Steering lock apparatus

A steering lock apparatus is composed of: a rotational member having an engagement member; an operating portion positioned on a front side of and connected to the rotational member; a holder for holding the rotational member rotatably in forward and backward directions, and for holding the same rotatably in a rear position; an actuator driven by a signal transmitted by a controller upon detection of the rotational member being operated toward a rear side; and a lock member that is operated by the actuator to be engaged with the engagement member of the rotational member in LOCK position for preventing rotation of the rotational member. The rotational member is held rotatably in a rear position and disabled from moving to a front position when the rotational member is operated to a rear position to release engagement between the engagement member of the rotational member and the lock member.

BACKGROUND OF THE INVENTION

The present invention relates to a steering lock apparatus for use in vehicles and the like.

Conventionally, a cylinder lock that allows locking and unlocking without a key has been disclosed in e.g., Japanese Utility Model Kokoku Publication No. 61-28851. This cylinder lock has a rotor equipped with plate-shaped tumblers, and a rotational cylinder with tumbler engagement grooves formed on an inner circumferential face is provided on an outer circumference of the rotor. In the rotational cylinder, there is provided a hole for fitting a top end portion of a plunger driven by an electromagnetic solenoid. When the electromagnetic solenoid is off, the plunger is fit into the hole to prevent rotation of the rotational cylinder, whereas when the electromagnetic solenoid is on, the plunger leaves the hole to bring the rotational cylinder into a rotatable state. For unlocking the cylinder lock with use of a key, the key is inserted into the rotor so that the tumblers sink into the rotor, which releases engagement between the tumblers and the grooves of the rotational cylinder, and thereby enables the rotor to rotate in precisely the same way as general cylinder locks. For unlocking the cylinder lock without use of a key, the electromagnetic solenoid is operated to pull the plunger out of the hole of the rotational cylinder so as to make the rotational cylinder rotatable. In this state, holding and rotating a knob provided on a front face of the rotor implements cooperative rotation of the rotor and the rotational cylinder since the tumblers of the rotor are in engagement with the tumbler engagement grooves of the rotational cylinder.

Generally in steering lock apparatuses, when a key is inserted and a cylinder is rotated from LOCK position to ACC position with use of the key, a steering shaft is unlocked, and this unlocking state is maintained in ON position, Start position, ACC position, and LOCK position after once unlocking the steering shaft. Then, the steering shaft is locked when the key is extracted from the key cylinder in LOCK position. However, in the known steering lock apparatus, since key extraction cannot be detected, operating the key or the knob to the LOCK position after unlocking the steering shaft causes a lock shaft spring out, and thereby locks the steering shaft.

SUMMARY OF THE INVENTION

Accordingly, in view of this point, it is an object of the present invention to provide a steering lock apparatus capable of maintaining an unlocking state once an unlocking operation is conducted, as well as preventing an erroneous locking operation during driving and the like.

In order to achieve the above object, a steering lock apparatus of the present invention is composed of: a rotational member having an engagement member; an operating portion positioned on a front side of the rotational member for rear movement and rotational operation of the rotational member; a holder for holding the rotational member movably in forward and backward directions and for holding the same rotatably in a rear position; an actuator driven by a signal transmitted by a controller upon detection of the rotational member being operated toward a rear side; and a lock member that is operated by the actuator so as to be engaged with the engagement member of the rotational member in LOCK position for preventing rotation of the rotational member, with the rotational member being held rotatably in a rear position and disabled from moving to a front position when the rotational member is operated to a rear position to release engagement between the engagement member of the rotational member and the lock member.

Also, in the steering lock apparatus of the present invention, the engagement member of the rotational member may include a slide groove provided in an axial direction on a lateral wall of the rotational member, and a slide member movably provided in the slide groove and pressed to a rear side by a spring. The slide member may have a first engagement portion that engages with the lock member to prevent rotation of the rotational member and movement of the slide member toward a rear side, and a second engagement portion that engages with the lock member to prevent movement of the slide member toward a front side together with the rotational member, with the sliding member being pressed by the spring when the first engagement portion of the slide member engages with the lock member and the rotational member is operated toward a rear side, then the slide member being moved toward the rear side inside the slide groove by a pressing force of the spring after releasing engagement between the slide member and the lock member, and the lock member being operated to be in a lock state again at a time during which the lock member engages with the second engagement portion of the slide member to prevent movement of the rotational member toward a front side.

Further, the steering lock apparatus of the present invention may be provided with a pressing member for pressing the rotational member toward a front side, with the pressing member moving the rotational member to a front position when engagement of the second engagement portion of the slide member with the lock member is released.

According to the steering lock apparatus of the present invention, once the rotational member is pressed toward the rear side so as to unlock the lock thereof, the rotational member is disabled from moving toward the front side, which prevents mis-operation of the rotational member toward the front side during driving and the like, and eliminates danger of the steering lock being locked.

Also, in locking and unlocking rotation of the rotational member, the actuator needs to be operated only for a short period of time, which achieves steering lock operation with small power consumption.

Further, a driver does not need to operate an operating portion toward the front side when getting out of an automobile since the operating portion is automatically returned to an initial state, which makes it possible to prevent the steering shaft from being left in an unlocked state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1is a cross sectional view showing a steering lock apparatus of the present invention before operation, andFIG. 2is a cross sectional view displaced by 90′ from the cross sectional view of FIG.1. It is noted that the right side is referred to as “front” and the left side is referred to as “rear” in a longitudinal direction of the cross sectional views showing the steering lock apparatus for the sake of convenience.

The steering lock apparatus mainly has a key cylinder1with an operating knob21secured on a front face thereof, a rotational member2for holding the key cylinder1in a rotatable manner, an engagement member3that comes into engagement with a later-described lock member11, and a holder4for holding the rotational member2movably in forward and backward directions, i.e., left and right direction in these drawings, and for holding the same rotatably in a rear position that is the left side in the drawings.

The key cylinder1is connected to a cam member5via a connection protruding portion1a, so that rotating the key cylinder1cooperatively rotates the cam member5, which rotates a rotor (not shown) of a switch portion6provided on a rear end side of the cam member5, resulting in execution of a specified switch operation. Rotation of the cam member5operates a lock shaft7, by which an unshown steering shaft is locked. Each of the above-mentioned members is housed in a body8. On the body8, there is fixed an electromagnetic solenoid9that is an actuator. In a through-hole8aformed in the body8, there is movably disposed the lock member11connected to a top end portion of a driving shaft10of the electromagnetic solenoid9. The lock member11engages with the engagement member3of the rotational member2to restrain a rotating operation of the rotational member2. Between an engagement brim portion5eof the cam member5and the body8at a surrounding portion of the rear end side of the cam member5, there is disposed a spring13, which presses the cam member5, the key cylinder1, and the rotational member2to the front side, that is, the right side in the drawings.

On a front-side outer circumferential face of the body8, there is fixed a key detection switch14for detecting insertion of a key into the key cylinder1. The key detection switch14is equipped with an actuating lever15, which conducts a current to the key detection switch14when pressed. The actuating lever15is inserted into a switch introduction hole60formed in the body8and a through-hole61formed in the holder4in a state of being pressed outside by an unshown spring disposed in the key detection switch14.

The key cylinder1has a columnar shape, and a rectangular key insertion hole17is formed in a central portion thereof as shown in FIG.1and FIG.14. On an outer circumferential face of the key cylinder1, a plurality of tumbler holes18connected to the key insertion hole17is provided on both sides at specified intervals in an axial direction. In each of the tumbler holes18, there is provided a tumbler19pressed by an unshown spring in a radial direction. Similar to known cylinder locks, when a key is inserted into the key insertion hole17, each tumbler19sinks into the key cylinder1.

On a front side of the key cylinder1, there is provided a brim-like portion20protruding annularly, and on a front face of the brim-like portion20, there is secured an operating knob (operating portion)21. Inside the operating knob21, there is provided a key installation hole22through which the key can be introduced into the key insertion hole17.

Also, the key cylinder1is provided with a hole23formed in radial direction and a spring installation hole24connected to the hole23between the brim-like portion20and the tumbler hole18as shown in FIG.13A. In the hole23, a slider25having a rectangular introduction hole26for introducing a key in a central portion thereof is movably provided and pressed in radial direction by a spring27installed in the spring installation hole24as shown in FIG.13A. When a key is not inserted into the key cylinder1, a top end portion25aof the slider25projects from the outer circumferential face of the key cylinder1to prevent rotation of the key cylinder1relative to the rotational member2in cooperation with the tumblers19, as shown in FIG.13A. When a key is inserted into the key cylinder1, the slider25is moved to a position where the top end portion25aand a rear end portion25bof the slider25are aligned with the outer circumferential face of the key cylinder1as shown in FIG.13B.

As shown inFIG. 1, on a rear end portion side of the key cylinder1, C ring30is installed for securing the key cylinder1on the rotational member2. The C ring30is installed on the key cylinder1after the key cylinder1is inserted into the rotational member2from the right side of this drawing, by which the rotational member2is prevented from detaching from the key cylinder1. An outside diameter of the C ring30is almost equal to an outside diameter of the rotational member2. On the rear end portion of the key cylinder1, there is formed a connection protruding portion1aprotruding toward the rear side for connecting the key cylinder1to the cam member5.

The rotational member2has a cylindrical shape, and a pair of tumbler engagement grooves32are formed along an axial direction in symmetrical positions in an inner circumferential face of the rotational member2. A top end portion of each tumbler19engages with a corresponding tumbler engagement groove32to disable the key cylinder1from rotating. There is formed a through-hole33penetrating in radial direction as shown inFIG. 13Ain a position corresponding to the hole23of the key cylinder1on the right side of the tumbler engagement grooves32in FIG.1. In the through-hole33, there is movably provided an engaged member34whose end portion comes into contact with the rear end portion25bof the slider25of the key cylinder1. In a position of the rotational member2opposed to the through-hole33, there is formed a fitting groove35which is connected to the tumbler engagement groove32, and in which the top end portion25aof the slider25of the key cylinder1fits.

The engaged member34moves with the slider25upon insertion of a key into the key cylinder1and presses the actuating lever15of the key detection switch14, by which the key detection switch14is turned on. When a key is not inserted, the engaged member34is positioned so as to cross over the key cylinder1and the rotational member2, and a top end portion34athereof matches with an outer circumferential face of the rotational member2. With a key being inserted as shown inFIG. 13B, the engaged member34moves with the slider25so that the top end portion34athereof projects from the outer circumferential face of the rotational member2, and a contact face between a rear end portion34bof the engaged member34and the rear end portion25bof the slider25aligns with a contact face between the key cylinder1and the rotational member2, which releases connection between the key cylinder1and the rotational member2.

As shown inFIG. 1, on the outer circumferential face of the rotational member2, there are formed a semi-spherical first fitting hole40for fitting part of a ball39that is disposed in the body8and pressed by a ball spring38to a side of the rotational member2when the rotational member2is positioned toward the front side, and a semi-spherical second fitting hole41for fitting part of the ball39when the rotational member2is positioned toward the rear side. The ball39and these two fitting holes40,41generate a clicking feel when the rotational member2is moved from a front position to a rear position or from the rear position to the front position, thereby ensuring movement of the rotational member2to the front position or the rear position.

On the outer circumferential face of the rotational member2, there is provided the engagement member3that engages with the lock member11and disables the rotational member2from rotating. The engagement member3is composed of a slide member51that engages with the lock member11, a slide groove44for disposing the slide member51on the rotational member2movably in an axial direction, and a slide spring49for pressing the slide member51toward a side of the rear end portion of the rotational member2. As shown inFIG. 8, the slide groove44is provided from a rear end portion to an approximately central portion on the outer circumferential face of the rotational member2, and in a lateral wall on a central side provided is a spring installation hole45for installing the spring49in an axial direction. Also, on the outer circumferential face of the rotational member2in a position corresponding to an engagement protruding portion11aof the lock member11when the rotational member2moves toward a rear position, there is formed an operation groove46, one end of which connects to the slide groove44, and another end of which extends in circumferential direction in a range of operation of the rotational member2, i.e., a range of approximately 160 degrees, as shown in FIG.11B.

As shown inFIG. 8, the slide member51is restrained by a lateral wall of the C ring30provided on the rear end portion of the key cylinder1and provided movably in the slide groove44.

The slide member51has a substrate portion52and an approximately L-shaped first engagement portion53protruding from a top face of the substrate portion52. A lateral wall portion of the first engagement portion53constitutes a rotation preventing portion54that engages with the lock member11for preventing clockwise rotation of the rotational member2, and a movement preventing portion55that engages with the lock member11for preventing movement of the slide member51toward the rear side. In an end portion on a side of the slide spring49of the substrate portion52, there is provided a board-shaped protruding portion56that protrudes from the top face of the substrate portion52and comes into contact with the slide spring49. Between the board-shaped protruding portion56and the first engagement portion53, there is formed an engagement groove57that is a second engagement portion, in which the lock member11is fit for preventing the slide member51from moving in forward and backward directions. A bottom face of the engagement groove57is structured to have a height identical to a height of a bottom face of the operation groove46provided in the rotational member2when the slide member51is disposed in the slide groove44.

As shown inFIG. 1, after the holder4, which is for holding the rotational member2rotatably and movably in an axial direction, is assembled to the rotational member2, thus-integrated holder4and rotational member2are inserted into the body8from the right side of this drawing, i.e., the front side, and the holder4is mounted on a front opening portion of the body8. The holder4has an approximately cylindrical shape, and in a specified position on a circumferential wall of the holder4, there is provided a through-hole61for inserting a top end portion of the actuating lever15of the key detection switch14that detects insertion of a key into the key cylinder1.

The switch portion6is for detecting the cam member5being moved toward the rear side. When the switch portion6detects that the key cylinder1and the rotational member2are operated toward the rear side and the cam member5is moved, a controller90is activated to receive an unlocking signal from an unshown electronic key, and if the unlocking signal is a proper signal, the controller90operates the electromagnetic solenoid9for a certain period of time. If the controller90cannot receive the unlocking signal from the electronic key in a certain period of time, the controller90determines that a driver carrying the electronic key is out of an automobile and operates the electromagnetic solenoid9for a certain period of time again.

The electromagnetic solenoid9operates upon reception of a signal from the controller90, and in operation of the electromagnetic solenoid9, a driving axle10is structured to move to a side of the electromagnetic solenoid9. The lock member11is secured on a top end portion of the driving axle10. On the top end portion of the lock member11on a side of the rotational member2, there is protruded the engagement protruding portion11athat engages with the slide member51and the slide groove44for preventing rotation of the rotational member2. Between the lock member11and the electromagnetic solenoid9, a spring62is provided around the driving axle10, and when the electromagnetic solenoid9is not operated, pressing force of the spring62presses the lock member11to the side of the rotational member2, which inserts the engagement protruding portion11aof the lock member11into the slide groove44of the rotational member2.

As shown inFIG. 2, a lock shaft7is movably installed in a hole8bof the body8, and a following portion7athat engages with the cam member5is provided on a rear end portion thereof. On the following portion7a, there is formed a pin installation hole67for installing a pin64and a pin spring65, and the pin64and the pin spring65are housed in the pin installation hole67by a plug66. The pin64is brought into contact with a lateral wall of a later described large diameter potion5bof the cam member5by the pin spring65. Also, the lock shaft7is pressed toward the lock shaft7by a lock spring69disposed between the following portion7aand a lid portion68covering a lower opening portion of the body8.

The cam member5is equipped with a connection portion5afor being connected to the key cylinder1, the large diameter potion5bthat is rotatable in a state of being supported on an inner circumferential face of the body8, a cam portion5cthat engages with the following portion7aof the lock shaft7for pulling the lock shaft7into the body8, an axial portion5dwhose end portion5fis connected to the switch portion6, and the engagement brim portion5ethat protrudes like a brim from the axial portion5dto press the spring13.

Next description discusses operation of the steering lock apparatus having the above-described construction.

First, in a locking state shown in FIG.1andFIG. 2, the electromagnetic solenoid9is in an off state, where the engagement protruding portion11aof the lock member11pressed to the side of the rotational member2by the spring62is inserted between the first engagement portion53of the slide member51and a lateral wall of the slide groove44as shown inFIG. 8, which prevents the rotational member2from rotating, thereby disabling a rotating operation. In this stage, a key is not inserted within the key insertion hole17of the key cylinder1having the operating knob21on its front face, and thus the tumblers19are protruding from the lateral wall of the key cylinder1and are in engagement with the tumbler engagement grooves32of the rotational member2, so that the key cylinder1is also unable to rotate relative to the rotational member2, and therefore rotation of the operating knob21is not possible.

When a driver carrying an electronic key presses the operating knob21toward the rear side, the key cylinder1moves together with the rotational member2and the cam member5inside the body8to a rear position to be in the state of FIG.3. Upon detection of this movement of the cam member5, the switch portion6transmits a signal to the controller90, which receives an unlocking signal transmitted from the electronic key and determines if the signal is proper or not. Here, as shown inFIG. 9, the movement preventing portion55of the first engagement portion53of the slide member51comes into contact with the engagement protruding portion11aof the lock member11, so that the slide member51is unable to move toward the rear side, and therefore the slide member51is in a state of being pressed toward the rear side by the slide spring49.

Further as shown inFIG. 5, with movement of the cam member5, the pin64of the lock shaft7is pressed into the pin installation hole67by a lateral wall of the large diameter potion5bof the cam member5against a pressing force of the pin spring65.

If the controller90determines that the signal is not a proper signal, the electromagnetic solenoid9does not operate, so that the engagement protruding portion11aof the lock member11is maintained as shown inFIG. 9in a state of being inserted between the first engagement portion53of the slide member51and the lateral wall of the slide groove44, and the rotation preventing portion54of the first engagement portion53prevents the engagement protruding portion11aof the lock member11from entering into the operation groove46, which disables a rotating operation of the rotational member2.

If the controller90determines that the signal is a proper signal, the electromagnetic solenoid9operates to move the lock member11upward for a certain period of time. This releases engagement of the lock member11with the slide member51, and a pressing force of the slide spring49moves the slide member51inside the slide groove44toward the rear side up to an end portion position of the slide groove44where the end portion of the slide member51is in contact with the C ring30. When operation of the electromagnetic solenoid9is completed after a lapse of a certain period of time in this state, the lock member11is lowered by a pressing force of the spring62and inserted into the engagement groove57of the slide member51as shown in FIG.4and FIG.10.

Since the engagement groove57of the slide member51is connected to the operation groove46of the rotational member2in this state, the engagement protruding portion11aof the lock member11will not engage with the slide groove44of the rotational member2if the rotational member2is rotated in a clockwise direction. This enables rotation of the rotational member2and enables operation of the operating knob21for unlocking the steering shaft. If the rotational member2is rotated back from ACC position, ON position or START position to LOCK position, and operation of the operating knob21toward the front side is attempted, the engagement protruding portion11aof the lock member11is engaged with the engagement groove57, and also the slide member51having that engagement groove57is brought into contact with the C ring30so as not to be moved toward the rear side, which makes it impossible to move the rotational member2toward the front side. This prevents a driver from operating the operating knob21toward the front side by mistake.

For unlocking the steering shaft, the operating knob21is rotated by approximately 90 degrees from LOCK position to ACC position. Consequently, as shown inFIG. 6, with aid of the cam portion5cof the cam member5, the following portion7aof the lock shaft7moves against a pressing force of the lock spring69so that a top end portion of the lock shaft7sinks into the body8, which releases engagement between the steering shaft and the lock shaft7. At this point, the pin64of the following portion7amoves under the large diameter potion5bof the cam member5, so that by a pressing force of the pin spring65, the pin64projects toward a lower side of the large diameter potion5b. If the operating knob21is operated in this state to be rotated to LOCK position, engagement of the pin64with the large diameter potion5bis maintained as shown inFIG. 7, and therefore the lock shaft7does not move. Accordingly, once the cam member5, the key cylinder1, and the rotational member2are operated to be in a rear position, and the steering shaft is unlocked, the steering shaft will not be locked no matter if the operating knob21is operated to any rotational position.

When the driver gets out of an automobile, the driver rotates the operating knob21to LOCK position and leaves the automobile with the electronic key, so that the controller90detects the driver leaving and operates the electromagnetic solenoid9for a certain period of time. Eventually, engagement between the engagement protruding portion11aof the lock member11and the engagement groove57of the slide member51is released to enable the rotational member2to move inside the body8in forward and backward directions. Consequently, a pressing force of the spring13moves the cam member5, the key cylinder1, and the rotational member2to a front position. When operation of the electromagnetic solenoid9is completed, the lock member11is returned to a lock state where the engagement protruding portion11athereof is inserted into the slide groove44of the rotational member2and the rotational member2is locked. Here, movement of the cam member5releases engagement of the pin64of the lock shaft7and the large diameter potion5bof the cam member5, and a pressing force of the lock spring69moves the lock shaft7to a side of the steering shaft, by which the steering shaft is locked.

The above structure makes it possible to prevent the steering shaft from being left in an unlocked state since the driver does not need to operate the operating knob21to the front position when getting out of the automobile, and the steering shaft is returned to an initial lock state automatically.

Also, the electromagnetic solenoid9should be operated for just a short period of time until the slide member51is moved to the end portion of the slide groove44by a pressing force of the slide spring49, and therefore required power is also very small.

Next description discusses a case of unlocking the steering lock with use of a key.

When a key is inserted into the key insertion hole17, an inclined portion on a top end of the key comes into contact with the slider25, and attempts to move by pressing the slider25toward an upper side in the state shown in FIG.13A. However, since the engaged member34that is in contact with the slider25is in contact with the inner circumferential wall of the holder4, the slider25cannot be moved. When the key is further pushed in this state, the key cylinder1and the rotational member2move together to the rear position while the inclined portion on the top end of the key and the slider25are in engagement. Consequently, as shown in FIG.12andFIG. 13B, the through-hole33of the rotational member2, the through-hole61of the holder4, and the switch introduction hole60of the body8are linearly connected, as a consequence of which the engaged member34pressed by the slider25escapes from the key cylinder1into the switch introduction hole60and presses the actuating lever15of the key detection switch14to turn the key detection switch14on. At this time, since a contact face between the engaged member34and the slider25is aligned with a contact face between the key cylinder1and the rotational member2, the engaged member34is out of engagement with the key cylinder1. The movement of the slider25to the upper side makes it possible to insert the key completely, and if the key is inserted, the tumblers19sink into the key cylinder1, which enables the key cylinder1to rotate relative to the rotational member2. Further, since the engaged member34is positioned so as to cross over the rotational member2and the holder4, the rotational member2and the holder4are brought into connection with each other.

When the key is extracted from the key cylinder1, the tumblers19of the key cylinder1are returned to a state of projecting from the outer circumferential face of the key cylinder1, and the slider25is also moved to a lower side by a pressing force of the spring27, so that the engaged member34leaves the switch introduction hole60to release connection of the holder4and the rotational member2. Eventually, the spring13moves the rotational member2together with the key cylinder1to the right side ofFIG. 1, by which an initial position of the key cylinder1and the rotational member2is recovered.