JPS5828567Y2 - Exhaust device for blood pressure monitor - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an evacuation device for reducing the pressure within a cuff from an arbitrary value at a constant pressure reduction rate.

The most common type of blood pressure monitor measures blood pressure by wrapping a cuff (air bag) around the upper arm of the patient.
In order to perform stable measurement with high accuracy, it is desirable that the pressure change in the cuff becomes a nearly constant rate of decompression after a predetermined value in the process of exhausting the air in the cuff during measurement.

To do this, after rapidly evacuation to a predetermined value, the opening degree of the exhaust valve is kept relatively small during the initial stage of evacuation when the pressure inside the cuff is relatively high, and as the pressure inside the cuff decreases, the opening of the exhaust valve is It is necessary to perform an adjustment operation to increase the degree of opening.

However, in conventional blood pressure monitors, a flow control valve such as a needle valve consisting of a conical valve body and a cylindrical valve seat installed in the middle of the exhaust path is generally used as the cuff exhaust valve. However, in this type of exhaust valve, the opening area changes quadratically in response to the operation of the operating knob, so the opening area can be adjusted with a constant feeling of operation over the entire adjustment range. First, such operations largely depend on the skill level of the person taking the measurement, and therefore, it is difficult for the general public to maintain a constant cuff decompression rate by operating the exhaust valve as described above. It was extremely difficult.

This idea was made in view of the conventional points mentioned above, and its purpose is to pressurize the cuff to a high pressure and then
It is an object of the present invention to provide an evacuation device that can quickly evacuate the air to a required measurement start pressure, can reduce the pressure at a constant rate of pressure reduction during measurement, and is easy to manufacture.

Hereinafter, one embodiment of this invention will be described in detail based on the drawings.

Figure 1 shows the structure near the air supply rubber bulb of a blood pressure monitor as an application example of the constant speed exhaust valve according to this invention. 1 is a tubular base body, and air circulation holes 2 are formed through it in the longitudinal direction. One end of this air circulation hole 2 is pneumatically connected to a cuff 4 for ischemia via a rubber hose 3 which also serves as a supply and exhaust pipe, and the other end is connected to a blood supply cuff 4 having a check valve 5. A rubber bulb 6 for air is directly connected, and air is forced into the cuff 4 by inflating and deflating the rubber bulb 6.

Further, a socket part 7 having a thread carved on the outer periphery is integrally formed in the intermediate part in the longitudinal direction of the base body 1 so as to be perpendicular thereto, and this socket part 7 has a conical valve seat. It communicates with the air circulation hole 2 through an exhaust hole 9 formed in the portion 8, and at the same time communicates with the atmosphere through a fine exhaust port 10.

11 is a needle valve inserted into the socket part 7;
The conical tip of the needle valve 11 faces the valve seat 8 and is biased upward via a compression spring 12, and its position is restricted by an operating knob 13 screwed onto the socket 7. By rotating this operating knob 13, the needle valve is moved toward and away from the valve seat 8, and as a result, the flow rate of air discharged to the atmosphere through the exhaust port 10 is controlled. There is.

Reference numeral 15 denotes a highly elastic rubber tubular body press-fitted into the end of the base 1 on the rubber ball 6 side, that is, a constant speed exhaust valve 14.
The half of the valve body 15 on the cuff 4 side in the longitudinal direction is formed to have a small diameter so as to maintain a constant gap with the inner wall of the base 1, and the half on the cuff 4 side in the longitudinal direction The end face is completely closed, while the open end face of the conduit 15a on the rubber bulb 6 side opens into the rubber bulb 6.

On the outer periphery of the small diameter portion 15b of the valve body 15, as shown in FIGS. 3 and 4, two sleeves (16.16) are cut in the longitudinal direction with a phase of approximately 180°, as if cut with a sharp knife. They are formed parallel to each other, and the second sleeve is used as an adjustment member to adjust the opening amount of the sleeves (16.16).
16. As shown in the figure and FIG.
16 are held under pressure so that they are shared.

As a result, when air is supplied from the rubber bulb 6 side, the slit 16.16 of the valve body 15 opens due to its internal pressure, allowing air to be supplied to the cuff 4 side, and also allows air to be supplied from the rubber bulb 6 side. When it is stopped, the sleeves 16, 16 close due to their own elastic force and have the function of a check valve that prevents a sudden backflow of air from the cuff 4 side to the rubber bulb 6 side, and at the same time The valve body 15 is a sleeve) 16.16 and the linear member 17 sandwiched therein constitute a constant speed exhaust mechanism, and under normal conditions, the cuff 4 side is completely unaffected by the operation of the operating knob 13. air flows through the linear member 17
is exhausted from the gap between the sandwiched slits 16 and 16 to the atmosphere through the rubber bulb 6 at a constant decompression rate.

That is, when the cuff 4 side including the rubber hose 3 is in a relatively high pressure state, the pressure acts evenly on the circumferential surface of the small diameter portion 15b of the valve body 15 located within the air circulation hole 2 of the base body 1. .

At this time, the higher the pressure inside the air circulation hole 2, the more the pressure is increased in addition to the elastic force of the valve body 15 itself.
The clamping force of 16.16 on the linear member 17 increases, and as a result, air flows from the gap between the slits 16'' and 16 where the linear member 17 is clamped toward the rubber ball 6 side. Large resistance to flow (slit 16
．． 16), the air on the cuff 4 side is continuously exhausted to the rubber bulb 6 side at a constant decompression rate through this small gap.

On the other hand, as the pressure within the air circulation hole 2, that is, on the cuff 4 side, decreases, the pressure acting on the valve body 15 inevitably decreases, and the clamping force of the slit 16.16 against the linear member 17 gradually increases. With only its own elastic force,
The clamping force on the linear member 17 is gradually relaxed, and the resistance to the flow of air through the opening gap of the sleeve 16.16 becomes smaller.

Therefore, due to the constant speed exhaust function that is correlated with the slit 16° 16 and the linear member 17 as described above, a linear constant speed exhaust curve can be obtained over the entire predetermined range of pressure difference required for blood pressure measurement. There is.

In the above configuration, the pumping and exhausting operation will be explained. First, with the needle valve 11 opened and closed by the operation knob 13 closed, the rubber bulb 6 is expanded and contracted (pressurized), thereby causing the valve body to 15 slits 16.
16 is opened, and air is forced into the cuff 4 through the flow hole 2 and the rubber hose 3.

When the pressure inside the cuff 4 reaches a predetermined pressure, the pressurizing operation by the rubber ball 6 is stopped, and the slits 16 and 16 are closed, but as mentioned above, the air on the cuff 4 side is linear. The gap between the slits 16 and 16 created by sandwiching the member 17 is gradually exhausted to the atmosphere side through the rubber bulb 6, and the process shifts to a constant speed exhaust process.

However, when actually measuring blood pressure, it is undesirable to shift to constant-speed exhaust immediately after pressurizing to a predetermined pressure because the time required for measurement will be long. Open the chamber and rapidly evacuate to a pressure that does not interfere with blood pressure measurement.

Therefore, exhaust by operating the operating knob 13 is used exclusively for rapid exhaust.

After this, operate the operation knob 13 again to remove the needle valve 11.
16.16 and linear member 17
A constant-speed exhaustion process occurs due to the correlation with

As is clear from the above description, according to the blood pressure monitor exhaust system of this invention, rapid exhaust and stable constant-speed exhaust can be performed with an extremely simple configuration, and the slope of the constant-speed exhaust curve is also It can be set arbitrarily by selecting the diameter of the linear member used as the adjusting member to adjust the amount, and the complexity of conventional constant speed exhaust can be eliminated at the same time.Furthermore, manufacturing and assembly is easy and costs are reduced. It contributes to

Further, in the embodiment of this invention, the opening amount of the slit is adjusted by directly holding the linear member between the slits, but it is also possible to adjust the opening amount of the slit indirectly.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the structure near the air supply rubber bulb of a blood pressure monitor as an application example of the exhaust device according to this invention, Fig. 2 is a perspective view of only the constant speed exhaust valve, and Fig. 3 is Similarly, FIG. 4 is a sectional view taken along the line 4--4 in FIG. 3. 4... Cuff, 11... Needle valve, 1
4... Constant speed exhaust valve, 15... Tubular body (
valve body), 15b... small diameter part, 16...
Slit, 17... linear member.

Claims (1)

[Scope of Claim for Utility Model Registration] A system for reducing the pressure in a blood pressure cuff for ischemia from an arbitrary value at a constant pressure reduction rate, the system comprising: The pipe is constructed of a flexible member with high elasticity, has cross-sections with different diameters in the longitudinal direction, and is located on the high pressure side of the pipe with its end on the small diameter side closed. , a tubular body whose other end opens on the low pressure side, a pair of slits formed in the longitudinal direction on the small diameter side of the tubular body, and a pair of slits that pass through the slits and are sandwiched by the slits; a constant-speed exhaust valve consisting of a ring-shaped fine linear member tied together on the outside of the An exhaust device for a blood pressure monitor, comprising: a needle valve communicating with the blood pressure monitor;