GB1599883A - Rail clip assemblies alarm control circuits for buildings - Google Patents

Description

(54) IMPROVEMENTS IN ALARM CONTROL CIRCUS FOR BUILDINGS (71) We, G. LOWE (OLDHAM) LIMITED, of 173-177 Lees Road, Oldham, County of Lancaster, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to improvements in alarm control circuits for the protection of premises against unauthorised entry, in particular of the type of circuits which can only be operated when all the entry detection elements of the circuit are in the correct condition.

Simple circuits for this purpose have been proposed such as entry detection elements for door and window operated contacts or pressure pads, or more sophisticated devices such as ultrasonic or microwave or infra-red intruder detection units, operating singly or collectively.

One weakness of present alarm circuit systems lies in their provision of timed exit routes and their vulnerability - from the instant of priming the alarm circuits up to closure and locking of the exit door - to an unauthorised entry and cancellation of the alarm system by such unauthorised entrants, during the timed exit period.

A further weakness of present alarm circuit systems lies in the possibility of an operator leaving premises in which not all the entry detection devices have been set in the correct condition, thus leading to an eventual alarm being given which - if it is of the "silent" type - could give a fake and unnecessary alarm at a police station or security service establishment, without the alarm system operator being aware of the error until it is too late to rectify the mistake.

An even greater weakness of present alarm circuit systems is in the allowing of authorised personnel to leave the supposedly protected premises without having primed the alarm system at all.

The object of the invention is to overcome these weaknesses by only allowing the locking instrument - usually a conventional key to be withdrawn from the exit door of the premises when all the unauthorised entry detection devices and circuits have been correctly set to an "on-guard" condition.

An alarm control unit has been proposed for guarding a device such as a safe -- Comprising a key-operated lock with an electro-magnet catch to prevent its rotation from an "offguard" position to an "on-guard" position, and signalling device such as lamps to indicate the condition of the protected device before rotation of the key from an "off-guard" to an "on-guard" position, together with means for removing the catch from the lock if the protected device is in a correct condition for extending the alarm circuit. The difficulties in applying such apparatus to the guarding of premises has been already referred to.

An alarm control circuit for buildings set out in two stages comprises signalling devices in the building which can be set to "on-guard" position in the first stage, a locking device operable to lock the door after all the personnel have left and an outer exit door of the building is closed by an operator on the outside, and an electrically controlled means to allow the locking device to be operated in the second stage provided all the signalling devices are set to the "on-guard" position.

The invention will be described with reference to the accompanying drawings which example ways in which the intended objectives may be achieved: Fig. 1 is a diagrammatic perspective view of a control unit operated by a relay; Fig. 2 is a diagrammatic perspective view of a control unit operated by a solenoid; Fig. 3 is a vertical sectional view showing alternative solenoid mounting and alternative contact mountings, to show that these may be mounted on the door or moving part of the exit aperture, or on the door frame.

Fig. 1 shows a compartment 1 into which the bolt (not shown) of the lock is moved in order to secure the outer door, movement of the bolt within the compartment being only possible provided a pivoted armature 2 is not preventing entry of the bolt, the armature 2 being moved from point A to point B, so as to allow entry, by the energising of a relay coil 5. Entry of the bolt within compartment 1 causes it to connect with a push rod 3 which in turn operates the contacts 4. Although normally open contacts 4 are shown it will be appreciated that normally open and/or normally closed contacts may be caused to close and/or open, as a result of entry of the bolt within the compartment, 1, such contacts being used in alarm circuits and/or indication circuits and also to de-energise the relay coil 5 to conserve power or prevent over-heating.

Similar comments apply to Fig. 2 in which the relay coil has been replaced by the solenoid coil 6 and the armature has been replaced by solenoid plunger 7 which must be moved from position A to position B to allow full bolt entry into the compartment 1.

Fig. 3 also shows that the solenoid having plungers 7, in mounting position A will when de-energised move its plunger into slot 8 to prevent movement of the bolt into the compartment la on the door frame but that once the bolt has been allowed to enter the compartment on the door frame a de-energising of the solenoid coil will allow the solenoid plunger to enter the slot 8a thus maintaining the bolt in the locked position such a feature using a slot 8a may not always be required; Fig. 3 also shows alternative contact position and it will be appreciated that to give satisfactory operation the preferably operate in the late stage of the bolt movement.

The Figure illustrates that the solenoids which release the bolt and thus allow the bolt to enter into the compartment la (similar to that referred to in Figs. 1 and 2), mounted in the door, moves the plungers 7, 7a from points B to points A to release the bolt 9.

Fig. 3 also shows that the solenoid having the plunger 7 or 7a in each of the two compartments 1, la when in the mounting position A will when energised move to position B. The solenoid coils 6 simultaneously occupy the compartment 1, la and when energised the plungers move to the points which releases the bolt 9 to allow the bolt to move from compartment 1 on the door frame into the compartment la on the door. When the solenoid coils 6, 6a are energised to lift the solenoid plungers 7, 7a respectively in the compartments 1, la the end of the bolt is freed to move into the compartment la and the de-energisation of the solenoid allows the plungers 7, 7a to move from the points B to the points A.

The drawing also shows that on deenergisation of the solenoid the plunger 7a moves in the slot 8, and plunger 7 moves in the slot 8a thereby maintaining the bolt in the locked position.

The bolt referred to in the comments on Figs. 1 and 2 will normally be operated by the turning of a key and the position of the relay armature or the solenoid plunger will be such that movement of the lock bolt to allow the key to be withdrawn, will be prevented unless the relay coil or the solenoid coil has been energised to cause their associated armature to move from position A to position B.

Contacts 10a operated by the lock bolt 9 may be used in a sequence combination with contacts operated by movement of the door such that personnel exit from the premises must be followed by door closure and door locking in that order, whilst personnel entry must be preceded by door unlocking and door opening in that order, to prevent the giving of an alarm. The purpose of such operating sequence is to guard against unauthorised entry by forcing of the doors when operating the door contact prior to the operating of the lock bolt contact could be used to give an alarm.

It will be seen that the invention described obviates the need for timed exit and timed entry devices, because closure of the door and its subsequent locking - either alone or in conjunction with other circuit completion arrangements (such as the external push button already referred to) - may be used to set or prime the "on-guard" circuits, and opening of the door by authorised means, possibly in a sequence involving door-operated contacts or other devices, may be used to disarm or de-prime the "on-guard" circuits.

However, in one form of application of the invention, door closure and locking initiates a fairly short time period delay during which immediate pre-entry even by authorised means (such as the use of a key stolen by a would be intruder) is prevented, the time period being so chosen as to allow the possibility of raising an alarm immediately should it be necessary to do so, before the premises could be entered by unauthorised personnel without the risk of being caught and detained.

Alternatively, entry could be allowed in the period but a signal is given to operate the alarm in that time period, either locally and/or to a remote security establishment.

An essential feature of the invention described, is that the devices associated with lock bolt movement prevention, i.e. the relay and the solenoid of Figs. 1 and 2, are used in a manner so as to "fail Safe" in which supply failure or coil open-circuiting etc, result in the door being prevented from being locked until the cause of non-locking has been corrected.

WHAT WE CLAIM IS: 1. An alarm control circuit for buildings set out in two stages, comprising signalling devices in the building which can be set to "on-guard" positions in the first stage, a locking device operable to lock the door after all the personnel have left and an outer exit door of the building is closed by an operator on the outside, and an electrically controlled means to allow the locking device to be operated in the second stage provided all the signalling devices are set to the "on-guard" position.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. in turn operates the contacts 4. Although normally open contacts 4 are shown it will be appreciated that normally open and/or normally closed contacts may be caused to close and/or open, as a result of entry of the bolt within the compartment, 1, such contacts being used in alarm circuits and/or indication circuits and also to de-energise the relay coil 5 to conserve power or prevent over-heating. Similar comments apply to Fig. 2 in which the relay coil has been replaced by the solenoid coil 6 and the armature has been replaced by solenoid plunger 7 which must be moved from position A to position B to allow full bolt entry into the compartment 1. Fig. 3 also shows that the solenoid having plungers 7, in mounting position A will when de-energised move its plunger into slot 8 to prevent movement of the bolt into the compartment la on the door frame but that once the bolt has been allowed to enter the compartment on the door frame a de-energising of the solenoid coil will allow the solenoid plunger to enter the slot 8a thus maintaining the bolt in the locked position such a feature using a slot 8a may not always be required; Fig. 3 also shows alternative contact position and it will be appreciated that to give satisfactory operation the preferably operate in the late stage of the bolt movement. The Figure illustrates that the solenoids which release the bolt and thus allow the bolt to enter into the compartment la (similar to that referred to in Figs. 1 and 2), mounted in the door, moves the plungers 7, 7a from points B to points A to release the bolt 9. Fig. 3 also shows that the solenoid having the plunger 7 or 7a in each of the two compartments 1, la when in the mounting position A will when energised move to position B. The solenoid coils 6 simultaneously occupy the compartment 1, la and when energised the plungers move to the points which releases the bolt 9 to allow the bolt to move from compartment 1 on the door frame into the compartment la on the door. When the solenoid coils 6, 6a are energised to lift the solenoid plungers 7, 7a respectively in the compartments 1, la the end of the bolt is freed to move into the compartment la and the de-energisation of the solenoid allows the plungers 7, 7a to move from the points B to the points A. The drawing also shows that on deenergisation of the solenoid the plunger 7a moves in the slot 8, and plunger 7 moves in the slot 8a thereby maintaining the bolt in the locked position. The bolt referred to in the comments on Figs. 1 and 2 will normally be operated by the turning of a key and the position of the relay armature or the solenoid plunger will be such that movement of the lock bolt to allow the key to be withdrawn, will be prevented unless the relay coil or the solenoid coil has been energised to cause their associated armature to move from position A to position B. Contacts 10a operated by the lock bolt 9 may be used in a sequence combination with contacts operated by movement of the door such that personnel exit from the premises must be followed by door closure and door locking in that order, whilst personnel entry must be preceded by door unlocking and door opening in that order, to prevent the giving of an alarm. The purpose of such operating sequence is to guard against unauthorised entry by forcing of the doors when operating the door contact prior to the operating of the lock bolt contact could be used to give an alarm. It will be seen that the invention described obviates the need for timed exit and timed entry devices, because closure of the door and its subsequent locking - either alone or in conjunction with other circuit completion arrangements (such as the external push button already referred to) - may be used to set or prime the "on-guard" circuits, and opening of the door by authorised means, possibly in a sequence involving door-operated contacts or other devices, may be used to disarm or de-prime the "on-guard" circuits. However, in one form of application of the invention, door closure and locking initiates a fairly short time period delay during which immediate pre-entry even by authorised means (such as the use of a key stolen by a would be intruder) is prevented, the time period being so chosen as to allow the possibility of raising an alarm immediately should it be necessary to do so, before the premises could be entered by unauthorised personnel without the risk of being caught and detained. Alternatively, entry could be allowed in the period but a signal is given to operate the alarm in that time period, either locally and/or to a remote security establishment. An essential feature of the invention described, is that the devices associated with lock bolt movement prevention, i.e. the relay and the solenoid of Figs. 1 and 2, are used in a manner so as to "fail Safe" in which supply failure or coil open-circuiting etc, result in the door being prevented from being locked until the cause of non-locking has been corrected. WHAT WE CLAIM IS:

1. An alarm control circuit for buildings set out in two stages, comprising signalling devices in the building which can be set to "on-guard" positions in the first stage, a locking device operable to lock the door after all the personnel have left and an outer exit door of the building is closed by an operator on the outside, and an electrically controlled means to allow the locking device to be operated in the second stage provided all the signalling devices are set to the "on-guard" position.

2. An alarm control circuit as in

Claim 1 in which the second stage electrically controlled means is a relay which is energised when the signalling device is set in the "onguard" position to move a plate to allow a bolt to lock the door of the building.

3. An alarm control circuit as in Claim 1 in which the electrically controlled means is a solenoid which is energised when the signalling device is set in the "on-guard" position to move an armature to allow the bolt to lock the door of the building.

4. An alarm control circuit as in Claims 1 or 2 in which the solenoid is mounted on the door frame or on the door.

5. An alarm control circuit as in Claims 1 to 4 in which the operation of setting of the alarm is carried out in sequence and the cancelling of the setting is carried out in the reverse sequence.

6. An alarm control circuit as in Claims 1 to 5 in combination with a time delay circuit to prevent the locking device from being reoperated for a predetermined interval of time after the device has been set

7. An alarm control circuit as in Claims 1 to 5 in which the locking device can be operated to allow entry immediately after locking but a time delay circuit only deenergises the device after a predetermined interval of time.

8. An alarm control circuit as in Claims 1 to 7 in which a key punched card or magnetically coded device act as the locking device.

9. An alarm control circuit for premises substantially as described with reference to Fig. 1 or 2 or Fig. 3 of the accompanying drawings.