JP7124717B2 - electric lock controller - Google Patents

Description

The present invention relates to an electric lock controller that controls an electric lock that electrically locks and unlocks a door.

2. Description of the Related Art Electric locks that electrically lock and unlock doors are used for the purpose of improving crime prevention and operability. An electric lock controller that controls such an electric lock supplies power for operation to the electric lock to be controlled (see, for example, Patent Document 1). In such a configuration, if a short-circuit failure occurs in the power supply path of the power supply for operation, such as the wiring for connecting the electric lock controller and the electric lock, an excessive current from the electric lock controller to the electric lock, that is, an overcurrent may flow. Therefore, a conventional electric lock controller is provided with a fuse so as to be interposed in series with the power supply path, thereby realizing overcurrent protection that protects the electric lock from overcurrent.

JP 2016-000910 A

A configuration that implements overcurrent protection using a fuse (hereinafter referred to as conventional technology) has the following problems. That is, in the prior art, fuse replacement is required for recovery from an abnormality. Therefore, in the conventional technology, it is necessary to use a replaceable fuse, and it is necessary to secure a working space for fuse replacement in the housing and to mount a mechanism or the like to enable fuse replacement in the housing. As a result, it has been difficult to sufficiently reduce the size of the equipment. In addition, it is necessary to prepare a spare fuse for replacement, but if the capacity of the prepared spare fuse is not suitable for the electric lock being used, the There was a possibility that current protection would not be provided, and safety could be compromised.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electric lock controller capable of achieving overcurrent protection while reducing the size of the device and improving safety.

An electric lock controller according to claim 1 controls an electric lock that electrically locks and unlocks a door, and includes a power supply section, a control relay, a relay drive section, and a drive control section. The power supply unit generates power for operating the electric lock. The control relay has a normally open type control contact interposed in series in the power supply path from the power supply unit to the electric lock, and a control coil that closes the control contact when energized. The relay driving section energizes the control coil using the output voltage of the power supply section or a voltage that changes in the same manner as the output voltage. The drive control section controls the operation of the relay drive section.

In the above configuration, the contact of the control relay is closed (turned on) by the relay drive section energizing the control coil, whereby the electric lock controller supplies operating power to the electric lock. In the state where the operating power supply is supplied to the electric lock in this way, when a short circuit failure occurs in the power supply path of the operating power supply such as the wiring for connecting the electric lock controller and the electric lock, the above configuration Then, overcurrent protection is realized as follows.

That is, the electric lock controller configured as described above reduces the output voltage of the power supply unit toward a voltage lower than the contact holding voltage of the control relay when the output current of the power supply unit reaches a predetermined threshold current higher than the steady-state current. Equipped with lower part. If a short-circuit fault occurs, the output current of the power supply section will rise above the steady-state current. Therefore, when a short-circuit fault occurs, the output current of the power supply unit rises and reaches the threshold current, and the voltage reduction unit reduces the output voltage of the power supply unit in response to this. As the output voltage of the power supply section drops, the voltage applied to the control coil also drops. When the voltage applied to the control coil falls below the contact holding voltage (touching voltage) of the control relay, the control contact is closed (turned off). As a result, the power supply path, that is, the path through which the overcurrent caused by the short-circuit failure flows is cut off, and as a result, failure of devices such as electric locks due to the overcurrent is prevented.

However, in this case, since the power supply path is cut off, the output current of the power supply section is reduced to be sufficiently smaller than the threshold current. Therefore, the operation of lowering the output voltage by the voltage lowering section is stopped, and the output voltage of the power supply section starts to rise. As the output voltage of the power supply unit rises, the voltage applied to the control coil also rises. Then, when the voltage applied to the control coil reaches the contact holding voltage of the control relay, the control contact is turned on. As a result, the power supply path is formed again, and as a result, the overcurrent caused by the short circuit fault flows again. After that, by repeating the same operation as the operation described above, a phenomenon such as so-called chattering occurs, in which a state in which an overcurrent flows and a state in which the overcurrent is interrupted are alternately repeated.

In order to prevent such a phenomenon from occurring, the electric lock controller configured as described above detects the voltage applied to the control coil, and the detected voltage falls below a predetermined lower limit voltage lower than the contact holding voltage of the control relay. When this happens, the forced stop section is provided for forcibly stopping the energization of the relay drive section regardless of the control by the drive control section. According to such a configuration, when the control contact is turned off due to the operation of lowering the output voltage by the voltage lowering section, the forced stopping section forcibly stops the energization by the relay driving section. Therefore, according to the above configuration, even if the output voltage lowering operation by the voltage lowering unit is stopped after the control contact is turned off, the overcurrent is cut off without causing the phenomenon such as the chattering described above. state is maintained.

Thus, according to the above configuration, overcurrent protection can be realized by using a control relay having a control contact interposed in series in the power supply path without using a fuse. Therefore, in the above configuration, the problems peculiar to the configuration using a fuse (difficulty in miniaturizing the device, lower safety, etc.) do not exist, and the device can be miniaturized and the safety can be improved. can. In addition, for example, using a CPU, etc., the output current of the power supply unit is monitored, and based on the monitoring result, when the occurrence of overcurrent is detected, the control contact of the control relay is turned off. It is also conceivable to implement overcurrent protection by software relay control.

However, with such software-based relay control, overcurrent protection may not function properly due to malfunctions caused by software bugs, failure of the circuit that monitors the output current, etc. cannot be raised to On the other hand, in the above configuration, except for the drive control unit, which is assumed to include a CPU, everything can be configured by hardware. In the above configuration, the operation for overcurrent protection is performed regardless of the control by the drive control unit (without intervening the control by the drive control unit), so the reliability of the operation is Relatively high. Therefore, according to the above configuration, it is possible to further improve safety compared to overcurrent protection by software relay control.

The electric lock controller according to claim 2 has a configuration in which the output can be switched between voltage and non-voltage depending on the object to be controlled, and further includes a setting relay. The setting relay includes a normally open setting contact for switching the output while intervening in series in the power supply path from the power supply unit to the electric lock, a setting coil for closing the setting contact when energized, have In this case, the relay driving section also energizes the setting coil using the output voltage of the power supply section or a voltage that changes in the same manner as the output voltage. Further, in this case, the forced stop section detects the voltage applied to the setting coil, and when the detected voltage becomes less than a predetermined lower limit voltage lower than the contact holding voltage of the setting relay, the control by the drive control section is stopped. Instead, it forcibly stops the energization by the relay drive unit.

In the above configuration, not only the control contact but also the setting contact exist as the contact in series in the power supply path from the power source to the electric lock. Therefore, in the above configuration, in addition to overcurrent protection using a control relay, overcurrent protection using a setting relay having such a setting contact is also performed. That is, in the above configuration, the function of overcurrent protection is duplicated. The overcurrent protection operation using the setting relay is the same as the overcurrent protection operation using the control relay described above. According to such a configuration, when a short-circuit failure occurs, the two contacts (the control contact and the setting contact) intervening in series in the power supply path are turned off as the output voltage is lowered by the voltage drop section, thereby Since the path through which overcurrent flows is cut off, the safety and reliability can be further enhanced.

The electric lock controller according to claim 3 further includes a voltage adjustment unit that adjusts the voltage applied to the setting coil so that the voltage applied to the setting coil is lower than the voltage applied to the control coil. Further, in the electric lock controller according to claim 4, the contact holding voltage of the setting relay is set higher than the contact holding voltage of the control relay. According to these configurations, when a short-circuit failure occurs, the setting contact of the two contacts is turned off first as the voltage drop section reduces the output voltage, thereby realizing overcurrent protection.

When the setting contact is normally turned off, the control contact is not turned off because the output voltage of the power supply section starts to rise because the power supply path is interrupted by the setting contact being turned off. However, if the setting contact is not turned off for some reason, the control contact is turned off as the output voltage is reduced by the voltage reduction unit, thereby realizing overcurrent protection. That is, in this case, overcurrent protection is basically performed using a setting relay having a setting contact.

According to such a configuration, the following effects are obtained. That is, generally, in an electric lock controller, the control relay is opened and closed at predetermined timings for each electric lock, and the opening and closing frequency of the contacts is relatively high. On the other hand, the setting relay is opened and closed only once to switch (set) the controlled object after the device is started, for example, and the opening and closing frequency of the contact is relatively low. In general, the fewer times the contacts of a relay are opened and closed, the more reliable they are. Under such circumstances, in the electric lock controller, the reliability of the contact of the setting relay (setting contact) is much higher than the reliability of the contact of the control relay (control contact).

In the above configuration, in consideration of the circumstances peculiar to such an electric lock controller, basically, while performing overcurrent protection using the contact of the setting relay, which is considered to be highly reliable, the contact of the setting relay If any trouble occurs in the control relay, overcurrent protection is performed using the contact of the control relay, so that the safety and reliability can be further improved. In this case, the contact of the control relay will not be opened or closed for overcurrent protection as long as there is no problem with the contact of the setting relay. damage to the device is kept as low as possible, and its reliability can be favorably maintained.

In the prior art, there was a problem that it was difficult to notify the outside that the fuse had blown and the device became inoperable in the event of an abnormality, and it took a lot of time to identify the cause of the abnormality. On the other hand, the electric lock controller according to claim 5 further informs the outside that an overcurrent abnormality has occurred in which the output current of the power supply unit becomes excessive when the energization is forcibly stopped by the forced stop unit. A notification unit is provided. According to such a configuration, when an overcurrent abnormality due to a short-circuit failure or the like occurs, the abnormality is promptly notified to the outside. Therefore, according to the above configuration, it is possible to easily identify the cause of the abnormality, and to promptly take measures to eliminate the abnormality.

In general, electric locks have various specifications, and the operating current differs according to the specifications. As an electric lock controller, it is necessary to be able to perform normal control even when an electric lock of any specification is connected among electric locks of such various specifications. For this reason, when the threshold current in the voltage drop portion is a fixed value, the value is set to a relatively large current value corresponding to the electric lock with the highest operating current among electric locks of various specifications. need to leave However, in this case, if an electric lock with a relatively low operating current is connected, the start of overcurrent protection may be delayed from the appropriate timing, and there is room for improvement in terms of improving safety. There is

Therefore, in the electric lock controller according to claim 6, the voltage reduction unit is configured to be able to adjust the threshold current to an arbitrary value. According to such a configuration, the threshold current can be adjusted so that overcurrent protection is started at an appropriate timing according to the specification (operating current) of the connected electric lock. Therefore, according to the above configuration, overcurrent protection is started at an appropriate timing regardless of which specification of the electric lock is connected among the electric locks of various specifications, further improving safety. can be made

In the electric lock controller according to claim 7, the power supply section includes a switching element that performs a switching operation for generating power for operation. Further, the electric lock controller according to claim 7 further includes an energization cutoff section that cuts off the energization path of the relay driving section when the temperature of the switching element reaches or exceeds a predetermined threshold temperature. In the above configuration, when a short-circuit fault occurs and the output current of the power supply unit rises, the temperature of the switching element included in the power supply unit rises. Then, when the temperature of the switching element rises and reaches or exceeds the threshold temperature, the energization cutoff section cuts off the energization path of the relay drive section.

According to such a configuration, when a short-circuit failure occurs, even if the overcurrent protection using the relay does not function normally due to a malfunction in the operation of the voltage drop portion, the temperature rise of the switching element is prevented. Accordingly, the energization cutoff section cuts off the energization path of the relay drive section, so that the contact intervening in series with the power supply path is turned off to realize overcurrent protection. Thus, according to the above configuration, the safety can be further enhanced by multiplexing the function of overcurrent protection.

The figure which shows typically the structure of the electric lock controller which concerns on 1st Embodiment. FIG. 2 schematically shows a specific configuration of the power supply circuit according to the first embodiment; A diagram schematically showing the voltage and current supplied to the electric lock according to the first embodiment. FIG. 4 is a diagram schematically showing a specific configuration of a power supply circuit according to a second embodiment; The figure which shows typically the structure of the electric lock controller which concerns on 3rd Embodiment. The figure which shows typically the structure of the electric lock controller which concerns on 4th Embodiment. The figure which shows typically the structure of the electric lock controller which concerns on 5th Embodiment.

A plurality of embodiments will be described below with reference to the drawings. In addition, the same code|symbol is attached|subjected to the substantially same structure in each embodiment, and description is abbreviate|omitted.
(First embodiment)
A first embodiment will be described below with reference to FIGS. 1 to 3. FIG.

<Overall composition>
An electric lock controller 1 shown in FIG. 1 controls an electric lock 2 connected via terminals P1 and P2. The electric lock 2 electrically locks and unlocks a door (not shown). The electric lock 2 is for security, and is applied to a security system used for crime prevention measures in shops, houses, and the like. The electric lock controller 1 includes a power supply circuit 3 , a relay 4 , a control section 5 , a switching element 6 and a latch circuit 7 .

The power supply circuit 3 includes a power supply section 8 and a voltage reduction section 9 . The power supply unit 8 generates power for operation of the electric lock 2 and outputs it through power lines L1 and L2. The potential of the power line L2 becomes the ground (0 V), which is the reference potential of the circuit. In the following description, the power line L2 is also referred to as ground. The voltage reduction unit 9 reduces the output voltage of the power supply unit 8 toward a voltage lower than the contact holding voltage of the relay 4 when the output current of the power supply unit 8 reaches a predetermined threshold current. The threshold current is set to a predetermined value higher than the stationary current, which is the output current in the stationary state. Specifically, the threshold current is set to the upper limit value (for example, 1 A) of the steady-state current range.

The relay 4 corresponds to a control relay and has contacts 10 and a coil 11 . The contact 10 is connected between the power line L1 and the terminal P1. In other words, the contact 10 is interposed in series in the power supply path from the power supply section 8 to the electric lock 2, and corresponds to a control contact. The coil 11 controls opening and closing of the contact 10 in accordance with its energized state, and corresponds to a control coil. In this case, the contact 10 is a normally open contact. Therefore, the coil 11 is configured to turn on (close) the contact 10 when energized and turn off (open) the contact when energized.

The switching element 6 is, for example, an N-channel MOSFET, and functions as a relay driving section that energizes the coil 11 using the output voltage of the power supply section 8 . As the switching element 6, various semiconductor switching elements such as a P-channel MOSFET can be used. One terminal of the coil 11 is connected to the drain of the switching element 6, and the other terminal is connected to the power line L2. A source of the switching element 6 is connected to the power supply line L1. According to such a configuration, when the switching element 6 is turned on, the coil 11 is energized by the output voltage of the power supply section 8, and when the switching element 6 is turned off, the energization of the coil 11 is stopped.

A gate of the switching element 6 is supplied with a drive signal output from the control unit 5 , thereby controlling the operation (on/off) of the switching element 6 . The control unit 5 is mainly composed of a CPU, and controls the operation of the switching element 6 based on commands given from a higher-level control device provided outside the electric lock controller 1 . Thus, the control section 5 functions as a drive control section that controls the operation of the switching element 6 corresponding to the relay drive section.

In this case, the control unit 5 controls the operation of the switching element 6 so that the power for operation is supplied to the electric lock 2 at a predetermined timing. For example, if the electric lock 2 is designed to be unlocked by supplying power for operation, the control unit 5 receives an unlocking instruction from the user (for example, an operation of touching an IC card to a card reader). is turned on, the switching element 6 is turned on. As a result, the contact 10 of the relay 4 is turned on and the electric power is supplied to the electric lock 2 to unlock it.

Latch circuit 7 detects the voltage applied to coil 11 based on the drain voltage of switching element 6 . The latch circuit 7 can also detect the voltage applied to the coil 11 based on the voltage of the power supply line L1 (the source voltage of the switching element 6). Further, when the detected voltage thus detected becomes less than the lower limit voltage, the latch circuit 7 forces the gate voltage of the switching element 6 to the off level regardless of the level of the drive signal output from the control section 5. turn into

As a result, the switching element 6 is fixed off regardless of the drive control by the control unit 5, and the coil 11 cannot be energized. The lower limit voltage described above is set to a voltage lower than the contact holding voltage (moving voltage) of the relay 4, for example. In this manner, the latch circuit 7 functions as a forced stop section that forcibly stops the energization of the switching element 6 regardless of control by the control section 5 when the detected voltage becomes less than the lower limit voltage.

Further, when the gate voltage of the switching element 6 is forcibly changed to the off-level as described above, the latch circuit 7 notifies the control section 5 of information to that effect. Upon receipt of the above notification from the latch circuit 7, the control unit 5 determines that an overcurrent abnormality has occurred in which the output current of the power supply unit 8 becomes excessive, and notifies the higher-level control device to that effect. In response to this, the host control device notifies the user of the occurrence of the overcurrent abnormality by means of display, voice, or the like. Thus, the control unit 5 has a function as a notification unit that notifies the outside that an overcurrent abnormality has occurred. Further, in this case, when the overcurrent abnormality is resolved, the fact is transmitted to the latch circuit 7 via the higher control device and the control section 5 . In response to this, the latch circuit 7 cancels the operation for forcibly fixing the switching element 6 off.

<Specific Configuration of Power Supply Circuit>
As a specific configuration of the power supply circuit 3, for example, a configuration as shown in FIG. 2 can be adopted. As shown in FIG. 2, the power supply circuit 3 is configured as a step-down switching regulator that steps down and stabilizes an input voltage Vin that is externally applied via an input node Ni and outputs it via an output node No. . A steady-state value of the output voltage Vo output from the output node No is, for example, +24V.

The power supply circuit 3 includes capacitors 21 and 22, a switching element 23 such as an N-channel MOSFET, a coil 24, a diode 25, resistors 26 to 28, a power control unit 29, and the like. A capacitor 21 is for smoothing the input voltage Vin and is connected between the input node Ni and the ground. A capacitor 22 is for smoothing the output voltage Vout and is connected between the output node No and the ground.

The switching element 23 is, for example, an N-channel MOSFET, and performs a switching operation to generate operating power. Various semiconductor switching elements such as a P-channel MOSFET can be used as the switching element 23 . The source of switching element 23 is connected to input node Ni, and its drain is connected to output node No via coil 24 and resistor 26 . The gate of the switching element 23 is supplied with a driving signal output from the power supply control unit 29 , thereby controlling the driving (switching operation) of the switching element 23 . The diode 25 has its cathode connected to the drain of the switching element 23 and its anode connected to the ground.

A series circuit of resistors 27 and 28 is connected between the output node No and ground. Resistors 27 and 28 form a voltage dividing circuit that divides output voltage Vo, and the divided voltage output from node N1, which is their interconnection node, is applied to power supply control section 29. FIG. The power control unit 29 detects the output voltage Vout based on the divided voltage, and controls the switching element so that the output voltage Vout matches a desired target voltage (for example, a steady-state value of 24 V) based on the detected value. 23 is controlled. In this manner, in the above configuration, the power supply section 8 is configured by each configuration except for the resistor 26 .

A resistor 26 is a sense resistor for detecting the output current of the power supply circuit 3 (power supply section 8 ), and each terminal voltage thereof is given to the power supply control section 29 . The power control unit 29 detects the output current based on each terminal voltage of the resistor 26 . When the power control unit 29 detects that the output current has reached a threshold current (for example, 1 A) higher than the steady-state current based on the detected value, the power control unit 29 stops driving the switching element 23 and reduces the on-duty in switching. , etc. to lower the output voltage Vout. Thus, in the above configuration, the voltage drop section 9 is configured by the resistor 26 and the power control section 29 .

Next, the operation of the above configuration will be described.
In the above configuration, when the switching element 6 is turned on to energize the coil 11, the contact 10 of the relay 4 is turned on, whereby the electric lock controller 1 supplies the electric lock 2 with operating power. . In the state where the operating power supply is supplied to the electric lock 2 in this way, a short circuit failure (for example, wiring short circuit) occurs in the power supply path of the operating power supply, such as the wiring for connecting the electric lock controller 1 and the electric lock 2 . etc.) occurs, in the above configuration, overcurrent protection is implemented as follows.

The operation of such overcurrent protection will be described below with reference to FIG. 3 indicates the voltage between the terminals P1 and P2, that is, the voltage supplied to the electric lock 2. As shown in FIG. 3 indicates the current flowing between the terminals P1 and P2, that is, the current supplied to the electric lock 2. As shown in FIG. If the contact 10 of the relay 4 is on, the voltage and current supplied to the electric lock 2 are substantially the same as the output voltage and current of the power supply section 8, respectively. Therefore, in the following description, when it is not necessary to distinguish between the voltage supplied to the electric lock 2 and the output voltage of the power supply unit 8, they are collectively referred to as the output voltage of the power supply unit 8, and When it is not necessary to distinguish between the supplied current and the output current of the power supply section 8, they are collectively referred to as the output current of the power supply section 8. FIG.

When a short-circuit fault occurs, the output current of the power supply unit 8 rises beyond the upper limit of the steady-state current range. Therefore, when a short-circuit failure occurs, the output current of the power supply unit 8 rises and reaches the threshold current, and the voltage reduction unit 9 reduces the output voltage of the power supply unit 8 in response to this. As the output voltage of the power supply section 8 decreases, the voltage applied to the coil 11 also decreases. Then, when the voltage applied to the coil 11 falls below the contact holding voltage (moving voltage) of the relay 4, the contact 10 is turned off (relay contact OFF). As a result, the power supply path, that is, the path through which the overcurrent caused by the short-circuit fault flows is cut off, so that both the voltage and the current supplied to the electric lock 2 become zero. Failure of equipment such as the lock 2 is prevented.

The timing of such relay contact OFF, that is, the timing of starting overcurrent protection, can be set to any timing according to the specifications of the power supply circuit 3 (threshold current setting value, etc.) and the specifications of the relay 4 (operating voltage, etc.). can do. In this embodiment, the start timing of the overcurrent protection is set at the time when the output current of the power supply unit 8 becomes twice the upper limit value of the stationary current (for example, 2A).

However, in this case, since the power supply path is cut off, the output current of the power supply unit 8 is reduced to be sufficiently smaller than the threshold current. Therefore, the operation of lowering the output voltage by the voltage lowering section 9 is stopped, and the output voltage of the power supply section 8 turns to rise. As the output voltage of the power supply unit 8 rises, the voltage applied to the coil 11 also rises. Then, when the voltage applied to the coil 11 reaches the contact holding voltage of the relay 4, the contact 10 is turned on. As a result, the power supply path is formed again, and as a result, the overcurrent caused by the short circuit fault flows again. After that, by repeating the same operation as the operation described above, a phenomenon such as so-called chattering occurs, in which a state in which an overcurrent flows and a state in which the overcurrent is interrupted are alternately repeated.

However, in the electric lock controller 1 configured as described above, when the contact 10 is turned off due to the operation of lowering the output voltage by the voltage lowering section 9, the latch circuit 7 fixes the switching element 6 to the off state to force the coil 11 to be energized. stop automatically. Therefore, according to the above configuration, even if the output voltage lowering operation by the voltage lowering unit 9 is stopped after the contact 10 is turned off, the overcurrent is cut off without causing the phenomenon such as the chattering described above. state is maintained.

According to this embodiment described above, the following effects are obtained.
According to the electric lock controller 1 of this embodiment, overcurrent protection can be realized by using the relay 4 having the contact 10 interposed in series with the power supply path without using a fuse unlike the conventional technology. Therefore, in the above configuration, the problems peculiar to the configuration using a fuse (difficulty in miniaturizing the device, lower safety, etc.) do not exist, and the device can be miniaturized and the safety can be improved. can.

The safety referred to here is safety due to the fact that the capacity of the spare fuse described in the prior art is not the capacity applied to the electric lock being used (the spare becomes incompatible). In this embodiment, since it is a configuration that realizes overcurrent protection using the reusable relay 4, there is no need for a spare in the first place, and there is no risk that the spare will be unsuitable. can improve sexuality.

For example, the output current of the power supply unit 8 is monitored using the control unit 5 mainly composed of a CPU. It is also conceivable to implement overcurrent protection by software relay control, such as off control of the contact 10 .

However, with such software-based relay control, overcurrent protection may not function properly due to malfunctions caused by software bugs, failure of the circuit that monitors the output current, etc. cannot be raised to On the other hand, in the above configuration, everything except for the control unit 5 can be configured by hardware. In the above configuration, the operation for overcurrent protection is performed regardless of the control by the control unit 5 (without intervening the control by the control unit 5). Relatively high. Therefore, according to this embodiment, the safety can be further improved compared to overcurrent protection by software relay control.

In the prior art, there was a problem that it was difficult to notify the outside that the fuse had blown and the device became inoperable in the event of an abnormality, and it took a lot of time to identify the cause of the abnormality. On the other hand, in the electric lock controller 1 of the present embodiment, when an overcurrent abnormality due to a short-circuit failure or the like occurs, the control unit 5 that receives the notification from the latch circuit 7 detects that an overcurrent abnormality has occurred. , and promptly notify the outside. Therefore, according to the present embodiment, when an overcurrent abnormality occurs, it is possible to easily identify the cause of the abnormality and to promptly take measures to eliminate the abnormality.

In the above configuration, since the relay 4 is a mechanical relay, the opening/closing operation of the contact 10 is slower than the fluctuation of the current such as the output current of the power supply section 8 . Therefore, in the above configuration, there is a high possibility that chattering will occur as the operation of the relay 4 when a short-circuit failure occurs. Therefore, in this embodiment, the latch circuit 7 that operates as described above is provided to prevent chattering.

Furthermore, in this case, if the voltage reduction unit 9 reduces the output voltage of the power supply unit 8 toward a voltage sufficiently lower than the contact holding voltage of the relay 4 when the output current of the power supply unit 8 reaches the threshold current, The effect of preventing chattering can be further enhanced. This is because, in the event of a short-circuit fault, even if the output current of the power supply unit 8 becomes slightly less than the threshold current and the output voltage reduction operation of the voltage reduction unit 9 is stopped, the output voltage of the power supply unit 8 is lowered to a voltage sufficiently lower than the contact holding voltage of the relay 4, it does not immediately rise to reach the contact holding voltage. Therefore, according to the above configuration, when a short-circuit failure occurs, even if the output current of the power supply unit 8 slightly fluctuates around the threshold current, it is possible to reliably prevent the occurrence of chattering as the operation of the relay 4. be able to.

(Second embodiment)
A second embodiment in which the specific configuration of the power supply circuit and the like are changed from the first embodiment will be described below with reference to FIG.
As shown in FIG. 4, the power supply circuit 31 of this embodiment differs from the power supply circuit 3 of the first embodiment shown in FIG. . Variable resistor 32, like resistor 26, is a sense resistor. In this case, the variable resistor 32 and the power control unit 29 constitute the voltage drop unit 9 .

In the power supply circuit 31, when the resistance value of the variable resistor 32, which is a sense resistor, is changed, the voltage generated between the terminals of the variable resistor 32 due to the output current of the power supply unit 8 flowing through the variable resistor 32, that is, the output current. Detected value changes. Therefore, when the resistance value of the variable resistor 32 is changed, the threshold current in the voltage drop section 9 is changed. Therefore, the voltage reduction unit 9 in this case has a configuration capable of adjusting the threshold current to an arbitrary value.

The control unit 5 adjusts the resistance value of the variable resistor 32 and thus adjusts the value of the threshold current. When the operation of the electric lock controller 1 is started, the specifications of the electric lock 2 to be connected according to the user's operation, etc. are notified to the control unit 5 and registered. In response to this, the control unit 5 adjusts the resistance value of the variable resistor 32, and thus the value of the threshold current, so that overcurrent protection is started at an appropriate timing according to the specifications of the connected electric lock 2. It is designed to

According to this embodiment described above, the following effects are obtained.
In general, the electric lock 2 has various specifications, and the operating current differs according to the specifications. As the electric lock controller 1, it is necessary to be able to normally control the electric lock 2 of any specification among the electric locks 2 of such various specifications. For this reason, when the threshold current in the voltage reduction unit 9 is a fixed value, the value is set to a relatively large current value corresponding to the electric lock 2 with the highest operating current among the electric locks 2 of various specifications. Must be set. However, in this case, if an electric lock 2 with a relatively low operating current is connected, the start of overcurrent protection may be delayed from the appropriate timing, and improvement in terms of safety cannot be improved. There is room.

Therefore, in this embodiment, the voltage reduction unit 9 is configured to be able to adjust the threshold current to an arbitrary value. According to such a configuration, the threshold current can be adjusted according to the specifications (operating current) of the electric lock 2 to be connected so that overcurrent protection is started at an appropriate timing. Therefore, according to the present embodiment, even when the electric lock 2 of any specification is connected among the electric locks 2 of various specifications, the overcurrent protection is started at an appropriate timing, and safety is ensured. It can be improved further.

(Third embodiment)
A third embodiment will be described below with reference to FIG.
The electric lock controller 41 of this embodiment shown in FIG. 5 differs from the electric lock controller 1 of the first embodiment shown in FIG. 1 in that a thermistor 42 is added. The thermistor 42 is a PTC thermistor whose resistance sharply rises when the ambient temperature exceeds a predetermined threshold temperature. The thermistor 42 is inserted in series in the path through which the coil 11 is energized by the switching element 6 . Specifically, the thermistor 42 is connected between the source of the switching element 6 and the power supply line L1.

Although not shown, the thermistor 42 is arranged near the switching element 23 of the power supply circuit 3 . According to the above configuration, when the switching element 23 generates heat and the ambient temperature exceeds the threshold temperature, the resistance value of the thermistor 42 rises sharply, and the power supply path from the power supply line L1 to the source of the switching element 6 is cut off. As a result, the energization path to the coil 11 by the switching element 6 is cut off. In this way, the thermistor 42 cuts off the path of current flow to the coil 11 when the temperature of the switching element 23 becomes equal to or higher than the threshold temperature, and corresponds to a power cutoff section.

According to this embodiment described above, the following effects are obtained.
In the electric lock controller 41 of the present embodiment, when a short circuit fault occurs and the output current of the power supply circuit 3 (power supply unit 8) increases, the temperature of the switching element 23 included in the power supply circuit 3 increases. Then, when the temperature of the switching element 23 rises to the threshold temperature or higher, the resistance value of the thermistor 42 rises sharply and the path of current flow to the coil 11 is cut off.

According to such a configuration, when a short-circuit failure occurs, even if the overcurrent protection using the relay 4 does not function normally due to a malfunction in the operation of the voltage drop unit 9, the switching element 23 As the temperature rises, the resistance value of the thermistor 42 rises sharply and the path of current to the coil 11 is cut off, so the contact 10 of the relay 4 intervening in series with the power supply path is turned off to realize overcurrent protection. be done. As described above, according to the present embodiment, since the overcurrent protection function is multiplexed, the safety can be further enhanced.

(Fourth embodiment)
A fourth embodiment will be described below with reference to FIG.
The electric lock controller 51 of this embodiment shown in FIG. 6 differs from the electric lock controller 41 of the third embodiment shown in FIG. 5 in that the connecting position of the thermistor 42 is changed. In this case as well, the thermistor 42 is inserted in series in the path through which the coil 11 is energized by the switching element 6 . However, in this case, the thermistor 42 is connected between the drain of the switching element 6 and the coil 11 of the relay 4 .

Although not shown, the thermistor 42 is arranged near the switching element 23 of the power supply circuit 3 . According to the above configuration, the thermistor 42 thus cuts off the path of energization to the coil 11 when the temperature of the switching element 23 becomes equal to or higher than the threshold temperature, and corresponds to an energization cutoff section.

According to the configuration of the present embodiment described above, similarly to the configuration of the third embodiment, when the switching element 23 generates heat and the ambient temperature exceeds the threshold temperature, the resistance value of the thermistor 42 rises sharply, and the switching element 6 , the path of energization to the coil 11 is interrupted. Therefore, this embodiment also provides the same effects as the third embodiment.

(Fifth embodiment)
A fifth embodiment will be described below with reference to FIG.
The electric lock controller 61 of the present embodiment shown in FIG. 7 includes the electric lock 2, which is a device controlled by a voltage contact output, and a device controlled by a non-voltage contact output, such as an automatic door (not shown) (hereinafter referred to as an automatic door, etc.). ) can be selectively controlled. In this case, the automatic door or the like corresponds to a device to be controlled other than the electric lock 2 .

When the electric lock controller 61 controls the electric lock 2, the electric lock controller 61 switches between a state in which the supply of power for operation is executed and a state in which the supply of power for operation is stopped according to the opening and closing of the contact 10 of the relay 4. need to switch. Further, when an automatic door or the like is to be controlled, the electric lock controller 61 switches between a state in which the terminals P1 and P2 are short-circuited and a state in which the terminals P1 and P2 are opened according to the opening and closing of the contact 10 of the relay 4. , must be switched. In other words, the electric lock controller 61 needs to be configured so that its output can be switched between voltage and non-voltage depending on the object to be controlled.

In order to realize such a function, the electric lock controller 61 has a relay 62, a switching element 63 and a resistor 64 added to the electric lock controller 1 of the first embodiment shown in FIG. 5 and latch circuit 7, a control unit 65 and a latch circuit 66 are provided. The relay 62 is for switching the output of the electric lock controller 61, that is, for switching (setting) a device to be controlled by the electric lock controller 61, and corresponds to a setting relay. Relay 62 has contacts 67 , 68 and coil 69 .

A first switching terminal A of the contact 67 is connected to the power line L1, and a first switching terminal A of the contact 68 is connected to the power line L2. A second switching terminal B of the contact 67 is connected to a second switching terminal B of the contact 68 . A common terminal of contact 67 is connected to terminal P1 via contact 10 of relay 4 . A common terminal of contact 68 is connected to terminal P2. In this case, the contacts 67 and 68 are interposed in series in the power supply path from the power supply section 8 to the electric lock 2 and correspond to setting contacts. The coil 69 controls opening and closing of the contacts 67 and 68 according to the energized state thereof, and corresponds to a setting coil.

When the coil 69 is energized, both the contacts 67 and 68 are switched to the first switching terminal A side. Also, the coil 69 switches both the contacts 67 and 68 to the second switching terminal B side when the energization is stopped. In this case, the state in which the contacts 67 and 68 are switched to the first switching terminal A side corresponds to the state in which the contacts are turned on (closed). In this case, the state in which the contacts 67 and 68 are switched to the second switching terminal B side corresponds to the state in which the contacts are turned off (opened). For this reason, the contacts 67 and 68 can be said to be normally open contacts.

The switching element 63 is, for example, an N-channel MOSFET, and functions as a relay driving section that energizes the coil 69 using the output voltage of the power supply section 8 . One terminal of the coil 69 is connected to the drain of the switching element 63, and the other terminal is connected to the power line L2. The source of the switching element 63 is connected to the power supply line L1 via the resistor 64. As shown in FIG. According to such a configuration, when the switching element 63 is turned on, the coil 69 is energized with a voltage lower than the output voltage of the power supply unit 8 by the voltage drop due to the resistor 64, and when the switching element 63 is turned off. The energization of the coil 69 is stopped.

A gate of the switching element 63 is supplied with a driving signal output from the control unit 65, thereby controlling the operation (on/off) of the switching element 63. FIG. The control unit 65 controls operations of the switching elements 6 and 63 based on commands given from a higher-level control device provided outside the electric lock controller 61 . In this case, the control section 65 controls the operation of the switching element 6 in the same manner as the control section 5 .

Also, in this case, the control unit 65 controls the operation of the switching element 63 as follows. That is, the control unit 65 turns on the switching element 63 when a command is given to the effect that the electric lock 2 is to be controlled. As a result, the contacts 67 and 68 of the relay 62 are both switched to the first switching terminal A side, and the electric lock 2 is supplied with operating power according to the opening/closing of the contact 10 of the relay 4. , and a state in which the supply of power for operation is stopped. Further, the control unit 65 turns off the switching element 63 when a command is given to the effect that an automatic door or the like is to be controlled. As a result, the contacts 67 and 68 of the relay 62 are both switched to the second switching terminal B side, and according to the opening and closing of the contact 10 of the relay 4, the terminals P1 and P2 are short-circuited, and the terminals P1 and P2 are closed. can be switched between a state in which the

Like the latch circuit 7 , the latch circuit 66 can fix the switching element 6 off regardless of the drive control by the controller 65 . Also, the latch circuit 66 detects the voltage applied to the coil 69 based on the drain voltage of the switching element 63 . Note that the latch circuit 66 can also detect the voltage applied to the coil 69 based on the source voltage of the switching element 63 . Further, when the detected voltage thus detected becomes less than the lower limit voltage, the latch circuit 66 forces the gate voltage of the switching element 63 to the off level regardless of the level of the drive signal output from the control section 65. turn into

As a result, the switching element 63 is fixed off regardless of the drive control by the control section 65, and the coil 69 cannot be energized. The above-described lower limit voltage is set to a voltage lower than the contact holding voltage (moving voltage) of the relay 62, for example. In this case, the contact holding voltages of the relays 4 and 62 are approximately the same voltage. In this manner, the latch circuit 66 functions as a forced stop section that forcibly stops the energization of the switching element 63 regardless of the control by the control section 65 when the detected voltage becomes less than the lower limit voltage.

In the above configuration, the voltage applied to the coil 11 of the relay 4 is approximately the same as the output voltage of the power supply unit 8, whereas the voltage applied to the coil 69 of the relay 62 is similar to the voltage applied to the power supply unit 8. is lower than the output voltage of the resistor 64 by the voltage drop of the resistor 64 . Therefore, the resistor 64 functions as a voltage adjuster that adjusts the voltage applied to the coil 69 of the relay 62 to be lower than the voltage applied to the coil 11 of the relay 4 .

According to this embodiment described above, the following effects are obtained.
The electric lock output of the electric lock controller 61 of the present embodiment can be controlled depending on the object to be controlled. When a device is to be controlled), a relay 4 corresponding to a control relay and a relay 62 corresponding to a setting relay for switching the device to be controlled are provided. ing. In the above configuration, not only the contact 10 of the relay 4 but also the contacts 67 and 68 of the relay 62 exist as contacts that are serially interposed in the power supply path from the power supply unit 8 to the electric lock 2 .

Therefore, in the electric lock controller 61 of this embodiment, in addition to overcurrent protection using the relay 4, overcurrent protection using the relay 62 having such contacts 67 and 68 is also performed. That is, in the electric lock controller 61 of this embodiment, the overcurrent protection function is duplicated. The overcurrent protection operation using the relay 62 is the same as the overcurrent protection operation using the relay 4 described in each of the above embodiments. According to such a configuration, when a short-circuit failure occurs, the contacts 10, 67, 68 intervening in series in the power supply path are turned off as the output voltage is lowered by the voltage drop section 9, thereby causing an overcurrent to flow. is cut off, the safety and reliability can be further enhanced.

In the electric lock controller 61 of the present embodiment, since the resistor 64 is inserted between the source of the switching element 63 and the power line L1, the coil of the relay 62 is The voltage applied to 69 is adjusted to be low. According to such a configuration, when a short-circuit failure occurs, out of the contacts 10 of the relay 4 and the contacts 67 and 68 of the relay 62, the contacts 67 and 68 of the relay 62 fall as the voltage drop portion 9 reduces the output voltage. is turned off first (switched to the second switching terminal B side), thereby realizing overcurrent protection.

When the contacts 67 and 68 of the relay 62 are normally turned off, the power supply path from the power supply unit 8 to the electric lock 2 is cut off by turning off the contacts 67 and 68, so that the output voltage of the power supply unit 8 begins to rise. Therefore, the contact 10 of the relay 4 is never turned off. However, if the contacts 67 and 68 of the relay 62 are not turned off for some reason, the contact 10 of the relay 4 is turned off as the output voltage is lowered by the voltage drop unit 9, thereby realizing overcurrent protection. That is, in this case, basically, overcurrent protection using the relay 62 having contacts 67 and 68 is performed.

By doing so, the following effects can be obtained. That is, generally, in the electric lock controller 1, the relay 4, which is a control relay, is opened and closed at predetermined timings for each electric lock 2, and the opening and closing frequency of the contact 10 is relatively high. On the other hand, the relay 62, which is a setting relay, is opened and closed only once to switch (set) the controlled object after the device is started, for example. is relatively low. In general, the fewer times the contacts of a relay are opened and closed, the more reliable they are. Due to these circumstances, in the electric lock controller 61, the reliability of the contacts 67 and 68 of the relay 62, which is a setting relay, is much higher than the reliability of the contact 10 of the relay 4, which is a control relay. there is

In this embodiment, in consideration of such circumstances specific to the electric lock controller 61, overcurrent protection is provided using the contacts 67 and 68 of the relay 62, which is a setting relay that is considered to be highly reliable. In addition, if some trouble occurs in the relay 62, overcurrent protection is performed using the contact 10 of the relay 4, which is a control relay, so that the safety and reliability are further improved. be able to. In this case, the contact 10 of the relay 4, which is a control relay, is not opened or closed for overcurrent protection unless the relay 62 has a problem. Damage to the contacts 10 due to factors other than opening/closing operations (execution and stop of power supply, etc.) can be suppressed as low as possible, and the reliability thereof can be maintained satisfactorily.

(Other embodiments)
The present invention is not limited to the embodiments described above and illustrated in the drawings, and can be arbitrarily modified, combined, or expanded without departing from the scope of the invention.
The numerical values and the like shown in the above embodiment are examples, and are not limited to them.
The present invention can be applied not only to the electric lock controller that controls the electric lock 2 for security, but also to electric lock controllers that control electric locks in general.

A specific configuration of the power supply circuit including the power supply unit 8 and the voltage reduction unit 9 can be appropriately changed according to the specifications of the electric lock controller. Therefore, the power supply circuit is not limited to the step-down type switching regulator shown in FIG. Regardless of which type of power supply circuit is employed, it is possible to provide a configuration having the same functions as the power supply section 8 and the voltage drop section 9 based on the concept described in each of the above embodiments.

In each of the above embodiments, the coil 11 of the relay 4 is energized using the output voltage of the power supply unit 8. A configuration in which the coil 11 is energized may be used. Even with such a configuration, as the output voltage of the power supply section 8 drops, the voltage applied to the coil 11 also drops, so that the same effects and effects as those of the above-described embodiments can be obtained.

In the electric lock controller 61 of the fifth embodiment, the resistor 64 functioning as a voltage regulator may be omitted. However, in this case, the contact holding voltage of the setting relay 62 should be set higher than the contact holding voltage of the control relay 4 . In this way, as in the fifth embodiment, basically overcurrent protection using the relay 62 is performed, so that the same actions and effects as in the fifth embodiment can be obtained.

DESCRIPTION OF SYMBOLS 1, 41, 51, 61... Electric lock controller, 2... Electric lock, 4... Relay, 5... Control part, 6... Switching element, 7... Latch circuit, 8... Power supply part, 9... Voltage drop part, 10... Contact , 11... Coil, 23... Switching element, 42... Thermistor, 62... Relay, 63... Switching element, 64... Resistor, 65... Control unit, 66... Latch circuit, 67, 68... Contact, 69... Coil.

Claims (7)

An electric lock controller that controls an electric lock that electrically locks and unlocks a door,
a power supply unit that generates a power supply for operating the electric lock;
A control relay having a normally open control contact interposed in series in a power supply path from the power supply unit to the electric lock and a control coil that closes the control contact when energized;
a relay driving unit that energizes the control coil using the output voltage of the power supply unit or a voltage that changes in the same manner as the output voltage;
a drive control unit that controls the operation of the relay drive unit;
a voltage reduction unit that reduces the output voltage of the power supply unit toward a voltage lower than the contact holding voltage of the control relay when the output current of the power supply unit reaches a predetermined threshold current higher than the steady-state current;
The voltage applied to the control coil is detected, and when the detected voltage becomes less than a predetermined lower limit voltage lower than the contact holding voltage of the control relay, the relay drive unit is operated regardless of control by the drive control unit. a forced stop unit for forcibly stopping energization;
an electric lock controller. The configuration is such that the output can be switched between voltage and non-voltage depending on the object to be controlled,
Further, a normally open setting contact for switching the output and a setting coil for closing the setting contact when energized are interposed in series in the power supply path from the power supply unit to the electric lock. Equipped with setting relays,
The relay drive unit energizes the setting coil using the output voltage of the power supply unit or a voltage that changes in the same manner as the output voltage,
The forced stop unit detects the voltage applied to the setting coil, and when the detected voltage becomes less than a predetermined lower limit voltage lower than the contact holding voltage of the setting relay, regardless of the control by the drive control unit. 2. The electric lock controller according to claim 1, wherein energization by said relay driving unit is forcibly stopped. 3. The electric lock controller according to claim 2, further comprising a voltage adjusting section that adjusts the voltage applied to the setting coil so as to be lower than the voltage applied to the control coil. 4. An electric lock controller according to claim 2 or 3, wherein the contact holding voltage of said setting relay is set higher than the contact holding voltage of said control relay. 5. The apparatus according to any one of claims 1 to 4, further comprising a notification unit that notifies the outside that an overcurrent abnormality has occurred in which the output current of the power supply unit becomes excessive when the energization is forcibly stopped by the forced stop unit. or the electric lock controller according to claim 1. The electric lock controller according to any one of claims 1 to 5, wherein the voltage reduction unit is configured to be able to adjust the threshold current to an arbitrary value. The power supply unit includes a switching element that performs a switching operation to generate the operating power supply,
The electric lock controller according to any one of claims 1 to 6, further comprising an energization cutoff section that cuts off a path of energization by the relay driving section when the temperature of the switching element reaches or exceeds a predetermined threshold temperature.

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