) 200. When the ignition switch 200 is turned on, the electromagnetic clutch 60 of the coupling device 14 is energized and operated. The solenoid 92 of the reaction force applying device 26 is excited. Accordingly, the wheel 48 can be steered by the driving force of the steered motor 44 regardless of the driver's operating force applied to the handle 20, that is, the normal operating state.

  In the normal operation state, the operation amount from the neutral operation position of the handle 20 is acquired by the rotation angle sensor 116, and the turning of the wheel 48 having the steering amount corresponding to the acquired operation amount is performed by the steering device 12. Is done by. Note that the vehicle travel speed is acquired by the vehicle speed sensor (v) 202, and when the vehicle speed is high, the steered amount is adjusted so that the steered amount becomes smaller than when the vehicle speed is low. That is, this steering system is a vehicle speed sensitive system. In the normal operation state, as described above, the operation reaction force applying device 26 applies an operation reaction force having a magnitude corresponding to the operation amount of the handle 20 depending on the elastic force of the spring 88. The Further, the operation speed of the handle 20 is obtained from the change in the detection value of the rotation angle sensor 116, and the operation reaction force is adjusted by the force of the reaction force motor 106 so as to increase the operation reaction force as the operation speed increases.

  When the ignition switch 200 is turned off, the electromagnetic clutch 60 and the solenoid 92 are demagnetized. In addition, when a failure occurs in the power supply for supplying power to the steering system, the ECU 16, the steering motor 44, etc., that is, even in the failure state, the electromagnetic clutch 60 and the solenoid 92 are demagnetized. When they are demagnetized, the operation reaction force is not applied by the operation reaction force applying device 26, and the operation force applied to the handle 20 is transferred to the steering device 12 by the belt 64 and the wire 70. It becomes a state that can be transmitted. Thereby, the wheel can be steered by operating force.

  In the normal operation state, the driver's operation force is not required for the steering of the wheel 48, so that the steering amount becomes large even if the operation amount of the handle 20 is relatively small in consideration of operability. Control is executed. Therefore, the operation range is restricted to be relatively small by the above-described operation range restriction mechanism provided in the operation reaction force applying device 26. Specifically, each of the left and right steering operations is limited to a range of about 45 ° from the neutral operation position. On the other hand, in the failure state, the steering of the wheels 48 depends on the driver's operating force, so that the ratio of the steering amount of the wheels 48 to the operation amount becomes small in order to reduce the operation burden. ing. Therefore, in the failure state, the restriction by the operation range restriction mechanism is released, and the operation range is expanded. Incidentally, the turning device 12 is expanded to a range corresponding to a range in which the turning amount is limited. Specifically, for each of the left and right steering operations, the range is expanded to about 135 °.

  When the vehicle collides, the collision is detected by a collision sensor (C) 204 provided in the front portion of the vehicle, and the airbag apparatus 30 is activated based on the detection. That is, the airbag 142 is deployed by the inflator 144, and the impact of the secondary collision on the driver's handle 20 is effectively mitigated.

≪Relationship between steering wheel operation and airbag device movement≫
In the present steering system, the airbag device 30 is positioned on the driver side of the handle 20 by the support of the sustainer 32. In other words, the container 146 of the container 140 that functions as an airbag container is supported by the support member formed by the sustainer 32 and the extending part 148 of the container 140, so that the container 146 is connected to the handle 20. The boss 130 is disposed on the driver side. The extended portion 148 of the container 140 penetrates the space through which the arm 132 passes when the handle 20 is rotated, that is, the donut-shaped space defined by the locus drawn by the arm 132. Extending in the longitudinal direction of the vehicle. The airbag device 30 is fixed to the reference rotation position by the plunger 160 described above. Therefore, when the driver rotates the handle 20, the extension portion 148 interferes with one of the pair of arms 132 depending on whether the left turn operation or the right turn operation is performed. Become.

  FIG. 9A shows a state when the handle 20 is in the neutral operation position, and FIG. 9B shows a state in which the left turn operation is performed so that the handle 20 and the extending portion 148 of the container 140 are the handle 20. The state at the time of the operation position which interferes with the right arm 132 is shown. The operation range of the handle 20 until the latter state is reached is a non-interference range, specifically, a range of 45 ° from the neutral operation position. Note that the non-interference range is slightly larger than the range limited by the operation range limiting mechanism of the operation reaction force applying device 26 described above. Therefore, in the normal operation state, actually, the interference with the arm 132 of the handle 20 of the extending portion 148 of the container 140 does not occur.

  On the other hand, in the failure state, as described above, the solenoid 92 of the operation reaction force applying device 26 is demagnetized, and the operation range restriction by the operation range restriction mechanism is released. In that case, the operation of the handle 20 beyond the non-interference range is required. In the operation device 10, the airbag device 30 is fixed, that is, the annular portion 150 of the sustainer 32 is fixed to the tube 24 by the elastic force generated by the spring 164 of the plunger 160 as described above. As shown in FIG. 10A, the sustainer 32 is positioned at the reference rotation position, and the airbag device 30 is also positioned at the reference rotation position. When the handle 20 is operated beyond the non-interference range in the failure state, when the operating force in that case exceeds a certain level, the fixation of the sustainer 32 to the tube 24 is released. Specifically, the force by which the arm 132 of the handle 20 pushes the extension portion 148 of the container 140 that interferes with the operating force overcomes the elastic force of the spring 164 and the spring 164 of the plunger 160 is further compressed. In this case, as shown in FIG. 10B, the sustainer 32 rotates around the axis of the shaft 22 and the fixing of the airbag device 30 is released. When the airbag device 30 is unlocked, the arm 132 continues to push the extension portion 148 of the container 140 in accordance with the further rotation operation of the handle 20, as shown in FIG. 9C. Until then, the airbag device 30 is rotated.

  As described above, the rod contact surface 168 provided in the annular portion 150 of the sustainer 32 is generally recessed in a V shape. Therefore, the elastic force of the spring 164 increases in accordance with the amount of rotational fluctuation from the reference rotational position of the sustainer 32, specifically, the annular portion 150 thereof. Therefore, as the operation amount of the handle 20 increases, a large operation force is required. Further, when the driver releases his hand from the handle 20 or when the driver performs a turning operation in the reverse direction, the annular portion 150, that is, the sustainer 32, is caused by the elastic force of the spring 164. The airbag device 30 is returned to the reference rotation position by returning to the reference rotation position.

  As described above, in the failure state, the handle 20 is allowed to rotate until it is restricted by the steering device 20 to steer the wheels 48, and further exceeds the non-interference range by about 90 °. Is performed. The rod contact surface 168 provided in the annular portion 150 has a shape that allows the airbag device 30 to return to the reference rotation position by the action of the elastic force of the spring 164 even at the end of the expanded operation range. ing.

  In the operation device 10, the airbag device 30 is fixed at the reference rotation position in the normal operation state regardless of whether the handle 20 is in any rotation operation position within the operation range. Therefore, even if the airbag 142 is deployed due to a vehicle collision, the airbag 142 is always deployed in a proper posture that is not deflected, that is, in a rotational posture in which the thick portion of the airbag 142 is positioned above and the thin portion is positioned below. As a result, the impact of the secondary collision on the driver's handle 20 can be effectively reduced. When it is necessary to expand the operation range of the handle 20 such as a failure state, the arm 132 is extended by the operation force of the handle 20, more specifically, depending on the operation force. As a result, the operation of the handle 20 exceeding the non-interference range can be easily performed.

  Even when the steering wheel 20 is rotated beyond the non-interference range, the airbag device 30 only rotates around the axis of the shaft 22, and in any direction from the predetermined position. Can not be translated. Therefore, even if the vehicle collides in that case, the airbag 142 is not deployed in the set rotational posture, but is deployed at a predetermined position. It is possible to alleviate the impact caused by the collision sufficiently.

≪Modification≫
A modified example of the steering system, specifically, a modified example of the operating device will be briefly described. In the following modified examples, the same reference numerals are used for components having the same or the same functions as those in the previous embodiments.

  The mechanism for fixing the extending portion 148 of the sustainer 32 and the airbag container 140 to the tube 24 at the reference rotation position, that is, the above-described support member fixing mechanism may have a structure as shown in FIG. it can. In the operation device 10 of the modification shown in this figure, the annular portion 150 is fitted to the tube 24 so that the inner peripheral surface thereof is in direct contact with the outer peripheral surface of the tube 24 without using a bearing. A guide groove 220 formed along one circumference is provided on the outer peripheral surface of the tube 24. On the other hand, the annular portion 150 is fixedly provided with a pin 222 that penetrates a part of the annular portion 150 and has a tip fitted into the guide groove 220. In the operating device 10, the annular portion 150 is fixed to the tube 24 at the reference rotation position by a frictional force generated between the inner peripheral surface of the annular portion 150 and the outer peripheral surface of the tube 24. When the handle 20 is operated beyond the non-interference range, the force by which the arm 132 of the handle 20 pushes the extending portion 148 of the airbag container 140 due to the operating force overcomes the frictional force. By acting on 150, the fixing of the position of the airbag device 30 is released. In the operation of the handle 20 in the non-interference range, the pin 222 is guided by the guide groove 220, and the airbag device 30 rotates around the axis of the shaft 22. In the operation device 10 according to the present modification, after the operation that once leaves the non-interference range is performed, the position where the sustainer 32 is fixed is changed by the frictional force. Even when the operation device 10 according to the present modification is employed, the airbag 142 is deployed in an appropriate posture regardless of the operation position of the handle 20 in the normal operation state.

  The above-described support member fixing mechanism may further have a structure as shown in FIG. In the operating device 10 of another modification shown in this figure, the annular portion 150 of the sustainer 32 is fitted to the tube 24 via the bearing 156, as in the operating device 10 of the previous embodiment. Similarly to the operation device 10 of the modified example, the inner peripheral surface of the annular portion 150 located in front of the vehicle is brought into contact with the outer peripheral surface of the tube 24. In the operating device 10 according to the present modification, pin holes 230 and 232 are formed in the tube 24 and the annular portion 150 of the sustainer 32, respectively, and the pin holes 230 and 234 pass through both of them. The breaking pin 234 is fitted. The break pin 234 functions as a break engagement member that engages both the tube 24 and the sustainer 32, and plays a role of fixing the sustainer 32, that is, the airbag device 30 to the reference rotation position. Further, when an operation exceeding the non-interference range is performed, if the operation force applied to the handle 20 is large to some extent, that is, the force by which the arm 132 of the handle 20 pushes the arm 132 of the airbag container 140 due to the operation force. However, when it becomes a certain size, the breaking pin 234 breaks and the operation is allowed. After the breaking pin 234 is broken, the operation exceeding the non-interference range is performed by the operation force that overcomes the frictional force between the outer peripheral surface of the tube 24 and the inner peripheral surface of the annular portion 150, as in the previous modification. It becomes possible. Incidentally, the frictional force is made smaller than the frictional force generated in the operating device 10 of the previous modification, and an operation exceeding the non-interference range is possible with a relatively small operating force. As in the previous modification, once the operation is performed out of the non-interference range, the position where the sustainer 32 is fixed is changed by the frictional force, and the operation device 10 of the present modification is changed. Even when it is adopted, the airbag 142 is deployed in an appropriate posture in the normal operation state regardless of the operation position of the handle 20.

  Instead of the handle 20 employed in the operating device 10 of the steering system of the previous embodiment, for example, a handle 20 having a shape as shown in FIG. 12 (a) or FIG. 12 (b) can be employed. The handle shown in FIG. 12 (a) has a shape having a pair of arms 132 and a pair of grips 134, similar to the handle 20 employed in the previous embodiment. In contrast, the angle formed by the pair of arms 132 is approximately 90 °, and the respective tips of the arms 132 are connected to the lower ends of the corresponding ones of the pair of grips 134. Further, the handle shown in FIG. 12B has one arm 132 and one grip 134, the grip 134 is generally C-shaped, and the tip of the arm 132 is centered on the circumference of the grip 134. It is connected to the part. In the operation devices 10 of these two modified examples, the non-interference ranges are about 95 ° and about 140 ° in the left and right turning operations, respectively.

It is a figure which shows the whole structure of the steering system which is an Example of claimable invention. It is sectional drawing which shows the operation reaction force provision apparatus which the operating device of the said steering system has. It is a figure which shows the handle | steering-wheel and airbag part of the said operating device in the viewpoint from the left side of a vehicle. It is sectional drawing which shows the handle | steering-wheel and airbag part of the said operating device in the viewpoint from the left side of a vehicle. It is a figure which shows the handle | steering-wheel and the airbag apparatus part of the said operating device in the viewpoint from the upper direction of a vehicle. It is a figure which shows the handle | steering-wheel of the said operating device, and the part of an airbag apparatus in the viewpoint from the back of a vehicle. It is a figure which shows the handle | steering-wheel and airbag part of the said operating device in the AA view of FIG. (a) is a figure which shows the state in which the said operating device was attached to a part of vehicle body, (b) is a figure which shows a mode that the airbag was expand | deployed in the attached state. It is a figure which shows the relationship between the operation position of the handle | steering-wheel in the said operating device, and operation | movement of an airbag apparatus. It is a figure for demonstrating the plunger currently used in order to fix an airbag apparatus to a reference | standard rotation position in the said operation apparatus, and its operation | movement. It is a modification which can be employ | adopted in the said operating device, Comprising: It is a figure which shows the modification about the mechanism for fixing an airbag apparatus to a reference | standard rotation position. It is a figure which shows the modification about the handle | steering-wheel employable in the said operating device.

Explanation of symbols

10: Steering operation device 12: Steering device 14: Connecting device 16: Electronic control unit (ECU) 20: Handle 22: Steering shaft 24: Tube 26: Operation reaction force applying device 30: Air bag device 32: Sustainer 130: Boss 132: Handle arm 134: Handle grip 140: Air bag container 142: Air bag 146: Housing portion 148: Extension portion 150: Ring portion 152: Support piece portion 160: Plunger 164: Compression coil spring 166: Plunger rod 168: Rod contact surface 180: Instrument panel 182: Reinforcement 220: Guide groove 222: Pin 230: Pin hole 232: Pin hole 234: Breaking pin

Claims (9)

A rotation center portion rotatably held by a part of the vehicle body, one or more arm portions whose one end portion is connected to the rotation center portion and extends in a direction intersecting the rotation axis of the rotation center portion, and one or more of them A steering operation member that is held by the other end of the arm portion and that is gripped by the driver and that is rotated to steer the wheels;
An airbag device having an airbag that is deployed in the event of a vehicle collision, and an airbag container that accommodates the airbag;
One end portion is attached to a part of the vehicle body and extends through a space through which the one or more arm portions can pass in rotation of the steering operation member, and the airbag container is attached to the other end portion. A support member that supports the airbag container so as to be positioned on the driver side of the rotation center portion of the steering operation member;
In the case where one end of the support member is fixed to a part of the vehicle body, and the support member interferes with one of the one or more arm portions of the steering operation member to restrict the rotation operation of the steering operation member. A vehicle steering system comprising: a support member fixing mechanism having a function of releasing the fixing of one end of the support member to a part of the vehicle body.   An operation range changing device for changing a rotation operation range of the steering operation member between a range in which the support member does not interfere with any one of the one or more arm portions and a range exceeding the range; The vehicle steering system according to claim 1 provided.   3. The vehicle steering system according to claim 1, wherein one end portion of the support member is attached to a part of the vehicle body in a state of being rotatable around a rotation axis of a rotation center portion of the steering operation member.   When the support member fixing mechanism interferes with any one or more arm portions of the steering operation member of the support member, any one of the one or more arm portions is accompanied by a rotation operation of the steering operation member. 4. The vehicle steering system according to claim 1, wherein the structure is configured such that the fixing of one end of the support member is released by a force pressing the support member. 5.   The support member fixing mechanism is fixedly engaged with both a part of the vehicle body and one end of the support member, and one of the one or more arm portions is broken by a force pushing the support member. The vehicle steering system according to claim 4, further comprising a joint member.   The support member fixing mechanism fixes one end of the support member to a part of the vehicle body by a frictional force generated between them, and the force by which any one or more of the arm portions pushes the support member is the frictional force. 6. The vehicle steering system according to claim 4, wherein when the vehicle is overcome, the fixing of one end portion of the support member to a part of the vehicle body is released.   The support member fixing mechanism includes an elastic member that fixes one end portion of the support member to a predetermined position in a part of the vehicle body by its own elastic force, and one of the one or more arm portions pushes the support member. The vehicle steering system according to any one of claims 4 to 6, wherein when the elastic force is overcome, the one end portion of the support member is released from being fixed to a part of the vehicle body.   The vehicle steering system according to claim 7, wherein the support member fixing mechanism has a structure in which an elastic force of the elastic member increases in accordance with an increase in a variation amount of the one end portion of the support member from the predetermined position. . A center of rotation of the steering operation member has a shaft, and the shaft is rotatably held by the holding member in a state of being inserted into a generally cylindrical holding member constituting a part of the vehicle body. The vehicle steering system according to claim 1, wherein the vehicle steering system is attached to an outer peripheral portion of the holding member.

Images