JP2022139075A - Drive circuit of double lock motor - Google Patents

Abstract

To provide a drive circuit of a double lock motor capable of extending long life of a brush motor.SOLUTION: A drive circuit of a double lock motor consists of a H-bridge circuit consisting of a first half-bridge circuit 15 and a second half-bridge circuit 16 and a relay circuit 20. By using the relay circuit 20 in this way, it becomes possible to suppress occurrences of leakage current and to suppress a flow of minute currents to a door lock motor M1 or a double lock motor M2 while they are stopped. Therefore, it becomes possible to suppress wear of the brush contacts of the brush motor constituting the door lock motor M1 and the double lock motor M2, suppress occurrences of contact point failures, and extend the life of the brush motors.SELECTED DRAWING: Figure 1

Description

The present invention relates to a double lock motor drive circuit for controlling the driving of two motors for double locking and unlocking of doors.

Conventionally, it has been proposed to control the driving of two motors by a driving circuit having three half-bridge circuits (see, for example, Patent Document 1). This drive circuit has the circuit configuration shown in FIG. That is, three half-bridge circuits J1 to J3 are connected in parallel, each of which includes upper arm switches JSW1, JSW2, and JSW5 and lower arm switches JSW3, JSW4, and JSW6. One motor JM1 is connected between the intermediate potential points of the upper arm and the lower arm in two of the three half-bridge circuits J1 and J2, and two of the three half-bridge circuits J2 including the remaining one; The other motor JM2 is connected between the intermediate potential point of the upper arm and the lower arm in J3. The upper arm switches JSW1 to JSW3 of the half bridge circuits J1 to J3 are connected to the high side of the power source J4, and the lower arm switches JSW4 to JSW6 are connected to the low side of the power source J4 and the ground potential point. It is configured.

JP-A-10-313533

In the drive circuit described above, semiconductor switching elements such as MOSFETs are used as the switches JSW1 to JSW6 of the upper and lower arms. Therefore, even if the switches JSW1 to JSW6 are in the OFF state, minute currents flow through the motors JM1 and JM2 at the moment the voltage is applied. For example, when the switches JSW2 and JSW3 are turned on and the other switches JSW1 and JSW4 to JSW6 are turned off to operate the motor JM1, the same voltage is applied to the two motors JM1 and JM2 from the switch JSW2. At this time, a minute current also flows through the motor JM2 due to the leakage current of the switch JSW6.

In general, a brush motor is used in an in-vehicle motor or the like. A problem with brush motors is that the brush contacts wear during operation. For this reason, as described above, if a small amount of current flows through the motor JM2 even though the motor JM2 is not being operated, the brush contacts will wear out, causing a contact failure and causing the motor JM2 to stop operating. be done.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a double-lock motor drive circuit capable of extending the life of a brush motor.

In order to achieve the above object, the invention according to claim 1 is a double lock motor drive circuit used for driving a first motor (M1) and a second motor (M2), which is composed of semiconductor switching elements. A first half-bridge circuit (15) comprising a first switch (SW1), a second switch (SW2), a third switch (SW3) and a fourth switch (SW4), wherein the first and third switches are connected in series. A bridge circuit section (10) including an H bridge circuit in which a second half bridge circuit (16) is connected in parallel with a second switch and a fourth switch connected in series with the second motor, and is connected to the other end of the second motor. A relay switch (21) having a fixed contact (21c), a first movable contact (21a) and a second movable contact (21b), and which of the first movable contact and the second movable contact the relay switch is connected to and a relay circuit (20) having a coil (22) for controlling the The bridge circuit is connected to a high side terminal (11) connected to the high side of the first switch and the second switch and supplied with power from the power supply (2), and connected to the low side of the third switch and the fourth switch. A low side terminal (12), a first output terminal (13) connected to an intermediate potential point between the first switch and the third switch in the first half bridge circuit, and the second switch and the fourth switch in the second half bridge circuit. It has a second output terminal (14) connected to an intermediate potential point between the switch, one end of the first motor is connected to the first output terminal, and the other end of the first motor and the second output terminal are connected to the second output terminal. 2, the relay circuit has a first movable contact connected to the high side terminal and a second movable contact connected to the low side terminal.

Thus, the H-bridge circuit and the relay circuit composed of the first half-bridge circuit and the second half-bridge circuit constitute a double-lock motor drive circuit. That is, one of the conventionally used third half-bridge circuits is replaced with a relay circuit composed of a mechanical relay. By using the relay circuit in this way, it is possible to suppress the occurrence of leakage current, and to suppress the flow of minute currents to the first and second motors while they are stopped. Therefore, it is possible to suppress wear of the brush contacts of the brush motors constituting the first motor and the second motor, suppress the occurrence of contact failures, and extend the life of the brush motors.

The invention according to claim 2 has a control section (3) for controlling energization of coils in the first switch, the second switch, the third switch, the fourth switch, and the relay circuit. In this way, the double-lock motor drive circuit can be configured to include the control unit. In this case, as in the third aspect of the invention, the bridge circuit section and the control section can be provided in the same electronic control unit.

It should be noted that the reference numerals in parentheses attached to each component etc. indicate an example of the correspondence relationship between the component etc. and specific components etc. described in the embodiments described later.

1 is a diagram showing a circuit configuration of a double lock motor drive circuit according to a first embodiment of the invention; FIG. FIG. 4 is a diagram showing current paths during single lock operation; FIG. 4 is a diagram showing current paths during double lock operation; FIG. 10 is a diagram showing current supply during double lock release operation; FIG. 10 is a diagram showing current supply during a full unlock operation; 1 is a circuit configuration diagram of a conventional drive circuit; FIG.

An embodiment of the present invention will be described below with reference to the drawings. In addition, in each of the following embodiments, portions that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
A double lock motor drive circuit according to this embodiment will be described. The double lock motor drive circuit of the present embodiment is mounted on a vehicle and used for locking and unlocking (also referred to as locking/unlocking) the doors of the vehicle. In general, single locking of the door is sufficient, but double locking is preferable in order to further improve security. The double lock motor drive circuit controls this double lock of the door.

FIG. 1 is a diagram showing the circuit configuration of the double lock motor drive circuit of this embodiment. As shown in FIG. 1, the double-lock motor drive circuit 1 is configured to have a bridge circuit section 10 and a relay circuit 20 . Then, the double lock motor drive circuit 1 controls driving of the door lock motor M1 corresponding to the first motor and the double lock motor M2 corresponding to the second motor based on the power supply from the power supply 2 . The bridge circuit section 10 and the relay circuit 20 are controlled by the control section 3, and based on the control signal from the control section 3, the door lock motor M1 and the double lock motor M2 are driven.

The bridge circuit unit 10 includes a high side terminal 11 connected to the high side of the power supply 2, a low side terminal 12 connected to the low side and the ground potential point, and a first terminal connected to the door lock motor M1 and the double lock motor M2. An output terminal 13 and a second output terminal 14 are provided. The bridge circuit section 10 also includes a first switch SW1 and a second switch SW2 on the upper arm, and a third switch SW3 and a fourth switch SW4 on the lower arm.

A first half bridge circuit 15 is configured by connecting the first switch SW1 and the third switch SW3 in series, and a second half bridge circuit 16 is configured by connecting the second switch SW2 and the fourth switch SW4 in series. It is configured. An H-bridge circuit is configured by connecting the first half-bridge circuit 15 and the second half-bridge circuit 16 in parallel. A high side terminal 11 is connected between the first switch SW1 and the second switch SW2, and a low side terminal 12 is connected between the third switch SW3 and the fourth switch SW4. Also, the first output terminal 13 is connected to the intermediate potential point of the first half bridge circuit 15 , and the second output terminal 14 is connected to the intermediate potential point of the second half bridge circuit 16 . One end of the door lock motor M1 is connected to the first output terminal 13, and the other end is connected to the second output terminal . Further, one end of the double lock motor M2 is connected to the second output terminal 14, and the other end is connected to a fixed contact 21c of a relay switch 21 in the relay circuit 20, which will be described later.

The first switch SW1 to the fourth switch SW4 are composed of semiconductor switching elements, here MOSFETs, and perform on/off operations based on the application of gate voltage to the gate electrodes. The gate voltage of each of the first switch SW1 to the fourth switch SW4 is applied as one of the control signals output by the control section 3, and the first switch SW1 to the fourth switch SW4 are independently controlled. It is controlled on/off.

The relay circuit 20 is composed of a mechanical relay, and has a relay switch 21 and a coil 22. One movable contact 21a of the relay switch 21 is connected to the high side of the power supply 2, and the other movable contact 21b is connected to the low side of the power supply. It is connected to the. Then, as described above, the fixed contact 21c of the relay switch 21 is connected to one end of the double lock motor M2. The ON/OFF of the energization of the coil 22 in the relay circuit 20 is also performed based on one of the control signals output by the control section 3 . For example, the relay switch 21 is connected to the movable contact 21b when the coil 22 is not energized, and is connected to the movable contact 21a when the coil 22 is energized. The movable contact 21a corresponds to the first movable contact, and the movable contact 21b corresponds to the second movable contact.

The door lock motor M1 is for locking and unlocking the first door. The door lock motor M1 is driven based on the power supply from the power supply 2 when, for example, the user performs a locking or unlocking operation using a remote key (not shown), the first key (not shown) of the door is activated. locks or unlocks the When locking the first key, the door lock motor M1 is rotated in the normal direction by passing current in one direction, and when unlocking the first key, the motor M1 rotates in the reverse direction by passing the current in the opposite direction. be done.

The double lock motor M2 locks and unlocks the door a second time in addition to the first locking and unlocking of the door by the door lock motor M1, and is intended to enhance security. The double lock motor M2 is driven based on the power supply from the power supply 2 when, for example, the user performs a locking or unlocking operation using a remote key (not shown), the second lock (not shown) of the door is activated. locks or unlocks the The double lock motor M2 rotates in the forward direction when the second key is locked, and rotates in the reverse direction when the second key is unlocked. be done.

The control unit 3 controls driving of the door lock motor M1 and the double lock motor M2 by controlling the bridge circuit unit 10 and the relay circuit 20 . The control unit 3 is composed of a microcomputer having, for example, a CPU, ROM, RAM, I/O, and the like. Here, the control unit 3 and the bridge circuit unit 10 are shown as separate configurations, but they can be configured by one electronic control unit (ECU) such as a body ECU.

Next, the operation of the double lock motor drive circuit configured in this manner will be described.

(1) Stopping operation During idling, the control unit 3 outputs a control signal for stopping the door lock motor M1 and the double lock motor M2. Specifically, for the bridge circuit unit 10, the control unit 3 controls the gate voltage to turn off the first switch SW1, turn off the second switch SW2, turn on the third switch SW3, and turn on the fourth switch SW4. do. Further, in the relay circuit 20, the control unit 3 turns off the energization of the coil 22 so as to connect the relay switch 21 to the movable contact 21b on the GND side.

As a result, power is not supplied from the power source 2 to the door lock motor M1 and the double lock motor M2, and both ends of the door lock motor M1 and the double lock motor M2 are connected to GND. Therefore, driving of the door lock motor M1 and the double lock motor M2 is stopped.

(2) Door lock operation For example, when a user performs a door lock operation using a remote key, the control unit 3 outputs a control signal for performing a door lock operation. Here, the door lock operation is carried out in two steps of single lock operation and double lock operation. The single lock operation is an operation of driving the door lock motor M1 to lock the doors in a single lock. The double lock operation is an operation of locking the door doubly by driving the double lock motor M2 in addition to the door lock motor M1. A double lock operation is an operation that follows a single lock operation in sequence.

(2-1) Single Lock Operation During the single lock operation, the control section 3 turns off the first switch SW1, turns on the second switch SW2, turns on the third switch SW3, and turns on the fourth switch SW4 for the bridge circuit section 10. to turn off the gate voltage. Further, in the relay circuit 20, the control unit 3 energizes the coil 22 so as to connect the relay switch 21 to the movable contact 21a on the power supply side.

As a result, as shown in FIG. 2A, current is supplied from the power supply 2 through the high-side terminal 11→second switch SW2→door lock motor M1→third switch SW3, and the door lock motor M1 rotates forward. Let me. Further, since the power supply voltage is applied to both ends of the double lock motor M2, the drive is stopped.

In this way, the door lock motor M1 is driven and the double lock motor M2 is stopped, so that the first key is locked based on the drive of the door lock motor M1, and the single lock operation is performed to lock the door with a single lock. is done.

(2-2) Double Lock Operation During the double lock operation, the control section 3 turns on the first switch SW1, turns on the second switch SW2, turns off the third switch SW3, and turns off the fourth switch SW4 for the bridge circuit section 10. to turn off the gate voltage. Further, in the relay circuit 20, the control unit 3 turns off the energization of the coil 22 so as to connect the relay switch 21 to the movable contact 21b on the GND side.

As a result, as shown in FIG. 2B, current is supplied from the power supply 2 through the high-side terminal 11→the second switch SW2→the double lock motor M2→the relay circuit 20, and the double lock motor M2 rotates forward. be done. Further, the door lock motor M1 has already been driven during the single lock operation, and the door is single-locked with the first key. Therefore, when the double lock motor M2 is driven, the second key is locked, and a double lock operation is performed to double lock the door.

(3) Door Unlocking Operation For example, when the user unlocks the door using the remote key, the control section 3 outputs a control signal for unlocking the door. Here, the unlocking operation of the door is performed in two steps of the double lock releasing operation and the full unlocking operation. The double lock release operation is an operation of driving the double lock motor M2 to switch from double lock to single lock. The full unlocking operation is an operation for completely unlocking the door by driving the door lock motor M1 in addition to the double lock motor M2. The full unlocking operation is performed sequentially following the double lock releasing operation.

(3-1) Double Lock Release Operation During the double lock release operation, the controller 3 turns off the first switch SW1, turns off the second switch SW2, turns on the third switch SW3, and turns on the fourth switch SW3. The gate voltage is controlled to turn on the switch SW4. Further, in the relay circuit 20, the control unit 3 energizes the coil 22 so as to connect the relay switch 21 to the movable contact 21a on the power supply side.

As a result, as shown in FIG. 2C, current is supplied from the power source 2 through the relay circuit 20→double lock motor M2→second output terminal 14→fourth switch SW4, and the double lock motor M2 rotates in the reverse direction. be done. Further, the door lock motor M1 remains stopped because both ends are connected to the GND. Therefore, when the second key is unlocked based on the driving of the double lock motor M2, the locking of the door is switched from double locking to single locking. In this manner, a double lock release operation is performed.

(3-2) All Unlock Operation During the all unlock operation, the controller 3 turns on the first switch SW1, turns off the second switch SW2, turns off the third switch SW3, and turns off the fourth switch SW3 of the bridge circuit unit 10. The gate voltage is controlled to turn on the switch SW4. Further, in the relay circuit 20, the control unit 3 turns off the energization of the coil 22 so as to connect the relay switch 21 to the movable contact 21b on the GND side.

As a result, as shown in FIG. 2D, current is supplied from the power supply 2 through the high-side terminal 11→first switch SW1→door lock motor M1→fourth switch SW4, and the door lock motor M1 rotates in the reverse direction. be done. Further, the double lock motor M2 has already been driven at the time of the double lock release operation, and the second key is unlocked and the door is locked only once. Therefore, when the first key is also unlocked based on the driving of the door lock motor M1, the door is completely unlocked. Thus, the full unlock operation is performed.

As described above, in the present embodiment, the H bridge circuit consisting of the first half bridge circuit 15 and the second half bridge circuit 16 and the relay circuit 20 constitute the double lock motor drive circuit. That is, one of the conventionally used third half-bridge circuits is replaced with a relay circuit 20 composed of a mechanical relay. By using the relay circuit 20 in this way, it is possible to suppress the occurrence of leakage current, and to suppress the flow of minute currents to the door lock motor M1 and the double lock motor M2 while they are stopped. Therefore, it is possible to suppress wear of the brush contacts of the brush motors constituting the door lock motor M1 and the double lock motor M2, suppress the occurrence of contact failures, and extend the life of the brush motors.

(Other embodiments)
Although the present disclosure has been described based on the above embodiment, it is not limited to the embodiment, and includes various modifications and modifications within the equivalent range. In addition, various combinations and configurations, as well as other combinations and configurations, including single elements, more, or less, are within the scope and spirit of this disclosure.

For example, in the above embodiment, the bridge circuit unit 10 and the control unit 3 are arranged in the same body ECU as an example. can be

In the above embodiment, the door lock operation is divided into a single lock operation and a double lock operation, and is performed in two stages. It is also possible to lock the Similarly, the door unlocking operation is divided into a double lock releasing operation and a full unlocking operation, and is performed in two stages. You can do it.

Also, in the above embodiment, the double lock motor drive circuit drives both the door lock motor M1 and the double lock motor M2, but it can be used to drive only the door lock motor M1. For example, a double lock motor drive circuit is applied to a system that can lock and unlock the doors in order to improve security, but a system that can lock and unlock the doors is not necessarily required. Therefore, by applying the double lock motor drive circuit described in the above embodiment to a system that locks and unlocks the doors in a single layer, the versatility of the system can be enhanced. Specifically, when the double lock motor M2 is not provided, the relay circuit 20 is not attached to the circuit configuration shown in FIG. This makes it possible to improve versatility.

DESCRIPTION OF SYMBOLS 1... Double lock motor drive circuit 2... Power supply 3... Control part 10... Bridge circuit part 11... High side terminal 12... Low side terminal 13... First output terminal 14... Second output terminal 15... First half bridge circuit 16 Second half bridge circuit 20 Relay circuit 21 Relay switch 22 Coil SW1 to SW4 First to fourth switches M1 Lock motor M2 Double lock motor

Claims (3)

A double lock motor drive circuit used to drive the first motor (M1) and the second motor (M2),
A first switch (SW1), a second switch (SW2), a third switch (SW3), and a fourth switch (SW4), which are composed of semiconductor switching elements, are provided, and the first switch and the third switch are connected in series. A bridge circuit section (10) including an H bridge circuit in which a first half bridge circuit (15) by ,
a relay switch (21) having a fixed contact (21c) connected to the other end of the second motor, a first movable contact (21a) and a second movable contact (21b); and a relay circuit (20) having a coil (22) that controls which of the second movable contacts is connected,
The bridge circuit section includes a high side terminal (11) connected to the high side of the first switch and the second switch and supplied with power from a power source (2), A low side terminal (12) connected to the low side, a first output terminal (13) connected to an intermediate potential point between the first switch and the third switch in the first half bridge circuit, and the second half bridge. a second output terminal (14) connected to an intermediate potential point between the second switch and the fourth switch in the circuit; one end of the first motor is connected to the first output terminal; the other end of the first motor and one end of the second motor are connected to a second output terminal;
The relay circuit is a double lock motor drive circuit, wherein the first movable contact is connected to a high side terminal and the second movable contact is connected to a low side terminal. 2. The double according to claim 1, further comprising a control section (3) for controlling energization of said coil in said first switch, said second switch, said third switch, said fourth switch and said relay circuit. Lock motor drive circuit. 3. The double lock motor drive circuit of claim 2, wherein said bridge circuit section and said control section are provided in the same electronic control unit.

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