HK1063143B - Bloodless sphygmomanometer - Google Patents

Description

Non-blood-observing sphygmomanometer

Technical Field

The present invention relates to a non-invasive sphygmomanometer, and more particularly to a non-invasive sphygmomanometer capable of calculating a circumferential length of an arm of a subject.

Background

Currently, the most common method for measuring a blood pressure value by a non-blood-viewing method is a method in which a part through which an arm, a wrist, or other artery of a subject passes is externally pressed, blood flow to an elimination part is stopped at one end, and then, changes in コロトコフ sound and pulsation are observed while gradually reducing the pressing pressure, thereby measuring the blood pressure.

The compression of the artery passage portion is performed by externally pressurizing and depressurizing the pressure in the air bubbles by a cuff having the air bubbles of a bag filled with air around the artery passage portion, thereby controlling the stop and reflow of the blood flow to the elimination portion.

However, this method has lower measurement accuracy than the blood observation method in which the intravascular pressure is directly measured. The reason for this is that the blood pressure measurement results are completely different depending on the arm circumference of the subject and the size of the air bubbles used. For example, if the width of the air bubbles (the winding direction and the vertical direction of the arm band) is much shorter than the arm circumference of the subject, the detected blood pressure is higher than the actual value, whereas if the width of the air bubbles is much longer than the arm circumference of the subject, the detected blood pressure is lower than the actual value. Similarly, if the length of the air bubbles (the winding direction of the arm band) is much shorter than the arm circumference of the subject, the detected blood pressure is higher than the actual value, and if the length of the air bubbles is much longer than the arm circumference of the subject, the detected blood pressure is lower than the actual value. Therefore, although it is desirable to prepare air bubbles for the entire subject to obtain an accurate blood pressure value, it is actually difficult to prepare the air bubbles in a medical field for production or the like in view of cost reduction, space guarantee, and the need for an accurate blood pressure value for the subject.

Here, a plurality of arm bands having different bubble sizes are prepared so as to cover the range of the arm circumference of the measurement subject assumed in advance, with the range of the arm circumference having an error within a certain range being used as the range of the arm circumference for use of the bubbles. Thus, in the actual test, (1) the circumference of the arm of the subject is measured by the measuring instrument, and (2) the arm band is selected depending on the intuition of the subject.

However, the method (1) has a problem that the test with the meter takes time, and if there is no meter in the test site, the meter must be searched. Further, in the method (2), there is a problem that an incorrect selection of the cuff or the like is not performed depending on the intuition of the subject.

Here, a method is disclosed that is not troublesome while ensuring accuracy. Specifically, (3) a method of providing a scale indicating the arm circumferential length in the arm band (for example, refer to utility model document 1), (4) a method of providing a test member for measuring the arm circumferential length in the arm band (for example, refer to utility model document 1), (5) a method of providing an arm circumferential length test member in the arm band, for example, providing a variable resistor and other electronic position detecting members in the arm band (for example, refer to patent document 2). (6) A method of estimating the arm circumferential length from the time required for pressurization (for example, refer to patent document 2), specifically, a method of measuring the pressure in a bubble under pressurization and estimating the arm circumferential length of a subject from the time required to reach a predetermined pressure value or the time required to reach a higher predetermined pressure value from a predetermined pressure value is disclosed.

[ patent document 1 ]

JP-A62-152702 (FIGS. 1-5)

[ patent document 2 ]

Japanese patent laid-open publication No. Hei 6-245911 (page 2, FIG. 2)

However, the methods (3) to (6) have the following problems.

In the method (3), it is determined whether or not the air bubbles in the cuff are of a size suitable for the subject from the scale value at the time of winding the cuff around the subject, and the blood pressure value to be tested can be corrected based on the scale value.

In addition, although a method of calculating a blood pressure value with reference to the measured arm circumference length is also conceivable for more accurate measurement, in this case, the blood pressure value is corrected by the human hand, and there is a problem that the arm circumference length must be directly input using the operation button of the sphygmomanometer.

In the method (4), similarly to the method (3), in order to determine whether or not the bubble is appropriately wrapped at the first time, there is a problem that the arm band needs to be wrapped again

In the method (5), although it is possible to obtain an accurate blood pressure value without rewinding the cuff, there are problems in that the structure of the cuff is complicated, the cost is increased, and defective products and defective conditions are frequently generated.

In the method (6), there is a problem that the circumferential length of the arm estimated from the winding strength of the arm band is largely changed.

Disclosure of Invention

In view of the above circumstances, an object of the present invention is to provide a non-blood-observing sphygmomanometer capable of obtaining an accurate blood pressure value without complicating the structure and without taking time and effort.

The non-invasive sphygmomanometer according to claim 1 comprises: an air bag provided in a test site surrounding portion surrounding a test site of a subject or an animal; a pressurization pump that provides gas to the airbag output; a pressure sensor to test the pressure within the air bag; an output amount testing unit for testing the output amount of the pressure pump; and a test site circumference calculation unit configured to calculate a test site circumference of the subject or the animal based on a relationship between the pressure in the air bag measured by the pressure sensor and an output amount measured by the output amount measurement unit, wherein the output amount measurement unit is configured to set a pressure value in the air bag after a space between the test site and the test site surrounding portion is filled with the air bag inflated by the gas output from the pressure pump as a 1 st threshold value and set a pressure value higher than the 1 st threshold value and equal to or lower than a target pressurization set value at the time of the test as a 2 nd threshold value, and the test site circumference of the subject or the animal is calculated using the output amount measured by the output amount measurement unit from the 1 st threshold value to the 2 nd threshold value.

According to the invention described in claim 1, after the output of the pressure pump is measured by the output measuring means, the circumferential length of the test site is calculated by the test site circumferential length calculating means using the relationship between the output and the change in the pressure in the airbag. If the circumferential length of the test site is increased, the output is increased until a predetermined pressure is reached at which the actual volume of the gas bag is increased at the portion of the increased length, so that the circumferential length of the test site can be easily estimated if the relationship between the output of the pressure pump and the pressure in the gas bag is determined in advance. Furthermore, the relationship between the output from the pressure pump and the pressure in the air bag is widely obtained in advance, and it is possible to eliminate the work of reducing the replacement of the test site surrounding portion so as to fit the circumferential length of the test site, and the like. At the same time, the output quantity testing means utilizes the pressure value of 2 points specified in the air bag after the air bag is inflated to fill the space between the testing part and the surrounding part of the testing part, and tests the output quantity of the pressure pump between the pressure values. In this case, even if the gas flows into the bag after the bag is inflated to fill the space between the test site and the test site surrounding portion, the change in volume in the bag is suppressed by the test site and the test site surrounding portion, and therefore the pressure in the bag increases in proportion to the output of the pressure pump. Therefore, the output of the pressure pump is measured using the pressure values in the proportional relationship, and the circumferential length of the test site can be accurately calculated.

The non-blood-observing sphygmomanometer according to claim 2 is characterized in that: in the non-invasive sphygmomanometer according to claim 1, the pressure pump is provided with a rotation number detecting means for counting the rotation number of the motor for the pressure pump as the output amount testing means, and the output amount of the pressure pump is calculated by counting the rotation number of the motor based on the output of the rotation number detecting means.

According to the invention described in claim 2, the number of rotations of the motor for the pressure pump is counted based on the output of the rotation number detecting means, and the output amount of the pressure pump is calculated in accordance with the number of rotations. In the pressure pump having a fixed cylinder volume, since a fixed amount of gas is output in accordance with the number of revolutions, the accurate pressure pump output amount can be calculated by counting the number of revolutions.

The non-invasive sphygmomanometer according to claim 3 includes: an air bag provided in a test site surrounding portion surrounding a test site of a subject or an animal; a pressurization pump that provides gas to the airbag output; a pressure sensor to test the pressure within the air bag; a rotation number detecting unit that counts the rotation number of a motor of the pressure pump; a test portion circumference calculating means for calculating the circumference of the test portion of the subject or the animal based on a relationship between the pressure in the air bag measured by the pressure sensor and the number of rotations of the motor counted by the number-of-rotations detecting means, the rotation number detecting means is configured to inflate the gas bag by the gas output from the pressure pump, the air bag sets the pressure value in the air bag after the space between the test part and the surrounding part of the test part is filled up as the 1 st threshold value, and setting a pressure value which is higher than the 1 st threshold and is equal to or lower than a target pressurization set value at the time of the test as a 2 nd threshold, and calculating the circumference of the test site of the subject or the animal using the number of rotations of the motor counted by the number-of-rotations detecting means from the 1 st threshold to the 2 nd threshold.

According to the invention described in claim 3, after the number of rotations of the motor of the pressure pump is counted by the rotation number detecting means, the circumferential length of the test site is calculated by the test site circumferential length calculating means using the relationship between the number of rotations and the change in pressure in the air bag. In a pressure pump of a type in which a predetermined amount of gas corresponding to the number of rotations of a motor is discharged from a cylinder in the pressure pump until the output amount reaches a predetermined pressure at which the actual volume of the gas bag becomes large if the circumferential length of the test portion becomes long, the circumferential length of the test portion can be easily estimated if the relationship between the number of rotations and the pressure in the gas bag is previously determined. At the same time, the rotation number detecting means inflates the air bag to fill a predetermined pressure value of 2 points in the air bag between the test portion and the test portion surrounding portion, and the rotation number of the motor between the pressure values is measured. At this time, even if the gas flows into the air bag after the air bag is inflated to fill the space between the test site and the test site surrounding portion, the change in the volume in the air bag is suppressed by the test site and the test site surrounding portion, and therefore the pressure in the air bag rises in proportion to the number of rotations of the motor in the pressurizing pump in which the cylinder volume is fixed. Therefore, the number of rotations of the motor is measured using the pressure values in the proportional relationship, and the circumferential length of the test site can be accurately calculated.

The non-blood-observing sphygmomanometer according to claim 4 is characterized in that: in any one of the non-blood-observing sphygmomanometers according to claims 1 to 3, a test result correction means is provided for correcting a blood pressure test result based on the test site circumference of the subject or the subject animal calculated by the test site circumference calculation means.

According to the invention described in claim 4, the blood pressure test result is corrected based on the circumferential length of the measurement site of the subject calculated by the measurement site circumferential length calculating means.

Drawings

Fig. 1 is an explanatory diagram showing an embodiment of a non-invasive blood pressure monitor according to the present invention.

Fig. 2 is an explanatory diagram showing a method of using the non-invasive blood pressure monitor.

Fig. 3 is an exploded view showing details of the pressurizing pump.

Fig. 4 is an explanatory view showing a rotor.

Fig. 5 is an explanatory view showing the 1 st cylinder part of fig. 3.

Fig. 6 is a circuit diagram showing a photocoupler including the fig. 3.

Fig. 7 is a block diagram of the non-invasive sphygmomanometer of fig. 1.

Fig. 8 is a graph showing the relationship between the actual volume of the bubble and the arm circumference.

Fig. 9 is a graph showing a relationship between the number of rotations of the motor and the arm circumference.

Fig. 10 is a graph comparing when the cuff band of fig. 1 is tightly rolled and when the cuff band is slightly loosely rolled.

FIG. 11 is a correction table for Ragan & Bordley.

Detailed Description

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is an explanatory diagram showing an example of a non-invasive blood pressure monitor according to the present invention. The non-blood-observing sphygmomanometer 1 includes a sphygmomanometer body 3 and a cuff 9 as a test site surrounding portion that surrounds a test site of a subject. The cuff 9 is provided with air cells 8 of an air bag for supplying air from the sphygmomanometer body 3 through the plug 5 and the tube 7. In addition, a reinforcing tape (マジツクテ - プ) (registered trademark) 6 is provided in the armband 9 for preventing the armband 9 from being loosened after being wound around the arm of the subject.

The sphygmomanometer body 3 includes a connector 10 for inserting the plug 5, a slow leak valve 11 for adjusting a slow leak speed at the time of testing blood pressure, and a pressurizing pump 13 for feeding air into the air bubbles 8. The sphygmomanometer body 3 further includes a pressure sensor 15 for measuring the pressure in the air bladder 8, a tube 19 for connecting the above-mentioned components, and a joint 21. The sphygmomanometer body 3 further includes a power switch 22 on the outer side surface thereof.

Next, a method of using the non-invasive blood pressure monitor 1 will be described with reference to fig. 2. First, the power switch 22 of the sphygmomanometer body 3 is turned on. Then, the arm of the subject is relaxed, and the arm band 9 is wound around the upper arm of the subject by the subject himself or a tester other than the subject. Next, the maximum pressure value to be applied to the air cell 8 corresponding to the approximate maximum blood pressure value of the subject is determined by operating the button 18. Thus, if the start button 20 is operated, air flows from the sphygmomanometer body 3 into the air bubble 8 through the tube 7, and the blood pressure test starts. Further, the monitor 16 displays the pressure change in the bubble 8 under test, the maximum blood pressure value and the minimum blood pressure value of the test result, and the like. After the blood pressure test is finished, the pulse or the like may be displayed.

Next, the pressurizing pump 13 will be described in detail with reference to fig. 3, and the pressurizing pump 13 includes a motor 23 as a driving source for outputting air. The rear end of the motor 23 is provided with 2 electrodes 23a, and the motor 23 is started by applying a DC6V voltage, for example, to the 2 electrodes 23 a. A rotary shaft 23b protrudes from the front end of the motor 23, and a resin rotor 25 having a fitting hole 25a formed at the center thereof is fitted into the rotary shaft 23 b. In the rotor 25, a fitting hole 25b is formed in a surface of the rotor opposite to the opening side surface of the fitting hole 25 a. The fitting hole 25b is formed to be offset from the center axis Z. Further, the rotor 25 is provided with a thin shielding plate 25c having a fan-shaped outer periphery, and is formed integrally with the rotor main body 25 d.

A cup-shaped cylindrical portion 27 is provided on one side of the rotor 25, and a through hole 27a through which the rotor 25 can be inserted is formed in the cylindrical portion 27. The cylindrical portion 27 is inserted through the bolts 29 through 2 through holes 27d (provided vertically on the paper) formed in the bottom portion 27e, and is screwed into the internal thread 23c formed in the motor 23 to be fixed to the motor 23. Further, a photo-interrupter 31 as a component of a rotational number detecting member for counting the rotational number of the motor 23 is provided in the cylindrical portion 27.

The photo-interrupter 31 is fixed by welding a photo-coupler 31b having a concave cross section to the electrode substrate 31 a. In this 31b, a light emitting diode 33 and an NPN-type phototransistor 35 shown in a circuit 55 of fig. 6 described later are provided, and light passes from one side of the groove to the other side. If the motor 23 rotates once, the shielding plate 25c formed in the rotator 25 passes through the groove, blocks the light of the light emitting diode 33, and counts the number of rotations of the motor 23. In addition, the wire harness 37 is connected to the electrode substrate 31 a.

A cylindrical suction portion 38 is provided on one side of the cylindrical portion 27. The cylindrical suction upper portion 38 includes a metal core rod 41 fitted into the fitting hole 25b and a cylindrical suction portion 43, and the cylindrical suction portion 43 includes a resin cylindrical portion 43a into which the core rod 41 is press-fitted and 3 fork plate portions 43b integrally formed with the cylindrical portion 43 a. In each of the 3 fork plate portions 43b, a rubber-made cylinder suck-up projection 45 is provided, and the rubber-made cylinder 40 provided in the cylinder portion 39 is suck-up deformed by the cylinder suck-up projection 45.

A nozzle 49 is provided on one side of the cylindrical portion 39. The nozzle 49 has a discharge hole 49 a. Thus, if the rubber cylinder 40 is deformed, the air in the cylinder 40 is pushed out to flow through the ejection hole 49 a. Since the mandrel 41 is fitted into the fitting hole 25b formed in the cylinder 40 so as to be displaced from the center axis Z, the cylinder suction portion 43 moves eccentrically and the cylinder 40 made of rubber is sucked up.

Fig. 4 is a front view of the rotor 25 of fig. 3 when viewed from one side. As described above, the fitting hole 25b is formed at a position different from the center of the rotor main body 25 d. Thus, the fan-shaped shielding plate 25c is formed on the outer periphery of the rotor body 25d at a position separated from the fitting hole 25 b.

Fig. 5 is a front view of the tube portion 27 of fig. 3 as viewed from one side. A through hole 27a having the same shape as the rotor 25 when viewed from the front is formed in the bottom 27e of the cup-shaped cylindrical portion 27, and the rotor 25 can be inserted therethrough. Further, through holes 27d are formed on both sides of the through hole 27a, and a through hole 27f for inserting the photo coupler 31b passing through the photo interrupter 31 is formed below.

Fig. 6 is a circuit diagram including the photocoupler 31 b. The circuit diagram 55 includes a power supply 57, resistors 59, 61, 63 and a variable resistor 65. In the power supply 57, DC3V is used. Further, the light emitting diode 33 is connected to a resistor 59, and the phototransistor 35 is connected to a resistor 61. A collector of the NPN transistor 67 is connected to the resistor 63, and a base of the NPN transistor 67 is connected to the resistor 61. In this way, the waveform shaping circuit 75 for outputting a rectangular wave is formed by the resistors 61 and 63, the variable resistor 65, and the NPN transistor 67.

If circuit 55 is powered by power supply 57, current flows through resistor 59 into light emitting diode 33 and light emitting diode 33 is illuminated. Here, the shielding plate 25c attached to the rotor 25 supplies light emitted from the light emitting diode 33 to the base of the phototransistor 35 without shielding the space between the light emitting diode 33 and the phototransistor 35, and the collector and the emitter of the phototransistor 35 are electrically connected to each other, and no current is supplied to the base of the NPN transistor 67. Therefore, the collector and emitter of NPN transistor 67 are turned off, and output voltage Vout becomes substantially 3V of the power supply voltage.

However, if the motor 23 rotates and the shielding plate 25c of the rotor 25 comes to a position where it shields the light beam between the light emitting diode 33 and the phototransistor 35, the collector and the emitter of the phototransistor 35 are turned off by shielding the light energy emitted from the light emitting diode 33 supplied to the base of the phototransistor 35, and as a result, a current is supplied to the base of the NPN transistor 67 through the variable resistor 65 and the resistor 61, the collector and the emitter of the NPN transistor 67 are turned on, and the output voltage Vout becomes substantially 0V.

Therefore, the output voltage Vout repeatedly switches between 0V and 3V in synchronization with the rotation of the motor 23.

Therefore, if the number of changes in the voltage Vout is counted, the shielding plate 25c counts the number of times light emitted from the light emitting diode 33 to the phototransistor 35 is shielded, and the number of rotations of the motor 23 can be counted.

The variable resistor 65 is used to adjust the variation in the amplification factor of the phototransistor 35.

Fig. 7 is a block diagram of the non-invasive sphygmomanometer 1. The process of calculating blood pressure is illustrated using this block diagram. First, the power switch 22 (shown in fig. 1) is turned on, and the power source 68 supplies power to the power circuit 69. Thus, power is supplied from the power supply circuit 69 to various circuits, the pressure pump 13, and the like. Next, as described with reference to fig. 2, the arm band 9 is wound around the upper arm of the subject, the condition for the blood pressure test is set by the operating buckle 18, and then the start buckle 20 is pressed.

Then, the pressure pump 13 is activated in response to a signal from the CPU71, and air is sent to the air bubbles 8 provided in the arm band 9. When the pressure in the air bubbles 8 rises to a set value, the slow leak valve 11 is in a half-open state, and the air in the air bubbles 8 is gradually released to the atmosphere, and the pressure is gradually reduced at a predetermined speed. The pressure in the bubble 8 is observed by the pressure sensor 15, and a pulse of which frequency changes in accordance with the observed pressure value is output. The pulse is converted into a pressure value by the pressure test circuit 73, and is displayed on the monitor 16 at predetermined time intervals in real time. The slow leak valve 11 is fully opened after the blood pressure test is completed, and the pressure in the air bubbles 8 is rapidly reduced.

The waveform of the output voltage Vout of the circuit 55 (shown in fig. 6) including the photointerrupter 31 and the waveform shaping circuit 75 is input to the revolution number counter circuit 77 as an internal circuit of the CPU 71. Thus, the number of rectangular waves generated by the waveform shaping circuit 75 from the time when the pressure in the bubble 8 reaches the 1 st threshold to the time when the pressure decreases to the 2 nd threshold is counted by the revolution count circuit 77. Here, the 1 st threshold value is a value after the bubble 8 has inflated to fill the space between the upper arm and the arm band 9. That is, the pressure in a state where the change in the pressure measured by the pressure sensor 15 and the output amount of the pressurizing pump 13 are in a proportional relationship is used as the 1 st threshold value. For example, 40mmHg is set. On the other hand, the 2 nd threshold is set to a value higher than the 1 st threshold and equal to or lower than the target pressurization value at the time of the test. For example, 160mmHg is set. The target pressurization value during the test is set to a value higher by 30 to 40mmHg than the predicted maximum blood pressure value of the subject, for example.

In addition, the revolution number detecting means includes the photointerrupter 31, the waveform shaping circuit 75, and the revolution number counting circuit 77.

Next, the output quantity calculation circuit 78 calculates the output quantity from the number of counts of the rectangular wave by the rotation number counting circuit 77, that is, the number of rotations of the motor 23 (shown in fig. 3). The output quantity calculating means is constituted by the output quantity calculating circuit 78 and the above-described revolution number detecting means.

Next, in the arm circumferential length detection circuit 79 of the test site circumferential length detection means, the arm circumferential length is calculated from the output amount calculated by the output amount calculation circuit 78 from the 1 st threshold value to the 2 nd threshold value of the pressure in the bubble 8. The reason why the circumferential length of the arm is estimated as described above is that the actual volume in the bubble 8 increases as the circumferential length of the arm increases, and the amount of air necessary for increasing to a predetermined pressure increases. Fig. 8 shows the relationship between the actual volume of the bubble 8 and the arm circumference. It can be seen that the actual volume of the bubble 8 becomes substantially proportionally greater if the arm circumference becomes longer, as measured between 190mm and 345 mm. Fig. 9 shows a relationship between the number of rotations of the motor 23 and the arm circumference. Since the air output amount is fixed for one rotation of the motor 23, the curve is the same as that of fig. 8.

Fig. 10 shows the relationship between the number of rotations of the motor 23 and the pressure in the bubble 8 according to the winding method of the cuff 9. In the same figure, the arm band 9 is wound around a subject whose arm circumference is 260mm and pressed to 180 mmHg. The black dot mark is a winding form when the arm band 9 is wound tightly around the arm of the subject to perform a normal test. On the other hand, the black triangular mark is slightly loosely wound. As can be seen from the figure, the way of slightly loosely wrapping the cuff 9 increases the actual volume inside the bubble 8 compared to tightly wrapping the cuff 9, so the cumulative number of revolutions to reach the same pressure becomes larger.

However, the slopes of both the curves are the same in that they are substantially linear on the boundary of approximately 40 mmHg. This means that the pressure in the cells 8 reaches 40mmHg, and the cells 8 fill the space between the test site and the cuff 9. Therefore, if the 1 st threshold and the 2 nd threshold are employed widely at the 2 nd point width of the straight line, the arm circumferential length with good accuracy can be estimated.

Next, the blood pressure value correction circuit 81 of the test result correction means corrects the blood pressure test result based on the arm circumference length of the subject calculated by the arm circumference length detection circuit 79. Specifically, the Ragan & Bordley correction table shown in fig. 11 and the Pickering correction formula are applied. Moreover, the modified expression of Pickering means:

s＝1.27c-35.86 ： d＝0.87c-15.54

s: maximum blood pressure value (mmHg) c: upper arm circumference (mm) d: lowest blood pressure value (mmHg)

In the table of fig. 11, when the bubble 8 having a width of 13cm is used, the maximum blood pressure value and the minimum blood pressure value are changed according to the circumferential length of the upper arm. For example, a subject whose upper arm circumference is 240mm is corrected by adding 5mmHg to the maximum blood pressure value of the test and subtracting 5mmHg from the minimum blood pressure value.

Finally, the corrected maximum blood pressure value and minimum blood pressure value are displayed on the monitor 16, and the test is completed.

As described above, according to the embodiment of the present invention, the output of the pressure pump 13 is measured by detecting the number of rotations of the motor 23 by the photo-interrupter 31, and then the arm circumferential length is calculated by the arm circumferential length detection circuit 79 using the relationship between the output and the change in the pressure in the bubble 8. If the arm circumferential length is increased, the output is increased to increase the actual volume of the long bubble 8 to a predetermined pressure, and if the relationship between the output of the pressure pump 13 and the pressure in the bubble 8 is obtained in advance, the arm circumferential length can be easily estimated. Therefore, the present invention can be implemented by providing the photointerrupter 31 in the pressure pump 13 and further performing a simple design change of only providing the circuits such as the waveform shaping circuit 75 and the revolution number counting circuit 77, and the arm circumference length can be estimated without complicating the configuration. Then, if the blood pressure value is corrected by the blood pressure value correction circuit 81 according to the arm circumference, an accurate blood pressure value can be obtained. Furthermore, if the relationship between the output of the pressure pump 13 and the pressure in the air cells 8 is obtained over a wide range, the work of replacing the cuff 9 or the like in accordance with the arm circumference is reduced, and therefore a blood pressure test can be performed without trouble.

In addition, since the output of the photointerrupter 31 is input to the blood pressure value correction circuit 81 via the waveform shaping circuit 75, the revolution number counting circuit 77, the output amount calculating circuit 78, and the arm circumference length detecting circuit 79, the blood pressure test can be automatically performed. Therefore, the blood pressure test can be performed quickly without taking a lot of time and effort, without directly inputting the measured arm circumferential length to the non-blood-observing sphygmomanometer 1.

Although the output amount is calculated from the number of rotations of the motor 23, the output amount can be calculated accurately because the volume of the cylinder 40 is fixed. Conventionally, since the output amount is calculated by the rotation time of the motor 23, an error occurs due to a change in output of the battery with time, and although the output of the battery is fixed, an error occurs due to a change in load due to a change in pressure in the bubble 8.

Further, according to an embodiment of the present invention, the output of the pressure pump 13 between 2 pressure values is tested by using 2 pressure values in the air bubble 8 after the air bubble 8 is inflated to fill the space between the arm and the arm band 9, and even if air flows into the air bubble 8 after the air bubble 8 is inflated to fill the space between the arm and the arm band 9, the change in the volume in the air bubble 8 is suppressed by the arm and the arm band 9, the pressure in the air bubble 8 rises in proportion to the output of the pressure pump 13, and the correct arm circumference can be calculated by using the pressure values in the proportional relationship. Therefore, it is possible to prevent an error in the test result from being generated by loosely winding the arm band 9.

In the above-described embodiment, the example in which the arm band 9 of the test portion is wound around the upper arm of the subject has been described, but the present invention is not limited thereto. For example, the device may be wrapped around the wrist or other parts of the foot.

In the above-described embodiment, the example in which the armband 9 is wound around the subject has been described, but the subject may be an animal.

In the above-described embodiment, the example in which air is introduced as the gas into the bubbles 8 has been described, but other gases may be used.

In the above-described embodiment, the example has been described in which the output amount is calculated by the output amount calculation circuit 78 after the rotation number of the motor 23 is counted by the rotation number counting circuit 77, and the arm circumferential length is estimated by the arm circumferential length test circuit 79, but the relationship between the rotation number of the motor 23 and the arm circumferential length between the pressure values at 2 points may be obtained in advance, and the arm circumferential length may be estimated without calculating the output amount.

As described above, according to the present invention, after the output amount of the pressure pump is measured, the arm circumferential length is calculated by the test site circumferential length calculating means using the relationship between the output amount and the change in the pressure in the air bag, and if the arm circumferential length is increased, the output amount is increased to increase the actual volume of the air bag to a predetermined pressure, and if the relationship between the output amount of the pressure pump and the pressure in the air bag is previously obtained, the arm circumferential length of the test site can be easily estimated. Therefore, for example, the present invention can be implemented by providing a rotation number detecting means in the pressure pump to measure the output amount and by simply changing the design, and the arm circumference length can be estimated without complicating the structure. And if the blood pressure value is corrected by the test result correcting means based on the arm circumference, a correct blood pressure value can be obtained. Furthermore, if the relationship between the output from the pressure pump and the pressure in the air bag is widely adopted, the work of replacing the test site surrounding portion in accordance with the arm circumference is reduced, and thus an accurate blood pressure value can be obtained without trouble.

Claims (4)

1. A non-spectacular sphygmomanometer comprising:

an air bag provided in a test site surrounding portion surrounding a test site of a subject or an animal;

a pressurization pump that provides gas to the airbag output;

a pressure sensor to test the pressure within the air bag;

an output amount testing unit for testing the output amount of the pressure pump;

a test site circumference calculation unit that calculates the circumference of the test site of the subject or the animal based on a relationship between the pressure in the airbag measured by the pressure sensor and the output measured by the output measurement unit,

the output amount test means sets a pressure value in the airbag after the space between the test site and the test site surrounding portion is filled with the gas output from the pressure pump to a 1 st threshold value and sets a pressure value higher than the 1 st threshold value and equal to or lower than a target pressurization set value at the time of the test to a 2 nd threshold value, and calculates the test site circumference of the subject or the animal using the output amount tested by the output amount test means from the 1 st threshold value to the 2 nd threshold value.

2. The non-invasive sphygmomanometer according to claim 1, wherein:

as the output amount testing means, a rotation number detecting means for counting a rotation number of a motor for the pressure pump is provided in the pressure pump,

the number of rotations of the motor is counted based on the output of the rotation number detection means, and the output amount of the pressure pump is calculated.

3. A non-spectacular sphygmomanometer comprising:

an air bag provided in a test site surrounding portion surrounding a test site of a subject or an animal;

a pressurization pump that provides gas to the airbag output;

a pressure sensor to test the pressure within the air bag;

a rotation number detecting unit that counts the rotation number of a motor of the pressure pump;

a test portion circumference calculating means for calculating the circumference of the test portion of the subject or the animal based on a relationship between the pressure in the air bag measured by the pressure sensor and the number of rotations of the motor counted by the number-of-rotations detecting means,

the rotation number detecting means sets a pressure value in the air bag after the air bag is inflated by the gas output from the pressure pump to a 1 st threshold value after a space between the test site and the test site surrounding portion is filled, sets a pressure value which is higher than the 1 st threshold value and is equal to or lower than a target pressure setting value at the time of the test to a 2 nd threshold value, and calculates the circumference of the test site of the subject or the animal using the rotation number of the motor counted by the rotation number detecting means from the 1 st threshold value to the 2 nd threshold value.

4. A non-invasive sphygmomanometer according to any one of claims 1 to 3, wherein:

and a test result correcting means for correcting a blood pressure test result based on the test site circumference of the subject or the animal to be tested calculated by the test site circumference calculating means.