US3900841A - Intrusion alarm control system - Google Patents

Abstract

Sensors detect a disturbance and initiate a timing mechanism, the timing mechanism controlling the actuation, in a logically timed sequential manner, of a plurality of warning, alarm and/or monitoring functions in a degree reflecting the severity of the intrusion and then resetting the system to its pre-intrusion condition. Utilization of the timing mechanism greatly diminishes the possibility of false alarms, reduces harassment alarms associated with overzealous, authorized usage of the property, and provides a deterrence capability, this being made possible by the mechanism''s ability to discriminate between relative levels of abuse. The system can be employed to perform a deterrence and warning function in conjunction with any property desired to be protected but is particularly useful in association with unattended property which must be capable of withstanding a limited degree of abuse or disturbance from over-zealous but legitimate users of the property.

Description

United States Patent [191 Buckles [111 3,900,841 [4 1 Aug. 19, 1975 1 INTRUSION ALARM CONTROL SYSTEM [76] Inventor: Ernest J. Buckles, 4604 Moore Rd.,

Middletown, Ohio 45042 [22] Filed: Mar. 22, 1974 [21] Appl. No.: 453,677

[52] U.S. Cl 340/258 R; 340/261; 340/309.4 [51] Int. cl. G08B 13/02 [58] Field of Search 340/3094, 338, 317, 276,

[56] References Cited UNITED STATES PATENTS 2,456,062 12/1948 lwanski 340/266 3,277,249 10/1966 Lyell 200/6 B 3,713,128 1/1973 Wong et a1. 340/261 3,774,190 11/1973 Kyle, Jr 340/261 Primary ExaminerGlen R. Swann, 111 Attorney, Agent, or Firm--Melvi1le, Strasser, Foster & Hoffman [5 7] ABSTRACT The system can be employed to perform a deterrence and warning function in conjunction with any property desired to be protected but is particularly useful in association with unattended property which must be capable of withstanding a limited degree of abuse or disturbance from over-zealous but legitimate users of the property.

16 Claims, 6 Drawing Figures /Z Z/ FAST a /6 SEN eoRs FORWARD /4 /7 20 T1 ME R /6 :NrEeRAToR SWITCHES OUTPUT FUNCTIONS 51.0w 23 REVERSE /5 T1 M ER PATENTED AUG 1 9 I975 saw 1 OF 4 F lllllllll |ll PATENTED AUG 1 9 I975 INTRUSION ALARM CONTROL SYSTEM BACKGROUND OF THE INVENTION This invention relates to an intrusion alarm control system designed to protect persons or property against intrusion, burglery, vandalism, etc., and more particularly, to an intrusion alarm control system which protects individual items of equipment against abuse, vandalism, and attempted entry, in measured degree, by distinguishing between legitimate, wellmeaning customers and the would-be intruder.

There are numerous prior art systems designed to detect an intrusion into a premises and to initiate an alarm in response thereto, such systems being generally limited to simple perimeter detection, such as, for example, by detecting a gross assault and signaling an all-out emergency. These prior art systems exhibit various types of detection means (e.g., mechanical switches, magnetic switches, photoelectric sensors, strips of silver foil, wired mat panels, vibration sensor, etc.) and various warning means (e.g., horns, sirens, lights, television cameras, telephone connections to police headquarters, etc.). See for example, US. Pat. No. 3,634,846. Prior art intrusion systems also often provide a time delay or other suitable means for allowing authorized egress/ingress from the protected area. There are, however, two substantial disadvantages which generally handicap prior art intrusion systems.

With respect to the first of these disadvantages, prior art intrusion alarms generally have no means by which to discriminate between relative levels of abuse. That is, prior art intrusion systems generally have an inherently preset intrusion detection level above which alarm status is assumed and below which the alarm remains dormant. In other words, prior art intrusion systems generally have no ability to discriminate between the severity of various intrusions where the intrusions are all above the systems inherent detection level. This shortcoming directly leads to the second disadvantage generally found in prior art intrusion systems. Since prior art intrusion systems have in general, no ability to discriminate between relative levels of abuse, upon sensing an intrusion above their inherent detection level they all characteristically activate their warning devices simultaneously. That is, there is, in general, no provision for any logical timed sequence in which the various warning functions can be activated but rather, they are all generally initiated simultaneously in hopes, apparently, of immediately attempting to frighten the intruder away. Although the prior art discloses no substantial activation of warnings or alarms in a logically sequential manner so as to reflect the continued severity of the intrusion, the prior art does show a limited use of a timing sequence in a burglar alarm. See for example, US. Pat. No. 2,701,874.

As thus seen, the response of the prior art intrusion system is characteristically total. That is, the prior art control apparatus knows only two conditions: (1 complete dormancy, modified by a delay interval if incorporated, or (2) full alarm status. While the prior art devices afford adequate protection in many situations, they generally lack capability of distinguishing other than the two conditions mentioned. Accordingly, prior art intrusion control systems are used principally as perimeter devices, sensing and responding only to gross entry attempts.

Another, but related, disadvantage generally associated with prior art intrusion control systems is that they often sacrifice sensitivity in favor of reduced vulnerability to false alarms, which results in an annoyance and harassment in the case of legitimate uses of the property. This generally results from either choosing sensors which respond only to disturbances of relatively high magnitude or introducing a delay into the protective circuit, allowing'small and/or short disturbances to go undetected.

As a result of these disadvantages prior art intrusion control systems have been relatively ineffective in protecting property which must be capable of withstanding a certain level of abuse without initiating an alarm.

SUMMARY OF THE INVENTION The present invention provides an intrusion alarm control system which can discriminate between relative levels of abuse and has the ability to initiate a logically timed sequential activation of warnings and alarms in a manner reflecting the present severity of the intrusion. The present invention also provides an intrusion alarm control system which is both highly sensitive and subject to minimal probability of false alarm.

The intrusion alarm control system of the present invention essentially comprises one or more sensors mounted on the property to be protected, a fast forward timer mechanism controlled partially by inputs from the sensors and partially by internal functions, a slow reverse timer whose function is to generate a reference signal, an integrator which is utilized to combine the outputs of the two aforementioned timers, a plurality of switches actuatable by timing outputs from the integrator and a plurality of output functions associated with the plurality of switches.

The operation of the control system can briefly be described as follows. The sensors, when triggered or actuated, transmit electrical signals which initiate the fast forward timer mechanism to an extent proportional to the severity of the intrusion as detected by the sensors. The output of the fast forward timer mechanism is fed to the integrator which in turn controls the plurality of switches. Simultaneously with initiation of the fast forward timer mechanism, the slower reverse timer, which is driven by internal power and whose output is also fed to the integrator, is initiated by one of the plurality of integrator controlled switches. If, during a preselected interval, defined by a predetermined intrusion impulse level (force multiplied by time) the intrusion has terminated, the reverse timer will, at a rate porportional to the speed of the reverse timer, cause the system to reset itself to its pre-intrusion alert status. During this time no alarms or warnings have been activated, thus providing for a predetermined level of authorized abuse to the property. However, if the intrusion continues beyond the aforementioned preselected impulse level, a first warning will be initiated by one of the plurality of integrator controlled switches. Upon continuation of the intrusion optional numbers and types of secondary warnings may similarly be initiated by an appropriate number of the plurality of integrator controlled switches. Should the intrusion continue dispite these warnings, a co-called trip point is reached wherein one of the plurality of integrator controlled switches causes the fast forward timer to be driven at full speed directly from internal power in lieu of from sensor output signals. Once this trip point has been reached,

automatic resetting of the control system by the slow reverse timer is no longer possible because the system is thereafter entirely controlled by internal functions. The fast forward timer will be driven at full speed by internal power for a predetermined length of time denominated the fast forward portion of the main alarm interval. At precisely controllable points within this fast forward portion of the main alarm interval, the integrator controlled switches actuate various alarm, warning or monitoring output functions and cause the slow reverse timer to reverse polarity, wherein it imparts forward input to the integrator additive to the input of the fast forward timer. After the predetermined fast forward portion of the main alarm interval has been completed, one of the plurality of integrator controlled switches will deactivate the fast forward timer so that thereafter the integrator will be driven in a forward direction at the relatively slow rate of the reverse timer. After a final predetermined period of time the reverse timer is deactivated by one of the plurality of integrator controlled switches and the control system is thereby reset to its pre-intrusion condition.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a functional block diagram showing the alarm system of the present invention.

FIG. 2 is a functional block diagram showing a preferred embodiment of the alarm control system of the present invention.

FIG. 3 is a fragmentary cross-sectional view of the electro mechanical embodiment of the alarm control system shown in FIG. 2.

FIG. 4 is a wiring diagram of the embodiment of the alarm control system shown in FIGS. 2 and 3.

FIG. 5 is an electrical circuit diagram of one embodiment of the amplifier shown in FIGS. 3 and 4.

FIG. 6 is a typical timing diagram of the alarm control system of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to a consideration of the details of the present invention, it will be seen from FIG. 1 that the input to the control system is provided by a plurality of sensors, generally indicated at 10, directly affixed to the surface of the property to be protected. The output of sensors 10 is fed, via line 11, to a fast forward timer 12. The output 13 of fast forward timer 12 is applied to integrator 14, which controls the operation of a plurality of switches, generally indicated at 16, through control line 15. The plurality of switches 16 in turn applies appropriate control signals to the output functions 20, a slow reverse timer l8, and the fast forward timer 12, through respectively, control lines 17, 19 and 21. The output of the slow reverse timer 18 is applied to the integrator 14 as at 23 in a manner similar to the application of the output 13 of the fast forward timer 12 to the integrator 14.

When an intrusion is attempted, sensors 10 will transmit an electrical signal through line 1 1 causing fast forward timer 12 to respond with an output signal proportional to the impulse reflecting the severity of the intrusion. Simultaneously with actuation of fast forward timer 12, one of the plurality of switches 16 initiates slow reverse timer 18. The output of slow reverse timer 18 is applied to integrator 14 at a constant rate, substantially slower and in a direction reverse to that being imparted integrator 14 from fast forward timer 12. Because inputs to integrator 14 from fast forward timer 12 are dependent upon continued disturbance of sensors 10, it can be seen that slow reverse timer 18, is functioning as an automatic resetting means.

It will be noted that up to a preselectable point representing maximum authorized abuse, no warning signals have been activated, and slow reverse timer l8 continuously drives the system towards its initial reset position. However, if the intrusion continues, as determined by further impulse accumulation at fast forward timer 12, various warning signals, as shown at 20, are initiated when a respective number of the plurality of switches 16 are activated by appropriate timing signals from integrator 14. Slow reverse timer 18 will, up to and including the interval of the last warning 20, cause the control system to automatically reset itself to its preintrusion condition.

Should impulse accumulation by fast forward timer 12 continue beyond the interval of the last warning, the socalled trip point of the timing cycle is reached. At this point, one of the plurality of switches 16 causes fast forward timer 12, by a signal through line 21, to be driven at full speed directly from internal power. Once this trip point has been reached, automatic resetting of the control system by slow reverse timer 18 is no longer possible since the input to integrator 14 from fast forward timer 12 is no longer dependent upon continued intrusion at sensors 10 but rather, is entirely controlled by internal functions. After the trip point, fast forward timer 12 will be driven at full speed, by internal power, for a preselectable length of time called the fast forward portion of the main alarm interval.

Since the fast forward timer 12, during the fast forward portion of the main alarm interval, is operating at full speed, precise programming of further switch actuations is possible. Thusly, at precisely controllable points within the fast forward portion of the main alarm interval, the integrator 14 controlled plurality of switches 16 actuates various alarm, warning or monitoring output functions 20 and, through a signal on line 19, causes slow reverse timer 18 to reverse polarity, wherein it imparts forward input timing singals to integrator l4 additive to the input of fast forward timer 12. After the fast forward portion of the main alarm interval has been completed, one of the plurality of switches 16 will deactivate fast forward timer 12 so that thereafter integrator 14 will be driven in a forward direction at the relatively slow rate of slow reverse timer 18. Deactivation of slow reverse timer 18 by another one of the plurality of switches 16 will define the termination of one complete timing cycle of the alarm control systern.

FIG. 2 discloses a block diagram of a preferred embodiment of the alarm control system of the present invention which incorporates an electromechanical mode of operation. It has been discovered that an electromechanical mode of operation affords many benefits due to its inherent reliability (ruggedized construction can be conveniently provided for) and its compatibility with existing alarms and components.

It will be seen from FIG. 2, wherein like numerals have been used to describe corresponding functions with respect to FIG. 1, that fast forward timer 12 has been replaced by proportional servomotor 12a and rapid advance motor 12b. Similarly, slow reverse timer 18 has been replaced by reference servomotor 18a and slow advance motor 18b. It will be understood that the combination of proportional servomotor 12a and rapid advance motor 12b provide the same capability as fast forward timer 12 and that the combination of reference servomotor 18a and slow advance motor 18b provide the same capability as slow reverse timer 18. It will likewise be seen from FIG. 2 that integrator 14 has been replaced by mechanical integrator 14a and that the plurality of switches 16 has been replaced by a plurality of mechanically operated switches and a camshaft mechanism as generally indicated at 16a. Finally, it will be noted that amplifier 22 is shown intermediate sensors and proportional servomotor 12a, being connected to sensors 10 by line and to proportional servomotor 12a by line 11.

An examination of FIG. 2 will further disclose that outputs 13a, 13b, 23a and 23b from, respectively, proportional servomotor 12a, rapid advance motor 12b, reference servomotor 18a and slow advance motor 18b, are applied directly to mechanical integrator 14a. It will similarly be noted that outputs 19a, 19b and 21 from the camshaft and switch assembly 16a are utilized, respectively, to control reference servomotor 18a, slow advance motor 18b and rapid advance motor 12b.

A detailed description of the operation of the preferred embodiment of the invention, as generally depicted in FIG. 2, will now be undertaken with specific reference to FIGS. 3 and 4 wherein, FIG. 3 shows the electromechanical configuration and FIG. 4 shows the electrical wiring diagram of the embodiment of the invention generally shown in FIG. 2. Although as shown in FIGS. 3 and 4, the function of proportional servomotor 12a and rapid advance motor 12b are performed by a single servomotor 120, it will be understood that this is an optional feature, shown for purposes of illustration only. Similarly, the functions of reference servomotor 18a and slow advance motor 18b are shown as being performed by single servomotor 18c.

With respect to FIG. 3, it will be seen that a transducer 10 is mounted at strategic point on the property 9 to be protected. The output signals from transducer 10 are fed to amplifier 22, which is an optional item in the circuitry of the invention, through conductors 25a and 25b. D. C. energization of amplifier 22 is accomplished as shown at conductors 26 and 27. The output of amplifier 22 is fed to the alarm control system through conductor 28 and cam switch 29. Cam switches 29 and 32 are single pole, two position switches whereas cam switch 31 is a single pole, multiple position switch. Cam switch 30 is double pole, three position, center off switch. Cam switches 29, 30, 31 and 32 are actuatable by cam surfaces 33, 34, 35 and 36, respectively, which are rotatably affixed to camshaft 37.

When cam switch 29 is in its normal pre-alarm position, electrically engaging contact 38, the output of amplifier 22 is fed through conductor 28 and cam switch 29, whereupon it is applied by conductor 41 to gearhead servomotor 12c through rheostat 42. Conversely, when camswitch 29 electrically engages contact 39, internal D. C. power is applied to cam switch 29 from conductor 43 and applied to gearhead servomotor 120 through conductor 41 and rheostat 42. Conductor 45 makes electrical connection with node 44 between rheostat 42 and cam switch 29 so as to energize solonoid brake 46 in the same manner as gearhead servomotor is energized. Solenoid brake 46 is connected to negative D. C. potential as shown at 47 and to fly wheel 48.

The output of gearhead servomotor 120 is coupled to gear differential mechanism 14b through shaft 49. Shaft 49 is terminated in fly wheel 48 at its other end. Negative D. C. potential is applied through conductor 50 to the other input terminal of gearhead servomotor 120.

Another gearhead servomotor 18c also provides an input to gear differential 14b through shaft 51. The positive input of gearhead servomotor is connected by conductor 52 to cam switch 30. The remaining terminal of gearhead servomotor 180 is connected through rheostat 53 and conductor 54 to cam switch 30. With cam switch 30 in its deactivated position (as shown in FIG. 3), no power will be supplied to gearhead servomotor 180 and it will therefore impart no rotational forces to gear differential mechanism 14b. However, when cam switch 30 is actuated by cam surface 34 causing electrical engagement of conductor 52 with contact 55, negative D. C. potential will be applied by conductor 56 to conductor 52. Simultaneously, actuation of cam switch 30 causes electrical engagement of conductor 54 with contact 57 whereby positive D. C. potential is applied from conductor 43 to conductor 54, this voltage being impressed upon gearhead servomotor l8c through rheostat 53 so that a rotational force reverse to that supplied by gearhead servomotor 120 will be imparted gear differential mechanism 14b through shaft 51.

As previously indicated, cam switch 31, which is a single pole multiposition switch, may be actuated by cam surface 35 to sequentially activate a series of warning signals. Similarly, cam switch 32 may be actuated by cam surface 36 to activate a main alarm. Support member 59 is provided to mechanically support and enclose the various components of the alarm control system.

The operation of the alarm control system of FIG. 3 is as follows. An attempted intrusion or entry into protected property 9 causes transducer 10 to output electrical signals through conductors 25a and 25b proportional to the intrusion. The intrusion signal is amplified by amplifier 22 and applied to gearhead servomotor 120 through conductor 28, cam switch 29 (This switch making connection with contact 38), conductor 41 and rheostat 42. As a result of this input, gearhead servomotor l2c will impart a rotational force to gear differential mechanism 14b through shaft 49 which, in turn, produces a rotation of cam shaft 37 proportional to the severity of the intrusion, since the response of gearhead servomotor 126 is proportional to impulse. Upon initiation of angular rotation of cam shaft 37, cam surface 34 actuates cam switch 30. This causes positive D. C. potential to be applied to the lower terminal of gearhead servomotor 18c through cam switch 30 (the switch making connection with contact 55 and 57), conductor 54 and conductor 52, thereby causing gearhead servomotor 180 to rotate in a direction reverse that of gearhead servomotor 120. The reverse rotation of gearhead servomotor 180 is applied to gear differential mechanism 14b through shaft 51 so that an opposite rotation as that caused by servomotor 120 will be imparted to cam shaft 37. The reverse rotational forces being imparted to the gear differential mechanism 14b by gearhead servomotor 180 are at a constant angular velocity nominally slower than the rotational forces being applied to gear differential mechanism 14b by gearhead servomotor 12c when the latter is energized through outputs 25a and 25b originating at transducer 10. Thus, if the intrusion sensed by transducer 10 is of a continuing type, the rotational forces applied to gear differential mechanism 14b by gearhead servomotor 120 will supersede the reverse rotational forces being applied to gear differential mechanism 14b by gearhead servomotor 18c, thereby causing cam shaft 37 to rotate in a positive angular direction. On the other hand, if the intrusion sensed at transducer 10 is of a slight level and short duration, the reverse rotational forces imparted gear differential mechanism 14b by gearhead servomotor 180 will dominate over forward forces imparted to gear differential mechanism 14b by gearhead servomotor 12c, thereby causing cam shaft 37 to rotate in a reverse angular direction and cam surfaces 33 and 34 to reset cam switches 29 and 30 to their pre-intrusion or normal positions.

Fly wheel 48 provides a smoothing action without which the armature assembly of servomotor 12c developes insufficient inertial energy to accurately reflect impulse. Solenoid brake 46 is energized in parallel with servomotor 12c in a direction so as to reduce brake friction during accelleration; adjustment of braking force serves to compensate for wear, power source variation, and performance differences between gearhead servomotors 18c and 120. Further calibration of gearhead servomotor response is provided by gain adjustment of amplifier 22, and by rheostats 42 and 53 in series with the armature of each gearhead servomotor.

Should the intrusion continue or be of sufficient severity so that the forward rotational forces imparted to gear differential mechanism 14b by gearhead servomotor 12c continue to dominate over the constant reverse rotational forces imparted by gearhead servomotor 18c, cam shaft 37 will, at a predetermined point, cause cam surface 35 to sequentially actuate cam switch 31 to initiate a series of warning signals. The duration of the warning signals is variable, depending upon the extent of rapid advance imparted by gearhead servomotor 12c integrated with the counter-effort imparted by gearhead servomotor 18c. Prior to and during this warning interval, forward angular rotation of cam shaft 37 is entirely dependent upon output signals from transducer 10 energizing gearhead servomotor 12c. Therefore, if the intrusion ceases, gearhead servomotor 18c will still be capable of causing reverse angular rotation of cam shaft 37, thereby causing cam surfaces 33, 34 and 35 to reset cam switches 29, 30, and 31 to their original preintrusion or normal condition. However, should intrusion continue beyond a predetermined level of impulse in excess of that necessary for cam switch 31 to activate the various warning signals, cam surface 33 will cause switch 29 to electrically engage contact 39, whereupon gearhead servomotor 120 will thereafter be driven by internal D. C. power through conductor 43. This is known as the trip point after which the control system cannot be reset to its original pre-intrusion or normal condition by gearhead servomotor 18c.

After the trip point has been reached, gearhead servomotor 12c is driven at full speed by internal power for a predetermined length of time controllable by the operation of cam surface 33 and cam switch 29. The predetermined length of time is denominated the fast forward portion of the main alarm interval. Due to the fast full forward speed of gearhead servomotor 12c during the predetermined length of time, actuation of cam switches 29, 30 and 32 by their respective cam surfaces 33, 34 and 36 is precisely controllable with respect to time. Thus, at precisely controllable points within the fast forward portion of the main alarm interval, cam surface 36 causes cam switch 32 to activate, in a sequential manner or otherwise, various main alarm warnings. Also, within the fast forward portion of the main alarm interval, cam surface 34 causes cam switch 30 to make connection with contacts 55 and 58, thereby reversing the polarity of servomotor 180. The reversal of polarity of gearhead servomotor 180 causes it to impart rotational forces to gear differential mechanism 14b in a forward direction which are additive to those forces being imparted to gear differential mechanism 14b by gearhead servomotor 12c. Following expiration of the fast forward portion of the main alarm interval, cam surface 33 will cause cam switch 29 to deactivate gearhead servomotor 12c to its preintrusion or normal position by again making connection with contact 38, whereupon cam shaft 37 will be driven in a forward direction at a relatively slow speed by the effect of gearhead servomotor 18c. After a final predetermined length of time, cam surface 34 will cause cam switch 30 to deactivate gearhead servomotor 180 to its pre-intrusion level, thereby causing cam shaft 37 to cease rotating and to reset the entire control system to its pre-intrusion or normal condition.

FIG. 4 shows a typical wiring diagram which may be used in conjunction with the control system as described with respect to FIGS. 2 and 3. As can be seen, a plurality of transducers, generally indicated at 10a, 10b, 10c and 10d, are employed corresponding to the unitary transducer 10 as described in connection with FIG. 3. A disturbance at one or more of transducers- 10a, 10b, 10c and 10d results in a signal transmission to amplifier 22 by conductors 25a and 25b. The amplified signal is applied through conductor 28 and rheostat 42 to gearhead servomotor which drives cam shaft 37 through gear differential mechanism 14b, thereby accellerating fly wheel 48. Simultaneously, brake solenoid 46 is energized to release fly wheel 48. Cam shaft 37 actuates cam switches 61 through 71, which correspond to cam switches 29, 30, 31 and 32 of FIG. 3, and other optional switches as follows. At some predetermined position of cam shaft 37, cam switch 61 turns on gearhead servomotor by causing a connection to be made with contact 72. Gearhead servomotor 180 causes reverse rotational forces to be applied to cam shaft 37, thus attempting to reset the system, but at a substantially slower rate than the forward forces being applied by gearhead servomotor 12c. Each time gearhead servomotor 12c is energized, the exemplary camera solenoid 73 is energized through switches 64 and 74, exposing one or several frames of movie film. This is a tell-tale feature, for optional use with the control system but very useful for record purposes in cases of repeated harassment type offenses. After sufficient travel of cam shaft 37 the first warning 20a is activated by cam switch 62. Cam switch 63 activates the next warning device which is, in this example, a remote signal. The remote signal 20b, e.g., a latching relay, can be reset by means of a manual push button switch 76 which momentarily reverses polarity. Next, cam switch 66 activates a final warning device 200. Gearhead servomotor 180 is still operating in a reverse direction, and is still capable of resetting the control system to its preintrusion or normal condition provided that the motors reverse speed is not being dominated by the input from gearhead servomotor 12c. Actuation of cam switch 64, wherein connection is made to contact 78, is the trip point to full alarm status as described above. Gearhead servomotor 120 will now draw power directly from the source through cam switch 64 and switch 79 advancing cam shaft 37 at full speed through a predetermined portion of the alarm cycle.

As previously indicated, within the fast travel period, on-off timing of remaining output functions may be set with precision. During the main alarm cycle, cam switch 65 is closed so as to short circuit transducers a, 10b, 10c and 10d, preventing interference with the operation of gearhead servomotor 120. At some predetermined point in the fast forward portion of the main alarm interval, cam switch 61 is actuated so as to reestablish connection with contact 80, thereby turning off gearhead servomotorl8c. Thereafter, cam switch 67 is actuated, so as to make connection with contact 83,

thereby reversing polarity of gearhead servomotor 180, which will then drive cam shaft 37 forward, additive to the motion imparted by gearhead servomotor 12c. Also, during the fast forward portion of the main alarm interval, cam switches 68, 69, 70 and 71 are activated in some sequential manner so as to actuate the various main alarm output functions d, 20e, 20f and 20g.

After the main alarm output functions have been actuated, cam switch 64 remakes connection with contact 81, thereby deenergizing gearhead servomotor 12c. Cam switch 65 is meanwhile maintained in its closed position to insure that a damaged transducer will not continue to drive gearhead servomotor 12c through amplifier 22. Gearhead servomotor 18c at this point becomes the driver, advancing cam shaft 37 rotationally forward at its fixed, relatively slow speed. Choice of the gearhead servomotor 12c de-energization point fixes the remaining length of the cycle, thereby determining the total operating time for any function beyond the fast forward interval.

Push button switch 82 provides a capability for rapid advancement of cam shaft 37 to its original preintrusion position when it is desirable to terminate an alarm disturbance sooner than a programed interval. Rapid advancement of camshaft 37 is accomplished by driving gearhead servomotor 12c directly from internal power through switch 82. Switch 79 is provided for convenience in the precise setting of cam surfaces in the fast forward sector by including the capability of stopping and holding cam shaft 37 at any desired position. Switch 84 is a multiple pole, two position switch 'which allows for switching output functions 20a, 20b,

20c, 20d, 20e, 20f and 20g to indicator lights 20aa, 20bb, 2000, 201141, 20ee, 20ff, and 20gg, for testing or adjustment purposes, without disturbance of actual alarm functions.

As previously indicated, the use of amplifier 22 is optional. The necessity for, and type of, amplification means used, will depend to a great extent upon the type 'of transducers used. Where low level transducers are {used, e.g., accelerometers, thermocouples, motion detectors, echo detectors, and the like, high amplification means may be required. Many well known amplifiers are available for use with transducers of this type. It has been found that passive transducers, i.e., those exhibiting an increase in resistance is response to a disturbance, provide adequate results in most situations.

FIG. 5, which is orientated to the wiring diagram of FIG. 4, shows an exemplary amplifier 22a which may be used in conjunction with passive transducers. The amplifier 22a comprises a silicon controlled rectifier (SCR) 85, a rheostat 86 and a bias adjustment resistor 87, power to the circuit being supplied in the form of pulsating D. C. from a source such as a full wave rectifier. The rheostat 86 provides adjustment capabilities to compensate for differences in transducers, and the bias adjustment resistor 87 provides capability to adjust the firing voltage of the SCR 85. SCR is biased, by the volatge impressed across transducers 10a, 10b, 10c, and 10d, to just under firing voltage. A small increase in transducer resistance, resulting from an attempted intrusion, will trigger SCR 85, thereby energizing the gearhead servomotor 12c.

Referring to FIG. 6, an exemplary program graph for the alarm control system described herein is shown. As the precise timing of events by the system is within the discretion of the operator, by altering the various cam surfaces, this program graph is presented for illustration purposes only. It will be noted, as hereinbefore described, that gearhead servomotor 120 may advance a preset amount before the first warning is actuated. The free period represents an interval equivalent to an authorized or acceptable level of intrusion. The free period is provided even though accumulation of impulse by gearhead servomotor 12c is begun prior to the initiation of any warnings.

The ability to discriminate between relative levels of abuse is one of the distinct advantages of the control system of the present invention. Another important advantage of the invention over the prior art is its ability to logically, and in a sequential manner, control the operation of various monitoring, warning and alarm functions. The capability of providing several distinct cam shaft rotational velocities within one complete timing cycle, which is provided by the arrangement of two controllable inputs (which can be applied separately or combined additively or subtractively), makes possible a high degree of accuracy for programing the various output function responses during the cycle.

Another improvement over prior art intrusion control systems is the inclusion of various tell-tale means. These means, which are activated by alarm activity, provide enduring evidence of some abuse of the property being protected, making possible appropriate investigation into possible damage. This function is provided by a circular dial 88 and two coincident shaft pointers 89 and 90 separated from the circular dial 88 I by spring washer 91. The primary pointer 90 is mechanically connected to the cam shaft 37 as at connection 92, thereby indicating cam shaft position at any given moment in the system cycle. The tell-tale pointer 89 is arranged as a maximum reading type pointer, responding only to drive in the forward direction by means of a projecting tab 93 engaging the primary pointer 90. When the primary pointer 90 retreats, it

.through cam switch 64 and switch 74. One or several frames are exposed with each separate signal from a transducer providing a valuable record of an intrusion for investigation and study purposes.

It will, of course, be understood that the description herein of the preferred embodiment of the invention is intended as exemplary only and not to impose any limitations on the invention. It is, therefore, within the scope of the invention to use any kr wn mechanism which can function as a timer to provide the capabili ties of the fast forward timer l2 and the slow reverse timer 18 shown in FIG. 1. Examples of such could be either a digital electronic counter or an electromechanical motor. Similarly, the integrator 14 shown in FIG. 1 could be an electronic device, a mechanical device, e.g. a gear differential, or any other mechanism which can perform an integration function. The plurality of switches indicated at 16 in FIG. 1, likewise could comprise any of a number of well known switches including solid state electronic switches or mechanical cam type operated switches. Furthermore, the type of sensor 10 and the type of output functions 20 utilized in the invention could comprise any of a number of well known sensors and output functions depending upon the particular type and degree of protection desired. For example, the sensors 10 may include vibration sensors, temperature sensors, smoke sensors, chemical sensors and various other types of transducers. Similarly, the output functions may include sirens, horns, bells, lights, audio recorders and still or movie cameras.

Modifications may be made in the invention without departing from the spirit of it.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An intrusion alarm control system for protecting property against intrusion comprising:

a. at least one sensor associated with said property for producing an output signal in response to an intrusion;

b. timing means having first and second inputs, said first timing means input being connected to said sensor, said timing means producing first and second groups of sequential, preselected timing signals defining, respectively, first and second timing cycle portions, wherein said first group of preselected timing signals are reversibly produced in response to said output signal from said sensor at a rate reflecting the severity of said intrusion, and said sec ond group of preselected timing signals are irreversibly produced in response to a signal at said second input of said timing means;

a plurality of switches each having an input and an output, said inputs of said switches being connected to said timing means, and a first one of said switches having its output connected to said second timing means input, each of said switches being actuatable by at lease one of said preselected timing signals of at least one of said groups, said first switch being actuatable by the last one of said preselected timing signals of said first group, whereby, actuation of said first switch causes said timing means to initiate production of said second group of sequential preselected timing signals; and d. a plurality of output functions each connected to one of said outputs of one of said switches other than said first switch, each of said output functions being activated upon actuation of its respective one of said switches.

2. The intrustion alarm control system according to claim 1, wherein said timing means includes means for causing, during said first timing cycle portion, the production of said first group of sequential preselected timing signals to advance in a direction towards the completion of said timing cycle portion whenever the severity of said intrustion is above a predetermined threshold level and, to otherwise recede in a direction opposite thereof whereupon said timing means is reset to its pre-intrusion condition.

3. The intrustion alarm control system according to claim 1, wherein said timing means comprises:

a. fast forward timing means for generating, during said first timing cycle portion, a first series of timing signals in proportion to the impulse and, at a rate reflecting the instantaneous disturbance force, sensed by said sensor during intrusion against said property, and, during said second timing cycle portion, a second series of timing signals at a first predetermined constant rate and in the same direction as said first series of timing signals;

b. slow reverse timing means for generating, during said first timing cycle portion, a third series of timing signals at a second predetermined constant rate and in a direction reverse to that of said first series of timing signals and, during said second timing cycle portion, a fourth series of timing signals at a third predetermined constant rate and in the same direction as said first series of timing signals; and integration means for combining said first and second series of timing signals from said fast forward timing means with said third and fourth series of timing signals from said slow reverse timing means and developing therefrom an integrated output signal comprising said first and second groups of sequential, preselected timing signals, wherein said first group of signals comprise preselected ones of the combination of said first and third series of timing signals and said second group of signals comprises preselected ones of the combination of said second and fourth series of timing signals.

4. The intrustion alarm control system according to claim 3, wherein said plurality of switches includes a second switch having its output connected to said slow reverse timing means, the activation of said second switch causing said slow reverse timing means to transistion from producing said third series of timing signals to producing said fourth series of timing signals and, said first switch having its output connected to said fast forward timing means.

5. The intrusion alann control system according to claim 3, wherein said timing means includes means for causing said rate of generation of said first series of timing signals to exceed said rate of generation of said third series of timing signals whenever the severity of said intrusion is above a predetermined threshold level.

6. The intrusion alarm control system according to claim 3, wherein said plurality of switches includes a third switch having its output connected to said slow reverse timing means, the activation of said third switch causing said slow reverse timing means to initiate generation of said third series of timing signals.

7. The intrustion alarm control system according to claim 3, wherein said fast forward timing means comprises:

a. a proportional servo means in communication with said sensor, the output of said servo means comprising said first series of timing signals; and

b. a rapid advance timing means whose output comprises said second series of timing signals.

8. The intrusion alarm control system according to claim 7, wherein said proportional servo means comprises a first gearhead servomotor and said rapid advance timing means comprises a second gearhead servomotor.

9. The intrustion alarm control system according to claim 7, wherein said proportional servo means and said rapid advance timing means comprise a single gearhead servomotor.

10. The intrustion alarm control system according to claim 3, wherein said slow reverse timing means comprises:

a. a reference servo means whose output comprises said third series of timing signals; and

b. a slow advance timing means whose output comprises said fourth series of timing signals.

11. The intrusion alarm control system according to claim 10, wherein said reference servo means comprises a first gearhead servomotor and said slow advance timing means comprises a second gearhead servomotor.

12. The intrusion alarm control system according to claim 10, wherein said reference servo means and said slow advance timing means comprise a single gearhead servomotor.

13. The intrusion alarm control system according to claim 3, wherein said integration means comprises a differential gear assembly, a camshaft operatively connected thereto, and a plurality of cam surfaces operatively engaging said camshaft, said differential gear assembly having in association therewith two input shafts,

one of said input shafts being in communication with said fast forward timing means, for applying said first and second series of timing signals to said differential gear assembly, and the other of said input shafts communicating with said slow reverse timing means, for applying said third and fourth series of timing signals to said differential gear assembly, each of said cam surfaces communicating with at least one of said switches.

14. The intrusion alarm control system according to claim 13, wherein each one of said switches comprises a cam switch.

15. The intrusion alarm control system according to claim 3, wherein amplifier means is located intermediate and in communication with said sensor and said fast forward timing means.

16. The intrusion alarm control system according to claim 13, wherein tell-tale means is associated with said camshaft, said tell-tale means comprising a circular dial in fixed relation to said camshaft, a primary pointer rotatably affixed to said camshaft, said primary pointer including a tab projecting therefrom, said primary pointer adapted to, in association with said circular dial, indicate the angular position of said camshaft, and a tell-tale pointer cooperative with said primary pointer and responding only to forward rotation of said camshaft by means of said tab projecting from said primary pointer, thereby indicating, in association with said circular dial, maximum forward rotation of said camshaft.

Claims (16)

1. An intrusion alarm control system for protecting property against intrusion comprising: a. at least one sensor associated with said property for producing an output signal in response to an intrusion; b. timing means having first and second inputs, said first timing means input being connected to said sensor, said timing means producing first and second groups of sequential, preselected timing signals defining, respectively, first and second timing cycle portions, wherein said first group of preselected timing signals are reversibly produced in response to said output signal from said sensor at a rate reflecting the severity of said intrusion, and said second group of preselected timing signals are irreversibly produced in response to a signal at said second input of said timing means; c. a plurality of switches each having aN input and an output, said inputs of said switches being connected to said timing means, and a first one of said switches having its output connected to said second timing means input, each of said switches being actuatable by at lease one of said preselected timing signals of at least one of said groups, said first switch being actuatable by the last one of said preselected timing signals of said first group, whereby, actuation of said first switch causes said timing means to initiate production of said second group of sequential preselected timing signals; and d. a plurality of output functions each connected to one of said outputs of one of said switches other than said first switch, each of said output functions being activated upon actuation of its respective one of said switches.

2. The intrustion alarm control system according to claim 1, wherein said timing means includes means for causing, during said first timing cycle portion, the production of said first group of sequential preselected timing signals to advance in a direction towards the completion of said timing cycle portion whenever the severity of said intrustion is above a predetermined threshold level and, to otherwise recede in a direction opposite thereof whereupon said timing means is reset to its pre-intrusion condition.

3. The intrustion alarm control system according to claim 1, wherein said timing means comprises: a. fast forward timing means for generating, during said first timing cycle portion, a first series of timing signals in proportion to the impulse and, at a rate reflecting the instantaneous disturbance force, sensed by said sensor during intrusion against said property, and, during said second timing cycle portion, a second series of timing signals at a first predetermined constant rate and in the same direction as said first series of timing signals; b. slow reverse timing means for generating, during said first timing cycle portion, a third series of timing signals at a second predetermined constant rate and in a direction reverse to that of said first series of timing signals and, during said second timing cycle portion, a fourth series of timing signals at a third predetermined constant rate and in the same direction as said first series of timing signals; and c. integration means for combining said first and second series of timing signals from said fast forward timing means with said third and fourth series of timing signals from said slow reverse timing means and developing therefrom an integrated output signal comprising said first and second groups of sequential, preselected timing signals, wherein said first group of signals comprise preselected ones of the combination of said first and third series of timing signals and said second group of signals comprises preselected ones of the combination of said second and fourth series of timing signals.

4. The intrustion alarm control system according to claim 3, wherein said plurality of switches includes a second switch having its output connected to said slow reverse timing means, the activation of said second switch causing said slow reverse timing means to transistion from producing said third series of timing signals to producing said fourth series of timing signals and, said first switch having its output connected to said fast forward timing means.

5. The intrusion alarm control system according to claim 3, wherein said timing means includes means for causing said rate of generation of said first series of timing signals to exceed said rate of generation of said third series of timing signals whenever the severity of said intrusion is above a predetermined threshold level.

6. The intrusion alarm control system according to claim 3, wherein said plurality of switches includes a third switch having its output connected to said slow reverse timing means, the activation of said third switch causing said slow reverse timing means to initiate generation of said third series of timing signals.

7. The intrUstion alarm control system according to claim 3, wherein said fast forward timing means comprises: a. a proportional servo means in communication with said sensor, the output of said servo means comprising said first series of timing signals; and b. a rapid advance timing means whose output comprises said second series of timing signals.

8. The intrusion alarm control system according to claim 7, wherein said proportional servo means comprises a first gearhead servomotor and said rapid advance timing means comprises a second gearhead servomotor.

9. The intrustion alarm control system according to claim 7, wherein said proportional servo means and said rapid advance timing means comprise a single gearhead servomotor.

10. The intrustion alarm control system according to claim 3, wherein said slow reverse timing means comprises: a. a reference servo means whose output comprises said third series of timing signals; and b. a slow advance timing means whose output comprises said fourth series of timing signals.

11. The intrusion alarm control system according to claim 10, wherein said reference servo means comprises a first gearhead servomotor and said slow advance timing means comprises a second gearhead servomotor.

12. The intrusion alarm control system according to claim 10, wherein said reference servo means and said slow advance timing means comprise a single gearhead servomotor.

13. The intrusion alarm control system according to claim 3, wherein said integration means comprises a differential gear assembly, a camshaft operatively connected thereto, and a plurality of cam surfaces operatively engaging said camshaft, said differential gear assembly having in association therewith two input shafts, one of said input shafts being in communication with said fast forward timing means, for applying said first and second series of timing signals to said differential gear assembly, and the other of said input shafts communicating with said slow reverse timing means, for applying said third and fourth series of timing signals to said differential gear assembly, each of said cam surfaces communicating with at least one of said switches.

14. The intrusion alarm control system according to claim 13, wherein each one of said switches comprises a cam switch.

15. The intrusion alarm control system according to claim 3, wherein amplifier means is located intermediate and in communication with said sensor and said fast forward timing means.

16. The intrusion alarm control system according to claim 13, wherein tell-tale means is associated with said camshaft, said tell-tale means comprising a circular dial in fixed relation to said camshaft, a primary pointer rotatably affixed to said camshaft, said primary pointer including a tab projecting therefrom, said primary pointer adapted to, in association with said circular dial, indicate the angular position of said camshaft, and a tell-tale pointer cooperative with said primary pointer and responding only to forward rotation of said camshaft by means of said tab projecting from said primary pointer, thereby indicating, in association with said circular dial, maximum forward rotation of said camshaft.

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