SU858770A1 - Digital pulse frequency meter - Google Patents

Description

The invention relates to medical technology, in particular to a diagnostic cardiac device, and can be used in automatic systems for continuous patient monitoring and in sports medicine. A digital pulse frequency meter is known that includes a sensor, an amplifier driver, two oscillators, a switch, a linearly varying voltage generator, a pulse counter, a digital indicator, a reset driver, and a reference voltage source l. However, the use of a known digital voltage stabilization meter leads to an increase in energy consumption, which limits the duration of the meter with an autonomous power source. The purpose of the invention is to reduce power consumption from an independent power source by eliminating voltage stabilization. The goal is achieved by the fact that in a digital pulse frequency meter containing a sensor, the output of which is connected to the amplifier amplifier input, the output of which is connected to the input of the first single vibrator and the input of the reset generator, the output of the first single vibrator is connected to the input of the second single vibrator and the input of the key, the output the second one-shot is connected to the input of the generator of a linearly varying voltage, the key output is connected to the first input of the pulse counter, the second input of which is connected to the output of the driver with dew and output to the input of a digital indicator-connected counter administered generator scan type and a voltage divider whose output is connected to the first input of the generator scan type, the second input of which is connected to the output of the generator linearly varying voltage whose output is connected to the input key. FIG. 1 shows a structural diagram of a digital pulse rate meter; in fig. 2 - time diagrams of the meter. Digital pulse frequency meter contains sensor 1, amplifier-shaper 2, shaper 3 reset, one-shot 4 and 5, alternating voltage generator b, alternator

7 of the scanning type, key 8, voltage divider 9, pulse counter 10 and digital indicator 11.

The output of the sensor 1 is connected to the input of the amplifier-former 2, the output of which is connected to the inputs of the first one-shot 4 and the former 3. The output of the first one-shot is connected to the inputs of the second one-shot 5 and the key 8. The second one-shot 5, the generator of linearly varying voltage, the generator 7 of the scanning type, the key 8, the counter

10 pulses and digital display

11 are a series circuit. The output of the voltage divider 9 is connected to the first input of a sweep-type generator 7.

Digital pulse rate meter works as follows.

The signals from the pulse sensor 1 (plot 1 in Fig. 2) are fed to the amplifier driver 2. The signal from the amplifier of the driver (plot 2 in Fig. 2) is sent to the reset driver 3, which sets the pulse counter 10 to the zero state, and to the one-shot 4 A single-shot 4 triggers a single-shot 5. A single-shot 5 forms a short pulse (plot 5 in Fig. 2), the front of which the generator of linearly varying voltage (clay) is reset, and the generator starts. The linearly varying voltage of the generator 6 (plot b in Fig. 2) is fed to one of the inputs of a sweep-type generator 7, to the other input of which is fed a reference voltage from the divider 9

At the output of a sweep-type generator (GDT), an impulsive sequence is obtained, the frequency of which is inversely proportional to the linearly varying voltage of the CLAY (plot 7 in Fig. 2). The output pulses from the GDT arrive at key 8, which opens for a time equal to the duration of the pulse of the one-shot 4 (plot 8 in Fig. 2).

The pulse counter 10, therefore, in each pulse period will count the pulses coming from the output of the GDT B for the duration of the output pulse of the one-shot 4. After the pulse drops, the counter stops and the digital indicator 11 stores the number corresponding to the instantaneous pulsation frequency to the end of the next ripple period.

The number of pulses on the counter after the end of the counting is determined by the expression

,)

t ir-r jJup

 - oRj I,

where t

scale factor kent;

pulse duration

OVD one-shot 4;.

and. - reference voltage

divider 9;

(T, is the frequency generator of the turning-type ragrt; - voltage is GLINE;. - pulsation frequency.

g

nVAbC In this pulse frequency meter, the reference voltage is a part of the power supply voltage of GLINE and GDT, which ensures the invariance of the instrument reading with respect to the voltage of the self-contained power source. This also reduces the additional error in the measurement of gastrointestinal pulsus, due to the short-term instability of the autonomous power source, which is a consequence of external and internal destabilizing factors (pickup, switching interference, etc.).

The invariance of the proposed pulsomer with respect to the supply voltage eliminates the need to use a parametric stabilizer as a reference voltage, which increases the service life of an autonomous power source and makes the pulse meter particularly promising when used in a small-sized transfer of medical equipment.

Claims (1)

1. USSR author's certificate 464304, cl. A 61 B 5/02, 1974. "-I -i 7 I