JPS5834877B2 - Anti-theft alarm device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-theft alarm device, and particularly to an anti-theft alarm device constructed using a semiconductor device such as an IC circuit, electronic components, and the like.

Conventionally, there have been various devices that install electrical contacts with a mechanical structure in places where there is a risk of illegal entry from the outside of a building, such as doors and windows, and that detect the opening or closing of these contacts and issue an alarm. If someone enters the building, the alarm will go off without resetting the selector switch inside the building, causing noise pollution when unattended, and making it impossible to distinguish between caution and alarm signals. However, there were drawbacks such as the need for multiple selection switches.

The present invention was made in order to solve the above-mentioned drawbacks, and it is an object of the present invention to provide an easy-to-operate anti-theft alarm device.

In the present invention, when a family member goes out, he or she sets the select switch before going outside, but even if the door is opened at this time, the warning signal and alarm are not emitted, and when the family member returns home,
Even if the door is opened, the alarm does not sound immediately; instead, a caution signal is issued first, and the alarm sounds after a predetermined period of time. During this time, the select switch can be reset, and places such as windows where normal holes cannot go in or out are illegally opened. The system is designed to set off an alarm immediately if an intruder is opened, and if a door or window that has been opened is closed again, the caution signal and alarm can be automatically stopped after approximately 2 minutes have elapsed. .

Furthermore, it is an object of the present invention to provide a miniaturized alarm device using a semiconductor device such as an IC that can perform these operations with only one select switch.

Examples will be described below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the theft prevention alarm device according to the present invention.

In Fig. 1, E is a battery power supply, and ■ is a signal generating device, which generates, for example, the sound of a small bird.

[F] is an alarm device, such as a bell or buzzer, which can notify of an emergency.

Ss is a select inch, which is a switch for a householder to set or reset the alarm device, and has a movable contact piece 5, one end of which is grounded, a reset contact 6, and a set contact piece 7.

Sd is a switch that opens and closes when the door opens and closes, Sw is a switch that opens and closes when the window opens and closes, TR1 to TR8
are switching transistors, R1 to R1□ are resistors, C1 to c4 are capacitors, and D1 to D3 are reverse current blocking diodes.

NAND is a NAND circuit, and when a high level signal is input to both of its 2 input terminals, a low level signal is output.
When a low level signal is input to both of these two input terminals, a high level signal is input to one input terminal, and a low level signal is input to the other, a high level signal is output from both.

N0TI, N0T2. N0Ts is a NOT circuit that outputs a low level signal when a high level signal is input, and conversely outputs a high level signal when a low level signal is input.These NAND circuits and NOT circuits are IC It is a highly compact element.

The operation of this embodiment is as follows: (1) When the select switch is turned to the reset state, (ii) When the select switch is turned to the set state and the door is opened, the 010 select switch is turned to the set state. The operation of the present invention will be explained in detail for each case: when the windows are opened when the windows are closed, and when the 4ψ select switch is switched from the set state to the reset state.

(i) When the select switch is in the reset state.

When the movable contact 5 of the select switch is in the position shown, ie in the reset contact 6, the capacitor C1 is charged and the transistors TR1, TR2 are conducting, their emitters each at a high level.

Therefore, regardless of the operation of the door switch Sd and the window switch Sw, the output of the NAND circuit is at a low level, the output of N0T1 is also at a low level, and the transistors TR3 and TR4 are non-conductive.

Since the input terminal of N0T2 is grounded through the diode D2 and the reset contact 6, it becomes low level, and the output terminal becomes high level, transistor TR is conductive, capacitor C2 is discharged, and capacitor C3 is charged.

Also, since the input terminal of N0T3 is at a low level and its output terminal is at a high level, the transistor TR6 becomes non-conductive, and the transistors TR7 and TR8 also become non-conductive.

Therefore, neither the caution signal generator ■ nor the alarm device ■ will sound.

At this time, capacitor C4 is discharging via diode D3.

(11) When the select switch is in the set state and the door is opened (see Figure 2 a and b).

When a family member goes out and switches the movable contact 5 of the select switch Ss to the set contact 7, the transistor TR2 immediately becomes non-conductive, but since the window switch Sw is closed, the input terminal of N0T1 is at a high level. , its output end is still kept at low level.

The charge in the capacitor C1 is prevented from flowing backward by the diode D1, and is discharged through the transistor TR1 with a time constant determined by the resistors R, R5, keeping the transistor TR1 conductive for about 30 seconds. is still held at a high level G.

Therefore, when a family member goes out, he sets the select switch Ss, opens the door, closes it, and leaves the house.
If it is within 0 seconds, even if the door switch Sd is opened, the warning signal generating device (2) and the alarm device 0 will not operate and will not sound.

Next, select switch S8 is set, and then press button 3.
If the door is opened due to illegal intrusion after o seconds have elapsed, the door switch Sd is opened.

At this time, the transistor TR1 is already in a non-conducting state, so one input terminal of the NAND circuit is at a low level, and since the window switch Sw is closed, the other input terminal of the NAND circuit is at a high level, so the output terminal changes to high level, making transistor TR3 conductive, capacitor C2 is instantaneously charged, the input terminal of N0T3 changes to high level, and the output terminal changes to low level.

At this time, the capacitor C3 is discharged through the transistor TR5, and the transistor TR5 is in a non-conducting state.

When the output terminal of N0T3 changes to a low level, the transistor TR6 is made conductive and the attention signal generator (2) is activated immediately.

When the transistor TR6 becomes conductive, it charges the capacitor C4 through the resistor R15, and the resistor R15 and the capacitors C and l
The charge gradually increases to 0 with a predetermined time constant, and when about 10 seconds have elapsed since the transistor TR6 turned on, the transistor TR8 is made conductive, and the warning signal generating device (2) is activated, followed by the alarm device (2).

If the door switch Sd is opened 1 inch, the battery power E will run out (1), and the warning signal (■) and the alarm system (■) will continue to sound.

Even if the door is closed in this state and the door switch Sd is closed, the transistor T is used for the time during which the capacitor C2 is gradually discharged through the resistors R12+R13, that is, approximately 2 minutes.
R6 continues to be conductive, and the caution signal continues to sound, so that the transistor TR8 is also conductive during this time, giving an alarm, and the caution signal and alarm are also corrected when the capacitor C2 is finished discharging.

0 [D When the select switch is set and the window is opened (see Figure 2C).

When the movable contact 5 of the select switch Ss is switched to the set contact 7, if the window is opened due to illegal intrusion, the window switch Sw is opened, and as a result, one of the input terminals of N0T1 and the input terminal of the NAND circuit becomes low. change to the level,
The output terminal of the NAND circuit becomes a high level, transistor TR3 becomes conductive, and as in the case (1[) above, the caution signal generator ■ is immediately activated to issue a caution signal, and N0
Since the output of T1 also changes to high level, the transistor TR
, conducts, the capacitor C4 is momentarily charged via the transistor TR, and accordingly, the transistor T
R8 is made conductive momentarily and an alarm is immediately generated.

As long as the window is open, this circuit will remain in this state,
When the battery power E runs out 1, the alarm continues to sound, and the window is closed. Both input terminals of the NAND circuit become high level, and its output terminal becomes low level, making the transistor TR3 non-conductive. After approximately 2 minutes of warning signals and alarms, as well as with the door partially closed, they cease to sound.

(IV) When the select switch is changed from the set state to the reset state (see Figure 2C).

When both the door switch 3d and the window switch Sw are closed, even if the select switch Ss is switched from the set state to the reset state, the capacitor C0 is charged again and the capacitor C2 is discharged.

The caution signal generating device (■) and the alarm device (■) are inoperative.

If both the door switch Sd and the window switch Sw are opened, or either one of them is open, both the caution signal generator ■ and the alarm device [F] are operating, or only the caution signal generator During operation, select switch S
8 is switched from the set state to the reset state, capacitor C1 is recharged, and the input terminal of N0T2 goes to low level and its output terminal goes to high level and capacitor C3
is gradually charged, and after a time constant determined by resistor R10s capacitor C3, that is, about 10 seconds, transistor TR5 is made conductive, changing the input terminal of NoT3 from a high level to a low level, and accordingly, the output terminal of N0T3 becomes low. By changing the level to a higher level than the above level, the transistor TR6 is made non-conductive, and the operation of the caution signal generator ■ is stopped, and the capacitor C4 is discharged via the resistor R1□ and the diode D3, so that the transistor TR8 is also made non-conductive. The alarm will also stop.

That is, the caution signal and alarm will be stopped approximately 10 seconds after switching from the set state to the reset state.

It is clear that the invention is not limited in its application to the protection of doors and windows, but can also be applied to other objects with similar purposes.

As explained above, according to the present invention, the alarm device can be miniaturized by using IC-based semiconductor devices and electronic components, and can be used to selectively use caution signals and alarms based on functional differences, such as doors and windows. Furthermore, by closing the door or window from the outside even when no one in the household is present, the warning signal generating device and alarm device will automatically stop, causing no noise pollution, and can be configured with only one central switch. There are other effects.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the anti-theft alarm device according to the present invention, and FIG. 2 a, b, c, and d show operation waveforms of the main parts during each operation of the present invention, respectively. E...Battery power supply, ■...Caution signal generator, ■...Alarm device, Ss...Select switch, sd...Door switch for sw
...Window switch, TR1 to TR8...
・Switching transistor, R1-R17...
・Resistor, C1~C4...Capacitor, D1~
D3...Reverse current blocking diode, NAND...
...NAND circuit, N0T1 to N0T3...
Knot circuit, 5...Movable contact of the select switch, 6...Reset contact of the select switch,
7...Select switch set contact.

Claims (1)

[Claims] 1. A select switch for setting or resetting an anti-theft alarm device that issues an alarm against illegal entry through a door or window, and a first switch device that responds to opening and closing of the door; a first timer circuit that outputs a predetermined timer signal when the select switch is set and outputs a signal corresponding to opening and closing of the first switch device; and a second switch device that responds to opening and closing of the window. , a logic circuit that receives signals from the first and second switch devices as input signals, a third switch device that instantaneously operates and charges a capacitor based on the output signal from the logic circuit, and a fourth switch device that operates in accordance with the operation of the switch device; a caution signal generator that operates in response to the operation of the fourth switch device; and a warning signal generating device that operates in accordance with the operation of the fourth switch device; a fifth switch device that blocks the output of the fourth switch device; a sixth switch device that operates after a predetermined time period under the condition that the fourth switch device operates; and an alarm device that operates via the sixth switch device. An anti-theft alarm device characterized in that it emits a caution signal and an alarm signal in response to the opening and closing of door and window switches.