JPS5828310Y2 - burglar alarm device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a theft alarm device.

Conventionally, anti-theft measures for automobiles and the like mechanically disable rotation of both wheels using a key.

It is based on methods such as

Although this method is quite effective, it loses one function if the entire bicycle is stolen.

The present invention was developed in view of the above points, and aims to improve the security of anti-theft measures by sensing the vibrations that occur when the property is moved when it is stolen. This is intended to be warned by a desired means such as a buzzer.

The figure is a circuit diagram showing an embodiment of the present invention. In the figure, 1 is a vibration sensor whose contacts open and close in response to vibrations, and 2 is a switch that receives and receives output signals from the vibration sensor 1. Then, an NPN transistor Tr1, which is a switch circuit that normally maintains an off state and becomes an on state, has a positive voltage applied to its base and a negative voltage directly applied to its emitter via the vibration sensor 1 and the resistor r1, The transistor Tr1
A PNP transistor Tr2 has a base and a collector connected to the collector and base of the transistor Tr2, respectively, and a resistor r2 is connected between the base and the base of the casing.

A reset circuit 3 instantaneously applies a positive voltage to the base of the transistor Tr2 of the switch circuit 2 to release the on state of the switch circuit 2, and is composed of a series circuit of a bush switch Sl and a capacitor Cc. .

4 is a card sensor, which consists of a board on which a plurality of contacts (for example, A, B, C, etc.) are arranged at appropriate intervals, and a card with a similar structure that comes into contact with each contact on the board. , it is planned that only predetermined contacts will be connected.

Although the figure shows the circuit on the board side, the contact points can be selected arbitrarily, but in this embodiment, A is the base of the transistor Tr2, and B is the positive terminal of the power supply Bb via the resistor RA. The negative electrode side of the power source Bb is connected to the side and C via the resistor RB, and the other contacts are appropriately connected to each other.

Here, the relationship between the resistors RA and RB is RA>RB.

Reference numeral 5 designates a desired alarm such as an electromagnetic buzzer or a speaker equipped with an oscillation circuit, which has one end connected to the emitter of the transistor Tr2 of the switch circuit 2 and the other end connected to the positive side of the power source Bb.

Next, the operation will be explained.

When the property (for example, a bicycle) is moved in an attempt to be stolen, the vibration at that time activates the vibration sensor 1, and the switch 1 is temporarily turned on.

As a result, the base current of Trl flows, and the emitter-collector becomes conductive.

At the same time, conduction is established between the emitter and collector of Tr2, so even if the vibration sensor 1 is turned off, both Tr1 *
Tr2 continues to maintain the on state.

Incidentally, since the alarm device 5 is connected in series to the power source Bb via the switch circuit 2, the circuit 2 continues to be driven in the on state.

To stop this, if the switch S1 of the reset circuit 3 is closed, Tr2 is temporarily turned off, and therefore Trl
is also turned off, and the alarm device 5 is disconnected from the power source Bb.

This reset circuit 3 makes it possible to stop the alarm in the event of an erroneous movement.

However, this reset circuit 3 cannot be misused.

In other words, if the alarm device 5 is activated again, the alarm device 5 will be activated in the same way, so depending on the reset circuit 3, the activation of the alarm device 5 cannot be stopped after all.

Once upon a time, capacitor Cc lI'1Tr of reset circuit 3
A positive voltage, which is a reverse voltage, can be applied only temporarily to the base of the alarm 5, thereby preventing the alarm 5 from being disabled due to the continuous closing operation of the switch S□.

In this way, the alarm device 5 can be temporarily stopped by resetting, but other than that, it always operates according to the operation of the vibration sensor 1, and can thereby generate an alarm.

On the other hand, when using the property (bicycle) by oneself, by inserting a designated card into the card sensor 4,
If only the contact between -8 is connected, a reverse voltage will be applied to Tr2, and the circuit will not work even if the vibration sensor 1 is turned on.

However, a problem arises when a card other than the specified one is inserted and the connection status is different.

For example, when A, B, and C are all connected, or when A and C are connected, forward current flows through Tr2, switch circuit 2 is turned on, and alarm 5 is activated.

! If A and B or C are not connected, it is the same as not inserting the card, so if it is moved, switch 1 will generate an alarm.

In the above embodiment, the switch circuit 2 is constructed of transistors, but it may also be constructed of thyristors.

As explained above, according to the present invention, if an attempt is made to illegally move property (such as a bicycle) to which this device is attached, if the card is not inserted into the card sensor. The system detects the vibrations that occur at this time and uses an alarm such as a buzzer to notify you of this, so it can also prevent theft that could not be prevented using conventional so-called mechanical keys alone. You can expect it.

[Brief explanation of drawings]

The figure is a circuit diagram showing an embodiment of the present invention. 1-... Vibration sensor, 2... Switch circuit, 3... Reset circuit, 4... Card sensor, 5... Alarm. vessel.

Claims (1)

[Scope of utility model registration request] A vibration sensor, a switch circuit that is turned on by activation of the vibration sensor, a reset circuit that arbitrarily releases the switch circuit from the on state, and a predetermined contact among the plurality of contacts are connected. and a card sensor that always turns off the switch circuit only when the switch circuit is turned off, and a desired alarm is activated according to the on/off state of the switch circuit.