US3887910A

US3887910A - Burglar alarm

Info

Publication number: US3887910A
Application number: US325741A
Authority: US
Inventors: Vernon H Jones
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-11-15
Filing date: 1973-01-22
Publication date: 1975-06-03
Anticipated expiration: 1992-06-03

Abstract

An electrically powered burglar alarm which is turned on by a switch operated by an easily released trigger mechanism which holds the switch in the off position as long as a retaining member is in position on the trigger mechanism. The switch and trigger mechanism are attached to a housing in a fixed location and the switch is connected to a power source. The retaining member which is a clip or ring is attached to one end of a thin trap line and the other end of the line is anchored at a remote point from the housing so that any slight contact with the line will pull off the retaining member and thereby release the trigger mechanism to close the switch. Closing of the switch completes the circuit to a siren, bell, or other warning device. The alarm may also include a manually operated panic switch and other components such as timers, relay switches, intermittent signal components and other such accessories.

Description

June 3, 1975 United States Patent 1 1 Jones 3,641,571 2/1972 Kitman 340/274 X 1 1 BURGLAR ALARM Primary Examiner-John W. Caldwell Assistant ExaminerWilliam M. Wannisky [22] Filed:

, Agent, or Firm-Paul E. Milliken Attorney [21] Appl. No.: 325,741

[57] ABSTRACT An electrically powered burglar alarm which is turned Related U.S. Application Data Continuation-impart of Scr. No. 306,709, Nov. 1972, abandoned.

on by a switch operated by an easily released trigger mechanism which holds the switch in the off position [52] 340/276; 2O0/6Ll9; 200/153 F; as long as a retaining member is in position on the 200/331 trigger mechanism. The switch and trigger mechanism [51] Int. Cl.

are attached to a housing in a fixed location and the {58] Field of Search switch is connected to a power source. The retaining member which is a clip or ring is attached to one end of a thin trap line and the other end of the line is anchored at a remote point from the housing so that any [561 References C'ted slight contact with the line will pull off the retaining UNITED STATES PATENTS member and thereby release the trigger mechanism to or other warning device. The also include a manually operated panic switch and other components such as timers, relay bell switches, intermittent signal components and other 14 Claims, 18 Drawing Figures S m .w r. M w y S a E O C m m .1 mm h km W C3 S 4 944 4 7 1 7 3- 24 229 2 '1 //19/ 0 600 .40 4 Iw44 .4 30 336 11 M H "O u 0 H, 2 644700572 797003003 30257069 94072459 1 1 .4 22233333 SHEET FIG.

FIG. 4

SHEET 620 FIG. I?

lld

PATENTEDJUHB m SHEET FIG. l8

BURGLAR ALARM This is a continuation-in-part of application Ser. No. 306,709 filed Nov. 15, 1972 now abandoned.

PRIOR ART The closest prior art known to applicant are US. Pat. Nos. 2,640,894; 3,175,207; 3,427,608 and 3,465,325.

OBJECTS OF THE INVENTION A primary object of the invention is to provide a burglar alarm which is actuated by the slightest contact by an intruder with a trap line.

Another object of the invention is to provide a burglar alarm in which the trigger mechanism may be op erated by any one of a number of trap lines, extending in various directions from the trigger mechanism and does not require that the trap line extend in any one particular direction.

Still another object of the invention is to provide a burglar alarm which is simple but versatile and which permits various components to be plugged into the basic control assembly unit.

These and other objects of the invention will become more fully apparent as the description proceeds in the following specification and the attached drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is perspective view of one embodiment of the invention with portions broken away to show the interior parts;

FIG. 2 is a fragmentary side view showing a modification of the trigger mechanism;

FIG. 3 is a fragmentary side view showing the same trigger mechanism as that shown in FIG. 1;

FIG. 4 is a plan view showing a spring clip retainer for holding the trigger with the switch in the off position;

FIG. 5 is a plan view of a rubber ring retainer which may be used in lieu of the spring clip of FIG. 5;

FIG. 6 is a side elevational view showing another embodiment of the invention in which the housing is made of molded plastic and a series of plug in components are plugged into the basic control unit;

FIG. 7 is a simplified diagrammatic view showing the circuit of the embodiment shown in FIG. 6;

FIG. 8 is a perspective view of another embodiment of the invention in which the control assembly is mounted onto a cover plate which fits onto a conventional wall rough outlet box;

FIG. 9 is a simplified view showing a multiple trap line arrangement connected to the same single trigger mechanism;

FIG. 10 is a perspective view of another embodiment of the invention including a shut-off timer;

FIG. 11 is a circuit diagram of the embodiment shown in FIG. 10 connected to a siren;

FIG. 12 is a simplified diagrammatic view showing another modification a timer and shut-off switch;

FIG. 13 is a perspective view of a siren with an intermittent signal component therein;

FIG. 14 is fragmentary front elevational view showing another embodiment of the invention showing a spring loaded take up reel for the trap line;

FIG. 15 is a fragmentary cross sectional view taken on line I5I5 of FIG. 14;

FIG. 16 is a fragmentary front elevational view showing another embodiment of the invention in which a weight holds the trigger arm in the down position until it is knocked off by the door being opened;

FIG. 17 is a side elevational view of the central control unit with the trigger arm being held in the down position by a weight placed thereon which is pulled off when the trap line is contacted; and

FIG. 18 is a diagrammatic view of another embodiment of the invention showing a plug-in high frequency control unit which which permits the system to use existing home wiring without additional wires.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows one embodiment of the invention in which the entire alarm control assembly is indicated by the numeral 1. The control assembly 1 has a housing 2 made of sheet metal or other suitable material. The housing 2 is made of two mating parts which fit together to form a hollow rectangular box. The parts may be fastened together by rivets, snaps, screws or any suitable means. The housing can be constructed in any number of ways well known in the art. The invention does not reside in the housing but in the assembly of various working parts and in particular the trigger mechanism and in the manner the trap line is connected to the trigger mechanism. An electrical power input 3 which plugs into a conventional electrical outlet receptical (not shown) is mounted in the back wall of the housing 2. The input 3 has

terminals

4 and 5. Terminal 4 is connected by line 6 to a terminal 7 of a power output plug 8 which is mounted in a side wall of the housing 2 to provide power to a plug-in warning siren or other such device (not shown). A normally closed trigger switch 9 is attached to the back wall of the housing 2 by a bracket 10. The switch 9 has a trigger arm 11 hinged to a pivot yoke 12 in such manner that it protrudes through an opening 13 in the front wall of the housing 2 and extends adjacent to a tapered flange 14 of a seat member 15. The relative position of the trigger arm 11 is such that when it is held against the flange 14 by a spring clip retainer 16, the arm 11 depresses a button 17 which opens the normally closed switch 9. The seat member 15 is attached to the housing 2 by a screw 18 or other suitable means.

The terminal 5 of the input 3 is connected by a line 19 to an input terminal 20 of the switch 9. An output terminal 21 of switch 9 connects through a panic switch 22 to a terminal 23 of the output plug 8. The panic switch 22 may be any conventional manually operated on/off type of switch. The panic switch 22 is preferably provided with a long extension cord 24 so that it may be operated at a location remote from the from the control assembly 1.

A thin trap line or release line 25 has one end connected to the retainer clip 16 and the other end anchored at a remote location from the housing 2. The trap line 25 is normally positioned across a path of normal traffic flow in the house such as across a doorway, a hallway, a stairway or any other location where an intruder is likely to come in contact with it and turn on the alarm.

FIGS. 2 and 3 show two alternative trigger mechanisms. In FIG. 3 the retainer 16 is clipped over the out side of both the trigger arm 11 and the flange 14 to hold the button 17 on the switch 9 depressed, thereby holding the switch 9 open until the line 25 pulls off the retainer I6 and releases the trigger arm 11 thereby permitting the switch to assume its normally closed positron.

The mechanism in FIG. 2 operates just the opposite to that of FIG. 3. In FIG. 2, the retainer 16 is wedged between the arm 11 and the flange 14 to hold them apart so that the arm 11 depresses the button 17 on the switch 9 which is positioned above the arm 11 instead of below it as in FIG. 3.

A particular feature of the invention is that due to the manner in which the flange 14 is tapered on at least one side as shown in FIGS. 2 and 3, the retainer 16 is very easily pulled loose from the trigger arm 11 and flange 14 by a slight pull on the line 25 regardless of which direction the line 25 extends from the assembly 1.

Another alternative feature is shown in FIG. 9 which shows a group of lines 25 extending in various directions from the trigger arm 11 to form a web-like configuration to cover a larger area than that covered by a single line. By using multiple trap lines attached to the same retainer and extending out in a radial direction, therefrom, one can protect more than one door and/or window with one control assembly or a single trap line can be set at any angle within 90 from the straight for ward position as shown in FIG. 9.

FIG. 4 shows in greater detail the spring clip retainer 16 used in FIGS. 1 through 3. FIG. shows another alternative retainer 16a which is preferably a rubber ring shown being used in the embodiment in FIG. 6.

It should be understood that FIG. 6 has been simplifled to illustrate the manner in which the housing 2a can be made of solid molded plastic with all circuit components and connection lines being cast or potted" in position within the housing. A clearance cavity 26 is provided within the housing to permit movement of the arm 11a to operate switch 90 in the same manner as described in FIG. 2, however it can also be reversed to operate the same as shown in FIG. 3.

The circuitry of FIG. 6 as illustrated in FIG. 7, is the same as that of FIG. 1 except the panic switch 22a is a plug-in unit connected through a plug 27 instead of being permanently wired into the circuit as shown in FIG. 1. The panic switch 22a could of course, be wired directly into the circuit in the molded housing 2a if desired similar to the manner switch 22 is wired into the circuit in FIG. 1. The device in FIG. 2 has

prongs

28 and 28a which plug into a power source just like the device in FIG. 1. The plug 27 in turn plugs into the output of the control assembly 10. An intermittent signal plug 29 is plugged into the output of the panic switch plug 27. A plug 30 of a warning siren 31 is plugged into the output of the intermittent signal plug 29.

A bracket 32 for mounting the housing 2a in a fixed location is attached to the housing by a screw 33. The bracket 32 may not be needed if the assembly is plugged into a conventional base plug but may be needed if the assembly is plugged into an extension cord and mounted on a wall or other fixed surface. A bracket similar to 32 may also be provided on the housing 2 in FIG. 1.

Other plug-in components such as a timer, a relay switch and other signal control devices may be plugged in between the output of the assembly la and the warning siren 31 or may be plugged into the circuit in lieu of or in addition to the intermittent signal plug 29 depending upon what control functions are desired. It is obvious that other warning signal devices such as bells, buzzers. lights or recording devices can be used in lieu of or in addition to the siren 31. The device can also be used to activate telephone dialing equipment or turn on flood lights.

As shown in FIG. 7, the prong 28 is connected directly through a series of plug-in prongs in

plugs

27, 29 and 30 to one of the input lines to the siren 31. The prong 28a connects through the switch 90, the panic switch 22a aand a contact arm 32 of the intermittent plug 29 and then through the plug 30 to an input of the siren 31.

FIG. 8 shows a control assembly 1b mounted on a switch plate 2b which fastens to a rough service box 33 as an alternative to the plug-in assembly 1 in FIG. I. The box 33 has a conduit 34 carrying positive line 35 from a power source 36 and a line 37 connected through a relay switch 38, a timer 38a and an intermittent signal device 38b to a siren 31a. The plate 2b is fastened to the box 33 by screws 39 passing through holes 40 and engaging threaded holes 41 in the box 33.

A switch 9b similar to the switch 9 is mounted by a bracket 10b on the plate 212 and operates in the same manner as the switch 9 when the retainer 16b is pulled off the trigger arm 11b by the line 25b. Line 35 connects to terminal 20b. Terminal 21b is connected through panic switch 22b to line 37, which is connected through the device 38 to one terminal of siren 310. Line 42 connects the other terminal of siren 310 through the

devices

38, 38a and 38b to ground at the power source.

OPERATION Since all three embodiments shown in FIGS. 1, 6 and 8 operate in the same manner, only the device in FIG. 1 will be explained in the interest of brevity. The prongs of the input 3 are plugged into a conventional wall out let (not shown). A warning signal device such as the siren 31 in FIG. 2 is plugged into the output receptacle 8. The retainer clip 16 is placed over the trigger arm 11 and flange 14 of the seat member 15 in such manner that the arm 11 is held against the flange 14 as shown in FIG. 1. This holds the switch 9 in the open position by depressing the button 17. The panic switch 22 is set in the closed position. The line 25 has one end connected to the retainer 16 and the opposite end anchored at a remote location from the assembly 1.

If an intruder even lightly touches the line 25 the retainer 16 immediately pulls off the trigger arm 11 and flange l4 and releases the trigger arm 11 which moves up and permits the switch 9 to close thereby completing the circuit and turning on the siren 31. If an intermittent signal plug such as 29 in FIG. 2 is used, then the siren will operate intermittently. Otherwise it will operate continuously until either the switch 9 is opened again or the panic switch 22 is turned off or until the system is shut off by a timer.

If it is desired to use only the panic switch 22 and not the switch 9, this can be done by leaving the retainer 16 off so that the switch 9 remains closed. Then one can operate the siren 31 merely by turning on the panic switch 22 to scare away an intruder if one is discovered. The control button for the panic switch 22 would normally be placed at some convenient location such as near ones bed.

The device shown in FIG. 2 can be operated without the panic switch or other components simply by plugging the plug 30 of siren 31 directly into the output of assembly la.

The embodiment shown in FIG. is quite similar to the one in FIG. 1 except that it contains a built in timer switch. The control assembly 1c in FIG. 10 has a housing 2c which contains a trigger operated switch 90 (see FIG. 11) similar to the switch 9 in FIG. I. The switch 96 has a trigger arm 11c protruding through an opening BC in the housing 2c and lying adacent outwardly extending flange 14c and held against flange 14c when the retainer clip 16c is placed in position with trap line 25c attached thereto. The assembly 10 has input power prongs 43 and 44 extending from the housing to plug into a conventional wall outlet (not shown). The housing has an output power plug 8c into which a siren such as 31c or 31d in FIGS. II and 13 respectively can be plugged. Other components such as panic switches and the like can be plugged in between the plug 86 and the siren as previously described in the previous embodiments. A timer 45 driven by a motor 46 (FIG. 11) is mounted in the housing 2c indicated by the dotted line in FIG. 11. The prong 44 is connected by line 47 through switch 9c to terminal 48 of motor 46 and ter minal 49 of the siren 31c. Prong 43 connects through line 50 manual switch 51, timer switch 52 to terminal 53 of motor 46 and terminal 54 of the siren 31c. An adjustable off lever 55 is rotated by the timer motor 46 until it touches the trigger arm 56 of the switch 52 and turns off the switch 52, the siren 31c and the motor 46. While the siren is shown in FIG. 11 for simplicity as being wired directly to the circuit of control assembly lc, it could also be plugged in to an output plug such as the plug 80 in FIG. 10.

OPERATION OF TIMER CONTROL ASSEMBLY In operation, the control assembly 1c of FIGS. 10 and I1 is plugged into a wall outlet and manual switch 51 is closed. The timer is set in such a position that the switch 52 is closed and the shut-off lever 55 is set at a position which will permit the timer to operated for the desired amount of time before the lever 55 contacts switch trigger arm 56 and turns off switch 52, thereby shutting off both the siren 31c and the motor 46. The trigger arm 11c is clipped down to the flange 14c, thereby opening the switch 90. The trap line c is connected to clip 15c at one end and the other end is anchored at a remote point as previously described in the other embodiments. When an intruder touches trap line 250 and pulls the clip 160 off the trigger arm 11c and flange 14c, switch 9c closes and completes the circuit through the motor 46 and siren 31c. The timer starts to run for the preset number of minutes until the arm 55 touches trigger arm 56 and opens switch 52, thereby shutting off both the motor 46 and the siren 310. This means that the siren 316 will not continue to run until manually turned off but will shut off automatically and thereby avoid disturbing the neighbors any longer than necessary to frighten off the intruder or provide a warning of his presence.

Another variation of timer is shown in FIG. 12 in which a motor driven cam 57 makes one complete revolution in the time that the siren is to remain on. The cam 57 rotates until the depressed spot 58 is aligned with trigger arm 11d, then the trigger arm 11d is released and permits the switch 9c to open and shut off the siren and timer motor. The cam and switch could also be made to work in the opposite manner in which the cam gradually opens the switch when the trigger arm rides up onto a high spot on the cam.

FIG. 13 illustrates an intermittent signal generating component 59 is connected directly into the input lead wires going into the siren 31d. This will cause the siren to operate intermittently rather than continuously and may attract more attention than a continuous siren. It will of course be realized that a plug-in panic switch such as 22a in FIG. 6 can also be used with the embodiments shown in FIGS. 10 and 11 as well as any other desired plug-in components which may be plugged in between the output 8c and the siren 310.

While in FIGS. 4 and 5 a retainer clip 16 and a retainer ring 16a has been illustrated it should also be mentioned that a conventional paper clip can also be used in lieu of the retainer devices previously shown. It should also be mentioned that in lieu of the retainer clip 16, a weight may be placed on top of the trigger as shown in FIGS. 16 and 17 and later described herein to hold the trigger arm in the down position which the switch open until the weight is knocked off or pulled off by a trap line.

In FIG. 16 a central control unit 60 is plugged into a wall outlet near a door 61. The control unit 60 has an outwardly extending seating flange 62 and an outwardly extending trigger arm 63 and which is placed a weight 64 which holds the trigger arm 63 down against the flange 62. An arm 65 extends from the weight 64 a sufficient distance toward the door 61, that when the door is opened it contacts the end of the arm 65 and knocks the weight 64 off the trigger arm 63 thereby causing the trigger arm 63 to raise and close the switch inside the control unit 60 and turn on the alarm as previously described regarding the other embodiments. In other words the weight 64 is merely a substitute retaining means for the clips previously described.

In FIG. 17 a central control unit 60a has a seating flange 62a and a trigger arm 63a held down by a weight 64a similar to the weight 64 in FIG. 16 except that instead of the weight being pushed off by a door touch and arm attached to the weight, the weight 640 is pulled off by a trap line 66 when the trap line is contacted by an intruder.

FIGS. 14 and 15 show another modification of the invention in which a central control unit 67 is plugged into a wall outlet near a door 68. A retaining clip 69 is placed over an outwardly extending flange 70 and a trigger arm 71 to hold the switch in the control unit 67 open as described in previous embodiments. A trap line 72 extends from the clip 69 to a spring loaded take up reel 73 mounted on the door 68. The take up reel 73 works on the same principle as a reel type tape measure. The reel 73 has a release button 74 which is contacted by a resilient spring like arm 75 attached to the door frame 76. As soon as the door 68 is opened the arm 75 touches the release button 74 and causes the reel to wind up the trap line 72 and thereby pull the clip 69 off the trigger arm 71 and flange 70 thereby cause the switch in the control unit 67 to close and turn on the alarm as described in previous embodiments.

Various other modifications can be made in the embodiments shown herein and the various embodiments can be combined with each other in various ways without departing from the scope of the invention.

FIG. 18 shows another embodiment of the invention in which the alarm system can be plugged into a conventional I I0 volt AC. power line in a home or business place without any special wiring being installed to carry the signals to turn on the alarm. In FIG. 18 a conventional master control box or power source 77 has a conventional A.C. circuit having a power line 78 and a ground line 79 connected thereto. The

lines

78 and 79 connect to conventional outlet receptacles 80a through 801.

A central control unit 81a similar to the unit 1c in FIGS. and 11 is plugged into outlet 80c with a plug 82 having input prongs 83 and output slots 84. The plug 82 is connected by a cord 85 to the circuit of the control unit 810 having a timer switch 86 and a trigger switch 87 mounted in the housing 88 and wired in a manner similar to the control unit 10 previously described. A trigger arm retainer 89 is clipped on the trigger switch 87 in the same manner previously described in the other embodiments and a trap line 90 has one end attached to the retainer 89 and the opposite end anchored at a remote location. A high frequency signal transmitter 91 of a type commercially available is plugged into the output slots 84 in plug 82. The transmitter 91 is turned on. A siren 92 is connected through a high frequency receiver switch 93 to outlet 80a. If the trap line is disturbed the trigger switch 87 closes and powers the transmitter 91 which in turn sends a high frequency signal back through the switch 87 and through the entire circuit to all the outlets 800 through 80c. The high frequency signal passes from outlet 80a through cord 94 to high frequency receiver switch 93 which turns on and causes power to flow to the siren 92 causing it to operate. The timer switch 86 in the control unit 81a provides a short delay in the actuation of the siren 92 and then turns off the siren 92 after a certain length of time.

The siren 92 can also be actuated by the high frequency transmitter switch 91a plugged into outlet 80d. The switch is a manually operated panic switch which can be turned on if a prowler is detected to operate the siren. The switch 91a performs the same function as the switch 91 except that it is operated manually while the switch 91 is left on and powered through the trigger switch 87.

A photoelectric eye system can also be used in combination with a high frequency transmitter to turn on the siren 92 when a light beam is interrupted. A photoelectric exciter lamp unit 94 is plugged into outlet 80b and transmits a light beam 95 to a receiver unit 96 plugged into outlet 80. Interruption of the beam 95 causes a relay switch in the unit 96 to close and cause power to flow through

plugs

97 and 98 into the high frequency transmitter 91b which in turn sends a high frequency signal back through

plugs

97 and 98 and into the power circuit to the receiver 93 thereby turning on power to operate the siren 92. The control unit 81b is used only as a timer switch in combination with the photoelectric units and hence the retainer and trap line are not positioned on the trigger switch 87a so that it remains closed. In this combination the photoelectric units and not the trigger switch 87a causes the alarm to operate by sensing an intruder. It should also be recognized that other switch means can be used in place of the trigger switch or the photoelectric eye units. For example floor mat contact switches and various other types of sensing devices can be used to trigger the alarm in response to the presence of an intruder.

In setting an up a complete alarm system in a home one would use one or more siren or warning device such as the siren 92 with each warning device having a high frequency receiver switch 93 either built into the device as an integral part thereof or at least connected into the circuit to control the power to the warning device. One can then connect into the power circuit any number of switching or sensing devices such as those illustrated in FIG. 18 used in combination with a high frequency transmitter such as 91, 91a or 91b. If any one of the high frequency transmitters is connected into the power line by any means then it will transmit a signal to the receiver switch 93 which will turn on the siren 92 or other device. Thus one can place multiple traps or detection devices at various locations throughout the house and any one of these devices can turn on the alarm. The use of the high frequency transmitter and receiver switch eliminates the need for extra wiring for the alarm systems but permits the use of the existing house wiring both for power supply and for sending the signals to turn on the alarm.

The various units of equipment shown herein can be combined in a multitude of ways and combinations without departing from the scope of the invention.

1 claim:

1. A burglar alarm for use with an existing power circuit having a plurality of power outlet receptacles at various remote locations from each other the alarm comprising:

a. a trigger operated switch assembly connected between a power input and power output for turning off or on power from the input to the output, the power input of the switch assembly being plugged into one of the power outlet receptacles in an existing power circuit, said trigger operated switch assembly having a trigger operated switch and a trigger mechanism comprising:

1. a fixed trigger arm positioning member attached to the housing and extending outwardly therefrom,

2. a trigger arm operatively associated with the trigger operated switch and extending through an opening in the housing to a position adjacent the positioning member, an outwardly extending flange which is tapered from a larger thickness at the inner end to a smaller thickness at the outer end to provide greater ease of removal of the retaining member, said trigger arm movable to and from the positioning member,

3. a spring clip retaining means simultaneously engaging the positioning member and the trigger arm to resiliently position the trigger arm with respect to the positioning member, thereby causing the switch to be in an open position, and

4. a release line having one end attached to the retaining member and the opposite end anchored at a remote location from the trigger mechanism,

5. whereby any tension exerted on the line will pull the retaining member out of engagement with the positioning member and the trigger arm and release the trigger arm thereby permitting the switch to close, and

a. a high frequency signal transmitter connected to the power output of the trigger operated switch assembly to send a high frequency signal through the power circuit when the trigger operated switch is closed;

b. a high frequency signal receiver connected to a predetermined location on the power circuit said receiver being responsive to signals transmitted by the signal transmitter over the power circuit to close a switch connected between an input and and output of the receiver; and

c. an electrically operated warning signal device connected to the output of the receiver to produce a warning signal when the trigger operated switch is closed and a high frequency signal from the transmitter causes the switch in the receiver to close thereby causing electrical current to flow to the warning signal device.

2. A burglar alarm as claimed in claim 1 wherein the warning signal device is a siren and the high frequency receiver is an integral part of the siren.

3. A burglar alarm as claimed in claim 1 wherein a separate high frequency transmitter having an on-off switch is connected into the power circuit independently of the trigger operated switch to serve as a manually operated switch to turn on the warning signal device.

4. A burglar alarm comprising:

a. a housing adapted to be mounted in a fixed location;

b. electrical power input means attached to the housing for connection to an electrical power source;

c. electrical power output means attached to the housing;

d. a trigger operated switch within the housing connected between the power input and power output means for turning off or on power from the input to the output means;

e. a trigger mechanism comprising;

f. an electrically operated warning signal device connected to the power output means to produce a warning signal when the trigger operated switch is closed.

5. A burglar alarm as claimed in claim 4 wherein a plurality of release lines extend radially outwardly from the retaining member when it is mounted on the trigger arm and flange thereby forming a web-like configuration.

6. A burglar alarm as claimed in claim 4 wherein a manual switch is connected into the circuit of the alarm in such manner that both the trigger operated switch and the manual switch must be in the closed position before the warning signal device will operate.

7. A burglar alarm as claimed in claim 4 wherein the manual switch is plugged into the circuit between the output means on the housing and the warning signal device.

8. A burglar alarm as claimed in claim 4 including an intermittent signal generating component connected into the circuit of the device to provide intermittent operation of the warning signal device.

9. A burglar alarm as claimed in claim 4 wherein the warning signal device is a siren.

10. A burglar alarm as claimed in claim 4 wherein the housing is made from molded plastic with the circuit components molded in place within the housing.

11. A burglar alarm as claimed in claim 4 wherein a high frequency signal transmitter is connected through the trigger operated switch to the power source and a high frequency receiver switch mechanism responsive to a signal from the high frequency transmitter is con nected between the warning signal device and the power output means.

12. A burglar alarm as claimed in claim 4 wherein the retaining member is a spring clip which fits over both the trigger arm and the flange to hold the trigger arm against the flange and thereby hold the switch in the open position.

13. A burglar alarm as claimed in claim 4 including:

a. an electric motor driven timer mounted in the housing said timer being inoperative while the trigger operated switch is open but becoming operative when the trigger operated switch is closed;

b. a timer switch operated by the timer connected between the power input and power output for turning off power from the input to the output means and to the timer at a predetermined period of time after the trigger operated switch has been closed; and

c. an electrically operated warning signal device con' nected to the power output means to produce a warning signal when the trigger operated switch and the timer switch are both closed.

14. A burglar alarm as claimed in claim l3 wherein the warning signal device is a siren having an intermittent signal component therein.

Claims

1. A burglar alarm for use with an existing power circuit having a plurality of power outlet receptacles at various remote locations from each other the alarm comprising: a. a trigger operated switch assembly connected between a power input and power output for turning off or on power from the input to the output, the power input of the switch assembly being plugged into one of the power outlet receptacles in an existing power circuit, said trigger operated switch assembly having a trigger operated switch and a trigger mechanism comprising: 1. a fixed trigger arm positioning member attached to the housing and extending outwardly therefrom, 2. a trigger arm operatively associated with the trigger operated switch and extending thRough an opening in the housing to a position adjacent the positioning member, an outwardly extending flange which is tapered from a larger thickness at the inner end to a smaller thickness at the outer end to provide greater ease of removal of the retaining member, said trigger arm movable to and from the positioning member, 3. a spring clip retaining means simultaneously engaging the positioning member and the trigger arm to resiliently position the trigger arm with respect to the positioning member, thereby causing the switch to be in an open position, and 4. a release line having one end attached to the retaining member and the opposite end anchored at a remote location from the trigger mechanism, 5. whereby any tension exerted on the line will pull the retaining member out of engagement with the positioning member and the trigger arm and release the trigger arm thereby permitting the switch to close, and a. a high frequency signal transmitter connected to the power output of the trigger operated switch assembly to send a high frequency signal through the power circuit when the trigger operated switch is closed; b. a high frequency signal receiver connected to a predetermined location on the power circuit said receiver being responsive to signals transmitted by the signal transmitter over the power circuit to close a switch connected between an input and and output of the receiver; and c. an electrically operated warning signal device connected to the output of the receiver to produce a warning signal when the trigger operated switch is closed and a high frequency signal from the transmitter causes the switch in the receiver to close thereby causing electrical current to flow to the warning signal device.

1. A burglar alarm for use with an existing power circuit having a plurality of power outlet receptacles at various remote locations from each other the alarm comprising: a. a trigger operated switch assembly connected between a power input and power output for turning off or on power from the input to the output, the power input of the switch assembly being plugged into one of the power outlet receptacles in an existing power circuit, said trigger operated switch assembly having a trigger operated switch and a trigger mechanism comprising:

4. A burglar alarm comprising: a. a housing adapted to be mounted in a fixed location; b. electrical power input means attached to the housing for connection to an electrical power source; c. electrical power output means attached to the housing; d. a trigger operated switch within the housing connected between the power input and power output means for turning off or on power from the input to the output means; e. a trigger mechanism comprising;

5. whereby any tension exerted on the line will pull the retaining member out of engagement with the positioning member and the trigger arm and release the trigger arm thereby permitting the switch to close, and f. an electrically operated warning signal device connected to the power output means to produce a warning signal when the trigger operated switch is closed.

5. whereby any tension exerted on the line will pull the retaining member out of engagement with the positioning member and the trigger arm and release the trigger arm thereby permitting the switch to close, and a. a high frequency signal transmitter connected to the power output of the trigger operated switch assembly to send a high frequency signal through the power circuit when the trigger operated switch is closed; b. a high frequency signal receiver connected to a predetermined location on the power circuit said receiver being responsive to signals transmitted by the signal transmitter over the power circuit to close a switch connected between an input and and output of the receiver; and c. an electrically operated warning signal device connected to the output of the receiver to produce a warning signal when the trigger operated switch is closed and a high frequency signal from the transmitter causes the switch in the receiver to close thereby causing electrical current to flow to the warning signal device.

11. A burglar alarm as claimed in claim 4 wherein a high frequency signal transmitter is connected through the trigger operated switch to the power source and a high frequency receiver switch mechanism responsive to a signal from the high frequency transmitter is connected between the warning signal device and the power output means.

13. A burglar alarm as claimed in claim 4 including: a. an electric motor driven timer mounted in the housing said timer being inoperative while the trigger operated switch is open but becoming operative when the trigger operated switch is closed; b. a timer switch operated by the timer connected between the power input and power output for turning off power from the input to the output means and to the timer at a predetermined period of time after the trigger operated switch has been closed; and c. an electrically operated warning signal device connected to the power output means to produce a warning signal when the trigger operated switch and the timer switch are both closed.