A FIREARM HAVING AN INTELLIGENT CONTROLLER

Abstract: A firearm having a programmable electronic control (28) for firing electrically ignitable ammunition (17) has a user authorization apparatus (34) and the capability to receive inputs from a plurality of sensors including a magazine presence sensor, a Round-In-Chamber sensor, grip sensors, and a battery status sensor. The electronic control (28) of the present invention has a programmable microcontroller (30), a power supply system using batteries (24), an ignition system that converts low level voltage from the batteries (24) to the required voltage to fire the electrically ignitable ammunition (17), a user authorization apparatus, and an options interface adaptable to receive inputs from system sensors. The firearm of the present invention is programmed to enable firing only if safe and authorized firing conditions are determined. The electronic control (28) can be implemented in either a pistol (1) having an ammunition magazine (23), a multichambered handgun or a revolver.

Description: A FIREARM HAVING AN INTELLIGENT CONTROLLER FIELD OF THE INVENTION This invention pertains generally to firearms and, more specifically to firearms designed to fire ammunition with non-percussion primers. Cross-Reference To Related Applications Some of the material disclosed herein is disclosed and claimed in the following pending U.S. Patent Application entitled "FIRE CONTROL SYSTEM FOR NON-IMPACT FIRED AMMUNITION" (Attorney Docket No. 5001a-243) which is hereby incorporated by reference. BACKGROUND OF THE INVENTION In conventional firearms, either a striker or a hammer and firing pin is provided for detonating percussion primers. Although many advances in conventional firearm design have been made over the years, the underlying principle of ignition by impact is based on technology essentially optimized in the last century. Percussion primers in today's ammunition and the complexity of moving parts in a firearm having a mechanical fire control system are key design constraints in implementing significant improvements in safety, performance and reliability using conventional technology. The complexity of moving parts in a mechanical fire control system is especially problematic in a handgun having multiple chambers, such as a revolver, in which a cylinder is rotatable about its centerline on a center pin, and pivotable on a yoke in order to insert and remove the cartridges. Although electronic components have been designed into the ignition systems of firearms, generally the electrical components either supplement or displace existing parts of the mechanical firing mechanism. The percussion primer is still detonated in the conventional manner, e.g., by impact from a firing pin or striker. U.S. Patent No. 4,793,085 Electronic Firing System for Target Pistol, for example, shows a pistol in which a mechanical trigger bar is displaced by a solenoid. U.S. Patent No. 5,704,153 Firearm Battery and Control Module describes a firearm incorporating a microprocessor in an ignition system for a firearm using conventional percussion primers. Electronic safety mechanisms have been developed for use in revolvers as well as pistols, as illustrated in U.S Patent No. 4,970,819 Firearm Safety System and Method, in which actuation of the firing mechanism is blocked until a grip pattern sensing means on the handgrip of the firearm provides a signal to a microprocessor that corresponds to a prestored grip pattern. Typically, however, the electronic safety system of the '819 patent adds an additional layer of complexity to the revolver, by blocking but not replacing, the conventional mechanical firing mechanism for firing percussion primers. Electronics have also been designed into ignition systems for firearms that use non-conventional primers and cartridges. U.S. Patent No. 3,650,174 for Electronic Ignition System for Firearms describes an electronic control system for firing electrically primed ammunition. The electronic control of the '174 patent, however, is hard-wired and lacks the multiple sensor interfaces or the programmable central processing unit that is found with the present invention. U.S. Patent No. 5,625,972 for a Gun With Electrically Fired Cartridge describes an electrically fired gun in which a heat-sensitive primer is ignited by a voltage induced across a fuse wire extending through the primer. U.S. Patent No. 5,272,828 for Combined Cartridge Magazine and Power Supply for a Firearm shows a laser ignited primer in which an optically transparent plug or window is centered in the case of the cartridge to permit laser ignition of the primer. Power requirements and availability of fused and/or laser ignited primers are problematic however. U.S. Patent No. 5,755,056, for Electronic Firearm and Process for Controlling an Electronic Firearm shows a firearm for firing electrically activated ammunition having a round sensor, and a bolt position sensor. The technology of the '056 patent, however, is limited to a firearm with a bolt action. OBJECTS AND SUMMARY OF THE INVENTION It is one of the objects of the present invention to provide a gun capable of achieving major improvements in performance and safety through the use of an all electronic fire control system that has the capability to interface with a wide variety of safety and fault detection sensors and to integrate the sensor data to verify authorized and safe firing conditions prior to ignition. It is a further object of this invention to provide a gun having a programmable microprocessor used in conjunction with a modular interface design such that the firearm is capable of being readily upgraded as new sensor technology is developed. It is another object of this invention to provide an electronically controlled gun with a simplified modular design for enhanced reliability, maintainability, and competitive cost to manufacture. It is a further object of this invention to provide a firearm with superior performance by eliminating the mechanical forces associated with the mechanical linkages and the impact fired ammunition, which tend to pull the firearm off target. Another object of the present invention is to provide a firearm with an ignition system such that the energy to fire is available in user perceived real time, either by prestoring the energy in a capacitor, or generating the energy to fire after the decision to fire is made. Another object of the present invention is to provide a firearm having an electronic fire control system with all of the aforementioned safety and diagnostic features that can be implemented in either a pistol, a revolver, or a multiple chambered firearm. Still another object of the present invention to is provide a firearm of the foregoing type which is adaptable for use with several types of ammunition, including electrically fired, optically fired and other types of direct energy initiated ammunition. The present invention is directed to a firearm having an intelligent controller for controlling the firing of non-impact primer ammunition from a firearm in which various parameters control the generation and delivery of a firing signal. A firearm, according to the present invention, includes a microcontroller coupled to an onboard power source and a primer ignition probe that delivers an electromagnetic signal to ignite the ammunition primer and cause firing. The controller operates in various modes including a sleep mode and a fire-ready state. The controller may be programmed to run various self- diagnostic tests on components of the firearm as conditional requirements to firing. The controller also may be programmed to determine the presence and operating readiness of a power source, an ammunition round and a magazine prior to firing. The controller may also be programmed to run authorization programs that requires entry of a predetermined code or identification data such as an operator fingerprint. The timing of firing signal generation is controlled by the controller as well. A display screen provides status indications. The controller and other selected components may be housed in a removable module for enhanced security, maintenance, upgrade or replacement. The present invention is further directed to an associated method of operation of a firearm using the control system as described herein. The control system is also adaptable for use with a revolver. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic illustration of a firearm used with ammunition having electrically ignitable primer; Fig. 2 is a schematic illustration of an ignition system having an electronic control; Fig. 3 is an elevational view of a pistol having an electronic fire control system of the present invention; Fig. 4A is a schematic illustration of a fingerprint apparatus provided with the firearm of Fig. 3; Fig 4B is a typical fingerprint pattern read by the fingerprint apparatus of Fig. 4; Fig. 5 is a block diagram of an electronic control system of the present invention; Fig. 6 is a block diagram of a preferred embodiment of a user authorization device adaptable for use with the present invention; Fig. 7 is an elevational view of a mock magazine used as an authorization key, showing a series of selector switches positioned on the bottom surface; Fig. 7A is a schematic illustration of an alternative embodiment of the selector switches of Fig. 7; Fig. 8 is a block diagram of a power supply system of the electronic control system of the present invention; Fig. 9 is a block diagram of an ignition system of the electronic control system of Fig. 5; Fig. 10 is a block diagram of a rear grip sensor utilized with the present firearm; Fig. 11 is a block diagram of an information display system utilized in the firearm of the present invention; Fig. 12 depicts icons used by the information display system of Fig. 11 ; Fig. 13 is a high level block diagram of a control algorithm used with the present firearm; Fig. 14 depicts an algorithm for a cold start routine used in the control algorithm of Fig. 13; Fig. 15 depicts another algorithm used with the control algorithm of Fig. 13, when a positive grip sense interrupt is detected; Fig. 16 depicts a User Authorization algorithm used with the control algorithm of Fig. 13; Fig. 17 depicts a Trigger Initiation algorithm used with the control algorithm of Fig. 13; Fig. 18 depicts a Negative Grip Sense algorithm used with the control algorithm of Fig. 13; Fig. 19 is a schematic view of a multiple chambered handgun having an electronic fire control system; Fig. 20 is a schematic front view of the firearm of Fig. 19 in an 'open' position; Fig. 21 is a schematic rear view of the firearm of Fig. 19 in an 'open' position; Fig. 22 is a schematic view of a revolver having the electronic control system of the present invention; and Fig. 23 is a schematic view of the revolver of Fig. 22 in an 'open' position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Recently developed reliable, chemically conductive, non-impact primers, such as the Conductive Primer Mix developed by Remington Arms Company and described in U.S. Patent No. 5,646,367, are suitable for small arms such as rifles, handguns and shotguns. These non-impact primers have made possible the development of a fully electronic, microprocessor controlled firearm of the present invention. Significant improvement in the reliability and accuracy of powder detonation are achieved by eliminating the requirement for an electromechanical interface between the electronic control and the ammunition. As seen hereinafter, the non-impact primers allow for implementation of a wide range of new safety features, including self-diagnostics, and intelligent sensing of such inputs as biometric authorization, safe firing conditions, and ammunition presence. Referring to Fig. 1 , in a firearm of the present invention, when a trigger 10 is pulled, a transfer bar 12, or equivalent transfer device, activates trigger detection circuitry 11 within an electronic ignition system 15. In the preferred embodiment, the trigger detection circuitry uses two high reliability trigger switches 14,16. The electronic ignition system 15 of the present invention is programmed to deliver an electrical signal 17 to a round of ammunition having a chemically conductive non-impact primer only if safe and authorized firing conditions have been detected. To simulate the feel of a mechanical trigger, a spring resistance is incorporated into the mechanical linkage between the trigger and the trigger switches. In the preferred embodiment, the spring resistance is a force of 3-4 lbs. over approximately 0.150 to 0.200 inches of trigger travel or until the trigger switches are activated. At the transition point, when the trigger switches are activated, the spring resistance preferably increases to approximately 8 lbs. Other combinations of forces and trigger travel distances may be implemented, depending on the requirements of the user. An additional measure of safety is derived from sensing trigger recovery for a predetermined distance in order to preclude unintentional switching. In the preferred embodiment, double throw switches are used to sense both trigger activation and trigger recovery. Other embodiments, such as the use of an extra switch, may be used to sense trigger recovery. As depicted in Fig. 2, the electronic ignition system 19 is comprised of an electronic control system 20 which is the subject of present invention and an ignition probe 22 that forms the interface between the electronic control system and a non-impact electrically ignitable primer 24 of which the chemically conductive primer referenced above is the preferred embodiment. The electronic control system described herein is readily adaptable for use with other types of non-impact direct energy primers. The ignition probe 22 is the subject of the commonly-owned co-pending patent application entitled: "FIRE CONTROL SYSTEM FOR NON-IMPACT FIRED AMMUNITION" referenced above. Referring now to Fig. 3, a first embodiment of the firearm of the present invention is a pistol 1 , more specifically comprising a unitary polymer frame 4, a trigger 10 pivotable about a transverse pin 38 rearwardly to move a trigger bar 12, or other transfer device, which is operably connected to trigger switches 14,16. The frame 4 is adapted to receive a metal slide 6 removably fitted into the frame for slidable reciprocal movement therealong. The slide 6 is secured for such movement by longitudinally spaced pairs of metal rails 8 partially embedded in the polymer of the frame. The rails provide durable metal-to- metal contact and may be used as a system ground for the electronic fire control system. Alternatively, a metal pin embedded in the firearm frame can be used for the same purpose. A chamber 11 is disposed within the breech end of a barrel 13 that is housed in the forward portion of the slide 6 and interfits within a recess provided in the upper portion of the frame 4 to hold the barrel 13 in a given longitudinal position relative to the slide 6. An ignition probe 32 is adapted to move longitudinally within the barrel 13 to make electrical contact with the electrically ignitable ammunition 17 in the chamber 1 1. An information display 19 is disposed at the rearward portion of the frame for displaying critical information to the user such as ready-to-fire, low battery power and diagnostic information. A portion of the frame comprises a handgrip 9 that extends downwardly and rearwardly relative to the axis of the bore or barrel and forward portion of the frame. The handgrip 9 has a pressure sensitive rear grip sensor 18 disposed at the rear portion of the handgrip to detect that the firearm is being handled. A front grip sensor 20 is optional and is located on the front of the handgrip 9. The handgrip 9 has a central cavity or magazine well 21 for receiving a magazine 23 that contains the unfired ammunition. The magazine 23 also contains a primary battery 24 which provides power to the electronic circuitry. Also located within one or more auxiliary cavities 25 within the handgrip and frame is the electronic fire control system 28, having a microcontroller 30, and a user authorization device, preferably an embedded fingerprint authorization apparatus 34. In the preferred embodiment a slot 26 for reading the fingerprint pattern of an authorized user is located in the back- strap area of the handgrip 9. As shown in Fig. 4A, in the firearm of the present invention, a finger 10 or thumb is swept horizontally across the slot 27 in the handgrip of the firearm, and a fingerprint pattern, 29 such as that shown in Fig. 4B, is read by the fingerprint authorization apparatus and compared to prestored patterns. In the preferred embodiment the finger or thumb can be swept either right to left or left to right to allow for ambidextrous use. Fig. 5 is a block diagram of the electronic control system of the present invention. As more fully described below, the electronic control system includes a microcontroller 30, capable of receiving external inputs from a plurality of sensors, an options interface 42 capable of interfacing with at least four additional sensor inputs, a power supply system 36, an information display system 38, and an ignition system 40 which provides the 150Vdc firing pulse 45 to the electrically ignitable ammunition. In the preferred embodiment the microcontroller 30 is operably connected to trigger switches 14, 16, a Round-In-Chamber sensor 52 and a battery status sensor 53. The options interface 42 receives inputs from a rear grip sensor 46, a front grip sensor 48, a magazine/battery (or clip/battery depending on the embodiment) presence sensor 50 and a user authorization device 44. The user authorization device is an important aspect of the present invention. Although the user authorization device may be an embedded fingerprint apparatus, as described herein, other user authorization devices, such as an RF scanner, a combination lock, or an electronic key, can be implemented to perform the same function. Referring still to Fig. 5, the microcontroller 30 is preferably an 8-bit Microchip® PIC16C715, or equivalent, which is normally in a SLEEP, or power saving, mode when the firearm is not in use, and 'wakes up' when an external interrupt from a grip sensor, or other sensing means, detects that the firearm is being handled. The microcontroller, with integrated analog-to-digital (A/D) converters, 2K bytes of program memory (EPROM), 128 bytes of data memory (RAM) and 13 I/O pins, coordinates the timing and execution of all events, and is programmed, as more fully described below, to enable firing only upon verification of authorized firing status. In the preferred embodiment, the options interface 42 is a four channel analog to digital interface integrated into the Microchip® microcontroller. There are numerous alternative devices, however, with quite different memory and I/O configurations that would be equally useful in the present application. As shown in Fig 6., the user authorization device 35 is preferably an embedded fingerprint apparatus comprising a scanning element 36, such as the Thomson-CSF FingerChip™ FC15A140 fingerprint reader, and an Enrollment Database having a Digital Signal Processor (DSP) 38 programmed to compare and match the fingerprint pattern read by the scanning element 36 to previously stored patterns. The DSP 38 transmits a pass/fail signal 39 to the microcontroller through the options interface as depicted in Fig. 5. Scanning, image processing, and verification preferably occurs in user perceived real time (less than 50 msec). Like the microcontroller, the embedded fingerprint apparatus is in a SLEEP mode to conserve power when not in use. Enrollment of an authorized fingerprint requires the use of an authori- zation key. Fig. 7 is a schematic illustration of an authorization key 40. In the preferred embodiment, the authorization key is a mock magazine or clip having a fixed electronic password that is communicated to the central microcontroller through an RF non-contact proximity interface 50 or through a direct connection. In the preferred embodiment, up to five fingerprints can be authorized for one firearm, allowing the user to choose between enrolling several fingers on either hand, or to enroll other authorized users. Positioned on the bottom of the authorization key 40 are a plurality of enrollment selector switches 48 and two LEDs 52,54 to indicate the success or failure of the enrollment attempt. Other embodiments of the enrollment selector switches, using a single LED or buttons or using a Liquid Crystal Display 41 , as shown in Fig. 7A, for example, will occur to those skilled in the art. The electronic control is programmed to identify a valid password and verify that the chamber is unloaded and the firing circuitry disabled during the enrollment process. Referring now to Fig. 8, the power supply system 51 of the present invention is shown schematically. Power to the ignition system 57 for firing the electrically ignitable primer and for all other system requirements is derived from a primary battery 53, and a secondary or standby battery 56. In the preferred embodiment, the primary battery 53 is a 3 volt DC lithium battery disposed at the bottom of the ammunition magazine or clip 23. Because the primary battery 53 is removed with the magazine/clip 23, a secondary standby power source is provided to enable the microcontroller to perform minimal self- test and display functions when the magazine/clip 23 is removed. In the preferred embodiment, the standby battery 56 is a small rechargeable cell which is recharged when the magazine/clip is placed in the firearm. Other power sources having comparable temperature performance range, power density, and shelf life can also be used. A battery presence sensor 55 comprising two pairs of contacts 74 and 76 between the magazine/clip and the firearm frame detects the presence of the battery. A closed circuit in both pairs of contacts 74, 76 indicates that the magazine/ clip has been inserted into the magazine well or central cavity of the firearm. When the magazine/clip is removed, an open circuit between the firearm frame and the magazine/clip at contacts 74 and 76, signifies the absence of the magazine/clip and causes the microcontroller to disable the fire control system according to the logic flow chart depicted in Fig. 17. When the magazine or clip is removed, a round in the chamber cannot be discharged. The signal from the battery presence sensor 55 is transmitted to the micro- controller through the options interface 42 as shown. Those skilled in the art will recognize that several other embodiments of the battery presence sensor are possible. Fig. 9 is a schematic illustration of the Ignition System 40 of the present invention. Using conventional techniques, the ignition system 40 converts the low level dc input from the batteries in the power supply system 39 to a 150 Vdc firing pulse 41 of sufficient duration, preferably one millisecond minimum, to fire the electrically ignitable ammunition. In the preferred embodiment, 150 Vdc is stored across 4.7 μf capacitor that is discharged when the microcontroller 30 transmits a one millisecond fire enable signal to the ignition system. Unlike an ignition system in a bolt action rifle, for example, in the ignition system of the present invention, the capacitor must be able to be recharged and ready to fire again within a minimum of 150-200 milliseconds. In the preferred embodiment, the trigger simultaneously activates two high reliability sealed micro-switches within the electronic control system. The first micro-switch signifies to the microcontroller that a decision to fire has been made. The output of the first micro-switch is debounced using an integrator circuit before it is input to the microcontroller in order to prevent unintentional activation of the fire enable signal. When the microcontroller detects a valid trigger signal from the first micro-switch, a fire enable signal in the form of a one millisecond square wave is transmitted by the microcontroller to the ignition system through the second micro-switch. The width of the square wave transmitted to the ignition circuit corresponds to the duration of the 150 vdc firing pulse applied to the electrically ignitable ammunition. Use of the second micro-switch provides a measure of redundancy to ensure against a false trigger signal resulting from a switch failure or other system malfunction. In the preferred embodiment, ignition is inhibited by the control logic for at least 150 milliseconds between rounds. The 150 millisecond cycle time is designed to ensure that any unintentional trigger activity that may occur due to recoil, hesitation or inertia is ignored by the ignition system. The 150 milli- second cycle time provides a measure of safety without affecting performance since, typically, even an exceptionally skilled user cannot intentionally shoot faster than 200 milliseconds between rounds. Those skilled in the art will recognize that several alternative trigger switching methods may be utilized as well. One such method is to use a Giant Magnetoresistive (GMR) sensor to determine the position of a metal linkage operably connected to the trigger. Such a GMR sensor, used in combination with a single trigger switch, can be implemented to provide a precise and failsafe fire enable signal to the ignition system. Other alternative methods that will occur to those skilled in the art involve the use of piezo-electric or strain gage devices. The ignition system described above is based on ignition by capacitive discharge. Other embodiments of an ignition system capable of delivering firing energy to the electrically ignitable primer in user perceived real time will occur to those skilled in the art. One such alternative is a two stage ignition system, in which the first stage is a pulse width modulated discontinuous dc-to- dc converter and the second stage is a pulse generator capable of generating pulses of sufficient voltage and duration to fire the electrically ignitable ammunition In the preferred embodiment, the ignition system 40 incorporates circuitry to detect the power remaining in the battery. A battery status 43 signal is transmitted from the ignition system 40 to the microcontroller 30 which is programmed to provide a low battery warning to the user sufficiently in advance of the time the battery must be replaced in order to enable the firearm to function for an extended period of time on battery reserves. In the preferred embodiment, the low battery warning is indicated by a message or icon on the information display as shown in Fig. 12. Referring still to Fig. 9, the ignition system also incorporates a Round-In- Chamber sensor 52 for detecting the presence or absence of a chambered round. Detection of a chambered round is accomplished by sensing the impedance of the connection between the ammunition and the firing circuit using a low voltage (below the no-fire threshold) sensing current. To optimize energy transfer and power conservation, the duration of the firing pulse can be adjusted based on the impedance of the chambered round. A signal from the Round-in-Chamber sensor 52 is transmitted to the microcontroller 30 which is programmed, as shown in Fig. 17 below, to read and integrate all sensor data and display the appropriate icon (See Fig. 12) on the information display to inform the user as to the presence or absence of a chambered round. By detecting the impedance of the connection between the ammunition and the firing circuit, the Round-In-Chamber indicator also permits the detection of a present but defective round prior to firing. The Round-In-Chamber sensor 52 can, therefore, warn the user of worn, defective, or contamination build-up within the firearm. The microcontroller 30 is programmed to disable firing in the event a defective round is detected. Fig. 10 depicts the Rear Grip Sensor schematically. An optional Front Grip Sensor can be implemented in the substantially the same manner. As noted above, when the firearm is not in use, the electronic control system is in a suspended SLEEP mode to conserve power. The firearm 'wakes up' when the pressure sensitive Front or Rear Grip sensor 62 detects the firearm is being handled 60 and sends an interrupt to the microcontroller through the options interface 65. In the preferred embodiment, the Rear Grip Sensor 62 comprises a plurality of switches 72 arrayed along the backstrap area of the firearm as shown in Fig. 3. In addition to providing a 'wake up' function, the grip sensor has a dedicated microcontroller 74, preferably a Microchip® PIC 16C71574 or equivalent, programmed to read the pattern of signals from the switches 72 and determine if the firearm is being handled with an ' intent to fire. A firm grip, adequate to keep the firearm under control during discharge, must be sensed by the Grip Sensor in order to fire. Firing is disabled if the firearm is being handled by a child or someone with a very poor or unintentional grip. Referring to Fig. 11 , the information display system of the firearm is depicted schematically. Through the information display, information on a variety of system parameters, including battery status , Round-In-Chamber status, or ready-to-fire status, for example, is presented to the user. The information display system 38 comprises generally an information display 60 and a display driver 58. The information display 60 can be implemented using a combination of a low power, always active, Liquid Crystal Display (LCD) for icons depicting system parameters and a Light Emitting Diode (LED) for a ready-to-fire light. The display driver 58 is programmed to load preset messages to the information display 60 based on control signals received from the microcontroller 30 and is preferably a dedicated microcontroller, such as the Microchip® PIC16C715. Other embodiments of the information display system 38 will occur to those skilled in the art. The information display 38 preferably uses a simple set of internationally understood icons, as depicted in Fig. 12. A padlock 61 indicates the system will not fire because an unauthorized user is handling the firearm. A flashing padlock indicates the firearm is awaiting authorization. A bullet icon, which can be displayed alone 63 or with a line through it 65, signifies whether a live round is in the chamber. A bullet icon with a red LED indicates that a live round is in the chamber and the firearm is authorized and capable of firing. A battery icon 67 is used to signify low battery power. A triangle with an exclamation point 69, or alternatively, all icons flashing, symbolizes a system malfunction has been detected. Referring to Fig. 13, a high level block diagram of the control logic 70 of the present invention is depicted. As shown, the firearm is normally in either a SLEEP mode 71 or a STANDBY mode 73 unless the. firearm is undergoing a cold start 74 which occurs when the firearm is used for the first time or the batteries are replaced. A cold start algorithm is depicted in Fig. 14 below. Referring still to Fig. 13, the transition from SLEEP mode to STANDBY mode occurs when a grip sense interrupt is detected by the microcontroller, which event causes the firearm to go through a "Positive Grip Sense Wake-Up" algorithm (Block 72 and Fig. 15). The firearm will transition to the STANDBY mode only if a "User Authorization" algorithm (Block 77 and Fig. 16) is successfully completed. Once in STANDBY mode 73, the firearm will fire when a "Trigger Firing Event" (Block 75 and Fig. 17) occurs. If the firearm is in STANDBY mode and the microcontroller detects a "Negative Grip Sense Event" (Block 76 and Fig. 18), the firearm will return to SLEEP mode 71 as shown. Referring to Fig. 14, the algorithm for a cold start or battery replacement routine is shown. The cold start algorithm 80 is followed if the firearm has never been used or the battery is replaced. As shown, the control logic first performs an internal self-test 81. If a fault is detected an error indicator will be displayed 82 and the firearm will enter SLEEP mode 83. If the internal self-test is successful, all icons on the information display will be displayed for approximately three-seconds 84, the Round-In-Chamber and the battery status will be updated 85, 86, the firearm status will be set to UNAUTHORIZED 97 and the firearm will enter SLEEP mode 88. As programmed, firing is disabled during the cold start algorithm. Referring to Fig. 15, when a positive grip sense interrupt 90 is detected, the electronic fire control system will first perform an internal self-test 91. If the self-test routine is detects a system fault a system malfunction symbol will be displayed 92 and the firearm will revert to SLEEP mode. If the self-test is successful, all icons will be displayed for approximately three-seconds 94 and the padlock symbol on the information display will flash 95 as the User Authorization algorithm 96 depicted in Fig. 16 is performed. If the User Authorization algorithm cannot be successfully performed for any reason, the firearm status will be set to UNAUTHORIZED 97 and the firearm will revert to SLEEP mode 98. If the user is authorized, as determined by the User Authorization algorithm 96, the control will interrogate and update the Round- In-Chamber status, battery status, and magazine status 99. If the firearm is ready to fire 100, the ready-to-fire indicator on the information display will be illuminated 102 and the firearm will enter STANDBY mode 104. In the event that an error is detected, the display will be updated accordingly 101 and the firearm will revert to SLEEP mode 103. The firearm is programmed not to discharge unless the user has been properly enrolled and authorized according to the algorithm depicted in Fig. 16. Referring to Fig. 16, the algorithm to Interrogate User Authorization 110 is depicted schematically. As indicated, the control first determines, by the presence or absence of the enrollment key 112, whether the intent of the user is to enroll an authorized user or to authorize a previously enrolled user. If the enrollment authorization key is present , a PIN access code associated with the authorization key is verified 132, the fingerprint scanner is activated 134 for a predetermined time, preferably ten-seconds 136, during which time the fingerprint of the user is scanned. From the raw scanned data, the fingerprint image is reconstructed and processed 138 and stored 148 in memory. The algorithm is then reset 149 to the beginning 110. If the enrollment key is present 112, the user may verify a previously enrolled fingerprint using the same method. When the fingerprint image has been reconstructed (Block 138) and formatted (Block 139), it is compared with a previously enrolled fingerprint 140 for verification 142 and the algorithm is then reset 146 to the beginning 110. If the fingerprint image does not match, an error message will be displayed 144 on the information display and the algorithm reset as shown 146. Referring still to Fig. 16, if the enrollment key is not present 112, the firearm is programmed to authorize use only if the user's fingerprint matches a previously stored fingerprint pattern. As shown, the fingerprint scanner is activated 114 for a predetermined period of time, preferably 10 seconds, during which time the fingerprint of the user is scanned 116. The raw scanned data is then reconstructed 118 and processed 120 and compared with previously stored patterns 122. If there is a match, the lock status is set to AUTHORIZED 124 and the firearm returns 126 to the main control program (Fig. 13) and enters STANDBY mode. If there is no match, the lock status is set to UNAUTHORIZED 128, disabling the firearm, as the firearm returns 130 to the main control program (Fig. 13). Fig. 17 is a schematic illustration of the Trigger Initiation algorithm 150. As shown, when the firearm is in STANDBY mode, ready to fire, and the trigger is pulled, the electronic control polls a series of internal and external parameters including the grip sensors 151 , the user authorization signal 152, the magazine presence sensor 153, the round in chamber indicator 154, and the energy available to fire 155. If any system parameters are not in the proper state, the electronic control is programmed to update the information display 156 with the appropriate error message and abort firing 157. If all system parameters indicate the firearm is authorized and ready to fire, a fire enable signal 160 is transmitted to the ignition system to discharge the electrically ignitable ammunition. Referring to Fig. 18, when the firearm is in STANDBY mode, and the grip sensors detect that the firearm is no longer being handled, the firearm will revert to SLEEP mode as indicated. If a negative grip sense interrupt is received from the grip sensors 170 while the firearm is in STANDBY mode, the electronic control will monitor the input of the grip sensors for a positive grip 172 for a predetermined time, preferably ten-seconds 174, and if a positive grip is not detected, the electronic control will set the lock status to UNAUTHORIZED 176, initiate a grip sensor self-test routine 177 and revert to SLEEP mode 180. In the event that a positive grip sense is detected within the predetermined time, the firearm will return to STANDBY mode, ready to fire. In a second embodiment, the electronic fire control system, described above, is implemented in a multiple chambered gun depicted in Figs. 19-21. Referring to Fig. 19, the multiple chambered handgun 160 comprises generally a frame 161 which includes a handle portion 163, having a rear grip sensor 164 and optionally a front grip sensor 165. The handle 163 has a central cavity 168 for receiving a clip 162 that houses the primary battery 166 which provides the primary power to the electronic circuitry. Referring to Fig. 20, the multi-chambered handgun 160 has a barrel 167 adapted to receive several cartridges within a plurality of longitudinal bores 169. A plurality of ignition probes 171 , in axial alignment with the longitudinal bores 169, are positioned to fire the cartridges in a predetermined sequence. Referring to Fig. 21 , the barrel 167 is hinged to the frame through a hinge assembly 173 and is pivotable about a hinge pin 175. When the firearm is 'open', as shown, the empty brass or cartridge cases may be removed, and the firearm reloaded. The barrel 167 may then be swung back into the 'closed', or firing position, and locked with locking mechanism 177. An information display 179 is disposed above the handle as shown. As in the first embodiment, the preferred user authorization means is an embedded fingerprint apparatus 180 located, as shown, in the backstrap area of the handle. In yet another embodiment, the electronic fire control system described above is implemented in a revolver. The revolver embodiment of the present invention is shown generally at Fig. 22. The revolver 200 comprises generally a frame 202 which includes a handle portion 204, having a rear grip sensor 206 and optionally a front grip sensor 208. The handle 204 has a central cavity 210 for receiving a clip 212 which contains a primary battery 214. The revolver 200 has a rectangular opening or window 220 adapted to receive a cylinder 222. An information display 226 is disposed above the handle as shown. As in the other embodiments, a slot 228 for reading the fingerprint of the authorized user is disposed in the backstrap area of the firearm. As shown in Fig. 23, the cylinder includes a plurality of longitudinal bores 216 which are adapted to position, in sequence, cartridges (not shown) to the firing position in axial alignment with the barrel 218 and an ignition probe 219. The cylinder 222 is rotatable about its centerline on a center pin 223. The cylinder 222 is also pivotable on a yoke 224. When the cylinder is 'open', the empty brass or cartridge cases may be removed and the cylinder reloaded. It may then be swung back into the window 220, ready for firing upon determination of safe and authorized firing conditions. While the present invention has been illustrated and described with respect to a particular embodiment thereof, it should be appreciated by those of ordinary skill in the art, that various modifications to this invention may be made without departing from the spirit and scope of the present invention.

Claims: We claim: 1. A firearm for firing a round of ammunition having a non-impact primer, said firearm comprising: a power source for generating an electromagnetic firing signal ; sensing means for generating a control signal indicative of the value of a firing control parameter; a programmable controller that receives said control signal and determines an operational mode of said firearm such that said firing signal is caused to be delivered only if said firearm is in a firing mode; and an ignition probe that delivers said firing signal to said non-impact primer effecting detonation thereof, thereby causing the round of ammunition to fire. 2. A firearm according to claim 1 , wherein said round of ammunition has a casing having a rear surface formed in part by a primer element; and at all times when said round of ammunition is positioned in a firing chamber of said firearm, said ignition probe is in physical contact with said primer element. 3. A firearm according to claim 1 , further comprising trigger means for indicating to said controller when an operator selectively initiates a firing signal. 4. A firearm according to claim 3, wherein activation of said trigger means is a firing control parameter. 5. A firearm according to claim 2, further comprising round detecting means for detecting and indicating to said controller when an ammunition round is positioned in said firing chamber, wherein the presence of an ammunition round in said firing chamber is a firing control parameter. l o 6. A firearm according to claim 5, wherein said round detecting means comprise means for detecting an electrical current flowing through a circuit in which a chambered ammunition round is a conductor. 7. A firearm according to claim 1 , further comprising energy level measuring means for measuring and indicating to said controller the amount of energy stored in said power source. 8. A firearm according to claim 7, wherein a predetermined amount of energy stored in said power source is a firing control parameter. 9. A firearm according to claim 1 , further comprising sensing means on a grip of said firearm for detecting and communicating to said controller when an operator engages said grip. 10. A firearm according to claim 1 , further comprising magazine sensing means on a grip of said firearm for detecting and communicating to said controller when a magazine is inserted into said grip in a predetermined position. 11. A firearm according to claim 10, wherein predetermined positioning of a magazine into said hand grip is a firing control parameter. 12. A firearm according to claim 10, wherein said magazine sensing means include battery detection and measuring sensing means for detecting and indicating to said controller the presence and level of a battery in said magazine. 13. A firearm according to claim 1 , further comprising user authorization means for programming the identity of operators authorized to fire said firearm. 14. A firearm according to claim 13, wherein indication of an authorized operator is a firing control parameter. 15. A firearm according to claim 1 , further comprising key means whereby physical implementation of said key means with said firearm is a firing control parameter. 16. A firearm according to claim 13, wherein said user authorization means include a fingerprint scanner for scanning an image of an operator's fingerprint and generating corresponding signals thereof, and signal processing means for processing said signals and comparing the same to authorization signals corresponding to prestored authorized operator fingerprint signals. 17. A firearm according to claim 16, further comprising a fingerprint authorization key adapted to be selectively inserted into said firearm and to receive input of fingerprint images to be converted to and stored as authorized operator fingerprint signals. 18. A firearm according to claim 16, further comprising remote fingerprint authorization means adapted to receive input of fingerprint images remotely from said firearm, whereby said images are subsequently converted to and stored as authorized operator fingerprint signals in said firearm. 19. A firearm according to claim 1 , further comprising coded authorization means for entry of coded data whereby correspondence of said coded data to a prestored set of data is a firing control parameter. 20. A firearm according to claim 1 , wherein said energy signal is an optical energy signal. 21. A firearm according to claim 1 , wherein said energy signal is a thermal energy signal. 22. A firearm according to claim 1 , wherein said energy signal is an electrical energy signal. 23. A firearm according to claim 1 , further comprising information display means for displaying the value of a firing control parameter. 24. A firearm according to claim 1 , wherein said controller is programmed to operate in a sleep mode until a predetermined control signal is delivered from one of said sensing means. 25. A firearm according to claim 9, wherein said predetermined control signal is a signal indicating that the body of said firearm has been engaged by an operator. 26. A firearm according to claim 1 , wherein said controller is contained in a selectively removable module adapted to be inserted into and removed from the body of said firearm. 27. A firearm according to claim 1 , wherein said power source is contained in a selectively removable module adapted to be inserted into and removed from the body of said firearm. 28. A firearm according to claim 13, wherein said user authorization means are contained in a selectively removable module adapted to be inserted into and removed from the body of said firearm. 29. A firearm according to claim 15, wherein said key means are adapted to be inserted into and removed from the body of said firearm. 30. A firearm according to claim 1 , further comprising ignition control means for controlling the delivery of said firing signal from said power source to said ignition probe. 31. A firearm according to claim 30, wherein said ignition control means control the timing of the delivery of said firing signal from said power source to said ignition probe. 32. A firearm according to claim 30, wherein said ignition control means increase the magnitude of said firing signal from said power source to said ignition probe. 33. The firearm according to claim 30, wherein said ignition control means comprise a capacitor for storing said firing signal delivered from said power source and deferring delivery of said firing signal to said ignition probe until a predetermined signal is received by said capacitor from said controller. 34. The firearm according to claim 31 , wherein said ignition control means prevent the generation of successive firing signals less than 100 milliseconds apart. 35. The firearm according to claim 30, wherein said ignition control means comprise a pulse width modulated discontinuous dc-to-dc converter and a pulse generator adapted to generate pulses of voltage sufficient to fire said non-impact primer ammunition. 36. A method of operation of a firearm having a controller for firing nonimpact primer ammunition, said method comprising the steps of delivering to said controller an initiation signal indicating a preliminary fire-ready state; initiating an electromagnetic-magnetic firing signal from a power source in response to a signal from said controller; and delivering said electromagnetic firing signal from a non-impact ignition primer to said non-impact primer ammunition to cause firing of a round of said ammunition. 37. The method according to claim 36, further corhprising the steps of: performing a self-diagnostic test to determine the integrity of various components of said firearm prior to delivery of said firing signal to said primer, whereby firing of said firearm is disabled if the results of said test do not meet predetermined requirements. 38. The method according to claim 36, further comprising the steps of: delivering user authorization data signals to said controller indicative of authority to initiate delivery of said firing signal; and comparing said user authorization data signals to prestored data signals. 39. The method according to claim 36, further comprising the steps of: determining whether or not sensors on a grip of said firearm are activated. 40. The method according to claim 36, further comprising the steps of: determining whether or not an ammunition magazine is properly inserted into a corresponding magazine well of said firearm. 41. The method according to claim 37, further comprising determining whether or not an ammunition round is properly chambered in said firearm. 42. The method according to claim 37, wherein said self-diagnostic test further comprises the steps of examining said power source to ensure sufficient stored power to execute firing of said ammunition round. 43. A method of operation of a firearm control system in a firearm, said method comprising the steps of: initiating a cold start signal, thereby beginning a preliminary sequence of procedures; performing a self-diagnostic test to determine the integrity of various firearm components; displaying the status of said firearm components in response to said self-diagnostic test; and establishing a sleep mode in which said firearm control system is inactive until an interrupt signal is received. 44. The method according to claim 43, further comprising the steps of: detecting an ammunition round in a firing chamber of said firearm and displaying a corresponding signal; detecting the presence of a power source of said firearm having a predetermined amount of energy and displaying a corresponding signal; detecting the presence of an operator's grip on said firearm; determining authorization status of said operator; enabling firing capability of said firearm in response to a determination of positive authorization status, or disabling firing capability firearm in response to a determination of negative authorization status whereby said sleep mode is established. 45. A method of operation of a firearm control system in a firearm that fires ammunition having a non-impact primer, said method comprising the steps of: establishing a sleep mode in which said firearm control system is inactive until an interrupt signal is received.; detecting the presence of an operator's grip on said firearm; performing an authorization routine to determine whether or not said operator is an authorized operator; establishing a standby mode in which said firearm is ready for firing; establishing a firing mode constituting the only mode in which a firing signal can be caused to be delivered to said non-impact primer; and initiating a firing signal in response to a trigger signal. 46. A method of operation of a firearm control system in a firearm, said method comprising the steps of: establishing a sleep mode in which said firearm control system is inactive until an interrupt signal is received; detecting the presence of an operator's grip on said firearm; performing a self-diagnostic test to determine the integrity of various firearm components and displaying the status of said firearm in response to said self-diagnostic test; determining authorization status of said operator, whereby said firearm remains disabled if said status operator is determined to be unauthorized; determining the presence of an ammunition round in a firing chamber of said firearm; determining the amount of stored energy is a battery source in said firearm; and signaling that said firearm is in a firing mode. 47. A method of operation of a firearm control system in a firearm, said method comprising establishing a sleep mode in which said firearm control system is inactive until an interrupt signal is received.; detecting the presence of an operator's grip on said firearm; and determining whether or not a key is presently configured with the firearm. 48. A method according to claim 47, further comprising initiating operation of a fingerprint scanner; receiving an image of an operator's fingerprint, and generating an input signal indicative of said fingerprint; comparing said input signal to a prestored signal corresponding to an authorized operator; and determining whether or not said input signal corresponds to an authorized operator. 49. A method according to claim 48, further comprising receiving an access code signal for determining whether or not further operation of the firearm is authorized. 50. A method of operation of a firearm control system in a firearm, said method comprising the steps of receiving a trigger signal; determining whether or not said firearm is properly gripped by an operator; determining whether or not said operator is an authorized operator; determining whether or not an ammunition magazine is properly inserted into said firearm; determining whether or not an ammunition round is properly positioned in a firing chamber of said firearm; determining whether or not said firearm has sufficient energy stored to fire said ammunition round; and determining whether or not to enable firing, whereby if said firing is aborted a corresponding signal is displayed or said firing is enabled. ZΌ 51. A firearm according to claim 3, wherein said trigger means includes a Giant Magnetoresistive (GMR) device. 52. A firearm according to claim 9, wherein said sensing means recognizes an intent to fire grip of the operator constituting engagement of both a forward and a rearward sensor . 53. A firearm according to claim 16, wherein a slot through which said fingerprint scanner scans the operator's fingerprint is located in a rearward surface area of the firearm distal to a firearm muzzle. 54. A firearm according to claim 30, wherein said firing signal is delivered within 250 milliseconds of a preceding firing signal. 55. A firearm according to claim 15, wherein said key means is encoded to enable only that particular firearm. 56. A firearm according to claim 15, wherein said key means further comprises a supplemental key means configured with a remotely mounted authorization unit. 57. A firearm according to claim 6, wherein said round detecting means further comprises means for comparing the magnitude of electrical current passing through said round with a preselected value and generating a defective round signal should the measured magnitude be different than a preselected value of said round current.

Inventors: KLEBES JOHN F, KLEBES, JOHN, F.
Applicants: SMITH & WESSON CORP, SMITH & WESSON CORP.
Application year: 1999
Main classification: F41A
IPC codes: F41A17, F41A19