WO2019159639A1

WO2019159639A1 - Electronic valve, sphygmomanometer, blood pressure measuring method, and apparatus

Info

Publication number: WO2019159639A1
Application number: PCT/JP2019/002302
Authority: WO
Inventors: 佐野　佳彦; 西岡　孝哲
Original assignee: オムロンヘルスケア株式会社
Priority date: 2018-02-13
Filing date: 2019-01-24
Publication date: 2019-08-22
Also published as: JP2019136351A

Abstract

This electronic valve is provided with a yoke (3), a pole piece (4), a solenoid coil (7), and a diaphragm (6). The pole piece (4) has a first fluid input/output port (11) communicating with an opening (4o). A biasing part (5) biases the diaphragm (6) away from one end section (4e) of the pole piece (4). When not in operation, the electronic valve becomes an open state in which an opening (4o) is open. During operation, the electronic valve can become a closed state in which the diaphragm (6) approaches the one end section (4e) of the pole piece (4) due to the magnetic force of the solenoid coil (7) such that the opening (4o) is blocked. The diaphragm (6) extends in a spatially continuous manner from the center toward the edge so as to cover the entire periphery of the peripheral end surface (4e1) of the pole piece (4), or the entire periphery of an annular edge (3e) of the yoke (3). In the closed state, the inner surface (6b) of the diaphragm (6) is in close contact with the peripheral end surface (4e1) of the pole piece (4) or with the annular edge (3e) of the yoke (3).

Description

Electromagnetic valve, sphygmomanometer, blood pressure measurement method, and device

The present invention relates to a solenoid valve, and more particularly to a solenoid valve that opens and closes by the magnetic force of a solenoid coil. The present invention also relates to a sphygmomanometer including such an electromagnetic valve, and a blood pressure measurement method for measuring blood pressure by adjusting the cuff pressure by opening and closing such an electromagnetic valve. Moreover, this invention relates to the apparatus provided with such an electromagnetic valve.

Conventionally, as an electromagnetic valve used in a sphygmomanometer, for example, one disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 08-203730) is known. The electromagnetic valve includes a U-shaped frame and a yoke attached so as to close the open end of the frame. A substantially cylindrical coil bobbin (coil frame) and a solenoid coil wound around the coil bobbin are accommodated therein. Further, a rod-shaped movable iron core is slidably inserted in the coil bobbin. On the bottom plate of the frame facing the yoke, a fixed iron core provided with a flow port through which fluid flows is disposed. One end of the movable iron core is opposed to the distribution port of the fixed iron core. When the solenoid coil is in a non-energized state, one end of the movable iron core is separated from the flow port of the fixed iron core by the biasing force of the spring. During operation in which the solenoid coil is energized, the movable iron core is moved in the coil bobbin against the urging force of the spring by the magnetic force generated by the solenoid coil, and one end of the movable iron core is connected to the fixed iron core. Close the distribution port. Thereby, the solenoid valve is opened and closed.

Japanese Patent Application Laid-Open No. 08-203730

By the way, from the recent health-oriented boom, there is an increasing need to perform blood pressure measurement with a blood pressure monitor always worn on the wrist like a wristwatch. In that case, it is desired to reduce the size of a component such as a solenoid valve as much as possible.

However, in a general electromagnetic valve as disclosed in Patent Document 1, there is a problem that the size of the electromagnetic valve is increased because the movable iron core is rod-shaped and moves along its longitudinal direction. In addition, since the blood pressure monitor of the type attached to such a wrist is often driven by a battery, it is necessary to save power of the electromagnetic valve.

Therefore, an object of the present invention is to provide a solenoid valve that can be configured in a small size and can save power. Another object of the present invention is to provide a sphygmomanometer equipped with such an electromagnetic valve, and a blood pressure measuring method for measuring blood pressure by opening and closing such an electromagnetic valve. Moreover, the subject of this invention is providing the apparatus provided with such an electromagnetic valve.

In order to solve the above problem, the electromagnetic valve of this disclosure is:
A solenoid valve that allows or blocks fluid flow,
A yoke including an end plate portion having an annular periphery, and a side plate portion connected to the periphery of the end plate portion and surrounding the space adjacent to one side of the end plate portion in an annular shape;
A pole piece extending in one direction from one end existing in the space on one side to the other end on the opposite side, perpendicular to the end plate portion of the yoke, and the pole piece is open to the one end A first fluid inlet / outlet communicating with the opening through the pole piece at the other end,
A solenoid coil housed in an annular space between the pole piece and the side plate of the yoke;
A diaphragm made of a plate-like magnetic material facing the end plate portion of the yoke through the space and having a dimension extending over the annular edge of the side plate portion of the yoke;
A biasing portion that biases the diaphragm in a direction to move away from the one end of the pole piece in a manner to move the diaphragm in parallel in the one direction,
During non-operation when the solenoid coil is in a non-energized state, the diaphragm is separated from the one end of the pole piece by the urging force of the urging unit, and the opening is opened.
During operation in which the solenoid coil is energized, the diaphragm approaches the one end of the pole piece against the urging force of the urging portion by the magnetic force generated by the solenoid coil, and the opening is closed. Closed state,
The diaphragm covers the entire circumference of the peripheral end surface around the opening or the entire circumference of the annular edge of the side plate portion of the yoke from the center toward the peripheral edge. In the closed state, the inner surface on the side facing the end plate portion of the diaphragm is the peripheral end surface around the opening of the one end of the pole piece, or in the closed state, or The yoke is configured to be in close contact with the annular edge of the side plate portion.

In the present specification, “yoke” and “pole piece” are elements that serve to guide lines of magnetic force well known in the field of electromagnets, and are each made of a magnetic material (in particular, a ferromagnetic material such as iron is preferable).

The shape of the periphery of the end plate portion of the yoke widely includes an annular shape such as a circle and a rounded square (a square with rounded corners). The same applies to the annular shape of the side plate.

The “annular edge” of the side plate portion of the yoke refers to the edge opposite to the end plate portion.

The “other end portion” of the pole piece may protrude from the end plate portion of the yoke, or the outer surface of the end plate portion (the space on one side of the two surfaces of the end plate portion is It may stop on the surface facing the other side.

As the open / close state of the valve, there is an intermediate state in which the flow rate is controlled according to the energization amount of the solenoid between the closed state and the open state.

“In close contact” means that the fluid is in close contact with the fluid. For example, if the fluid is a gas, it means that it is in airtight contact. In addition, if the fluid is a liquid, it means that it is in liquid-tight contact.

In the electromagnetic valve according to the present disclosure, when the solenoid coil is in a non-energized state, the diaphragm is separated from the one end portion of the pole piece by the biasing force of the biasing portion, and the opening is opened. It becomes a state. When in this open state, fluid flow through the pole piece is allowed. This solenoid valve is a normally open valve.

During operation in which the solenoid coil is energized, the diaphragm approaches the one end of the pole piece against the urging force of the urging portion by the magnetic force generated by the solenoid coil, and the opening is closed. Can be closed. Specifically, when the solenoid coil is in an energized state (during operation), the lines of magnetic force generated by the solenoid coil reach, for example, the peripheral edge of the end plate portion through the side plate portion of the yoke, and the end plate portion From the peripheral edge of the pole piece through the end plate portion to the orthogonal part of the pole piece, from the orthogonal part through the pole piece to the one end of the pole piece, from the one end to the one end and the It circulates in a path (magnetic circuit) that reaches an approaching point with the diaphragm and further reaches the annular edge of the side plate portion of the yoke through the diaphragm. If the direction of energization to the solenoid coil is reversed, the lines of magnetic force generated by the solenoid coil circulate in this direction in the reverse direction. As a result, the solenoid coil generates a magnetic force against the urging force of the urging unit with respect to the diaphragm. Due to this magnetic force, the diaphragm can approach the one end of the pole piece, and the opening can be closed. When in the closed state, the fluid flow through the pole piece is blocked. Thus, in this solenoid valve, the solenoid coil is in an open state or a closed state depending on whether the solenoid coil is in a non-energized state (when not operating) or the solenoid coil is in a conductive state (when operating). Can do. Thereby, the flow of the fluid through the pole piece (that is, the electromagnetic valve) can be allowed or blocked.

Here, in this solenoid valve, in order to allow or block the flow of fluid, the plate-like diaphragm approaches or separates from the one end of the pole piece in a posture facing the end plate of the yoke. It is configured to move in parallel in one direction. That is, unlike the conventional example (the movable iron core is rod-shaped and moves along its longitudinal direction), in this solenoid valve, the plate-shaped diaphragm moves in one direction perpendicular to the plate surface of the diaphragm. To do. Therefore, the size of the solenoid valve can be reduced with respect to the one direction in which the diaphragm moves. As a result, the electromagnetic valve can be made compact.

Further, in this electromagnetic valve, the diaphragm is configured such that the diaphragm is formed from the center toward the peripheral edge, the entire circumference of the peripheral end surface around the opening among the one end portions of the pole piece, or the annular edge of the side plate portion of the yoke. It extends continuously spatially so as to cover the entire circumference of the. Further, in the closed state, the inner surface of the diaphragm (the surface on the side facing the end plate portion of the yoke) is the peripheral end surface around the opening of the one end portion of the pole piece, or the yoke. Close to the annular edge of the side plate portion. Here, the area of the region surrounded by the peripheral end face of the one end of the pole piece (referred to as Sa) or the area of the yoke as compared to the area of the opening (referred to as S0). The area (referred to as Sb) of the region surrounded by the annular edge of the side plate portion is large. That is, S0 <Sa <Sb. Therefore, for example, the pressure of the fluid applied to the opening from the first fluid inlet / outlet side (this is referred to as an opening side pressure P1) and the rear surface of the diaphragm (the side opposite to the end plate portion of the yoke) are directed. It is assumed that the pressure of the fluid applied to the surface (this is the back side pressure P0) is the same positive pressure (exceeds atmospheric pressure). In this case, the former relationship between the pressing force by the opening side pressure P1 (referred to as F1) and the pressing force by the back side pressure P0 (referred to as Fa for the area Sa and Fb for the area Sb) is as follows. The latter Fa and Fb are larger than F1. That is, since F1 = P1 × S0, Fa = P0 × Sa, and Fb = P0 × Sb, for example, if 0 <P1≈P0, F1 <Fa <Fb. If the back side pressure P0 is larger than the opening side pressure P1 (that is, if 0 <P1 <P0), then F1 << Fa << Fb.

As a result, in this solenoid valve, once the open state is changed to the closed state, if the back side pressure P0 is equal to or higher than the opening side pressure P1 (both are positive pressures), the closed state is maintained. The magnetic force that should be generated by the solenoid coil can be reduced against the urging force of the urging unit. That is, the closed state is assisted. Therefore, in this solenoid valve, a small amount of current is supplied to the solenoid coil, and power saving can be achieved.

The solenoid valve according to one embodiment is characterized in that the pole piece and the yoke are integrally formed.

In the solenoid valve according to this embodiment, the pole piece and the yoke are integrally formed. Therefore, the magnetic resistance between the pole piece and the yoke is small, and the efficiency of the magnetic circuit using them as a path is increased. . In addition, the airtightness between the pole piece and the yoke can be improved to prevent air leakage.

In one embodiment of the electromagnetic valve, the magnetic material forming the diaphragm is permalloy.

Here, “permalloy” refers to an Ni—Fe alloy.

In the electromagnetic valve according to this embodiment, the diaphragm is plate-shaped and made of permalloy, and thus can be configured to be lighter than, for example, a rod-shaped movable iron core. In that case, when the posture (orientation) of the electromagnetic valve changes variously with respect to the vertical direction, the characteristic (for example, the current-flow-current characteristic) is hardly affected by the posture of the electromagnetic valve.

If the element driven to open and close the valve is a rod-shaped movable iron core, it has a relatively large weight, so when the posture (orientation) of the solenoid valve changes with respect to the vertical direction, Along with this, the gravitational component that the movable iron core receives along the sliding direction changes greatly, and the characteristics of the solenoid valve are greatly affected.

In one embodiment of the electromagnetic valve, an elastic body for closing the opening is integrally attached to a portion of the diaphragm facing the opening at the one end of the pole piece.

In this specification, “elastic body” refers to an object made of an elastic material (flexible material) such as silicone rubber, nitrile rubber (NBR), ethylene propylene diene rubber (EPDM).

In the electromagnetic valve according to this embodiment, when the transition from the open state to the closed state is performed, the elastic body of the diaphragm approaches the opening at the one end of the pole piece. Thereby, a stable energization current (or drive voltage) versus flow rate characteristic can be obtained. In the closed state, the elastic body of the diaphragm reliably blocks the opening at the one end of the pole piece.

Note that the elastic body is preferably attached to the diaphragm by press-fitting, bonding, or insert molding. Thereby, the elastic body can be easily and integrally attached to the diaphragm.

In one embodiment of the electromagnetic valve, the pole piece has a recess opened toward the elastic body attached to the diaphragm at the one end, and the opening is opened at the bottom of the recess. Features.

In the electromagnetic valve according to this embodiment, when in the closed state, the elastic body attached to the diaphragm closes the opening while being accommodated in the recess at the one end of the pole piece. Therefore, the elastic body can block the opening stably.

In the solenoid valve of one embodiment,
With the other end of the pole piece exposed to the outside, the yoke, a portion of the pole piece that extends into the space on the one side, the solenoid coil, the diaphragm, and the biasing portion, With a hermetically sealed case that fluidly and collectively covers
A second fluid inlet / outlet is provided through the outer wall of the sealed case.

The solenoid valve of this embodiment is suitable for being inserted into a flow path and allowing or blocking the flow of fluid through the flow path. If the electromagnetic valve is in an open state, for example, the first fluid is passed through the opening at the one end of the pole piece from the second fluid inlet / outlet (the diaphragm is open from the one end). The fluid can flow through the solenoid valve toward or away from the fluid inlet / outlet. If the solenoid valve is in a closed state, the opening (the diaphragm is close to the one end portion and is in a closed state) is blocked, so that the second fluid inlet / outlet and the first fluid passage through the solenoid valve are blocked. There is no fluid flow between the fluid ports.

In one embodiment of the electromagnetic valve, the sealing case is along a first end wall along the outer surface of the end plate portion of the yoke and a back surface facing the opposite side of the end plate portion of the diaphragm. It includes a second end wall, and an annular outer peripheral wall connecting the peripheral edge of the first end wall and the peripheral edge of the second end wall.

The “outer surface” of the end plate portion refers to a surface facing the opposite side to the space on one side of the two spreading surfaces of the end plate portion. The “rear surface” of the diaphragm refers to a surface of the two surfaces of the diaphragm that faces away from the end plate portion of the yoke.

In the solenoid valve according to this embodiment, the size of the sealed case from the first end wall to the second end wall is set small, so that the flatness along the first and second end walls is flat. Can have an outer shape. Such an outer shape is suitable for mounting the electromagnetic valve (sealing case) along, for example, a wiring board and forming the electromagnetic valve (sealing case) and the wiring board together in a flat shape as a whole.

In the electromagnetic valve according to one embodiment, the other end portion of the pole piece provided with the first fluid inlet / outlet is disposed to protrude outward from the first end wall of the sealed case. And

In the electromagnetic valve according to this embodiment, the flow path is easily connected to the first fluid inlet / outlet so that fluid can flow therethrough.

In the solenoid valve according to one embodiment, the second fluid inlet / outlet port is disposed to protrude outward from the first end wall, the second end wall, or the outer peripheral wall of the sealed case. Features.

In the solenoid valve according to this embodiment, the flow path is easily connected to the second fluid inlet / outlet so that fluid can flow therethrough. In particular, when the second fluid inlet / outlet is arranged to protrude outward from the outer peripheral wall of the sealed case, the second fluid inlet / outlet protrudes from the second end wall of the sealed case to the outside. The electromagnetic valve can be made thinner. Further, when the second fluid inlet / outlet is disposed to protrude outward from the first end wall of the sealed case, the second fluid inlet / outlet is protruded in the same direction as the first fluid inlet / outlet. You can. Therefore, for example, a mounting structure in which the sealed case is mounted on the upper surface of the wiring board and both the second fluid inlet / outlet and the first fluid inlet / outlet extend downward through the wiring board is possible. Become.

In one embodiment of the electromagnetic valve, the biasing portion includes a coil spring disposed along an annular space between the side plate portion of the yoke and the outer peripheral wall of the sealing case. .

The solenoid valve according to this embodiment can be easily configured with parts having a small number of biasing portions (that is, coil springs).

In the solenoid valve of one embodiment,
The diaphragm extends spatially continuously from the center toward the peripheral edge until it covers the annular edge of the side plate portion of the yoke,
The diaphragm is provided with a notch that stops at a position corresponding to the annular edge of the side plate portion of the yoke toward the center.

In the solenoid valve of this embodiment, in the open state, the diaphragm is traversed in the one direction through the notch from the back side of the diaphragm, and the opening (the diaphragm is spaced apart from the one end) is open. ) Through the electromagnetic valve toward the first fluid inlet / outlet or vice versa.

Once the open state is closed, the peripheral edge of the inner surface of the diaphragm comes into close contact with the annular edge of the side plate portion of the yoke. Here, the notch provided in the peripheral edge portion of the diaphragm stops at a position corresponding to the annular edge of the side plate portion of the yoke toward the center. Therefore, regardless of the notch, the peripheral edge portion of the inner surface of the diaphragm closes the annular edge of the side plate portion of the yoke. Therefore, as described above, in order to maintain the closed state, the magnetic force to be generated by the solenoid coil can be reduced against the biasing force by the biasing portion. Therefore, in this solenoid valve, a small amount of current is supplied to the solenoid coil, and power saving can be achieved. In particular, in the electromagnetic valve of this embodiment, the diaphragm extends spatially continuously from the center toward the peripheral edge until it covers the annular edge of the side plate portion of the yoke. Therefore, the pressing force by the back side pressure is further increased. Therefore, this solenoid valve can further save power.

In the solenoid valve according to an embodiment, in the closed state, the inner surface of the diaphragm and a peripheral end surface around the opening of the one end portion of the pole piece, or an annular edge of the side plate portion of the yoke. An elastic coating is provided on the inner surface of the diaphragm, the peripheral end surface around the opening, or the annular edge of the side plate portion of the yoke so as to be in close contact with each other. It is characterized by being.

In the electromagnetic valve of this embodiment, thanks to the elastic coating, in the closed state, the inner surface of the diaphragm and the peripheral end surface around the opening of the one end of the pole piece, or the above The annular edge of the side plate portion of the yoke is securely in contact with each other. Therefore, in order to maintain the closed state, the magnetic force that should be generated by the solenoid coil is surely small against the urging force of the urging portion. Therefore, with this solenoid valve, power saving can be achieved reliably.

In another aspect, the blood pressure monitor of this disclosure is
A sphygmomanometer that measures the blood pressure of a measurement site,
The body,
A cuff attached to the measurement site;
A pump mounted on the body for supplying fluid to the cuff through a flow path;
The electromagnetic valve mounted on the main body and interposed between the pump or the flow path and the atmosphere;
A pressure controller for controlling the pressure of the cuff by supplying fluid to the cuff through the flow path by the pump and / or discharging the fluid from the cuff through the electromagnetic valve;
A blood pressure calculator that calculates blood pressure based on the pressure of the fluid contained in the cuff,
The solenoid valve is characterized in that the rear surface of the diaphragm is inserted with the side communicating with the pump or the flow path, and the first fluid inlet / outlet facing the atmosphere side.

In the sphygmomanometer of this disclosure, typically, the main body and the cuff are integrally attached to the measurement site. In this mounted state, the pressure control unit supplies the fluid to the cuff through the flow path by the pump and / or discharges the fluid from the cuff through the electromagnetic valve to control the pressure of the cuff. The blood pressure calculator calculates blood pressure based on the pressure of the fluid contained in the cuff. Here, in this sphygmomanometer, the electromagnetic valve is composed of an electromagnetic valve that can be configured in a small size according to the present disclosure. Accordingly, the main body, and thus the entire blood pressure monitor, can be configured in a small size.

In this sphygmomanometer, the solenoid valve is inserted such that the back surface of the diaphragm communicates with the pump or the flow path, and the first fluid inlet / outlet faces the atmosphere side. Therefore, once the solenoid valve is changed from the open state to the closed state during the pressurization control of the cuff by the pressure control unit, the solenoid is resisted against the biasing force by the biasing unit in order to maintain the closed state. The magnetic force to be generated by the coil is small. Therefore, in this sphygmomanometer, the energization amount of the solenoid valve to the solenoid coil is small, and power saving can be achieved.

In another aspect, the blood pressure monitor of this disclosure is
A sphygmomanometer that measures the blood pressure of a measurement site,
The body,
With a cuff attached to the measurement site,
The cuff includes a measurement fluid bag disposed in contact with the measurement site, and a pressing fluid bag disposed on the outer peripheral side of the measurement fluid bag,
A pump mounted on the main body for supplying fluid to the pressing fluid bag and the measuring fluid bag;
A first flow path connecting the pump and the pressing fluid bag so as to allow fluid flow;
A second flow path in which the pump or the first flow path and the measurement fluid bag are connected so as to allow fluid flow, and an on-off valve is inserted;
A pressure control unit that performs control for supplying the fluid to the pressing fluid bag from the pump through the first flow path and compressing the measurement site;
A blood pressure calculator that calculates blood pressure based on the pressure of the fluid contained in the fluid bag for measurement,
The on-off valve consists of the solenoid valve,
In the second flow path, the on-off valve is inserted with the rear surface of the diaphragm facing the upstream side communicating with the pump and the first fluid inlet / outlet facing the downstream side communicating with the measurement fluid bag. It is characterized by.

In the sphygmomanometer according to the present disclosure, when the cuff is attached to the measurement site, the measurement fluid bag contained in the cuff is disposed in contact with the measurement site. Further, the pressing fluid bag enclosed in the cuff is disposed so as to overlap the outer peripheral side of the measuring fluid bag.

At the time of blood pressure measurement, for example, the solenoid coil is turned off and the on-off valve is kept open, and the fluid is supplied from the pump to the pressing fluid bag through the first flow path. The fluid is supplied from the pump or the first channel through the second channel by a predetermined amount. Next, the solenoid coil is energized, and the on-off valve is switched from the open state to the closed state. Next, the pressure control unit keeps the on-off valve in a closed state, supplies the fluid from the pump to the pressing fluid bag through the first flow path, and passes the measured fluid bag through the measuring fluid bag. Squeeze the area. In the pressurizing process or the depressurizing process of the pressing fluid bag, the blood pressure calculating unit calculates the blood pressure based on the pressure of the fluid contained in the measuring fluid bag (oscillometric method).

Here, in the sphygmomanometer, the measurement fluid bag detects the pressure itself applied to the artery passage portion of the measurement site. Therefore, for example, as a result of setting the width direction dimension of the cuff to be small (for example, about 25 mm), the pressing fluid bag expands greatly in the thickness direction during pressurization, and a compression loss occurs in the pressing fluid bag itself. Even in this case, the blood pressure can be accurately measured based on the pressure in the measurement fluid bag.

In the sphygmomanometer, in the second flow path, the opening / closing valve includes an upstream side where the back surface of the diaphragm communicates with the pump, and a downstream side where the first fluid inlet / outlet communicates with the measurement fluid bag. Is inserted and pointed to. Therefore, the on-off valve is switched from the open state to the closed state, and in order to maintain the closed state while the closed state is maintained by the pressure control unit, the biasing force by the biasing unit is resisted. Thus, the magnetic force to be generated by the solenoid coil is small. Therefore, in this sphygmomanometer, the energization amount of the solenoid valve to the solenoid coil is small, and power saving can be achieved.

In yet another aspect, the blood pressure measurement method of this disclosure includes:
A blood pressure measurement method for measuring blood pressure at a measurement site using the sphygmomanometer,
With the cuff attached to the part to be measured, the solenoid coil is de-energized, the open / close valve is kept open, and the fluid is transferred from the pump to the pressing fluid bag through the first flow path. And a preliminary supply step of supplying a predetermined amount of the fluid from the pump or the first flow path through the second flow path,
A switching step of switching the solenoid valve from an open state to a closed state by energizing the solenoid coil;
While maintaining the on-off valve in a closed state, the pressure control unit supplies the fluid to the pressing fluid bag from the pump through the first flow path and compresses the measurement site, while the blood pressure calculation unit A blood pressure calculation step for calculating a blood pressure based on the pressure of the fluid contained in the measurement fluid bag,
The energization amount of the solenoid coil is set to be smaller than the energization amount of the solenoid coil immediately after being switched to the closed state during the period of being kept in the closed state.

In this blood pressure measurement method, first, with the main body and the cuff extending from the main body being integrally attached to the measurement site, the solenoid coil is not energized and the on-off valve is kept open. The fluid is supplied from the pump to the pressing fluid bag through the first flow path, and the fluid is supplied in a predetermined amount from the pump or the first flow path through the second flow path. (Preliminary supply step). Next, the solenoid coil is energized to switch the on-off valve from the open state to the closed state (switching step). Next, the blood pressure is maintained while the on-off valve is kept closed and the pressure control unit supplies the fluid to the pressing fluid bag from the pump through the first flow path to compress the measurement site. The blood pressure is calculated based on the pressure of the fluid contained in the fluid bag for measurement by the calculation unit (blood pressure calculation third step).

Here, in the sphygmomanometer, in the second flow path, the open / close valve is configured such that the rear surface of the diaphragm communicates with the pump upstream, and the first fluid inlet / outlet communicates with the measurement fluid bag. It is directed to the side. Therefore, the on / off valve is switched from the open state to the closed state (switching step), and during the period in which the closed state is maintained by the pressure control unit, the biasing unit applies the bias to maintain the closed state. The magnetic force to be generated by the solenoid coil against the force is small. Therefore, in this blood pressure measurement method, the energization amount of the solenoid coil is set to be smaller than the energization amount of the solenoid coil immediately after switching to the closed state during the period in which the closed state is maintained. . As a result, the energization amount of the solenoid valve to the solenoid coil is small, and power saving can be achieved.

In yet another aspect, the device of this disclosure is
A device capable of measuring the blood pressure of a measurement site,
The body,
A cuff that extends from the main body and is attached to the measurement site;
A pump mounted on the body for supplying fluid to the cuff;
The solenoid valve mounted on the body;
A pressure controller that controls the pressure of the cuff by supplying fluid to the cuff by the pump and / or discharging the fluid from the cuff through the solenoid valve;
And a blood pressure calculator that calculates blood pressure based on the pressure of the fluid contained in the cuff.

In the device of this disclosure, typically, the main body and the cuff are integrally attached to the measurement site. In this mounted state, the pressure control unit supplies the fluid to the cuff by the pump and / or discharges the fluid from the cuff through the electromagnetic valve to control the pressure of the cuff. The blood pressure calculation unit calculates blood pressure based on the pressure of the fluid contained in the cuff (oscillometric method). Here, in this device, the solenoid valve is composed of a solenoid valve that can be configured in a small size according to the present disclosure. Therefore, the main body, and thus the entire device, can be configured in a small size, and power can be saved.

As apparent from the above, the solenoid valve, blood pressure monitor, and device of the present invention can be configured in a small size and can save power. Further, according to the blood pressure measurement method of the present invention, power saving of the sphygmomanometer can be achieved.

It is a perspective view which shows the external appearance of the solenoid valve of one Embodiment of this invention. It is a figure which shows the place which looked at the said solenoid valve from the diagonal in the decomposition | disassembly state. It is a figure which shows the place which looked at the thing of FIG. 2 from another direction. It is a figure which shows an example (Example 1) of a cross-section when the said solenoid valve is cut | disconnected by the surface containing a fluid inlet / outlet. It is a figure which shows the planar shape of the diaphragm provided in the case of the solenoid valve of the said Example 1. FIG. It is a figure which shows the flow of the fluid which passes along this solenoid valve, when the solenoid valve of the said Example 1 exists in an open state. It is a figure which shows the force added to each part of this solenoid valve, when the solenoid valve of the said Example 1 exists in a closed state. FIG. 4 is a diagram showing another example (Example 2) of a cross-sectional structure when the electromagnetic valve shown in FIGS. 1 to 3 is cut along a plane including a fluid inlet / outlet. It is a figure which shows the planar shape of the diaphragm provided in the case of the solenoid valve of the said Example 2. FIG. It is a figure which shows the flow of the fluid which passes along this solenoid valve, when the solenoid valve of the said Example 2 exists in an open state. It is a figure which shows the force added to each part of this solenoid valve, when the solenoid valve of the said Example 2 exists in a closed state. FIG. 5 is a view showing a cross-sectional structure when the electromagnetic valve of the comparative example is cut along a plane including a fluid inlet / outlet corresponding to FIG. It is a figure which shows the planar shape of the diaphragm provided in the case of the solenoid valve of the said comparative example. It is a figure which shows the flow of the fluid which passes along this solenoid valve, when the solenoid valve of the said comparative example is in an open state. It is a figure which shows the force added to each part of this solenoid valve, when the solenoid valve of the said comparative example is in a closed state. It is a figure which shows the block configuration of the sphygmomanometer of one Embodiment of this invention provided with each said solenoid valve as an on-off valve. It is a figure which shows the operation | movement flow of the said blood pressure meter. It is a figure which shows the flow of the pressurization speed control contained in the operation | movement flow of FIG. 17A. FIG. 18A is a diagram showing the relationship between the driving force of the solenoid valve and the opening when the on-off valve is the solenoid valve of the first embodiment. FIG. 18B is a diagram showing the relationship between the driving force of the solenoid valve and the opening when the on-off valve is the solenoid valve of the second embodiment. FIG. 18C is a diagram showing a trajectory of the relationship between the driving force and the opening degree of the solenoid valve when the on-off valve is a comparative solenoid valve. FIGS. 19A and 19B are diagrams showing an example of an electromagnetic valve obtained by modifying the case of the electromagnetic valve shown in FIGS. 20 (A) and 20 (B) are diagrams showing another example of the solenoid valve obtained by modifying the case of the solenoid valve shown in FIGS. 1 to 3.

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

FIG. 1 shows a perspective view of an external appearance of a solenoid valve (the whole is denoted by reference numeral 2) according to an embodiment of the present invention. FIG. 2 shows the electromagnetic valve 2 in an exploded state. FIG. 3 shows that FIG. 2 is viewed from another direction. For easy understanding, XYZ orthogonal coordinates are also shown in FIGS. 1 to 3 and FIGS. 4 to 15 and 19 to 20 described later. Hereinafter, for convenience, the Z direction may be referred to as a thickness direction, and the XY direction may be referred to as a plane direction.

(Configuration of solenoid valve)
As can be seen from FIG. 1, the electromagnetic valve 2 includes a case 10 as a housing. The case 10 includes a lid case 10A disposed on one side in the thickness direction (+ Z side) and a main case 10B disposed on the opposite side in the thickness direction (−Z side). In this example, the lid case 10A includes a disk-shaped second end wall 10-2 forming an outer wall, and a cylindrical portion 10a (fluid) protruding from the center of the second end wall 10-2 to the outside (+ Z side). And a second fluid inlet / outlet port 12 for passing the fluid. The main case 10B has a rectangular (in this example, square) plate-shaped first end wall 10-1 and a substantially cylindrical outer peripheral wall 10-3 connected to the first end wall 10-1. ing. As shown in FIG. 3, a through hole 10w into which a pole piece 4 described later is fitted is provided in the center of the first end wall 10-1. In addition, a through hole 10u through which a wiring (a lead wire (not shown)) passes is provided on one side (in this example, the side on the -Y side) of the first end wall 10-1.

Connection terminals

71, 72, 73, and 74 (reference) made of metal (such as copper) are integrally provided at the four corners of the outer surface of the first end wall 10-1.

In this example, the lid case 10A is formed by integrally molding a nonmagnetic plastic material. The main case 10B is formed by integrally molding (insert molding) a nonmagnetic plastic material together with the

connection terminals

71, 72, 73, and 74. In this example, the second end wall 10-2 of the lid case 10A is welded to the outer peripheral wall 10-3 of the main case 10B. However, the present invention is not limited to this, and the second end wall 10-2 may be screwed to the outer peripheral wall 10-3.

As can be seen from FIG. 2 and FIG. 3, inside the case 10 of the electromagnetic valve 2, a yoke 3 and a pole piece 4 integrally attached perpendicularly to the yoke 3 (end plate portion 3 b), A solenoid coil 7, a coil spring 5 as an urging portion, a diaphragm 6, and an elastic body 8 formed integrally with the diaphragm 6 are provided.

As shown in FIG. 2, the yoke 3 is connected to the end plate portion 3b having an annular (circular in this example) peripheral edge, and the peripheral edge of the end plate portion 3b, and on one side (+ Z side) of the end plate portion 3b. And a side plate portion 3c surrounding the adjacent space SP1 in a ring shape. As shown in FIG. 3, a through hole 3w is provided in the center of the end plate portion 3b, and a pole piece 4 is fitted in the through hole 3w. A portion of the peripheral edge of the end plate portion 3b corresponding to the through hole 10u of the first end wall 10-1 of the main case 10B is provided with a through hole 3u through which wiring (lead wire not shown) is passed. ing. The shape of the peripheral edge of the end plate portion 3b of the yoke 3 is not limited to a circle, and may be a rounded square (a square with rounded corners). The same applies to the annular shape of the side wall portion of the side plate portion 3c.

In this example, the outer diameter of the side plate portion 3c of the yoke 3 is set smaller than the inner diameter of the outer peripheral wall 10-3 of the main case 10B. Thereby, in the assembled state shown in FIG. 4, an annular space SP2 for accommodating the coil spring 5 is formed between the side plate portion 3c of the yoke 3 and the outer peripheral wall 10-3 of the main case 10B.

2 and 3, the pole piece 4 has a substantially cylindrical shape as a whole. The pole piece 4 has a projection 4a that fits into the through-hole 3w of the yoke 3 and protrudes outside in the axial direction (Z direction), and a main portion having an outer diameter larger than the outer diameter of the projection 4a. 4b. That is, this pole piece 4 is orthogonal to the end plate portion 3b of the yoke 3 in one direction (from one end portion 4e existing in the space SP1 on one side (+ Z side) to the other end portion 4f on the opposite side (−Z side) ( Z direction). Further, in this example, the pole piece 4 has a recess 4d having a circular planar shape that opens toward the elastic body 8 of the diaphragm 6 at one end 4e. A circular opening 4o is opened at the bottom of the recess 4d. A circular first fluid inlet / outlet port 11 communicating with the opening 4 o through the pole piece 4 is provided at the other end portion 4 f of the pole piece 4.

In this example, the yoke 3 and the pole piece 4 are each made of SUM24L (sulfur composite free cutting steel) which is a magnetic material. In this example, the protrusion 4a of the pole piece 4 is press-fitted into the through hole 3w of the yoke 3, so that the yoke 3 and the pole piece 4 are integrally formed. Thereby, the magnetic resistance between the pole piece 4 and the yoke 3 is small, and the efficiency of the magnetic circuit using them as a path is increased. Moreover, the airtightness between the pole piece 4 and the yoke 3 can be improved, and air leakage can be prevented. Note that the yoke 3 and the pole piece 4 may be configured as a spatially continuous unit.

In this example, as shown in FIG. 4, a coating 9 </ b> A having elasticity is provided on the entire periphery of the peripheral end surface 4 e 1 around the opening 4 o in the one end portion 4 e of the pole piece 4. Called Example 1).

As can be seen from FIGS. 2 and 3, the solenoid coil 7 has a compact cylindrical outer shape. The dimensions of the solenoid coil 7 are set such that the solenoid coil 7 can be accommodated in an annular space SP1 between the pole piece 4 and the side plate portion 3c of the yoke 3. A pair of lead wires (not shown) extend from the solenoid coil 7.

The coil spring 5 has a substantially cylindrical outline. The coil spring 5 is disposed along the annular space SP2 between the side plate portion 3c of the yoke 3 and the outer peripheral wall 10-3 of the main case 10B in the assembled state shown in FIG. In a manner of parallel movement in the direction (Z direction), the pole piece 4 is biased in a direction away from the one end 4e (that is, + Z direction). In FIG. 4, a biasing force f <b> 2 in which the coil spring 5 biases the diaphragm 6 is schematically indicated by an arrow. Thereby, it can be simply comprised with components (namely, coil spring 5) with few energizing parts.

2 and 3, the diaphragm 6 has a substantially disk-shaped outer shape. In this example (Embodiment 1), as can be seen from FIG. 5 (showing the planar shape of the diaphragm 6), an equiangular pitch between the center 6c and the peripheral edge 6e with respect to the radial direction of the diaphragm 6 and with respect to the circumferential direction. In this example, four circular through

holes

6s, 6t, 6u, 6v are provided. As a result, fluid can flow through the through

holes

6s, 6t, 6u, and 6v between the rear surface (surface facing the + Z side) 6a side and the inner surface (surface facing the -Z side) 6b side of the diaphragm 6. ing. The diaphragm 6 is spatially partially interrupted in the direction in which the through

holes

6s, 6t, 6u, and 6v exist from the center 6c toward the peripheral edge 6e. As a result, in this example, the diaphragm 6 corresponds to a peripheral end surface 4e1 (a portion provided with the coating 9A) around the opening 4o in at least one end portion 4e of the pole piece 4 from the center 6c toward the peripheral edge portion 6e. ) Are continuously extended spatially so as to cover the entire circumference. Thereby, in the closed state described later, the inner surface 6b of the diaphragm 6 is in close contact with the peripheral end surface 4e1 of the one end portion 4e of the pole piece 4 through the coating 9A.

As can be seen from FIG. 4, the diaphragm 6 has a dimension extending over the annular edge 3 e of the side plate portion 3 c of the yoke 3. As a result, the outer diameter of the diaphragm 6 substantially matches the outer diameter of the coil spring 5. There is a slight gap between the outer diameter of the diaphragm 6 and the inner diameter of the outer peripheral wall 10-3 of the main case 10B so that the diaphragm 6 can move in one direction (Z direction) within the outer peripheral wall 10-3. Is provided.

In this example, the diaphragm 6 is substantially disc-shaped as described above, and is made of permalloy (Ni—Fe alloy) as a magnetic material. Thereby, the diaphragm 6 can be comprised lightly compared with a rod-shaped movable iron core, for example. In that case, when the posture (orientation) of the electromagnetic valve 2 changes in various directions with respect to the vertical direction, the characteristics (for example, the current-flow-current characteristic) are hardly affected by the posture of the electromagnetic valve 2.

As can be seen from FIGS. 2 and 3, the diaphragm 6 has a substantially cylindrical elastic member for closing the opening 4 o opposite to the opening 4 o formed in the recess 4 d of the one end 4 e of the pole piece 4. The body 8 is attached integrally. In this example, the elastic body 8 is made of silicone rubber. However, it is not restricted to this, The elastic body 8 may consist of other elastic materials (flexible material), such as nitrile rubber (NBR) and ethylene propylene diene rubber (EPDM). The outer diameter of the elastic body 8 is set larger than the diameter of the opening 4o and smaller than the inner diameter of the recess 4d. Thereby, the elastic body 8 can block | close the opening 4o reliably in the state accommodated in the hollow 4d of the one end part 4e of the pole piece 4 at the time of the closed state mentioned later.

In this example, the elastic body 8 is integrally attached to the diaphragm 6 by insert molding. Thereby, the diaphragm 6 and the elastic body 8 can be easily attached integrally. However, the invention is not limited to this, and the elastic body 8 may be attached to the diaphragm 6 by press-fitting, bonding, or the like.

(Solenoid valve assembly procedure)
The assembly of the electromagnetic valve 2 is performed, for example, in the following procedure from the state shown in FIGS. 2 and 3 (disassembled state).
i) First, the yoke 3 and the pole piece 4 are accommodated in the main case 10B. At this time, the pole piece 4 is fitted into the through hole 10w of the first end wall 10-1 of the main case 10B through the protrusion 4a. At the same time, the through hole 3u of the end plate portion 3b of the yoke 3 is made to correspond to the through hole 10u of the first end wall 10-1 of the main case 10B.
ii) Next, the solenoid coil 7 is accommodated in the annular space SP1 between the pole piece 4 and the side plate portion 3c of the yoke 3. At that time, a pair of lead wires (not shown) extending from the solenoid coil 7 are connected to the through hole 3u of the end plate portion 3b of the yoke 3 and the through hole 10u of the first end wall 10-1 of the main case 10B. And is pulled out of the main case 10B.
iii) Next, a pair of lead wires drawn out are soldered one by one to any two of the four

connection terminals

71, 72, 73, 74 provided on the outer surface of the first end wall 10-1. Attach. The remaining two of the four

connection terminals

71, 72, 73, 74 are left as dummy terminals.
iv) Next, the yoke 3 is bonded to the main case 10B, and the solenoid coil 7 is bonded to the yoke 3 in an airtight manner with an adhesive. At that time, the through hole 3u of the end plate portion 3b of the yoke 3 through which the pair of lead wires pass and / or the through hole 10u of the first end wall 10-1 of the main case 10B are filled with an adhesive. And get airtight.
v) Next, the coil spring 5 is accommodated in the annular space SP2 (see FIG. 4) between the side plate portion 3c of the yoke 3 and the outer peripheral wall 10-3 of the main case 10B.
vi) Subsequently, the diaphragm 6 is arranged from one side (+ Z side) of the coil spring 5 so as to face the end plate portion 3b of the yoke 3 through the space SP1. Further, while pushing the diaphragm 6 against the urging force f2 of the coil spring 5 with the lid case 10A, the second end wall 10-2 of the lid case 10A exceeds the outer peripheral wall 10-3 of the main case 10B. It is welded airtight by sonic welding.
In this way, the electromagnetic valve 2 is assembled as shown in FIG.

In the assembled state of FIG. 4, the case 10 is a sealed case, and the yoke 3 and the main part of the pole piece 4 with the protrusion 4 a (including the other end 4 f) of the pole piece 4 exposed to the outside. 4b, the solenoid coil 7, the diaphragm 6 (and the elastic body 8), and the coil spring 5 are collectively and airtightly covered. The first end wall 10-1 of the main case 10B is along the outer surface (the surface facing the -Z side) of the end plate portion 3b of the yoke 3, while the second end wall 10-2 of the lid case 10A is the diaphragm 6 It is in a state along the rear surface (surface facing the + Z side) 6a. In particular, in this example, the protrusion 4a of the pole piece 4 that forms the first fluid inlet / outlet 11 protrudes from the first end wall 10-1 to the outside, and the cylindrical portion 10a that forms the second fluid inlet / outlet 12 2 projecting outward from the end wall 10-2. Accordingly, the first fluid inlet / outlet port 11 and the second fluid inlet / outlet port 12 can be easily connected to, for example, the downstream side and the upstream side of the flow path so as to allow fluid flow. Thereby, this electromagnetic valve 2 can be easily inserted in the flow path.

(Solenoid valve opening / closing operation)
When this electromagnetic valve 2 is used, as described above, the first fluid inlet / outlet port 11 and the second fluid inlet / outlet port 12 are connected to the downstream side and the upstream side of the flow path so as to allow fluid flow, respectively. Is inserted into the flow path. As shown in FIG. 6, in this solenoid valve 2, when the solenoid coil 7 is in a non-energized state, the diaphragm 6 is separated from the one end portion 4e of the pole piece 4 by the biasing force f2 by the coil spring 5. As a result, the elastic body 8 is separated from the opening 4o of the one end 4e of the pole piece 4, and the opening 4o is opened. That is, this solenoid valve 2 is a normally open valve.

When in this open state, fluid flow through the solenoid valve 2 is allowed. If the electromagnetic valve 2 is in an open state, for example, fluid enters from the second fluid inlet / outlet port 12 as indicated by an arrow LA1. This fluid passes through the through

holes

6s, 6t, 6u, 6v of the diaphragm 6 as shown by the arrows LA2s, LA2u, and subsequently, a gap between the recess 4d of the one end 4e of the pole piece 4 and the elastic body 8. And flows out from the first fluid inlet / outlet port 11 as shown by an arrow LA3 through the opening 4o of the one end 4e. Thus, the fluid can flow through the electromagnetic valve 2 from the second fluid inlet / outlet 12 toward the first fluid inlet / outlet 11 or vice versa.

When the solenoid coil 7 is energized, as shown in FIG. 7, the biasing force of the coil spring 5 is generated by the magnetic force F0 generated by the solenoid coil 7 (the resultant force of the magnetic forces f0, f0,... Applied to each part of the diaphragm 6). The diaphragm 6 is formed on the pole piece 4 against the repulsive force f2 ′ (the resultant force of these f2 and f2 ′ is expressed as a drag force F2) received by the elastic body 8 from f2 and the recess 4d of the end 4e of the pole piece 4. By approaching the one end portion 4e, the elastic body 8 can close the opening 4o of the one end portion 4e of the pole piece 4. Specifically, when the solenoid coil 7 is in an energized state (at the time of operation), the lines of magnetic force generated by the solenoid coil 7 are mainly the side plates of the yoke 3 as indicated by a two-dot chain line M in FIG. 3c reaches the periphery of the end plate portion 3b, reaches from the periphery of the end plate portion 3b through the end plate portion 3b to an orthogonal position between the end plate portion 3b and the pole piece 4, and passes through the pole piece 4 from this orthogonal position. It reaches one end 4e, reaches from the one end 4e to a position where the one end 4e approaches the diaphragm 6, and further circulates through a path (magnetic circuit) that reaches the annular edge 3e of the side plate 3c of the yoke 3 through the diaphragm 6. If the direction of energization to the solenoid coil 7 is reversed, the lines of magnetic force generated by the solenoid coil 7 circulate in this direction in the reverse direction. As a result, the solenoid coil 7 generates a magnetic force F <b> 0 against the urging force f <b> 2 by the coil spring 5 with respect to the diaphragm 6. Due to this magnetic force F0, the diaphragm 6 approaches the one end 4e of the pole piece 4, and the opening 4o can be closed by the elastic body 8. When in the closed state, the fluid flow through the pole piece 4 is blocked. As described above, the solenoid valve 2 is in an open state or a closed state depending on whether the solenoid coil 7 is in a non-energized state (during operation) or whether the solenoid coil 7 is in a conduction state (during operation). be able to. Thereby, the flow of the fluid through the pole piece 4, that is, through the electromagnetic valve 2 can be allowed or blocked.

Furthermore, in this solenoid valve 2, when closed, the inner surface 6b of the diaphragm 6 is in close contact with the peripheral end surface 4e1 of the one end 4e of the pole piece 4 through the coating 9A. Therefore, the closed state can be assisted.

As the open / close state of the solenoid valve 2, there is an intermediate state in which the flow rate is controlled according to the energization amount of the solenoid between the closed state and the open state. When transitioning from the open state to the closed state, the elastic body 8 of the diaphragm 6 approaches the opening 4 o of the one end 4 e of the pole piece 4. Thereby, a stable energization current (or drive voltage) versus flow rate characteristic can be obtained.

Here, in this solenoid valve 2, the plate-like diaphragm 6 approaches the one end 4 e of the pole piece 4 in a posture facing the end plate 3 b of the yoke 3 in order to allow or block the fluid flow. Alternatively, it is configured to move in parallel in one direction (Z direction) in the direction of separation. That is, unlike the conventional example (in which the movable iron core is rod-shaped and moves along its longitudinal direction), in this solenoid valve 2, the plate-like diaphragm 6 is perpendicular to the plate surface of the diaphragm 6. Move in the direction (Z direction). Therefore, the size of the solenoid valve 2 can be reduced in one direction (Z direction) in which the diaphragm 6 moves. As a result, the electromagnetic valve 2 can be configured in a small size.

In particular, in the electromagnetic valve 2, the first and second end walls 10-1, 10-1, 10-2 are set by reducing the size of the case 10 from the first end wall 10-1 to the second end wall 10-2. It can have a flat outline along 10-2. Such an outer shape is suitable for mounting the electromagnetic valve 2 (case 10) along, for example, a wiring board and forming the electromagnetic valve 2 (case 10) and the wiring board together in a flat shape as a whole.

In this example, as shown in FIG. 1, the thickness (Z-direction dimension) H of the case 10 is set to about 2.5 mm. In addition, the planar dimension (XY dimension) W1, W2 of the case 10 is set to about 5.5 mm. Thus, the case 10 has a flat outer shape. In this example, the dimension in which the cylindrical portion 10a of the lid case 10A protrudes from the second end wall 10-2 to the + Z side is set to about 1.6 mm. The outer diameter and inner diameter of the cylindrical portion 10a are set to about 1.3 mm and about 0.8 mm, respectively. Further, the dimension in which the protrusion 4a of the pole piece 4 protrudes from the first end wall 10-1 of the main case 10B to the -Z side is set to about 1.6 mm. The outer diameter and inner diameter of the protrusion 4a of the pole piece 4 are set to about 1.3 mm and about 0.5 mm, respectively. Thus, the solenoid valve 2 can be configured in a small size.

Further, as a result of the electromagnetic valve 2 being configured in a small size as described above, the electromagnetic valve 2 can be reduced in weight. In particular, instead of the rod-like movable iron core of the conventional solenoid valve, the solenoid valve 2 includes a plate-like diaphragm 6 made of permalloy, so that the solenoid valve 2 can be reduced in weight. Even if the posture of the solenoid valve 2 changes variously with respect to the vertical direction, there is little change in characteristics (for example, current-flow characteristic versus flow characteristic). Therefore, the electromagnetic valve 2 can be opened and closed stably and reliably.

(Application to blood pressure monitor)
FIG. 16 shows a schematic block configuration of a sphygmomanometer 100 according to an embodiment provided with the above-described electromagnetic valve 2 as the on-off valve 33. The sphygmomanometer 100 roughly includes a cuff 20 attached to a measurement site 90 such as a wrist or an upper arm, and a main body 100M. An artery 91 passes through the measurement site 90.

The cuff 20 includes a sensing cuff 21 as a measurement fluid bag disposed in contact with the measurement site 90, and a press cuff 23 as a pressing fluid bag disposed on the outer periphery side of the sensing cuff 21. It is out. A reinforcing plate for effectively transmitting the pressure of the pressing cuff 23 to the measurement site 90 via the sensing cuff 21 may be disposed between the pressing cuff 23 and the sensing cuff 21.

The main body 100M includes an opening / closing unit including a control unit 110, a display 50, a memory 51 as a storage unit, an operation unit 52, a power supply unit 53, a pump 30, an exhaust valve 34, and the electromagnetic valve 2 described above. A valve 33, a first pressure sensor 31 for detecting the pressure of the pressing cuff 23, and a second pressure sensor 32 for detecting the pressure of the sensing cuff 21 are mounted.

The display device 50 includes a display, an indicator, and the like, and displays predetermined information (for example, blood pressure measurement result) according to a control signal from the control unit 110.

The operation unit 52 includes a switch that receives an input of an instruction for turning the power supply unit 53 on (on) or off (off). The operation unit 52 inputs an operation signal according to an instruction from the user to the control unit 110.

The memory 51 is data of a program for controlling the sphygmomanometer 100, data used for controlling the sphygmomanometer 100, setting data for setting various functions of the sphygmomanometer 100, and data of blood pressure value measurement results Memorize etc. The memory 51 is used as a work memory when the program is executed.

The control unit 110 includes a CPU (Central Processing Unit) and controls the overall operation of the sphygmomanometer 100. Specifically, the control unit 110 works as a pressure control unit according to a program for controlling the sphygmomanometer 100 stored in the memory 51, and in response to an operation signal from the operation unit 52, the pump 30 and the on-off valve 33. Etc. are controlled. The control unit 110 also functions as a blood pressure calculation unit, calculates a blood pressure value, and controls the display 50 and the memory 51. A specific method for measuring blood pressure will be described later.

In this example, the power supply unit 53 is composed of a rechargeable secondary battery. The power supply unit 53 supplies power to each unit in the main body 100M, such as the control unit 110 and the pump 30.

The pump 30 is a piezoelectric pump in this example, and is driven based on a control signal supplied from the control unit 110. This pump 30 is connected to the press cuff 23 through a first flow path 390 (including

partial flow paths

390a, 390b, and 390c in series) provided in the main body 100M so that fluid can flow. Yes.

In this example, the exhaust valve 34 is a known passive valve connected to the pump 30 via a flow path 391, and is opened and closed as the pump 30 is turned on (started) / off (stopped). That is, this exhaust valve closes when the pump 30 is turned on and helps to enclose air in the pressure cuff 23, while it opens when the pump 30 is turned off to allow the air in the pressure cuff 23 to enter the atmosphere 900. To discharge. The exhaust valve 34 has a check valve function, and the discharged air does not flow backward.

In this example, the on-off valve 33 is inserted into a second flow path 380 (including

partial flow paths

380a, 380b, and 380c in series) that connects the first flow path 390 and the sensing cuff 21. ing. In the second flow path 380, the on-off valve 33 is connected to the upstream side where the second fluid inlet / outlet 12 (on the rear face 6a side of the diaphragm 6) communicates with the pump 30 so that fluid can flow therethrough. The inlet / outlet port 11 (pole piece 4 side) is connected to the downstream side communicating with the sensing cuff 21 so that fluid can flow. The second flow path 380 may be connected between the pump 30 and the sensing cuff 21.

In this example, the first pressure sensor 31 and the second pressure sensor 32 are each composed of a piezoresistive pressure sensor. The first pressure sensor 31 detects the pressure in the pressing cuff 23 via a flow path 392 connected to the first flow path 390. The second pressure sensor 32 detects the pressure in the sensing cuff 21 via the flow path 381 connected to the second flow path 380.
(Blood pressure measurement operation)
FIG. 17A shows an operation flow when the user performs blood pressure measurement with the sphygmomanometer 100 as the blood pressure measurement method according to one embodiment of the present invention.

When the user instructs the start of measurement with the operation unit 52 provided in the main body 100M with the cuff 20 attached to the measurement site 90, the control unit 110 initializes the processing memory area (FIG. 17A). Step S1). In addition, the control unit 110 turns off the pump 30 and opens the exhaust valve 34 and maintains the on-off valve 33 in an open state to exhaust the air in the pressing cuff 23 and the sensing cuff 21. Subsequently, 0 mmHg adjustment (the atmospheric pressure is set to 0 mmHg) of the first pressure sensor 31 and the second pressure sensor 32 is performed.

Next, the control unit 110 operates as a pressure control unit, turns on the pump 30 (step S2), maintains the on-off valve 33 in an open state, and preliminarily supplies air to the pressing cuff 23 and the sensing cuff 21. (Step S3; preliminary supply step). At this time, the pump 30 is driven while monitoring the pressure of the pressure cuff 23 and the sensing cuff 21 by the first pressure sensor 31 and the second pressure sensor 32, respectively. As a result, a predetermined amount of air as a fluid is preliminarily supplied to the pressing cuff 23 through the first channel 390 and to the sensing cuff 21 through the second channel 380. In this example, the preliminary supply is performed when the pressure of the sensing cuff 21 reaches a predetermined pressure (15 mmHg in this example) or the driving time of the pump 30 is a predetermined time (in this example, 3 seconds). ) Until it passes.

Next, the control unit 110 switches the on-off valve 33 from the open state to the closed state (step S4; switching step). Subsequently, the control unit 110 temporarily turns off the pump 30 and opens the exhaust valve 34 (step S5). Thereby, the air in the press cuff 23 is exhausted through the first flow path 390 and the exhaust valve 34. At this time, the preliminarily supplied air remains in the sensing cuff 21. Therefore, when the pressing cuff 23 is pressurized in the subsequent steps, the second pressure sensor 32 can reliably detect the pressure in the sensing cuff 21. The pressure in the sensing cuff 21 detected by the second pressure sensor 32 includes a fluctuation component due to a pulse wave passing through the artery 91 of the measurement site 90 (this is referred to as a pulse wave signal).

Next, the control unit 110 operates as a pressure control unit, turns on the pump 30, closes the exhaust valve 34, and starts pressurization of the pressure cuff 23 (that is, compression of the measured portion 90) (step S6). . Thereby, the pressing cuff 23 presses the measurement site 90 via the sensing cuff 21. The pressure of the pressing cuff 23 is P0, and the pressure of the sensing cuff 21 is P1. In this example, the control unit 110 supplies air to the pressing cuff 23 from the pump 30 through the first flow path 390, and based on the output of the first pressure sensor 31 (that is, the pressure P0 of the pressing cuff 23), The pressurization speed is controlled (step S7).

Specifically, in this example, as shown in the flow of pressurization speed control in FIG. 17B, the control unit 110 determines whether or not the pressurization speed matches the target speed (step S81 in FIG. 17B). Here, if the pressurization speed matches the target speed (YES in step S81), the process directly returns to the flow of FIG. 17A. On the other hand, if the pressurization speed does not match the target speed (NO in step S81 in FIG. 17B), the process proceeds to step S82 in FIG. 17B to determine whether the pressurization speed is greater than the target speed. If the pressurization speed is higher than the target speed (YES in step S82), the drive voltage of the pump 30 is decreased from the current control voltage by a constant value [beta] [V] (step S83). On the other hand, if the pressurization speed is lower than the target speed (NO in step S82), the drive voltage of the pump 30 is increased from the current control voltage by a fixed value β [V] (step S84). Thereafter, the process returns to the flow of FIG. 17A.

When the pressure P0 of the pressure cuff 23 increases to a certain extent (about 30 to 40 mmHg or more) in this way, the influence of the air preliminarily supplied to the sensing cuff 21 is reduced, and the pressure P0 of the pressure cuff 23 The pressure P1 of the sensing cuff 21 becomes substantially equal (that is, P0≈P1).

The pressurization speed may be controlled based on the output of the second pressure sensor 32 (that is, the pressure of the sensing cuff 21 is P1) instead of the output of the first pressure sensor 31.

Next, in step S8 of FIG. 17A, the control unit 110 operates as a blood pressure calculation unit, and converts the pulse wave signal acquired at this time (the fluctuation component due to the pulse wave included in the output of the second pressure sensor 32). Based on this, an attempt is made to calculate blood pressure values (systolic blood pressure SBP (Systolic Blood Pressure) and diastolic blood pressure DBP (Diastolic Blood Pressure)) by a known oscillometric method.

At this time, if the blood pressure value cannot be calculated yet due to lack of data (NO in step S9), the cuff pressure has reached the upper limit pressure (for example, 300 mmHg is determined in advance for safety). Unless otherwise specified, the processes in steps S7 to S9 are repeated.

If the blood pressure value can be calculated in this way (YES in step S9), the control unit 110 displays the measurement result of the blood pressure value on the display 50. Further, the control unit 110 turns off the pump 30, opens the exhaust valve 34 (step S10), and opens the on-off valve 33 (step S11), and exhausts the air in the pressing cuff 23 and the sensing cuff 21. Take control.

The blood pressure calculation may be performed not in the pressurizing process of the pressing cuff 23 but in the depressurizing process.

Here, in the sphygmomanometer 100, the sensing cuff 21 detects the pressure itself applied to the arterial passage portion of the measurement site 90. Therefore, for example, as a result of setting the width direction dimension of the cuff 20 to be small (for example, about 25 mm), the pressure cuff 23 is greatly expanded in the thickness direction at the time of pressurization, and a compression loss occurs in the pressure cuff 23 itself. In addition, the blood pressure can be accurately measured based on the pressure of the sensing cuff 21.

In the sphygmomanometer 100, in the second flow path 380, the on-off valve 33 includes the first fluid inlet / outlet 11 on the upstream side where the second fluid inlet / outlet 12 (on the back surface 6 a side of the diaphragm 6) communicates with the pump 30. The (pole piece 4 side) is inserted toward the downstream side communicating with the sensing cuff 21. Therefore, during the period when the on-off valve 33 is switched from the open state to the closed state and the closed state is maintained by the control unit 110 (particularly during the processing of steps S7 to S9 in FIG. 17A), a detailed description will be given below. Thus, in order to maintain this closed state, the magnetic force that the solenoid coil 7 should generate can be reduced against the biasing force f2 and the like by the coil spring 5. Therefore, in the sphygmomanometer 100, the energization amount to the solenoid coil 7 of the electromagnetic valve 2 is small, and power saving can be achieved.

In this sphygmomanometer 100, the on-off valve 33 is composed of the electromagnetic valve 2 that is small and lightweight. Therefore, the main body 100M, and thus the entire blood pressure monitor 100, can be configured to be small and lightweight. Even if the posture of the on-off valve 33 (solenoid valve 2) changes variously with respect to the vertical direction, there is little change in characteristics (for example, energization current versus flow rate characteristics). Therefore, the on-off valve 33 can be opened and closed stably and reliably, and thus the operation of the sphygmomanometer 100 can be stabilized.

(Magnetic force to maintain the closed state)
In order to explain the magnetic force for maintaining the closed state, the electromagnetic valve of the second embodiment obtained by modifying the electromagnetic valve 2 of the first embodiment (this is represented by reference numeral 2B, as shown in FIGS. 8 to 11). ) And a comparative electromagnetic valve (represented by reference numeral 2X, shown in FIGS. 12 to 15) will be described first. In FIGS. 8 to 11 and FIGS. 12 to 15, the same components as those in FIGS. 4 to 7 are denoted by the same reference numerals, and redundant description is omitted.

FIG. 8 shows a cross-sectional structure of the electromagnetic valve 2B of Example 2 corresponding to FIG. In the electromagnetic valve 2 according to the first embodiment, the coating 9A is provided on the peripheral end surface 4e1 around the opening 4o in the one end 4e of the pole piece 4. Instead, in this electromagnetic valve 2B, the side plate of the yoke 3 is provided. A coating 9B having elasticity is provided on the entire circumference of the annular edge 3e of the portion 3c. FIG. 9 shows the planar shape of the diaphragm of the electromagnetic valve 2B of the second embodiment (this is represented by reference numeral 6B) in correspondence with FIG. In the solenoid valve 2 according to the first embodiment, four circular through

holes

6s, 6t, 6u, and 6v are provided between the center 6c and the peripheral edge 6e with respect to the radial direction of the diaphragm 6. In the electromagnetic valve 2B, a substantially arc shape that stops at a position corresponding to the annular edge 3e of the side plate portion 3c of the yoke 3 (corresponding to a portion provided with the coating 9B) toward the center 6c toward the peripheral edge 6e of the diaphragm 6B. Are provided with

notches

6i, 6j, 6k. As a result, the diaphragm 6B extends spatially and continuously so as to cover the entire circumference of the annular edge 3e of the side plate 3c of the yoke 3 from the center 6c toward the peripheral edge 6e. The electromagnetic valve 2B according to the second embodiment is configured in the same manner as the electromagnetic valve 2 according to the first embodiment in other respects.

In the electromagnetic valve 2B, in the open state shown in FIG. 10, for example, fluid enters from the second fluid inlet / outlet 12 (on the back surface 6a side of the diaphragm 6B) as indicated by an arrow LB1. This fluid passes through the

notches

6i, 6j, 6k of the diaphragm 6 as shown by arrows LB2i, LB2k, and then passes through the gap between the recess 4d of the one end 4e of the pole piece 4 and the elastic body 8. Through the opening 4o of the one end 4e, the fluid flows out from the first fluid inlet / outlet port 11 as indicated by an arrow LB3. In this way, fluid can flow through the electromagnetic valve 2B from the second fluid inlet / outlet 12 toward the first fluid inlet / outlet 11 or vice versa.

Further, in the electromagnetic valve 2B, in the closed state shown in FIG. 11, the diaphragm 6 is moved against the one end 4e of the pole piece 4 by the magnetic force F0 generated by the solenoid coil 7, as in the electromagnetic valve 2 of the first embodiment. The opening 4o is closed by the elastic body 8. Therefore, the fluid flow through the electromagnetic valve 2 can be blocked. Further, in this electromagnetic valve 2B, the peripheral edge portion 6e of the inner surface 6b of the diaphragm 6B is in close contact with the annular edge 3e of the side plate portion 3c of the yoke 3 through the coating 9B. Here, the

notches

6i, 6j, 6k provided in the peripheral edge 6e of the diaphragm 6B are stopped at a position corresponding to the annular edge 3e of the side plate 3c of the yoke 3 toward the center 6c. Therefore, regardless of the

notches

6i, 6j, 6k, the peripheral edge 6e of the inner surface 6b of the diaphragm 6B closes the annular edge 3e of the side plate 3c of the yoke 3. Therefore, the closed state can be assisted.

FIG. 12 shows a cross-sectional structure of a comparative electromagnetic valve 2X corresponding to FIG. In this electromagnetic valve 2X, the coating 9A on the peripheral end surface 4e1 around the opening 4o of the one end portion 4e of the pole piece 4 in the electromagnetic valve 2 of the first embodiment, or the side plate portion of the yoke 3 in the electromagnetic valve 2B of the second embodiment. A part corresponding to the coating 9B of the annular edge 3e of 3c is omitted. The electromagnetic valve 2X of this comparative example is configured in the same manner as the electromagnetic valve 2 of Example 1 in other respects. For example, as shown in FIG. 13, the planar shape of the diaphragm 6 of the electromagnetic valve 2X is set to be the same as that of the electromagnetic valve 2 of the first embodiment.

In the electromagnetic valve 2X, in the open state shown in FIG. 14, as in the electromagnetic valve 2 of the first embodiment, as indicated by arrows LC1, LC2s, LC2u, LC3, the first fluid inlet / outlet 12 is used to The fluid can flow through the electromagnetic valve 2X toward the fluid inlet / outlet port 11 or vice versa.

Further, in the electromagnetic valve 2X, in the closed state shown in FIG. 15, the diaphragm 6 is moved against the one end 4e of the pole piece 4 by the magnetic force F0 generated by the solenoid coil 7 as in the electromagnetic valve 2 of the first embodiment. The opening 4o is closed by the elastic body 8. Therefore, the fluid flow through the electromagnetic valve 2 can be blocked. In this closed state, the inner surface 6 b of the diaphragm 6 contacts the peripheral end surface 4 e 1 of the one end portion 4 e of the pole piece 4. However, there is nothing corresponding to the coating 9A between the inner surface 6b of the diaphragm 6 and the peripheral end surface 4e1. For this reason, as shown by arrows LX2s and LX2u, the fluid passes through the through

holes

6s, 6t, 6u, and 6v of the diaphragm 6 and passes between the inner surface 6b of the diaphragm 6 and the peripheral end surface 4e1, and thus one end of the pole piece 4. It can enter the gap between the recess 4d of 4e and the elastic body 8. For this reason, in this solenoid valve 2X, the ability to assist a closed state is not expected.

Now, in the solenoid valve 2 of the first embodiment, as shown in FIG. 5, the diaphragm 6 has a peripheral end surface 4e1 around the opening 4o in one end portion 4e of the pole piece 4 from the center 6c toward the peripheral portion 6e. It extends spatially and continuously so as to cover the entire circumference (corresponding to the portion where the coating 9A is provided). Thereby, as shown in FIG. 7, when closed, the inner surface 6b of the diaphragm 6 is in close contact with the peripheral end surface 4e1 of the one end 4e of the pole piece 4 through the coating 9A. Here, the area of the region (including the opening 4o) surrounded by the peripheral end surface 4e1 of the one end portion 4e of the pole piece 4 (referred to as Sa) is the diameter of the recess 4d of the one end portion 4e of the pole piece 4 ( When coating 9A corresponds to the inside diameter of) the a .PHI.a, the Sa = πΦa ^2/4.

In the solenoid valve 2B of the second embodiment, as shown in FIG. 9, the diaphragm 6B is formed from the center 6c toward the peripheral edge 6e, and the annular edge 3e of the side plate portion 3c of the yoke 3 (the portion provided with the coating 9B). Until it covers the entire circumference. Accordingly, as shown in FIG. 11, in the closed state, the peripheral edge portion 6e of the inner surface 6b of the diaphragm 6B is in close contact with the annular edge 3e of the side plate portion 3c of the yoke 3 through the coating 9B. The area (referred to as Sb) of the region surrounded by the annular edge 3e of the side plate portion 3c of the yoke 3 is defined as the inner diameter of the annular edge 3e of the side plate portion 3c of the yoke 3 (corresponding to the inner diameter of the coating 9B) being Φb. Then, it becomes Sb = πΦb ^2/4.

Here, the area of the opening 4o of the pole piece 4 (hereinafter referred to as S0. If the diameter of the opening 4o and [Phi, the S0 = πΦ ^2/4.) As compared with, at one end 4e of the pole piece 4 The area Sa of the closed region (including the opening 4o) is large, and the area Sb of the region surrounded by the annular edge 3e of the side plate portion 3c of the yoke 3 is large. That is, S0 <Sa <Sb. In addition, for example, the pressure of the fluid applied to the opening 4o from the first fluid inlet / outlet 11 side (substantially equal to the pressure P1 of the sensing cuff 21, this is referred to as the opening side pressure P1), and the back surface 6a of the diaphragm 6 It is assumed that the pressure of the fluid applied to the pressure (substantially equal to the pressure P0 of the pressing cuff 23, which is referred to as the back side pressure P0) is the same positive pressure (exceeds atmospheric pressure). In this case, the former relationship between the pressing force by the opening side pressure P1 (referred to as F1) and the pressing force by the back side pressure P0 (referred to as Fa for the area Sa and Fb for the area Sb) is as follows. The latter Fa and Fb are larger than F1. That is, since F1 = P1 × S0, Fa = P0 × Sa, and Fb = P0 × Sb, for example, if 0 <P1≈P0, F1 <Fa <Fb. If the back side pressure P0 is larger than the opening side pressure P1 (that is, if P1 <P0), then F1 << Fa << Fb.

As a result, in the solenoid valve 2 of the first embodiment and the solenoid valve 2B of the second embodiment, once the open state is changed to the closed state, the back side pressure P0 is equal to or higher than the open side pressure P1 (however, both are positive pressures). If so, in order to maintain the closed state, the magnetic force that the solenoid coil 7 should generate against the drag F2 (the biasing force f2 of the coil spring 5 and the repulsive force f2 'from the recess 4d to the elastic body 8). F0 is small. That is, in the solenoid valve 2, F0 = F1 + F2-Fa. In the solenoid valve 2B, F0 = F1 + F2-Fb. Therefore, for example, if 0 <P1≈P0, the magnetic force F0 to be generated by the solenoid coil 7 can be reduced by the amount of Fa and Fb larger than F1. Thereby, the closed state is assisted. Therefore, in the solenoid valve 2 of the first embodiment and the solenoid valve 2B of the second embodiment, the energization amount to the solenoid coil 7 is small, and power saving can be achieved.

On the other hand, in the electromagnetic valve 2X of the comparative example, as shown in FIG. 15, in the closed state, the fluid can enter the gap between the recess 4d of the one end 4e of the pole piece 4 and the elastic body 8. The back pressure P0 does not work as a substantial pressing force against the diaphragm 6. For this reason, even if, for example, 0 <P1≈P0, the magnetic force to be generated by the solenoid coil 7 is F0≈F1 + F2, and is not substantially reduced. That is, in the electromagnetic valve 2X of the comparative example, the closed state is not assisted.

For example, FIG. 18A, FIG. 18B, and FIG. 18C show the solenoid coil 7 for the solenoid valve 2 of Example 1, the solenoid valve 2B of Example 2, and the solenoid valve 2X of Comparative Example, respectively. The relationship between the magnetic force F0 which generate | occur | produces and the opening degree of those valves is shown. The opening degree of the valve is expressed as 100% when the valve is fully opened and 0% when the valve is fully closed. For simplicity, an intermediate state between the open state and the closed state of each valve will be ignored and described.

As shown in FIG. 18 (A), the electromagnetic valve 2 of Example 1 is first subjected to the magnetic force F0 = 0 and therefore the opening degree 100% under the conditions of the back side pressure P0 = 0 mmHg and the opening side pressure P1 = 0 mmHg. It is assumed that it is at a certain point ST1. When the energization amount of the solenoid coil 7 is increased and the magnetic force F0 is increased as shown by the solid line AQ1, in this example, the state shifts from the open state to the closed state when the magnetic force F0a1. In this example, the magnetic force F0 is temporarily stopped at a point ST2 where the magnetic force F0 slightly exceeds F0a1. Here, when the electromagnetic valve 2 is once changed from the open state to the closed state, for example, under the conditions of the back side pressure P0 = 300 mmHg and the opening side pressure P1 = 300 mmHg, as described above, to maintain the closed state. The magnetic force F0 to be generated by the solenoid coil 7 is small. In this example, when the energization amount of the solenoid coil 7 is reduced and the magnetic force F0 is reduced as shown by the broken line AQ2, the magnetic F0a1 does not return to the open state yet, and the magnetic force F0a2 (shown by the broken line AQ3). It returns to the open state when> 0). And it has returned to the first point ST1.

Therefore, in the operation flow of blood pressure measurement shown in FIG. 17A, during the period from when the solenoid valve 2 as the on-off valve 33 is closed in step S4 until it is opened in step S11, in particular, the pressure cuff 23 Even when the energization amount of the solenoid coil 7 is set to be smaller than the energization amount of the solenoid coil 7 immediately after step S4 during the period of calculating blood pressure while pressurizing (steps S7 to S9 in FIG. 17A). The closed state can be maintained. For example, the closed state can be maintained even if the energization amount of the solenoid coil 7 is set so as to be the magnetic force at the point ST3 between the magnetic force F0a1 and the magnetic force F0a2 in FIG. Thereby, power saving can be achieved.

For example, the drag force F2 (the urging force f2 of the coil spring 5 and the repulsive force f2 ′ from the depression 4d to the elastic body 8) is F2 = 5.0 × 10 ⁻² [N]. Then, under the conditions of the back side pressure P0 = 0 mmHg and the opening side pressure P1 = 0 mmHg, the magnetic force when shifting from the open state to the closed state along the arrow AQ1 in FIG. 18A is F0a1 = F2 = 5. 0 × a ¹⁰ -2 [N]. The diameter of the opening 4o is Φ = 0.5 mm, and the diameter of the recess 4d of the one end 4e of the pole piece 4 is Φa = 1.2 mm. Then, for example, under the conditions of the back side pressure P0 = 300 mmHg and the opening side pressure P1 = 300 mmHg, the pressing force by the back side pressure P0 is Fa = 4.52 × 10 ⁻² [N], and the pressing force by the opening side pressure P1 Is F1 = 7.84 × 10 ⁻³ [N]. Therefore, the magnetic force for shifting from the closed state to the open state along arrow AQ3 in FIG. 18A is F0a2 = F1 + F2-Fa≈1.3 × 10 ⁻² [N].

As shown in FIG. 18 (B), the electromagnetic valve 2B of Example 2 is first subjected to a magnetic force F0 = 0 and therefore an opening degree of 100% under the conditions of the back side pressure P0 = 0 mmHg and the opening side pressure P1 = 0 mmHg. It is assumed that it is at a certain point ST11. When the energization amount of the solenoid coil 7 is increased and the magnetic force F0 is increased as shown by the solid line BQ1, in this example, the state shifts from the open state to the closed state when the magnetic force F0b1. In this example, the magnetic force F0 is temporarily stopped at a point ST12 where the magnetic force F0 slightly exceeds F0b1. Here, in the electromagnetic valve 2B, once the state is changed from the open state to the closed state, for example, under the conditions of the back side pressure P0 = 300 mmHg and the opening side pressure P1 = 300 mmHg, The magnetic force F0 to be generated by the solenoid coil 7 is small. In this example, when the energization amount of the solenoid coil 7 is decreased and the magnetic force F0 is reduced as shown by the broken line BQ2, the magnetic flux F0b1 to the zero magnetic force is not yet returned to the open state, as shown by the broken line BQ3. It returns to the open state when the magnetic force is F0b2 (<0). Thereafter, the magnetic force F0 is returned to zero and returned to the first point ST11.

Therefore, in the operation flow of blood pressure measurement shown in FIG. 17A, during the period from when the electromagnetic valve 2B as the on-off valve 33 is closed at step S4 until it is opened at step S11, the pressure cuff 23 is particularly good. Even when the energization amount of the solenoid coil 7 is set to be smaller than the energization amount of the solenoid coil 7 immediately after step S4 during the period of calculating blood pressure while pressurizing (steps S7 to S9 in FIG. 17A). The closed state can be maintained. For example, the closed state can be maintained even if the energization amount of the solenoid coil 7 is set to zero (point ST13 of zero magnetic force in FIG. 18A). Thereby, power saving can be achieved.

For example, as in the previous example, the drag force F2 (the urging force f2 of the coil spring 5 and the repulsive force f2 ′ from the recess 4d to the elastic body 8) is F2 = 5.0 × 10 ⁻² [N]. Then, under the conditions of the back side pressure P0 = 0 mmHg and the opening side pressure P1 = 0 mmHg, the magnetic force when shifting from the open state to the closed state along the arrow BQ1 in FIG. 18B is F0b1 = F2 = 5. 0 × 10 ⁻² [N]. The diameter of the opening 4o is Φ = 0.5 mm, and the diameter of the recess 4d of the one end 4e of the pole piece 4 is Φa = 1.2 mm. Then, for example, under the conditions of the back side pressure P0 = 300 mmHg and the opening side pressure P1 = 300 mmHg, the pressing force by the back side pressure P0 is Fb = 2.82 × 10 ⁻¹ [N], and the pressing force by the opening side pressure P1 Is F1 = 7.84 × 10 ⁻³ [N]. Therefore, the magnetic force for shifting from the closed state to the open state along arrow BQ3 in FIG. 18B is F0b2 = F1 + F2-Fb = −2.2 × 10 ⁻¹ [N].

In the electromagnetic valve 2 of Example 1 and the electromagnetic valve 2B of Example 2, the energization amount (magnetic force) of the solenoid coil 7 for maintaining the closed state depends on the back side pressure P0 and the opening side pressure P1, Actually, it is desirable to set the energization amount (magnetic force) of the solenoid coil 7 continuously or stepwise in accordance with changes in the values P0 and P1.

On the other hand, as shown in FIG. 18 (C), the electromagnetic valve 2X of the comparative example is first opened under the conditions of the back side pressure P0 = 0 mmHg and the opening side pressure P1 = 0 mmHg. It is assumed that the point is at a point ST21 which is 100%. When the energization amount of the solenoid coil 7 is increased and the magnetic force F0 is increased as shown by the solid line XQ1, in this example, the state shifts from the open state to the closed state at the magnetic force F01. In this example, the magnetic force F0 is temporarily stopped at a point ST22 where it slightly exceeds F01. Here, in the electromagnetic valve 2X of this comparative example, the closed state is not assisted under the same conditions of the back side pressure P0 and the opening side pressure P1. For example, under the conditions of the back side pressure P0 = 300 mmHg and the opening side pressure P1 = 300 mmHg, when the energization amount of the solenoid coil 7 is decreased and the magnetic force F0 is reduced, the magnetic force F01 is reversed and the magnetic force F01 is substantially reduced. Sometimes it returns to the open state. Then, the process returns to the first point ST21. As a result, in the electromagnetic valve 2X of the comparative example, in order to maintain the closed state, the energization amount (the magnetic force) of the solenoid coil 7 is maintained at that point ST22.

For example, as in the previous two examples, the drag force F2 (the urging force f2 of the coil spring 5 and the repulsive force f2 ′ from the recess 4d to the elastic body 8) is expressed as F2 = 5.0 × 10 ⁻² [N]. To do. Then, under the conditions of the back side pressure P0 = 0 mmHg and the opening side pressure P1 = 0 mmHg, when shifting from the open state to the closed state along the arrow XQ1 in FIG. 18C (or vice versa) The magnetic force at the time of transition to the open state is F01≈F2 = 5.0 × 10 ⁻² [N]. The diameter of the opening 4o is Φ = 0.5 mm, and the diameter of the recess 4d of the one end 4e of the pole piece 4 is Φa = 1.2 mm.

(Application as exhaust valve)
In the examples so far, the electromagnetic valve 2 (or electromagnetic valve 2B) has been used as the on-off valve 33 in FIG. 16, but the present invention is not limited to this. The electromagnetic valve 2 (or electromagnetic valve 2B) may be used as the exhaust valve 34 in FIG.

For example, in the solenoid valve 2, as the exhaust valve 34, the second fluid inlet / outlet 12 is connected in communication with the flow path 391, and the first fluid inlet / outlet 11 is opened toward the atmosphere 900.

In such a case, in the sphygmomanometer 100, the exhaust valve 34 includes the electromagnetic valve 2 that can be configured to be small and lightweight. Therefore, the main body 100M, and thus the entire blood pressure monitor 100, can be configured to be small and lightweight. Further, even if the posture of the exhaust valve 34 (solenoid valve 2) changes variously with respect to the vertical direction, since the change in characteristics (for example, current-carrying current versus flow characteristic) is small, the opening and closing of the exhaust valve 34 can be stably performed. Therefore, the operation of the sphygmomanometer 100 can be stabilized.

Further, during the blood pressure measurement by the operation flow shown in FIG. 17A, the pressure P0 of the pressing cuff 23 is applied to the second fluid inlet / outlet 12 of the exhaust valve 34 as the back side pressure. Atmospheric pressure (0 mmHg) is applied to the first fluid inlet / outlet port 11 of the exhaust valve 34 as the opening side pressure. Once the electromagnetic valve 2 as the exhaust valve 34 is changed from the open state to the closed state, the drag force F2 (the urging force f2 of the coil spring 5 and the repulsive force f2 from the depression 4d to the elastic body 8 is maintained in order to maintain the closed state. It is possible to reduce the magnetic force F0 that the solenoid coil 7 should generate against '). Therefore, in the sphygmomanometer 100, for example, during the period from when the pump 30 is turned on and the exhaust valve 34 is closed in step S5 in FIG. 17A until the pump 30 is turned off and the exhaust valve 34 is opened in step S10. During the period when the blood pressure is calculated while pressurizing the pressing cuff 23 (steps S7 to S9 in FIG. 17A), the solenoid of the exhaust valve 34 is compared with the energization amount of the solenoid coil 7 of the exhaust valve 34 immediately after step S5. Even if the energization amount of the coil 7 is set to be small, the closed state can be maintained. Thereby, power saving can be achieved.

When the solenoid valve 2 (or solenoid valve 2B) is used as the exhaust valve 34, the sphygmomanometer 100 is not the cuff 20 (including the sensing cuff 21 and the press cuff 23) as shown in FIG. A cuff including only one general fluid bag may be provided.

(Variation related to coating arrangement)
In order to assist the closed state, in the electromagnetic valve 2 of the first embodiment shown in FIGS. 4 to 7, the coating 9A having elasticity is provided on the peripheral end surface 4e1 around the opening 4o of the one end portion 4e of the pole piece 4. Provided. Further, in the electromagnetic valve 2B of the second embodiment shown in FIGS. 8 to 11, the coating 9B having elasticity is provided on the annular edge 3e of the side plate portion 3c of the yoke 3. However, the present invention is not limited to this. For example, of the inner surface 6b of the diaphragm 6 (or 6B), a portion corresponding to the peripheral end surface 4e1 of the one end portion 4e of the pole piece 4, a portion corresponding to the annular edge 3e of the side plate portion 3c of the yoke 3, or the diaphragm An elastic coating may be provided on the entire area of the inner surface 6b of 6 (or 6B).

Thereby, in the closed state, the inner surface 6b of the diaphragm 6 (or 6B) and the peripheral end surface 4e1 around the opening 4o of the one end portion 4e of the pole piece 4 or the annular edge 3e of the side plate portion 3c of the yoke 3 are connected. Can be close to each other. Accordingly, the closed state can be assisted in the same manner as in the electromagnetic valve 2 of the first embodiment and the electromagnetic valve 2B of the second embodiment.

It should be noted that the coating provided on the inner surface 6b of the diaphragm 6 (or 6B) may be integrally and continuously formed of the same material as the elastic body 8 by integral molding. Thereby, the manufacturing process of the components of a solenoid valve can be simplified.

(Modifications related to the case)
In the above example, the second fluid inlet / outlet 12 of the

solenoid valves

2 and 2B is configured by the cylindrical portion 10a protruding outward (+ Z side) from the second end wall 10-2 of the lid case 10A. In that case, it becomes easy to insert the

solenoid valves

2 and 2B in the straight flow path. However, the present invention is not limited to this.

For example, FIGS. 19A and 19B show an example of an electromagnetic valve 2D obtained by modifying the case 10 of the electromagnetic valve 2 of the first embodiment. FIG. 19A shows the electromagnetic valve 2D viewed from the + Z side. FIG. 19B shows a cross-sectional structure viewed from the lower side (−Y side) in FIG. As can be seen from this figure, in this solenoid valve 2D, the cylindrical portion 10b forming the second fluid inlet / outlet 12 is disposed so as to protrude from the outer peripheral wall 10-3 of the main case 10B to the outside (+ X side). The other points are configured in the same manner as the electromagnetic valve 2 of the first embodiment (in FIG. 19B, for the sake of simplicity, the structure of the diaphragm 6 is larger than that of FIGS. 4, 6, and 7. The illustration is simplified, and the illustration of the coating 9A is saved, and this is the same in FIG.

When the electromagnetic valve 2D is in the open state, fluid enters from the second fluid inlet / outlet port 12 as shown by an arrow LD1 in FIG. 19 (B). As shown by the arrow LD2, this fluid flows between the inner surface 6b of the diaphragm 6 and the annular edge 3e of the side plate portion 3c of the yoke 3, and between the inner surface 6b of the diaphragm 6 and one end 4e of the pole piece 4. The gap and the gap between the recess 4d of the one end 4e of the pole piece 4 and the elastic body 8 are sequentially passed through the opening 4o of the one end 4e to flow out from the first fluid inlet / outlet 11 as indicated by the arrow LD3. To do. In this way, fluid can flow through the electromagnetic valve 2D from the second fluid inlet / outlet 12 toward the first fluid inlet / outlet 11 or vice versa.

When the electromagnetic valve 2D is in the closed state, the diaphragm 6 approaches the one end 4e of the pole piece 4 as in the electromagnetic valve 2 of the first embodiment, and the opening 4o is closed by the elastic body 8. Can be removed. Further, the back side pressure P0 is applied to the back surface 6a of the diaphragm 6 from the second fluid inlet / outlet 12 through a gap between the outer peripheral wall 10-3 of the main case 10B and the peripheral edge portion 6e of the diaphragm 6. Accordingly, the closed state is assisted in the same manner as in the solenoid valve 2 of the first embodiment.

In this electromagnetic valve 2D, it is possible to avoid the cylindrical portion 10b forming the second fluid inlet / outlet 12 from projecting to the outside (+ Z side) from the second end wall 10-2 of the lid case 10A. Thereby, a solenoid valve can be reduced in thickness. For example, the main case 10B is attached along the upper surface of the wiring board (not shown), and the protrusion 4a that forms the first fluid inlet / outlet 11 extends downward through the wiring board, so that the electromagnetic valve 2D The wiring board and the wiring board can be configured flat as a whole.

20A and 20B show another example electromagnetic valve 2E obtained by modifying the case 10 of the electromagnetic valve 2 of the first embodiment. FIG. 20A shows the electromagnetic valve 2E viewed from the + Z side. FIG. 20B shows a cross-sectional structure viewed from the lower side (−Y side) in FIG. As can be seen from this figure, in this solenoid valve 2E, the cylindrical portion 10c forming the second fluid inlet / outlet 12 is disposed so as to protrude from the first end wall 10-1 of the main case 10B to the outside (−Z side). Has been. Other points are the same as those of the solenoid valve 2 of the first embodiment.

When the electromagnetic valve 2E is in an open state, fluid enters from the second fluid inlet / outlet port 12 as shown by an arrow LE1 in FIG. 20 (B). As shown by an arrow LE2, this fluid flows between the outer peripheral wall 10-3 of the main case 10B and the side plate 3c of the yoke 3, the inner surface 6b of the diaphragm 6 and the annular edge 3e of the side plate 3c of the yoke 3. The gap between the inner surface 6b of the diaphragm 6 and the one end 4e of the pole piece 4, the gap between the recess 4d of the one end 4e of the pole piece 4 and the elastic body 8 in this order, and the one end 4e. And flows out from the first fluid inlet / outlet port 11 as indicated by an arrow LE3. In this way, fluid can flow through the electromagnetic valve 2E from the second fluid inlet / outlet 12 toward the first fluid inlet / outlet 11 or vice versa.

When the electromagnetic valve 2E is in the closed state, the diaphragm 6 approaches the one end 4e of the pole piece 4 and the opening 4o is closed by the elastic body 8 as in the electromagnetic valve 2 of the first embodiment. Can be removed. Further, from the second fluid inlet / outlet 12, a gap between the outer peripheral wall 10-3 of the main case 10B and the side plate portion 3c of the yoke 3, and between the outer peripheral wall 10-3 of the main case 10B and the peripheral portion 6e of the diaphragm 6 are provided. The back side pressure P0 is applied to the back surface 6a of the diaphragm 6 through the gaps in order. Accordingly, the closed state is assisted in the same manner as in the solenoid valve 2 of the first embodiment.

In this solenoid valve 2E, as in the solenoid valve 2D, the cylindrical portion 10c forming the second fluid inlet / outlet 12 protrudes from the second end wall 10-2 of the lid case 10A to the outside (+ Z side). Can be avoided. Thereby, a solenoid valve can be reduced in thickness. Further, in the electromagnetic valve 2E, the cylindrical portion 10c forming the second fluid inlet / outlet 12 can be protruded in the same direction (the −Z direction) as the protruding portion 4a forming the first fluid inlet / outlet 11. For example, the main case 10B is attached along the upper surface of a wiring board (not shown), and both the cylindrical portion 10c and the protruding portion 4a extend downward through the wiring board, so that the electromagnetic valve 2E and the wiring Together with the substrate, it can be configured flat as a whole. In this case, the flow path connected to the electromagnetic valve 2E can be disposed only below the wiring board.

In addition, the deformation | transformation of case 10 shown to FIG. 19 (A), FIG. 19 (B), FIG. 20 (A), and FIG. 20 (B) can be applied similarly to the solenoid valve 2B of Example 2.

(Application to equipment)
In the above-described embodiment, the electromagnetic valve of the present invention is applied to a sphygmomanometer. However, the present invention is not limited to this. The electromagnetic valve of the present invention can be applied to various devices other than a blood pressure monitor. Moreover, the solenoid valve of this invention can be applied also to the apparatus containing the function part which performs a blood pressure measurement function and other various functions. In that case, the device can be configured to be small and lightweight. In addition, even if the attitude of the solenoid valve changes variously with respect to the vertical direction, since the change in characteristics (for example, the current-flow characteristic versus the current flow) is small, the solenoid valve can be opened and closed stably and reliably. Therefore, the operation of the device can be stabilized.

The above embodiments are merely examples, and various modifications can be made without departing from the scope of the present invention. The plurality of embodiments described above can be established independently, but combinations of the embodiments are also possible. In addition, various features in different embodiments can be established independently, but the features in different embodiments can be combined.

2, 2B, 2D, 2E, 2X Solenoid valve 3 Yoke 4 Pole piece 5

Coil spring

6, 6B Diaphragm 7 Solenoid coil 8

Elastic body

9A, 9B Coating 10 Case 10-1 First end wall 10-2 Second end Wall 10-3 Outer peripheral wall 11 First fluid inlet / outlet 12 Second fluid inlet / outlet 100 Sphygmomanometer

Claims

A solenoid valve that allows or blocks fluid flow,
A yoke including an end plate portion having an annular periphery, and a side plate portion connected to the periphery of the end plate portion and surrounding the space adjacent to one side of the end plate portion in an annular shape;
A pole piece extending in one direction from one end existing in the space on one side to the other end on the opposite side, perpendicular to the end plate portion of the yoke, and the pole piece is open to the one end A first fluid inlet / outlet communicating with the opening through the pole piece at the other end,
A solenoid coil housed in an annular space between the pole piece and the side plate of the yoke;
A diaphragm made of a plate-like magnetic material facing the end plate portion of the yoke through the space and having a dimension extending over the annular edge of the side plate portion of the yoke;
A biasing portion that biases the diaphragm in a direction to move away from the one end of the pole piece in a manner to move the diaphragm in parallel in the one direction,
During non-operation when the solenoid coil is in a non-energized state, the diaphragm is separated from the one end of the pole piece by the urging force of the urging unit, and the opening is opened.
During operation in which the solenoid coil is energized, the diaphragm approaches the one end of the pole piece against the urging force of the urging portion by the magnetic force generated by the solenoid coil, and the opening is closed. Closed state,
The diaphragm covers the entire circumference of the peripheral end surface around the opening or the entire circumference of the annular edge of the side plate portion of the yoke from the center toward the peripheral edge. In the closed state, the inner surface on the side facing the end plate portion of the diaphragm is the peripheral end surface around the opening of the one end of the pole piece, or in the closed state, or A solenoid valve characterized in that it is in close contact with the annular edge of the side plate portion of the yoke.
The solenoid valve according to claim 1,
The electromagnetic valve, wherein the pole piece and the yoke are integrally formed.
The solenoid valve according to claim 1 or 2,
A magnetic valve, wherein the magnetic material forming the diaphragm is permalloy.
In the solenoid valve according to any one of claims 1 to 3,
An electromagnetic valve, wherein an elastic body for closing the opening is integrally attached to a portion of the diaphragm facing the opening at the one end of the pole piece.
The solenoid valve according to claim 4,
The said pole piece has the hollow opened toward the said elastic body attached to the said diaphragm in the said one end part, The said opening is opened in the bottom of this hollow, The electromagnetic valve characterized by the above-mentioned.
In the solenoid valve according to any one of claims 1 to 5,
With the other end of the pole piece exposed to the outside, the yoke, a portion of the pole piece that extends into the space on the one side, the solenoid coil, the diaphragm, and the biasing portion, With a hermetically sealed case that fluidly and collectively covers
A solenoid valve characterized in that a second fluid inlet / outlet is provided through the outer wall of the sealed case.
The solenoid valve according to claim 6,
The sealed case includes a first end wall along an outer surface of the end plate portion of the yoke, a second end wall along a back surface facing the side opposite to the end plate portion of the diaphragm, An electromagnetic valve comprising: an annular outer peripheral wall connecting a peripheral portion of the first end wall and a peripheral portion of the second end wall.
The solenoid valve according to claim 7,
The electromagnetic valve according to claim 1, wherein the other end portion of the pole piece provided with the first fluid inlet / outlet is disposed to protrude outward from the first end wall of the sealed case.
The solenoid valve according to claim 7 or 8,
The electromagnetic valve, wherein the second fluid inlet / outlet is disposed to protrude outward from the first end wall, the second end wall, or the outer peripheral wall of the sealed case.
The solenoid valve according to any one of claims 7 to 9,
The urging portion includes a coil spring disposed along an annular space between the side plate portion of the yoke and the outer peripheral wall of the sealing case.
The solenoid valve according to any one of claims 1 to 10,
The diaphragm extends spatially continuously from the center toward the peripheral edge until it covers the annular edge of the side plate portion of the yoke,
A solenoid valve characterized in that a notch that stops at a position corresponding to the annular edge of the side plate portion of the yoke is provided in the peripheral portion of the diaphragm toward the center.
The solenoid valve according to any one of claims 1 to 11,
In the closed state, the diaphragm is arranged so that the inner surface of the diaphragm and the peripheral end surface around the opening of the one end of the pole piece or the annular edge of the side plate of the yoke are in close contact with each other. A coating having elasticity is provided on the inner surface of the first or second end of the pole piece, the peripheral end surface around the opening, or the annular edge of the side plate of the yoke. solenoid valve.
A sphygmomanometer that measures the blood pressure of a measurement site,
The body,
A cuff attached to the measurement site;
A pump mounted on the body for supplying fluid to the cuff through a flow path;
The solenoid valve according to any one of claims 1 to 12, which is mounted on the main body and interposed between the pump or the flow path and the atmosphere;
A pressure controller for controlling the pressure of the cuff by supplying fluid to the cuff through the flow path by the pump and / or discharging the fluid from the cuff through the electromagnetic valve;
A blood pressure calculator that calculates blood pressure based on the pressure of the fluid contained in the cuff,
The sphygmomanometer, wherein the solenoid valve is inserted such that a back surface of the diaphragm communicates with the pump or the flow path, and the first fluid inlet / outlet faces the atmosphere side.
A sphygmomanometer that measures the blood pressure of a measurement site,
The body,
With a cuff attached to the measurement site,
The cuff includes a measurement fluid bag disposed in contact with the measurement site, and a pressing fluid bag disposed on the outer peripheral side of the measurement fluid bag,
A pump mounted on the main body for supplying fluid to the pressing fluid bag and the measuring fluid bag;
A first flow path connecting the pump and the pressing fluid bag so as to allow fluid flow;
A second flow path in which the pump or the first flow path and the measurement fluid bag are connected so as to allow fluid flow, and an on-off valve is inserted;
A pressure control unit that performs control for supplying the fluid to the pressing fluid bag from the pump through the first flow path and compressing the measurement site;
A blood pressure calculator that calculates blood pressure based on the pressure of the fluid contained in the fluid bag for measurement,
The on-off valve comprises the electromagnetic valve according to any one of claims 1 to 12,
In the second flow path, the on-off valve is inserted with the rear surface of the diaphragm facing the upstream side communicating with the pump and the first fluid inlet / outlet facing the downstream side communicating with the measurement fluid bag. A blood pressure monitor characterized by
A blood pressure measurement method for measuring blood pressure at a site to be measured using the sphygmomanometer according to claim 14,
With the cuff attached to the part to be measured, the solenoid coil is de-energized, the open / close valve is kept open, and the fluid is transferred from the pump to the pressing fluid bag through the first flow path. And a preliminary supply step of supplying a predetermined amount of the fluid from the pump or the first flow path through the second flow path,
A switching step of switching the solenoid valve from an open state to a closed state by energizing the solenoid coil;
While maintaining the on-off valve in a closed state, the pressure control unit supplies the fluid to the pressing fluid bag from the pump through the first flow path and compresses the measurement site, while the blood pressure calculation unit A blood pressure calculation step for calculating a blood pressure based on the pressure of the fluid contained in the measurement fluid bag,
A method for measuring blood pressure, wherein the energization amount of the solenoid coil is set to be smaller than the energization amount of the solenoid coil immediately after being switched to the closed state during the period of being kept in the closed state. .
A device capable of measuring the blood pressure of a measurement site,
The body,
A cuff that extends from the main body and is attached to the measurement site;
A pump mounted on the body for supplying fluid to the cuff;
The solenoid valve according to any one of claims 1 to 12, which is mounted on the main body,
A pressure controller that controls the pressure of the cuff by supplying fluid to the cuff by the pump and / or discharging the fluid from the cuff through the solenoid valve;
An apparatus comprising: a blood pressure calculation unit that calculates a blood pressure based on a pressure of the fluid contained in the cuff.