AUTOMATIC ADMITTANCE CONTROL SERVOSYSTEM COUPLED TO A METAL DETECTOR

Abstract: The automatic admittance control servosystem comprises a box consisting of two opposite walls and at least two interlocked doors, said walls and doors defining a chamber acting as a filter. The servosystem is provided on the upper part with an oleodynamic actuator having at least two cylinders which are driven by an electronic control system and are able to put one door near the second door in order to ascertain the eventual presence of metal things which have been detected by the metal detector. In such a case the doors remain locked in the closed position, the metal things lying therebetween, and an alarm signal is generated causing the intervention of the guardians. On the contrary, when there is no metal thing between the doors close to each other, the latter open automatically again up to their rest position.

Description: AUTOMATIC ADMITTANCE CONTROL SERVOSYSTEM COUPLED TO A METAL DETECTOR The present invention relates to an automatic admittance control servosystem with interlocked doors, the outer door being provided with a metal detector. In the last years, in the light of the more and more frequent robberies in particular to banks, post offices and jewelleries, the latter and other valuables deposits supplied special doors coupled to metal detectors in order to prevent the admittance of armed people. In view of the fact that the provision of a metal detector in a single door, even if armoured, does not provide satisfactory results because also armed people can go across the door together with non-armed people once the door is open, the installation of complicated closing systems has been resorted to. Examples of such systems are following: two subsequent interlocked doors, i.e. alternate opening doors, so that the second door can be crossed only after the closure of the first door revolving door systems in which the doors are rotating about a vertical axis placed in the middle of the entrance span and inner door systems, the latter two systems allowing the admittance by a controlled actuation. Such an actuation needed hitherto at least a guardian surveying the people coming in and evaluating the effective danger thereof after being alerted by the eventual metal detector and eventually providing an alarm signal or restoring a situation of pre-alarm. In particular, the guardian has to inform people coming in, once the metal detector comes into operation, that they have to deposit everything may hamper the transit before trying again to go across the door. This can be done, as it is the case, by means of a recorded warning signal. The guardian has to check that after an alarm an ill- intentioned person coming in the box, for example in the space between said two interlocked doors after the metal detector, does not leave any weapon within said space that can be picked up by the same person or by his accomplices after the next transit through the metal detector, this time without alarm, thus baffling the vigilance. It is an object of the invention to provide an admittance system that under normal operating conditions does not need a guardian. The admittance system as claimed consists of a transit box, with at least two doors, which is coupled to a metal detector and is provided with means for sweeping the space between the two doors in order to automatically check the presence of weapons therein. The weapons could be laid down by an ill-intentioned person in order to commit a robbery later on when the gangster or his accomplices crossing the metal detector again, this time without weapons, have free admittance. Among the advantages of the present invention it is to mention that the life of the guardian is not in danger and the intervention of the same is reduced only to the case of need. Furthermore the system is reliable and its cost is only a little higher than that of systems already in operation. These and other advantages and features of the invention will be more readily apparent from the following description of some embodiment taken in connection with the accompanying drawings, in which: Fig. 1 is an elevational front view of a box which is part of an admittance system according to a first embodiment of the invention, the doors of the box being locked; Fig. 2 is a section along the line A-A of Fig. 1; Fig. 3 is a top plan view of an oleodynamic actuator and the driving means of the admittance system according to the first embodiment of the invention; Figs. 4a to 4e are schematic top plan views showing the operation of the admittance system of the preceding figures in case of a transit without alarm; Figs. 5a to 5e are views like those of Figs. 4a to 4e but in case of a transit with alarm; Figs. 6a to 6f are views like those of Figs. 5a to 5e but relative to a second embodiment of the invention; and Figs. 7a to 7e are views like those of Figs. 5a to 5e, but concerning the operation of a third embodiment of the invention. Reference is first made to Figs. 1 and 2 wherein a transit box, generally indicated as 1, and constructed with standard section and sheet preferably of stainless steel and having the form of a parallelepiped is depicted. Of course, in order to allow the transit through the parallelepiped box two opposite walls are missing. There are two doors shown in Fig. 2 and designated by 2A and 2B with full lines in the locked position, by 2A' and 2B 1 with dashed lines in the closed position and by 2A" and 2B" with dashed lines in the open position (it is self evident that the latter position is never taken in practice because one of the two doors must be always closed). Both doors are hinged on vertical, parallel axis which are close to each other and are placed near the inner corner of the shorter wall 3 of the box. The free ends of the doors revolve skimming over the opposite wall 4 of the box along a central arc of the whole angular elongation of 180°. A metal detector 6 is provided near the entrance 5. In the box 1, above the transit space there is a casing 7 comprising a pair of oleodynamic actuators 8A and 8B, an electropump 9 and an oil reservoir 10 supported by suitable fittings. Each oleodynamic actuator is mounted so as to rotate on a support 11A and 11B, respectively, and is provided with oil feeding hoses. The piston rod of each oleodynamic actuator 8A and 8B is linked at its free end with a lever 12A and 12B, respectively, to rotate the doors. The operation of the actuators is controlled by means of electrovalves of an electronic system (not shown). Under the control of the latter the doors can rotate from a closed position to the locked position, in which they are placed side by side (Figs. 1 and 2). The operation of the first embodiment of the invention is now described with reference to Figs. 4a to 4e in the case of a transit without alarm, and to Figs. 5a to 5e in the case of a transit with alarm. Who sets about going across the door finds the outer door 2A near the outer end of the wall 4 (Fig. 4a) in the non-locked position. Thus he opens the door manually (Fig. 4b) acting against the oil contained in the cylinder of the actuator 8A and enters the space cotrolled after having gone beyond the metal detector 6. The man does not have things that cause an alarm signal to be activated and therefore once the door 2A is closed and locked by means of a known locking device not shown (Fig. 4c), the locking device of the door 2B opens and the man pushing the door can be admitted to the protected room. The door 2B returns automatically to the closed position (Fig. 4e). In the case of Figs. 5a to 5e the man entering the controlled space of the box has something that causes the alarm signal to be activated by the metal detector and therefore the door 2A does not close and the door 2B does not open (Fig. 5b). By means of an interphone not shown the man receives the instruction of going out and laying down the metal thing that does not allow him to go across the door (Fig. 5c). The door 2A then closes and the electronic system provides a control signal to the actuators which rotate the doors 2A and 2B to each other to the extent in which they are parallel and touch each other (Fig. 5d) . In case no thing is laid down in the space between the doors, the alarm conditions leave off and the doors return to their normal position ready for the next admittance. In case the doors sweeping the space between each other run into things left in said space, an alarm signal is activated by the electronic control system and the doors remain locked. Only in the latter case the intervention of the guardian is needed. In Figs. 6a to 6f, in which because of their evidence the reference numerals are left out as well as in the following figures, the operation of a second embodiment of the admittance system according to the present invention is depicted. The operation without automatic alarm is that already known for the illustrated arrangement of doors, i.e. two parallel doors including a space between two opposite walls of a box. In case the metal detector senses a metal thing (Fig. 6b) a recorded instruction invites the person entered the space between the doors to go out (Fig. 6c). The entrance door closes (Fig. 6d) and afterwards the two doors, that in this embodiment are mounted on pairs of upper and lower guides, move translating to each other under the control of oleodynamic cylinders driven by an electronic control system, thus sweeping the space up to their coming into contact (Fig. 6e). In case the checked person leaves in said space the thing that caused the alarm signal to be activated, the two doors running into it during their movement of translation are locked and cannot reach the end of the stroke. In such a case the intervention of a guardian is requested so that the doors are allowed to return to their closed position (Fig. 6f). The provision of an actuator, which is here not illustrated into detail, will be easy to the skilled in the art by means of the same devices used in the first embodiment. In Figs. 7a to 7e the operation of a third embodiment of the admittance system according to the present invention is depicted. It generally consists of a revolving door box provided with a double actuation system of the type already described for the first embodiment. In case a metal thing is detected (Fig. 7b), the revolving door rotates by a quarter of turn after the person having been invited to go out (Fig. 7c). Then the four wings close in pairs like scissors sweeping the checked space (Fig. 7d) . The normal condition will be restored (Fig. 7e) either automatically in case the doors do not run into any thing or manually in case a pair of wings run into the metal thing that caused the alarm signal to be activated.

Claims: CLAIMS 1. Automatic admittance control servosystem coupled to a metal detector comprising a transit box consisting of two opposite walls and at least two interlocked doors, the walls and the doors defining a space therebetween acting as a filter intended to be occupied by people before their entering the protected room, characterized in that above the box an oleodynamic actuator is provided having at least two cylinders that under the control of an electronic control system are able to put one door near the second door in order to sweep the space therebetween after a suitable delay with respect to the detection of a metal thing in the box, the electronic control system providing either a signal to open the doors up to their rest position or an alarm signal and a control signal to maintain the doors in the closed position in case no thing remains between the two doors or a metal thing sensed by the metal detector is lying therebetween, respectively. 2. Admittance system according to claim 1, wherein the doors are hinged to rotate about two vertical, parallel axis close to each other and define in the rest position a space therebetween having the form of a cIrcular sector. 3. Admittance system according to claim 1, wherein the doors are hinged to rotate about two vertical, parallel axis which are diagonally opposite to each other in a space between the two doors having substantially the form of a square, the doors being able to move translating to each other under the control of the oleodynamic actuator on pairs of guides which are provided above and below the box and are parallel to the walls thereof. 4. Admittance system according to claim 1, wherein the door is of the revolving type and consists of four wings that can be closed in pairs in order to sweep two spaces each having a form of circular sector.

Inventors: ORSINI CARLO, ORSINI DANIELE, ORSINI GIORGIO, ORSINI, CARLO, ORSINI, DANIELE, ORSINI, GIORGIO
Applicants: BLINDART ORSINI SPA, BLINDART ORSINI S.P.A.
Application year: 1985
Main classification: G08B15
IPC codes: E05G5, G08B15