JPH0850685A - Anti-theft device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent theft of goods. [Structure] When an article is lifted, the switch 1 detects it and becomes conductive. The article is provided with an input device, and the authorized owner inputs the password from this input device when carrying the article. Owner recognition circuit 2
Outputs an alarm prohibition signal for a predetermined time if the input password matches the password stored in advance.
The alarm circuit 3 sounds an alarm and issues an alarm when the alarm prohibition signal is not output and the switch 1 becomes conductive. In this way, it can be announced that the item will be taken away by someone other than the legitimate owner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-theft device which gives an alarm when an article is lifted by a person who is not a legitimate owner or user.

[0002]

2. Description of the Related Art Conventionally, articles that are easy to carry, such as notebook computers, do not have an anti-theft function, so they are put in a locker with a key or are chained to a foot of a desk or the like. He was just trying to prevent theft. Also, in places where many people come and go, security guards checked the belongings to prevent theft.

[0003]

In the above-mentioned conventional antitheft method, there is a problem that the article is taken away when the key is broken or the chain is broken,
Further, when the security guard is checking the belongings, there is a problem that it is not possible to easily judge whether or not the goods are taken out by a legitimate owner or user. The present invention has been made to solve the above problems, and an object of the present invention is to provide an antitheft device that detects that an article has been lifted by a person who is not a legitimate owner or user.

[0004]

According to the present invention, there is provided a switch for detecting that an article is lifted from a table, and an input password coincides with a pre-registered password.
An owner recognition circuit for a legitimate owner that outputs an alarm prohibition signal only for a predetermined time, and an alarm circuit that issues an alarm when there is no output of this alarm prohibition signal and the switch detects that an article has been lifted It is provided in the article. Also, the switch is held by a housing fixed to the article and has first and second fixed contacts connected to an alarm circuit as a switch output, and a first contact point that touches the table when the article is placed on the table. A movable contact that is positioned at a position where it does not contact the first and second fixed contacts and that is released from the table when the article is lifted from the table, and the positioning is released. One end is fixed to the movable contact and the other end is attached to the housing. Is fixed, the article is pushed by the table when it is placed on the table and bends, the movable contact is positioned at a position where it does not contact the first and second fixed contacts, and when this positioning is released. The article is lifted by an elastic body that pushes the movable contact to bring it into contact with the first and second fixed contacts, and when the movable contact contacts the first and second fixed contacts, they are brought into conduction. Detect that It is intended.

[0005]

According to the present invention, the switch detects when an article is lifted from the table. Then, the alarm circuit does not output an alarm if the owner recognition circuit outputs an alarm prohibition signal due to the agreement of the passwords, and the switch detects that the alarm prohibition signal is not output and the article is lifted. Then an alarm is issued. Further, when the article is placed on the table, the movable contact is positioned so as not to contact the first and second fixed contacts by touching the table. Then, when the article is lifted from the table, the positioning of the movable contact is released, and the elastic body pushes the movable contact to contact the first and second fixed contacts, so that the first and second fixed contacts conduct. It becomes a state.

[0006]

1 is a block diagram of an anti-theft device showing an embodiment of the present invention, and FIG. 2 is a sectional view of a switch used in the anti-theft device. In FIG. 1, 1 is a switch for detecting that an article (not shown) is lifted, 2 is an owner recognition circuit for outputting an alarm prohibition signal for a predetermined time when the input password matches a pre-registered password, and 3 is This alarm circuit issues an alarm when the owner recognition circuit 2 does not output an alarm prohibition signal and the switch 1 detects that an article has been lifted.

In FIG. 2, 1a and 1b are first and second fixed contacts made of a conductive material, which are held by a housing 1e fixed to an article and connected to an alarm circuit 3 as a switch output. Reference numeral 1c is a movable contact made of a conductive material, and when the article is placed on the table 5, the movable contact 1c is pushed by the table 5 to be positioned so as not to contact the fixed contacts 1a and 1b, and when the article is lifted. The positioning is released by leaving the table 5.

Further, 1d is a spring which is an elastic body, one end of which is fixed to the movable contact 1c and the other end of which is fixed to the housing 1e, and which is pushed by the table 5 when an article is placed on the table 5. The movable contact 1c is positioned at a position where it does not flex and contact the fixed contacts 1a and 1b, and when the positioning is released, the movable contact 1c is pushed to contact the fixed contacts 1a and 1b. Further, 4 is the bottom surface of the article.

The antitheft device comprising the switch 1, the owner recognition circuit 2 and the alarm circuit 3 is provided inside an article (not shown) such as a notebook computer and prevents the article from being stolen. Next, regarding the operation of such an anti-theft device, the operation when an authorized owner or user carries an article will be described.

An input device such as a keyboard or a bar code reader (not shown) is provided on the article, and the authorized owner inputs the password from this input device when carrying the article. Then, this password is output from the input device to the owner recognition circuit 2. The owner recognition circuit 2 collates the input password with the password stored in advance, and if the corresponding password is stored, the owner recognition circuit 2 determines that the owner is a legitimate owner, and outputs an alarm prohibition signal for a predetermined time (for example, 30 minutes). Is output.

When the alarm prohibition signal is output in this way,
Since the alarm output by the alarm circuit 3 described later is prohibited,
No alarm is given when the item is lifted, and the authorized owner or user can carry the item and move it to another place. Next, the operation when the article is taken away by a person who is not the proper owner will be described.

A switch 1 is fixed to a bottom surface 4 of the article by a housing 1e as shown in FIG. 2, and contacts 1a and 1b of the switch 1 are connected to an alarm circuit 3. When the article is placed on the table 5, the movable contact 1c held by the spring 1d is contacted with the table 5 to determine its vertical position, and at this position, the fixed contacts 1a, 1
No contact with b. As a result, the fixed contacts 1a and 1b are in a non-conductive state.

Then, when the article is lifted from the table 5, the movable contact 1c is also separated from the table 5, so that the determination of the vertical position as described above is released, and the movable contact 1c moves downward by the force of the spring 1d. . By such movement, the surface 10 of the movable contact 1c and the surface 12 of the fixed contact 1a come into contact with each other, and similarly, the surface 11 of the movable contact 1c and the surface 13 of the fixed contact 1b come into contact with each other.

In this way, the movable contact 1c becomes the fixed contact 1a,
By making contact with 1b, the contacts 1a, 1b become conductive. The alarm circuit 3 sounds an alarm and issues an alarm when the owner recognition circuit 2 does not output an alarm prohibition signal and the switch 1 is in the conductive state as described above.

As described above, it is possible to inform that the article is taken away by a person who is not a legitimate owner or user. In the present embodiment, the alarm is issued by issuing an alarm sound from the alarm circuit 3. However, an alarm is issued by a synthetic voice or a specific radio wave is emitted and detected by an external detection device (not shown). You may do it.

[0016]

According to the present invention, an antitheft device including a switch, an owner recognition circuit, and an alarm circuit is provided in an article, so that the article can be lifted by a person who is not a legitimate owner or user. Since the alarm circuit issues an alarm, it becomes difficult to take away the article, and it is possible to easily determine whether the article is taken out by a legitimate owner or user. In addition, the switch is the first, the second
By comprising the fixed contact, the movable contact, and the elastic body, the movable contact comes into contact with the first and second fixed contacts when the article is lifted, and these are brought into conduction.
The switch for detecting that the article is lifted from the table can be realized with a simple configuration.

[Brief description of drawings]

FIG. 1 is a block diagram of an anti-theft device showing an embodiment of the present invention.

2 is a cross-sectional view of a switch used in the anti-theft device of FIG.

[Explanation of symbols]

1 ... switch, 2 ... owner recognition circuit, 3 ... alarm circuit, 4
... Bottom surface of article, 5 ... Stand, 1a, 1b ... Fixed contact, 1c ...
Movable contact, 1d ... Spring, 1e ... Housing.

Claims (2)

[Claims] 1. A switch for detecting that an article is lifted from a table, and a possession for a legitimate owner who outputs an alarm prohibition signal for a predetermined time when the entered password matches a pre-registered password. An anti-theft device, comprising: a person recognizing circuit; and an alarm circuit which outputs an alarm when the switch detects that the article has been lifted without outputting the alarm prohibition signal. 2. The anti-theft device according to claim 1, wherein the switch is held by a housing fixed to an article, and first and second fixed contacts connected to an alarm circuit as a switch output, Movable to be positioned at a position where it touches the table when it is placed on the table and does not contact the first and second fixed contacts, and when the article is lifted from the table, the positioning is released by moving away from the table. A contact, one end of which is fixed to the movable contact and the other end of which is fixed to the housing, and when the article is placed on the table, the article is pushed by the table and bends to contact the first and second fixed contacts. The movable contact is positioned at a position where the movable contact is not positioned, and when the positioning is released, the movable contact is pressed to contact the first and second fixed contacts, and the movable contact includes the first and second movable contacts. Fixed contacts and contacts Anti-theft device, characterized in that in order to detect that the article is lifted by them in a conductive state when the.