JP2014031029A - Electric steering lock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent erroneous determination of an unlocked state when a magnetic detection sensor fails on the sensitive side.
In an electric steering lock device, a lock member movable between a lock position for suppressing rotation of a steering shaft and an unlock position for allowing rotation of the steering shaft, and a first magnet provided on the lock member A magnetic detection sensor provided at a position facing the first magnet when the lock member is in the unlock position, and a second magnet provided at the lock member, wherein the lock member is at the lock position and the unlock position. When the lock member is positioned between the lock position and the unlock position without facing the magnetic detection sensor, a second magnet is provided that faces the magnetic detection sensor.
[Selection] Figure 5

Description

  The present invention relates to an electric steering lock device.

  Conventionally, in order to prevent erroneous detection at the unlock position of the lock member, a lock member that is movable between a lock position that engages with the steering shaft of the vehicle and an unlock position where the engagement is released, and a lock An electric steering lock device is known that includes a first magnetic detection sensor that switches from an on state to an off state when a member moves to an unlocked position, and a second magnetic detection sensor that switches from an off state to an on state. (For example, refer to Patent Document 1). According to the configuration described in Patent Document 1 described above, when a strong electromagnetic field is generated such that both the first and second magnetic detection sensors are turned on, the first magnetic detection sensor is not turned off. This can prevent erroneous detection at the unlock position of the lock member.

JP 2012-025269

  However, in the configuration described in Patent Document 1, two magnetic detection sensors are required to prevent erroneous determination (false detection) of the unlocked state. In addition, when the second magnetic detection sensor reacts to a minute magnetic force due to a failure (the magnetic detection sensor has failed on the sensitive side), the second magnetic detection sensor is changed to the unlocked state before the change. There is also a problem in that erroneous determination may occur due to switching from the off state to the on state.

  Accordingly, an object of the present invention is to provide an electric steering lock device capable of preventing erroneous determination of an unlocked state when a magnetic detection sensor fails on the sensitive side.

In order to achieve the above object, according to one aspect of the present invention, in an electric steering lock device,
A lock member movable between a lock position for suppressing rotation of the steering shaft and an unlock position for allowing rotation of the steering shaft;
A first magnet provided on the lock member;
A magnetic detection sensor provided at a position facing the first magnet when the lock member is in the unlock position;
A second magnet provided in the lock member, wherein the lock member does not face the magnetic detection sensor when the lock member is in the lock position and the unlock position, and the lock member is in the lock position and the unlock position. And a second magnet facing the magnetic detection sensor when positioned between the first and second magnets, an electric steering lock device is provided.

  According to the present invention, it is possible to obtain an electric steering lock device that can prevent erroneous determination of an unlocked state when a magnetic detection sensor fails on the sensitive side.

It is a figure (locking state) which shows the principal part cross section of the electric steering lock apparatus 1 by one Example. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure (unlocked state) which shows the principal part cross section of the electric steering lock apparatus 1 by one Example. 3 is a diagram illustrating an example of a relationship between a motor 10 and a shaft portion 15. FIG. FIG. 3 is a diagram illustrating an example of an arrangement mode of Hall elements 31 and 32 on a substrate 28. It is explanatory drawing of the preferable Example of the arrangement | positioning aspect of the 1st magnet 27a and the 2nd magnet 27b. It is a figure which shows an example of the output pattern of the Hall element 32 when the lock bar 11 moves toward a unlock position from a lock position. 3 is a flowchart showing an example of main processing executed by a steering lock ECU 30.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIGS. 1 and 2 are cross-sectional views showing an essential part of an electric steering lock device 1 according to an embodiment. FIG. 1 shows a locked state, and FIG. 2 shows an unlocked state. FIG. 3 is a diagram illustrating an example of the relationship between the motor 10 and the shaft portion 15. FIG. 4 is a diagram illustrating an example of an arrangement mode of the Hall elements 31 and 32 on the substrate 28.

  The electric steering lock device 1 is a device that uses a motor 10 to lock / unlock the steering device. Specifically, the electric steering lock device 1 moves the lock bar 11 by the driving force of the motor 10 between a lock position that suppresses rotation of the steering shaft 2 and an unlock position that allows rotation of the steering shaft 2. By moving, the locked state (FIG. 1) and unlocked state (FIG. 2) of the steering device are selectively realized. The electric steering lock device 1 may be mounted on, for example, a column tube 5 (the whole is not shown).

  The motor 10 may be a DC motor, for example. As shown in FIG. 3, a substantially cylindrical shaft portion 15 is connected to the rotating shaft 10 a of the motor 10 via a worm gear 14. The shaft portion 15 is connected in a direction orthogonal to the rotation shaft 10a in a rotatable state. Specifically, a worm 14a is attached to the distal end of the rotating shaft 10a of the motor 10, and a bulging portion 15a is provided at the proximal end of the shaft portion 15, and a worm wheel (helical gear) is provided on the bulging portion 15a. ) 14b is attached, and the motor 10 and the shaft portion 15 are connected by meshing these gears. The worm gear 14 decelerates the rotation of the motor 10 and transmits it to the shaft portion 15.

  As shown in FIGS. 1 and 2, a lock stopper 16 that supports the lock bar 11 is attached to the shaft portion 15 so as to be movable along the axial direction of the shaft portion 15. The lock stopper 16 may be made of a non-metallic component such as zinc die casting. The lock stopper 16 is slidably supported by the case body 7 (the whole is not shown) and is non-rotatable. The lock stopper 16 has a through hole 19 through which the shaft portion 15 passes. As shown in FIG. 3, a male screw portion 20 is integrally formed on the outer peripheral surface of the large-diameter portion 15 b at the intermediate position of the shaft portion 15. A female screw portion 21 that is screwed with the male screw portion 20 of the shaft portion 15 is formed on the entire inner peripheral surface of the through hole 19.

  The lock bar 11 is made of a metal made of, for example, iron or aluminum, and has a quadrangular columnar locking protrusion 11a that fits into the recess 12a of the steering shaft 2, and the locking protrusion 11a. And a locking frame 11b having a square frame shape for supporting the frame at the base end side. The lock bar 11 is assembled to the lock stopper 16 by being engaged with an engagement recess 16 c provided in the back surface of the lock stopper 16. In the locked state, the lock bar 11 protrudes toward the steering shaft 2 through the holes 22 and 23 as shown in FIG.

  An urging spring 24 made of, for example, a metal coil spring is interposed between the lock stopper 16 and the lock bar 11. The urging spring 24 urges the lock bar 11 toward the steering shaft 2, thereby preventing the lock bar 11 from riding on the convex portions 12 b between the concave portions 12 a of the steering shaft 2, thereby ensuring the recess 12 a. Works to lock on. One end of the biasing spring 24 is accommodated in the accommodation hole 25 formed in the lock stopper 16, and the other end abuts on the step surface 11 c of the lock bar 11. The lock bar 11 is urged toward the steering shaft 2 by the urging spring 24, but further sliding movement is restricted by the locking frame 11 b coming into contact with the back surface of the lock stopper 16. .

  The lock stopper 16 is provided with a first magnet 27 a and a second magnet 27 b that are used when detecting the position of the lock bar 11. As shown in FIGS. 1 and 2, the first magnet 27 a and the second magnet 27 b are provided so as to be exposed on the side of the lock stopper 16 facing the substrate 28. The first magnet 27a and the second magnet 27b are permanent magnets, and may be composed of, for example, a sintered magnet. The first magnet 27a and the second magnet 27b may be held by the lock stopper 16 in an arbitrary manner. For example, the first magnet 27a and the second magnet 27b may be held in a manner to be attracted to the lock bar 11 by their own magnetic force, or using a holder or the like. May be held. The first magnet 27a and the second magnet 27b may have the same configuration or different configurations. In addition, the first magnet 27a and the second magnet 27b may be spaced apart from each other by the same distance (in the direction perpendicular to the surface of the substrate 28) with respect to the substrate 28, or may be spaced apart from each other by different distances. Also good. In addition, the preferable Example of the arrangement | positioning aspect of the 1st magnet 27a and the 2nd magnet 27b is mentioned later.

  When the motor 10 is operated, the rotation of the motor 10 is transmitted to the shaft portion 15 via the worm gear 14, and the shaft portion 15 rotates. Here, the shaft portion 15 is supported by the case main body 7 so as to be slidable and non-rotatable while the male screw portion 20 of the shaft portion 15 is screwed into the female screw portion 21 of the lock stopper 16. Therefore, when the shaft portion 15 rotates, the rotational motion of the shaft portion 15 is converted into a linear motion of the lock stopper 16, and the lock stopper 16 slides along the axial direction of the shaft portion 15. In this way, the lock stopper 16 is slid along the axial direction by the motor 10. At this time, since the lock bar 11 is assembled to the lock stopper 16, the lock bar 11 moves linearly together with the lock stopper 16. When the lock bar 11 slides toward the steering shaft 2 and fits into the recess 12a of the steering shaft 2, the locked state is as shown in FIG. On the other hand, when the motor 10 rotates in the reverse direction and the lock bar 11 comes out of the recess 12a as shown in FIG.

  A board 28 on which various electronic components of the electric steering lock device 1 are mounted is provided at a position facing the lock stopper 16. The substrate 28 is housed in the case body 7 in a state where the electronic component mounting surface is covered with an internal case 29 having an open bottom. A guide recess 29a is formed on the upper wall of the inner case 29 along the moving direction of the lock stopper 16 (lock bar 11). The guide recess 29a forms a space for sliding movement of a portion of the lock stopper 16 that holds the first magnet 27a and the second magnet 27b.

  A steering lock ECU 30 that drives and controls the motor 10 is mounted on the substrate 28. A pair of magnetic sensors (for example, Hall elements 31 and 32) for detecting the magnetic field intensity generated by the first magnet 27a is mounted on the substrate 28 at a position facing the first magnet 27a. One of the hall elements 31 and 32 is disposed at a position facing the first magnet 27a when the lock bar 11 reaches the lock position, and a position facing the first magnet 27a when the lock bar 11 is positioned at the unlock position. The other is arranged. The hall elements 31 and 32 output an electrical signal corresponding to the detected magnetic field intensity to the steering lock ECU 30. The steering lock ECU 30 determines the position of the lock bar 11 (for example, the lock position or the unlock position) based on the electrical signals from the hall elements 31 and 32. The Hall elements 31 and 32 may output an on / off signal as an electrical signal corresponding to the detected magnetic field intensity. That is, the Hall elements 31 and 32 may be configured such that the output signal is turned on when the detected magnetic field intensity exceeds a predetermined threshold value.

  The lock position corresponds to the end position on the lock side of the movement stroke of the lock bar 11, and the unlock position corresponds to the end position on the unlock side of the movement stroke of the lock bar 11. Therefore, the lock state can be realized not only when the lock bar 11 is in the lock position but also when it is positioned in front of the lock position. Similarly, the unlocked state can be realized not only when the lock bar 11 is in the unlock position, but also when the lock bar 11 is positioned before the unlock position.

  FIG. 5 is an explanatory view of a preferred embodiment of the arrangement mode of the first magnet 27a and the second magnet 27b, (A) shows the locked state when the lock bar 11 is in the locked position, and (B) is The first state (first movement state) in the middle of moving from the locked state to the unlocked state is shown, and (C) is the second state (first movement state in the middle of moving from the locked state to the unlocked state). (D) shows an unlocked state when the lock bar 11 is in the unlocked position. The first movement state and the second movement state do not belong to either the locked state or the unlocked state. Note that FIG. 5 shows only the components that are mainly necessary for explaining the arrangement of the first magnet 27a and the second magnet 27b in a very schematic manner. For example, since the lock bar 11 basically moves together with the lock stopper 16, the lock bar 11 is illustrated as an integral member with the lock stopper 16.

  As described above, as shown in FIG. 5D, the first magnet 27a is located at a position facing the hall element 32 (the hall element 32 for detecting the unlocked state) when the lock bar 11 is at the unlock position. Provided. As shown in FIG. 5A, the first magnet 27a at this position opposes the hall element 31 (the hall element 31 for detecting the lock state) when the lock bar 11 is at the lock position.

  As shown in FIG. 5, the second magnet 27b does not oppose the hall element 32 (the hall element 32 for detecting the unlocked state) when the lock bar 11 is in the locked position or in the unlocked position. When the bar 11 is positioned between the lock position and the unlock position, the bar 11 is provided at a position facing the hall element 32.

  More specifically, in each state, in the locked state when the lock bar 11 is in the locked position, both the first magnet 27a and the second magnet 27b are in positions that do not face the hall element 32, and accordingly The output of the Hall element 32 is turned off when the Hall element 32 is in a normal state (that is, when it does not fail on the sensitive side described below). In the locked state when the lock bar 11 is in the locked position, the first magnet 27a is in a position facing the hall element 31 (the hall element 31 for detecting the locked state), and therefore the output of the hall element 31 is Is on (this allows the lock state to be detected).

  In the first movement state, the lock bar 11 is moved from the lock position toward the unlock position by a predetermined amount L1, and accordingly, the second magnet 27b is at a position facing the hall element 32. Accordingly, the output of the Hall element 32 is turned on in response to the magnetic field from the second magnet 27b. In this first movement state, the first magnet 27a moves from a position facing the hall element 31, so that the output of the hall element 31 is turned off.

  In the second movement state, the lock bar 11 is moved from the lock position toward the unlock position by a predetermined amount L2 (> L1), and accordingly, the second magnet 27b passes the position facing the hall element 32. Thus, it does not face the Hall element 32. Further, the first magnet 27 a has not yet reached the position facing the hall element 32 and does not face the hall element 32. Therefore, in the second movement state, the output of the Hall element 32 is the first magnet 27a and the second magnet 27b when the Hall element 32 is in a normal state (that is, when there is no failure on the sensitive side described below). It turns off without reacting to the magnetic field from both.

  In the unlocked state when the lock bar 11 is in the unlock position, the lock bar 11 is moved by a predetermined amount L3 (> L2) from the lock position to the unlock position, and accordingly, the second magnet 27b is Further away from the position facing the hall element 32, it remains unopposed to the hall element 32. On the other hand, the first magnet 27a reaches a position facing the hall element 32 (coming to a position facing the hall element 32). Therefore, in the unlocked state when the lock bar 11 is in the unlocked position, the output of the Hall element 32 is turned on in response to the magnetic field from the first magnet 27a.

  FIG. 6 shows the amount of movement of the lock bar 11 when the lock bar 11 moves from the locked position toward the unlocked position in the configuration shown in FIG. It is a figure which shows an example of the relationship of / off). Here, it is assumed that the Hall element 32 is in a normal state (that is, a case where the Hall element 32 has not failed on the sensitive side described below).

  When the lock bar 11 moves from the locked position toward the unlocked position, the output of the Hall element 32 changes from the off state to on, off, and on as shown in FIG. In the example shown in FIG. 6, the predetermined amount L1 corresponds to a boundary position where the output of the Hall element 32 is turned from OFF to ON, but the section in the ON state after the output of the Hall element 32 is turned from OFF to ON. May correspond to the center position of. The same applies to L2, and the predetermined amount L2 corresponds to the boundary position where the output of the Hall element 32 turns from on to off, but may correspond to the center position of the section in which the output is turned off. In the example shown in FIG. 6, L3 ′ corresponds to the boundary position where the output of the Hall element 32 is turned from OFF to ON, but the unlock position (predetermined amount L3) exists on the far side from this boundary position. (In other words, the boundary position corresponding to L3 ′ may be positioned before the unlock position corresponding to L3). Since these may differ from product to product depending on the sensitivity and assembly accuracy of the Hall element 32, they do not have a strict meaning. In short, the on / off timing is irrelevant, and when the output of the Hall element 32 that can be regarded as a normal state moves from the locked position toward the unlocked position, the output from the off state turns on, off, and on. And change.

  In the example shown in FIG. 5, as shown in FIGS. 5A and 5C, the position of the first magnet 27a with respect to the Hall element 32 in the second movement state is that the lock bar 11 is in the locked position. Coincides with the position of the second magnet 27b with respect to the Hall element 32 at the time. That is, the first magnet 27a and the second magnet 27b are separated from each other by a predetermined amount L2 on the lock bar 11. In such a configuration, in the second movement state, as shown in FIG. 5C, the first magnet 27 a is separated from the hall element 32 by ΔD 1, and the second magnet 27 b is separated from the hall element 32 by ΔD 2. Only separated. In this case, ΔD1 and ΔD2 are arbitrary as long as the normal Hall element 32 is not turned on due to the magnetic fields from the first magnet 27a and the second magnet 27b. Note that ΔD1 may be substantially the same as ΔD2 (that is, ΔD1≈ΔD2≈L2 / 2).

  FIG. 7 is a flowchart showing an example of main processing executed by the steering lock ECU 30. Note that the processing shown in FIG. 7 may be realized by other control device (s) other than the steering lock ECU 30 or may be realized by cooperation of the steering lock ECU 30 and other control devices. . The process shown in FIG. 7 is started when the engine start switch is operated in the ignition off state (for example, when the start switch is pressed while the brake pedal is depressed while the shift lever is in the parking position). It's okay.

  In step 700, it is determined whether or not the Hall element 32 (Hall element 32 for detecting the unlocked state) is in an OFF state. Since the lock bar 11 is in the locked position in the parking state, the output of the hall element 32 is turned off when the hall element 32 is normal. If the Hall element 32 is in the OFF state, the process proceeds to Step 702. If the Hall element 32 is in the ON state, it is determined that the Hall element 32 has failed on the sensitive side, and the process proceeds to Step 708.

  In step 702, the motor 10 is driven so that the lock bar 11 moves from the lock position toward the unlock position.

  In step 704, the output pattern of the hall element 32 during the driving of the motor 10 in step 702 (that is, the movement of the lock bar 11) is acquired. As described above, when the Hall element 32 is normal, the acquired output pattern is a pattern that changes from the off state to on, off, and on.

  In step 706, it is determined whether or not the output pattern acquired in step 704 is a pattern that changes from an off state to on, off, and on. If the output pattern acquired in step 704 is a pattern that changes from off to on, off, and on, it is determined that the unlocked state (unlocking operation completed) has been detected by the normal hall element 32. The process proceeds to step 710. On the other hand, when the output pattern is not a pattern that changes from the off state to on, off, and on (for example, a pattern in which the on state is maintained after being turned on from the off state), it is determined that the Hall element 32 has failed. Then, the process proceeds to Step 708.

  In step 708, processing for suppressing engine start is executed. For example, a drive prohibition signal for a starter motor (not shown) may be transmitted to a control device that drives and controls the starter motor. In addition to prohibiting the starter motor from being driven, an alarm (such as a message) indicating that the steering apparatus cannot be unlocked may be output. In this case, the user can understand why the engine cannot be started. Note that when the processing itself shown in FIG. 7 is executed by a control device that drives and controls the starter motor, it is only necessary that the control device does not drive the starter motor.

  In step 710, processing for permitting engine start is executed. For example, a drive permission signal for a starter motor (not shown) may be transmitted to a control device that drives and controls the starter motor. When the process itself shown in FIG. 7 is executed by a control device that drives and controls the starter motor, the control device may start the process of driving the starter motor.

  Thus, according to the process shown in FIG. 7, when the output pattern of the hall element 32 changes from the off state to on, off, and on, it is determined that the hall element 32 is normal and the engine is started. Allow. On the other hand, if the output pattern of the Hall element 32 is not a pattern that changes from OFF to ON, OFF, or ON, it is determined that the Hall element 32 has failed and engine start is suppressed.

  The process shown in FIG. 7 permits the engine to start on the condition that the output pattern of the hall element 32 changes from the off state to on, off, and on, but other conditions (for example, hall The output of the element 31 is off) may be added.

  In the process shown in FIG. 7, it is confirmed in step 700 that the initial output state of the Hall element 32 is OFF. However, the process in step 700 is omitted, and instead in step 706. The determination may be made in consideration of the initial output state of the Hall element 32. That is, the determination process in step 706 may substantially include the determination process in step 700.

  By the way, if the Hall element 32 fails on the sensitive side, the Hall element 32 may be turned on in response to a slight magnetic field (a magnetic field strength that is significantly smaller than the magnetic field strength that is intended to be turned on). . For example, the Hall element 32 may be turned on in response to the magnetic field from the first magnet 27a in the first movement state or the second movement state shown in FIG. In this case, in a comparative configuration that does not include the second magnet 27b (that is, a comparative configuration that determines that the Hall element 32 is in the unlocked state when the Hall element 32 is turned on), the first movement state and the second movement shown in FIG. In the state, there is a risk of determining that the state is unlocked (ie, erroneous detection of the unlocked state may occur).

  On the other hand, in this embodiment, in addition to the first magnet 27a, the second magnet 27b is set, and the second magnet 27b is appropriately arranged to prevent such erroneous detection. Specifically, when the Hall element 32 fails on the sensitive side, the Hall element 32 can be turned on in response to the magnetic field from the second magnet 27b in the locked state. Further, the Hall element 32 can be turned on in response to the magnetic field from the first magnet 27a and / or the second magnet 27b in the second movement state. Therefore, if the Hall element 32 fails on the sensitive side, the output of the Hall element 32 does not change from the OFF state to ON, OFF, or ON when the lock bar 11 moves from the locked position toward the unlocked position. That is, the output of the Hall element 32 is maintained in an on state (that is, always on), changed from an on state to off, on, and the like. Therefore, the unlocked state can be accurately determined by determining that the Hall element 32 has shifted to the unlocked state only when the output of the Hall element 32 changes from the off state to on, off, and on. Thus, according to the present embodiment, it is possible to prevent an erroneous determination of the unlocked state due to a failure on the sensitive side of the Hall element 32, and to detect the unlocked state with high accuracy.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the present invention. Can be added.

  For example, the configuration of the lock mechanism of the electric steering lock device 1 has been described with reference to FIGS. 1 and 2, but the detailed configuration of the lock mechanism is not limited to the illustrated configuration and is arbitrary. For example, in the configuration described above, the lock bar 11 directly acts on the steering shaft 2, but the lock bar 11 may act on another member that rotates integrally with the steering shaft 2. In the configuration described above, the first magnet 27 a and the second magnet 27 b are provided on the lock stopper 16 that moves together with the lock bar 11, but the first magnet 27 a and the second magnet 27 b are used for the movement of the lock bar 11. It may be provided on any lock member (including the lock bar 11 itself) that moves with it. The first magnet 27a and the second magnet 27b may be attached to different members.

  In the embodiment described above, the Hall element 32 is used as the magnetic detection sensor. However, the type of the magnetic detection sensor is arbitrary, for example, a search coil (magnetic pickup coil), a magnetoresistive element (MR sensor), or the like. May be used.

DESCRIPTION OF SYMBOLS 1 Electric steering lock apparatus 2 Steering shaft 7 Case main body 10 Motor 10a Rotating shaft 11 Lock bar 11a Locking protrusion 11b Locking frame 11c Step surface 12a Recessed part 12b Protruding part 14 Worm gear 14b Warm wheel 15 Shaft part 15a Swelling part 15b Large diameter Part 16 Lock stopper 16c Locking concave part 19 Through hole 20 Male thread part 21 Female thread part 22, 23 hole 24 Energizing spring 25 Storage hole 27a First magnet 27b Second magnet 28 Substrate 29 Inner case 29a Guide recess 30 Steering lock ECU
31, 32 Hall element

Claims (4)

In the electric steering lock device,
A lock member movable between a lock position for suppressing rotation of the steering shaft and an unlock position for allowing rotation of the steering shaft;
A first magnet provided on the lock member;
A magnetic detection sensor provided at a position facing the first magnet when the lock member is in the unlock position;
A second magnet provided in the lock member, wherein the lock member does not face the magnetic detection sensor when the lock member is in the lock position and the unlock position, and the lock member is in the lock position and the unlock position. And a second magnet that faces the magnetic detection sensor when positioned between the electric steering lock device and the electric steering lock device.   When the locking member moves from the locked position to the unlocked position, the first magnet and the second magnet change the output signal of the magnetic detection sensor in a normal state from on to off, on, off, and on. The electric steering lock device according to claim 1. A control device connected to the magnetic detection sensor;
The electric steering lock device according to claim 1 or 2, wherein the control device executes or permits engine start when an output signal of the magnetic detection sensor changes from an off state to on, off, and on.   The electric steering lock device according to claim 3, wherein the control device suppresses engine start when an output signal of the magnetic detection sensor does not change from an off state to an on, off, or on pattern.

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