JP2007062404A - Electric steering lock device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize an electric steering lock device by reducing components, and to reduce operation sound by reducing operation time. <P>SOLUTION: This electric steering lock device 11 is provided with a motor part 17, a shaft 18 and a lock bar main body 21. The motor part 17 is an outer rotor type brushless motor, and a female screw 56 is formed in a rotor yoke 45. In the shaft 18, a male screw 57 is formed and is screwed to the female screw 56. The lock bar main body 21 is movable between a lock position for limiting the rotation of a steering shaft 65 and an unlock position for releasing the limitation of the rotation, and is connected to the shaft 18 via a pin 63. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electric steering lock device.

In recent years, some vehicles include an electric steering lock device as an anti-theft device or the like (see, for example, Patent Document 1). As shown in FIG. 3, the electric steering lock device 71 in Patent Document 1 includes an electric motor 73 and a lock bar 75, and reciprocates the lock bar 75 in the vertical direction by the driving force of the electric motor 73. It has become. Thereby, the lock bar 75 is moved to the lock position or the unlock position, and the steering of the vehicle is brought into the lock state or the unlock state.
JP 2003-276565 A

  By the way, as the electric motor 73 used for the electric steering lock device in Patent Document 1, an inner rotor type DC motor has been often used. The inner rotor type DC motor has a feature that the torque generated by the rotor is relatively small, and the size of the motor itself must be increased in order to increase the motor output. Therefore, in order to reduce the size of the electric steering lock device, it has been considered to reduce the size of the electric motor itself. In this case, in order to maintain the motor output, the electric motor is rotated at a high speed to reduce the gear reduction ratio. It was necessary to enlarge.

  For this reason, in the electric steering lock device 71 in Patent Document 1, a speed reduction mechanism such as a worm wheel 77 is provided between the electric motor 73 and the lock bar 75 to cope with high-speed rotation of the electric motor. It was. However, the provision of the speed reduction mechanism may increase the size and complexity of the device. Furthermore, there is a risk that the greater the motor output, the greater the reduction ratio and the longer the operating time. Further, driving the electric motor 73 at high speed may increase the operating noise.

  The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide an electric steering lock device that is reduced in size by reducing the number of components and that has a short operation time and a low operation noise.

  In order to achieve the above object, the invention according to claim 1 is a lock bar movable to a lock position for restricting rotation of the steering shaft and an unlock position for releasing restriction of rotation of the steering shaft; An electric steering lock device comprising an electric motor for generating a driving force for moving the lock bar between the lock position and the unlock position, wherein the electric motor is an outer rotor type. To do.

The invention according to claim 2 is summarized in that in the electric steering lock device according to claim 1, the electric motor is a brushless motor.
According to a third aspect of the present invention, in the electric steering lock device according to the second aspect of the present invention, the electric steering lock device further includes conversion means for converting the rotational motion of the electric motor into a linear motion in the moving direction of the lock bar. The gist is that the means is a screw mechanism.

  According to a fourth aspect of the present invention, in the electric steering lock device according to the third aspect, the brushless motor includes a stator core on which a coil is wound, and a bearing provided on an inner peripheral surface of the stator core. A rotor yoke supported rotatably with respect to the stator core; and a magnet fixed to the rotor yoke so as to face the coil, and the screw mechanism is provided on the rotor yoke and the lock bar. It is a summary.

  According to a fifth aspect of the present invention, in the electric steering lock device according to the fourth aspect, the rotor yoke has a cylindrical large-diameter portion that supports the magnet, and a diameter smaller than the large-diameter portion. A small-diameter portion having a cylindrical shape fixed to the inside of the rotor yoke, and the screw mechanism includes a female screw provided on an inner peripheral surface of the small-diameter portion of the rotor yoke and a male screw provided on the lock bar. The gist is that it is configured.

According to a sixth aspect of the present invention, in the electric steering lock device according to any one of the second to fifth aspects, the brushless motor includes a hall element that detects the number of rotations of the brushless motor, and a hall element. The gist is provided with a conversion means for converting the position of the lock bar based on the detected number of rotations.
(Function)
Therefore, according to the first aspect of the present invention, when the outer rotor type electric motor is driven, the lock bar has the lock position for restricting the rotation of the steering shaft and the unlock position for releasing the restriction of the rotation of the steering shaft. Moved to. At this time, the electric motor has a larger torque generated by the rotor than the inner rotor type, and the electric motor itself can be downsized without reducing the motor output. Therefore, it is not necessary to rotate the electric motor at a high speed in order to compensate for the decrease in motor output, and it is not necessary to provide a speed reduction mechanism between the lock bar and the electric motor. Furthermore, since the electric motor is not rotated at high speed, the operating noise can be reduced.

  Therefore, according to the second aspect of the present invention, when the outer rotor type brushless motor is driven, the lock bar is moved to the lock position and the unlock position. By using a brushless motor as the electric motor, a mechanical rectification mechanism such as a DC motor is not required, and a simple structure and easy maintenance can be achieved.

  According to the invention described in claim 3, the rotational motion of the electric motor is converted into the linear motion of the lock bar by the screw mechanism. In other words, the space can be converted with a simple structure as compared with the case where a cam, a crank, or the like is employed.

  Therefore, according to the fourth aspect of the invention, when the rotor yoke is rotated, a force that moves in a linear direction is applied to the lock bar via the screw mechanism provided on the rotor yoke and the lock bar. Therefore, the screw mechanism can be easily provided only by performing a process of cutting a screw on an existing rotor yoke or lock bar provided in the electric steering lock device, and there is no need to provide a special new part.

  Therefore, according to the fifth aspect of the present invention, when the rotor yoke is rotated, the rotor yoke is rotated linearly with respect to the lock bar via the female screw provided on the small diameter portion of the rotor yoke and the male screw provided on the lock bar. The power to move to is added. As a result, the rotational movement of the rotor yoke can be converted into the linear movement of the lock bar with a simple structure as compared with the case where the male screw is provided on the rotor yoke side and the female screw is provided on the lock bar side.

Therefore, according to the invention described in claim 6, the conversion means detects the number of rotations of the motor using the hall element normally provided for the motor control of the brushless motor, and the lock bar of the lock bar is detected from the detection result. Convert the position. As a result, it is not necessary to provide a dedicated switch or hall element in order to obtain the position of the lock bar.

  According to the electric steering lock device of the present invention, it is small in size, has few components, has a short operation time, and can reduce the operation sound.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the electric steering lock device 11 mainly includes a casing 12, a housing 14, a substrate 16, a motor portion 17 as an electric motor, a shaft 18 constituting a lock bar, and a lock bar main body 21 constituting a lock bar. As a simple component. The casing 12 includes an upper casing 23 and a lower casing 25. As shown in FIGS. 1 and 2, the upper casing 23 is formed in a shape that combines a cylinder and a rectangular parallelepiped, and is formed in a shape in which the upper surface is closed and the lower surface is opened.

  As shown in FIG. 1, the lower casing 25 is formed in a shape capable of closing the opening on the lower surface side of the upper casing 23, and is attached to the upper casing 23 to thereby form a first substantially cylindrical shape in the housing 14. A housing space 27 and a second housing space 29 having a substantially rectangular parallelepiped shape are formed. The lower casing 25 is formed with a first cylindrical portion 31 that is positioned concentrically with the axis of the first housing space 27 of the upper casing 23 and protrudes toward the upper casing 23. ing.

  Further, the lower casing 25 is positioned concentrically with the axial center of the first housing space 27 and protrudes from the first cylindrical portion 31 toward the upper casing 23 to the second cylindrical portion 32. Is formed. Note that the size of the cross-sectional area of the second cylindrical portion 32 is smaller than the size of the cross-sectional area of the first cylindrical portion 31. The lower casing 25 is formed with a third cylindrical portion 33 that is located concentrically with the axis of the first housing space 27 and protrudes in a direction opposite to the upper casing 23. ing. In addition, the size of the cross-sectional area of the third cylindrical portion 33 is a size between the cross-sectional area of the first cylindrical portion 31 and the cross-sectional area of the second cylindrical portion 32.

  The lower casing 25 is concentrically positioned with the axis of the first accommodating space 27 of the upper casing 23 from the second cylindrical portion 32 to the first cylindrical portion 31 and the third cylindrical portion 33. In this way, the through hole 35 is formed. And this through-hole 35 is formed in the edge part by the side of the 2nd cylinder part 32 so that the cross-sectional area may become small. The housing 14 is made of resin and is provided so as to cover the surface of the lower casing 25 on the side facing the upper casing 23. The housing 14 is formed with a first engagement port 37 having a diameter that matches the second cylindrical portion 32 of the lower casing 25. The housing 14 is provided with respect to the lower casing 25 in a state where the second cylindrical portion 32 penetrates the first engagement port 37.

  The substrate 16 is provided in the casing 12, and a second engagement port 39 having a size that matches the first engagement port 37 of the housing 14 is formed. And the board | substrate 16 is provided so that it may be mounted on the housing 14 in the state by which the said 2nd cylindrical part 32 penetrated the 2nd engagement port 39. As shown in FIG. Various electronic components such as a control device (not shown) as conversion means are mounted on the substrate 16.

The motor unit 17 is an outer rotor type brushless motor, and includes a stator core 41, a coil 43, and a rotor yoke 45. The stator core 41 is fixed to the second cylindrical portion 32 of the lower casing 25 so as to protrude toward the upper casing 23, and is formed in a substantially cylindrical shape. The upper casing 23 is provided so as to be concentric with the first accommodation space 27. The coil 43 is wound around the stator core 41.

  The rotor yoke 45 is housed in the first housing space 27 of the upper casing 23 with a slight gap. The rotor yoke 45 is formed in a shape in which two cylinders having different diameters are concentrically overlapped, and includes a large diameter portion 45a having a large diameter and a small diameter portion 45b having a small diameter. And the part between the large diameter part 45a and the small diameter part 45b is obstruct | occluded cyclically | annularly in the edge part by the side of the upper casing 23, and the edge part by the side of the lower casing 25 is the open state. The rotor yoke 45 has a ball bearing 51, 53 as two bearings interposed between the outer peripheral surface of the small diameter portion 45b and the inner peripheral surface of the stator core 41, so that the stator yoke 41, that is, the lower casing 25 is interposed. And is rotatably supported. The stator core 41 around which the coil 43 is wound is accommodated in an annular space between the large diameter portion 45a and the small diameter portion 45b of the rotor yoke 45.

  A plurality of magnets 54 are attached to the inner peripheral surface of the large-diameter portion 45a of the rotor yoke 45 at positions facing the coil 43 at predetermined intervals in the circumferential direction. With the above configuration, the rotor yoke 45 can be rotated forward and backward by energizing the coil 43. This energization control is performed by a control device or the like provided on the substrate 16. A plurality of Hall elements 55 are provided on the substrate 16 at positions facing the magnets 54 of the motor unit 17. The Hall element 55 is normally provided in a brushless motor and is provided to detect the absolute position by detecting the magnetic force of the magnet 54. A trapezoidal female screw 56 is formed on the inner peripheral surface of the small diameter portion 45 b of the rotor yoke 45. In the present embodiment, the internal thread 56 constitutes conversion means and a screw mechanism.

  The shaft 18 is formed in a cylindrical shape on the upper casing 23 side, and is formed in a quadrangular prism shape on the opposite side. The shaft 18 is inserted into the through-hole 35 of the lower casing 25 so that the axes coincide with each other. A male screw 57 is formed along the outer periphery of the upper end of the shaft 18 on the upper casing 23 side, and a part of the male screw 57 is screwed into the female screw 56 of the rotor yoke 45. That is, the axis of the shaft 18 and the rotation center of the rotor yoke 45 of the motor unit 17 are located on the same axis. In the present embodiment, the male screw 57 constitutes a conversion means and a screw mechanism.

  The lock bar main body 21 is formed in a plate shape and is located in the through hole 35 of the lower casing 25, and its size is slidable in the through hole 35 in the vertical direction. . The lock bar main body 21 is provided with a shaft support portion 58 so as to be cut out in a rectangular parallelepiped shape from the upper end, which is the end portion on the upper casing 23 side, to the middle thereof. Further, the lock bar main body 21 is provided with a substantially cylindrical recess 59 so as to be continuous from the shaft support 58 and recessed toward the lower end. The lower end of the shaft 18 is inserted into the shaft support 58 and the recess 59, and the shaft support 58 and the recess 59 are sized along the axial direction of the shaft 18. Thus, the size can be moved relative to the lock bar main body 21.

The lock bar main body 21 has a pair of left and right elongated holes 21a and 21b. The long holes 21 a and 21 b are provided so as to communicate between the shaft support portion 58 and the outside of the lock bar main body 21 in a direction perpendicular to the axis of the shaft 18. A pin 63 is press-fitted into the shaft 18 in a direction perpendicular to the axis of the shaft 18, and both ends of the pin 63 are respectively inserted into the long holes 21 a and 21 b of the lock bar main body 21. On the other hand, it is slidably inserted. As a result, the lock bar main body 21 is supported so as to be relatively movable with respect to the shaft 18 along the axial direction of the shaft 18.

  A spring 61 is interposed between the lock bar main body 21 and the shaft 18. One end of the spring 61 is fixed in the recess 59 of the lock bar main body 21, and the other end is fixed to the lower end of the shaft 18. The spring 61 absorbs the collision between the lock bar main body 21 and the shaft 18. Further, the lower end of the lock bar main body 21 is exposed to the outside from the lower casing 25, and is provided to face the steering shaft 65. Furthermore, the lower end of the lock bar main body 21 is formed in a shape that can be engaged with an engagement groove (not shown) of the steering shaft 65. As described above, the motor unit 17 is provided at a position facing the steering shaft 65 with the shaft 18 and the lock bar main body 21 interposed therebetween.

  In the electric steering lock device 11 configured as described above, when the coil 43 of the motor unit 17 is energized and the rotor yoke 45 is rotated forward, the rotational motion of the rotor yoke 45 is screwed between the female screw 56 and the male screw 57. Is converted into linear motion of the shaft 18. As a result, the shaft 18 moves in the direction opposite to the upper casing 23, that is, toward the steering shaft 65. Then, the lock bar main body 21 connected to the shaft 18 via the spring 61 and the pin 63 moves to the steering shaft 65 side, and the lower end of the lock bar main body 21 is engaged with the engagement groove of the steering shaft 65. To be in the locked position. Thereby, the steering (not shown) of the vehicle is set in a state where the rotation is restricted, that is, in a locked state.

  If the position of the steering shaft 65 in the rotational direction is deviated, the lock bar main body 21 may come into contact with a portion other than the engagement groove of the steering shaft 65 and the locked state may not be achieved. Even in such a case, the movement of the shaft 18 is continued to a necessary position by the contraction of the spring 61. After that, when the position of the steering shaft 65 in the rotational direction is changed and the lock bar main body 21 and the engagement groove of the steering shaft 65 are brought into a state of facing each other, the lock bar main body 21 is engaged by the urging force of the spring 61. Move to position and lock.

  Next, when the coil 43 of the motor unit 17 is energized so as to reversely rotate the rotor yoke 45, the rotor yoke 45 rotates reversely, and the shaft 18 is opposite to the direction of the upper casing 23, that is, the steering shaft 65. Move in the direction of. Then, the lock bar main body 21 connected to the shaft 18 via the pin 63 is separated from the steering shaft 65, and the engagement between the lock bar main body 21 and the engagement groove of the steering shaft 65 is released. As a result, the lock bar main body 21 is in the unlocked position, and the vehicle steering is released from the rotation restriction, that is, the unlocked state.

In the present embodiment, the rotational speed of the rotor yoke 45 is detected by the Hall element 55, and when the detected rotational speed reaches a predetermined rotational speed, the energization to the coil 43 is stopped. It is possible to perform control. Thereby, it can restrict | limit so that the lock bar main body 21 may not move more than necessary. That is, in the present embodiment, motor control is performed based on the detection result from the Hall element 55 by a control device or the like provided on the substrate 16, and the position of the lock bar main body 21 from the rotational speed of the rotor yoke 45, that is, The stroke is converted, and the lock and unlock positions of the lock bar main body 21 are detected based on the conversion result, and the rotation of the motor unit 17 is controlled.

Therefore, according to the present embodiment, the following effects can be obtained.
The outer rotor type motor unit 17 is employed as an electric motor for generating a driving force for moving the lock bar main body 21 of the electric steering lock device 11 between the lock position and the unlock position. Accordingly, the torque generated by the rotor yoke 45 as a rotor is larger than when an inner rotor type is adopted, and the electric motor itself can be reduced in size without reducing the motor output. Therefore, it is not necessary to enlarge the motor unit 17 or to rotate it at high speed in order to compensate for the decrease in motor output. As a result, it is not necessary to provide a speed reduction mechanism between the motor unit 17 and the lock bar main body 21, and it becomes easy to reduce the size of the entire apparatus and to prevent an increase in operating time. Furthermore, since it does not rotate at high speed, the operating noise can be reduced.

  -The motor unit 17 is a brushless motor. Therefore, a mechanical rectification mechanism such as a DC motor is not required, and the electric steering lock device 11 can be a simple structure and easy maintenance.

  The motor unit 17 is a brushless motor, and the motor control hall element 55 normally provided in the brushless motor can be used to determine the position of the lock bar body 21, that is, the stroke. . That is, the number of rotations of the rotor yoke 45 is detected via the Hall element 55 by the control device of the substrate 16 and the position of the lock bar main body 21, that is, the stroke is converted from the detection result. Therefore, when the motor unit 17 is a DC motor, a dedicated switch or hall element for detecting the movement of the shaft 18 or the lock bar main body 21 is necessary to operate the lock bar main body 21 between the necessary strokes. However, according to the present embodiment, such a need is not necessary. That is, it is possible to detect the stroke of the lock bar main body 21 by replacing the Hall element without providing a new part. The Hall element can be detected by motor control and lock / lock position detection of the lock bar main body 21. Can be used for both. As a result, it is possible to prevent the motor unit 17 from being continuously driven in a state where the lock bar main body 21 is in the locked position or the unlocked position, and it is possible to prevent the motor unit 17 from being overloaded.

  The rotational motion of the rotor yoke 45 is converted into the linear motion of the lock bar main body 21 by a screw mechanism constituted by the female screw 56 and the male screw 57. In other words, the space can be converted with a simple structure as compared with the case where a cam, a crank, or the like is employed.

  The female screw 56 and the male screw 57 constituting the screw mechanism are provided on the rotor yoke 45 and the shaft 18. Therefore, the screw mechanism can be easily provided only by performing a process of cutting the existing rotor yoke 45 or the shaft 18 without any special new parts.

  The rotor yoke 45 includes a large-diameter portion 45a and a small-diameter portion 45b, and the screw mechanism includes a female screw 56 provided on the inner peripheral surface of the small-diameter portion 45b of the rotor yoke 45 and a male screw 57 provided on the shaft 18. It was made to be. Therefore, the screw mechanism can be provided with a simple structure as compared with the case where the male screw is provided on the rotor yoke 45 side and the female screw is provided on the shaft 18 side.

The axial center of the shaft 18 and the rotation center of the rotor yoke 45 of the motor unit 17 are coaxially positioned. Therefore, the overall size of the electric steering lock device 11 can be made compact, and the rotational movement of the rotor yoke 45 can be efficiently transmitted to the shaft 18 and the lock bar main body 21.

  The motor unit 17 is provided at a position facing the steering shaft 65 with the shaft 18 and the lock bar main body 21 interposed therebetween. Therefore, compared with the case where the motor unit 17 is provided around the intermediate portion of the shaft 18 and the lock bar main body 21, the arrangement of the substrate 16 is taken into consideration, and the overall size of the electric steering lock device 11 is compact. It can be made.

In addition, you may change the said embodiment into the following aspects.
In the above embodiment, the motor unit 17 is a brushless motor. If this is an outer rotor type motor with a relatively large generated torque, it may be a motor other than a brushless motor, for example, an AC motor or a DC motor employing a mechanical rectifying mechanism.

  In the above embodiment, the screw mechanism is employed as the conversion means for converting the rotational motion of the motor unit 17 into the linear motion of the lock bar main body 21. Alternatively, other conversion means such as a cam or a crank may be employed.

  In the above embodiment, the screw mechanism is provided on the rotor yoke 45 and the shaft 18. As long as the rotational motion of the rotor yoke 45 can be converted into the linear motion of the lock bar main body 21, this may be provided in other components. For example, a part having a female thread and a part having a male thread may be newly provided between the rotor yoke 45 and the shaft 18.

  In the above embodiment, the screw mechanism is configured by the internal thread 56 provided on the inner peripheral surface of the small diameter portion 45 b of the rotor yoke 45 and the external thread 57 provided on the shaft 18. Alternatively, the rotor yoke 45 may be provided with a male screw and the shaft 18 may be provided with a female screw. In such a case, the shape of the rotor yoke 45 may be a shape in which a male screw can be easily provided. Further, the shape of the shaft 18 may be a shape in which a female screw can be easily provided.

  In the above embodiment, the lock bar includes the shaft 18 and the lock bar main body 21. This may be configured only by the lock bar main body 21. In this case, the lock bar main body 21 may be provided with a male screw 57 to transmit the rotational movement of the rotor yoke 45 directly to the lock bar main body 21.

Next, the technical idea that can be grasped from the above embodiment and the change of the aspect will be additionally described below.
(A) In the electric steering lock device according to any one of claims 1 to 6, an axis of the lock bar and a rotation center of the electric motor are located on the same axis. Electric steering lock device.

  (B) In the electric steering lock device according to any one of claims 1 to 6 and (A), the electric motor is provided at a position facing the steering shaft across the lock bar. An electric steering lock device.

Sectional drawing of the electric steering lock apparatus in this embodiment. Similarly, the top view of an electric steering lock device. The perspective view of the conventional electric steering lock device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Electric steering lock apparatus, 17 ... Motor part as an electric motor, 18 ... Shaft which comprises a lock bar, 41 ... Stator core, 43 ... Coil, 45 ... Rotor yoke, 45a ... Large diameter part, 45b ... Small diameter part, 51 53... Ball bearing as a bearing, 54... Magnet, 55. Hall element, 56... Female screw constituting the conversion means and screw mechanism, 57... Male screw constituting the conversion means and screw mechanism, 65.

Claims (6)

A lock bar that is movable to a lock position that restricts rotation of the steering shaft and an unlock position that releases the restriction of rotation of the steering shaft, and the lock bar is moved between the lock position and the unlock position. In an electric steering lock device including an electric motor that generates a driving force for causing
The electric steering lock device, wherein the electric motor is an outer rotor type.   2. The electric steering lock device according to claim 1, wherein the electric motor is a brushless motor.   3. The electric steering lock device according to claim 2, further comprising conversion means for converting the rotational movement of the electric motor into a linear movement in the movement direction of the lock bar, the conversion means being a screw mechanism. Electric steering lock device. In the electric steering lock device according to claim 3,
The brushless motor is
A stator core wound with a coil;
A rotor yoke supported rotatably with respect to the stator core via a bearing provided on an inner peripheral surface of the stator core;
A magnet fixed to the rotor yoke so as to face the coil,
The electric steering lock device, wherein the screw mechanism is provided on the rotor yoke and the lock bar. In the electric steering lock device according to claim 4,
The rotor yoke is
A cylindrical large-diameter portion that supports the magnet;
A diameter smaller than the large diameter portion, and a cylindrical small diameter portion fixed to the inside of the bearing,
The screw mechanism is
A female screw provided on the inner peripheral surface of the small diameter portion of the rotor yoke;
An electric steering lock device comprising a male screw provided on the lock bar. In the electric steering lock device according to any one of claims 2 to 5,
The brushless motor is
A hall element that detects the rotation speed of the brushless motor;
An electric steering lock device comprising: conversion means for converting the position of the lock bar based on the number of revolutions detected by the Hall element.

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