GB2049030A - Security devices - Google Patents

Abstract

A device for preventing weapon- carrying persons from entering an enclosed area comprises either a pair of sliding doors (not shown) or a cylindrical housing 1 having an entrance (3, figure 2, not shown) and an exit (4) and within which is rotatively supported a radial-vane door (2) of bulletproof material, the vanes 6 of which define spaces (8), a metal-detector (47, 49, 50, 54, 55, 61, figure 4, not shown) being provided to detect metal objects carried by a person entering a space (8) and then to actuate a solenoid 44 whereby teeth 39, 40 are engaged to lock the door and confine the person. A reduction gear (9) is provided to reverse the rotation of the door to eject the person. The metal detector includes a quartz squarer-oscillator (47) of constant frequency and a controlled oscillator (49) which includes a pick-up coil (50), the output signals of the oscillators (47, 49) being applied to a phase comparator (54) whose output ultimately energises a relay (65) for the solenoid (44). <IMAGE>

Description

SPECIFiCATION Device for preventing weapon carrying persons from entering an enclosed or restricted area This invention relates to a device for preventing weapon carrying persons from entering an enclosed or restricted area. The invention is specially useful as a protection measure from assaults to bank establishments, post offices, and any other valuables containing areas.

Known is that most banks already utilize shatter-proof or bulletproof glass panels to protect their personnel from criminal assailers. Bulletproof glass panels, in fact, do afford bodily protection for such personnel, but leave them powerless before such situations as when the criminals threatens the lives of hostages seized inside the bank and witheld under the menace of arms.

It is a primary object of this invention to provide a device which, additionally to affording bodily protection for any of the personnel and customers present in an assaulted bank, also makes it impossible for criminal assailers to abduct hostages in order to cover themselves or blackmail the bank employees.

This object is achieved by a device for preventing weapon carrying persons from entering an enclosed or restricted area, characterized in that it comprises a cylindrical housing located at the entrance of the enclosed area and provided with an entrance opening and an exit opening effective to place the enclosed area into communication with the outside environment, within said housing there being journalled a door of the radial vane type, said radial vanes defining cylindrical sector spaces, said housing and said door being made of a bulletproof material, and in that a metal object detector is provided for detecting the presence of metal objects carried on or by a person being momentarily located in an enclosed space of said housing and controlling an actuating solenoid of a lock operative to block said door against rotation and hold said metal object carrying person confined within said enclosed space.

Further features of this invention will be more clearly understood by making reference to the following description of a preferred embodiment thereof, illustrated in the accompanying drawings, where: Figure 1 is a general view of the device according to the invention; Figure 2 is a sectional view taken along the line Il-Il of Figure 1; Figure 3 is a more detailed view, in vertical section, of this device and Figure 4 is a block diagram of the metal detector.

The inventive device comprises a cylindrical housing 1, internally whereto a revolving door 2 is arranged. The housing 1 is located at the entrance of an enclosed or restricted area to be protected, i.e. in the wall 5 bordering the enclosed area, wherein the housing is instalied. Apertures 3, 4 are provided on the same side with respect to a diametrical plane through the housing, normal to the wall 5.

The door 2 is so supported as to only revolve in the direction A, such that any persons entering the enclosed area through the opening 3 are compelled to follow the path B, whereas those existing follow the path C.

The door 2 is composed of four vanes 6, arranged to form a cross and made, similar to the housing 1, of a bulletproof material, preferably of a bulletproof glass.

Rotation of the door in the direction A is accomplished by the push applied by an entering or exiting person. A metal detector, to be described hereinbelow, checks that a person entering the enclosed area and following the path B does carry a metal object of a mass exceeding a predetermined value, e.g. a hand gun.

In the affirmative, the metal detector activates a unit 7 which causes the door to become blocked such as to trap that person in one of the cylindrical sector spaces 8 which are defined between two vanes and the housing. The unit 7 is associated with a reduction gear 9 for driving the door 2 in the opposite direction to A, such as to force the person momentarily trapped in the space 8 and reduced to harmless conditions, to move outwards through the opening 3, to be thus identified and possibly delivered to the police authorities.

More specifically, as is apparent from Figure 3, . the door 2 comprises a vertical axle 10, to the opposed ends whereof two respective plates 11, 1 2 are attached wherefrom arms 13, 14 extend radially to provide support for the vanes 6. The plates 11, 12 are provided with axial tailpieces 15, 16, wherewith bearings 17, 18 are engaged for pivotally carrying the door 2 in flanges 19, 1 9a which are centered in a base plate 20 and a further plate 21, such plates closing the housing 1 at the top and bottom. To the upper tailpiece 16, a sleeve 23 is rotatively rigid, through a key 22, which is provided with a ring of axial teeth 24 wherebetween mesh frontally teeth 25 projecting downwardly from an overlying small plate 26.

The small plate 26 is attached to the bottom end of a sleeve 27 which, through a pair of bearings 28, is pivotally carried in a bushing 29.

The bushing 29 is rotatively connected, through a key 30, to a shaft 31 coaxial with the door axle. A snap ring 32 prevents the bushing 29 from sliding axially off. The shaft 31 is the output shaft of the reduction gear 9, resting on the plate 21 through a drum 33, centered with respect and attached to the flange 1 9a, from the tip whereof there extend reduction gear supporting arms 34. The reduction gear 9 is so designed as to cause, when in the stop condition, the shaft 31 to the blocked against rotation, similarly to what happens with the worm and gear type of reduction gears.

The sleeve 26 has a flange 35 which is formed with peripheral notches 36, a ring 37 of a ferromagnetic material resting on said flange which has as the bottom peripheral projections 38 extending downwards and in engagement with the notches 35. Along the top peripheral edge of the ring 37, there is formed a toothing 39 adapted for meshing with an overlying toothing 40 arranged peripherally along a disc 41 keyed to the shaft 31 by means of a coupling key 42.

The disc 41 rests on the bushing 29 with the interposition of a spacer 43 and has an annular groove wherein is located a winding 44 which can be connected to a power supply system through a relay linked to said metal detector. The connection of the winding to the power supply system is accomplished through brushes and cables led through a hole 45 in the drum 33. It will be apparent how the toothings 39, 40 form a clutch assembly, and the winding 44 and disc 41 form a solenoid the energization whereof causes the ring 37 to be pulled and moved upwardly, and the toothing or tooth formation 39 to mesh with the toothing 40.

The device described in the foregoing operates as follows. As a person carrying no metal objects enters the enclosed area protected by the instant device, following the path B, the metal detector remains inactive. Consequently, the winding 44 is not energized and the toothings 39, 40 remain disengaged. Thus, the revolving door 2 is free to rotate in the direction A. By contrast, as a person carrying a metal objects enters the enclosed area, e.g. a criminal assailer armed with a hand gun, the detector is activated, thus causing the winding 44 to become energized and pull the ring 37, thereby the toothings 39 and 40 are caused to mesh together and instantly block the door. The energizing signal is emitted at the moment when a person is located at that sector 8 which happens to be completely enclose by the vanes 6 and housing 1.The bulletproof construction of the vanes and housing puts the assailer in a condition of causing no harm to any persons located nearby.

In order to get the assailer out of its confinement, the reduction gear 9 is operated, by virtue of the shaft 31 and door 2 being coupled through the clutch 37-41 , the sleeve 26 and coupling 23-26, causing the door 2 to revolve or rotate.

Suitably, the rotation of the door occurs in the opposite direction to A, in order to prevent the assailer from gaining access to the enclosed area inside.

The invention has given proof of a high degree of reliability. The difference existing between the metal mass which a person normally carries with himself (keys, coins, etc.) and that of a weapon however small (e.g. a hand gun or pistol) is adequate to ensure operation of the metal detector only in cases of actual need. I However, it should be noted that if a person remains trapped owing to an uncommon metal mass being carried thereby, it will always be possible to release him/her immediately upon identification. It should be further noted that, for a correct operation of the device, it is necessary that the persons entering the enclosed area follow the path B, namely that the door 2 only rotates in the direction A.

To prevent the door from rotating in the opposite direction, conventional ratchet mechanism may be used. Advantageously, said ratchet mechanism will include a undirectional coupling, e.g. a free-wheel mechanism 46 intervening between the sleeve 27 and bushing 29.

The detector utilized herein is shown in Figure 4. It comprises a quartz squarer-oscillator assembly 47 the frequency whereof is brought to a predetermined value by means of a divider circuit 48. The reference numerai 49 denotes a controlled oscillator, inciuding a pick up coil 50 and tuning capacitor 51, which is voltage controlled by a so-called varicap diode 52. The pick up coil 50 will be positioned at a location such-as to be influenced by the metal object carrying person while following the path B. The output signal from the oscillator 49, being squared by the squarer 53, has the same frequency as the ouput signal from the divider 48. both signals are passed to the input of a phase comparator 54, which may be so-called flip-flop circuit.The pulsating signal from the comparator 54 is passed to an integrating low pass filter 55 which integrates said signal and converts it into a DC voltage proportional to the phase difference between the signals from the oscillators 47,49.

This voltage, when applied to the varicap diode 52, compensates for any frequency variation of the controlled oscillator 49.

The DC voltage is then applied to an integrator 56. which, together with the filter 55, has the dual function of eliminating high frequency residuals and slowing down the circuit in order to minimize noise influence.

The output signal from the integrator 56 is thus subjected to double derivation and amplification in the derivators 57, 58 and operational amplifiers 59, 60. The derivations eliminate the low frequency signals generated by the oscillator drift.

This reflects in practice in limiting the pass-band of the amplifiers. The output voltage from the amplifier 60 is applied to a threshold circuit or trigger 61 through a setting device 62 which stabilizes the operating threshold. The trigger 61, through an optical insulator 63, is connected to an amplifier 64 which is enabled to energize a relay, 65 the contacts whereof control the energization of the winding -44 and accordingly the operation of the block 39, 40.

The optical insulator 63 serves to block any noise generated by the reduction gear 9 or by the solenoid 41,44. It may comprise a coupling between a light-emitting diode and a phototransistor.

The detector operates as follows. As a metal object moves past the field of influence of the pick up coil 50, there occurs a variation in the voltage supplied by the controlled oscillator, and consequently also in the output voltage of the comparator 54. If the metal object is of a size such that the output voltager from the comparator 54 exceeds a predetermined value, the trigger 61 becomes operative. The trigger output voltage closes the contacts of the relay 65 thus causing the winding 44 to become energized and the block 39, 40 to be actuated. To reset the trigger 61, provision is made for a manually operated button. The trigger operation may be monitored by a light-emitting diode. Furthermore, the oscillatore latching may be monitored by an instrument derived from the output of the filter 55.

The detector is susceptible to many modifications and variations, depending on the device construction, which additionally to contemplating a revolving type of door, may comprise a pair of sliding doors spaced apart such as to enclose a space corresponding to the cited space 8.

Claims (8)

1. A device for preventing weapon carrying persons from entering an enclosed or restricted area, characterized in that it comprises a cylindrical housing located at the entrance the enclosed area and provided with an entrance opening and an exit opening effective to place the enclosed area into communication with the outside environment, within said housing there being journalled a door of the radial vane type, said radial vanes defining cylindrical sector spaces, said housing and said door being made of a bulletproof material, and in that a metal object detector is provided for detecting the presence of metal objects carried on or by a person being momentarily located in an enclosed space of said housing and controlling an actuating solenoid of a lock operative to block said door against rotation and hold said metal object carrying person confined within said enclosed space.

2. A device according to Claim 1, characterized in that said lock comprises a sleeve coaxial with the rotation axis of said door and rotatively rigid therewith, whereto a ring made of a ferromagnetic material is coupled pivotally, said ring being axially movable and provided with a peripheral tooth formation, and that facing said ring there is arranged a stationary disc accomodating an energization winding provided with a peripheral tooth formation facing said tooth formation of said ring, said winding being operationally linked to said metal detector such as to cause said ring to be pulled and said tooth formations mesh engaged upon energization thereof.

3. A device according to Claim 2, characterized in that said disc is rigid with the output shaft of a reduction gear for actuating said door when said tooth formations mesh together.

4. A device according to Claim 2, characterized in that said sleeve is carried pivotally on said output shaft with the interposition of a unidirectional coupling.

5. A device according to Claim 1, characterized in that said metal object detector comprises a constant-frequency oscillator, a second controlled oscillator comprising a pick up coil positioned at a location suitable to become influenced by a metal object carried on or by a person, the output signals from said oscillators being applied to a phase comparator, the output signal wherefrom is passed through an integrating filter to a threshold circuit operative to energize a control relay for the solenoid actuating said lock.

6. A device according to Claim 5, characterized in that said controlled oscillator is voltage controlled by a varicap diode for accomodating frequency variations of said oscillator, and in that the output signal from said phase comparator is applied to said varicap diode.

7. A device according to Claim 6, characterized in that said output signal from said integrating filter is further integrate, derivated and amplified and then passed to said threshold circuit.

8. A device for preventing weapon carrying persons from entering an enclosed or restricted area, substantially as herein described with reference to the accompanying drawings.