JP2002004678A - Door lock device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further heighten fail safe to unlatch of a latch mechanism by adopting a triple driving system in a current path of a motor as a driving source. SOLUTION: An Hi side drive element 90, a DC motor M, both unlatch switches 10 and 20, and a Lo side drive element 100 are connected in series. When one of both, unlatch switches 10, 20 is turned on in the on-state of the Hi side drive element 90 and Lo side drive element 100, a current flows from a battery to the DC motor M to unlatch the latch mechanism of the door lock mechanism L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle door lock device.

[0002]

2. Description of the Related Art In recent years, for example, along with the electronic control of a latch mechanism of a door lock device for a passenger car, there is a demand for establishing fail-safe for unlatch of the latch mechanism, and eventually fail-safe for opening a door of the passenger car.
In response to this, for example, as disclosed in US Pat. No. 5,777,395, an unlatch switch interlocked with the operation of an inner handle or an outer handle of a door,
By electrically connecting a relay switch that operates when the door unlock condition is satisfied to the DC motor of the door lock device in series, there is no operation of the handle or the door unlock condition must be satisfied. For example, there is a configuration in which unlatching by a latch mechanism is not performed.

[0003]

By the way, in the above door lock device, the current path of the DC motor is provided with a fail-safe dual drive system including both an unlatch switch and a relay switch. If a double failure occurs (short failure of both the unlatch switch and the relay switch), the unlatch of the latch mechanism
A situation arises where it is not possible to unlatch and cannot meet the demand for failsafe establishment.

In view of the above, the present invention employs a triple drive system in a current path of a motor as a driving source of a door lock device for a vehicle to solve the above-mentioned problem, thereby preventing the latch mechanism from unlatching. The purpose is to further enhance fail-safe.

[0005]

In order to solve the above-mentioned problems, a vehicle door lock device according to the first aspect of the present invention includes an electric motor (M) that operates by being supplied with electric power from a power supply.
A door lock mechanism (L) including a latch mechanism driven by the electric motor to enter a latched state or an unlatched state; a lock operation means (40) for operating the door when locking or unlocking; Door handle (Ho, H
An unlatch switch (10, 20,) for operating a switch in conjunction with i) and releasing the switch operation by releasing the operation of the steering wheel, and a first and a second switching element ( 9
0, 100), a detecting means (51) for detecting a stop state of the vehicle, a first switching element is turned on based on the detection of the detecting means and an unlock operation of a lock operating means, and based on a switch operation of an unlatch switch. Control means (2) for controlling to turn on the second switching element
10, 220, 222, 231), and the door lock mechanism puts the latch mechanism into the unlatched state in accordance with the operation of the motor in accordance with the power supply from the power supply to the motor under the control of the control means.

As described above, the motor is connected in series with the first and second switching elements and the unlatch switch. Therefore, when the unlatch switch operates in the on state of the first and second switching elements, the door lock mechanism is supplied with power from the power supply by the electric motor, and the latch mechanism is brought into the unlatched state.

Therefore, in a state where the first and second switching elements are turned off and the unlatch switch is released from the switch operation, any one of the three elements of the first and second switching elements and the unlatch switch is used. Even if one of the elements is short-circuited, the latch mechanism will not be in the unlatched state if the remaining one element is normal.

As described above, by adopting the triple drive system of the first and second switching elements and the unlatch switch in the current path of the motor, the fail-safe of the latch mechanism with respect to the unlatch can be further enhanced.

According to a second aspect of the present invention, in the first aspect, the second switching element and the motor are connected in series between an unlatch switch and a power supply, and the unlatch switch connects the first switching element. A first driving means (81) for driving the second switching element intermittently for a short period of time while the motor is maintained in a non-operating state;
And turning on the second switching element for a predetermined time when the voltage generated between the second switching element and the motor and the unlatch switch is reduced by the switch operation of the unlatch switch in the on state of the first and second switching elements. A second driving means (70, 82).

As described above, when the voltage generated between the second switching element and the motor and the unlatch switch decreases in accordance with the switch operation of the unlatch switch in the intermittent ON state of the second switching element, the second switching element is turned on for a predetermined time. Was turned on for a while. This ensures the unlatched state of the latch mechanism,
The operation and effect of the invention described in claim 1 can be achieved.

According to a third aspect of the present invention, in the second aspect of the present invention, the second driving means includes a monitoring means (70) for monitoring the voltage, and monitoring of the voltage drop by the monitoring means. Accordingly, a timer means (82) for turning on the second switching element for a predetermined time is provided. Thereby, the operation and effect of the invention described in claim 2 can be achieved with a simple circuit configuration.

The reference numerals in parentheses of the above-mentioned means indicate the correspondence with the concrete means described in the embodiments described later.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIG. FIG. 1 shows a door lock device for a passenger car according to the present invention. The door lock device includes a door lock mechanism L and a control device E.

The door lock mechanism L is provided in a lower part of the door of the passenger car. The door lock mechanism L includes a striker fixed to an inner wall at a lower part of the door, a latch detachable from the striker, The locking plate includes a locking plate that can be disengaged from the latch, and an actuator that drives the locking plate. In addition, striker,
The latch and the locking plate constitute a latch mechanism of the door lock mechanism L.

The actuator moves the locking plate in the release direction in accordance with the rotation of the DC motor M to release the engagement between the latch and the striker (unlatching of the latch mechanism). When the locking plate is in the non-released state, the latch and the striker are in the engaged state (the latch state of the latch mechanism).

As shown in FIG. 1, the control device E includes an outer unlatch switch 10 and an inner unlatch switch 20 operatively connected to the outer handle Ho and the inner handle Hi of the door, respectively.

The outer unlatching switch 10 is turned on in response to the operation of the outer handle Ho, and the outer handle Ho is turned on.
It turns off when it returns to its original position when the operation is released. The inner unlatching switch 20 is turned on in response to the operation of the inner handle Hi, and turned off when the inner handle Hi is returned to the original position in response to the operation release. The two unlatch switches 10 and 20 are connected in parallel with each other and are connected in series with the DC motor M.

The control device E includes a full latch switch 30
And a self-door lock switch 40 in the passenger car. The full latch switch 30 is turned on only when the latch enters the unlatched state with the rotation of the DC motor M. The door lock switch 40 is
This is a switch for performing a lock operation when the door corresponding to the driver's seat among the doors of the passenger car is to be locked, and performing an unlock operation when the door is to be unlocked.

The control device E includes the signal processing circuits 50 and 6
0, 70, and the signal processing circuit 50 includes an electronic control unit 50a (hereinafter referred to as an ECU 5) mounted on the passenger car.
0a) from the vehicle speed sensor 51 and output the signal to the microcomputer 80 after signal processing. Further, the signal processing circuit 50 performs signal processing on a door lock or unlock instruction from the ECU 50 b and outputs the processed signal to the microcomputer 80.

The vehicle speed sensor 51 detects the vehicle speed of the passenger car. The signal processing circuit 60 includes the full latch switch 30
And the output of the self door lock switch 40 are signal-processed and output to the microcomputer 80. When either of the two unlatch switches 10 and 20 is turned on, the signal processing circuit 70
The signal generated at the common terminal between the two is signal-processed and output to the microcomputer 80.

The microcomputer 80 executes a computer program according to the flowchart shown in FIG. 2, and during this execution, the signal processing circuits 50, 60,
70 and the data stored in the EEPROM 80a, and the Hi-side drive element 9 via the OR gate 80b.
0 to control the Lo side drive element 100,
Further, the light emitting diode 120 (hereinafter, referred to as LED 120) is controlled via the driving circuit 110. The computer program is stored in the ROM of the microcomputer 80 in advance.

The EEPROM 80a stores either a door locked state or an unlocked state as data according to the processing of the microcomputer 80. OR gate 8
0b is a clock 8 built in the microcomputer 80.
1 and the output of the timer 82 are set to Hi.
Output to the side drive element 90. The clock 81 generates a clock pulse at a predetermined frequency. Timer 82
Is reset-started based on the output of the signal processing circuit 70 (corresponding to either of the unlatch switches 10 and 20 being turned on when the Lo side drive element 100 is turned on), and measures a predetermined time T (see FIG. 2). .

The Hi-side drive element 90 is composed of a MOS field-effect transistor. The Hi-side drive element 90 is connected at its source to the positive terminal + B of the battery, and has its drain connected to the DC motor M. DC motor M and both unlatch switches 10, 2
0 is connected to a common terminal. The Hi-side drive element 90 has an OR gate 80b at its gate.
Output terminal.

Thus, the Hi-side drive element 90
Is turned on repeatedly and instantaneously by sequentially inputting clock pulses from the OR gate 80b, and is turned on for a predetermined time T by inputting the output of the timer 82 from the OR gate 80b. The frequency of the clock pulse is set to such an extent that the DC motor M does not rotate even when the Hi-side drive element 90 is turned on by the clock pulse from the OR gate 80b.

The Lo-side drive element 100 is composed of a MOS field-effect transistor. The Lo-side drive element 100 has a source connected to a common terminal of the unlatch switch with the DC motor M via the two unlatch switches 10 and 20 at its source. It is connected to the. This means that the Lo side drive element 100, the two unlatch switches 10, 20, the DC motor M, and the Hi side drive element 90 are connected in series with each other.
Further, the Lo side drive element 100 is grounded at its drain, and
The gate of 0 is connected to the microcomputer 80. As a result, under control of the microcomputer 80, the Lo side drive element 100 is turned on to ground both unlatch switches 10 and 20, and is turned off to release grounding of both unlatch switches 10 and 20.

The driving circuit 110 is composed of a transistor.
Under the control of 0, the LED 120 emits light when turned on and stops emitting light when turned off.

In this embodiment configured as described above, when the passenger car is in a running state and the microcomputer 80 starts executing the computer program according to the flowchart of FIG. 2, the output processing of the clock 81 is performed in step 200. You. Accordingly, the clock 81 sequentially outputs the clock pulse to the gate of the Hi-side drive element 90 through the OR gate 80b.

Thus, the Hi-side drive element 9
0 is repeatedly turned on instantly (see FIG. 3). When both the unlatch switches 10 and 20 are off, the common terminal of the DC motor M and the two unlatch switches 10 and 20 connects to the internal circuit of the DC motor M and Hi side drive element 9
It conducts to the positive terminal + B of the battery via 0. Thus, the voltage of the common terminal substantially becomes the voltage of the positive terminal + B of the battery every time the Hi-side drive element 90 is turned on instantaneously. For this reason, the timer 82 does not start counting time by the output of the signal processing circuit 70.

Next, in step 201, the EEPR
The data stored in the OM 80a is read. This allows
The microcomputer 80 recognizes whether the content of the data stored in the EEPROM 80a is locked or unlocked. The reading of the stored data from the EEPROM 80a is performed only when the power is turned on.

Next, in step 210, it is determined based on the output of the signal processing circuit 60 whether or not the door has been locked or unlocked at this stage. If the operation has been performed, step 210
Is YES, and in step 211, the door lock state and the unlock state transition processing corresponding to the operation is performed.
0a is stored and updated as data.

If the determination in step 210 is NO, or if the process in step 212 is performed,
In step 213, the light emission of the LED 120 or its stop processing is performed. Specifically, in the unlocked state, the light emitting process of the LED 120 is performed. Accordingly, the drive circuit 110 causes the LED 120 to emit light. On the other hand, in the locked state, the light emission stop processing of the LED 120 is performed. As a result, the driving circuit 110
Light emission of 0 is stopped.

Thereafter, in step 220, it is determined based on the respective outputs of the two signal processing circuits 50 and 60 whether the unlocked state, the stopped state, and the full latch switch 30 are both off. Here, the signal processing circuit 5
The output of 0 does not correspond to the stop state of the passenger car (the detection output of the vehicle speed sensor 51 corresponds to the vehicle speed of zero), or the output of the signal processing circuit 60 turns off the full latch switch 30 or unlocks the door lock switch 40 for the passenger seat. If it does not correspond to the operation, the determination in step 220 is NO,
In step 221, the Lo side drive element 10
0 off processing is performed. For this reason, since the Lo side drive element 100 does not turn on, the timer 82 keeps time by the output of the signal processing circuit 70 even if either of the two unlatch switches 10, 20 is turned on by operation of either of the handles Ho, Hi. Never start. Thereby, the unlatch prohibited state can be maintained.

On the other hand, the determination in step 220 is YE
When S is reached, in step 222, the Lo side drive element 100 is turned on. Accordingly, L
o The side drive element 100 is a microcomputer 8
It is turned on by 0. Accordingly, both the unlatch switches 10 and 20 are grounded by the Lo side drive element 100 at the terminal on the Lo side drive element 100 side.

In such a state, both handles Ho, H
When one of the two unlatch switches 10, 20 is turned on by one operation of i, the common terminal of both the unlatch switches 10, 20 and the DC motor M is grounded via the Lo side drive element 100. Therefore, the signal output circuit 70
Output goes low. This low-level output is input from the signal output circuit 70 to the microcomputer 80 in step 223.

Next, at step 230, it is determined whether or not the unlatch switch is on. As mentioned above,
Since the low level of the output of the signal output circuit 70 indicates that the unlatch switch is on, a determination of YES is made in step 230. Then, in step 231, a reset start process of the timer 82 is performed. At the same time, the timer 82 starts counting the predetermined time T, and at the same time, generates a timer signal at a high level and inputs the timer signal to the gate of the Hi-side drive element 90 through the OR gate 80b (see FIG. 3). As a result, the Hi-side drive element 90 turns on.

As described above, the two unlatch switches 10,
When one of the switches 20 is turned on and both the Lo-side drive element 100 and the Hi-side drive element 90 are turned on, the battery current is turned on among the Hi-side drive element 90, the DC motor M, and the two unlatch switches 10 and 20. It flows through the unlatch switch and the Lo side drive element 100 (see FIG. 3). For this reason, the door lock mechanism L puts the latch into the unlatched state according to the rotation of the DC motor M.

Step 2 after processing in step 231
Based on the determination of NO at 40, it is determined at step 250 whether the full latch switch is on. If the determination in step 250 is YES, in step 251 the Lo side drive element 100 is turned off, and the Lo side drive element 10 is turned off.
0 turns off.

When the time counted by the timer 82 has passed the predetermined time T based on the determination of NO in step 250,
The determination in step 240 becomes YES, and step 24
At 1, the timer 82 is stopped. Thus, the timer 82 stops outputting the timer signal due to the stop.

Here, the Hi-side drive element 90, at least one of the two unlatch switches 10, 20, and L
Even if two of the three drive elements of the o-side drive element 100 are short-circuited (double fault), if the remaining drive elements are normal, the latch does not go into the unlatched state.

In other words, in the door lock device, a triple drive system including the Hi-side drive element 90, the two unlatch switches 10, 20 and the Lo-side drive element 100 is employed in the current path of the DC motor M as the drive source. By doing so, failsafe from unlatch due to short-circuit failure of two or less drive elements of the triple drive system of the latch can be further enhanced.

As described above, the common terminal of the DC motor M and the two unlatch switches 10 and 20 is connected via the Hi-side drive element 90 to the positive terminal of the battery.
B, and the Hi-side drive element 90 is turned on by the clock pulse of the clock 81 of the microcomputer 80, so that the Hi-side drive element 90 is used as a sampling power source for the signal processing circuit 70. With the circuit configuration, the unlatch in the door lock device can be secured with good timing.

In the embodiment of the present invention, the Hi-side drive element 90 is not limited to the MOS field-effect transistor, but may be a bipolar transistor. The Lo side drive element 100 is not limited to a MOS field effect transistor, but may be a bipolar transistor or a relay. In addition,
When using a relay, through the relay switch,
Both unlatch switches 10, 20 are grounded.

In implementing the present invention, step 2
Among the determination criteria at 20, the stop state is not limited to the vehicle speed, but the shift position of the transmission of the passenger car (for example, the parking position or the neutral position), the release position of the accelerator pedal (for example, zero depression amount of the accelerator pedal). Alternatively, the determination may be made based on a combination of these.

In the embodiment of the present invention, the output of the clock 81 and / or the timer 82 is set to H from the output port of the microcomputer 80 instead of the OR gate 80b.
The signal may be output to the i-side drive element 90.

In practicing the present invention, the present invention is not limited to door lock devices for passenger cars, but may be applied to door lock devices for trucks and other various vehicles.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the microcomputer of FIG.

FIG. 3 is a timing chart showing the operation of the main constituent elements of FIG.

[Explanation of symbols]

L: door lock mechanism, M: DC motor, 10, 20: unlatch switch, 40: lock switch, 51: vehicle speed sensor, 80: microcomputer, 81: clock, 82: timer, 90: Hi side drive element, 1
00: Lo side drive element.

Continuation of the front page (72) Inventor Tetsuo Ito 1-1-1 Showa-cho, Kariya-shi, Aichi F-term in Denso Corporation (reference) 2E250 AA21 HH02 JJ46 JJ48 KK02 LL01 RR11 SS01 SS05 SS07 SS09 SS11 SS12 UU03 VV01

Claims (3)

[Claims] 1. A door lock mechanism (L) including an electric motor (M) operated by power supply from a power supply, a latch mechanism driven by the electric motor to enter a latched state or an unlatched state, and locking or unlocking the door. A switch is operated in conjunction with a lock operating means (40) operated when locking and a handle (Ho, Hi) of the door operated when the latch mechanism is brought into an unlatched state, and this switch operation is operated by operating the handle. Switch to be released by opening the switch (10,20,)
First and second switching elements (90, 100) connected in series with the motor together with the unlatch switch
Detecting means (51) for detecting a stop state of the vehicle; turning on the first switching element based on detection of the detecting means and unlocking operation of the lock operating means; Second
Control means (210, 220, 222, 231) for controlling a switching element to be turned on, wherein the door lock mechanism operates the electric motor upon power supply from the power supply to the electric motor under the control of the control means. A vehicle door lock device that sets the latch mechanism to an unlatched state in accordance with the condition. 2. The second switching element and the electric motor are connected in series between the unlatch switch and the power supply, and the unlatch switch is grounded via the first switching element. In the state where the electric motor is maintained in the non-operation state, the second
First driving means (81) for intermittently turning on a switching element for a short time, and a voltage generated between the second switching element and the electric motor and the unlatch switch is applied to the first and second switching elements. 2. The control device according to claim 1, further comprising: a second driving unit configured to turn on the second switching element for a predetermined time when the voltage is lowered by a switch operation of the unlatch switch in an on state of the switching element. 3. Vehicle door lock device. 3. The second driving means includes monitoring means for monitoring the voltage, and turning on the second switching element for the predetermined time in accordance with the monitoring of the decrease of the voltage by the monitoring means. The vehicle door lock device according to claim 2, further comprising timer means (82) for performing the operation.