HEART MONITORING APPARATUS FOR A MOTOR VEHICLE

• US 3,731,672 A
• Filed: 10/04/1971
• Issued: 05/08/1973
• Est. Priority Date: 10/04/1971
• Status: Expired due to Term

• Current Assignee: Duane E. Mcintosh
• Original Assignee: Duane E. Mcintosh
• Inventors: McIntosh, Duane E.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/185,942
• Time in Patent Office: 582 Days
• Field of Search: 128/2.6A,2.6E,2.6F,2.6R,2.1E,DIG.4 340/279
• US Class Current: 600/516
• CPC Class Codes: A61B 5/18 for vehicle drivers or machine operators
• CPC Class Codes: A61B 5/316 Modalities, i.e. specific diagnostic methods
• CPC Class Codes: A61B 5/366 Detecting abnormal QRS complex, e.g. widening

Abstract

The EKG signal of the vehicle operator is sensed through electrodes mounted in the steering wheel and conditioned by amplifying and band pass filtering means to produce a signal which is substantially the QRS complex of the EKG signal. The width of the QRS complex is continually compared with the nominal width for the vehicle operator and an indication of whether the width is narrower or wider is provided to the operator.

Claims

1. Apparatus for monitoring the physiological condition of an occupant of a motor vehicle during vehicle operation comprising;

pickup means for sensing an electrical signal related to the physiological condition of the vehicle occupant, signal conditioning means connected with said pickup means, rectifier means connected with said signal conditioning means for developing an output pulse corresponding to each excursion of the conditioned signal above and below respective upper and lower-voltage levels, pulse generating means for generating a trigger pulse train corresponding to the leading and trailing edge of each output pulse, pulse stretcher means responsive to said trigger pulse train for developing a pulse of duration greater by a fixed time interval than the duration of said trigger pulse train, adjustable pulse stretcher means responsive to the first pulse in said trigger pulse train for developing a pulse of adjustable duration, comparator means responsive to the output of said fixed and adjustable pulse stretchers for developing an error pulse output of duration proportional to the difference in the duration of the output of said fixed and adjustable pulse stretcher means, means including ratiometer means responsive to said error signal for indicating the magnitude and polarity of said error signal, means for manually adjusting the output of said adjustable pulse stretcher to produce a null output from said ratiometer means whereby said ratiometer indicates any significant change in the width of the output signal of said signal conditioning means subsequent to adjustment of said adjustable pulse stretcher, means for counting the number of pulses in said trigger pulse train and for inhibiting the output of said fixed and adjustable pulse stretchers when the number of pulses in said pulse train are less than or greater than a predetermined number.

2. In a motor vehicle provided with a steering wheel, apparatus for monitoring the electrocardiac signal of the operator of the vehicle and for indicating to said operator a change in said signal from the nominal signal of the operator, said apparatus comprising;

a pair of electrodes mounted in said steering wheel for sensing the electrocardiac signal present between the hands of the operator, signal conditioning means comprising first and second amplifiers having their non-inverting inputs connected with respective ones of said electrodes, a capacitor interconnecting the inverting inputs of said first and second amplifiers, a resistance-capacitance network interconnecting the output of each of said first and second amplifiers to their respective inverting inputs, a third amplifier having its respective non-inverting and inverting inputs capacitively coupled to said first and second amplifiers, a third resistance capacitance network interconnecting the output and inverting input of said third amplifier, full-wave rectifier means comprising first and second level detecting means responsive to the output of said signal conditioning means for developing a pulse train containing a pulse for each excursion of the input signal above and below a positive and a negative voltage level, pulse generating means for developing a trigger pulse corresponding to each of the leading and trailing edges of said pulse train, pulse stretcher means comprising a single shot multivibrator triggerable to a semi-stable state in response to a trigger pulse from said pulse generator means and returning to its stable state a fixed interval of time thereafter, a second single shot multivibrator triggerable to its semi-stable state in response to the triggering of said first single shot multivibrator and returning to its stable state after an adjustable time interval, differential power ratiometer means comprising first and second channels, gating and storage means responsive to the state conditions of said first and second monostable multivibrators for developing an error signal for application to one or the other of said first and second channels depending upon which of said monostable multivibrators first returns to its stable state and proportional to the difference in the duration of the unstable state of said first and second monostable multivibrators, means for counting the number of trigger pulses from said pulse generator and for inhibiting said gating means when the number of trigger pulses are less than or greater than a predetermined number.

3. In a motor vehicle provided with a steering wheel, apparatus for monitoring for any change in the electrocardiac signal of the operator of the motor vehicle during vehicle operation comprising first and second electrodes mounted in said steering wheel for sensing the electrocardiac sigNal existing between the hands of the vehicle operator, signal conditioning means comprising amplifying and filtering means connected across said electrodes for developing a scaled version of the QRS complex of said electrocardiac signal, means including full wave rectifying means and pulse generating means for developing a group of trigger pulses over an interval of time related to the width of the QRS complex of said electrocardiac signal, pulse stretcher means responsive to said trigger pulses for developing a pulse of duration greater by a fixed time interval than the duration of said group of trigger pulses, adjustable pulse stretcher means responsive to the first pulse in said group of trigger pulses for developing a pulse of duration corresponding to the nominal width of the QRS complex of the electrocardiac signal of the vehicle operator, comparator means responsive to the output of said fixed and adjustable pulse stretchers for developing a pulse output of duration proportional to the difference in the duration of the QRS complex being monitored and the nominal QRS complex of the vehicle operator, error amplifying means connected with said comparator means, indicator means having first and second input channels and providing an indication of the average magnitude and direction of any deviation of the sensed QRS complex from the nominal QRS complex of the operator, first and second gate means when enabled applying said error signal to said first and second input channels respectively, means for enabling one or the other of said first and second gate means depending upon whether the output of said pulse stretcher means is less than or greater than the output of said adjustable pulse stretcher means, means for counting the number of trigger pulses in each group of trigger pulses for disabling said first and second gate means whenever the number of pulses counted as less than or greater than a predetermined number of pulses.