JPS62161345A - Constant speed exhaust apparatus for automatic hemomanometer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention measures blood pressure by pumping gas into the cuff to close the artery, then switching to the exhaust state and exhausting the gas pumped into the cuff. This invention relates to a constant-speed evacuation device for an automatic blood pressure monitor that lowers cuff pressure at a preset constant rate upon exit.

(Prior art) Conventionally, when using the so-called Itiva Rocci method, in which the systolic and diastolic blood pressures are measured by generally wrapping a cuff around the upper arm, pumping air, and detecting the overlapping Korotkoff sounds generated from the arteries, the arterial After air is pumped into the cuff until it is occluded, the cuff pressure is gradually evacuated at a rate of 2 to 3Hnf1g/sec.The Korotkoff sound that occurs as the cuff pressure decreases can be detected using a microphone installed in the cuff. The cuff pressure at which the first Korotkoff sound occurs is set as the highest surface pressure value, and the cuff pressure at which the last Korotkoff sound that occurred during the process of continuous evacuation disappears. An automatic blood pressure measuring device has been used that measures the blood pressure as a diastolic blood pressure value and displays each measured value on a display device, for example, an LED display.

A normal exhaust valve is generally used as a means to gradually exhaust the cuff pressure at a speed of 2 to 3 tm 11 (1/sec), and a predetermined driving current is applied to the cuff valve to maintain the exhaust valve at a constant opening. A method of opening was adopted.

(Problems to be Solved by the Invention) According to the conventional evacuation means, since the opening degree of the evacuation valve is constant, the evacuation speed is usually fast when the cuff pressure is high, and as the cuff pressure becomes low, the evacuation speed is As a result, it was difficult to decrease the cuff pressure linearly over time. There is a close relationship between the falling state of cuff pressure and the systolic and diastolic blood pressure values measured during the cuff pressure falling process, and if the pumping speed is too fast, the systolic blood pressure value will be low.
The diastolic blood pressure value will be measured too high, and conversely, if the pumping speed is too slow, biological reactions such as urinary blood will occur in the blood pressure measurement artery, which will not only make the blood pressure measurement inaccurate but also cause damage to the surface pressure fenestration itself. This results in problems.

Therefore, when measuring blood pressure, it is an important requirement to lower the cuff pressure in a linear manner, and the accuracy of the blood pressure measurement value is extremely unstable when measuring blood pressure using the conventional evacuation means, which has no linearity in the rate of fall of the cuff pressure. There was a problem that the measured values were not necessarily accurate.

Therefore, in the present invention, in order to reduce the cuff pressure linearly at a preset speed, the cam that drives the valve of the exhaust section is shaped so that the cuff pressure falls linearly, and the cam is The problems of conventional evacuation means are solved by providing a constant speed evacuation device that controls the rotational speed of a rotating motor in accordance with the cuff pressure drop speed.

(Means for solving the problem) The technical means for solving the above problem is to pump gas into a cuff wrapped around the upper arm or the like to IP the artery! After the tti, the automatic blood pressure measuring device that measures the systolic and diastolic blood pressures automatically switches to the exhaust state and exhausts the gas pumped into the cuff. The cuff is equipped with a pressure chamber section formed to allow the cuff to fall, and an exhaust valve for discharging the gas in the cuff at a predetermined speed through the pressure chamber section and lowering the cuff pressure at a preset cuff pressure drop rate. an exhaust section; a cam that engages with the exhaust valve to drive the exhaust valve; a motor that rotates the cam in accordance with the set cuff pressure lowering speed; The constant speed exhaust device is configured to include a drive control section that outputs a corresponding drive signal, and a setting section that outputs a setting signal corresponding to the set cuff pressure drop rate to the drive control section.

(Function) The evacuation speed at which the gas from the cuff is evacuated using the setting section;
However, when the rate of fall of the cuff pressure is set and gas is pumped into the cuff to create a w1 chain in the artery, the pressure in the pressure chamber becomes equal to the cuff pressure.

When the automatic blood pressure measuring device is automatically switched to the exhaust state in this state, a drive signal corresponding to the set cuff pressure lowering speed is outputted from the drive control section to the motor. The motor rotates the cam, which in turn drives the exhaust valve of the exhaust section, and controls the exhaust valve to an opening degree corresponding to the set cuff pressure drop rate. Therefore, in the constant speed exhaust device, the gas from the cuff is exhausted to the atmosphere at a predetermined exhaust speed through the pressure section and the exhaust section through the pressure section and the exhaust section, so that the cuff pressure decreases linearly. It has the effect of causing The systolic blood pressure value and the diastolic blood pressure value are measured in the process of linearly decreasing the cuff pressure.

(Example) Next, an example of the present invention will be described in detail with reference to the drawings.

Figure 1 shows an example of an automatic blood pressure measuring device that has a built-in constant-speed exhaust device that exhausts the gas (e.g., air) pumped into the cuff at a predetermined exhaust speed and lowers the cuff pressure at a preset rate. It is a front panel fixture installation diagram of an Example.

For example, the front panel 2 of the automatic blood pressure measuring device 1 includes Aol.
Illuminated push button type power switch 3 for turning on 00V commercial power
is attached and the power switch 3 is turned on, the required power is supplied to the electric circuit shown in FIG. 2, which will be described later. When measuring the systolic blood pressure, diastolic blood pressure, and pulse rate of the subject, a measurement number setting switch 4 is used to select how many times to measure the same subject and whether or not to display the average value of the measured values as a story. is installed and set to the OFF position, one measurement is taken, and if it is set to the 2 position, two measurements are taken.
If the position is set to 3, measure 3 times, and display each measured value or the measured average value on the LED display 7, 8, 9, and printer 36 that can display graphics, which will be described later. Is displayed. The printer 36 may be provided separately from the main body of the automatic blood pressure measuring device 1, or may be built-in. In addition, as shown in the overall system diagram of FIG. 3, a cuff 32 is wrapped around the upper arm 31 and the artery 3
The microphone 34 detects blood vessel sounds generated from the blood pressure measuring device 1, and the pressure pump 41 in the automatic blood pressure measuring device 1 is in a state where gas can be pumped into the cuff 32 through the tube 35. At this point, a Starmie switch 5 is installed, which is turned on when automatic surface pressure measurement is started. When the star 1-switch 5 is turned on, the inside of the cuff 32 and the constant speed exhaust device 51 (described later)
Gas is fed under pressure, and predetermined pressure measurements are then automatically carried out. Note that a reset switch 6 is provided which is turned ON when it is necessary to clear the previous measurement data and display data, such as when measuring the blood pressure of another subject or the same subject again.

In addition, the maximum blood ff value displayed on the LED display 7, LE
D If you do not want the patient to see the diastolic blood pressure value displayed on the display 8 and the pulse rate displayed on the LED display 9, select O.
A blind switch 10 is provided to prevent the LED indicators 7, 8 and 9 from displaying. When the blind switch 10 is turned on, each of the measured values becomes LE.
Since it is not displayed on the D displays 7, 8, 9, it is possible to prevent psychological agitation when measuring the blood pressure or pulse rate of the subject. The upper limit pressure setting switch 11 is for setting the maximum pressure value of the gas pumped into the cuff 32 as described above, and the set value is, for example, 120ttytH (
J, 150mIH (J, 1801NRH+If, 21
It can be set to 0 whale HIJ 1240 ml 1 g.

As an operation switch related to the printer 36 for printing out each measurement data of the subject, when the printer 36 prints out the measurement data, it is used to determine whether to display it in a digital state or in an analog state, that is, in a graphic state. A display mode changeover switch 12 for selecting a display mode, a copy switch 13 for causing the printer 36 to print a copy, and a paper feed switch 14 for causing the printer 36 to feed paper are provided.

In addition, the level meter 15 that displays the level of the Korotkoff sound generated from the artery 33 when measuring the blood pressure of the subject can detect abnormal conditions when the timing of the pulse rate generated from the artery 33 is irregular, that is, when an arrhythmia occurs. An irregular indicator light 16 to display, an error indicator light 17 to display an error when some kind of measurement error occurs during blood pressure measurement, and furthermore, the above-mentioned systolic blood pressure value, diastolic blood pressure value, pulse rate, and occurrence of arrhythmia are required. (a) [Sometimes a speaker SP is provided to notify the user by voice. Note that the sound output from the speaker SP is cut off when the blind switch 10 is turned on. The cuff pressure lowering speed setting switch 18 is used to set the speed at which the cuff pressure is lowered when the gas pumped into the cuff 32 is exhausted.For example, the cuff pressure lowering speed is set to 2.4 or 6.8.
．． The cuff pressure drop rate can be set to an arbitrary value such as 10 mHg/sec.In addition to unit time, the cuff pressure drop rate can be set to any value such as pulse-to-pulse or heart rate.
It is also possible to use biological information such as te.

Next, FIG. 2 shows a block diagram of the performance controller 1211 of this embodiment, in which a microcomputer CPU, such as a manufacturer's model Z-80, is used as the center of the control function of the microcomputer CPU. The following I! 1 path is connected. That is, a real-time clock circuit 20 for supplying a clock signal required by the microcomputer CPU, and an A/D converter circuit 21, that is, an electric signal generated when the microphone 34 detects a vascular tube generated from the artery 33. A pressure sensor 23 is installed which converts the output signal of the amplification circuit 22 into a digital signal, detects the pressure inside the cuff 32, converts it into an electrical signal, and outputs it. A pressure sensor amplification circuit 24 is provided to amplify the electrical signal output from the pressure sensor amplification circuit 24, and the analog signal corresponding to the cuff pressure outputted from the pressure sensor amplification circuit 24 is converted into a digital signal and output.
The Δ/D converter circuit 21 which operates DC0808) is connected. Further, a storage circuit 25 includes a programmable read-only memory P-ROM for storing a measurement program, predetermined data, etc. necessary for blood pressure measurement.
and a storage circuit 26 including a random access memory RAM for temporarily storing measurement calculation data and the like.

Further, the microcomputer CPU is equipped with an output interface 27 using, for example, manufacturer model 82791C, which is operated according to the address command and output command of the microcomputer CPU, and the output interface 27 uses the manufacturer's model 82791C.
It is connected to the L-E D display 7 for display, the LED display 8 for displaying diastolic blood pressure, and the LED display 9 for displaying pulse il'J, and overrides the display signal output from the microcomputer CPU. . The microcomputer CPU also stores the systolic blood pressure value, diastolic blood pressure value,
A voice synthesis circuit AME is connected to notify the pulse rate and the occurrence of arrhythmia by voice. This voice synthesis circuit AME uses, for example, a ROM memory, outputs a digital signal corresponding to the voice from the ROM memory according to the address specification of the microcombicoater CP LJ, and converts the digital signal into an analog signal using a D/A converter circuit DAC. The circuit is configured such that the analog signal is converted into a signal, amplified by the next amplifier circuit AMP, and then energized to the speaker SP to output the audio from the speaker SP.

Further, the printer 36 and the microcomputer CPU
For example, manufacturer model 825 for signal communication with
An input/output interface 28 equipped with 5 ICs is connected to the microcomputer CPU, and two printer interfaces for serially transmitting printer signals are provided between the input/output interface 28 and the printer 36.

The microcomputer CPU further includes another input/output interface 30 equipped with an 82551C of the same type as described above.
are connected to the input/output interface 30, and the input/output interface 30 controls the measurement count setting switch 4, start switch 5, reset switch 6, blind switch 10,
Upper limit pressure setting switch 11, display format changeover switch 12
, the signals output from the copy switch 13 and the cuff pressure lowering speed setting switch 18 are received and transmitted to the microcomputer CPU, and the display signals output from the microcomputer CPU are received and the irregular indicator lights 16 and It is relayed to the error indicator light 17.

The doujin output interface 30 also includes the cuff 3.
A pressurizing pump drive circuit 42 is connected to drive a pressurizing pump 41 that pumps gas into the cuff 2, and a rapid pump driving circuit 42 is connected to the cuff 32 to rapidly exhaust the gas pumped by the pressurizing pump 41 from inside the cuff 32. A stepping motor drive that drives a rapid exhaust valve drive circuit 44 that drives the exhaust valve 43 and a stepping motor 45 (described later) that forms a constant speed exhaust device that exhausts the pressurized gas from within the cuff 32 at a predetermined exhaust speed. The circuit 46 is connected.

Note that the programmable read-only memory P-ROM of the storage circuit 25 stores the pulse rate of the subject and the respective lowering speeds 2, 4, 6, 8, 10 all ( ]/Sec, a program table for determining the frequency of the drive signal for the stepping motor 45 is stored.

FIG. 3 shows the entire system of this embodiment as described above, in which a cuff 32 is wrapped around the upper arm 31 of the subject, and gas is pumped into the cuff 32 from the pressurizing pump 41 to blood the artery 33. The measurement is started by detecting blood vessel sounds generated from the artery 33 with the microphone 34 while the flow is stopped, and various measurement data including the systolic blood pressure value and the diastolic blood pressure value are typed out at the end of the predetermined measurement. This shows a state in which the printer 36 is connected to the automatic blood pressure measuring device 1.

Next, gas is pumped into the cuff wrapped around the upper arm, etc. to close the artery, and then switched to the exhaust state and the gas pumped into the cuff is pumped into the cuff.
The configuration of the constant-speed exhaust device 51 for performing constant-speed exhaust at a cuff pressure-lowering speed preset by the cuff pressure-lowering speed setting switch 18 will be described with reference to FIGS. 4 and 5.

As shown in the figure, the gas pumped from the pressure pump 41 is 4
The pressure chamber 52 is connected to the pressure chamber 52 through the pipe 53 so as to be able to be pumped to the pressure chamber 52 of the constant speed exhaust device 51 through the hollow type manifold 48.
It is connected to the inlet 54 of.

As shown in FIG. 5, the gas introduced from the inlet port 54 passes through a tube 55 made of a flexible and airtight material, accumulates pressure in an inner cylinder 56 made of aluminum, for example, and is discharged inside the inner cylinder 56. Gradually increase the atmospheric pressure.

One end of the duplex 55 is airtightly attached to the inner step X section of the lower lid 57 to which the inlet 54 is attached, while the other end is attached to the lower end of the inner tube 56 in a closed manner. The tube 55 is folded back to the outside of the inner tube 56 over the entire length of the inner tube 56 with its both ends airtightly attached as described above.
An outer cylinder 58 is fitted on the outside of the outer cylinder 5, and the lower lid 57 is fitted and fixed to the lower end of the outer cylinder 58.

A first spring 59 whose one end is attached to the lower lid 57 is inserted into the inner cylinder 56, and the other end of the spring 59 is in contact with the inner diameter surface of the inner cylinder 56 at the axial center. It is attached to the center of a disk-shaped movable plate 60 that is attached in a semi-fixed state to. The movable plate 60 is provided with a plurality of holes 60H for allowing gas to flow therethrough.
A horizontal central axis 608 is formed in the center of the end surface opposite to the end surface to which one end of the spring 59 is attached, and the center axis 608 is concentric @60S.
A small diameter hole 60C is bored through the axial center of the shaft. A proximal shaft 618B of a needle valve 61 having a conical valve 61v formed in its intermediate portion is slidably inserted into the small diameter hole 60C.

Further, one end of a second spring 62 is attached to the center @60S, while the other end of the second spring 62 is elastically attached to the base end of the valve 61V via a washer 63. When the tip of the facing valve 61V comes into close contact with the small diameter exhaust hole 64H formed in the center of the exhaust cover 64 and communicating with the atmosphere due to the repulsive force of the spring 62 of No. 2, the inner cylinder 56
to prevent the release of pressurized gas into the atmosphere. Also,
The tip side shirts I to 61ST of the needle valve 61 are always in a state of protruding outside the exhaust hole 64H. Note that the exhaust lid 64 is fixed to the inner diameter portion of the upper end of the inner cylinder 56.

As the gas pressure-fed from the pressure pump 41 is accumulated in the pressure chamber 52, the tube 55 expands, and the inner WI5
Push 6 upwards. At this time, the inner cylinder 56 is pushed up to a position where the air pressure in the pressure chamber 52 and the tensile force of the first spring 59 are balanced, and the tip position of the tip side shaft 61ST of the needle valve 61 also moves up by the same distance. .

On the other hand, the cam 65 is attached to the power shaft of the stepping motor 45, and when the stepping motor drive circuit 46 applies a drive current to the stepping motor 45 and the motor 45 rotates, the cam 65 is attached to the tip of the needle valve 61. It rotates in contact with the shaft 61ST, causing the two-dollar valve 61 to move linearly. When the cam 65 linearly moves the needle valve 61 against the repulsive force of the second spring 62, that is, the shaft 61ST is moved by the cam 65 to move the needle valve 61 linearly.
4, the valve 61V gradually increases the exhaust area of the exhaust hole 64H, and in order to exhaust the gas in the cuff at a predetermined rate, the cuff pressure decreases at a constant rate.

Note that in order to integrally assemble the outer cylinder 58 and the stepping motor 45, a mounting bracket 66 made of, for example, an aluminum angle and plate is used. The bracket 66 is also used as a fixing aid for fixing the constant speed exhaust device 51 at a predetermined position within the automatic blood pressure measuring device 1.

Next, the operation of this embodiment will be explained according to the flowchart shown in FIGS. 6(1) to 6(3).

The cuff 32 is placed on the upper arm 31 of the subject, the power plug of the automatic blood pressure measuring device 1 is inserted into a commercial power outlet, and the power switch 3 is turned on. Initialize the state of each circuit. Next, as a preparation operation for blood pressure measurement, the number of measurements is set using the measurement number setting switch 4, the upper limit cuff pressure of the cuff 32 is set using the upper limit pressure setting switch 11, and the blood pressure measurement value and arrhythmia are set using the blind switch 10. Set whether or not to display the occurrence of arrhythmia on the ED display 7.8.9 and the irregular indicator light 16, or set whether or not to display the above measurement value or the occurrence of arrhythmia by voice, and Pressure lowering speed setting switch 1
8 to set the cuff pressure drop rate. After the above preparation operations are completed, by turning on the start switch 5, the microcomputer CPU reads the setting 1 shift and the setting state signal. Next, the microcomputer CP
U reverses the stepping motor 45 to release the contact between the cam 65 and the needle valve 61, closes the constant speed exhaust device 51 and the rapid exhaust valve 43, and then drives the pressurizing pump 41. When gas is pumped from the pressure pump 41 into the cuff 32 via the pipe 35 and into the pressure chamber 52 via the pipe 53, the pressure sensor 23 sequentially detects the cuff pressure and An analog signal corresponding to the cuff pressure is output to the D converter circuit 21. The A/D converter circuit 21 converts an analog signal corresponding to the cuff pressure into a digital signal and outputs it to the microcomputer CPU. The microcomputer CPU inputs a digital signal corresponding to the cuff pressure, converts it into a display signal, and causes the LED display 7 to sequentially display the cuff pressure value.

Next, the microcomputer CPU determines whether or not the cuff pressure of the cuff 32 is increasing normally.
It is determined whether or not the value l+(l has been reached. If the value has not been reached, the error indicator light 17 is turned on and the rapid exhaust valve 43 is opened to cause rapid exhaustion. Furthermore, the printer 36 prints an error message. On the other hand, within 5 seconds from the start of pressurization on the cuff 32, 10
If it is determined that the distance has reached 0 m 9, the pressurizing pump 41 is stopped. Next, depending on whether the blind switch 10 is set to ON or OFF in the preparation operation, the LED display devices 7, 8, 9 will display the systolic blood pressure value, diastolic blood pressure value, and pulse rate. After determining whether to notify the measured value and the occurrence of arrhythmia by voice or not, the microcomputer CPU sends a message to the microphone 34 → amplifier circuit 22 → A/D converter without operating the constant speed exhaust device 51 for 2 seconds. circuit 21
The system recognizes the patient's blood vessel sounds that are input through the system and determines whether the blood vessel sounds contain Korotkoff sounds. Thereafter, the flowchart 11- continues from 1A in FIG. 6 to 2A in FIG.

In 2 of Fig. 6, in order to avoid the influence of extraneous noise, etc., even if the microcomputer CPU determines that the Korotkoff sound is combined with the blood vessel sound, the microcomputer CPU ignores the Korotkoff sound for one second, and then makes a decision. If it is determined in step STA that the Korotkoff sound has occurred, it is determined that the subject's artery 33 is not occluded,
In order to pressurize the cuff 32 again, the rapid exhaust valve 43 is once opened for rapid exhaustion. The microcomputer CPU is
It is determined whether the cuff pressure of the cuff 32 has become, for example, 10 mm 11 g, and when it is determined that it has decreased to 10 s*H (l), the upper limit pressure is set to 210 mm 11 g with the bending upper limit pressure setting switch 11 in the preparation operation. In this case, a value obtained by adding roughly 30ml and 11g is set in the RAM of the memory circuit 26 as the upper limit pressure.

Furthermore, a new upper limit pressure value obtained by adding 30s*H(l) to this pressure value 210mHO is set as an absolute upper limit pressure,
For example, it is determined whether or not it exceeds 270 mHg, and if it is within 270 s+HIJ, the process returns to 1 B in FIG. If the upper limit pressure value + 30mtlo set by the upper limit pressure setting switch 11'c exceeds the absolute upper limit pressure, the error indicator light 17 is turned on, the sudden exhaust valve 43 is opened to cause sudden exhaust, and the sound is emitted. to notify the occurrence of an error, and then print out an error message from the printer 36.

If it is determined in the determination step STA that the occurrence of Korotkoff sounds is not recognized, the microcomputer C
The PU determines that the condition for blood pressure measurement has been reached, searches the program table stored in the memory circuit 25, determines the frequency of the drive signal for the stepping motor 45, and then sends the stepping motor drive circuit 46 a drive signal of the same frequency. Output a signal. Stepping motor drive circuit 4
6 is the stepper motor 4 that applies the drive current corresponding to the same drive signal.
5 is energized and driven, the cam 65 is rotated to press the needle valve 61, and the constant speed exhaust device 51 is put into the exhaust state to lower the cuff pressure at a predetermined speed. During this constant-speed evacuation process, the microcomputer CPU recognizes blood vessel sounds, first moving to roller 1]. - Then, the systolic blood pressure value (5YSTO1, IC) is displayed on the LED display 7. After that, continue to recognize blood vessel sounds and confirm the occurrence of Korotkoff sounds. - When confirming that the clicking sound has disappeared from the blood vessel sounds and further confirming that blood vessel sounds without Korotkoff sounds have continued for 3 nights, the microcomputer CPU detects the pressure sensor 23 that corresponds to the last Korotkoff sound. The detected cuff pressure is recognized as the diastolic blood pressure value.The value recognized as the diastolic blood pressure value is displayed on the LED display 8 as the diastolic blood pressure value (DIASTOLIC), and the pulse rate is further displayed on the LED display 9.

After this, the flowchart continues from step 2 in FIG. 6 to step 3 in step 3 in FIG.
Outputs the measured systolic blood pressure value, diastolic blood pressure value, and pulse rate to the ME by voice, and outputs a voice output command signal for skipping. After recognizing the systolic blood pressure value, diastolic blood pressure value, and pulse rate as described above, arrhythmia (IRREGULAR)
If the occurrence of arrhythmia is recognized, the irregular indicator light 16 is turned on, and the
A voice output command signal is outputted to the voice synthesis circuit AME to cause it to output a voice indicating that an arrhythmia has occurred. If the occurrence of arrhythmia is not recognized and the number of measurements set by the number of measurements setting switch 4 is 1, the current measurement information is printed from the printer 36 in digital display form or analog display form, that is, in numbers or graphs. make it out. If the number of measurements set by the number of measurements setting switch 4 is 2 or 3, return to step 1B in FIG. The value is recorded and displayed on the LED display.

(Effects of the invention! As described above, according to the present invention, gas is pumped into the cuff wrapped around the upper arm cap, and after the artery is closed, the state is automatically switched to the exhaust state, and the gas pumped into the cuff is pumped into the cuff. When measuring systolic and diastolic blood pressure during the process of exhausting the cuff, the cuff pressure can be lowered linearly by activating the constant-speed exhaust device and exhausting gas from within the cuff at a predetermined rate. It has the advantage of being able to accurately measure the systolic blood pressure value and the minimum surface pressure value.

[Brief explanation of drawings]

FIG. 1 is a front panel instrument layout diagram of an automatic blood pressure measuring device according to an embodiment of the present invention, FIG. 2 is a calculation control block diagram of this embodiment, FIG. 3 is an overall system diagram of this embodiment, and FIG. The figure is an overall external view of the exhaust system, Figure 5 is a detailed view of its part, and Figure 6 is a detailed diagram of the exhaust system.
1 to 3 in FIG. 6 are flowcharts showing the operation of this embodiment. 1...Automatic blood pressure measuring device CPU...Microcomputer 18...Cuff pressure drop setting switch 23...Pressure sensors 25, 26...Memory circuit 31...Upper arm 32...F) 33 ... Artery 34 ... Microphone 41 ... Pressure pump 45 ... Stepping motor 46 ... Stepping motor drive circuit 61 ... Needle valve 65 ... Cam Applicant: Suzuken Co., Ltd. Person Masaaki Hasu Numa Agent Patent attorney Hidehiko Okada (2 others)

Claims (1)

[Claims] Cuff pressure is used to measure systolic and diastolic blood pressure during the process of pumping gas into a cuff wrapped around the upper arm, closing the artery, and then automatically switching to the exhaust state to exhaust the gas pumped into the cuff. An automatic blood pressure measuring device equipped with an exhaust device for lowering the blood pressure at a preset speed, the pressure chamber portion being in communication with the cuff and formed to obtain a gas pressure equal to the cuff pressure, and the pressure chamber portion having the same pressure. an exhaust part equipped with an exhaust valve for exhausting the gas in the cuff at a predetermined speed through a chamber and lowering the cuff pressure at a preset cuff pressure drop rate; A cam that drives the exhaust valve, a motor that rotates the cam in accordance with the set cuff pressure lowering speed, and a drive control unit that outputs a drive signal corresponding to the set cuff pressure lowering speed to the same motor. A constant-speed exhaust device for an automatic blood pressure monitor, characterized in that the drive control section includes a setting section that outputs a setting signal corresponding to the set cuff pressure lowering speed.