CA1110342A - Keyless entry system - Google Patents

Abstract

Abstract of the Invention A keyless system especially useful in controlling the doors and trunk of an automobile is disclosed. The overall system usually comprises an input station containing a key-board, a signal processor, signal amplification means and an electromechanical grouping which converts the electrical output from the amplifier to mechanical movement in control of a lock. The system is activated by a touch control at the input keyboard and with the power section of the system energized, the lock is controlled in response to a proper sequence of digital input signals created by the operator.
The input at the control station is described in terms of a keyboard having five selectors and resulting in approxi-mately three thousand possible combinations for the base code. The signal processor responds to correct combinations of digital inputs with a drive signal. The signal processor is also programable with temporary convenience codes which are loaded into the logic portion of the system with access preconditioned on entry of the base code.

Description

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BACKGROUND OF THE INVENTION
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Field of the Invention - The present invention relates to controlled access and more particu]arly to systems which are operable without a key and are especially adaptable for application in vehicles such as automobiles. -~
Description of the Prior Art ~ After automobiles gained general acceptance by the consuming public, mechanisms were -devised for the purpose of limiting their closure and opera-tion. The conventional key operated tumbler lock was readily available for such applications as doors,glove boxes, trunks and ignitions on automobiles, although security devices ;~
operable without a key were soon being sought.
One such system is described in United States Patent 1,251,365 entitled Permutation Lock which involves relatively complicated interlock mechanisms using electromagnets to position tumblers in a bolt which controls the movement of a mechanical component intended to be locked The system is button operated and the buttons must be pushed in a prese-lected sequential order for operation. The system is con-sidered mechanically complex, heavy and bulky and is generally ;
unsuited for many current day automobile applications.
In United States Patent 1,2989177 entitled Combination Lock for Automobiles, the inventors describe a somewhat analogous system using a plurality of interchangeable keys having selected areas of conducting and nonconducting sur-faces thereon such that when the keys are mechanically adjusted by the operator to a prearranged disposition, _,, _ various electrical circuits are completed and the interlock is bypassed. Another very old system is described in United States Patent 1,587,75i entitled Automobile Lock which is electromechanical in nature and is operable by properly in-serting a plug into one of a plurality of receptacles and manipulating the position of the plug. The concepts in each of these two patents are feasible but impractical by current day standards because of their size, complexity and relatively inflexible codeability.
More recent variations of the relatively cumbersome locking systems described above are disclosed in United States Patent 2,819,770 entitled Means for Securing a Motor Vehicle Against Theft and United States Patent 2,964,733 entitled Automobiles or Like Vehicles Fitted with Theft Prevention Devices.
The inventors of Door Locking Means disclose in United States Patent 3,353,383 a combination lock mechanism that must be properly decoded before a latch member can be actu-ated to allow a door to be opened. The system is operated by push buttons and is essentially mechanical in nature, being organized such that if the push buttons are not ~;
operated in the suitable sequence, not only is the latch mechanism not free to move but an alarm is thereby triggered.
As is the case with much of the preceding art, the workable system is relatively complex, heavy and inflexible. Further, such mechanical systems tend to be relatively large, expen- ;~
sive, and limited in their applicability due to such factors z as size, reliability and environmen~al sensitivity.
In United States Patent 3,024,452 entitled Multi-Digit Electrical Door Lock, the inventors disclose a system which is more electrical in nature. A group of push buttons is combined with suitable circuits which respond to a preselected `~
;nput. In the event the buttons are operated in a wrong se-quence, the elec~rical circuitry causes the system to become immobilized and an alarm is initiated. The system is ~urther characterized in that the code to which the system will re- ~ ~;
spond can be changed by mechanical manî.pulation o~ provided selectors. Another concept is disclosed in United States Patent 3~192,448 entitled Keyless Electric Lock wherein a lock bolt is actuated when the available switches are acti-vated in a preselected sequence in order to activate a sole-noid in the system.
While some of the more recent inventions are clear improvements over the preexisting art, the various security s~stems a~aila~le can be characterized as mechanically ori~
ented although some do involve electromechanical or electri-cal activation mechanisms. Nevertheless, such systems are relatively massive, complex and rigid and although their codes may be changed, such changes ordinarily require mechanical manipulation of certain variable components.
The automobile industry in particular currently looks ~or-ward to a consumer oriented security system having good ~`
market acceptance. Such systems should be easily operable, include a capacity to change the access mode quickly and ` ~ ~

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easily, and retain the secureness and reliability of the overall locking system in an inexpensive and rugged embodi-ment of reasonable size and weight.

SUMMARY OF THE INVENTION
A primary obJeet of the present invention is to control access to a vehicle or other enclosure with a mechanism which is operable without a key.
Aceording to the present invention, a Keyless EntryTM
system eomprises a eontrol station ineluding a keyless elec-trical signal generator, logic means for processing suitable eleetrieal signals from the control station, and means re-sponsive to the logic output for eontrolling a mechanism such as a loek. Typieally, a digital electrieal signal is produeed at the manual eontrol station by sequential opera-tion of a plurality of sensitized toueh points. The signal is directed to a logic means which compares the generator signal with a re~erence code and under acceptable conditions ` can be programed to accept a subsequent eonvenience code, and provide an output which is amplified and directed to an electric motor to change the physical position of a re-straint in the entry system. ~ `~
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The manual generation of the eleetrical signals at a sealed control station and the processing of such signals in electronic circuitry are prineipal features of the present invention. Various codes arbitrarily selected b~ an operator having a base code can be programed into the system. The control station is activated with ordinary finger pressure , . ~

34;2 and can be conveniently sized to be packaged to fit an or-dinary door handle found on an automobile. The door latch mechanism is either locked or unlocked in response to a coded sequence of electric pulses which may be either permanent or temporary. The control station has a finger sensitive key-board and often contains piezoelectric switches, a positive contact indicator and a light for illuminating the keyboard.
The invention can be operated with various response functions, ; particularly in automobile applications including activation of the interior lights, unlocking of the hood, and activation ~ ;
of the ignition circuit or an anti-theft alarm.
The present invention is attractive in appearance and is essentially weatherproof when installed in an automobile door. The system provides improved security and can eliminate the need or a key. The keyboard is simple to operate, can be contained within a modest space allotment, permits the use of ten digits and the concomitantly large number of possible combinations of coded signals ~or activation.
In accordance with a specific embodiment of the invention, there is provided an enclosure ha~ring a door con-taining lock means, means for controlling entry to the enc-losure comprises: a control station including means for initiating a sequence of electrical pulses in response to manually applied inputs such pulse initiating means being acc-essible from the enclosure exterior; signal proce~sor means which accepts pulse sequences from the pulse initiating means and contains a base code which is permanently fixed in the processor, the processor being capable of comparing such pulses with the base code and producing a drive signal in response to each set of electrical pulses matched to the base ~ code, the signal processor having means for receiving and , "
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3~2 retaining until programmed otherwise from the pulse initiating means along a convenience code which is received subsequent to and in combination with the base code, the signal `
processor including means for comparing pulse sequences from the control station with the convenience code and for provid-ing a drive signal in response to each pulse sequence which matches either the base code or the convenience code, and means ~or amplifying the drive signal to a p~wer level sufficient to operate the lock.
In accordance with a further embodiment of the invention, there is provided in a vehicle having a door con-taining a power lock, means for controlling the lock which comprises: a control station located at the door exterior and including means for producing pulse electrical signals in response to manual inputs, signal processor means containing ~`
a base code for receiving electrical signals from the control station, for comparing such signalc; with the base code, and for providing a drive signal whenever the input electrical signals from the control station match the base code which is ~0 permanently incorporated into the signal processor means and ; is incapable of modification or elimination b~ signals from the control station, and means for accepting and retaining until programmed otherwise with the control station by a series ;-of electrical pulses delivered to the processor in combin- `
ation with the base code, such series constituting a conven~
ience code which allows the signal processor to respond to ;~
electrical signals produced at the control station and provide a processor output signal each time a series of signals matches either the base code or the convenience code, and means for -amplifying the drive signal to a power level sufficient to drive the power lock.

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In accordance with still yet a further embodiment of the invention, there is provided a control system which comprises: a control station including an entry module which :-is responsive to manual inputs and has a plurality of juxta-posed locations each capable of providiny an electrical sig-nal, particular series of which form signal sequences with each individual electrical signal being identifiable with a particular one of such locations, an electrical signal pro-cessor for providing a processor output signal in response .;
; 10 to any preselected signal sequence from the entry module, the processor including, means for retaining a base code as a first preselected code, and for comparing a signal sequence produced at the entry module with the base code, and for providing a processor output signal each time a signal se-quence matches the base code which is permanently incorporated into the base code retaining means and is incapable of mod-ification or eliminati.on by signals from the entry module, and means for retaining a convenience code as a second preselected code, and for comparing a signal sequence produced at the entry module with the convenience code, and for providing a processor output signal each time a signal sequence matches ~ the convenience code which is incorporated into the convenience :~
; code retaining means from the entry module alone by entering in order the base code followed by a manual input from at least one preselected location at the entry module and finally a series of manual inputs arbitrarily selected by the operator to become the convenience code, amplification means for in-creasing the power of the processor output signal, and means responsive to amplification means for controlling the oper-ability of an apparatus used in combination with the control a system~

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In accordance with still yet a further embodiment of the invention, there is provided an entry system which comprises: a movable member the position of which determines the accessibility to a system or an enclosure, actuation means ~ ;
for changing the position of the movable member, means for controlling the movement of the actuation means; a control station having input means which are responsive to manual inputs including a plurality of discrete locations capable of producing an electric signal characteristic of each location, :
O an electrical signal processor having means for retaining ., .
as a base code a preferred order of such electrical signals and :-for comparing as an input the actual order in which electrical signals are produced by the input means to provide a processor output signal each time an input code matches the base code i~
` which is permanently incorporated into the base code retaining means and is incapable of modification or elimination by sig~
nals from the input means, the electrical signal processor ;
also having means for retaining until programmed otherwise from the control station a sequence of electrical signals con~
stituting a convenience code which allows the signal processor to respond to electrical signals produced ~t the control ' station and provide a processor output signal each time an input code matches either the base or the convenience code amplification means for increasing the power level of the processor output signals; and means responsive to the amplif-ier for moving the means controlling the movement of the actuation means.
The foregoing and other objects, features and advan~
tages of the present invention will become more apparent in ~-3~ the light of the following detailed description of preferred ~-embodiments thereof as shown in the accompanying drawing.

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'~ ' BRIEF DESCRIPTION OF THE DRAWING
Fig. 1 is a block diagram of an overall system in :~
accordance with the present invention~
Fig. 2 is a block diagram with representations for .
some of the more significant interacting components in a system .

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on an automobile;
Fig. 3 is an exploded perspective view of a ~epresenta~
tive lock module used in the system;
Fig. 4 is a simplified schematic of a Keyless Entry system designed for an automobile installation.
Fig. 5 is a functional block diagram of the lock module;
Fig. 6 is a simplified circuit diagram corresponding to ;~
the block diagram of the lock module;
- Fig. 7 is a functional block diagram of the central ~ -processing unit and programable read only memory elements ~
of the module; and - ~ -Fig. 8 is a simplified circuit diagram of the central processing unit~
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DESCRIPTION OF A PREFERRED EMBODIMENT
A sketch of a simplified Keyless Entry system in ac-cordance with the present invention is shown in Fig. 1. The ~ ~
system as disclosed is a device which is suitable for mount- ~ -ing in the door of a conventional automobile and the entire nonmechanical portion of this system is typically packaged in a volume represented by an ordinary bar of soap.
In Fig. 1~ an overall lock system 10 is shown with an electronics grouping 12 comprisîng a control station 14, a signal processor 16 and a signal amplifier 18, and an elec-tromechanical grouping 20 comprising an exterior key station 22, an interior control station 24, a power lock driver 26 a lock 28, an interior door lock button 30, an exterior handle 32 an interior handle 34, linkage 36 and a latch plate 38.
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:re.l~ase- se~ ..Qnce of the loek sys-~em can ~e descr.ibecl ln terms of the ~-loek diagrams shown in ~i.gs. l arld 2. An `, opera~:or produces an input signal. sequellce /-~0 at the control ; .
xtation, I'he signal sequence is proces.sed electronically ,~
and compared with a reference signal in an electr:ic circu1.t ~ :
inc~.l t.l~ing a power supply 42, ~.ll of which .is ~escri~ed ln ~`
more detall herei.nafter. The input sequences which. suitably ~natc~L a coded reerence,sQquence in the proces~solA pass to the ~' si~al ampll,ier ~o provide an elec~ronic~ grou~i.ng output n signal 44. The power level of t:he signal 44 is suf.icient :
to activate t~le pow~r lock driver whi.ch is an element :in t.h~ ;,.
elPc~romec~anîcal ~roupi.ng 2Q an.d is ~"ypicall~ 3 so'lenoid : ;
or a mo~or, A cycle o~ the lcck driver moves the lock per se, el.~J.nlnates a restraint i.n the linkage 34, and either the e~.terior handle 30 or the intelAio:r handle 32 may ~e ma~ipu~
l~te~ callsing the linkage 36 to throw the latch plale 38 thereby releasing the entry member such as a door or trunk 1id. In addition to the door 'lock actuation, th~ s:i.gnal 44 ean ~e used to dr.ive various other ~unctional se~uences i~
2Q so desi.red. Alternatively either the exterior ~ey st,ati,on ?~ locataed on he ~utsi~.de of the door or the inter.ior con^~
trol s~ati.on 24 can control the mechanical group.ing. These two si~es operate ,independent of the grouping 12 and allow ~ne door loc'k to be actuated from inside the enclosure wi~.h a si~.pl.e switch or frnm outside the enclosure with an op- - -~io.rlal ke~ w~.ich is usable in the conventional m~nner as an alternate me.t'tlod of entry.

In an electric circuit which is essentially in parallel with the electronics grouping output signal 44, a relay trigger signal 46 from the grouping 12 triggers a relay 48 connected to the power supply ~to provide various outputs as shown in Fig. 2. For example, a first relay output 50 energizes a keyboard bulb 52 mounted proximate to the control :~
station 14, and a second relay output 54 activates a group of courtesy lights 56 interior of the car.
An exploded perspective view of a preferred Keyless Entry module 58 is shown in Fig. 3. The assembly comprises a touchplate 60, a coverp]ate 62, the keyboard bulb 52, the signal processor and the signal amplifier.
Also shown for the purpose of clarity are the relay 48 and the power supply 42. ~he touchplate comprises a substrate 6~ which is electrically conductive and usually a metal, a layer 66 of piezoelectric material and a plurality of ~
electrodes 68. The application of pressure such as can be ,-applied with the touch of a finger at one of the number locatlons generates a ~oltage between the substrate and the adjacent electrode and results in the touchplate signal 70 ~ -~
which are directed into the signal processor 16. A more -;
extensive discussion of the details of construction and operation for a touchplate of the type described is provided in Canadian Patent Application Ser. No. 288,349, entitled Signal Generator which was filed on Oct. 7, 1977 and is held with the present invention by a common assignee. While the piezo~ectric touchplate has been found to be particularly suited -for the module construction, more ordinary apparatus such as push buttons or toggle switches alone or in combina- ~
tion with a flexible boot are also feasible. ~;
A schematic representation of an entry system as applied to a two-door automobile is shown in Fig. 4. The system îs simplified considerably to show a representative electrical network suitable for supporting two door locks and one trunk lock. Most of the elements shown have been described pre- -viously in the block diagram descriptions although a trunk release switch 72 which is commonly located in the glove box of an automobile is also included. In a typical application the keyboard and courtesy lamps shown are lighted for a period of ten to fifteen seconds after the final entry is -~
made at the control station.
When the present invention is committed to an applica-tion such as access through a door or the trunk in a passen-ger car, the overall operation involves the keyless control of the logic system in combination with a power door lock.
Typically, the fingers of the operator contact the touch- ;
plate and when a sufficient force which is ordinarily in .;
the range of a few ounces to a few pounds is applied thereto, a voltage is generated between the touchplate and an elec-trode. As soon as such a signal is generated from any one or more of the touchplate electrodes, the associated input signal activates the relay 48 and triggers multiple re-sponses. The first output signal 50 from the relay ener-gizes the keyboard bulb 52 so that during periods of limited 3~Z

visibility, the operator can be accurately selective in his manipulations at the touchplate. In addition, ~he relay pro-duces the second output which activates the courtesy lights in the automobile enabling the operator to view the en~ire interior prior to unlocking and entering the vehicle. -The entire grouping 12 namely the control station, the s~gnal processor and the signal ampli~ier is relatively simple and compact. The volume of such a package is typi-cally three to five inches in length and perhaps an inch wide and an inch deep. In addition to being readily enclosed,' ~-the module as described herein ;ncludes no buttons or mechan-ical switches so that the entire package can be made rela~
tively insensitive to the environmental conditions and more speci~ically waterproo~. This feature alone is very desir-able since the difficulty and inconvenience of a frozen key lock is avoided. The dimensions of the module are convenient ~or integrating the package into either the conventional side door locks or trunk lock presently ~ound on automobiles.
The entry system has a permanent signal sequence stored in the signal processor and anytime the correct code is in-troduced at the control station, various prearranged output signals are generated allowing the electromechanical group- ;
ing and the systems responsive to the relay to be operated.
This code may be for the embodiment shown, any ~ive digit number based on the numerals zero through nine. The touch- ;
plate 60 as shown in Fig. 3 has ~ive pads or touchpoints each o~ which is associated with two numerals and a single 3~2 corresponding electrode. The arrangement makes available a greater flexibility in numerical code selection although the number of statistical combinations possible with the `~
five electrode system which is approximately three thousand does not change. Five input locations are considered con-venient to allow a suf~iciently large reserve of possible combinations to accommodate the door locking requirements in an automobile application.
The permanent or base code which will operate the sys- `
tem described is known to a limited number of operators and thereby guarantees limited access to the vehicle without the necessity for carrying a key. ~owever, under some circum~
stances, an operator may wish to provide entry to the auto-mobile ~or a limited duration of time. Under these circum-stances, the operator can provide temporary access to the system by entering the base code followed quickly by touch-ing the one/two digit location and then entering a conve-nience code. The entry of a convenience code is controllable by alternative conditions precedent as well, the more imme-diate of which include the use of the door key at station 22 or entry of a particular program sequence other than a single signal from the one/two digit location. Since the system will respond to either the base code or the convenience code, the operator can provide a person such as a parking ~ `
lot attendant with the temporary access by revealing to him a convenience code. When the operator wishes to revoke such access, he merely enters the base code which erases ~0`3~2 the temporary access code. Similarly the circuitry can be allowed to respond in a manner whereby a base code entry -~
followed by entry o~ the one/two indicator clears the pre-viously stored convenience code. This programable feature of the system can be used repeatedly with the same or dif-ferent convenience access codes being provided at the will " , :, of the operator who is cognizant of the base code. ~ ;;
The essence of a typical signal processor 16 is shown in b]ock diagram ~orm in Fig. 5. The five touchplate signals 70 are entered into a central processing unit (CPU) 74 which -communicates with a programable read only memory (PROM) 76 and together provide a signal which is increased in power in the amplifier 18 and appears ultimately as the output signal 44 which drives the power lock driver 26.
Actual wiring for connecting the integrated circuits with the associated element is shown schematically in Fig. ;~
6. The entry module 58 as shown in detail in Fig. 3, con- ~-tains five distinct number locations, each of which produces an output signal represented as Kl through K5 on the CPU.
The Kl through K5 signals are typically two to three volt sine waves with some noise present. These K signals are ;~
decoded to binary form resulting in signal Ll through L3.
The CPU generates signals Sl through S3 which correspond ;~
to the sequence of K signals. These six output lines then address a programable read only memory (PROM) 76 and generate corresponding outputs 01 through 03 which are entered into CPU which then become the next sequence number Sl through S3. ;

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Therefore for every Kl through K5 input that is in the proper order, a new sequence number is obtained (Sl - S3, 01 - 03).
This process continues until the unlock sequence number is obtained and a signal is generated at LO. If an out of se-quence Kl through K5 is input, the PROM generates sequence 000 at 01 through 03 and the combination must start over.
A grounded network 78 generates a clock frequency for the purpose of synchronizing all the internal signals on the CPU and generating the feedback to the CPU which is present at all times on output LO. Once the correct coded sequence of numbers is introduced at Kl through K5, a signal is gen-erated at output LO which powers two amplifier transistors 80 thereby driving the lock mechanism.
Faults are detected in the transistors 80 with the pre-viously mentioned feedback signa]. which is always present on output LO. As long as the transistors are operating cor- ;~
rectly this feedback is present also at collector 82. The signal is not present in the event either o-f the transistors fail Should this occur, immediately following the next clock signal, a pulse is generated at CBl output which turns on the silicon controlled rectifier 84 and blows a fuse 85 disconnecting the power supply. With this protective cir-cuit, no failure of the transistors 80 is capable of turning on the output and actuating the lock mechanism.
The CPU also generates signals in response to random keyboard inputs, which result in the illumination of the touchplate through amplifying transistors 86 and the light `

3~2 emitting di~de tL~D) shown in Fig. 6. An LED is sometimes incorporated into the system somewhere on the keyboard as ` a positîve feedback indicator. The use o~ an LED in this : manner allows the operator to confirm visually that each input motion is in fact producing the intended input elec-; tric signal. A pair of diodes 88 is provided essentially to regulate the current supply to the integrated circuits and a pair of second diodes 90 protect against overvoltages and reverse polarity o~ the power supply. During long periods of nonuse, the quiescent current draw of the circuit should be minimized and therefore, the programable read only memory has power only during the time that the touchplate is illumi- ~ `
nated which is typically approximately ten seconds.
A functional block diagram of the CPU and the PROM is provided in Fig. 7. The interface area 92, a random access memory and decoder 94, a decoder 96 and an illuminati~n signal generator 98 for the illumination time delay and an unlock signal generator 100 are shown. Provision for a clock to synchronize all of the signals present, means for protecting the integrated circuitry, and a power-on resetter are also shown.
A somewhat detailed schematic of the integrated cir-cuitry of the CPU is described in Fig. 8. A power-on reset circuit 102 protects the circuitry from overvoltages and eliminates spurious signals which occasionally develop and might otherwise activate the power locks. At each input ~' station Kl through K5, a Schmitt trigger 104 is provided ' , to square the input wave and a debounce delay circuit 106 is provided to prevent false inputs due to either a low power or noisy signal. The debounced circuit also prevents the simultaneous actuation o~ more than one key. Rather than to attempt the unwieldly task of handling ~ive individual par-allel input lines, the output from the debounce circuit is processed through a binary encoder 108 and s~ored in a three bit latch 110 for addressing the programable read only memory shown previously. The latch prevents the loss of signal once the key input is removed. A second three bit latch 112 re-ceives outputs 01 through 03 from the programable read only memory and stores such outputs as part of the address for that same programable read only memory. In this manner~ the coded sequence occurs only i~ the correct address is inserted in the programed sequence. An OR gate 114 generates the appropriate ; signals to strobe the latches and trigger an illumination de-lay 116 which is ordinarily ten to fifteen seconds, a period during which the keyboard and courtesy lights are energized.
A~ter a correct permanent code sequence has been ac~
cepted, and ~ND gate 11~ triggers an unlock ~imer 120 which `
simultaneously resets the temporary storage means in the ~
random access memory (RAM) 94. A subsequent signal from Kl ~ -triggers a memory flip-~lop 124 allowing the next five Kl through K5 signals to be read into the random access memory and the memory flip-flop resets. A penalty delay counter 125 and a counter 127 are incorporated to inhibit rapid and continuous sequential operation of all possible codes. Ty-pically after a predetermined number, twenty five for e~ample, . .

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of keystrokes is accomplished with the generation o~ an un-lock signal~ the penalty time delay counter is enabled to inhibit subsequent input signals during the next several seconds or longer. ~;~
A write counter 126 provides a number sequence which becomes half of the address for the random access memory.
The remainder o~ the address comes from the key address out-puts Ll through L3 and the correct sequence is generated by ~he same feedback scheme used in the programable read only memory, namely,for the normal sequencing of the convenience ~;
code, each input must be preceded by a correct input in order to have present the correct address for the input in question.
When the address at the output of the random access memory is correct~ t~le unlock timer 120 is triggered to generate an appropriate unlock signal. A clock circuit 128 comprising inverters, ~eedback resistors and capacitors as is well known, in combination with a monostable multivibrator 130 provides a very short signal pulse which also appears at the lock out-put i there is no unlock signal thereby providing extremely narrow pulses to the output transistors to detect correct operation. The extremely narrow output pulse is fed back `~
at FBl into a two bit shift register 132 so that i~ two suc-cessive signals are not detected at the collector of the last output transistor 80 9 an output CBl will be generated to blow -the fuse 85.
The apparatus and circuitry discussed above are oriented primarily toward automobile entry applications in order to -17~

describe a complete system in an understandable context.
However, the invention has utility over a wide range of applications whic'n include garage and other door operation in commercial and private buildings, access to equipment such as copying or automated credit machines, elevator or automobile ignition operation, and entry to restricted recre-ational facilities.
Although the present invention has been shown and de-scribed with respect to preferred embodiments thereofg those skilled in the art should understand that various changes and omissions in the form and detail thereof may be made therein without departing from the spirit or scope of the t invention.
Having thus described a typical embodiment of our invention, that which we claim as new and desire to secure -: b~ Letters Patent of the United States is:

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Claims (5)

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

1. A control system comprising:
a control station including an entry module which is responsive to manual inputs and has a plurality of juxta-posed locations each capable of providing an electrical sig-nal, particular series of which form signal sequences with each individual electrical signal being identifiable with a particular one of such locations;
an electrical signal processor for providing a processor output signal in response to any preselected signal sequence from the entry module, the processor including, means for retaining a base code as a first pre-selected code, and for comparing a signal sequence produced at the entry module with the base code, and for providing a processor output signal each time a signal sequence matches the base code which is permanently incorporated into the base code retaining means and is incapable of modification or elimination by signals from the entry module, and means for retaining a convenience code as a second preselected code, and for comparing a signal sequence pro-duced at the entry module with the convenience code, and for providing a processor output signal each time a signal se-quence matches the convenience code which is incorporated into the convenience code retaining means from the entry module alone by entering in order the base code followed by a man-ual input from at least one preselected location at the entry module and finally a series of manual inputs arbitrarily selected by the operator to become the convenience code;
amplification means for increasing the power of the processor output signal; and means responsive to amplification means for controlling the operability of an apparatus used in combination with the control system.

2. An entry system comprising:
a movable member the position of which determines the accessibility to a system or an enclosure;
actuation means for changing the position of the movable member;
means for controlling the movement of the actuation means;
a control station having input means which are responsive to manual inputs including a plurality of dis-crete locations capable of producing an electric signal characteristic of each location;
an electrical signal processor having means for retaining as a base code a preferred order of such electrical signals and for comparing as an input the actual order in which electrical signals are produced by the input means to provide a processor output signal each time an input code matches the base code which is permanently incorporated into the base code retaining means and is incapable of modification or elimination by signals from the input means, the electrical signal processor also having means for retaining until programmed otherwise from the control station a sequence of electrical signals constituting a convenience code which allows the signal processor to respond to electrical signals produced at the control station and provide a processor output signal each time an input code matches either the base or the convenience code;

amplification means for increasing the power level of the processor output signals; and means responsive to the amplifier for moving the means controlling the movement of the actuation means.

3. The invention according to claim 2 wherein the input means comprises a keyboard having a smooth uninterrupted surface and each discrete location thereon responds to touch to provide an electrical signal characteristic of each such location.

4. For an enclosure having a door containing lock means, means for controlling entry to the enclosure comprising:
a control station including means for initiating a sequence of electrical pulses in response to manually applied inputs such pulse initiating means being accessible from the enclosure exterior;
signal processor means which accepts pulse sequences from the pulse initiating means and contains a base code which is permanently fixed in the processor, the processor being capable of comparing such pulses with the base code and producing a drive signal in response to each set of electrical pulses matched to the base code, the signal processor having means for receiving and retaining until programmed otherwise from the pulse initiating means along a convenience code which is received subsequent to and in combination with the base code, the signal processor including means for comparing pulse sequences from the control station with the convenience code and for providing a drive signal in response to each pulse sequence which matches either the base code or the con-venience code; and means for amplifying the drive signal to a power level sufficient to operate the lock.

5. In a vehicle having a door containing a power lock, means for controlling the lock comprising:
a control station located at the door exterior and including means for producing pulse electrical signals in response to manual inputs;
signal processor means containing a base code for receiving electrical signals from the control station, for comparing such signals with the base code, and for providing a drive signal whenever the input electrical signals from the control station match the base code which is permanently incorporated into the signal processor means and is incapable of modification or elimination by signals from the control station, and means for accepting and retaining until programmed otherwise with the control station by a series of electrical pulses delivered to the processor in combination with the base code, such series constituting a convenience code which allows the signal processor to respond to electrical signals produced at the control station and provide a processor out-put signal each time a series of signals matches either the base code or the convenience code; and means for amplifying the drive signal to a power level sufficient to drive the power lock.