JPH04131207U - automatic exhaust valve - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a small automatic exhaust valve that can adjust the exhaust amount according to pressure changes inside a pressure chamber. [Structure] A movable cylinder slidably inserted into a case communicating with a pressure chamber, an elastic sheet adhered to the end face of the movable cylinder and provided with an air outlet hole in the center, and the movable cylinder. A needle is inserted into the body so as to be adjustable forward and backward, and is formed so that its sharp end can move in and out of the air outflow hole as the elastic sheet deforms, and the movable cylinder is always attached in a direction protruding from the case. and a closing means for keeping a space formed by the movable cylinder, the elastic sheet, and the case in a closed state, and the elastic sheet is deformed by a change in pressure inside the air pressure chamber. and adjusting the amount of exhaust air from the air outflow hole.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to an exhaust valve that exhausts air in a pressure chamber, and is used, for example, in a portable blood pressure monitor. related to automatic exhaust valves that are used in do.

0002

[Conventional technology]

Generally, a blood pressure monitor injects air into a cuff (pressure chamber) wrapped around the upper arm. While gradually expelling the air from the cuff through the pressure regulating valve, the systolic blood pressure and diastolic blood pressure are Measuring pressure. At this time, when measuring the diastolic blood pressure, the exhaust from the pressure regulating valve is not quantitative. Therefore, in the pressure region where diastolic blood pressure is measured, the pressure decreases slowly. Accurate measurement of diastolic blood pressure becomes difficult. In other words, the displacement from the pressure regulating valve is The higher the pressure inside the cuff, the more the volume is, and as the pressure inside the cuff decreases, the volume of displacement decreases and the pressure increases. The rate of decline will also be smaller.

0003 In order to solve such problems, the applicant of the present application has proposed In the publication, the amount of air discharged is automatically adjusted according to changes in the pressure inside the cuff, and the We proposed an automatic exhaust valve that can maintain a constant rate of decrease in cuff pressure. FIG. 5 shows the conventional automatic system proposed by the applicant in Utility Model Application Publication No. 63-186402. FIG. 3 is a vertical cross-sectional view of a dynamic exhaust valve.

0004 The automatic exhaust valve 17 is an upper opening of the main body case 10 formed in the middle of the pipe passage 11. A cylindrical support member 12 is hermetically fitted to the support member 10a, and a solid substance 18 is filled inside. The filled exhaust valve case 13 and the lower side edge of the cylinder body 13a of the exhaust valve case 13 The quick exhaust valve 15 disposed in the main body case 10 and the exhaust valve case 13 are always It consists of a spring 16 that biases in the direction of protrusion. The solid substance 18 disperses and absorbs pressure changes of pressurized air flowing in from the cuff. A fine air flow path is formed.

[0005] The air inside the cuff flows through the tube passage 11 and the through hole 13b bored in the barrel body 13a. The solid material 1 is guided into the exhaust valve case 13 to form a fine air flow path. 8 and is emitted into the atmosphere. In addition, during forced exhaust, the exhaust valve case 13 resists the biasing force of the spring 16. By pressing down the lower edge 12b of the cylindrical support member 12 and the quick exhaust valve. 15 is separated, and the air inside the cuff is transferred from the tube passage 11 to the inner wall surface of the cylindrical support member 12. It is instantly discharged to the outside through a gap 14 with the cylinder body 13a.

[0006]

[Problem that the idea aims to solve]

With recent advances in electronic technology, equipment has become lighter, smaller, shorter, and thinner, and the surroundings of automatic exhaust valves, etc. The same thing is required for peripheral equipment. For example, the blood pressure monitor mentioned above This is no exception, and due to the health boom in recent years, combinations of wristwatches and blood pressure monitors have become popular. There are also some proposals.

[0007] However, the conventional automatic exhaust valve described above uses a solid material that forms a fine air flow path. Because it has a structure that disperses and absorbs pressure changes in pressurized air, it is filled with solid materials. There was a problem in that the thickness of the exhaust valve case could not be kept below a certain thickness. In addition, conventional automatic exhaust valves are difficult to handle depending on the size and density of the solids filled in the exhaust valve case. Since the pressure drop characteristics of the pressure in the atmospheric pressure chamber are determined by When trying to convert to other equipment outside the company, please check the usage and purpose of the equipment. This had the disadvantage that the design of the automatic exhaust valve had to be changed.

[0008] This invention was created in view of the problems mentioned above, and its purpose is to Roha is an automatic exhaust valve that can adjust the exhaust volume according to changes in pressure within the pressure chamber. The overall thickness of the automatic exhaust valve can be reduced, and one automatic exhaust valve can be made thinner. We offer an automatic exhaust valve whose pressure drop characteristics can be set arbitrarily according to the purpose of use. It's there to serve.

[0009]

[Means to solve the problem]

The automatic exhaust valve of this invention has an exhaust volume that is proportional to the internal pressure of the pressure chamber and the hole area of the air outlet hole. For example, in order to solve the above problems, the A movable cylinder is slidably inserted into the case, and a movable cylinder is glued to the end face of the movable cylinder. An elastic sheet with an air outflow hole in the center and a movable cylinder that can be adjusted to move forward or backward. The pointed head moves in and out of the air outflow hole as the elastic sheet deforms. a needle formed so as to be able to move, and the movable cylinder always protruding from the case. an elastic body that biases in the direction of and a closing means for keeping the formed space in a closed state, and the pressure inside the pressure chamber is changed. The elastic sheet deforms due to the oxidation, and the amount of air discharged from the air outflow hole is adjusted. It is characterized by the following.

0010

[Effect]

Since the present invention is constructed as described above, the inside of the case communicating with the pressure chamber The elastic sheet deforms as the pressure changes, and as the elastic sheet deforms, the front The pointed head of the needle goes in and out of the air outlet hole of the elastic sheet and touches the hole surface of the air outlet hole. By changing the product, the air flow from the air outlet can be adjusted according to changes in the pressure inside the pressure chamber. Displacement volume can be adjusted. Furthermore, the needle can be adjusted forward and backward relative to the elastic sheet inside the movable cylinder. Since it is configured as follows, the exhaust amount from the exhaust valve can be arbitrarily set according to the pressure in the pressure chamber. This allows different pressure drop characteristics to be obtained with one automatic exhaust valve.

[0011]

【Example】

Embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 is a vertical sectional view of the automatic exhaust valve of the present invention, and Figure 2 is a front view of the automatic exhaust valve of the present invention. It is a partial cutaway view. 1 and 2, the automatic exhaust valve of the present invention has an air inlet hole 1a bored at the bottom. A lid 8 is screwed into the upper opening of the case 1, and the guide surface 8a of the lid 8 The movable cylinder 2 is inserted so that it can slide along the movable cylinder protruding from the case 1. A switch body 7 having an exhaust hole 7a in the center is screwed to one end of the body 2. . The movable cylinder body 2 is an elastic body provided between the lid body 8 and the switch body 7. 5, an elastic force is always applied in the direction of protrusion from the case 1.

0012 A flange portion 2a is formed on the other side of the movable cylinder 2, and a film formed to have a uniform thickness is formed on this flange portion 2a. The elastic sheet 3 is adhered. This elastic sheet 3 has some flexibility and stretch. It is made of compressible silicone rubber, etc., and has an air outflow hole 3a in its center. I'm being kicked. Further, a screw groove is formed inside the movable cylinder 2, and a screw is inserted into the outer circumferential surface of the screw groove. A needle 4 having a pointed tip 4a is screwed into the needle 4. The needle 4 and the elastic sheet 3 respond to changes in the pressure inside the case 1. With the deformation of the elastic sheet 3 toward the inside of the movable cylinder 2, the pointed head of the needle 4 4a must be arranged so that it can go in and out of the air outlet hole 3a. Further, a packing 6 is provided between the flange 2a of the movable cylinder 2 and the lid 8, and the flange 2a, the elastic sheet 3, and the inner surface of the case 1. to prevent leakage from the exhaust groove 9 to the outside of the case 1 through the gap between the inner surface of the case 1 and the It is prevented.

[0013] At least one exhaust groove 9 is provided on the inner surface of the guide surface 8a of the lid body 8. Ru. When performing forced exhaust, the switch body 7 is pressed against the elastic force of the elastic body 5. When it is lowered, the movable cylinder 2 is pushed down, and the packing as a closing means and the movable cylinder The flange 2a of the case 2 dissociates, and the air inside the pressure chamber (not shown) moves with the inner surface of the case 1. The gas is exhausted to the outside through the gap between the cylindrical body 2 and the flange 2a and the exhaust groove 9. Furthermore, on the external side of case 1, for example, a blood pressure measurement mechanism and a wristwatch are integrated. Attachment groove 1c for attaching to the wrist band of the blood pressure measuring device and the cuff A fixing groove 1d is formed on the bottom for fixing to a pressure chamber such as a cuff, etc. A guide groove 1e is formed in advance to reliably guide the air in the air pressure chamber to the air inflow hole 1a. It is.

[0014] 3(a) and 3(b) show the air outflow hole 3a of the elastic sheet 3 and the needle 4. Fig. 3 (a) is an explanatory diagram showing the relationship between the pointed head 4a and the case connected to the air pressure chamber. When the pressure inside case 1 is high, Figure 3 (b) shows that the pressure inside case 1, which is connected to the atmospheric pressure chamber, is low. This shows a case where In addition, in Figure 3 (a) and Figure 3 (b), the case where the pressure is high is Thick white arrows indicate low values, and thin arrows indicate low values. As shown in Figure 3 (a), the pressure inside the case 1, which is communicated with a pressure chamber (not shown), is When is high, the elastic sheet 3 is curved and deformed toward the needle 4 side, and the elastic sheet 3 The pointed head 4a of the needle 4 is largely inserted into the air outflow hole 3a. Case 1 The air inside is discharged from the air outlet hole 3a along the pointed head 4a in the direction of arrow A in the figure. , a small gap between the needle 4 and the screw part of the movable cylinder body 2 and the exhaust hole 7 of the switch body 7. It is discharged into the atmosphere through a. After that, the air in the pressure chamber flows through this air outlet hole 3a. If the pressure inside the case gradually decreases as more air is exhausted, the elastic sheet 3a will be deformed. The amount of insertion of the pointed head 4a into the air outflow hole 3a gradually recovers, and as shown in FIG. will also become smaller. In other words, the pressure inside case 1, which is connected to the pressure chamber, changes from high pressure to low pressure. When the elastic sheet 3 changes to The insertion amount of the point 4a of the needle 4 into the air outflow hole 3a changes, and the air outflow hole 3a changes. This is to adjust the displacement of the two.

[0015] Next, the position of the needle 4 in the movable cylinder 2 is adjusted so that the pressure in the atmospheric pressure chamber reaches 300. The relationship between pressure and the time it takes to fall from mmHg to atmospheric pressure was measured. In addition, when measuring , the elastic sheet 3 is made of silicone resin with a film thickness of 0.5 mm, and the diameter is 5 mm. The diameter of the air outflow hole 3a bored in the center was 1 mm. Also, the needle 4 has a diameter was 2 mm, the total length was 1.8 mm, and the tip angle of the pointed head was 60 degrees. In addition, inside the pressure chamber When the pressure reaches around 30mmHg (indicated by arrow B in the figure), press switch 7. Forced exhaust was performed to remove the air from the pressure chamber. The measurement results under the above conditions are plotted as a graph with the vertical axis representing the pressure in the air pressure chamber and the horizontal axis representing time. When written in the data graph, the position of the needle 4 in the movable cylinder 2 is Pressure drop curves as shown in FIGS. 4(a) and 4(b) were obtained. In Figure 4 (a), the pressure drop curve is almost linear from 300 mmHg to 50 mmHg. shows that the rate of decrease in pressure in the pressure chamber per unit time is almost constant. Ru. Also, the pressure drop curve in Figure 4 (b) is slightly lower than that in Figure 4 (a). The position is close to the elastic sheet 3, and as the pressure inside the air pressure chamber decreases, the pressure inside the air pressure chamber increases. This shows that the rate of pressure drop increases. In this way, the position of the needle 4 inside the movable cylinder 2 is advanced relative to the elastic sheet 3. The pressure drop characteristics within the atmospheric pressure chamber can be changed by finely adjusting the backward pressure.

[0016] The material and dimensions of each part of the elastic sheet 3 and the dimensions of each part of the needle 4 are as described above. The material and material are not limited to It goes without saying that the dimensions of each part should be determined. In addition, the air outflow hole 3a The air discharged from the needle 4 passes through the small gap between the threaded part of the movable cylinder 2 and is Although it is assumed that the exhaust gas is discharged into the atmosphere, it is not limited to this, and needle 4 or higher is used. Alternatively, the movable cylindrical body 2 may be provided with a ventilation hole for exhaust.

[0017]

[Effect of the idea]

As explained above, the automatic exhaust valve of the present invention responds to changes in pressure within the pressure chamber. The sheet deforms and the size of the air outlet hole is adjusted using the pointed head of the needle. The configuration is such that the exhaust volume is adjusted and the pressure drop characteristics within the pressure chamber are determined. The overall thickness of the automatic exhaust valve can be made extremely thin.

[0018] In addition, by adjusting the needle position forward and backward relative to the elastic sheet, the needle By changing the amount of insertion of the tip of the lever into the air outflow hole of the elastic sheet, The exhaust volume can be adjusted according to the internal pressure of the pressure chamber, and the pressure drop characteristics within the pressure chamber can be set arbitrarily. can be determined. In addition, by pressing down on the switch body, the air in the pressure chamber can be forced into the atmosphere. It can also be discharged. Therefore, the automatic exhaust valve of the present invention can be used, for example, in a portable wristwatch with a built-in blood pressure monitor. Not only can it be attached to blood pressure measuring devices, but it can also be attached to blood pressure monitors. It can be applied to a variety of devices.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an automatic exhaust valve of the present invention.

FIG. 2 is a partially cutaway front view of the automatic exhaust valve of the present invention.

FIG. 3 is an enlarged cross-sectional view of the main parts to explain the function of the automatic exhaust valve of the present invention, in which (a) shows a state in which the pressure in the air pressure chamber is high;
(b) indicates a state in which the pressure in the air pressure chamber is low.

[Figure 4] Measurement results of the automatic exhaust valve of the present invention, (a) is the pressure drop rate in the pressure chamber adjusted to a constant state per unit time, and (b) is the pressure drop as the pressure in the pressure chamber decreases. The rate has been adjusted to increase.

FIG. 5 is a longitudinal sectional view of a conventional automatic exhaust valve.

[Explanation of symbols]

1 Case 1a Air inflow hole 2 Movable cylinder body 3 Elastic sheet 3a Air outflow hole 4 Needle 4a Pointed head 5 Elastic body 6 Packing (closing means) 7 Switch body 8 Lid body 8a Guide surface 9 Exhaust groove

Claims (1)

[Scope of utility model registration request] 1. A movable cylinder slidably inserted into a case communicating with an air pressure chamber; an elastic sheet adhered to an end surface of the movable cylinder and having an air outflow hole in the center; a needle inserted into the movable cylinder so as to be adjustable forward and backward, and formed such that its sharp end can move in and out of the air outflow hole as the elastic sheet deforms; and a direction in which the movable cylinder always projects from the case. and a closing means for keeping a space formed by the movable cylindrical body, the elastic sheet, and the case in a closed state. An automatic exhaust valve characterized in that the automatic exhaust valve is deformed to adjust the amount of exhaust from the air outflow hole.