US3677370A - Elevator alarm system - Google Patents

Abstract

An alarm system is connected to conventional elevator control apparatus. If the inside elevator doors are opened between floors, the conventional switch responsive to such opening will actuate timing means in the alarm system. If the inner doors remain open for a predetermined time interval, a main alarm switch will become operative (1) to signal a remote control station, (2) to energize a local portable alarm, and (3) to deenergize the main elevator drive motor until the main alarm switch is reset.

Description

United States Patent Devine [45] July 18, 1972 [s41 ELEVATOR ALARM SYSTEM 3,531,793 9/1970 Shottenfeld ..340/274 x [72] Inventor: new Devin. Chicago, m 3,568,199 3/1971 Hartness ..343/225 [73] Assign: m Sm m FOREIGN PATENTS OR APPLICATIONS g [21] Appl. No.: 65,110 Primary xaminer.|ohn W. Caldwell Assistant Examiner-Kenneth N. Leimer 52 us. c1. 187/31, 340/19, 340/274, and Gemma" 340/419 57 Hm [51] Int. B66b3/00 1 A CT [58] Field of Search ..187/29 R, 31, 48, 50; 340/19, An alarm system is nn d o n n i nal elevator con- 340 21 2 3 l 19 274 trol apparatus. 1! the inside elevator doors are opened between floors, the conventional switch responsive tosuch opening will [56 I Rel-mum CM actuate timing means in the alarm system. If the inner doors remain open for a predetermined time interval, a main alarm UNITED STATES PATENTS switch will become operative (1) to signal a remote control station, (2) to energize a local portable alarm, and (3) to 2,419,978 5/1947 f 343/225 X deenergize the main elevator drive motor until the main alarm 2,994,025 7/1961 Mitchell ..l87/29 R X switch is reset 2,994,073 7/1961 Pelovitz.... .....340/2l3.l 3,461,422 8/1969 Hansen ..l87/29 R X 5 Claims, 1 Drawing figure coNTROL STATIpN Patented July 18, 1972 3,677,370

CONTROL sTATIQN //v VENTOE Y y Edward Dvm MYW a 5 ELEVATOR ALARM SYSTEM FIELD OF THE INVENTION This invention relates to a novel elevator alarm system for use with conventional elevator control equipment.

BACKGROUND OF THE INVENTION Police records indicate that many robberies and assaults are commited on elevators, particularly in apartment buildings in low income areas. Typically the inner elevator door As used herein, the term inner elevator door" refers to the door or doors which form part of the elevator cab and move with it, and the term outer elevator door" refers to the door generally located in a hallway which opens to the elevator shaft and which is aligned with the inner elevator doors when the cab is on the respective floor.) is forced open between floors by one of the passengers, conventionally causing the elevator to stop between floors, and the other passenger is robbed or assaulted while the inner elevator door remains open. Occasionally the inner elevator doors will be forced open between floors by a passenger who will also release the latch to the outer elevator door allowing an accomplice on the outside to climb on top of the elevator cab. Generally various elevator controls are located on top of the cab and the party riding on top of the cab can extort money from elevator passengers by preventing the elevator from moving until payment is made.

It is not uncommon for children in the elevator to open the inner door in order to stop the elevator momentarily. However, under such circumstances it is typical for the child to open the door for a relatively short time, typically for only 1 to 5 seconds. On the other hand, if the inner elevator door is being opened for purposes of robbery or assault, the door will generally remain open for more than seconds. Therefore, it is an object of the invention to provide an alarm system which is actuated after the inner elevator door has been opened for more than a predetermined period of time, which in the illustrative embodiment is at least 10 seconds.

BRIEF DESCRIPTION OF THE INVENTION In accordance with the present invention there is provided an elevator alarm system for use with an elevator control system having switching means responsive to opening of the inner elevator door between floors and having a main power switch. The alarm system comprises timer means operative in response to actuation of the switching means. Means controlled by the timer means are provided and are operable after 1 a predetermined time period to actuate a main alarm switch.

BRIEF DESCRIPTION OF THE DRAWING The drawing is a schematic circuit diagram of an elevator alarm system in conjunction with a conventional elevator control system, in accordance with the principles of the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT Referring to the drawing, the elevator 10 is driven by motor 12, with the elevator system being controlled by a conventional control system 14. The control system comprises a main power relay 16 for controlling the power to motor 12 and a conventional relay winding 18 which is normally energized but becomes deenergized only when the inner elevator door is opened between floors. An example of such a relay is the GW relay commonly used in the control system for Otis elevators.

The elevator alarm system of the present invention is connected to elevator control system 14 by connecting a relay winding 20 of normally open relay 22 in parallel with winding 18 so that relay 22 will be deactuated in response to the opening of the inner elevator door between floors. Connected in series with the arm 24 of relay 22 is a timer 26 having an output relay 28 which is energized in response to an output signal from timer 26 after a preset time period, preferably between 5 and 30 seconds from initial actuation of the timer resulting from deactuation of relay 22. In the illustrative embodiment the timer is set to provide an output signal after 10 seconds have elapsed. The timer circuit is energized by a 1 l0 volt AC source 30.

The arm 32 of relay 28 is connected in series with the winding 34 of a main alarm relay 36 having ganged arms 38, 40, 42 and 44. It can be seen that winding 34 is normally energized via line 46, arm 44, winding 34, line 48, arm 32 and line 50 but when relay 28 is activated by timer 26 to open the contacts, winding 34 will be deenergized to open the contacts associated with arms 38, 40, 42 and 44.

When winding 34 is energized, arm 38 is connected in series with winding 16 to permit motor 12 to operate unless operation of the motor is discontinued for some other reason, arm 40 is connected to maintain a closed circuit to a remote control station 52 at which an alarm is actuated when the circuit is opened, arm 42 normally opens the circuit to local alarm bell 54 and arm 44 provides a holding circuit for winding 34 once the main alarm relay 36 has been reset by means of reset switch 60. g

Once winding 34 is deenergized, winding 16 will be open circuited thereby discontinuing power to motor 12 and preventing the elevator from operating until the alarm system is reset. Further, arm 40 will cause an open circuit to remote control station 52, thereby activating the alarm there. Additionally, arm 42 will close the circuit to bell 54, thereby actuating the local alarm and arm 44 will open the circuit to winding 34, preventing the winding from being energized until it is positively reset by means of reset switch 60.

It is important that reset switch 60 be out of the reach of the person in the elevator causing the alarm to be activated and for that reason reset switch 60 is, remotely located from the inside of the elevator. In large buildings where reset switch 60 is located near the top of the building, it is advisable to have the ability to operate the switch from the first floor of the building, preferably by means of radio transmitter 62 which transmits a signal to a receiver at the reset switch location to cause energization of the reset switch in a conventional radio-controlled manner. 1

It can be seen that when the inner door of an elevator is opened for more than 10 seconds, an alarm at a remote control station (for example the local police station) will be actuated, a local audible alarm will be actuated, and the elevator will be immobile until a positive reset action is taken. In this manner, the person opening the inner elevator door for more than 10 seconds can be easily apprehended.

Although an illustrative embodiment of the invention has been shown and described, it is to be understood that various modifications and substitutions may be made by those skilled in the art without departing from the spirit and scope of the present invention.

What is claimed is:

I. In an elevator control system having switching means responsive to opening of the inner elevator door between floors, the improvement comprising, in combination: timer means operative in response to actuation of said switching means; means controlled by said timer means and operable after a predetermined time period to actuate a main alarm switch, said main alarm switch having means for signalling a remote control station and means for deenergizing the elevator drive motor notwithstanding closing of the inner elevator door; and reset means remotely located from the insideof the elevator for resetting said main alarm switch.

2. An elevator alarm system as described in claim 1, in which said timer means is connected in circuit with timer switching means and said timer switching means is connected in parallel with said first-mentioned switching means; said main alarm switch comprising a normally energized relay winding operably connected for deenergization in response to said timer controlled means.

3. An elevator alarm system as described in claim 1, wherein said timer means is set to cause actuation of said main alarm switch only after said predetermined time period of at least seconds has elapsed.

4. An elevator alarm system as described in claim 1, including radio transmitter means for actuating said reset means.

5. In an elevator control system having switching means responsive to opening of the inner elevator door between floors, the improvement comprising, in combination: a first relay winding connected to said switching means; timer means operable in response to said first relay winding; means for setting said timer means to provide an output signal after a predetermined time period; a main alarm relay having four ganged arms; means for normally energizing said main alarm relay winding; means coupling said timer means to said main alarm relay winding whereby said main alarm relay winding is deenergized in response to said output signal; said main alarm relay having a first arm operable when said winding is deenergized to prevent operation of the elevator drive motor, a second arm operable when said winding is deenergized to signal a remote control station, a third arm operable when said winding is deenergized to actuate a local audible alarm, and a fourth arm operable when said winding is deenergized to prevent said alarm relay from being reactuated until it is positively reset; and means remotely located from the inside of the elevator for resetting the main alarm relay.

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Claims (5)

1. In an elevator control system having switching means responsive to opening of the inner elevator door between floors, the improvement comprising, in combination: timer means operative in response to actuation of said switching means; means controlled by said timer means and operable after a predetermined time period to actuate a main alarm switch, said main alarm switch having means for signalling a remote control station and means for deenergizing the elevator drive motor notwithstanding closing of the inner elevator door; and reset means remotely located from the inside of the elevator for resetting said main alarm switch.

2. An elevator alarm system as described in claim 1, in which said timer means is connected in circuit with timer switching means and said timer switching means is connected in parallel with said first-mentioned switching means; said main alarm switch comprising a normally energized relay winding operably connected for deenergization in response to said timer controlled means.

3. An elevator alarm system as described in claim 1, wherein said timer means is set to cause actuation of said main alarm switch only after said predetermined time period of at least 10 seconds has elapsed.

4. An elevator alarm system as described in claim 1, including radio transmitter means for actuating said reset means.

5. In an elevator control system having switching means responsive to opening of the inner elevator door between floors, the improvement comprising, in combination: a first relay winding connected to said switching means; timer means operable in response to said first relay winding; means for setting said timer means to provide an output signal after a predetermined time period; a main alarm relay having four ganged arms; means for normally energizing said main alarm relay winding; means coupling said timer means to said main alarm relay winding whereby said main alarm relay winding is deenergized in response to said output signal; said main alarm relay having a first arm operable when said winding is deenergized to prevent operation of the elevator drive motor, a second arm operable when said winding is deenergized to signal a remote control station, a third arm operable when said winding is deenergized to actuate a local audible alarm, and a fourth arm operable when said winding is deenergized to prevent said alarm relay from being reactuated until it is positively reset; and means remotely located from the inside of the elevator for resetting the main alarm relay.

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