US3835461A

US3835461A - Tamperproof alarm switch

Info

Publication number: US3835461A
Application number: US00289783A
Authority: US
Inventors: J Nelson
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-06-18
Filing date: 1963-06-18
Publication date: 1974-09-10
Anticipated expiration: 1991-09-10

Abstract

1. An alarm system for a normally closed security room having a movable room closure providing access thereto, which comprises, A. A NORMALLY CLOSED HOUSING WITHIN THE SECURITY ROOM HAVING A MOVABLE HOUSING COVER PROVIDING ACCESS THERETO, B. A FIRST SWITCH IN THE HOUSING, A FIRST REMOTE INDICATOR AND ELECTRICAL CONNECTIONS THEREBETWEEN, C. A SECOND SWITCH IN THE HOUSING, A SECOND REMOTE INDICATOR AND ELECTRICAL CONNECTIONS THEREBETWEEN, D. SAID FIRST SWITCH HAVING A CONTACT ARM WHICH IS OPERABLE BY MOVEMENT OF THE ROOM CLOSURE TO INDEPENDENTLY ENERGIZE THE FIRST INDICATOR, E. SAID SECOND SWITCH HAVING A CONTACT ARM CONNECTED TO THE HOUSING COVER AND OPERABLE BY MOVEMENT OF THE HOUSING COVER TO ENERGIZE THE SECOND INDICATOR, F. A THIRD SWITCH IN THE HOUSING HAVING A CONTACT ARM CONNECTED TO THE HOUSING COVER AND G. SAID THIRD SWITCH BEING ELECTRICALLY CONNECTED WITH THE FIRST INDICATOR WHEREBY BOTH INDICATORS ARE SIMULTANEOUSLY ENERGIZED BY MOVEMENT OF THE HOUSING COVER.

Description

United States Patent [191 Nelson 51 Sept. 10, 1974 TAMPERPROOF ALARM SWITCH [76] Inventor: James E. Nelson, 304 Harvard Ave.,

Wenonah, NJ. 80090 [22] Filed: June 18, 1963 [21] Appl. No.: 289,783

[52] US. Cl 340/274, 340/29, 340/276 [51] Int. Cl. G08b 13/08 [58] Field of Search 340/213 A, 215, 216, 274,

[56] References Cited UNITED STATES PATENTS 3,045,226 7/1962 Trayner 340/276 3,087,145 4/1963 Fruh 340/274 Primary Examiner--Maynard R. Wilbur Assistant Examiner-H. A. Birmiel Attorney, Agent, or Firm-R. S. Sciascia; J. F. Skehan EXEMPLARY CLAIM 1. An alarm system for a normally closed security room having a movable room closure providing access thereto, which comprises,

a. a normally closed housing within the security room having a movable housing cover providing access thereto,

b. a first switch in the housing, a first remote indicator and electrical connections therebetween,

c. a second switch in the housing, a second remote indicator and electrical connections therebetween,

d. said first switch having a contact arm which is operable by movement of the room closure to independently energize the first indicator,

e. said second switch having a contact arm connected tothe housing cover and operable by movement of the housing cover to energize the second indicator,

f. a third switch in the housing having a contact arm connected to the housing cover and g. said third switch being electrically connected with the first indicator whereby both indicators are simultaneously energized by movement of the housing cover.

1 Claim, 1 Drawing Figure YINVENTOR.

Y JAMES E. NELSON ATTO RNEY TAMPERPROOF ALARM SWITCH The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to improvements in electrical signal systems and it relates particularly to such systems which are adapted for use in maintaining security in a number of areas such as security areas on shipboard.

The principal object of the present invention is to provide a tamperproof electrical signal system for a plurality of security areas which is arranged to indicate accurately the area involved.

Another object of the present invention is to provide an electrical signal system for a plurality of security areas whereby a signal panel may be observed to determine accurately and readily the particular area involved.

A further object of the invention is to provide an electrical signal system for a plurality of security areas which indicates the particular security area which is being entered without authorization.

A further object of the invention is to provide an electrical signal system for a plurality of security areas which indicates when components of the system located in a particular area are being tampered with.

The invention involves the use of a plurality of switch devices which are arranged to locate one in each of the security areas and each device is in the form of a housing enclosing switch structure and operating equipment therefor. The switch structure comprises a first switch which is arranged to be operative by the movement of a closure for an access opening, such as the door of a security area, and a second switch which is operative by movement'of a closure such as the cover of the switch housing. The first switch functions to provide a signal to show that a security area is entered by an unauthorized person and the second switch functions to provide a signal to show that a person, who may be properly within the security area, is tampering with the interior of the switch device. The system for the signals is in the form of an independent indicator for each of the first switches and a single indicator for all of the second switches. The switch mechanism of the second switch of each device is such that it is tied into the indicator of the first switch in order that operation of the second switch will indicate to an operator, by the simultaneous indication on one of the first switch indicators, the location of the particular device or security area which is involved.

For a better understanding of the invention, reference may be had to the accompanying drawing which is generally a diagrammatic view of the signal system with one switch device sectioned to show details.

In the upper portion of the FIGURE, three switch device housings are shown and identified by the numeral to be representative of a plurality of such devices, one of which will be located in each security area. In the lower portion of the FIGURE the independent signal equipment for the first switches is indicated at 10 while the single signal equipment for all of the second switches is indicated at 11.

The housing 10 at the left of the F IGURE is sectioned to show details and is formed of side walls 12-12, bottom wall 13, rear wall 14 which along with a front wall (not shown) are formed into a closed unit which is provided with a removable cover C which forms access means for the housing. A roller B is provided for actuating the first switch and has a pin 15 extending therefrom which is mounted for movement in a slotted lug 16 extending from the inner face of the wall 12'. A por- 5 tion of the roller extends through an opening, not shown, in the side wall 12' and is positioned to be moved by the opening or closing movement of a door of the security area in which the housing is located. The pin is shown as disposed midway of the lug 16 and indicates the closed position of a door. Spring means may be provided to permit the roller B to return to the shown position after it has moved in either direction by the door movement.

An actuating arm 17 has its lower end pivoted at 18 and its upper end provided with a follower 19 which reposes in contact with the peripheral surface of roller B within the housing, as shown. A switch arm 20 has its upper end pivotally mounted at 21 and its lower end in inoperative position between a pair of contacts indicated at 2222. A connector 23 is fixedly mounted to both the actuating arm 17 and the switch arm 20 and positions the switch arm, in accordance with movement of roller B, in contact with one or the other of contacts 2222. Connections 24 and 24' are provided between both of the contacts 2222 and one side 25 of the circuitry for the signal equipment 10'. The switch arm 20 is connected with the other side 26 of this circuitry by line 27. The switch arms 20 in each of the housings 10 are thus connected with the signal equipment 10 by parallel circuits.

The cover C is provided with an actuating arm 30 which is connected to an upper switch arm 31 and also to a lower switch arm 32. The upper switch arm is pivoted at 33 while the lower switch arm is pivoted at 34 and both are inoperative in their positions shown in the FIGURE while upper and

lower contacts

35 and 36 are respectively positioned for coaction with the

switch arms

31 and 32 when the cover is raised. The upper switch arm 31 is connected to one side 37 of the circuitry of signal 11 while the upper contact 35 is connected to the other side 38 of this circuitry. Thus, as will be seen from the drawing, switches 31 of the housings 10 are connected in series parallel with the single indicator 11. The lower switch arm 32 is connected to the one side 26 of the circuitry of signal 10' while the lower contact 36 is connected to the other side 25 of the circuitry of signal 10'. Thus the. lower switches 32 in the housings 10 are also connected in parallel circuits with the indicators 10'.

The structures of the signals of 10' and 11 are identical and the elements of 10' and 11 will be identified in a manner to correspond. Referring to the signal 10 located below the sectioned housing 10, the numeral 40 indicates a switch arm which has its lower end pivoted at 41 and a connection 42 is provided with the X side of the power supply as shown. An indicator, such as a light 43, is connected to the Y side of the power supply by line 44 and a contact 45 is connected to indicator 43 and located in cooperating relation with switch arm 40 and is normally out of contact with the switch arm 40 in the position as shown in the FIGURE.

At R is indicated a relay which is operative, when the circuit through one or the other of contacts 2222 is energized, to make contact between the signal switch arm and contact 45 for operating the light 43. A holding resistor is located between

sides

25 and 26 of the circuitry for signal equipment 10' for maintaining the arm 40 out of contact with contact 45 and also a holding resistor 50' is located between

sides

37 and 38 of the circuitry for signal equipment 11 for maintaining switch arm 40' normally out of contact with contact 45'.

it will be understood from the above description that movement of the actuating arm 17 by roller B will energize the light signal 43 and the operator will know which security area is involved since each security area has a separate light signal in equipment which is operative by roller B. When, however, the cover C is tampered with, without operation of a signal of equipment 10, the lower switch arm 32 will operate a signal of this equipment and simultaneously therewith the upper switch arm 31 will operate the signal 43 of signal equipment 11' and the operator will know the location of the security area wherein the switch housing is being tampered with.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. An alarm system for a normally closed security room having a movable room closure providing access thereto, which comprises,

(1. said first switch having a contact arm which is operable by movement of the room closure to independently energize the first indicator,

e. said second switch having a contact arm connected to the housing cover and operable by movement of the housing cover to energize the second indicator,