| 摘要 |
A method and a device for measuring the pulse beat frequency on the basis of the formation of the mean value of the time intervals between a number of consecutive pulse beats. According to the invention measurement of a sequence of four consecutive pulse intervals between the pulse beats is carried out, the second time being compared with the first, the third with the second and the fourth with the third. If in no case the difference DELTA T between a time and the preceding one exceeds a certain absolute amount, for instance +/-10%, the mean value of the four times is formed, is inverted and is indicated with a factor 60 as the number of pulse beats per minute. If, on the contrary, a time is found to deviate from the preceding one with more than DELTA T, for instance owing to a passed-over or an extra pulse beat, the measuring and comparing cycle is restarted until each time interval of the sequence is maintained within the permitted limits, after which the mean value is formed and indication takes place as in the former case. A device for carrying out the method can consist of a sensor (S) applied in the region of an artery, which sensor is connected to a signal processor (SB) in the form of a semicustom-chip for amplification, filtration and detection for emitting spike pulses to a pulse beat frequency calculating unit (PFB) in the form of a microprocessor programmed to perform the above-mentioned comparison repetition of the measuring cycle, if any, formation of mean value and inversion, and factor output of the result to an LCD-indicator (I). The whole pulse frequency meter can be made in a wristwatch model. |
