JPH0239248B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention involves wrapping a cuff band around the arm and applying pressure.
The present invention relates to an exhaust valve for controlling the rate of blood pressure reduction in a blood pressure monitor that measures blood pressure by detecting Korotkoff sounds during blood pressure reduction.

[Background Art] In a blood pressure monitor, the pressure of the cuff band is gradually lowered when measuring blood pressure, and it is desired that blood pressure be lowered at a constant rate regardless of the pressure value as a condition for accurate measurement. An example of realizing this condition with a simple configuration is disclosed in Japanese Utility Model Application Publication No. 55-21729. This is an elastic cylindrical member that partitions the pressure pump side and the cuff band side, and a needle-like member is attached to the end face of this cylindrical member so that pressure from the cuff band side is applied to the outer circumferential surface. The opening area of the ventilation gap created around the needle-like member by penetrating the needle-like member changes depending on the pressure value on the cuff band side applied to the cylindrical member. It is something. In other words, when the pressure on the cuff band side is high, the area of the ventilation gap is small, and when the pressure is low, the area of the ventilation gap returns to its original size and becomes larger. However, with this type of device, there is a risk that the needle-like member may shift or come off, and if the exhaust valve of this type is built into the rubber ball-shaped pressurizing pump section, the needle-like member may become misaligned due to the handling. There is a higher risk of it slipping off or coming off. If the needle-shaped member is not in the correct position, the pressure will not be lowered at the prescribed rate.
This made it impossible to accurately measure blood pressure. In addition, the area of the ventilation gap is set according to the rate of pressure reduction, as exhaust during pressure reduction is performed from this exhaust valve through the pressure pump, and air is also supplied to the cuff band from the pressure pump through the exhaust valve. Therefore, a large amount of force was required to operate the pressurizing pump to send air into the cuff band.

[Objective of the Invention] The present invention has been made in view of the above points, and its purpose is to lower the blood pressure at a constant rate regardless of the pressure value, and to maintain a stable state over a long period of time. To provide an exhaust valve for a sphygmomanometer, which can control the blood pressure lowering speed with a pressure pump, and requires less force to operate the pressurizing pump when air is sent from the pressurizing pump to the cuff band through the exhaust valve. It is in.

[Disclosure of the Invention] The present invention has a bottomed cylindrical shape with one end closed, and is provided with a first slit in the side wall that opens under applied stress to communicate the cuff band side and the pressurizing pump side. and an elastic sleeve having a second slit at one closed end thereof, the one closed end having the second slit of the elastic sleeve having a bottomed cylindrical shape is located on the opposite side from the pressurizing pump, and One end of this is a surface that is perpendicular to the direction of travel of the air flow from the pressure pump or a hemispherical surface that is concave with respect to the direction of travel of the air from the pressure pump. It is characterized by a structure in which the second slit is formed to extend from the closed end surface of the elastic sleeve to the side wall, and the first slit changes the opening area according to the pressure value on the cuff band side, reducing the pressure. The speed is controlled so that when air is sent from the pressure pump to the cuff band, the air passes not only through the first slit but also through the second slit, which is opened by the pressure inside the pressure pump.

The present invention will be described in detail below based on illustrated embodiments. First, the overall structure of the blood pressure monitor will be explained. In the figure, 1 is a cuff band, 2 is a main body, and these two and a manual pressure pump 3 constitute the blood pressure monitor. The pressurizing pump 3 includes an exhaust mechanism 4 and is connected to the cuff band 1 via the main body 2 by an air pipe 22. A rectangular main body 2 arranged and fixed on the surface of the cuff band 1 is a housing 2 whose lower surface is curved.
A printed circuit board with electrical circuit components mounted thereon, a pressure sensor 27, a battery, etc. are housed inside the cuff 1, and a digital blood pressure display 10 is provided on the surface of the cuff 1. When the cuff band 1 is attached across the arm and wrapped around the arm,
The longitudinal direction of the main body 2 is made to coincide with the direction of the arm. Further, the length of the cuff band 1 in the width direction of the main body 2 is made smaller than the width of the cuff band 1 so that the main body 2 does not protrude from the cuff band 1.

The cuff band 1 is formed by high-frequency welding the edges of multiple sheets made of soft vinyl chloride resin, etc., and houses a microphone 9 for detecting Korotkoff sounds connected to a printed circuit board in the main body 2. It is being Further, a binding band portion 11 extends from one end of the cuff band 1. The cuff band part 11 is smaller in width than the cuff band 1, and has a plurality of elongated holes 30 which are long in the width direction and are spaced apart in the longitudinal direction, and the cuff band part 11 covers the entire surface of the inner surface. A planar fastener F2 that engages with the planar fastener F1 at one end of the fastener F2 is provided. Also, the binding part 11
Also provided on the outer surface of the free end is a planar fastener F3 that engages with the planar fastener F1.

When attaching the cuff band 1 to the arm, the cuff band 1 is first temporarily attached to the arm using the elasticity of an elastic curved plate (not shown) built into the cuff band 1, and then the cuff band 11 is attached to the inner surface of the cuff band 11. The planar fastener F2 is engaged with the planar fastener F1 of the cuff band 1, and the planar fastener F3 attached to the outer surface of the free end of the folded binding band part 11 is inserted into the cuff through the elongated hole 30 of the binding band part 11. By engaging with the planar fastener F1 of the band 1, the excess binding band part 11 is stopped. In this state, if air is sent into the cuff band 1 from the pressurizing pump 3 connected to the main body 2, the compression bag portion of the cuff band 1 will be inflated, and the pressure in the compression bag portion at this time will be The Korotkoff sound is detected by the sensor 27, and the Korotkoff sound is detected by the microphone 9, and both detection outputs are output from the amplifier circuit 23, the Korotkoff sound discrimination filter 24, the level detection circuit 25, and the operation as shown in FIG. Control circuit 26, pressure sensor 27, and analog/digital conversion circuit 28
The blood pressure value is processed and displayed on the digital display section 10. 29 is a memory circuit for storing the systolic blood pressure value and the diastolic blood pressure value; 5 is an exhaust valve for gradual exhaust; and 12 is a rapid exhaust valve for rapidly lowering the pressure in the cuff band 1 after measuring the blood pressure value. .

Now, the exhaust mechanism 4 is equipped with an exhaust valve 5 and a quick exhaust valve 12, and as shown in FIG. It is arranged between the air pipe 22 and the pressurizing pump 3 which has an intake valve 33 at its rear end. The exhaust valve 5 is located inside the pressurizing pump 3, and the rapid exhaust valve 12 is located inside the exhaust valve 5.
and the air pipe 22. The quick exhaust valve 12 is provided in the middle of the ventilation pipe 14 housed in the housing 13.
a spherical valve body 37 that is slidable in a direction perpendicular to the axial direction of the valve body 4 and is biased by a spring 36 in a direction in which it comes into contact with an O-ring 35; and an exhaust port formed in the middle of the ventilation pipe 14. The push button 38 is in contact with the valve body 37 through the
The exhaust port is closed by contact with the O-ring 35, and when the push button 38 is pressed and the valve body 37 is pushed down, the exhaust port opens. Note that both ends of the ventilation pipe 14 are communicated via a detour that bypasses the rapid exhaust valve 12. In addition, the intake valve 33 in the pressurizing pump 3
is not a perfect check valve, and when the pressure increase in the pressure pump 3 is gradual, the air in the pressure pump 3 is released to the atmosphere through the intake valve 33.

An exhaust valve 5 that gradually removes the air in the cuff band 1 to lower the pressure during blood pressure measurement is formed of an elastic sleeve 6 housed inside one end of the vent pipe 14. As shown in FIGS. 3 to 5, this elastic sleeve 6 has a cylindrical shape with one end closed, and has a flange 40 on the periphery of the opening at the other end. A plurality of first slits 7 are formed in the air pipe 14, a second slit 17 is formed in one closed end surface, and the outer diameter is the same as that of the elastic sleeve 6 in the ventilation pipe 14.
The flange 40 is housed in the ventilation pipe 14 so that the outer circumference of the flange 40 comes into contact with the step on the inner surface of the ventilation pipe 14, and the opening of the ventilation pipe 14 An adjusting screw 8 screwed into the elastic sleeve 6 presses the inner circumference of the opening of the elastic sleeve 6 in the axial direction via a ring-shaped retainer 9 made of a slippery material such as polyacetal resin. The first slit 7 in the elastic sleeve 6 is opened by the stress of the elastic sleeve 6 generated by the pressing force applied from the adjustment screw 8, and communicates the inside of the pressurizing pump 3 with the cuff band 1 side. . Here, the second slit 1 of the elastic sleeve 6
The closed end with 7 is located on the opposite side to the pressure pump 3, and this end has a hemispherical shape that is perpendicular to the direction of movement of the air flow from the pressure pump 3 or concave in the direction of movement. As shown in FIG. That is, in the embodiment shown in FIGS. 2 to 5 and 8, the closed end of the elastic sleeve 6 with the second slit 17 is perpendicular to the direction of flow of air from the pressurizing pump 3. By being a flat surface, this part becomes a non-projecting surface with respect to the direction of flow of air from the pressure pump 3, and in the embodiment shown in FIG. 9, the second slit 17 of the elastic sleeve 6 is provided. The closed end has a hemispherical shape that is concave with respect to the direction of flow of air from the pressure pump 3, so that this part is a non-protruding surface with respect to the direction of flow of air from the pressure pump 3. The second slit 17 will not open due to distortion caused by the stress of the elastic sleeve 6. In other words, although shown in the drawing as open, both the first slit 7 and the second slit 17 are actually closed in the elastic sleeve 6 alone, and the stress caused by the pressure applied from the adjustment screw 8 causes the first slit 7 and the second slit 17 to close. Only the slit 7 is open. The opening area of the first slit 7 can be adjusted by turning the adjusting screw 8 to change the pressing force. At this time, since the presser 9 is interposed between the adjustment screw 8 and the elastic sleeve 6, the elastic sleeve 6 will not be twisted.

When you hold the pressure pump 3 in your hand and inflate and deflate it,
The air flowing into the pressurizing pump 3 from the intake valve 33 passes through the open first slit 7 of the elastic sleeve 6 while further expanding it, and also passes through the closed second slit 17 while expanding it. It is sent to the cuff band 1 through the main body 2. At this time, the second slit 17 is located in the advancing direction of the air flow from the pressure pump 3 and is formed to extend from the end surface to the side surface of the elastic sleeve 6, so that the pressure inside the pressure pump 3 is Since it is made easier to open by rising the pressure pump 3, the force required to operate the pressurizing pump 3 is light. Then, when blood pressure is measured, the pressure decreases due to gradual exhaustion through the exhaust valve 5 and the intake valve 3.
It is carried out through 3. During this evacuation, the evacuation is performed only through the first slit 7, which is opened by the stress in the elastic sleeve 6 in order to keep the second slit 17 closed, but the pressure on the cuff band 1 side When the pressure is high, the elastic sleeve 6 is influenced by this pressure and moves through the first slit 7.
In order to reduce the opening area and return to the original opening area when the pressure on the cuff band 1 side decreases, the pressure inside the cuff band 1 is reduced at a constant pressure reduction rate regardless of the pressure value, as shown in Figure 7. It lowers blood pressure. Further, this pressure lowering speed can be adjusted by changing the pressing force applied to the elastic sleeve 6 by the adjusting screw 8.

As is clear from the above, this first slit 7
and a second slit 17.
In the exhaust valve 5 formed of The operating force can be reduced, and the air discharged from the cuff band 1 is allowed to pass only through the first slit 7, thereby making it possible to obtain the required rate of pressure reduction. . Note that the first slit 7 and the extension line from both ends of the second slit 17 on the outer peripheral surface of the elastic sleeve 6 are connected in the circumferential direction.
The reason why they are shifted by 90 degrees is to prevent the elastic sleeve 6 from being damaged by cracks caused by the first slit 7 and the second slit 17.

In order to further reduce the operating force of the pressurizing pump 3, the thickness of the elastic sleeve 6 at the portion where the second slit 17 is provided is made thinner as shown in FIG. As shown in FIG. 2, the closed portion of the elastic sleeve 6 in which the second slit 17 is provided may be formed into a hemispherical shape so that it can be easily opened by the pressure inside the pressure pump 3.

[Effects of the Invention] As described above, in the present invention, the first slit provided in the side wall of the elastic sleeve is opened by the pressure applied to the elastic sleeve, and the cuff side and the pressurizing pump side are opened.
In other words, it communicates with the atmosphere side, and there are no parts such as needle-like members that may slip or come off, and the first slit is opened by the pressure of the cuff band applied to the elastic sleeve. By changing the area, it is possible to obtain a constant pressure reduction rate regardless of the pressure value on the cuff side, and furthermore, when sending air from the pressurizing pump to the cuff side, not only the first slit, Since the second slit formed at the closed end of the elastic sleeve also opens, even if the opening area of the first slit is determined to achieve the desired pressure reduction rate, the pressure applied when air is sent to the cuff band is increased. The operating force of the pressure pump is small, and in particular, the closed end of the elastic sleeve in the shape of a bottomed cylinder is located on the opposite side of the pressure pump, and this end is pressurized. A non-protruding surface with respect to the direction of air flow from the pressurizing pump, such as a surface perpendicular to the direction of travel of the air flow from the pump or a hemispherical surface concave with respect to the direction of travel. Since the two slits are formed to extend from the closed end surface of the elastic sleeve to the side wall, the second slits open only when pressure is applied from the pressure pump, and the pressure pump can be operated with a light force. The second slit can be easily opened by the pressure increase, and the pressure pump can be easily operated.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a blood pressure monitor equipped with an embodiment of the present invention, FIG. 2 is a sectional view of the pressurizing pump and exhaust mechanism of the same, FIG. 3 is an enlarged sectional view of the exhaust valve of the same, and FIG.
The figure is a horizontal cross-sectional view of the same as above, FIG. 5 is a perspective view of the same as above,
FIG. 6 is a block circuit diagram of the blood pressure monitor, FIG. 7 is a pressure-reducing characteristic diagram of the same exhaust valve, and FIGS. 8 and 9 are cross-sectional views of other embodiments, in which 1 is a cuff band, 3 4 is a pressure pump, 4 is an exhaust mechanism, 5 is an exhaust valve, 6 is an elastic sleeve, 7 is a first slit, and 17 is a second slit.

Claims (1)

[Claims] 1. The first slit has a bottomed cylindrical shape with one end closed, and is provided with a first slit in the side wall that opens under applied stress to communicate the cuff band side and the pressurizing pump side. The elastic sleeve is formed of an elastic sleeve having a second slit at one end, and one closed end of the elastic sleeve with the second slit is located on the opposite side of the pressurizing pump, and the one end is A non-protruding surface with respect to the direction of air flow from the pressure pump, such as a surface perpendicular to the direction of travel of the air flow from the pressure pump or a hemispherical surface concave with respect to the direction of travel. An exhaust valve for a blood pressure monitor, characterized in that the second slit is formed to extend from the closed end surface of the elastic sleeve to the side wall. 2. The exhaust valve for a sphygmomanometer according to claim 1, wherein an extension line of the side wall of the elastic sleeve from both ends of the second slit and the first slit are located at different locations in the circumferential direction. 3. The exhaust valve for a blood pressure monitor according to claim 1, wherein one end of the elastic sleeve in which the second slit is formed has a wall thickness that is thinner than the other portion.