JP2002334380A - Anti-theft sensor and anti-theft device - Google Patents

Abstract

(57) [Problem] To provide a sensor for an anti-theft device and anti-theft device with high anti-theft reliability. An anti-theft device comprising: an anti-theft device main body that issues an alarm based on the open / close state of a push switch provided with a conductive coil spring that biases the head to protrude from a head; The spring 43 includes one end of a large-diameter coil spring portion 43a and one end of a small-diameter coil spring portion 43b,
A first abutment with the other end of the small-diameter coil spring portion 43b
An electrode 51, a second electrode 52 disposed so as to be in contact with the other end of the large-diameter coil spring portion 43a, and a third electrode 53 provided outside the small-diameter coil spring portion 43b; 52 and 53 are electrically connected to the first electrode 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor for an anti-theft device for detecting a state of attachment to an object to be stolen and an alarm device for issuing an alarm based on the state of attachment to the object.

[0002]

2. Description of the Related Art FIG. 10 is a perspective view showing an anti-theft device disclosed in Japanese Patent Application Laid-Open No. 2000-187779.
FIG. 1 is an explanatory view for explaining a use state of the anti-theft device.

In FIG. 1, reference numeral 1 denotes a sensor attached to an object to be stolen, and reference numeral 2 denotes an anti-theft device which issues an alarm when the sensor 1 is not in a predetermined state. The sensor 1 transmits a signal indicating a state of attachment of the head 3 to the main body of the anti-theft device, a head 3 for fixing the object to be stolen, a loop code 8 having both ends of a single-core cord fixed to one end of the head 3. A curl cord 4 in which one end of a two-core cord is fixed to the other end of the head 3. The other end of the curl cord 4 is connected to two lead cords 6, 6 via a fixture 5, and the ends of the lead cords 6, 6 have pin-shaped lock pins 7, which connect the anti-theft device main body 2. 7 is provided.

An opening 33 is provided on the bottom surface of the head 3, and a lever 36 of a push switch 41 projects from the opening 33 so as to be able to advance and retreat. The lever 36 is urged in a direction to separate from the head 3. When a required pushing force is applied to the lever 36, the lever 36 retreats into the head 3, the push switch 41 closes, and the pushing force Is removed, the lever 36 projects out of the opening 33, and the push switch 41 is opened.

The anti-theft device main body 2 includes a push switch 4
1, a detection circuit for detecting the open / close state, a battery, a buzzer for issuing an alarm, and the like. Further, one end surface of the anti-theft device main body 2 is provided with two insertion cylinder portions 27, 27 for internally fitting the lock pins 7 of the lead cord 6, and a lock mechanism for locking the lock pins 7 is provided. .

In order to prevent an object by such an anti-theft device, as shown in FIG. 11, a head 3 passed through a loop cord 8 wrapped around a closed area of the object T is used. Then, the lever 36 of the push switch 41 incorporated in the head is pressed against the object T and fixed with the double-sided adhesive tape 30. In this case, the lever 36 is
And the push switch 41 is closed. After the curl cord 4 and the lead cords 6, 6 connected to the head 3 are passed through the back net 62 of the product shelf 61 on which the object T is placed, the lock pins 7, 7
Of the insertion cylinder 27, 2 provided in the anti-theft device 2
7 and locked. In this state, the detection circuit built in the antitheft device main body 2
Is closed, and it is determined that the head 3 is in the predetermined mounted state, and no alarm is issued.

On the other hand, when the head 3 is peeled off from the object, the push switch 41 is opened by the lever 36 projecting out of the opening 33, and the detection circuit of the antitheft device 2 detects this. Alarm to prevent theft. Further, when the loop code 8, the curl code 4, or the lead code 6 is cut,
When the lock pin 7 of the anti-theft device main body 2 is pulled out from the anti-theft device main body 2, the detection circuit of the anti-theft device main body 2 becomes in the same state as the open state of the push switch 41, and issues an alarm. As a result, the object T is prevented from being stolen.

[0008]

SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open
In the anti-theft device disclosed in 000-187779, when the head 3 is attached to the object T with a double-sided adhesive tape and the lever 36 of the push switch 41 is retracted into the head 3, the push switch 41 Since the circuit is in a closed state and no alarm is issued, the object T
The thin blade is inserted between the head 3 and the lever 36, and the lever 36 is pressed into the interior of the head 3, and the thin blade and the head 3 are fixed with, for example, an adhesive tape. Can be removed from the object T.

Further, when the covering of the lead cords 6 and 6 is stripped and short-circuited, the detection circuit of the anti-theft device main body is in the same state as the state where the push switch 41 is closed. By cutting the curl cord 4 at a location close to the head 3, there is a problem that the head 3 can be removed from an object to be prevented from being stolen without issuing an alarm.

The present invention has been made in view of the above circumstances, and urges the operating portion of a push switch to the outside of a housing by a spring having a large-diameter coil spring portion and a small-diameter coil spring portion, and By providing the second electrode and the third electrode capable of contacting the large-diameter coil spring portion, no alarm is issued even when a thin blade is inserted between the housing and the object to be stolen. An object of the present invention is to provide a sensor for an anti-theft device that cannot be put into a state.

[0011] Another object of the present invention is to provide a case where the operating portion of the push switch is retracted into the housing by a predetermined length or more.
And when the operating part of the push switch protrudes beyond the predetermined length to the outside of the housing, the push switch is closed so that a thin blade is inserted between the housing and the object to be stolen. It is another object of the present invention to provide a sensor for an anti-theft device which cannot be set in a state in which an alarm is not issued.

Still another object of the present invention is to provide a sensor for an anti-theft device which has a first diode connected in parallel with a push switch and which can detect a short circuit of a conductor for transmitting an open / closed state of the push switch to an alarm. To provide.

Still another object of the present invention is to provide a second switch connected in series with a push switch, wherein the first diode is connected to the first switch.
It is an object of the present invention to provide a sensor for an anti-theft device which can detect a short circuit of a conductor for transmitting an open / closed state of a push switch to an alarm body by connecting an anode of the diode and a cathode of the second diode.

Still another object of the present invention is to provide a first anti-theft device which further comprises first and second light-emitting diodes which emit light based on the open / closed state of a push switch so that the user can visually check the mounted state of the housing. An object of the present invention is to provide a sensor.

Still another object of the present invention is to provide a sensor for an anti-theft device, detecting means for detecting a closed state of a push switch and a non-conductive state of the conductor, and detecting a closed state of the push switch. An object of the present invention is to provide an anti-theft device having a high reliability of anti-theft by providing an alarm which emits an alarm when a non-conducting state of the conductor is detected.

[0016]

A sensor for an anti-theft device according to a first aspect of the present invention is connectable via a cylindrical connecting portion provided on an alarm which issues an alarm. A housing provided with an opening at a contact surface for contacting an object, a pin-shaped operation unit inserted into the opening so as to be able to advance and retreat, and a means for operating the operation unit through the opening. And a push switch provided with a conductive spring for biasing,
In the sensor for an anti-theft device that is configured to adhere the contact surface to an object and that detects an attached state / removed state of the push switch based on an open state / closed state of the push switch, the spring includes: One end of the large-diameter coil spring portion and one end of the small-diameter coil spring portion are continuous, and the first electrode contacted to the other end of the small-diameter coil spring portion and the other end of the large-diameter coil spring portion can be contacted. A second electrode disposed, a third electrode provided outside the small-diameter coil spring portion, a conductor having one end connected to the housing, and transmitting an open / closed state of the push switch; and a second end of the conductor. And a fitting portion that fits inside the connecting portion, and the second and third electrodes are electrically connected to the first electrode.

A sensor for an anti-theft device according to a second invention is
The push switch is configured such that, when the operation unit has advanced outside the housing by a predetermined length or more, the large-diameter coil spring unit and the second electrode come into contact with each other to close the circuit, and the operation unit is located inside the housing. The large-diameter coil spring portion and the third electrode come into contact with each other to close when the wire is retracted by a predetermined length or more.

A sensor for an anti-theft device according to a third aspect of the present invention comprises:
It further comprises a first diode connected in parallel with the push switch.

A sensor for an anti-theft device according to a fourth aspect of the present invention comprises:
A second diode connected in series with the push switch, wherein an anode of the first diode is connected to the second diode;
And the negative electrode of the diode is connected.

A sensor for an anti-theft device according to a fifth aspect of the present invention comprises:
The first and second diodes are light emitting diodes.

An anti-theft device according to a sixth aspect of the present invention detects the anti-theft device sensor according to any one of the first to fifth aspects, and detects a closed state of the push switch and a non-conductive state of the conductor. It is characterized by comprising a detecting means, and an alarm which issues an alarm when detecting a closed state of the push switch and detecting a non-conductive state of the conductor.

In the first invention, the second invention and the sixth invention, the four corners of the housing are attached to the object to be stolen by double-sided adhesive tape, and then provided on the alarm body, for example. When the push switch is closed without performing a predetermined operation such as turning on an alarm release switch, an alarm is issued. When installed in this way, a gap is created between the contact surface of the housing and the target object by the thickness of the double-sided adhesive tape,
The operation part of the push switch protrudes from the contact surface. Inside the housing, the large-diameter coil spring portion is separated from the second electrode and the third electrode disposed so as to be in contact with the large-diameter coil spring portion, and no alarm is issued because the push switch is in an open state.

However, when the housing is peeled off from the object, the operating portion of the push switch protrudes from the contact surface by a predetermined length or more, and the large-diameter coil spring portion comes into contact with the second electrode to issue an alarm. When a thin blade is inserted into the gap between the abutment surface of the housing and the object in order to peel it off from the object while holding the operation unit inside the housing, the operating part of the push switch is pressed by the thin blade. When the operating unit is pushed into the housing by a predetermined length or more, the large-diameter coil spring contacts the third electrode to close the push switch, and the alarm detects the closing of the push switch and issues an alarm. Emits. For this reason, it is difficult to insert the thin blade and peel off the housing without issuing an alarm, and the effect of preventing theft can be enhanced.

In the third invention and the sixth invention, since the first diode connected in parallel with the push switch is provided, for example, the alarm switch is connected to the push switch and the first diode via a conductor. When an AC signal is input to the connection node, a signal having one polarity is output when the push switch is open, and a signal having both polarities is output when the push switch is closed. Therefore, it is possible to prevent theft by issuing an alarm when the signal detected by the alarm has both polarities.

According to the fourth and sixth aspects of the present invention, there is further provided a second diode connected in series with the push switch, wherein the anode of the first diode is connected to the cathode of the second diode. For example, when an AC signal is input from a warning body to a common connection node between the push switch and the first diode via a conductor, the first switch connected in parallel with the push switch when the push switch is open is opened. Only one polarity signal passing through the diode is output. However, when the push switch is closed, the signal output from the housing has both polarities. The alarm detects these signals and issues an alarm to prevent theft. Also, if the conductor that transmits the open / closed state of the push switch to the alarm body is short-circuited,
The signal detected by the alarm is a signal having both the same polarity as that of the state in which the push switch is closed. The alarm detects this signal and issues an alarm, thereby preventing theft.

According to the fifth and sixth aspects of the present invention, since the first and second light emitting diodes that emit light based on the open / closed state of the push switch are provided, it is possible to visually check the mounting state of the housing. It is possible to enhance the effect of preventing theft.

[0027]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a perspective view showing an anti-theft device according to the present invention, in which 1 is a sensor attached to an object to be stolen, and 2 is an anti-theft device which issues an alarm when the sensor 1 is not in a predetermined state. It is an apparatus main body. FIG. 2 is a perspective view of the anti-theft device main body 2,
FIG. 3 is a perspective view of the sensor 1.

Inside the horizontally long box-shaped anti-theft device main body 2,
A power supply, an oscillating circuit for generating an AC signal, a buzzer for generating an alarm, and a control circuit for operating the buzzer based on the mounting state of the sensor 1 are provided. A window 24 for emitting light and n sets (for example, n = 3) of light emitting diodes 21a and 21b that emit light in accordance with the mounting state of the sensor 1 are provided.

On the outer surface of the anti-theft device main body 2, n sets of insertion tube portions 27, 27 have end portions protruding at appropriate intervals, and inside the insertion tube portions 27, 27, A mechanism for locking the lock pins 7 provided on the sensor 1 is connected.

The two lock pins 7 provided on the sensor 1 are formed by covering a base end of a conductive pin-shaped member with an insulator, and have a signal line made of stainless steel such as SUS304 at one end. Are coated with lead cords 6 and 6, respectively. The two lead cords 6 and 6 are connected to the curl cord 4 via the fixture 5, and the curl cord 4 is a two-core cord formed by covering two stainless steel signal lines such as SUS304 with a polypropylene material. The intermediate portion is subjected to a spring process of helically winding the bar and heating the bar, and is connected to one side surface of the rectangular head 3.

An opening 33a (see FIG. 4) is formed in the center of the bottom surface of the head 3, and a double-sided adhesive tape 30 having a thickness of about 1 mm is attached to four corners or the periphery of the bottom surface of the head 3. A push switch 41 to be described later is provided in the head 3, and a lever 3 serving as an operation unit of the push switch 41 is provided.
A part of 6 protrudes from the opening 33a so as to be able to advance and retreat.

FIGS. 4 and 5 are side sectional views of the head 3 shown in FIG. The head 3 is configured such that the bottom opening of the first member 31 having a rectangular dome shape is closed by a second member 32 having a flat plate shape.
Has been established. A guard electrode 50 is provided upright around the opening 33 a on the inner surface of the second member 32. Guard electrode 5
Numeral 0 indicates that the bottom opening of the cylindrical third electrode 53 is closed by a disk-shaped second electrode 52, and an opening 33 b having the same diameter as the opening 33 a is opened at the center of the second electrode 52. It is. Further, the guide portion 3 for guiding the lever 36 of the push switch 41 around the opening 33b on the inner surface of the second electrode.
4a is erected. A large-diameter spring portion 43a of a coil spring 43 described later is provided on a top plate of the third electrode 53.
An opening 33c having a diameter smaller than the outer diameter of the small-diameter spring portion 43b and larger than the outer diameter of the small-diameter spring portion 43b is provided. Further, a protruding member is formed so as to protrude from a part of the outer edge portion of the second electrode 52, and a folded portion which is folded at a right angle is provided at an end of the protruding member.

A lever 36 made of a synthetic resin is loosely fitted in the guard electrode 50 by a coil spring 43 abutting on a printed circuit board 40 described later, and guides the coil spring 43 on the printed circuit board 40. Guide part 3
4b is erected. The push switch 41 is configured by the lever 36, the coil spring 43, and the printed board 40.

The lever 36 has a diameter smaller than the inner diameter of the small-diameter spring portion 43b on both end surfaces of a cylindrical support portion 37 having a diameter larger than the diameter of the opening portion 33b, and is brought into contact with an object. A contact portion 38a and a columnar contact portion 38b to be brought into contact with the printed circuit board are projected from each other, and the diameter of the end of the contact portion 38a gradually increases toward the tip. The contact portion 38a is arranged so as to be able to protrude outside from the opening 33a of the second member 32, and the contact portion 38b is arranged so as to be able to project outside from the opening 33c of the third electrode.

The coil spring 43 is integrally formed of spring steel having excellent conductivity, and has a large diameter spring portion 4.
One end of 3a and one end of the small diameter spring portion 43b are connected and arranged coaxially. The dimension of the coil spring 43 in the axial direction is substantially the same as the thickness of the head 3, and FIG.
As shown in FIG. 8, when the lever 36 is urged toward the second member 32 by the elastic force of the small-diameter spring portion 43b, the contact portion 38a protrudes from the opening portion 33a by a predetermined length or more. The portion 43a is in contact with the second electrode 52.

As shown in FIG. 5, the head 3 is adhered and fixed to the object by the double-sided adhesive tape 30, and the contact portion 38
a is brought into contact with the object T, the lever 36
And the elastic force received from the small-diameter spring portion 43b is balanced by the large-diameter spring portion 43a.
The size of the large-diameter spring portion 43a in the axial direction is determined so as not to contact any of the second and third electrodes 53.

The diameter of the end of the contact portion 38a is gradually increased toward the distal end.
Insertion of a thin blade between a and the object T is suppressed.

FIG. 6 shows a printed board 40 of the curl code 4.
FIG. 4 is an explanatory diagram for explaining a connection state to a server. A fourth electrode 54 and a fifth electrode 55 are provided at both corners of one end of the substantially rectangular printed board 40, respectively.
Sixth electrodes 56a and 56b and seventh electrodes 57a and 57b are provided, respectively. In addition, the first substrate
An eighth electrode 58 is provided between the electrode 51 and the first electrode 51 and the other end of the printed circuit board 40.

The first electrode 51, the fourth electrode 54, and the sixth electrode 56a are electrically connected to each other.
The fifth, sixth electrode 56b, and seventh electrode 57b are electrically connected to each other, and the seventh electrode 57a and the eighth electrode are electrically connected.

Sixth electrode 56a, 56b and seventh electrode 57
A small through-hole is opened at the center of each of the sixth electrodes 56a and 56b.
Are connected to a cathode and an anode of a light emitting diode 11a that emits green light, respectively.
The anode and the cathode of the light emitting diode 11b which emits red light are connected to 7b, respectively.

One signal line 4 a in the curl cord 4 is connected to the fourth electrode 54 by soldering.
, The other signal line 4b in the curl cord 4 is connected by solder. Further, the folded portion of the protruding member of the guard electrode 50 is in contact with the eighth electrode 58.

FIG. 7 is a block diagram showing a configuration example of the sensor 1 and the anti-theft device 2. One terminal of the push switch 41 is connected in series to the anode of the light emitting diode 11b that emits red light via the second electrode 52 or the third electrode 53, and the other terminal of the push switch 41 emits green light. The common connection node between the other terminal of the push switch 41 and the cathode of the light emitting diode 11a is connected in parallel with the cathode of the diode 11a, and the oscillator O in the antitheft device main body 2 is connected via the lead cord 6.
Connected to SC. The oscillator OSC is driven by a power supply (not shown) to generate an AC signal.

The light emitting diode 21a emitting green light and the light emitting diode 21b emitting red light provided in the antitheft device main body 2 are connected in series with resistors Ra and Rb, respectively, and both light emitting diodes 21a and 21b are connected to an oscillator OSC.
Are connected in parallel. Light emitting diode 21a
Is a phototransistor 22 that receives the light it emits
a constitutes a photocoupler. Similarly, the light emitting diode 21b and the phototransistor 22b that receives light emitted from the light emitting diode 21b constitute a photocoupler. The emitters of the phototransistors 22a and 22b are grounded, and the collectors are connected to resistors Rc and Rd, respectively. A common connection node between the phototransistor 22a and the resistor Rc is grounded via an electrolytic capacitor Ca, and has a display circuit DIS and an exclusive OR circuit E.
It is connected to one input terminal of XOR. Similarly, a common connection node between the phototransistor 22b and the resistor Rd is grounded via the electrolytic capacitor Cb and is connected to the other input terminal of the display circuit DIS and the exclusive OR circuit EXOR. Exclusive OR circuit EXOR
Is inverted by the inverter INV,
Buzzer BUZ that is input to control circuit CON and issues an alarm
It is connected to the.

In the sensor 1 and the antitheft device main body 2 having such a circuit configuration, when the head 3 of the sensor 1 is installed in contact with the object T as shown in FIG. And the exclusive OR circuit EXO
A signal is input to only one terminal of R. In this case, the exclusive OR circuit EXOR outputs a high level signal,
The output of the inverter INV becomes low level (0 V).
In this state, the light emitting diode 1 that emits green light
Only 1a and 21a emit light.

When the head 3 of the sensor 1 is peeled off from the object T and the large-diameter spring portion 43a of the coil spring 43 comes into contact with the second electrode 52, or when the lever 36
Is pushed into the inside of the head 3 and the large-diameter spring portion 4
When the switch 3a comes into contact with the third electrode 53, that is, when the push switch 41 is closed, the exclusive OR circuit EXO
A signal is input to both terminals of R, and a low level signal is output, and the output of the inverter INV becomes high level. The control circuit CON detects this high-level signal and sounds the buzzer BUZ. Furthermore, in this state,
The light emitting diodes 11a and 21a that emit green light and the light emitting diodes 11b and 21b that emit red light both emit light.

When the read codes 6 and 6 are disconnected, no signal is input to any of the terminals of the exclusive OR circuit EXOR, a low-level signal is output, and the output of the inverter INV is changed to a high-level signal. Become. In the control circuit CON,
The buzzer BUZ is sounded by detecting this high level signal. In this state, all the light emitting diodes 1
1a, 11b, 21a, and 21b do not emit light.

Further, when the covering of the lead codes 6 and 6 is stripped and short-circuited on the way, a signal is input to both terminals of the exclusive OR circuit EXOR as in the case where the push switch 41 is closed. Thus, a low level signal is output, and the output of the inverter INV becomes a high level signal. The control circuit CON detects this high-level signal and sounds the buzzer BUZ. In this state, the light emitting diodes 21a, 21a provided inside the anti-theft device main body 2 are provided.
b emits light.

Therefore, when the head 3 of the sensor 1 is peeled off from the object T and the large-diameter spring portion 43a of the coil spring 43 comes into contact with the second electrode 52 (push switch 41 is closed), the lever 36 The large-diameter coil spring portion 43a is pushed into the inside and the third electrode 5
3 (the push switch 41 is closed), when the lead cords 6, 6 are cut off, or when the lead cords 6, 6 are covered and short-circuited on the way, the same high-level signal is sent to the control circuit CON. Give to. Control circuit CO
In N, when a high-level or low-level signal is received and the received signal is identified as a high-level signal,
Ring the buzzer BUZ.

In this embodiment, an example is described in which the oscillator OSC is driven by the power supply inside the anti-theft device main body 2, but an external commercial AC power supply may be used.

FIG. 8 is an explanatory view for explaining a state in which the antitheft device according to the present invention is mounted on an object. Product shelf 61
A plurality of objects T such as cameras, for example,
Push switch 4 built in the head 3 of the anti-theft device
One of the levers 36 is brought into contact with the object T to be stuck and fixed.
Further, two lead cords 6, 6 are passed through the back net portion 62 of the product shelf 61, and lock pins 7, 7 respectively provided at the tips of both lead cords 6, 6 are inserted into the two insertion cylinder portions 2.
7. Insert and lock into 7, 27 respectively.

As described above, by attaching the antitheft device to the object T, the customer can rotate or lift the object T for examination. On the other hand, when the head 3 of the anti-theft device is removed from the object T or the curl code 4 or the lead codes 6 and 6 are cut to steal the object T, the anti-theft device main body 2 issues an alarm. Emit.

As shown in FIG. 9, when the thin blade 60 is inserted into the contact surface between the head 3 and the object T in order to separate the head 3 from the object T, the tip of the thin blade 60 As a result, the large-diameter spring portion 43a of the coil spring 43 comes into contact with the third electrode 53, and the antitheft device main body 2 issues an alarm.

Incidentally, reference numerals are written in the claims for convenience of comparison with the drawings, but the present invention is not limited to the structure of the accompanying drawings by the entry.

[0054]

As described in detail above, the first invention and the second invention
In the case of the invention and the sixth invention, after the four corners or the periphery of the housing are stuck to the object to be stolen by double-sided adhesive tape, for example, a predetermined operation such as turning on an alarm release switch provided on the alarm body is performed. If the push switch is closed without performing the above operation, an alarm is issued. When installed as described above, a gap is created between the contact surface of the housing and the target object by the thickness of the double-sided adhesive tape, and the operating portion of the push switch projects from the contact surface. Inside the housing, the large-diameter coil spring portion is separated from the second electrode and the third electrode that are disposed so as to be in contact with the large-diameter coil spring portion, and the push switch is opened, so that no alarm is issued.

However, when the housing is peeled off from the object, the operating portion of the push switch protrudes from the contact surface by a predetermined length or more, and the large-diameter coil spring portion comes into contact with the second electrode to issue an alarm. When a thin blade is inserted into the gap between the contact surface of the housing and the object in order to peel it off from the object while holding the operation unit inside the housing, the operating part of the push switch is pressed by the thin blade. When the operating unit is pushed into the housing by a predetermined length or more, the large-diameter coil spring contacts the third electrode to close the push switch, and the alarm detects the closing of the push switch and issues an alarm. Emits. For this reason, it is difficult to insert the thin blade and peel off the housing without issuing an alarm, and the effect of preventing theft can be enhanced.

According to the third and sixth aspects of the present invention, since the first diode connected in parallel with the push switch is provided, for example, an AC signal is input to the housing from an alarm and output from the housing. By detecting the polarity of the signal, the open / closed state of the push switch can be identified. By issuing an alarm based on the open / close state of the push switch, the effect of preventing theft can be enhanced.

According to the fourth and sixth aspects of the present invention, there is further provided a second diode connected in series with the push switch, wherein the anode of the first diode and the cathode of the second diode are connected. For example, when an AC signal is input to the housing from the alarm, when the housing is installed in contact with the object, that is, when the push switch is circuited, the switch is connected in parallel with the push switch. Only one polarity signal passing through the first diode is output from the housing. However, when the push switch is closed, the signal output from the housing has both polarities. The alarm detects these signals and issues an alarm to prevent theft. Also, if the conductor that transmits the open / closed state of the push switch to the alarm is short-circuited, the signal detected by the alarm will have both the same polarity as the closed state of the push switch, and the alarm will detect this. By issuing an alarm, theft can be prevented.

According to the fifth and sixth aspects of the invention, the first and second light emitting elements emit light based on the open / closed state of the push switch.
Since the light emitting diode of the present invention is provided, the mounting state of the housing can be visually checked, and the effect of preventing theft can be enhanced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an anti-theft device according to the present invention.

FIG. 2 is a perspective view of the main body of the anti-theft device shown in FIG. 1;

FIG. 3 is a perspective view of the sensor shown in FIG.

FIG. 4 is a side sectional view of the head shown in FIG. 1;

FIG. 5 is a side sectional view of the head shown in FIG. 1;

FIG. 6 is an explanatory diagram illustrating a connection state of a curl code to a printed circuit board.

FIG. 7 is a block diagram illustrating a configuration example of a sensor and an anti-theft device.

FIG. 8 is an explanatory diagram illustrating a state in which the antitheft device according to the present invention is attached to an object.

FIG. 9 is a side sectional view of the head shown in FIG. 1;

FIG. 10 is a perspective view showing a conventional anti-theft device.

FIG. 11 is an explanatory view showing a use state of a conventional anti-theft device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor 2 Anti-theft device main body 3 Head 4 Curl cord 5 Fixture 6 Lead code 7 Lock pin 36 Lever 43 Coil spring 43a Large diameter spring part 43b Small diameter spring part 51 First electrode 52 Second electrode 53 Third electrode

Claims (6)

[Claims] 1. An alarming means (2) for issuing an alarm, which can be connected via a cylindrical connecting part (27) provided on an alarming body (2), and which is opened on a contact surface for abutting an object to be stolen. Hole (33
a) provided with a) and the opening (33a)
A push switch provided with a pin-shaped operating portion (36) inserted into the opening so as to be able to advance and retreat, and a conductive spring (43) for urging the operating portion (36) to advance from the opening (33a). (41), wherein the contact surface is adhered to the object, and the state of attachment to the object /
In the anti-theft device sensor (1) for detecting a detached state based on an open / closed state of the push switch (41), the spring (43) includes one end of a large-diameter coil spring portion (43a) and a small-diameter coil spring portion (43b). ) Is continuous with the first electrode (51) contacting the other end of the small-diameter coil spring portion (43b), and the large-diameter coil spring portion (43a).
One end is connected to the second electrode (52) disposed so as to be in contact with the other end of the third coil, a third electrode (53) provided outside the small-diameter coil spring portion (43b), and the housing (3). Have been
A conductor for transmitting the open / close state of the push switch (41); and a fitting portion (7) provided at the other end of the conductor and fitted inside the connecting portion (27). Wherein the first and second electrodes (52, 53) are electrically connected to the first electrode (51). 2. The large-diameter coil spring portion (43a) and the second electrode when the operating portion (36) has advanced beyond a predetermined length outside the housing (3). (52) comes into contact with the circuit and closes.
(6) that the large-diameter coil spring portion (43a) and the third electrode (53) come into contact with each other to close the circuit when the back is retracted by a predetermined length or more into the housing (3). Sensor (1) for an anti-theft device according to claim 1, characterized in that: 3. The sensor (1) for an anti-theft device according to claim 1, further comprising a first diode (11a) connected in parallel with the push switch (41). 4. The semiconductor device further comprises a second diode (11b) connected in series with the push switch (41), wherein an anode of the first diode (11a) and a cathode of the second diode (11b) are connected. Sensor (1) for an anti-theft device according to claim 3, characterized in that it is connected. 5. The first and second diodes (11a, 11a,
The light emitting diode according to claim 3 or 4, wherein 11b) is a light emitting diode.
The sensor (1) for an anti-theft device according to (1). 6. A sensor (1) for an anti-theft device according to any one of claims 1 to 5, and detection means for detecting a closed state of said push switch (41) and a non-conductive state of said conductor. And an alarming body (2) for issuing an alarm when detecting a closed state of the push switch (41) and detecting a non-conductive state of the conductor.