JPH09135817A - Flow control valve and automatic sphygmomanometer equipped with the flow control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow control valve having an excellent close contact characteristic, allowing the easy adjustment of a flowrate across the valve and ensuring freedom from an unnecessary leakage from the valve even in the valve close contact condition where the dispersion of flowrate characteristics is small. SOLUTION: A joint 7 is turned for a body 140 having a pressure fluid outlet 18 for externally releasing the pressurized air via an air chamber, so as to axially move a valve part and change a load on a spring plate 110, thus enabling a flow rate to be adjusted after the completion of the assembly of a valve. In other words, a pin 13 pressed into a frame 6 is inserted into the hole of the joint 7, and when the frame 6 is turned with the body 140 kept in a fixed state, the joint 7 is concurrently turned. As a result, the condition of the joint 7 screwed to the body 140 changes, and the body 140 can be moved axially. According to this construction, a load on the spring plate 110 can be changed and flowrate adjustment can be made.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow rate control valve and an automatic sphygmomanometer including the flow rate control valve. For example, a flow rate control valve capable of controlling a flow rate characteristic in the valve in an assembled state and an automatic blood pressure control valve including the flow rate control valve. It relates to a blood pressure monitor.

[0002]

2. Description of the Related Art Conventionally, various solenoid valves have been proposed which open and close a valve by passing a current through a coil. An example of the conventional solenoid valve is shown in FIG.

As shown in FIG. 5, the conventional solenoid valve is a solenoid part for controlling the opening and closing of the valve. As a solenoid part, a frame 6, a plunger 10 of a valve body part are slid up and down in the drawing, a coil 3, a coil 3 and a valve. The magnet support 5 for positioning and holding the tube 4 of the body at a predetermined position, the coil 3 and the O-ring
It is composed of a plate 2, which is held together with the magnet support 5 via an O-ring 9, and a pin 13 for connecting the solenoid portion to the valve body portion. The pin 13 is press-fitted into the hole 6a provided in the lower portion of the frame 6,
The plate 2 is crimped by the frame 6 and integrated.

The valve body portion includes a body 14, a flexible spring plate 11, a tube 4, a core 8 positioned and held by the tube 4, a core 8 in the tube 4 and a pressure in response to a magnetic force from the coil 3. It is composed of a plunger 10 and a valve seat 15 which are made of an attracting material that slides vertically between the upper end portion of the outflow passage 18. And core 8
The joint 7 is caulked with the tube 4, and the valve seat 15 is adhered to the plunger 10.

The pressure of the pressurized gas is the pressure outlet 1
8 from the lower end of the air chamber 8
0 is connected to the outside air.

In the solenoid portion and the valve body portion having the above-mentioned structure, after the pin 13 is pressed into the hole of the body 14, the C ring 1
It is assembled and fixed by fixing with.

The operation of the conventional solenoid valve having the above structure will be described below.

In the initial state of operation (coil current = 0), the elastic force of the spring plate 11 causes the valve seat 15 to move.
Are pressed against the body 14 and are configured so that the pressurized gas does not flow out of the pressure outflow passage 18 through the air chamber 20 to the outside (to prevent air leakage).

When an electric current is applied to the coil 3, a magnetic force is generated from the coil 3, the plunger 10 is attracted to the core 8 and slides in the tube 4 in the upper direction of the drawing. As a result, a gap is formed between the valve seat 15 and the upper end portion of the pressure outflow passage 18 of the body 14, and the pressurized gas flows out through the pressure outflow passage 18 to the outside.

The relationship between the coil current and the flow rate at this time is uniquely determined, and as the coil current increases, the flow rate also increases.

The flow rate is adjusted by inserting an adjusting thin plate having an appropriate thickness between the frame 6 and the joint 7 and then assembling, and the elastic force of the spring plate 11 is adjusted by the inserting amount of the adjusting thin plate. Was done by changing.

[0012]

However, the conventional solenoid valve is apt to have a flow rate characteristic deviation during assembly, and as a result, stable flow rate characteristics cannot be obtained. Therefore, in order to suppress the variation in the flow rate characteristic within a certain range, it is necessary to repeat the steps of (adjustment of the valve element (insertion of a thin plate for adjustment) → assembly of the solenoid → measurement of the flow rate characteristic).

Further, to prevent air leakage, measures have been taken such as making the shape of the valve seat complicated, or adjusting and adjusting at the time of assembly, if necessary.

Since the conventional flow control valve has a large variation in flow characteristics, stable decompression characteristics can be obtained in a wide range of cuff size from neonatal to obese, especially when this valve is used in an automatic blood pressure monitor. I couldn't get it. Further, if there is air leakage, there is a problem that stable control is difficult, especially with a newborn cuff.

[0015]

The present invention has been made for the purpose of solving the above-mentioned conventional problems, and is provided with, for example, the following structure as one means for achieving such an object.

That is, a body member having a pressure outlet for releasing pressurized gas to the outside through an air chamber, and a valve seat for closing or opening the pressure outlet are provided at the tip. A plunger, a plunger driving means for moving a valve seat at the tip of the plunger to a valve closing position or a valve opening position of the pressure outlet, and the body member for pressing the plunger in a direction of the pressure outlet with a predetermined elastic force. A plunger pressure contact member that is locked to the plunger, and an adjusting unit that adjusts the pressure contact force of the plunger pressure contact member with respect to the plunger to adjust the gas flow rate of the pressure outlet, and the adjusting unit includes the body member and It is characterized in that the gas flow rate at the pressure outlet can be adjusted after the plunger, the plunger driving means, and the adjusting means are integrally assembled.

Further, for example, the valve seat is biased toward the pressure outlet with a predetermined pressure by a spring member arranged in the plunger, and the valve seat is opened when the pressure outlet of the plunger is closed. It is characterized in that it is configured to be in pressure contact with the pressure outlet direction. Alternatively, the plunger driving means includes an electromagnetic coil that is biased when the pressure outlet is opened to slide the plunger in a direction away from the pressure outlet.

Further, for example, the adjusting means includes a male screw member locked to the plunger driving means and a female screw portion provided on the body member so as to be screwed with the male screw member, and at least The flow rate is adjusted by rotating the female screw member with the body member fixed to change the screwing state to adjust the plunger pressure contact force of the plunger pressure contact member.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. The solenoid valve of this example is most suitable for a gas pressure reducing solenoid valve used in a flow control valve, an automatic blood pressure monitor, etc., and has a configuration that allows the flow rate passing through the valve to be easily controlled after the valve is assembled. ing.
Therefore, for example, by using the solenoid valve of this example in an automatic blood pressure monitor, it is possible to reduce the pressure in the cuff at a constant pressure reduction rate.

An example of an embodiment of the present invention will be described below in detail with reference to FIGS. 1 and 2. FIG. 1 is a schematic cross-sectional view showing the configuration of the solenoid valve of the present example in the closed state, and FIG. 2 is a schematic cross-sectional view showing the configuration of the solenoid valve of the present example in the valve open state.

An embodiment of the present invention will be described with reference to the schematic sectional views of FIGS.

In FIGS. 1 and 2, the same components as those in FIG. 5 described above are designated by the same reference numerals. The solenoid portion may have a configuration substantially similar to the configuration of FIG. 5 described above, and is configured by the frame 6, the plate 2, the coil 3, the magnet support 5, the O-ring 9, and the pin 13, and the pin 13 of the frame 6. The plate 2 is press-fitted into the hole, and the plate 2 is caulked by the frame 6 and integrated.

The valve body portion of this embodiment includes a tube 4, a joint 7, a core 8, an O-ring 12 having a substantially circular cross section, a valve seat 15,
Spring 16, valve seat restraining member 17, valve seat pressing member 1
9, a plunger 100, a spring plate 110, and a body 140. The plunger 100, the spring plate 110, and the body 140 are different from the plunger 10, the spring plate 11, and the body 14 shown in FIG. 5, and additionally, the joint 7, the O-ring 12 having a substantially circular cross section, the spring 16, and the valve seat restraint. This is a configuration including a member 17 and a valve seat pressing member 19. The core 8 and the joint 7 of this example are caulked by the tube 4 and integrated.

The structure of the body 140 is also different, and the illustrated upper opening portion of the body 140 has a female screw structure which is screwed into a screw thread arranged on the outer peripheral portion of the joint 7 and is different from the body 140. The joint 7 and the joint 7 are screwed into each other, and the joint 7 is screwed into the body portion 140 to be integrally fixed.

At the tip of the joint 7, a circular plate-shaped O-ring for positioning and holding the O-ring 12 is provided.
A ring holding portion 7a is provided, and the joint 7 and the body 140 are screwed together so that the O-ring 12 is located between the O-ring holding portion 7a and the body 140. O
The ring 12 is incorporated to eliminate the backlash of this screw structure.

Further, the plunger 100 is provided with a hole for inserting the spring 16 in a lower portion holding the valve seat 15, and a large diameter is provided in the vicinity of the opening of the hole so that the valve seat 15 can be loosely fitted. Has become. Then, the spring 16, the valve seat pressing member 19 having the upper end convex portion fitted in the spring 16 and the valve seat 15 are sequentially inserted into the lower opening of the plunger 100, and fixed by the valve seat restraining member 17 so as not to fall off. To do. Therefore, the valve seat 15 is urged from the inside of the plunger 100 by the elastic force of the spring 16 through the valve seat pressing member 19 in the direction of the valve seat restraining member 17 and is pressed against it.

Also in this embodiment, when the valve is closed, the spring plate 110 keeps the valve seat 15 in pressure contact with the upper end of the pressure outlet passage 18. At this time, when the elastic force of the spring plate 110 is stronger than the elastic force of the spring 16, the valve seat 15 is pushed into the plunger 100 and the valve seat 15
Is maintained in a state in which it is pressed against a predetermined pressure by the elastic force of the spring 16. Moreover, the valve seat 15 is evenly kept pressed against the upper end of the pressure outlet passage 18 by the action of the spring 16, so that a valve structure in which gas is less accidentally outflowed into the air chamber (less air leakage) can be provided. .

In the case of adjusting the flow rate in this example having the above structure, the joint 7 is rotated with respect to the body 140 and the valve body portion is moved in the axial direction to change the load of the spring plate 110. By. That is, in this example, the pin 13 press-fitted into the frame 6
Is inserted into the hole of the joint 7, and when the frame 6 is rotated with the body 140 fixed, the joint 7 is rotated in conjunction, so the screwed state of the joint 7 and the body 140 changes, and the joint 7 is It is possible to move in the axial direction. As a result, the spring plate 1
The load of 10 can be changed, and the flow rate can be adjusted.

The C ring 1 is for fixing the solenoid portion and the valve body portion, and after the flow rate is adjusted, the C ring 1 is fitted and assembled.

The operation of this example having the above configuration will be described below.

The operation is as shown in FIG. 1 in the initial state (coil current = 0), and the plunger 100 is pressed against the body 140 by the elastic force of the spring plate 110. As a result, the valve seat 15 is closed by the elastic force of the spring 16 against the upper end of the pressure outflow passage 18 of the body 140, and the pressure outflow passage 18 is closed, so that the pressurized gas does not leak from the air chamber 200 to the outside ( It does not leak air).

In this state, when a current is passed through the coil 3, a magnetic force is generated and the plunger 100 is attracted to the core 8 and slides in the tube 4 upward in the figure. As a result, as shown in FIG. 2, a gap is formed between the valve seat 15 and the pressure outflow passage 18 portion of the body 140, and the pressurized gas is pressurized.
Flows through to the outside.

The relationship between the coil current and the flow rate at this time is a characteristic that the flow rate increases as the coil current increases as shown by the characteristic A in FIG. 3 when the pressure is constant. It is extremely easy to obtain the characteristic shown in characteristic B.

Further, in this example, since the elastic force of the spring 16 is used for preventing air leakage, instead of using the force of the spring plate 110, the coil current is smaller than that of the conventional structure shown in FIG. Can be few.

As described above, according to this example, even after the temporary assembly of the solenoid valve (the final state before the solenoid portion and the valve body portion are fixed by the C ring 1), the frame 6 is simply rotated. Thus, the joint 7 can be rotated in an interlocking manner, and the joint 7 can be moved in the axial direction. Thereby, the load of the spring plate 110 can be changed, and the flow rate can be easily adjusted.

As a result, for example, by using the flow rate control valve of this example in an automatic blood pressure monitor, the flow rate can be easily adjusted, and stable depressurization characteristics can be obtained in a wide range of cuff sizes for neonates and obese persons. Further, the valve seat 15 can be uniformly pressed into contact with the pressure outflow passage 18 by the spring 16, and it is possible to provide an air leak-free, particularly stable control for a newborn cuff.

In the above description, the case where the pressurized gas is made to flow to the outside through the pressure chamber 18 and the air chamber 200 is explained. However, the present invention is not limited to the above example, and any material can be used as the material for controlling the flow rate. For example, a liquid containing water can be applied without changing the structure shown in the drawing, and by changing the shape of the pressure outflow passage 18, it can be used as a control valve for all materials having different viscosities.

Next, a case where the flow rate control valve according to the present embodiment described above is applied to an automatic blood pressure monitor will be described below with reference to FIG. FIG. 4 is a diagram showing a configuration of an automatic blood pressure monitor using a solenoid valve capable of controlling the flow rate of this example.

In FIG. 4, 211 is a pressurizing pump for sending air to the cuff 230 to pressurize the measurement site of the living body, 212 is a quick exhaust valve for abruptly reducing the pressure inside the cuff 230, and 213 is an adder. It is a constant exhaust valve for reducing the cuff pressure by exhausting a fixed amount in order to measure the blood pressure value after pressure, and the above two valves, especially the constant exhaust valve 213, is best to use the flow control valve of this example. If it is a constant exhaust valve, the flow rate is adjusted in the assembled state, and it is, for example, 2 to 3 mm.
It is possible to evacuate and depressurize at Hg / sec.

Reference numeral 214 is a pressure sensor, which is a cuff 2.
The electrical parameter changes according to the pressure in 30. 2
Reference numeral 16 is an air path (air chamber) that connects these respective parts, and is provided with a cuff 230 via an air connector 221.
Connected to. A pressure detection amplifier 223 detects an electric parameter of the pressure sensor 214 which changes according to a change in the cuff pressure, converts the electric parameter into a corresponding electric signal, amplifies and outputs the electric signal.
Reference numeral 224 is a microphone amplifier that detects and amplifies a change in an electric signal from a microphone 222 positioned at an upper position of a blood pressure measuring blood vessel in the cuff 230. The output of the pressure detection amplifier 223 and the microphone amplifier 224 is A /
It is output to the D conversion unit 257, converted into a corresponding digital signal here, and read by the CPU 251.

In the above description, an example in which the blood pressure is measured by detecting, for example, Korotkoff sound (K sound) or pulse sound by the microphone provided in the cuff 230, the present invention is limited to the above example. Instead, the blood pressure may be measured by utilizing the fact that the pressure of the cuff 230 changes due to pulsation or the like and detecting the pressure change due to this pulsation or the like by the pressure sensor 214. . Further, a configuration may be adopted in which pulsating, for example, arterial blood flow is irradiated with light by an LED or the like, and reflected light of light due to arterial blood flow is detected by a phototransistor or the like, thereby detecting a change in intravascular capacity and measuring blood pressure. Good. Any method can be used as the blood pressure measuring method according to the present invention, and the method is not limited to that method.

Further, 251 is a CPU for one-chip calculation and control, 252 is a ROM in which operation programs of the CPU 251 and various parameters for blood pressure measurement are stored, and 253 is a measurement result or measurement progress. The RAM 254 stores a buzzer that outputs various notification sounds associated with blood pressure measurement and the like, and the display 255 (LCD) that can display measurement results, measurement guidance, and the like.

Further, 258 is an operation unit for inputting various instructions such as blood pressure measurement instruction, and 259 is a control of the CPU 251 to drive and control the sphygmomanometer mechanism (pressurizing pump 211, quick exhaust valve 212, constant exhaust valve 213). It is a sphygmomanometer mechanism control unit.
In addition to this, a printer may be further provided so that the measurement result can be printed out. In this case, a general commercially available printer may be connected and output.

In the above configuration, the CPU 251 controls the sphygmomanometer mechanism when the wearing of the cuff 230 on the subject is completed, the blood pressure measurement preparation is completed, and a measurement start instruction or the like is input from the operation unit 258. Exhaust from the exhaust valves 212 and 213 is stopped in the portion 259, the pressurizing pump 211 is started, air is sent to the cuff 230, and the cuff pressure is increased. Then, after that, the exhaust valves 212 and 213 are controlled by a known method, and the blood pressure is measured using the detection signals from the pressure sensor 214 and the microphone.

[0045]

As described above, according to the present invention, it becomes possible to easily adjust the flow rate of the valve, and it is possible to provide a solenoid valve having a small variation in flow rate characteristics. Further, it is possible to provide a flow rate control valve having excellent valve closing characteristics without unnecessary leakage from the valve even when the valve is closed.

[0046]

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a valve closed state of an example of an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a valve open state of the present example shown in FIG.

FIG. 3 is a diagram showing a flow rate characteristic of a solenoid valve.

FIG. 4 is a diagram showing a configuration of an automatic sphygmomanometer using a solenoid valve capable of controlling the flow rate of the present example.

FIG. 5 is a diagram showing a configuration of a conventional solenoid valve.

[Explanation of symbols]

 1 C ring, 2 plate 3 coil 4 tube 5 magnet support 6 frame 7 joint 8 core 9 O-ring 10, 100 plunger 11, 110 spring plate 12 O-ring 13 pin 14, 140 body 15 valve seat 16 spring 17 valve seat Suppression member 19 Valve seat pressing member

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshimi Seshita 2-3-3 Shiba-koen, Minato-ku, Tokyo Inside Walbro Japan Co., Ltd. (72) Inventor Hitoshi Fujisawa 2-3-3, Shiba-koen, Minato-ku, Tokyo No. 3 Inside Walbro Japan

Claims (5)

[Claims] 1. A body member having a pressure outlet for releasing gas in an air chamber to the outside, and a plunger having a valve seat at a tip end thereof for closing or opening the pressure outlet. A plunger driving means for moving a valve seat at a tip portion of the plunger to a valve closing position or a valve opening position of the pressure outlet; and a body member for pressing the plunger with a predetermined elastic force in the pressure outlet direction. A plunger pressing member that is stopped; and an adjusting unit that adjusts a pressing force of the plunger pressing member against the plunger to adjust a gas flow rate of the pressure outlet, the adjusting unit including the body member and the plunger. A flow control valve capable of adjusting the gas flow rate at the pressure outlet after the plunger drive means and the adjusting means have been integrated together. 2. The valve seat is biased toward the pressure outlet with a predetermined pressure by a spring member arranged in the plunger, and the valve seat is opened when the pressure outlet of the plunger is closed. The flow control valve according to claim 1, wherein the flow control valve is configured so as to be in pressure contact with the pressure outlet. 3. The plunger drive means includes an electromagnetic coil that is urged when the pressure outlet is opened to slide the plunger in a direction away from the pressure outlet. The flow control valve according to claim 1 or 2. 4. The adjusting means includes a male screw member locked to the plunger driving means and a female screw portion provided on the body member so as to be screwed with the male screw member, and at least the body. 2. The flow rate is adjusted by rotating the female screw member with the member fixed to change the screwing state to adjust the plunger pressure contact force of the plunger pressure contact member. 4. The flow control valve according to any one of 3 to 3. 5. An automatic blood pressure monitor comprising the flow control valve according to any one of claims 1 to 4.