KR100276726B1 - Door opening prevention device by power failure - Google Patents

Abstract

The present invention relates to a door locking device of a key phone system, and a delay circuit is formed by connecting a capacitor and a resistor between an input of a driving voltage applied to the ground and a reapplied power supply, and a time constant of the capacitor and a resistor. By opening the voltage divided by the resistor as an output disapproval signal during the time that the initialization is performed by the value, the door opening prevention device by the power failure is prevented, which prevents the relay driver from performing the initialization operation due to the request of the central processing unit. .

Description

Door opening prevention device by power failure

The present invention relates to a door lock device of a key phone system, and more particularly, to a door lock device that prevents the door open when the power is temporarily cut off and resupply by a power failure.

Typically, the key phone system is powered off and then re-supplied to initialize and restart the system in a normal state. This is a common operation in the case of a system using a processor as well as a key phone system. In addition, the initialization operation is performed for all configurations constituting the system.

On the other hand, the racks constituting the claimed value of the key phone system are mounted in the rack case, the rack case is provided with a door lock device is opened or closed by an external control.

As described above, a configuration of a conventional door lock using a door relay driven by external control is as shown in FIG.

Referring to FIG. 1, a door lock device of a conventional key phone system is described. When a lock request is input from an operator of the key phone system, the CPU 110 receives the lock and outputs data for requesting the lock. . At this time, the CPU 110 is to configure the overall control of the key phone system should be capable of MMC (Man Machine Communication) with the user.

The lock request data output from the CPU 110 is provided to the relay driver 120, and the relay driver 120 receiving the lock request data outputs a control signal RL_c for driving the relay. The control signal RL_c is provided to the switching element Q1 to drive the relay RL to turn on the Q1. In this case, in FIG. 1, a transistor is used as an example of the switching element Q1, and RL_c for driving the relay uses a high level logic signal.

When Q1 is turned on by the control signal RL_c, the relay R1 is grounded and a relay driving voltage (+ 24V) is supplied. The relay RL is driven by the supply of the driving voltage, and the rack case is locked by the driving of the RL.

On the other hand, when the lock release request is input by the operator, the lock release request data is provided to the relay driver 120 by the CPU 110 through the same processing as the above lock request. The relay driver 120 which has received this outputs a low level RL_c to turn off Q1, and the relay RL stops as the supply path of the relay driving voltage is blocked due to the turn off of Q1. The lock state of is released.

However, when the power supplied to the key phone system is cut off and then supplied again due to a power failure or other reasons, the lock state of the rack case is released regardless of the user's will.

In more detail, when the power is cut off and resupplyed, the CPU 110 of the key system performs initialization, and the initialization of the relay driver 120 is performed in the initialization. That is, in the process of performing initialization, the lock release data, which is initialization data, is transmitted to the relay driver 120. As the driving of the relay RL is stopped by the lock release data, the lock of the rack case is released. Thereafter, to lock the rack case again, there must be an operator lock request.

As described above, when the power supply is cut off and then re-supplied in the conventional key phone system, there is a problem that the lock state is released regardless of the intention of the operator. .

Therefore, an object of the present invention for solving the above problems is to provide an apparatus for preventing the lock of the rack case is released according to the initialization operation when the power is supplied again.

Another object of the present invention is to provide an apparatus for preventing the unlocking according to the initialization by blocking the enable of the relay driver until the initialization of the key phone system is completed.

The present invention for achieving the object as described above constitutes a delay circuit by connecting a capacitor and a resistor between the input and the ground of the driving voltage applied because the power is cut off and then re-supplied, and the time constant of the capacitor and the resistor Implementing a door opening prevention device due to a power failure, which prevents the relay driver from performing an initialization operation due to the request of the central processing unit by outputting a voltage divided by the resistor as an output disapproval signal during a time period when initialization is performed by a value. It was.

1 is a view showing the configuration of a conventional door lock using a door relay driven by external control.

2 is a view showing the configuration of a door locking device to prevent the door opening due to power outage according to an embodiment of the present invention.

3 is a diagram illustrating an example of a delay circuit disclosed in FIG. 2 in detail;

Hereinafter, described in detail with reference to the accompanying drawings according to an embodiment of the present invention.

First, referring to FIG. 2, a configuration of a door locking device for preventing a door opening due to a power failure according to an embodiment of the present invention is as follows.

The central processing unit (CPU) 210 monitors the power supply together with the overall control of the key phone system and performs an initialization operation when the power is cut off and then supplied again. In particular, the CPU 210 initializes the relay driver 220 when the power is supplied again regardless of the prevention of the door opening due to the power failure applied in the present invention.

The relay driver 220 controls the relay RL driving by controlling the switch element Q1 by the lock request data or the unlock data provided from the CPU 210 in response to an operator's request in a state where power is normally supplied. In this case, a high level output acknowledgment signal should be applied to the output enable port (OE port) provided in the relay driver 220.

The delay circuit 230 provides an output enable signal consisting of an output acknowledgment signal or an output disapproval signal to the OE port of the relay driver 220. In particular, when the power is cut off and then supplied again, the CPU 210 may disregard the initialization data provided from the CPU 210 by providing an output disapproval signal for the time required to perform the initialization. In addition, when the initialization time elapses, an output acknowledgment signal is output so that the relay driver 220 drives the relay RL by the lock request data or the unlock data provided from the CPU 210.

Meanwhile, the time required for the initialization of the CPU 210 described above is approximately 100 ms, and the operation of driving the relay RL by the lock driver 220 or the lock release data by the relay driver 220 is the same as in the related art. Do.

3 is a diagram illustrating an example of the delay circuit 230 disclosed in FIG. 2 in detail. Referring to the configuration of the delay circuit 230 according to an embodiment of the present invention with reference to FIG. 3, the capacitor (C) and the ground between the driving voltage (+ 5V) and ground provided due to the power is cut off and re-supplied It has a configuration of an RC circuit to which a resistor R is connected. The output enable signal provided to the relay driver 220 is determined by the voltage divided by R. The value of C and R has a predetermined time constant value, and the time constant value should be set to obtain a delay time equal to or larger than the initialization time mentioned above. The reason for this is to prevent the relay driver 220 from operating while the CPU 210 performs initialization.

Hereinafter, an operation according to an exemplary embodiment of the present invention will be described in detail with reference to the above configuration.

When the operator of the key phone system requests the lock of the door provided in the rack case for storing the rack of the main unit through the MMC function, the command is provided to the CPU 210. The CPU 210 receiving the command outputs lock request data corresponding to the command, and the output lock request data is provided to the relay driver 220.

The relay driver 220 receiving the lock request data outputs a high level RL_c for driving the relay RL to lock the door. The output high level RL_c is turned on by controlling Q1 and forms a supply path of a driving voltage provided to RL by turning on Q1. As a result, the RL is driven by a driving voltage to switch the door to a locked state.

On the contrary, when the operator of the key phone system requests unlocking of the door provided in the rack case for storing the rack of the main unit through the MMC function, the command is provided to the CPU 210. The CPU 210 receiving the command outputs unlock data corresponding to the command, and the output unlock data is provided to the relay driver 220.

The relay driver 220 receiving the unlock data outputs a low level RL_c for driving the RL to release the locked door. The output low level RL_c controls Q1 to be turned off, and cuts off the supply path of the driving voltage provided to RL by turning off Q1. Therefore, the RL is not driven by the driving voltage, and the door in the locked state is switched to the unlocked state.

On the other hand, when the power is normally supplied in the locked state by the operation as described above, the door is stopped in the locked state, the CPU 210 monitors the re-supply of power.

At this time, when the power is supplied again, the supply of the driving voltage to the CPU 210, the relay driver 220, and the delay circuit 230 is restored. Due to the supply of the driving voltage, the CPU 210 performs initialization and, according to the initialization, provides initialization data requesting initialization to the relay driver 220.

However, the relay driver 220 may not perform initialization to open a door even when the initialization data is provided, as the relay driver 220 is in an enabled state.

In other words, the delay circuit 230 does not immediately output an output acknowledgment signal for enabling the relay driver 220 even when power is reapplied, and outputs the output acknowledgment signal after a delay according to an internal time constant value. do. The time constant value is determined by the values of R and C constituting the delay circuit 320. Preferably, the delay by the time constant value is required until the CPU 210 completes initialization. It should be equal to or greater than time. In addition, while the delay by the time constant value is being made, the output of the output disregard signal is cut off to enable the relay driver 220.

When the output disapproval signal is applied from the delay circuit 230, the relay driver 220 is not enabled, so even if initialization data is applied from the CPU 210, proper operation cannot be performed, and the door is locked. State can be maintained. In addition, the delay circuit 230 outputs an output acknowledgment signal at the end of the initialization, and thus the relay driver 220 which receives the delay acknowledgment signal is enabled to normally open or lock the door under the control of the operator. Will be.

As described above, the present invention can prevent the door opening due to the initialization by not enabling the relay driver until the initialization is performed even if the power is cut off and resupplyed.

Therefore, the present invention can improve the stability of the system, there is a convenience that the system operator does not have to perform a separate process for locking the door.

Claims (1)

In the device for preventing the door opening by the relay drive as the power is cut off and re-supplied in the key phone system, A central processing unit which initializes the keyphone system when the power is cut off and then supplied again; The capacitor and resistor are connected between the input of the driving voltage applied to the ground when the power is cut off and then supplied again, and the voltage divided by the resistor is output during the initialization time by the time constant value of the capacitor and the resistor. A delay circuit for outputting a non-acknowledged signal, And a relay driver to prevent the relay from being driven by the initialization data of the central processing unit when the output disapproval signal is applied, thereby maintaining a door locked state.