A DRIVE AND CONTROL SYSTEM FOR POWER GENERATION AND PULSE GENERATION IN AN ELECTRONIC LOCK

Abstract: A drive and control system for the generator and a separate switch or electrical pulse data input of an electronic lock. The drive system includes a direct drive from the dial knob (10) to the dial cam (40), which carries thereon a segmented ring magnet (42) or a device that is capable of actuating an electrical, mechanical, or optical switch. The ring magnet or other switch actuating device rotates with the dial cam and dial knob. The drive system also includes a clutch in the drive chain between the direct drive and a generator/stepper motor (34). The clutch permits the dial to generate power when rotated in a first direction. The switches effectively provide electrical pulses which may be used as a data input. It is desirable to electrically disconnect or disable the switch from sending data representative pulses to the logic circuits or microprocessor (62) of the electronic controls when power is generated. This is accomplished by monitoring a signal that indicates the generator is generating electrical energy and only permitting the passage of emitter pulses to the electronic controls when the generator power output does not exist. Thus, this drive and control system for the generator and the emitter or electrical pulse data input of an electronic lock permits power to be generated as the dial is rotated in a first direction and pulses representative of the approximate dial position to be provided to the electronic controls as the dial is rotated in a second opposite direction.

Description: A DRIVE AND CONTROL SYSTEM FOR POWER GENERATION AND PULSE GENERATION IN AN ELECTRONIC LOCK FIELD OF THE INVENTION This invention relates to self-powered electronic locks and, more specifically to the drive and control system for the generator and a separate switch or electrical pulse data input of such an electronic lock. BACKGROUND OF THE INVENTION Electronic combination locks may be powered from a number of electrical energy sources, such as batteries, utility power sources, or self-contained generators. Where the power for the lock operations is derived from manually operated self contained generator, it is desirable to also enter and /or control the data input from the same knob which may be rotated to cause power generation to power the lock. Because the rotation of the dial knob is resisted by the resistance of the rotation of and electro-motive forces on the rotor of a generator of the stepper motor/generator that generates power, the human factors can be improved by only having to drive the generator when power generation is required as opposed to at all times that the knob is rotated. This provides an opportunity to disconnect the drive to the generator in one direction to lighten the load on the knob permitting a more accurate control of the knob during data input. Miller et al, United States patent 5,061,923, discloses a stepper motor driven bi- directionally to generate power and accomplish data entry in both rotational directions. The stepper motor or generator disclosed the '923 patent generates alternating positive and negative voltage pulses that have a sinusoidal wave form. The sinusoidal signal provided by the stepper motor/generator must be shaped in additional electronic circuitry prior to being sent to the micro processor. This circuitry converts the sinusoidal signal provided by the stepper motor/generator from a sine wave into a square wave. Jasper, United States patent 5,493,882, discloses the driving of the generator by the manual movement by a variety of elements, such as a dial ring, key, lever, or push- pull member while controlling data entry by rotary manipulation of the dial knob. The application of Thomas R. Clark, et al, Serial No. 08/985,308 filed December 5, 1997 (Docket No. MH 96-005) entitled "Emitter And Power Drive System For An Electronic Lock" discloses a drive system incorporating a drive for a generator and drive for an emitter stepper motor. The drive incorporates two uni-directional spring clutches, each to be only drivingly operational in opposite directions. Reliability considerations and costs dictate the reduction of the number of mechanical parts to the greatest extent possible consistent with the functional requirements for the lock. These reliability requirements focus the design effort on the elimination of parts subject to wear. OBJECTS OF THE INVENTION It is an object of the invention to provide reliable and accurate data entry to the lock electronic controls, as well as reliable power generation to operate the lock. It is another object of the invention to improve the human factors of an electronic lock by reducing the loading on the manually operated dial during at least selected portions of the operation of the lock. It is a further object of the invention to electronically control the input of combination data to permit such combination data input only when the dial is rotated in a pre-designated direction. SUMMARY OF THE INVENTION A mechanical drive is provided between the dial knob and the generator/stepper motor of a self-powered electronic combination lock. The drive includes a unidirectional spring clutch or other one-way drive clutch to drive the stepper motor/generator when the knob is rotated in a first direction and effectively disconnect the manual drive input through the dial knob to the generator when the dial knob is rotated in a second, opposite direction. This disconnection of the generator from the dial- knob in the second rotational direction reduces the loading on the dial knob when rotated in the second direction for data input. The drive system also includes a direct drive from the dial knob to the dial cam, which carries thereon a segmented ring magnet or a device that is capable of actuating an electrical, mechanical, or optical switch. The ring magnet or other switch actuating device rotates with the dial cam and dial knob. A ring magnet presents alternating polarity magnetic fields to a pair of Giant Magneto Resistive (GMR) devices. Typical GMRs usable in this device are designated AD001 available from Non- Volatile Electronics, Inc., Eden Prairie, Minnesota. The GMRs are devices which act as magnetically actuated solid state switches or switch-like devices. The GMRs effectively provide electrical pulses which may be used as a data input. However, unlike Miller et al, it is undesirable to have emitter pulses provided to the electronic controls at all times that the dial is being rotated. Accordingly, it is desirable to electrically disconnect or disable the pulse source, the GMR, form sending data representative pulses to the logic circuits or microprocessor of the electronic controls. This is accomplished by monitoring a signal that indicates the generator is generating electrical energy and only permitting the passage of emitter pulses to the electronic controls when the generator power output does not exist. A better understanding of the invention may be had form viewing the attached drawings and an understanding of the detailed description of the preferred embodiment of the invention. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings incorporated in and forming part of the specification illustrate several aspects of the present invention. In the drawings: Figure 1 is an illustration of the drive train between the dial knob spindle and the stepper motor/generator of the electronic lock. Figure 2 is a partial sectional view of the stepper motor/generator drive train for the electronic lock. Figure 3 is a rear view of part of the lock with the lock cover removed to reveal the magnet ring and GMRs used for generating electrical pulses for data entry. Figure 4 is a block diagram of a portion of the electronic controls and the generator that controls the creation of an emitter pulse input to the CPU of the lock only during that period where the lock is operating and the generator is not generating power. Reference will now be made in detail to the present preferred embodiment of the invention, examples of which are illustrated in the accompanying drawings. A DETAILED DESCRIPTION OF THE BEST MODE OF THE PREFERRED EMBODIMENT OF THE INVENTION Referring initially to Figures 1 and 2, the drive for the generator is shown where dial knob 10 is drivingly connected to gear 12. Gear 12 in turn rotates gear 14. Gear 14 is part of a compound gear formed of gears 14 and 16 and thus gear 16 rotates with gear 14. The rotation of gear 16, meshed with gear 18 causes gear 18 to rotate in the same direction of dial knob 10 and gear 12. Gear 18 is either drivingly connected to or a part of compound element which includes arbor 26. Arbor 26 is coaxially disposed and rotationally mounted on stepper motor shaft 28. An arbor 30 is pressed into stepper motor shaft 28 and is of the same external diameter as arbor 26. Circumscribing arbors 26 and 30 is a coil spring 32 of a spring clutch 38 which, when revolved about the axis of stepper motor shaft 28 in one direction, will tend to wrap tightly onto the arbors 26 and 30 and thereby transmit the torque of gear 18 to arbor 30 and stepper motor shaft 28 rotating stepper motor shaft 28 in turn causing stepper motor 34 to generate electrical power. If gear 18 is rotated in the opposite direction by rotation of the dial knob 10 in the opposite direction from that described above, the arbor 26 will tend to unwind the coil spring of the spring clutch 38 causing the spring to slip on either or both arbors 26, 30 disconnecting the drive to stepping motor 34 preventing electrical generation as a result of the dial knob rotation in the opposite direction referred to above. Referring now to Figure 3, rotation of dial knob 10 in turn rotates spindle 20 without regard to the direction of the rotation of dial knob 10. Attached to spindle 20 for rotation therewith is a dial cam 40 which carries thereon a generally ring shaped magnet 42. Thus, dial knob 10 is drivingly connected to magnet 42. Magnet 42 has plurality of alternating polarity magnetic elements 44 of generally equal arc length and a single segment 46 of substantially greater arc length. As each segment is passed over a Giant Magneto Resistive (GMR) device, such as GMRs 50, 52, the magnetic field causes the GMR to switch from a conductive to a non-conductive state or vice versa. This switching action causes an electrical potential impressed on GMR 50 and/or 52 to be intermittently conducted through the GMR 50 and/or 52. This intermittent electric potential forms a train of electrical pulses. Thus, the output voltage of GMR 50 and/or 52 can vary between a first voltage and a second voltage. The pulses may then be used by the electronic controls to acquire data. Acquisition of data such as the combination from such a pulse train is well known in electronic locks. Alternatively, any other device that can trigger a sensor that can act like a switch may be used in place of the magnet 42. The triggering device must be selected to actuate the particular sensor selected. Examples of these sensors, include, but are not limited to, photoelectric circuits, reed switches, micro-switches, opto-isolaters, optical diodes, optical encoders, hall effect devices, or similar switch type devices. These sensors could then be used in place of GMRs 50 and 52. The output from the sensor(s) are then fed to the microprocessor 62 (Figure 4). Referring now to Figure 4, in order to accommodate the desire to generate pulses for use by the electronic controls in only one direction of dial knob rotation, one phase of the generator typically is connected through the power supply and signaling circuitry 60 to the GMR circuitry 64. GMR 52 is typically the GMR that senses magnetic field transitions for data entry and may be the only GMR active under the control of the CPU 62 during this phase of operation. The generator phase output is provided to the GMR circuitry 64 and a corresponding generator signal GEN is then provided to the CPU 62 by the GMR circuitry 64 indicating that the generator is generating power. The CPU functions to turn off or eliminate a GMRON signal that would otherwise activate GMR 52. When GMR 52 is activated by the GMRON signal, GMR 52 provides signals from the GMR circuitry 64 signals to the CPU 62 for use by the CPU 62. When the generator is not generating electrical power, i.e. the lock is idle or the dial knob is rotating in the direction opposite to that used to generate power, typically a clockwise direction, the GMR circuitry 64 does not receive any voltage form the designated phase of the stepper motor, indicating the non-generation of power and does not function to pass the GEN signal to the CPU 62. The CPU 62, having not received the GEN signal, operates to provide the GMRON signal to the GMR circuitry and accordingly, the GMR and its circuitry 64 emits pulse signals in response to rotation of the magnet ring past GMR 52 in the direction opposite that experienced when this generator is generating power. Thereby, the GMR 52 is not enabled when the generator is generating power and the lock is adequately powered for electrical operation. GMR 50 may be operated in a similar manner. By enabling GMR 52 selectively, the CPU 62 is not required to process the pulse input or consume electrical power to do so at a time when the generator is generating power to store the power necessary to operate the lock. The second GMR 50 is provided to permit detection of the wide magnetic section 46 in cooperation with GMR 52 for purposes of actuating the lock at an appropriate time relative to the dial cam 40 and under predefined conditions to open the lock and effect lock bolt withdrawal. It should be understood by one skilled in the art that the particular signals may be logically reversed and that the exemplary directions of rotation may be reversed if so desired, and such changes should not be interpreted to remove the resulting apparatus from the scope of protection provided hereby.

Claims: CLAIMS We claim: 1. A generator drive and control system for an electronic lock, said system comprising: a dial; a generator; and a clutch, said clutch rotationally connecting said generator to said dial when said dial is rotated in a first direction, said clutch rotationally disconnecting said generator from said dial when said dial is rotated in a second opposite direction, whereby said generator does not generate power when said dial is rotated in said second direction. 2. The generator drive and control system of claim 1, wherein said clutch is a unidirectional spring clutch. 3. The generator drive and control system of claim 2, wherein said generator is an electric motor. 4. The generator drive and control system of claim 3, wherein said electric motor is a permanent magnet stepper motor. 5. An electrical pulse generation and control system for an electronic lock, said system comprising: a dial; and a means for switching an electrical signal between a first voltage and a second voltage, said switching means triggered by rotation of said dial. 6. The electrical pulse generation and control system of claim 5 further comprising: a means for electrically disconnecting said switching means from a microprocessor. 7. The electrical pulse generation and control system of claim 5 further comprising: a means for disconnecting said switching means, whereby the output from said switching means is not utilized by a microprocessor. 8. The electrical pulse generation and control system of claim 5 further comprising: a means for disabling said switching means, whereby the output from said switching means is not utilized by a microprocessor. 9. The electrical pulse generation and control system of claim 5 wherein said switching means comprises: a segmented magnet, said magnet joined to said dial, said segmented magnet comprising a plurality of alternating polarity magnetic elements; and at least one GMR, said GMR located within the magnetic field of said segmented magnet, whereby the changing magnetic field caused said dial rotating said segmented magnet causes said GMR to change state and act as a switch. 10. A generator drive, electrical pulse generation and control system for an electronic lock, said system comprising: a dial; a generator; a clutch, said clutch rotationally connecting said generator to said dial when said dial is rotated in a first direction, said clutch rotationally disconnecting said generator from said dial when said dial is rotated in a second opposite direction; and a means for switching an electrical signal between a first voltage and a second voltage, said switching me-ans triggered by rotation of said dial, whereby said generator does not generate power when said dial is rotated in said second direction. 11. The generator drive, electrical pulse generation and control system of claim 10 further comprising a means for electrically disconnecting an output from said switching means from a microprocessor when said generator is generating power. 12. The generator drive, electrical pulse generation and control system of claim 10 further comprising a means for disconnecting an output from said switching means from a microprocessor when said generator is generating power. 13. The generator drive, electrical pulse generation and control system of claim 10 further comprising a means for disabling said switching means when said generator is generating power. 14. The generator drive, electrical pulse generation and control system of claim 10 wherein said switching means comprises: a segmented magnet, said magnet drivingly connected to said dial, said segmented magnet comprising a plurality of alternating polarity magnetic elements; and at least one GMR, said GMR located within the magnetic field of said segmented magnet, whereby the changing magnetic field caused said dial rotating said segmented magnet causes said GMR to change state and act as a switch. 15. The generator drive, electrical pulse generation and control system of claim 14 further comprising a means for disabling said switching means when said generator is generating power. 16. The generator drive, electrical pulse generation and control system of claim 15 wherein said disabling means disables said GMR. 17. The generator drive, electrical pulse generation and control system of claim 15 wherein said disabling means removes power from said GMR. 18. The generator drive, electrical pulse generation and control system of claim 10 wherein said switching means comprises: a segmented magnet, said magnet drivingly connected to said dial, said segmented magnet comprising a plurality of alternating polarity magnetic elements; and at least one Hall effect device, said Hall effect device located within the magnetic field of said segmented magnet, whereby the changing magnetic field caused said dial rotating said segmented magnet causes said Hall effect device to change state and act as a switch. 19. The generator drive, electrical pulse generation and control system of claim 18 further comprising a means for disabling said switching means when said generator is generating power. 20. The generator drive, electrical pulse generation and control system of claim 19 wherein said disabling means disables said Hall effect device. 21. The generator drive, electrical pulse generation and control system of claim 19 wherein said disabling means removes power from said Hall effect device.

Inventors: DAWSON GERALD LEE, KELLY MICHAEL JACKSON, DAWSON, GERALD, LEE, KELLY, MICHAEL, JACKSON
Applicants: DAWSON GERALD LEE, KELLY MICHAEL JACKSON, MAS HAMILTON GROUP INC, DAWSON, GERALD, LEE, KELLY, MICHAEL, JACKSON, MAS-HAMILTON GROUP, INC.
Application year: 1998
Main classification: E05B49
IPC codes: E05B47, G07C9