JP2952162B2 - Anti-theft mechanism in door lock device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a door lock device, and more particularly to an anti-theft mechanism for improving the security of a door lock device. here,
The anti-theft mechanism is synonymous with the super-lock mechanism or the dead-lock mechanism, and indicates a mechanism that prevents the lock state of the lock device from being released by operating the inside lock button (sill knob) in the vehicle.

[0002]

2. Description of the Related Art A conventionally known door lock device is provided with a lock lever that switches between a locked state (locked state) and an unlocked state (unlocked state). When the lock lever is locked, as is well known, From outside the vehicle, the door cannot be opened without the key (or remote control). However, even if the lock lever is locked, if the window glass is broken and the inside lock button in the room is unlocked, the door is opened without a key or a remote control. On the other hand, Japanese Unexamined Patent Publication
No. 85488, JP-A-2-269281, JP-A-3-158583, US Pat. No. 4,978,15
No. 4 proposes a lock device equipped with an anti-theft mechanism that can disable unlocking of a lock lever by an inner lock button. FIG. 11 is a conceptual diagram of a general lock device with an anti-theft mechanism, where A is an output member that is rotated by a motor M, B is a lock lever that switches the lock device between a locked state and an unlocked state,
C is an anti-theft member for switching the anti-theft mechanism between an anti-theft state and a release state, D is a spring attached to the anti-theft member C, and the spring D includes a coil spring for urging the anti-theft member C to the release position side, and an anti-theft member. 2 of an over-center spring that holds the member C at one of the anti-theft position and the release position with the dead center as a boundary
There are types. In the illustrated device, when the output member A turns to the left to the unlock position X, the lock lever B is unlocked,
When the output member A turns right to the locked position Y, the lock lever B is locked. When the output member A is in the locked position Y
, The anti-theft member C is switched to the anti-theft position while the lock lever B remains in the locked position. The U
The invention described in the specification of SP 4,978,154 also includes
The basic concept is the same as in FIG.

[0003]

In the lock device with an anti-theft mechanism as shown in FIG. 11, when only the lock lever B is locked, the output member A is securely locked at the locking position Y.
Must be stopped at. For this reason, conventionally, a sensor or the like is attached to the output member A, and when the output member A is at the locked position Y, the sensor or the like detects this and the motor M
The power supply to is stopped. However,
Even if a sensor or the like is used, the power supply to the motor M can be surely stopped, but the rotation of the motor M cannot be surely stopped. In other words, even if the power is turned off, the output member A also rotates beyond the locking position Y because the motor M slightly rotates due to inertia. It can happen. When the applicant conducted an experiment using a prototype (this prototype is a product having the structure described in the embodiment of the present application), such erroneous switching as described above could not be completely prevented. One of the causes of the erroneous switching is that the voltage of the battery that drives the motor M greatly changes. As the voltage increases, the excess rotation increases and erroneous switching occurs. In anticipation of such an abnormal rise in voltage, it is conceivable to set the circuit of the motor M, the reduction ratio, and the like in advance in accordance with a higher voltage.
When the battery voltage drops, the rotational force of the motor M loses the elasticity of the spring D, and the switching of the anti-theft member C may not be possible. That is, assuming a lower voltage, switching to anti-theft cannot be performed, and assuming a higher voltage, erroneous switching to anti-theft occurs.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a lock lever 1 which is connected to a door key cylinder 14 and an inner lock button 26 and switches between a locked position and an unlocked position.
3, an anti-theft member 29 that switches between an anti-theft position that disables the unlocking operation of the lock lever 13 by the inner lock button 26, and an anti-theft position and a release position thereof. A motor 4 capable of switching the anti-theft member 29 to the anti-theft position when the normal rotation is continued beyond a predetermined amount;
A control unit 46 having locking control for switching the lock lever 13 to a locked position by the motor 4 and anti-theft control for switching the anti-theft member 29 to the anti-theft position by the motor 4; a battery 52; the battery 52; And a voltage switching circuit 53 that can supply a different drive voltage to the motor 4.
The voltage switching circuit 53 is an anti-theft mechanism in a door lock device configured so that the driving voltage when the control unit 46 performs the locking control is lower than the driving voltage when the anti-theft control is performed. It is. Further, in the present invention, in the above, the voltage switching circuit 53 has a high voltage circuit H switched based on a command from the control unit 46 and a low voltage circuit L having a circuit resistance larger than the high voltage circuit H. This is an anti-theft mechanism in a door lock device.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings.
Reference numeral 1 denotes a fan-shaped output member rotatably supported by a center shaft 2, and a gear portion 3 formed on the outer periphery thereof has a motor 4
(Not shown). On the upper surface of the output member 1, an arc groove 5 centering on the center axis 2 is formed as shown in FIG. 2, and a neutral return spring 6 is housed in the arc groove 5. When the motor 4 is not rotating (non-energized), the output member 1
1 is held at the neutral position shown in FIG. 1 by the elasticity of the neutral return spring 6, and when the motor 4 is energized and rotates forward, the neutral return spring 6 passes from the neutral position in FIG. Then, the motor 4 rotates rightward to the anti-theft point II which comes into contact with the stopper 7, and conversely, when the motor 4 reversely rotates, it turns leftward from the neutral position to the unlock point IV which comes into contact with the stopper 8 via the anti-theft release point III.

An interlocking shaft 9 is provided in the vicinity of the output member 1, and a different diameter portion 10 of the interlocking shaft 9 is engaged with a different diameter hole 12 of an interlocking lever 11. The interlocking shaft 9 is a lock lever 1 that switches between a locked position and an unlocked position of the door lock device.
3 (FIG. 2), so that the lock lever 13 and the interlocking lever 11 are displaced in conjunction with each other. Reference numeral 14 denotes a door key cylinder for switching the lock lever 13 between a locked position and an unlocked position.

On the front side of the interlocking lever 11, a rectangular parallelepiped projection 15 and a rod-shaped projection 16 further projecting from the top of the projection 15 are formed. The projection 16 is provided on the output member 1.
In the cam groove 17 formed on the rear side of the cam. When the output member 1 rotates left and right from the neutral position, the protrusion 16 is pressed by the cam groove 17 and rotates about the interlocking shaft 9. This relationship will be described in more detail with reference to FIG. 1. The cam groove 17 basically includes an arc-shaped inner peripheral wall 18 and an outer peripheral wall 19 having an arc shape centered on the central axis 2.
And a right cam wall 20 and a left cam wall 21, and an intersecting portion between the outer peripheral wall 19 and the right cam wall 20 is provided with an idling groove 22 extending on an arc locus centered on the central axis 2. . As described above, the interlocking lever 11 interlocking with the lock lever 13 is at the position shown in FIG. 1 when the lock lever 13 is in the unlocked position, and the protrusion 16 of the interlocking lever 11 is in contact with the inner peripheral wall 18 as shown by a solid line. It is located at a first corner portion 23 formed between the right cam walls 20. In this state, when the output member 1 is rotated rightward to the lock point I by the motor 4,
The right cam wall 20 engages with the projection 16 to turn the interlocking lever 11 to the left, displacing the projection 16 to the locked position shown by the imaginary line, whereby the lock lever 13 is also interlocked and switched to the locked position.

On the other hand, when the output member 1 is at the neutral position, the projection 16 at the locked position shown by a virtual line in FIG. 1 is formed between the outer peripheral wall 19 and the left cam wall 21. It is located far away from the second corner 24,
When the output member 1 is turned to the left to the release point III, the protrusion 16 is in contact with the second corner portion 24. For this reason, even when the output member 1 turns left from the neutral position to the release point III, the interlocking lever 11 does not rotate. 1
Turn 1 to the right, and when it reaches unlock point IV, interlock lever 11
Switches to the unlocked position. The reason for separating the second corner portion 24 at the neutral position and the projection 16 at the locked position is as follows.
This is for canceling the anti-theft state described later. When the output member 1 exceeds the lock point I and the anti-theft point II
When turned to the right, the projection 16 enters the idle vibration groove 22 as shown in FIG.

Reference numeral 25 denotes a hollow shaft connected to an inner lock button 26 of the door. The hollow shaft 25 is rotatably inserted into a small-diameter shaft 27 on the upper end side of the interlocking shaft 9. The hollow shaft 25 is integrally formed with a radially protruding key portion 28, and the fork portion 30 formed at one end of the anti-theft member 29 is slidably engaged with the key portion 28. The other end of the anti-theft member 29 is provided with a hook 32 in the form of a fishing hook having an opening 31 formed in a side surface, and the projection 15 of the interlocking lever 11 faces the inside of the hook 32.

Although a specific method of sliding the anti-theft member 29 will be described later, when the anti-theft member 29 slides with respect to the key portion 28, as shown in FIG. As shown in FIG. 5, the state is switched to a state in which the protrusion 15 is separated from the hook 32 and faces the opening 31. In a state where the hook 32 and the convex portion 15 are engaged, when the hollow shaft 25 is rotated by operating the inner lock button 26, the anti-theft member 29 is rotated by the engagement between the key portion 28 and the forked portion 30, whereby the anti-theft member 29 is rotated. The interlocking lever 11 rotates, so that the lock lever 13 can be switched via the interlocking shaft 9. That is, hook 3
When the projection 2 and the projection 15 are engaged, the inner lock button 26 and the lock lever 13 are connected, and the lock lever 13 can be freely switched by operating the inner lock button 26. However, in a state where the convex portion 15 faces the opening portion 31 of the hook 32 as shown in FIG. 5, even if the anti-theft member 29 is turned to the right, the hook 32 does not engage with the convex portion 15 and swings, so that the interlocking lever 11 is moved. It cannot be rotated. That is, when the inner lock button 26 is operated,
The lock lever 13 in the locked position cannot be displaced to the unlocked position. This idling mechanism is the anti-theft mechanism of the present application, and the anti-theft member 29 has the anti-theft position at the position in FIG. 5 or the release position (non-anti-theft position) at the position in FIG.

On the back side of the interlocking lever 11, a switching body 33 rotatably supported by the center shaft 2 for switching an anti-theft state is provided. The switching body 33 is preferably formed of a thin metal plate, and locks one end of the over-center spring 34 at a desired position of the switching body 33 so that the switching body 33 is separated from the dead center of the over-center spring 34. 3 is switched to one of the non-operation position in FIG. 3 and the operation position in FIG.

A substantially triangular engagement hole 35 is formed in the switching body 33, and an engagement pin 36 formed in the anti-theft member 29 is engaged with the engagement hole 35. When the switching body 33 is in the non-operation position shown in FIG. 3, the anti-theft member 29 is slid to the right by the engagement between the engagement hole 35 and the engagement pin 36 and is held in the non-anti-theft position. Is moved to the operating position beyond the dead center of the over center spring 34, the anti-theft member 29
5 is displaced to the anti-theft position in FIG. 5 by sliding to the left by engagement of the engagement pin 36 with the engagement pin 36.

The switching member 33 is formed with a bent piece 37 which can be engaged with the side surface of the output member 1. In the state of FIG. 4, the output member 1 turns right over the lock point I toward the anti-theft point II. Then, the side surface of the output member 1 is engaged with the bent piece 37 to switch the switching body 33 from the non-operation position to the operation position against the elasticity of the overcenter spring 34, whereby the anti-theft member 29 is displaced to the anti-theft position. .

In summary, in the present application, when the output member 1 rotates to the lock point I, the interlocking lever 11 (the lock lever 13) is locked by the engagement between the right cam wall 20 and the projection 16. When the output member 1 is rotated to the anti-theft point II beyond the lock point I, the switching body 33 is displaced to the operating position, and the engagement hole 35 and the engagement pin 3 are displaced.
6, the anti-theft member 29 is displaced to the anti-theft position.

Reference numeral 38 denotes a release lever for returning the switching body 33 from the operating position to the non-operating position by the power of the motor 4, and is rotatably supported by a shaft 39. A projection 40 is formed on the rotation end side of the release lever 38, and the projection 40 is
The engagement lever 38 is engaged with the long hole 41 formed in the third member 3, and the release lever 38 and the switching body 33 are connected so as to interlock with each other. Release lever 38
Is provided with an engagement piece 43 which can be engaged with a drop-shaped convex portion 42 formed on the back side of the output member 1. As shown in FIG. 6, the engagement piece 43 and the projection 42 are substantially in contact with each other when the switching body 33 is at the operating position and the output member 1 is held at the neutral position. When the member 1 is turned to the left to the release point III, the convex portion 42 engages with the engagement piece 43 and turns the release lever 38 to the right around the shaft 39. The anti-theft member 29 is switched from the anti-theft position to the release position. Even if the output member 1 is turned to the left to the release point III, the cam groove 1
Since the left cam wall 21 of 7 does not engage with the projection 16 of the interlocking lever 11, the interlocking lever 11 remains in the locked position and is not unlocked, and the output member 1 moves beyond the release point III to the unlock point IV. When turning to the left, the interlocking lever 11 moves to the left cam wall 21
Turns right and is displaced to the unlock position.

The engagement between the projection 42 and the engagement piece 43 is as follows.
The output member 1 is released halfway from the neutral position to the left to reach the release point III, but at this time, since the switching body 33 is beyond the dead center of the overcenter spring 34, the switching body 33 is reliably moved by the elasticity of the overcenter spring 34. To the inactive position.

Reference numeral 44 denotes another substantially triangular engagement hole formed in the switching body 33.
The engaging pin 45 formed in 1 is engaged. Engaging pin 45
When the interlocking lever 11 is turned to the right in the anti-theft state shown in FIG. 6, the switch 33 is switched from the operating position to the non-operating position by engaging with the engagement hole 44. This means that key cylinder 1
When the lock lever 13 (and the interlocking lever 11) is switched to the unlocking position by operating the unlocking operation of the anti-theft member 29, the switching body 33 is switched from the operating position to the non-operating position. Means that it can be restored at the same time.

FIG. 9 is a control block diagram of the present invention, in which 46 is a control section, 47 is a lock sensor for detecting the position of the lock lever 13 (interlocking lever 11), and 48 is a switching body 33 (anti-theft member 29). ) Is an anti-theft sensor for detecting the position, 49 is a key switch switched by operating the key cylinder 14, and 50 is a receiving unit of the remote controller 51. The control unit 46 controls the output member 1 by the motor 4.
Is controlled to rotate the lock lever 13 to the lock position by rotating the lock member 13 to the lock point I, and the output member 1 is controlled by the motor 4.
Is rotated to the anti-theft point II and the anti-theft member 2
An anti-theft control for switching the anti-theft member 29 to the anti-theft position, a release control for rotating the output member 1 to the release point III by the motor 4 and switching the anti-theft member 29 to the release position while keeping the lock lever 13 in the locked position,
Unlock control for rotating the output member 1 to the unlock IV by the motor 4 and switching the lock lever 13 to the unlock position.

FIG. 10 is a circuit diagram showing a voltage switching circuit 53 according to the gist of the present invention. The voltage switching circuit 53 supplies at least two different power supply voltages to the motor 4. The voltage switching circuit 53 includes a battery 52
A high-voltage circuit H that supplies the voltage of
The battery 52 is connected to the motor 4 via a resistor 54 having an appropriate value.
, And a voltage changeover switch 55 that is switched by a command from the control unit 46, and has a feature that it can be configured at extremely low cost. In FIG. 10, reference numeral 56 denotes a rotation direction changeover switch for the motor 4, and 57 denotes a main switch. Note that the voltage switching circuit 53 shown in FIG. 10 is merely an example, and is somewhat expensive.
The voltage supplied to the motor 4 may be changed using a DC converter or the like.

[0020]

FIGS. 1 and 3 show the unlocked state. In this state, when a locking operation command is given to the control unit 46 by the key cylinder 14 or the remote controller 51, the control unit 46 operates the rotation direction switch 56. After the voltage changeover switch 55 is switched to the low voltage circuit L side in the normal rotation direction, the main switch 57 is turned on to cause the motor 4 to rotate forward.
Then, the output member 1 is turned rightward from the neutral position in FIG. 3, and the right cam wall 20 of the cam groove 17 formed on the back side of the output member 1.
Presses the projection 16 of the interlocking lever 11 to move the interlocking lever 1
When the output member 1 is turned to the left and the output member 1 is rotated to the lock point I, the interlocking lever 11 is displaced to the locked position (FIG. 4). When the interlocking lever 11 is displaced to the locked position, the lock lever 1
3 is connected to the interlocking lever 11 via the interlocking shaft 9 and is displaced to the locking position in interlocking with the interlocking lever 9.
The anti-theft member 29 connected to the interlocking lever 11 by the engagement of the
5, the inner lock button 26 connected to the hollow shaft 25 is displaced to the locked position. When the lock sensor 47 detects the lock point I of the output member 1, the control unit 46 turns off the main switch 57 to stop energizing the motor 4, whereby the output member 1 is turned on by the elasticity of the neutral return spring 6. Return to neutral position.

In the switching to the locked state, the motor 4 receives power supply through the low-voltage circuit L whose circuit resistance is increased by the resistor 54, so that the voltage applied to the motor 4 decreases and its rotational force decreases. Because it is somewhat refrained,
The rotation due to the inertia after the power supply is cut off is also small, whereby the malfunction in which the output member 1 rotates to the anti-theft point as described in the related art can be completely suppressed.

When switching from the unlocked state to the anti-theft state, the key cylinder 14 or the remote controller 5
When an operation command for anti-theft is given to the control unit 46 by 1, the control unit 46 switches the rotation direction changeover switch 56 to the normal rotation direction and the voltage changeover switch 55 to the high voltage circuit H side and then turns on the main switch 57. To rotate the motor 4 forward. Then, the output member 1 turns rightward from the neutral position, and when the output member 1 rotates to the lock point I as described above, the interlocking lever 11 (lock lever 13) is switched to the locked position. Is further rotated, the side surface of the output member 1 comes into contact with the bent piece 37 of the switching body 33, and displaces the switching body 33 to the operating position side against the elasticity of the over center spring 34. Then, switching body 3
The anti-theft member 29 in which the engaging pin 36 is engaged with the engaging hole 35 of the third slide from the position of FIG. 4 to the left as shown in FIG. The opening 31. In this state,
Even if the anti-theft member 29 is turned to the right by the unlocking operation of the inner lock button 26, the interlocking lever 11 does not rotate because the hook 32 does not engage with the convex portion 15 and swings, so the lock lever 13 is unlocked. You will not be able to. When the anti-theft sensor 48 detects the operating position of the switching body 33, the control unit 46 stops energization of the motor 4, whereby the output member 1 returns to the neutral position by the elasticity of the neutral return spring 6 ( (Fig. 6).

In the switching to the anti-theft state, the motor 4 is supplied with power via the high voltage circuit H having a lower circuit resistance than the low voltage circuit L, so that the voltage applied to the motor 4 is increased and its rotational force is reduced. This is larger than the time of the locking control, so that the switching failure of the switching body 33 does not occur due to the resilience of the over-center spring 34.

To release the anti-theft state shown in FIG. 6, the output member 1 is turned to the left by the motor 4. Then
Since the projection 42 of the output member 1 pushes the engagement piece 43 of the release lever 38, the release lever 38 turns right around the shaft 39, and the switching body 33 turns left by engagement of the projection 40 and the elongated hole 41. And
When the output member 1 reaches the release point III in FIG. 7, the switching body 33 is displaced to the inoperative position side beyond the dead center of the over center spring 34, and the anti-theft member 29 slides to the release position. Even if the output member 1 rotates to the release point III as shown in FIG. 7, the left cam wall 21 of the cam groove 17 is
Since the one projection 16 is not pressed, the interlocking lever 11 is not displaced in the locked position.

As described above, the output member 1 is connected to the release point in FIG.
When the switching body 33 is turned to the left to III, the switching body 33 returns to the non-operation position side, so that the anti-theft sensor 48 detects this. When only the anti-theft release command is received, the control unit 46 stops the power supply to the motor 4 based on this detection, and returns the output member 1 to the neutral position by the elasticity of the neutral return spring 6. That is, only the anti-theft is released without unlocking the lock lever 13. However, when receiving the unlock command of the lock lever 13, the control unit 46 continues to supply power to the motor 4 and unlocks the output member 1 even if the anti-theft sensor 48 detects the displacement of the switching body 33. Rotate to point IV. Then, the left cam wall 21 of the cam groove 17 presses the projection 16 of the interlocking lever 11, and the interlocking lever 11 can be turned rightward to return to the unlocked position.

[0026]

As described above, according to the present invention, the lock lever 13 connected to the key cylinder 14 and the inner lock button 26 of the door and switched between the locked position and the unlocked position, and the lock lever by the inner lock button 26 are provided. An anti-theft member 29 that switches between an anti-theft position that disables the unlocking operation of the anti-theft 13 and a release position thereof; and a forward rotation of a predetermined amount switches the lock lever 13 to a locking position. Member 29
And a lock control for switching the lock lever 13 to a lock position by the motor 4 and the anti-theft member 2 by the motor 4.
A control unit 46 having anti-theft control for switching 9 to an anti-theft position; a battery 52; and a voltage switching circuit 53 provided between the battery 52 and the motor 4 and capable of supplying a different drive voltage to the motor 4. The voltage switching circuit 53 is an anti-theft mechanism in a door lock device configured so that the drive voltage when the control unit 46 performs the lock control is lower than the drive voltage when the anti-theft control is performed. Since the drive voltage for rotating the motor 4 forward by the control is set to be low, it is possible to suppress the excessive rotation after stopping the energization.
The switching to the anti-theft state is not erroneously performed, and the drive voltage for the anti-theft control is set to be high. Further, in the present invention, in the above, the voltage switching circuit 53 has a high voltage circuit H switched based on a command from the control unit 46 and a low voltage circuit L having a circuit resistance larger than the high voltage circuit H. Since the anti-theft mechanism is used in the door lock device, an effect that can be implemented with a simple and inexpensive circuit simply by adding a resistor is achieved.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between an output member and an interlocking lever.

FIG. 2 is an exploded perspective view.

FIG. 3 is an unlocked state diagram.

FIG. 4 is a state diagram in which the output member is rotated to a lock point I.

FIG. 5 is a state diagram in which the output member is rotated to an anti-theft point II.

FIG. 6 is an anti-theft state diagram.

FIG. 7 is a state diagram in which the output member is rotated to a release point III.

FIG. 8 is a state diagram in which the output member is rotated to an unlock point IV.

FIG. 9 is a block circuit diagram.

FIG. 10 is a circuit diagram including a voltage switching circuit.

FIG. 11 is a diagram of a known example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Output member, 2 ... Center shaft, 3 ... Gear part, 4 ... Motor,
5 ... arc groove, 6 ... neutral return spring, 7, 8 ... stopper,
9 ... interlocking shaft, 10 ... different diameter part, 11 ... interlocking lever, 12 ...
Different diameter holes, 13: Lock lever, 14: Key cylinder, 1
5: convex portion, 16: protrusion, 17: cam groove, 18: inner peripheral wall, 19: outer peripheral wall, 20: right cam wall, 21: left cam wall, 22: idle vibration groove, 23: first corner portion, 24 ... second
Corner part, 25: hollow shaft, 26: inside lock button,
27 small diameter shaft, 28 key part, 29 anti-theft member, 30 bifurcated part, 31 opening, 32 hook, 33
... Switching body, 34 overcenter spring, 35 engagement hole, 36 engagement pin, 37 bending piece, 38 release lever, 39 axis, 40 projection, 41 elongated hole, 42 convex part,
43 ... engaging piece, 44 ... engaging hole, 45 ... engaging pin, 46 ...
Control unit 47 Lock sensor 48 Anti-theft sensor 49 Key switch 50 Receiver 51 Remote controller 52 Battery 53 Voltage switching circuit 54
... Resistance, 55 ... Voltage changeover switch, 56 ... Rotation direction changeover switch, 57 ... Main switch, H ... High voltage circuit, L
... low voltage circuit.

Claims (2)

(57) [Claims] A lock lever connected to a door key cylinder and an inner lock button for switching between a locked position and an unlocked position, and the unlock operation of the lock lever by the inner lock button is disabled. An anti-theft member 29 that switches between an anti-theft position and a release position thereof;
The motor 4 is capable of switching the anti-theft member 29 to the anti-theft position when the normal rotation is continued beyond the predetermined amount by switching to the locking position, the locking control for switching the lock lever 13 to the locking position by the motor 4, and the motor 4. A control unit 46 having anti-theft control for switching the anti-theft member 29 to the anti-theft position; a battery 52; and a voltage switching circuit provided between the battery 52 and the motor 4 and capable of supplying a different drive voltage to the motor 4 53. The anti-theft mechanism in the door lock device, wherein the voltage switching circuit 53 is configured to make the drive voltage when the control unit 46 performs the locking control lower than the drive voltage when performing the anti-theft control. 2. The voltage switching circuit according to claim 1,
Reference numeral 3 denotes an anti-theft mechanism in a door lock device having a high-voltage circuit H switched based on a command from the control unit 46 and a low-voltage circuit L having a circuit resistance greater than the high-voltage circuit H.